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461.
韩仁山 《山西科技》2007,(4):116-117
文章针对矿山机电传动设备的高可靠性要求,基于CSCW的理论和方法,提出了一种新的故障监测和诊断系统的结构模式:将故障监测技术、诊断技术揉为一体,采用多传感器+单片机+PLC+上位机的模式构置故障诊断系统的硬件环境。  相似文献   
462.
合成了金刚烷胺水杨醛Schiff碱配体(C17H21NO,以HL表示)与5种过渡金属(Ⅱ)的新的配合物[MCl2(HL)2](M=Mn(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)、Cd(Ⅱ)),用元素分析、摩尔电导、红外光谱、1H NMR谱和热重分析对产物进行了表征;讨论了配体与中心金属离子的键合情况,并推测了配合物的结构.根据表征结果和参考文献得出:每一配合物的中心金属离子与2个Schiff碱配体中的酚羟基氧及2个氯离子发生配位,配位数为4.  相似文献   
463.
用化学还原法合成了Fe(Pd)P合金颗粒,详细考察了反应温度、溶液的pH值、添加剂、反应物料比以及引发剂等因素对反应速度、产率以及磷含量的影响,选择了适宜的合成条件.  相似文献   
464.
The effect of carboxymethytl pachymaram (CMP) on the function of dendritic cells(DCs) derived from spleens of hepatitis B virus transgenic mice are studied in vitro. The phenotypes of DCs are tested by flow cytometry (FCM), cytokines measured by ELISA. The expression of DCs’ phenotypes in HBV transgenic mice are low (CD80+CD11c+:59.12±11.53 vs 9.60±4.53, p<0.01; CD80+ MHC-II+: 44.86±12.31 vs 9.80±5.72, p<0.01, normal mice vs HBV transgenic mice), the ability of DCs stimulating T lymphocytes proliferation decreases (0.37±0.11 vs 0.20±0.11, p<0.05, normal mice vs HBV transgenic mice), levels of IL-12 and IFN-γ decrease whereas the level of IL-10 increases; CMP can enhance DCs’ ability of stimulating T lymphocytes proliferation, facilitate the secretion of IL-12 and IFN-γ, inhibit the secretion of IL-10, thus up regulates DCs function. The results show a good prospective use of CMP on the treatment of chronic hepatitis B. Biography: HOU Anji (1963–), male, Ph.D. candidate, Associate professor, research direction: clinical virology.  相似文献   
465.
韩灵翠  张莉 《太原科技》2007,(12):42-43
结合化工学院基础化学实验中心创建“省级示范实验中心”的实践.全面阐述了硬、软环境以及队伍、教改、创新等各方面建设的有益经验和成效.为深化教学改革和提高实验教学质量发挥了重要作用。  相似文献   
466.
Microbial communities in microcosm soils treated with battery waste   总被引:1,自引:0,他引:1  
Battery waste is one of the most destructive hazards to our environment,especially to the soil.In order to understand the effects of the battery waste on the microbial communities in soil,microcosm soils were treated with the powder made from the battery waste.Microbial biomass and respiration were measured after 15,30,45,and 60 days of the treatment,and catabolic capability and Bi- olog profile were determined after 60 days.Microbial biomass was declined by all treatments,while microbial respiration and catabolic ca- pability were enhanced.Although microbial biomass recovered after a period of incubation,microbial respiratory quotient,catabolic capa- bility and community structure remained significantly affected.Our results also suggest that microbial respiratory quotient and Biolog pa- rameters are more sensitive than microbial biomass to the battery stress on bioavailability.  相似文献   
467.
Protein-protein interaction networks serve to carry out basic molecular activity in the cell. Detecting the modular structures from the protein-protein interaction network is important for understanding the organization, function and dynamics of a biological system. In order to identify functional neighbor- hoods based on network topology, many network cluster identification algorithms have been devel- oped. However, each algorithm might dissect a network from a different aspect and may provide dif- ferent insight on the network partition. In order to objectively evaluate the performance of four com- monly used cluster detection algorithms: molecular complex detection (MCODE), NetworkBlast, shortest-distance clustering (SDC) and Girvan-Newman (G-N) algorithm, we compared the biological coherence of the network clusters found by these algorithms through a uniform evaluation framework. Each algorithm was utilized to find network clusters in two different protein-protein interaction net- works with various parameters. Comparison of the resulting network clusters indicates that clusters found by MCODE and SDC are of higher biological coherence than those by NetworkBlast and G-N algorithm.  相似文献   
468.
For the encoding bit-rate problem in H.264 wireless video communication,this paper analyzes the bit-rate computation model and the Mean Square Error distortion model,establishes the relation between the quantization parameter of the encoding bit-rate and the intra frame refresh rate of the macro block,and put forward a new ideal about the coding rate on the basis of general binomial computation model theory. Furthermore,this method not only can adaptively adjust the bit allocation and quantization parameter and prevents buffer from overflowing downward or upward under given network bandwidth,but also can apply the rate-distortion to optimize the solution method,control the encoding bits accurately and optimizes the allocation between the intra and inter frame encoding macro block.  相似文献   
469.
The Rb-Sr isotopic dating of pyrite mineral from ore deposits can directly provide mineralization age. However, many geological factors may affect the Rb-Sr isotopic system,which baffles application of this method. Employing ultra-low procedural blank Rb-Sr method,we have dated pyrites separated from the No. 4 breccia pipe of the Qiyugou gold deposit,western Henan Province. Single grains of euhedral pyrite crystal with few microcracks yield an isochron age of 126 ± 11 Ma, which represents time of the main mineralization stage of the deposit. Pyrite grains of cataclastic type show nevertheless scattered Rb-Sr isotopic composition and no reasonable isochron can be defined. Crystal morphology and mineral inclusion studies reveal that Rb and Sr of pyrite mineral probably are preserved mainly in biotite, K-feldspar, and sericite mineral inclusions. The dating results likely suggest that cataclastic pyrite is not suitable for the Rb-Sr dating due to modification of the Rb-Sr isotopic system by later hydrothermal activity of fluid.  相似文献   
470.
先前研究表明,企业组织对关系收益的不同诉求是驱动企业选择其关系实践模式的关键性因素,但对于企业关系收益诉求的决定机制,并未提供系统性的考察与解释。针对这一问题,该文从新的视角详细界定了企业战略模式的四维度框架,详细考察了战略模式的不同维度对于企业对组织关系收益诉求的不同影响,构建起了战略模式和关系收益诉求决定机制间的作用路径。基于北京市高新技术产业集群的企业样本进行了相关实证分析。研究结果表明,企业战略模式的4个导向与企业3类组织关系收益诉求水平间具有显著的正相关关系。  相似文献   
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