查询词典 ion-pair

The effect of zeolites ion-exchanged by transition metals on thermal catalytic cracking reaction is studied. The product distributions of the cracking reactions catalyzed by theβor ZSM-5 zeolites exchanged with transition metals are different from that catalyzed by corresponding Hzeolites, which means the mechanism of cracking reactions has varied. Group Ⅷ metals Fe, Co, Ni and Cu, Zn are shown to be of strong catalytic activity of oxidative dehydrogenation, while Ti and Cr are not of oxidative activity. Catalyzed by zeolites or catalyst containing Ag, conversion of thermal catalytic cracking reactions and the yield of ethylene increase while the yield of propylene does not decrease. Silver can not only promote the formation of carbonium ion, but also convert carbonium ion into free-radical via redox reaction. The weak adsorption of olefins on silver reduces the occurrence of hydrogen transfer and dehydrogenation. As a result, the yield of light olefins is favored by silver in the catalyst.

采用过渡金属交换的分子筛作为催化剂，进行催化热裂解制取乙烯的反应，研究发现，在β沸石分子筛和ZSM-5分子筛中引入过渡金属后，催化热裂解反应的产物分布与相应的氢型分子筛相比有了较大的变化，说明过渡金属的加入对于催化热裂解反应的机理具有影响，Ⅷ族金属如Fe、Co、Ni和第Ⅰ、Ⅱ副族Cu、Zn表现出较强的氧化脱氢活性，产物中氢气、焦炭的产率很高，Ti、Cr则未表现出氧化作用：分子筛及催化剂中引入银后，催化热裂解反应的转化率和乙烯的产率有了提高，丙烯产率没有很大的变化，说明银在催化热裂解反应中能够促进正碳离子的生成，又有可能通过氧化-还原作用部分改变反应机理，促进了自由基的生成，并且由于银对烯烃的吸附很弱，其氢转移反应和脱氢、加氢活性比较低，有利于烯烃产率的提高。

The ability of electrochemically switched ion exchange depends largely on the concentration of ion,the ion type and scan rates.

溶液中离子的浓度、离子的种类是膜内阳离子交换的主要影响因素。

The results showed that the kinetical rule of the ion-exchange reaction was not changed, the ion-exchange process was still controlled by the grain diffusion, and the concentration of Cl~- has little effect on the apparent activation energy of reaction if the total concentration of ion in the solution kept invariableness.

结果表明，在维持溶液中离子总的当量浓度不变的条件下，离子交换反应的动力学规律不会发生改变，反应仍然是受粒扩散控制，氯离子浓度对交换反应表观活化能的影响不大。

It was found that dimolybdate ion did not exist in the saturated aqueous solution and was transformed into heptamolybdate ion Mo7O24^6- as the predominant species and monomolybdate ion MoO4^2- as the secondary species.

提出了一种利用Raman光谱主要特征峰振动频率及其主、次特征峰强度之比值对二钼酸铵晶体饱和水溶液组分同时进行定性和半定量分析的新方法。

Ion chromatography using pellicular ion exchange resins and dilute solution can be devoted to the study of ion exchange thermodynamics and kinetics.

离子色谱法采用薄层离子交换树脂和稀溶液体系，可以作为研究离子交换热力学和动力学的理想手段。

The possible reason is that doped Zr〓 ion enters the interstitial sites for its small ionic radius and no dipole complexes were formed. Monovalent ion F〓 has been reported to improve the scintillating performance greatly. Our results show that Agrand diagrams of F〓: PWO crystals obey an modified Cole-Cole equation. The crystals present similar dielectric relaxation phenomena to but have much higher activation energy than that of RE〓: PWO crystals, which originate from the 〓 dipole complexes. The co-doping of trivalent Y〓 and pentavalent ion Nb〓 does not always show a better scintillation performance than that of solely doped samples, which could be attributed to the existence of the 〓 dipole complexes, which counteract the solely doping effect.

而Zr〓由于离子半径太小，可能进入间隙位置，不形成类似的偶极缺陷；一价负离子F〓的掺入提高了晶体闪烁性能，阻抗谱测试结果表明F〓：PWO晶体Argand图符合修正的Cole—Cole方程，晶体同样表现出介电弛豫现象，并具有比RE〓：PWO晶体中高得多的弛豫激活能，可能起源于形成的〓偶极缺陷；Y〓和Nb〓双掺的PWO晶体并没有显示出两种离子单掺优点的叠加，阻抗谱测量结果表明，在双掺晶体中可能形成〓偶极缺陷，使两者掺杂作用相互抵消。

Based on the research results, the shot peening+ion sulphurization and ion nitriding+ion sulphurization duplex treatments were used to treat the steel surfaces, the effect of sulphide layer could be further developed.

依据研究结果，对钢铁表面进行喷丸+离子渗硫、离子渗氮+离子渗硫复合处理，以进一步发挥渗硫层的作用。

Through analysis of the actuality and existent questions about low voltage reactive- power compens AT ion controller used traditionally, This paper introduced the working theory of the system based Micro-controller AT 89C52 and canbus, communic AT ion configur AT ion technology of CAN fieldbus and the implement of software and hardware.

在分析传统低压无功补偿控制器现状和存在问题的基础上，提出一种基于单片机 AT 89C52的 CAN 总线实现的低压无功补偿的实施方案。介绍了其工作原理， CAN 总线通讯组态技术，以及系统硬件和软件实施方案。

In addit ion , average angular informat ion is taken from adjacent segments and the incident ion beam

另外，可以从邻近线段和入射离子束取得平均角度的信息。

In which a continuous stream of sea water is divided into desalted and concentrated streams by ion concentration polarization, a phenomenon that occurs when an ion current is passed through ion-selective membranes.

负责这项研究的麻省理工大学研究人员JongyoonHan称，这种芯片可以将海水和苦咸水中的细菌和其他粒子分离出去，而且不会产生任何堵塞问题。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。