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1.
对采用真空气相沉积法在玻璃衬底上制备的稀土Nd掺杂的SnO2薄膜,进行结构、电学及光学特性的测试分析.实验表明:氧化、热处理条件为500 ℃、45 min时样品性能好.采用一步成膜工艺法制备的SnO2薄膜晶粒度较小,随掺Nd浓度的增大,从31.516 nm减小到25.927 nm;两步成膜工艺法制备的SnO2薄膜晶粒度随掺Nd浓度的增大,从45.692 nm增至66.256 nm.XRD分析,掺Nd(5 at%)薄膜沿[110]、[101]晶向的衍射峰加强,薄膜呈多晶结构.掺Nd可使薄膜透光率下降,而薄膜的薄层电阻随热处理温度升高和掺Nd浓度的增大,呈先降后升趋势.  相似文献   

2.
《真空》2017,(3)
采用射频磁控溅射法制备了氧化镓(Ga_2O_3)薄膜,计算了薄膜的O/Ga摩尔比,比值为1.57。研究了后退火对薄膜结构,形貌特征和光学带隙的影响。X射线衍射(XRD)结果表明,退火前的Ga_2O_3薄膜是一种无定形结构。在600℃氧气氛中退火2h后,薄膜开始出现β-Ga_2O_3的(■01)衍射峰;随着退火温度的升高,β-Ga_2O_3(■01)衍射峰进一步增强,并且半高宽从0.61°减小到0.49°。原子力显微镜(AFM)测试结果表明,退火前后薄膜表面的均方根粗糙度从3.47 nm增加到了7.08 nm,晶粒尺寸从19 nm增加到了53 nm。紫外-可见分光光度计(UV-VIS)测试结果表明Ga_2O_3薄膜在250 nm-1500 nm波长范围内的平均透过率在85%以上。利用Tauc公式计算了Ga_2O_3薄膜的光学带隙,带隙宽度在(4.85-5.06)eV之间,且随退火温度增加而减小。分析了表面形貌、光学带隙与薄膜结构之间的关系。  相似文献   

3.
Sol-Gel法制备ZnO:Al透明导电薄膜   总被引:9,自引:0,他引:9  
采用Sol-Gel工艺在普通载玻片上制备出C轴择优取向性、高可见光透过率以及高电导率的Al3+离子掺杂的ZnO透明导电薄膜.利用SEM、XRD等分析手段对薄膜进行了表征.研究结果表明:所制备的薄膜为纤锌矿型结构,表面平整、致密.通过标准四探针法及UVS透射光谱详细研究了Al3+离子掺杂的ZnO薄膜的电学与光学性能.实验发现,当Al3+离子掺杂浓度为0.8%时,前处理温度为400℃,退火温度为550℃,真空退火温度为550℃时,薄膜具有较好的导电性,电阻率为3.03× 10-3Ω@cm,其在可见光区的透过率超过80%.  相似文献   

4.
铜薄膜在100℃~400℃下氧化行为的微观表征   总被引:3,自引:0,他引:3  
本文研究了在100℃~400℃下溅射制备的40nm铜薄膜的氧化行为。利用原子力显微镜(AFM)观察了铜薄膜氧化前期的微观形貌,并利用X射线衍射(XRD)和能量分散X射线谱(EDX)分析了其晶相结构和成份。随着温度的升高,铜薄膜氧化速率明显加快。在100℃下,Cu薄膜表面生成岛状非晶氧化物,温度升高至200℃后,生成Cu2O相的同时Cu薄膜表面产生重构现象,呈现疏松的网状结构。300℃和400℃下Cu薄膜几乎全部氧化,分别形成均匀分布的Cu2O和CuO晶粒。结果表明,利用AFM和XRD能灵敏地跟踪纳米尺度Cu薄膜的氧化过程。  相似文献   

5.
鲍田  王东 《化工新型材料》2019,47(8):102-105
采用溶胶-凝胶法制备了掺铝氧化锌/还原氧化石墨烯(AZO/rGO)薄膜,研究了不同还原氧化石墨烯(rGO)的添加量对薄膜结构和光电性能的影响。采用四探针方块电阻仪测量样品的电学性能,XRD检测薄膜晶体结构,SEM研究薄膜表面形貌,U4100分光光度计检测光学透过率。研究发现,热处理温度为500℃时,AZO/rGO薄膜样品的电阻率随着rGO含量的上升,先减小后增大;当添加量为0.04%(wt,质量分数)时,电学性能最优,样品(002)衍射峰强度最大。光学透过率随着rGO增多而减小,但幅度很小。而热处理温度为530℃时,随着rGO含量的增大,薄膜样品的电阻率逐渐增大,可见光透过率同样有所下降。  相似文献   

6.
采用直流磁控溅射法在不同衬底温度下(27、150、300、450和750℃)制备Ta2O5薄膜。利用X射线衍射、扫描电子显微镜(SEM)和紫外-可见光分光光度计对薄膜的结构、表面形貌和光学性质进行分析研究。实验结果表明,当衬底温度450℃时,薄膜开始结晶。低于450℃,薄膜为无定形态,光学透过率随着衬底温度的升高而升高,在可见光区域最大透过率为85%。薄膜结晶生成晶粒,会对通过的光束产生散射,降低透过率,光学性能下降。这些结果说明衬底温度和薄膜材料的结构、结晶转变温度及光学性质密切相关。  相似文献   

7.
孟凡明  周明飞  宋学萍  孙兆奇 《功能材料》2007,38(11):1773-1776
研究退火温度对薄膜相结构、表面化学组成、形貌及光学性能的影响.采用射频磁控溅射法在单晶硅片和石英玻璃片上负载TiO2薄膜,通过X射线衍射(XRD)、原子力显微镜(AFM)、X光电子能谱(XPS)和紫外可见光谱(UV-vis)对其进行表征.结果表明,常温制备400℃以下退火的TiO2薄膜为无定形结构,400℃以上退火的TiO2薄膜出现锐钛矿相,600℃以上退火的TiO2薄膜开始出现金红石相,退火温度在1000℃以上时样品已经完全转变为金红石相;高温退火薄膜的组成为TiOx;随着退火温度的升高,薄膜透射率下降,折射率和消光系数有所增加.  相似文献   

8.
采用陶瓷靶直流磁控溅射,以玻璃为基底制备2.5wt%Nb掺杂TiO2薄膜,控制薄膜厚度在300~350 nm,研究了不同基底温度下所制得薄膜的结构、形貌和光学特性.XRD分析表明,基底温度为150℃、250℃和350℃时,薄膜分别为非晶态、锐钛矿(101)和金红石相(110)结构.基底温度250℃时,锐钛矿相薄膜的晶粒尺寸最大,约为32 nm.薄膜表面形貌的SEM分析显示,薄膜粗糙度和致密度随基底温度升高得到改善.薄膜的平均可见光透过率在基底温度为250℃以内约为70%,随基底温度升高至350℃,平均透过率下降为59%,金红石相的存在不利于可见光透过.Nb掺杂TiO2薄膜的光学带宽在3.68~3.78 eV之间变化.基底温度为250℃时,锐钛矿相薄膜的禁带宽度最大,为3.78 eV.  相似文献   

9.
采用直流反应溅射并结合热处理工艺制备锡基氧化物薄膜(SnOx,1≤x≤2),利用扫描电镜(SEM)、能谱仪(EDX)、x射线衍射仪(XRD)考察退火温度对薄膜表面形貌、组成和结构的影响,并通过恒流充放电初步考察薄膜的电化学性能。研究结果表明,在400-600℃退火温度下制备的SnOx薄膜表面光滑、结构致密;随着退火温度的升高,薄膜中SnO的含量逐渐减少,SnO2的含量逐渐增加,薄膜的晶粒尺寸增大,大小为30-50nm;600℃退火2h获得的SnOx薄膜具有良好的电化学循环稳定性,有望成为高性能的全固态薄膜锂电池阳极材料。  相似文献   

10.
热氧化法制备二氧化钒薄膜及其相变温度研究   总被引:1,自引:0,他引:1  
采用直流磁控溅射在普通玻璃衬底上沉积金属V膜,然后在空气中热氧化制备VO2薄膜.用X射线衍射仪(XRD)、原子力显微镜(AFM)、傅里叶变换红外光谱仪(FT-IR)和X射线衍射光电子能谱仪(XPS)分析氧化温度对薄膜的微观结构、光学透过率、相变温度及其组分的影响.结果表明:金属V膜在空气中400℃热氧化1 h得到相变温...  相似文献   

11.
In biological environments, the surface of nanoparticles (NPs) are modified by protein corona (PC) that determines their biological behavior. Unfortunately, in vitro tests still give different PC than in vivo tests causing in vitro–in vivo discrepancy; hence, in vitro studies are not indicative for the NPs' behavior in vivo. Here is demonstrated that PC in vitro is strongly influenced by the type of extracellular fluid (ECF), blood or lymph, by their high and low flow conditions and transitions between ECFs, and a combination of these parameters. As a result, this in vitro study approaches fluidic and dynamic variations to which NPs are exposed in vivo: different ECF that NPs encounter first in different injection routes, different transitions in‐between ECFs during circulation, and simultaneous change in the exposed flow in these transitions. The most‐abundant proteins in PCs are found to be not the most abundant in ECFs, but those having high affinity for binding to the surface of NPs. Moreover, some proteins are differently abundant in PCs at different flows, which indicate force‐promoted binding, catch bonds. These results suggest that future in vitro studies should consider more complex incubation conditions to improve the in vitro–in vivo consistency necessary for translational research.  相似文献   

12.
This Paper presents a comparative study of minces prepared from headed and gutted sardines and minces prepared from whole sardines, with a view to avoiding unnecessary product handling and improving yields. Certain additives (cryoprotectants and antioxidants) were blended into some of the mince lots in an attempt to extend their storage life, and in one of the lots the mince was washed prior to mixing. The minces were prepared by extrusion and the lots were fashioned into 4 cm thick 700 g blocks, frozen in a horizontal plate freezer until a core temperature of −20°C was attained, vacuum packed and stored at −20°C for 12 months. Proximate analysis, minerals analysis (Na,K,Mg,Ca,Fe and Cu) and yield measurements were carried out prior to freezing. Protein solubility, emulsifying capacity, cooking loss, K value, pH, TBA index, viable germ counts, entero and coliform bacteria, instrumental texture analysis and sensory analysis were periodically measured. The results obtained can be summarized as follows: the method of extrusion appears to be particularly well adapted to whole fish with regard to the avoidance of handling and improving yields. In relation to mineral content the only appreciable difference is a higher sodium content in minces made from whole fish (E lots) than in minces made from gutted and headed sardines (D lots), while in the washed lots there was an appreciable decreases in the amounts of Cu, Fe, Mg and K. Protein solubility stayed at higher levels in the E lots than in the D lots, though it was high in both types of mince at the end of storage: the use of protein cryoprotectants is advisable particularly in the washed D lot (DL) and in the E lots when storage of >6 monts is required. The emulsifying capacity, which was initially higher in the E lot than in the D lot, stabilized after the second month of storage. The effect of the protein cryoprotectants was to increase slightly the emulsifying capacity, which remained higher than in the control lots throughout the storage period, even in the DL lot, which the authors feel is important with regard to the use of these minces in sausage-type products. Cooking loss was initially higher in the D lots, but after the fourth month of storage it was the same for both types. The protein cryoprotectants reduced cooking loss and were more effective in the E lots. Due to fluctuations in K values obtained, the authors do not regard them as a reliable indicator of product quality. The pH was slightly more basic in the E lots than in the D lots, and pH increased in the additive-containing lots, especially in the washed mince preparation. The TBA index only showed significant differences between the D and E lots in the final test performed. The antioxidants appeared to be more effective in the E lots than in the D lots. Washing also delayed the onset of randicity, probably through the removal of fat and catalysts with the wash water. No synergistic effect was observed between the protein cryoprotectants and the antioxidants. The total initial count of micro-organisms was substantially higher in the E lots than in the D lots because of the intestinal content, though the levels equalized during storage and at no time exceeded allowable limits. Washing did not significantly decrease germ counts. The initial excessive amounts of enterobacteria in the E lots decreased during storage, whereas the level of caliform bacteria, on the other hand, remained constant. In the E lot without additives (ESS), however, Escherichia coli was detected prior to freezing but not in any of the subsequent analyses. In general, texture as determined by instrumental methods (hardness, firmness, elasticity, and cohesiveness) gave higher values for the D lots than for the E lots. Washing increased hardness and firmness while cryoprotectants reduced them. Cooking considerably hardened the samples in the case of the D lots but did not cause variations in the E minces. Hardness and firmness remained quite stable, although there was a slight increase in the cryoprotectants-free lots and washed minces. Elasticity tended to increase in the E lots during storage, and this effect was more pronounced in the cryoprotectants-free lots; cryoprotectants had the effect of decreasing elasticity and stabilizing it in the D lots, although they were higher in the D lots than in the E lots. Elasticity and cohesiveness remained constant in the washed mince. Cohesiveness increased in all the lots during storage, and the cryoprotectants exerted no effect on this parameter. In connection with the sensory analysis, a certain sweet taste was perceived in the cryoprotectants-containing D lots, slightly reducing the quality of the product, though it was not found unpleasant and was barely detectable in the E lots. The typical sardine flavoured lots by the washed mince reduced its acceptance, though this opens up a series of technological possibilities for it. A rancid taste was detectable in the ESS lot after five months in storage, in the E lot with protein antidenaturants (ESP) after eight months, and in the E lot that contained antioxidants (ESAO) and protein antidenaturants and antioxidants (ESA), in the last test carried out.  相似文献   

13.
Earlier advances in air separation and liquefaction include improvements in: overall product recovery, feed air purification, more efficient heat exchange, optimum plant control, gradual improvement in efficiency of compressors and expanders. More recent improvements include use of structured packing in distillation columns, molecular sieve adsorbents for air purification, computer simulation and control of plants, and increased machinery efficiency. Advances in fabrication and construction techniques are aimed at reducing capital costs. This paper reviews modern developments in air separation and liquefaction and attempts in this context to suggest features that might be expected to arise in the early part of the third millennium.  相似文献   

14.
In 1947, Kê observed a large relaxation peak around 0.46Tm in polycrystalline aluminum. This peak being absent in single crystal, Kê concluded that this relaxation effect was due to grain boundary sliding (GBS). In the 1970s, Woirgard, in the same temperature range, observed a peak in single crystal. Later on Rivière, Esnouf, and No systematically studied different relaxation effects in single and polycrystals and they concluded that the Kê peaks, as well as the other relaxations observed in this temperature range, are due to dislocation motion, the mechanism being probably the climb of jogs. More recently, in Ni–Cr, Cao clearly observed the presence of a large relaxation peak in polycrystals, which is absent in single crystal. He showed that the peak is due to grain boundary sliding, the mechanism of which is the climb of dislocations in the grain boundaries. Does a relaxation effect due to grain boundary sliding exist in metals? The question is still open and will be discussed in this paper considering recent results of the Chinese, French, Spanish and Swiss school.  相似文献   

15.
北衙金多金属矿床地质特征与成因   总被引:1,自引:0,他引:1  
详细讨论了北衙矿区的地质特征,通过对勘探资料的深入研究和野外观察,初步确定,北衙矿区存在两期岩浆活动,早期的石英正长斑岩、正长斑岩等近南北向分布,晚期的黑云正长斑岩、煌斑岩脉等呈近东西向展布。矿化主要与近南北向岩体关系密切。北衙地区存在五种矿床类型,即矽卡岩型铁金矿床,其形成时代相对较早,分布于万硐山矿段、马头湾矿段等地;斑岩-隐爆角砾岩筒型金铜矿床,分布于北衙矿区的西矿带的万硐山-红泥塘(观音箐一带,形成时代相对较晚,并叠加于早期的矽卡岩型矿床之上;裂隙-溶洞型铁金矿床,主要分布于北衙矿区的东矿带的笔架山一带,属强氧化高品位金矿石;砂岩型铁金矿床,分布于本区的三叠系下统腊美组(T1l)砂岩中,呈似层状产出,成矿潜力巨大;红土型金矿床,主要分布于北衙盆地浅表部位的丽江组(E2l)和第四系堆积物中,易采易选,可供利用。北衙地区下一步勘探和研究的主要矿床类型应是深部具有潜力的斑岩(隐爆角砾岩筒型金铜矿床和三叠系下统碎屑岩中产出的砂岩型铁金矿床。  相似文献   

16.
葛金林  肖海平  闫大海 《发电技术》2020,41(5):552-4141
为了研究流化床生物质气化协同处置生活垃圾衍生燃料过程中重金属的迁移转化规律,在湖北某循环流化床气化炉耦合燃煤发电厂进行掺烧试验。研究表明重金属主要赋存于飞灰和炉渣中。空白工况下86.2%的Cr赋存于飞灰中,13.3%于炉渣中;75.5%的Pb在飞灰中,23.8%在炉渣中;79.5%的As迁移至飞灰中,11.7%在炉渣中。RDF工况下75.8%的Cr迁移至飞灰,20.7%迁移至炉渣;44.6%的Pb存在于飞灰中,52%存在于炉渣。协同处置后,重金属在飞灰和炉渣中的分配比例明显发生了变化,飞灰中重金属含量减少12.5%~31.3%,炉渣中重金属增加7.33%~20.1%,气化气的引入改变了炉内重金属的分配情况。协同处置可以有效处理生活垃圾,对固废中的热量进行资源化利用,且出炉物料中重金属含量均低于我国现行标准限值。  相似文献   

17.
Hollow‐structured mesoporous materials (HMMs), as a kind of mesoporous material with unique morphology, have been of great interest in the past decade because of the subtle combination of the hollow architecture with the mesoporous nanostructure. Benefitting from the merits of low density, large void space, large specific surface area, and, especially, the good biocompatibility, HMMs present promising application prospects in various fields, such as adsorption and storage, confined catalysis when catalytically active species are incorporated in the core and/or shell, controlled drug release, targeted drug delivery, and simultaneous diagnosis and therapy of cancers when the surface and/or core of the HMMs are functionalized with functional ligands and/or nanoparticles, and so on. In this review, recent progress in the design, synthesis, functionalization, and applications of hollow mesoporous materials are discussed. Two main synthetic strategies, soft‐templating and hard‐templating routes, are broadly sorted and described in detail. Progress in the main application aspects of HMMs, such as adsorption and storage, catalysis, and biomedicine, are also discussed in detail in this article, in terms of the unique features of the combined large void space in the core and the mesoporous network in the shell. Functionalization of the core and pore/outer surfaces with functional organic groups and/or nanoparticles, and their performance, are summarized in this article. Finally, an outlook of their prospects and challenges in terms of their controlled synthesis and scaled application is presented.  相似文献   

18.
The exploration of quantum-inspired symmetries in optical and photonic systems has witnessed immense research interest both fundamentally and technologically in a wide range of subject areas in physics and engineering. One of the principal emerging fields in this context is non-Hermitian physics based on parity-time symmetry, originally proposed in the studies pertaining to quantum mechanics and quantum field theory and recently ramified into a diverse set of areas, particularly in optics and photonics. The intriguing physical effects enabled by non-Hermitian physics and PT symmetry have enhanced significant application prospects and engineering of novel materials. In addition, there has been increasing research interest in many emerging directions beyond optics and photonics. Here, the state-of-the art developments in the field of complex non-Hermitian physics based on PT symmetry in various physical settings are brought together, and key concepts, a background, and a detailed perspective on new emerging directions are described. It can be anticipated that this trendy field of interest will be indispensable in providing new perspectives in maneuvering the flow of light in the diverse physical platforms in optics, photonics, condensed matter, optoelectronics, and beyond, and will offer distinctive application prospects in novel functional materials.  相似文献   

19.
HL-1M装置边缘扰动和流速的实验研究   总被引:2,自引:0,他引:2  
利用一组马赫探针研究HL-1M装置刮离层和边缘等离子体流在欧姆放电、壁硼化、偏压抽气孔栏、偏压电极、低混杂波电流驱动、电子回旋共振加热、弹丸注入、分子束注入、激光吹气和补充送气等情况下的平行流马赫数、离子饱和电流扰动、平行流速度剪切和极向流速度的分布。实验中发现局部等离子体电位快速变化,改变了电场分布,改变了边缘等离子体的流速和方向。从而改善了等离子体约束性能。  相似文献   

20.
提出材料学中的两个基本关系式:P=f(e,S)和S={E,R},式中,P,e,S,E及R分别是性能,环境,结构,组元的集合及关系的集合。微观材料学的功能(P)取决于它的结构(S),第一节讨论它的五组元(性能,环境,结构,过程及能量)之间的关系(R);第二节讨论材料能量学中九组元之间的关系(R);第三节列出材料能量学九组元(E)的内涵和警句;第四节总结能量在材料学中的作用。  相似文献   

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