heterogeneous proton exchange membranes (pem) are synthesized using the dry phase inversion technique. the casting solutions are prepared by dispersing a finely ground cation exchange resin particle in n,n-dimethylacetamide (dmac) solution of polyvinyl-chloride (pvc). results show that ion exchange capacity is increased with the addition of 1 %-wt nanosilica (from 0.14 to 0.27 meq/g) while it i...

This paper describes a model of knowledge-based system for integrating CAM and CNC operations. In detail, the main concern of integration is driven by proposed standardized check list as a part of product data which is useful for capturing and managing the knowledge based activities done by CAM operators and CNC machine operators in assessing product data before proceeded into CNC machining pro...

in this work a new resistance model has been presented based on that of henis-tripodi which can be used for interpretation of gas permeation data in composite and asymmetric membranes. in contrast to the previous works, in this model the fraction of the support layer surface that includes the pores filled with coating material has been taken into account. the influences of the filled pores on s...

Silver-impregnated membrane was facilely prepared by ex situ silver nanoparticles (NPs) blending method using polyethersulfone (PES) as the base polymer. A total of three membranes [F1(S0), F2(S0.5) and F3(S2.0)] were fabricated at different weight percentages of polymer and silver (Ag) loadings to compare their effects on membrane morphological and performance properties. All membrane types we...

Adding antioxidants to semen extenders could reduce post-thaw sperm damages. Glutathione is an important intracellular antioxidant that has free radicals scavenging properties and multiple effects on DNA and protein synthesis. In the present study, effects different levels of reduced glutathione (GSH) containing 0 (control), 1.0, 2.5, or 5.0 mM in a nanomicelle-based extender on post-thaw quali...

Background and Objectives: One of the problems in juice membrane clarification is the accumulation and deposition of rejected compounds on membrane surfaces or inside its pores which results in a membrane fouling. Materials and Methods: Several parameters can have influence on fouling in one hand and prediction of juice permeates flux during the membrane processing is of importance in indust...

the responses of yield and yield components of 24 advanced bread wheat genotypes to pre- and post-anthesis drought stress conditions were studied at ardabil agricultural re-search station during the 1997-2000 cropping seasons. results showed that genotypes produced significantly lower spikes no./m2, seeds no./spike and grain yield under pre- than in post-anthesis drought stress conditions. howe...

to obtain drugs which are more selective at benzodiazepine (bzd) receptors, design and synthesis of functionally selective ligands for bzd receptors is the current strategy of our pharmaceutical chemistry department. the affinity of newly synthesized ligands is assessed by radioligand receptor binding assays. based on our previous studies, 2-phenyl-5-oxo-7-methyl-1,3,4-oxadiazolo[a,2,3]-pyrimid...

Sol-gel and polymeric membrane electrodes, based on thiacalix[4]arene as a neutral carrier, weresuccessfully developed for the detection of VO2+ in aqueous solutions. The sol-gel and PVCmembrane electrodes exhibited linear response with Nernstian slopes of 29.3 and 28.4 mV perdecade, respectively, within the vanadyl ion concentration ranges from 1.0 × 10-6 to 1.0 × 10-1mol dm-3 and from 1.0 × 1...