利用偶联技术制备核电池用镍膜的工艺初探

曲面换能单元的核电池中镍-63的加载难以用常规源片加载法实现。采用偶联技术,对功能高分子膜的表面用偶联剂改性后进行活化处理,初步制备了镀有非放镍的高分子薄膜,并分析了此工艺的反应机理。采用该工艺可避免常规化学镀镍方法中试剂对半导体材料的损伤。     

Mechanical properties and thermal stability of nitrogen incorporated diamond-like carbon films

The nitrogen incorporated diamond-like carbon films were deposited on Si (100) substrates by arc ion plating (AIP) under different N₂ content in the gas mixture of Ar and N₂. The influence of N₂ content on the film microstructure and mechanical properties was studied by atomic force microscopy, transmission electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and nanoindentation. It was found that the hardness (H), elastic modulus (E), elastic recovery (R) and plastic resistance parameter (H/E) decrease with increasing the nitrogen content. The decrease of mechanical properties of DLC films resulted from nitrogen incorporation was associated with total sp³ carbon bond content and N-sp³C bond content. The structural modification as well as mechanical properties of the annealed nitrogen incorporated diamond-like carbon films was investigated as a function of annealing temperature. Raman spectra indicate that the I_D/I_G ratio starts to increase and G peak position shifts upward at the annealing temperature over 500 °C. The hardness and elastic modulus of thermally annealed nitrogen incorporated DLC films decreased slightly at lower annealing temperature and then significantly decreased at higher annealing temperature. The strong covalent bonding between C and N atoms is expected to be effective on their thermal stability enhancement.     

欧盟对企业合并的最新程序法规制--兼议对我国《反垄断法》立法的启示

《欧盟部长理事会关于控制企业合并的139／2004条例》于2004年5月1日生效,这是欧盟对企业合并的最新立法。相对于原有的《欧盟部长理事会关于控制企业之问合并行为的4064／89号法规》,新规定有着种种创新之处。研习其对企业合并的最新规定尤其是程序法规定,对我国当前正在进行的《反垄断法》的立法无疑有着重要的借鉴意义。     

半叶马尾藻多糖对辐射损伤小鼠脾细胞的影响

探讨了半叶马尾藻多糖[Sargassum hemiphyIlum(Turner)C．Ag．polysaccharides,SHP]对辐射损伤小鼠脾细胞的影响。用3^H-TdR(氚标记胸腺嘧啶核苷)和3^H-UR(氚标记酪氨酸)掺入法分别检测脾细胞DNA、UDS(非程序性DNA合成)和蛋白质合成,通过流式细胞术测定脾细胞周期和脾淋巴细胞CD4分子表达。20mg／kg和40mg／kg的SHP对辐射损伤小鼠DNA和蛋白质合成具有显著的刺激作用,10—40mg／kg的SHP对辐射损伤小鼠脾淋巴细胞UDS和CD4分子的表达也有明显的促进作用。脾细胞周期研究表明20mg／kg和40mg/k的SHP对辐射损伤小鼠脾细胞G0／G1期和G2／M期的细胞百分率分别有减少和增加的作用,而10—40mg／kg的SHP能够提高辐射损伤小鼠脾细胞S期的细胞百分率。SHP对辐射损伤小鼠脾细胞具有保护作用。     

Incorporation of Halogenated Amino Acids into Antibody Fragments at Multiple Specific Sites Enhances Antigen Binding

Expansion of the amino-acid repertoire with synthetic derivatives introduces novel structures and functionalities into proteins. In this study, we improved the antigen binding of antibodies by incorporating halogenated tyrosines at multiple selective sites. Tyrosines in the Fab fragment of an anti-EGF-receptor antibody 059–152 were systematically replaced with 3-bromo- and 3-chlorotyrosines, and simultaneous replacements at four specific sites were found to cause a tenfold increase in the affinity toward the antigen. Structure modeling suggested that this effect was due to enhanced shape complementarity between the antigen and antibody molecules. On the other hand, we showed that chlorination in the constant domain, far from the binding interface, of Rituximab Fab also increased the affinity significantly (up to 17-fold). Our results showed that antigen binding is tunable with the halogenation in and out of the binding motifs.     

Strong Band Gap Blueshift in Copper (I) Oxide Semiconductor via Bioinspired Route

Semiconductors have numerous applications in both science and technology. Several methods have been developed to engineer their band gap, which is one of the most important parameters of semiconductors. Here, it is shown that the incorporation of various amino acids into the crystal lattice of copper (I) oxide, akin to the way living organisms incorporate organic macromolecules into minerals during biomineralization, leads to significant shrinkage in the volume of the host unit cell and a strong blueshift in the band gap of up to ≈18%. In examining the potential location of the bio‐organic molecules within the inorganic host's lattice, a very good fit between the proposed model of incorporation and experimental findings is found. The bioinspired phenomenon of band gap widening is thought to be attributable to the void‐induced quantum confinement effect, even though observed in micrometer‐sized crystals. This hypothesis is supported by developing a tight‐binding model that is found to fit well with the experimental data. The outcome of this research could profoundly impact the fields of light‐emitting and spin‐based devices as well as opens up a new bioinspired route to tune the band gap of semiconductors.     

Bread fortified with dietary fibre extracted from culinary banana bract: its quality attributes and in vitro starch digestibility

The effect of fortification of dietary fibre (DF) on dough rheology, quality characteristics and in vitro starch digestibility of bread was studied. Bread was prepared incorporating DF (2–4 g per 100 g of flour mixture). Rheological study of dough showed an increase in dough stiffness and elasticity with higher incorporation of the DF. The results of chemical composition revealed that addition of DF increased total DF (19.65 g per 100 g) content of bread. However, incorporation of 2 g per 100 g DF of flour mixture with 66 g per 100 g moisture showed higher water retention and specific volume of 86.76% and 5.83 cm³ g⁻¹, respectively, which was close to control bread. Improved textural property with acceptable sensory attributes was observed for bread fortified with 2 g per 100 g DF of flour mixture and 66 g per 100 g moisture content. Incorporation of DF (2–4 g per 100 g of flour mixture) showed a decrease in rapidly digestible starch (RDS) and an increase in slowly digestible starch (SDS) content with lower predicted glycaemic index (pGI) than control bread.     

维生素A对CD4^＋和CD8^＋细胞辐射效应的影响

应用ＣＤ４和ＣＤ８单克隆抗体，采用铺皿法分离并获得ＣＤ４＾＋和ＣＤ８＾＋细胞亚群，间接免疫荧光试验鉴定细胞纯度分别为８９．２％和８５．８％，以＾３Ｈ－ＴｄＲ参入法比较ＣＤ４＾＋，ＣＤ８＾＋细胞辐射敏感性及加入ＶｉｔＡ后对两种细胞亚群ＤＮＡ合成的影响，发现ＣＤ４＾＋和ＣＤ８＾＋细胞经过不同剂量＾６０Ｃｏγ照射后其＾３Ｈ－ＴｄＲ参入均明显下降。加入５μｇ／ｍｌＶｉｔＡ后，受照射的ＣＤ４＾＋细胞参与无明     

串电阻限流并车法

在矿山自电发电并车并网系统中，通过在原有准同步并车并网系统的基础上，增加适当，安全的可变电阻，改准同步并车并网为近同步或同步并车并网，从而加快了并车并钢网速度，提高了供电安全，并使矿山获得较好的技术经济效益。