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1.
利用Laguerre超群K上的广义次拉普拉斯算子L定义K上的Riesz位势,并证明它是Lp(1p+∞)有界和弱(1,1)有界的,即证明K上的Hardy-Littlewood-Sobolev不等式.它为进一步分析K上的偏微分方程问题提供了一个有利的工具. 相似文献
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介绍了清洁生产技术在电厂的应用情况、实施效果。首先概述了清洁生产的概念与重要性;其次对华能北京热电厂减排、节水、节电方面所采取的技术措施进行了详细的分析,经过数据比较,各项指标均达到预期目标;最后,对电厂开展清洁生产工作的发展方向作了一个简单的预测与探讨。 相似文献
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本文中应用Credence公司的Gemini500测试系统对某一SoC芯片内嵌模数转换器进行了测试。根据芯片功能分析和封装形式,对测试板进行了优化设计。根据内嵌式ADC的时序特点进行了测试向量的设计。 相似文献
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根据产品柔性需求和数量柔性需求的程度高低界定了稳定性、产品柔性、数量柔性以及产品数量柔性四类不同的需求环境。通过理论以及案例研究发现,稳定性需求、数量柔性需求、产品柔性需求、产品数量柔性需求分别与效率型、数量反应型、创新反应型和定制反应型供应链存在最佳匹配关系。从市场需求、产品种类变动、利润率、顾客驱动因素、市场资格因素、市场制胜因素等方面归纳了四类供应链的不同特点。研究结果为企业根据需求环境设计供应链提供了决策依据。 相似文献
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Zhen Liu;Qiang Ren;Lifeng Zhang; 《国际钢铁研究》2024,95(9):2400144
Two types of inclusions in the stainless steels are detected: MnO·Cr2O3–MnS dual-phase ones and pure MnS ones. The increase of sulfur content can inhibit the formation of MnO–Cr2O3–MnS inclusions and reduce the harm of MnO·Cr2O3–MnS inclusions on the pitting corrosion of stainless steels. When the sulfur content increases from 26 to 70 ppm, the average pitting potential increases from 0.34 to 0.4 VSCE due to the decrease in the number density of MnO–Cr2O3–MnS inclusions. A Cr-depletion zone exists in the steel matrix around MnO–Cr2O3–MnS inclusions. The size of pits induced by MnO·Cr2O3–MnS inclusions is larger, which poses a more serious threat to the pitting resistance of stainless steels. 相似文献
9.
《Materials Chemistry and Physics》1986,14(1):25-40
The kinetics of etching of doubly rotated quartz plates are studied. The Arrhenius plots are found to be linear and values of the apparent activation energy in the range 0.35–0.42 eV are evaluated in accordance with values previously published for singly rotated quartz plates. The evolution of the surface texture of SC and RT quartz plates during the etching with ammonium bifluoride is investigated. The roughness parameters decrease rapidly with increasing depth of etch. This large and rapid decrease seems to correspond to the development of etch patterns all uniformly oriented on the plane surface of resonators. The profilometry traces show directional effects attributed to asymmetrical etch rate distributions which are also typified by the SEM micrographs. Furthermore the distinctive dissolution figures formed on the two sides of RT and SC quartz resonators are characteristic to the crystal orientation which seems to govern the dissolution process. 相似文献
10.
《Water research》1996,30(10):2413-2423
Transport and deposition of colloidal Fe, Mn and Al oxides play key roles in the cycling of toxic transition metals in aquatic environments because these colloids strongly bind transition metals. Further, attachment of biological cells and biofilm growth on surfaces can indirectly affect toxic metal distribution by influencing the deposition of colloidal oxides to surfaces. To elucidate the mechanisms governing these processes, deposition of colloidal oxides onto surfaces must be evaluated in the presence of suspended and adherent bacterial cells. Both particle size and concentration are expected to influence deposition. An experimental protocol was developed to determine the size distribution of iron colloids in mixtures with suspended cells. A Ti(III) reagent was used to reduce and dissolve colloidal Fe(III) from mixtures containing both suspended cells and Fe colloids. The size distribution of Fe(III) colloids in the original solution was then determined from the difference between size distributions before and after dissolution of Fe with Ti(III). The Ti(III) reagent dissolved over 95% of the Fe colloids without altering the size distribution of suspended bacterial cells, and the method accurately determined the size distribution of Fe colloids added to cell suspensions. The applicability of this protocol was tested by applying it to a study of the deposition of Fe(III) oxide particles onto glass surfaces with and without biofilms of the bacterium Burkholdaria cepacia 17616. Experimental results using a laboratory biofilm reactor indicated that the deposition rate of Fe(III) colloids was not significantly affected by the presence of B. cepacia biofilms or by the presence of previously deposited Fe. However, deposition of Fe to reactor surfaces other than the glass surfaces may have interfered with the analyses, and atomic absorption measurements showed a slight increase in Fe deposition onto glass surfaces with biofilms present. Fe deposition to the composite of all reactor surfaces increased with increasing colloidal particle size, indicating a dominance of interception and/or sedimentation in controlling Fe deposition on surfaces in the biofilm reactor. 相似文献