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1.
采用直流反应磁控溅射法在玻璃衬底上制备了Sn掺杂ZnO透明导电薄膜,用Hall效应测试仪表征了薄膜的电学性能,研究了不同生长条件对薄膜电学性能的影响。研究结果表明,随着Ar/O2比的增加,电阻率先减小后增大,在Ar/O2为6时,取得最低的电阻率为2.02×10-2Ω·cm;随着溅射功率的增大,薄膜电阻率急剧减小,在140 W时获得最低电阻率为2.89×10-2Ω·cm;在溅射时间11min时得到了最低的薄膜电阻率,为1.45×10-2Ω·cm。随着压强的增大,电阻率先急剧减小,后缓慢增大,当溅射压强为0.8Pa时,薄膜电阻率具有最小值,为2.17×10-2Ω·cm。当衬底温度在400~500℃范围内变化时,在475℃时取得最佳电学性能,电阻率为2.26×10-2Ω·cm。在整个实验条件下,当Ar/O2为8、溅射功率为180W、衬底温度为450℃、溅射压强为0.5Pa、溅射时间为11min时,薄膜具有最佳的导电性能,电阻率为1.45×10-2Ω·cm。  相似文献   

2.
ATO包覆型导电纤维的制备   总被引:2,自引:0,他引:2  
以莫来石纤维为基体,采用共沉淀法在其表面沉积一层锑掺杂氧化锡(ATO),制得导电纤维,并研究了制备工艺对导电纤维电阻率和颜色的影响.结果表明:热处理温度为600~1 000℃时制备的导电纤维的电阻率低于50Ω.cm,与同条件下制备的ATO的电阻率相差不大;热处理温度为1 000℃以上时,由于莫来石纤维中的部分A l3 进入氧化锡晶格出现补偿效应,致使导电纤维的电阻率急剧下降;导电纤维的亮度L*大于同温度下制备的ATO的亮度,而且差值都在10个单位以上;导电纤维与硫酸钡标准样品的色差ΔE小于10个NBS.  相似文献   

3.
环氧树脂/石墨微片复合导电材料的导电性   总被引:3,自引:0,他引:3  
研究环氧树脂 /石墨微片复合导电材料的制备规律 ,实验发现固化剂种类、固化剂用量和固化条件对复合材料的电阻率都有影响 不同的固化剂 ,复合材料的电阻率不同 ,在最佳固化剂用量和最佳固化条件下 ,复合材料可获得最低电阻率 实验还研究石墨含量对环氧树脂复合导电材料的影响 ,发现复合材料具有渗滤效应 ,渗滤区石墨质量分数为 0 .0 2~ 0 .0 5 ,相应的电阻率约为 10 12 ~ 10 4Ω·cm .  相似文献   

4.
采用辅助超声方法较好地解决了埋栅硅太阳电池化学镀铜经常发生槽内空洞和镀不满的现象,使电池串联电阻由0.5Ω降为0.1Ω.在化学镀银过程中,采用聚四氟乙烯材料作容器,避免了银沉积容器内壁.镀液中加入络合剂-氨水,可较好地控制反应,使镀银效果大大提高.  相似文献   

5.
片状银粉形成导电通道时颗粒间是线接触或面接触,因而具有良好的导电性而被广泛用作导电胶的填料.通过对微米银片的表面处理能够改善导电胶的导电性能和连接性能.采用有机二元酸处理过的微米银片制备的导电胶与未处理微米银片制备的导电胶相比,导电性能可提高4~6倍;戊二酸处理的微米银片制备的填充量为80%的导电胶的电阻值可达到4.0×10-5Ω.cm,连接强度为4.2×106Pa;电镜、Raman光谱和热分析结果表明,戊二酸与银表面发生了化学吸附,其吸附量约为1.4%.  相似文献   

6.
 采用化学镀法在聚酯纤维表面镀覆一层导电银层,采用场发射扫描电镜(FE-SEM)、电子能谱仪(EDS)、X射线衍射仪(XRD)分别对聚酯纤维镀银前后的表面形貌、化学元素组成、银结晶结构进行表征.讨论了乙二胺浓度、AgNO3浓度、施镀时间和镀液温度对化学镀银聚酯纤维增重率及电阻率的影响,测试化学银镀层与纤维基体的结合牢度和耐腐蚀性.结果表明,最佳工艺条件下,电阻率低至2.31Ω·cm-1;镀层为高纯度的面心立方结构的单质银;银镀层具有良好的与基体的粘结强度和耐化学腐蚀性能.
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7.
利用自由基辅助磁控溅射法在载玻片衬底上制备了透明导电ZnO:Al薄膜(简称AZO薄膜).研究了氢气气氛中后续退火处理对Al掺杂效率以及AZO薄膜性能的影响.研究结果表明,退火处理提高Al的掺杂效率、降低中性杂质浓度,从而提高了AZO薄膜的导电性能.AZO薄膜550℃下在H2气氛中退火处理后,其电阻率为6.5×10-4Ω·cm,550nm波长的透射率为85.7%,载流子浓度为3.3×1020cm-3,迁移率为29.7cm2·V-1·s-1.  相似文献   

8.
常压固相烧结法制备ZAO靶材及其性能的研究   总被引:3,自引:0,他引:3  
采用常压固相烧结法,通过优化烧结工艺,制备出平整、组织均匀、致密的ZAO靶材.研究了掺杂含量、烧结温度对陶瓷靶材微观结构和性能的影响,并使用自制靶材,采用射频磁控溅射法镀膜.结果表明:Al2O3的掺杂没有破坏ZnO晶体结构,Al原子对Zn原子进行有效替位;晶粒尺寸随着掺杂量的增多而减小;靶材的电阻率随掺杂量的增加呈U型变化,在3wt%时取得最小值4.2×10-2Ω.cm;靶材致密度超过96%.使用该靶材生长的多晶ZAO薄膜具有(002)择优取向,结晶均匀,呈柱状生长,薄膜电阻率和可见光平均透射率可分别达到8×10-4Ω.cm~9×10-4Ω.cm和85%.图9,表1,参14.  相似文献   

9.
采用射频磁控溅射方法,用Ga2O3含量为1%的ZnO做靶材,在不同基体温度和不同溅射压强的条件下制备了高质量的GZO透明导电薄膜.结果表明:基体温度和氩气压强对GZO薄膜的晶体结构、光电性能有较大影响.当温度为500℃,溅射气压为0.2Pa时制备的GZO薄膜光电性能较优,方块电阻为7.8Ω/□,电阻率为8.58×10-4Ω.cm,可见光的平均透过率为89.1%.  相似文献   

10.
室温下采用直流磁控溅射法在PI衬底上制备出具有优异光学性能的ZnO∶Ga透明导电薄膜.研究结果表明,制备了具有C轴择优取向的六角纤锌矿结构的多晶GZO透明导电薄膜.讨论了薄膜厚度对PI衬底上制备ZnO∶Ga薄膜的结构、表面形貌和电学性质的影响.实验数据表明,一定同质缓冲层可有效降低薄膜应力,改善薄膜性能,所得GZO薄膜厚度为129nm时,电阻率具有最小值3.2×10-4Ω.cm.  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.
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   

17.
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   

18.
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   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
1 Rise of studies on climate change's effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America's annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].  相似文献   

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