热压反应合成 TiAl 合金的密度及孔隙分布

采用Ｔｉ,Ａｌ混合元素粉,通过热压反应合成方法,研究了热压温度对Ｔｉ－４８Ａｌ（原子数分数）致密化行为和孔隙分布的影响．结果表明：随着热压温度的升高,制备的材料致密度升高,而在１４００℃下,由于晶粒粗大,导致材料的致密度难以继续提高,冷压坯上密度的不均匀性直接影响热压坯中材料的孔隙分布;提高冷压坯的密度,能在一定程度上使热压坯的密度升高     

Al—12Ti机械合金化过程的结构演变

采用三种不同类型的球磨机对高Ａｌ含量的Ａｌ－Ｔｉ元素进行球磨试验，研究了其结构演变的特点和影响因素．Ａｌ－Ｔｉ混合粉末在高能球磨过程中的结构演变与球磨输入能量有很大关系，输入能量高的球磨方式能导致Ｔｉ完全过饱和固溶于Ａｌ中，甚至形成部分非晶相和Ｌｌ２有序相；中等输入能量只能形成过饱和固溶体，不能形成非晶相；输入能量较低则不能使Ｔｉ完全溶于Ａｌ．球磨输入能量还对最终球磨态粉末的畸变程度和晶粒大小有重要作用，输入能量高的球磨机制备的机械合金化粉末的畸变明显高于另外两种球磨机制备的粉末，且晶粒更细．高的畸变和细的晶粒可能是促进部分非晶化的原因之一．     

Ti对Al2O3／Ni复合材料相界面润湿及力学性能的影响

以无压烧结方式制备了Ａｌ２Ｏ３／２０％Ｎｉ（Ｔｉ）（体积分数）复合材料．通过分析Ｔｉ元素的分布状态，研究了Ｔｉ添加剂对Ａｌ２Ｏ３／２０％Ｎｉ复合材料相界面润湿及力学性能的影响规律．结果表明，Ｔｉ元素集中分布在Ａｌ２Ｏ３／Ｎｉ相界面附近，并通过促进相界面润湿，强化相界面结合而显著改善复合材料的力学性能．实验成分范围内，随Ｔｉ含量增加，三点弯曲强度提高，而断裂韧性在３％Ｔｉ（质量百分数）时具有最大值，为６．２ＭＰａｍ１２．断口形貌分析表明，复合材料的增韧机理为桥接机理     

机械合金化制备γ—TiAl＋Ti2AlNl纳米复合材料

研究了Ｔｉ５０Ａｌ５０混合粉末在氮气氛的机械合金化过程，球磨３０ｈ后Ｔｉ５０Ａｌ５０混合粉末已形成非晶合金；经适当的热处理，可原位形成纳米复合材料γ－ＴｉＡｌ＋Ｔｉ２ＡｌＮ。     

Al2O3／Ni—Ti钎料／Nb的封接及其组织和性能的研究

探讨了用Ｎｉ－Ｔｉ高温合金对Ａｌ２Ｏ３陶瓷与金属Ｎｂ的封接行为．结果表明，Ｎｉ－Ｔｉ钎料对Ａｌ２Ｏ３陶瓷有良好的润湿性及高的焊后界面强度．钎料中的Ｔｉ与Ａｌ２Ｏ３中的Ｏ在反应界面上富集和结合是两种材料实现连接的原因．Ｎｂ溶入钎料中对减弱界面残余应力、提高强度有利     

机械合金化制备γ－TiAl＋Ti_2AlN纳米复合材料

研究了Ｔｉ_（５０）Ａｌ_（５０）混合粉末在氮气氛的机械合金化过程。球磨３０ｈ后Ｔｉ_（５０）Ａｌ_（５０）混合粉末已形成非晶合金；经适当的热处理，可原位形成纳米复合材料γ－ＴｉＡｌ＋Ｔｉ_２ＡｌＮ。     

316L粉末热等静压致密化过程数值模拟

为研究金属粉末热等静压（HIP）的致密化行为,采用Perzyna黏塑性流变模型,用有限元软件（MSC.Marc）实现316L粉末HIP过程的数值模拟.分析了粉末体在不同时刻的流动行为,同时研究不同阶段的致密化机制、压坯最终相对密度的分布及其变形.与试验结果对比表明：压坯的相对密度分布、变形趋势与试验结果符合得较好,尺寸...     

3%C-Cu机械球磨复合粉末的烧结

为了给后续的致密化工序(如热挤压)提供较高质量的烧结坯,用扫描电镜和光学显微镜分析了3%C-Cu机械球磨复合粉末所制备烧结坯的显微组织,并研究了工艺参数对其相对致密度的影响规律.结果表明,烧结温度对未机械球磨混合粉烧结行为的影响很大,而机械球磨复合粉对烧结温度不敏感.真空热压烧结可以明显地促进致密化过程.提高烧结温度、延长烧结保温时间或增加热压压强,均有助于提高烧结坯的相对致密度.在相同条件下,烧结坯的相对致密度随着复合粉末机械球磨时间的延长而降低.     

金属钛的离子注入表面改性

讨论了离子注入表面改性技术在生物材料中的应用，研究了Ｔｉ－６Ａｌ－４Ｖ合金表面注入Ｎ＋离子后的摩擦磨损行为，结果表明，Ｔｉ－６Ａｌ－４Ｖ经离子注入后，摩擦磨损性能都大幅提高．     

稀释剂Al_2O_3对Al/TiO_2自蔓延高温合成反应影响的研究

在研究稀释剂Ａｌ＿２Ｏ＿３对自蔓延高温合成反应４Ａｌ＋３ＴｉＯ＿２＝３Ｔｉ＋２Ａｌ＿２Ｏ＿３的绝热温度及反应模式的影响的基础上，研究了稀释剂Ａｌ＿２Ｏ＿３对该ＳＨＳ反应过程的影响以及对合成Ｔｉ／Ａｌ＿２Ｏ＿３金属陶瓷复合材料组织结构的影响．结果表明，稀释剂Ａｌ＿２Ｏ＿３含量增加，ＳＨＳ反应所必需的预热温度提高，燃烧速率降低，且燃烧不稳定；制备的Ｔｉ／Ａｌ＿２Ｏ＿３金属陶瓷复合材料致密度下降，但产生裂纹的倾向减少．     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to