Particles of ZnO coated with carbon (ZnOCC) were prepared and evaluated for their antibacterial activity. ZnO powder and poly(vinyl alcohol) (PVA) (polymerization degree: 2,000-95,000) were mixed at a mass ratio (ZnO/PVA) of 1, and then heated at 500-650 degree C for 3 h under argon gas with a flow rate of 50ml/min. Carbon deposited on the ZnOCC surface was amorphous as revealed by X-ray diffra...

Ion chromatography (IC), developed by Small et al. [1], is widely recognized as a simple and powerful analytical technique for the determination of various inorganic and organic anions and cations [2]. Sulfonated and carboxylated polymer resins and silicas are commonly employed as cation−exchange stationary phases in IC for cationic species. The application of unmodified silica gels as cation−e...

Macrocycle-based ion chromatography provides a convenient, reliable method for the determination of perchlorate ion, which is currently of great interest to the environmental community. This study shows that effective perchlorate determinations can be made using standard conductimetric detection by combining an 18-crown-6-based mobile phase with an underivatized reversed-phase mobile phase ion ...

AIM The aim of this study was to compare the neutralizing effect of antioxidant agents on the microleakage of dental restorations in nonvital teeth after bleaching with carbamide peroxide. Also assessed was the correlation of the microleakage data between an electrochemical and a staining technique. METHODS AND MATERIALS Following root canal therapy, 40 sound and similar human maxillary centr...

Cultivation machinery applies large amounts of mechanical energy to the soil and often brings about a decrease in soil organic carbon (SOC). New experiments on the effects of mechanical energy inputs on soil respiration are reported and the results discussed. In the laboratory, a speci®c energy, K, of 150 J kgÿ1, similar to that experienced during typical cultivation operations, was applied to ...