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道德哲学对道德教育的贡献

上海教育科研 1993年第1期 27-30,26页

作者： Chazan B.I Soltis j.f. 戚万学南京师范大学教育系

当代道德教育的最显著特征就是说做不一。尽管对教育目的的大量正式陈述都断言,通过公共教育培养在道德上负责的公民乃是教育的核心,但事实上,能够认真、系统地对待道德教育的学校並不多;尽管那些市民、政治和教育领袖们口口声声说,教... 详细信息

当代道德教育的最显著特征就是说做不一。尽管对教育目的的大量正式陈述都断言,通过公共教育培养在道德上负责的公民乃是教育的核心,但事实上,能够认真、系统地对待道德教育的学校並不多;尽管那些市民、政治和教育领袖们口口声声说,教育在传递当今世界复杂的生活所必需的“道德和精神价值”方面起重要作用,但是为这种价值教育作出正式规定的教育体制也还毕竟是少数;人们常说教师乃是专少年品格形成的重要力量,然而,经过旨在提高道德教育工作者效能的训练的教师实为数寥寥。总之,在官方语言和当代实际的道德教育实践之间存在一种令人不安的不一致。即使我们不否认那些讲“官话”的人的诚意。

关键词：道德教育价值教育教育工作者道德哲学教育目的公共教育道德行为官方语言道德领域道德原则

CORROSION PROTECTION Of Al CATHODES IN ZINC ELECTROLYSIS

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Acta Metallurgica Sinica(English Letters) 1999年第3期12卷 221-228页

作者： Lu, f. Van Ooij, W.j. Beijing Inst of Aeronautical Materials Beijing China

A new pretreatment or a coating for Al was developed and tested to protect the Al effectively from corrosion when it was connected to pure zinc at electroplating potential and exposed to an acidic sulfate solution. It was found out that (1) Al alloy purity and electroplating potential have a large effect on galvanic corrosion between Zn-Al couples; (2) BTSE silane pretreatment and polyurethane coating have better performance in corrosion protection, which are evaluated by EIS, salt spray test and immersion test for Al cathodes in Zinc electrolyte; (3) BTSE treatment or BTSE plus polyurethane coating has the best anti-corrosion performance and can protect the Al cathode effectively in zinc electrolysis.

关键词： Aluminum Electrolysis

Metasomatic Stages and Scapolitization Effects on Chemical Composition of Pasveh Pluton,NW Iran

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journal of Earth Science 2011年第5期22卷 619-631页

作者： S A Mazhari S Amini j Ghalamghash f Bea Department of Geology Payame Noor University Department of Geology Tarbiat Moallem University Geological Survey of Iran Department of Mineralogy and Petrology Fuentenueva CampusUniversity of Granada

Pasveh gabbros are mafic component of a plutonic complex in the northwest Sanandaj- Sirjan Zone. These cumulative rocks are composed of plagioclase and calcic clinopyroxene （Cpx）, which yield unusually high CaO （〉19 wt.%） in whole-rock chemistry. Petrographical and geochemical data suggest that Pasveh gabbros can be divided into two groups： free scapolite and scapolite-bearing gabbros. The second group has higher Na20, K20, and P205 relative to free scapolite ones and is enriched in LIL （large ion lithophile） and HfS （high field strength） elements. Two stages of metasomatism affected the primary composition of mafic rocks. firstly, high temperature reaction caused to invert primary high Ti clinopyroxene to low Ti cUnopyroxene＋high Ti amphibole. This reaction was extensive and included all gabbroic samples. Hydrothermal fluids involved in this process can be derived from dehydration reactions of country rocks or from other magmas incorporated in the formation of Pasveh complex pluton. The second metasomatic stage relates to scapolitization of limited parts of gabbroic rocks. An external saline fluid, which is composed of major NaCI and minor KCI and P205 components, impacted locally on Pasveh gabbros and formed the second metasomatic stage. Possible sources of Na and Cl are primary evaporites or brines, which were present in the host sediments of the gabbros. The carbonate-free nature of these hydrothermal fluids suggests that hydrothermal fluids responsible for the formation of scapolite in Pasveh gabbros are derived from marine evaporitic parentage.

关键词： Iran Sanandaj-Sirjan Zone Pasveh pluton gabbro metasomatism high Ti Cpx low Ti Cpx amphibole scapolite.

HEAT TRANSfER BEHAVIOR Of SUPERALLOY DROPLETS DURING SPRAY fORMING

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Acta Metallurgica Sinica(English Letters) 2000年第2期13卷 800-805页

作者： j.f. Sun, j. Shen, Z. Y. Li, j. jia and Q.C. Li National Key Laboratory of Metal Precision Hot Processing, Harbin Institute of Technology, Harbin 150001, China

Based on the Newtonian heat transfer formulation and classical heterogeneous nucleation theory, a mathematical model has been established to predict the profile of flight velocity, heat transfer coefficient, temperature, solid fraction and cooling rate of atomizing droplets for a superalloy. The results indicated that above parameters change with different droplet size and flight distance. The changing trend as well as the mechanism for the change are described and discussed.

关键词： spray forming superalloy heat transfer mathematical model

Carbon isotopes of graphite:Implications on fluid history

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Geoscience frontiers 2012年第2期3卷 197-207页

作者： f.j.Luque E.Crespo-feo j.f.Barrenechea L.Ortega Departamento de Cristalografía y Mineralogía facultad de Geología Universidad Complutense de Madrid 28040 MadridSpain Instituto de Geociencias(UCM-CSIC) Jos Antonio Novais 228040 MadridSpain Departamento de Cristalografia y Mineralogia facultad de Geología Universidad Complutense de Madrid28040 MadridSpain Departamento de Cristalografía y Mineralogía facultad de Geología Universidad Complutense de Madrid28040 MadridSpain

Stable carbon isotope geochemistry provides important information for the recognition of funda- mental isotope exchange processes related to the movement of carbon in the lithosphere and permits the elab- oration of models for the global carbon cycle. Carbon isotope ratios in fluid-deposited graphite are powerful tools for unravelling the ultimate origin of carbon （organic matter, mantle, or carbonates） and help to constrain the fluid history and the mechanisms involved in graphite deposition. Graphite precipitation in fluid-deposited occurrences results from C02- and/or CH4-bearing aqueous fluids. fluid flow can be considered as both a closed （without replenishment of the fluid） or an open system （with renewal of the fluid by successive fluid batches）. In closed systems, carbon isotope systematics in graphite is mainly governed by Rayleigh precipi- tation and/or by changes in temperature affecting the fractionation factor between fluid and graphite. Such processes result in zoned graphite crystals or in successive graphite generations showing, in both cases, isotopic variation towards progressive 13C or 12C enrichment （depending upon the dominant carbon phase in the fluid, C02 or CH4, respectively）. In open systems, in which carbon is episodically introduced along the fracture systems, the carbon systematics is more complex and individual graphite crystals may display oscillatory zoning because of Rayleigh precipitation or heterogeneous variations of 613C values when mixing of fluids or changes in the composition of the fluids are the mechanisms responsible for graphite precipitation.

关键词： Graphite Carbon isotopes Crust C-O-H fluids

Drivability of Large Diameter Steel Cylinders During Hammer-Group Vibratory Installation for the Hong Kong–Zhuhai–Macao Bridge

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Engineering 2023年第1期20卷 180-191页

作者： W.j.Lu B.Li j.f.Hou X.W.Xu H.f.Zou L.M.Zhang Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyKowloonHong Kong 999077China The Hong Kong University of Science and Technology Shenzhen Research Institute Shenzhen 518057China Tianjin Port Engineering Institute Co. Ltd.of CCCC First Harbor Engineering Co.Ltd.Tianjin 300222China Key Laboratory of Port Geotechnical Engineering Ministry of Communications of People’s Republic of ChinaTianjin 300222China CCCC first Harbor Engineering Company Ltd. Tianjin 300461China AECOM Asia Company Limited Hong Kong 999077China

The Hong Kong–Zhuhai–Macao Bridge(HZMB)involved the installation of 120 mega-cylinders with a diameter of 22 m,weights up to 513 t,and penetration depths up to 33 m using an eight-vibratory hammer *** to the lack of engineering experience on the drivability of large-diameter cylinders under multiple vibratory hammers,predicting the penetration rate and time of steel cylinders is an open challenge that has a considerable impact on the construction control of the *** this study,the vibratory penetration of large-diameter steel cylinders in the HZMB is investigated based on geological surveys,field monitoring,and drivability *** vibratory penetration rate,installation accuracy,and dynamic responses of the steel cylinders at both the eastern and western artificial islands are *** dynamic soil resistance has a great influence on the cylinder ***,the current design methods for estimating the vibratory driving soil resistance are proven inaccurate without considering the scale ***,a modified method with a normalized effective area ratio A_(r,eff)is proposed in this study to calculate the vibratory soil resistance for open-ended thin-wall cylinders under unplugged *** the scale effects on the vibratory driving soil resistance,the proposed method leads to closer results to the measured data,providing a reference for future engineering practice.

关键词： Hong Kong-Zhuhai-Macao Bridge Vibratory pile driving Wave equation analysis Large-diameter steel cylinder Artificial island offshore foundati ons

pH-distribution of cerium species in aqueous systems

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journal of Rare Earths 2012年第6期30卷 559-562页

作者： B.Bouchaud j.Balmain *** f.Pedraza University of La Rochelle Laboratory of Engineering Science for the Environment LaSIE FRE-CNRS3474Avenue Michel Crépeau 17042 La Rochelle cedex 01FRANCE

Cerium-based oxide coatings can be obtained through either chemical or electrochemical processes on various conductor and semiconductor substrates. In both cases the films develop through a precipitation mechanism, which strongly depends on the solution chemistry. In the particular case of the electrolytic approach, the elaboration parameters play a key role on the interfacial pH modification thereby leading to an indirect precipitation mechanism. Indeed, the nucleation and growth mechanisms of crystallites and the composition of the resulting layers have been shown to be also strongly affected by the deposition conditions as well as by the substrate composition, which could in turn modify the protectiveness provided by such coatings. Therefore a better fundamental understanding of the system is required, in particular of the distribution of cerium-containing species in aqueous solution. To this end, the present work intended to develop a diagram showing the distribution as well as the relative amount of Ce（Ⅲ）/Ce（Ⅳ） species in aqueous media as a fimction of the pH range. The resulting pH-distribution diagram turned out to be a useful tool to predict the relevant precipitation mechanisms and species involved during the growth of ceriuna-containing films and to draw correlations with the characteristics of the as-deposited films.

关键词： pH-distribution diagram electrodeposition cerium-based oxide films precipitation mechanisms rare earths

3D flow Past Transonic Turbine Cascade SE 1050-Experiment and Numerical Simulations

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journal of Thermal Science 2013年第4期22卷 311-319页

作者： D.imurda j.f.rst M.Luxa Institute of Thermomechanics AS CR v.v.i.Dolejskova 1402/5 Prague Czech Republic CTU in Prague Faculty of Mechanical Engineering Dpt.of Technical MathematicsKarlovo Náměstí 13 Prague Czech Republic

This paper is concerned with experimental and numerical research on 3D flow past prismatic turbine cascade SE1050 （known in QNET network as open test case SE1050）. The primary goal was to assess the influence of the inlet velocity profile on the flow structures in the interblade channel and on the flow field parameters at the cascade exit and to compare these findings to results of numerical simulations. Investigations of 3D flow past the cascade with non-uniform inlet velocity profile were carried out both experimentally and numerically at subsonic （M2 = 0.8） and at transonic （M2 = 1.2） regime at design angle of incidence. Experimental data was obtained using a traversing device with a five-hole conical probe. Numerically, the 3D flow was simulated by open source code OpenfOAM and in-house code. Analyses of experimental data and CfD simulations have revealed the development of distinctive vortex structures resulting from non-uniform inlet velocity profile. Origin of these structures results in increased loss of kinetic energy and spanwise shift of kinetic energy loss coefficient distribution. Differences found between the subsonic and the transonic case confirm earlier findings available in the literature. Results of CfD and experiments agree reasonably well.

关键词： blade cascade vortex structures transonic flow CfD

Unsteady magnetohydrodynamic stagnation point flow — closed-form analytical solutions

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Applied Mathematics and Mechanics(English Edition) 2019年第4期40卷 449-464页

作者： T.G.fANG f.j.WANG Bo GAO Mechanical and Aerospace Engineering Department North Carolina State University School of Energy & Power Engineering Jiangsu University

This paper investigates the unsteady stagnation point flow and heat transfer of magnetohydrodynamic(MHD) fluids over a moving permeable flat surface. The unsteady Navier-Stokes(NS) equations are transformed into a similarity nonlinear ordinary differential equation, and a closed form solution is obtained for the unsteadiness parameter of 2. The boundary layer energy equation is transformed into a similarity equation,and is solved for a constant wall temperature and a time-dependent uniform wall heat flux case. The solution domain, velocity, and temperature profiles are calculated for different combinations of parameters including the Prandtl number, mass transfer parameter, wall moving parameter, and magnetic parameter. Two solution branches are obtained for certain combinations of the controlling parameters, and a stability analysis demonstrates that the lower solution branch is not stable. The present solutions provide an exact solution to the entire unsteady MHD NS equations, which can be used for validating the numerical code of computational fluid dynamics.

关键词： unsteady stagnation point flow stretching/shrinking sheet magnetohy-drodynamic(MHD) Navier-Stokes(NS)equation