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931.
Preincubation of blood from normal human volunteers with epinephrine significantly decreased the granulocytes ability to adhere to nylon fibres. Possible significance for the in vivo correlation is discussed. 相似文献
932.
Copper microelectrodes were used in microvoltammetry to detect histamine and several amino acid neurotransmitters. High sensitivity
was obtained through the use of copper microelectrodes, and detection limits of 50 nmol/L and 90 nmol/L were obtained for
histamine and histidine, respectively. Furthermore, histamine and several amino acids neurotransmitters were firstly separated
and detected by capillary electrophoresis with amperometric detection on copper microelectrodes. Mass limits of 490 amol and
440 amol were achieved for histamine and histidines, respectively, by using this mothod.
Supported by the National Natural Science Foundation of China
Hu Shen: born in 1970, Ph. D. 相似文献
933.
The novel chitosan microspheres grafted with β-cyclodextrins (CMGC) were prepared by means of the reaction of chitosan microspheres
and mono-(6-p-tosyl)-β-cyclodextrins (β-CD-OTs-6). β-CD-OTs-6 were gained by the reaction ofp-toluenesulfonyl chloride (TsCl) and β-cyclodextrins (β-CDs). Their structures were proved by Fourier transform infrared spectral
analysis (FT-IR), X ray powder diffraction analysis, and13C NMR; the configuration of CMGC was characterized by scanning electron micrograph (SEM) and transmittance electron micrograph
(TEM). The inclusion complex of CMGC with iodine was prepared and its inclusion ability was studied. The experimental results
showed that some iodine was included with CMGC and formed a stable inclusion. The stable complex of CMGC and iodine (CMGC-I)
shows good antibacterial effect.
Foundation item: Supported by the State Educational Committee Doctoral Foundation of China(2000048615)
Biography: YI Ying (1964-), female, Associate professor, Ph. D candidate, research direction: synthesis of friendly environmental material. 相似文献
934.
通过对不同分梳辊型式及转速条件下,转杯纺成纱质量的对比实验,分析了转杯纺纱机的分梳辊型式及其转速对分梳质量的影响。指出:分梳辊的型式对成纱强力、条干均匀度影响显著,在相同速度条件下,针辊的分梳效能优于锯齿辊。 相似文献
935.
1. INTRODUCTIONUNIX has been widely used in various areas such as buSiness and indwtrial world. With the developmentof computer applications, real-time computation becomes a challenging research area. The real-take UNIX isdemanded because many real,thae applications have been develOPed on the Platform Of UNIX. The dgoaJ of real-take UNIX is providing the real-time applications with a real-time OPerating system, which hashigh performance, safety and the function of schedulebility … 相似文献
936.
937.
根据小半径曲线防磨护轨的结构特点,采用三维块单元建立有限元分析模型,并对原始设计进行分析计算,结果为应力集中较大。在对应力及变形分析基础上提出了结构的改进设计方案。通过有限元分析计算表明,改进后的设计方案应力分布趋于均匀,并有可靠的机械强度。 相似文献
938.
庞雅丽 《北京师范大学学报(自然科学版)》2005,41(2):115-118
研究了Bernstein-Gelfand-Ponomarev反射函子在带自同构σ的箭图Q的F-稳定表示上的作用,并证明了当Q是Dynkin图时,存在一个从Q的不可分解F-稳定表示的同构类到(Q,σ)对应的赋值图的正根的双射. 相似文献
939.
A fuzzy rule based genetic algorithm and its application in FMS 总被引:2,自引:0,他引:2
LiShugang WuZhiming PangXiaohong 《高技术通讯(英文版)》2005,11(1):56-60
Most of the FMS (flexible manufacturing systems) problems belong to NP-hard (non-polynomial hard) problems. The facility layout problem and job-shop schedule problem are such examples. GA (genetic algorithm) is applied to get an optimal solution. However, traditional GAs are usually of low efficiency because of their early convergence. In order to overcome the shortcoming of the GA a fuzzy rule based GA is proposed, in which a fuzzy logical controller is introduced to adjust the value of crossover probability, mutation probability and crossover length. The HGA (hybrid genetic algorithm), which is integrated with a fuzzy logic controller, can avoid premature convergence, and improve the efficiency greatly. Finally, simulation results of the facility layout problem and job-shop schedule problem are given. The results show that the new genetic algorithm integrated with fuzzy logic controller is excellent in searching efficiency. 相似文献
940.
固体缓释剂保鲜荔枝效果研究 总被引:2,自引:0,他引:2
采用缓慢释放SO2,CO2气体方法保鲜荔枝,结果表明。在常温下,采用缓释剂a处理效果最好,好果率在80%以上;在24℃的冷藏条件下,采用缓释剂b处理,效果最好,贮藏60d后,好果率为90.1%,a,b两种处理SO2残留都未超标。 相似文献