低压等离子喷涂NiCOCrAlYTa涂层的组织结构及抗氧化性能

采用低压等离子喷涂在Co基高温合金K640基体上制备NiCoCrAlYTa涂层,通过XRD,SEM和EDS等方法研究低压等离子喷涂涂层和真空退火后涂层的形貌、相结构及抗氧化性能.研究结果表明:低压等离子喷涂涂层主要由γ-Ni,γ'-AlNi3和极少量的β-NiAl等相组成,元素分布均匀,涂层为典型的片层状结构,沉积界面处存在少量孔洞:真空退火处理过程促进了β-NiAl相的析出,衍射峰尖锐,元素分布不均匀,Al和Y向涂层表面扩散,Cr富集于涂层与基体的界面处;真空热处理涂层表面在氧化初期形成较多孔洞,导致涂层抗氧化能力降低.     

陶瓷涂层/GH202合金界面显微组织的演化

航天发动机工作时,要求燃气通道内表面具有优越的抗高温、抗氧化性能和良好的机械性能.作者在GH202合金制备的火箭发动机关键零件表面加涂高温无机涂层,并通过光学显微镜、扫描电镜、能谱分析及硬度测试,观察和分析了涂层/GH202合金界面显微组织的演化.研究结果表明GH202合金表面高温无机涂层经历了1000℃25℃的50次热循环后,涂层无崩裂、脱落现象,涂层与基体结合牢固,性能良好.在1000℃时的扩散退火过程中,合金中的Cr元素向涂层/基体合金界面扩散,在涂层一侧形成富Cr元素的化合物层,在基体一侧形成富Ti,Al元素的晶间氧化物层;涂层中主要元素Si向金属基体中扩散.为提高涂层与基体合金的结合强度以及涂层的热腐蚀性能提供了依据.     

钨合金/不锈钢的低温扩散连接及界面组织性能

通过低温扩散连接方法实现钨合金(90W-7Ni-3Cu)与304不锈钢的高性能连接。采用扫描电镜(SEM)、能谱(EDS)、电子探针(EPMA)分析连接界面的微观组织及元素扩散与分布行为,采用拉伸试验测试连接界面的力学性能。研究结果表明：在800～950℃、压力20 MPa、保温120 min的条件下,可以实现90W-7Ni-3Cu合金与不锈钢的有效连接;当连接温度为900℃时,连接界面抗拉强度达到最大值168 MPa;连接界面结合紧密,无裂纹等缺陷。钨合金与不锈钢界面原子形成了充分的互扩散,不锈钢中的W、Fe、Cr、Ni和Si元素借助空位以及点缺陷扩散到了钨合金一侧的钨中,形成了富含W、Fe、Cr、Ni和Si元素的扩散层。900℃连接样件的断裂发生在钨合金一侧,可以观察到钨合金基体的六角形晶界并且其表面覆盖有粗糙的黏着物,黏着物为原子扩散所形成的扩散层。不锈钢中的Cr、Fe元素以固溶的方式扩散到了钨合金的(Ni,Cu)相中,提高连接界面强度。     

NiCrAlY涂层/TC4基体界面反应机理

采用电弧离子镀技术在TC4(Ti6Al4V)合金基体表面沉积制备NiCrAlY涂层.通过扫描电镜与能谱分析、X射线衍射分析及显微硬度测试,研究真空热处理对NiCrAlY涂层组织性能的影响;分析界面反应产物的形成过程;讨论Cr元素在界面反应中的作用机制.研究结果表明:真空热处理后NiCrAlY涂层中有γ'-Ni3Al相析出,提高了涂层的表面硬度;在870℃以下热处理,NiCrAlY涂层/TC4基体界面反应产物的出现顺序依次为:相变影响区→Ni3(Al,Ti)和Ti2Ni化合物层→TiNi化合层;Cr元素在870℃以上开始扩散并参与界面反应,形成TiCr2化合物.     

316L-20G双金属复合管焊缝组织元素扩散分析

通过对20G钢内衬316L金属复合管的焊缝区、316L基体以及20G钢进行EDS元素扫描,再采用扫描电镜对316L焊缝区、20G钢焊缝区进行线扫描分析,对焊缝组织主要合金元素的扩散进行了研究。结果表明：焊缝过渡层中合金元素被碳钢稀释,碳原子向316L和焊缝扩散,同时316L和焊丝中的合金元素Cr、Ni也向碳钢中渗透,但过渡层起到了良好的隔离作用,致使316L不锈钢金属中合金元素含量没有明显降低,保持了316L母材耐腐蚀性能。     

纳米晶镍涂层与基体的界面扩散研究

在不同温度下（150℃～500℃）对电沉积纳米晶镍镀层与低碳钢基体进行低温扩散退火热处理。利用扫描电子显微镜（SEM）的背散射电子（BSE）像及附带的能量色散谱（EDS）考察了热处理后样品中涂层与基体界面上的相结构变化及过渡层的形成。结果表明,在250℃－500℃范围进行低温扩散退火可以有效促使纳米晶镍涂层与基体界面上原子的互扩散,形成扩散过渡层,同时界面上形成了新的相结构。     

GH4169合金高温疲劳裂纹扩展的微观损伤机制

空气环境对高温合金在高温下的损伤行为有显著影响.为了研究标准热处理态GH4169合金在高温疲劳裂纹扩展过程中的微观损伤机制,在空气环境中进行650℃、初始应力强度因子幅ΔK=30MPa·m1/2和应力比R=0.05的低周疲劳裂纹扩展试验.使用扫描电镜(SEM)及能谱(EDS)对试样的断口、外表面和剖面进行观察和分析.实验结果表明:疲劳主裂纹以沿晶方式萌生并扩展,随后沿晶二次裂纹出现,并且其数量和长度沿主裂纹方向逐渐增加,进入快速扩展阶段后,断口呈现韧窝组织形貌;在裂纹扩展过程中,δ相与基体的界面发生氧化,使得沿晶二次裂纹沿界面扩展并产生偏折,从而起到阻碍二次裂纹扩展的作用;试样外表面的主裂纹周围出现晶界氧化损伤区,其尺寸和晶界开裂程度沿主裂纹扩展方向逐渐增大.     

X80管线钢的高温氧化行为

利用热重法对X80管线钢高温氧化行为进行系统研究,分析不同温度下氧化增重和氧化铁皮形貌演变规律及合金元素在氧化层与钢基体界面处的分布规律.实验结果表明:700~1200℃范围内,X80钢氧化增重曲线呈现抛物线规律.此外,氧化铁皮厚度随温度升高而增加,特别是当温度高于800℃时,由于金属基体存在相变,氧化铁皮厚度急剧增加.高温条件下X80钢氧化铁皮为典型三层结构,外层为极薄的Fe₂O₃,中间层为Fe₃O₄,内层为粗大柱状晶FeO,并在靠近钢基体处形成一层晶粒细小的内氧化层,内氧化层阻碍了铁氧离子的相互扩散,提高了X80管线钢的高温耐蚀性.     

料浆喷涂微晶玻璃涂层的微观组织结构及其抗氧化性能

采用料浆喷涂法在镍合金GH140基体上制备SiO2-BaO-MgO-ZnO微晶玻璃涂层,研究微晶玻璃涂层在高温下的抗恒温氧化性能。通过SEM,EDS和XRD分析GC/GH140晶化处理及1 000℃恒温氧化前后的形貌特征、相组成以及元素分布的变化。研究结果表明:GC/GH140氧化质量增加极小。晶化热处理前,微晶玻璃涂层与GH140基体结合致密,在涂层烧结过程中,基体中的Cr和Ti向涂层界面扩散,形成富Cr和Ti致密氧化膜,并在基体中形成了一层很薄的氧化物不连续分布的过渡区域。晶化热处理2 h后,涂层中析出主要成分为白色柱状BaSi4O9和黑色SiO2颗粒,氧化膜与过渡层的厚度变化不大。随恒温氧化时间延长,涂层的相组成保持不变,黑色SiO2相含量迅速增加,过渡层厚度缓慢增加;氧化96 h后,涂层与基体仍然结合良好,表面也十分致密,有效阻碍了氧的扩散,大幅度提高了基体的抗氧化能力。     

Be/Cu/HR-1不锈钢扩散连接界面特性

以Cu为中间层材料,采用Greeble1500热模拟试验机对Be/HR-1不锈钢进行扩散连接试验,利用PME Olympus Tokyo光学显微镜、扫描电镜(SEM)、显微硬度计(HV-1000)、X射线衍射仪研究分析了其界面特性.研究表明,Cu层过渡材料能有效阻碍Be和Fe之间的互扩散以及阻挡不锈钢中合金元素Ni、Cr等向铍基体的扩散,从而阻碍了它们之间金属间化合物在扩散区内的形成,但它也带来了新的金属间化合物如Be2Cu;金属间化合物优先沿晶界生成,呈三维网状分布;元素的扩散主要沿晶界进行,且扩散不是各个部位均等的向前推进,也没有单一的金属间化合物薄层形成;试样的断裂位置在Be/Cu界面处.     

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。     

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.     

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.     

The Analects and the Moment in Peking——The influence of a Confucian education system on the personality formation,the way of thinking and the fate of the main characters

0.Preface China has long been boasting of its colorful and immense culture which comprises of Taoism,Confucianism and Buddhism.The interwoven influence among the religions on Chinese way of thinking,on the nation＇s behavior in their social life throughout the long history is beyond list.