SO2等离子体处理对聚氨酯抗凝血性影响的研究

用二氧化硫辉光放电等离子体表面处理含有不同官能团的聚氨酯薄膜，研究了薄膜表面官能团对不同凝血因子的影响。结果表明，凝血酶可被多种基团特别是磺酸基团抑制，部分凝血活酶的抗凝血性受到羧酸、醚键和磺酸共同作用，而凝血酶原可能受到羟基、醚键和磺酸的协同影响。     

丝素改性胶原膜的低温等离子体改性及体外抗凝血性研究

选用SO2、NH3、CO2三种工作气体，采用低温等离子体技术对丝素改性胶原膜进行了表面改性。运用X光电子能谱分析了材料的表面性质。材料的体外抗凝血性能由体外凝血时间——凝血酶原时间(PT)、部分凝血活酶时间(APTT)、凝血酶时间(TT)作为评价标准。结果表明，SO2、CO2等离子体处理可分别在材料表面引入磺酸和酸酸基团，材料的体外抗凝血性得到很大的改善。NH3等离子体处理可以增加材料表面的氨基的数目，它对材料的抗凝血性没有贡献。     

两种不同结构TiO2薄膜生物活化能力比较

采用非平衡磁控溅射法制备了2种不同结构的TiO2薄膜，对所得TiO2薄膜分别运用碱处理和酸处理2种化学方法进行表面处理，期望在材料表面获得羟基活性基团。运用X射线衍射（XRD）、X射线光电子能谱仪（XPS）等手段研究了薄膜的表面结构、成分等。利用傅立叶红外技术（FTIR）对活化处理前后样品表面的羟基基团进行检测，同时利用四探针测试仪对薄膜的电阻率进行了测量。结果表明，运用碱处理和酸处理2种方法，可以在锐钛矿型TiO2薄膜表面形成活性羟基基团；相比于金红石型TiO2薄膜，锐钛矿型具有较好的羟基活化能力。     

丝素膜表面磺酸化研究

从蚕丝中提取丝素蛋白制备成纯丝素膜及PEGO丝素膜,首次采用硫酸处理,在丝素膜材料表面引入了磺酸基团;采用电子能谱和全反射红外光谱分析材料的表面性质,表明硫酸处理丝素膜,可以使PEGO丝素膜表面带上磺酸基团,以共价键的结合方式牢固地固定在表面.这将大大提高丝素膜的抗凝血性,防止细胞在丝素膜上的粘附.X射线衍射表明,丝素膜在硫酸处理后,其结晶度增加,特别是silk Ⅰ的结晶,但是,经硫酸处理后,丝素膜的断裂伸长率与强度有所下降.     

活性炭表面含氧官能团对TiO_2/AC的吸附和光催化活性的影响

通过硝酸氧化和热处理获得了表面含氧基团和织构显著变化的活性炭,考察了所得活性炭载纳米TiO_2光催化剂(TiO_2/AC)对亚甲蓝和甲基橙的吸附和光催化降解,研究了活性炭表面含氧基团对TiO_2/AC吸附和光催化活性的影响。结果表明,活性炭表面含氧基团的变化比织构显著,其表面含氧基团尤其是羧酸基团对TiO_2/AC的吸附和光催化活性有决定性的影响;同时,针对降解物的电荷性质不同,活性炭表面含氧基团的影响有差异,对阳离子亚甲蓝的吸附和光催化活性的影响比阴离子甲基橙的显著,250℃下脱除表面羧酸后的催化剂对亚甲蓝的光催化活性明显降低而对甲基橙的则稍有增加。     

不同梳状键接结构聚羧酸在高性能混凝土中的应用性能和作用机理

梳状结构聚羧酸具有优异的分子结构可设计性,为绿色混凝土的生态化、高性能化提供了理论基础和技术支撑。本研究以聚丙烯酸(PAA)、羟基甲氧基聚氧乙烯丙烯醚(HMPEPG)、氨基甲氧基聚氧乙烯丙烯醚(AMPEPG)为反应原料,根据酯化和酰胺化反应,分别设计合成了以酯基和酰胺键接主侧链的梳状结构聚羧酸(PCE),并通过红外光谱(IR)和分子量测试证明了分子结构符合预期设计。水泥净浆和混凝土应用性能结果表明,酯基键接聚羧酸的初始净浆流动度和混凝土早期强度更优,酰胺键接聚羧酸的净浆流动度保持能力和混凝土扩展度更优。二者的作用机理存在显著差异,酯基键接聚羧酸的吸附行为更稳定,更易快速成核水化,酰胺键接聚羧酸的表面张力更低,气-液界面取向能力更强。本研究合成的酯键和酰胺键两种方式连接主侧链的梳状结构聚羧酸可分别应用于高早强要求和高泵送要求的混凝土,具有较好的应用前景和推广价值。     

异喹啉及其衍生物在银电极上吸附行为的研究

借助于表面增强拉曼散射技术，研究了异喹啉及其衍生物在盐酸溶液中Ａｇ电极上的吸附行为。结果表明：异喹啉是通过Ｎ原子的作用垂直地吸附在Ａｇ电极表面上；５－羟基异喹、１，５－二羟基异喹啉和甲基－３异喹啉羧酸脂是通过环上的π电子与金属作用，平躺地吸附在金属表面上，其中５－羟基异喹啉的π反键轨道能接受金属表面电子密度的反馈，形成“反馈π键”，吸附作用较强；１－羟基异喹啉和１－羟基异喹啉分别通过Ｏ原子和ＣＯＯ     

黏合剂活性基团对HTPB推进剂力学性能的影响机制

为了研究端羟基聚丁二烯(HTPB)固体推进剂中黏合剂体系在储存过程中容易发生化学反应的基团的活性特点,寻找合适途径抑制推进剂老化,从而延长火箭发动机的储存寿命,本文中通过量子化学理论计算以及红外光谱和力学性能测试等实验方法,研究了甲苯二异氰酸酯(TDI)/HTPB黏合剂中的活性基团在自然储存条件下可能发生的化学变化及其对HTPB推进剂力学性能的影响。研究结果表明,HTPB推进剂中黏合剂分子易发生反应的部位应为C=C键或氨基甲酸酯基团,在推进剂的加速老化和自然储存过程中,C=C键氧化分解引起的黏合剂网络结构破坏,是导致推进剂力学性能下降的主要原因。     

氧化钛薄膜表面羟基活化能力及对生物相容性的影响

采用非平衡磁控溅射法制备了3种不同结构的TiO2薄膜,对所得TiO2薄膜运用碱处理方法进行表面处理,期望在材料表面获得羟基活性基团.运用X射线衍射(XRD)研究了薄膜的表面结构.利用傅里叶红外技术(FTIR)和X射线光电子能谱仪(XPS)等手段对活化处理前后样品表面的羟基基团进行检测,并对活化前后样品进行了内皮细胞培养和血小板黏附实验.结果表明,运用碱处理方法,可以在锐钛矿型以及金红石与锐钛矿的混晶结构TiO2薄膜表面形成活性羟基基团;相比于金红石型TiO2薄膜,混晶结构和锐钛矿型具有较好的羟基活化能力.生物相容性实验表明,碱活化处理后样品表面细胞生长数目多于活化前样品,血小板黏附数量少于活化前样品,表面活性基团的存在有利于提高TiO2薄膜材料的生物相容性.此外,影响TiO2薄膜表面生物活化性能的因素进行了初步探讨.     

聚乙烯辐照接枝体系中添加金属盐对接技率的影响

采用辐照接枝的方法，在高密度聚乙烯(HDPE)上接枝丙烯酸(AA)和对苯乙烯磺酸钠(SSS)，从而削备出了一种含羧酸基团和磺酸基团的阳离子交换膜。详细研究了接枝体系中引入添加剂醋酸钠或氯化钠对接枝率的变化规律．实验表明，在预辐照接枝和共辐照接枝中，当AA接技PE或AA与SSS共同接枝PE时，强碱弱酸盐醋酸钠通过pH效应同离子效应对接枝率呈现复杂的影响，而中性盐氯化钠经离子对效应显著提高接枝率。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.