硫酸浓度对纳米级SO4^2-／TiO2固体超强酸的影响

用锐钛型纳米TiO2制备了纳米级SO4^2-／TiO2固体超强酸，分析了硫酸浓度不同时其比表面积、失重率、红外光谱及催化活性的不同。当硫酸浓度为1．0mol／L时，它在450～900℃的失重率为3．3％，比表面积为105．2m^2／g，对乙酸和丁醇酯化反应的酯化率达到98．4％。玻璃球负载纳米级SO4^2-／TiO2固体超强酸的重复使用性能好，在乙酸和丁醇的酯化反应中重复使用9次后的酯化率才由初次的99．3％变为84．9％。     

一个改进的Mihlin- H(o^)rmander乘子定理

文章利用 k阶 Stein函数理论 ,通过减弱 m(x)所满足的条件 ,得到了一个改进的 Mihlin- H(o^)rmander乘子定理.     

搅拌型芦荟果粒酸奶稳定性的研究

实验结果表明：在能够打碎酸凝乳条件下，以慢速短时间搅拌效果较好；添加8～10％的芦荟果粒，3‰的变性淀粉，产品均匀细腻，质量稳定。     

M／M／n／n／m型排队系统的优化设计及应用研究

利用有限状态生灭过程的稳态解推导了M／M／n／n／m型排队系统的损失概率公式和系统占有率公式，对服务台数n和顾客源m的优化设计方法进行了理论探讨和可视化分析，借助于MATLAB编程获得系统的优化设计方案，并将所得理论和方法应用于有限用户损失制多信道共用通信系统的共用信道数的优化配置研究。     

N-terminal of L protein of vesicular stomatitis virus contains a new signal sequence

The L protein (241kD) of vesicular stomatitis virus (VSV) is the most important snbnnit of the replication complex. The existence of specific localization signal in the L protein was investigated by making recombinant constructs expressing truncated mutants of the L protein fused to green fluorescent protein (GFP) in transient transfection assays. The chimeric genes encoding varied N-terminal of L and GFP gene were put under the control of T7 promoter or CMV promoter. The fusion proteins were transiently expressed in BHK-21, COS-7, CHO or Hep G2 cells. When more than 120 residues were deleted or only 96 residues were kept on the N-terminal, the fusion proteins were shown to be distributed throughout the cells, cytoplasm and nucleus under the confocal microscope. However, other chimeric proteins with 120 or more amino acids were dotted and distributed in the perinuclear regions. And the fusion protein with 96—120 aa has the similar distribution. A thirteen-residue peptide QGYSFLHEVDKEA (108—120) was identified as localization signal, whose function would be absolutely distributed with the deficiency of D or V. Our results show that there is an independent localizing signal in N-terminal domain of L protein of VSV and this functional signal is conserved in different cell lines.     

Holocene lake deposits of Bosten Lake, southern Xinjiang, China

A 9.25-m-long sediment core from Bosten Lake,Xinjiang, provides detailed information about changes in the water budget and biological acticity over the last 8400 cal-endar years. The chronology is constructed from six AMS radiocarbon dates on the terrestrial plant remains. Based onanalyses of TOC, CO3, detrital compounds and biogenic SiO2,lake level fluctuations and periods of remarkably-negative water budget appeared at 8.4-8.2 cal ka, 7.38-7.25 cal ka,5.7-5.5 cal ka, 3.7-3.4 cal ka and 3.3-2.9 cal ka, respec-tively. As they are in-phase with low lake levels at Sumxl Co and Bangong Co in western Tibet Plateau and with paleo-lakes in Inner Mongolia, a climate-induced change to some-what drier and warmer conditions is inferred. A further drop in lake level after 1320 AD of about 200 yr duration may heattributed to a negative water balance prior to the main phase of the Little Ice Age. Deep and stable lake phases of 1500 yr and 1800 yr duration at 7.2-5.7 cal ka and 5.5-3.7cal ka coincide with maximum moisture during the Holocene Megathermai in China. The long term trend towards aridity since about 4.3 cal ka can dearly be recognised. The reduced water budget of Bosten Lake from 640-1200 AD may be attributed to local effects.     

Effects of hyaluronic acid－chitosan－gelatin complex on the apoptosis and cell cycle of L929 cells

With the development in the field of tissue engineering, the interaction between biomaterials and cells has been deeply studied. Viewing the cells seeded on the surface of materials as an organic whole, cell cycle and apoptosis are analyzed to deepen the study of cell compatibility on biomaterials, while cell proliferation and differentiation are studied at the same time. In this paper, hyaluronic acid is incorporated into the chitosan-gelatin system. Propidium iodide (PI) was used in cell cycle analysis and the double-staining of cells with annexin-V and PI was applied in cell apoptosis analysis. The results show that incorporated hyaluronic acid shortens the adaptation period of cells on the material surface, and then cells enter the normal cell cycle quickly. In addition, added hyaluronic acid inhibits cell apoptosis triggered by the membranes. Therefore, hyaluronic acid improves the cell compatibility of chitosan-gelatin system and benefits the design of biomimetic materials.     

济南市郊直翅目（Orthoptera）昆虫群落多样性研究

采用生态学、分类学和统计学方法，对济南市郊直翅目昆虫的群落结构、时序动态、物种丰富度与生态因子的相关性进行了研究．运用统计分析软件SPSS，把直翅目昆虫栖境划分为6种生境型，认为草地－撂荒地型和河岸－水滨—耕作地型为济南市郊典型的“直翅目昆虫发生库”。     

垄断企业的反垄断型经营模式——来自深圳供电局建设服务型企业的调查

深圳供电局成立于1979年,是广东省电力集团公司的核心企业和国有大型企业。供电人口约390万,供电面积2020平方公里。2000年供、售电量分别为179.23亿千瓦时和168.84亿千瓦时,均列全国大中城市供电企业第四位。在我国成功入世以后,我国企业,特别是垄断企业,目前已普遍感受到了今后直面国际竞争的巨大压力。而深圳供电局由于多年来预选模拟面临我国入世后的剧烈竞争局面,自觉在提高服务质量的运营机制方面与国际接轨,破除“皇帝女儿不愁嫁”的垄断型经营模式,成功地推进自身向服务型企业的转化,根据我们的调查结论,他们完全有能力经受得住日后…