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1.
本文报道了采用固体稀释处理后,以摄谱法成功地分析了新型复合电触头材料粉体Ag80(WC70TiC30)17C3中主成份银、钨、钛的含量,其相对差为0.26%,摄谱法本身的标准偏差为0.294。文中还对赋于对试样进行固体稀释处理而可能引入的误差,进行了计算机模拟分析。  相似文献   

2.
对担子菌LMPQ39菌丝原生质体进行了紫外光──LiCl复合处理后,得到突变株U39,再将其分别用60Co、HNO2两种方法处理,各获得突变株UCo39和UN39,它们的CMC酶活由原来LMPQ39的0.31u分别提高到0.46u和0.576u.酯酶同功酶电泳表明,UCo39、UN39和母株LMPQ39的酶谱出现了6条共同的谱带,同时也出现差异.突变株和母株的拮抗试验呈阳性。  相似文献   

3.
用极谱法对「Cu(Ⅱ)」-氨基酸配合物体系的极谱行为进行研究,在u-0.1(NaClo4)、T=298K,pH=7.00的条件,发现电极还原为扩散控制的可逆过程。  相似文献   

4.
溶胶法制备粒状合金固体Fe0.10Co0.0.5—(SiO2)0.85…   总被引:1,自引:0,他引:1  
首闪用溶胶法制备了Fe0.10Co0.05-(SiO2)0.85粒状合金固体。这种粒状合金固体是一种纳米复合材料,由嵌在SiO2母体中的Fe-Co合金颗粒构成。本文报告这种材料的基本制备方法以及还原温度对其磁学性质的影响。  相似文献   

5.
用直接合成法制备了Laβ-Al2O3固体电解质,利用阻抗谱测定了电导率,研究了电导率和温度、MgO含量之间的关系,得出最了的组成为aMg0.4Al10.7O17.95。在450℃到1000℃温度下测得电导率为10^-6到10^-2S.cm^-1,活化能为0.89eV到1.02eV。测定了800C下的离子迁移烽接近于1。  相似文献   

6.
CaCl2法质粒转化最佳条件的探讨   总被引:7,自引:0,他引:7  
CaCl2法质粒转化中的一些关键性步骤的实验条件进行了探讨结果表明,CaCl2处理对制备感受志受体菌是至关重要的,CaCl2处理后的受体菌在4℃放置16~24h是必要的.CaCl2处理浓度以0.075mol·L-1最佳.为了得到足够的转化菌落,质粒加入量不应低于0.2μg.  相似文献   

7.
采用固相合成法直接合成CaZr0.9In0.1O3-a用交流阻抗谱技术,在869~1300K温度范围内,空气气氛下测得其电导率为10^-4~10^-2s.cm^-1制得CaZr0.9In0.1O3-a固体电解质管,以含H2的标准气为参比电极,组装成氢浓差电池。Fe含H2标准气│CaZr0.9In0.1O3-a│(H)AlFe并构成氢传感探头,研究其对熔融铝中氢含量的传感特性,实验证明,该传感器响应  相似文献   

8.
利用^1H-^1HCOSY,^13C-^1HCOSY,^13C-^1H远程COSY以及选择性远程DEPT^13CNMR谱,对2,4-二硝基五环[4.3.0.0^2.5,0^3.8.0^4,7]壬烷的^1H和^13NMR谱进行了完全的归属。  相似文献   

9.
在0.8~2.0mol/L硫酸及90℃下,An3+对Ce4+氧化Hg_2~(2+)反应有强烈催化作用。用对氯代苯羟乙酸还原Ce(Ⅳ)中止反应,生成极谱活性物质对氯苯甲醛(EP=-0.83Vvs.SCE)。用固定时间法建立检出限和测定范围分别为0.15ng/mL和0.30~4.5ng/mL金的催化反应-导数示波极谱分析法。矿样中痕量金的测定结果表明该法效果较好。  相似文献   

10.
通过甲苯溶液中对─叔丁基─杯[8]芳烃与C60的反应,合成了它们的1:1络合物.产物经红外光谱、元素分析、X-射线粉末衍射确证.还采用固体13C核磁共振技术研究对─叔丁基─杯[8]芳烃对C60的分子识别.13C魔角固体核磁共振谱清楚地揭示出C60被包结在杯芳烃的疏水空腔中.13C核磁共振静态谱表明被包在空腔中的C60分子于室温时仍在快速旋转.这说明C60分子与对─叔丁基─杯[8]芳烃之间的相互作用非常弱.  相似文献   

11.
以商品单质硅为原料,利用金属辅助化学刻蚀方法结合化学镀方法制备了三维多孔硅/银复合负极材料,采用X射线粉末衍射仪、场发射扫描电镜及比表面与孔隙度分析仪对其组成、结构、比表面积及孔隙率进行研究,随后对其电化学性能进行研究.结果表明,三维多孔硅呈现狭缝型的介孔,平均孔径宽度为12.5 nm,比表面积达到6.083 m2/g...  相似文献   

12.
La2O3对Ni基合金激光熔覆层组织和耐磨性的影响   总被引:9,自引:0,他引:9  
在Ni基自熔合金粉末中添加不同量的La2O3,并利用激光形成熔覆层。利用扫描电镜、X射线能谱仪、X射线衍射仪、显微硬度计和环块摩擦磨损实验机等对激光熔覆层显微组织、化学成分、相结构、显微硬度和摩擦磨损性能进行了研究。结果表明,在激光熔覆层中添加La2O3能细化和净化显微组织;降低基材对熔覆层的稀释率;减小固溶体的晶格常数;提高熔覆层的显微硬度;降低熔覆层摩擦系数并提高其耐磨性能。该文还探讨了La2O3作用的机理。  相似文献   

13.
新型复合电接触材料的开发研究   总被引:16,自引:0,他引:16  
报导了一种新型电 研究开发成果。在目前普遍使用的银碳化钨-石墨体接触材料的基础上,添加适量的碳化钛,并采用化学包覆技术在添加物粉体的表面全量镀银制成Ag80(WC70TiC30)17C3(重量百分比)复合粉末,经粉末冶金工艺制成新型复合电接触材料。测试表明,该材料具有较好的综合性能,并较原有的银基复合电接触材料节银达5%。该材料已制成元件装配在开关上,并通过了开关试验,表明该材料已具有实用价值。  相似文献   

14.
采用X射线光电子谱对Ag-La_2O_3复合镀层进行了分析。结果表明,微粒在镀层中不是简单的机械夹杂,而是在接触界面处与周围的Ag原子发生化学作用,形成Ag、La、O非计量界面扩散反应层。文中讨论了荷负电徽粒的复合电沉积机理,以“微粒效应”和“电蚀中心”的观点解释Ag-La_2O_3复合镀电触点耐电蚀现象。  相似文献   

15.
The rectangular microtubes array of perchlorinated copper phthalocyanines(G16CuPc),were synthesized by physical vapor deposition technique without using any template or catalyst.The synthesis process of the tubular structure is very simple,easy to control,and a little raw material is used.The morphology and crystal structure of the obtained samples were analyzed by means of scanning and transmission electron microscopy(SEM and TEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR) and X-ray photoelectron spectroscopy(XPS).The microtubes have an entire hollow interior,open ends with rectangular cross-section,a large interior of 1.4-1.8 urn width,and the thin walls of 80-100 nm.The obtained products exhibit excellent crystalline nature,high chemical and thermodynamic stability,excellent biocompatibility,as well as innocuity.It is believed that these well-defined microtubular structures of an organic material will be used as active materials for solar cells,nanodevices for field emission apparatus,microchannels for biochip and microvessel for drug delivery.  相似文献   

16.
本文研究磷苯妥英钠七水化合物合成的方法.通过化学合成的方法以苯妥英为起始原料,经羟甲基化、氯化、缩合、氢化、成盐制得磷苯妥英钠七水合物.其中,缩合一步所用二苄基磷酸银,是以苄醇为起始原料,经三步反应制得.经过八步合成反应和一步精制得到最终产物.该生产工艺稳定,其反应路线为一条较为理想的合成工艺路线.  相似文献   

17.
在M2高速钢表面磁控溅射制备Cr-N耐磨减摩涂层,用SEM观察涂层组织,采用XPS及GDOES分析涂层表面价态及主要元素分布情况,利用附带电化学噪声装置的微动摩擦学试验机测试涂层及基材在0.02mol/LNa3PO4溶液环境下的摩擦学性能及其同步电化学噪声变化规律,并与涂层及基材在干摩擦条件下的摩擦学性能指标进行对比.研究结果表明:涂层为双层及双组分结构,组成相为Cr+CrN:涂层在空气介质中表现出优异的耐磨减摩特性,但在Na3PO4水溶液环境下介质中,由于涂层接触区域的去钝化/再钝化以及界面点蚀使腐蚀和磨损相互加速,导致Cr-N涂层丧失了减摩及抗磨作用,失效行为完全不同于干摩擦条件.  相似文献   

18.
Investigation of the Ce-Mn conversion coating on 6063 aluminium alloy   总被引:1,自引:0,他引:1  
In this paper, the sustainable Ce-Mn chemical conversion coating was fabricated on 6063 aluminium alloy by means of Ce(NO3)3 and KMnO4 as the inhibitors and NaF as the accelerator. The morphologies, composition and valence state of the coating were analyzed by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray photoelectron spectroscopy (XPS), respectively. The results indicated that the Ce-Mn conversion coating was formed. The anticorrosion of the coating was evaluated in 3.5 wt.% NaCl aqueous solution at room temperature by using polarization curve and electrochemical impedance spectroscopy (EIS). It indicated that the treated surface presented better anticorrosion behavior in chloride media than on the original material surface. The corrosion resistance of Ce-Mn conversion coating was about equal to the trivalent chromium conversion coating.  相似文献   

19.
The early corrosion control of biomedical magnesium alloy is an important measure to determine its good performance during implantation into human body. The deposition of calcium phosphate biological coating is the most effective solution at present. In this paper, hydroxyapatite (HAP) coating was hydrothermal synthesized on the surface of AZ31B magnesium alloy, and the influence mechanism of hydrothermal synthesis temperature, time and solution concentration was investigated. The synthesis conditions and deposition mechanism of hydroxyapatite coating without DCPA (CaHPO4) were proposed. The surface morphology of the coating was observed by field emission electron scanning microscope (FESEM). The types and contents of microelements in the material were analyzed by energy disperse spectroscopy (EDS). Fourier transform infrared spectroscopy (FTIR) was used to analyze the functional group information of the coating surface. The corrosion resistance of different experimental groups was studied by electrochemical test. The results showed that when the calcium phosphate solution concentration was 0.1 ?mol/L and the calcium/phosphorus ratio was 1.67, the coating had better morphology structure and corrosion resistance, and the calcium/phosphorus ratio of HAP crystals reached 1.58, the epit of the prepared AZ31B-HAP coating by bare metal increased from ?1.51 ?V to ?1.18 ?V, the impedance value reached 1.0 ?× ?105 ?Ω?cm2, and the early corrosion of magnesium alloy substrate was effectively delayed.  相似文献   

20.
An in vitro feasibility study of the use of poly(ethylene carbonate) (PEC) as a biodegradable coating material for drug-eluting stents is reported, and the performance of PEC is compared with that of poly(lactic-co-glycolic acid) (PLGA). Scanning electron microscopy (SEM) images of PEC and PLGA discs after treatment with an alkaline KO2 solution as a superoxide source showed that the PEC maintained its integrity whereas holes and small particles appeared during the treatment of PLGA. Sirolimus and paclitaxel were loaded into PEC and PLGA in order to study drug release performance. Attenuated total reflectance–infrared (ATR– FTIR) spectroscopy of sirolimus, PEC and the sirolimus-loaded PEC coating showed that no chemical reaction occurred between sirolimus and PEC. The results of atomic force microscopy (AFM) revealed that the mean roughness (Ra) values of the bare metal stent (BMS) and the drugeluting stent (DES) were 2.3 nm and 1.0 nm, respectively. After balloon expansion experiments, no delamination or destruction of the PEC coating was observed. The drug release profile of sirolimus was different from that of paclitaxel when PEC was employed as the drug carrier, and the release curves of sirolimus were different when PEC and PLGA were used as drug carriers. All the experimental results demonstrated that PEC was one of the best potential stent-coating materials.  相似文献   

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