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排序方式: 共有7177条查询结果,搜索用时 46 毫秒
41.
Rivard C. J. Himmel M. E. Vinzant T. B. Adney W. S. Wyman C. E. Grohmann K. 《Applied biochemistry and biotechnology》1989,(1):461-478
Economic evaluations of the capital costs for anaerobic digestion systems for gas production show that the reactor is a significant
cost component. The successful application of high solids digestion of processed MSW (e.g., greater than 10% solids within
the digester) would allow a decrease in reactor volume with maintenance of relatively high gas production rates. However,
high solids slurries do not mix well in conventional stirred tank reactors. A horizontal shaft, hydraulically driven reactor
was designed and fabricated to test the anaerobic digestion of high solids concentrations. Digester performance was evaluated
as a function of experimental parameters such as nutrient requirements, feeding rates, pH control, and agitator design/ rotation
speed; horsepower of mixing was also evaluated for the reactor. Several startup protocols were examined to obtain a biologically
stable anaerobic fermentation at high solids levels. 相似文献
42.
Designing an Immobilized Metal ion Affinity (IMA) chromatographic process on large scale demands a thorough understanding to be developed regarding the adsorption behaviour of proteins on metal loaded IMA (IMA-M(II)) gels and the characteristic adsorption parameters to be evaluated. This research investigation illustrates the significance of these aspects for the proposed fractionation of chicken egg-white proteins on these gels. Consequently, a systematic investigation of the adsorption characteristics of three chicken egg-white proteins viz., ovalbumin, conalbumin and lysozyme on Cu(II) and Ni(II) loaded IMA gels, iminodiacetate (IDA) and tris(2-aminoethyl)amine (TREN), has been undertaken. These gels differ in their selectivity towards the proteins of interest under the identical sets of experimental conditions. While TREN-Ni(II) was selective only for lysozyme, IDA-Cu(II), IDA-Ni(II) and TREN-Cu(II) showed varying affinities for all the three proteins. The equilibrium and kinetic data were analysed using various theoretical models and adsorption parameters were quantified. On the basis of these investigations, various strategies have been proposed for the efficient large-scale fractionation of chicken egg-white proteins on these gels. 相似文献
43.
Patricia Cava-Montesinos Agustin Pastor Miguel de la Guardia 《Analytica chimica acta》2003,481(2):291-300
A sensitive procedure has been developed for selenium and tellurium determination in milk by hydride generation atomic fluorescence spectrometry (HG-AFS) after microwave-assisted sample digestion. The method provides sensitivity values of 1591 and 997 fluorescence units ng−1 ml−1 with detection limits of 0.005 and 0.015 ng ml−1 for Se and Te, respectively. The application of the developed methodology to the analysis of cow milk samples of the Spanish market evidenced the presence of concentration ranges from 11.1 to 26.0 ng ml−1 for Se, and from 1.04 to 9.7 ng ml−1 for Te having found a good comparability with data obtained after dry-ashing of samples. 相似文献
44.
Henriques ES Floriano WB Reuter N Melo A Brown D Gomes JA Maigret B Nascimento MA Ramos MJ 《Journal of computer-aided molecular design》2001,15(4):309-322
We present the search for a new model of -factor XIIa, a blood coagulation enzyme, with an unknown experimental 3D-structure. We decided to build not one but three different models using different homologous proteins as well as different techniques and different modellers. Additional studies, including extensive molecular dynamics simulations on the solvated state, allowed us to draw several conclusions concerning homology modelling, in general, and -factor XIIa, in particular. 相似文献
45.
In this study, we report the design and synthesis of a series of new simplified fumitremorgin C analogues. The preliminary biological study indicated some of these simplified fumitremorgin C might be developed into breast cancer resistance inhibitors. 相似文献
46.
采用微波消解ICP-AES法同时测定了茯苓、桑黄和桦褐孔菌子实体中Ca、Mg、Fe、Zn、Cu、Mn、Se和Cr 8种微量元素。结果显示,3种药用真菌中均含有这8种元素,其中茯苓样品中Ca和Fe含量最高,为212.36μg.·g 1和164.08μg.g-1;桑黄样品中Mn、Zn和Se含量最高,为22.62μg.g-1、91.03μg.·g 1和2.68μg.g-1;而桦褐孔菌样品中Mg、Cu和Cr含量最高,分别是953.60μg.g-1、10.25μg.g-1和2.59μg.·g 1。检出限<0.008μg.mL-1,方法简便、可靠,具有良好的精密度和准确度。 相似文献
47.
密闭微波消解-冷原子荧光光谱法测定蔬菜中的痕量汞 总被引:1,自引:0,他引:1
采用硝酸和过氧化氢体系,密闭微波消解,冷原子荧光光谱法测定蔬菜中的痕量汞,选择0.3g/L硼氢化钾溶液为还原剂,硝酸溶液(1 99)为酸介质。测定结果表明汞浓度在0~1μg/L范围线性良好,相关系数大于0.9990,汞的加标回收率为90.2%~99.6%,测定结果的相对标准偏差均小于4%,检出限为0.0058μg/L。 相似文献
48.
微波消解-火焰原子吸收光谱法测定兰州鲶中微量元素 总被引:3,自引:0,他引:3
使用微波消解处理样品,火焰原子吸收光谱法测定了兰州鲶中的铁、锌、镁含量。结果显示,兰州鲶中含有丰富的铁、锌、镁三种人体必需微量元素。该法测定快速、简单,结果满意。 相似文献
49.
50.
微波消解ICP-AES法测定玩具塑料中镉 总被引:9,自引:0,他引:9
采用微波加压消解溶样,ICP-AES法测定玩具塑料中镉含量,选择最佳工作条件,方法简便、快速、可靠。适用于各类玩具塑料中镉含量的分析。 相似文献