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1.
提出了一种基于13.56MHz激发的微感应耦合等离子体射流源,含碳的等离子体射流在绕有水冷线圈的石英管中产生.激光拉曼光谱及紫外-可见光谱分别用以研究基片负偏压对所生长的非晶碳膜结构特征的影响.结果表明:碳基微等离子体射流具有很强的活性,碳膜的生长速率高达0.8μm/min,但随着衬底负偏压的增加而降低;Raman光谱显示在1350cm^-1、1580cm^-1附近存在D峰、G峰,是典型的类金刚石碳膜;薄膜中碳主要以sp^2、sp^3碳及无序的聚合碳链形式存在,随偏压的增加,薄膜中聚物碳链结构被打断,分解形成sp^2、sp^3碳杂化态,Raman荧光本底减弱,sp^2和sp^3的含量之比增加,光学带隙呈现降低趋势.  相似文献   

2.
介绍了在KOH固体及相转移催化剂参与下,二氟二氯甲烷(F12)与乙腈发生一种新颖的碳化反应,生成棕色的富碳材料.这种碳材料在700℃下加热分解提纯后得到直径在30~80nm的多孔碳粒子.其结构中同时含有sp、sp2与sp3杂化的碳原子.  相似文献   

3.
金刚石是一种集多种优良性能于一体的功能材料,但是,金刚石薄膜sp^3碳构造的高稳定性导致其表面活性不足,无法满足各种功能性表面的需要.本文从化学修饰角度,研究了卤素在金刚石薄膜表面导入的方法和修饰后的应用,并对修饰后的金刚石表面进行了XPS表征.结果表明,卤素已成功的修饰到了金刚石薄膜表面.  相似文献   

4.
采用空心阴极等离子体化学气相沉积法,在甲烷一氨气、氢气混合气体体系下,制备出了非晶碳氮薄膜。利用原子力显微镜(AFM)及X射线光电子能谱(XPS)对薄膜的表面形貌、成分及微观结构进行了测试和表征。结果表明,薄膜的表面光滑、致密,均方根粗糙度小于0.5nm;薄膜中的氮含量随NH3(H2)流速的增加呈现降低的趋势,sp^2C—N及sp^3C—N键含量均随氮含量的增加而增加。  相似文献   

5.
在15 kW加压流化床富氧燃烧实验台上,进行了内蒙古烟煤在850~900℃下的加压富氧燃烧实验,研究了压力为0. 1~0. 4 MPa、空气和21%~30%氧浓度的O_2/CO_2气氛下燃烧的碳转化规律.研究结果表明:稳态富氧燃烧条件下,加压流化床富氧燃烧实验台干烟气中CO_2浓度均超过90%.提高燃烧压力有利于提高碳转化率和CO_2生成率,有利于降低CO生成率.在压力0. 1~0. 3 M Pa范围内,CO_2生成率随着压力的增加基本呈线性递增关系,从85%左右增加到93%左右.进一步增加压力,CO_2生成率逐渐趋于平稳,并保持在较高水平.在压力为0. 4 MPa条件下,CO_2生成率增加到95%左右.提高O_2/CO_2气氛的氧浓度能够提高碳转化率和CO_2生成率,但是随着压力的提高,氧浓度对碳转化率和CO_2生成率的影响减小.  相似文献   

6.
采用脉冲激光沉积方法,通过改变脉冲激光能量在单晶硅衬底上制备了类金刚石薄膜,利用椭圆偏振光谱和拉曼光谱对得到的薄膜进行测试,并对沉积过程中的碳等离子体发射光谱进行了研究。薄膜测试结果表明,随着脉冲激光能量的增大,薄膜sp^3成分增多。沉积过程中的碳等离子体发射光谱原位监测表明,随着脉冲激光能量的增大,C、C^+、C^2+粒子发射光谱强度增强,根据应力模型薄膜sp^3成分增多,与薄膜测试结果一致。并且发现C^+粒子在形成sp^3键过程中起到了非常重要的作用。  相似文献   

7.
使用脉冲激光沉积(PLD)技术制备了系列无氢类金刚石(DLC)薄膜,测量了样品的Raman光谱、光吸收和光致发光,研究了光致发光与制备条件的依赖关系。结果表明,这种薄膜是有少量sp^2键和sp^2键组成的非晶碳膜。薄膜的光学带隙在1.68~2.46eV,发光在可见光区呈宽带结构。沉积温度对类金刚石薄膜的结构和发光性质有较大影响。当沉积温度从室温升高至400℃时,sp^2团簇的长大使C原子的有序度增强,从而导致薄膜的光学带隙变窄,发光峰红移且半高宽变小。  相似文献   

8.
润滑油摩擦碳化产物的FT-IR及Raman评价   总被引:5,自引:0,他引:5  
为了解全配方合成润滑油(SJ/CF/5W-30)在摩擦磨损期间的碳化解聚过程及特点,分别采用反射红外(FT-IR)和激光拉曼(laser-Raman)分子谱仪对摩擦副的磨损表面进行分析。结果表明:润滑油的碳化解聚随着温度的升高逐步进行。在足够高的温度下,润滑油可完全碳化解聚成与原物质完全不同的富碳物质。该富碳物质包括无序碳(D线峰)与有序碳(G线峰)两种类型,具有典型的碳质材料特征。这两种类型的碳的峰位、峰宽等参量以及所形成的石墨微晶大小均与温度有关。  相似文献   

9.
目的研究合成有机导体“桥式”四硫富瓦烯衍生物的方法。方法以6,7-二(2'-氰乙硫基)-2,3-二甲硫基四硫富瓦烯为原料,在醇钠的作用下分两次消去氰乙基生成硫负离子。第一次生成的硫负离子与对二氯甲苯反应生成一种新的“一桥”-双四硫富瓦烯衍生物,该衍生物再分别与醇钠和对二氯甲苯反应生成另一种新的“二桥”-双四硫富瓦烯衍生物。结果“一桥”和“二桥”- 双(四硫富瓦烯衍生物)有特殊的电化学性质和很强的紫外吸收。结论为“桥式”四硫富瓦烯衍生物的合成提出了一种新方法。  相似文献   

10.
柴油-甲醇组合燃烧碳烟排放模型   总被引:2,自引:0,他引:2  
采用柴油-甲醇组合燃烧模式可以大幅度降低柴油机碳烟排放.由于组合燃烧模式碳烟排放机理与传统柴油机不同,因此对采用组合燃烧的柴油机进行性能预测,需要建立新的碳烟排放模型.在试验研究的基础上对广安博之的两步碳烟排放模型进行修正,提出了一个新的碳烟生成模型.该模型考虑到了甲醇对碳烟生成的影响.模拟结果与试验结果对比分析表明,该模型计算结果与实测结果一致性良好,能够用来预测柴油一甲醇组合燃烧发动机的碳烟排放.  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
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.  相似文献   

15.
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。  相似文献   

16.
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.  相似文献   

17.
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-  相似文献   

18.
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-  相似文献   

19.
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  相似文献   

20.
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  相似文献   

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