The haemocompatibility of Ti-3Zr-2Sn-3Mo-25Nb biomedical alloy was studied after surface heparinization. A layer of sol-gel TiO2 films was applied on the alloy samples followed by active treatment in the bio-functiona...The haemocompatibility of Ti-3Zr-2Sn-3Mo-25Nb biomedical alloy was studied after surface heparinization. A layer of sol-gel TiO2 films was applied on the alloy samples followed by active treatment in the bio-functionalized solution for introducing the OH- and groups, and then the heparin was immobilized on the active TiO2 films through the electrostatic self assembly technology. It is shown that the heparinized films are mainly composed of anatase and rutile with smooth and dense surface. In vitro blood compatibility was evaluated by haemolysis test, clotting time and platelet adhesion behavior tests. The results show that the haemocompatibility of the alloy could be significantly improved by surface heparinization.展开更多
Electrostatic self-assembly method （ESAM） was used to prepare bentonite supported-nano titanium dioxide photocatalysts. The materials were characterized by X-ray diffraction （XRD）, fourier transform infrared spect...Electrostatic self-assembly method （ESAM） was used to prepare bentonite supported-nano titanium dioxide photocatalysts. The materials were characterized by X-ray diffraction （XRD）, fourier transform infrared spectroscopy （FT-IR） and scanning electron microscopy （SEM）. Methyl orange was used to estimate the photocatalytic activity of the materials. The effects of the calcination temperature and silane dosage on the photocatalytic activity of the samples were investigated. The experimental results show that the bentonite facilitates the formation of anatase and restrains the transformation of anatase to rutile. Part of nano-size TiO2 particles insert into the galleries of bentonite. The photocatalysts exhibit a synergistic effect of adsorption and photocatalysis on methyl orange. Photocatalysts prepared by ESAM method exhibit higher photocatalytic activity and better recycle ability than those of the traditional method.展开更多
Anionic surfactant sodium lauryl sulfate(SDS), cationic surfactant palmityl trimethyl ammonium chloride(CTAC) and TiO_2 were used to prepare multilayer films on quartz optic fibers by the electrostatic self-assembly (...Anionic surfactant sodium lauryl sulfate(SDS), cationic surfactant palmityl trimethyl ammonium chloride(CTAC) and TiO_2 were used to prepare multilayer films on quartz optic fibers by the electrostatic self-assembly (ESA) method. The whole self-assemble process, the function of surfactant and the effect of TiO_2 slurry′s concentration to the self-assemble were discussed. The isoelectric point of TiO_2 slurry measured by experiment is 6.8. The results show that whatever the concentration of the TiO_2 dispersion, a flat and compact adsorbed monolayer on the optic fiber can be built in a stable dispersion at lower pH. There is a adsorbed equilibrium on the substrate (fiber)/solution interface when enough time of incubation is given. A rough and loosen adsorbed layer is formed on the fiber surface by immersed the substrate in a high pH dispersion (pH>10) because the presence of hydroxyl on particle surface. Film thickness can be controlled by controlling the number of layers in the film.展开更多
Gold colloids were prepared by citrate-induced reduction of hydrogen tetrachloroaurale, and gold nanoparticles were electrostatically self-assembled with poly( diallyldimethylammonium chloride) into multi-layer thin f...Gold colloids were prepared by citrate-induced reduction of hydrogen tetrachloroaurale, and gold nanoparticles were electrostatically self-assembled with poly( diallyldimethylammonium chloride) into multi-layer thin films on si/icon and quartz substrates. The paniculate thin films were characterized by UV-vis spea-troscopy, surface, enhanced Raman scattering, atomic force microscopy and resistivity measurements. Due to the interparticle coupling between individual gold particles, an obvious collective particle plasmon resonance was ob-served on UV-vis spectra , and the particulate thin films exhibited a strong SERS effect. For multilayer thin films with a high particle coverage on substrates , resistivity of the order of 10-4 Ω·cm was yielded.展开更多
Horseradish peroxidase monolayer was assembled on the surface of PET-CO2 substrate. The reaction kinetics of HRP/PET film and H2O2 in micro reactor was studied using improved spectrophotometer. The relative activity ...Horseradish peroxidase monolayer was assembled on the surface of PET-CO2 substrate. The reaction kinetics of HRP/PET film and H2O2 in micro reactor was studied using improved spectrophotometer. The relative activity of self-assembly HRP/PET film still remains above 80% after storing for 150 days at 4℃. When applied to determination of H2O2 in sample, the recoveries of H2O2 are 96.5%~101.1%.展开更多
The electrostatically self-assembly method is getting strategically important to prepare multilayer thin films. With careful choice of component materials, this method should allow for the preparation of multilayer th...The electrostatically self-assembly method is getting strategically important to prepare multilayer thin films. With careful choice of component materials, this method should allow for the preparation of multilayer thin films with a variety of excellent technological properties. Ti02/PSS multilayer thin films with ordered structure were prepared by electrostatic self-assembly method. UV-Vis-NIR spectrophotometer, X-ray photoelectron spectroscopy (XPS), and atom force microscopy (AFM) were used to characterize the structure and performance of the multilayer films. Because electrostatically self-assembly method allows molecular-level control over the film composition and thickness, this paper studied the responding depth of photocatalytic activity of Ti02 self-assembled films in detail.展开更多
The cooperative electrostatic attraction and π-π aromatic stacking interactions between tetrahedral tetrapyridinium TP and three tetraanionic tetraphenylethylene derivatives TPE-1～3 led to the formation of a new ki...The cooperative electrostatic attraction and π-π aromatic stacking interactions between tetrahedral tetrapyridinium TP and three tetraanionic tetraphenylethylene derivatives TPE-1～3 led to the formation of a new kind of supramolecular polymer networks in water, which have been confirmed by^1 H NMR,fluorescence, isothermal titration calorimetric(ITC) and dynamic light scattering(DLS) experiments. ITC studies show that the contributions of enthalpy and entropy were comparable, reflecting the importance of hydrophobicity in driving the intermolecular aromatic stacking. DLS experiments indicate that the linear supramolecular polymers formed by these tetratopic monomers further aggregated into networks of 10~2-nm size.展开更多
以聚乙烯吡咯烷酮(PVP)和聚丙烯腈(PAN)的混合液为纺丝液,利用静电纺丝技术制备PVP-PAN纳米纤维膜片,经过预氧化、碳化过程,获得自支撑碳片(PVP-PCNFs)。SEM图像及BET测试结果表明碳片中纳米纤维整体保持完整性,因碳化过程中部分PVP提...以聚乙烯吡咯烷酮(PVP)和聚丙烯腈(PAN)的混合液为纺丝液,利用静电纺丝技术制备PVP-PAN纳米纤维膜片,经过预氧化、碳化过程,获得自支撑碳片(PVP-PCNFs)。SEM图像及BET测试结果表明碳片中纳米纤维整体保持完整性,因碳化过程中部分PVP提前分解而在纤维内部及表面产生缺陷,比表面积增大;XPS结果表明碳片中氧元素及吡咯氮的相对含量相较于PVP改性前有显著增加。电化学测试结果表明该自支撑碳片作为电极表现出较好的2e-ORR催化性能,旋转圆盘电极(RRDE)测试结果表明在0.687 V RHE处2e-ORR选择性为72.6%;恒电位0.5 V RHE电解产生过氧化氢法拉第效率为80.5%,且催化性能在15000 s电解时间内保持稳定。利用静电纺丝技术制备自支撑电极作为氧还原法生成过氧化氢的阴极,有望大幅缩短电化学法生成过氧化氢技术的实用化进程。展开更多
Thiol-capping of CdTe nanocrystals were prepared in aqueous solution. The emission wavelengths of CdTe nanocrystals could be tuned by the refluxing time. Bioinorganic conjugates between CdTe nanocrystals and BSA were ...Thiol-capping of CdTe nanocrystals were prepared in aqueous solution. The emission wavelengths of CdTe nanocrystals could be tuned by the refluxing time. Bioinorganic conjugates between CdTe nanocrystals and BSA were formed via electrostatic/coordinate self-assembly. The photoluminescence intensity of the bioinorganic conjugates was improved obviously. BSA could stabilize the CdTe nanocrystals, and the bioinorganic conjugates at room temperature were stable for a long time. We also demonstrated that CdTe nanocrystals could be blocked with BSA and avoid the nonspecific adsorption.展开更多
An ultrathin film with forth generation poly(aminoamine)(PAMAM) dendrimers (methyl quaternary ammonium salt) as polycation and poly(sodium \%p\% styrenesulfonate) (PSS) as polyainon was fabricated \%via\% sequential d...An ultrathin film with forth generation poly(aminoamine)(PAMAM) dendrimers (methyl quaternary ammonium salt) as polycation and poly(sodium \%p\% styrenesulfonate) (PSS) as polyainon was fabricated \%via\% sequential deposition. It shows that the step by step depositions carried out smoothly by monitoring with UV Vis spectrometer. The multilayer film is rather flat with a mean roughness of \{0.39 nm\} determined by AFM. The average thickness of a bilayer is \{5.0 nm\} obtained from XRD, which indicates that the dendrimers molecules were compressed and possess high flattening.展开更多
基金Project (31100693/C100302) supported by the National Natural Science Foundation of ChinaProject (31011120049) supported by the Australia-China Special Fund, International Science Linkages Program co-supported by the Department of Innovation, Industry, Science and Research of Australia, and the Ministry of Science and Technology and National Science Foundation of China+1 种基金Project(2010ZDKG-96) supported by the Major Subject of "13115" Programs of Shaan’xi Province, ChinaProject (2012CB619102) supported by the National Basic Research Program of China
文摘The haemocompatibility of Ti-3Zr-2Sn-3Mo-25Nb biomedical alloy was studied after surface heparinization. A layer of sol-gel TiO2 films was applied on the alloy samples followed by active treatment in the bio-functionalized solution for introducing the OH- and groups, and then the heparin was immobilized on the active TiO2 films through the electrostatic self assembly technology. It is shown that the heparinized films are mainly composed of anatase and rutile with smooth and dense surface. In vitro blood compatibility was evaluated by haemolysis test, clotting time and platelet adhesion behavior tests. The results show that the haemocompatibility of the alloy could be significantly improved by surface heparinization.
基金Funded by the Natural Science Foundation of Hebei Province, China (No. E2008000537)the Foundation for Development of Science and Technology of Hebei Province, China (No. 07215156)the Open Research Foundation of Key Laboratory of Advanced Civil Engineering Materials (Tongji University),Ministry of Education, China (No. 2010412)
文摘Electrostatic self-assembly method （ESAM） was used to prepare bentonite supported-nano titanium dioxide photocatalysts. The materials were characterized by X-ray diffraction （XRD）, fourier transform infrared spectroscopy （FT-IR） and scanning electron microscopy （SEM）. Methyl orange was used to estimate the photocatalytic activity of the materials. The effects of the calcination temperature and silane dosage on the photocatalytic activity of the samples were investigated. The experimental results show that the bentonite facilitates the formation of anatase and restrains the transformation of anatase to rutile. Part of nano-size TiO2 particles insert into the galleries of bentonite. The photocatalysts exhibit a synergistic effect of adsorption and photocatalysis on methyl orange. Photocatalysts prepared by ESAM method exhibit higher photocatalytic activity and better recycle ability than those of the traditional method.
文摘Anionic surfactant sodium lauryl sulfate(SDS), cationic surfactant palmityl trimethyl ammonium chloride(CTAC) and TiO_2 were used to prepare multilayer films on quartz optic fibers by the electrostatic self-assembly (ESA) method. The whole self-assemble process, the function of surfactant and the effect of TiO_2 slurry′s concentration to the self-assemble were discussed. The isoelectric point of TiO_2 slurry measured by experiment is 6.8. The results show that whatever the concentration of the TiO_2 dispersion, a flat and compact adsorbed monolayer on the optic fiber can be built in a stable dispersion at lower pH. There is a adsorbed equilibrium on the substrate (fiber)/solution interface when enough time of incubation is given. A rough and loosen adsorbed layer is formed on the fiber surface by immersed the substrate in a high pH dispersion (pH>10) because the presence of hydroxyl on particle surface. Film thickness can be controlled by controlling the number of layers in the film.
基金This research was financially supported by China Scholar-ship Council and the Natural Science Foundation of Hubei Province (Project 2000J002)
文摘Gold colloids were prepared by citrate-induced reduction of hydrogen tetrachloroaurale, and gold nanoparticles were electrostatically self-assembled with poly( diallyldimethylammonium chloride) into multi-layer thin films on si/icon and quartz substrates. The paniculate thin films were characterized by UV-vis spea-troscopy, surface, enhanced Raman scattering, atomic force microscopy and resistivity measurements. Due to the interparticle coupling between individual gold particles, an obvious collective particle plasmon resonance was ob-served on UV-vis spectra , and the particulate thin films exhibited a strong SERS effect. For multilayer thin films with a high particle coverage on substrates , resistivity of the order of 10-4 Ω·cm was yielded.
文摘Horseradish peroxidase monolayer was assembled on the surface of PET-CO2 substrate. The reaction kinetics of HRP/PET film and H2O2 in micro reactor was studied using improved spectrophotometer. The relative activity of self-assembly HRP/PET film still remains above 80% after storing for 150 days at 4℃. When applied to determination of H2O2 in sample, the recoveries of H2O2 are 96.5%~101.1%.
基金the National Natural ScienceFoundation of China(No.59982002) Foundation of National Key Lab.of Advanced Metal Materials.
文摘The electrostatically self-assembly method is getting strategically important to prepare multilayer thin films. With careful choice of component materials, this method should allow for the preparation of multilayer thin films with a variety of excellent technological properties. Ti02/PSS multilayer thin films with ordered structure were prepared by electrostatic self-assembly method. UV-Vis-NIR spectrophotometer, X-ray photoelectron spectroscopy (XPS), and atom force microscopy (AFM) were used to characterize the structure and performance of the multilayer films. Because electrostatically self-assembly method allows molecular-level control over the film composition and thickness, this paper studied the responding depth of photocatalytic activity of Ti02 self-assembled films in detail.
基金National Natural Science Foundation of China (Nos. 21432004 and 21472023) for financial support
文摘The cooperative electrostatic attraction and π-π aromatic stacking interactions between tetrahedral tetrapyridinium TP and three tetraanionic tetraphenylethylene derivatives TPE-1～3 led to the formation of a new kind of supramolecular polymer networks in water, which have been confirmed by^1 H NMR,fluorescence, isothermal titration calorimetric(ITC) and dynamic light scattering(DLS) experiments. ITC studies show that the contributions of enthalpy and entropy were comparable, reflecting the importance of hydrophobicity in driving the intermolecular aromatic stacking. DLS experiments indicate that the linear supramolecular polymers formed by these tetratopic monomers further aggregated into networks of 10~2-nm size.
文摘以聚乙烯吡咯烷酮(PVP)和聚丙烯腈(PAN)的混合液为纺丝液,利用静电纺丝技术制备PVP-PAN纳米纤维膜片,经过预氧化、碳化过程,获得自支撑碳片(PVP-PCNFs)。SEM图像及BET测试结果表明碳片中纳米纤维整体保持完整性,因碳化过程中部分PVP提前分解而在纤维内部及表面产生缺陷,比表面积增大;XPS结果表明碳片中氧元素及吡咯氮的相对含量相较于PVP改性前有显著增加。电化学测试结果表明该自支撑碳片作为电极表现出较好的2e-ORR催化性能,旋转圆盘电极(RRDE)测试结果表明在0.687 V RHE处2e-ORR选择性为72.6%;恒电位0.5 V RHE电解产生过氧化氢法拉第效率为80.5%,且催化性能在15000 s电解时间内保持稳定。利用静电纺丝技术制备自支撑电极作为氧还原法生成过氧化氢的阴极,有望大幅缩短电化学法生成过氧化氢技术的实用化进程。
文摘Thiol-capping of CdTe nanocrystals were prepared in aqueous solution. The emission wavelengths of CdTe nanocrystals could be tuned by the refluxing time. Bioinorganic conjugates between CdTe nanocrystals and BSA were formed via electrostatic/coordinate self-assembly. The photoluminescence intensity of the bioinorganic conjugates was improved obviously. BSA could stabilize the CdTe nanocrystals, and the bioinorganic conjugates at room temperature were stable for a long time. We also demonstrated that CdTe nanocrystals could be blocked with BSA and avoid the nonspecific adsorption.
文摘An ultrathin film with forth generation poly(aminoamine)(PAMAM) dendrimers (methyl quaternary ammonium salt) as polycation and poly(sodium \%p\% styrenesulfonate) (PSS) as polyainon was fabricated \%via\% sequential deposition. It shows that the step by step depositions carried out smoothly by monitoring with UV Vis spectrometer. The multilayer film is rather flat with a mean roughness of \{0.39 nm\} determined by AFM. The average thickness of a bilayer is \{5.0 nm\} obtained from XRD, which indicates that the dendrimers molecules were compressed and possess high flattening.
