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71.

以SCIE数据库为资料来源,统计1998-2005年蛋白质组学研究 论文的高产国家、机构、发表论文期刊及文献主题等相关指标,揭示蛋白质组学的研究现状 ,并对论文数量和影响力进行比较,以衡量我国在蛋白质组领域的研究实力。

  相似文献   
72.
Taking the extended Mindlin solution of a vertical point load acting in the interior of a multi layered elastic medium as the basic solution, an indirect boundary element method (BEM) was adopted to analyze pile foundations embedded in a multi layered elastic soil. The numerical analysis was carried out by the compiled program for a pile foundation in an homogeneous soil and a pile foundation in a multi layered soil. Reasonably good agreement is obtained between the present and existing solutions. Compared with the FEM software ABAQUS, the computational speed of BEM is much faster than that of FEM. Applying BEM in practice is convenient. It is pointed out that the exact measurement of elastic modulus is the key factor for applying BEM in geotechnical engineering.  相似文献   
73.
To solve the key problems of the electric drive system, a controller area network(CAN) based electric drive system for electric vehicles was designed. The system was composed of two parts: a CAN communication module and a motor control module. The newest transceiver (TJA1040) and a stand alone CAN controller were used during the design of the CAN communication module, and anti jamming measures were employed to guarantee communication stability. The fuzzy vector control method and direct speed control were applied to realize highly robust control functions. This system has high compatibility. It can be installed in electric vehicles as an independent module and be extended through CAN Bus.   相似文献   
74.
Methods of IF difference detection combined with rapid acquisition synchronization and tracking principle by parallel processing methods were proposed in order to quickly achieve synchronous digital capture and tracking in π/4 DQPSK demodulation.Field program grid array (FPGA) technology to achieve rapid detection of synchronous capture and symbol tracking was adopted by using the improved algorithm in parallel with signal acquisition and frequency offset acquisition. This adoption took into account the characteristics of π/4 DQPSK and was in accordance with the detection of rapid acquisition synchronization and the tracking principle. The experimental results show that clock synchronization signals can be restored stably in eight symbol bit, accurately realize bit timing, and possess strong anti interference capability without affecting frequency differences. This proposed algorithm is suited for frequency hopping communication systems with high transmission rates.  相似文献   
75.
Three typical commercial buildings in Chongqing, P.R. China were selected to study the actual summertime operation and energy situations of heating ventilating and air conditioning (HVAC) systems in commercial buildings. Based on tests of energy consumption of HVAC systems in these three buildings, we analyzed the electricity consumption of the main components of the air conditioning systems. The energy efficiency of the chillers and air conditioning water distribution systems were studied. The indoor thermal environment in these three buildings were also tested and discussed. It is concluded that problems exist in the air conditioning systems of commercial buildings. Among the problems are over sized system design, low equipment operating efficiencies, poor operation management, and lack of indoor temperature controls. To reduce energy consumption of HVAC systems in commercial buildings, we propose energy efficient strategies such as sizing systems based on accurate load calculation and automatic control under partial load conditions.  相似文献   
76.
葡萄酒香气成分萃取中固相微萃取纤维的选择   总被引:1,自引:0,他引:1  
【目的】针对葡萄酒香气成分气相色谱分析的要求,比较了3种固相微萃取纤维萃取葡萄酒香气成分的效果。【方法】选用常用的PA、PDMS/DVB、PDMS 3种固相微萃取纤维进行葡萄酒香气成分的富集、浓缩处理,然后用GC-MS检测香气成分。通过对不同固相微萃取纤维萃取香气成分的数量、化学种类以及各类化合物累积峰面积标准化值的比较,评价供试固相微萃取纤维萃取葡萄酒香气成分的效果。【结果】3种固相微萃取纤维萃取出的葡萄酒香气成分中,高级醇、化学酯和有机酸是主要成分,萜烯醇、β-大马酮、挥发性酚和呋喃酮等是微量成分。不同固相微萃取纤维萃取的化合物存在明显差异,PA萃取出化合物49种,PDMS萃取出53种,PDMS/DVB仅萃取出38种。累积峰面积标准化值分析表明,PA萃取高级醇、有机酸、3-甲硫基-1-丙醇、2(3H)-二氢呋喃酮、2,4-二季丁基苯酚的灵敏度高;PDMS萃取化学酯类、萜烯醇和β-大马酮的灵敏度高;PDMS/DVB几乎萃取各类化合物的灵敏度都低。【结论】在供试的3种固相微萃取纤维中,PDMS是萃取富集绝大多数葡萄酒挥发性成分的最佳纤维。  相似文献   
77.
通过对网络医学学术信息资源的分类及其评价分析,提出建立 网络医学学术信息资源检索导航系统的初步设想,帮助用户提高对网络医学学术信息资源 的甄别与应用能力。  相似文献   
78.

以Web of Science网络数据库中2007年的生物信息学文献为源文献,对高频被引论文进行同被引聚类分析,同时应用多维标度技术获得同被引论文的二维散点图,〖XD〗结合生物信息学和情报学知识总结该领域的学科结构和研究热点。

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79.
本研究探讨解决周口市玉米单作产量低,效益少,大豆种植面积较少的问题,夏玉米大豆同穴混作是解决这一问题的有效途径。  相似文献   
80.
2019年草地贪夜蛾灯诱监测应用效果   总被引:3,自引:0,他引:3  
2019年草地贪夜蛾灯诱结果,广西、湖南、湖北、河南、陕西、山西、宁夏、天津8省(区、市)14个高空测报灯观测点,6月始灯下陆续见蛾,8月-10月多数观测点出现明显蛾峰; 湖北、河南、天津3省(市)8个常规测报灯观测点7月-10月灯下见蛾,9月下旬和10月上旬出现蛾峰。因此,高空测报灯可用于草地贪夜蛾区域性种群动态监测,种群超过一定数量条件下常规测报灯有效,灯具需选择合适地点设置。多数高空测报灯下雄蛾量明显高于雌蛾量,常规测报灯雌雄比差异不大,其原因有待深入研究。  相似文献   
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