二维光学薄膜的气敏反射光谱特性

研究二维光学薄膜ＳｎＯ２：ＴｉＯ２在乙醇、丙酮、氨蒸汽中的气敏反射光谱，发现它与厚膜（膜厚２０μｍ）的气敏反射光谱有明显的差异，它的反射光强在气体浓度较低时随气体浓度增加而增强，气体浓度较高时则现象相反，并且它的反射峰会发生位移。利用不同气体的反射峰的气敏特性，可制成有气体选择性的气敏光纤传感器。     

α－甲基丙烯酸烯丙酯的合成及其自由基、阴离子聚合的研究

合成了α－甲基丙烯酸烯丙酯（ＡＭＡ），并对其自由基、阴离子聚合进行了探讨。结果发现，该单体难以进行选择性自由基聚合，但可用作多种单体自由基聚合的交联剂。用１，１′－二苯基己基锂在ＴＨＦ中引发ＡＭＡ，可顺利地进行α位双键的选择性阴离子聚合，分子量实测值与计算值基本一致。在较低温度下（≤－６０℃），可得窄分布ＰＡＭＡ（Ｍｗ／Ｍｎ＝１．１２～１．１５）。随聚合温度升高，间同和无规聚合物含量分别呈下降和上升趋势。ＧＰＣ、１ＨＮＭＲ及ＦＴＩＲ鉴定表明，用阴离子聚合法可得到溶于多种溶剂、每个重复单元上均定量带有烯丙基双键的窄分布官能性ＰＡＭＡ。     

含72元环的二维网状结构超分子配合物的合成与结构

用自组装方法合成具有特殊网状结构及光学、电学、磁学、离子或分子交换、催化等性能的化合物的分子工程学和超分子化学近年来成为人们研究的热点,并已取得了很大进展［１,２］．当前常用的一种三角架结构单元是刚性芳基三角架配体［３～５］,而对柔性芳基三角架配体及...     

Protective effect of total aralosides of Aralia elata (Miq) Seem (TASAES) against diabetic cardiomyopathy in rats during the early stage, and possible mechanisms

Total aralosides of Aralia elata (Miq) Seem (TASAES) from Chinese traditional herb Longya Aralia chinensis L was found to improve cardiac function. The present study was to determine the protective effects of TASAES on diabetic cardiomyopathy, and the possible mechanisms. Therefore, a single dose of streptozotocin was used to induce diabetes in Wister rats. Diabetic rats were immediately treated with low, medium and high doses of TASAES at 4.9, 9.8 mg/kg and 19.6 mg/kg body weight by gavage, respectively, for eight weeks. Cardiac function was evaluated by in situ hemodynamic measurements, and patch clamp for the L-type Ca²⁺ channel current (I_Ca²⁺-L) and transient outward K⁺ channel current (I_to). Histopathological changes were observed under light and electron microscope. The expression of pro-fibrotic factor, connective tissue growth factor (CTGF) was monitored using immunohistochemistry staining. Compared with diabetic group, medium and high doses, but not low dose, of TASAES showed a significant protection against diabetes-induced cardiac dysfunction, shown by increased absolute value of left ventricular systolic pressure (LVSP) and maximum rates of pressure development (±dp/dt_max), and enhanced amplitude of I_Ca²⁺-L (P < 0.05). Histological staining indicated a significant inhibition of diabetes-caused pathological changes and up-regulation of CTGF expression (P < 0.05). The results suggest that TASAES prevents diabetes-induced cardiac dysfunction and pathological damage through up-regulating I_Ca²⁺-L in cardiac cells and decreasing CTGF expression.     

Investigation of 500 keV Si ion induced surface structuring of Ni and Ti for enhancement of field emission properties

The present paper reports the investigation of surface morphology, elemental composition, phase changes and field emission properties of Si ion irradiated nickel (Ni) and titanium (Ti). The Ni and Ti targets have been irradiated with 500 keV Si ions generated by Pelletron accelerator at various fluences ranging from 6.9 × 10¹³ to 77.1 × 10¹³ ions/cm². Stopping range of ions in matter analysis revealed higher values of electronic stopping and sputtering yield for Ni as compared with Ti. For both irradiated metals, electronic energy loss dominant over the nuclear stopping. The growth of induced surface structures have been analysed by using field emission scanning electron microscopy (FESEM) analysis. In case of Ni, as the ion fluence increases from 6.9 × 10¹³ to 65.8 × 10¹³ ions/cm², the formation of spherical particulates, agglomers and sputtering is observed. Although in the case of Ti, with the increase of Si ion fluence from 11.6 × 10¹³ to 77.1 × 10¹³ ions/cm², the formation of irregular-shaped particulates along with crater and sputtered channels is observed. X-ray diffraction (XRD) analysis shows that no new phase is identified. However, a significant increase in peak intensity is observed with increasing ion fluence. The variation in crystallite size and dislocation line density is also observed as a function of Si ion fluence. Fourier transform infrared spectroscopy analysis shows that no bands are formed after the Si ion irradiation. Field emission properties of ion-structured Ni and Ti are well correlated with the growth of surface structures observed by SEM and dislocation line density evaluated by XRD analysis.