The construction of high stability heterogeneous catalyst for privileged common catalysts is a benefit for the reuse and separation catalyst from reactants. Herein, a palladium diphenylphosphine-base Hollow-shell-structured mesoporous catalyst (HS@PdPPh2@MSN) is prepared by the immobilization of bis[(diphenylphosphino)ethyltriethoxysilane] palladium acetate onto the inner wall of mesoporous organicsilicane Hollow-shell whose surface be protected by -Si(Me)3 group. In detail Hollow-shell-structured (PPh2)2Pd(OAc)2- functionalized mesoporous silica nanoparticles, abbreviated as HS@PdPPh2@MSN , were synthesized through a simple post-grafting complexation three-step procedure, as shown in Scheme 1. The first step was the co-condensation of tetraethoxysilane (TEOS) and 1,2-bis(triethoxysilyl)ethane, followed by the modification of hexamethyldisilazane (HMDS) leading to silylated core-shell-structured nanoparticles Me@SiO2@NPs. The second step was the post grafting of diphenyl(2- (triethoxysilyl)ethyl)phosphane within the inner surface of the silylated Me@HS@MSN (1), which was obtained by an etching process in toluene for 12 h under refluxing condition. The third step was the direct complexation of the immobilized diphenyl(2-(triethoxysilyl)ethyl)phosphane with Pd(OAc)2 in the cavity of the hollow-shell-structured mesoporous silica and producing of the coarse catalyst 3, which was subjected to a Soxhlet extraction to remove the unreactive materials providing its pure form as a gray powder. Structural analyses and characterizations of the heterogeneous catalyst reveal its well defined single-site active species within its silicate network. Electron microscopies confirm its Hollow-shell-structured mesoporous material. As presented in this study, the newly constructed heterogeneous catalyst enables an efficient Suzuki-Miyaura cross-coupling reaction for a range of substrates with up to 95% yield in mild conditions. Meanwhile, the HS@PdPPh2@MSN possessed excellent stability and recyclability, which could be reused at least five times without significant loss of activity. Furthermore, the HS@PdPPh2@MSN is easily synthesized and cost-effective, which makes it a candidate for applications in fine chemical engineering.
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Background and Objectives: Osteoporosis is a common bone disorder with marked morbidity and mortality that occurs frequently in women after menopause. Inadequacy of current treatments and their side effects has driven the search for improved approaches. This study attempted to evaluate the early use of either bone marrow-derived mesenchymal stem cells (BM-MSCs), or platelet-rich plasma (PRP), or both combined to slow down bone loss, and improve bone formation in rats following ovariectomy. Materials: In our study, female rats were divided into five groups: sham-operated (SHO) control, ovariectomized (OVX) untreated group, OVX-MSCs treated group, OVX-PRP treated group, and OVX-MSCs/PRP treated group. Body mass index (BMI) had been measured in all groups; furthermore, serum calcium (Ca2+), phosphorus (P), alkaline phosphatase (ALP), collagen type 1 cross-linked C-telopeptide (CTx-1), malondialdehyde (MDA), and tumor necrosis factor alpha (TNF-α) were assessed. Additionally, specimens of tibia were analysed by light microscopy, morphometry and immunohistochemical staining for osteopontin (OPN). Results: The results showed a significant increase of the final BMI in all groups. The OVX untreated group showed an insignificant change in the serum Ca2+ level, while the serum P level, together with ALP, CTX 1, MDA and TNF- α, showed a significant elevation. Administration of either BM-MSCs, or PRP, or their combination, significantly reduced serum levels of Ca2+, ALP, CTX-1, MDA, and TNF-α, however, the combination therapy showed most significant results, including the final BMI. Histological examination also confirmed rapid bone formation in the combined therapy group with in vivo osteogenesis demonstrated via positive immunohistochemical staining of OPN. Conclusion: The present study demonstrates that early administration of a combination therapy can have a therapeutic benefit over every monotherapy for the treatment of osteoporosis.
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Palm Oil Mill Efuents (POME) are complex fermentative substrates which habour diverse native microbial contaminants. However, knowledge on the microbiota community shift caused by the anthropogenic efects of POME in the environment is up to date still to be extensively documented. In this study, the bacterial and archaeal communities of POME from two palm oil processing systems (artisanal and industrial) were investigated by Illumina MiSeq Platform. Despite the common characteristics of these wastewaters, we found that their microbial communities were signifcantly different with regard to their diversity and relative abundance of their different Amplicon Sequence Variants (ASV). Indeed, POME from industrial plants harboured as dominant phyla Firmicutes (46.24%), Bacteroidetes (34.19%), Proteobacteria (15.11%), with the particular presence of Spirochaetes, verrucomicrobia and Synergistetes, while those from artisanal production were colonized by Firmicutes (92.06%), Proteobacteria (4.21%) and Actinobacteria (2.09%). Furthermore, 43 ASVs of archaea were detected only in POME from industrial plants and assigned to Crenarchaeota, Diapherotrites, Euryarchaeota and Nanoarchaeaeota phyla, populated mainly by many methaneforming archaea. Defnitively, the microbial community composition of POME from both type of processing was markedly different, showing that the history of these ecosystems and various processing conditions have a great impact on each microbial community structure and diversity. By improving knowledge about this microbiome, the results also provide insight into the potential microbial contaminants of soils and rivers receiving these wastewaters.
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Graphene oxide and its derivative have attracted extensive interests in many fields, including catalytic chemistry, organic synthesis, and electrochemistry, recently. Transition metal complexes are one of the most useful and powerful catalysts for industrial processes. However, the practical applications of homogeneous metal complexes are hampered by their high costs with problems of separating from the reaction mixtures. Therefore, designing heterogenized metal complex catalysts is of great interest for economic and environmental reasons in recent years [1-5]. Catalytic epoxidation [6] of styrene is an important practical reaction for producing styrene oxide which is an important industrial organic intermediate and is used in the synthesis of fine chemicals and pharmaceuticals [7].A Mn (salen) complex has been homogeneously immobilized on a modified graphene oxide (GrO) support via covalent bonding. The loading of Mn (salen) complex on GrO nanosheets was monitored by FTIR, TG-DTA, and elemental analyses. The catalytic properties of Mn (salen) - Graphene oxide compound in the oxidation of styrene with H2O2 as oxidant were investigated and compared with the properties of their homogeneous analogues. It was found that both heterogeneous Mn (salen) catalysts were more active than their homogeneous analogues and that the product selectivity varied in cases of different oxidants. The supported Mn (salen) complex showed high yield of styrene oxide (86.0%) and good recoverability when using air as oxidant.
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A sensitive and a precise method was developed for the quantification of different Sudan dyes in some Egyptian food samples. They were analyzed utilizing two fragment ion transition under multiple reactions monitoring (MRM) mode. Separation was carried out on Kinetex 2.6u C18 100 A (75 mm ×4.6 mm) phenomenex using isocratic elution with 10:90% water and acetonitrile containing 2.0 mmol/L ammonium formate and 0.2% formic acid. The validation parameters were obtained and verified. The linearity was 0.2-10.0 ng/mL with r2> 0.9975. LOD and LOQ were 0.06 and 0.19 ng/mL, respectively for Sudan (I, II) whereas they were 0.07 and 0.23 ng/mL, respectively for Sudan (III and IV), and Sudan Orange G. Recoveries are ranged from 78.79 to 110.49%. The method has been successfully applied for the quantification of these dyes in 60 food samples such as spices, chili powder, turmeric, paprika, and curry. The results show that about 55% of the randomly selected food samples were adulterated with the banned dyes.
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Bio-based membranes are widely used in many separation processes such as Gas separation (GS), Nano-filtration (NF), Ultra-filtration (UF), etc. In this work, PLA and its blends has been used for a bio based polymeric membranes synthesis that can be applied for fractionation of bioactive materials. PLA manufacturers around the world have been working seriously to develop solutions to some chronic limitations especially brittle behavior. The limitations also include their susceptibility to degradation and loss of inherent properties during processing and reprocessing. In addition, bio-based polymers and blends have less flexibility in polymer design as that of copolymers. In many applications, biopolymers require additives that do not inhibit their ability to compost. Very limited research had been cited on toughening properties of bio-based membranes suited for bioactive recovery. Hence, we attempted to formulate and synthesize PLA membrane with its appropriate blend to increase it toughness. From the study conducted, it was observed that the blend composition of PLA with PCL (Polycarprolactone), CNSL (Cashewnutshell liquid), PEG (Polyethyleneglycol) are the appropriate blends for toughness improvement and reproduceable hydrophilic nature.
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In the present research work Ni+TiB2 metal matrix composite coating was deposited on AA6061 aluminium alloy substrate using nickel and titanium diboride as precursor by gas tungsten arc cladding process. The TIG torch was used as heat source to melt the preplaced powder mixture. The mixture of TiB2 and Ni powders were taken as 10 wt. % and 90 wt. % respectively. The three level of currents were used as variable parameters to melt the preplaced powder layer viz. 120Amp, 140Amp and 150Amp. The microstructure of coated layer was investigated by field emission scanning electron microscope (FESEM) and the chemical composition of the coated layer was detected by energy dispersive spectroscopy (EDS). From the microstructural study it was found that the coating exhibits good metallurgical bond between coated layer and substrate. For analyzing the micro-hardness of coated layer Vickers micro hardness testing was performed along the cross-section of the coated samples. The maximum microhardness value of coated layer was 1233 HV, for sample cladded at current of 150 Amp. It was observed that increase in micro hardness value of coated sample was about 11 times higher than that of the aluminium alloy substrate (110HV). It was found that with increase in applied current, amount of microhardness of coated sample increased.
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Phthalocyanines (Pc), which contain peripheral and non-peripheral substituents and include rare-earth elements, are important objects of research and practical applications in various fields of science and technology. The most relevant are double-decker complexes of phthalocyanines with lanthanides, which suggest a variety of uses due to their distinctive optical and electrical properties. Sandwich-type complexes are used as organic semiconductors, catalysts, photodetectors and electrochemical sensors. The architectural flexibility of these compounds can be used to adjust molecular properties such as aggregation, solubility and optical absorption. The aim of this study is to search for selective approaches to the synthesis of tetra- and octaphenoxy-substituted metal complexes of phthalocyanine with gadolinium and neodymium. Introduction of steric substituents into peripheral and non-peripheral positions of the phthalocyanine macrocycle will improve their solubility and reduce the ability to aggregate in solutions. The presence of axial ligands and the high coordination capacity of lanthanides will also contribute to improving the solubility of the target complexes. Synthesis of metal complexes was carried out by template condensation of the corresponding phthalonitriles with gadolinium and neodymium salts in a molar ratio of 3:1 in the presence of DBU. Product separation was carried out on a chromatographic column on silica gel. The obtained compounds were infected using modern physicochemical methods. The work includes study of the introduction of peripheral and non-peripheral substituents effect and the nature of the salt on the yield of target products. Spectral characteristics in organic solvents (chloroform, THF, DMF) of the obtained complexes were studied. It was determined that the preferred product of the syntheses is a sandwich-type complex. It was also found that when used in the synthesis of double-deck complexes of gadolinium and neodymium by template condensation by fusion in the presence of DBU leads to the formation of a sandwich molecule, which, due to the presence of a base, is in a mixture of neutral-radical and reduced forms. This work was supported by the Russian Science Foundation (grant № 17-73-20017).
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Among various other product impurities sequence modification in protein bio-therapeutics can be categorized as undesired product variant. These sequence variants (SV) may possess altered physicochemical and or biological properties compared to wild-type product, which can affect the overall efficacy, stability or safety of the biomolecule drug. Early detection of specific sequence modifications is therefore desirable in product manufacturing. Because of their low abundance, and finite resolving power of conventional analytical techniques, they are often overlooked in early drug development. However, once the mutation is identified: genetic or misincorporation, the clone is rejected and the cell line is changed or further optimized in upstream media supplements, respectively. Depending on the stage of the development, this approach may incur a moderate to significant delay in reaching the drug to patients. In case, the sequence variant is in a functionally inactive region of the protein the impact can be nullified theoretically and the development can move forward with a risk possibility of failing in immunogenicity during the clinical trial. The present topic discusses a case study where trace amount of a sequence variant is identified in a monoclonal antibody (mAb) based therapeutic protein by LC–MS/ MS. The sequence variant was enriched during downstream processing of the antibody for further extensive characterisation using biophysical techniques and biological assays to exploit its physicochemical properties for downstream purification of desired drug product. Using a very sensitive selected reaction monitoring (SRM) technique, this SV was quantitated in in-process samples which revealed both prominent and inconspicuous nature of the variant in process chromatography assisting in devising control strategy for sequence variant in the final product. This way as low as <0.05% upper limit could be achieved for sequence variant in the drug product utilizing SRM based mass spectrometry method during the purification steps.
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Heartsease (Viola tricolor L) of the Violaceae family is used for biological and pharmacological usages due to its antioxidant substances. Nanotechnology plays an important role in increasing agricultural productivity using biological nanoparticles Silver nanoparticles (AgNPs) are new metallic compounds with numerous physiological and biological properties, which are widely used in medical industries and so on. In the present study, plant-mediated nanosilver was produced from aqueous extract of Pansy flower as a good covering and stabilizing agent using the green synthesis method. Silver nanoparticles (AgNPs) are new metallic compounds with numerous physiological and biological properties, the presence of synthesized Ag-NPs was first confirmed with Dynamic light scattering, transmission electron microscopy, and zeta potential analyses. In this study, the effect of different concentrations of bio nanosilver 0, 10, 50, and 100 mg/L on phytochemical and physiological properties, and the expression of some key genes involved in flavonoids biosynthesis including phenylalanine ammonia-lyase (pal), chalcone synthase (chs), flavonoid '3', '5-hydroxylase (f3'5'h), and flavonoid 3'-hydroxylase (f3'h) were determined in V.tricolor plant.The results showed nanosilver treatments cause the accumulation of manganese, zinc, and silver elements and increasing the content of phenolic, flavonoid, anthocyanin and antioxidant activity . Using AgNPs also cause the increase of activity of antioxidant enzymes such as superoxide dismutase, ascorbate peroxidase, phenylalanine ammonia-lyase, and peroxidase. Besides, treatment with a concentration of 10 mg/L of silver nanoparticles significantly causes an increase in flavonoids compounds such as rutin, apigenin, and quercetin. In general, we found that silver nanoparticles could increase of secondary metabolites content in the V.tricolor plant. Nanoparticles can exert the inhibitory effect of DDPH free radicals in a dose-dependent manner. According to the results, AgNPs stimulated the antioxidant activity and increased secondary metabolites (flavonoid content).
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Backbround: Natural product is organic substance produced by living organism found in the nature. It can be in form of primary and secondary metabolites. These have pharmacological activity which is beneficial various kinds of diseases. Natural products have been an important source for drug development over the years as more than 70% of the currently available drugs are either directly from natural sources or semi-synthetic analogues of natural products or molecules developed inspired by natural products. Aims/Objectives: Keeping in view of the importance of natural product scaffolds in cancer and bacterial drug discovery, we aimed at the development of some new secondary leads based on capsaicin and their computational calculation. Methodology: A library of new capsaicinoids has been synthesized through a two point modification around 4-hydroxy-3-methoxybenzyleamine moiety by varying the nature and the length of lipophilic side chain and by bringing modifications at phenolic group. All the synthesized compounds were screened for their anti-proliferative activity against NCI panel of 60 human cancer cell lines, and bacterial NorA efflux pump inhibitors. All synthesized compounds were screened DFT and QSAR calculation. Results: New capsaicinoids resulted from the two point modification of capsaicin have demonstrated promising anti-proliferative activities with GI50s 0.3-30 µM against NCI panel of 60 human cancer cell lines. Among the cancer cell lines tested Colon cancer cell lines were found to be more susceptible to this class of compounds. The inhibitor displayed a minimum effective concentration of 12.5 µg/ mL against SA1199B which was better than its parent conjugates capsaicin (MEC 50µg/mL) and standard drug reserpine (MEC 25µg/mL). In computational study, some compounds revels good co-relation with colon cancer cell line (HCT-15, HT29 and KM12). Conclusion: In conclusion a promising lead molecule has been generated through two point modifications of capsaicin.
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In the last decade, researches on bulk micro and nano bubbles have been attracting the attention of scientists and environmentalists in the field of wastewater treatment. Many patented and open-sourced literatures reports on the techniques on the bulk generation of nanobubbles and its underlying research and applications. However, the major drawback in these studies are the bubble concentration and their size distribution. Moreover, there are challenges related to scale-up applications (particularly on pilot and industrial scale) which limits their applications for handling wastewaters with high flow rates. Nano bubbles (1 – 100 nm diameter) present excellent and interesting characteristics such as high surface to volume ratio, high longevity and stability, good surface charge density and tendency to form aggregates of hydrophobic particles. These results demonstrate the futuristic technological advancements not only with nano bubbles but also in combination with macro (diameter = 100 µm – 2 mm) or micro bubbles (1 – 100 µm diameter). Nevertheless, most of the research has been devoted to the generation of nano bubbles by hydrodynamic cavitation or depressurization of air (saturated with water) in various flow constrictors (orifice, needle valves, venturi). In the field of metallurgy, nanobubbles serve the purpose of accelerating the recovery rate and flow kinetics of both ultrafine and fine particles at lower amounts of collector and frother. In wastewater treatment, nano bubbles significantly enhance the removal of different pollutants (organic/inorganic precipitates, ions, colloidal solids, emulsified oils, residues) via floatation accompanied with bigger bubbles (micro or macro). Future researches on nano bubbles should focus on more promising bubble generation techniques with high rate of mass transfer, studies on economic analysis through experiments on pilot scale handling real wastewater with continuous injection of bubbles.
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Melvin Calvin won the 1961 Nobel Prize in chemistry for the discovery of the canonical photosynthetic carbon reduction cycle in collaboration with Andrew A. Benson and James A. Bassham and a personal glimpse provides insight into this American force in physical chemistry and inspiration for the future of innovations in chemistry. He was born in St. Paul, Minnesota, USA, on April 8, 1911, and lived until 1997. His father was from Lithuania and his mother was from Russia. Calvin investigated artificial photosynthesis, the physical chemistry of color in porphyrins, the origin of life, cancer, the biochemistry of learning, moon rocks, and avenues to grow gasoline, as well as its related optimization of photosynthesis. The Calvin lab sought to modulate glycoregulation in the field, and yet this significant advancement has been achieved only today. Based on the discovery of the plant lectin cycle, BRANDT GlucoPro® plant growth regulator puts control of crop photosynthesis in the hands of farmers.
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Complexes of d- and f-metals with phthalocyanine ligands are promising compounds for creating materials with controlled photo physical and photochemical properties, as well as catalytic and sensory activity [1-2]. The presence of promising physicochemical properties of metal phthalocyanines is primarily due to the specifics of the coordination center of the macromolecule and its functional environment. The nature of the substituents in the peripheral and non-peripheral positions of the phthalocyanine macrocycle, on the one hand, determines their solubility in various media, and on the other hand, the possibility of the formation of oligomeric and polymeric molecular systems that retain the specified physicochemical properties due to ionic, coordination and covalent interactions. In addition, the nature of substituents in the macrocyclic backbone can determine the possibility of obtaining various materials with the participation of metal phthalocyanines. We have previously shown that immobilization of macrocycles on inorganic carriers, for example, silica, is promising in this case. It should be noted that in this case, not only the set of functional groups in the composition of the substituent, but also their spatial arrangement has a significant effect on the physicochemical properties of the materials obtained. The report presents the synthesis of a wide range of promising complexes of d-and f-metals with phthalocyanine ligands containing functional groups in peripheral and non-peripheral positions (cyano-, sulfo-, nitrocyclohexyl fragments, etc.), separated from the macrocyclic backbone by spacer phenoxyl chains of various length. An analysis is given of the relationship between the nature of the spacer fragment of macrocycles and their aggregation, spectral, luminescent properties, as well as the processes of molecular complexation in liquid-phase systems.
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The architectural design and construction processes bring a building into existence. In this existence the “body” of the building is the hardware; and the “soul” of the building consists of the environmental characteristics of that body. Most of the environmental assessment tools deal with the evaluation of the hardware such as outer shell, building materials, constructional details, building services, etc., and physical phenomenon of the indoor environment such as IAQ, thermal quality, lighting, etc. However the conceptual meaning of the environment includes relations and dependencies as well as the physical conditions and surroundings. Physical surroundings and conditions are based on real, objective facts such as climate, energy, water, etc. which can be measured by devices; whereas relations and dependencies are based on more abstract, subjective facts such as socio-cultural characteristics, norms, beliefs etc. which cannot be measured by any device. While the science and technology deal with the physical aspects social science examines the relations. Those of conceptual approaches come and knot in many cases, and necessitate the interdisciplinary approaches. In this presentation two cases will be demonstrated as samples of interdisciplinary work. First is consideration of IAQ and the architectural design process within the building system; and the second is placing social criteria within the green building assessment tools. Since the speaker is an architect and the congress is on advanced chemistry, the aim of this sampling is to share the idea of realizing something related to one’s professional area in another professional’s field; and realizing something related to the another professional’s area in one’s professional field. Those of metaphorical approaches bring the uniqueness and richness in knowledge.
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Bioelicitors are one of the management methods to induce the improvement of quantitative and qualitative performance of medicinal plants. The use of beta-cyclodextrin nanoparticles is described as a new protection strategy of the plant and induces a plant defense response. In this study, β-cyclodextrin nanoparticles (β-CDNPS) were synthesized. The nanoparticle profile was determined by UV-VIS spectrum, transmission electron microscopy (TEM) and dynamic light scattering (DLS). Then different concentrations of β-CDNPs including 0, 10, 50, 100 mg / l were used for foliar spray of basil (Ocimum basilicum c.v. Keshkeni luvelou). The amount of chlorophyll pigments and basil essential oil was significantly different (P≤ 5%) compared to the control. The maximum amount of chlorophyll b was observed in 100ppm treatment. Membrane stability index was assessed by measuring the electrolyte leakage of leaves and roots. A significant reduction (P≤5%) of ion leakage and malondialdehyde of roots and leaves was observed in the treatment of 50mg/l β-Cyclodextrin nanoparticle which indicates an increase in enzyme activity. Soluble sugars and proline of basil leave and root in 50ppm treatment had a significant increase (P≤%5) compared to the control, so that insoluble sugars in leave and root showed the opposite trend. In the presence of β-CDNPS, phenylpropanoids and terpenoids concentration, in the basil showed a significant difference (P≤5%) compared to the control group. Induction of β-Cyclodextrin nanoparticle in the biosynthesis pathway of secondary metabolites results in plant productivity. According to molecular analysis, eugenol O-methyltransferas(EOMT) and chavicol O-methyltransferas(CVOMT) genes expression in methyl eugenol and methyl chavicol biosynthesis pathways were significantly improved when treated with 50 ppm concentration compared to the control. Therefore, foliar spray at the right concentration can act as an inducer while stimulating, preserving the active ingredients in basil and increase the content of essential oil for food and drug consumption.
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Post consume waste plastics (WP) and coal fly ash (FA) have been regarded as great environmental hazard because suitable disposal pathways has yet not been established for them. The amount of waste plastic is increasing because of the rapid growth of polymer consumption, short service life and non-degradable properties. On the other hand, FA, a coal combustion residue of thermal power plants has been regarded as a problematic solid waste all over the world. In this study, FA samples were modified with NaOH and H2SO4. The mineralogical and microstructural characterization were carried out by means of X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS) and Braunauer-Emmett-Teller’s multilayer adsorption theory (BET). Waste low-density polyethylene (LDPE) and high-density polyethylene (HDPE) were degraded using a semi-batch reactor along with modified fly ash catalysts. The liquid products were analyzed using FTIR, nuclear magnetic resonance (1H, 13C, and DEPT-135 NMR), and gas chromatography–mass spectrometry (GC–MS). Experimental data showed that cenospheres were dominated with quartz and mullite glasses with both amorphous and crystalline phases. The acid treatment increased Si/Al ratios by removing impurities and dealuminations, whereas alkali treatment significantly increased total pore volume. Both of the waste plastics were degraded at 400–450°C., and the highest yield of liquid fuel product (about 87.24 wt%) was achieved for base treated FA at a polymer and catalyst ratio of 25 w/w. The NMR results accompanied by GC–MS data ensure that obtained fuels contain both aliphatic (saturated and unsaturated) and aromatic hydrocarbons, and FA is an efficient catalyst to pyrolize waste plastics into light weight liquid (gasoline and kerosene) hydrocarbons. This plastic-to-fuel technology should be commercialized owing to be profitable and eco-friendly.
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The plausible explanation behind the stability of thermophilic protein is still yet to be defined more clearly. Here an insilico study has been undertaken by investigating sequence, structure of protease from thermophilic (tPro) bacteria and mesophilic (mPro) bacteria. Results showed that charged and uncharged polar residues have higher abundance in tPro. Total 6 conserve regions have been found in tPro sequences which are 100% conserved. In extreme environment, the tPro is stabilized by high number of isolated and network salt bridges. A novel cyclic salt bridge (R415-D502:R415-E419:K416-E419: K416-D502:R480-D502) is also found in a structure of tPro. High number of metal ion binding site also helps in protein stabilization of thermophilic protease. Aromatic-aromatic interactions also play a crucial role in tPro stabilization. Formation of long network aromatic-aromatic interactions also first time reported here. the high value of solvation free energy indicates that tPro are more stable than mPro. Presence of high number tyrosine phosphorylation site specially helps in tPro stabilization. This is a remarkable outcome of this study which also helps in protein engineering. This thermophilic protease can widely use in industrial application. Cause it can stable at very high temperature. It does not easily breakdown. Due to high stability, it can tolerate very extreme condition.
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The fundamental information required for designing a continuous FBR MOX spent fuel dissolution system is the fuel pellet’s intrinsic kinetics of dissolution under typical PUREX process conditions. Hence the dissolution behaviour of a typical FBR MOX fuel pellet in nitric acid was investigated. Influence of parameters, such as plutonium content of the MOX pellet, initial concentration of nitric acid, intensity of mixing and the temperature of the reaction mixture, on the dissolution behavior of typical FBR MOX pellets in nitric ut the differential rapid dissolution behavior of UO2 over PuO2 from the same MOX pellet under all the conditions of investigation. This differential dissolution was found to be inversely proportional to all the above evaluated influencing parameters except for the Pu content of the pellets in which case it was directly related. These results had paved way for better understanding of the dissolution mechanism of a typical FBR Pu rich MOX fuel under the conventional PUREX process conditions.
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The variety of applications of materials based on macroheterocyclic molecules is due to the wide possibilities of adjusting the structure of the resulting compound for a specific task by choosing a specific class of compounds, introducing suitable peripheral and non-peripheral substituents, and varying the central metal atom. Phthalocyanine complexes have established themselves as one of the most promising types of macroheterocycles due to the presence of an extended conjugated aromatic circuit, as well as intense light absorption in the area of the "therapeutic window". In turn, the introduction of a luminescent active metal atom into the coordination center of a molecule opens up opportunities for the use of complexes in the medical field as elements of diagnostics and PDT of tumor diseases.This work describes the synthesis and study of the spectral-luminescent properties of aryloxy-substituted phthalocyaninates with magnesium. The complexes were obtained by template fusion of substituted phthalodinitriles with magnesium (II) acetate in the absence of a solvent at 190 °C for 10 min. Purification was carried out using a column (silica gel M60, gradient elution with a mixture of ethanol (0 to 15 vol.%) in chloroform) and gel permeation chromatography (gel Bio-Beads S-X1, elution with a mixture of 2.5% ethanol in chloroform). The structure of the obtained complexes was confirmed using NMR, IR and electronic absorption spectroscopy, mass spectrometric analysis. Absorption maxima and molar light absorption coefficients of compounds in various organic media are determined, Stokes shifts, quantum yields and fluorescence lifetimes are calculated.
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Nanofibrillated cellulose derived from oil palm empty fruit bunches (NFC-OPEFBs) has a high potential for nano reinforcement in polymer composites. However, the hydrophilic surface of NFC-OPEFBs limits their usage as nanofiller for the hydrophobic polymers. To overcome the limitation, the enhancement hydrophobicity of NFC-OPEFBs was performed using a sustainable cationic surfactant, i.e., cetyltrimethylammonium chloride derived from palmityl alcohol through surface modification method. In this study, a modified NFC-OPEFBs was reviewed in terms of their effects on mechanical, water vapor permeability, and thermal properties of polylactic acid (PLA) nanocomposite films. The PLA nanocomposite films were prepared with the addition of unmodified NFC-OPEFB (unmodNFC) 0.5 wt%, with the addition of various amounts of modified NFC-OPEFB (modNFC) from 0.5 to 3.0 wt% into PLA matrix by the solvent casting method and neat PLA film as the control. The ultimate tensile strength of PLA films was increased by using 3.0 wt% of the modNFC 87.8 %, while it was decreased by using 0.5 wt% the unmodNFC. This result proved that the hydrophobicity of NFC could improve interfacial adhesion between PLA and NFCs. The water vapor permeability of PLA film was decreased by 36.0 % and 33.3 % with the addition of 2.0 wt% and 3.0 wt% modNFC, respectively. Moreover, the PLA+modNFC films exhibited overall higher crystallinity and higher glass transition temperature than those of neat PLA film. The transparency of PLA nanocomposite films with the incorporation of modNFC was clearer than that of unmodNFC at the same loading level observed with the visual transparency test using background images. This research revealed that the enhanced hydrophobicity of NFC might be used as nanofillers for other hydrophobic matrices such as polypropylene, polyethylene, and other hydrophobic polymers.
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Flood is one of the most destructive natural disasters globally and is a concern due to its high vulnerability. In this study for identification of flood susceptible areas, artificial neural network (ANN) and Multi-Attributive Border Approximation Area Comparison (MABAC) combined with Weights of Evidence (WoE) and Analytical Hierarchy Process (AHP) Models were used in Mazandaran province, Iran. MABAC method was used for the first time to evaluate the flood-prone areas in this study, and Attempts have been made for evaluate the performance of this new method by comparing with ANN model. The output of the neural network was discharge values in hydrometric stations. Using Geographic Information System (GIS) with eight effective factors including rainfall, distance from rivers, slope, soil, geology, elevation, drainage density, and land use, a flood model developed. Three precision parameters containingR^2, RMSE and MAE were applied to show the performance of the ANN model which yielded the values of 0.89, 0.0024 m^3/s, and 0.0018 m^3/s, respectively for testing data. The verification results indicated satisfactory agreement between the predicted and the real hydrological records. Also, based on flood inventory map and using the area under receiver operating curve, predictive power of the MABAC-WoE-AHP model was evaluated. The AUC value for prediction rate of this model was 86.1% which indicates the very good accuracy in predicting flood-prone areas. The results of ANN and MABAC-WOE-AHP methods indicated that respectively 48.83% and 46.93% of Mazandaran Province was located in high and very high risk of flooding area. Comparison of flood susceptibility maps for ANN and MABAC-WoE-AHP models showed the good agreement between two models that clarifies the efficiency of the new proposed method for future preventive measures.
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Radio-active sources are wildly used in the oil industry, building cites, hospitals, agriculture and more, for various applications. Being so widespread, they have a high potential to be easily diverted from their legal use, to serve as "dirty bombs" – Radioactive Dispersive Device. Nuclear forensics aims at the development of scientific capacity needed to prevent such terror acts, and attribution capabilities in the occurrence of such an event. An orphan radium-beryllium (Ra-Be) neutron source (Nuclear Chicago Corporation) detected inside a scrap metal shipping container, was seized and subjected to nuclear forensic analysis. Physical and chemical characterization methods were used before and after source dismantling. Non-Destructive Testing (NDT) proved to be most useful for initial analysis of the source. Dissolution of the Ra-Be capsule was followed with elemental analysis by Inductively Coupled Plasma (ICP) Atomic Emission Spectroscopy (AES) and Mass Spectrometry (MS). Model age determination by ICP-MS (81.6 y ± 4.08) was found to be sensitive to insufficient accuracy in measuring daughters present in the parent solution. Within this presentation, the term nuclear forensic will be discussed in view of the global threat of nuclear terror, following by a detail description of the Ra-Be neutron source characterization. The Ra-Be outer case (a), and magnification of text shown on the case (b): "Model P19 Nuclear Chicago" and (c): "Radioactive Material RaBe", are presented in the figure below, aside the neutron radiography of the source.
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This study has investigated the key contribution of sodium acetate as co-substrate on the performances of microbial fuel cells (MFC) during the conversion of a toxic blue-green algae (BGA) biomass into bioelectricity. Microcystis aeruginosa biomass was employed as a target substrate and sodium acetate (AC) as a co-substrate. Compared with MFC treated with BGA alone (MFC-BGA), the MFCs treated with BGA together with acetate (MFC-BGA-AC) significantly magnified the voltage output by 261.3%. Moreover, the addition of co-substrate extended the electric batch cycle by 253.1% and 7.9% compared with MFC-BGA-AC and its corresponding MFC treated only with AC (MFC-AC), respectively. The co-substrate strategy also enhanced the maximum power density by a factor of 3.53 MFC-BGA and 1.2 MFC-AC. It has also displayed the smallest charge transfer resistance of 12.01 Ω which was approximately 45.8% lower than that of MFC-BGA and even slightly lower than the control. Based on the transmission electron microscope results, the cell morphology was also less affected in MFC-BGA-AC. Thus, our new study revealed that the co-substrate could empower the bio-electrochemical active bacteria for toxin survival and make a crucial contribution in alleviating the internal resistance within the operating reactors, which consequently promote the transfer of the generated charges to the bio-anode for power production evolution. The current investigation will conspicuously help in paving ways toward sustainable clean energy production and durable wastes control in the aquatic environment. However, more studies exploring the feasibility of using non-commercial renewable wastes such as wastewater to replace commercial acetate as co-substrate are still needed to make this MFC technology more economic and sustainable.
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Graphene has recently attracted a significant attention with wide applications owing to its unique thermal, electronic, composite, and mechanical properties. Few-layer graphene was synthesized via a microwave-assisted catalytic graphitization. The microwave irradiation temperature and time played a key factor to synthesize the few-layer graphene. The highest degree of graphitization value and a well-developed pore structure was fabricated at 1300 °C using a 10% iron catalyst for 20 min. The produced FLG has been examined by Raman spectroscopy, X-ray diffraction, Transmission electron microscopy, and Atomic force microscopy. A high-resolution transmission electron microscopy analysis confirmed that the fabricated few-layer graphene consisting of 3–6 layers. In addition, the 2D band at 2700 cm−1 in the Raman spectrum indicated the presence of graphene layers. The Raman mapping also represented the catalyst loaded sample was homogeneously distributed and displayed a few-layer graphene sheet. The highest I2D/IG value indicated a few-layer graphene sheet at 10% iron loaded sample. Moreover, the few-layer graphene growth process was induced when iron oxide was reduced to metallic iron. The graphene nucleation and growth occurred via the dissolution-precipitation mechanism of bituminous coal and catalyst droplets. Finally, this technique assists in developing a cost-effective and environmentally friendly few-layer graphene fabrication process using a coal-based carbonaceous material.
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Here we investigate whether Wnt5A is associated with TGF-1/Smad2/3 and Hippo-YAP1/TAZ-TEAD pathways implicated in epithelial to mesenchymal transition (EMT) in the epithelial ovarian cancer. We used 2D and 3D cultures of human epithelial ovarian cancer cell lines SKOV-3, OVCAR-3, CAOV-4, and different subtypes of human serous ovarian cancer compared to normal ovaries specimens. Wnt5A showed a positive correlation with TAZ and TGF1 in high- and low-grade serous ovarian cancer specimens compared to borderline serous and normal ovaries. Silencing Wnt5A by siRNAs significantly decreased Smad2/3 activation and YAP1 expression and reduced nuclear shuttling in ovarian cancer (OvCa) cells. Furthermore, Wnt5A showed to be required for TGF1-induced cell migration and invasion. In addition, inhibition of YAP1 transcriptional activity by Verteporfin (VP) altered OvCa cell migration and invasion through suppression of Wnt5A expression and inhibition of Smad2/3 activation, which was reverted in the presence of exogenous Wnt5A. We found that the activation of TGF1 and YAP1 nuclear shuttling was promoted by Wnt5A-induced integrin alpha v. Lastly, Wnt5A was implicated in the activation of human omentum-derived mesothelial cells subsequent invasion of ovarian cancer cells. Together, we propose that Wnt5A could be a critical mediator of EMT-associated pathways.
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The unavoidable negative effects of global warming have been a key if not the most important issue occupying policy makers in the world at large today. The much talked about green economy nowadays seeks to achieve sustainable economic growth and development without compromising environmental quality. The relationship between environmental degradation and economic growth is largely explained by he environmental Kuznets Curve (EKC) hypothesis. By employing the basic postulation of the baseline EKC framework, this study proposes and tests the existence of a dualistic approach of the EKC hypothesis. Geometry is used to illustrate the proposed dualistic model. Meanwhile, the novel dynamic common correlation effect econometric technique is employed to test the existence of the dualistic EKC within a panel of 109 countries from 1995 to 2016. The outcome from the estimated models shows that, in the global sample, the existence of the dualistic U-shape and N-shape EKC hypothesis is validated. When the sample is split into sub samples based on income levels, the U-shape EKC hypothesis is validated for lower income and high income economies meanwhile, the N-shape dualistic EKC is mostly associated with high income economies.
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RNA nanotechnology resembles LEGO accretion or architecture construction with RNA as the major composition material including the scaffolding and functional groups. The ideal building material should have the following properties: 1) versatility and controllability in shape and stoichiometry; 2) spontaneous self-assembly when mixed together; and 3) thermodynamic, chemic, and enzymatic stability with a long shelf-life. RNA building blocks exhibits all of the above properties. In addition, RNA nanoparticles hold many unique and favorable properties that further enhance their applicability. RNA is a polynucleic acid making it a polymer. RNA is negatively charged, which prevents nonspecific binding to negatively charged cell membranes. RNA can be designed and manipulated with a level of simplicity of DNA while displaying versatile structure and enzymatic function attributed to proteins. RNA folds into a large variety of single stranded loops or bulges suitable for inter molecular or domain interactions. These loops or bulges can serve as mounting dovetails alleviating the need for external linking dowels in the nanoparticle construction. RNA nanoparticles display rubber- and amoeba-like properties, leading to compelling vessel extravasation to enhance tumor targeting and fast renal excretion to reduce toxicities. RNA nanoarchitectures are stretchable and shrinkable through multiple repeats like rubber, leading to an unusually high tumor targeting efficiency since their rubber or amoeba-like deformation property enables them to squeeze through leaky vasculature enhancing the EPR effect. RNA nanoparticles remain non-toxic since they can be rapidly cleared from the body via renal excretion into urine with little accumulation in organs and tissues. It was predicted in 2004 that RNA will be the third milestone in pharmaceutical drug development. The recent approval of several RNA drugs and the COVID mRNA vaccine by FDA suggests that this milestone is coming to realization.
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Huge amounts of textile wastes and by-products are discharged into the surroundings causing environmental problems and loss of possible profits. Wool wax is produced as a by-product from scouring of raw wool fleece and many small and medium enterprises don’t utilize them properly. Herein, we propose a novel approach for adopting green technologies for synthesis of new softener based on fatty acids derived from wool wax. The extracted fatty acids were condensed with a dihydroxy amino aliphatic short chain organic compound. The formed condensate was applied to acrylic fabric to enhance its performance attributes; Viz. imparting soft hand and reducing electrostatic charge. FTIR, GC-MS, 13C NMR, were adopted to assign the mechanism of reaction between fatty acid and the bifunctional compound. The alteration in the structure of the treated fabric was assigned using XRD, FTIR, SEM analyses. The comfort characteristics as well as mechanical properties of the treated fabrics were also investigated. Preliminary results indicate that the prepared condensate is a suitable candidate for improvement of comfort characteristics of acrylic fabrics without any adverse effect on its inherent properties.
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There is a dearth of machine-learning investigations of the micro-mechanics of granular soils. The micro-mechanics deals with the mechanics of granular materials at the micro-scale (often particle scale) or meso-scale and is contrasted with the macro-mechanics which focuses on the macro-scale behavior measured at the laboratory sample scale or field scale. In this talk, a poineering investigation of the micromechanics in quasi-statically sheared granular materials using machine learning methods is conducted. An artificial neural network (ANN) based on discrete element method (DEM) simulation data is developed and applied to predict the anisotropy of contact force chains (CFC) in an assembly of spherical grains undergoing a biaxial test. An excellent model performance manifested in a close match between the rose diagrams of CFC from the ANN predictions and DEM simulations is obtained. In addition, some preliminary results of the prediction of the constitutive response of granular materials using the machine learning method are also presented.
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Lead zirconate titanate, PbZr.52Ti.48O3, nano-powder has been synthesized via simple procedures based on the Pechini-type reaction route method. Laser radiation was applied during the preparation process. The influence of the laser radiation on the obtained nanopowders was studied. The thermal behavior of the dried gel was investigated via thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The obtained powders were characterized via XRD, UV–VIS–NIR, FT-IR, SEM and TEM techniques. The obtained X-ray powder diffraction patterns were analyzed by MATCH software to identify the existing phases, then a profile fit was carried out using the FullProf software package. The Goldschmidt tolerance factors and modified tolerance factors were estimated for the prepared nanopowders while the fractional of the observed individual phases were evaluated via the Rietveld method. The XRD measurements and TEM images confirmed the formation of nanoparticles. Williamson– Hall (W–H) and size strain plot (SSP) methods were used to evaluate the crystallite size and the lattice microstrain of the calcined nanopowders. The optical band-gap energy was determined using diffused reflectance measurements and the transformed Kubelka-Munk function. The band-gap energy values of the synthesized nanopowders were found to be slightly changed when laser radiation was applied.
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This work presents a simple, inexpensive, and highly sensitive electrochemical sensor based on new polymeric membrane incorporating kinetin (6-furfurylaminopurine) as a specific sensitive molecule deposited on the surface of a glassy carbon electrode for the detection of cadmium in water. The electrochemical characterization was examined using electrochemical impedance spectroscopy and cyclic voltammetry. Additive effect and selectivity for cadmium over many common cations, such as copper, lead, and zinc, at pH 4.5 are studied. We showed that the cadmium selectivity is better for membrane based on potassium tetrakis(4-chlorophenyl)borate (KTpClPB) with a significant decrease of the Rct and an increase in constant phase element CPE, the sensor exhibits a LOD of 3,96×10- 10 M with a linear response towards cadmium ions over a wide concentration range of 10-6 to 10-9 M. vFinally, the proposed sensor was applied to the determination of cadmium in water and can be proposed to use successfully in real water samples.
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Graphene-based nanomaterials (GBNMs) are widely used in various industrial and biomedical applications. GBNMs of different compositions, sizes and shapes are being introduced without thorough toxicity evaluation due to the unavailability of regulatory guidelines. Computational toxicity prediction methods are used by regulatory bodies to quickly assess health hazards caused by newer materials. Due to the increasing demand of GBNMs in various sizes and functional groups in industrial and consumer-based applications, rapid and reliable computational toxicity assessment methods are urgently needed. In the present work, we investigate the impact of graphene and graphene oxide nanomaterials on the structural conformations of small hepcidin peptide and compare the materials for their structural and conformational changes. Our molecular dynamics simulation studies revealed conformational changes in hepcidin due to its interaction with GBMNs, which results in a loss of its functional properties. Our results indicate that hepcidin peptide undergo severe structural deformations when superimposed on the graphene sheet in comparison to graphene oxide sheet. These observations suggest that graphene is more toxic than a graphene oxide nanosheet of similar area. Overall, this study indicates that computational methods based on structural deformation, using molecular dynamics (MD) simulations, can be used for the early evaluation of toxicity potential of novel nanomaterials.
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Complexes of phthalocyanines with metals are known as the compounds with promising properties such as high chemical and thermal stability, as well as unique optical and electrical ones. The nature of the central metal ion and substituents are a tool for fine-tuning the physicochemical characteristics of compounds. The disadvantages of phthalocyanines associated with low solubility and a tendency to aggregation can be overcome by chemical modification of the macrocycle periphery by introducing functional- substituents. In this regard, this work is devoted to the synthesis and study of properties of 4-(2/4-cyclohexylphenoxy)phthalonitrile as well as phthalocyanine based on it and its complexes with s, d and f- metals. One of the simple and effective methods for obtaining phthalocyanines is a nitrile one. Initially, 2-cyclohexylphenoxy– and 4-cyclohexylphenoxy phthalonitriles were obtained, which afterward being used for the synthesis of corresponding phthalocyanines and their metal complexes. Complexes with s- and d- metals synthesis were carried out by template fusion of substituted nitriles with appropriate metal salts at 180-190 оС. The preparation of metal complexes with f- elements was carried out by boiling phthalonitriles with metal acetates in boiling iso-amyl alcohol in the presence of DBU. All synthesized compounds were isolated and purified using column chromatography. The identity of all the compounds obtained characterized by 1H NMR, IR spectroscopy and elemental analysis. Due to the good solubility of the synthesized compounds in organic solvents, their spectral and luminescent properties were studied. The effect of the nature of the metal and solvent on the position of the main band and the behaviour of the spectral curves is shown. This work was carried out with the financial support of the Russian Science Foundation (Grant No. 17-73-20017) using the resources of the Center for Collective Usage of the ISUCT.
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During a severe accident occurring in a nuclear power plant, many Fission Products (FP) are released from the degraded fuel and transported in the Reactor Coolant System (RCS). This was the case for the Fukushima Daiichi (FD) accident with important FP releases. One of the main FP found around the FD power plant after the accident was iodine. If early phase releases were well predicted by SA simulation codes, delayed releases were not correctly predicted1,2,3. Such discrepancies are attributed to the deposits revaporization composed of metallic iodide (CsI, CdI2, AgI…) inside the RCS which were not yet modeled in the SA simulation tools. Cadmium iodide revaporization behavior was investigated experimentally, mixed with CsI4 and by DFT calculation5 highlighting possible revaporization as cadmium oxide and molecular iodine (I2). However, up to this day, no specific analytical study on revaporization of cadmium iodide in isotherms conditions and depending on oxygen concentration has been performed. This study is scheduled within the OECD/ NEA/ESTER project. The present work aims at determining the CdI2 revaporization mechanism and quantifying revaporized species in isotherm conditions (temperature between 200 and 400°C) and oxygen partial pressure (between 1.10-4 and 4.10-2 atm). Thanks to a new experimental setup coupled with ICP-MS, Tof-SIMS and XPS analyses, Cd and I speciation are determined and quantified. On the one hand, with a steam/air atmosphere (oxygen partial pressure at 4.10-2 atm) significant I revaporization is observed even with isotherms at 400°C resulting in the transport of both gaseous and aerosols I species. On the other hand, when oxygen partial pressure increases, I gaseous species revaporization increases with different iodine species.
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Currently, the Russian Federation is completing the construction of a Pilot Demonstration Center (PDC) for the innovation-based spent nuclear fuel (SNF) of VVER-1000 treatment. Minimization of the generated liquid radioactive waste volume is one of the most important PDC tasks. To implement this approach VNIINM has developed a scheme for SNF processing using new technological and instrumental solutions (Figure 1). According to the technological scheme, uranium, plutonium, and relevant elements are extracted from the nitric acid solution. Then the extract is scrubbed, plutonium is back-extracted with a part of uranium, and then the uranium extract is stripped from the remains of plutonium, neptunium, and technetium. Plutonium (III) in the solution of back-extraction is oxidized to plutonium (IV) and is extracted again together with U. The extract of the second stage is then scrubbed and plutonium is back-extracted. The first back-extraction of plutonium with a part of uranium is carried out in a mass-transfer separator by an aqueous stream containing Pu (IV) and Tc (VII) reducing agents at a high organic phase/aqueous solution ratio (up to 30). Additional purification of the uranium extract is carried out by a weakly acidic solution of the complexone. The spent complexone solution is directed to the U-Pu extract scrubbing stage. Then the plutonium-technetium solution goes through a catalytic oxidation column with a carbon catalyst. The oxidized Pu-Тс solution is directed to the refining unit. A complex test of the VNIINM scheme of the VVER-1000 SNF reprocessing was successfully carried out in a PDC hot cells using a simulator of plutonium solution as well as the solution of spent nuclear fuel of the thermal reactor. The main technological indicators of the scheme and high efficiency of the mass-transfer separators usage have been confirmed. The feasibility of the two-stream input of the circulating solvent to the head extraction unit and the process of a two-stage U and Pu separation with a concentrated plutonium solutions obtaining at the first stage has been confirmed, as well as the process of additional U-extract purification from plutonium residues at the second stage with the spent scrubbing solution utilization inside the extraction cycle. The efficiency of the catalytic oxidation of Pu (III) → Pu (IV) process without the introduction of additional oxidizing reagents has been also confirmed. The efficiency of the refining plutonium sub-cycle unit with the return of excess uranium to the technological scheme with a return organic flow is shown.
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Recently, quantum dots (QDs) are fnding enormous application in white light emitting diodes (WLEDs) and WLEDs with high color rendition are in high demand. QD-WLEDs use diferent color (Red, Blue, Green) emitting QDs to obtain white light. Use of diferent color emitting QDs afect purity of white light due to self-absorption losses and QD degradation, in the long run afecting color rendering index (CRI) of WLEDs. Herein, we report low cost, environment friendly, open air atmosphere synthesis of single system white light emitting carbon dots (CDs) with broad emission bandwidth ranging 116 –143 nm and quantum yields (QY) ~ 5 – 13 % in colloidal state by modifying CD surface. Furthermore, carbon dot polymer phosphor (CD-PDMS phosphor) is fabricated which emits white light under UV illumination with a record emission bandwidth of ~ 154 nm and QY~ 16 % in solid state. Moreover, CD-PDMS phosphor exhibit excellent color rendering index (CRI)~ 96, the highest reported so far with CIE co-ordinates (0.31, 0.33) that are quite akin to pure white light. Such high performances are achieved due to high quality of CDs and CD-PDMS polymer phosphors by precise control in passivation/functionalization of nanoparticle surface. This work will set platform for the application of CD-phosphor based WLEDs in lighting systems.
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The development of a hand-held device utilizing laser-induced breakdown spectroscopy (LIBS) has revolutionized the elemental analysis of solid samples, since it can be used in-the-field for geological and mineralogical exploration. The increasing need for lithium, precious metals, and rare earth elements for the manufacture of electronic gadgetry has spurred this endeavor. Our full LIBS spectra from 190-950 nm of over 75 elements were obtained and used to confirm the presence of those elements in a large number of mineralogical samples, the metals present in antique and souvenir spoons from all over the world, in jewelry, coins and other alloyed objects. Detection of non-metals in samples has been challenging, since the intensity of their emission lines are often at least two orders of magnitude smaller than the intensity of metal emission lines. We determined the relative intensity ratios of halogen/alkali metal in 20 alkali halide samples in order to develop a method to aid in confirming the presence of Cl, F, Br and I in mineralogical samples. How to confirm the presence of sulfur in solid samples will be illustrated. LIBS (in particular the hand-held device), is a valuable addition to our arsenal of analytical techniques for elemental analysis of myriad solid samples.
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Incorporation of nanomaterials and nanostructures into sensors causes remarkable advances in device operation due to sensitivity, selectivity, multiplexed detection capability, and portability. In this study, a nanographene sensor coated with gold nanoparticles and tripeptide Gly–Gly–His was designed for Cu2+ ion detection at low concentrations. Graphene oxide synthesized by the modified Hummer’s method and analyzed by UV–Vis spectrometry, x-ray diffraction (XRD), and transmission electron microscopy (TEM). The optimum conditions based on the maximum gold loading were evaluated 71 min for incubation time and 1 for HAuCl4/ HEPES concentration ratio. Gold-coating on graphene oxide was approved by TEM, UV– vis spectrometry, XRD, and FTIR. The EDC/ Sulfo-NHS method was used to stabilize Gly-Gly-His to graphene oxide-gold, which has a high affinity toward Cu. The performance mechanism of this nanosystem was based on the localized surface plasmon resonance (LSPR) property of gold nanoparticles. The sensor was extremely selective and sensitive to Cu2+ with the detection limit of 8.83 nM without cross-binding to other metal ions. The response time was evaluated about 9 min. The GO-Au-GGH biosensor was also very stable and easily reused, which further confirms it as an efficient and sensitive Cu2+ ion detection device.
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In this study, malathion and chlorpyrifos degrading bacteria were isolated from agricultural soil samples taken from the Himachal region in India. A total of 52 organisms were isolated which were further screened for their efciency for chlorpyrifos and malathion degradation. Screening was done by checking the growth on Nutrient Agar, Mineral Salt Medium and MacConkey agar plates containing chlorpyrifos and malathion; 37 isolates showed growth in these. Biomass assay and minimum inhibitory concentration (MIC) determination were carried out for the selection of most efficient bacterial isolates. Out of the seven isolates which showed good biomass assay and MIC, only three isolates (PDM-2, PDM-15 and PDM-20) were selected for further studies. These were characterized by various biochemical tests, Gram staining, indole test, methyl red test, Voges-Proskauer test, citrate utilization test and carbohydrate fermentation test. Out of three isolates, PDM-15 showed good resistance against the antibiotics such as erythromycin, chloramphenicol, ampicillin and penicillin and identifed as Kocuria assamensis. Degradation of 71.3% of chlorpyrifos and 85% of malathion was observed by the gas chromatography. Nowadays, the problem of pesticides pollution is increasing and it causes the environmental hazard. Microorganisms are essential for bioremediation of environmental pollutants because they play a considerable role in the degradation of insecticides. The strain with good degradation capability, i.e. Kocuria assamensis was isolated from agricultural soil of diferent regions of Himachal Pradesh. It has shown that this strain was able to grow in the presence of chlorpyrifos and malathion and it utilized these pesticides as carbon source. Results obtained in this study have shown that the isolate PDM-15 was found to be Gram-positive coccus and was identifed as Kocuria assamensis which was capable of degrading pesticides and tolerating antibiotics as well as metal ions.
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GIS-technology facilitated the study of organochlorine pesticides’ (hexachlorobenzene, hexachlorocyclohexane and DDT) distribution in the Barents Sea bottom sediments. The study aims at reviewing the pesticides’ distribution in the sediments and the ways they are transported in the Barents Sea. The results from the analysis of samples of the sediments’ upper layer at 696 stations were processed. The sampling was conducted in 2003-2019 during research cruises of PINRO named after N.M. Knipovich. The pesticides were identified by using the chromatography/ mass spectrometry instrument and applying the capillary gas chromatography method. Mapping was done in the ArcGIS application environment. There were additionally six sites identified: the Spitsbergen a shelf area south of Spitsbergen, the Bear Island Trough region including the Hopen Trench, The Northeast area, the Southeastern area (the Pechora Sea), the Eastern (Central) Basin and the Kola Bay region. There was separate statistical data processing conducted for each site. The pesticides contents in the sediments were compared between the sites and the Barents Sea in general. During the study, there were maps made of the distribution of the pesticides in the Barents Sea sediments. The sediments of the Eastern Basin and the Bear Island Trough sites were identified as the most contaminated by the organochlorine pesticides in the Barents Sea, with the average total content of 5.86 and 4.36 ng/g of dry weight respectively. The sediments of the Barents Sea southeastern part were found to be the least contaminated, with the average content of 1.53 ng/g of dry weight. Long-distance trans-border transfer, contaminants coming from the Arctic due to melting pack ice and glaciers on the Spitsbergen archipelago, the Franz Josef Land archipelago and Novaya Zemlya (long-term accumulated contamination) are likely the main sources of the sediments contamination by pesticides in the northern part of the Barents Sea.
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GIS-technology facilitated the study of organochlorine pesticides’ (hexachlorobenzene, hexachlorocyclohexane and DDT) distribution in the Barents Sea bottom sediments. The study aims at reviewing the pesticides’ distribution in the sediments and the ways they are transported in the Barents Sea. The results from the analysis of samples of the sediments’ upper layer at 696 stations were processed. The sampling was conducted in 2003-2019 during research cruises of PINRO named after N.M. Knipovich. The pesticides were identified by using the chromatography/ mass spectrometry instrument and applying the capillary gas chromatography method. Mapping was done in the ArcGIS application environment. There were additionally six sites identified: the Spitsbergen a shelf area south of Spitsbergen, the Bear Island Trough region including the Hopen Trench, The Northeast area, the Southeastern area (the Pechora Sea), the Eastern (Central) Basin and the Kola Bay region. There was separate statistical data processing conducted for each site. The pesticides contents in the sediments were compared between the sites and the Barents Sea in general. During the study, there were maps made of the distribution of the pesticides in the Barents Sea sediments. The sediments of the Eastern Basin and the Bear Island Trough sites were identified as the most contaminated by the organochlorine pesticides in the Barents Sea, with the average total content of 5.86 and 4.36 ng/g of dry weight respectively. The sediments of the Barents Sea southeastern part were found to be the least contaminated, with the average content of 1.53 ng/g of dry weight. Long-distance trans-border transfer, contaminants coming from the Arctic due to melting pack ice and glaciers on the Spitsbergen archipelago, the Franz Josef Land archipelago and Novaya Zemlya (long-term accumulated contamination) are likely the main sources of the sediments contamination by pesticides in the northern part of the Barents Sea.
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Investigation in solution exhibits the interest of chemist in thermodynamic aspects, which include knowledge of the stability constant of complexes with ligands of biochemical interest. It has been relevant for the experimental modeling of both reactions of metal ions with biomolecules and non-covalent interactions occurring in biological system. Stability constant data have been utilized to compute the equilibrium constant of ternary and quaternary complexes of citrulline/ tryptophan and thymine with Cu(II), Zn(II) Co(II) and Ni(II) using SCOGS computer program at 37±1°C and in ionic strength I=0.1 M NaNO3. The metal–ligand formation constant of MA, MB, MAB and M1M2AB type of complexes follows Irving William order. The distribution curves of various complex species occurring at the different physiological pH have been discussed, and solution structures with an explanation of plausible equilibria have been proposed.
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The adsorption cycles are employed in cooling as well as in desalination industries due to its many advantages including waste heat utilization, solar thermal energy application and low maintenance cost. The major bottleneck in conventional adsorption cycles commercialization is its large footprint due to poor heat transfer in adsorbent packed bed heat exchangers. The recent development in coating technologies enabled powder adsorbent to be coated on heat exchanger to improve heat transfer and reduce the footprint of adsorption cycle. We designed an adsorption cycle based on adsorbent coated heat exchanger to investigate the two major parameters such as, the best binder suitable with most commonly silica-gel adsorbent and reliability of adsorbent and binder for commercial applications. The initial experimental investigation showed that silica-gel and hydroxyethyl cellulose (HEC 3% by weight) binder improved the overall heat transfer coefficient to 100-120W/m2-K as compared to 30-40W/m2-K in conventional packed bed AD cycle. In terms of pore surface area, the HEC only block 5-10% of total adsorbent area that showed insignificant impact on performance. We also developed detailed mathematical model to simulate adsorbent coated bed AD cycle performance and to compare with experimental results. Both have good agreement in terms of heat transfer coefficient values. It can be concluded that, the proposed coated bed AD cycle can produce double the amount of desalinated water or cooling effect with same amount of waste heat available.
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Preventive tests and diagnosis of in-service power transformers require system outage and need experts’ knowledge and experiences in interpreting measurement results. Techniques such as insulating oil analysis may cause significant variance to measurement results due to different practices in oil sampling, storage, handling and transportation of insulating oil. The principal objective of this thesis is to develop a cost effective, fast, and reliable measurement technique for incipient fault analysis of in-service power transformers. An extended application of Polarization and Depolarization Current (PDC) measurement for characterization of different fault conditions of in-service power transformer was investigated in this research. The unique characteristic pattern of each condition was determined by a unique numerical dimensionless quantity known as the Depolarization Ratio Index (DRI) to express the changes of depolarization current shape. In addition, a graphical representation of DRI was also used as a technique to identify the incipient fault. Changes in the molecular properties of the insulating oil material due to different fault conditions were found to influence the initial time response. Sensitivity analysis using Artificial Neural Network (ANN) indicated that depolarization current provided better accuracy in identifying and classifying different transformer conditions as compared to the polarization current. A range of DRI between 5/100 and 10/100 was found to have a correlation of at least 90% with the incipient fault in power transformer. A DRI of 5/100 was observed to have a higher accuracy when detecting units with normal, overheating, and arcing conditions, compared to that for partial discharge condition. Both DRI and its graphical representation were validated using fresh field data and were more than 90% accurate. Both were able to identify and correctly classify the transformer condition as normal, overheating, or arcing. This demonstrated that the PDC measurement technique can be used to determine incipient faults in a power transformer.
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The report is devoted to the features of sorption properties of magnetite with respect to hexavalent chromium ions and the possibility of its use as a sorbent for removing these toxic ions from contaminated aqueous solutions. It has been shown that during the sorption of chromium(VI) ions by magnetite, two processes occur simultaneously: ordinary adsorption and chemisorption (redox reaction between hexavalent chromium ions and magnetite). The latter is accompanied by the oxidation of iron(II) in magnetite to iron(III) and the reduction of chromium(VI) ions to chromium(III) with the formation in the surface layer of magnetite (or on its surface) maghemite and a number of other compounds, including mixed chromium compounds(III) with iron. It is shown that the kinetics of the redox process between chromium(VI) and magnetite is described by the first-order reaction equation with respect to the concentration of chromium(VI) ions in solution. The parameters of the equation are found. As a result of chemisorption, unlike conventional sorbents, irreversible binding of chromium(VI) to magnetite occurs, which excludes the re-entry of its ions into the environment. In this case, the sorption capacity of magnetite, as it is saturated with chromium, irreversibly decreases. In addition, the sorption capacity of magnetite with respect to chromium(VI) ions also decreases with increasing pH of the solution being purified, and at pH>11 it is practically zero.
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In order to provide experimental guidance, a theoretical study was performed on transparent conduction oxide (FTO)/TiO2/ interface defect layer 1/CH3NH3SnI3/interface defect layer 2/Cu2O/ back contact solar cell. The simulation was performed under the illumination of 1000 W/m2, at 300 K and an air mass of AM 1.5G. The diffusion lengths of electron and hole were set to 260 nm and 560 nm in absorber layer, respectively. The set value is very near to recently observed experimental values. The device performance is severely influenced by the thickness of absorber layer, acceptor density, defect density and work function of various back contact electrode materials. Oxidation of Sn2+ into Sn4+ was considered and it is found that the reduction of acceptor concentration of absorber layer significantly improves the device performance. Further, optimizing the defect density (1014 cm−3) of the perovskite absorber layer, encouraging results of the Jsc of 40.14 mA/ cm2, Voc of 0.93 V, FF of 75.78% and PCE of 28.39% were achieved. This theoretical simulation provides an appropriate direction for developing photovoltaic technology.
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Introduction: An in vitro study was conducted to evaluate the surface roughness produced by two different methods: hand-held mechanical and air-rotor stripping and also by HORICOR and Ortho Organizer strips, before and after polishing with 3M Sof-Lex™ Finishing Strips under Atomic Force Microscope. Methodology: Study included 44 proximal surfaces of extracted premolars divided into control group and three experimental groups with 12 surfaces in each. Hand held mechanical stripping was done by forty passages of 6cm long abrasive strips and Air-rotor stripping using high-speed air-rotor turbine hand piece. Polishing was done using 3M Sof-Lex™ finishing strips. Reduced teeth samples were viewed under AFM and the proximal strips under Confocal microscope for surface roughness. Results: Air-rotor stripping produced more surface roughness compared to mechanical reduction technique (P = 0.009). There was no significant difference between the roughness produced by two different proximal strips. Tooth surface after IPR with polishing had less roughness compared to unpolished surface. There was no mean difference between the wear of proximal strips (Fig 1). Conclusion: The mechanical reduction technique of interproximal surface produces less surface roughness compared to air-rotor stripping. Polishing with 3M Sof-Lex strips after reduction irrespective of the technique and material used gives smoother surface than even normal enamel.
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The oxygen-evolving complex of photosystem II (PSII) in green-plants, where water oxidation takes place, is the fundamental element of photosynthesis, where sunlight is transformed into renewable chemical energy. Prior studies led to the discovery of highly effective, molecular, homogenous catalytic systems of noble metals such as Ru or Ir. Nevertheless, their high cost, toxicity, and low abundance are unfavorable for using them as bulk water oxidation catalysts (WOCs).1,2 Hence, switching focus to environmentally benign, thermally stable, oxidatively robust, and redox-active Mn-substituted polyoxometalates (POMs) are of special interest, also due to the nature of the active center of PSII. Along these guidelines being inspired by nature with the principal aim to design new and efficient oxidation systems employing natural O2 as primary oxidant, a novel Mn-substituted POM was tested as artificial photosynthetic WOC [MnIII3MnIVO3(CH3COO)3(A-α-SiW9O34)]6- (Mn4POM), using the RuII(bpy)32+ (P) / Na2S2O8 sacrificial cycle,1,2 and was found to be active with higher turnover number and frequency than amorphous Mn-based oxides.
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The thermal and physicochemical characteristics of the husk of rice, pineapple, banana, potato, papaya, and lettuce were studied to evaluate their effectiveness in a composting process as a harvesting alternative. Thermogravimetry (TGA) was used to assess the thermal stability of the shells, mass spectrometry (MS) to identify volatile compounds, differential scanning calorimetry(DSC) to find the possible phase transitions caused by the increase of temperature, and elemental analysis to determine the C/N ratio. In the composting process, four mixtures were made through the quantitative balance of nitrogen, carbon, and humidity,and the process was controlled and monitored until the compost was obtained. The results in the TGA showed three characteristic stages present in organic materials that absorb heat: the dehydration of the samples in a temperature range between 25and 230 °C, the decomposition in a range of temperatures that occurred between 240 and 370 °C, and degradation in a temperature range between 380 and 600 °C. DSC showed the endothermic processes were associated with melting followed by the evaporation of the aqueous content, and decomposition and a degradation of the samples associated with volatile contents. The exothermic processes were associated with the oxidation of the elements released during evaporation of the aqueous content, and the enthalpies of the processes varied between 5.90 and 91.60 J/g. Mass spectrometry identified that the volatile compounds released were H2O, CO2,CO,CH4, and N. In the composting, the effective mixture was a 20% concentration of each of the bio-wastes that demonstrated better conditions for decomposition, where alkaline pH and acid indicated the decomposition of fatty acids, nitrogen, and carbon. Finally, it was concluded that the thermal stability of the shells is associated with the presence of lignin, cellulose, and hemicellulose. In addition, the compost obtained is a fertilizer applicable to soils and plants.
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The purpose of this paper is to describe a possible best practice to teaching environmental chemistry from a humanitarian engineering perspective using microchemistry equipment. The interest in teaching chemistry by focusing on humanitarian engineering arises from the economic and environmental concerns that the country of this study faces, some of which are poverty, climatic changes, food crisis, inadequate health care, water crisis and pollution. As an educator, there is an interest in educating future generations to be able to cope with environmental changes that face their countries and the world at large. This exposition of a possible new approach, with appropriate pedagogies that is presented here may be an answer that under-developed, developing and emergent economies may adopt to close the gap between themselves and other industrialized nations. A case of a study where a topic in an environmental study course is presented. The theoretical framework2 which supported the study in which 19 students were involved was constructivism1. Findings indicated that teaching humanitarianism and humanitarian engineering through chemistry education in an integrated manner through student-centred approaches3 had massive potential.
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Intellectual disability (ID) is still unexplained in 60% of cases and prenatal diagnosis is very challenging for this condition. A second gravida presented to us at 6weeks of gestation for counselling. Her previous child had been diagnosed with intellectual disability and autism. A detailed family history showed that her brother also had intellectual disability. Screening investigations were normal for affected child. Exome sequencing report revealed variation of unknown significance (VOUS) on SIN3A gene and UPF3B gene. The variation in X linked UPF3B gene was reclassified as novel pathogenic variation after segregation studies with parents and affected maternal uncle for both the genes variations. An amniocentesis was done at 18 weeks gestation for the novel mutation in UPF3B gene and fetus was found unaffected. Patient delivered a healthy male child who is doing well at two years of age. To conclude, we should not disregard VOUS on exome sequencing. Identification of VOUS requires careful genotype phenotype correlation and segregation studies to counsel parents regarding risk of having another affected child.
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Natural products contain pyran moiety have interesting biological and pharmacological activities. The structural importance of the pyran class of organic molecules and the effectiveness of this kind of molecules as corrosion inhibitors have prompted their recognition by the chemistry network as privileged structures. This present article aimed to synthesize pyran derivatives namely ethyl 2-amino-4-(4-hydroxyphenyl)- 6-(p-tolyl)-4H-pyran-3-carboxylate (HP), ethyl 2-amino-4-(4-methoxyphenyl)-6- (p-tolyl)-4H-pyran-3-carboxylate (MP) and ethyl 2-amino-4-(4-hydroxy-3,5- dimethoxyphenyl)-6-(p-tolyl)-4H-pyran-3- carboxylate (HDMP) and characterized by FTIR, NMR and Mass spectroscopy. Weight loss and electrochemical measurements were done to study the corrosion mitigation of mild steel (MS) in 1M sulphuric acid solution and their adsorption followed Langmuir isotherm. Polarization measurements showed the inhibitors act as mixed-type. Surface of the metal with and without inhibitors in acid medium was studied by SEM-EDS, XRD and AFM methods. Quantum chemical studies have been performed for the non-protonated and protonated forms of the inhibitors. The obtained results by MD simulations have revealed that the studied molecules bind onto iron area spontaneously with binding energies of 438.465 kJ/mol, 434.934 kJ/mol, and 456.854 kJ/mol for HP, MP and HDMP respectively.
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Use of sewage sludge (SS) in crop production is a feasible strategy for its disposal however, its application may pose an adverse impact on soil and human health. Therefore, identification of permissible level of SS is essential to prevent soil contamination. This research not only evaluated the impact of SS application on spinach (Spinacia oleracea L.) biomass yield but also tracked the accumulation of heavy metals in soil and plants. A pot experiment was conducted on Inceptisol with different levels of SS (0, 5, 10, 15, 20, 25, 30, 35, and 40 t ha-1) with recommended dose of fertilizers (RDF). Applications of SS at 20 t ha-1 resulted, the highest biomass yield however, the concentration of zinc (Zn) and cadmium (Cd) has exceeded the safe limit in leaves. Heavy metals accumulation in the plant was the highest in SS at 40 t ha-1. Spinach grown at 20 t ha-1 and higher dose of SS exceeded the safe limit of Zn and Cd concentration in leaves and translocation factor (TF) of lead (Pb) and Cd was found to be > 1. Hazard quotient (HQ) of Pb > 1 at higher doses of SS indicate health hazard if spinach is used for consumption. Assessment of health risk showed that, there was a possibility of Pb hazard at a high dose of SS (HI > 1). Evaluation of various soil pollution indexes revealed that the addition of SS enhanced the buildup of Cd and chromium (Cr) in soil. This study advocated the use of SS at 10 t ha-1 to sustain soil quality with no risk of food chain contamination.
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Carbon black is traditionally used in tires as filler, but it possess a major challenge of CO2 emission during manufacturing stage. In the past few decades, the focus has been shifting on silica fillers to develop low rolling resistance tires resulting in low CO2 emissions contributing thus establishment of healthy eco system. In the present study Silica is used as a filler to reduce the amount of Carbon. Materials that can impact the wet traction, rolling resistance and dry traction of a silica filled compounds are studied by varying six different factors i.e SSBR Rubber, Silica, Carbon Black, Zinc Oxide, CBS and DPG in recipe. Use of eco-friendly filler, silica in compound reduced the carbon foot print of vehicle. One can observe here that Green tyres have RR very lower than conventional one, with low rolling resistance vehicle requires less force to move forward and hence less fuel will be consumed thus decreasing carbon dioxide emissions and ultimately its carbon footprint will also be decreased. The main hurdle for tire designers in green tyre manufacturing is to tradeoff between the dry traction and rolling resistance values, while here we can observe through our research that various compounds have DT values comparable with that of conventional tyres. Green tires have improved wet grip compared to conventional tires. Thus it will prevent the skidding of vehicle on wet surface hence increasing its safety.
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Limestone was used to modify the fluxing action of two potash feldspars (a pure potash feldspar and a sodo-potash feldspar) labelled P and C respectively in the formulation of porcelain stoneware based on Cameroonian raw materials. The effect of limestone addition (0 to 10 wt. %) was investigated in the range of sintering temperature between 1125 and 1300°C. Characterization of sintered samples including thermal behavior (DTA, TG and dilatometry test), phase evolution, densification parameters, flexural strength, morphology as well as pores structure were investigated in details. The maximum flexural strength (138 MPa) was obtained at 1175°C with P series (7 wt% addition of limestone) and at 1200°C (122 MPa) for C series. The maximum density (≈ 3.1g/cm3) and lower water absorption (≈ 0%) were obtained at 1200°C. Mullite and anorthite were identified as main crystalline phases. Starting from 1175°C and mostly at 1200°C, the two series compositions (with 7wt% addition) presented a self-glazing phenomenon which gave them significant brightness and high aesthetic quality; these properties were accomplished only at 1300°C for reference samples with no lime addition (P0 and C0). A proper addition of limestone (3 to 7wt. %) with potash feldspar, significantly reduced the sintering temperature (~150°C) and permits the production of high strength (122 – 138 MPa), low energy and sustainable porcelain stoneware.
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Background: Fragmented cytokeratin 18 (fCK18) released from epithelial cells undergoing apoptosis is widely studied in various diseases. However, fCK18 measurement is not utilized in clinical practice due to imprecise disease-state cutoff values. Therefore, we generated new monoclonal antibodies (mAbs) and developed a highly sensitive chemiluminescent enzyme immunoassay (CLEIA). Methods: Capture (K18-624) and detection (K18-328) mAbs were generated from mice immunized by either a synthetic peptide or a commercial recombinant protein. The mAb characterization was performed using immunoblotting, immunoprecipitation and reactivity with synthesized peptides. A recombinant fCK18 (rfCK18) produced in Escherichia coli was purified by affinity column chromatography. Analysis of performance and measurement of human fCK18 were evaluated using K18-624 and K18-328 in a highly sensitive CLEIA. Results: K18-624 had a high binding ability compared to the current commercial antibody. K18-328 recognized 323S-340G of CK18. A rfCK18 was expressed in the soluble fraction of E. coli when the N-terminal region (260 amino acid residues) of CK18 was truncated. Based on the fCK18 CLEIA performance, the coefficients of variation (CV) for within-run and between-day repeatability were below 10% and the recoveries were in the range of 15%. The detection sensitivity was 0.056 ng/mL. Serum fCK18 levels were significantly increased in NASH patients when compared to healthy individuals. Conclusions: Our new fCK18 mAbs showed high affinity and sensitivity. CLEIA using our new antibodies will be useful in measuring fCK18 in human blood thereby generating accurate clinical diagnoses of human liver diseases.
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New algorithm is presented for selective identification such gases and vapors in the air as hydrogen, methane, propane, ethanol, acetone etc by use of ZnO and SnO2 based sensors doped with PdO and La2O3. The conductivity responses Δσ(μS) vs z=1000/T (K-1) from temperature modulation process are interpolated by following parameterized l discriminating functionswhich parameters are estimated via nonlinear regression method. The dependences of the principal ones Ai(CY) on analyte Y concentration CY compose multivariate calibration portrait fitting to which an unknown analyte X is identified as the Y (e.g. ethanol in dry air— Fig). And the common abscissa of all intersection points of the level lines AiX and calibration curves Ai(CY) defines the analyte concentration in the units used (mg/m3, Fig). In case the abscissas are different or some of them are missing the analyte X is not Y. The method allows selective detection of broad list of analytes in synthesized dry and real wet air and even distinguishes the substances of the same homological group: methane/ propane/ hexane and ethanol/methanol/isopropyl alcohol. Actually, the method is breakthrough in solving the very important problem among 3S-problems:selectivity, stability, sensitivity.
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It is known that highly charged droplets formed in the course of electrospraying disintegrate into a number of smaller droplets. The criteria for the instability and disintegration of conducting liquid droplets in the course of electrospraying have been considered in this study. The development of charge instability may lead to the formation of droplets with a complex nontrivial shape. Some forms of the perturbation of a spherical liquid droplet have been shown for the case when the Rayleigh stability criterion is exceeded. The energy of droplets having complex shapes has been studied. The calculations were performed within the Wolfram Mathematica package using the numerical integration and iteration methods. The study of the development of the charge instability has given a new result: it has been shown that a quasi-stable state may exist during the disintegration of a liquid droplet at Rayleigh parameter values exceeding the critical one. A new non-spherical droplet shape has been found, for which the disintegration process is very slow, and the magnitude of the change in the energy is almost equal to zero.
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Research studies about nanofluids are on the rise owing to the mounting interest and demand for nanofluids as heat transfer fluids in a wide variety of applications in recent years. The stability of nanofluids is one key challenge hindering the widespread practical application of nanofluids. Studies showed that stability depend on pH, sonication time, different types of shapes, and sizes of nanoparticles with different base fluids, nanofluid preparation methods, volume fractions, and surfactants as well as functionalizing. The incorporation of nanoparticles in the base fluid leads to change in the thermophysical properties such as thermal conductivity, viscosity, and specific heat that affect the convective heat transfer. Several factors affecting the thermo-physical properties; including types of nanoparticles, solid volume fraction, different base fluid, stability, temperature, particle size, shape, pH, sonication, and surfactants. There are many contradictory results found in the literature on the influence of effective parameters on thermophysical properties. It has been observed that the thermophysical properties are affected by the mentioned parameters. The recent development in this field indicates that the application of nanofluid in this thermal system showed promising performance. Proper characterization of nanofluids (with hybrid nanofluids as well recently) results in more efficient heat transfer fluids compared to single nanoparticle-based nanofluid. However, more intense research is needed towards the selection of proper hybrid nanoparticles, their preparation, characterization, and long-term stability to exploit their full potential. Finally, various application areas of nanofluids, such as transportation, electronic cooling, energy storage, mechanical applications, solar energy etc. are discussed.
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Sugarcane (Saccharum officinarum L.) is a cash crop grown commercially for its higher amounts of sucrose, stored within the mature internodes of the stem. Quality and yield of sugarcane production is always threatened by the damages of cane borers and weeds. In current study two problems were better addressed through the genetic modification of sugarcane for provision of resistance against insects and weedicide via the expression of two modified cane borer resistant CEMB-Cry1Ac (1.8kb), CEMB-Cry2A (1.9kb) and one glyphosate tolerant CEMB-GTGene (1.4kb) genes, driven by maize Ubiquitin Promoter and nos terminator. Insect Bio-toxicity assays were carried out for the assessment of Cry proteins through mortality percent of shoot borer Chilo infuscatellus at 2nd instar larvae stage. During V0, V1 and V2 generations young leaves from the transgenic sugarcane plants were collected at plant age of 20, 40, 60, 80 days and fed to the Chilo infuscatellus larvae. Up to 100% mortality of Chilo infuscatellus from 80 days old transgenic plants of V2 generation indicated that these transgenic plants were highly resistant against shoot borer and the gene expression level is sufficient to provide complete resistance against target pests. Glyphosate spray assay was carried out for complete removal of weeds. In V1-generation, 70-76% transgenic sugarcane plants were found tolerant against glyphosate spray (3000mL/ha) under field conditions. While in V2-generation, the replicates of five selected lines 4L/2, 5L/5, 6L/5, L8/4, and L9/6 were found 100% tolerant against 3000mL/ha glyphosate spray. It is evident from current study that CEMB-GTGene, CEMB-Cry1Ac and CEMB-Cry2A genes expression in sugarcane variety CPF-246 showed an efficient resistance against cane borers (Chilo infuscatellus) and was also highly tolerant against glyphosate spray. The selected transgenic sugarcane lines showed sustainable resistance against cane borer and glyphosate spray can be further exploited at farmer’s field level after fulfilling the biosafety requirements to boost the sugarcane production in the country.
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Co-fermentation process is a potential tool to improve benefits of fruit and lactic acid bacteria to human health, beyond their technological functions. This study was conducted to compare the properties of dromedary bio-yogurt obtained by co-fermentation process with plant (carob powder) or autochthonous bacteria (Enterococcus faecium and Streptococcus macedonicus). For this reason, the total solids required for yogurt preparation were obtained by ultrafiltration (UF). Carob powder or autochthonous bacteria were incorporated at the level of 2% in UF milk. Then mixtures were fermented using conventional microorganisms for yogurt and obtained products named respectively CFC (yogurt with carob) and CFS CFS (yogurt with autochthonous strains). During the storage period, CFC and CFS maintained Streptococcus at appropriate levels (˃ 8 log CFU/g). Moreover, CFC showed the lowest syneresis, highest textural properties and oleic acid (C18:1n9; 26.315%). However, CFS yogurt resulted in higher aroma compounds formation than CFC and control (without co-fermentation). The principal component analysis (PCA) applied to the aroma compounds allowed the CFC to be differentiated to CFS and control on the one hand, and the CFC correlated with 4 volatile compounds where iso-bornyl propionate was the major, on the other hand. Although both control and CFS exhibited DPPH• inhibition, because of protein proteolysis during fermentation, significant increased radical scavenging activity was found in CFC samples. Meanwhile, the yogurt co-fermentation with carob powder displayed enhanced both the antioxidant and textural properties, which indicated that it has the potential value to be utilized as a novel functional food.
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Osthol [7-methoxy-8-(3-methylbut-2-en-1-yl) chromen-2-one] isolated from Prangos pabularia was used as a starting material for the synthesis of its various derivatives via modifications of the lactone ring. The resulting compounds were fully characterized by spectral techniques and evaluated for their anticancer activity against Hep-G2 (human hepatoma), HeLa (cervical carcinoma), U-87 (brain cancer) and MCF-7 (breast cancer) cell lines using MTT assay. All synthesized derivatives exhibited higher activity than that of osthol. Among this series, 4-bromophenyl, 3-hydroxyphenyl, and p-tolyl derivatives showed excellent cytotoxic activity against U-87 and MCF-7 cancer cell lines with IC50 values of 6–7.3 μM.
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Neurodegenerative disorders are termed as diversified group of disorders which comes under characterization of progressive degeneration in functioning of nervous system. Alzheimer and Parkinson’s disease comes under neurodegenerative disorder. Recent studies have identified that it is caused due to the mechanisms of cellular and molecular functions based on the aggregation of protein. The disease is basically diagnosed pathologically. Autopsy has become essential for diagnosing the disorder. Advanced research on this particular field has led to perspective that pathological changes can be made in the brain without an autopsy. The changes are reflected through molecular brain imaging techniques. The study focuses on various functional and cognitive assessment that has been followed until recent times in the field of medical image processing. Recent methodologies in diagnosing through molecular image techniques without an autopsy is a successive progress in the field of medical research. The challenges in functional and cognitive assessment perspective of the disorder is also focused. The complications include difficulties in memory. This survey provides an insight for future research direction in medical image processing.
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The antimicrobial peptides Ocellatin-LB1, -LB2 and -F1, isolated from frogs, are identical from residue 1 to 22, which correspond to the -LB1 sequence, whereas -LB2 carries an extra N and -F1 additional NKL residues at their C-termini. Despite the similar sequences, previous investigations showed different spectra of activities and biophysical investigations indicated a direct correlation between both membrane-disruptive properties and activities, i.e., ocellatin-F1 > ocellatin-LB1 > ocellatin-LB2. This study presents experimental evidence as well as results from theoretical studies that contribute to a deeper understanding on how these peptides exert their antimicrobial activities and how small differences in the amino acid composition and their secondary structure can be correlated to these activity gaps. Solid-state NMR experiments allied to the simulation of anisotropic NMR parameters allowed the determination of the membrane topologies of these ocellatins. Interestingly, the extra Asn residue at the Ocellatin-LB2 C-terminus results in increased topological flexibility, which is mainly related to wobbling of the helix main axis as noticed by molecular dynamics simulations. Binding kinetics and thermodynamics of the interactions have also been assessed by Surface Plasmon Resonance and Isothermal Titration Calorimetry. Therefore, these investigations allowed to understand in atomic detail the relationships between peptide structure and membrane topology, which are in tune within the series -F1>> -LB1 ≥ -LB2, as well as how peptide dynamics can affect membrane topology, insertion, and binding.
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