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51.
Kiranmayee Rao Bhuvaneswari Ch Lakshmi M. Narasu Archana Giri 《Applied biochemistry and biotechnology》2010,162(3):871-884
Methanol, acetone and diethyl ether extracts of Alpinia galanga have been evaluated against pathogens viz. Bacillus subtilis MTCC 2391, Enterobacter aerogene, Enterobacter cloacae, Enterococcus faecalis, Escherichia coli MTCC 1563, Klebsiella pneumoniae, Pseudomonas aeruginosa MTCC 6642, Salmonella typhimurium, Staphylococcus aureus and Streptococcus epidermis using Agar well diffusion method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of
all the extracts were determined using the macrodilution method. Methanol extracts have shown excellent activity towards all
the pathogens with MIC and MBC values ranging from 0.04–1.28 mg/ml and 0.08–2.56 mg/ml, respectively. The GC–MS analysis of
methanol extracts have yielded compounds like 5-hydroxymethyl furfural (59.9%), benzyl alcohol (57.6%), 1,8 cineole (15.65%),
methylcinnamate (9.4%), 3-phenyl-2-butanone (8.5%) and 1,2 benzenedicarboxylic acid (8.9%), which could be responsible for
its broad spectrum activity. So, A. galanga can be quite resourceful for the development of new generation drugs. 相似文献
52.
Lakshmi Vijayan 《Physica B: Condensed Matter》2009,404(20):3539-3543
The ac electrical conductivity properties of LiTi2(PO4)3 (LTP) polycrystalline material in two different crystallite sizes are compared. Micrometer sized LTP is prepared by conventional solid-state reaction. LTP crystallites of 71 nm size are prepared by solid-state reaction of 40 h planetary milled stoichiometric mixture. The XRD and SEM are used as characterization techniques. Electrical properties are studied using impedance spectroscopic technique. Ball-milled LTP shows one order increase in grain-interior conduction compared to microcrystalline LTP at 388 K. The increase in conduction results from decreased crystallite size. 相似文献
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A new cyclic amide heterodimer has been isolated from Clausena-lansium leaves. The structure of this amide heterodimer was determined by X-ray crystallographic studies and spectrochemical evidence. 相似文献
57.
Clark RD Kar J Akella L Soltanshahi F 《Journal of chemical information and computer sciences》2003,43(3):829-836
Optimizable k-dissimilarity (OptiSim) selection entails drawing a series of subsamples of size k from a population and choosing the "best" candidate from each such subsample for inclusion in the selection set. By varying the size of the subsample, one can control the balance between representativeness and diversity in the selection set obtained. In the original formulation, a uniform random sampling from among valid candidates was used to draw the subsamples from a single target population. Here we describe in detail two key modifications that serve to extend the OptiSim methodology to vector selection for interdependent variables, specifically as applied to the design of combinatorial sublibraries. The first modification involves pivoting between variables: subsamples are drawn from each reagent pool in turn, with the viability of each candidate being evaluated in isolation as well as in terms of the products it will produce from complementary reagents already selected. The filters applied may be static or dynamic in nature, with molecular weight and hydrophobicity being examples of the former and structural diversity with respect to reagents already selected being an example of the latter. The second key modification is adding the ability to bias the selection of candidate reagents for inclusion in the subsamples. Taken together, these modifications support the efficient generation of multiblock and other sparse matrix designs that are both representative and diverse, and for which "backfilling" of designs edited to remove undesirable reagents or products is straightforward. The method is intrinsically fast and efficient, since enumeration of the full combinatorial is not required- only those candidates actually considered for inclusion need be evaluated. Moreover, because the subsample selection step is separate from the diversity-based selection of the "best" candidate, incorporating such bias in favor of a competing criterion such as low price provides a "natural," nonparametric mechanism for generating designs that are likely to be "good" in a double-objective, Pareto sense. 相似文献
58.
Raja Lakshmi P. Manivannan R. Jayasudha P. Elango Kuppanagounder P. 《Research on Chemical Intermediates》2018,44(4):2807-2821
Research on Chemical Intermediates - Three new benzoquinone–imidazole ensembles possessing varying number (0, 1 and 2) of electron-withdrawing bromo substituents on the quinone ring have been... 相似文献
59.
Lanthanum Trichloride is an effective catalyst for the protective tetrahydropyranylation of alcohols and phenols. The catalyst is recycled almost quantitatively. 相似文献
60.
Hina Bhargava N. Lakshmi Ram Kripal Sharma K. Venugopalan 《Hyperfine Interactions》2008,183(1-3):155-161
Low temperature Mössbauer and AC susceptibility have been used to study relaxation phenomena in nano-sized particles of Cr0.25Co0.25Zn0.5Fe2O4. From these studies, the energy density constant for this system has been estimated to be 4 x 106 erg/cm3. Cation distribution has also been determined and the observed results are correlated to calculated relaxation times. 相似文献