in many processes polymeric foams can be produced by using chemical or physical blowing agents. in this work for polyethylene foam production, the chemical blowing agents and compression moulding process were employed. at first, by using dsc diagram of two polyethylene grades, a suitable polyethylene grade was selected for foam production and then we discuss about blowing agent critical percent...

the seasonal diversity and distribution of microphytes and macrophytes in 40 artificial irrigationponds constructed in a semi-arid region, and the most suitable conditions to maintain these enclaves asbiodiversity spots were studied for the first time. a total of 104 species were detected. bacillariophyta,cyanobacteria and chlorophyta dominated both pelagic and benthic microphytic communities, ...

The sensitivity of non-replicating McCoy cells pretreated with polyethylene glycol for the isolation of Chlamydia trachomatis from clinical specimens and for the growth of a laboratory strain was compared with the sensitivity of untreated non-replicating cell cultures. The concentration of polyethylene glycol in different solutions and the time of addition to the cell culture medium were critic...

in this article, a complete model for the mixed flow slurry reactor for polymerization of ethylene to high density polyethylene in the presence of ziegler-natta catalyst is presented. in addition to the effects of the multiple active sites, the effect of other important parameters such as the catalyst concentration, co-catalyst, hydrogen, monomer, impurities and pressure on the mass-average and...

Introduction. A new technique of implantation of high-density porous polyethylene nasal dorsal implants in Asians is described in this paper. Silicone sizers, which have smooth surfaces, were used to facilitate implantation of porous polyethylene implants in Asian patients. Materials and Methods. Twenty-three patients of Asian descent underwent dorsal augmentation rhinoplasty with open techniqu...

An enhanced dielectric permittivity of polyethylene and related polymers, while not overly sacrificing their excellent insulating properties, is highly desirable for various electrical energy storage applications. In this computational study, we use density functional theory (DFT) in combination with modified group additivity based high throughput techniques to identify promising chemical motif...

0