温度对量子点接触电导量子化的影响

利用简单的２Ｄ－准１Ｄ－２Ｄ（二维－准一维－二维）理论模型，研究了零温和有限温度下，介观尺寸量子点接触中的电导随费米能的变化关系，计算表明，在较低温度下（如８Ｋ），温度效应使一定纵横比的量子点接触电导一台振荡消失，但电导仍２ｅ＾２／ｈ为单位的量子化。     

ZrO_2－Tb_2O_（3．5）－Y_2O_3氧化物体系的混合导电性和氧渗透

以电化学方法研究了ＺｒＯ２－Ｔｂ２Ｏ３．５－Ｙ２Ｏ３复合氧化物体系的混合电导和氧渗透性，并从固体缺陷化学的角度进行了讨论．结果表明，在所研究的组成范围内（Ｔｂ含量高达５０ｍｏｌ％），试样皆为面心立方萤石结构，其晶格常数随Ｔｂ含量增多而线性增大．Ｔｂ元素的变价及其随温度和组成的依赖关系决定了体系的混合电导性质．Ｔｂ含量的增多导致电子电导的增大，而Ｙ的掺入对其电性质的改善不明显．氧渗透性决定于材料电子电导和离子电导的综合作用，氧渗透通量较ＺｒＯ２－Ｙ２Ｏ３体系提高了１～２个量级．氧渗透过程机制遵循氧离子和电子空穴通过材料膜的体扩散为控制步骤这一模型．     

温度和量子线的纵横比对电导振荡现？…

利用两端区域为二维自由电子气，中间区域为准一维均匀值通道的简单理论模型，即２Ｄ－准１Ｄ－２Ｄ模型，了低温下不同纵横比（通道长宽比）的量子线电子弹道输运性质。理论计算结果表明，量子线弹道区电子输运性质与道纵横比和温度两者有密切关系，即随重整化标准费米能变化而产生的电导量子化和电导振荡现象强烈地依赖于温度和通道纵横比两者，而不仅仅依赖温度。     

流动注射化学发光法测定还原型辅酶Ⅰ

将还原型辅酶Ⅰ（ＮＡＤＨ）还原Ｆｅ３＋生成Ｆｅ２＋的化学反应与Ｆｅ２＋催化溶解氧氧化Ｌｕｍｉｎｏｌ的化学发光反应相偶合,同时采用试剂固定化技术将体系中的分析试剂Ｆｅ３＋及Ｌｕｍｉｎｏｌ全部电价固定在离子交换柱中,建立了一种测定还原型辅酶Ⅰ的流动注射化学发光新方法．该法对于ＮＡＤＨ响应的线性范围为１．０×１０－７～１．０×１０－４ｍｏｌ／Ｌ,检出限为５．５×１０－８ｍｏｌ／Ｌ,相对标准偏差小于５％（１．０×１０－７ｍｏｌ／Ｌ,ｎ＝７）．     

氨合成铁催化剂上化学吸附物种的in－situ FTIR谱

应用原位傅里哀变换红外光谱方法，分别在４００～４５０℃、常压、高空速（１２０００～１４４００ｈ．ｓ．ｖ．ｇ．）的Ｈ２、Ｎ２／３Ｈ２或Ｎ２气氛的动态条件下，检测了双促进氨合成铁催化剂上的化学吸附物种，并分别在Ｄ２、Ｎ２／３Ｄ２或１５ＮＨ３／Ｈ２气氛中，进行了常规同位素验证实验．结果表明，催化剂表面的主要含氮化学吸附物种是分子态的Ｎ２．ａｄ，其ｕ（Ｎ－Ｎ）＝２０３６ｃｍ－１（ｓ），２０１２ｃｍ－１（ｗ）和１９３５ｃｍ－１（ｗ），而不是原子态的Ｎａｄ，其ｕ（Ｆｅ－Ｎ）＝１０８７ｃｍ－１（ｖｗ），和ＮＨａｄ其ｕ（Ｆｅ－Ｎ）＝８８６ｃｍ－１（ｖｗ），表面有相当量的化学吸附氢存在，其ｖ（Ｆｅ－Ｈ）＝２０５６ｃｍ－１（ｓ），１９５０ｃｍ－１（ｍｓ），１９３１ｃｍ－１（ｍ），１９０２ｃｍ－１（ｗ），９１５ｃｍ－１（ｓ，桥式）等．作为与报道过的激光拉曼光谱的互补研究，本结果支持了以缔合式途径为主、解离式途径为次的平行竞争缔合式合成氨催化反应机理．     

纺锤型γ－FeOOH的合成及其热分析研究

采用空气氧化ＦｅＳＯ４与Ｎａ２ＣＯ３作用生成的Ｆｅ（ＣＯ３）ｘ（ＯＨ）２（１－ｘ）悬浮液体系，通过稀土离子Ｙ３＋的掺杂合成出均匀纺锤型铁黄γ－ＦｅＯＯＨ微晶．由ＤＴＡ－ＴＧ和ＸＲＤ分析得出γ－ＦｅＯＯＨ随温度升高，发生如下相变过程：γ－ＦｅＯＯＨ→γ－Ｆｅ２Ｏ３→α－Ｆｅ２Ｏ３．本文还对γ－ＦｅＯＯＨ的脱水过程机制和以γ－ＦｅＯＯＨ为中间体经热处理制备的纺锤形γ－Ｆｅ２Ｏ３磁性能作了初步探讨．     

氯化乙基铝／给电子体催化烯烃齐聚

研究了氯化乙基铝／给电子体组成的新的烯烃齐聚催化体系。在甲苯溶剂中，以 Ｅｔ_３Ａｌ_２Ｃｌ_３／ＰＰｈ_３为催化剂，在Ａｌ／Ｐ为 ８，反应温度为 ８０℃，反应时间为２ｈ 条件下，丙烯齐聚转化率为４９．５％，二聚选择性为９１．３％；催化１－丁烯齐聚反 应，丁烯转化率仅为３．５％；而在临氢条件下催化１－丁烯齐聚反应，可以大幅度提 高１－丁烯的齐聚转化率。使用本催化体系所得丙烯、１－丁烯的二聚物都是具有支链 结构为主的烯烃。对反应条件的影响及氯化乙基铝／给电子体两组分的催化作用进行 了探讨，认为属铝氢化物反应机理。     

镍电解液萃取净化研究-用二(2.6-二甲基-4-庚基)磷酸萃取净化流程的数学模型及最优化计算

本文提出用二（２．６－二甲基－４－庚基）磷酸［ＨＤ（ＤＩＢＭ）Ｐ］作为萃取剂，用于镍阳极电解液中的Ｎｉ２＋、Ｃｏ２＋、Ｃｕ２＋和Ｆｅ３＋的萃取分离流程。在一定的工艺条件下，测定了各种金属离子的平衡数据，建立了Ｎｉ２＋、Ｃｏ２＋、Ｃｕ２＋和Ｆｅ３＋的分配模型。并在此基础上，针对含有 １４０ 克／升 ＳＯ４－２和 ４０克／升 Ｃｌ－的镍阳极电解液体系对其中 Ｎｉ２＋、Ｃｏ２＋、Ｃｕ２＋分离工艺进行了最优计算，并确定了水法处理该溶液的萃取流程。所得最优工艺参数为：温度＝５０℃；ＨＤ（ＤＩＢＭ）Ｐ浓度＝０．２３Ｍ； ｐＨ＝５，７４； ３级，有机相对于水相流比Ｏ／Ａ＝０．３１。此时，镍回收率为９９％，钴回收率为９４．１％，铜回收率为９９．９９％。此项研究由北京第五研究所提供萃取剂。     

金属-氨基多羧酸类配合物分子和晶体结构的研究(Ⅲ)——K〔Fe~Ⅲ(ida)_2〕·3H_2O配合物的合成及结构测定

本文报导了Ｋ〔ＦｅⅢ（ｉｄａ）２〕·３Ｈ２Ｏ（ｉｄａ２－＝氨基二乙酸根）配合物的合成及它的分子结构和晶体结构的测定．具体结果如下：正交晶系，Ｐｂｃｎ空间群，ａ＝１８．７６５（３），ｂ＝１０．４４７（３），ｃ＝１５．６４５（２），ｖ＝３０６７（１）３，单位晶胞中的分子数为８，Ｄｃ＝１．７８ｇ·ｃｍ－３，Ｄｏ＝１．７２ｇ·ｃｍ－３，μ＝１．３１４ｍｍ－１，Ｆ（０００）＝１６８８，对于２７６７个独立的衍射点，它的Ｒ和Ｒｗ值分别为０．０５２和０．０４７．其中〔ＦⅢ（ｉｄａ）２〕－是一个Ｎ和Ｎ顺位的近似八面体结构．由此可知具有对称电子结构（ｈｉｇｈ－ｓｐｉｎｄ５）的ＦｅⅢ与被看成是ｅｄｔａ４－（＝乙二胺四乙酸根）去掉了ＣＨ２—ＣＨ２基团的双ｉｄａ２－配体形成的配合物只能选择六配位的八面体结构     

（C6Me6）2Fe.PCNP2类化合物的导电模型

用ＣＮＤＯ／２Ｍ方法计算了（Ｃ６Ｍｅ６）２Ｆｅ．ＰＣＮＰ２和（１，３，５－Ｍｅ３Ｃ６Ｈ３）２Ｆｅ．ＰＣＮＰ２有机导体分子的电荷密度、键级等量子化学参数。计算表明，（Ｃ６Ｍｅ６）２Ｆｅ．ＰＣＮＰ２分子中两个苯环骨架Ｃ原子和Ｆｅ所带的电荷密度分别大于（１，３，５－Ｍｅ３Ｃ６Ｈ３）２Ｆｅ．ＰＣＮＰ２分子的。     

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.     

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.     

A computer generator for randomly layered structures

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

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the