活性中心

Investigated the organic surface modification of anatase titanium dioxide pigment and its adsorption mode. It was founded that the surface hydroxyl groups are the active centers for olefinic acid. The adsorption of modifier fit Langmuir single molecule layer adsorption mode.

研究了锐钛型钛白的有机表面改性及表面吸附模型，认为表面羟基是有机烯酸表面改性的活性中心，改性剂在钛白表面的吸附符合Langmuir单分子层吸附模型。

LPS is recognized as a main promotor in the pathophysiology of sepsis.

LPS通过其活性中心Lipid A与细胞表面的受体结合，介导脓毒症的发生。

This paper summarized the development of metallocene catalyst and single-site center technology, and introduced the developing trends of polyethylene producing processes including bimodal PE production technology, responser new disposition technology and condensed and super-condensed technology.

概述了茂金属催化剂和单活性中心技术的发展，介绍了聚乙烯生产技术新的发展动向，如双峰PE生产技术、反应器新配置技术、冷凝态和超冷凝态技术。

The cDNA (BplPAL1) encoding phenylalanine ammonia-lyase were cloned from Betula platyphylla by reverse transcription polymerase chain reaction and 5' and 3' rapid amplification of cDNA ends, which contains an open reading frame (2322 bp) encoding 773 amino acids. The amino acid sequences contain two functional domains of PAL-HAL and PAL, and the sequence of enzyme active site, which has 60%~73% of consistency with other five plant species and the consistency with Rhizophora mangle is the highest (73.1%).

利用RT-PCR和RACE技术从白桦中克隆了编码苯丙氨酸解氨酶的cDNA，其2322bp的ORF编码773个氨基酸，其推导的氨基酸序列包含PAL-HAL和PAL2个功能域以及酶活性中心序列GTITASGDLVPLSYIA，该序列同其它5种植物的序列一致性为60%~73%，其中与美洲红树最高为73.1%。

Finally, the article discussed the possible mechanism of multi-phase electrochemical degradation of wastewater through the XPS spectrum of the used catalysts surface: In the acid solutions, the electro-generated O_2 may get electrons on the porous graphite cathode and then form H_2O_2, H_2O_2 may diffused to the surface of catalyst and reacted with its active part to produce OH, which in turn can destruct organics. The catalyst functioned as both the catalyst to decompose H_2O_2 and the flocculants to sedimentate the degraded waste.

最后全文结合研究反应后催化剂表面的XPS光电子能谱推断了该体系降解污废水可能的反应机理：在酸性条件下，石墨双阳极产生的O_2被多孔扩散性石墨阴极还原成H_2O_2，并通过扩散传质作用在催化剂的表面活性中心分解为强氧化性中间产物·OH，强氧化性攻击有机物，使其降解为小分子有机物或CO_2和H_2O，催化剂在体系中即起催化作用也起吸附、絮凝作用。

But the conversion is sensitive to steric effects of half-sandwich titanocene and polymerization temperature.

它能产生更多的活性中心，有利于苯乙烯的间规聚合。

The results were discussed on the basis of steric and electronic effects of the substituents and the stability of the catalytic active sites. New ideas in designing catalysts were presented.

以取代基的立体效应和电子效应的影响及催化活性中心的稳定性为基础对上述结果进行了详细讨论，并根据实验结果提出了设计催化剂的新思路。

The grafting is believed to take place principally through the active centers which are formed on the cellulose substract by the action of eerie ion.

可以认为，接聚反应的发生主要是通过铈离子与纤维素作用在纤维素上生成活性中心。

The valence variety on LaCoO 3 surface in various processes of activation sulfurization was investigated.

然而 ，在SO2 存在下，钙钛矿LaCoO3表面的活性中心发生硫酸盐化而使催化剂失活[2 ] 。

The advantages and shortcomings of the major ex-situ presulfurization technologies are discussed,and the involved sulfurization mechanism and proposed models for active sites are interpreted and analyzed.

讨论了应用于不同加氢处理技术特别是加氢脱硫过程获得的认识。阐述和分析了主要器外预硫化技术的优缺点以及相关的硫化机理、活性中心模型。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。