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1.
丁基罗丹明B—钼酸盐光度法连续测定铈和钪   总被引:4,自引:0,他引:4  
王加林  徐其亨 《分析化学》1996,24(3):344-347
在聚乙烯醇(PVA)存在下,丁基罗丹明B(BRB)分别与铈钼、钪钼杂多酸络阴离子形成离子缔合物,其最大吸收均位于570nm,表面摩尔吸光度分别为εCe=3.96×10^6L.mol^-1.cm^-1,εSc=4.71×10^5L.mol^-1.cm^-1,服从比耳定律范围分别为0-24μg/L Ce和0-60μg/LSc,测定极限为Ce1.0μg/L(n=12)和Sc1.9μg/L(n=10),对  相似文献   

2.
催化动力学光度法测定痕量苯酚   总被引:5,自引:0,他引:5  
研究了在硫酸介质中苯酚对I^-1催化Ce^4+-As(Ⅲ)反应的抑制作用及其动力学条件。建立了用催化动力这光度法测定痕量苯酚的新方法,结果表明,在0.001mol/LCe(SO4)2,0.00125mol/L,As2O3,0.01mg/L,KI,0.0125mol/L,H2SO4和0.13%(w/v)NaCl溶液中测定苯酚,其表面摩尔吸光系数为2.1×10^5L.mol^-1.cm^-1,线性范围  相似文献   

3.
用钼酸盐和罗丹明B连续光度法测定铈和钪   总被引:4,自引:0,他引:4  
聚乙烯醇存在下,铈或钪钼杂多酸与罗丹明B(RB)形成离子缔合物,最大吸收均位于570nm,摩尔吸光系数分别为1.16×10^6和5.62×10^5L.mol^-1.cm^-1,cm^-1,0-1.2μg/25mLCe和0-2.0μg/mLSc服从比耳定律,检测限1.5ng/mLCe(n=10)和1.1ng/mLSc(n=9)。缔合物的摩尔比为Ce:mO:RB=1:6:3和 Sc:Mo:RB=1:1  相似文献   

4.
马东兰  张雷 《分析化学》1995,23(3):280-283
本报道了极易溶于水的显色剂N-烯丙基-N'-(氨基对苯磺酸钠)硫脲光度法测定钯的条件,:在PH4.0-5.5缓冲介质中,ASATu与钯生成易溶于水的、稳定的黄色络合物,组成比为:Pd(Ⅲ):ASATu=1:4;络合物的最大吸收波长为296.0nm表观摩尔吸光系数ε296=1.33×10^5L.mol^-1.cm^-1;钯(Ⅱ)在0-20嗳μg/25mL呈线性,相关系数γ=0.9995。该法灵敏度  相似文献   

5.
铁的单点络合滴定法研究   总被引:1,自引:0,他引:1  
唐春然  曾云龙 《分析化学》1995,23(9):1043-1046
本研究了Fe^3+的单点络合滴定法,导出了定量关系式,比较了以铂电极为指示电极和以PVC膜四氯络铁(Ⅲ)阴离子电极为指示电极时电位测量的稳定性及所得的分析结果。在Fe^3+浓度为1.000×10^-3mol/L时,18次实验的平均值为1.02×10^-4mol/L,相对偏差小于1.7%;Fe^3+在5.0×10^3mol/L以上时,相对偏差小于0.1%;其浓度小于10^-3mol/L而大于5×1  相似文献   

6.
阿霉素在钴离子注入修饰电极上的电化学行为及其应用   总被引:2,自引:0,他引:2  
胡劲波  支瑶  李启隆 《分析化学》1999,27(11):1280-1283
阿霉素在0.1mol/L HAc-NaAc(pH4.62)缓冲溶液中用注入钴的修饰玻碳电极为工作电极进行伏安测定,得到一良好的还原峰;Ep=-0.522V(vs.SCE)。峰电流与阿霉素浓度在1.4×10^-6-1.4×10^-6mol/L和1.4×10^-6-5.6×10^-5mol/L范围内呈线性关系,。  相似文献   

7.
钯(Ⅱ)与对碘偶氮氯膦显色反应的研究   总被引:11,自引:0,他引:11  
钯(Ⅱ)与对碘偶氮氯膦在硝酸介质中形成组成比为1:2的蓝色配合物,其最大吸收波长位于640nm,表观摩尔吸光系数ε=3.3×10^4L·mol^-1·cm^-1,钯的质量浓度在0.0 ̄1.0mg/L范围内符合比尔定律。应用于废钯催化剂回收液中铯含量的测定,结果满意。  相似文献   

8.
5′—硝基水杨基荧光酮分光光度测定微量碲   总被引:4,自引:0,他引:4  
在pH4.1~4.6乙酸盐缓冲介质中,碲(Ⅳ)与5′硝基水杨基荧光酮(5′-NSF)溴化十六烷基吡啶(CPB)反应形成组成比为1:4;4的水溶性和稳定性皆佳的红色三元配合物,最大吸收波长为542nm,表观摩尔吸光系数为1.02×10^5L.mol^-1.cm^-1,桑德尔灵敏度是1.25×10^-3μg.cm^-2线性范围0~0.40mg/L,据此提出了测定碲的灵敏,简便的分光光度分析新方法,直接  相似文献   

9.
利用717型阴离子交换树脂吸附Fe-硫氰酸盐-吐温80配合物,配合物最大吸收峰位于波长481.4nm,表观摩尔吸光系数为1.06×10^5L.mol^-1.cm^-1,Fe量在0-800μg/L服从比尔定律,建立了相应Fe的固相分光光度法,应用于高纯稀土中痕量铁的测定,结果满意。  相似文献   

10.
刘彬  张光 《分析试验室》1996,15(5):27-29
用新合成的偶氮试剂2-(5-硝基-2-吡啶偶氮)-5-二甲氨基苯胺研究了光度法测定钯的反应条件。结果表明,在0.45-1.2mol/L盐酸介质中,钯与试剂形成稳定的蓝色配合物,其最大吸收波长位于621nm处,表观摩尔吸收系数为9.4×10^4L.mol^-1.cm^-1,配合成的组成为Pd:5-NO2-PADMA=1:2,钯浓度在0-10μg/10mL范围内符合比尔定律。本方法是目前测定钯的高灵敏  相似文献   

11.
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...  相似文献   

12.
13.
微量元素与疾病诊断治疗的研究现状及展望   总被引:8,自引:0,他引:8  
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。  相似文献   

14.
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).  相似文献   

15.
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.  相似文献   

16.
朱劲波  马立群  梁飞  苗迎春  王立民 《应用化学》2015,32(11):1221-1230
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。  相似文献   

17.
钒与糖代谢及糖尿病   总被引:1,自引:0,他引:1  
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。  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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