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21.
S. P. Gupte P. B. Jadkar R. V. Chaudhari 《Reaction Kinetics and Catalysis Letters》1984,24(1-2):173-177
Activity of Cu catalysts and kinetics of ethynylation of formaldehyde using Cu2C2 catalyst has been studied. The reaction was found to be 0.41 and 0.58 order with respect to acetylene and formaldehyde concentrations, respectively. The activation energy of the reaction was found to be 15.13 kcal/mol.
NCL Communication No.: 3095 相似文献
Cu2C2 . 0,41 0,58 . 15,13 /.
NCL Communication No.: 3095 相似文献
22.
Single‐step oxidative homocoupling of aryl Grignard reagents via Co(II), Ni(II) and Cu(II) Complexes under air
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A simple catalytic system of direct synthesis for the symmetrical biaryls using catalytic amounts of Co(II), Ni(II) and Cu(II) complexes has been developed. The reaction system involves in situ synthesis of Grignard reagents. The complexes, containing bidentate Schiff base and dmit (2‐thioxo‐1,3‐dithiole‐4,5‐dithiolate) ligands, were compatible with diverse functionalities and afford a high yield of biaryls in a single step, proving to be promising catalysts in homocoupling reactions. Atmospheric oxygen is used as an oxidant which renders a green, simple and economical catalytic route. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
23.
Anutosh Paria S. S. Greeshma Aparna Chaudhari M. Makesh C. S. Purushothaman K. V. Rajendran 《Applied biochemistry and biotechnology》2013,169(1):281-289
RNA interference-mediated silencing is an effective way of controlling white spot syndrome virus (WSSV). However, the effect of RNAi on the innate immune mechanism is not well understood. Prophenoloxidase (proPO) is an important component of the shrimp innate immunity. In the present study, nonspecific effect of two double-stranded (ds)RNA-expressing constructs, one targeting vp28 gene of WSSV (pCMV-VP28-LH) and another targeting green fluorescent protein (GFP) (pCMV-GFP-LH) on proPO2 gene expression, is investigated. mRNA expression levels of proPO2 in hemocytes of DNA construct-injected shrimp were estimated using real-time PCR with elongation factor 1-α as internal control. Empty vector (pcDNA)-injected shrimp were used as experimental control. In pCMV-VP28-LH-injected shrimp, proPO2 showed significant upregulation until 48 h post-injection (p.i.). Similarly, pCMV-GFP-LH-injected animals showed high levels of expression until 72 h p.i. WSSV-challenged animals, compared to pcDNA-injected control group, showed no significant change in expression of the gene until 24 h. However, an increased expression was noticed at 48 h p.i. Our results suggest that neither the plasmids nor the long hairpin RNA expressed by the constructs has any nonspecific silencing effect on the proPO2 expression. On the contrary, the consistent upregulation of proPO2 observed in shrimp injected with dsRNA at early time-points indicates the possibility of nonspecific protection against WSSV infection. 相似文献
24.
Structural Chemistry - This work reports hydrogen uptake capacity and equilibrium isotope effect (EIE) for the Be, Li, and Ti-doped closoborate (B6H6) complexes using first-principles calculations... 相似文献
25.
Aparna DeshpandeBrian J. LeRoy 《Physica E: Low-dimensional Systems and Nanostructures》2012,44(4):743-759
A material with novel fundamental properties that challenge our current understanding is always exciting for research. If the novel properties extend to the realm of device engineering and promise a revolution in applications, then the scope of its research knows no bounds. The story of graphene, the two dimensional form of carbon, has followed this path. Graphene has been the subject of numerous experimental and theoretical investigations since 2004 when an elegant and a simple technique to make monolayer graphene set the stage for extensive research. Many other techniques to make graphene were developed in parallel to this technique. As graphene is replete with unique structural and electronic properties scanning probe microscopy has proved to be an exciting and a rewarding venture. In this review we discuss the findings of scanning probe microscopy and how it has served as an indispensable tool to understand the properties of graphene and further graphene research. 相似文献
26.
Premchand B. Shelke Suraj N. Mali Hemchandra K. Chaudhari Amit P. Pratap 《Journal of heterocyclic chemistry》2019,56(11):3048-3054
Chitosan hydrochloride as biopolymer‐based, renewable, and recyclable heterogeneous catalyst was used for efficient one‐pot synthesis of perimidine derivatives. This newly developed greener methodology provides a very simple and greener route for the synthesis of perimidines in short time with excellent yield. 相似文献
27.
C. V. Chaudhari K. A. Dubey Y. K. Bhardwaj S. Sabharwal 《Journal of Macromolecular Science: Physics》2013,52(5):839-859
Different compositions of SBR/EPDM 50:50 blends containing multiple-walled carbon nanotubes (MWNT) as nanoparticulate fillers (0.5%–10%) were evaluated for radiation sensitivity and solvent permeability. The efficiency of radiation ***cross-linking was analyzed by gel-content and Charlesby–Pinner parameter measurements. ***Gamma-radiation-induced cross-linking extent was found to increase with radiation dose and MWNT concentration, which was reflected in different extents of swelling. Rigorous analysis of swelling and diffusion data, on the basis of the transport exponent (n) values and diffusion/relaxation rate indicated anomalous diffusion behavior for most of the nanocomposites. The swelling extent in different solvents was found to be a function of polymer-solvent interaction as well as stearic hindrance due to the structure/size of the solvent molecules. Polymer-filler interaction investigated by a Kraus plot indicated high reinforcement of the SBR/EPDM matrix on MWNT addition. There was no significant change in surface energy or hydrophilicity of the SBR/EPDM matrix on introduction of MWNT into it. 相似文献
28.
Kumar Umesh Santu Kaity Banerjee Aparna Arya A. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3505-3516
Journal of Radioanalytical and Nuclear Chemistry - Literature studies reveal apaucity of data on the Th-Zr system. Investigations on the Th-30Zr alloy and its synthesis, microstructure and... 相似文献
29.
Saurabh B. Ganorkar Suraj R. Chaudhari Preeti S. Bobade Sagar H. Pawar Atul A. Shirkhedkar 《Biomedical chromatography : BMC》2022,36(5):e5345
Rufinamide is used presently to treat Lenaux–Gastaut syndrome. A full factorial design and desirability approach was investigated for the optimization of hydrolytic stress via response surface curves (RSCs). The degradation impurities were identified and resolved using reversed-phase high-performance liquid chromatography (RP-HPLC) on the Qualisil® BDS C8 column. Acetonitrile–water (29:71, v/v) was optimized for the mobile phase and used at a flow rate of 1.0 ml/min with detection at a wavelength of 230 nm. Rufinamide showed appreciable susceptibility to hydrolysis under acidic and alkaline stress, and substantial degradation in the neutral condition. It degraded much less under oxidative stress. Exposure towards thermal and photolytic stress conditions indicated appreciable stability. The developed method was subjected to validation as per the recommendations of the International Conference on Harmonization. The proposed method showed no influence from the excipients and the degradation products. As well as good precision and accuracy in determination, the method showed a linear response between 2 and 12 μg ml−1. The method was extended for determination in a human plasma sample, which resulted in excellent recovery without interference from matrix effects. The combined use of desirability and design for the optimization of acidic and alkaline hydrolytic stress led to simple and rapid analysis. 相似文献
30.
Anand Kumar Chaudhari Vipin Kumar Singh Abhishek Kumar Dwivedy Somenath Das Neha Upadhyay Akanksha Singh 《Natural product research》2020,34(5):745-749
AbstractThe chemical characterisation of Pimenta dioica essential oil (PDEO) revealed the presence of 50 components, amongst which α-Terpineol (30.31%) was the major component followed by β-Linalool (6.75%) and γ-Terpinene (4.64%). The oil completely inhibited the growth of aflatoxin B1 secreting strain Aspergillus flavus LHP-VS-8 and aflatoxin B1 production at 2.5?µL/mL and 1.5?µL/mL, respectively. The oil caused dose dependent reduction of methylglyoxal (an AFB1 inducer), enhanced leakage of Ca2+, Mg2+ and K+ ions and significantly reduced ergosterol content of fungal plasma membrane. During in situ experiments, PDEO exhibited complete protection of fumigated maize cob slices from fungal infestation without affecting seed germination. The chemically characterised PDEO is recommended as a plant based preservative and shelf life enhancer of food commodities by preventing fungal growth, AFB1 production and lipid peroxidation. This is the first report on PDEO as inhibitor of AFB1 secretion and methylglyoxal biosynthesis. 相似文献