steric hindrance
英
美
网络 空间位阻; 位阻现象; 空间阻碍; 立体阻碍; 立体障碍
双语例句
- Synthesis and application of lauric acid ester quaternary ammonium salt cationic surfactant in condition of steric hindrance
位阻月桂酸阳离子酯表面活性剂的合成及应用 - Experiments showed that pre-coating with sulfur as a steric hindrance layer or wax as a hydrophobic film on urea surface could effectively prevent urea's dissolving in the coating process.
在聚合物乳液包膜前，先在尿素颗粒表面包覆一层硫磺阻隔层或石蜡疏水层，能有效抑制尿素在包膜时的溶出过程。 - Steric Hindrance Effect on Hydrogenation of Styrene Catalyzed by Ruthenium Hydride Complex
单氢钌配合物催化氢化苯乙烯的位阻效应 - The steric hindrance model was verified to be applicable for the evaluation of the structure of nanofiltration membranes.
结果讨论表明细孔模型适用于纳滤膜的结构评价。 - Their extraction ability markedly decreases with the increase of the steric hindrance from ester alkyl group.
萃取能力随着酯烷基空间位阻的增大而显著降低。 - The size and steric hindrance of substituent of porphyrin is one of the crucial factors to affect the interaction between porphyrins and DNA.
吡啶取代基的大小和空间位阻是影响相互作用方式的关键因素之一。 - This approach covers the substrate range of aliphatic, aromatic, heterocyclic and steric hindrance ketones.
该催化剂适用于各种脂肪酮、芳香酮、杂环酮和位阻酮。 - Excellent dispersing performance of ASP is the result of co-action of electrostatic repulsion and steric hindrance.
ASP良好的分散能力是静电斥力和空间位阻共同作用的结果。 - The effect of steric hindrance and electron on aromatic aldehydes reduced by BER
BER还原芳醛的位阻效应和电子效应 - Development of high-selectivity trimerization catalysts needs the combination of suitable early transition metal in oxidation state and ligands with appropriate electronic structure, space steric hindrance and metastability.
研究表明，一个具有高选择性的三聚催化剂需要选择具有合适氧化态的前过渡金属，以及具有合适电子结构、空间位阻与介稳定性的配体。 - Based on this, the selectivity and steric hindrance for the adsorption of bile acids are discussed.
对树脂吸附胆酸过程中的选择性和位阻作了讨论。 - The results show that the extraction and separation abilities for Yb and Lu decrease with increasing the steric hindrance of the substituents in extractant molecules.
结果表明，这类萃取剂对于Yb，Lu的萃取和分离能力随着其分子中取代基空间位阻的增大而降低。 - The stereoselectivity was improved by increasing steric hindrance of the reactions.
通过增加反应的空间位阻改进了反应的立体选择性。 - The hydrolysis stability would increase when groups around silicon atom or nitrogen atom were of high steric hindrance.
硅原子或氮原子上带有较大空间位阻的基团后，其水解稳定性提高。 - We presumed the possible reason is that high steric hindrance and adopted conformation of molecule are unfavorable to coordinate.
推测是由于分子较大的空间位阻及采取的构象不利于配位所致。 - Thus, we concluded that the steric hindrance of C-terminus might play an important role in opioid receptor affinity.
因此我们推测C-末端空间位阻的大小对于阿片受体的活性可能起着很重要的作用。 - The high activity could be attributed to the high dispersion of Pd ( II) active sites and ordered mesopore channels which effectively diminished the steric hindrance and thus, diffusion limit.
高催化活性归因于Pd（II）活性位的有效分散和规整有序的介孔结构，减小了反应底物的扩散阻力。 - Meanwhile, research revealed that this synthetic route could, in a degree, increase the reactivity of hydrosilylation between reactants with high steric hindrance.
同时，探索研究出了一条在一定程度上能够提高某些高位阻反应物之间硅氢加成反应活性的方法。 - The large steric hindrance group avails to the enantioselectivity, but too much steric hindrance reduces the activity.
大位阻取代基有利于提高对映选择性，但位阻过大降低催化活性。 - On the other hand, the methyl substitution would reduce the polarity of CD cavity. Effect of number and position of methyl substituents on the steric hindrance was important.
与β-CD相比，甲基的引入一方面可以增加空间位阻，另一方面降低了环糊精空腔的极性，取代基的个数和位置是影响空间位阻的重要因素。 - In the synthesis, Span-80 was used as surfactant, due to its steric hindrance effect.
此处使用Span-80为分散剂，是利用其空间位阻作用。 - The effect of steric hindrance on the performance of dechroming was obvious and increasing temperature and associative hydrochloric acid could alleviate the effect degree. The dechroming ability and destructiveness on the stability of collagen of acid groups were bigger than H+.
有机酸分子位阻对其脱铬性能影响较大，升高温度和与盐酸复配均可显著降低其影响程度；有机酸根的脱铬能力及对胶原结构的稳定性的影响均大于H+。 - Finally, we studied the influence of steric hindrance to the reaction.
最后，研究探讨了空间位阻对该反应的影响。 - In the end, the steric hindrance of the substitute was discussed.
最后，讨论了清除过程中取代基的空间位阻效应。 - We researched the effects of adding order of two monomers to the molecular weight and PDI, and illustrated that it was caused by the steric hindrance of this protection group.
研究了两个单体聚合的先后顺序对得到的嵌段共聚物分子量及分子量分布的影响，阐明了该影响是保护基团的空间位阻原因造成的。 - Also we used oxygen to replace the acetyl acetone base to minimize space steric hindrance to improve activity.
另外，还采用氧替换乙酰丙酮基的方法以减小有机钛化合物空间位阻来提高催化活性。 - The selectivity of this reactions depended on the steric hindrance of the electrophilic groups.
并且通过进一步的研究发现，该反应的顺反选择性，取决于亲电基团的位阻大小。 - It was found that dual fluorescence of MS closely correlate with the hydrogen bonding property of its surrounding microenvironment. The sizes of substituents at the rim of β-CD result in different polarity and steric hindrance at the cavity opening.
结果表明，MS的双重荧光与所处微环境的氢键性质密切相关，β-CD取代基的大小会导致空腔口处的极性和空间位阻不同，相应改变了分子间氢键相互作用。 - We also found that the ortho ester functional groups have an accelerating effect for the reaction to proceed and the steric hindrance effect of ester is not apparent.
研究还发现邻位酯基对反应的进行有明显的促进作用，而酯基的空间位阻效应对反应影响不明显。 - The electronic effects of the substituents on the benzene ring and the steric hindrance do not significantly alter the reaction time and yield.
反应时间和反应收率不明显受苯环取代基团电子效应及空间位阻的影响。