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 共查询到19条相似文献,搜索用时 125 毫秒
1.
Surface-modified poly(butadiene)urethane (PBTU) films with silk fibroin (SF) were prepared by simple chemical method under the normal temperature. The physical properties and biological behaviour of the SF-modified PBTU film were evaluated. The results showed that the SF-modified PBTU films kept the tenacity and pliability very well, and could overcome rigid and brittle weaks of silk fibroin films. The morphology of SF in the PBTU film was dendritic aggregations, and the water-contact angle measurement indicated that the surface hydrophilicity of modified films was apparently enhanced. The biocompatibility of PBTU films was improved due to the change of surface components. The degree of platelet adhesion and the cell viability of rat embryo dermal fibroblasts seeded on PBTU films, SF films, and SF-modified PBTU films were measured by counting platelets before and after they contacted the films and MTT assay, respectively. The results indicated that platelet adhesion resistance and cell viability on the modified film were greatly superior to those on the PBTU film and the compound interface had good stability in the air.  相似文献   

2.
Electrospun porous films doped with the green-synthesized CdSe quantum dots were synthesized. Glycerol was chosen to prepare the quantum dots ( QDs), with the highest quantum yield of 78.28%. Polycaprolactone (PCL) was electrospun with CdSe QDs to avoid the QDs' toxicity and improve the QDs' cytocompatibility. The electrospun QDs-doped films preserve the original QDs' fluorescence. Pores can be detected from the SEM of the films, predicting the possibility of loading drugs in the cancer therapy. The cell proliferation assay shows excellent cytocompatibility of the eletrospun CdSe-QDs-doped films. The present eletrospun CdSe- QDs-doped porous films are cytocompatibale, highly-fluorescent and ootential to load drugs in cancer therapy.  相似文献   

3.
A quaternary ammonium compound containing amino acid residue was synthesized by Converting 3-chloro-2-hydroxy-propyalkyldimethylammonium chlorides into its epoxide derivatives, then attaching an amino acid to the epoxide derivatives synthesized a quaternary ammonium compound containing amino acid residue. Modified dyes were prepared by the ionotropy of anionic dyes with the quaternary ammonium compound containing amino acid residue. It was discovered that the modified dyes exhibited an excellent pH controllable solubility. These modified dyes have good water solubility at pH> 8.0, but they were water insoluble at pH < 6.5. On the printing paper, modified dyes in water-based ink-jet print ink could convert to water insoluble form and give prints excellent water fastness.  相似文献   

4.
L10 FePt films were deposited on MgO (001) substrates heated to 700°C by magnetron sputtering.Assisted by the misfit of lattice between film and substrate,strong (001) texture was formed.The film at nominal thickness t N=5 nm was composed of nanoparticles with a size of~70 nm,and showed a high coercivity of~105 kOe at 4.2 K.At t N=~50 nm,as the film changed from discontinuous to continuous,the coercivity dropped about one order of magnitude.Micromagnetic simulation implies that the magnetization reversal is...  相似文献   

5.
A series of TaVN-Ag nanocomposite films were deposited using a radio-frequency magnetron sputtering system. The microstructure, mechanical properties, and tribological performance of the films were investigated. The results showed that TaVN-Ag films were composed of face-centered cubic (fcc) TaVN and fcc-Ag. With increasing Ag content, the hardness of TaVN-Ag composite films first increased and then decreased rapidly. The maximum hardness value was 31.4 GPa. At room temperature, the coefficient of friction (COF) of TaVN-Ag films decreased from 0.76 to 0.60 with increasing Ag content from 0 to 7.93at%. For the TaVN-Ag films with 7.93at% Ag, COF first increased and then decreased rapidly from 0.60 at 25℃ to 0.35 at 600℃, whereas the wear rate of the film increased continuously from 3.91×10-7 to 19.1×10-7 mm3/(N·mm). The COF of the TaVN-Ag film with 7.93at% Ag was lower than that of the TaVN film, and their wear rates showed opposite trends with increasing temperature.  相似文献   

6.
To improve the toughness of silk fibroin( SF) films,poly( ethylene glycol-glycerin)( PEGG) was synthesized with ethylene glycol and epichlorohydrin. The SF / PEGG blend films were prepared by casting aqueous solution and their structures were characterized. The PEGG was in liquid state at room temperature so it will not be a single phrase at blend film. It crosslinked with SF and made it insolubility in water. The results of X-ray diffraction( XRD) indicated that the crystallinity of the SF in the blend films decreased with the content of PEGG increasing. The tensile strength and elongation at break of blend films were measured using an instron tensile tester. The results showed that the tensile strength and elongation at break of blend films were high enough for application.After the blend films were stored at room temperature for 100 d,the crystallinity, the tensile strength and elongation at wet state increased. The blend films are superior to SF films in providing excellent flexibility and mechanical properties in both dry and wet states. Based on the fact that SF has good biocompatibility,the SF /PEGG blend film will offer new options in many different biomedical applications.  相似文献   

7.
The infrared transmission spectra of a 0.54-μm-thick Ge film and a 20-μm-thick Si film were experimentally measured. As the incident radiation was in the wavelength range from 1.5μm to 10μm, the Ge film demonstrated a strongly spectral coherence. However, thermal radiation of the Ge film was found to be spatially incoherent due to its extreme thinness. The Si film exhibited significantly spectral and spatial coherence. The results confirmed that thermal radiation of a monolayer film could be coherent spectrally and spatially if the film thickness was comparable with the wavelength. The optical characteristic matrix method was applied to calculate the transmission spectra of the Si and Ge film, and the results agreed well with the measurements. This method was further used to analyze two multilayer films composed of five low emissive layers. Their emissivities were found to be highly emissive at a certain zenith angle, and the emissive peak could be controlled by careful selection of film thickness.  相似文献   

8.
Unsteady heat conduction is known to deviate significantly from Fourier's law when the system time and length scales are within certain temporal and spatial windows of relaxation. Classical molecular dynamics simulations were used to investigate unsteady heat conduction in argon thin films with a sudden temperature increase or heat flux at one surface to study the non-Fourier heat conduction effects in argon thin films. The studies were conducted with both pure argon films and films with vacancy defects. The temperature profiles in the argon films showed the existence of mechanical waves when the thin film was suddenly heated and the wave nature of the heat propagation. The flux phase relaxation time, Zq, and the temperature phase relaxation time,τt, were calculated from the temporal variations of the energy flux and temperature distribution in the film. Comparisons of the MD temperature profiles with temperature profiles predicted by Fourier's law show that Fourier's law is not able to predict the temperature variations with time. Different film thicknesses were also studied to illustrate the variation of the time needed for the films to reach steady-state temperature profiles after a sudden temperature rise at one surface and to illustrate the finite speed of the energy waves.  相似文献   

9.
Polyaniline (PAn) film was synthesized onto electrode surface modified with a self-assembled monolayer (SAM) of Glutathione (GSH), while copper was deposited in defects of PAn film simultaneously.The resulted PAn films were characterized by means of cyclic voltammetry and electrochemical quartz crystal microbalance (EQCM). The results show that there could be the copper ions‘ route in PAn films, which make easier adulteration of copper ion into the PAn film phase. It was found that the redox peaks of PAn were relevant to the doping of anions and to the adulteration of copper ion.  相似文献   

10.
1 Results In this contribution we present the synthesis and characterization of novel copolymers based on fluorene and thiophene (see Scheme 1).They were synthesized by the Pd-catalyzed Suzuki coupling reaction of 9,9-dihexylfluorene-2,7-diboronic acid bis(1,3-propanediol) ester and 3-substituted (R=3-methylbutyl,hexyl,2-(pyren-1-yl)vinyl) 2,5-dibromothiophenes and characterized by GPC,IR and NMR techniques.UV-vis absorption,photoluminescence (PL) and electrochemical behavior of these polymers were also studied.Though a similar absorption was observed in solutions and thin films of the polymers,the maximum at 400 nm for FIPT and F3HT and at 390 nm FPyT,PL of FPyT thin film differs from those of FIPT and F3HT thin films.They exhibited an intense green PL emission,whereas PL emission of FPyT thin film was orange with a red-shifted maximum compared with FIPT and F3HT indicating pronounced aggregation of FPyT in the solid state.Cyclic voltammetry showed that all the polymers are reversibly oxidized and reduced.A similar electrochemical behavior was observed for FIPT and F3HT whereas a higher electron affinity was estimated for FPyT.  相似文献   

11.
PVA偏光膜的制备新工艺及性能   总被引:2,自引:0,他引:2  
研究了一种新的偏光膜制备工艺,采用了乙烯醇为主体材料,内混有碘化钾,用过氧化氢氧化制备PVA偏光膜,实验结果表明:PVA基膜中含KI的量为1mmol/g,用w(H2O2)为10%的溶液氧化30s以上,经拉伸干燥后,可制备出有99%,以上偏光度的PVA偏光E  相似文献   

12.
用刮膜机在镜面不锈钢钢板上铺出聚乙烯醇(PVA)原膜,再经过染色、拉伸、补正等工艺制备PVA偏光膜.通过水热法制备的石墨烯量子点(GQDs)尺寸主要分布在2~4 nm,且其水溶液在500~400 nm间的光透过率下降22%,将PVA粉体溶在制得的GQDs水溶液中,制备PVA/GQDs复合偏光膜.结果表明:与PVA偏光膜相比,单片透过率略有下降,但GQDs的加入使偏光膜的直交透过率降低且低于0.1%,从而提高偏光膜的偏振度,达到99.9%以上.  相似文献   

13.
用改进的溶胶-凝胶技术,在硅和石英衬底上制备了不同浓度的Nd掺杂Ba0.80Sr0.20TiO3薄膜,应用XRD和SEM表征了薄膜的晶化行为和微观形貌.测试发现700℃退火后,薄膜晶化情况良好,具有典型的多晶钙钛矿结构,表面致密,无裂纹和孔洞,晶粒生长均匀,随着Nd掺杂量的增加,晶粒尺寸逐渐减小.在200~1 000 nm的波长范围内测试了薄膜的透射谱,用"包络法"计算了薄膜的折射率,薄膜折射率与波长呈现典型的电子带间跃迁的色散关系,波长为400 nm时,1%Nd(按物质的量计算百分比)掺杂的BST薄膜的折射率为2.06,小于纯BST薄膜的折射率2.10,这是由于Nd掺杂引起薄膜内部应力变化造成薄膜折射率降低.由吸收谱和Tauc关系确定了Nd掺杂对薄膜的光学带隙的影响.  相似文献   

14.
非晶态镍磷和镍钨磷双层复合镀膜的耐蚀性能研究   总被引:1,自引:0,他引:1  
主要对比研究了镍磷镀膜,镍钨磷镀膜以及镍磷和镍钨磷双层复合镀膜的耐蚀性能,分别进行了各镀膜的盐雾腐蚀试验和各镀膜的阳极化曲线的测定,然后根据实验结果,对比分析了以上三种镀膜的耐蚀性能。实验结果表明非晶态镍磷及镍钨磷双层复合镀膜的耐蚀性能优于其他两种镀膜的耐蚀性能。  相似文献   

15.
在锌表面获得多种具有金属光泽的不溶性Mo(W)-S彩色簇合物膜.膜层有良好的耐蚀性能和装饰效果,加热处理后其颜色发生变化,加速腐蚀试验结果表明,金黄色膜耐蚀性最佳.FT-IR、FT-Raman、XPS和AES分析表明,该膜层厚度约为60mm,钼在膜表面的价态为 6,而在膜内层则以 6、 4价共存.从AES深度分布曲线可知其组成为:Zn 32.5%,Mo 19.3%,S 39.4%,O 8.5%,膜为多分子层组成的复杂体系,其颜色是各组分统计分布的结果.  相似文献   

16.
聚苯胺膜电变色反应的椭圆偏振光谱   总被引:1,自引:0,他引:1  
用现场椭圆偏振技术在330-700nm波长范围内研究了从酸性水溶液中电聚合而成的聚苯胺膜的电变色反应。膜的还原态(-0.2V)在390-400nm、氧化态(0.55V)在500-530nm出现椭圆谱峰;从还原态(黄色)到氧化态(绿色)的电变色反应要经历一个中间态,其谱峰出现在466-470nm。  相似文献   

17.
采用溶胶-凝胶浸渍提拉法制备出纳米钇-铝共掺杂氧化锌(Y-AZO)透明薄膜,利用XRD、EDX、SEM、UV-Vis测试对薄膜进行了表征.结果表明:Y-AZO晶粒为六角纤锌矿结构,当Al的掺杂量高于或等于Y的掺杂量、退火温度为500℃时可以得到不含杂质的均匀透明的薄膜,且薄膜在400~780 nm 可见光范围内平均透过率在87%以上.  相似文献   

18.
用磁控溅射法在加热到400℃的MgO(001)基片上沉积了总厚度为25 nm 的[Fe(0.6 nm)/Fe30.5Pt69.5(1.9nm)]10 多层连续薄膜, 并对其在[500, 900]℃的温度范围进行了3h 的真空热处理. 结果表明, 薄膜在沉积过程中发生了层间扩散, 形成A1 相的FePt 合金, 表现为软磁特性; 热处理温度高于700℃时, 薄膜内形成L10 相的(001)织构, 其单轴磁晶各向异性能高于2.5×107 erg cc-1; 薄膜能在800℃以下保持形貌连续. 借助于半导体载流子扩散和复合模型, 对薄膜在高温下形貌保持连续的机理进行了探讨. 分析认为, 虽然薄膜在沉积过程中发生了层间扩散, 但内部仍然残存微弱的周期性成分起伏, 这可以有效阻碍热处理过程中因相变而引起的Pt 元素析出, 从而抑制了因形成富Pt 晶界而导致的形貌不连续. 这种薄膜可以方便地用于微加工制作磁性阵列和隧道结.  相似文献   

19.
以氯化钨(WCl6)、无水乙醇(C2H5OH)和二甲基甲酰胺(C3H7NO)为前驱体,以聚乙二醇(PEG-1000)为造孔剂,采用非水解溶胶-凝胶法制备WO3多孔薄膜,考察了PEG与WCl6添加比例对薄膜形貌结构和气敏特性的影响.结果表明,在PEG与WCl6添加比例为0.5时可获得形貌均一、孔隙率高、比表面积大的WO3多孔薄膜.所获WO3薄膜具有单一的单斜晶系结构,主要由直径为20~60nm的纳米颗粒所构成.气敏特性研究结果表明,WO3多孔薄膜呈现n型半导体特性,在最佳工作温度100℃时表现出对NO2良好的气敏性能;WO3薄膜的成膜机理表明,造孔剂PEG-1000引导无机材料形成高孔隙率和高比表面积的三维多孔薄膜结构,该多孔结构有望作为NO2气体的潜在气敏材料.  相似文献   

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