The use of the electrostatic classification method for sizing monodisperse 0.1 μm polystyrene latex (PSL) spheres has been investigated experimentally. The objective was to determine the feasibility of using electrostatic classification as a standard method of particle sizing in the development of a 0.1 μm particle diameter Standard Reference Material (SRM). The mean particle diameter was calcu...

Abstract We use the geometric mean to parametrize metrics in Hassan–Rosen ghost-free bimetric theory and pose initial-value problem. The of two positive definite symmetric matrices is a well-established mathematical notion which can be under certain conditions extended quadratic forms having Lorentzian signature, say g f . In such case, null cone metric h middle cones appearing as average space...

Several studies have been performed to evaluate the desertification in Iran andother countries which led to present national and regional models. One of them is IMDPAmodel. This model was used as a case study in Taraz Nahid, Saveh, Iran. In this study, fivefactors including climate, soil, vegetation, irrigation, and socioeconomic ones wereevaluated. According to the region conditions for each c...

A multiple-unit oral floating system was prepared using the emulsification-solvent diffusion method to prolong the gastric emptying time of theophylline. For this purpose, theophylline, ethyl cellulose and dibutyl phthalate were dissolved in an ethanol/dichloromethane mixture, added to 0.1 M HCl containing NaCl (20%) or saturated theophylline and/or different concentrations of polysorbate 80 an...

Sustainable forest production requires an understanding of the effects of site disturbance on tree growth and the consequences of soil amelioration and vegetation control practices. We assessed the impacts of biomass removals at harvest, soil compaction and tillage, and vegetation control on early growth of Douglas-fir in coastal Washington. Harvest treatments included removal of commercial bol...