Transport of K in PVC matrix membranes containing valinomycin

We report impedance measurements on PVC matrix membranes which contain KBPh₄ with varying proportions of valinomycin. In agreement with our earlier measurements the value of the bulk membrane resistance (R_b) is much larger in the presence of valinomycin, indicating that the mobility of K⁺ is greatly reduced by the valinomycin. R_b shows a linear variation with valinomycin/K⁺ ratio between 0 and 1, but it is invariant at higher valinomycin/K⁺ ratios. Thus there is no evidence for a special transport mechanism for K⁺ in these membranes.     

汽车电子系统要求低静态电流

如今的汽车电子系统越来越复杂。同时，汽车环境对任何电子产品来说都是很大的挑战，因为汽车电子系统要求运行电压很宽，并且有很大的瞬态电压和温度变化。另外，性能要求也越来越高，需要多个供应电压以满足系统的不同要求。典型的     

Apoptosis in the rostral migratory stream of the developing rat

The rostral migratory stream consists of a large number of cells migrating from the lateral ventricles to the rostral telencephalon, primarily the olfactory bulb. The pathway continually provides neuro- and glioblasts throughout life. The present paper indicates that a considerable number of cells undergo apoptotic cell death en route, even in young (day 3) rats when presumably many vacant sites are still available in the developing brain.     

PMMA tacticity and alumina powder dispersion stability

Summary Sedimentation experiments and X-ray photoelectron spectroscopy (XPS or ESCA) analyses have been used to study the effect of poly(methylmethacrylate) (PMMA) tacticity on aluminum oxide powder dispersion stability in a common solvent medium. The relative trends from sedimentation densities, and from surface analyses after solvent washing show that (PMMA) adsorption is greatest with isotactic polymer, where isotactic>atactic>syndiotactic adsorption. These results suggest that surface adsorption and hence dispersion stability can be influenced by polymer chain configuration as well as by chain conformation.