The polymer-polymer interaction parameters of STVPh/PPC blends were calculated by Hildebrand solubility parameter. Accordingly the miscibility of the blends was predicted. The segment motion and miscibility of blends ...The polymer-polymer interaction parameters of STVPh/PPC blends were calculated by Hildebrand solubility parameter. Accordingly the miscibility of the blends was predicted. The segment motion and miscibility of blends were also investigated by electron spin resonance(ESR) spin probe method. ESR spectra were measured as a function of temperature and the hydroxyl content in STVPh. For all blends, two spectral components with different rates of motion, a "fast" and a "slow" component were observed. This result showed that the nitrooxide radical existed in two different matrixes, a more flexible PPC-rich and a more rigid STVPh-rich micro domain. In addition, T 5mT and rotational correlation time τ c and activation energy E a were obtained from ESR spectra, which indicated the hydrogen bonding between the carbonyl and ether oxygen in PPC and the hydroxyl in STVPh was enhanced with increasing the hydroxyl content in STVPh.展开更多
NITRIC oxide (NO) is the important cell messenger molecule that regulates the central ner-vous, cardiovascular, endocrine and immunity systems. The study of NO not only canexplain many physiological phenomena, but als...NITRIC oxide (NO) is the important cell messenger molecule that regulates the central ner-vous, cardiovascular, endocrine and immunity systems. The study of NO not only canexplain many physiological phenomena, but also can provide new ways to prevent and treat alot of diseases. However, at present, most of the methods for assaying NO produced by or-ganism have some defects, for example, low sensitivity, no specificity, no convenience.展开更多
文摘The polymer-polymer interaction parameters of STVPh/PPC blends were calculated by Hildebrand solubility parameter. Accordingly the miscibility of the blends was predicted. The segment motion and miscibility of blends were also investigated by electron spin resonance(ESR) spin probe method. ESR spectra were measured as a function of temperature and the hydroxyl content in STVPh. For all blends, two spectral components with different rates of motion, a "fast" and a "slow" component were observed. This result showed that the nitrooxide radical existed in two different matrixes, a more flexible PPC-rich and a more rigid STVPh-rich micro domain. In addition, T 5mT and rotational correlation time τ c and activation energy E a were obtained from ESR spectra, which indicated the hydrogen bonding between the carbonyl and ether oxygen in PPC and the hydroxyl in STVPh was enhanced with increasing the hydroxyl content in STVPh.
文摘NITRIC oxide (NO) is the important cell messenger molecule that regulates the central ner-vous, cardiovascular, endocrine and immunity systems. The study of NO not only canexplain many physiological phenomena, but also can provide new ways to prevent and treat alot of diseases. However, at present, most of the methods for assaying NO produced by or-ganism have some defects, for example, low sensitivity, no specificity, no convenience.
