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1.
a-C:H膜及其退火的激光喇曼光谱研究   总被引:1,自引:0,他引:1  
用高频阴极辉光放电沉积在控制基片温度来制备氢化非晶态碳(a—C:H)膜,退火温度上升到600℃,这些膜的喇曼光谱在波区1000~1800cm~(-1)进行的,a-C:H膜的喇曼光谱是一个非对称的简单的谱带。随着退火温度的升高,a—C:H膜出现两个峰值,也观察了金刚石和天然石墨的喇曼光谱,这些光谱与现代研究的模型进行了讨论,其结果认为非晶态碳具有三次配位和四次配位原子的网状结构模型相一致。  相似文献   

2.
将氢化非晶碳薄膜(GDα-C:H)应用于硅半导体晶体管的表面钝化,取得了与α-Si:H 膜相类似的效果。对α-C:H 的钝化机理进行了初步探讨。  相似文献   

3.
采用外耦合电容式射频辉光放电等离子体 CVD 系统,在低于300℃的衬底温度下,制备出了 a—Si(1-x)C_x∶H 钝化膜.对含碳量不同的3种样品作了热稳定性实验(即高温存放、温度循环和退火).另外,还对同一号样品做了在不同温度下退火30min 的实验.结果表明,此钝化膜的释氢温度高于600℃.具有很好的热稳定性.  相似文献   

4.
研究了不同衬底温度,不同掺钇浓度的a-Si:H(Y)膜的红外吸收谱,并与未掺杂的a-Si:H 膜比较。利用吸收峰的积分估算了样品中Si-H 键的数目。  相似文献   

5.
采用直流磁控溅射方法,以Ar/N2为放电气体(N2/(Ar N2)=10%),在玻璃和NaCl(100)单晶片上分别沉积获得Fe-N薄膜样品.利用X射线衍射(XRD)、原子力显微镜(AFM)和超导量子干涉仪(SQUID)对样品的结构、形貌和磁性能进行分析,研究基片和基片温度等条件对薄膜的影响.结果表明,以NaCl单晶为基片获得单相γ′-Fe4N薄膜,与玻璃基片相比可降低其生成的基片温度并可扩大形成温度的范围,且比饱和磁化强度略有增大.  相似文献   

6.
采用磁控溅射法,在玻璃基片上制备了一系列不同Ni79Fe21含量的(Ni79Fe21)x-(Al2O3)1-x纳米颗粒膜样品,并对样品的巨霍尔效应进行了研究.在(Ni79Fe21)0.48-(Al2O3)0.52颗粒膜样品中,透射电镜(TEM)照片清晰地显示出纳米Ni79Fe21颗粒包裹于Al2O3中,且电子间的量子相干效应明显,这可能是导致霍尔效应增强的主要原因.室温下测出了最大的巨霍尔效应值达到4.5 μΩ*cm.改变基片温度,发现巨霍尔效应值变化不大,说明该颗粒膜具有良好的热稳定性,因而在磁传感器上有良好的应用前景.  相似文献   

7.
在玻璃基片上直流磁控溅射沉积氧化铋薄膜,基片温度从室温增加到300℃并保持其它沉积条件一致,研究基片温度对薄膜光学性能的影响.样品的晶体结构、表面形貌和透射光谱分别用X射线衍射仪、原子力显微镜和分光光度计进行测量.结果表明,随着基片温度的增加,样品中Bi2O3的(120)衍射峰强度增强,表面颗粒直径逐渐减小;基片温度为...  相似文献   

8.
La_(0.67)Sr_(0.33)MnO_3薄膜的外延性及其巨磁电阻效应   总被引:1,自引:0,他引:1  
利用直流溅射法在(001)LaAIO_3基片上生长了外延的La_(I--x)Sr_xMnO_3(x=0.33)薄膜,薄膜为立方晶系的钙钛矿氧化物,晶格常数为a=39.2nm测量了薄膜在零场和外加场中的电阻率和磁阻随温度的变化。随着基片温度的升高。磁阻值在减少;电阻率峰位向高温区移动;溅射温度为650℃的样品磁阻效应最大,磁电阻效应约达30%。  相似文献   

9.
采用磁控溅射法 ,在玻璃基片上制备了一系列不同Ni79Fe2 1含量的 (Ni79Fe2 1) x (Al2 O3 ) 1-x纳米颗粒膜样品 ,并对样品的巨霍尔效应进行了研究。在 (Ni79Fe2 1) 0 .48 (Al2 O3 ) 0 .52 颗粒膜样品中 ,透射电镜 (TEM )照片清晰地显示出纳米Ni79Fe2 1颗粒包裹于Al2 O3 中 ,且电子间的量子相干效应明显 ,这可能是导致霍尔效应增强的主要原因。室温下测出了最大的巨霍尔效应值达到 4 .5 μΩ·cm。改变基片温度 ,发现巨霍尔效应值变化不大 ,说明该颗粒膜具有良好的热稳定性 ,因而在磁传感器上有良好的应用前景  相似文献   

10.
用电子回旋共振等离子体化学气相沉积(ECR-CVD)方法在不同基片温度下从苯制得了含氢非晶碳膜(a-C:H),对样品进行了伏安特性测试,考察了基片温度对电阻率与击穿场强的影响,并结合Raman谱探索a-C:H膜的导电机制。  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.
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.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
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   

15.
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   

16.
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。  相似文献   

17.
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.  相似文献   

18.
19.
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  相似文献   

20.
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  相似文献   

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