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231.
232.
AnDing Wang MingXiao Zhang JianHua Zhang He Men BaoLong Shen ShuJie Pang Tao Zhang 《科学通报(英文版)》2011,56(36):3932-3936
The effect of Ni addition on the glass-forming ability (GFA) and soft-magnetic properties of an (Fe1-xNix)75.5B14.5P7Nb3 (x=0-0.6) alloy system were investigated. We found that the addition of Ni was effective in allowing the alloy to approach a eutectic point as well as increasing the thermal stability of the supercooled liquid. By increasing the amount of Ni,the supercooled liquid region (ΔTx),the reduced glass transition temperature Trg (Tg/Tl) and the Y parameter [Tx/(Tg+Tl)] increased from 49 to 75 K,0... 相似文献
233.
在论述对等电子服务信誉激励领域研究科学意义的基础上,分别就对等系统服务质量(QoS)、信誉机制和信誉激励等方面的国外研究现状进行综述,并介绍了国内的相关研究情况,最后对本领域的遗存问题进行了总结.分析认为:对等电子服务信誉机制经过多年研究已经有了一定的进展,但还存在信任定义不一致、缺乏反馈激励、信任模型安全性差、信任模型实现复杂度高等问题亟待解决;因此,对等电子服务QoS评价模型、融合QoS和奖惩措施的双向信任模型、信任模型安全性保证等问题是今后研究的重点和主要方向. 相似文献
234.
Bioaerosol charge information is of vital importance for their electrostatic collection. Here, electrostatic means and molecular tools were applied to studying bioaerosol charge dynamics. Positively or negatively charged bioaerosols were collected using an electrostatic sampler operated with a field strength of 1.1 kV cm 1 at a flow rate of 3 L min 1 for 40 min. Those with fewer or no charges bypassing the sampler were also collected using a filter at the downstream of the electrostatic sampler in one environment. The experiments were independently conducted three times in three different environments. The collected bacterial aerosols were cultured directly on agar plates at 26°C, and the colony forming units (CFU) were manually counted. In addition, the CFUs were washed off from the agar plates, and further subjected to polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) for culturable diversity analysis. The results revealed remarkable differences in positively and negatively charged culturable bacterial aerosol concentration and diversity among the studied environments. In the office environment, negatively charged culturable bacterial aerosols appeared to dominate (P = 0.0489), while in outdoor and hotel environments both polarities had similar concentration levels (P = 0.078, P = 0.88, respectively). DGGE patterns for positively charged culturable bacterial aerosols were shown strikingly different from those of negatively charged regardless of the sampling environments. In addition, for each of the environments positively charged culturable bacterial aerosols collected were found to have more band pattern similarity with those positively charged for respective regions of agar plates than those negatively charged, and vice versa. The information developed here is useful for developing efficient electrostatic sampling protocols for bioaerosols. 相似文献
235.
目前施工企业并没有把安全管理放到重要位置,只注重效益.然而没有安全就没有效益.文章论述了安全管理与施工企业的关系及重要性,旨在明确抓好安全管理,以引起同行的重视. 相似文献
236.
We review recent progress in studying silicate, carbonate, and metallic liquids of geo-logical and geophysical importance at high pressure and temperature, using the large-volume high-pressure devices ... 相似文献
238.
山西作为能源大省,一直是中国对外经济活动的活跃力量.但是,近年来,随着对外合作的加深,也体现出一些制约因素,最主要体现在缺乏精通国际商务的高素质人才.从制约人才引进和培养的角度出发,客观分析造成山西国际商务人才现状的原因,并提出相应的对策. 相似文献
239.
<正>Many studies have shown that knowledge resources have been the real source of innovation and competitiveness of real estate enterprises.Therefore,it is the basic work to establish the real estate enterprise knowledge resources framework for implementing knowledge management(KM),and it should be given enough attention.A sort of the real estate enterprise knowledge resources framework system has been built in this paper based on the thought of Clark Henderson' s enterprise knowledge classification,and the contents have been analyzed and expounded.Thus,the real estate enterprises can grasp clearly the basic contents of its knowledge resources,then depict the knowledge system,in the end the solid foundation should be settled for implementing knowledge management. 相似文献
240.
Variable supply voltage-clustered voltage scaling (VS-CVS) scheme can be very effective in reducing power consumption of CMOS circuits without degrading system performance. Level converting flip-flops (LCFFs) are key elements in the CVS scheme. In this paper, a new explicit-pulsed double-edge triggered level converting flip-flop (nEP-DET-LCFF) is proposed, which employs double-edge triggering technique, dynamic structure, explicit pulse generator,conditional discharge technique and proper arrangement of stacked nMOS transistors to efficiently perform latching and level converting functions simultaneously. The proposed nEP-DET-LCFF combines merits of both conventional explicit-LCFFs and implicit-LCFFs. Simulation shows the proposed nEP-DET-LCFF has improvement of 19.2%~46% in delay, and 19.4%~52.9% in power-delay product (PDP) as compared with the published LCFFs. 相似文献