树脂吸附法处理3,6-二氯水杨酸生产废水

研究了树脂吸附法处理3,6-二氯水杨酸生产废水的工艺过程。结果表明,NDA-77吸附树脂对该废水具有良好的吸附-脱附效果。经树脂吸附处理,废水中主要有机污染物2,5-二氯苯酚和3,6-二氯水杨酸均得到去除,总有机碳(TOC)由210mg/L降为20mg/L以下,吸附饱和的树脂可采用稀碱液实现完全再生。经吸附处理去除有机物后,废水中含有20%的KCl,可进入工厂现有的KCl隔膜电解装置,用于KOH的生产。     

Homogeneous rare earth coordination catalysts for copolymerization of styrene with acrylonitrile

The study on homogeneous rare earth coordination catalysts, LnL₃-Al(i-Bu)₃-CCl₄, for the copolymerization of styrene with acrylonitrile has been successfully carried out for the first time. Some features and kinetic behavior of copolymerization of styrene with acrylonitrile by Nd(P₂₀₄)₃-Al(i-Bu)₃-CCl₄ system are described. The catalyst sites appear to possess both coordinate anionic and free radical characteristics. The catalytic activity of various rare earth elements in Ln(P₂₀₄)₃ and ligands in NdL₃ for the copolymerization have the following order, respectively: Yb > Er > Tb ～ Tm > Ho > Ce > Lu ～ Sm ～ La > Pr > Nd, and Nd(naph)₃ > Nd(P₂₀₄)₃ ～ Nd(P₅₀₇)₃ > Nd(acac)₃·3H₂O. An alternating-rich copolymer of styrene-acrylonitrile with a high softening point (195–230°C) was obtained by the LnL₃-Al(i-Bu)₃-CCl₄ systems in toluene at 80°C.     

Theoretical study of nitric oxide adsorption on Au clusters

The adsorption properties of NO molecule on anionic, cationic, and neutral Au(n) clusters (n=1-6) are studied using the density functional theory with the generalized gradient approximation, and with the hybrid functional. For anionic and cationic clusters, the charge transfer between the Au clusters and NO molecule and the corresponding weakening and elongation of the N-O bond are essential factors of the adsorption. The neutral Au clusters have also remarkable adsorption ability to NO molecule. The adsorption energies of NO on the cationic clusters are generally greater than those on the neutral and anionic clusters.     

Application of L-Cysteine-Capped ZnS Nanoparticles in the Determination of Nucleic Acids Using the Resonance Light Scattering Method

Nanometer-sized L-cysteine-capped ZnS particles were synthesized by a colloidal aqueous method. The functionalized nanoparticles are water-soluble and suitable for biological applications. In Tris-HCl buffer solution, nucleic acids combine with cysteine-capped nano-ZnS particles by intermolecular forces to form larger nanoparticles. There are two resonance light scattering peaks at 304.5nm and 373.8nm, respectively. The enhanced RLS is related to the concentration of nucleic acids in the range of 0.04 to 1.2µgmL^–1 for calf thymus DNA and 0.2 to 1.0µgmL^–1 for fish sperm DNA. The detection limits (3) are 19ngmL^–1 for calf thymus DNA and 23ngmL^–1 for fish sperm DNA, respectively. Four synthetic samples were analyzed satisfactorily.     

可见光照射下丙炔光催化水解反应的研究 Ⅱ．钒离子对二氧化钛催化性能的影响

 研究了几种不同粒径的TiO2在CH3CCH和H2O的光催化反应中的催化活性．结果表明,利用离子注入法可以拓展纳米TiO2催化剂的光吸收区域,使其吸收带向可见光方向偏移,且偏移程度随着TiO2粒径的增大而增大;特别是注入V离子使TiO2催化剂在可见光区域具有光催化活性．V离子注入后,TiO2催化剂在紫外区域的光催化活性没有下降,但在可见光区域的光催化活性有所提高．在五种光催化剂中,具有中等粒径大小的P－25注入V离子后表现出最高的光催化活性．在太阳光直接照射下,这些光催化剂也具有较高的催化活性．     

A first-principles study of (R)- and (S)-PPA Molecules on Cu(111)

The adsorption of (R)- and (S)-2-phenylpropionamide (PPA, C(9)H(11)ON) molecules on a Cu(111) surface has been investigated using the density functional method with supercell models. The adsorption orientations of both (R)- and (S)-PPA molecules on the surface are the same: the phenyl rings are approximately parallel to the Cu(111) surface and positioned in the hollow sites, the amino and methyl groups occupy two-bridge sites, and the carbonyl occupies the top site. After the adsorption, the bond lengths in the two enantiomers are almost unchanged, but the changes for two dihedral angles show differences, especially for (R)-PPA molecule. The first angles between the (N,C9,C7) plane and the (C9,C7,C6) plane are 19.4 and 0.7 degrees for (R)- and (S)-PPA molecules, respectively, and the second angles between the (C8,C7,C6) plane and the (C7,C6,C5) plane are 74.8 and 0.4 degrees for (R)- and (S)-PPA molecules, respectively. The adsorption energies of (R)- and (S)-PPA molecules are calculated to be -34 and -26 kJ mol(-1), respectively. The simulated scanning tunneling microscopy (STM) images of (R)- and (S)-PPA molecules on the Cu(111) surface display different features and are coincident with the experimental ones. The interaction between the adsorption molecule and the metal surface is found to be responsible for the discrimination of (R)- and (S)-PPA molecules on the surface.     

REATMENT AND RESOURCE REUSE OF 1,2,4-ACID PRODUCING EFFLUENT WITH MACROPOROUS POLYMERIC ADSORBENT

1. INTRODUCTION 1,2,4-acid (1-Amino-2-naphthol-4-sulfonic acid) is among the most important naphthalene derivatives which are widely used as the intermediates of dyestuffs. In its production process, however, high strength wastewater streams are gene…