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1.
用角分布XPS法研究了MOD法制得的YBCO膜在热处理过程中膜的表面元素浓度变化以及膜与村底ZrO_2之间的原子扩散和固态化学反应。结果表明无论是薄膜(约0.1 μm)和较厚的膜(约1~1.5 μm), 在大约530~720 ℃的温度范围内加热后都发生铜表面富集和钡表面浓度偏低。在800 ℃以上加热后铜的表面浓度显著降低, 温度愈高, 降低愈甚。膜与衬底之间的化学反应也随温度升高而加剧。例如薄膜在890 ℃加热后钡向ZrO_2衬底扩散, 膜中的铜仍以+2价为主; 在950 ℃加热后衬底表面生成了富钡层, 而铜则主要以+1价的形式存在于富钡层表面。与厚膜相比, 在800 ℃以上薄膜与衬底的原子扩散和固态化学反应对于膜超导电性的损害更显著。  相似文献   

2.
碳钢表面稀土转化膜的XPS和AES研究   总被引:10,自引:1,他引:10  
用浸渍法在A3钢表面上获得了稀土转化膜,此膜呈均匀的金黄色,有良好的装饰效果。硫酸铜点滴、盐水浸泡、硫化氢气体等加速腐蚀试验以及膜层的电化学测试均证实此膜具有一定的耐蚀性能。膜层的XPS9X射线光电子光谱)分析结果表明,膜层由铁、铈、氧等元素组成;在膜层的表面,铁以Fe^3+,铈以Ce^4+状态存在,在膜层的内部,铁以Fe^3+及Fe^3+,铈以Ce^3+和Ce^4+状态存在;从AES(俄歇Fe^  相似文献   

3.
微胶囊膜表面化学组成的XPS分析   总被引:1,自引:0,他引:1  
采用XPS表面表征技术对生物微胶囊膜表面化学组成进行了分析。结果表明,海藻酸钠_壳聚糖_海藻酸钠(ACA)微胶囊表面带负电荷的含C基团与带正电荷的含N基团的相对百分含量分别为30·6%与60·4%,而海藻酸钠_聚赖氨酸_海藻酸钠(APA)微胶囊分别为42·3%与30·0%,因此ACA微胶囊表面比APA微胶囊带更多的正电荷,更有利于蛋白质吸附与细胞粘附。为深入了解生物微胶囊表面引起的机体反应过程、改进微胶囊性能,提供了理论依据。  相似文献   

4.
XPS和AES研究锡表面的防变色膜   总被引:2,自引:0,他引:2  
通过比较多种防锡变色剂的防变色效果,发现乙二胺四甲叉膦酸(EDTMP)是一种优良的防锡变色剂。用XPS、AES及Raman光谱探讨了EDTMP的防变色机理,结果表明EDTMP在锡表面形成了一种耐蚀性保护膜。在深度剖析曲线的元素组成近似恒定区测得膜的相对原子浓度(A.C.%)为:O 48.0%;Sn 10.7%;N 7.7%;C 23.1%;P 10.5%。  相似文献   

5.
罗兴华  方景礼 《化学学报》1985,43(3):278-281
金属的电抛光应用越来越广泛.但电抛光机理至今仍不很清楚.我们曾用 XPS 和AES 研究了不同槽电压下电抛光铜表面的组成和物种,确认其表面均为纯铜,不存在含磷固体膜.本文用 XPS 研究电抛光液中1-羟基乙叉-1,1-膦酸(HEDP)浓度、抛光液的 pH 及其接受体(H_3PO_4,HEDP 和 HEDP H_3PO_4)变化时铜的表面组成,并进一步证明,电抛光时形成的粘液膜是水溶性膜,铜表面在不同抛光条件下并不形成难溶的含磷固体膜.通过电子能谱对固化后粘液膜组成和深度分布的研究确定,粘液膜可能是铜的多核聚合混合配体配合物,其组成可近似地表示为[Cu_4(PO_4)(HEDP)]_n.  相似文献   

6.
为了实现YBa2Cu3O7-x(YBCO)涂层导体在电力工业中的实际应用,必须有效增加YBCO超导层的厚度。提出一个强磁场辅助TFAMOD法制备YBCO厚膜的新工艺,并从磁热力学和磁性物理出发理论分析其可行性。沿垂直基底平面方向施加强磁场时,磁场将促进c轴取向YBCO晶核的形成,诱导厚膜中非c轴取向晶核转动到c轴平行磁场取向的位置。另外,取向晶粒间磁性相互作用力使晶粒沿磁场方向定向聚合,有利于获得致密的厚膜。因此,强磁场辅助TFA—MOD法有望制备高临界电流密度的YBCO织构厚膜。  相似文献   

7.
XPS法测量铝箔表面氧化铝的厚度   总被引:2,自引:0,他引:2  
介绍了一种无需溅射、无需变角,只需一次简单的XPS(X射线光电子能谱)窄扫描,即可根据谱图中氧化态和金属态的相对强度算出铝金属表面氧化铝的厚度。用该法测量了一系列不同方法处理的铝表面氧比铝厚度,并与椭偏法及NRA法(核反应分析法)测定结果进行了对比,结果表明,该法是一种简便准确的膜厚测量法。  相似文献   

8.
用X射线光电子能谱(XPS)法研究了在基体ZrO上以含氧酸盐热反应法制得的YBaCuO超导膜的表面状态、组成及各成分元素的结合能,特别是Ar~+刻蚀前后膜表面组成和状态的变化,并与另一条件下制得的Y_2BaCuO_5非超导膜作了比较。探讨了Ar~-刻蚀前后,超导膜表面状态和组成变化的原因。确定了YBa_2Cu0超导膜中各成分元素的结合能:Y=156.3eV;Ba=778.5eV;Cu=933.5eV和Os=528·3eV,529.4eV。结果还表明:超导膜表面容易受H_2O和CO的侵蚀,生成BaCO。  相似文献   

9.
X-ray photoelectron spectroscopy(XPS)was used to study two different oxidation treatments on the GaAs(100)surface———the thermal oxidation in the air,and the ultraviolet-light oxidation in the UV-ozone. A series of properties including the oxide composition,chemical states,the surface Ga/As atomic ratio and the thickness of the oxide layer grown on GaAs surface were compared. The results indicate that the oxide composition,the surface Ga / As atomic ratio and the thickness of the oxide layer oxide on GaAs surface are different for different oxidation methods. The oxides on GaAs surface grown by thermal oxidation in the air are composed of Ga2O3,As2O5,As2O3 and elemental As;and the Ga/As atomic ratio is drifted off the stoichiometry far away. The Ga/As atomic ratio of oxide layer on GaAs surface is increases with the thickness of oxide. However,the oxides on GaAs surface grown by UV-ozone are made up of only Ga2O3 and As2O3,As2O5 and elemental As are not detected,the Ga/As atomic ratio is close to unity. The thickness of oxide layer on GaAs can be controlled by the UV exposing time. The mechanism of oxidation of GaAs is also discussed. The UV-light radiation not only causes the oxygen molecular excited forming atomic oxygen,but also induces the valence electrons of the GaAs excited from the valence band,and then the reactivity of Ga and As atom increase,and they can easily react with the excited atomic oxygen at the same reactive velocity.  相似文献   

10.
采用光辅助金属有机物化学气相沉积(MOCVD)法,在生长有CeO2/YSZ/Y2O3(YSZ为Y稳定的ZrO2)缓冲层的双轴取向Ni衬底上进行了YBa2Cu3O7-x(YBCO)外延膜生长,并与LaAlO3(100)[LAO(100)]单晶衬底上的YBCO外延膜生长进行了对比.发现在Ni衬底上c轴取向YBCO外延膜的生长温度比LAO衬底上的生长温度低约30℃,但生长速度更快.经分析认为,这种差别主要是由于Ni衬底的热导率比LAO衬底高造成的.Ni衬底及LAO衬底上生长的c轴取向YBCO外延膜的超导极限电流密度(Jc)分别约为0.5 MA/cm2及1.8 MA/cm2.  相似文献   

11.
高聚物界面的能量、结构等性质,对理论研究和实际应用都是极为重要的.因为许多聚合物材料都具有一个或多个界面的多相结构,这些界面的结构和强度等,显著地影响着这些多相材料的物理、力学性能等,而它们之间的关系,是一个极为复杂的问题,只有综合界面科学、流变学、...  相似文献   

12.
A new process for lamination of polymer films by "bulk surface photografting" has been developed. The chemicalcomponent of the invention is that the curing of reactive solution between two substrates is initiated by the surface freeradicals produced by aromatic ketones and surface-hydrogen of substrates. Using the new approach, two or more polymerfilms are bonded together by a grafted polymer network which is grafted to adjacent substrate surfaces. The technique hasbeen applied to film substrates of different polymers such as polyolefins, polyesters. and polyamides which have abstractablehydrogens at the surface. The photolaminated film composites containing carrier films and an intermediate functional film of low permeability give strong laminates with high barrier properties, e.g. for oxygen and air.  相似文献   

13.
用FTIR和XPS研究ACF的表面结构   总被引:3,自引:1,他引:3  
采用红外光谱(FTIR)及X光电子能谱(XPS),系统分析了纤维碳化各阶段的结构、不同程度活化的ACF的结构以及低温氧化后和热处理后ACF的结构,提出了ACF表面结构模型。  相似文献   

14.
采用大分子单体法合成了一系列聚苯乙烯接枝壬基酚聚氧乙烯 (PS g NPEO)两亲共聚物 ,采用溶液铸膜法将其在PET表面制膜 ,并利用扫描电子显微镜 (SEM) ,X射线光电子能谱 (XPS) ,衰减全反射红外光谱(ATR)和水接触角 (CA)等手段研究了共聚物组成、铸膜溶剂及浓度对共聚物膜表面形貌、组成及水浸润性能的影响 .结果表明 ,两亲接枝共聚物在不同条件下可形成规则的表面微孔 ,共聚物中NPEO含量越高 ,共聚物膜表面微孔孔径越大 ,对应的水接触角越小 .以THF为铸膜溶剂时 ,制膜浓度越大 ,共聚物膜表面微孔孔径越大 ,对应的水接触角越小 ;而以甲苯为溶剂时 ,制膜浓度对共聚物膜表面形貌影响不大 ,但水接触角要较THF体系显著降低 ,水接触角与浓度关系与THF体系相反 ,制膜浓度越大 ,对应的水接触角越大 .制膜浓度相同时 ,THF作溶剂 ,共聚物膜微孔较大 ,表面亲水组分含量较低 ;以甲苯为溶剂 ,微孔较密 ,表面亲水组分较高 .  相似文献   

15.
报道了一种简便的调控聚合物材料表面结构及浸润性能的方法.利用流延成膜和纳米二氧化硅粒子的印迹修饰作用,制备出3种具有不同表面结构的聚氯乙烯(PVC)膜,膜的浸润性能表现为与水的接触角从103°的疏水性变为65°的亲水性,再改变至130°的疏水性.扫描电镜结果表明印迹修饰后的PVC膜具有纳米和微米尺寸的凹凸表面结构.通过对比实验证实了溶剂氯仿和NaOH溶液并不影响膜表面的疏水性能.  相似文献   

16.
In this work, the thermodynamic parameters for the adsorption of water vapor on untreated silica gel and silica gel treated with hygroscopic salts and silane coupling agent were determined by Inverse Gas Chromatography (IGC) in the infinite dilution region. The desorption activation energies of the water vapor on virgin and modified silica gels were estimated by using the Temperature Programmed Desorption (TPD) technique. The interactions between the water and the virgin and modified silica gels were discussed. Results showed that the thermodynamic parameters and desorption activation energy of water vapour on the silica gels increase with decreasing pore size and increasing the surface hydrophilic properties. The desorption activation energy of virgin and modified silica gels was found to increase with increasing the thermodynamic parameters. The larger the adsorption parameters and the desorption activation energy were, the interactions between water and virgin and modified silica gels were.  相似文献   

17.
1. INTRODUCTIONSilica gel is an amorphous inorganic polymer composed of siloxane (Si-O-Si) groups in the inner region and silanol (Si-OH) groups distributed on the surface [1]. Silanol groups can be easily functionalized by different chemical procedures. …  相似文献   

18.
硬脂酸表面改性碳酸钙粉末的热分析及其表面性质变化   总被引:5,自引:0,他引:5  
硬脂酸表面改性碳酸钙粉末的热分析及其表面性质变化李新军廖景发*瞿龙*吕海波(中南工业大学粉末冶金研究所*化学系长沙410083)关键词表面改性热分析碳酸钙粉末表面性质硬脂酸中图分类号O623.611,O647.2碳酸钙粉末是一种重要的无机化工产品,广...  相似文献   

19.
Langmuir-Blodgett films of lithium salts of 10,12-nonacosadiynoic acid monomer (Li/16-8 DA) and polymer (Li/16-8 PDA) were characterized by scanning force microscopy (SFM or AFM) to study their surface molecular structure. Based on analysis of these images, a two-dimensional oblique unit mesh is assigned for Li/16-8 DA monomer LB film with unit mesh parameter c = 0.549 ± 0.040 nm and b = 0.541 ± 0.060 nm with an angle of 113°. A hexagonal unit mesh is assigned for Li/16-8 PDA with unit mesh parameter c = 0.497 ± 0.052 nm and b = 0.497 ± 0.060 nm. We then report the comparison of two-dimensional, fast Fourier transform (FFT) of SFM images to the electron diffraction images. From the viewpoint of a three-dimensional structure projected onto a plane, centered rectangular nets can be assigned for both Li/16-8 DA and Li/16-8 PDA. The monomer unit cell parameters are c = 0.460 ± 0.040 nm and b = 1.020 ± 0.060 nm. The polymer cell parameters are c = 0.485 ± 0.080 nm and b = 0.820 ± 0.010 nm. The correlation between the two very different methods of surface structure determination is excellent. However, care must be taken in assigning the unit net (two-dimensional representation) and the projected unit cell (three-dimensional) vectors.  相似文献   

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