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刘树载 《数理化学习(高中版)》2004,(1)
一、选择题1.欲计划实现全球卫星通讯需发射77颗卫星,这与铱(Ir)元素的原子序数恰好相等,因此称为“铱星计划”.已知铱的一种同位素是191 77 Ir,则其核内的中子数为( ) 相似文献
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为了在低温衬底(＜ 500℃)上制备出高品质纳米金刚石薄膜,使用辉光等离子体辅助热丝化学气相沉积法,用甲烷、高纯氢为源气体,P型Si (100)为衬底材料,在低温条件下合成了纳米金刚石薄膜,利用Langmuir探针对合成过程进行了实时原位诊断,研究了电子温度Te和电子密度ne的空间变化规律,探讨薄膜生长机理.对所合成的样品,利用扫描电子显微镜、Raman光谱仪、X射线衍射进行了分析.结果表明,实验所得样品为高品质、结晶完善、表面光滑的纳米金刚石薄膜,SEM形貌表明薄膜中晶粒的粒度为40～90 nm,Raman光谱在1331.5 cm-1处出现了金刚石的(111)特征声子峰.XRD谱在2θ =43.90、75.30处出现了金刚石的(111)、(220)特征衍射峰.实验得出了低温合成纳米金刚石薄膜的最佳工艺条件:①甲烷体积百分比浓度为0.6％;②反应室气压为5 kPa;③气体流量在1100～1300 mL/min范围内成核密度较高,并以(100)、(111)面为主,晶粒的平均粒度小于100 nm;在流量为1300 mL/min时,晶粒的生长表现为一定的定向生长. 相似文献
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采用化学溶液沉积法在Si(001)衬底上制备Ni0.7Zn0.3Fe2O4铁氧体薄膜,XRD谱表明样品具有单相的尖晶石结构;扫描电子显微镜结果表明样品平均颗粒尺寸随着退火温度的上升从10 nm增加到32 nm。NZFO铁氧体薄膜磁性能与退火温度有强烈的依赖关系,薄膜的矫顽力从退火温度为500℃时的25 Oe增加到900℃时的80 Oe,饱和磁化强度也由146emu/cm3增加到283 emu/cm3,这对于现代电子器件微型化有着非常重要的意义。 相似文献
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在航空透明件领域,厚聚合物基底上透明导电薄膜的断裂韧性是量化抗开裂性的关键力学特性,因此基于纳米压痕和通道开裂试验评估了薄膜的断裂韧性。采用磁控溅射法将氧化铟锡(ITO)薄膜沉积在聚碳酸酯(PC)基底上。纳米压痕试验中,纳米压痕在ITO薄膜上引起脆性断裂,通过对所得的载荷-深度曲线进行积分来计算断裂韧性;通道开裂试验中,使用原位拉伸法获得开裂应变,并结合力学模型计算断裂韧性。结果表明,不考虑残余应力时,2种测试方法获得了相对一致的断裂韧性,500 nm厚ITO薄膜的断裂韧性为1.62～1.81 MPa·m1/2;对于200 nm以下厚度的薄膜或存在大残余应力的薄膜,宜选择通道开裂试验以确定断裂韧性。 相似文献
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程奕天 《深圳职业技术学院学报》2021,(1)
采用Al+α-Al2O3复合材料及Al100-xCrx(x=10,20,30)合金作为靶材,用反应磁控溅射将α型籽晶引入氧化铝基薄膜中,研究了籽晶对氧化铝基薄膜的元素比例、相组成、结构特征、表面形貌及纳米硬度的影响.结果显示,在550℃时溅射Al+α-Al2O3复合靶所得的薄膜由单相的α-Al2O3组成,而在同一温度下采用Al70Cr30合金靶所制得的薄膜中检测到α-(Al0.7Cr0.3)2O3固溶体.纯α-Al2O3薄膜及α-(Al0.7Cr0.3)2O3固溶体薄膜的纳米硬度分别达到~23.5GPa和~28.5GPa. 相似文献
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《赣南师范学院学报》2015,(6):31-34
采用旋涂工艺,以K9玻璃为衬底,制备低表面粗糙度的惯性约束聚变(ICF)分解实验用的聚苯乙烯(CH)和聚氯乙烯(PVC)平面薄膜靶,对它们的厚度、宽度和表面光洁度等靶参数进行测量.结果表明,CH和PVC平面薄膜靶的厚度分别为18μm和6μm,对应的宽度分别为200μm和300μm.CH和PVC平面薄膜靶都具有较好的表面光洁度,它们平均粗糙度Ra的最大值分别3.7 nm和4.5 nm,TIR表面最高点与最低点差值TIR的最大值分别58.4 nm和56.8 nm. 相似文献
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对电化学沉积淀粉薄膜的沉积参数进行了系统地研究,并采用正交试验对电化学沉积淀粉薄膜的工艺条件进行了优化;然后选取一组最佳电化学沉积工艺参数,制备了淀粉薄膜样品;最后还用扫描电子显微镜(电极离子M)、X--射线衍射仪(XRD)以及对制备的薄膜的性能进行了袁征,研究表明,制备的淀粉薄膜的化学计量比接近1:1,其性能较好. 相似文献
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用电化学阳极氧化法制备了一定孔隙率的多孔硅样品,然后用脉冲激光沉积法以PS为衬底生长一层ZnS薄膜.用X射线衍射仪、扫描电子显微镜和荧光分光光度计分别表征了ZnS薄膜的结构、形貌和ZnS/PS复合膜的光致发光性质.XRD结果表明,制备的ZnS薄膜沿β-ZnS(111)方向择优生长,结晶质量良好,但衍射峰的半峰全宽较大;SEM图像显示,ZnS薄膜表面出现一些凹坑,这是衬底PS的表面粗糙所致.室温下的光致发光谱表明,沉积ZnS薄膜后,PS的发光峰蓝移.把ZnS的蓝绿光与PS的橙红光叠加,在可见光区450~700 nm形成了一个较宽的光致发光谱带,ZnS/PS复合膜呈现较强的白光发射. 相似文献
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A kind of pyrazoline derivative 1,3-bis(phenyl)-5-(2-phenanthrene)-2-pyrazoline(TPp) was synthesized in order to obtain stable
film and applied to organic electroluminecsent diode as hole transporting material. Two devices with structures as indium-tin-oxide(ITO)
TPP (50 nm)/tris-(8-hydroxyquinoline) aluminum(Alq3) (50 nm)/Al (150 nm) and ITO /TPP (50 nm)/lithium
tera-(8-hydroxy-uinolinato)boron(LiBq4 (50 nm)/Alq3 (5 nm)/Al (150 nm) were fabricated, they showed good electroluminescent(EL)
performance and TPP was proved to be a good hole transporting material. 相似文献
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WANG Dong-ming Zhang Bu-xin SUN Ling-ling JIANG Xue-yin ZHANG Zhi-lin XU Shao-hong MA Chang-qi WANG Jian-hua ZHANG Bao-wen School of Material Science Engineering Shanghai University Shanghai China Institute of Photographic Chemistr 《上海大学学报(英文版)》2000,(Z1)
1 IntroductionOrganic electrolUminescent (EL) devices have beenexpected tO serve as a new ace of flat display since Tangand co-workerS first reposed high-perfonnance orgallicEL devices.["2] Their success was based on a multilayerstrUctUre which had an emitting layer and a caberdisPOrting layer. F~rmore, Adachi and co-workersdeVeloped the multilayer strUctUre and Proposed threefimdamental strUctUres for orghoc EL devices, namelythe single hetero-A (SH-A), single hetero-B (SH-B) andd… 相似文献
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Pd77Cu6Si17 （PCS） tbin film metallic glasses （TFMGs） with high glass forming ability and hardness were selected as a hard coating for improving the surface hardness ofAZ31 magnesium alloy. Both microindentation and nanoindentation tests were conducted on specimens with various PCS film thicknesses from 30 to 2000 nm. The apparent hardness and the relative indenta- tion depth （fl） were integrated using a quantitative model. The interaction parameters involved and relative hardness values were extracted from iterative calculations. According to the results, surface hardness can be enhanced greatly by PCS TFMGs in the shallow region, followed by gradual decrease with increasing fl ratio. In addition, specimens with thinner coatings （e.g., 200 nm） showed greater substrate-film interaction and those with thick coatings （e.g., 2000 nm） became prone to film cracking. The op- timum TFMG coating thickness in this study was estimated to be around 200 nm. 相似文献
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以电合成前驱体Ti(OEt)4直接水解法和电沉积法制备Ti基纳米TiO2-碳纳米管复合膜载P(tPt/nanoTiO2-CNT)复合电极。透射电镜(TEM)和X射线衍射(XRD)测试表明,锐钛矿型纳米TiO2粒子和Pt纳米粒子(粒径约8nm)均匀地分散在碳纳米管表面。通过循环伏安法研究Pt/nanoTiO2-CNT电极对Ce3+的电催化性能,Ce3+氧化峰电位约为1.27V(vs.SCE),比Pt/nanoTiO2电极负移30mV,峰电流约高45mA·cm-2。 相似文献
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以透明导电玻璃(TCO)为衬底,用硝酸锌水溶液作为电解液,采用阴极电沉积法合成了ZnO薄膜.通过改变电解液浓度、温度和沉积电压等实验条件,系统研究了锌氧化物薄膜材料的电化学沉积过程.用扫描电镜、X射线衍射、紫外-可见光谱法等技术对沉积物的形貌、结构及光学性质进行了表征.结果表明,通过控制电解液的浓度和温度及沉积电压等反应条件可以制备出不同形貌的ZnO薄膜.XRD结果表明,所得的ZnO纯度高且呈六方纤锌矿结构;光谱法研究表明,该薄膜在344 nm和552 nm处有两个吸收峰,禁带宽度为3.25 eV. 相似文献
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Evolution of Surface Oxide Film of Typical Aluminum Alloy During Medium-Temperature Brazing Process简 总被引：1，自引：0，他引：1
The evolution of the surface oxide film along the depth direction of typical aluminum alloy under medium-temperature brazing was investigated by means of X-ray photoelectron spectroscopy （XPS）. For the alloy with Mg content below 2.0wt%, whether under cold rolling condition or during medium-temperature brazing process, the en-richment of Mg element on the surface was not detected and the oxide film was pure Al2O3. However, the oxide film grew obviously during medium-temperature brazing process, and the thickness was about 80 nm. For the alloy with Mg content above 2.0wt%, under cold rolling condition, the original surface oxide film was pure Al2O3. However, the Mg element was significantly enriched on the outermost surface during medium-temperature brazing process, and MgO-based oxide film mixed with small amount of MgAl2O4 was formed with a thickness of about 130 nm. The alloy-ing elements of Mn and Si were not enriched on the surface neither under cold rolling condition nor during medium-temperature brazing process for all the selected aluminum alloy, and the surface oxide film was similar to that of pure aluminum, which was almost entire Al2O3. 相似文献
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张莉 《黄河科技大学学报》2007,9(4):53-56
迪斯尼动画片《木兰》在再现“他者”的过程中对本土文化进行了东方化和美国化。原作《木兰辞》所蕴涵的中国传统文化受到美国主流文化的置换。在这一过程中，第三世界的文化受到文化霸权强有力的渗入和强权干预，导致自己的民族文化遭受边缘化。面对这种后殖民文化霸权，第三世界文化应积极寻求走向世界的新的可能性。 相似文献
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Studies on characteristics of nanostructure of N-TiO2 thin films and photo-bactericidal action 总被引：1，自引：0，他引：1
Pseudomonas aeruginosa strain （AS 1.50） and Bacillus subtilis strain （AS 1.439） from Ming lake were decomposed by photocatalytic nanostructure N-TiO2 thin films in a photo-reactor under UV irradiation. The different thickness nanostructure N-TiO2 thin films coated on mesh grid were prepared by sol-gel method and immobilized at 500 ℃ （films A） or 350 ℃ （films B） for 1 h in a muffle furnace. The results showed that N-TiO2 thin film B （8.18 nm thickness, 2.760 nm height and 25.15 nm diameter） has more uniform granular nanostructure and thinner flat texture than N-TiO2 thin film A （12.17 nm thickness, 3.578 nm height and 27.50 nm diameter）. The bactericidal action of N-TiO2 thin film A and film B for Pseudomonas aeruginosa strain （AS 1.50） and Bacillus subtilis varniger strain （AS1.439） were investigated in this work. More than 95% of photocatalytic bactericidal efficiency for Pseudomonas aeruginosa strain （AS 1.50） and 75% for Bacillus subtilis strain （AS 1.439） were achieved by using N-TiO2 thin films-B for 70-80 rain of irradiation during the photo-bactericidal experimental process. The results indicated that the photo-induced bactericidal efficiency of N-TiO2 thin films probably depended on the characteristics of the films. 相似文献
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管红星 《南京师范大学文学院学报》2001,(2):62-69
从电影观赏角度剖析电影作品所包蕴的化价值以及电影化阐释的价值。电影作品中可供或易被电影观众接受、理解、阐释乃至借鉴的电影化价值主要有民俗学价值、社会学价值、生命学价值、哲学价值以及宗教学价值。电影观众各具个性的观影行为使静态的、内容丰富的电影化得以动态地、多姿多彩地展现。电影化阐释活动在满足和提高电影观众审美情趣的同时，其本身也具有实现、完善和发展电影化的艺术价值。 相似文献