Leather processing is an important industry in China, and the discharge of chromium waste has been severely circumscribed. Though traditional processes for treating chromium waste have been widely used in tannery plants, technology adopting high efficiency and economic simultaneously is deficient. In order to develop an economic treatment for tannery waste, a mixed alkali of sodium hydroxide an...

Studies conducted in China linked selenium deficiency to higher risk of esophageal squamous cell carcinoma (ESCC), but this has not been widely tested outside that selenium-deficient region. The aim of this study was to investigate the association between selenium and other mineral concentrations in toenails and risk of ESCC in a region with high incidence rates. In this nested case-control stu...

Chromium (VI) Considered as a serious health hazard and it has attracted attention as a pollutant in natural waters. The sources of contamination of chromium in natural waters and in the Environment are from electroplating, tanning industries and waste solution from oxidative dyeing and leaching from sanitary land – fills, In view of this the separation and determination of chromium has been re...

Disclosed is a method of preparing pigmentary chromium oxide nano particles having 50 percent particle size less than about 100 nm. Preparation of nano chromium (III) oxide is investigated by thermal decomposition method. According to the disclosed method, a substantially dry solid composition of potassium dichromate and carbon active is heated in CO2 atmosphere to a temperature of about 60...

in this study, taguchi experimental design has been used for the optimization of thickness of chromium layers. for this purpose brass materials have been electroplated under various conditions of the process. an orthogonal array (oa) was employed to analyze the effect of plating parameters on the characteristic of the thickness. variables which were considered for working were as following; amo...

The surface modification processes such as hard facing, case carburizing, thermal spraying, ion nitriding, tough nitriding, and others, are some of the important techniques being adopted for providing enhanced life for parts and components, in service. Among them, plasma spray and High Velocity Oxy Fuel (HVOF) spray coatings are popular and widely used. In this investigation, plasma & High Velo...

A great amount of heavy metals enter Pampulha Reservoir via it's main tributaries (Sarandi and Ressaca). Although no water quality classification has been carried out for these tributaries, the reservoir is expected to be in class 2 of the CONAMA-86 system. As part of a monitoring scheme of the Pampulha Watershed, heavy metals (Zn, Pb, Cd, Ni, Cu, Cr, Mn and Fe) were investigated in the water a...

Four chromium based oxo-trinuclear carboxylate complexes were prepared by reacting chromium(III) nitrate nonahydrate with acetic acid and substituted carboxylic acids. They were characterized using infrared spectroscopy (FT-IR). Chromium content of the complexes was determined by titrimetry method. The chromium(III) monochloroacetate complex, [Cr3O(ClCH2COO)6.3H2O]NO3.3H2O in combination with d...

Under ultrasonic irradiation, organic fluorescence nanoparticles have been prepared by a reprecipitation method. Compared with single organic fluorophores, these nanoparticles are brighter, more stable against photobleaching and more water-soluble. They also have high room-temperature fluorescence quantum yields (approximately 20%) and a long fluorescence lifetime (approximately 0.2 micros). Ba...