Showing papers on "Sodium dichromate published in 1994"

Renal failure and nephrotoxic drug-induced disturbances in rat kidney tissue

Abstract: The injection to rats of glycerol, cisplatin, uranyl acetate, sodium dichromate, and mercuric chloride is followed on the third day by acute renal failure. A new approach for quantitative estimation of disturbance of excretory renal function is presented. The decrease in renal function due to uranyl acetate was 77%; sodium dichromate, 71%; mercuric chloride, 52%; cisplatin, 25%; and glycerol, 10%. The kidneys still maintained serum ion concentration close to normal values. Injection of nephrotoxic drugs increased kidney wet weight by 24-57%. This was caused by swelling of renal tissue and increases in dry weight of the kidneys. The sodium content increased in the renal cortex and decreased in the papilla. The potassium content of the renal cortex is increased. The effect of some nephrotoxic drugs is suggested to depend on an increased number of cells in the renal cortex (probably due to hemostasis and inflammation) and a decrease of renal medulla function. The above drugs induce disturbance of kidney tissue but have no effect on the ion and water content in liver and m. gastrocnemius.

Production of sodium dichromate from chromite

Abstract: An iron/chromium alloy, which may be produced by reduction of chromite ore, is reacted with oxygen to form a ferrochromium melt and a Cr2O3-containing slag, and the slag is digested with alkali (eg Na2CO3) and an oxidizing agent (eg O2) to produce sodium chromate which may be converted to sodium dichromate.

Passivate for tungsten alloy electro-plating

Abstract: PROBLEM TO BE SOLVED: To improve corrosion and deterioration resistances by bringing a tungsten alloy electroplate into contact with a specified amount of CrO 3 in an aq. soln. in a bath having a specified pH to passivate the tungsten alloy electroplate. SOLUTION: A tungsten alloy electroplate is brought into contact with CrO 3 in an amount effective for passivation such as about 1.8 - about 45 g/liter in a bath having a definite parameter, pH of about 3.5 - about 8. At this time, a bath temp is preferably about 38 - about 82°C. As an origin of CrO 3 , there may be cited chromic acid, potassium dichromate, sodium dichromate, sodium chromate, potassium chromate and their mixtures. Control of pH in the bath can be carried out by adding a hydroxyl ion origin, sodium hydroxide, ammonium hydroxide, carbonate and their mixtures. COPYRIGHT: (C)1996,JPO

Study on the structure of fulvic acid from weathered coal using modified sodium dichromate oxidation and gc-ms

Abstract: The fulvic acid extracted from a weathered coal (Tulufan, Xinjian, China) was methylated, and then oxidatively degraded with sodium dichromate (Na2Cr2O7) in water at 210°C. The degradation products isolated from the aqueous solution were analyzed using capillary gas chromatography-mass spectroscopy (GC-MS) after esterification. Thirty seven compounds were structurally identified from the degradation products. They were: (1) benzenecarboxylic, phenolic and methylbenzenecarboxylic acids, (2) naphthalenecarboxylic acids, (3) pyridinecarboxylic acids, and (4) aliphatic acids. The pyridine structures have never been reported in the relevant literatures.

Field screening for hexavalent chromium in soil: A fast-turnaround field method based on water extraction

Abstract: Sodium dichromate has been identified as a contaminant of concern at several waste sites on the Hanford Site. Although chromium standards for soil are typically stated in terms of total chrome, much of the toxicity and carcinogenicity are attributed to the hexavalent state, which typically exists as a relatively mobile anion. Investigation and removal of crushed drums potentially containing residual sodium dichromate required a field test for hexavalent chromium to support characterization and remediation activities. Previous experience with a commercially available field test kit had been unsuccessful. This stimulated an effort to determine potential sources of error in the field test and led to a number of modifications that significantly improved the reliability of the test.