对三氟甲基偶氮氯膦的合成及其稀土络合物分光光度法的研究——铝合金中稀土总量的测定

合成了新的稀土显色剂对三氟甲基偶氮氯膦。研究了用此显色刑测定铝合金中稀土总量的分光光度法。在酸性介质中与稀土元素成正序反应。轻稀土λ_(max)=668nm,ε=0.96～1.02×10~5·L·mol~(-1)·cm~(-1);重稀土λ_(max)=659nm,ε=1.03～1.29×10~5L·mol~(-1)·cm~(-1)。     

在二甲基亚砜-丙酮-水溶液中硫氰酸钼(Ⅴ)络合物的研究

本文采用分配法研究了二甲基亚砜-丙酮-水溶液中硫氰酸钼(V)络合物的性质。三个络合物MoO(SCN)~(2+),MoO(SCN)_2~+和MoO(SCN)_3的稳定常数分别为β_1=46.1,β_2=1040,β_3=12259,其各级络合物的摩尔吸光系数分别是△ε_1=0.59×10~4L·mol~(-1)·cm~(-1),△ε_2=0.94×10~4L·mol~(-1)·cm~(-1)和△ε_3=1.4×10~4L·mol~(-1)·cm~(-1),研究了该络合物的生成机理,发现以CCI_4,为萃取剂效果不好,如在CCI_4中加入少量溴化十六烷基三甲基铵后萃取效果与前人使用CHCI_3相类似。     

新显色剂偶氮8-羟基喹啉苯基荧光酮的研究与应用——Ⅱ.分光光度法测定镓

2,6,7-三羟基-9-[4-(8-羟基-5-喹啉偶氮基)苯基]荧光酮是一种新的显色剂。该试剂在微碱性溶液中为橙黄色,有CTMAB和F~-存在下与镓形成四元紫红色络合物。络合物λ_(max)=568nm,表观摩尔吸光系数ε′_(568)=2.23×10~5L·mol~(-1)·cm~(-1),用双波长倍增法测得ε′_(568-496)=3.21×10~5L·mol~(-1)·cm~(-1),比单波长法灵敏度提高约44％。用拟定的方法,进行地质样品中痕量镓的测定,得到令人满意的结果。     

聚乙烯醇存在下锇(Ⅱ)-氯化亚锡-结晶紫体系超高灵敏显色反应的研究

本文研究了聚乙烯醇存在下锇(Ⅱ)-氯化亚锡-结晶紫体系的超高灵敏显色反应。反应物λ_(max)=555nm,ε_(555)=1.52×10~6L·mol~(-1)·cm~(-1)。锇含量为(0～4.8)μg/25ml时符合比尔定律。对共存离子的干扰和分离进行了实验,拟定的方法可用于矿石和一些含低品位锇物料的分析。     

钯的PAR-氯化四苯鉮的萃取光度法测定

本文报道了钯与4-(2-吡啶偶氮)间苯二酚(PAR=H_2R,下同)和四苯钟离子形成离子缔合物的化学条件,经氯仿萃取后,建立了一种测定微量钯的萃取光度法。萃取的最佳pH为4.4,络合物的化学式为[(C_6H_5)_4As~+,PdClR~-],其最大吸收峰波长为532nm,表观摩尔吸光系数e_(532)=3.3×10~4L·mol~(-1)·cm~(-1),10mL萃取液中钯量在0～25μg内遵守比耳定律。方法简便,选择性好,用于催化剂中钯的测定,结果满意。     

钍(Ⅳ)与偶氮溴膦-mB和溴化十四烷基吡啶在乙醇-水溶液中的显色反应及其分析应用

在pH1～2的酸性介质中,钍(Ⅳ)与偶氮溴膦-mB(BPAmB)形成最大吸收波长(λ_(max)位于686nm的蓝色络合物,摩尔吸光系数(ε)为8.27×10~4L·mol~(-1)·cm~(-1).在有少量乙醇存在的0.5～1.0 mol/L盐酸溶液中,钍(Ⅳ)能与BPAmB和溴化十四烷基吡啶形成更灵敏的三元络合物,最大吸收位于695nm,具有更大的对比度(△λ=135nm)和更高的灵敏度.ε值达1.41×10~5L·mol~(-1)·cm~(-1),是目前光度法测定钍(Ⅳ)灵敏度最高的显色反应之一,Th(Ⅳ)的浓度在0～800μg/L范围内遵守比尔定律.方法具有良好的选择性,此法用于岩矿中微量钍的测定,结果满意.     

夜蓝与阴离子表面活性剂在水溶液中显色反应——吸光光度法测定环境水样中阴离子表面活性剂

在聚乙烯醇存在的1.8mol/L磷酸溶液中,夜蓝与阴离子表面活性剂形成离子缔合物。溶液由绿色变为蓝色,可用于水相直接光度测定阴离子表面活性剂。最大吸收波长555nm,摩尔吸光系数分别为5.72×10~4L·mol~(-1)·cm~(-1)(十二烷基苯磺酸钠),5.77×10~4 L·mol~(-1)·cm~(-1)(十二烷基硫酸钠),4.36×10~4 L·mol~(-1)·cm~(-1)(十二烷基磺酸钠)。方法简便、快速,具有良好的选择性。可用于河水和生活废水中10~(-6)—10~(-7)mol/L阴离子表面活性剂的测定。     

荷移反应及其在分析化学中的应用 Ⅲ.氟哌酸测定方法研究

本文研究了氟哌酸与四氯对苯醌的荷移反应,确定了反应条件:在硼砂缓冲溶液中形成1:1的络合物,其λ_(max)=375.2nm,表观摩尔吸光系数ε=1.68×10~4·L·mol~(-1)·cm~(-1),应用拟定的方法测定药物制剂含量与文献方法一致,回收率在99％以上,相对标准偏差为1.14％。     

阳离子型微乳液对锰(Ⅱ)-水杨基荧光酮的增敏作用

以阳离子型O/WCTMAB/n-C_5H_(11)OH/n-C_7H_(18)/H_2O微乳液为介质,进行Mn(Ⅱ)-SAF的光度法测定,ε_(575)=1.73×10~5L·mol~(-1)·cm~(-1),与以水为介质ε_(580)=6.59×10~4L·mol~(-1)·cm~(-1)及相同含量CTMABO/W胶束溶液为介质ε_(575)=1.20×10~5L·mol~(-1)·cm~(-1)比较,测定灵敏度显著增加,某些实验条件更为宽容,样品分析结果令人满意。     

溴金酸-罗丹明B和氯金酸-罗丹明6G超高灵敏显色反应的研究——离心光度法测定金

本文研究了一个超高灵敏的测定金的方法,离心光度法。在Au-Br-RB体系中络合物λ_(max)=559nm,表观摩尔吸光系数ε_(559)=3.39×10~(11)L·mol~(-1)·cm~(-1),Au(Ⅲ)浓度(0.20×10~(-5)～2.5×10~(-5)μg/10 ml呈线性关系;Au-Cl-R6G体系络合物λ_(max)=531 nm,表观摩尔吸光系数ε_(531)=2.52×10~8L·mol~(-1)·cm~(-1),Au(Ⅲ)浓度(0.20×10~(-2)～2.4×10μg/10ml。呈线性(Ⅲ)关系。本法已用于某些低品位矿样中金的分析,分析结果与标准值相吻合。探讨了超高灵敏的显色反应机理。     

多环芳二酐型聚酯亚胺膜的透气性能

多环芳二酐型聚酯亚胺膜的透气性能李悦生，丁孟贤，徐纪平（浙江大学高分子科学与工程研究所，杭州，３１００２７）（中国科学院长春应用化学研究所）关键词聚醚酰亚胺，聚酯酰亚胺，膜，透气性通常的聚酰亚胺加工性能较差，在芳环二酐的苯环间引入醚键等柔性基团后，其...     

微量元素与疾病诊断治疗的研究现状及展望

对国内外微量元素与疾病的关系及其诊断治疗的研究现状及研究动向进行了综述，包括：微量元素与地方病、癌肿、心血管病、糖尿病、眼病、神经系统病等。参考文献72篇。     

Determination and study on residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil

A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg^?1, the maximum residue level of European Union for quizalofop-p-ethyl).     

Ti-V基储氢合金及其氢化物的物相结构与组分优化设计

Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB₅型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。     

钒与糖代谢及糖尿病

微量元素钒作为生物体内必需元素，经证实有很重要的生理学功能，与机体糖代谢有十分密切的关系，且能降低糖尿病动物模型的高血糖，极有可能被开发为治疗糖尿病的药物。     

Synthesis of Tyrosol and Hydroxytyrosol Glycofuranosides and Their Biochemical and Biological Activities in Cell-Free and Cellular Assays

Tyrosol (T) and hydroxytyrosol (HOT) and their glycosides are promising candidates for applications in functional food products or in complementary therapy. A series of phenylethanoid glycofuranosides (PEGFs) were synthesized to compare some of their biochemical and biological activities with T and HOT. The optimization of glycosylation promoted by environmentally benign basic zinc carbonate was performed to prepare HOT α-L-arabino-, β-D-apio-, and β-D-ribofuranosides. T and HOT β-D-fructofuranosides, prepared by enzymatic transfructosylation of T and HOT, were also included in the comparative study. The antioxidant capacity and DNA-protective potential of T, HOT, and PEGFs on plasmid DNA were determined using cell-free assays. The DNA-damaging potential of the studied compounds for human hepatoma HepG2 cells and their DNA-protective potential on HepG2 cells against hydrogen peroxide were evaluated using the comet assay. Experiments revealed a spectrum of different activities of the studied compounds. HOT and HOT β-D-fructofuranoside appear to be the best-performing scavengers and protectants of plasmid DNA and HepG2 cells. T and T β-D-fructofuranoside display almost zero or low scavenging/antioxidant activity and protective effects on plasmid DNA or HepG2 cells. The results imply that especially HOT β-D-fructofuranoside and β-D-apiofuranoside could be considered as prospective molecules for the subsequent design of supplements with potential in food and health protection.     

Conformations and steric and stacking interactions of trisubstituted ureas and thioureas with alkyl and phenyl groups

The monomeric ν(N—H) vibrations of various trisubstituted ureas of the R₂UPh type and -thioureas of the R₂TUPh type have been studied. The trans—out isomerism in the former and the trans—out—cis isomerism in the latter are discussed from the point of view of steric effect. The monomeric ν(N—H) vibrations of RPhUPh and RPhTUPh are also examined. The single band appearing in the spectrum of both ureas is characteristic of the cis form; this suggests the existence of phenyl—phenyl interaction (the stacking interaction proposed by Galabov et al. [10]). Behavior of ν(N—H) vibrations at several concentrations is shown to be clearly different in the three forms (trans, out and cis). The presence of the cis form is confirmed by solvent effect experiments.     

Ferrocene and ferrocenium modified clays and their styrene and EVA composites

In this work, ferrocene- and ferrocenium-containing salts were employed to modify montmorillonite. X-ray measurements show an increase in the interlayer spacing upon clay modification, which means that the larger and more organophilic cations were inserted into the gallery space of montmorillonite. Attempts to prepare nanocomposites of polystyrene and ethylene vinyl acetate copolymers lead to immiscible systems; the morphology of these systems was elucidated with TEM, XRD and cone calorimetry. The thermal stability of the composites is greater than that of the virgin polymer.     

Synthesis and Optical and Redox Properties of Symmetric and Asymmetric BODIPYs

Herein, we present the synthetic route and the photophysical, electrochemical as well as laser properties of novel red‐emitting boron‐dipyrromethenes (BODIPYs) bearing arylethyne moieties. Such functionality is added along the main axis of the chromophore leading to single‐ and double‐substituted derivatives. The relationship between the dye structure and the lasing properties is studied in detail with the help of the photophysical and electrochemical properties as well as quantum mechanical simulations. The asymmetric substitution of the parent dye induces inhomogeneities in the charge distribution, which leads to an overall loss of the fluorescence capacity, mainly in polar media. Such non‐radiative deactivation processes can be softened by decreasing the electron‐donor ability of the substituent or even avoided by symmetrical substitution. Thus, grafting of the arylethyne moieties at the longitudinal axis of the indacene core results in an effective strategy to develop red‐edge BODIPYs with highly efficient and photostable laser emission.