MEMS--电子领域的新宠

微机电系统技术(MEMS)是随着半导体集成电路微细加工技术和超精密机械加工技术的发展而发展起来的．其微型化、集成化、批量生产和多学科交叉等优良特性将对人类社会生活带来巨大的进步，是电子领域的新宠。     

经砷诱导人肝细胞L02获得砷耐受性的研究

砷是自然界普遍存在的毒性较强的类金属元素。几乎所有生物在进化中都产生了对砷毒性的耐受性。生物体对砷的耐受机制受到广泛关注。本实验采用低剂量(4μmol／L)NaAsO2诱导人体正常肝细胞株LO2,利用噻唑兰检测法(MTT)计算细胞生存率及半数致死量反映细胞对砷耐受性的改变，结果发现低剂量砷诱导6周后，在48h急性砷中毒试验中，实验组LC50为23．0μmol／L，对照组为11．9μmo1／L，实验组明显高于对照组，说明细胞对急性砷中毒耐受性明显提高。     

磷酸钙氨基磺酸复合体系催化乙氧基化反应

磷酸钙-氨基磺酸，用于催化乙氧基化反应。通过正交试验，确定了较佳的催化工艺条件，通过色质连用仪测定了乙氧基化产物的分子量分布。研究结果表明，氨基磺酸的加入对乙氧基化反应的反应速度影响较大，当磷酸钙的加入量为正辛醇质量的1％，氨基磺酸的加入量为正辛醇质量的0．75％时，乙氧基化反应速率最快。当摩尔数n(正辛醇）：n(环氧乙烷(EO))=1：4，催化剂用量为1％，在120℃下反应90min,正辛醇的转化率可达到89．3％，同时乙氧基化产物的分子量分布选择性指标是相同条件下NaOH为催化剂的1．8倍，具有较好的窄分布效果。     

银行信息化建设的过程、问题和对策

回顾了银行信息化建设的各个历史阶段,描述了在基层银行开展信息化建设的过程、取得的成就和存在的问题,提出了下一步银行信息化建设工作中应采取的对策.     

含烯丙基环氧树脂/硫体系的固化特性研究

文中首次报导了含烯丙基双酚A型环氧树脂(DADGEBA)在硫磺作用下的固化行为。通过凝胶化时间,DSC,FTIR的测定,对该体系的固化特性进行了研究,提出了硫磺与环氧树脂DADGEBA的反应机理。该体系可在高温下固化,有两个明显的放热峰;固化反应的机理可能为硫磺在高温下八元环首先发生均裂从而产生链自由基,然后硫磺自由基一方面与烯丙基双键作用进行自由基加成反应;另一方面烯丙基中α位的活泼氢向硫磺链自由基发生转移,从而产生巯基,然后巯基与环氧基团发生开环反应。最终,通过上述两种反应使整个体系交联固化。     

中南民族大学学报(自然科学版)刊文被美国化学文摘收录的统计分析

对收录于美国化学文摘的中南民族大学学报(自然科学版)2000～2002年间的刊文进行了统计分析,重点对收录刊文的时频及分类进行了较详细统计及分析. 结果表明:平均收录时频为9月.刊文的年平均收录率为71.7%,分析了未被收录刊文的可能原因.     

Analysis of simple sequence repeats markers derived from Phytophthora sojae expressed sequence tags

Five thousand and eight hundred publicly available expressed sequence tags (ESTs) of Phytophthora sojae were electronically searched and 415 simple sequence repeats (SSRs) were identified in 369 ESTs. The average density of SSRs was one SSR per 8.9 kb of EST sequence screened. The most frequent repeats were trinucleotide repeats (50.1%) and the least frequent were tetranucleotide repeats (8.2%). Forty primer pairs were designed and tested on 5 strains of P. sojae. Thirty-three primer pairs had successful PCR amplifications. Of the 33 functional primer pairs, 28 primer pairs produced characteristic SSR bands of the expected size, and 15 primer pairs (45.5%) detected polymorphism among 5 tested strains of P. sojae. Based on the polymorphisms detected with 20 EST-SSR markers, the 5 tested strains of P. sojae were clustered into 3 groups. In this study, the SSR markers of P. sojae were developed for the first time. These markers could be useful for identification, genetic variation study, and molecular mapping of P. sojae and its relative species.     

Deep-water Earliest Oligocene Glacial Maximum （EOGM） in South Atlantic

The most prominent cooling event of the Earth surface during Cenozoic in the long-term transition from a non-glaciated planet, or “green-house world”, to a polar, glaciated planet, or “ice-house world”, is the Earliest Oligocene Glacial Maximum (EOGM) above the Eocene/Oligocene boundary at about 33.7 Ma. Planktonic and benthic foraminiferal oxygen and carbon isotopes, carbonate content, and coarse fraction, along with high-resolution color reflectance and magnetic susceptibility records during 35-30 Ma, from deep-water Sites 1262 and 1265, Ocean Drilling Program (ODP) Leg 208 in South Atlantic, reveal the global cooling event occurring in both surface and deep oceans. The results show that the earliest Oligocene δ^18O values during 33.5-33.1 Ma represent the magnitude of continental ice sheets on east Antarctica and indicate the large decrease in both surface and deep water temperatures of worldwideoceans. The δ^13C records show the large excursion during the period of EOGM event and indicate some types of shift in global carbon reservoir, probably demonstrating the sudden increase in organic carbon burial rates and the changes in the distribution and timing of production. At the same time, lithologic composition, carbonate content, color reflectance, and coarse fraction brought about significant changes close to the Eocene/Oligocene boundary, reflecting the abrupt deepening in the carbonate compensation depth (CCD). Changes in carbonate content were revealed from the color reflectance identify periodicities associated with eccentricity of the Earth‘s orbit (100 and 400 ka), further indicating orbitally forced global climate variations in the Early Oligocene.     

浅淡科学数据共享工程建设的战略取向

科学数据共享工程自2002年启动以来,先后对多个部门和行业进行了试点建设,取得了良好的开端。本文在调查、分析的基础上,针对科学数据共享工程的国家目标,从12个方面分析和探讨了科学数据共享工程的战略取向,以期为“十一五”的科学数据共享工程建设与发展提供参考。