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81.
Tang Y.B. Chen Y.G. Teng B.H. Fu H. Li H.X. Tu M.J. 《IEEE transactions on magnetics》2004,40(3):1597-1600
We calculate the magnetic field distribution of a permanent magnetic circuit with an air gap in a magnetic refrigerator by a finite-element method, and compare the field strengths of different structural parameters of the magnetic circuit. We show how the structure of the magnetic circuit can be optimized and present some approaches to improve the structure for a specific magnetic circuit. The main purpose is to provide basic parameters for the design of a practical magnetic refrigerator. 相似文献
82.
Tianxi Sun Zhiguo Liu Yude Li Guangpu Wang Guanghua Zhu Qing Xu Xiaoyan Lin Hui Liu Ping Luo Qiuli Pan Yuepeng Teng Xunliang Ding 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(24):3554-3560
A laboratory micro X-ray fluorescence spectrometer based on a special polycapillary X-ray lens (PXRL) was used to carry out the source apportionment of aerosol particles. In the curve of the distribution of the X-ray intensity in the focal spot of the special PXRL, there was a plateau with a diameter of 21.3 μm in which the distribution of the X-ray intensity was homogeneous. The gain in flux density in the plateau of the PXRL is 1490. The uniformity of this plateau was 2.9%. This was helpful for the quantitative X-ray fluorescence analysis of a single aerosol particle with smaller size than that of the plateau of the PXRL. The fingerprint database of aerosol particles with given sizes from various air pollution sources was established with the single particle analysis method. The size-resolved source apportionment of aerosol particles in haze in Beijing city was performed with this fingerprint database. 相似文献
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Jintuo Zhu Xinjian He Liang Wang Xiaoxue Liao Guangping Teng Pengli Jing 《矿业科学技术学报(英文版)》2022,32(1):215-224
High humidity and high dust concentration in deep coal mines may severely challenge the performance of respirators worn by coal miners.This paper aims at quantitatively evaluating the respirators used in deep coal mines and providing scientific guidance for the respiratory protection of miners.Based on the self-designed in-situ PM2.5collector,controllable PM2.5generator,human breathing simulator,and respirator simulation testing system,under the simulated deep mine working ... 相似文献
87.
Dingfang Liu Zheng Teng John J. Sansalone Frank K. Cartledge 《Canadian Metallurgical Quarterly》2001,127(10):879-888
Most current control strategies for storm water treatment utilize fixed or filter-bed media with specific gravity (ρs) greater than 1.0. In contrast to Part I, Part II focuses on such higher density (ρs > 1.0) manganese-oxide-coated media that can be used in combined unit operations and processes for in-situ treatment of storm water. Methods were developed to coat manganese oxides onto sand and cementitious media for storm water treatment. With respect to manganese, coatings of ramsdellite produced a point of zero charge (PZC) of 5.2, while mixtures of birnessite and cryptomelane produced a PZC of 2.6 Manganese oxide increased the specific surface area (SSA) of sand and cementitious media. Manganese-oxide-coated sand (MOCS) produced a larger SSA (2.48-m2∕g), as compared with birnessite-coated media (BCM) (1.51 m2∕g), while the two have a similar surface charge (PZC = 6.4). Manganese-oxide-coated cementitious media (MOCM) produced a significantly larger SSA (19.49 m2∕g), as compared with coated sand, and SEM analyses indicated the surface contained manganese oxide and calcite of thickness 10–30 μm. Based on the results, coated cementitious media provided surface characteristics that can significantly enhance filtration and adsorption of heavy metal in storm water, in comparison to sand. 相似文献
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马腾 《Canadian Metallurgical Quarterly》2011,10(2)
儒法思想之融通,在历史渊源上呈现为"儒法同宗"的命题.管仲的思想是其实质依据,后来稷下学官的<管子>将其文本化.李悝、吴起师儒而任法,开"儒家"向"法家"转变之先河."杂家"尸佼曾为商鞅之师,其思想以儒家思想为主体,杂以法家思想,亦体现了儒法思想的融通."转关人物"的思想不但从学术源流上印证了法家出于儒家的命题,且揭示了法家的"政治家"本质,蕴涵了对传统政治法律文化中人物思想矛盾性的解释. 相似文献
90.
一种新的图像不变特征研究 总被引:2,自引:0,他引:2
为了解决图像特征受灰度及几何畸变的影响,本文利用物理学相关概念对图像进行描述,定义了图像的质量,重心,转动惯量,提出了一种新的图像不变特征即归一化转动惯量(NMI)特征,对其不变性进行了分析,实验结果表明,图像的归一化转动惯量特征具有抗灰度及TRS不变性,且提取方法简单,易于实现。 相似文献