微乳液在光度分析中的应用

文中对微乳液的特性与分类,及其在吸光光度分析中的应用及增敏作用机理作了评述。     

碳铂类似物的合成,表征及对大鼠W—256肉瘤的抑制作用

合成了十八种〔PtA_2X〕·yH_2O,其中A分别为NH_3、CH_3NH_2、1/2乙二胺和1/2(2,3-二甲基-2,3-丁二胺),X分别为1,1-环丙烷二羧酸根(CPrDCA)、2-甲-1,1-环丙烷二羧酸根(2-M-CPrDCA)、2-甲-1,1-环丁烷二羧酸根(2-M-CBDCA)、1,2-环戊烷二羧酸根(CPDCA)和1,1-环已烷二羧酸根(CHDCA),并进行了表征。测定了配合物抑制大鼠W-256肉瘤的活性,发现配合物〔Pt(NH_3)_2X〕系列按X不同有以下的活性次序:CPrDCA>2-M-CPrDCA>CPDCA>CBDCA(碳铂)≥2-M-CBDCA。     

在增溶剂存在下硫氰酸盐-结晶紫光度法测定微量钨

在明胶存在下,钨与硫氰酸盐和结晶紫生成可溶性三元缔合物,最大吸收波长为540nm,表现摩尔吸光系数为4.1×10~5 L·mol~(-1)·cm~(-1),钨在0～11μg/25ml范围内服从比尔定律。方法已用于测定岩石中微量钨。     

配位聚合载体化催化剂ESR研究进展

本文概述了配位聚合载体化催化剂的ESR研究进展,介绍了载体研究、活性中心研究及计算机模拟技术研究方面的发展概况.     

A novel gel polymer electrolyte based on poly ionic liquid 1-ethyl 3-(2-methacryloyloxy ethyl) imidazolium iodide

Poly ionic liquid 1-ethyl 3-(2-methacryloyloxy ethyl) imidazolium iodide (PEMEImI) as a single-ion conductor was designed and synthesized. When appropriate amount of suitable plasticizers, I₂ and polyacrylonitrile (PAN) were incorporated into it, the complex formed gel polymer electrolyte. Chemical structure, thermal behavior and ionic conductive properties of the gel polymer electrolyte were investigated by Raman spectra, UV-Vis spectra, differential scanning calorimetry (DSC), and complex impedance analysis, respectively. For the new gel polymer electrolyte, the ionic conductivity of about 1 × 10⁻³ S cm⁻¹ at room temperature was achieved.     

纳米二氧化钛分离/富集-石墨原子吸收光谱法测定环境样品中痕量镉

以石墨炉原子吸收(GFAAS)为检测手段,研究了纳米二氧化钛(TiO2,锐钛型)对金属Cd(Ⅱ)的吸附性能,考察了吸附和解吸的主要影响因素.结果表明,在较宽的pH范围内,纳米TiO2对Cd(Ⅱ)具有良好的吸附性能,3.0 mol/L HCl能将所吸附的Cd(Ⅱ)完全洗脱.在优化的实验条件下,具有吸附容量大、吸附速度快的特点.本法的检出限(3σ)为10.6 ng/L;相对标准偏差(RSD)为1.5%,(n=7,C=2.0 μg/L),富集50倍.本法测定标准样品的测定值与参考值吻合.用于土壤类样品中Cd(Ⅱ)的测定,结果令人满意.     

Effect of a novel phosphorous-nitrogen containing intumescent flame retardant on the fire retardancy and the thermal behaviour of poly(butylene terephthalate)

A novel phosphorus-nitrogen containing intumescent flame retardant (P-N IFR) was prepared via the reaction of a caged bicyclic phosphorus (PEPA) compound and 4,4′-diamino diphenyl methane (DDM) in two steps. The product was added to poly(butylene terephthalate) (PBT) to obtain halogen-free flame retarded polyester. UL-94 test, thermogravimetry and in situ infrared spectroscopy were used to characterize the flammability, thermal degradation properties and the char-forming process. It was shown that the phosphorus-nitrogen containing compound could improve both the flame retardancy and thermal stability more effectively than other P-N flame retardants. Furthermore, it was a good char-forming agent incorporated with the co-addition of polyurethane (PU) when the combustion occurred. The formation of P-N structure was incorporated in the char layer.     

Preparation and characterization of nitrogen-doped TiO2 photocatalyst in different acid environments

Nitrogen-doped TiO₂ powders were successfully prepared by a wet method, i.e., a micro-emulsion-hydrothermal method, in different acid environments. Several characterization techniques, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV-visible diffuse reflectance spectra, were combined to determine the crystal phase, concentration and chemical states of the nitrogen doped in TiO₂. The high photocatalytic activity of the nitrogen-doped TiO₂ was evaluated through the decomposition of rhodanmine B under visible light irradiation. It was suggested that the doped nitrogen formed oxynitride (NO) and produced impurity states at higher above the valence band of TiO₂. Therefore, the nitrogen doping could enhance the response of photocatalyst to the visible light and improve the photocatalytic activity because of the narrowing of band gap of TiO₂.