Adsorption, desorption and activities of acid phosphatase on various colloidal particles from an Ultisol

Adsorption, desorption and activity of acid phosphatase on various soil colloidal particles and pure clay minerals were studied. Higher adsorption amounts and low percentage of desorption of acid phosphatase were found on fine soil clays (<0.2 μm). Electrostatic force and ligand exchange are the major driving forces that are involved in the adsorption of enzymes on soil clays. More enzyme molecules were adsorbed on soil clays in the presence of organic components. However, enzymes on organic clays were more easily released. One-third of the enzyme on goethite was adsorbed via ligand exchange process. Some other interactions, such as van der Waals force, hydrophobic force and hydrogen bonding may be more important in the adsorption of enzyme on kaolinite and the enzyme in this system cannot be easily removed. Coarse clays (0.2–2 μm) and inorganic soil clays had higher affinities for enzyme molecules than fine clays and organic clays, respectively. The activity of enzyme bound on soil clays was inhibited and the thermal stability was increased in the presence of organic matter. Data obtained in this study are helpful for a better understanding of the interactions of enzymes with inorganic and organic constituents in soil and associated environments.     

Controlling the agglomeration of anisotropic Ru nanoparticles by the microwave-polyol process

A rapid polyol process for the synthesis of ruthenium nanoparticles was developed using microwave irradiation. A colloidal solution of monodispersed anisotropic Ru metal nanoparticles (mean particle size 2-6 nm) with different aspect ratios was obtained first. Particles with different degrees of agglomeration have also been synthesized using monodisperse particles as seeds and PVP (poly-N-vinyl-2-pyrrolidone) as the stabilization reagent. The stabilization mechanisms of different protective reagents were studied by UV-vis spectra. The HRTEM images indicated that dendritic particles formed by controlling agglomeration consisted of single-crystal domains with a random crystalline orientation.     

液化石油气水蒸气重整镍催化剂新型载体研究

以共沉淀法合成了硅铝系载体（AS和SA），并采用改性天然高铝石为原料合成了矿物质载体（MC-1和MC-2）,采用浸渍法合成了镍负载型催化剂。用常压固定床管式反应器，考察了液化石油气水蒸气重整反应活性，通过XRD、物理吸附等手段对催化剂进行了表征。结果表明，以MC-1、MC-2和SA、AS为载体的催化剂的水蒸气重整活性明显高于目前普遍使用的Ni/α-Al2O3催化剂。以SA为载体，负载5%镍的催化剂具有最好的水蒸气重整活性。在750 ℃，水碳比为2.0的条件下转化率达100％，C1选择性达94.46％。XRD分析结果表明1 300 ℃焙烧后的SA载体中存在α-Al2O3晶型和莫来石结构。硅、铝添加次序对水蒸气重整活性影响较大，硅-铝添加次序的催化剂样品的活性高于铝-硅添加次序的样品，C1选择性提高12.7％。     

Coriatone and corianlactone, two novel sesquiterpenes from Coriaria nepalensis

Both coriatone (1). a novel highly oxygenated picrotoxane-type sesquiterpene, and corianlactone (2). with an unprecedented sesquiterpene basic skeleton, named coriane, were isolated from Coriaria nepalensis Wall. The structures of 1 and 2 were determined by analysis of their two-dimensional NMR data, and the structure of 2 was confirmed by X-ray analysis. Compounds 1 and 2 showed no remarkable inhibitory activity toward K(562) cells. They are cytotoxic with IC(50) > 50 microg/mL (cis-platinim: IC(50) = 0.49 microg/mL).     

RE（Ⅲ）—ADP,RE（Ⅲ）—AMP配合物的合成及物性研究

首次合成了具有生物活性的系列配合物RE(Ⅲ)-ADP(稀土-腺苷二磷酸)和RE(Ⅲ)-AMP(稀土-腺苷-磷酸)(RE=Y,La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu),根据红外、紫外、荧光、X射线衍射、元素分析、络合滴定等分析结果,研究了[RE(Ⅲ)(ADP)(H_2O)_3]和[RE(Ⅲ)(AMP)_2(H_2O)_4]H两个系列配合物的化学组成和性质。     

A two-dimensional infrared correlation spectroscopic study on the thermal degradation of poly(2-hydroxyethyl acrylate)-co-methyl methacrylate/SiO2 nanohybrids

Two-dimensional infrared (2D IR) correlation spectroscopy was applied to study the structural changes occurring in the decomposition of PHEA-co-MMA/SiO₂. Complicated absorption spectral changes were observed in the heating process. 2D IR analysis indicates that during heating, covalent bonds, (Si-O-C), between the polymer and the inorganic moiety were formed, which was the main factor in the improvement in thermal properties of the hybrids such as the decomposition temperatures (T_d). The thermal stability of the hybrids was also studied by solid-state ²⁹Si MAS NMR spectroscopy and TGA tests. Their results complemented each other well.     

含有羧基配体的蝎型钒氧配合物的合成、结构及其热分解动力学

设计合成了两种新型的以聚吡唑硼酸盐、氨基酸为配体的钒氧配合物VO[phCH2CH(NH2)COO][HB(pz)3](1)和VO(3,5-Me2pz)[HB(3,5-Me2pz)3](CH3COO)(2). 通过元素分析、红外光谱对配合物进行了表征, 并利用单晶X射线衍射技术解析了它们的结构. 非等温热分解动力学研究表明, 配合物1和2的热分解反应都是分两步进行的. 通过计算, 配合物1热分解的第一步反应的可能机理为成核与生长(n=1/4); 第二步反应的可能机理为化学反应. 其非等温动力学方程分别为, dα/dT=(A/β)e-E/RT(1/4)(1-α)[-ln(1-α)]-3 和dα/dT=(A/β)e-E/RT(1-α)2. 分解反应的表观活化能分别是223.52 和331.94 kJ·mol-1; 指前因子ln(A/s-1)分别是49.67 和57.50. 配合物2 热分解的第一步反应的可能机理为化学反应; 第二步反应的可能机理为成核与生长(n=1/2). 其非等温动力学方程分别为, dα/dT=(A/β)e-E/RT(1-α)2, 和dα/dT=(A/β)e-E/RT(1/2)(1-α)[-ln(1-α)]-1. 分解反应的表观活化能分别是300.56 和444.72 kJ·mol-1; 指前因子ln(A/s-1)分别是75.53 和92.50.     

相转移催化法合成糖苷化合物

糖苷化合物广泛存在于生物体内，中草药和天然药物中的许多抗病活性化合物也是糖苷化合物。根据糖苷化合物分子结构中的配糖体与糖环碳原子相连的原子类型可把糖苷化合物分为氧苷、氮苷、硫苷和碳苷等。未作特殊说明的糖苷化合物均指氧苷，且配糖体为羧酸的糖苷化合物亦称为糖酯。有关糖苷（酯）化合物和其合成方法的研究很多，其中应用相转移催化法较为常见。我们曾用相转移催化法合成过许多糖酯化合物并对其生理活性进行研究报道。本文在原合成糖酯的基础上通过相转移催化法，选用不同于文献报道催化剂及溶剂体系，     

Recent progress in two-photon small molecule fluorescent probes for enzymes

This review aims to provide a summary of the progress in TP small molecule fluorescent probes for enzymes in recent years and displays the main fluorescent mechanisms that have been applied to design probes.     

四苯基卟啉在改性磷酸锆层间的插入及荧光增强

近年来,出于节约一次性能源的考虑,人们已经加大对太阳能等天然资源的利用,致力于模拟天然光合作用的研究[1￣3],而光合作用中的捕光复合物又称为光子天线。光子天线中往往存在一种或几种猝灭剂,猝灭剂吸收光子后产生激发态的能量可以在不同分子或者同一分子的不同生色团之间转移,转移出能量的一方为能量给体,另一方为能量受体。