射频溅射金属前驱体硫化法制备的Cu_2ZnSnS_4薄膜(英文)

采用射频溅射技术沉积Cu/Sn/Zn金属前驱体叠层结合硫化技术在玻璃衬底上成功制备了Cu2ZnSnS4薄膜。X-射线衍射分析表明,通过优化制备条件可以获得单一黝锡矿结构且具有(221)择优取向的Cu2ZnSnS4薄膜。霍尔效应和紫外可见透过谱测量表明,样品的薄膜电阻、吸收系数和光学带隙分别达到0.073Ω.cm,104cm-1和1.53eV,具有适合作为薄膜太阳电池吸收层应用的可能性。     

溶胶—凝胶法制备Cu2ZnSnS4薄膜及其表征

采用溶胶—凝胶法和旋涂技术在FTO玻璃衬底上制备了Cu2ZnSnS4(CZTS)前驱体薄膜,在氩气氛围中退火后获得Cu2ZnSnS4薄膜.利用X射线衍射仪(XRD)、拉曼光谱仪(Raman)、扫描电子显微镜(SEM)、紫外—可见分光光度计(UV-VIS)对样品进行表征分析结果表明:450℃退火后的样品为纯相的Cu2ZnSnS4,样品的晶粒尺寸较大,禁带宽度接近太阳光谱的禁带宽度.     

CZTS薄膜制备的研究进展

Cu2ZnSnS4(CZTS)具有与太阳光谱非常匹配的禁带宽度以及高的吸收系数,这使得CZTS薄膜成为一种最具潜力的新型太阳能电池薄膜吸收层材料。因此研究和完善CZTS薄膜的制备技术并提高薄膜质量及性能成为重要的研究课题。本文主要介绍四种CZTS薄膜的制备方法:磁控溅射、共蒸发、混合溅射、电子束蒸发硫化法。     

Cu_2O透明导电薄膜的制备技术及应用

氧化亚铜(Cu2O)具有优越的光电性质,是一种具有广泛用途的材料。本文概述了国内外氧化亚铜(Cu2O)透明导电薄膜的多种制备技术;详细介绍了磁控溅射、电化学沉积、热氧化法等工艺在Cu2O薄膜制备中的研究现状,及其在太阳能电池上的应用;对比了不同工艺条件下Cu2O薄膜的性能,并指出制备Cu2O薄膜中的一些问题。     

替代元素对光催化半导体Cu2ZnSnS4能带结构优化的第一性原理研究

【目的】为了增加Cu2ZnSnS4价带顶和导带底与水的氧化还原势之间的能量差,使催化反应具有更多的驱动力。【方法】利用第一性原理计算,对Cu2ZnSnS4电子结构进行分析。【结果】Ag掺入Cu位能够降低其价带顶而不改变导带底位置,而Ge掺入Sn位能够提升其导带底而不改变价带顶位置。【结论】通过优化(Cu1-xAgx)2Zn(Sn1-yGey)S4合金的配比,可使其达到光催化半导体最理想的能带结构。     

电化学沉积CaWO4薄膜及表征

在室温条件下，采用恒电流电化学沉积技术直接在钨片基体上制备了白钨矿结构的CaWCId晶态薄膜。电化学反应的工艺参数为：电流密度为1mA／cm^2、电解液的pH值为13．0、电化学处理时间为1．5h。采用XP,D、XPS、SEM技术分析了制备的CAWO4薄膜的晶相、化学组成和表面形貌，所制备的薄膜是表面均匀致密的四方晶系的单相薄膜。     

La0．67Ca0．33MnO3／YBa2Cu4O8／La0．67Ca0．33MnO3三效应研究层膜的时间

报导了La0．67Ca0．33MnO3／YBa2Cu4O8／La0．67Ca0．33MnO3薄膜中超导特性的时间效应。样品在空气中存放11个月后，超导转变温度都降低，而且每个系列样品的临界厚度增加。对用La0．67Ca0．33MnO3作保护层的YBa2Cu4O8薄膜进行时间效应测量，结果表明当La0．67Ca0．33MnO3层的厚度大于40nm时可以防止水对YBa2Cu4O8薄膜的影响。     

钙钛矿La2/3Ca1/3MnO3/YBa2Cu4O8/La2/3Ca1/3MnO3三层薄膜的磁输运性能

高温超导材料YBa2Cu4O8(YBCO)和铁磁材料La2／3Ca1／3MnO3(LCMO)形成的三层薄膜LCMO／YBCO／LCMO由对靶溅射技术制得．与YBCO单层薄膜相比，由于超导／铁磁系统中的磁性邻近效应，三层薄膜表现出较低的超导转变温度(Tc,ON)．与LCMO单层膜相比，三层薄膜的金属半导体转变温度(TMS)被提高并且强烈依赖于YBCO层的厚度．随中间层厚度的变化，磁电阻显示出非单调行为，长振荡周期被发现．结果表明，当YBCO处于正常态时两层LCMO膜之间存左着磁性自旋相互作用．     

化学浴沉积法制备纳米氧化亚铜薄膜

用改进后的化学浴沉积法制备了纳米Cu2O薄膜,并对成膜条件及膜的性能进行了研究．结果表明：化学浴沉积法改进后有利于制备高质量的纳米Cu2O薄膜;最佳反应温度为60～70C,此温度范围内Cu2O薄膜的膜厚随着循环次数线性增加．制备的薄膜纯度较高．表面较平整和致密,Cu2O粒径为14～22nm,其禁带宽度为2．01eV．     

铜溅射时间对Cu_2ZnSnS_4薄膜性能的影响

采用磁控溅射方法制备铜溅射时间分别为1.5 h和2 h的Cu/Sn/ZnS前驱体薄膜,然后利用双温区高温管式炉对两种薄膜进行硫化处理制备Cu_2ZnSnS_4.利用X射线衍射仪、拉曼光谱仪、扫描电子显微镜、能谱分析仪和紫外—可见分光光度计对薄膜的结构、表面形貌、化学成分和光学性能进行表征.结果表明:溅射1.5 h的Cu制备的薄膜表面存在大量杂质,表面很不平整;溅射2 h的Cu的薄膜表面呈现均匀致密的颗粒状薄膜,且具有更大的晶粒尺寸;溅射2 h的Cu的薄膜为单一CZTS相,其化学成分原子比更接近Cu_2ZnSnS_4化学计量比.     

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.     

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.     

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.     

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.     

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.     

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.     

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