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1.
化学镀非晶态镍磷和镍钨磷双层组合镀层工艺研究   总被引:3,自引:0,他引:3  
本文着重研究非晶态Ni-P和Ni-W-P双层组合镀层的化学镀工艺条件:如镀液组分及PH值等对镀层在分,镀层沉积速率的影响。实验结果表明;在苹果酸体系中化学镀镍磷镀层比较合适的艺条件为;硫酸镍0.1mol/L,次磷酸钠0.25mol/L、苹果酸0.20mol/L,琥珀酸0.15mol/l,pH=4.5-5.0温度为90℃。  相似文献   

2.
无电解镀镍磷非晶态合金的近边结构研究   总被引:2,自引:1,他引:2  
用DTA,XRD和EXAFS方法研究无电解镀镍磷合金层结构,其中含P10%(重量百分比)左右的Ni-P合金层是非晶态合金固溶体,Ni,P之间存在共价键作用,Ni-Ni键长0.25nm,Ni-P键长0.28nm经400℃热处理1后的含P10%的Ni-P镀层是Ni3P晶态与Ni-P非晶态的混合物,EXAFS方法给出了镍磷合金层的结构,键长和配位原子情况,体现出EXAFS方法在研究金属结构尤其是非晶态金  相似文献   

3.
电沉积Ni—Mo—P合金镀层在NaCl溶液中的腐蚀特性   总被引:1,自引:0,他引:1  
曾跃  姚素薇 《电化学》1998,4(4):380-387
用失重法,阳极率曲线,X-光电子能谱(XPS)以及俄歇电子能谱(AES)研究了电沉积Ni-Mo-P合金镀层在5%NaCl溶液中的腐蚀特性,非晶态Ni-Mo-P合金镀层比晶态Ni-Mo-P合金镀层有较低的腐蚀速度阳极极化曲线表明,Ni-Mo-P合金镀层中,镍的摩尔分数国0.719~0.868时,随镀层中磷含量的增加,腐蚀电位正移,而活化区的峰电流随镀层中钼含量的增加而增加,磷含量的活化区的峰电流以及  相似文献   

4.
Ni—La2O3复合镀层的氧化行为及机制   总被引:4,自引:1,他引:4  
通过对金属镍、镍镀层及Ni-La2O3复合镀层于900℃、1000℃时的恒温氧化实验,发现Ni-La2O3复合镀层的氧化行为明显改善。高分辨电子显微镜(HREM)的观测研究表明,Ni-La2O3复合镀层氧化时,纳米尺寸的La2O3颗粒掺入到氧化层中,形成了NiO-La2O3复合氧化物层;在氧化层晶界发现了异常原子排列的新现象。由此认为,Ni-La2O3复合镀层抗高温氧化性能的提高,主要归因于小尺寸  相似文献   

5.
半导体硅上电沉积Ni-Pd-P薄膜及其结构   总被引:1,自引:0,他引:1  
刘泳  姚素薇 《应用化学》1999,16(1):16-20
采用控电位的沉积方式在半导体硅上制备出NiPdP薄膜,结果表明镀液中H3PO3含量的增加对P、Ni的析出有促进作用,对Pd的析出有抑制作用.随pH值的升高,镍含量不断升高,Pd、P含量不断下降.P含量对薄膜内应力有很大影响,含P质量分数为149%的NiPdP镀层表面上有许多裂缝,当P含量增加到261%时,镀层表面的裂缝已基本消失,继续增加P含量到350%时,裂缝完全消失.NiPdP镀层的结构与其组成密切相关,P含量小于200%的NiPdP镀层形成的是面心立方结构的固溶体.P含量大于400%的薄膜为非晶态结构.  相似文献   

6.
研究了新型Ni-P-B超细非晶合金(UFAAP)的制备化学反应。Ni-P-B UFAAP通过在溶液中使用KBH4和NaH2PO2还原NiCl2生成,反应较复杂,涉及6个基本化学方程式。通过临控反应pH随时间的变化,发现总反应分成4个阶段,其中Ⅱ、Ⅲ阶段分别生成Ni-P-B和Ni-B UFAAP。在第Ⅱ阶段收集样品可得Ni-P-B。随着反应物比例n(H2PO2)/n(Ni^2+)的增加,产物中的磷含  相似文献   

7.
通过对金属镍、镍镀层及Nl-La2o3复合愤层于900℃、1000℃时的恒温氧化实验,发现Nl-La2O3复合镀层的氧化行为明显改善。高分辨电子显徽镜(HREM)的观测研究表明,Ni-La2O3复合铰层氧化时,纳米尺寸的ka2O3颗粒掺人到氧化层中,形成了NiO-La2O3复合氧化物层;在氧化层晶界发现了异常原子排列的新现象。由此认为,Ni-La2O3复合镀层抗高温氧化性能的提高,主要归因于小尺寸的纳米颗粒可微量溶解,成为La(3+)的晶界们聚“源”,阻止Ni(2+)的短路向外扩散,从而改善了氧化层的微观结构和生长机制。  相似文献   

8.
芳族硝基化合物电还原中Cu-Ni合金的电极活性   总被引:5,自引:0,他引:5  
马淳安  童少平  陈骁军  黄辉 《电化学》1997,3(4):438-441
本文采用共沉积法制备了以铜为基体的不同Cu/Ni比的Cu-Ni合金镀层,并用稳态极化法研究了这些镀层在使用硝基苯(NB)和1,5-二硝基蒽醌(1.5-DNA)制备对氨基苯酚(PAP)及1,5-二氨基-4,8-二羟基蒽醌(1,5-DA-4,8-DHA)等电化学还原过程中的阴极活性.研究表明,在PAP和1,5-DA-4,8-DHA电合成体系中,不同Cu/Ni比的合金阴极具有不同的交换电流密度(io)和表观活化能(EA),其中以0.05mol/LCuSO4·5H2O+0.6mol/LNiSO4·6H2O+0.25mol/LNa3Cit·2H2O组成的镀液,并在控制电流密度为0.6A·dm-2、pH值为6、体系温度为50℃等工艺条件下镀制的Cu-Ni合金试片(CN-30),具有最大的io和最小的EA值,与常规所用的Cu、Cu/Hg、蒙乃尔合金等阴极相比,CN-30试片的电极性能最佳  相似文献   

9.
应用循环伏安,恒电位阶跃和X射线衍射(XRD)等方法了Ni-W-P合金电沉积特点和镀层结构与显微硬度,结果表明,在以柠檬酸铵为配体的溶液中,Ni-W-P合金 层较Ni-W合金有较低的电化学活性,根据电位阶跃的i-t曲线分析表明,在玻碳电极上Ni-W-P合金电结晶过程遵从扩散控制瞬时成核三维成长模式进行,随着过电位的增加,电极表面上晶核数增多,XRD试验结果表明,Ni-W-P合金镀层呈现明显的非晶态特征,所获得的Ni-W-P合金电沉层的显微硬度在450kg.mm^-2左右。  相似文献   

10.
化学镀非晶态Ni—P层的初期沉积过程研究   总被引:2,自引:0,他引:2  
迟毅  张磊 《电化学》1997,3(4):433-437
化学镀非晶态Ni-P镀层初期沉积过程和沉积层状态是影响结合强度的决定性因素.对不同基体材料初期沉积的观察发现,有些非晶态镀层的初期沉积中含有微晶.微晶的产生与否与基体材料以及镀层材料晶格的错配度有关,当镀层与基体材料点阵常数相差不大,镀层的初期沉积沿基体晶格外延生长出现微晶层,反之,点阵常数相差较大时,初期沉积物中未发现微晶.  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

18.
19.
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).  相似文献   

20.
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.  相似文献   

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