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PubMed2002

[The simultaneous determination of iron(III) and aluminium(III) in quartz sand by first derivative spectrophotometry].

It is found that in a buffer solution of HAc-NaAc (pH-6.0), iron (III) and aluminium (III) react with ethylene glycol diethy diaminoteracetic acid (EGTA), pyrogallol red (PR) and cetylpyridinium bromide (CPB) to form quarternary complex. Micro iron (III) and aluminium (III) can be simultaneous determined by the first derivative spectrophotometry of the quarternary complex. The RSD for the determinations of iron and aluminium are 4.5% and 1.1% respectively, and the recoveries are 93%-98% and 95%-102% respectively. This method has been applied to the determination of micro iron and aluminum in quartz sand with satisfactory results.

Aluminum↗
PubMed2001

[Simultaneous determination of cobalt and nickel in catalyst by microwave digestion-dual wavelength equal absorption spectrophotometry].

Catalyst samples are digested in a microwave digestion system. The optimum parameters for microwave digestion are selected. Cobalt and nickel in the mixture of Co2+ and Ni2+ with 4-(2-pyridylazo) resorcinol (PAR) can be determined simultaneously by dual-wavelength equal absorption spectrophotometry. By means of the combination of two methods, Co2+ and Ni2+ in catalyst can be determined rapidly, accurately, and contamination problems avoided. The linear ranges are 0-30 micrograms.25 mL-1 for Co2+ and 0-25 micrograms.25 mL-1 for Ni2+. The recoveries of Co2+ and Ni2+ in synthetic samples are between 98.2%-103.6% and between 97.9%-103.7%, respectively. The relative standard deviations of analytical results in catalyst samples are less than 2.2% for Co2+ and less than 1.8% for Ni2+, and relative errors are less than +/- 2.5% for Co2+ and Ni2+.

Catalysis↗
PubMed2001

[Determination of trace as in health-giving drink by AA-670 atomic absorption spectrophotometry attached VA-90 atomization].

A new method has been developed for the determination of trace metal As in health-giving drink by AA-670 atomic absorption spectrophotometry attached VA-90 atomization. The method is convenient to determine element in water. The results show that the method has good precision and accuracy. The detection limit is 2 ng.L-1 for As. The relative standard deviation is 5.4%-6.1%, and the rates of recovery is 87.5%-115%. This method has been applied to the determination of health-giving drink with satisfactory results.

Arsenic↗
PubMed2001

[Study of direct determining animal and plant oil in sewage by ultraviolet spectrophotometry method].

In this paper, the trace oil in sewage have been emulsified with S-T emulsifier and determined by ultraviolet spectrophotometry. Under normal temperature, the oil even dispersed in sewage with S-T emulsifier. It is stable and direct determined without separation. The oil is from sewage. The linear range is 0-92 micrograms.mL-1, and rate of recovery is 89%-129%. The method is quick and simple.

Animals↗
PubMed2001

[Determination of Vc with phosphomolybdate-blue spectrophotometry].

According as that Vc can reduce phosphomolybdate ammonium quantitatively to blue substance on certain conditions, a new spectrophotometry determinting Vc is proposed in this paper. On the conditions selected in this paper, the maximum absorptive wavelength of phosphomolybdate-blue formed by the reaction of ammonium phosphomolybdate with Vc is at 700.1 nm. It does not form moly-blue (650 nm) when excessive ammonium phosphomolybdate react with trace Vc. The conditions of determination is easy to control. This method can determinate Vc in food, medicine easily and conveniently. The accuracy and the repeatability are satisfactory.

Ascorbic Acid↗
PubMed2000

[Nickel cation biosorping studies by yeast with dimethylglyoxime spectrophotometry].

The beer yeast as the biosorbent of Ni2+ is studied. Nickel cation was determined by dimethylglyoxime spectrophotometry. The adsorbed quantity is larger at pH = 6. The equilibrium time was 60 minutes. Salinity and Ca2+, Mg2+ have no significant effect on the biomaterial uptake. Higher the equilibrium concentration(c) is, larger the adsorbed quantity(q) of yeast is. In addition, relations between c and q were fitted with followed equations: 1/q = 0.340 + 0.0753 x 1/c, r = 0.995; lgq = 3.989 + 0.789 lgc, r = 0.995. So we concluded that the models of adsorption are fitted with Langmuir and Freundlich isotherm adsorption equation.

Adsorption↗
PubMed2000

[Simultaneous determination of La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+ in their mixtures by multi-system multi-wavelength computational spectrophotometry].

Since the spectra of the rare earth color complexes are rather similar, it is very difficult to determine simultaneously rare earth elements in their mixtures. To reduce the collinearity of multicomponent spectra, different amounts of EDTA-Na2P2O7 were added to the rare earth-DBC-CPA(2-(4-chloro-2-phosphonophenylazo)-(2,6-dibromo-4- chlorophenylazo) 1,8-dihydroxy-3,6-naphthalene-difulfonic acid) color system. The flexible tolerance method which has high numerical stability and resolving power was used to improve the reliability of simultaneous spectrophotometry. The method has been applied to simultaneous spectrophotometric determination of seven components of rare earth elements(La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+) in synthetic samples with satisfactory results.

Cerium↗
PubMed2001

[Simultaneous determination of trace cadmium and arsenic in grains using atomic absorption spectrophotometry].

Simultaneous determination of two components in single wavelength using interferencing effect and atomic absorption spectrophotometry assisted by simulated annealing-back propagation of error-artificial neural networks algorithm was realized, and simultaneous determination of trace cadmium and arsenic in grains was studied. The results obtained are satisfactory. The recoveries found by standard addition method are 91%-98% and 87%-92% respectively. Relative standard deviations for 7 times of determinations are all less than 4%. This method is fast and simple.

Arsenic↗
PubMed2001

[Analysis of the content of ten kinds of metal elements in cerebrolysin by atomic absorption spectrophotometry].

The contents of Mg, K, Ca, Cr, Mn, Fe, Co, Ni, Cu and Zn in eight different brand cerbrolysins were determined by flame atomic absorption spectrophotometry. The statistical results as follows: the metal elements have significant difference between in seven kinds of Chinese products and in the cerebrolysin made by Austria. According to the results, we studied the inter relation of metal elements with medicine result, and analyzed the effect of trace elements in cerebrolysin. It provided useful data for medicine on clinical practice.

Amino Acids↗
PubMed2000

[Determination of eight trace elements in kadsura coccinea by flame atomic absorption spectrophotometry].

In this paper, we used the flame atomic absorption spectrophotometry to determine the contents of Zn, Fe, Ca, Cu, K, Na, Mn, Mg in the kadsura coccinea. We assayed the determination conditions systematically. The SrCl2 was sued to eliminate coexisting elements. And we achieved the purpose that we can determine a lot of elements in the same liquor at the same time. It shows that this method is simple, convenient and accurate.

Calcium↗
PubMed2000

[Determination of palladium by ion exchange resin phase spectrophotometry].

A new method for the determination of palladium by ion exchange resin phase spectrophotometry has been established. It is based on the fixation of palladium as 1-(5-bromo-2-phridylazo)-2-naphthol-6-sulphonic acid (5-Br-PAN-S) compelled on a anion-exchange resin. The resin phase absorbances at 690 and 800 nm are measured directly and the linear range of 0-20 micrograms for palladium. The method has been applied to the determination of palladium in water samples and catalysts with satisfactory results.

Ion Exchange Resins↗
PubMed2000

[The determination of Niphensamide by UV spectrophotometry].

In this paper Uv spectrophotometry was used to determine Niphensamide. In this method, 372 +/- 1 nm was selected as a criterion for quantitative determination, and the absorptivity. E1 cm 1% = 556. The results indicated that a better linear-relationship between the absorbance and the concentration of the sample. When the concentration was ranged from 0.5 mg.L-1 to 40 mg.L-1, the correlation coefficient was 0.9999, and the mean rate of recovery reached 99.8%.

Molluscacides↗
PubMed2003

[Synthesis of azobenzol compound and analytical application in a new catalytic spectrophotometry system].

Analysis of the indicator synthesis was studied by catalytic spectrophotometry, and the reducing decolorization that the copper(II) catalyzed the ration between ascorbic acid and 3-methyl-4-amino-4'-nitro azobenzol was discussed. Reaction condition was optimized and a highly selective determination of trace copper(II) was established. The detection limit was 0.048 microgram.L-1 for copper (II). The method has been used for determining trace copper(II) in human hair and aluminum alloy samples with satisfactory results.

Ascorbic Acid↗
PubMed2000

[Determination of trace copper, zinc, iron, calcium and magnesium in lymph by flame atomic absorption spectrophotometry].

This paper reports the determination of trace Copper, Zinc, Iron, Calcium and Magnesium in lymph by flame atomic absorption spectrophotometry. The lymph samples were digested with HNO3-HClO4. The method is convenient and rapid. The rates of standard recovery of Copper, Zinc, Iron, Calcium and Magnesium were 99.2%, 103.0%, 102.0%, 104.0% and 98.5% respectively.

Calcium↗
PubMed2000

[Determination of trace Cr in medical material progesterone by flame atomic absorption spectrophotometry].

This paper report the development of the determination of trace metal Cr in medical material progesterone by flame atomic absorption spectrophotometry. After the organic compounds are eliminated by HNO3-H2O4 to decomposite completely, the sample is determinated by FAAS. The method is convenient and the results show good precision and accuracy. The relative standard deviation was 3.0% and the rate of recovery was 98.8%.

Chromium↗
PubMed2000

[Determination of trace amounts of nitrite and reaction mechanism by triple-wavelength spectrophotometry].

A new method was proposed for the determination of nitrite ion by triple-wavelength spectrophotometry. This limits ranges of determination are 0-0.560 mg.L-1 nitrite ion at 599.1 nm, 420.6 nm and 283.4 nm. It has been applied to analysis trace amounts of nitrite ion of standard sample and environmental water with satisfactory result, the relative error was less 1.7% and recovery of the real samples was between 96.5 and 100.0%. This method is based on the diazotization-coupling react of thionine with nitrite ion in acidic medium, the mole ratio of thionine:nitrite is 2:1 by the continuous variation and mole ratio method.

Nitrites↗
PubMed1992

[Simultaneous analysis of vitamin B complex by least square UV-spectrophotometry].

Simultaneous analysis of VitB1, VitB2 and VitB3 in Vitamin B Complex tablets was made by least square UV-spectrophotometry. The results showed that the contents of VitB1, VitB2 and VitB3 could be calculated by computer with least square method using 12 absorbances of 239, 241, 257, 259, 261, 263, 266, 269, 270, 279 and 281 nm wavelengths. The reclamation of VitB1 was 101.4% (CV% = 0.88, n = 3), of VitB2 98.5% (CV = 0.43, n = 3), and of VitB3 101.3% (CV% = 0.15, n = 3).

Least-Squares Analysis↗