a proton nmr method for the drtermination of salvation numbers of alkaline earth cations with hexamethyl phosphoramide (hmpa) in nitromethane (nm) as diluents is described. the method is based on monitoring the resonance frequency of hmpa protons as a function of hmpa / metal ion molar ratio at constant metalion concentration. the average salvation number of cations,  , at any hmpa / metal ion ...

The metal-assisted chemical etching (MACE) was used to synthesis silicon nanowires. The effect of etchant concentration, etching and chemical plating time and doping density on silicon nanowires length were investigated. It is held that the increasing of HF and H2O2 concentrations lead to etching rate increment and formation of wire-like structure. The results show that, the appropriate ratio o...

introduction: almond (prunus amygdalus b.) is one of the most important crops consumed as a dry fruit and it is mainly adaptable to arid and semi-arid regions mostly suffering from salinity stress (8). soils with dry humidity regime are dominant in iran and in the world at large and mostly include regions with more evaporation than precipitation. this in turn leads to increased salinity of the ...

preparation of tretinoin-containing microspheres with the aim of reducing undesirable skin reactions towards trans retinoic acid (tra) and thus, improving patient compliance is of particular interest. these microspheres have to be smaller than 30 m m to avoid causing gritty feel when applying on the skin, and slow the release of drug to minimize its skin side effects. following preliminary eval...

The development and design of the biocompatible and biodegradable thermodynamically stable micellar and microemulsion transparent dispersions to reduce the free and unbounded drugs concentration in the blood is a basic challenge in field of drug efficacy and bioavailability of drugs. In the current work, solubilization capacity of the drug (Tocopherol), oil (Ethyl Butyrate), and oil+drug (1:1 m...