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971.
The Gell-Mann and Low's technology and Bethe-Salpeter equation for manyparticles are first discussed. Then the space-like form of Bethe-Salpeter equation involving both the bound state and scatter state are extended to many-particle case. Consequently we build the formalism of the space-like equation with explicit Lorentz covariant form and without the difficulty of ghost states automatically. 相似文献
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975.
Marlon M. Reis Pedro H. H. Araújo Claudia Sayer Reinaldo Giudici 《Macromolecular rapid communications》2003,24(10):620-624
This work describes the estimation of polymer particle size from NIR spectra collected in situ and online in an automated reactor. A good linearity between spectra and average polymer particle diameter is found. The multivariate linear model is also tested with an independent data set not used in the model fitting. Despite varying monomer and polymer concentrations and temperature changes along the process, the average particle sizes are well predicted and can be monitored by NIR spectroscopy during emulsion polymerization reactions.
976.
《Particuology》2023
Due to a higher operating temperature (≥800 °C), Solar Particle Receiver (SPR) which uses particles as the working medium is considered as one of best candidates to improve the thermoelectric conversion efficiency of concentrating solar power plants. In this paper, a quartz tube solid particle receiver model is fully developed by using the discretized lumped parameter method, in which the calculation process of particle temperature and thermal loss is clearly given. In order to improve the manipulation level of particle receiver during the operation, the dynamic characteristics of the quartz tube particle receiver are comprehensively studied by the disturbance test of selected input parameters. Besides, in order to grasp the influence rule of key parameters on the thermal performance of particle receiver, the key parameters’ sensitivity analysis is also deeply studied. The results show that the particle outlet temperature can reach as high as 810 °C under a relatively small value of solar flux 600 kW/m2, but the receiver efficiency is only about 75%; Besides, the receiver efficiency shows a variation tendency that it rises first falls afterwards with the increase of incident solar flux. The validity of proposed model is verified by a heating experimental system with a single quartz tube, and the relative error is not more than 7.9%. The research results are beneficial for understanding the dynamic characteristics and designing the particle receiver. 相似文献
977.
《Particuology》2023
Janus particle is a research hotspot due to its novelty and settlement in acid liquid during wastewater treatment. Heat and mass transfer mechanisms of Janus particle sedimentation considering corrosion are numerically investigated based on immersed boundary lattice Boltzmann method. Chemical reaction heat ratio, Damkohler number, Peclet number, and particle number effects on temperature field, concentration field, Janus particle mass reduction, position, and velocity are investigated. The uniform particle has an equilibrium position of about 1/4 times the channel width for two corroded uniform particle settlement processes. The Janus particle horizontal position deviates from the uniform particle equilibrium position due to the force caused by nonuniform buoyancy and particle rotation. When the chemical reaction heat ratio is more than 1, the Janus particle horizontal position is closer to the channel centerline and has a positive deviation. However, the converse trend happens when the chemical reaction heat ratio is less than 1, and the Janus particle horizontal position has a negative deviation. The Janus particle horizontal position deviation magnitude increases with increasing Damkohler number and decreasing Peclet number. The horizontal position deviation phenomenon exists for the single corroded Janus particle and two corroded Janus particle settlement processes. 相似文献
978.
利用电动态平衡技术,将单个带电煤颗粒悬浮在样品池中,可以实现煤颗粒燃烧过程的原位微观研究。本文简要介绍了电动态平衡技术的原理和相关的操作方法,总结了该技术应用于煤燃烧研究的进展,进一步探讨了结合时间分辨光谱技术研究煤燃烧物理化学过程细节的可行性与发展前景。目的在于向国内研究者介绍这一新技术并激发更多的研究兴趣。 相似文献
979.
在自然环境与工业领域中,颗粒材料是一种常见的缓冲材料,其中大量形态各异的非球形颗粒表现出复杂的力学特性并应用于不同工程领域。本文采用球谐函数构造不同球面度和表面凹凸特性的非规则颗粒,通过水平集方法计算球谐函数颗粒间的接触点和碰撞力,并对冲击过程中球形和凹形颗粒的缓冲性能进行离散元分析。数值结果表明,颗粒床厚度、冲击速度和颗粒形状显著影响球谐函数颗粒材料的缓冲性能。颗粒床底部的冲击力峰值随着颗粒床厚度和表面凹凸性的增加而降低,同时冲击力峰值随着冲击速度和颗粒球面度的增加而增加。与球形颗粒相比,球谐函数颗粒具有凹凸表面和多接触点特性,这有利于冲击荷载向四周扩展并提高凹形颗粒的缓冲效果。 相似文献
980.
纳米金修饰玻碳电极固载抗体电位型白喉类毒素免疫传感器的研究 总被引:6,自引:0,他引:6
将巯基乙胺 (AET)固载到玻碳电极 (GCE)表面 ,进而化学吸附纳米金 (NG) ,并通过半胱氨酸 (Cys)用戊二醛 (GA)作交联剂将白喉抗体 (anti Diph)固定在玻碳电极上 ,从而制得高灵敏电位型白喉类毒素 (Diph)免疫传感器 .通过循环伏安法考察了电极表面的电化学特性 ,并对该免疫传感器的性能进行了详细的研究 .该传感器对白喉类毒素检测的线性范围是 2 4~ 60 0ng·mL-1,斜率为 3 8.9mV/decade ,线性相关系数为 0 .9979,检出限为 5 .2ng·mL-1,并将其用于生物制品中白喉类毒素的检测 ,其结果令人满意 相似文献