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1.
二氧化锡超微粒子气敏薄膜的复数阻抗谱研究   总被引:1,自引:0,他引:1  
用直流气体放电活化反应蒸发法制备了二氧化锡超微粒子薄膜,测量了薄膜的阻抗谱,验证了超微粒子薄膜的内部模拟等效电路。研究了温度、还原性气体以及热处理对阻抗谱的影响,并用氧吸附理论和晶界热垒理论定性地解释了这些现象。  相似文献   

2.
采用热蒸发在载玻片和SiO_2衬底上沉积约5. 12 nm的Cu薄膜,再用退火炉分别进行100、200、300、400和500℃等5个温度退火,得到不同温度下的纳米Cu薄膜.用原子力显微镜和紫外-可见分光光度计研究不同退火温度对纳米Cu薄膜表面形貌、粒子分布和光学性质的影响.实验结果表明:当纳米Cu薄膜在载玻片上生长Cu颗粒阵列时,需要将退火温度控制在200℃左右;若使纳米Cu薄膜在SiO_2薄膜表面也能生长Cu颗粒阵列,退火温度比没有沉积SiO_2薄膜的衬底高100℃,此时纳米Cu颗粒对应方均根粗糙度为7. 20 nm、峰高(Skewness)为1. 75,以及偏态(Kurtosis)为5. 67,仅透射率略低9%.这样的Cu颗粒阵列更利于做超结构薄膜与完美吸收的顶层纳米金属颗粒.当退火温度为500℃时,载玻片上生长Cu薄膜的透射率出现一个相对稳定的波段,该工艺条件制备出来的纳米Cu薄膜,可以用来制作一些微型芯片,而SiO_2薄膜表面生长使纳米Cu薄膜对应方均根粗糙度为6. 25 nm、峰高为0. 57,以及偏态为2. 66.这样的Cu颗粒阵列不仅能够做大频率光电波吸收,还可以用作全固态电池中电解质上层的导电层.  相似文献   

3.
本文扼要报告了国内外目前制备超微粒子氧化铁的四条路线。考察了由Fe_2(SO_4)_3水溶液利用沉淀法制备α—FeO(OH)和α—Fe_2O_3的工艺过程。在沉淀反应温度40℃,晶型转化温度85℃和表面活性剂浓度为0.1mol/1时,可得到长轴为40—60nm,短轴10—15nm的纺锤状超微粒子氧化铁。  相似文献   

4.
以次磷酸钠(NaH_2 PO_2·H_2O)为还原剂,硫酸铜(CuSO_4·5H_2O)为前驱体,十六烷基三甲基溴化铵(CTAB)为表面活性剂,聚乙烯吡咯烷酮(PVP)为保护剂,在一缩二乙二醇(DEG)有机液相溶液中采用化学还原法成功地制备了铜纳米颗粒.采用XRD、TEM、SEM、纳米粒度仪及IR对所制备的铜纳米颗粒的结构、形貌、粒径大小及表面物质进行表征.结果表明制备的纳米铜粒子为球型颗粒,分散较好,尺寸较为均匀,平均粒径约为27 nm,并且具有立方晶型结构,其表面被有机物包覆.涂布纳米铜导电墨水的样品,其在高于250℃的温度下烧结60min后得到导电铜薄膜.温度在300℃烧结后,导电铜薄膜更加致密,可以推测铜薄膜的导电性能会增加.  相似文献   

5.
我们用离子团束-飞行时间质谱(ICB-TOFMS)系统制备了金(Au)超微粒子-聚乙烯(PE)薄膜和C60-聚乙烯薄膜。用透射电子显微镜(TEM)分析了所制备的样品。它们的结构是Au超微粒子镶嵌在多晶的PE薄膜中,其中Au原子团呈球形,直径分布在2.0-5.0nm窄范围内,当沉积基底温度为90℃时,Au原子团相互靠近,几乎连接起来,但仍保持原来大小。基底温度为140℃蒸积的C60-PE薄膜具有晶态  相似文献   

6.
RF磁控溅射法制备PbTe纳米薄膜   总被引:1,自引:0,他引:1  
利用RF磁控溅射和真空退火方法制备了PbTe纳米薄膜.利用SEM、XRD、AFM和FTIR分别对制备的样品的表面形貌和颗粒大小、结构以及带隙宽度进行了测试.结果显示,在10 W溅射功率下制备的PbTe纳米薄膜为纳米颗粒镶嵌薄膜,在20 W功率下为PbTe颗粒膜.10 W制备的纳米颗粒的平均直径为40 nm左右,平均高度为5 nm; 20 W制备的颗粒直径为100 -400 nm,平均高度为65 nm;两个条件下制备的样品均表现出明显的<100>方向的择优取向性,并且20 W的结晶质量比10 W的好.FTIR分析显示10 W和20 W制备的薄膜的带隙宽度分别为0.340 eV和0.343 eV,都比块体带隙宽度大.  相似文献   

7.
射频溅射功率和掺杂氢对硅氢薄膜结构的影响   总被引:1,自引:0,他引:1  
采用SEM和Raman谱对射频磁控溅射法制备的硅氢薄膜结构进行了研究,讨论了在100~400 W范围内溅射功率和氢气分压对硅氢薄膜结构的影响.结果表明,制备的硅氢薄膜为致密的颗粒膜,添加氢气后,颗粒状的硅氢薄膜出现了粒径更为细小的纳米级小颗粒亚结构;随着氢气分压的增加,其直径先增加后减小,平均直径在氢气分压为50%时达到最大;随着溅射功率的增加,硅氢薄膜的颗粒平均直径增加,当溅射功率达到400 W时,颗粒的平均直径为104 nm.拉曼光谱分析结果显示硅氢薄膜为非晶态.  相似文献   

8.
采用水热合成技术,使用硫酸钛和尿素直接在棉织物纤维表面包覆纳米TiO2颗粒薄膜.借助SEM、XRD、FT-IR、DSC和TG对棉纤维改性前、后的表面形貌、结构和热学性能进行了表征,并测定了织物反射光谱、拉伸、吸水和光催化活性.研究结果表明,棉织物经过硫酸钛尿素水热改性之后,纤维表面包覆了一层锐钛矿型纳米TiO2颗粒薄膜,由平均粒径2.0 nm的纳米颗粒聚集成100nm以上的球形颗粒,并通过物理吸附方式附着在纤维表面.改性后的织物热起始分解温度和吸热熔融峰温度均有所降低.具有抗紫外线能力和光催化活性,吸水性能也有所增强,但由于织物尺寸发生收缩,断裂强力有所减小,断裂伸长率有所增加.  相似文献   

9.
离子辅助反应蒸发技术室温制备ITO薄膜   总被引:2,自引:0,他引:2  
室温下利用离子辅助反应蒸发法在玻璃衬底上制备高透射比、低电阻率的ITO透明导电薄膜. 实验结果表明离子辅助蒸发可以有效地降低制备温度,提高薄膜的光电特性,薄膜具有明显的(222)择优取向,晶体粒子尺寸约为21 nm;离子源屏压、通氧量及沉积速率是影响薄膜光电特性的主要因素. 室温制备的ITO薄膜电阻率为2.4×10-3 Ω·cm,可见光平均透射比大于82%.  相似文献   

10.
应用于检测皮秒激光脉冲的薄膜(Ag-Bao)是一种新型的光电薄膜.基于我们的研究综述了这种超微粒子薄膜的研究进展和应用前景.  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 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   

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 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   

15.
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.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
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   

18.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

19.
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   

20.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

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