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91.
The steady-state movement of the spherical and non-spherical particles, such as prolate or oblate rotational ellipsoids, cylinders, or parallelepipeds, suspended in a liquid and exposed to a unidirectional temperature gradient, is analyzed theoretically. The differences in the ratios of the rotational to translational diffusion coefficients of the non-spherical to spherical particles, the heterogeneity of thermal conductivity of the particle body, and the heterogeneity in surface chemical nature make possible to separate the particles according to differences in shape. Preliminary experimental separations of Gram-positive and Gram-negative, nearly spherical and rod-shaped bacteria performed by Microthermal Field-Flow Fractionation confirmed that the fractionation of the cells according to differences in shape is possible. 相似文献
92.
初步探讨了毛细管整体柱的制备方法及其在气相色谱分析中的应用。以液相色谱用毛细管整体柱作为研究基础,通过改变甲苯和十二醇的比例,使整体柱适用于气相色谱分析。通过二乙烯苯与键合在管壁上的3-(异丁烯酰氯)丙基三甲氧基硅烷(TMP)键合以及其自身的聚合,获得具有牢固结构、良好机械强度的整体柱。将其用于混合溶剂的分析和白酒标样的分析,可直接分析水中低碳醇。与现有的商品柱进行比较,结果表明所制备的整体柱均优于用以对照的商品色谱柱,其中在混合溶剂的分析中,醇类、酯类、酮类和芳烃类的峰形均优于用于比较的多孔层开口管(PLOT)柱;在白酒标样分析中,使得乙醛、甲醇、乙酸乙酯的色谱峰能够分开,比现有的聚乙二醇(PEG-20M)柱的分析方法更为便捷。 相似文献
93.
94.
Recent developments in microbial inulinases 总被引:15,自引:0,他引:15
Ashok Pandey Carlos R. Soccol Ponniah Selvakumar Vanete T. Soccol Nadia Krieger Jose D. Fontana 《Applied biochemistry and biotechnology》1999,81(1):35-52
Microbial inulinases are an important class of industrial enzymes that have gained much attention recently. Inulinases can
be produced by a host of microorganisms, including fungi, yeast, and bacteria. Among them, however, Aspergillus sp. (filamentous fungus) and Kluyveromyces sp. (diploid yeast) are apparently the preferred choices for commercial applications. Among various substrates (carbon source)
employed for their production, inulin-containing plant materials offer advantages in comparison to pure substrates. Although
submerged fermentation has been universally used as the technique of fermentation, attempts are being made to develop solidstate
fermentation technology also. Inulinases catalyze the hydrolysis of inulin to d-fructose (fructose syrup), which has gained an important place in human diets today. In addition, inulinases are finding
other newer applications. This article reviews more recent developments, especially those made in the past decade, on microbial
inulinases—its production using various microorganisms and substrates. It also describes the characteristics of various forms
of inulinases produced as well as their applications. 相似文献
95.
Muhammad Zaheer Afzal Shah Zareen Akhter Rumana Qureshi Bushra Mirza Misbah Tauseef Michael Bolte 《应用有机金属化学》2011,25(1):61-69
Synthesis of ferrocenyl Schiff bases ( 1–6 ) was carried out by the condensation reaction of 4‐ferrocenyl aniline with different substituted aromatic aldehydes and acetyl acetone. Compounds were characterized by physical measurements, elemental analysis, FT‐IR, 1H‐NMR and 13C‐NMR spectroscopy. Single crystal X‐ray analysis of compound 2 showed the co‐planarity of both aromatic rings connected by a C–N double bond. Compounds demonstrated reversible one‐electron redox behavior and their peak currents were found to increase linearly with the square root of the sweep rate ν1/2. The overall electrode processes were found to be diffusion controlled. Compounds 1 and 4 showed low cytotoxicity and appreciable antifungal, antioxidant and DNA protection activities. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
96.
D. Zappe 《Isotopes in environmental and health studies》2013,49(7):272-274
Investigations made into a gas-solid-fluidized bed model reactor, aiming at obtaining statements about the spatial and time density distributions within the fluidized bed and the correlation between the state of the turbulent layer and a characteristic measured quantity as well as variation of a physical property of the solid. statisticl evaluation techniques are indispensable, owing to the elementary actions occuring within the fluidized bed reactor and their random nature. Such parameters of the fluidized bed could be determined from a totality of individual measurements for measuring periods of 10 ms per single measurement by use of a miniature measuring probe within the interior of the fluidized bed reactor. This probe consisted of a beta-radition source and a Si-surface barrier-layer detector. 相似文献
97.
János D. Pintér 《Journal of Global Optimization》2007,38(1):79-101
The Lipschitz Global Optimizer (LGO) software integrates global and local scope search methods, to handle a very general class
of nonlinear optimization models. Here we discuss the LGO implementation linked to the General Algebraic Modeling System (GAMS).
First we review the key features and basic usage of the GAMS /LGO solver option, then present reproducible numerical results
to illustrate its performance. 相似文献
98.
S. Lorenzo-Freire J.M. Alonso-Meijide B. Casas-Méndez M.G. Fiestras-Janeiro 《European Journal of Operational Research》2007
In this paper, we provide a new characterization of the Deegan–Packel power index, which uses a new monotonicity property, and two characterizations of the Johnston power index by employing some usual properties of the literature and two new transfer properties. Finally, a real-world numerical example taken from the political field illustrates the main differences between these two indices. 相似文献
99.
R. Wilfinger J. Lettry A. Fabich H. Aiginger K. Poljanc R. Catherall M. Eller 《The European physical journal. Special topics》2007,150(1):373-378
Thermal stress-waves are generated in the solid target
material when the proton beam interacts. These stress waves excite
natural oscillations of the target or cause plastic deformations.
Hence, an experimental setup with a laser Doppler vibrometer
[CITE] was developed to investigate free surface
vibrations of cylindrical targets. The target configurations for
RIB and conventional neutrino beams (CNGS project) were
investigated to analyze proton induced thermal stress-wave
generation and propagation. 相似文献
100.
光谱痕量分析的检出限问题 总被引:2,自引:0,他引:2
陈远盘 《光谱学与光谱分析》1994,14(5):105-110
本文研究了光谱分析中的检出限问题。对目前文献中提出的一些检出限的公式进行了归纳和推导。讨论了IUPAC和Long检出限公式的一些实际应用。 相似文献