高硒及高硒高维生素E合用对十二月龄大鼠血清MDA和ALT的影响

给动物喂食高Se、高vitaminE、高Se高vitaminE合用饲料 ,探讨单独及合用高Se、高vitaminE对十二月龄动物血清中MDA和ALT的影响。结果显示 ,与对照组比较 ,单独及合用高Se、高vitaminE均可显著降低血清中MDA的含量 (P <0 0 1 ) ,高vitaminE尚能使血清中ALT水平升高 (P <0 0 5 ) ,而高Se高vitaminE合用则可纠正高vitaminE引起的血清中ALT水平的升高     

辉光放电质谱法在高纯材料分析中的应用

高纯材料是现代高新技术发展的基础,在电子、光学和光电子等尖端科学领域发挥着重要作用。采用固体样品直接分析的辉光放电质谱法(GDMS),在高纯金属、高纯半导体材料的痕量和超痕量杂质分析中有着非常广泛的应用。综述了GDMS法对高纯金属、高纯半导体材料进行的元素分析,并对分析过程中工作参数、溅射时间、干扰峰等因素的影响进行了阐述。同时,也详述了应用GDMS法对高纯金属钛、镉,高纯半导体硅,分别进行的痕量杂质元素分析,结果显示放电稳定性良好,典型元素含量的相对标准偏差均在较为理想范围内。GDMS应用前景广泛,未来,GDMS将在除固体样品之外的其他样品类型的分析领域中发挥重要作用。     

高硒情况下维生素E对幼龄大鼠抗氧化作用的研究

研究了高Se或高维生系E下,幼龄大鼠体内抗氧化活性的变化以及高Se下,维生素E对其体内抗氧化水平的影响。将三月龄Wistar大鼠32只随机分成4组：正常饲料组、高Se高维生素E饲料组、高Se饲料组和高维生素E饲料组。饲至十周末,处死大鼠,按试剂盒要求分别取其血液、心、肝、肾制成标本测SOD、CAT活性及MDA、GSH含量。结果表明,高Se或高维生素E下饲养下的大鼠与对照组比较,血液中SOD活性明显下降;维生素E能明显抑制高Se大鼠血液中SOD活性的下降。结论：单独高Se或高维生素E会降低幼龄大鼠的抗氧化活性,而维生素E能明显提高高Se下幼龄大鼠体内抗氧化活性。     

高硒情况下维生素E对老龄大鼠血清中抗氧化作用的影响

研究了高Se或高维生素E下，老龄大鼠体内抗氧化活性的变化以及高Se下维生素E对其体内抗氧化水平的影响。将十二月龄Wistar大鼠32只随机分成4组：（1）正常饲料组；（2）高Se饲料组；（3）高维生素E饲料组；（4）高Se高维生素E饲料组。饲至十周末，处死大鼠，按试剂盒要求取其血液制成血清测GSH－Px,SOD活性，MDA含量。结果表明，高Se或高维生素E下饲养下的大鼠与对照组比较，血清中GSH－Px活性升高（P＜0．05）。SOD活性未见改变，MDA含量分别减少50％和56％，有显著差异（P＜0．01）；维生素E与高Se合用与高Se组比较能进一步同GSH－Px,SOD活性（P＜0．01）。结论：高Se会升高老龄大鼠的抗氧化活性，而与维生素E合用更加升高老龄大鼠血液中抗氧化活性。     

Crystallization and reinforcement of poly (vinylidene fluoride) nanocomposites: Role of high molecular weight resin and carbon nanotubes

The effect of high molecular weight resin and multi-walled carbon nanotubes (MWCNTs) on the crystallization, rheological and dynamic mechanical properties of poly (vinylidene fluoride) (PVDF) composites was investigated. A synergetic effect of the high molecular weight resin and MWCNTs on the nucleation in the crystallization process of the matrix has been observed, and their contributions to the crystallization of the matrix are two-sided. The composites containing both the high molecular weight resin and MWCNTs have much higher crystallization peak temperatures but lower crystallinity, especially for samples with high MWCNT content. For the isothermal crystallization at relative high temperatures, higher Avrami exponent and shorter half-time of crystallization are observed for the composites containing both the high molecular weight resin and MWCNTs. The introduction of the high molecular weight resin not only reinforces the matrix, but also promotes the dispersion of MWCNTs. The reinforcement and synergetic nucleation effects of the high molecular weight resin and MWCNTs were also confirmed by dynamic mechanical analysis.     

高压化学

高压化学在现代科学中占有重要的地位,并在过去二十几年中取得了快速的发展。本文简要介绍了高压化学及高压化学研究领域在诸多方面的研究进展,其中包括高压无机化学和高压有机化学,以及高压在化学合成和化学过程研究中的应用,展示了高压化学的研究现状及其在许多方面的应用前景。     

高挥发分烟煤的热解、燃烧特性研究

采用固定床热解反应器、热解 红外联用仪 (Py FTIR)和热重分析仪 ,考察了高挥发分烟煤的热解、燃烧特性 ,实验结果表明 ,高挥发分烟煤在热解过程中放出大量烃类气体 ,从燃烧试验看 ,明显分为热解段和燃烧段 ,且热解段挥发分的释放非常迅速 ,从而揭示出高挥发分烟煤燃烧过程中产生大量黑烟的原因。     

Lipid lowering effects of high linoleate and high alpha-linolenate diets in rats and mice. Consequence of long-term feedings.

Diets high in linoleate (safflower oil) or high in alpha-linolenate (perilla oil) were fed to rats for 11 months, and the effects of the diets on plasma and tissue lipids were compared. The plasma levels of total cholesterol (Cho), phospholipids (PL) and triacylglycerol (TG) were significantly lower in the high alpha-linolenate group than in the high linoleate group, the differences being more than 30% in the levels of total Cho and TG. The diets had differential effects on the lipid contents of major tissues: the TG level in muscle was higher but both the TG level in depot fat and the PL level in muscle were lower in the high alpha-linolenate group than in the high linoleate group. In order to clarify whether or not the hypolipidemic effect of the high alpha-linolenate diet was due to changes in the distribution of lipids among tissues, whole body lipids were estimated in mice fed these diets for 5 months. The whole body Cho content was significantly lower, by 28%, in the high alpha-linolenate group compared with the high linoleate group, but the total lipid content, PL and neutral lipids were similar between the groups. Our results indicate that the high alpha-linolenate diet has a more potent cholesterol lowering effect in plasma and body tissue than the high linoleate diet; interestingly, whole body TG levels are similar but tissue distributions of TG are different between the two dietary groups.     

High refractive index adamantane‐based silicone resins for the encapsulation of light‐emitting diodes

The encapsulation of high power light emitting diode (LED) needs the silicone resins to have relative high refractive index and thermal‐aging properties. Herein, high refractive index adamantane‐based phenyl epoxy‐silicone (APES) resins for LED encapsulation were synthesized by the sol‐gel condensation of 1‐adamantane methanol propyltrimethoxysilane‐3‐urethane, γ‐(2,3‐epoxypropoxy)propytrimethoxysilane and diphenylsilanediol. These adamantane‐based silicone resins have multifunctional groups including adamantyl group, phenyl group, and epoxy group in order to meet the various requirements for LED encapsulation. Importantly, the adamantane group in the silicone resins benefits for high refractive index and anti‐thermal properties. These APES resins were characterized by proton nuclear magnetic resonance and Fourier transform infrared spectroscopy. When APES resins were cured by methylhexahydrophthalic anhydride, they showed relatively high refractive index of 1.56, high hardness, and high thermal resistance. The encapsulated LED demonstrated high adhesion properties by red‐ink tests. These merits make adamantane‐based silicone resins promising candidates as LED encapsulation materials.     

Electrochemical Synthesis of Tetrahexahedral Rhodium Nanocrystals with Extraordinarily High Surface Energy and High Electrocatalytic Activity

Noble metal nanocrystals (NCs) enclosed with high‐index facets hold a high catalytic activity thanks to the high density of low‐coordinated step atoms that they exposed on their surface. Shape‐control synthesis of the metal NCs with high‐index facets presents a big challenge owing to the high surface energy of the NCs, and the shape control for metal Rh is even more difficult because of its extraordinarily high surface energy in comparison with Pt, Pd, and Au. The successful synthesis is presented of tetrahexahedral Rh NCs (THH Rh NCs) enclosed by {830} high‐index facets through the dynamic oxygen adsorption/desorption mediated by square‐wave potential. The results demonstrate that the THH Rh NCs exhibit greatly enhanced catalytic activity over commercial Rh black catalyst for the electrooxidation of ethanol and CO.     

高交联大孔苯乙烯/二乙烯苯共聚物的合成及其孔结构的研究Ⅱ

本文对高交联大孔苯乙烯/二乙烯苯共聚物在干态、湿态与溶胀态的孔结构进行了研究。结果表明,在不同的状态中,高交联共聚物的孔结构是不相同的,它们的孔结构会发生变化。但是,它们的孔结构变化远小于低交联共聚物,也就是说,高交联大孔共聚物的孔结构比低交联共聚物的孔结构稳定。 鉴于高交联大孔共聚物的孔结构较稳定,作者把它用作高效液相色谱的进行了初步实验。结果表明,高交联共聚物可做为高效液相色谱的载体固定相。     

合成高密度烃类燃料研究进展

本文对合成高密度烃类燃料的进展进行了总结,分别对多环烃类燃料、高张力笼状烃类燃料和添加纳米级微粒的燃料进行了评述.以烃类物质为原料,通过聚合、加氢、异构等工艺合成的多环高密度燃料拥有较高的能量密度和较佳的稳定性能,是目前高密度燃 料的发展重点.高张力笼状烃类燃料和添加纳米级微粒的燃料拥有更大的密度(一般大于1g/ cm3)和燃烧热值,是极具发展前景的新一代燃料。     

聚合物在高压下的结构、形态和性能（下）

聚合物在高压下的结构、形态和性能（下）张雄伟，黄锐（成都科技大学塑料工程系，成都，６１００６５）在上篇中我们介绍了结晶性聚合物在高压下结晶的结构和形态。本篇将介绍聚合物在高压下的结晶动力学和热力学以及聚合物在高压下的退火等方面内容。２高压结晶动力学研...     

离子的胶体状态与其电化学储能极限

阳离子氧化还原化学是电化学储能技术中最核心的储能机理,如何高效快速利用氧化还原活性阳离子是发展兼具高功率密度与高能量密度储电技术的关键。 处于胶体状态的阳离子可形成热力学平衡态和非平衡态,具有高反应活性和低离子迁移势垒,展现出独特的电化学特性。 本文着重介绍氧化还原活性阳离子的胶体状态与其在电化学储能上的应用,并从热力学和动力学方面阐述其储能机理,以及活性胶体离子电极和超级电容电池的构筑。 利用胶体的高比表面积、高离子吸附能力和荷电离子梯度分布等特性,创造性地构筑胶体超级电容电池,解决了现有电化学储能电极材料体系中高容量与高功率不能兼具的问题,同时开拓了胶体体系新的应用方向。     

光盘存储材料及其新进展

本文简要叙述光盘写入、读出和擦除的机理并对近年来有机记录介质的研究重点及其相应的技术动向做了分析.当前的研究与开发的重点是具有高记录密度,数据传输速率快、稳定性好、载噪比大和误码率低的可擦型光盘存储材料.     

Parallel changes in non-photochemical quenching properties, photosynthesis and D1 levels at sudden, prolonged irradiance exposures in Ulva fasciata Delile

The photosynthetic response to a sudden and prolonged high irradiance exposure and following recovery at low irradiance were studied with the aim of investigating the ability to withstand and adapt to high irradiance without prior high light adaptation. When thalli of Ulva fasciata, accustomed to a low irradiance (80 micromol photons m(-2) s(-1)), were exposed to a high irradiance (1500 micromol photons m(-2) s(-1)), the D1 protein was rapidly degraded, reaching a steady-state level after 110 min. This was followed by a fast recovery when thalli were transferred to dim light. The overall ability of non-photochemical quenching of chlorophyll fluorescence decreased and levelled off at a sudden and prolonged exposure to high irradiance and followed the same trend as the D1 level with a fast recovery in dim light. Ulva had intrinsic means to acclimate rapidly to high irradiance, when non-photochemical quenching did not operate properly, by maintaining a smaller fraction of high light tolerant PSII assemblages and by maintaining a high non-photochemical quenching capacity of chlorophyll fluorescence in relation to the variable fluorescence. The overall absorption of light (400-700 nm) remained high during the period of high irradiance exposure. When Ulva were deprived of nutrients in the form of PES media the ability of non-photochemical quenching decreased at photoinhibitory conditions. The possible causes for the responses at prolonged irradiance and the mechanisms for the decrease of non-photochemical quenching are discussed, with implications for field measurements.     

High scratch and etch resistance by optimized cross-linking chemistry and density

Target of development in the field of modern automotive clear coats is the combination of high etch and high scratch resistance. For high etch resistance the cross-linking chemistry is the key factor. The property scratch resistance is mainly influenced by the cross-linking density and the flexibility of chains between netpoints. By combining these parameters high etch and scratch resistant clear coats can be formulated. As a representative example an optimized clear coat based on epoxy/acid cross-linking chemistry is discussed. The ways to achieve high cross-linking density are shown.     

不同掺杂元素对无钴高镍正极材料的影响

随着动力电动汽车的需求不断增加,发展低成本、高能量密度的锂离子电池正极材料成为关键。无钴高镍正极材料因其能量密度高、倍率性能好而受到了极大的关注。对于无钴高镍正极材料在循环过程中热稳定性差、容量衰减等问题,研究者们虽通过不同的掺杂元素改善了材料的电化学性能,但对不同掺杂元素的作用机理研究尚浅。本文综述了近年来无钴高镍正极材料掺杂改性方面的研究进展,重点总结了不同掺杂元素对改善材料电化学性能的作用机理。综合分析表明,向无钴高镍正极材料引入掺杂元素,尽管掺杂元素在材料中的主要作用机理不尽相同,但均都提高材料电化学性能,从而改善了无钴高镍材料固有的问题。最后,对无钴高镍正极材料改善策略的发展方向进行了展望,提出了多重改善策略协同应用的可行性方案。     

表面活性剂稳定高内相乳液的研究进展

具有较高孔隙率和较高比表面积的多孔聚合物材料在能源、化工、生物和功能性材料等领域应用广泛。目前越来越多的研究是以高内相乳液为模板来制备多孔聚合物材料,其中高内相乳液的稳定对多孔聚合物材料的制备十分重要。本文主要介绍了近年来发展的多种用于高内相乳液滴稳定的表面活性剂,以及以高内相乳液为模板制备得到的多孔聚合物材料在多个领域中的应用。     

Biredox Eutectic Electrolytes Derived from Organic Redox‐Active Molecules: High‐Energy Storage Systems

One promising candidate for high‐energy storage systems is the nonaqueous redox flow battery (NARFB). However, their application is limited by low solubility of redox‐active materials and poor performance at high current density. Reported here is a new strategy, a biredox eutectic, as the sole electrolyte for NARFB to achieve a significantly higher concentration of redox‐active materials and enhance the cell performance. Without other auxiliary solvents, the biredox eutectic electrolyte is formed directly by the molecular interactions between two different redox‐active molecules. Such a unique electrolyte possesses high concentration with low viscosity (3.5 m , for N‐butylphthalimide and 1,1‐dimethylferrocene system) and a relatively high working voltage of 1.8 V, enabling high capacity and energy density of NARFB. The resulting high‐performance NARFB demonstrates that the biredox eutectic based strategy is potentially promising for low‐cost and high‐energy storage systems.