首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
1.
硫酸铵-硫氰酸铵-乙醇体系萃取浮选 Cu(Ⅱ)   总被引:5,自引:3,他引:2  
研究了在少量抗坏血酸存在下,硫酸铵-硫氰酸铵-乙醇体系萃取浮选Cu(Ⅱ)的行为。Cu(Ⅱ)被抗坏血酸还原为Cu(Ⅰ)后能与SCN-生成CuSCN沉淀。该沉淀可以被萃取浮选在乙醇与水两相界面之间。PH1~4时,能使Cu(Ⅱ)与常见离子Fe(Ⅲ)、Co(Ⅱ)、Ni(Ⅱ)、Mn(Ⅱ)、Zn(Ⅱ)、Cd(Ⅱ)、Cr(Ⅲ)、Mo(Ⅳ)分离。  相似文献   

2.
用环氧氯丙烷低聚物分别与二(三)乙醇胺的钠盐进行反应,合成了两种氨杂冠醚型交联树脂,研究了树脂对贵金属和一些d-过渡金属的吸附性能,树脂Au(Ⅲ)具有较高的吸附容量和吸附率。在Cu(Ⅲ)-Pd(Ⅱ)-Pt(Ⅳ)混合液中优先吸附Au(Ⅲ);在Cu(Ⅱ)-Zn(Ⅱ)和Cu(w)-Co(Ⅱ)-Ni(Ⅱ)的混合液中只吸附Cu(Ⅱ)而不吸附其他金属离子。  相似文献   

3.
邓凡政  石影 《分析化学》1997,25(2):215-218
研究了在聚乙二醇-硫酸铵-铝试剂体系中Fe(Ⅲ),Al(Ⅲ)、Cu(Ⅱ)、CoⅡ)Cd(Ⅱ)Mn(Ⅱ)、Ni(Ⅱ)的萃取分离行为。结果表明,在PH5.0-6.5HAc-NaAc缓冲溶液中,Fe(Ⅲ)、Al(Ⅲ)可被PEG相几乎完全萃取,而Cu(Ⅱ)、Co(Ⅱ)Cd(Ⅱ)Mn(Ⅱ)基本上不被萃取,从而实现了Fe(Ⅱ)与Cu(Ⅱ)Co(Ⅱ)Cd(Ⅱ)Mn(Ⅱ)及Al(Ⅲ)与Fe(Ⅲ)Co(Ⅱ)、Cu(  相似文献   

4.
提出了Cu(Ⅱ)-茜素红S-甲基紫-聚乙烯醇三元配合物体系光度法测定Cu(Ⅱ)的新方法,在聚乙烯醇存在的下,Cu(Ⅱ)-茜素红S-甲基紫形成稳定的有色配合物,通过测定该化合物的吸光度而测定Cu(Ⅱ)含量,测定了天然水样,试验表明,方法有较好的灵敏度和选择性,精密度可靠,适用于水样中痕量Cu(Ⅱ)的测定。  相似文献   

5.
用环氧氯丙烷低聚物分别与二(三)乙醇胺的钠盐进行反应,合成了两种氮杂冠醚型交联树脂.研究了树脂对贵金属和一些个过渡金属的吸附性能.树脂对Au(Ⅲ)具有较高的吸附容量和吸附率。在Cu(Ⅲ)-Pd(Ⅱ)-Pt(Ⅳ)混合液中优先吸附Au(Ⅲ);在Cu(Ⅱ)—Zn(Ⅱ)和Cu(Ⅱ)—Co(Ⅱ)—Ni(Ⅱ)的混合液中只吸附Cu(Ⅱ)而不吸附其他金属离子.  相似文献   

6.
林秋月  李伟琦 《分析化学》2000,28(7):883-886
研究了(NH4)2SO4-Zincon(锌试剂)-Tween80体系萃取分离金属离子Cu(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)、Zn(Ⅱ)、Cd(Ⅱ)、Mn(Ⅱ)的行为。试验表明,Cu(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)在PH-6-9范围内,与Zincon形成的螯合物可被Tween80相完全萃取,而Zn(Ⅱ)、Cd(Ⅱ)基本不被萃取,进而实现了Cu(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)与Zn(Ⅱ)、Cd(Ⅱ)、Mn(0  相似文献   

7.
林秋月  李伟琦 《分析化学》2000,28(6):706-708
研究了(NH4)2SO4-Zincon(锌试剂)-Tween-80体系萃取分离金属离子Cu(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)、Zn(Ⅱ)、Cd(Ⅱ)、Mn(Ⅱ)的行为。试验表明,Cu(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)在pH6 ̄9范围内,与Zincon形成的螯合物可被Tween-80相完全萃取,而Zn(Ⅱ)、Cd(Ⅱ)、Mn(Ⅱ)基本不被萃取,进而实现了Cu(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)与Zn(Ⅱ)、Cd(  相似文献   

8.
邓凡政  石影 《分析化学》1995,23(7):832-834
本研究了聚乙二醇(PEG)-(NH4)2SO4-铬黑T(EBT)体系对Fe(Ⅲ)、Co(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)、Cd(Ⅱ)的非有机溶剂萃取行为。结果表明,在pH7 ̄11的NH3·HNHCl缓冲溶液中,Fe(Ⅲ)、Co(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)可被聚乙二醇(PEG)相萃取,而Cd(Ⅱ)基本上不被萃取,从而获得了Cd(Ⅱ)与Fe(Ⅲ)、Co(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)混合离子的定量分离。  相似文献   

9.
周光明  盛蓉生 《分析化学》1995,23(9):1022-1027
本文在银胶活性基质上获得了Cu(Ⅱ)的中位-四(4-N-氰甲基吡啶)卟啉络合物Cu(Ⅱ)NACN的表面增强喇曼光谱光谱,并与其RRS光谱作了比较,讨论了PH值和Cu(Ⅱ)NACN的复合物的SERS光谱的影响,研究了小牛胸腺双链DNA及其变性DNA与Cu(Ⅱ)NACN的复合物的SERS光谱,指出Cu(Ⅱ)NACN是通过吡啶氮和卟啉核共同与银胶作用的,Cu(Ⅱ)NACN是斜向吸附在银表面上的,最佳PH  相似文献   

10.
以金属Ni(Ⅱ)离子为模板,合成了高分子多乙烯多胺络合吸附剂。研究了它们对重金属离子(Cu^2+,Ni^2+,Zn^2+,Co^2+)的吸附特性。结果表明,这类吸附剂对Cu(Ⅱ)、Ni(Ⅱ),Zn(Ⅱ)、Co(Ⅱ)离子的吸附容量分别达239.60、231.30、131.83、81.23mg/g(干);相应选择性顺序为Cu(Ⅱ)≈Ni(Ⅱ)>Zn(Ⅱ)>Co(Ⅱ)。  相似文献   

11.
Hypoxia-inducible factor-1 (HIF-1) is among the most important indicators of hypoxia in evaluating severity of many diseases. In this work, a novel method for HIF-1 detection is proposed by using electrochemical techniques based on small molecule binding DNA. In this method, since the designed DNA sequence can specifically bind with either an electroactive small molecule or HIF-1, the signal readout is inversely proportional to HIF-1 concentration, thus a simple and easily-operated method for HIF-1 detection can be developed. With the proposed method, HIF-1 can be determined in a linear range from 5 to 25 nM with a detection limit of 2.8 nM. Furthermore, the proposed method can be directly used to assay HIF-1 in placenta tissue, and the assay results can reliably reflect the severity of preeclampsia, a very dangerous condition during pregnancy. The proposed method also shows desirable sensitivity, high selectivity and excellent reproducibility, so this method can have potential applications in clinical practice.  相似文献   

12.
A simple, direct microanalytical method for quantitative determination of silicon in human whole blood, serum, urine, and milk by furnace atomic absorption technique has been developed. The method employs standard additions and combines the inherent specificity and simplicity of atomic absorption analysis with the greatly increased sensitivity possible with a heated graphite tube atomizer for the determination of silicon in microliter samples. The sensitivity of the method is 1.3 ng. The method is suitable for the direct analysis of silicon with no sample preparation other than dilution with deionized water, thereby minimizing contamination due to sample preparation. The relative standard deviation for 10 μl of blood (1:1), serum (1:1), urine (1:7), and milk (1:1) was 3.45% or less.  相似文献   

13.
Ramachandran KN  Kumar GS 《Talanta》1996,43(10):1711-1714
Reaction of selenium with 2,3-diaminonaphthalene was reinvestigated with bromide ion as a catalyst. In acid medium, selenium reacts with the above reagent to form a complex extractable with cyclohexane and with an absorption maximum at 378.5 nm. The molar absorptivity of the complex is 17.5 x 10(3) 1 mol(-1) cm(-1). Beer's law is obeyed in the range 0.5-12 mg 1(-1). The method is reproducible and the standard and relative standard deviation for seven replicate analyses of 2 mg 1(-1) of selenium are 0.05 absorbance units and 2.5%, respectively. The limit of detection is 0.012 mg 1(-1). The method was optimized for the determination of selenium in water, soil, cereal and mineral mixtures and cattle feed and was compared with the reported 2,3-diaminonaphthalene method.  相似文献   

14.
依据地球化学样品分析方法第4部分:金量的测定泡塑富集-电感耦合等离子体质谱法。在大量实践的基础上总结了样品前处理过程中样品的焙烧、溶样、振荡吸附、解脱时间的合理控制,以及样品分析前处理过程中的一些操作注意事项。最终确定样品焙烧时间1h,溶样时间40min,震荡吸附时间30min,硫脲水浴解脱时间30min。经过对大批量实验样品及国家一级金标准物质测定验证后得出:适当优化条件可以满足绝大多数样品的分析准确度、精密度等质控分析要求,并且可以提高分析效率。尤其对于大批量分析任务,如区域化学地质普查。可以在相同的实验设备、人员配备的基础上,提高分析效率,降低能耗。  相似文献   

15.
Abstract

A gas chromatographic method for the determination of N,N-dialkyl dithiocarbamates in industrial wastewater at the nanogram level is described. The sample is freeze-dried, extracted with ethanol and then esterified with 1-iodopropane. The method is sensitive, specific, and free from interference of metals. The sensitivity of the method is in the order of 1 ng (injected).  相似文献   

16.
A modification of the conventional static head-space gas chromatography method (SHSGC method) to determine stability constants for 1-alkanol/alpha-CD inclusion complexes was investigated. The 1 : 1 stability constants determined by this modified SHSGC method are in reasonable agreement with the corresponding values reported previously. The modified SHSGC method precludes the necessity of the calibration curve by the use of Henry's law constant of guest. Consequently, the modified SHSGC method is more advantageous than the conventional SHSGC method because the experimental time required for determination of the stability constant is markedly reduced.  相似文献   

17.
Afkhami A  Zarei AR 《Talanta》2003,60(1):63-71
The H-point standard addition method (HPSAM), based on spectrophotometric measurement, for simultaneous determination of periodate-bromate and iodate-bromate mixtures is described. This method is based on the difference between the rates of their reactions with iodide in acidic media. The results showed that simultaneous determinations could be performed with the ratio 1:15-12:1 for periodate-bromate and 15:1-1:15 for iodate-bromate. The proposed method was successfully applied to the simultaneous determination of periodate-bromate and iodate-bromate in water and synthetic samples.  相似文献   

18.
Mesoporous molecular series Ti-KIT-1 samples were prepared by three different post-handling methods using Ti(OEt)4 as the Ti source and KIT-1 as the support .The three post-synthetic methods were impregnated method,grafting method and colloidal method.The Ti-KIT-1 samples were characterized by FT-IR,DRS,XRD,TG-DSC and physical adsorption-desorption of nitrogen.Experimental results showed that the Ti-KIT-1 samples remained the original mesoporous structure with a smaller specific BET surface area compared to the parent KIT-1 sieve.DRS and FT-IR indicate the existence of tetrahedral titanium (Ⅳ),TG-DSC and chemical analyse method proved that TiO_2 weight percentage of grafting sample is much more than impregnated and colloidal samples.The grafting method is a good post-handling method that can effectively make use of a titanium source and promise the original mesoporous structure.  相似文献   

19.
A photometric method for hydrogencarbonate determination in various natural waters is presented, based on measurements with methyl red. Accuracy of the results is demonstrated by comparison with titrimetric and ion-chromatographic methods. The photometric method is suitable for contents in the range of 1–2000 mg l?1. The linear range of the continous flow method varies form 6–60 mg l?1 to 12–90 mg l?1 depending on conditions.  相似文献   

20.
In this study, we have developed a new method to synthesize mesoporous titanium silicalite-1 (TS-1) with a higher content of active titanium in the framework (more than 5%) than that obtained from the conventional hydrothermal synthesis. The new method combines two methods as follows: (1) a sol-gel method in tetrahydrofuran for the synthesis of TiO2–SiO2 composite with highly dispersed Ti species and (2) a dry gel conversion method for the crystallization to TS-1. This investigation revealed that the dispersion of Ti in the starting materials was quite important to synthesize mesoporous TS-1 with high content of Ti besides dry conversion method. The obtained mesoporous TS-1 with a high content of titanium showed higher catalytic activity in 1-hexene epoxidation than conventional TS-1. This high activity is likely to originate from the high content of titanium in the framework.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号