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561.
CoS@MorphcdtH NPs and CoS@4-MPipzcdtH NPs were synthesized by precipitation method involving three mechanisms: inclusion, occlusion, and adsorption. The synthesized NPs were characterized with the help of UV-Vis spectroscopy, FESEM-EDAX, powder x-ray diffraction, TEM, ESIMS, TG/DSC analysis. The morphology of the CoS@MorphcdtH NPs and CoS@4-MPipzcdtH NPs were hexagonal and rectangular, and the particles were in the range 7–12 nm. UV–visible spectral measurements showed surface plasmon resonance at 320 nm–340 nm with band gap of 3.65 eV–3.86 eV. The catalytically active CoSNPs called were investigated for the reduction of 4-nitrophenol (4-NP) via hydrogenation using sodium borohydride (NaBH4) as a reducing agent. Both the CoS NPs successfully reduced 4-NP to 4- aminophenol (4-AP) in a short time, catalytic performances are almost unchanged for the first five cycles. Herein, we report the preparation and characterizations of efficient active CoS NPs consisting carbodithioic acid framework as a support/capping material, along with catalytic property.  相似文献   
562.
In the current scenario, people are highly concerned regarding their health and constantly desire a healthy and nutritious diet. Moringa oleifera is traditionally known as saijhan or drumstick tree. The plant is native to tropical Asia and thus found in various parts of the country India. Being a nutrient-rich plant, Moringa leaves play a vital role in the treatment of malnutrition. It also has anti-inflammatory, anti-spasmodic, anti-asthmatic, anti-ulcer, hypocholesterolemic, and hypoglycemic properties. Fresh fruits have also been desirable and in growing demand, because of healthy food consumption trends worldwide. The following study was undertaken to provide nutrient-rich food in the busy growing lifestyle. Thus, in this study, preparation and optimization of the Moringa leaf powder have been done. The final product is developed by incorporating Moringa leaf powder into pomegranate juice to prepare a ready-to-serve (RTS) beverage. On the basis of this study, it concluded that 100:2:2.8:0.2 concentration of Pomegranate, Moringa oleifera leaf powder, Sugar, Citric Acid is suitable for the preparation of Ready to Serve Beverage. In this study, proximate analysis and sensory evaluation have been performed to understand the overall acceptability of the final product.  相似文献   
563.
Molecular Diversity - Recently, researchers have shown great interest in compounds such as triflate and enotriflate that are synthesized by Comins reagent. For the above-mentioned reason, we...  相似文献   
564.
This paper examines the linear hydrodynamic stability of an inviscid compound jet. We perform the temporal and the spatial analyses in a unified framework in terms of transforms. The two analyses agree in the limit of large jet velocity. The dispersion equation is explicit in the growth rate, affording an analytical solution. In the temporal analysis, there are two growing modes, stretching and squeezing. Thin film asymptotic expressions provide insight into the instability mechanism. The spatial analysis shows that the compound jet is absolutely unstable for small jet velocities and admits a convectively growing instability for larger velocities. We study the effect of the system parameters on the temporal growth rate and that of the jet velocity on the spatial growth rate. Predictions of both the temporal and the spatial theories compare well with experiment.Dedicated to the memory of Professor Tasos C. Papanastasiou  相似文献   
565.
Electrophilic substitution of acylmethanes (methyl ketones), RCOCH3 (R = i-Pr, 1; Et, 2; Me, 3) with aryltellurium trichlorides, ArTeCl3 (Ar = 1-C10H7, Np, A; 2,4,6-Me3C6H2, Mes, B; 4-MeOC6H4, Anisyl, C) under mild conditions affords the corresponding acylmethyl(aryl)tellurium dichlorides (RCOCH2)ArTeCl2. Reduction of the dichlorides, gives tellurides, (i-PrCOCH2)ArTe, 1A-1C, which give the corresponding dihalides, (i-PrCOCH2)ArTeX2 (X = Cl, 1Aa-1Ca; Br, 1Ab-1Cb; I, 1Ac-1Cc) when reacted in situ with SO2Cl2, Br2 or I2. The unsymmetric tellurides are labile towards disproportionation and attempts to obtain them lead to the isolation of Ar2Te2 except in the case of (i-PrCOCH2)MesTe (1B), which represents an interesting example of a kinetically stable aryl(alkyl)telluride. All the dihalomesityltellurium(IV) derivatives show separate 1H and 13C NMR signals for the ortho methyls irrespective of the sizes of R and X ligands. The telluride, 1B with free rotation about Te-C(mesityl) bond shows, like the unsymmetric diorganotellurium(IV) dihalides, only one 125Te NMR signal. The 1,4-chelating behavior of the acyl ligand among diorganotellurium(IV) compounds is inferred from the X-ray diffraction data for 1Aa, 1Ac, 1Ba, 1Bb, 1cA and 1Cc which are indicative of the presence of intramolecular Te...O secondary bonding interactions (SBIs) at least in the solid state. As a consequence, steric repulsion in case of the mesityltellurium(IV) derivatives, 1Ba and 1Bb, reaches the threshold so as to cause loss of two-fold rotational symmetry of the mesityl group about the Te-C(mesityl) bond axis. Intermolecular C-HO...O H-bonding interactions appears to stabilize such an orientation of the aryl ligand at least in the solid state.  相似文献   
566.
A novel strategy for the synthesis of 6-methyl benzofuro[3,2-c] quinoline derivatives via copper-catalyzed dehydrogenative C O arylation has been presented. Optimization studies have been carried out by varying various catalysts, bases, solvents, and other physical parameters. Keeping use of this dehydrogenative cross-coupling C O arylation reaction, a variety of bioactive building blocks like fused benzofuro quinoline heterocycles were smoothly assembled in moderate to higher yields.  相似文献   
567.
In recent years, considerable importance is given to the use of agrifood wastes as they contain several groups of substances that are useful for development of functional foods. As muscle foods are prone to lipid and protein oxidation and perishable in nature, the industry is in constant search of synthetic free additives that help in retarding the oxidation process, leading to the development of healthier and shelf stable products. The by-products or residues of pomegranate fruit (seeds, pomace, and peel) are reported to contain bioactive compounds, including phenolic and polyphenolic compounds, dietary fibre, complex polysaccharides, minerals, vitamins, etc. Such compounds extracted from the by-products of pomegranate can be used as functional ingredients or food additives to harness the antioxidant, antimicrobial potential, or as substitutes for fat, and protein in various muscle food products. Besides, these natural additives are reported to improve the quality, safety, and extend the shelf life of different types of food products, including meat and fish. Although studies on application of pomegranate by-products on various foods are available, their effect on the physicochemical, oxidative changes, microbial, colour stabilizing, sensory acceptability, and shelf life of muscle foods are not comprehensively discussed previously. In this review, we vividly discuss these issues, and highlight the benefits of pomegranate by-products and their phenolic composition on human health.  相似文献   
568.
Nanofluid is an innovative heat transfer fluid with superior potential for enhancing the heat transfer performance of conventional fluids. Though many attempts have been made to investigate the abnormal high thermal conductivity of nanofluids, the existing models cannot precisely predict the same. An attempt has been made to develop a model for predicting the thermal conductivity of different types of nanofluids. The model presented here is derived based on the fact that thermal conductivity of nanofluids depends on thermal conductivity of particle and fluid as well as micro-convective heat transfer due to Brownian motion of nanoparticles. Novelty of the article lies in giving a unique equation which predicts thermal conductivity of nanofluids for different concentrations and particle sizes which also correctly predicts the trends observed in experimental data over a wide range of particle sizes, temperatures, and particle concentrations.  相似文献   
569.
570.
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