首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 140 毫秒
1.
TiO2纳米粒子膜的制备,表面态性质和光催化活性   总被引:3,自引:0,他引:3  
曹亚安  黄英 《催化学报》1999,20(3):353-355
在酸性和碱性条件下,用TiCl4水解法制备了TiO2纳米粒子膜催化剂。采用原子力显微镜(AFM),X射线衍射(XRD),表面光电压谱(SPS)和场诱导表面光电压谱(EFISPS)测定了催化剂表面的微结构及能级结构。  相似文献   

2.
表面活性剂阴离子双水相新体系及其对卟啉、染料的萃取   总被引:1,自引:0,他引:1  
由阴阳离子型表面活性剂水溶液混合形成的双水相[1,2]是水相分离技术中的一个新分支.ZHAO等[2]将阴阳离子表面活性剂过量的体系分别称为阴阳离子双水相.由溴化十二烷基三乙铵(C12NE)和十二烷基硫酸钠(SDS)组成的阳离子双水相对蛋白质[1]、酶[3]、氨基酸[4]和卟啉[5,6]等的萃取分离已有报道.与阳离子双水相比较,阴离子双水相分相时间慢,其萃取应用研究尚未见报道.本文在详细研究了SDS-C12NE阴离子双水相的基础上,将全氟型阴离子表面活性剂全氟辛酸钠(SPFO)引入这类水相分离体系…  相似文献   

3.
本文由[(μtBuS)(μCO)Fe2(CO)6][Et3NH]和硒粉形成的[(μtBuS)(μSe)Fe2(CO)6][Et3NH],分别与溴化苄,二碘甲烷及邻一、间一、对一双(溴甲基)苯反应,合成了蝶状Fe2SSe单簇物(μtBuS)(μPhCH2Se)Fe2(CO)6(3a)和双簇物[(μtBuS)Fe2(CO)6]2(μSeZSeμ)[Z=CH2,o.m.p双(亚甲基)苯](4ad)。类似地,由[(μPhSe)(μCO)Fe2(CO)6][Et3NH]和硫粉或硒粉所形成的[(μPhSe)(μS)Fe2(CO)6][Et3NH]或[(μPhSe)(μSe)Fe2(CO)6][Et3NH]分别与对一双(溴甲基)苯反应合成了蝶状Fe2SSe和Fe2Se2双簇物[(μPhSe)Fe2(CO)6]2[μS(pCH2C6H4CH2)Sμ](5a)及[(μPhSe)Fe2(CO)6]2[μSe(PCH2C6H4CH2)Seμ](5b)。所有产物均经元素分析、IR和1HNMR表征。  相似文献   

4.
合成了{[(n-Bu)2Sn(4-Fc-C6H4COO)]2O}2(1)和{[n-Oct)2Sn(4-Fc-C6H4COO)]2O}2(2)(Fc=ferroenyl两组新的配合物,对其进行了元素分析,并用IR,NMR(^1H,^13C,^119Sn)进行了谱学表征,单晶X射线衍射法测定表明,配合物1的晶体属单斜晶系,P21/c空间群,晶胞参数a=1.2988(1)nm,b=2.655(1)nm,  相似文献   

5.
通过滴加NaNO3、NaOH、HNO3、H2SO4和HCl对银胶体系及CR(二苯并[b,f][1,4]氧杂吖庚因)SERS(表面增强喇曼散射)信号的影响,探讨滴加酸溶液引起银胶体系中CR瞬即产生SERS的机理。  相似文献   

6.
用离子散射谱(ISS)、俄歇电子能谱(AES)及低能电子衍射(LEED)技术对Ni3Ti(0001)表面结构与组成进行考察后,主要采用高分辨电子能量损失谱(HREELS),以CO为探针分子,研究了清洁及部分氧化的Ni3Ti(0001)表面上Ni,Ti间的相互作用及对CO吸附态的影响.结果表明:(1)在最表层几乎完全为Ni的Ni3Ti(0001)清洁规整表面上,CO没有发生解离;(2)次表层Ti原子与最表层Ni原子间的电子相互作用,使初始吸附的CO伸缩振动与Ni(111)相比向低频位移约60cm-1;(3)适量CO暴露后,CO氧端与近邻Ti原子的成键作用产生了一种新的Nix-C-O-Tiy物种.Ni3Ti(0001)表面部分氧化后,上述(2)和(3)作用消失  相似文献   

7.
三取代钨硅杂多配合物的导电性和磁性   总被引:5,自引:0,他引:5  
合成了α-NamHn[SiW9M3(H2O)3O37]·16H2O(M=Co(Ⅱ),Ni(Ⅱ),V(Ⅴ)杂多配合物),通过ICP,IR,UV,TG-DTA,XPS,EPR,极谱等手段进行了表征.配合物在室温下的电导率σ值达1×10-3S·cm-1,343K时可达1×10-2S·cm-1,是有实用化前景的新型固体电解质.变温磁化率结果表明α-Na10[SiW9Co3(H2O)3O37]·16H2O和α-Na10[SiW9Ni3(H2O)3O37]·16H2O具有反铁磁性.  相似文献   

8.
2-(5-溴-2-吡啶偶氮)-5-二乙氨基苯酚(5-Br-PADAP)在极谱和伏安分析中的应用已有一些报道。陈林林等曾经研究过Ti(Ⅳ)-5-Br-PADAP络合物在稀H2SO4-H2C2O4溶液中的极谱行为,但灵敏度不高(1.0×10-7mol/L)。我们发现,在pH4.1左右的HAc-NaAc底液中,Ti(Ⅳ)-5-Br-PADAP-NaClO3体系产生一灵敏的极谱吸附催化波,二次导数峰电位在-0.86V(vs.SCE)左右,波形良好,波高稳定,检测限可达4×10-10mol/L。1 实验部…  相似文献   

9.
光催化与光化学联合降解苯胺   总被引:8,自引:0,他引:8  
水中许多难于被其它方法降解的有机污染物(例如卤代烃、表面活性剂、多氯联苯、染料等)能在TiO2的光催化作用下发生矿物化的降解反应,被氧化为CO2、H2O等简单的无机物,对环境不会带来二次污染[1~3].近年来有关TiO2纳米晶(或微晶)膜的制备与光催...  相似文献   

10.
合成了3种以4,4’-联吡啶为配体的三核环状Cu(Ⅱ)配合物[Cu3(4,4'-bpy)3.(phen)3](ClO4)6.2H2O(1),[Cu3(4,4'-bpy),(bpy)3](ClO4)6.H2O(2)和[Cu394,4'-bpy)3.(NO2-phen)3](ClO4)6.6H2O(3)。经元素分析,电导,IR,电子光谱,ESR,磁化率等方法进行了表征,推定该配合物具有以4,4’-联吡  相似文献   

11.
The low temperature RF plasma treatment was used to control the surface chemistry and optical property of TiO2 thin films deposited by RF magnetron sputtering with a very good uniformity at 300 °C substrate heating temperature. The XRD pattern indicates the crystalline structure of the film could be associated to amorphous structure of TiO2 in thin film. The plasma treatment of TiO2 film can increase the proportion of Ti3+ in Ti2p and decrease in carbon atoms as alcohol/ether group in C1s at the surface. The optical transmittance of the film was enhanced by 50% after the plasma treatment. The surface structure and morphology remain the same for untreated and low-pressure plasma-treated films. Therefore, increase in the optical transmission could be due to change in surface chemistry and surface cleaning by plasma treatment.  相似文献   

12.
Ar/O2低温等离子体处理的高密度聚乙烯(HDPE)膜,和硅烷化玻璃进行粘接。借助X光电子能谱仪(XPS)和衰减全反射红外光谱(ATP-FTIR)对Ar/O2等离子体处理的HDPE膜和硅烷化玻璃进行表面结构分析。研究不同等离子体处理时间、成层温度和成层时间对HDPE/APS-玻璃粘接效果的影响,考察HDPE膜的亲水性与其粘接性之间的关系,寻找HDPE/APS-玻璃最佳粘接条件。结果表明,在本实验条件下,实现了HDPE膜与玻璃之间的粘接,HDPE/APS-玻璃剥离粘接强度高达51.2N/cm。  相似文献   

13.
TiO2在Al2O3表面上分散状态的AEM研究   总被引:12,自引:0,他引:12  
魏昭彬  辛勤  Sham  E.L.  Grange  P.  Delmon  B. 《物理化学学报》1990,6(4):474-479
本文运用AEM方法考察了制备技术对TiO_2在Al_2O_3表面分散状态的影响. 发现嫁接法可使TiO_2非常均匀地分散在Al_2O_3表面上, 浸渍法也能得到较为均匀的TiO_2分布, 而沉淀法所得到的TiO_2分散度较差. TiO_3只聚集在Al_20_3表面上的局部区域。  相似文献   

14.
含二氮杂萘酮结构聚醚砜酮膜的微波等离子体处理研究   总被引:4,自引:0,他引:4  
含二氮杂萘酮结构型聚醚砜酮(PPESK)是近年来本研究组开发成功的新型耐高温聚合物[1].该聚合物具有优异的力学性能和突出的耐热性,玻璃化转变温度(Tg)为265~305℃(随砜酮比不同而变化),其结构式如下:ONNOSOOONNOCO  研究表明,用PPESK制成的气体分离膜对O2/N2、CO2/N2有良好的气体渗透性和透过选择性[2,3],但由于其亲水性不高进而限制了它在纳滤膜和反渗透膜等方面的应用,因此有必要对其进行改性.目前,常用的膜及膜材料改性的方法有磺化、氯甲基化季胺化、接枝等化学改性和低温等离子体与辐射等物理改性.其…  相似文献   

15.
Polyacrylamide (PAL) was physically adsorbed onto a hydroxylated silicon surface to form a uniform PAL film and the up-top PAL thin film was treated by nitrogen (N2) plasma for surface modification. The atomic composition of the modified surface of the PAL film adsorbed on silicon substrate was analyzed with Fourier Transform Infrared Spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The surface energy of PAL film was calculated from the data of contact angle of three-probe liquid. The FTIR results show an increase of peak intensity at 1214 cm−1 (NH2 stretch vibration) after the nitrogen plasma treatment, which confirms that the nitrogen was grafted to the PAL surface in the process of N2-plasma treatment. The XPS results show that the ratio of relative intensity of N1s to O1s increases with increasing the plasma treatment time, which further affirms the formation of the amine groups on the PAL surface after the nitrogen plasma treatment. The surface tension increases with increasing the plasma grafting time. However, the surface energy decreases rapidly at the early stage when stored in air and approaches to an equilibrium value. It suggests that some physically-adsorbed ions and alkyl radicals on PAL surface can rapidly lose their activities. The increase of the surface tension of the plasma treated PLA films is due to the amine groups covalently grafted to PAL surface.  相似文献   

16.
MgCl_2负载TiCl_4催化剂中内给电子体对活性组分钛的影响   总被引:2,自引:0,他引:2  
应用XPSI、R等表征手段研究了以MgCl2为载体,苯甲酸酯、邻苯二甲酸酯以及1,3-二醚为内给电子体的Ziegler_Natta(Z-N)催化剂中内给电子体对活性组分Ti的作用.实验结果表明,不同内给电子体Z-N催化剂中Ti的氧化状态是不同的,给电子体不与Ti直接发生作用,而是通过MgCl2为媒介向Ti发生电荷转移,造成Ti周围电子云密度增大,Ti的氧化状态降低,表现为Ti的结合能下降.  相似文献   

17.
MoO3在Al2O3薄膜表面扩散的研究   总被引:3,自引:0,他引:3  
氧化物和盐类在高比表面载体上的单层分散现象已被大量实验所证实[1].MoO_3在γ-Al_2O_3等高比表面载体上的分散已经研究很多,近来的研究证实MoO3等在α-Al2O3等小比表面载体上也能自发单层分散[2],但是分散的过程仍然缺乏直接的观察研究.本工作通过多种表面分析方法首次研究了MoO3在平整无定形的Al2O3薄膜上的扩散过程以及影响因素.发现除温度升高外、水汽的存在对该扩散过程也有促进作用.1实验部分1.1样品的制备采用SS-3200真空磁控溅射镀膜机,通入Ar-O2作为反应气,直流磁控…  相似文献   

18.
The supported catalysts for propylene polymerization were prepared by milling Mg (OEt)_2 with EB (ethylbenzoate) and treating with TiCl_4 solution. When TiCl_4/(Mg(OEt)_2/EB) (mol.) ratio was increased, decrease in contents of-OEt and Ti of the catalysts was observed, while the content of EB increased. It is proved by analyses of IR, X-ray and XPS that during co-milling Mg(OEt)_2 with EB no reactions have taken place. But after treatment with TiCl_4 solution, Mg(OEt)_2 converts into MgCl_2 and EB coordinates on the resulting MgCl_2 carrier, a surface complex forms.The activity of catalysts,isotacticity and vicosimetric molecular weight of polypropylene increase with the decrease of the content of ethoxyl group. The kinetic curves of propene polymerization obtained with present catalysts system display decay curves. It is found from the triad tacticity calculated from the expanded spectra of methyl carbon region that, ethoxyl group in catalyst has an effect on the configuration of polymer chain.  相似文献   

19.
乙烯等离子体处理的云母表面结构及表面性质   总被引:5,自引:0,他引:5  
用元素分析、色-质谱、裂解气相色谱和顺磁共振等方法研究了经乙烯等离子体处理的云母表面化学结构及处理过程。结果表明,云母颗粒表面形成了厚数十埃的等离子体聚乙烯膜,其化学结构与反应体系中无云母时得到的等离子体聚乙烯膜相同。通过扫描电镜观察到云母片表面的聚合膜具有规则的海星状花样,随处理时间的延长花样按比例长大。水与云母表面的接触角数据说明,乙烯等离子体处理使云母表面的疏水性提高到聚乙烯的水平,比氩气等离子体、硅烷偶联剂及钛酸酯偶联剂处理的效果均更为显著。  相似文献   

20.
Composites with titanium oxide structures on the surface of a polymer matrix were prepared by preliminary plasma activation of polytetrafluoroethylene films, followed by chemical treatment with vapors of titanium tetrachloride and water. The chemical composition and structure of the modified film surface were studied by scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. The stability of the formed surface charge increases in going from the initial film to the plasma-activated film, then to the film successively treated with vapors of titanium tetrachloride and water, and finally to the plasma-activated film treated subsequently with vapors of titanium tetrachloride and water. The modified polytetrafluoroethylene films are of interest as electrets with enhanced operation characteristics.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号