Study on Bifunctionality of Mo/HZSM-5 Catalysts for Methane Dehydro-Aromatization under Non-oxidative Condition

The optimum Mo/[H~+] ratio per unit cell of the active precursors in Mo/HZSM-5 catalysts for methane dehydro-aromatization, measured by 1H MAS NMR, was found to be about 1 when adjusting the acid sites by altering either the SiO2/Al2O3 ratios or the Mo loading. This implies that a concerted interaction between the Mo species and the Bronsted acid sites probably features the bifunctionality of the Mo/HZSM-5 catalyst. On the other hand, it was found that the driving force for Mo species to move into the HSZM-5 zeolite channels and the interaction between the Mo species and the Bronsted acid sites are closely and proportionably related with the amount of Bronsted acid sites per unit cell.     

在H型分子筛上萘与正己醇的烷基化反应

制备了H型分子筛HY,Hβ和HM,通过XRD,NH₃-TPD和Py-IR对其进行了表征,考察了其对萘与正己醇的烷基化反应的催化性质.结果表明,HY可作为己基化反应的催化剂,较高的反应温度和较长的反应时间对β-己基萘的生成有利.     

0.6~T人体核磁共振成象及其图象的彩色化处理

在0.6~τ超导磁体人体核磁共振成象设备上获得了横断、矢状、冠状各种断层的成象。采用了直接两维傅里叶变换成象方法,应用了自旋回波脉冲序列。由于人体心脏跳动和呼吸运动会造成图象模糊而使用心电延迟触发及呼吸门控方法。作者用一种相位调制光密度分割的方法将原始黑白灰度表示的核磁共振成象进行彩色化处理。提高了原图象低密度梯度区的清晰度,为进行医学图象诊断及判读解译提供了方便度。山了光学系统图,解释了光学信息处理方法。由所处理的人体核磁共振成象图片可以看出,在低密度梯给区更易辨认。参考文献10种。     

稀土苦味酸配合物的合成及其结构研究

合成了15种稀土苦味酸配合物,进行了元素分析,并测定了振动光谱、XPS谱和X射线单晶衍射的晶胞参数,对配位情况和金属-氧键的性质进行了计论。     

毛细管气相色谱法分析蜂王浆制剂中的10-羟基癸烯-2酸

本文介绍了一种用毛细管气相色谱定性定量测定蜂王浆制剂中10-HDA含量的方法。样品经预处理后,提取物同硅烷化试剂BSTFA进行衍生化反应,反应产物经由交联SE-30石英毛细管柱分离。该法衍生化反应简单、快速、分离完全,可用于分析蜂王浆及其它蜂王浆制剂。     

不同波长紫外光照下纳米TiO2薄膜的光致亲水性与循环伏安行为

通过溶胶-凝胶方法分别在ITO和玻璃表面制备了纳米TiO_2薄膜，研究了纳米 TiO_2薄膜在254及365nm的紫外光照射下的循环伏安行为和光致超亲水性。在紫外 光的照射下，TiO_2薄膜电极可表现出两个光电化学过程，纳米TiO_2薄膜的光致超 亲水性转变及两个光电化学过程的速率均取决于紫外光的波长，原因在于纳米 TiO_2薄膜对两种波长的光的吸收率和光子的能量不同。提出了光电化学过程的机 理，认为紫外光照射下纳米TiO_2薄膜的超亲水性变化与产生Ti~(3+)的过程引起的 表面微观结构变化存在的一定的内在联系。     

聚合-β-环糊精作手性选择剂的毛细管电泳法分离4种光学活性农药中间体

以聚合-β-环糊精作为毛细管区带电泳手性选择剂,成功分离了2-苯氧丙酸(PPA)、顺式-功夫菊酸(cis-PA)、1-苯基-2-(对甲苯基)乙胺(PTE)和1-苯基-2-(对甲氧基苯基)乙胺(PME)4种光学活性农药中间体的对映体。考察了不同手性选择剂及其浓度、背景电解质的pH等操作条件对分离的影响。结果表明,在12kV操作电压下、30mmol／Ltris-HCl背景电解质中,用14g／L聚合-β-CD作为手性选择剂,PPA和cis-PA对映体在pH6．0时,PIE和PME对映体分别在pH2．5和pH3．0时可以被较好分离。在优化的分离条件下,用聚合-β-CD作毛细管区带电泳手性选择剂分离PIE对映体的分离度为1．513,成功测定了两种旋光性PIE的对映体过量值。     

Determination of human IgG by solid-substrate room-temperature phosphorescence immunoassay based on an antibody labeled with nanoparticles containing rhodamine 6G luminescent molecules

Luminescent 50-nm silicon dioxide nanoparticles containing both types of rhodamine 6G (R; particles denoted R-SiO₂) were synthesized by the sol–gel method. In the presence of Pb(Ac)₂ as a heavy atom perturber the particle can emit the intense and stable room-temperature phosphorescence (RTP) signal of R on a polyamide membrane, with _ex^max/_em^max=470/635 nm for R. Our research indicates that the specific immune reaction between goat-anti-human IgG antibody labeled with R-SiO₂ and human IgG can be carried out quantitatively on a polyamide membrane, and the phosphorescence intensity was enhanced after the immunoreaction. Thus a new method for solid-substrate room-temperature phosphorescence immunoassay (SS-RTP-IA) for determination of human IgG was established on the basis of antibody labeled with the nanoparticles containing binary luminescent molecules. The linear range of this method is 0.0624–20.0 pg spot^–1 of human IgG (corresponding to a concentration range of 0.156–50.0 ng mL^–1, sample volume 0.40 L spot^–1). The regression equations of the working curves are I_p=71.27+7.208m_IgG (pg spot^–1) (r=0.9996). Detection limits calculated as 3S_b/k are 0.022 pg spot^–1. Compared with the same IA using fluorescein isothiocyanate (FITC) as the marker the new method was more sensitive and had a wider linear range. After elevenfold replicate measurement RSD are 4.5 and 3.6% for samples containing 0.156 and 50.0 ng mL^–1 IgG, respectively. This method is sensitive, accurate, and of high precision.     

ENTROPIC CONTRIBUTION TO THE INTERACTION PARAMETER xIN THE POLYMER／OLIGOMER SYSTEM： A LATTICE CLUSTER THEORY CONSIDERATION

Entropic contribution to the interaction parameter xeff in the model incompressible polymer/oligomer system is calculated by the lattice cluster theory (LCT). It is found that in the oligomer solvent, there exists a wide concentration range that the non-combinatorial “entropic interaction” term xeff φ1φ2 perceptibly counteracts the mean field combinary entropy ΔSMF. With the increase of the solvent size, both xeff and the ratio xefc φ1φ2/ΔSMF first reach their maximum and finally become trivially to zero. It is worth noting that no any demixing was found in the current calculation. This makes the controversial idea “entropically driven demixing” even elusive. However, we propose that further work on compressible polymer solution with structured monomer will witness the demixing owning to an increased configurational correlation.     

芳香族小分子物质在表面活性剂溶液中的状态

阴、阳离子表面活性剂在水溶液中混合后很容易形成沉淀,因而以往在应用上将这两种表面活性剂视为配伍禁忌。但是最近几年,混合阴、阳离子表面活性剂水溶液理论性质的研究受到了一种程度的重视。研究发现,该混合体系具有与单纯的离子型表面活性剂或离子与非离子型表面活性剂混合物十分不同的性质,