sn2

Study of the quantum chemistry model of sn2 ' and Se 2 ' reaction transition states

SN2′和SE2′反应过渡态的量子化学模型探讨

Sn2 - plays the role of sensitizer in silvering reaction .

在镀银反应中，Sn~（2-）起着敏化剂的作用。

Antioxidant can effectively prevent Sn2 + in the bath from being oxidated ;

抗氧化剂能有效地防止镀液中Sn~（2+）的氧化；

In my thesis the anion and ion-pair SN2 reactions at carbonhave been studied .

本论文主要研究了碳原子上阴离子和离子对的SN2反应。

The underpotential deposition ( UPD ) of Sn2 + on gold disc electrode was studied using cyclic voltammetry .

用循环伏安法研究了Sn2+在金盘电极上的欠电位沉积。

The results indicate that most Sn2 + permeate into the pore canal of bamboo charcoal by restoring to the original state Sn .

结果表明：Sn2+大部分进入到竹炭的孔道中，并且被还原为单质Sn。

With the deformation of the Ag matrix , Sn2 particles can insert continuously into the Ag matrix and finally accomplish the homogenous dispersion .

随着Ag基体的变形，SnoZ颗粒会不断的嵌入到银基体中，最终完成均匀弥散。

Meanwhile the doping amount of TiO2 / Sn2 + , the initial concentration of illumination time have important effect on the degradation of formaldehyde which were determined .

讨论了TiO2/Sn2+的掺杂量、甲醛的初始浓度、光照时间等因素对涂料降解甲醛效率影响。

When Sn2 + concentration in the bath is higher , the dispersive ability of the bath decreases and the surface quality of the deposits sets worse .

Sn~（2+）浓度过高，镀液分散能力降低，使镀层的表面质量下降。

Al3 + , Mg2 + , Sn2 + , sugar , NaCl and sodium benzoate have hyperchromic effects .

而Al3+、Mg2+、Sn2+离子，蔗糖，食盐和苯甲酸钠则有不同的增色作用。

The stability of colloidal pd2 + and Sn2 + activation solution mainly depends on the concentration of pd2 + and Sn2 + .

实验中发现胶体钯活化液的稳定性主要取决于Pd2+和Sn2+的浓度。

Studies on the SN2 reaction of the side chain group in the polymer-syntheses of ethyl α - methylacrylate asymmetric resins containing chiral α - amino acid ligands

聚合物侧基的双分子亲核取代反应&含α-氨基酸手性配体的丙烯酸酯类不对称配位树脂的合成

Can generate is relatively stable carbon-left groups and the response of vulnerable SN1 , central carbon atom space hampered the response of small-prone SN2 .

能生成相对稳定的正碳离子和离去基团的反应物容易发生SN1，中心碳原子空间阻碍小的反应物容易发生SN2。

The addition of metal ions to the catalytic system improved the activity and selectivity in different degree ( except Sn2 + selective reduction of m-CAN ), The different metal ions have different effects .

结果表明，这4种金属离子不同程度的提高了PVP-4Pt/1Ru胶体的活性和选择性（除Sn2+对m-CAN选择性降低外），不同的金属离子对PVP-4Pt/1Ru胶体的修饰作用不同。

The BST films with 15mol % Sn2 + dielectric constant was 420 , which was higer than that non-doped BST thin films .

以Sn~（2+）为掺杂源，其最佳掺杂量为15%mol，在此掺杂量下，BST薄膜的介电常数为420，高于未掺杂薄膜，介电损耗为0.1。

A new highly convenient route for the core trisaccharide of N-glycans construction was found by the SN2 inversion method . And it is the most convenient route which has been reported until now .

最后通过分子内SN2亲核反应法找到了一条高效构建N-糖链核心三糖的新路线，这也是迄今已报道的最简洁高效的路线。

Magnetic field also did not influence the following cathodic processes : O2 diffusion , Sn2 + reduction , Sn2 + diffusion and H + reduction on Sn-plated surface , but influenced H + reduction on iron .

磁场也不影响阴极过程中O2扩散，Sn~（2+）还原、Sn~（2+）扩散、镀Sn层上氢还原等反应，但会影响Fe上氢还原反应。

The mechanisms of the hydrolysis were proposed to be unimolecular nucleophilic substitution and bimolecular nucleophilic substitution ( SN2 ) . On the Problem of Bimolecular Nucleophilic Substitution Reaction Sterochemistry

水解反应的可能机理是SNl和SN2.双分子亲核取代反应立体化学问题释疑

The activation energy and rate constant of the allylation reaction was calculated in virtue of kinetic study . The kinetics study indicated that the allylation reaction of polyether was second order and its reaction mechanism was SN2 nucleophilic substitution .

进行了动力学研究，获得了反应活化能和各反应温度下的反应速率常数，同时研究结果表明烯丙基化反应级数为2，反应机理为SN2亲核取代反应。

The Sn - Ag alloy series electroplating solution containing Sn2 + compound , Ag + compound , chelating agent and additive etc. is discussed . The electroplating solution has excellent stability and is suitable for solderability surface finish of electronic parts .

叙述了由Sn2+化合物、Ag+化合物、螯合剂和添加剂等组成的Sn-Ag合金系电镀液，该镀液具有优良的稳定性，适用于电子部件的可焊性表面精饰。

Sucrose , salt , sodium benzoate and most of metal ions had no negative effects on the stability of the pigment , but Fe3 + 、 Fe2 + 、 Cu2 + 、 Pb2 + and Sn2 + accelerated the pigment degradation .

食品基质蔗糖、食盐，防腐剂苯甲酸钠及多数金属离子对该色素的稳定性无不良影响，但Fe3+、Fe2+、Cu2+、Pb2+、Sn2+对色素具有不利的影响。

Advance adsorption of Sn2 + on the surface of silica nanowires is helpful for the forming of tiny and dense silver nuclei , as a result , denser and evener silver coating layer can be formed through the method of pretreatment electroless silver deposition .

Sn2+在氧化硅纳米线表面的预先吸附有利于细小、密集银核的形成，所以预处理化学镀法能形成更密集、更均匀的银包覆层。