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1.
2-(2-喹啉偶氮)-5-二乙氨基苯胺光度法测定钴   总被引:12,自引:0,他引:12  
合成了新试剂 2 (2 喹啉偶氮 ) 5 二乙氨基苯胺 (QADEAA) ,并研究了其与钴的显色反应 ,在pH为5 .5的磷酸盐缓冲介质中 ,在CTMAB存在下 ,QADEAA与钴反应生成 2∶1稳定络合物 ;用磷酸酸化后 ,在酸介质中 ,体系λmax=6 2 5nm ,ε =1 .4 6× 1 0 5L·mol-1 ·cm-1 。钴含量在 0 .0 1~ 0 .30mg/L内符合比尔定律。方法用于大米、猪肝及水样中钴含量的测定 ,结果令人满意  相似文献   

2.
研究了 2 (2 喹啉偶氮 ) 5 二甲氨基苯甲酸 (QADMAA)试剂与铜的显色反应 ,在pH 4 .5的HOAc NaOAc缓冲介质中 ,吐温 80存在下 ,QADMAA与铜反应生成 2∶1稳定络合物 ,λmax=5 60nm ,ε =1.32× 10 5L·mol- 1·cm- 1。铜含量在 0~ 8μg/2 5ml内符合比耳定律 ,方法用于铝合金中铜含量的测定 ,结果满意  相似文献   

3.
探讨了新显色剂 1-羟基-2-(5-NO2-2-吡啶偶氮)-8-氨基-3,6-萘二磺酸(简称5-NO2-PAH)与铜离子显色的适宜条件及其共存离子的影响,建立了 5-NO2-PAH测定铜的新显色反应体系.在 pH 7.0~10.0 范围内,铜与试剂形成稳定的 1∶2 配合物,其最大吸收峰位于 653 nm, 表观摩尔吸光系数εCu=4.68×104 L·mol-1·cm-1,铜的浓度在 0 μg/10 mL~14 μg/10 mL 范围内遵守比尔定律.方法已用于合金中铜的测定.  相似文献   

4.
本文研究了2-(6-硝基-2-苯并噻唑偶氮)-5-二甲氨基苯甲酸(6-NO_2-BTAMB)与铜的显色反应。结果表明,在pH2.0~4.5的乙醇水溶液中6-NO_2-BTAMB与铜形成一种稳定的蓝绿色络合物,其最大吸收波长位于650nm处,表观摩尔吸收系数为7.75×10~4L·mol~(-1)·cm~(-1),络合物的组成为6-NO_2·BTAMB:Cu=1:1,铜浓度在0~10μg/10ml范围内服从比尔定律。该方法具有良好的选择性和灵敏度。在氟化铵和硫脲存在下,利用差减法,可直接测定含微量镍和钴的镁、铝合金中的铜,结果满意。  相似文献   

5.
提出用5 (5 硝基 2 吡啶偶氮) 2,4 二氨基甲苯(5 NO2 PADAT)光度法同时测定铜和钯的新体系。室温下,铜与试剂仅能在pH4.5~6.0范围内定量反应,而钯与试剂于强酸性介质中即可显色完全。基于铜配合物可被EDTA分解而钯配合物不被分解,及铜、钯配合物形成的酸度差异,实现了铜、钯的同时测定。铜浓度在0~0.7μg·ml-1、钯浓度在0~0.9μg·ml-1范围内符合比耳定律,其表观摩尔吸光系数分别为ε519Cu=6.70×104L·mol-1·cm-1,ε592Pd=1.25×105L·mol-1·cm-1。方法已成功用于矿样和电镀活化废液中铜、钯的同时测定。  相似文献   

6.
2-(H-酸偶氮)-4,5-二硝基苯酚与钍的显色反应研究及其应用   总被引:1,自引:0,他引:1  
研究了 2 (H 酸偶氮 ) 4 ,5二硝基苯酚 (HADNP)与钍的显色反应 ,在 pH 5 .5HOAc NaOAc缓冲介质中 ,溴化十六烷基吡啶 (CPB)存在下 ,HADNP与钍反应生成 2∶1稳定紫红色络合物 ,λmax=6 2 0nm ,ε =1.2 3× 10 5L·mol- 1·cm- 1。钍含量在 0~ 30 μg/2 5ml内符合比耳定律 ,方法用于环境水样品中钍含量的测定 ,结果满意。  相似文献   

7.
本文研究了α-环糊精存在下,铜与meso-四(4-甲氧基-3-磺酸基苯)卟啉显色反应的条件,其最大吸收在417nm处,摩尔吸光系数为2.5×10~5L·mol~(-1)·cm~(-1)铜含量在0~2μg/10.75ml内符合比尔定律,并利用此法测定了果树叶和头发中的铜。  相似文献   

8.
研究了2 (2 喹啉偶氮) 1,5 苯二酚(QADHB)试剂与银的显色反应,在pH 5.0的柠檬酸氢氧化钠缓冲(内含0. 01 mol·L-1 的Na2EDTA)介质中,十二烷基磺酸钠(SDS)存在下,QADHB与银反应生成2∶1 稳定的络合物,λmax=550 nm,ε=6.56×104L·mol-1·cm-1。银含量在0~30μg/25 mL内符合比耳定律,方法用于环境水样中银含量的测定,结果满意。  相似文献   

9.
合成了新试剂2-(2-喹啉偶氮)-4-甲基-1,3-苯二酚(QAMDHB),并研究了试剂与铜的显色反应,在pH 2.2磷酸-磷酸二氢钾缓冲介质中,溴化十六烷基三甲基胺(CTMAB)存在下,QAMDHB与铜反应生成21稳定络合物,该络合物可被Waters PorapakR Sep-Park-C18固相萃取小柱萃取,用乙醇洗脱后用光度法测定,在乙醇相中λmax=550nm,ε=3.92×104L@mol-1@cm-1.铜含量在0~1.0μg@ml-1范围内符合比耳定律,方法用于环境水样中铜含量的测定,结果满意.  相似文献   

10.
研究了双 (6-氧 -丁烯二酸单酯 ) -β-环糊精 (简称β- CD衍生物 )对 Pd( ) - 2 - (5-溴 - 2 -吡啶偶氮 ) - 5-二乙氨基苯酚 (简称 Pd( ) - 5- Br- PADAP)显色反应的增敏作用。在 p H=4.0~ 5.0的 HAc- Na Ac介质中 ,该体系最大吸收波长为 590 nm,表观摩尔吸光系数为 6.71× 1 0 4 L· mol-1· cm-1,钯 ( )含量在0~ 1 1 μg/1 0 m L范围内服从比尔定律。方法用于活性炭载体催化剂和矿样中钯的测定  相似文献   

11.
A sensitive, selective and rapid method for the determination of nickel based on a rapid reaction of nickel(II) with 2-(2-quinolylazo)-5-diethylaminoaniline (QADEAA) has been developed. In the presence of pH = 6.0 ammonia-ammonium chloride buffer solution and sodium dodecyl sulfonate (SDS) medium, QADEAA reacts with nickel to form a violet complex having a molar ratio of 1:2 (nickel to QADEAA). The molar absorptivity of the complex is 1.38 x 10(5) l mol(-1) cm(-1) at 595 nm. Beer's law is obeyed in the range of 0.01-0.4 microg/ml. This method had been applied to the determination of nickel with good results.  相似文献   

12.
报道了1-(4-硝基苯基)-3-(2-苯并咪唑)-三氮烯(NPBMT)的合成及其与铜(Ⅱ)的显色反应。在非离子表面活性剂OP存在下,于pH11.5的Na2B4O7-NaOH缓冲介质中,NPBMT与铜(Ⅱ)形成2:1的桔红色络合物,络合物的最大吸收峰为417nm,表观摩尔吸光系数为2.62×10^4 L·mol^-1·cm^-1,10mL溶液中,铜(Ⅱ)量在0—15μg/mL范围内符合比尔定律。该法用于人发和食品中微量铜的测定,测定结果与AAS法相符。  相似文献   

13.
A copper(Ⅱ) complex [CuL(H2O)(Sal)]·0.5H2O was obtained by the reaction of copper(Ⅱ) salicylate with 3-methyl-4-(4-methylphenyl)-5-(2-pyridyl)-1,2,4-triazole (L) in ethanol-water solution at room temperature. The crystal belongs to triclinic system with space group P1, and a=0.913 6(4) nm, b=1.122 2(5) nm, c=1.263 3(7) nm, α=67.10(2)°, β=76.31(3)°, γ=68.17(2)°, V= 1.101(1) nm3, Z=2. The final refinement gave R1=0.039 8 and wR2=0.106 0 for 3 453 reflections with I>2σ(I). This complex is a good purple fluorescent material in solid state at room temperat-ure. CCDC: 685713.  相似文献   

14.
以3-对溴苯基-4-对甲苯基-5-(2-吡啶基)-1,2,4-三氮唑(L)作为配体,合成了1个铜配合物trans-[CuL2(ClO4)2],对其进行了红外、电喷雾质谱、热重分析和单晶结构表征,该配合物属于三斜晶系,空间群P1,a=0.829 29(15)nm,b=0.854 48(16)nm,c=1.502 7(3)nm,α=83.517(2)°,β=89.200(2)°,γ=73.064(2)°,V=1.011 9(3)nm3,Z=1,R1=0.041 2。单晶结构表明,铜离子处于1个扭曲的八面体配位环境中,2个高氯酸根离子呈反式配位,每个配体L通过三氮唑上的1个氮原子和吡啶氮原子参与配位。热重分析表明该配合物在310℃开始发生分解。  相似文献   

15.
A new copper(Ⅱ)complex,[CuL_2Cl_2]·4H_2O,[L=3-ethyl-4-(p-methoxyphenyl)-5-(2-pyridyl)-1,2,4-triazole],was synthesized and characterized by X-ray crystallography and infrared spectroscopy.The complex crystallizes in triclinic system with space group P(1),α=0.843 9(7)nm,b=0.965 5(8)nm,c=1.093 6(8)nm,α=84.026(19)°,β=82.33(2)°,γ=89.167(19)°,V=0.878 3(12)nm~3,Z=1 with final R=0.033 8.The copper atom lies in a distorted octahedral environment with two bidentate chelating ligands(L)in the equatorial plane and two Cl~- ions in the axial positions.The ligand L coordinates via one triazole nitrogen and one pyridine nitrogen atom.The molecules are stabilized by intermolecular hydrogen bonds in the crystal lattice.CCDC:705817.  相似文献   

16.
合成了双核配合物{Cu2(tacn)2[μ-(MeN)2C2O2]}[(MeNH)2C2O2](ClO4)2(tacn=1,4,7-三氮杂环壬烷)。通过元素分析、红外光谱、ESR谱和电子光谱对配合物进行表征,并利用单晶X射线衍射法测定其结构,晶体属单斜晶系,空间群为P21/n,a=0.72572(16)nm,b=2.5616(6)nm,c=0.9128(2)nm,β=90.096(5)°,V=1.6969(7)nm^3,Dcald=1.590Mg.m^-^3,Z=2,F(000)=840,R1=0.0529,wR2=0.1341,Gof=1.028,△ρ=632~390e.nm^-^3。晶体由对称的双核Cu单元、中性草酰胺分子及高氯酸根堆积而成。两个铜原子配位数为五,处于变形四方锥的配位环境中。在5~300K范围内磁性测定表明:配合物中存在反铁磁偶合相互作用,经理论拟合:g=1.98,J=-219cm^-^1。  相似文献   

17.
A new dinuclear copper(Ⅱ) complex, [Cu(L)(py)]2 1 (H2L = N-(2-hydroxybenzyl)- salicylaldimine, py = pyridine), has been synthesized and characterized by elemental analysis, IR and UV spectra. 1 crystallizes in space group P2 1/n with a = 8.2106, b = 10.715, c = 17.864A, β = 99.365°, V = 1550.7A3, Z = 4, C19H16CuN2O2, Mr = 367.88, Dc = 1.576 g/cm3,μ(MoKα) = 1.422 mm-1, F(000) = 756, the final R = 0.0280 and wR = 0.0746. Complex 1 is a centrosymmetric dimer with two copper(H) centers, two py ligands and two L2- ligands. Each L2- ligand donates its azomethine nitrogen and one of the phenolate groups to one copper(Ⅱ) ion and shares the other phenolate group between the two copper(H) ions, affording a Cu2O2 plane. Each copper(Ⅱ) center has a slightly distorted square pyramidal geometry with a bridging phenolate group at the apex. Magnetic studies suggest the presence of a weak ferromagnetic interaction Via two phenoxo bridges. The magnetic susceptibility data (2-300 K) of complex 1 were analyzed by means of H = -2JS1S2 -DSz. The least-squares fitting of the data to the theoretical equation leads to J = 10.3 cm-1, g = 2.03, D = 0.67 cm-1 and R = ∑(Xobsd -Xcalcd)2/∑Xobsd2= 2.76 × 10^-3.  相似文献   

18.
A new material for both magnetic coupling and electrocatalytic hydrogen generation based on a copper complex,[(HL)CuCl-CuCl(HL)]HCl 1 is prepared by the reaction of 2-(pyridylmethyl)amino-N,N-bis(2-methylene-4,6-difluorophenol)(H_2L) and CuCl_2·2H_2O.In solid,complex 1 is built from two copper units([(HL)CuCl]),and exhibits an antiferromagnetic exchange interaction between copper(Ⅱ) ions(J=-160cm~(-1)).In liquid,1 can electrocatalyze hydrogen generation both from acetic acid with a turnover frequency(TOF) of 16.3 moles of hydrogen per mole of catalyst per hour at an overpotential(OP)of 941.6 mV(in DMF),and a neutral buffer with a TOF of 1415.6 moles of hydrogen per mole of catalyst per hour at an OP of 787.6 mV.  相似文献   

19.
A new dinuclear copper complex, [Cu(C13H9N2O)Cl]2·(CH3CN)2 (C30H24Cl2Cu2N6O2),has been synthesized and characterized by X-ray structure determination. It crystallizes in the triclinic system, space group P1-, with a = 7.6677(14), b = 9.2375(17), c = 11.227(2) (A), α = 81.338(3),β= 88.173(4), γ = 66.199(3)°, V = 718.9(2) (A)3, Z = 1, Mr = 698.53, F(000) = 354, Dc = 1.613 g/cm3,μ(MoKα) = 1.705 mm-1, the final R = 0.0645 and wR = 0.1364 for 2474 unique reflections with 1809 observed ones (I> 2σ(Ⅰ)). In the title complex, each copper(Ⅱ) atom is located at the center of a distorted tetrahedron consisting of four coordinate atoms (one nitrogen atom, two oxygen anions,and one chlorine atom). Two copper(Ⅱ) atoms are bridged by two oxygen anions (O(1) and O(1a)) of two phenolates to form a Cu(Ⅱ)-Cu(Ⅱ) binuclear entity, and the distance between two copper(Ⅱ)atoms is 3.0144(15) (A).  相似文献   

20.
Zhang CY  An CC  Wang RY  Gong YX  Ma H  Chen DY  Chen ZL 《Talanta》2002,58(3):467-473
A new chromogenic reagent, 2-(2-quinolylazo)-5-diethylaminoaniline (QADEAA) was synthesized. A highly sensitive, selective and rapid method for the determination of silver based on the rapid reaction of silver (I) with QADEAA has been developed. In the presence of sodium citrate-sodium hydroxide buffer solution (pH 6.5) and sodium dodecyl sulfonate (SDS) medium, QADEAA reacts with silver to form a violet complex of molar ratio 1:2 (silver to QADEAA). The molar absorptivity of the complex is 1.39x10(5) l mol(-1) cm(-1) at 580 nm. Beer's law is obeyed in the range of 0.01-0.6 mug ml(-1). The relative standard deviation for 11 replicate samples of 0.2 mug ml(-1) is 1.67%. This method can be applied to the determination of silver in water with satisfactory results.  相似文献   

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