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排序方式: 共有133条查询结果,搜索用时 31 毫秒
71.
Rao RS Rasheed MA Kalpana G Patil DJ Kumar B 《Applied biochemistry and biotechnology》2005,126(3):205-214
Pichia angusta MTCC-225, a catalase-positive yeast that utilizes methanol and lighter hydrocarbons, is the subject of this investigation.
An orthogonal experimental design L16 was used to investigate the effects of methanol, a gas mixture, zero air, temperature, agitation, and salts solution on hydrocarbon
utilizing P. angusta. QUALITEK-4 Software was used for automatic design and analysis of the experimental results. Among the various parameters
tested, agitation contributed the highest influence (56.5%). Zero air, methanol concentration, and gas mixture showed a moderate
influence on the growth of P. angusta. Methanol concentration and gas mixture showed a 10.91 and 10.12% influence, respectively, on yeast growth. Zero air played
an important role, with a 15.19% influence on the utilization of hydrocarbon. 相似文献
72.
Rumalla Chidananda Swamy Avula Bharathi Wang Yan-Hong Smillie Troy J. Khan Ikhlas A. 《平面色谱法杂志一现代薄层色谱法》2012,25(5):409-414
JPC – Journal of Planar Chromatography – Modern TLC - A high-performance thin-layer chromatographic (HPTLC) method was developed for the quantification of two anthocyanins, viz.,... 相似文献
73.
Harish Kumar Yadav K. Sreenivas R. S. Katiyar Vinay Gupta 《Journal of Raman spectroscopy : JRS》2011,42(8):1620-1625
Decay dynamics of the acoustic phonon mode in ZnO nanoparticles, synthesized using the wet chemical technique, is investigated. It is well established that optic phonon modes in a semiconductor favor an anharmonic decay dynamics; in contrast, acoustic modes evidence a rather complex decay behavior, manifesting their dependence on other parameters such as particle size, impurity species, etc. At lower temperatures (T < 500 K), the anharmonic decay process, caused by the weakening of the bond strength, is responsible for the observed decrease in the acoustic mode wavenumbers. However, particle growth due to the coalescence sintering process is prominent at higher temperatures (>600 K) and governs the softening behavior of the acoustic phonon mode towards the Rayleigh line. On the other hand, the precursor species and reaction byproducts on the surface of ZnO nanoparticles induce an anomalous softening behavior in the decay dynamics at specific temperatures by damping the acoustic phonon mode. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
74.
Bharathi Avula Yan-Hong Wang Troy J. Smillie Wilfred Mabusela Leszek Vincent Frans Weitz Ikhlas A. Khan 《Chromatographia》2009,70(5-6):797-803
Simple and specific analytical methods for the quantitative determination of sesquiterpenoids from various species of Artemisia plant samples were developed. By LC–UV, LC–ELSD, the separation was achieved by reversed-phase chromatography on a C18 column with water and acetonitrile both containing 0.025% trifluoroacetic acid as the mobile phase. In the LC–MS system, trifluoroacetic acid was replaced by 0.1% formic acid. The wavelength used for quantification of sesquiterpenoids with a diode array detector was 205 nm. The limits of detection by LC–MS was found to be 5, 10, 25, 50, 50 ng mL?1. The limits of detection by LC–UV and LC–ELSD were found to be 5.0, 3.0, 100, 100, 7.5 μg mL?1, by LC–UV and 50, 25, 30, 100 and 75 μg mL?1 by LC–ELSD. LC–mass spectrometry coupled with electrospray ionization (ESI) interface is described for the identification and quantification of sesquiterpenoids in various plant samples. This method involved the use of the [M + H]+ ions of sesquiterpenoids in the positive ion mode with extractive ion monitoring. 相似文献
75.
The novel carboxamide-pyridine N-oxide synthon, sustained via N-H...O- hydrogen bonding and C-H...O interaction, is shown to assemble isonicotinamide N-oxide in a triple helix architecture and the same heterosynthon is exploited to synthesize cocrystals of barbiturate drugs with 4,4'-bipyridine N,N'-dioxide. 相似文献
76.
David D. Díaz Sreenivas Punna Philipp Holzer Andrew K. McPherson K. Barry Sharpless Valery V. Fokin M. G. Finn 《Journal of polymer science. Part A, Polymer chemistry》2004,42(17):4392-4403
The copper(I)‐catalyzed cycloaddition reaction between azides and alkynes has been employed to make metal‐adhesive materials. Copper and brass surfaces supply the necessary catalytic Cu ions, and thus the polymerization process occurs selectively on these metals in the absence of added catalysts. Alternatively, copper compounds can be added to monomer mixtures and then introduced to reducing metal surfaces such as zinc to initiate polymerization. The resulting materials were found to possess comparable or superior adhesive strength to standard commercial glues, and structure‐activity correlations have identified several important properties of the monomers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4392–4403, 2004 相似文献
77.
Treatment of indoles with ammonium thiocyanate in the presence of para-toluene sulfonic acid afforded the corresponding 3-thiocyano indoles at room temperature in excellent yields. 相似文献
78.
1-Alkynes undergo smooth addition to activated quinolines, isoquinolines and pyridines in the presence of copper iodide/iPr2NEt under extremely mild conditions to afford 2-alkynyl-1,2-dihydroquinolines in excellent yields with high selectivity. This method is also useful for functionalization of monocyclic pyridines. 相似文献
79.
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