消除7A05铝合金板材各向异性的热处理工艺

为提高7A05铝合金热轧板材的综合力学性能并减少各向异性,对7A05铝合金固溶、预时效、时效和形变处理等工艺对性能的影响进行了系统的研究. 比较了供货态、形变态、回归(RRA)态和采用预时效形变热处理的优化态热处理工艺对综合力学性能的影响. 结果表明:固溶的最佳温度为480 ℃,单级时效最佳工艺为120 ℃,24 h,双级时效中第一级时效最佳工艺为90 ℃,8 h,最佳形变为25%. 通过金相组织和力学性能测试结果表明:由于预时效析出促进形变热处理时亚晶等轴化,优化态强度高,进一步改善了合金性能,减少了轧制板材纵横向力学性能各向异性倾向.     

CuCrSnZnCe合金的耐热性能

研究了不同形变热处理工艺对引线框架用CuCrSnZnCe合金的硬度和软化温度的影响,分析了固溶温度和精轧变形量对合金耐热性的影响。通过研究不同温度下退火1 h后合金的组织变化,分析了合金软化的原因。研究结果表明:经过920℃固溶1 h、40%冷变形,在500℃时效2 h、再进行40%冷变形,480℃时效1.5 h、最后进行20%精轧等多次变形时效工艺后,合金具有较好的耐热性能,硬度为177HV,软化温度达518℃。     

新型高强Al-Mg-Si合金热处理工艺

结合力学性能测试、扫描电镜分析、DSC热差分析和金相组织观察,对一种新型高强Al-Mg-Si合金挤压材的固溶与时效制度进行了系统研究.同时得到了该合金挤压材不同时效温度下的力学性能,为工厂实际生产中热处理规程的制定以及深入研究提供详细的参考依据.该挤压材过烧温度572℃,熔化温度为594℃;对其进行560℃/2h固溶处理后,以及170℃/12 h人工时效热处理,可达到最佳峰值时效效果,其抗拉强度、屈服强度和延伸率可依次达到406,340 MPa和18.37%;该合金挤压材发生了充分的再结晶,致使加工硬化完全消除.     

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.     

形变热处理对2197铝锂合金组织和性能的影响

对2197合金进行形变热处理,通过力学性能试验和TEM观察分析了不同时效阶段合金的力学性能和微观组织,研究了形变热处理对2197合金的组织和性能影响,结果表明:形变热处理2197合金峰时效时主要析出相为尺寸为50～150nm分布均匀的T1相。形变热处理为T1相的非均匀形核提供了优越的形核场所,促进了T1相的析出及长大,减少了2197合金达到峰时效的时间;长宽比较大的T1相的强化效果大于δ′相和θ′相,形变热处理还可以提高2197合金的峰时效强度。     

使役条件下热暴露对2124-T851铝合金显微组织与性能的影响

采用室温拉伸性能测试、金相和透射电子显微分析方法研究热暴露温度和时间对30 mm厚2124-T851铝合金板材组织与力学性能的影响.研究结果表明:在高于板材190℃最终时效温度下热暴露,合金强度下降而伸长率上升,温度愈高、时间愈长,强度下降和伸长率上升就愈快,于250℃热暴露50 h和100 h时,屈服强度分别降低53%和58%,伸长率分别上升约23%和55%;低于最终时效温度热暴露,若热暴露温度在150℃以下,则合金拉伸力学性能变化不大;当热暴露温度接近最终时效温度,如175℃时,若热暴露时间在100 h以内,则合金拉伸性能变化也不大;若热暴露时间超过100 h,则合金强度和塑性均有所下降.于175℃热暴露500 h屈服强度和伸长率就分别降低14%和9%;于热暴露条件下,2124-T851合金拉伸性能衰退的主要原因是合金固溶体基体内主要强化相S'(Al2CuMg)相粗化以及晶界无沉淀析出带的宽化.     

时效状态对Cu-Cr-Zr系合金性能的影响

采用不同时效状态和随后形变热处理工艺制备了Cu-Cr-Zr系合金,采用微观组织观察、硬度和导电率测试等手段研究了不同时效状态对双级时效Cu-Cr-Zr系合金性能的影响.结果表明：欠时效+冷轧+时效工艺和峰时效+冷轧+时效工艺制备的Cu-Cr-Zr-Mg-Si和Cu-Cr-Zr-Ni-Si合金均可获得力学性能和电学性能的优良组合.其中：欠时效+冷轧+时效工艺所制备的合金综合性能更优,但加工热处理过程中性能变化剧烈,材料生产过程中性能均匀性不易控制;峰时效+冷轧+时效工艺制备的合金综合性能极其稳定,易于在生产中控制.不同工艺下的合金性能差异是由析出相与位错的交互作用机制不同造成的.     

微合金化与形变热处理对足金强度的影响

采用力学拉伸试验、透射电镜及扫描电镜等测试分析手段,较系统地研究了微合金化与形变热处理对足金拉伸性能和断裂行为的影响.结果表明,含微量合金元素X1的足金,85%冷加工变形,260℃时效2～3h,出现强度峰(σb为680MPa).含微量元素X1和X2的足金主要强化方式是细晶强化、加工硬化与时效强化,其断裂行为是微孔聚集型断裂     

预变形对7N01铝合金力学性能及显微结构的影响

采用力学性能测量和显微结构表征和工艺调控等手段,系统研究了预变形加时效的组合工艺对7N01铝合金力学性能和显微结构的影响.研究表明:与单一的变形强化工艺和单一的时效强化工艺相比,合适的形变时效工艺能大幅提高材料的性能.本实验采用10%预变形后120℃再时效,合金的屈服强度可以达到430 MPa,抗拉强度可以达到470MPa,延伸率仍然保持在14%.随着预变形量的增加,合金的强度先上升后下降,采用过大的变形量反而不利于优化材料力学性能;变形引入的位错会对后续时效强化中纳米析出相颗粒的种类、尺寸和分布等产生关键作用,从而影响材料最终的综合力学性能.     

形变时效工艺对低铍Cu-Ni-Be合金力学性能和电导率的影响

运用正交设计研究形变时效工艺(冷变形量、时效温度和时效时间)对低铍含量Cu-Ni-Be合金力学性能和电导率的影响,并通过光学显微镜、扫描电镜和透射电镜对其显微组织进行分析。研究结果表明:在形变时效处理的3个主要工艺参数中,时效时间对抗拉强度、屈服强度和相对电导率的影响最大,时效温度次之,冷变形量最小;合金在经过37.5%冷变形的轧制后,在470℃时效2h,γ″析出物细小且弥散分布在基体中,合金具有较好的综合性能。     

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.     

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.     

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.     

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。     

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.