Effects of Porosity on Structure and Performance of PP Meshes for Reparing Pelvic Floor Defects

Currently, polypropylene （PP） synthetic mesh is a kind of common material used for pelvic floor＇s repairing and reconstruction. The repairing mesh is generally made with different hole shape and size. Porosity is one of the most important indicators of PP mesh. Two different-structure PP meshes are selected through adopting corresponding target density in the heat setting process for meshes owning different porosity. Then performance and structure of two kinds meshes with different porosity are tested. The results showed that： the increase of porosity leaded to the decreases of meshes＇ thickness, tensile strength and bursting strength. Meshes＇ bending stiffness was reduced and they became softer, but there was no significant change in suture pulling-out force, which maybe associated with the large aperture of PP meshes.     

Studies of the Rheological Behavior of Polypropylene/Polyamide-6 Blend by Capillary Rheometer

The theological behavior of blend, e. g. polypropylene, PP, with polyamide - 6, PA6, has been investigated. Results show that this blend is a pseudo plastic fluid and the amount of PA6 seems to be a dominator to influence all theological properties. In addition to the expected influence by temperature generally for polymer, it has been found the amount of PA6 is valid in a range, e. g. 0 - 20% corresponding to the PP amount, i. e. in this range, the larger the PA6 added, the larger is the non-Newtonian index, n, and this is obviously especially for PP/PA6 blend with the high shear stress.     

改性聚丙烯合成纸用涂覆液的研究

研制出一种用于PP（聚丙烯）合成纸的涂覆液，研究了CaCO3填料的含量、CPE的浓度、固化温度和固化时间对以该涂覆液粘接PP／PP的剪切强度的影响，结果表明，最大剪切强度可达0.728MPa，同时该涂覆液具有良好的耐老化性和贮存稳定性。以该涂覆液制备的合成纸书写性良好。     

多效唑在棉花滴灌上的应用效果研究

在膜下滴灌棉田，通过滴灌系统将多效唑ＰＰ３３３ 随水土施对棉花进行化学调控。研究表明，多效唑随水土施可有效地控制植株生长，矮化节间长度，增加单铃重，提高衣分率。施用多效唑可显著增加棉花产量，提高经济效益，与叶面喷施缩节胺相比，每公顷增产籽棉４４７ ．６ ｋｇ，增产率１０ ．３８ ％ ，每公顷净增收４６３ ．４ ～１ ６７０ ．９ 元     

浅谈聚丙烯的阻燃剂材料

简述了聚丙烯阻燃的研究进展和阻燃机理．指出了无卤、低烟、低毒的膨胀型阻燃剂、有机硅系阻燃剂以及纳米阻燃剂的开发与应用是当前的发展方向。     

水稻磷酸酯酶2A基因蛋白的原核表达载体构建、表达和纯化

利用PCR技术,从水稻品种日本晴幼穗cDNA中扩增磷酸酯酶2A的基因ORF片段,并将其克隆入原核表达载体pGEX-6p-1中构建重组质粒pGEX-6p-1-PP-2A,经限制性内切酶酶切鉴定以及测序结果表明成功构建了原核表达载体pGEX-6p-1-PP2A。转化E.coli JM109并通过终浓度为0．4mmol／L的IPTG诱导,表达出39kD的CST-PP2A融合蛋白,并用蛋白亲和层析柱GSTrap FF对表达产物进行纯化,为下一步的研究打下了实验基础。     

均匀设计在机械共混热塑性弹性体NBR/PP中的应用

利用均匀设计,结合DSC量热分析结果,寻找出NBR与PP机械共混合成热塑性弹性体的最佳条件和主要影响因素·通过扫描电镜分析NBR与PP的相容性,证实了上述结果·工业试验样品测试表明其具有高的拉伸强度和断裂伸长率,并具有较好的耐老化和耐油性能,其主要指标达到了国外同类产品水平     

Suppression of Cladding Mode Coupling by B/Ge Codoped Photosensitive Fiber With Photosensitive and Depressed Inner Cladding

Excess loss on the short wavelength side of the Bragg resonant wavelength caused by cladding mode coupling limits wide use of grating in the fiber communication system, especially in densed wavelength division multiplexing (DWDM) system.A novel photosensitive fiber design that have depressed cladding and photosensitive inner cladding in the same fiber is proposed, which can suppress cladding mode coupling greatly.Using MCVD method B/Ge codoped fiber with depressed cladding was fabriceted out, which was also doped in boron and germanium and had the photosensitivity.Finally, the transmission spectrum of written grating in this fiber by phase mask method verified its larger photosensitivity and greatly suppression of cladding mode coupling.     

PP平均绝对离差及其渐近性质

对两类较稳健的PP平均绝对离差M_1(a),M_2(a),(a∈S~(p-1))进行了讨论,获得了它们的渐近表示式,并由此得到M_1(a),M_2(a)关于a一致地渐近分布为高斯过程的上界.     

可环境消纳PP餐炊具的配方设计及综合环保效应研究

采用复合无机粉体为填充剂,以生物活性剂和稀土配合物复合体系光敏剂为混合表面处理剂,经挤出造粒制备可环境消纳聚丙烯(PP)母料;采用人工加速老化实验、户外曝晒实验、自然填埋实验,并用红外光谱、热重分析及ASTM试验等对可环境消纳PP餐炊具的综合环保效应进行较系统地研究,结果表明,可环境消纳PP餐炊具具有明显的光一生物降解性能,同时在焚烧处理时,可有效减少有害气体的产生量。