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51.
A stationary sequence of random variables with Birnbaum‐Saunders marginal distribution is constructed using a Gaussian autoregressive moving average sequence. The parameters of the model are then estimated by the maximum likelihood method, and the resulting estimators are shown to be consistent and asymptotically normal. A simulation study is carried out to assess the performance of the estimators. The proposed model is finally used to analyze 2 real data sets. 相似文献
52.
S. Swetha S. M. Santhosh R. Geetha Balakrishna 《Photochemistry and photobiology》2010,86(5):1127-1134
Photocatalyst-mediated inactivations generate reactive oxygen species and OH radicals, which induce oxidative destruction of membrane integrity, causing damage to membrane phospholipids of gram negative bacteria like Pseudomonas aeruginosa. Nanosized TiO2 was synthesized by gel to crystalline conversion and Zr-doped TiO2 was synthesized by pulverization using appropriate precursor. The doped nanocrystals retained the anatase phase with a marginal increase in crystallite size, averaging at 25 nm. SEM–EDX analysis of the doped sample depicts the substantial growth of grain size with 1.33 atomic weight % of zirconium. The created electron states in the doped sample act as charge carrier traps suppressing recombination which later detraps the same to the surface of the catalyst causing enhanced interfacial charge transfer. Zr-doped TiO2 at the molecular scale exhibits better photocatalytic activity with lower bandgap energy that can respond to visible light. The redshift caused by the dopants in absorption spectra of TiO2 facilitated the nonintrinsic sample to exhibit nearly 2-fold enhancement of photoinactivation in sunlight. Extent of photoinactivation of P. aeruginosa was observed to be complete (100%) within 150 min of sunlight exposure in the presence of modified TiO2. 相似文献
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Mari Sithambaram Karthikeyan Bantwal Shivarama Holla Balakrishna Kalluraya Nalilu Suchetha Kumari 《Monatshefte für Chemie / Chemical Monthly》2007,138(12):1309-1316
Summary. A series of dichlorofluorophenyl containing triazolothiadiazoles were obtained by cyclocondensation of triazole with substituted
benzoic, aryloxyacetic, and anilinoacetic acids using POCl3 as cyclizing agent. The structures of the newly synthesized compounds were characterized and confirmed by IR, 1H NMR, mass spectra, and elemental analysis. Selected compounds were screened for their antitubercular activity against Mycobacterium tuberculosis. The compound bearing 2,4-dichloro-5-fluorophenyl moiety at position 3, and 6 of the triazolothiadiazole showed excellent
activity in vitro primary screening. Compounds with 3-chloro-4-fluorophenyl and 4-fluorophenoxymethyl moieties at position 6 of the triazolothiadiazole
showed very good analgesic activity. Triazolothiadiazole with 4-chlorophenyl, 4-fluoro-3-phenoxyphenyl, and 2,4-dichloro-5-fluorophenyl
moieties showed excellent antimicrobial activity against the tested strains at 6.25 μg cm−3 concentrations. 相似文献
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Light petroleum extract of the heartwood of Dalbergia latifolia, yields a colourless crystalline solid, latifolin, which is a dihydroxy, dimethyl compound having a C15 skeleton similar to dalbergin. The constitution of the dimethyl ether is shown to be γ,γ-(2,2′,4,5-tetramethoxy)-diphenyl propene (II). 相似文献
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Balakrishna Kolli Someshwarnath Pandey Sarada P. Mishra Tapan Kanai Mukesh P. Joshi Raj S. Mohan Tham Singh Dhami Lalit Mohan Kukreja Asit Baran Samui 《Journal of polymer science. Part A, Polymer chemistry》2013,51(20):4317-4324
Main chain polymers containing azo and bisbenzylidene moiety were synthesized by polycondensation method. The successful polymerization reaction was characterized by UV–vis absorption, FT‐IR and NMR spectroscopy. The resulting polymers were soluble in polar solvents like dimethyl formamide (DMF) and showed good thermal stability up to 250 °C. These polymers were blended with poly methyl methacrylate (PMMA) and corona poled for characterizing second harmonic generation (SHG) property. Temperature stability study of SHG intensity of poled polymer showed that it is stable up to 80 °C. To improve temperature stability further the crosslinking of polymer under UV light is proposed. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4317–4324 相似文献