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81.
The existence of water phase occupies oil flow area and impacts the confined oil flow behavior at the solid substrate in inorganic nanopores of shale oil reserv...  相似文献   
82.
由于传统的 AR 模型定阶方法在小样本情况下经常会失效,所以提出一种基于可逆跳马尔科夫蒙特卡罗(MCMC)的 AR 模型定阶方法,仿真结果表明该方法可行有效.  相似文献   
83.
嵌入式SRAM的优化修复方法及应用   总被引:2,自引:1,他引:1  
为了提高SRAM的成品率并降低其功耗,提出一种优化的SRAM.通过增加的冗余逻辑及电熔丝盒来代替SRAM中的错误单元,以提高其成品率;通过引入电源开启或关闭状态及隔离逻辑降低其功耗.利用二项分布计算最佳冗余逻辑,引入成品率边界因子判定冗余逻辑的经济性.将优化的SRAM64K×32应用到SoC中,并对SRAM64K×32 的测试方法进行了讨论.该SoC经90nm CMOS工艺成功流片, 芯片面积为5.6mm×5.6mm, 功耗为1997mW.测试结果表明:优化的SRAM64K×32 在每个晶圆上的成品率提高了9.267%,功耗降低了17.301%.  相似文献   
84.
为消除锅炉因煤质差频繁熄火对电厂经济效益的影响,实现充分利用蓄热保持机组不解列,达到迅速恢复点火并充分保证设备安全性的目的.贵溪发电有限责任公司对2×300 MW机组机炉联锁方案进行改造,增加主蒸汽过热度保护逻辑.同时对MFT动作信号联锁逻辑进行优化.改造后两台机组因锅炉熄火引起的非计划停运大幅减少,同时节省大量燃油,且能够充分保证机组安全性,实施效果较好.实践证明,该改造方案能够在保证机组安全的情况下创造较好的经济效益,可以给同类型机组以借鉴.  相似文献   
85.
吴长才  刘冬根 《宽厚板》2008,14(6):26-27
本文介绍西门子6RA70直流调速装置的调速实现及在中板三辊轧机压下中的应用.  相似文献   
86.
研究蜂蜡对大豆分离蛋白/羧甲基纤维素复合材料性能的影响。当蜂蜡添加量增加,复合材料的颜色变黄;透明度、水蒸气透过率和断裂伸展率降低,氧气透过率升高。   相似文献   
87.
88.
Apolipoprotein B (ApoB) plays a crucial role in lipid and lipoprotein metabolism. The effects of APOB locus variants on lipid profiles, metabolic syndrome, and the risk of diabetes mellitus (DM) in Asian populations are unclear. We included 1478 Taiwan Biobank participants with whole-genome sequence (WGS) data and 115,088 TWB participants with Axiom genome-wide CHB array data and subjected them to genotype–phenotype analyses using APOB locus variants. Five APOB nonsynonymous mutations, including Asian-specific rs144467873 and rs13306194 variants, were selected from participants with the WGS data. Using a combination of regional association studies, a linkage disequilibrium map, and multivariate analysis, we revealed that the APOB locus variants rs144467873, rs13306194, and rs1367117 were independently associated with total, low-density lipoprotein (LDL), and non-high-density lipoprotein (non-HDL) cholesterol levels; rs1318006 was associated with HDL cholesterol levels; rs13306194 and rs35131127 were associated with serum triglyceride levels; rs144467873, rs13306194, rs56213756, and rs679899 were associated with remnant cholesterol levels; and rs144467873 and rs4665709 were associated with metabolic syndrome. Mendelian randomization (MR) analyses conducted using weighted genetic risk scores from three or two LDL-cholesterol-level-associated APOB variants revealed significant association with prevalent DM (p = 0.0029 and 8.2 × 10−5, respectively), which became insignificant after adjustment for LDL-C levels. In conclusion, these results indicate that common and rare APOB variants are independently associated with various lipid levels and metabolic syndrome in Taiwanese individuals. MR analyses supported APOB variants associated with the risk of DM through their associations with LDL cholesterol levels.  相似文献   
89.
A leaf structure with high porosity is beneficial for lateral CO2 diffusion inside the leaves. However, the leaf structure of maize is compact, and it has long been considered that lateral CO2 diffusion is restricted. Moreover, lateral CO2 diffusion is closely related to CO2 pressure differences (ΔCO2). Therefore, we speculated that enlarging the ΔCO2 between the adjacent regions inside maize leaves may result in lateral diffusion when the diffusion resistance is kept constant. Thus, the leaf structure and gas exchange of maize (C4), cotton (C3), and other species were explored. The results showed that maize and sorghum leaves had a lower mesophyll porosity than cotton and cucumber leaves. Similar to cotton, the local photosynthetic induction resulted in an increase in the ΔCO2 between the local illuminated and the adjacent unilluminated regions, which significantly reduced the respiration rate of the adjacent unilluminated region. Further analysis showed that when the adjacent region in the maize leaves was maintained under a steady high light, the photosynthesis induction in the local regions not only gradually reduced the ΔCO2 between them but also progressively increased the steady photosynthetic rate in the adjacent region. Under field conditions, the ΔCO2, respiration, and photosynthetic rate of the adjacent region were also markedly changed by fluctuating light in local regions in the maize leaves. Consequently, we proposed that enlarging the ΔCO2 between the adjacent regions inside the maize leaves results in the lateral CO2 diffusion and supports photosynthesis in adjacent regions to a certain extent under fluctuating light.  相似文献   
90.
Due to the rapid development of the miniaturization and portability of electronic devices, the demand for polymer composites with high thermal conductivity and mechanical flexibility has significantly increased. A carbon nanotube (CNT)-graphene (Gr)/polydimethylsiloxane (PDMS) composite with excellent thermal conductivity and mechanical flexibility is prepared by ultrasonic-assisted forced infiltration (UAFI). When the mass ratio of CNT and Gr reaches 3:1, the thermal conductivity of the CNT-Gr(3:1)/PDMS composite is 4.641 W/(m·K), which is 1619% higher than that of a pure PDMS matrix. In addition, the CNT-Gr(3:1)/PDMS composite also has excellent mechanical properties. The tensile strength and elongation at break of CNT-Gr(3:1)/PDMS composites are 3.29 MPa and 29.40%, respectively. The CNT-Gr/PDMS composite also shows good performance in terms of electromagnetic shielding and thermal stability. The PDMS composites have great potential in the thermal management of electronic devices.  相似文献   
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