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101.
In order to improve the particle collection efficiency of the electrostatic precipitator (ESP), a transverse plate ESP with bipolar discharge electrodes is proposed. The simulations of the velocity distribution have shown that when the inlet velocity is 1 m/s, within the range of 40 mm from electrode plate, the average velocities of windward side and leeward side are less than 0.7 m/s and 0.3 m/s respectively. It is clear that the velocity near the collection electrode plate of this bipolar ESP is much lower than that of the ordinary ESP at the same inlet velocity. This low velocity can lead to higher efficiency for fine dust collection due to the less dust re-entrainment in ESP. It is also found that the average velocities are getting lower when the distance between plates electrodes are greater than 150 mm in accordance with the simulations. The voltage current characteristics of the bipolar ESP are superior to the ordinary ESP. The pressure drop of the bipolar ESP is about 30% higher than that of the ordinary one. The dust penetration of the bipolar ESP is about 54% less than that of the ordinary ESP when the sintering dust with 25.405 μm mass median diameter is used as the test particulate under the condition of the electric field from 2.1 kV/cm to 3.2 kV/cm and the velocity from 1.0 m/s to 1.5 m/s. 相似文献
102.
介绍了一种车用单刀双掷开关质量检测仪器的研发,包括检测系统的硬件设计、检测原理以及算法软件开发。首先,根据单刀双掷开关的工作原理及质量检测要求,开发了检测手指触觉压力的机械装置,以及控制开关通道切换的继电器控制电路;在此基础上,开发了相应的检测算法,可实现对开关切换状态、电压差以及手指触觉压力进行自动化的数据采集、分析、检测和判断,从而挑选出合格的开关;最后,设计了触屏人机交互界面,可实时显示产品检测的参数。该检测设备在某自动化生产线上经过近一年时间的检测验证,证明系统运行平稳,检测效果良好、误检率低,可以完全取代传统的人工检测方式,提高了开关的检测效率,降低了检测人员的工作量。 相似文献
103.
Toshiki Yoshizawa Michika Onoda Takeshi Ueki Ryota Tamate Aya Mizutani Akimoto Ryo Yoshida 《Angewandte Chemie (International ed. in English)》2020,59(10):3871-3875
Various biological behaviors are fueled by “respiration”, which is an example of catabolism. So far, we have reported various self‐oscillating soft materials exhibiting bioinspired dynamic movements. These autonomous polymer systems are driven by the Belousov–Zhabotinsky (BZ) reaction, which is analogous to the tricarboxylic acid (TCA) cycle that is an integral part of respiration. However, in the BZ reaction, the external addition of an oxidizing agent is necessary to initiate the oxidation process, which is realized by intracellular moieties such as ubiquinone in living systems. Herein, we realized self‐oscillating micelles that are driven without the external addition of an oxidizing agent. This was achieved by embedding the oxidizing source into the structure of the self‐oscillating AB diblock copolymers. This strategy introduces a new function equivalent to intracellular oxidizing moieties, and is useful for the design of completely autonomous bioinspired materials. 相似文献
104.
《Particuology》2022
As an innovative thermal energy technology, the spray-type packed bed has advantages of high efficiency and low cost. A liquid distributor is the key component for the spray-type packed bed for scattering heat-transfer liquid drops evenly. In this study, the distribution performance and pressure drop of the perforated plate distributors of different orifice diameters were studied experimentally. The experimental results indicate that orifice diameter has a greater effect on the distribution performance compared to flow rate. With an increase in flow rate, the flow pattern through the distributor changes from the uncovered drop to the covered drop and then to the jet flow. The covered drop pattern shows the best performance with a good distribution and a small pressure drop simultaneously, which is the design and optimization principle of the distributor for a spray-type packed bed. 相似文献
105.
F. Thibault K.A. Grabow C.I. Marcus L.A. Robertson M.C. Stoffel 《Journal of Molecular Spectroscopy》2009,256(1):17-2081
Theoretical and experimental values have been determined for the pressure broadening of the ν1 + ν3 band of acetylene by hydrogen and deuterium at 195 K, and experimental values of the pressure shifts have been determined. Theoretical values have been calculated on the basis of a recent potential energy surface using the close coupling scheme. We discuss the detailed contribution of the various rotational angular momenta of the perturbing gas and the ortho and para contribution to the total pressure broadening cross-sections. We give routes to circumvent the computational cost of such calculations. Experimental values have been measured using a tunable diode laser spectrometer assuming a Voigt line shape. These pressure broadening parameters are compared with measurements performed recently at room temperature and with present measurements performed at 195 K in the ν1 + ν3 band of acetylene. A satisfactory agreement is obtained with the present results and available ones at 295 K. 相似文献
106.
Datian Niu Xuegang Yuan Changjun Cheng Jiusheng Ren 《Acta Mechanica Solida Sinica》2010,23(5):420-427
In this paper, the dynamic characteristics are examined for a cylindrical membrane composed of a transversely isotropic incompressible hyperelastic material under an applied uniform radial constant pressure at its inner surface. A second-order nonlinear ordinary differential equation that approximately describes the radial oscillation of the inner surface of the membrane with respect to time is obtained. Some interesting conclusions are proposed for different materials, such as the neo-Hookean material, the Mooney-Rivlin material and the Rivlin-Saunders material. Firstly, the bifurcation conditions depending on the material parameters and the pressure loads are determined. Secondly, the conditions of periodic motion are presented in detail for membranes composed of different materials. Meanwhile, numerical simulations are also provided. 相似文献
107.
Ocean internal waves interpreted as oscillation travelling waves in consideration of ocean dissipation 下载免费PDF全文
Most studies of the synthetic aperture radar remote sensing of ocean internal waves are based on the solitary wave solutions of the Korteweg-de Vries (KdV) equation, and the dissipative term in the KdV equation is not taken into account. However, the dissipative term is very important, both in the synthetic aperture radar images and in ocean models. In this paper, the traveling-wave structure to characterize the ocean internal wave phenomenon is modeled, the results of numerical experiments are advanced, and a theoretical hypothesis of the traveling wave to retrieve the ocean internal wave parameters in the synthetic aperture radar images is introduced. 相似文献
108.
Jacek Tabor 《Journal of Differential Equations》2002,180(1):171-197
109.
110.
孙元功 《纯粹数学与应用数学》2002,18(2):170-173
对于一类特殊的具有时滞的二阶次线性强迫微分方程x"(t) +a (t)|x(τ(t))|γsgnx(τ(t)) =g(t)(0<τ<1),给出了它的所有解振动的一个充要条件. 相似文献