高强高导Cu-Cr-Zr系合金的研究现状

从合金成分设计、析出相结构和制备技术三方面综述了高强高导Cu-Cr-Zr系合金的研究现状.在分析多种元素对合金强度影响的基础上,重点讨论了稀土元素的作用,适量稀土的加入能同时提高合金的硬度和电导率.Cu-Cr-Zr系合金的析出相主要是Cr和CuxZr（x=3,4,5）相,且合金在470 ℃时效4h形成有序的原子排列,其化合物类型为CrCu2（Zr,Mg）.固溶形变时效强化技术和快速凝固技术与常规固溶时效处理相比都能大大提高合金的综合性能.该类合金今后应向多元微合金化方向发展,尚待解决的主要问题是Zr、稀土等易烧损元素的熔炼较难控制.     

Cu-Ni-Si-Cr合金时效处理后的组织与性能

研究了时效与时效前的冷变形对Cu-2．37Ni-0．58Si-0．39Cr合金时效后硬度及导电率的影响，结果表明：合金经920℃固溶处理后，在500℃时效时可获得较高的硬度，而在550℃时效可得到较高的导电率；合金时效前的冷变形可加速时效析出，试样经80％变形后，在500℃时效1h，显微硬度可达HV271，而固溶态直接时效仅为HV239。合金在时效析出过程中有两种类型的析出相，分别为Cr3Si和Ni2Si。     

时效对Cu-Cr-Zr合金显微硬度及导电率的影响

探讨了时效工艺及形变量对Cu 0 .3Cr 0 .15Zr合金显微硬度及导电率的影响。结果表明 ,合金经 92 0℃固溶处理后在 4 2 0℃及 4 6 0℃时效可分别达到较好的硬度和导电率 ,分别达 183HV和 6 8%IACS ;时效前对合金加以适当冷变形可加速合金时效析出过程。影响合金导电率的主要因素是基体中固溶元素的含量 ,含量越高 ,导电率越低 ,反之则越高。而时效前冷变形可以增加合金内部位错等缺陷的数量 ,加速了合金第二相的析出。     

Ti_(30)Nb_5Ta_6Zr合金的组织和力学性能研究

根据β稳定化系数kβ和d-电子理论,采用无细胞毒性合金元素Nb、Ta、Zr,设计了具有低弹性模量的新型牙科种植用近β型Ti30Nb5Ta6Zr合金,研究了合金经不同温度固溶和时效处理后的显微组织和力学性能.结果表明,合金固溶后在低温时效时析出ω相导致合金脆性.随时效温度升高,析出相由ω逐步变为α并发生粗化,使合金强度降低,但塑性得到改善.固溶温度过低（700℃）,时效后强度较低 固溶温度过高（850℃）,导致合金出现β脆性.合金在750℃固溶和500℃时效12h后强韧性好,弹性模量低于现有Ti29Nb13Ta4.6Zr合金,综合力学性能可满足牙科种植合金的要求.     

形变热处理对Cu0.3Cr0.1Zr合金上引铸坯杆组织性能的影响

通过对上引Cu-0.3Cr-0.1Zr合金固溶处理、冷拉拔以及随后的时效处理工艺,研究冷拉拔形变及时效对材料力学性能、导电性能及组织结构的影响规律.结果表明:时效前的冷拉拔变形能提高Cu-0.3Cr-0.1Zr合金的力学性能而保持较高的导电率;合金在950 ℃固溶1 h后,经70%冷拉拔变形和500 ℃时效4 h,合金抗拉强度和导电率分别达到了418 MPa和87 %IACS;时效合金组织转变过程为:固溶体→G.P.区→Cr+Cu₄Zr,析出相对位错运动的阻碍是合金强化的重要机制.     

时效处理对Cu-Cr-Ti合金组织与性能的影响

由于高强、高导Cu-Cr-Zr合金在工业化生产熔炼时不易控制Zr的收得率,通过采用Ti替代Zr,以期获得易熔炼以及性能与Cu-Cr-Zr合金相当的时效强化型Cu-Cr-Ti合金。采用真空感应熔炼技术,经过热锻、固溶、冷轧、时效共4道工序,制备了Cu-Cr-Ti合金板材;对时效后的Cu-Cr-Ti合金的组织状态、析出相形态、析出相与基体的界面关系进行了分析;对合金的抗拉强度和导电率进行了测试。结果表明：450 ℃时效60 min后,Cu-0.45Cr-0.14Ti合金的综合性能最佳,抗拉强度和导电率分别达到620 MPa和64.9 %IACS;Cu-0.45Cr-0.14Ti合金中纳米尺寸的Cr强化相呈现椭圆形和双花瓣形,2种形状的析出相粒子均为面心立方结构,且均与基体保持完全共格关系。     

固溶时效对Cu-17Zn-0.4Cr合金硬度的影响

文章通过不同的热处理工艺来研究固溶时效对Cu-Zn-Cr合金硬度的影响.结果表明,经920 ℃、1 h固溶,再经475 ℃、1 h时效,合金的硬度能达到最大值120.5 HV.X射线衍射和扫描电镜研究表明,经920 ℃固溶475 ℃时效后,Zn在合金中与铜形成单相的α固溶体基体;有少量Cr在固溶过程中未溶入基体,此Cr粒子尺寸粗大;大多数Cr粒子为时效过程析出,在基体上呈细小弥散分布,这部分析出的Cr粒子是合金强化的主要原因.     

时效工艺对Cu-Ag-Zr合金电磨损性能的影响

对Cu-0．1Ag-0．18Zr合金时效后的电导率、显微硬度以及电滑动磨损性能进行了研究。结果表明：该合金940℃固溶1h后，在560℃时效可获得较高的电导率，在480℃时效可获得较高的显微硬度。时效前冷变形能大大加快第二相的析出过程，使合金综合性能显著提高。该合金经940℃固溶再经60％变形后，在480℃时效1h，其电导率和显微硬度分别可达85．6％IACS和HV131．2，而固溶后直接时效为81．3％IACS和HV116．1。在载流条件下，合金的磨损量随加载电流的增加而增大；磨损机制是以电蚀为主的电蚀、犁削和磨粒磨损。     

节镍无磁不锈钢Cr18Ni6Mn3N的组织及性能

研究了节镍无磁不锈钢Cr18Ni6Mn3N的热轧及固溶后的力学性能和耐蚀性能,分析了其固溶和时效析出后的组织演变规律、冷变形过程中形变诱发马氏体相变及其磁性能.结果表明:该不锈钢的固溶组织为单相奥氏体,其力学性能和耐蚀性能均高于SUS304不锈钢;800℃保温4 h后,在晶界析出粒状氮化物,随着保温时间延长,逐渐沿晶界凸起片层状析出物并向晶内生长,保温20 h后,凸出的片层状析出物直径达20μm.冷轧压下率18.3%时尚未发现形变诱发马氏体组织,随着变形量增大,马氏体含量增多,磁导率上升,但与相同条件下的SUS304不锈钢相比,冷轧板固溶后相对磁导率可降至1.002,因此可用于低成本无磁不锈钢领域.     

Al-Zn-Mg-Sc-Zr合金板材制备过程中组织性能的演变

采用拉伸力学性能、硬度、电导率测试以及X线衍射(XRD)物相分析和电子显微分析技术研究Al-Zn-Mg-Sc-Zr合金板材在制备过程中的组织性能演变.研究结果表明:铸态合金在350℃/8 h单级均匀化处理过程中析出细小弥散的Al3(Sc,Zr)粒子,但同时也析出大量粗大T相,合金过饱和度降低,强度下降;在350℃/8h+470℃/24 h双级均匀化第二级过程中,T相回溶入基体,而Al3(Sc,Zr)粒子特性基本上没有发生变化;由于Al3(Sc,Zr)粒子的抑制再结晶作用,合金热轧、退火以及冷轧后固溶状态下为纤维状变形组织;时效后合金析出大量细小弥散分布的η’相,具有很强的强化效果.     

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

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.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

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。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.     

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.