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单通道和多通道毛细管光学元件-技术发展水平和应用(英文)

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光学精密工程 2007年第12期15卷 1932-1945页

作者： A Bjeoumikhov r Wedell S Bjeoumikhova IfG Institute for Scientific Instruments GmbH 12489 BerlinRudowerChaussee 29/31Germany Institut für angewandte Photonik e.V. 12489 BerlinRudowerChaussee 29/31Germany Bundesanstalt für Materialforschung und-prüfung 12200 BerlinGermany

毛细管光学元件在X射线分析中的应用已有20多年的历史,在这段时间里,毛细管光学元件的制作技术发生了很大的变化。上世纪90年代初,使用的是组装的毛细管光学元件,目前,集成的多通道毛细管光学元件已广泛地应用于市场销售的X射线分析设... 详细信息

毛细管光学元件在X射线分析中的应用已有20多年的历史,在这段时间里,毛细管光学元件的制作技术发生了很大的变化。上世纪90年代初,使用的是组装的毛细管光学元件,目前,集成的多通道毛细管光学元件已广泛地应用于市场销售的X射线分析设备中。这些元件的毛细管直径在微米量级,其光学性质可以根据几何光学的光线追迹计算进行描述。最近,由于多通道毛细管制作技术的改进,已成功制成了200 nm及以下通道尺寸的毛细管光学元件。在这样小的通道尺寸下,观察到了X射线辐射的波动效应。最后文章介绍了毛细管光学元件在X射线微荧光分析和微衍射方面的应用。

关键词： X射线毛细管光学元件波动特性纳米毛细管 X射线分析

STUDY　OF　INTErACTION　BETWEEN　VOrTICES　AND　A　FrEE　SUrFACE　PArT　Ⅱ：INTErACTION　OF　DOUBLE　VISCOUS　VOrTEX　DIPOLES　WITH　A　FrEE　SUrFACE

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Journal of Hydrodynamics 1995年第1期7卷 17-32页

作者： Wu Chui-jie Tan Bo-yan (Air Force Institute of Meteorology,Nanjing 211101 P. r. China)Ma Hui-yang(Graduate School of Academia Sinica, Beijing 100039 P. r. China)( Air Force Inst of Meteorology Nanjing China

In this paper the VOF (Volume of Fluid) method is used to numerically study the interaction of double viscous vortex dipoles with free surface in a two dimensional incompressible flow field. From the results of this research, it is found that the general consequence of the interaction is qualitatively equivalent to the problem of a single vortex dipole interacts with a free surface.

关键词： vortex motion free surface computational fluid mechanics.

Electron states and electron raman scattering in semiconductor double cylindrical quantum well wire

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Chinese Physics B 2016年第11期25卷 453-460页

作者： M Munguía-rodríguez ri Betancourt-riera re Betancourt-riera r riera J M Nieto Jalil Departamento de Investigación en Física Universidad de Sonora Apartado Postal 5-88 83190 Hermosillo Sonora México Instituto Tecnológico de Hermosillo. Avenida Tecnologico S/N Col. Sahuaro 83170 Hermosillo Sonora México Tecnológico de Monterrey-Campus Sonora Norte. Bulevar Enrique Mazón Lopez No. 965 83000 Hermosillo Sonora México

The differential cross section for an electron raman scattering process in a semiconductor GaAs/AlGaAs double quantum well wire is calculated,and expressions for the electronic states are *** system is modeled by considering T = 0 K and also with a single parabolic conduction band,which is split into a subband system due to the *** gain and differential cross-section for an electron raman scattering process are *** addition,the emission spectra for several scattering configurations are discussed,and interpretations of the singularities found in the spectra are *** electron raman scattering studied here can be used to provide direct information about the efficiency of the lasers.

关键词： Electron cylindrical confinement conduction radius decoupling AlGaAs parabolic modeled resonant

Biodegradation and ecotoxicological assessment of pectin production wastewater

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Journal of Environmental Sciences 2009年第11期21卷 1613-1619页

作者： V.reginatto E.r.Amante K.Gerhardy S.Kunst N.Duran Department of Food Science and Technology Federal University of Santa Catarina - Rodovia Admar Gonzaga Institute of Water Quality-University of Hannover Biological Chemistry Laboratory Chemistry Institute State University of Campinas-UNICAMP

The chemical composition of pectin production wastewater and its toxicity during biological treatment were investigated. Samples of wastewater from different steps of a pectin production wastewater biological treatment plant were investigated including the influent of the treatment （1）, after denitrification tank （2）, after anaerobic treatment （3） and final effuent （4）. The conventional physicochemical characteristics of samples did not indicate wastewater toxicity. However, toxicity assessments carried out on Vibrio fischeri and Scenedesmus subspicatus indicated low EC50 values. The fractionation of the samples using an XAD resin showed that the toxicity was associated with the organic matter. Wastewater apparent molecular mass distributions were 14.3, 25.0, 24.4 and 29.6 kDa for samples 1-4, respectively. Finally, characteristics of the sample by pyrolisis-gas chromatography-mass spectrometry （Py-CG-MS） demonstrated its polyphenolic nature and a 23% increase in the levels of such compounds after the first biological treatment step.

关键词： pectin wastewater bioassays ecotoxicity pyrolisis-gas chromatography-mass spectrometry

Effects of rare Earth Elements on the Characteristics of Low Temperature Plasma Nitrocarburized Martensitic Stainless Steel

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Journal of Materials Science & Technology 2012年第11期28卷 1046-1052页

作者： r.L.Lju Y.J.Qiao M.F.Yan Y.D.Fu College of Materials Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Low temperature plasma nitrocarburizing of 17-4PH martensitic stainless steel was conducted at 430 ℃ with and without rare earth （rE） addition. The microstructure, kinetics, microhardness, wear behavior as well as corrosion resistance of the modified layer were studied by optical microscopy, X-ray diffraction, Vickers microhardness tester, pin-on-disc tribometer and potentiodynamic polarization tests. The results show that the thickness of plasma rE nitrocarburized layer is much thicker than that formed by nitrocarburizing without rE addition. The incorporation of rE does not change the kind of the phases and the nitrocarburized layer consists mainly of nitrogen and carbon expanded martensite （aN）, γ-Fe4N and a-Fe with a trace of CrN phases. The surface microhardness of plasma nitrocarburized layer can be increased by 100 HV after rE addition. Wear resistance of the specimen can be apparently improved by low temperature plasma nitrocarburizing with and without rE addition and without sacrificing its corrosion resistance. Wear reduction effect of low temperature plasma nitrocarburizing with rE addition is better than that of the conventional one.

关键词： Stainless steel Low temperature Plasma nitrocarburizing rare earth (rE) Wear and friction

User-friendly finite element design of main entries, barrier pillars,and bleeder entries

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International Journal of Mining Science and Technology 2018年第1期28卷 3-10页

作者： William G.Pariseau Mark K.Larson Heather E.Lawson Douglas r.Tesarik Department of Mining Engineering University of Utah Spokane Mining research Division NIOSH

This contribution describes development and application of a user-friendly finite element program,UT3PC, to address three important problems in underground coal mine design:(1) safety of main entries,(2) barrier pillar size needed for entry protection, and(3) safety of bleeder entries during the advance of an adjacent longwall *** the finite element method is by far the most popular engineering design tool of the digital age, widespread use by the mining community has been impeded by the relatively high cost of and the need for lengthy specialized training in numerical *** of UT3PC overcomes these impediments in three easy ***, a material properties file is prepared for the considered ***, mesh generation is automatic through an interactive process.A third and last step is simply execution of the *** using data from several western coal mines illustrate the ease of using the application for analysis of main entries, barrier pillars, and bleeder entry safety.

关键词： Finite element Coal Mine layout design Main entries Barrier pillars Bleeder entries

Uniformity of TiN Films Fabricated by Hollow Cathode Discharge

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Plasma Science and Technology 2010年第2期12卷 212-217页

作者：姜海富巩春志田修波杨士勤 r.K.Y.FU P.K.CHU State Key Lab.of Advanced Welding Production & Technology School of Material Science and Engineering Harbin Institute of Technology Department of Physics and Materials Science City University of Hong Kong

Titanium nitride （TIN） films were deposited on AISI 304 stainless steel substrates using hollow cathode plasma physical vapor deposition （HC-PVD）. Titanium was introduced by eroding the Ti cathode nozzle and TiN was formed in the presence of a nitrogen plasma excited by radio frequency （rF）. The substrate bias voltage was varied from 0 to -300 V and the uniformity in film thickness, surface roughness, crystal size, microhardness and wear resistance for the film with a diameter of 20 mm was evaluated. Although the central zone of the plasma had the highest ion density, the film thickness did not vary appreciably across the sample. The results from atomic force microscopy （AFM） revealed a low surface roughness dominated by an island-like morphology with a similar crystal size on the entire surface. Higher microhardness was measured at the central zone of the sample. The sample treated at -200 V had excellent tribological properties and uniformity.

关键词： hollow cathode TiN film uniformity

Hydrodynamics and Sensitivity Analysis of a Williamson Fluid in Porous-Walled Wavy Channel

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Computers, Materials & Continua 2021年第9期68卷 3877-3893页

作者： A.Shahzad W.A.Khan r.Gul B.Dayyan M.Zubair Department of Mathematics COMSATS University IslamabadAbbottabad Campus22060Pakistan Department of Mechanical Engineering College of Engineering Prince Mohammad Bin Fahd UniversityAl Khobar31952Kingdom of Saudi Arabia

In this work,a steady,incompressible Williamson fluid model is investigated in a porous wavy *** situation arises in the reabsorption of useful substances from the glomerular filtrate in the *** 80%reabsorption,urine is left,which behaves like a thinning *** laws of conservation of mass and momentum are used to model the physical *** analytical solution of the problem in terms of stream function is obtained by a regular perturbation expansion *** asymptotic integration method for small wave amplitudes and the rK-Fehlberg method for pressure distribution has been used inside the *** is demonstrated that the forward flow becomes fast in the narrow region(at x=0.75),which dominates the upward flow inside the *** study the impact of model parameters on outputs,we applied normalized local sensitivity analysis and noticed that the most influential parameter for the longitudinal velocity profile is the dimensionless wave *** reabsorption parameter is sensitive for transverse velocity in the narrow region,and the Weissenberg number has a strong effect on the pressure inside the ***,the least sensitive parameters for the velocity components and pressure have been identified.

关键词： Sensitivity analysis Williamson fluid regular perturbation method asymptotic approximation rK-Fehlberg method kidney flow

Phase transformation and crystal growth behavior of 8mol%(SmO1.5, GdO1.5, and YO1.5) stabilized ZrO2 powders

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International Journal of Minerals,Metallurgy and Materials 2017年第7期24卷 842-849页

作者： r.Mahendran S.P.Kumaresh Babu S.Natarajan S.Manivannan A.Vallimanalan Department of Metallurgical and Materials Engineering National Institute of Technology Tirchirappalli 620015 Tamil Nadu india

Nanocrystalline powders of ZrO_2–8mol%SmO1.5（8Sm SZ）, ZrO_2–8mol%GdO1.5（8Gd SZ）, and ZrO_2–8mol%YO1.5（8YSZ） were prepared by a simple reverse-coprecipitation technique. Differential thermal analysis/thermogravimetry（DTA/TG）, Fourier transform infrared spectroscopy（FTIr）, X-ray diffraction（XrD）, raman spectroscopy, and high-resolution transmission electron microscopy（HrTEM） were used to study the phase transformation and crystal growth behavior. The DTA results showed that the ZrO_2 freeze-dried precipitates crystallized at 529, 465, and 467°C in the case of 8Sm SZ, 8Gd SZ, and 8YSZ, respectively. The XrD and raman results confirmed the presence of tetragonal ZrO_2 when the dried precipitates were calcined in the temperature range from 600 to 1000°C for 2 h. The crystallite size increased with increasing calcination temperature. The activation energies were calculated as 12.39, 12.45, and 16.59 k J/mol for 8Sm SZ, 8Gd SZ, and 8YSZ respectively.

关键词： zirconia thermal analysis reverse coprecipitation activation energy