查询词典 selectivity

The results showed that, the adsorption selectivity of thiophene on CeY was better and on NaY was poorer.

CeY对噻吩具有较好的吸附选择性，而NaY的吸附选择性不好。

It shows a thousandfold selectivity for fluoride over other common anions.

它对氟离子的选择性比其它普通阴离子高几千倍。

The whole analysis was completed on a C〓 column in 18min at a flow rate of 0.5 ml/min, with the mobile phase of methanol-water (93: 7, v: v) containing 75 mmol/L TEOLA and 200 mmol/L HAc, or with the mobile phase of ethanol-water (90: 10, v: v) containing 25 mmol/L TEOLA and 200mmol/L HAc pumped at 0.25ml/min. Compared with the methanol system, the ethanol system was a better candidate for the separation of thulium porphyrin complexes in view of selectivity.

在C〓分析柱（5μm，2.5×150mm）上，流动相为：甲醇：水＝93：7（v/v内含75mmol/L三乙醇胺和200mmol/LHAc），流速为0.5ml/min和流动相为：乙醇：水＝90：10（v/v，内含25mmol/L三乙醇胺和200mmol/L HAc），流速为0.25ml/min，均能使六个铥卟啉配合物在18min内得到有效的分离，相比之下，乙醇体系对铥卟啉配合物更具有分离选择性。

Phenyl or m -tolyl selenoamides reacted with functionalized α-haloacetic acid in 1∶1 or 1∶2 molar ratio with no catalyst in various alcohols to undergo a selenium transfer reaction. This reaction in dif-ferent molar ratios furnished the same C—Se—Se—C coupling products with a special structure bis diselenide. A new and facile method for synthesis of such bis(alkoxycarbonyl-methyl) diselenides with the advantages of mild reaction conditions, high yields, easy availability of starting materials and good chemical selectivity was provided.

芳基硒代酰胺与氯乙酸在各种醇中无催化剂下以1∶1和1∶2的比例投入，发生硒转移反应，不同原料投入比下的反应生成了同一种C—Se—Se—C偶联产物——具有多功能团的二烷氧羰基甲基二硒醚，提供了一种新的合成二烷氧羰基甲基二硒醚的简便方法，且反应具有条件温和、产率高、原料易得和选择性好等优点。

The oligomerization of isoprene with titanium tetrachloride as catalyst and alkylaluminium chlorides as promotor was studied, and especially the effects of the reaction conditions on the synthetic activity and selectivity of dimer and trimer were investigated in detail.

研究了以四氯化钛为主催化剂，以烷基铝为助催化剂催化异戊二烯的低聚反应，详细考察了各种反应条件对催化合成二聚体及三聚体的活性和选择性的影响。

The optimum conditions and the influence factors were investigated, and the composition of ion-association complexes and the reaction mechanism were also discussed. The effects of foreign substances were tested and it is shown that the method has a good selectivity. Based on HgCl2 and basic triphenylmethane dye, the sensitive, simple and rapid method for the determination of trace CTRX was developed.

研究了适宜的反应条件和影响因素，对离子缔合物的组成和离子缔合反应机理进行了探讨，考察了共存物质的影响，表明方法有良好的选择性，据此发展了用HgCl2和碱性三苯甲烷类染料的灵敏、简便、快速测定痕量头孢噻肟钠的新方法。

And a cascade trisection filter with high selectivity in upper stopband is proposed.

此外，文中也提出了如何快速设计具高止带频率选择性的串接三角互耦滤波器。

The unnoble metal Cobalt catalysts were selected in the reaction system. The study was both of theoretical significance of selective hydrogenation and practical significance of making full of abound bay oil resources in GuangXi province. Cobalt-based catalysts of Co-La/Al2O3 modified by La and Co-Fe/Al2O3 modified by Fe were prepared by impregnation. The selectivity and activity of catalysts were elvaluated with active test.

本工作是国家自然科学基金课题"α，β-不饱和醛选择加氢为不饱和醇多相催化剂的研究"(编号：20266001)的重要组成部分，选择的是非贵金属钴催化剂体系，该研究对于发展选择性催化加氢和充分利用广西丰富的桂油资源具有重要的理论和现实意义。

In the pervaporation-aided esterification of valeric acid with ethanol, the valeric acid conversion is up to 95. 2%. The data about M5 selectivity and flux are measured for poly-component reacting system.

应用本文研制的化学改性聚酰亚胺膜，研究了渗透蒸发分离过程在戊酸乙酯合成反应中的应用，实验得到的戊酸最大转化率是95.2%，并研究了膜对多元反应物系的选择性，及膜的透过量。

The valine modified electrode showed good sensitivity, selectivity, stability. It was applied to the NE injection sample analysis.

修饰电极具有良好的灵敏度、选择性和稳定性，可用于去甲肾上腺素针剂样品分析。

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％。