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11.
Growth and characterization of semiorganic NLO crystal of l-glutamic acid hydrochlorobromide (LGHCB)
Single crystals of nonlinear optical material l-glutamic acid hydrochlorobromide (LGHCB) were grown by slow evaporation technique from its aqueous solution. Optically good quality crystals of dimension 20 × 10 × 2 mm3 were obtained. The lattice parameters for the grown crystals were determined using single crystal X-ray diffraction study. The LGHCB crystal belongs to non-centrosymmetric P212121 space group. The crystal structure was resolved by direct method and refined by full matrix least-square method using SHELXL-97. Using the powder X-ray diffraction study, the crystallinity of the grown crystal was confirmed and the diffraction peaks are indexed. From Fourier transform infrared spectroscopy study, the various functional groups present in LGHCB crystal were elucidated. The UV–Vis-NIR absorption spectrum was recorded in the range of 200–2,000 nm, and the lower cut off wavelength is ~235 nm. Optical band gap of the grown crystal was found to be 5.22 eV. Thermal properties of LGHCB crystal were studied by thermogravimetric analysis and derivative thermogravimetric analysis. The second harmonic generation efficiency of LGHCB crystal was confirmed by Kurtz’s powder technique. 相似文献
12.
K.Kesavan Chithra M.Mathew S.Rajendran 《中国化学快报》2014,25(11):1428-1434
Poly(ethylene oxide), poly(vinyl pyrrolidone)(PEO/PVP), lithium perchlorate salt(Li Cl O4) and different plasticizer based, gel polymer electrolytes were prepared by the solvent casting technique. XRD results show that the crystallinity decreases with the addition of different plasticizers. Consequently, there is an enhancement in the amorphousity of the samples responsible for the process of ion transport. FTIR spectroscopy is used to characterize the structure of the polymer and confirms the complexation of plasticizer with host polymer matrix. The ionic conductivity has been calculated using the bulk impedance obtained through impedance spectroscopy. Among the various plasticizers, the ethylene carbonate(EC) based complex exhibits a maximum ionic conductivity value of the order of2.7279 10 4S cm 1. Thermal stability of the prepared electrolyte films shows that they can be used in batteries at elevated temperatures. PEO(72%)/PVP(8%)/Li Cl O4(8%)/EC(12%) has the maximum ionic conductivity value which is supported by the lowest optical band gap and lowest intensity in photoluminescence spectroscopy near 400–450 nm. Two and three dimensional topographic images of the sample having a maximum ionic conductivity show the presence of micropores. 相似文献
13.
Sridevi Duggirala Rakesh P. Nankar Selvakumar Rajendran Mukesh Doble 《Applied biochemistry and biotechnology》2014,174(1):283-296
Naturally occurring phytochemicals with reported antibacterial activity were screened for their ability to inhibit the bacterial cell division protein Escherichia coli FtsZ. Among the representative compounds, coumarins inhibit the GTPase and polymerization activities of this protein effectively. Further screening with ten coumarin analogs we identified two promising candidates, scopoletin and daphnetin. The former is found to inhibit the GTPase activity of the protein in a noncompetitive manner. Docking of these coumarins with the modeled protein indicate that they bind to T7 loop, which is different from the GTP-binding site (active site), thereby supporting the experimental data. Lowest binding energy is obtained with scopoletin. 3D QSAR indicates the need for groups such as hydroxyl, diethyl, or dimethyl amino in the 7th carbon for enhanced activity. None of the coumarins exhibited cytotoxicity against NIH/3T3 and human embryonic kidney cell lines. The length of Bacillus subtilis increases in the presence of these compounds probably due to the lack of septum formation. Results of this study indicate the role of coumarins in halting the first step of bacterial cell division process. 相似文献
14.
Neha Batra Vinoth Rajendran Ishan Wadi Ankit Lathwal Roshan Kumar Dutta Prahlad C. Ghosh Rinkoo D. Gupta Mahendra Nath 《Journal of heterocyclic chemistry》2020,57(4):1625-1636
A series of benzenesulfonamide-appended [1,2,3]-triazole hybrids was synthesized by using [3 + 2] cycloaddition of primary, secondary, and tertiary sulfonamide azides with various phenoxymethylacetylenes under click reaction conditions. After structural characterization, the compounds were subjected to in-silico absorption, distribution, metabolism, excretion and toxicity (ADMET) screening to evaluate their drug-likeness and other pharmacokinetic parameters. Furthermore, their in vitro antiplasmodial potential was assessed against Plasmodium falciparum (3D7) strain, and some of the synthesized compounds displayed promising antimalarial potency. On cytotoxicity evaluation using MTT cell viability assay, the most active candidate N-(4,6-dimethylpyridin-2-yl)-4-(4-(4-nitrophenoxy)methyl)-1H-[1,2,3]-triazol-1-yl)benzenesulfonamide ( 14 ; IC50 6.2 μg/mL) demonstrated CC50 7.5 μg/mL against human hepatocarcinoma (HUH-7) cells. 相似文献
15.
Rajendran Duraisamy Ramalingam Ganapathy Sundaram Esakkimuthu Jawahar Paulraj Sivakumar Vaithilingam Mahian Omid Bellos Evangelos 《Journal of Thermal Analysis and Calorimetry》2020,140(1):33-51
Journal of Thermal Analysis and Calorimetry - The solar collector (reflector and receiver) is the primary device being used in the concentrating solar power technologies for tapping the solar... 相似文献
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Investigations on PMMA-PVdF polymer blend electrolyte with esters of dibenzoic acids as plasticizers 总被引:1,自引:0,他引:1
Plasticizers can be used to change the electrical and mechanical properties of polymer electrolytes by reducing the degree
of crystallinity and lowering the glass transition temperature. The transport properties of gel type ionic conducting membranes
consisting of poly (methyl methacrylate) (PMMA), poly (vinylidene fluriode) (PVdF), Lithium perchlorate (LiClO4) and dioctyl phthalate (DOP), dibutyl phthalate (DBP), dimethyl phthalate (DMP) or diethyl phthalate (DEP) were studied.
The polymer films were characterized by X-ray diffraction, Thermal, Fourier transform infrared and impedance spectroscopic
studies. It is found that the addition of DMP as the plasticizer in the PMMA / PVdF-LiClO4 polymer complex favours an enhancement in ionic conductivity. The temperature dependence of the conductivity of the polymer
films seems to obey the VTF relation. The conductivity values are presented and the results are discussed. 相似文献
20.
Methyl‐3‐(2‐chloroquinolin‐3‐yl)acrylates 5a‐i on reaction with methyl amine in acetonitrile yielded methyl‐3‐[2‐(methylamino)quinolin‐3‐yl]acrylates 6a‐i . When, these were followed by the reaction with the Vilsmeier reagent, they afforded methyl benzo[b][1,8]naphthyridin‐3‐carboxylate 7a‐i in good yields. 相似文献