显色剂N-辛基-N′-(氨基对苯磺酸钠)硫脲的合成及与金(Ⅲ)的显色反应

介绍了新试剂N-辛基-N′-(氨基对苯磺酸钠)硫脲(OPT)的合成.通过红外光谱、紫外光谱和元素分析等方法测试,确定了该试剂的组成和结构,并研究了该试剂与金(Ⅲ)的显色反应,建立了光度法测定微量金(Ⅲ)的新方法.在pH4.2～5.6的HAc-NaAc缓冲溶液体系中,金(Ⅲ)和OPT形成一种稳定的1:2的水溶性络合物,其最大吸收峰位于302.4nm处,表观摩尔吸光系为1.87×10~5L·mol~(-1)·cm~(-1).Au~(3+)量在8.0～400μg/L服从比尔定律,相关系数r=0.9998.将该法应用于金矿石中微量金的测定,获得满意的结果.     

新显色剂N-对甲苯基-N′-(氨基对苯磺酸钠)硫脲的合成及与金(Ⅲ)显色反应的研究和应用

介绍了新试剂N-对甲苯基-N'-(氨基对苯磺酸钠)硫脲(PMPT)的合成。经过红外、紫外、核磁共振和元素分析等方法测试, 确定了其组成和结构。并研究了试剂与金(Ⅲ)的显色反应, 建立了光度法测定微量金(Ⅲ)的新方法。 在pH3.2～5.8的HAc～NaAc缓冲体系中, 该试剂和金(Ⅲ)形成一种稳定的组成比为1∶2的水溶性配合物,配合物的最大吸收峰位于312.6nm处,表观摩尔吸光系数为2.54×10     

新试剂N-苯基-N′-(氨基对苯磺酸钠)硫脲的合成及其在微量金(Ⅲ)测定中的应用

介绍了新试剂N 苯基 N′ (氨基对苯磺酸钠 )硫脲 (PPT)的合成方法。并研究了与金的显色条件 ,建立了光度法测定微量金的新方法。在pH 5 .0～ 5 8的HAc NaAc缓冲体系中 ,在溴化十六烷基三甲胺 (CTMAB)存在下 ,Au(Ⅲ )与PPT形成组成比 1∶3的黄色水溶性络合物 ,其最大吸收峰位于 31 7.0nm ,表观摩尔吸光系数ε=3.68× 1 0 4 L/mol·cm ,Au(Ⅲ )含量在 0～ 80 μg/2 5mL范围内服从比尔定律。     

N-对甲苯基-N''''-(氨基对苯磺酸钠)硫脲的合成及与铂(Ⅳ)的显色反应

详细介绍了新试剂N-对甲苯基-N’-(氨基对苯磺酸钠)硫脲(PMPT)的合成.经过红外光谱、紫外光谱、核磁共振和元素分析等方法测试,确定了试剂的组成和结构.研究了试剂与铂(Ⅳ)的显色反应,建立了光度法测定微量铂(Ⅳ)的方法.在pH3.6～5.2的HAc-NaAc缓冲体系中,该试剂和铂(Ⅳ)-形成一种稳定的组成比为1:3的绿色水溶性络合物,其最大吸收峰位于756nm处,表观摩尔吸光系数为ε_(756)=1.14×10~5·L·mol~(-1)·cm~(-1).铂含量在4～336μg/L服从比尔定律,相关系数r=0.9997,近50种离子不干扰.将该法应用于矿石和催化剂中铂的测定,获得满意的结果.     

新显色剂8-[杯(4)芳烃偶氮]氨基喹啉的合成及其与金的显色反应

合成了一种新的杂环偶氮类显色试剂 8 [杯 ( 4 )芳烃偶氮 ]氨基喹啉(CAQ) 1。研究了该试剂与金的显色反应的适宜条件 ,在碱性介质中 ,在CTMAB存在下 ,试剂与金生成 1∶1稳定络合物 ,建立了测定金的光度法新体系 ,体系至少可稳定 8h ,λmax =640nm ,ε =2 .0 6× 1 0 5L·mol-1·cm-1,金含量在 0～ 2 2μg 2 5mL内符合比尔定律。方法已用于金矿石中微量金的测定。     

meso-四(N-甲基-3-吡啶基)卟啉与金(Ⅲ)反应的分光光度研究

本文制定了以meso-四(N-甲基-3-吡啶基)卟啉〔T(3-MPy)P〕测定微量金(Ⅲ)的分光光度法,研究了金(Ⅲ)与T(3-MPy)P反应的动力学性质,测定了该反应的速率常数及活化能。金(Ⅲ)与T(3-MPy)P形成2:1的配合物,其表观摩尔吸光系数为3.24×10~5L·mol~(-1)·cm~(-1)。     

新试剂(2,6-二氯-4-硝基苯)-3-(4-硝基苯)-三氮烯的合成及其与汞的显色反应研究

合成了新试剂(2,6-二氯-4-硝基苯)-3-(4-硝基苯)-三氮烯(DCNPNPT),测定了试剂的亚氨基离解常数pKa＝9．2。在TritonX-100存在下,pH9．8～11．0范围内,试剂与Hg2+形成14黄色型配合物,用双波长法测得其表观摩尔吸光系数为2．27×105L·mol-1·cm-1。汞含量在0～10μg／25ml范围内符合比耳定律,用此法测定了天然水和实验室废水中微量汞含量,结果满意。     

金(Ⅲ)与 3,3’,5,5’-四甲基联苯胺显色反应的研究和应用于微量金的测定

本文研究了An(Ⅲ)与 3,3′,5.5′-四甲基联苯胺(TMB)的显色反应,在0.02mol/L盐酸介质中,TMB于波长450nm处有最大吸收,摩尔吸光系数为1.03×10~5L·mol~(-1).cm~(-1).25ml溶液中0～40μg金(Ⅲ)符合比尔定律,本方法已用于粗铜中微量金的测定.     

锑(Ⅲ)-钛铁试剂-溴化十六烷基三甲胺体系极谱络合吸附波研究

在 0 .0 4mol·L- 1磷酸中 ,锑 (Ⅲ ) 钛铁试剂 (Tiron) 溴化十六烷基三甲胺体系产生灵敏的极谱络合吸附波。峰电位为 - 0 .4 4V(vs .SCE) ,二阶导数峰高与锑 (Ⅲ )浓度在 8.2× 10 - 10 ～ 2 .0× 10 - 6mol·L- 1范围内呈线性关系 ,检出限达 4× 10 - 10 mol·L- 1。研究了极谱波的性质及电极反应机理。方法应用于三氧化二砷及铜合金中微量锑的直接测定 ,结果满意     

催化光度法测定痕量Mn(Ⅱ)的研究——Mn(Ⅱ)-铍试剂Ⅲ-H_2O_2体系

研究了0.10mol·L~(-1)氨水介质中,Mn(Ⅱ)催化H_2O_2氧化铍试剂Ⅲ退色的反应,选择了最佳反应条件下。方法的检出限为2.0×10~(-10)g·ml~(-1),线性范围为0.4～20.0ng·ml~(-1)。本法简单灵敏、选择性较好,可直接测定茶叶中Mn(Ⅱ)含量。     

OH(3) (-) and O(2)H(5) (-) double Rydberg anions: predictions and comparisons with NH(4) (-) and N(2)H(7) (-)

A low barrier in the reaction pathway between the double Rydberg isomer of OH(3) (-) and a hydride-water complex indicates that the former species is more difficult to isolate and characterize through anion photoelectron spectroscopy than the well known double Rydberg anion (DRA), tetrahedral NH(4) (-). Electron propagator calculations of vertical electron detachment energies (VEDEs) and isosurface plots of the electron localization function disclose that the transition state's electronic structure more closely resembles that of the DRA than that of the hydride-water complex. Possible stabilization of the OH(3) (-) DRA through hydrogen bonding or ion-dipole interactions is examined through calculations on O(2)H(5) (-) species. Three O(2)H(5) (-) minima with H(-)(H(2)O)(2), hydrogen-bridged, and DRA-molecule structures resemble previously discovered N(2)H(7) (-) species and have well separated VEDEs that may be observable in anion photoelectron spectra.     

Mixed ligand titanium(IV) complexes. Chlorobis(dithiocarbamato)bis(methylsalicylato)titanium(IV) andbis(dithiocarbamato)bis(methylsalicylato)titanium(IV)

Summary Dichlorobis(methylsalicylato)titanium(IV) reacts with potassium or amine salts of dialkyl or diaryl dithiocarbamates in 11 and 12 molar ratios in anhydrous benzene (room temperature) or in boiling CH₂Cl₂ to yield mixed ligand complexes: (AcOC₆H₄O)₂ Ti(S₂CNR₂)Cl (1) and (AcOC₆H₄O)₂ Ti(S₂CNR₂)₂ (2), R=Et, n-Pr, n-Bu, cyclo-C₄H₈ and cyclo-C₅H₁₀. These compounds are moisture sensitive and highly soluble in polar solvents. Molecular weight measurement in conjunction with i.r.,¹H and¹³C n.m.r. spectral studies suggest coordination number 7 and 8 around titanium(IV) in (1) and (2) respectively.     

Bis(trifluoroacetyl) peroxide, CF(3)C(O)OOC(O)CF(3)

Pure, highly explosive CF(3)C(O)OOC(O)CF(3) is prepared for the first time by low-temperature reaction between CF(3)C(O)Cl and Na(2)O(2). At room temperature CF(3)C(O)OOC(O)CF(3) is stable for days in the liquid or gaseous state. The melting point is -37.5 degrees C, and the boiling point is extrapolated to 44 degrees C from the vapor pressure curve log p = -1875/T + 8.92 (p/mbar, T/K). Above room temperature the first-order unimolecular decay into C(2)F(6) + CO(2) occurs with an activation energy of 129 kJ mol(-1). CF(3)C(O)OOC(O)CF(3) is a clean source for CF(3) radicals as demonstrated by matrix-isolation experiments. The pure compound is characterized by NMR, vibrational, and UV spectroscopy. The geometric structure is determined by gas electron diffraction and quantum chemical calculations (HF, B3PW91, B3LYP, and MP2 with 6-31G basis sets). The molecule possesses syn-syn conformation (both C=O bonds synperiplanar to the O-O bond) with O-O = 1.426(10) A and dihedral angle phi(C-O-O-C) = 86.5(32) degrees. The density functional calculations reproduce the experimental structure very well.     

Syntheses and structures of the infinite chain compounds Cs(4)Ti(3)Se(13), Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14)

The alkali metal/group 4 metal/polychalcogenides Cs(4)Ti(3)Se(13), Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14) have been synthesized by means of the reactive flux method at 823 or 873 K. Cs(4)Ti(3)Se(13) crystallizes in a new structure type in space group C(2)(2)-P2(1) with eight formula units in a monoclinic cell at T = 153 K of dimensions a = 10.2524(6) A, b = 32.468(2) A, c = 14.6747(8) A, beta = 100.008(1) degrees. Cs(4)Ti(3)Se(13) is composed of four independent one-dimensional [Ti(3)Se(13)(4-)] chains separated by Cs(+) cations. These chains adopt hexagonal closest packing along the [100] direction. The [Ti(3)Se(13)(4-)] chains are built from the face- and edge-sharing of pentagonal pyramids and pentagonal bipyramids. Formal oxidation states cannot be assigned in Cs(4)Ti(3)Se(13). The compounds Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14) crystallize in the K(4)Ti(3)S(14) structure type with four formula units in space group C(2)(h)()(6)-C2/c of the monoclinic system at T = 153 K in cells of dimensions a = 21.085(1) A, b = 8.1169(5) A, c = 13.1992(8) A, beta = 112.835(1) degrees for Rb(4)Ti(3)S(14);a = 21.329(3) A, b = 8.415(1) A, c = 13.678(2) A, beta = 113.801(2) degrees for Cs(4)Ti(3)S(14); a = 21.643(2) A, b = 8.1848(8) A, c = 13.331(1) A, beta = 111.762(2) degrees for Rb(4)Hf(3)S(14); a = 22.605(7) A, b = 8.552(3) A, c = 13.880(4) A, beta = 110.919(9) degrees for Rb(4)Zr(3)Se(14); a = 22.826(5) A, b = 8.841(2) A, c = 14.278(3) A, beta = 111.456(4) degrees for Cs(4)Zr(3)Se(14); and a = 22.758(5) A, b = 8.844(2) A, c = 14.276(3) A, beta = 111.88(3) degrees for Cs(4)Hf(3)Se(14). These A(4)M(3)Q(14) compounds (A = alkali metal; M = group 4 metal; Q = chalcogen) contain hexagonally closest-packed [M(3)Q(14)(4-)] chains that run in the [101] direction and are separated by A(+) cations. Each [M(3)Q(14)(4-)] chain is built from a [M(3)Q(14)] unit that consists of two MQ(7) pentagonal bipyramids or one distorted MQ(8) bicapped octahedron bonded together by edge- or face-sharing. Each [M(3)Q(14)] unit contains six Q(2)(2-) dimers, with Q-Q distances in the normal single-bond range 2.0616(9)-2.095(2) A for S-S and 2.367(1)-2.391(2) A for Se-Se. The A(4)M(3)Q(14) compounds can be formulated as (A(+))(4)(M(4+))(3)(Q(2)(2-))(6)(Q(2-))(2).