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1.
研究了在泡沫镍基体上电沉积锡-钴合金镀层的工艺方法,分析了电沉积工艺参数对锡-钴合金镀层性能的影响,并对工艺进行了优化.研究表明:采用该优化工艺所制得的锡-钴合金能提高锂离子电池的容量、稳定性和循环性能.  相似文献   

2.
通过线性扫描伏安法研究了焦磷酸盐溶液体系中铜电极上电沉积锡镍合金的电化学行为,分析了各种镀液成分对电沉积锡镍合金的阴极过程与沉积层组成及表面形貌的影响。结果表明,焦磷酸钾作为主配位剂起配位金属离子,增大阴极极化的作用;辅助配位剂柠檬酸钠的加入可扩大光亮区的电流密度范围,促进锡镍共沉积;添加剂氯化铵使金属离子析出电位正移,对镍具有明显的去极化作用,有利于金属共沉积;糖精钠(光亮剂)对金属离子的析出具有均匀阻化作用。焦磷酸钾、柠檬酸钠和氯化铵添加量的改变会对锡、镍的相对析出速率产生一定的影响,也影响镀层的晶粒尺寸,而糖精钠对锡、镍离子的放电相对速率没有产生大的影响,因此在其使用范围内镀层的组成都较为稳定。  相似文献   

3.
以电沉积方法制备了光亮锡镀层。以正交实验考察了甲磺酸浓度、主盐离子浓度、电流密度、光亮剂等对镀层光亮程度的影响。考察了镀液的的覆盖能力和电流效率。  相似文献   

4.
研究了一种新的甲基磺酸镀锡工艺,利用极化曲线、扫描电子显微镜(SEM)、X射线衍射(XRD)等检测方法分析了添加剂对电沉积过程和镀层微观形貌的影响,阐述了添加剂的作用机理.结果表明:镀液的分散能力为58.98%,覆盖能力为100%;添加剂对锡的电沉积过程能够起到很好的阻化作用,有利于晶核形成,提高镀层质量;镀层在生长过...  相似文献   

5.
由于大量应用各种合成添加剂,实现了酸性光亮镀锡,有关电镀过程及光亮剂的作用机理已有不少研究报导.微分电容测量和其它方法研究表明,光亮剂强烈吸附在电极表面上,阻滞了锡的电沉积过程,使过电位大大增加,以致形成细微、光亮的镀层.光亮剂的作用或许是它们在电极表面上形成吸附膜,使锡离子穿越该膜的速度缓慢,导致电荷传递速度减慢;或者是阻滞沉积过程中某一化学转化步骤,如反应2Sn~+→Sn~(2+)+Sn等,也可导致整个过程的速度减慢、不同的添加  相似文献   

6.
苏梦洋  王利民  李俊  徐杰  陈飚  车飞 《电镀与涂饰》2021,40(17):1322-1327
通过线性扫描伏安法、循环伏安法和计时电流法研究了腰果酚聚氧乙烯醚(BGF)对甲磺酸体系中锡电沉积的影响,并分析了BGF对电镀锡层表面形貌和相结构的影响.结果表明,BGF能够抑制Sn2+的还原反应和传质扩散,改变锡晶粒成核过程,起到细化晶粒的作用,最终得到细致、平整的锡镀层.  相似文献   

7.
专利实例     
电镀锡合金两则 2 0 0 32 0 1 电镀光亮锡 -铜合金电解液提出了一种电镀光亮 Sn- Cu合金电解液。该电解液能在宽广的电流密度范围内形成光亮的锡 -铜合金镀层。镀液中含有一种有机磺酸、二价锡和二价铜的有机磺酸盐 ,一种分散剂和一种光亮剂。(欧洲专利 ) EP1 1 1 1 0 97A1 ( 2 0 0 1 - 0 6- 2 7) 2 0 0 32 0 2 电沉积金 -锡合金发明了一种相当稳定的弱酸性无氰电沉积 Au-Sn合金电解液。该电解液含有金和锡的氯化物作主盐 ;柠檬酸铵为缓冲剂 ;左旋抗坏血酸做稳定剂 ;此外还含有亚硫酸钠。实验结果表明 ,采用该电解液可以获得一系列组成…  相似文献   

8.
AlCl3-EMIC离子液体电沉积光亮Al和Al-Mn镀层   总被引:1,自引:0,他引:1       下载免费PDF全文
通过添加光亮剂, 分别在AlCl3-氯化1-甲基3-乙基咪唑(AlCl3-EMIC)和MnCl2-AlCl3-EMIC离子液体中电沉积Al和Al-Mn镀层, 重点研究了光亮剂对镀层形貌、结构以及光亮性的影响, 探讨了镀层光亮的机理。采用扫描电镜(SEM)和X射线衍射(XRD)对镀层形貌和结构进行观察和分析, 以镀层对图案的反射能力大小对光亮度进行表征。结果表明, 添加光亮剂之后, 可以电沉积出具有镜面光亮的Al和Al-Mn镀层, 并且镀层的光亮度随光亮剂浓度的增加而增加。光亮Al镀层为具有择优取向生长的纳米晶体, 而光亮Al-Mn则是纳米尺寸的非晶颗粒。镀层光亮的产生是由于光亮剂细化了Al晶粒和Al-Mn非晶颗粒, 同时使Al晶体择优取向生长造成的。  相似文献   

9.
为了提高锡电结晶过电位,改善锡镀层表面形貌和制备较好的镀锡电极,通过电镀技术在室温条件下制备了不同电镀液条件下的锡镀层,运用线性伏安法、交流阻抗法和电势阶跃法等电化学方法和SEM技术研究了酸性镀锡体系中明胶对锡沉积的影响。阴极极化曲线和交流阻抗曲线表明,明胶能增大锡沉积反应的电荷传递内阻,提高锡电沉积过电位,延缓锡电沉积反应。电势阶跃表明,锡的电结晶过程遵循扩散控制瞬时成核和三维生长方式的结晶机理。SEM分析结果表明,添加明胶能使锡镀层光滑致密、晶粒细小。电极的极化曲线表明,镀锡电极能提高析氢电位,其中添加明胶所得的锡电极的析氢效果最好。  相似文献   

10.
光亮酸性镀铜添加剂的作用   总被引:2,自引:1,他引:1  
本工作研究光亮酸性镀铜添加剂——2-巯基苯骈咪唑(M)、乙撑硫脲(N)、聚二硫二丙磺酸钠(Sp)和聚乙二醇(P)对铜电沉积过程的作用。实验结果表明:M、P对铜的沉积过程的阻化作用大,可能导致产生细晶粒的镀层;N具有整平效应,而Sp的存在淡N的整平效果更好;若上述四种添加剂在镀液中的含量适宜,则在一定的电流密度范围内铜沉积层呈现光亮,光亮区随N的含量而变,当N达到某一数值时获得光亮镀层的电流密度范围最大,整平能力也最佳。  相似文献   

11.
It is much importance to develop novel multifunctional delivery systems for the combination therapy of drug and gene. In this work, a novel conjugate, polyethylene glycol‐polyethylenimine‐tetrachloroplatinum (IV) (PEG‐PEI‐Pt), with good abilities of antitumor and gene delivery was proposed by combining PEG (Mw 3400 Da), low molecular weight PEI (Mw 800 Da), and tetrachloroplatinum (IV). The antitumoral and gene transfection activities of PEG‐PEI‐Pt were analyzed in many tumor (A549, A375, HepG‐2, HuH‐7, and B16 cells) and normal (COS‐7 cells) cell lines. Similar to cisplatin (one platinum anticancer drug), PEG‐PEI‐Pt showed much higher sensitivity in tumor cells than in normal cells. More importantly, PEG‐PEI‐Pt had a potential to treat drug‐resistant tumors. Almost no transfection efficiency was observed for PEI (Mw 800 Da) and PEG‐PEI. Very interestingly, PEG‐PEI‐Pt could condense plasmid DNA efficiently, and exhibited good transfection efficiency in B16, HepG‐2, A375 and COS‐7 cells, comparable to even higher than PEI 25 kDa. In addition, PEG‐PEI‐Pt could also effectively deliver siRNA into the cytoplasm of tumor cells. With the good antitumoral and gene delivery abilities, PEG‐PEI‐Pt may have a great potential for combination therapy of drug and gene. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

12.
Amphiphilic linear–hyperbranched polymer poly(ethylene glycol)–branched polyethylenimine–poly(?‐caprolactone) (PEG‐PEI‐PCL) was synthesized by progressively conjugating PEG (one chain) and PCL (multi‐chains) to PEI (hyperbranched architecture) with a yield of 87%. PEG‐PEI‐PCL forms nano‐sized uniform spherical micelles by self‐assembly in water. The micelles had an average diameter of 56 nm determined using dynamic light scattering and 35 nm observed from transmission electron microscopy images. PEG‐PEI‐PCL was used as a stabilizer of platinum nanoparticles (PtNPs) for the first time. The particle diameter of PEG‐PEI‐PCL‐stabilized PtNPs was 7.8 ± 1.4 nm. Amphiphilic (hydrophilic–hydrophilic–hydrophobic) and hyperbranched (linear–hyperbranched–grafted) structures enabled PtNPs to effectively stabilize and disperse in liquid‐phase synthesis. The highly disperse PtNPs in PEG‐PEI‐PCL micelles improved the catalytic activity for the reduction of 4‐nitrophenol with a catalytic yield of near 100%. © 2016 Society of Chemical Industry  相似文献   

13.
This study investigated the effect of poly(ethylene glycol) (PEG) additive as a pore-former on the structure formation of membranes and their permeation properties connected with the changes in thermodynamic and kinetic properties in the phase inversion process. The membranes were prepared by using polyetherimide/N-methyl-2-pyrrolidone/PEG (PEI/NMP/PEG) casting solution and water coagulant. The resulting membranes, prepared by changing the ratio of PEG to PEI, were characterized by scanning electron microscope (SEM) observations, measurements of water flux and γ-globin rejection. The thermodynamic and kinetic properties of the membrane-forming system were studied through viscosity. The pore radius distribution curves were especially obtained by differential scanning calorimetry (DSC). Furthermore, the membranes were characterized for pure water flux and rejection of solute and by SEM observation. The filtration results agreed well with the SEM observations. As expected, PEG with a fixed molecular weight (PEG 600) acted as a pore forming agent, and membrane porosity increased as the PEG content of the casting solution increased.  相似文献   

14.
This study investigated the effect of poly (ethylene glycol) (PEG) additive as a pore-former on the structure formation of membranes and their permeation properties connected with the changes in thermodynamic and kinetic properties in the phase inversion process. The membranes were prepared by using polyetherimide/N-methyl-2-pyrrolidone/PEG (PEI/NMP/PEG) casting solution and water coagulant. The resulting membranes, prepared by changing the ratio of PEG to PEI, were characterized by scanning electron microscope (SEM) observations, measurements of water flux and γ-globin rejection. The thermodynamic and kinetic properties of the membrane-forming system were studied through viscosity. The pore radius distribution curves were especially obtained by differential scanning calorimetry (DSC). Furthermore, the membranes were characterized for pure water flux and rejection of solute and by SEM observation. The filtration results agreed well with the SEM observations. As expected, PEG with a fixed molecular weight (PEG 600) acted as a pore forming agent, and membrane porosity increased as the PEG content of the casting solution increased.  相似文献   

15.
Polypiperazine-amide membranes were modified with poly(ethyleneimine) (PEI) by self-assembled method, through which PEI molecules were fixed on the membrane surface by ionic interaction. In the experiments, the PEI concentration ranged from 50 to 2000 mg·L?1 while the depositing time was fixed at 20 min. The results showed that low PEI concentration resulted in a slight increase of pure water flux, which was attributed to the enhanced membrane surface hydrophilicity. The PEI adsorption on membrane surface had less effect on the re-jections to neutral PEG and sucrose, but improved the rejections to divalent cationic ions and methylene blue as the result of reversion of the membrane surface charge from negative to positive according to the XPS analysis and zeta potential measurements. The membrane modified at PEI=1500 mg·L?1 exhibited high rejection to methylene blue (MB) and is potential to be applied in the treatment of effluents containing positively charged dyes.  相似文献   

16.
用浊度法研究了聚合物对烷基苯磺酸钠与钙离子的相互作用的影响,不同聚合物,如聚乙烯亚胺(PEI)、聚乙烯吡咯烷酮(PVP)和聚乙二醇(PEG)在同一pH条件下的研究结果表明,PEI比后两能更好地抑制LAS钙盐的形成。同时一聚合物在不同pH条件下的研究发现,PEI只有在一个适当的pH范围内,即自身具有适当的电荷密度,才能很好地发挥其上述作用。在体系中存在一定量的AEO3条件下,也观察到了PEI在抑制  相似文献   

17.
In this article, we report the surface modification of branched polyethyleneimine (PEI) for improved biocompatibility. PEIs with different surface functionalities were synthesized via covalent modification of the PEI amines, including neutralized PEI modified with acetic anhydride, negatively charged PEI modified with succinic anhydride, hydroxylated PEI modified with glycidol, and PEI–poly(ethylene glycol) (PEG) conjugates modified with both PEG and acetic anhydride. The modified PEI derivatives were characterized with 1H‐NMR, Fourier transform infrared spectroscopy, and ζ‐potential measurements. An in vitro cytotoxicity assay of mouse fibroblasts revealed that the biocompatibility of PEI was significantly improved after these modifications. The neutral and negatively charged PEIs were nontoxic at concentrations up to 200 μg/mL, whereas the pristine PEI was toxic to cells at concentrations as low as 10 μg/mL. The successfully modified PEIs with different surface charges and functionalities may provide a range of opportunities for various biomedical applications. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

18.
Through a dip‐coating technique, carbon membranes were produced from a polymer blend consisting of the thermally stable polymer polyetherimide (PEI) and the thermally labile polymer polyethylene glycol (PEG). The PEG/PEI carbon membranes were synthesized on an alumina support coated with an Al2O3 intermediate layer. The polymer blend ratio and carbonization temperature influenced the structure and permeation performance of the derived carbon membranes. The porosity of the PEG/PEI carbon membranes increased with higher PEG content in the blends. However, the derived carbon membranes tended to lose gas permeability with raising the carbonization temperatures. The carbon membranes were successfully optimized in order to achieve the highest CO2/CH4 and CO2/N2 selectivities.  相似文献   

19.
A targeting gene carrier for cancer‐specific delivery was successfully developed through a “multilayer bricks‐mortar” strategy. The gene carrier was composed of adamantane‐functionalized folic acid (FA‐AD), an adamantane‐functionalized poly(ethylene glycol) derivative (PEG‐AD), and β‐cyclodextrin‐grafted low‐molecular‐weight branched polyethylenimine (PEI‐CD). Carriers produced by two different self‐assembly schemes, involving either precomplexation of the PEI‐CD with the FA‐AD and PEG‐AD before pDNA condensation (Method A) or pDNA condensation with the PEI‐CD prior to addition of the FA‐AD and PEG‐AD to engage host–guest complexation (Method B) were investigated for their ability to compact pDNA into nanoparticles. Cell viability studies show that the material produced by the Method A assembly scheme has lower cytotoxicity than branched PEI 25 kDa (PEI‐25KD) and that the transfection efficiency is maintained. These findings suggest that the gene carrier, based on multivalent host–guest interactions, could be an effective, targeted, and low‐toxicity carrier for delivering nucleic acid to target cells.  相似文献   

20.
介绍了一种新的氯化铵镀锌工艺及光亮剂,讨论了氯化铵镀锌光亮剂、镀液组分、pH值、电流密度、温度、杂质对镀层质量、极化曲线、分散能力和深镀能力的影响,并讨论了氯化铵镀锌的优缺点.  相似文献   

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