FeCo—SiO2颗粒膜的磁性和隧道磁电阻效应研究

利用射频共溅射的方法制备了不同金属含量的φ的Fe-SiO2金属－绝缘体颗粒膜,系统研究了薄膜的微结构、磁性以及隧道磁电阻（TMR）效应,在φ＝0．33处得到最大磁电阻比RTMR为－3．3％,在同样的制备条件下φ＝0．33,用Co取代Fe得到一系列的（Fe100-xCox)0.33(SiO2)0.67的颗粒膜,对其TMR的研究发现在x＝53时得到最大的磁电阻经为－0．43％,且Co对Fe的替代薄膜的微结构,由Inoue关于磁电阻 应的理论得到的自旋极化率P和Co的原子百分数x的关系曲线和实验测得的RTMR－x曲线具有相似的变化趋势,表明在FeCo-SiO2膜中由于磁性颗粒自旋极化率P的提高而使RTMR变大,这也和基于第一原理的线性缀加平面波方法得到的理论计算结果一致。     

Fe-Al_2O_3纳米颗粒膜的巨磁电阻效应及微结构

采用磁控溅射方法在玻璃基片上制备了一系列的 Fe- Al2 O3 颗粒膜样品 ,对样品的巨磁电阻效应 (GMR)和磁性能进行了测量 ,并用高分辨电镜 (HRTEM)对膜中 Fe颗粒的微结构进行观察 .结果表明 :磁电阻 MR随 Fe含量而变化 ,在体积分数为 47%时获得最大值 4.0 % .45 % Fe-Al2 O3 颗粒膜的室温磁性表现为超顺磁性 ,磁电阻 MR与 - (M/Ms) 2 成正比 ,相关常数 A≈ 0 .0 3 6 .HRTEM观察表明 ,当 Fe颗粒尺寸约小于 1 nm时 ,Fe颗粒为非晶态 ,而大于该尺寸时则为晶态 .在 Fe- Al2 O3 颗粒膜体系中存在与隧道相关的 GMR,GMR的起因可归于传输电子的自旋相关的散射     

Fe—Al2O3纳米颗粒膜的巨磁电阻效应及微结构

采用磁控溅射方法在玻璃基片上制备了一系的Fe-Al2O3颗粒膜样品,对样品的巨磁电阻效应（GMR）和磁性能进行了测量,并用高分辨电匀（HRTEM）对膜Fe枯粒的微结构进行观察,结果表明,磁电阻MR随Fe含量而变化,而体积分数为47％时获得最大值4．0％,45％Fe-Al2O3颗 膜的室温磁性表现为超顺磁性,磁电阻MR与－（M／Ms)2成正比,相关常数A约0．036,HRTEM观察表明,当Fe颗粒尺寸约小于1nm时,Fe颗粒为非晶态,而大于该尺寸时则为晶态,在Fe-Al2O3颗粒膜体系中存在与隧道相关的GMR,GMR的起因可归于传输电子的自旋相关的散射。     

化学组成对CoAlO颗粒膜隧道磁电阻效应的影响

采用热压工艺制备-系列CoAlO的靶材，在Gatan682型PECS＋RIBE系统上，于25℃下Ar气氛中沉积到Si（100）衬底基片上，得到颗粒膜．测量了电阻和磁电阻性质，用透射电子显微镜测量样品的面内晶粒尺寸CoAlO薄膜的化学组成，用x射线光电子能谱仪测量．研究了化学组成对CoAlO颗粒膜隧道磁电阻效应的影响．结果表明，得到的颗粒膜是由2～3nm的C0氧化物分布在AlOx母相中，在室温下可显示磁性，通过ALOx阻挡层具有比较大的隧道磁电阻效应（达-6％）；随温度升高，化学组成对隧道磁电阻影响更大．     

Zn0.5Fe2.5O4-(α-Fe2O3)多晶隧道结磁致电阻材料合成与制备

以PVA为分散介质,通过低温固相反应合成了组成结构均匀的单相超微Zn0.5Fe2.5O4颗粒,然后经成型、高温气氛控制反应烧结成功制备得到具有Zn0.5Fe2.5O4-（α-Fe2O3）双相微结构的多晶隧道结磁致电阻材料.利用DAT/TG、IR、XRD、SEM和VSM-4探针磁电阻测定等技术,就超微Zn0.5Fe2.5O4颗粒的合成和Zn0.5Fe2.5O4-（α-Fe2O3）多晶隧道结磁致电阻材料的微结构特征及其磁致电阻效应进行了初步测定和分析讨论.研究发现,不同溶液动力学条件下合成粉体的粒径明显不同,且在烧结过程中一定氧分压的存在有利于绝缘层的形成.     

巨磁电阻效应

重点综述了磁性多层膜、颗粒膜、钙钛矿型氧化物及铁磁薄膜隧道结等几种不同结构类型的巨磁电阻效应的研究现状及其进展情况,并简述了巨磁电阻的物理机制及磁传感器、随机存储器和高密度读出头等几方面的应用,还涉及到了制备这些巨磁电阻材料的常用方法,并列举了10种不同组分的巨磁电阻材料,还说明了特大磁电阻和巨磁电阻的不同。     

Cu层厚度对NiFe/Cu/Co 的巨磁电阻效应影响

用磁控射频溅射法制备了NiFe/Cu/Co多层膜;研究了薄膜的磁特性和磁电阻特性与中间层Cu厚度的关系.在适当的Cu层厚度下 (大约为2 nm),制备出了具有很好自旋阀巨磁阻效应的多层膜.研究表明,在弱磁场下,薄膜的磁电阻回线的斜率与原来的磁化过程有关,因此该薄膜材料可以用于巨磁电阻存储器中.     

NiCo-Ag纳米颗粒膜输运性质的研究

采用离子束溅射技术制备了一系列不同含量x的(Ni0.8Co0．2)x-Ag1-x。颗粒膜样品，并对样品的各向异性磁电阻和巨磁电阻效应进行了研究，在x=0．4的样品中，GMR值达最大值，为-3％，而AMR值在x=0．75时为0．8％。随着NiCo质量分数x的增加，电子输运行为有着一个从GMRAMR的转变。考察其输运性质，试图来更深入地理解各向异性磁电阻和巨磁电阻效应的物理本质。     

Co/Cu/Co结构中纳米氮化物界面掺杂研究

研究了纳米氮化物(NNL)界面掺杂对Co/Cu/Co磁电阻的影响.当NNL在下界面(Co/Cu)掺杂时,得到了反常磁电阻为-0.043%;当NNL在上界面(Cu/Co)掺杂时,磁电阻近似为0;当NNL同时在上、下界面掺杂时,得到的反常磁电阻为-0.005%.运用Camley-Barnas的玻尔兹曼半经典理论模型,通过调整界面参数计算其磁电阻,发现改变界面自旋相关散射系数能对实验结果给出合理解释,证明了NNL掺杂确实能改变界面自旋相关散射系数.     

颗粒间隧穿体系H-A模型的磁电阻翻转效应

基于HELMAN-ABELES模型,超越传统的一级近似,对磁场相关库仑阻塞下体系的磁输运性质进行了系统的理论分析.我们发现,磁场相关的库仑能隙将引起低温下的正磁电阻发散行为,该行为与自旋极化引起的低温负磁电阻相互竞争,使体系的宏观磁电阻随参数的区域变化呈现出复杂的特征.我们分析了该正磁电阻出现的根本原因,从而指出影响磁电阻的因素除了传统的自旋极化率之外,还有与之效果相反的自旋相关库仑能隙的作用,后者为颗粒体系中的磁电阻效应提供了新的可能来源.     

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.