乌鲁木齐部分高架桥周围高层建筑不同层面CO和CO2的测定

伴随着经济的发展,日益急剧增加的机动车辆使高架道路经常堵塞从而也成为空中停车场.为了解决交通拥挤问题,乌鲁木齐市不断在建高架,但交通带来的环境问题日益突出,因此研究高架及周围建筑污染程度显得极为重要.本文研究了乌鲁木齐市高架交通污染物在周边高层不同层面一氧化碳和二氧化碳的分布规律,研究结果表明高架周围建筑不同层面的一氧化碳和二氧化碳的浓度分布具有一定规律.此项研究工作可以为乌鲁木齐高架道路建设和周边建筑物的合理规划布局提供参考.     

Morphological similarity of road networks and cracks

An investigation was made regarding to what extent road network patterns are reproduced by a crack model from a viewpoint that they seem to resemble crack patterns in morphology. A desiccation model using double-layered cellular meshes was considered with the parameters representing the anisotropy of the material and the coarseness of grains, together with the introduction of singularities in points and in lines. The model can generally reproduce the real crack patterns and the road network patterns of cities with characteristic morphology by appropriately choosing the values of parameters, indicating that the similar mechanism acts on the formation of road networks and cracks of material although the relevant scales of space time differ from each other. Factors which make the road networks more complex and irregular in morphology were also investigated.     

Patterned Peptide Multilayer Thin Films with Nanoscale Order Through Engineered Liquid Crystallinity

Self‐assembling polypeptide molecules have been designed to explore aspects of hierarchical or multiscale long‐range order, and the interactions that occur at various length scales that drive order and patterning in complex materials. Three peptides were synthesized with repetitive motifs loosely based on insect silks. Thin films were obtained from each peptide using a solvent templating technique. Smectic layers were observed in the thin films and in bulk materials prepared for comparison. A variety of additional effects, including chirality and interfacial anchoring at the helix, compete in the thin films, resulting in complex but regular patterns within the materials over a hierarchy of length scales spanning several orders of magnitude. The relative magnitude of these effects can be tuned through sequence design, as can the smectic layer thickness. Thus, many parameters describing the patterns in the materials can be controlled at the molecular design level, allowing complex patterns of nanoscale to microscale topography and chemistry to be created through self‐assembly. In addition to the potential for designer materials, there may be some biological relevance to the observed phenomena. The silk‐like molecules used fold into “hairpins,” providing a rigid unit that can drive liquid crystalline phase behavior. A similar process could be at work in silks and other structurally similar proteins that form textured materials. Chiral smectic order and multiscale patterns that can often result are clearly rich areas, worthy of further exploration.     

再生蚕丝的制备及其结构和性能初探

在制备高浓度高分子量蚕丝素蛋白水溶液的基础上, 采用湿法纺丝技术, 在一定条件下纺制出力学性能优于天然蚕(茧)丝的再生蚕丝纤维, 其断裂强度及断裂伸长率分别达到0.5 GPa和20%. 扫描电镜观察结果显示: 初生纤维具有典型的“皮芯”结构, 而纤维内部则为疏松多孔的网状或蜂窝状结构; 经过一定的后拉伸处理后, 纤维的表面变得光滑, 且内部结构也趋于致密. 固体 13C核磁共振及拉曼光谱分析结果表明, 后拉伸及热湿处理均有利于提高纤维内部β-折叠结构的含量, 分子链的规整度和取向性也随之改善, 从而使再生蚕丝纤维的力学性能得到进一步提高.     

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.     

有机相中蚕丝固定化脂肪酶催化酯化反应性能研究

研究了有机相中蚕丝固定化脂肪酶催化酶化反应的催化活性。考究了有机溶剂,底物、反应温度,ＰＨ值和体系含水量等因素对固定化脂肪酶催化活性的影响。结果表明,以异辛烷为有机溶剂,在反应温度为５０℃ＰＨ值为７．４时,酶催化活性最好。     

Electron binding energies in the study of adsorption by photoelectron spectroscopy: The reference level problem

There has been much discussion in the literature concerning the definition of a suitable reference level for electron binding energies in solids and adsorbed species. The reference level in molecular photoelectron spectroscopy is the vacuum level at infinity; and, in order to calculate the total energy of the system, it is also the appropriate reference level for electron binding energies in solids. We show that for solids and adsorbates the vacuum level is not a chemically useful reference level. This is because the absolute binding energy is affected by electrostatic potentials which are unrelated to the local chemical bonding. It is concluded that there is no experimental energy level, to which adsorbate binding energies can be referenced, which allows one to make an absolute measurement of binding energy shifts due to surface interaction. Approaches to obtaining chemically meaningful binding energies from the photoelectron spectra of adsorbates are discussed.     

新疆家蚕抗菌肽(Cecropin-XJ)毕赤酵母高密度发酵条件的研究

新疆家蚕抗菌肽具有明显的抑菌活性 ,利用基因工程技术生产新疆家蚕抗菌肽有助于实现工业化生产 .本研究探索通过巴斯德毕赤酵母工程菌 SMD1 1 68高密度发酵生产新疆家蚕抗菌肽 ( Cecropin-XJ)的条件 ,包括培养基中碳源、氮源、初始 p H值、磷酸盐等因素对毕赤酵母工程菌生长和抗菌肽分泌的影响 .通过多因素正交实验确定了生产新疆家蚕抗菌肽高密度发酵培养的最适培养条件 ,条件优化后毕赤酵母工程菌发酵后密度OD6 0 0 可达 48.92± 0 .5 9,较优化前提高了 3倍 ,为基因工程生产新疆家蚕抗菌肽奠定了基础     

多组分丝素蛋白-Cu(II)配合物的EPR谱解析

基于二阶微扰理论建立了对具有超精细耦合结构的多组分复杂EPR(顺磁共振)谱的解析拟合方法,并以丝素蛋白-Cu(II)配合物的EPR谱为例进行解析分析,从而有效地解释了Cu(II)离子在蚕吐丝过程中的作用.该方法和应用程序能为类似问题的解决(如Fe(II)、Mn(II)、V(III)及其它顺磁性离子配合物EPR谱的解析)提供方便.     

丝素蛋白亚基研究

丝素蛋白亚基研究于同隐蔡再生黄伟达施华芳李宏杰（复旦大学高分子系）（复旦大学生物化学系上海２００４３３）关键词丝素蛋白，氨基酸，亚基组成，柱层析，聚丙烯酰胺凝胶电泳作为天然纤维的蚕丝在国防、工农业生产、医药卫生及人们日常生活中应用日益广泛，有关...