纳米晶低钼高铁Fe-Ni-Mo合金的制备及其微观结构

在酸性柠檬酸盐镀液中电沉积制备低Mo高Fe含量的Fe-Ni—Mo合金；采用扫描电镜、X射线衍射仪和X射线能谱仪对镀层微观结构、表面形貌及组成进行分析。结果表明：工艺条件和钼酸钠浓度对合金组成的影响较大;所得合金晶粒尺寸为6．2～12．7nm，并随电流密度、温度和电镀液的pH值的改变而变化；合金的晶体生长符合晶核三维生长模型，镀层表面形貌由平行和垂直于基体的生长速度的相对大小决定；镀层物相为固溶体和金属间化合物的多相结构，当电流密度为3A／dm^2时，镀层物相由FeNi（BCC）和FeMo固溶相转化为FeNi（FCC）和MoNi4多相结构；镀层的应力随晶粒尺寸的减小呈线性增大；合金镀层的点阵常数发生了畸变。     

铝酸盐体系中镁合金微弧氧化膜的性能

利用交流微弧氧化装置对铝酸盐体系中的AZ91D镁合金进行了微弧氧化处理，并通过扫描电镜、表面性能测试仪和电化学测试技术等研究了氧化时间和电流密度对微弧氧化膜层表面形貌、厚度、耐蚀性、摩擦磨损性能和结合力的影响．实验结果表明，随着氧化时间和电流密度的增大，在铝酸盐体系中镁合金微弧氧化膜层表面微孔的数量减少，但微孔直径和表面粗糙度增大．微弧氧化膜层的厚度约为4-16μm；膜层与基体的结合力均在20N以上．微弧氧化膜层的耐磨性和耐蚀性随氧化时间和电流密度的增大呈先升高后降低的趋势．镁合金在铝酸盐体系中微弧氧化处理的最佳工艺为氧化时间40min、电流密度0．20A／cm^2.     

非水溶液四氢呋喃有机体系铜基电镀铝的研究

主要对AlCl3和LiAlH4溶于四氢呋喃有机体系镀层的表面形貌、电镀参数、温度以及镀层的厚度进行了研究.结果表明:当电流密度或电压低时,核密度低,形变能是控制颗粒形状的主要因素,析出铝颗粒呈碟状;当电流密度或电压高时,核密度高,表面能成为主导因素,铝颗粒呈球状.实验结果还表明,电流密度或电压是影响形核密度和颗粒形貌的关键因素.采用此方法可以获得平滑、光亮、致密与基体附着良好的镀层.     

苯基TMPAC-AlCl3离子液体电镀铝研究

采用以苯为助溶剂的TMPAC-AlCl3季铵盐室温离子液体,在铜上电镀铝.探讨了电流密度和电镀时间对镀铝层表观形貌和阴极电流效率的影响;通过极化曲线评价了镀铝层的耐蚀性,并采用扫描电镜,能量弥散X射线谱仪和X射线衍射仪等手段对样品进行表征.结果表明,在电流密度为15 mA/cm2,电镀时间为30 min条件下获得的镀铝层表面致密,阴极电流效率最高,达92%.阴极电流效率随电镀时间延长而下降,主要原因为AlCl3在Al阳极表面上的析出.极化曲线测试表明,镀铝层越厚,镀层的耐蚀性越好;厚度达17μm的镀铝层具有阳极钝化行为,可有效地保护基体.     

AlCl3-NaCl-KCl熔融盐中铝的电沉积

在摩尔比为0.66:0.17:0.17的AlCl3-NaCl-KCl共融盐中,控制阴极电流密度在基体铁片上获得银白色铝镀层.用扫描电镜、X射线物相分析对所得镀层进行显微组织分析,并用循环伏安法研究熔融盐中铝沉积的机理.研究结果表明:当电流密度为25 mA/cm2时,所得铝晶粒为针状,以(200)面构成为主;当电流密度为40 mA/cm2时,最大电流效率达到92%;当电流密度超过80mA/cm2时,电流效率随电流密度的增大急剧减小;当电流密度增至60 mA/cm2时,所得晶粒既有针状也有球形,以(111)面构成为主;当电流密度为100 mA/cm2时,所得铝晶粒呈球形;所得铝镀层厚度与电镀时间呈抛物线关系,与电流密度呈直线关系;熔融盐中沉积铝源于Al2Cl7-的还原,还原峰电位为-0.23 V.     

3％NaCl溶液中55％Al－Zn－1．6％Si合金镀层电化学参数测定及电偶腐蚀的电化学行为

提出了一种弱极化曲线测量数据计算机处理方法，并计算了５５％Ａｌ－Ｚｎ－１．６％Ｓｉ合金镀层在３％ＮａＣｌ溶液中腐蚀过程的电化学参数，研究了镀件在３％ＮａＣｌ溶液中发生整体腐蚀加速的机理．结果表明，镀层表面微电偶局部腐蚀的发展形成了基体钢与镀层金属的宏观电偶腐蚀，电偶电位Ｅｇ随时间的正移，使镀层金属的溶解电流密度迅速增大，钢基体受到的保护效应减小．     

ZL102表面直接化学复合镀Ni-P-SiC镀层的结构与性能

采用直接化学复合镀法在铸铝102合金表面制备Ni-P-SiC复合镀层,利用XRD、扫描电镜等对镀态复合镀层的结构和形貌进行分析,并对镀层的显微硬度、结合力及耐蚀性进行测试.结果表明:镀层表面平整均匀;复合镀层中SiC微粒分布均匀且复合量较高,镀层厚度均匀、致密;复合镀层相结构更类似于非晶态;镀层镀态显微硬度可达823.8HV;镀层与基体结合较好,且复合镀层极大地改善了基体的耐蚀性.     

环保型低浓度硫酸盐三价铬电沉积厚铬的研究

通过大量试验研制了一种甲酸盐-羧酸盐作配位剂的低浓度(Cr3+含量仅为15.5g/L)硫酸盐三价铬电沉积厚铬工艺.优化后的工艺光亮电流密度范围在3.5～25A/dm2以上、铬的最高沉积速率达0.26μm/min、覆盖能力60.5%.该镀液稳定性好,且在较长时间内能保持较高的沉积速率,沉积2h镀层厚度达23.6μm.镀层表面瘤状凸起密布、无裂纹、呈非晶态、与基体结合力好、孔隙率为零、耐蚀性良好.     

镀液温度对脉冲电镀镍-铬-钼合金镀层的影响

采用脉冲电镀法在Q235钢表面制备了Ni-Cr-Mo合金镀层,利用辉光放电光谱仪(GDS)、扫描电子显微镜(SEM)、Tafel曲线和电化学阻抗谱(EIS)考察了镀液温度对镀层元素含量、沉积速率、表面形貌和耐蚀性的影响。结果表明,随镀液温度的升高,镀层镍含量减小,铬含量先增大后减小,钼含量增大;镀层沉积速率稍有增大,镀层表面颗粒尺寸增大,镀层在3.5%NaCl溶液中耐蚀性先增强后减弱;镀液温度为30℃时,镀层最为均匀致密,且具有最大的自腐蚀电位(-0.535V)、最小的腐蚀电流密度(0.123μA·cm~(-2))和最大的电荷转移电阻(2550Ω·cm~2),耐蚀性最好。     

Fe2+浓度对20号钢表面电镀Fe-Ni合金镀层的影响

采用电沉积技术在20号钢表面制备了Fe--Ni合金层,考察了镀液中Fe2+浓度对合金镀层沉积速度、镀层成分、相结构、镀层显微硬度和耐蚀性的影响规律,并探讨了耐蚀机理.实验结果表明:电镀Fe--Ni合金可获得纳米晶结构,随镀液中Fe2+浓度增加,镀层中含铁量增大;镀层显微硬度的变化与Fe原子在Ni晶格中有序固溶程度有关;Fe--Ni合金镀层的耐蚀性均优于20号钢,当镀液Fe2+浓度为0.01 mo.lL-1时,获得镀层具有最佳的耐蚀性.随镀层中铁含量增加,具有钝化特性的高含Ni的Fe--Ni相含量减少,耐蚀性下降,但该相纳米结构显著细化,加速钝化可提高耐蚀性,这一对矛盾导致镀层耐蚀性与铁含量间没有明显的变化规律.高孔隙率也是耐蚀性下降的原因之一.     

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。     

《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     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with