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1.
Marczenko Z  Balcerzak M  Kuś S 《Talanta》1980,27(12):1087-1089
The optimum conditions for preparation of stable solutions of ruthenate and osmate, after alkaline fusion of ruthenium(IV) compounds, ruthenium metal and osmium metal in a silver crucible, have been determined. The molar absorptivities of ruthenate and osmate are 1.74 × 103 1. mole−1.cm−1 at 465 nm (Ru) and 2.75 × 103 1.mole−1.cm−1 at 340 nm (Os) in 2M sodium hydroxide. A differential spectrophotometric method has been developed for determination of ruthenium in ruthenium dioxide, lead ruthenite and bismuth pyroruthenate. Simultaneous spectrophotometric determination is proposed for ruthenium and osmium. The other platinum metals interfere seriously only when present in> 1:1 w/w ratio to Ru.  相似文献   

2.
A sensitive flotation-spectrophotometric method for the determination of osmium, based on the ion associate formed by the anionic thiocyanate osmium complex with oxazine basic dye, Capri blue (CB), has been developed. The ion associate is separated by shaking the aqueous solution (pH 2–3) with diisopropyl ether, washing the precipitate with water, and dissolving it in methanol. Molar absorptivity in this method amounts to 2.7 × 105 liters mol−1 cm−1 at 630 nm. The molar ratio Os:SCN:CB in the separated associate is 1:8:5. Under the conditions of the determination of osmium, ruthenium can be determined as well. Metals that form anionic thiocyanate complexes, including other platinum metals, interfere. The method becomes highly selective for osmium and ruthenium after their separation by distillation as tetroxides. Osmium and ruthenium were determined with Capri blue after their extractive separation as thiocyanate complexes.  相似文献   

3.
A sensitive extraction-spectrophotometric method of the determination of osmium, taking advantage of the ion-associate of the chloride osmium anion with brilliant green has been developed. The complex is extracted from aqueous phase with a mixture of C6H5Cl + CCl4 (3 + 1). Molar absorptivity () at 640 nm is 1.95 × 105 liters mol−1cm−1 (specific ABSORPTIVITY = 1.03). The relative standard deviation is 1–3%. The mole ratio of Os:BG in the complex is 1:3. Platinum metals interfere with the determination of osmium. The determination can be highly selective after preliminary separation of osmium by distillation as OsO4.  相似文献   

4.
张丽媛  费旭东  邱丰  林苗 《色谱》2015,33(2):164-168
建立了离子色谱-抑制型电导检测同时测定食品级润滑油中Cl-、NO3-、SO42- 3种代表性无机阴离子的方法。样品经50%(v/v)甲醇水溶液超声提取,离心后所得下层水相用0.22 μm混合纤维过滤膜净化,以15 mmol/L KOH溶液为淋洗液,采用抑制型电导检测器进行检测,外标法定量。在上述条件下,Cl-、NO3-、SO42- 3种无机阴离子在0.10~20.00 mg/L范围内具有良好的线性关系(R2>0.999);检出限(S/N=3)为0.01~0.03 mg/kg;在1.00、5.00、10.00 mg/kg添加水平下,实际样品中3种阴离子的加标回收率为90.0%~103.6%,相对标准偏差为2.8%~5.7%。结果表明,该方法无需燃烧、灰化油相基质等繁琐耗时的前处理过程,可以快速、准确定量测定食品级润滑油中Cl-、NO3-、SO42- 3种无机阴离子的含量,适用于润滑油等油品中痕量无机阴离子的同时分离与测定。  相似文献   

5.
A method has been developed for the spectrophotometric determination of microgram quantities of osmium in uranyl sulphate solutions. The osmium is oxidised to osmium tetroxide, then extracted with chloroform. The extracts are added to an ethanolic solution of 1:5-diphenylcarbohydrazide. A blue-violet coloured reaction product is formed which exhibits maximum absorbancy at 560 mμ. After a period of 2 hr for colour development the molar absorbancy index is about 31,000. Beer's law is adhered to over a range of 30 to 100 μg of osmium with a coefficient of variation of about 4%. A study was made of the effects of foreign substances and only chloride and octovalent ruthenium were found to interfere. Both of these interfering ions can be eliminated.  相似文献   

6.
研究了在OP-10存在下用二苯碳酰二肼测定痕量Os(Ⅳ)的分光光度法。8570nm=3.50×105L·mol-1·cm-1,特征灵敏度为0.057μg/10mL(对应1%吸收)。Os(Ⅳ)与DPCI的组成比为1:1。在0.1~5.0μg/10mL范围内符合比耳定律。  相似文献   

7.
Java S  Ramakrishna TV 《Talanta》1982,29(7):619-622
The formation of the bluish violet osmium-diphenylcarbazide complex in weakly acidic solution is utilized for the determination of osmium by spectrophotometry. When measurements are made at 560 nm, after extraction of the complex into isobutyl methyl ketone, Beer's law is obeyed up to 150 mug of osmium. Relatively few ions interfere, and these can be masked with EDTA and fluoride.  相似文献   

8.
A spectrophotometric determination of osmium has been developed, based on the purple color (absorption maximum at 515 mμ) formed by reaction of osmium with quinisatin oxime in buffered solution of dimethyl formamide and methanol. The absorbances are reproducible, and the system conforms to Beer's law. The method compares favorably in sensitivity with existing methods for osmium. The optimum concentration range (for 1 cm optical path) is about 2 to 10 p.p.m. of osmium. Although the maximum color develops slowly, it is stable for 7 days or longer. Several elements, notably iron, cobalt, and ruthenium, interfere, so that separation, is necessary. A reaction ratio of 1:2 for osmium and quinisatin oxime was clearly indicated; some evidence was also obtained for the presence of higher complexes.  相似文献   

9.
Sulphanilic acid has been found to be a very effective reagent for the spectrophotometric determination (if hexavalent and octavalent osmium in the pH range between 1.8 – 3.5. In these two valence states, the element forms a dark-violet complex with the reagent, the absorption maximum of the complex being at 490 mμ. As most of the other ions interfere in the determination, the element must be separated as osmic acid by nitric acid distillation. Beer's law is obeyed in the case of 0.5 to 9 p.p.m. of osmium (VIII) and l to 18 p.p.m. of osmium (VI); tin-optimum concentration ranges are from 2 to 8 p.p.m. for osmium(VIII) and from 4 to 16 p.p.m. for osmium(Vl). In these ranges, the % relative errors per 1% absolute photometric error are 3.02 for osmium (VIII) and 3.1 for osmium(VI). Application of the method of continuous variations and the molar ratio method indicates that in solution hexavalent osmium and the reagent form a 1:2. complex, with an average dissociation constant of 1.2 ? 10-7.  相似文献   

10.
A sensitive spectrophotometric determination of osmium is based on the blue color (absorption maximum at 615 mμ formed by reaction of osmium with p-(morpholino)-N-(4'-hydroxy-3'-methoxy)benzylidineaniline (“anil”) in acetate-buffered solution containing ethanol to prevent formation of a precipitate, Full color development is attained in I h at room temperature, and the color is stable for several hours. The absorbance is reproducible. The optimum concentration range for I-cm optical path is about I to 4 p.p.m. of osmium. Several transition elements interfere ; osmium can be separated as its tetroxide by the usual distillation method. The blue product is a cationic complex formed by reaction of anil with osmium in a 2 : I mole ratio. When osmium is in excess a red cationic complex (absorption maximum at 466 mμ) is formed by a I : I reaction between osmium and the reagent. The I : I complex is slowly converted to the 2 : I complex by excess reagent.  相似文献   

11.
An ultraviolet spectrophotometric method is presented for the détermination of milligram quantities of osmium in solutions of uranyl sulphate. Osmium is first oxidised to the octovalent state and the osmium tetroxide which is formed, is selectively extracted with chloroform. The ultraviolet absorption spectrum'of osmium tetroxide in chloroform has a series of absorption bands with peak absorbancies at 282, 289, 297, 304 and 312 mμ and molar absorbancy indexes of 1870, 1760,1640, 1400 and 1000, respectively. For each wavelength, the optimum concentration range for the determination of osmium was evaluated. From 0.4 to 3.3 mg of osmium can be determined with a coefficient of variation of 3%. Of the elements tested only chloride and octovalent ruthenium interfere; however, both of these interferences can be eliminated.  相似文献   

12.
An investigation has been made of the organic compound, 1-naphthylamine-3,5,7-trisulfonic acid, for use as a colorimetric reagent for the determination of trace quantities of osniiun(Vl). When this compound is added to an osmium (OsO4-2) solution, a violet colored organo-osmium complex is formed which has highest sensitivity at wavelength 560 mμ. The complex reaches maximum color intensity after four hours. The solution should be brought to pH 1.5 and maintained at tins pH with a buffer, after maximum color development. The colored complex conforms to Beer's law over an osmium concentration range of 0 to 6 p.p.m. Its absorbance is not affected by either excess reagent (up to a 7 : 1 ratio) or by temperature variation over the range 15° to 35° C. Many metallic ions interfere with the color reaction and hence require a separation, of osmium from these ions.The nature of the complex in solution was studied by the following three methods: (1) mole ratio, (2) continuous variations and (3) slope ratio. All three methods indicate a ratio of reagent to osmium of 2 to 1.A procedure for the colorimetric determination of osmium(VI) has been developed; it has a sensitivity of 1 part osmium in 15,000,000 parts of solution, with good precision.  相似文献   

13.
A sensitive flotation—spectrophotometric method, based on the ion associate formed by the anionic thiocyanate complex of osmium with the basic dye methylene blue (MB) is described. The ion associate precipitates when the aqueous solution is shaken with toluene, and the separated and washed compound is dissolved in acetone. The molar absorptivity is 2.2 × 105 l mol-1 cm-1 at 655 nm. Beer's law is obeyed. The molar ratio of Os:SCN:MB in the separated and washed ion associate is 1:6:3. Ruthenium reacts similarly. The method is applied to the determination of traces of osmium in crucible platinum after separation of osmium by distillation as tetroxide.  相似文献   

14.
A highly sensitive indirect spectrophotometric red-ox method for the determination of osmium is reported. The method is based on the oxidation of iodide by osmium (Ⅵ) and the spectrophotometric detection of the liberated iodine in the form of complex anion and ion associate with 2-(4-diethylaminostyryl)-1,3,3-trimethyl-6-nitro-3H-indolium chloride reagent. The appropriate reaction conditions have been established. The molar absorptivity is ( 1.6-5.6) × 10^4 L mol^-1 cm^-1. Beer's law holds for the concentration range of 0.5-11.4 μg mL^-1 of Os(Ⅵ).  相似文献   

15.
Norwitz G  Gordon H 《Talanta》1975,22(7):593-596
Methods are proposed for the determination of soluble styphnate and nitrate in waste-water from lead styphnate primer plants. The styphnate is extracted from the waste-water with methylene chloride and is determined by measurement of the absorbance of the methylene chloride solution at 273 nm. The nitrate is determined in the aqueous solution left after the methylene extraction by measurement of the absorbance at 220 nm. For complete extraction of the styphnate by the methylene chloride, the solution must be moderately acidic (about 6% perchloric acid). The acidity for the determination of the nitrate is not critical. Before the determination of the nitrate in the aqueous extract, it is necessary to boil the solution to eliminate residual methylene chloride which would interfere with the determination of nitrate. PETN is extracted by the methylene chloride but does not interfere with the determination of the styphnate, since it shows no interfering peaks. Chloride, sulphate, phosphate, fluoride and carbonate do not interfere with the determination of styphnate or nitrate.  相似文献   

16.
A highly sensitive and selective fluorescence-quenching kinetic method is proposed for the determination of trace osmium(IV), based on the catalytic effect of osmium(IV) on the salicylfluorone (ex = 510 nm, em = 535 nm)-H2O2 system at pH 9.3–9.6. Using the fixed time method, osmium(IV) in the range 0.008–0.6 ng/ml can be determined. The detection limit is 0.006 ng/ml. Over thirty anions and cations, including other platinum metal ions, do not interfere, even when present in large excess. The method has been applied successfully for the determination of osmium in a series of synthetic mixtures and refined ore with relative standard deviations of 2–6%.  相似文献   

17.
示波极谱滴定研究(Ⅸ)——四苯硼钠滴定钾   总被引:5,自引:0,他引:5  
提出了一个用四苯硼钠在交流示波极谱图上的切口来指示终点的测定常量钾的容量方法。方法快速、准确,干扰很少。  相似文献   

18.
Balcerzak M  Swicicka E 《Talanta》1996,43(3):471-478
Ruthenium and osmium (up to 20 mug Ru(Os) ml(-1)) can be determined in chloride solutions directly after absorption of RuO(4) and OsO(4) in hydrochloric acid. In 9 M HCl, RuO(4) and OsO(4) are quantitatively converted into RuCl(6)(2-) (lambda(max) = 480.0 nm, epsilon = 4.8 x 10(3) l mol(-1) cm(-1)) and OsCl(6)(2-) (lambda(max) = 334.8 nm, epsilon = 8.4 x 10(3) l mol(-1) cm(-1)) respectively. Osmium does not interfere with the determination of ruthenium in the form of the RuCl(6)(2-) complex by direct spectrophotometry. The absorbance of the obtained solution at lambda(max) = 480.0 nm corresponds only to the concentration of ruthenium. A derivative spectrophotometric method using numerical calculation of absorption spectra of the RuCl(6)(2-) and OsCl(6)(2-) complexes has been developed for the determination of osmium in a mixture with ruthenium. The interfering effect of ruthenium on the determination of osmium can be eliminated by measuring the value of a third-order derivative spectrum of the OsCl(6)(2-) complex at 350.0 nm ("zero-crossing point" of ruthenium). Simple and rapid determination of ruthenium and osmium in a calibration standard solution of the noble metals (Ru, Rh, Pd, Os, Ir, Pt and Au) for plasma spectroscopy using the proposed methods has been achieved.  相似文献   

19.
Agarwala BV  Ghose AK 《Talanta》1973,20(1):129-130
Osmium(VIII) produces two coloured species with lambda(max) 680 nm (green) and 530 nm (red) with excess of 2-amino-8-naphthol-3,6-disulphonic acid in aqueous solution. The green complex is stable between pH 2.5 and 8.0 and the red complex between pH 11.0 and 12.0. The effects of temperature and time, reagent concentration, optimum conditions for the spectrophotometric determination of trace amounts of osmium, and other variables, have been studied at pH 11.5. At this pH, other platinum metals do not interfere. The sensitivity of the colour reaction is 0.2 microg/cm(2) and the system conforms to Beer's law over a concentration range of 1.5-10 microg of osmium.  相似文献   

20.
武鑫  马骏  南明  双少敏  董川 《应用化学》2016,33(3):357-363
以荧光素酰肼与5-溴水杨醛反应合成了一种新型荧光素衍生物5-溴水杨醛荧光素腙(BSFH),采用红外、核磁、质谱、元素分析等技术手段对其进行了表征。 通过吸收光谱考察了在水溶液中BSFH对常见金属离子的选择性响应,发现BSFH在可见光区几乎无吸收,当加入常见金属离子时,吸收光谱上除了Cu2+之外的其它金属离子在496 nm处出现非常弱的吸收,而当Cu2+存在时,可以裸眼看到溶液颜色迅速从无色变为黄色,吸收光谱上在496 nm处出现了相对很强的吸收峰,并且随着Cu2+浓度的增加溶液的吸收强度不断增强,说明在水溶液中BSFH对Cu2+有很好的选择性。 实验结果表明,该化合物与Cu2+的化学计量比为1:1,Cu2+浓度线性范围为0.30~10 μmol/L,许多常见的金属离子不干扰Cu2+的测定,检测限为0.30 μmol/L,说明在水溶液中BSFH对铜离子具有很高的灵敏度。 据此,BSFH可以简单、快速、灵敏地在水溶液中识别和检测低浓度的铜离子。  相似文献   

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