results the mean kt/v was 1.27 ± 0.28 in high-flux and 1.10 ± 0.32 in low-flux membrane which, these differences were statistically significant (p = 0.017). the mean of urr was 0.65 ± 0.09 in high-flux and 0.61 ± 0.14 in low-flux membrane, which these differences were not statistically significant (p = 0.221). patients and methods forty hemodialysis patients participated in this cross-over clin...

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...

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...

Modulation of small tunneling barriers by thermally activated voltage fluctuations is observed in the composite material carbon polyvinylchloride consisting of large conducting carbon chains and aggregates separated by narrow insulating gaps. The eA'ect is experimentally determined by applying an ac stress to the sample and measuring the change in resistivity per unit strain as a function of te...

We have used liquid exfoliation of hexagonal Boron-Nitride (BN) to prepare composites of BN nanosheets of three different sizes in polyvinylchloride matrices. These composites show low levels of reinforcement, consistent with poor alignment of the nanosheets as-described by a modified version of Halpin-Tsai theory. However, drawing of the composites to 300% strain results in a considerable incr...

We study the mutual interactions of simple parallel polymers within the framework of density-functional theory (DFT). As the conventional implementations of DFT do not treat the long-range dispersion [van der Waals (vdW)] interactions, we develop a systematic correction scheme for the nonlocal energy contribution of the polymer interaction at the intermediate to the asymptotic separations. We p...

The results of a cancer mortality study among workers employed in the production of vinylchloride and polyvinylchloride between 1939 and 1977 suggest a significant increase in deaths from malignancies of the lymphatic and haemopoietic tissues. Mortality for tumours of the digestive organs, respiratory system, bone and connective tissues, brain, and skin are also greater than in the general popu...

Combining photolithography and hot embossing offers the capability of cost-efficient and high-fidelity fabrication of polymer microfluidic devices, however, poor chemical resistance in nonpolar organic solvents and high gas permeability of the currently used polymers narrow the range of applications of the microfluidic devices. With the aim of specific chemical or biological applications, we re...