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91.
92.
本文通过对带钢窄边线状裂纹缺陷的金相显微组织观察和扫描电镜与能谱分析,确定了带钢窄边线状裂纹缺陷的形成原因,并针对原因提出了相应的预防措施,有效地控制了带钢窄边线状裂纹缺陷的重复发生。 相似文献
93.
同志们,今天我们在这里隆重召开2005年度科技工作总结表彰大会,会议开得非常好。梁铁总工程师作的2005年度科技工作报告,总结了去年的科技工作,布置了今年的科技工作,这是对广大科技工作人员过去工作的肯定和今后工作的展望。我们还表彰了一批科技工作先进个人、先进集体和先进单位,并聘任了第三批技术专家和第四批学科带头人,这说明柳钢的科技工作是欣欣向荣的。 相似文献
94.
BiologicalEffectsofFlammulinaVelutipesRichinREonChineseKunmingMiceLiangDingbang(梁定邦);CuiDefang(崔德芳);ZhangJintong(张金桐)(Departm... 相似文献
95.
聚酯-聚醚嵌段共聚物的合成及抗静电性能研究 总被引:1,自引:0,他引:1
研究和分析了PEG分子量、加料次序、反应时间和温度、物料比例、分散剂和固相缩聚等因素对PET-PEG嵌段共聚物分子量和耐水性的影响。合成的嵌段共聚酯醚与PET共混纺丝可以显著改善PET纤维的抗静电性能。 相似文献
96.
The use of a dome osteotomy in the treatment of infantile tibia vara is reportedly associated with insufficient intraoperative assessment of the correction achieved. This article discusses a method to overcome this problem and the long-term advantages of using a dome osteotomy in the treatment of this disease. 相似文献
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98.
Increasing the parallelism in transaction processing and maintaining data consistency appear to be two conflicting goals in designing distributed database systems (DDBSs). This problem is especially difficult if the DDBS is serving long-lived transactions (LLTs). A special case of LLTs, called sagas, has been introduced that addresses this problem. A DDBS with sagas provides high parallelism to transactions by allowing sagas to release their locks as early as possible. However, it is also subject to an overhead, due to the efforts needed to restore data consistency in the case of failure. We conduct a series of simulation studies to compare the performance of LLT systems with and without saga implementation in a faulty environment. The studies show that saga systems outperform their nonsaga counterparts under most of conditions, including heavy failure cases. We thus propose an analytical queuing model to investigate the performance behavior of saga systems. The development of this analytical model assists us to quantitatively study the performance penalty of a saga implementation due to the failure recovery overhead. Furthermore, the analytical solution can be used by system administrators to fine-tune the performance of a saga system. This analytical model captures the primary aspects of a saga system, namely data locking, resource contention and failure recovery. Due to the complicated nature of the analytical modeling, we solve the model approximately for various performance metrics using decomposition methods, and validate the accuracy of the analytical results via simulations 相似文献
99.
Epinephrine increased outflow facility and cyclic AMP in the in vitro perfused human anterior segment with a maximal facility increase of 44% occurring at approximately 2 x 10(-5) M. Cyclic AMP measured in the perfusate from anterior segments increased by 12-14 fold after administration of 10(-5) M epinephrine. Both the facility increase and cyclic AMP rise were blocked by the beta-2 selective antagonist, ICI118,551. While there was a correlation between the facility increase and elevation in cyclic AMP levels, the rise in cyclic AMP preceded the facility increase by about 1 hour, suggesting that the ultimate effect of epinephrine involved a rather slow event such as synthesis and release of prostaglandins or protein synthesis. Subsequent perfusion studies showed that very large concentrations of indomethacin were necessary to block the outflow facility effect of epinephrine, suggesting that prostaglandin synthesis did not underlie the facility effect in this system. However, 5 x 10(-5) M cyclohexamide blocked the effect on outflow facility of both epinephrine and forskolin, but did not block the rise in cyclic AMP. These studies suggest that protein synthesis may play a role in the epinephrine-induced facility increase at some point beyond the second messenger level. 相似文献
100.