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排序方式: 共有10000条查询结果,搜索用时 734 毫秒
991.
目的制备抗β-溶血性链球菌、G簇溶血性链球菌、金黄色葡萄球菌3种咽喉炎常见菌IgY抗体,并分析其特性。方法采用超声波破碎法将3种咽喉菌制备成可溶性抗原液,免疫产蛋母鸡,从鸡蛋黄中提取IgY抗体,应用免疫电泳、ELISA、SDS-PAGE检测抗3种咽喉菌IgY抗体的特性及热稳定性。结果抗原免疫母鸡10d后,鸡蛋黄中即有抗3种咽喉菌的IgY抗体产生,60d时抗体滴度高达1∶102400,IgY抗体滴度在室温可保持5~6个月不变。结论制备的抗3种咽喉菌IgY抗体滴度高,特异性强,稳定性好。 相似文献
992.
An experimental study has been performed in order to determine the effect of humidity on the flow field and the flame stability
limit in turbulent non-premixed flame. Two-dimensional Particle Image Velocimetry (PIV) measurements were made to quantify
the velocity field, with and without steam injected. The results indicate the addition of steam decreases the recirculation
flow and reduces the distance between the forward and aft stagnation points. The detailed stabilization regimes show that
the critical fuel-to-air velocity ratios of the central fuel penetration in the humid air case are 16% to 22% lower, and the
partially quenching limits are at least 25% lower. The decreased penetration limit is due to a reduction in momentum of the
humid air. An analysis of flamelet concepts reveals that increased chemical reaction time leads to lower partially quenching
limits in the humid air combustion. 相似文献
993.
Baoqing Deng Shanshan Kong Chang Nyung Kim 《Korean Journal of Chemical Engineering》2007,24(4):577-582
In this paper, a mathematical model is presented to describe the photocatalytic degradation of VOCs in a packed bed reactor.
Here, the adsorption of VOCs on the wall of the reactor is taken into account and the diffusion of VOCs in the axial direction
is neglected. First-order kinetics is used to describe the photocatalytic oxidation of VOCs. The analytical solution of the
present model is obtained by traveling wave method. The solution shows that the reactor performance is totally dependent on
the inlet concentration of VOCs when the time is large enough. The present model is validated through the experimental result
of the photocatalytic oxidation of trichloroethylene in a packed bed and the predicted results accord well with the experimental
data. The influence of flow rate and inlet concentration on the performance of the reactor is discussed in detail. High flow
rate offers high reaction rate and low conversion efficiency. The different inlet conditions and different reaction patterns
are also investigated. The model would be useful to estimate the rate constant and help to the design of the reactor. 相似文献
994.
Kronkanok Hongthong Kejvalee Pruksathorn Pornpote Piumsomboon Paiboon Sripakagorn 《Korean Journal of Chemical Engineering》2007,24(4):612-617
This research focuses on the effect of the geometry and patterns of the gas flow channel on the PEM fuel cell performance.
Simulation was conducted and the results were verified by experiments. Three-dimensional, single phase, compressible and isothermal
models of 5 cm2 electrodes, anode and cathode, were developed and studied by utilizing a commercial Computational Fluid Dynamics (CFD) software,
FLUENT 4.5. Two types of gas flow channel were investigated: conventional and interdigitated. The results showed that the
flow channel pattern does not have a significant effect on the anode cell performance, whereas it has a strong effect/influence
on the cathode cell performance. The interdigitated design provides a higher limiting current density and cell performance
than the conventional design on the cathode side. Moreover, the cell performance does not depend on the inlet and outlet channel
widths. On the contrary, for the interdigitated design, it was influenced by the shoulder width. Finally, experiments were
conducted to validate the simulation results. 相似文献
995.
β-sialon结合SiC复相材料的分相抗氧化行为 总被引:4,自引:1,他引:4
对粘土类原料碳热还原及氮化反应法合成的β-sialon结合SiC复相耐火陶瓷材料进行了不同氧化条件下的抗氧化性实验。研究表明:1300℃时的氧化过程在12h内为化学反应控制阶段,12h后为扩散控制阶段。扩散控制阶段反应符合Ginsterlinger扩散动力学关系。首次分别得到复合状态下的β-sialon基质相、SiC颗粒相及β-sialon结合SiC复合相在1300℃下的分相扩散控制型抗氧化反应动力学方程,从各相的扩散控制型反应级数确认了β-sialon基质相对SiC颗粒相的高温氧化保护作用以及复相材料具有的优异抗高温氧化性能。 相似文献
996.
近年来,Intranet不断飞速发展,导致信息量趋于庞大。于是如何让用户查找到自己想要的信息成为Intranet搜索引擎的一个难题。关于这个问题,它将对几种经典的Intranet搜索排序算法进行分析、比较。希望在以后的开发中可以以它为参照,进行相关算法的改进,尽可能的让算法更接近完美,使搜索结果更能符合用户的需求。 相似文献
997.
因为制冷设计不合理,施工不专业,都会影响数据中心机房的制冷效率。该文介绍三种数据机房的高效制冷方法:按需制冷;水平送风;封闭冷通道。研究数据机房的高效制冷,不仅是节能减排的需要,也是保障数据机房稳定运行的需要。 相似文献
998.
在ad hoc网络中,节点间的合作是一个重要的问题,不相邻节点的信息传递只能依靠中间节点的转发来完成,若中间节点存在自私行为则会较大地影响网络的性能。节点自私类型有不同,对网络功能造成的影响也各不一样,有些自私节点在一定数量上对网络整体性能影响不大,可以容忍;而有些自私节点则必须得采取强硬的惩戒措施,将其驱逐出网络或降低它的信誉值并公布。该文采用基于信誉值的算法检测出ad hoc网络中的问题节点,并对其进行类型定义,仿真查看其对网络性能的影响,方便下一步根据不同自私节点进行机制设计。 相似文献
999.
Iván Jachmanián Lucía Margenat Ana I. Torres Maria A. Grompone 《Journal of the American Oil Chemists' Society》2007,84(6):597-601
The solubility of different ethyl esters derivatized from hake liver oil in supercritical carbon dioxide was studied. A selectivity
factor was used to determine optimal conditions to fractionate the ethyl ester mixture. A strong influence of solvent pressure
and temperature was observed within 8.63–18.04 MPa and 40–70 °C. The lowest total solubility of the ethyl ester mixture was
obtained when using supercritical carbon dioxide at the lowest density (the lowest pressure and the highest temperatures value
tested). The highest discrimination against long-chain polyunsaturated fatty acids (e.g. EPA and DHA) was also obtained at
these above conditions. Conversely, higher solubility and lower selectivity were obtained when solvent density increased.
Considering this inverse correlation between selectivity and solubility, a single-step batch-fractionation process was designed
to increase the 22:6 ethyl ester content from an initial value of 17.5% in the starting material to 55% in the final extract. 相似文献
1000.
Min-Jae Yoon Yoan-Sang Bae Sang-Ha Son Jae-Wook Lee Chang-Ha Lee 《Korean Journal of Chemical Engineering》2007,24(5):877-880
Luminescent yttrium aluminum garnet (YAG, Y3Al5O12) nanoparticles doped with Eu (10 at%) were synthesized in batch-type and continuous-type supercritical water (SCW) reactors.
In the case of the continuous-type SCW method, the particles of YAG: Eu phosphors were much smaller and demonstrated a uniform
spherical-like shape. Inversely, in the case of the batch-type SCW method, a needle-like or elliptical-like shape was formed
because a finite amount of time was required to reach SCW conditions from ambient conditions. However, the emission intensity
of YAG: Eu phosphors synthesized by using the batch-type SCW method was stronger. Therefore, it is concluded that the continuous-type
SCW method is superior to the batch-type SCW method from the viewpoint of the particle size and shape, but the luminescence
property of phosphors in the continuous-type SCW method needs to be improved. In addition, a calcination process slightly
improved the luminescence intensities of YAG: Eu phosphors generated by using either the batch-type or continuous-type SCW
methods. 相似文献