A series of natural rhyolitic obsidians were analyzed for their total water contents by a vacuum extraction technique. The grain size of the crushed samples can significantly affect these analyses. Coarse powders must be used in order to avoid surface-correlated water. These analyses were used to calibrate infrared spectroscopic measurements of water in glass using several infrared and near-inf...

Background: There are great resources of natural zeolite in Iran. Zeolite, an inorganic ion-exchanger, may be used as a suitable technical-economical solution for water treatment in many regions of Iran. In this study, the characterization of natural zeolite natrolite and the feasibility of removing hardness, cations, and anions were investigated. Methods: First, zeolite composition and type...

Sawdust which is the main waste from wood industry has been used as a raw material forremoval of Brilliant Cresyl Blue toxic dye. The effects of various parameters such as pH,electrolyte concentration, adsorbent dose, contact time and agitation rate were studied for theremoval of the dye in a concentration of 50 mg L-1. The optimum condition for the studiedparameters was applied for various con...

aims: arsenic contamination of natural water resources has become an important environmental problem in the world. the adsorption method by iron filings adsorbent or zero-valent iron was used. the study aimed to evaluate the efficiency of iron filings in arsenite removal from polluted water and to investigate the effect of magnetic field on the process. materials & methods: this interventional ...

An on-column enrichment method was developed for the rapid determination of inorganic anions in natural water. The system was assembled from a syringe pump, a six-port switching valve with a sample-enrichment loop, a separation column and a UV detector. The enrichment efficiency of the system was tested by using inorganic anions as samples. The limits of detection were between 0.6 and 7.7 micro...

BACKGROUND & OBJECTIVE Hepatitis A is an enterically transmitted viral disease, highly prevalent in India and mainly presents as a paediatric sporadic disease. This study investigated an outbreak of viral hepatitis at Shimla, Himachal Pradesh, India, during January-March 2007. METHODS Eighty seven blood samples, 3 water samples and 2 sewage samples were collected. Serum samples were tested fo...

background: there are great resources of natural zeolite in iran. zeolite, an inorganic ion-exchanger, may be used as a suitable technical-economical solution for water treatment in many regions of iran. in this study, the characterization of natural zeolite natrolite and the feasibility of removing hardness, cations, and anions were investigated. methods: first, zeolite composition and type we...

the capacity of natural zeolites to absorb anionic pollutants from water is limited. this limitation can be overcome by modifying the surface of the minerals with organic cations. in this research, natural zeolite, analcime was used for removing the nitrate and nitrite impurities from aqueous solutions. the surface of the zeolite was modified by tetramethylammonium and tetraethylammonium ions t...

The effects of calcium, cupric, ferrous and ferric ions on the formation of trihalomethanes (THMs) and haloacetic acids (HAAs) were investigated using natural organic matter (NOM), small molecular weight NOM surrogates and natural water samples. The results showed that the effects were greatly dependent on the disinfection byproduct (DBP) precursor structure and molecular weight, and metal ions...

Phosphatase activities (cell-bounded phosphatases "BP" and freely dissolved phosphatases "D P") in water samples from a natural lake "Laguna Grande" (Antequera, Málaga, Spain) amended with 50 microg/ml of selected insecticides, herbicides and fungicide captan were studied under laboratory controlled conditions (temperature and agitation). Our data show that dissolved alkaline phosphatase was th...