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根据办《自然杂志》的体会,探索高级科普期刊的办刊之道。以一流科学家为作者主体,采用约稿和编委推荐制为主要组稿方式是确保期刊学术质量的根本;聘请各学科高级专家加入编委会,健全编辑的学科方向,建设好编委会和编辑部是办好期刊的保证;培养读者对科学的兴趣,帮助读者拓宽知识面,提高科学素养是办刊的宗旨;弘扬科学人文精神,打破文理藩篱是办刊的追求。  相似文献   
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1 Introduction Itiswellknownthatmetalhydridesareanidealmediumforhydrogenstorageduetotheirhighdensityandhigh purityofhydrogen .However ,allknownconventionalmetalhydrides ,includingintermetalliccompoundsAB5,AB2 ,andAB ,havereversiblegravi metricH densitiesnomo…  相似文献   
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Zr65Al10Ni10Cu15, Zr52.5Al10Ni10Cu15Be12.5 and Zr52.5Al10Ni14.6 Cu17.9Ti5bulk amorphous alloys were prepared by copper mould casting. The crystallization kinetics was measured by differential scanning calorimeter(DSC) with different heating rates, and the activation energy was calculated using Kissinger equation. The relationship between thermal stability and rate constant of crystallization reaction is discussed on the view of crystallization kinetics, and the effect of small atom Beryllium on thermal stability of bulk amorphous alloys is also studied.  相似文献   
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1 Introduction AB5 typehydrogenstoragealloyshavebeeninten sivelyinvestigatedsincethefirstuseasanelectrodereportedbyJustiin 1973[1] .ThecommercialAB5electrodesusemischmetal,alowcostmixtureofrareearthelements ,asasubstituteforLa ,whiletheB5componentremainsprimar…  相似文献   
5.
Surface morphologies of Zr52.5 Al10 Ni10 Cu15 Be12.5 bulk metallic glass after being rolled at both a temperature around T9 and near ( Tx - 50) K were investigated with a scanning electron microscopy. Macroscopic and microscopic observation results show that squamae, cracks, steps and wedges exist on the surface when the samples were rolled at temperatures around Ty. However, a smooth and fiat surface appears when the samples were rolled at temperatures near ( Tx - 50) K. These results indicate that the mode of deformation in the supercooled liquid region is a partially homogeneous flow at a temperature around T9, and a fully homogeneous one at temperatures near ( Tx - 50) K. According to the results, it is more feasible to roll the amorphous alloys at temperatures near ( Tx - 50) K to obtain parts with smooth and fiat surface.  相似文献   
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Ml0.7Mm0.3Ni3.7Co0.7Mn0.4Al0.2 nanocrystalline hydrogen storage materials are prepared by melt-spinning(MS).X-ray diffraction is used for the measurement of the nanocrystalline size.Compared to the electrode of polycrystalline alloys,the property of activation MH9metal hydride)electrode of the alloys with nanometer scale became worse and the inital discharge capacity decreased.It may be ascribed to the decrease of the total amount of rare earth metals and the increase of oxygen on the surface from the analysis of components of the alloys.After heat-treatment,the electrochemical performance of MH electrode of as-spun alloys could be improved,which could be attributed to the alleviation of the lattice strain.  相似文献   
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以《自然杂志》为例探讨了高级科普期刊在选题策划和组稿时如何打破文理藩篱,融合科学精神和人文精神的方法和途径。高级科普编辑不仅应选择具有人文精神和强烈社会责任感的科学家来撰稿,还应选择有助于引导读者关注人文精神的科学研究内容进行报道。  相似文献   
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1IntroductionSince a non-noble bulk metallic glassy alloy was dis-covered byInoue ,et al.[1]in 1988 , many stable amor-phous alloy systems with higher glass-forming abilityand lower critical cooling rates have been developed .Among them, Zr-based metallic glassy alloys are in-tenselyinvestigated because of their wider supercooledliquid region and other favorable thermodynamic andmechanical properties .In general ,surface morphologyof amorphous alloy parts is veryi mportant forindustri-al and …  相似文献   
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