丝素肽和β-环糊精包合作用及表面活性剂影响

在pH为2和包合时间是60min的最佳条件下,采用光谱法（荧光光谱与紫外-可见光谱）测得β-环糊精（β-CD）与丝素肽构成的包合体系包合比均是2∶1,平均包合常数是3.3×105。两种阴离子表面活性剂十二烷基硫酸钠、十二烷基苯磺酸钠对包合体系有阻抑作用,阳离子表面活性剂十六烷基三甲基溴化铵和非离子表面活性剂＂平平加O＂对包合体系没有影响。     

Iodine-mediated one-pot synthesis of C-3 acylated indolizines from pyridines,aryl methyl ketones and acrylate derivatives

An I₂/CuI-promoted multi-component reaction from pyridines, aryl methyl ketones and electron deficient acrylates has been accomplished in a “one-pot” manner, which provides a straightforward and efficient access to C-3 acylated indolizines. The key intermediate of N-ylides is hypothesized to be generated in situ from pyridines and (hetero)aryl methyl ketones in the presence of iodine. This method has been applied in the synthesis of two molecules with anticonvulsant and anti-inflammatory activities.     

丝素改性聚乳酸-羟基乙酸共聚物多孔微球作为牙龈间充质干细胞递送载体的研究

利用复乳-溶剂挥发法合成适合细胞三维培养的聚乳酸-羟基乙酸共聚物(PLGA)多孔微球, 并对其表面进行丝素改性, 利用扫描电子显微镜、 能谱、 红外光谱和X射线衍射等对改性前后PLGA多孔微球的理化特性进行表征. 原代培养人牙龈间充质干细胞并进行成骨(茜素红染色)成脂(油红O染色)分化鉴定. 通过负压混悬法将牙龈干细胞负载于丝素改性的PLGA多孔微球上进行5-乙炔基-2'-脱氧尿嘧啶核苷(EdU)细胞增殖及成骨分化研究. 结果表明, 原代培养的牙龈干细胞具有多向分化潜能, 负载在丝素改性的PLGA多孔微球上的细胞有利于细胞增殖. 丝素改性的PLGA多孔微球是良好的细胞递送载体, 为进一步修复牙槽骨缺损提供了科学依据.     

膨化柞蚕丝内部形态和结构的研究

利用扫描电镜(SEM), 结合拉曼(Raman)光谱、 衰减全反射傅里叶变换红外(ATR-FTIR)光谱和X射线衍射(XRD)等方法研究了膨化型柞蚕丝的内部形态和结构, 表征了其热性能和力学性能. 结果表明, 虽然经过了相应的膨化处理, 柞蚕丝素蛋白分子链仍表现出具有高度取向的反平行β-折叠构象, 而其单丝是由许多带状微纤沿纤维轴平行组装而成, 且具有较高力学性能的纤维.     

Cu(Ⅱ)-家蚕丝素蛋白质配合物的配位结构和高次结构

家蚕丝素蛋白质在不同pH条件下经均相和不均相配位反应制备了Cu(Ⅱ)-丝素配合物,用可见光谱、电子自旋共振波谱(ESR)、X射线衍射(XRD)研究了其配位结构和高次结构.在碱性条件下(pH=10.60),丝素肽链主链的4个氮原子螯合Cu(Ⅱ)生成具有近似平面四方Cu(N)₄结构的配合物;而在酸性条件下(pH=4.30,5.88),主要是丝素肽链的侧(端)基羧酸根键合Cu(Ⅱ)生成Cu(Ⅱ)(-COO-)(H₂O)₃和Cu(Ⅱ)(-COO-)₂型配合物.讨论和描述了不同条件下生成的Cu(Ⅱ)-丝素配合物的高次结构.     

天然蚕丝丝素蛋白的乳化活性

采用不同油相制备了系列丝素蛋白乳液, 研究了丝素蛋白浓度、 油相体积分数和油相极性对丝素蛋白的乳化活性指数、 丝素蛋白乳液的稳定性和类型及乳液液滴的微观形态、 粒径与zeta电位的影响, 探讨了丝素蛋白的乳化活性和乳液稳定机制. 结果表明, 丝素蛋白具有两亲性和表面活性, 可在油水界面富集并形成稳定的黏弹性保护膜; 丝素蛋白的乳化活性随其浓度的增大而减小, 随油相体积分数的增大而增大; 丝素蛋白浓度和油相体积分数的增加可提高稳定乳液体积分数.     

Advanced driver assistance system: Road sign identification using VIAPIX system and a correlation technique

We present a three-step approach based on the commercial VIAPIX® module for road traffic sign recognition and identification. Firstly, detection in a scene of all objects having characteristics of traffic signs is performed. This is followed by a first-level recognition based on correlation which consists in making a comparison between each detected object with a set of reference images of a database. Finally, a second level of identification allows us to confirm or correct the previous identification. In this study, we perform a correlation-based analysis by combining and adapting the Vander Lugt correlator with the nonlinear joint transformation correlator (JTC). Of particular significance, this approach permits to make a reliable decision on road traffic sign identification. We further discuss a robust scheme allowing us to track a detected road traffic sign in a video sequence for the purpose of increasing the decision performance of our system. This approach can have broad practical applications in the maintenance and rehabilitation of transportation infrastructure, or for drive assistance.     

Separation and quantitative determination of the cerium group lanthanides by gas-liquid chromatography

A gas chromatographic method is reported for the separation and subsequent quantitative determination of the cerium group lanthanides. The lanthanides (RE) are synergistically extracted from aqueous solution with the polyfluorinated beta-diketone 1,1,1,2,2,6,6,7,7,7-decafluoro-3,5-heptanedione, H(FHD), as ligand, and di-n-butylsulphoxide, DBSO, as neutral donor. The composition of the extracted species is reported to be RE(FHD)(3) .2DBSO. Thermogravimetric analysis of the complexes is reported. Analytical curves were prepared and found to be usable over the range of 0.1-10 mug of metal. Individual lanthanides were determined with 99.0 % recovery with a relative mean deviation of +/-2.0%. Mixture of lanthanides were analyzed with 101.2% recovery with a relative mean deviation of +/-2.2%.     

The Road Traffic Analysis Based on an Urban Traffic Model of the Circular Working Field

Under a relatively realistic model,this paper theoretically analyzes the road traffic status inside anurban working field,including its radial roads and circular ones.Concretely,the radial and the circular averagetraveling distances of a car commuter in a tiny ring with wide dx are first derived,and then the necessary roadarea,road area rate distributions,the proportion between the radial and the circular roads to be needed are alsocalculated.The results presented here and the properties shown through the numerical analysis are consideredto be significant at the very beginning stage of designing an urban city.