查询词典 constants

The equilibrium constants k t/ k c of photochemical back-isomerization reaction of G1 are 1.76～1.77 approaching to 1, and thus it is appliable to photoswitch material.

G1的光回复异构化反应平衡常数 k t / k c为1.76～1.77，有作为光控开关材料的应用前景。

All the parameteres of the mechanical autofrettage can be obtained directly by the excess δ, the geometric size and the material constants using this method.

使用本文所提出的方法只需要过盈量δ、几何尺寸和材料性能参数即可直接求得机械自紧所需各项参数。

To certain degree, the larger the physical and total quenching rate constants, the better the anti-fading effect of magenta azomethine dye.

物理猝灭速度常数和总猝灭速度常数愈大，在一定范围内，品红甲亚胺染料的防褪色效果愈好。

The molar extinction coefficient, maximum absorption wavelength, reaction rate constants of trans-cis photochemical isomerization, thermal back-isomerization and photochemical back-isomerization and equilibrium constant of photochemical back-isomerization reaction of a novel photochromic liquid crystalline dendrimer G1 of the first generation containing nitroazophenyl groups on its periphery and small molecular azophenyl moiety M1 in solution were described.

张其震*1，盛昕1，李爱香1，王艳2摘要：研究了树外围含12个硝基偶氮苯基元新型一代碳硅烷光致变色液晶树枝状大分子G1和基元小分子M1在溶液中的最大吸收波长、摩尔消光系数、反-顺光化学异构化反应速率常数、热回复异构化反应速率常数、光化学回复异构化反应平衡常数及速率常数。

The four reaction channels including hydroxyl-type benzaldoxime are endothermic reaction, thermodynamically non-spontaneous process, but the other four reaction channels including ion-type benzaldoxime participation are exothermic reaction and thermodynamically spontaneous process. The latter four reaction channels, which have lower reaction barriers, faster reaction velocities and bigger equilibrium constants than those of the former fours, are the chief reaction channels.

苯甲醛肟以羟基型参与反应的4个反应通道均为吸热反应和热力学非自发过程，它们均具有较高的反应势垒、较慢的反应速率和较小的平衡常数；而以离子型参与反应的四个反应通道均为放热反应和热力学自发过程，它们的反应势垒较低，反应速度较快，平衡常数也较大，故苯甲醛肟应主要以离子型参与反应。

The ultraviolet-visible absorption spectra, optical constants (complex refractive index N=n+ik) of the thin films and thermal characterizations of three kinds of novel nickel-azo dyes based on 4-methylthiazole, benzothiazole and 6-methylbenzothiazole were investigated.

分别对三种以 4 甲基噻唑、苯并噻唑和 6 甲基苯并噻唑作为重氮组份，以 3 二乙氨基苯酚作为偶合组份的偶氮染料的镍螯合物的光谱、热学性质和薄膜的光学常数(复折射率N =n+ik)及光存储性能进行了研究。

The ultraviolet-visible absorption spectra, optical constants (complex refractive index N=n+ik) of the thin films and thermal characterizations of three kinds of novel nickel-azo dyes based on 4-methylthiazole, benzothiazole and 6-methylbenzothiazole were investigated.

分别对三种以4-甲基噻唑、苯并噻唑和6-甲基苯并噻唑作为重氮组份，以3-二乙氨基苯酚作为偶合组份的偶氮染料的镍螯合物的光谱、热学性质和薄膜的光学常数及光存储性能进行了研究。

From the results of time resolved measurements on the NCO radicals, the bimolecular rate constants for the reactions of NCO with SO2 and CS2 were obtained as (1.8±0.3)×10^(-11) and (3.1±0.4)×10^(-12)cm^3molecule^(-1)s^(-1), respectively.

得到了NCO自由基与SO2、CS2双分子反应速率常数分别为(1.8±0.3)×10^(-11)和(3.1±0.4)×10^(-12)立方公分molecule^(-1)s^(-1)。

The bimolecular electron transfer rate constants demonstrate a marked dependence on ionic strength. This indicates that the electrostatic interaction plays significant role in the electron transfer.

电子传递速率常数的对数与离子强度符合指数关系，表明静电作用在电子传递过程中起着较重要的作用。

The tryptophan residues play important roles in DNA photoreactivation catalyzed by CPD photolyases. We have investigated the action mechanism concerning Trp in DNA photoreactivation, and obtained the results as follows: 1 We proposed a mechanism of photosensitized splitting of CPDs by Trp and Trp-containing peptides. 2 Quantum yields of splitting of the model compounds that a Trp linked covalently a CPD were obtained under 290 nm light in various solvents, these values changing with solvent, range from 0.01 to 0.5. 3 Utilizing pulse radiolysis technique, splitting processes were observed in aqueous solution of the CPDs with hydrated electron and some oxidative species (such as hydroxyl radical, bromic radical and azide radical), and obtained their rate constants. In the case of interaction between CPD and hydrated electron, splitting of the CPD anion, and pyrimidine anion transfer an electron to FAD or Rf, were observed. The process rate was slower one order more than that in photolyase. Minor, but highly mutagenic UV-light-induced lesions are (6-4) photoproducts, which are repaired by (6-4) photolyases. These enzymes, discovered in 1993, are not well characterized and their mechanism is still under investigation.

我们研究它的作用机理，获得以下结果：1）建立了色氨酸及其肽对嘧啶二聚体光敏化裂解的直接修复作用机理模型；2）获得了色氨酸共价键连接于嘧啶二聚体的化合物在多种溶剂中290nm光辐照裂解的量子效率，其值随溶剂而变化，范围在0.01-0.5；3）运用脉冲辐解观察到嘧啶二聚体与水合电子和一些氧化性的自由基作用裂解过程，得到相应速率常数；对二聚体与水合电子作用发生裂解以及向FAD返还电子的过程进行了体外模拟；4）（6-4）光解酶的作用机理中一个关键假定是氧杂环丁烷中间体在接受电子后能自发裂解，恢复二嘧啶的结构。

We are forbidden from giving money to these shoeless, skinny children, as this will perpetuate begging.

向光着脚，骨瘦如柴的孩子施舍是不可以的，因为要招来无休无止的乞讨。

It would be hard not to fall victim to some sharpeyed policeman.

要想不被某个目光锐利的警察抓到，谈何容易。