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51.
It has been stated that boiled for three hours haemocytocardiotoxin (HT) from cobra poison loses "direct" hemolytic activity and is unable to potentiate a haemolytic effect of phospholipase A. Surface activity of HT does not change. It is shown that in the course of heat denaturation the aggregation of toxin molecules to dimers and trimers takes place and electrophoretic mobility is decreased. The fluorescence of HT tyroxin residues supported the fact of its irreversible heat denaturation.  相似文献   
52.
Future high-performance computing (HPC) architectures will consist of whole parallel computing systems integrated on chip-level and boards mounted with lots of computing chips and chip-external main memory. Photonic networks on board and photonic network on chips (NoCs) offer the potential to fulfill the high bandwidth requirements in such systems. In addition they need less power, offer better EMC capabilities and can reduce cabling effort compared to electronic networks. Due to their non-blocking property Clos networks are frequently used in HPC architectures. Therefore we investigated how a photonic on-board Clos network can be realized using Coarse Wavelength-Division-Multiplexing (CWDM) techniques with state-of-the art components based on fiber technology. In addition we present a new photonic Clos NoC architecture based on Wavelength Interchanging (WI) elements, optical waveguide structures, mode-locked laser sources, nanophotonic microrings and passive optical deflection elements to reduce the number of switches. We discuss the benefits and drawbacks for using different optical technologies for such an architecture.  相似文献   
53.
Nitrous oxide produced a dose-related "analgesia" in mice (median effective dose, 55 percent). The analgesia was evaluated by means of a phenylquinone writhing test. Narcotic antagonists or chronic morphinization reduced nitrous oxide analgesia. Either nitrous oxide releases an endogenous analgesic or narcotic antagonists have analgesic antagonist properties heretofore unappreciated.  相似文献   
54.
This paper proposes a control method to the magnet flux in an interior permanent-magnet (IPM) motor following short-circuit-type faults in either the inverter drive or motor stator windings. Phase-based control is employed to implement the flux-ing-control method so that it is possible to take advantage of a zero-sequence current in order to minimize the current in the shorted phase. It is shown that phase-based control results in a smaller induced current than when employing a synchronous-frame dq0 current regulator. The induced torque is also less than that when employing a purposely commanded symmetrical short circuit in response to a short-circuit-type fault. In the paper, the complete magnet-flux-ing-control algorithm is derived with reference to the proposed phase-current-control method. The impact of controlling the zero-sequence current on the resulting phase currents is presented. Both simulation and experimental results are presented, verifying the operation of the proposed methods.  相似文献   
55.
阐述了电容式电压互感器的各种阻尼器的优缺点,并对速饱和阻尼器设计进行了详述,提出了CVT设计速饱和阻尼器应注意的事项。  相似文献   
56.
大型真空冶金系统 (DVMS)的故障点多、故障现象与故障原因间对应关系复杂 ,很难从抽气机理上来精确地进行故障诊断。DVMS工艺要求能对该设备进行快速、准确的故障诊断。为此 ,介绍了一种基于模糊聚类算法的智能诊断模型。该模型具有很强的自学习、自组织能力 ,适用于大型复杂真空系统的故障诊断。以RH KTB真空冶金系统的智能故障诊断为例 ,给出了真空冶金系统模糊故障诊断的实际过程。通过分析证实了该算法对大型复杂真空冶金系统智能故障诊断的有效性  相似文献   
57.
烟草销售企业供应链系统分析与设计   总被引:3,自引:0,他引:3  
随着现代信息技术的发展,现代企业之间的竞争不再是单一企业之问的竞争,而是企业供应链之间的竞争,供应链管理可以将核心企业内外部资源统筹优化配置,扩展资源配置范围,同时也可以最大限度地消除中间环节,节省交易费用.在分析了中国烟草销售企业特点的基础上,针对烟草销售企业存在的问题,应用供应链的思想,进行系统设计,最后以深圳烟草公司供应链系统为例,对烟草销售企业供应链系统功能、结构及系统关键技术进行了说明.  相似文献   
58.
Two experiments were conducted to study the effects of methionine supplementation on ruminal fermentation and digesta kinetics. In Exp. 1, nine ruminally cannulated beef heifers (average initial BW = 527 kg) in a crossover design were fed low-quality grass hay and cottonseed meal with or without 11.4 g of supplemental methionine (polysaccharide-coated). Particulate and fluid kinetics, rate of DM and NDF disappearance, ruminal VFA and NH3 N concentrations, and pH were not altered (P > .10) by supplemental methionine; however, ruminal purine concentration was greater (P < .05) in methionine-supplemented heifers than in unsupplemented heifers. In Exp. 2, 12 ruminally cannulated Holstein steers (average initial BW = 622 kg) grazing a fescue pasture were allotted to one of three groups: no supplemental methionine (CON) or 11.4 g of supplemental methionine fed at 0700 (AM) or at 1200 (PM). Forage intake, particulate kinetics, ruminal fluid kinetics, pH, VFA, and NH3 N concentrations were not altered (P > .10) by supplemental methionine or supplementation time. In situ rate of DM and NDF disappearance was greater (P < .05) in supplemented steers than in CON steers; AM steers exhibited faster (P < .05) rates than PM steers. Overall, methionine supplementation of low-quality forage increased ruminal purine concentration but did not alter in situ fermentation or digesta passage, whereas supplementation at 0700, but not at 1200, of steers grazing fescue forage increased rate of NDF fermentation.  相似文献   
59.
60.
本文简要介绍了采用国产碲锌镉(CdZnTe)单晶材料制备的CdznTe核辐射探测器工艺及测试结果.对α带电粒子Thc-c/(6.04MeV、8.78MeV)FWHM=2.O%、241 Am(5.486MeV)FWHM=2.3%,137Cs低能7(662keV)FWHM=9.7%和207Bi(1048.1keV、975.6keV)内转换电子所测定的能谱.  相似文献   
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