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1.
本文以2-(2-噻吩偶氮)-5-二乙氨基酚(简称TADAP)作柱前显色剂,反相色谱法分离测定铜(Ⅱ)、钴(Ⅱ)、镍(Ⅱ)离子。用含有1.5×10~(-4)mol/L的TADAP,0.1mol/L氯化锂和0.1mol/L乙酸盐(pH4)的甲醇(60%)-水(40%)溶液作为流动相,流量为0.9ml/min,紫外-可见检测器检测波长为545nm。在此条件下,铜(Ⅱ)、钴(Ⅱ)、镍(Ⅱ)螯合物得到最佳分离,并定量测定了茶叶中铜、钴、镍的含量,与原子吸收分光光度法测定,得到一致的结果。  相似文献   

2.
研究了1-(5-溴-2-吡啶偶氮)-2-萘酚-6-磺酸与钴(Ⅱ)和镍(Ⅱ)之螯合物的衍生和液相色谱分离条件。于Zorbax ODS柱上,用含0.01mol/L HAC-NaAc(pH 5.5)的乙腈-四氢呋喃-水(24:5:71,V/V)作流动相,流速0.7ml/min淋洗,于570nm检测。本方法已用于镍矿、催化剂回收液和人发样品的分析。  相似文献   

3.
本文采用新试剂2-(5-硝基-2-吡啶偶氮)-5-二乙氨基苯酚(5-NO_2-PADAP)为柱前衍生试剂,不需对离子试剂,用含40mmol/L 的 pH6.0的乙酸-乙酸钠缓冲溶液和10~(-4)mol/LEDTANa_2的甲醇-水溶液(67.5:32.5)为流动相,在 ODS 柱上,20min 内 HPLC 测定了 Fe(Ⅲ)、CO(Ⅱ)和 Ni(Ⅱ)的5-NO_2-PADAP 的络合物,这是同类衍生试剂中最简单流动相体系。当信噪比 SNR=2时,检出限分别为0.17、0.17和0.09ng/ml。是同类体系中灵敏度最高的。方法用于同时测定硝酸试剂和茶叶中的铁、钴和镍,结果良好。  相似文献   

4.
研究了丁二酮肟 氨 氯化铵 柠檬酸钠 明胶 抗坏血酸体系中Cu(Ⅱ )、Cd(Ⅱ )、Ni(Ⅱ )和Co(Ⅱ )的络合物吸附波 ,建立了同时、快速测定锌电解溶液中这些痕量元素的新方法。Cu(Ⅱ )、Cd(Ⅱ )、Ni(Ⅱ )和Co(Ⅱ )分别在 - 0 44V、- 0 76V、- 1 0 7V和 - 1 2 4V左右产生灵敏的络合物吸附波。信噪比为 3时 ,其检测限分别为 1 0× 1 0 - 8mol/L、1 3× 1 0 - 8mol/L、2 9× 1 0 - 1 0 mol/L和 3 6×1 0 - 1 1 mol/L。铜、镉、镍和钴的浓度分别为 2 0× 1 0 - 8mol/L~ 2 0× 1 0 - 5 mol/L、3 0× 1 0 - 8mol/L~ 3 0× 1 0 - 5mol/L、5 4× 1 0 - 1 0 mol/L~ 5 4× 1 0 - 7mol/L和 6 8× 1 0 - 1 1 mol/L~ 6 8× 1 0 - 8mol/L时 ,与相应峰电流之间有良好的线性关系。方法已用于锌电解液中铜、镉、镍和钴的快速同时测定 ,相对标准偏差分别小于或等于 4 7%、5 1 %、4 9%和 5 3 %。  相似文献   

5.
本文报道了同时测定钴和镍的一种方法.在 0.01mol/L NH_3·H_2O-0.01mol/LNH_4Cl-3.0×10~(-5)mol/L安息香缩氨基硫脲(BTSC)溶液中,钴(Ⅱ)和镍(Ⅱ)均产生非常灵敏的还原波,其峰电位分别是:-0.94和-0.75V(vs.SCE),峰电流与钴和镍的浓度分别在2.0×10~(-8)~1.0×10~(-6)和1.0×10~(-8)~8.0×10~(-7)mol/L范围内成直线关系,该方法用于测定水中痕量钴和镍,相对标准偏差分别为1.4~2.0%和2.1~2.5%,回收率分别在98.0%~101.8%和97.9%~102.1%之间.  相似文献   

6.
用2-QADN2,7-金属络合物示波极谱法同时测定铜镍钴镉   总被引:1,自引:0,他引:1  
本文研究了2-QADN2,7-金属络合物的极谱特性。在pH9.60的缓冲溶液中,Cu(Ⅱ)、Ni(Ⅱ)、Co(Ⅱ)和Cd(Ⅱ)与2-QADN2,7的络合物在-0.37、-0.69、-0.77和-0.82V产生灵敏的极谱波,利用这些波可测定痕量的铜、镍、钴和镉。铜的检测下限为2.0×10~(-8)mol/L,镍、钴及镉的检测下限为5.0×10~(-8)mol/L。提出的方法用于同时测定头发和茶叶中的痕量铜、镍和钴,结果满意。  相似文献   

7.
本文研究了水溶性试剂1-(2-吡啶偶氮)-2-萘酚-6-磺酸(PAN-S)与铁(Ⅱ)、钴(Ⅱ)和镍(Ⅱ)之螯合物的衍生和液相色谱分离条件.在Nova-PakTMC18柱上,用含10mmol/L的pH5.0的醋酸-醋酸钠缓冲溶液的甲醇-水溶液(50:50,V/V)作流动相,溴化四丁基铵(TBA·Br)作离子对试剂,流动相流速为1.0mL/min,在550nm波长处进行光度检测.在Ⅱmin内用高效液相色谱分离测定了Fe(Ⅱ)、Co(Ⅱ)和Ni(Ⅱ)与PAN  相似文献   

8.
试验合成了一种荧光试剂对-氨-苯基卟啉(TAPP),该试剂与钴(Ⅱ)离子和镍(Ⅱ)离子反应发生荧光淬灭,据此试验了以其为探针测定痕量钴(Ⅱ)和镍(Ⅱ)的荧光分光光度法。在pH7.2的Tris-盐酸缓冲介质中,在一定量的十二烷基硫酸钠(SDS)存在下,通过测定样品溶液和空白溶液在激发波长392 nm和发射波长516 nm处的发射荧光强度F_s及F_0,计算得反应液荧光强度减弱程度△F,其结果表明:△F与钴(Ⅱ)和镍(Ⅱ)的浓度均在2.0×10~(-7)~1.0×10~(-5)mol·L~(-1)范围内呈线性关系,方法的检出限(3S/N)分别为2.0×10~(-8)mol·L~(-1)和4.0×10~(-8)mol·L~(-1)。此方法用于自然水体和污水中钴(Ⅱ)和镍(Ⅱ)的测定,回收率分别在97.0%~108.5%和97.0%~106.5%之间。  相似文献   

9.
本文在自行合成水溶性螯合剂双(2-羟乙基)二硫代氨基甲酸铵基础上,研究其与镉(Ⅱ),铅(Ⅱ),钴(Ⅱ),镍(Ⅱ),铜(Ⅱ),汞(Ⅱ)之螯合物的液相色谱分离条件。于Nucleosil C_(18)柱上,用合0.05mol/L K_2HPO_4(pH=6.0)和0.01mol/L TBAP的甲醇-水(40:60,V/V)做流动相,流速0.8ml/min淋洗,于电位为+0.90V(vs.SCE)检测。对十七种元素做了干扰实验,除As对Ni峰,Se对Cu峰有干扰外,其它元素均无干扰。大量Co存在不影响Ni的测定。  相似文献   

10.
激光热透镜光谱分析法同时测定铜、钴和镍研究   总被引:1,自引:0,他引:1  
基于2-(5-NO2-吡啶-2-偶氮)-1-羟基-8-氨基萘-3,6-二磺酸与铜(Ⅱ)、钴(Ⅱ)和镍(Ⅱ)反应酸度的差异及热透镜信号强度的加和性,建立了激光热透镜光谱法同时测定铜、钴和镍的新方法。测定铜、钴和镍的线性范围依次为0~200ng/mL、0~200ng/mL和0~100ng/mL,检出限依次为2ng/mL,2.5ng/mL和1ng/mL。方法已用于合成样品及人发样中铜、钴和镍的同时测定。  相似文献   

11.
On the Existence of Polynary Oxides of the Alkali Metals with Monovalent Cobalt and Nickel For the first time we obtained RbNa2NiO2, KNa2NiO2, Na3CoO2 and K3CoO2 [RbNa2NiO2: Na2NiO2 + Rb2O, Rb:Ni = 1.8:1, 600°C, 28 d, Ni-tube; KNa2NiO2: Na2NiO2 + K2O, K:Ni = 1.8:1, 600°C, 20 d, Ni-tube; Na3CoO2: Na2O + CoO: Na:Co = 8.8:1, 500°C, 20 d, Co-tube; K3CoO2: K2O + CoO: K:Co = 4.4:1, 550°C, 20 d, Co-tube]. According to X-ray structure analysis of single crystals monovalent Co and Ni is present [always four-circle-diffractometer data, MoKα -radiation; RbNa2NiO2: AED 2, all 163 Io(hkl), R = 3.4%, Rw = 1.9%, I4/mmm, a = 461.7(1), c = 973.6(3) pm, Z = 2; KNa2NiO2: AED 2, all 341 Io(hkl), R = 5.6%, Rw = 3.5%, Cmma, a = 1 048.5(3), b = 626.8(1), c = 621.9(1) pm, Z = 4; Na3CoO2: PW 1 100, 517 of 568 Io(hkl), R = 2.9%, Rw = 1.8%, P42/mnm, a = 940.0, c = 464.5 pm, Z = 4; K3CoO2: PW 1 100, all 940 Io(hkl), R = 5.0%, Rw = 3.9%, Pnma, a = 1 190.0, b = 730.4, c = 604.1 pm, Z = 4]. All samples are red, the single crystals transparent. Two O2? coordinate Ni1+ and Co1+, respectively, like a dumb-bell. Mean Fictive Ionic Radii, MEFIR, and Effective Coordination Numbers, ECoN, and Madelung part of lattice energy, MAPLE, are given.  相似文献   

12.
The activity and selectivity of 10 % Co/support and 10 % Ni/support catalysts (where the support is A12O3, SiO2, C) in the synthesis of hydrocarbons from CO2 and H2 were studied. The extent of conversion of the starting mixture and the yield of methane were shown to depend on the composition of the catalytic system. Cobalt catalysts with various types of carbons as supports are the most active. They permit the synthesis of methane in yields up to 70 % of the theoretical value.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 482–484, March, 1993.  相似文献   

13.
简易高效液相色谱分光光度仪的研制   总被引:2,自引:1,他引:1  
  相似文献   

14.
This paper reports the analysis of mixtures of nickel and copper, by means of a complex formation reaction and use of the following differential kinetic methods: logarithmic extrapolation, single-point, and reaction rate. All three methods give similar relative standard deviations, but the concentration ratio range in the logarithmic extrapolation method is wider than in the other two. The logarithmic extrapolation method allows determination of nickel and copper in ratios ranging from 1.51 to 16.  相似文献   

15.
The mixed ligand complexes of Cu(II), Ni(II) and Co(II) with uridine and amino acids, L-alanine, L-phenylalanine and L-tryptophan were synthesized and characterized by elemental analysis, conductivity data, infrared spectra, electronic spectra and magnetic susceptibility data. In these complexes, the nucleoside (uridine) acts as a monodentate ligand coordinating through O(4) under the conditions of investigation, whereas the amino acids coordinate through the carboxylate oxygen and the amino nitrogen. Distorted octahedral geometry for Cu(II) and octahedral geometries for both Ni(II) and Co(II) are proposed.  相似文献   

16.
Dissolution rates of NiO, CoO, ZnO, α-Fe2O3 and the corresponding ferrites in 0.1 mol dm−3 oxalic acid at pH 3.5 were measured at 70 °C. The dissolution of simple oxides proceeds through the formation of surface metal oxalate complexes, followed by the transfer of surface complexes (rate-determining step). At constant pH, oxalate concentration and temperature, the trend in the first-order rate constant for the transfer of the surface complexes (kMe; Me=Ni, Co, Zn, Fe) parallels that of water exchange in the dissolved metal ions (k−w). Thus, the most important factor determining the rates of dissolution of metal oxides is the lability of Me-O bonds, which is in turn defined by the electronic structure of the metal ion and its charge/radius ratio. UV (384 nm) irradiation does not increase significantly the dissolution rates of NiO, CoO and ZnO, whereas hematite is highly sensitive to UV light. For ferrites, the reactivity order is ZnFe2O4>CoFe2O4?NiFe2O4. Dissolution is congruent, with rates intermediate between those of the constituent oxides, Fe2O3 and MO (M=Co, Ni, Zn), reflecting the behavior of very thin leached layers with little Zn and Co, but appreciable amounts of Ni. The more robust Ni2+ labilizes less the corresponding ferrite. The correlation between log kM and log k−w is somewhat blurred and displaced to lower kM values. Fe(II), either photogenerated or added as salt, enhances the rate of Fe(III) phase transfer. A simple reaction mechanism is used to interpret the data.  相似文献   

17.
本文报道了以2-(6-甲基-2-苯并噻唑偶氮)-5-二乙氨基酚(MBTAE)作柱前衍生化试剂,在SpherisorbC_8柱上,以甲醇:水=80:20(V/V),含2mmol/LLi_2SO_4和10mmol/LpH5.0醋酸盐缓冲溶液作流动相,反相高效液相色谱分离和测定了Fe ̄(2+)、Co ̄(2+)、Ni ̄(2+)和Cu ̄(2+)。各金属离子的检出限(S/N=3)分别为(pg):Fe ̄(2+)6.40,Co ̄(2-)1.38,Ni ̄(2+)4.47,Cu ̄(2+)7.28。方法用于欧洲标准局,黑麦草标样的分析,所得结果与标准值相符。  相似文献   

18.
19.
用偏最小二乘法(PLS)和多元线性回归法(MR)分别对钴、镍、铜三组分混合体系进行同时测定,证明PLS法对光谱重叠严重的体系较MR法有更好的预报准确性.着重讨论了校正集样品数n、波长数,和特征变量数d等测定参数对预报结果的影响.  相似文献   

20.
采用热沉淀法制备了纳米级(粒径在15~30nm)非负载Ni(Co)-Mo-Al2O3催化剂,并用BET、XRD、SEM、TEM等技术对催化剂进行了表征;并以乙酸为探针分子,在连续流动固定床反应器上评价了催化剂的加氢脱氧活性,考察了Ni、Co活性组分、焙烧温度对催化剂的晶态结构及催化性能的影响.结果表明:在考察的反应条件下,Ni、Co活性组分加入后,使Mo-Al2O3催化剂的活性明显提高;而且Ni-Mo-Al2O3催化剂的加氢脱氧活性明显高于Co-Mo-Al2O3催化剂的活性;焙烧温度由500℃升高到550℃时,催化剂的比表面积增大,晶化度提高,催化剂的活性提高.  相似文献   

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