2A66铝锂合金时效行为的研究

通过DSC分析、硬度测试、拉伸测试、SEM和TEM检测等手段,研究了2A66铝锂合金时效组织和性能的变化.研究结果表明:对于同一时效温度,随着时效时间的延长,强度出现峰值;时效温度越高,出现峰值的时间越短.2A66铝锂合金最佳的峰值时效制度为165℃保温64h,此时合金获得了良好的强塑性结合,硬度为146 HB,抗拉强度为526.5MPa,屈服强度为448.9 MPa,延伸率为10.1%.165℃时效过程中合金的主要强化相为δ',θ'和T_1相,时效初期合金的主要强化来源为GP区、δ'和θ'相,峰值时效时合金的主要强化相为θ'和T_1相.     

基于人工神经网络的Cu与Mg低质量比Al-Cu-Mg合金时效强化预测模型

通过硬度检测和透射电镜(TEM)观察,研究低Cu/Mg质量比AL-Cu-Mg合金时效强化机理,建立神经网络预测模型,使其在实验条件范围内对时效力学性能进行有效预测.在实验基础上,采用Levenberg-Marqllardt算法训练神经网络,建立以时效温度与时间为输入参数和硬度为目标函数的函数关系.结果表明:预测值与实验结果吻合较好,并证明了网络的可靠性与泛化能力;当时效温度越高时,达到峰值时效的时间越短,峰值时效的硬度也越大;在160～190℃时效温度范围内,合金峰值硬度随时效温度的升高而下降,对应硬度峰值的时效时间缩短.     

QBe1.9 铍青铜分级时效工艺研究

系统研究了时效工艺对ＱＢｅ１９铍青铜硬度和晶界反应量的影响。结果表明，ＱＢｅ１９经常规一次时效后，其硬度峰值和理想的晶界反应量各自对应的时效温度不匹配；改分级时效后，硬度峰值和理想的晶界反应量与对应的时效温度相匹配。文中给出了ＱＢｅ１９弹性接插件的分级时效工艺在生产流程中的合理位置。     

时效温度对890MPa级含铜钢组织与性能的影响

根据纳米析出强化机制,设计了一种屈服强度为890MPa的超高强海洋工程用钢——NEU890钢.在相同固溶条件下,研究了时效温度对NEU890钢显微组织、室温拉伸性能、-40℃ Charpy冲击功的影响.用透射电子显微镜分析纳米级析出相分布,并计算出其强度贡献值.结果表明,固溶态试样屈服强度为852MPa,500℃时效屈服强度达到峰值1026MPa,呈现典型时效析出强化特征.NEU890钢的脆性时效温度区间为300~500℃.当时效温度为550~600℃时,NEU890钢的屈服强度为994~910MPa,-40℃冲击功为108~166J,可满足EQ91钢拉伸和冲击性能指标要求.     

触变成形AZ91D镁合金的固溶和时效热处理研究

对触变成形AZ91D镁合金件进行了不同条件的热处理研究．研究结果表明，触变成形镁合金件经固溶处理后，共晶相的分解使合金的硬度值明显下降．固溶体过饱和程度越大，则时效强化效果越明显．触变成形镁合金件与普通压铸件有着相似的时效硬化特征：其强化原理也是β相的非连续与连续析出导致合金的力学性能提高．时效温度对β相的析出数量、形貌变化有显著的影响；当时效温度较高时，达到硬度峰值的时间明显提前；当温度较低时，达到峰值时间相对较长，但峰值的大小较前者高．     

喷射成形Al-Zn-Mg-Cu系超高强度铝合金热处理制度的实验研究

研究了喷射成形Al-Zn-Mg-Cu系超高强度铝合金的沉积态和挤压态的组织，对挤压态合金进行了固溶处理和时效处理，得到了时效硬度曲线，并进行了力学性能测试．结果显示：沉积态合金孔隙较多；挤压态合金内存在大量的颗粒，经能谱分析为富铜相；固溶温度达到490℃时，晶界出现熔化现象．时效硬度曲线表明：采用120℃时效，在15～25h之间达到硬度峰值；采用135℃时效，达到硬度峰值的时间与合金的成分有关，随着Zn含量的增加，达到硬度峰值的时间变短，而抗拉强度基本稳定在700MPa左右．     

冷变形后微合金钢碳氮化物的析出与组织

通过固溶时效处理，研究冷变形、时效温度等因素对微合金元素V，Ti，Nb的碳氮化物沉淀析出行为和组织演变过程的影响。结果表明：预变形试验钢的时效动力学曲线和未变形试验钢的时效动力学曲线具有相似的形状，预变形后达到的硬度峰值高，所需的时效时间缩短。预变形对含钒钢和含钛钢的碳氮化物析出动力学的影响很小，组织发生了再结晶并生成铁素体组织。预变形促进了含铌钢的碳氮化物较快析出，阻止再结晶，保持粒状贝氏体组织。     

2种时效制度对2A97合金组织和性能的影响

研究2种时效制度对2A97合金组织性能的影响.研究结果表明:塑性指标随时效温度提高和时效时间延长而降低;对于同一时效温度,随着时效时间的延长,强度出现峰值,时效温度越高,出现峰值的时间越短;时效前适当的预变形可以增加位错密度,为θ'相和T1相提供更多的形核点,使时效析出相数目增多,析出相尺寸细化,从而保证合金具有良好塑性的同时有较高的强度;2A97合金的峰值时效制度是在165℃保温60 h,最佳应变时效制度为预变形6%后在135℃保温60 h.     

喷射成形及时效处理对Cr12MoV钢组织及性能的影响

采用喷射成形技术制备了Cr12MoV钢,应用金相、X射线衍射分析、差热分析等实验手段对该钢的微观组织及性能进行了分析和研究.结果表明,喷射成形Cr12MoV钢的显微组织得到了显著的细化,与Cr12MoV钢铸态组织不同处在于其主要由奥氏体组成,由于喷射成形过程中的冷却速度快,奥氏体中高度固溶了碳及合金元素,其晶格常数达0.3620nm,且喷射成形钢的马氏体起始转变温度(Ms)亦低于常规工艺制备的钢的Ms.随着时效温度的升高,亚稳奥氏体逐渐发生了转变,Cr12MoV钢的硬度在570℃时效温度处出现峰值,由时效处理前的HRC38增大至HRC60,时效合金主要由马氏体构成.当时效温度高于570℃时,Cr12MoV钢的硬度剧烈下降,因此,570℃是喷射成形Cr12MoV钢进行时效处理的临界温度.     

喷射成形及时效处理对Cr12MoV钢组织及性能的影响

采用喷射成形技术制备了 Cr12 Mo V钢 ,应用金相、X射线衍射分析、差热分析等实验手段对该钢的微观组织及性能进行了分析和研究 .结果表明 ,喷射成形 Cr12 Mo V钢的显微组织得到了显著的细化 ,与 Cr12 Mo V钢铸态组织不同处在于其主要由奥氏体组成 .由于喷射成形过程中的冷却速度快 ,奥氏体中高度固溶了碳及合金元素 ,其晶格常数达 0 .362 0 nm,且喷射成形钢的马氏体起始转变温度 (Ms)亦低于常规工艺制备的钢的 Ms.随着时效温度的升高 ,亚稳奥氏体逐渐发生了转变 ,Cr12 Mo V钢的硬度在 570°C时效温度处出现峰值 ,由时效处理前的 HRC38增大至 HRC60 .时效合金主要由马氏体构成 .当时效温度高于 570°C时 ,Cr12 Mo V钢的硬度剧烈下降 .因此 ,570°C是喷射成形 Cr12 Mo V钢进行时效处理的临界温度 .     

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.     

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.     

A computer generator for randomly layered structures

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