PAA/PVA复合纳米纤维膜的制备与吸湿性能研究

采用静电纺丝技术以2种亲水性聚合物聚丙烯酸(PAA)与聚乙烯醇(PVA)为原料制备复合纳米纤维膜,同时在纺丝溶液中添加无机盐氯化锂(LiCl)以提高纳米纤维膜的吸湿性能。利用扫描电镜、水接触角等方法对纳米纤维膜的微观形貌和亲疏水性能进行表征和测试;采用恒温恒湿系统对复合膜的吸湿性能进行测试。实验结果表明：当PAA、PVA混合质量比为5∶5时,纳米纤维的形态与吸湿性能最优;掺杂的LiCl质量分数为3.5%时,纤维膜吸湿性能最好,吸湿率可达到1.32 g/g。     

纳米尺寸聚丙烯酸锂颗粒的制备

在不同条件下,使用由分子量约为3 400的聚丙烯酸合成的聚丙烯酸锂制备了聚丙烯酸锂纳米颗粒,使用TEM观察了它们的形状和尺寸.实验条件下,以1体积的异丙醇为沉淀剂可得到最小宽度为72 nm的聚丙烯酸锂纳米晶;以1体积的异丙醇与2体积的石油醚为分散剂可以制备尺寸较均匀、分散良好的聚丙烯酸锂纳米球.考虑到原料成本,亦可使用1体积的无水乙醇作为制备亚微米(纳米)球状聚丙烯酸锂粒子的良好的分散剂.     

PS模板法制备铜纳米颗粒

采用双槽电化学腐蚀法制备多孔硅(porous silicon, PS), 对其进行超声后处理.以PS为模板采用一步浸渍沉积法制备大小均匀、形状规则的铜纳米颗粒, 并研究沉积时间对纳米颗粒形状、尺寸的影响.结果表明:PS超声后处理并未造成其物理和化学结构的破坏, 大量的硅氢键(SiH_x)和蜂窝状多孔结构(直径150 nm左右)分别为纳米铜的形成和生长提供了还原剂和场所;沉积时间对铜纳米颗粒形貌具有重要影响, 当沉积时间为40s时得到形状和尺寸较为均匀的铜纳米颗粒.     

羟乙基纤维素接枝聚丙烯酸纳米颗粒的制备及药物缓释

羟乙基纤维素接枝聚丙烯酸共聚物(HEC—g—PAA)在选择性溶剂中进行自组装，制备了具有良好分散稳定性的纳米颗粒，用动态激光光散射和透射电子显微镜对纳米颗粒大小分布和形态进行了表征。以生物可降解的HEC—g—PAA接枝共聚物负载模型药物布洛芬(Ibuprofen)，制备载药纳米颗粒(Ib—HEC—g—PAA)，在37℃于不同pH的缓冲溶液中进行了体外释放研究，药物释放速率的测定结果表明，以HEC—g—PAA作为布洛芬的载体，可以在选择性条件下实现药物可控释放的目的。     

明胶网络模板法合成La2O2S纳米颗粒

以明胶高分子网格为模板,硫酸氨为硫化剂,在较低温度下(700℃)通过氢气还原法制备La2O2S纳米颗粒。产物用差热-热重(DTA-TG)、X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和光致发光(PL)光谱分析方法进行表征。实验表明,明胶网格在稀土氢氧化物沉淀和热分解以及(LaO)2SO4生成过程中,能有效地控制颗粒的形貌,抑制颗粒的长大和团聚。用明胶网络模板法合成的La2O2S相纯度高,粒度均匀,粒子近似球形,大小约为30—50 nm。合成的(La0.95Tb0.05)2O2S和(La0.98Pr0.02)2O2S纳米粒子在水溶液中都观察到绿光发射,分别来源于Tb3 离子5D4到7Fj(j=3,4,5和6)的跃迁发射和Pr3 离子的3P0-3H4和3P1-3H4跃迁发射。     

气相沉积法制备单分散Cu纳米颗粒模板

针对纳米颗粒极易团聚而导致纳米材料失去特有功能的问题,鉴于常规物理、化学法无法彻底分散纳米颗粒的现状,创新性地运用了气相沉积法,提出了一种有效制备单分散Cu纳米颗粒模板的方法.该方法通过改变恒温时间、温度以及气体流速,制备了不同粒径、不同分散状态的单分散Cu纳米颗粒模板;运用扫描电子显微镜（SEM）、能量色散谱仪（EDS）对样品分别进行了微观形貌观察和化学成分分析.结果表明：恒温时间、温度、气体流速对颗粒尺寸、分散密度、覆盖率和粒度均匀性都有一定的影响.     

微乳液法制备ZnS纳米颗粒

采用了微乳液法制备ZnS纳米颗粒.该微乳液是以Span80-Tween60为复合表面活性剂,正丁醇为助表面活性剂,120#汽油为分散介质,乙酸锌水溶液为水相的反相微乳液体系.发现该微乳液的优化配比为22g汽油,4g复合表面活性剂（Span80-Tween60配比为1.11）,正丁醇1.5mL,乙酸锌水溶液（1.2mol/L）的最大增溶量为6.3mL,在此微乳液中,逐滴加入适量Na2S水溶液并搅拌,于室温下反应30min后,对反应体系进行破乳、洗涤、分离,最后将产物浸泡在无水乙醇中,并对该产物的乙醇溶胶进行超临界干燥,得到白色疏松的纳米粉.用X射线衍射仪（XRD）和透射电子显微镜（TEM）对产物的组成、大小、形貌进行了表征,结果表明产物主要为立方晶体结构的ZnS,粒子大小均匀,粒径为10～20nm,且分散性良好.     

锦纶织物超声波纳米颗粒复合化学镀镍磷

分别使用十二烷基苯磺酸钠、十六烷基三甲基溴化铵和海藻酸钠分散纳米Al2O3、Si3N4和ZrC颗粒,并将其添加到化学镀镍液中;在超声波辅助条件下对锦纶织物进行纳米颗粒复合化学镀镍磷;借助SEM、EDX、XRD和TG测试技术对镀层表面形貌、成分、结构和织物热性能进行研究,并测试织物阻燃、耐磨和电磁波屏蔽性能.结果表明:与普通化学镀镍磷织物相比,不同纳米颗粒复合化学镀镍磷织物镀层表面形貌有所不同;结晶度增大,当纳米颗粒添加量不大时,晶粒尺寸有所减小;热起始分解温度降低(纳米Si3N4除外),耐高温分解温度升高,燃烧速度有所减慢,没有熔滴现象发生;电磁波屏蔽效能变化不大,随着增重率的增加,平均屏蔽效能逐渐增大,表面电阻减小;耐磨性能增强.     

化学还原法制备银纳米颗粒

在70℃时采用聚乙烯吡咯烷酮(PVP)和氢氧化钠的混合水溶液,利用葡萄糖还原硝酸银制备了银纳米颗粒.采用X射线衍射(XRD)、能量分散谱(EDS)和扫描电子显微镜(SEM)对所制备的银纳米颗粒进行了表征.结果表明该法制备的银颗粒为纯的银纳米颗粒,呈球形,粒径分布集中在20～50 nm之间.     

磁性FeNi@C/Cu纳米颗粒制备及除油应用

为了处理港口码头薄油膜污染,在氩/氢气氛下利用电弧法制备Fe_0.64Ni_0.36为主相的合金纳米产物,采用水热法和高温碳化法制备碳包覆的核壳磁性FeNi@C/Cu复合纳米颗粒.对合金粒子以及碳包覆后的复合纳米颗粒进行表征及性能检测.结果表明：FeNi合金纳米粒子呈球状,500℃下制得的粒子饱和磁化强度最高,可以达到101.09 A·m²/kg,比常温下制备的粒子提升16.0%.利用FeNi@C/Cu复合纳米颗粒对煤油、柴油与机油的除油能力分别为3.18、3.43和3.46 g/g,表明FeNi@C/Cu复合纳米颗粒具有良好除油性能.     

复合型日志的模板提取方法

为了解决目前复合型日志无法被模板提取算法正确解析的问题,设计新的模板提取算法CLEA来处理复合型日志的模板提取. 该算法使用符号将所有日志划分为集群,基于Drain模板提取算法提取每个集群各自的日志模板,存储并缓存模板提取结果,在更新集群的同时更新缓存的模板;将差异度计算引入简单共有词算法中,增强简单共有词算法对模板中不同词语的敏感度,计算模板之间的相似度;设计BMerge算法,利用该算法对相似度大于阈值的模板进行合并,获取并输出合并日志作为最终结果. 在相似度算法中引入差异度计算,增强算法对模板中不同词语的敏感度,并设计BMerge算法对模板进行合并,输出无损日志作为结果. 所提方法适用于处理复合型日志,且正确率较高.     

Microstructure and abrasive wear behaviour of anodizing composite films containing Si C nanoparticles on Ti6Al4V alloy

Anodized composite films containing Si C nanoparticles were synthesized on Ti6Al4 V alloy by anodic oxidation procedure in C4O6H4Na2 electrolyte. Scanning electron microscopy（SEM）, energy dispersive spectroscopy（EDS） and X-ray photoelectron spectroscopy（XPS） were employed to characterize the morphology and composition of the films fabricated in the electrolytes with and without addition of Si C nanoparticles. Results show that Si C particles can be successfully incorporated into the oxide film during the anodizing process and preferentially concentrate within internal cavities and micro-cracks. The ball-on-disk sliding tests indicate that Si C-containing oxide films register much lower wear rate than the oxide films without Si C under dry sliding condition. Si C particles are likely to melt and then are oxidized by frictional heat during sliding tests. Potentiodynamic polarization behavior reveals that the anodized alloy with Si C nanoparticles results in a reduction in passive current density to about 1.54×10-8 A/cm2, which is more than two times lower than that of the Ti O2 film（3.73×10-8 A/cm2）. The synthesized composite film has good anti-wear and anti-corrosion properties and the growth mechanism of nanocomposite film is also discussed.     

Fabrication and photoluminescence property of CdS nanowire array by template electrodeposition

CdS nanowire arrays were synthesized by altering current（AC） electrodeposition in the porous anodic alumina film prepared by aluminium anodizing in oxalic acid. These nanowires have a uniform diameter of about 45 nm corresponding to the pore size of the films used and length up to several microns. The X-ray diffraction（XRD） pattern indicates that the CdS nanowires crystallize in an hcp structure. Besides, photoluminescences（PL） of CdS nanowire arrays, characterized by spectrophotometer show that CdS nanowries embedded in porous alumina template increases the light-emitting intensity and induces a red shift of PL band.     

Preparation of copper nano-wires by template synthesis method

Highly ordered and porous anodic aluminum oxide templates were prepared. The ordered copper nanowires arrays were assembled in nano-holes of the template by alternating current electrodeposition at lower voltage.The morphologies of template and copper nano-wires arrays were characterized by means of field emission scanning electron microscope(FESEM) and the crystal structure of copper nano-wires was determined by means of X-ray diffraction. The results indicate that copper nano-wires hold the preferred crystalline orientation along (111), (200),(220) and (331) crystal faces during growth, and the growth of copper nano-wires in the nano-holes of the template is homogenous and continuous.     

Structures and properties of PEDOT nanotubes prepared by a template synthesis method

PEDOT nanotubes were prepared by a template synthesis method. Based on our template, it was deduced that there are two successive processes in the formation of nanotubes. The first step is soakage of the porous templates by a polymer solution, and the second step is adsorption of free charged cationic groups and doped PEDOT onto the template surface with negative charges. XRD results showed that well orientated PEDOT chains were formed during the synthesis, moreover the arrange conductivity of molecular chains strongly affect the structures of PEDOT nanotubes. The nanotubes were measured to be about 5.5–17.6 S/cm, which is higher than that of nanotube pellet due to the high contact resistance between the adjacent nanotubes. Funded National Natural Science Foundation of China(No.: 60372002)     

Sol-Gel法制备NiTiSMA/FC多层薄膜复合材料的组成结构研究

研究用Sol—Gel法在NiTiSMA薄片基体上复合铁电陶瓷薄膜的工艺，讨论了热处理温度对铁电陶瓷层晶化的影响。结果表明，NiTi基体的高温氧化行为直接影响着铁电陶瓷层的结晶过程，并又随着陶瓷层结构的致密化该作用减弱。     

纳米Cr颗粒对Ni-Mo复合镀层性能的影响

为了研究纳米Cr颗粒对Ni-Mo复合镀层性能的影响,采用脉冲电沉积方法制备具有不同Cr含量的Ni-Mo复合镀层.利用扫描电子显微镜和X射线衍射仪分别观察和分析复合镀层的组织形貌及结构.采用电化学测试和X射线光电子能谱研究复合镀层的析氢性能和耐蚀性能.结果表明:随着镀液中纳米Cr颗粒含量的增加,镀层晶粒得到细化,析氢过电位增大,复合镀层析氢性能得到提高;当镀液中纳米Cr颗粒含量为20 g/L时,复合镀层表面钝化膜中MoO₃含量较高,且可与Cr产生协同效应,因而复合镀层具有较好的耐蚀性能;但随着镀液中纳米Cr颗粒含量的进一步增加,复合镀层中沉积的Cr元素含量降低,复合镀层的析氢性能和耐蚀性能均降低.因此,当镀液中纳米Cr颗粒含量为20 g/L时,复合镀层具有较好的析氢性能和耐蚀性能.     

Characteristics of magnetic Fe3O4 nanoparticles encapsulated with human serum albumin

Magnetic nanoparticles （Fe304） were prepared by chemical precipitation method using Fe^2＋ and Fe^3＋ salts with sodium hydroxide in the nitrogen atmosphere. Fe3O4 nanoparticles were coated with human serum albumin（HSA） for magnetic resonance imaging as contrast agent. Characteristics of magnetic particles coated or uncoated were carried out using scanning electron microscopy and X-ray diffraction. Zeta potentials, package effects and distributions of colloid particles were measured to confirm the attachment of HSA on magnetic particles. Effects of Fe3O4 nanoparticles coated with HSA on magnetic resonance imaging were investigated with rats. The experimental results show that the adsorption of HSA on magnetic particles is very favorable to dispersing of magnetic Fe3O4 particles, while the sizes of Fe3O4 particles coated are related to the molar ratio of Fe3O4 to HSA. The diameters of the majority of particles coated are less than 100 nm. Fe3O4 nanoparticle coated with HSA has a good biocompatibility and low toxicity. This new contrast agent has some effects on the nuclear magnetic resonance imaging of liver and the lowest dosage is 20μmol/kg for the demands of diagnosis.     

包覆法制备Gp/SiC复合材料的显微结构和性能

以不同粒径的石墨颗粒和SiC粉体为原料,采用SiC粉体包覆石墨颗粒的方法,于2000℃热压制备了石墨/碳化硅（Gp/SiC）复合材料.利用扫描电子显微镜（SEM,EDS）分析了材料的金相和断口显微结构.研究表明,石墨粒径较小且质量分数较少的复合材料比石墨粒径较大且质量分数较多的复合材料在热压工艺中更致密.石墨颗粒呈岛状紧密地镶嵌在SiC基体中,石墨与SiC界面处C和Si的扩散不明显.复合材料的相对密度、抗折强度,断裂韧性和硬度随石墨粒径和质量分数的减少而增加.断口形貌表明SiC陶瓷基体为脆性,石墨为韧性断裂.当石墨粒径为125μm、SiC与石墨的质量比为3.5时,复合材料的综合性能最佳,开口气孔率为0.3%,相对密度为97.9%,抗折强度为75±15 MPa,断裂韧性为5.4±0.5 MPa.m1/2,硬度为26.8±3GPa.     

Electrochemical performance of LiFePO4/（C＋Fe2P） composite cathode material synthesized by sol-gel method

A LiFePO4/(C+Fe2P) composite cathode material was prepared by a sol-gel method using Fe(NO3)3·9H2O,LiAc·H2O,NH4H2PO4 and citric acid as raw materials,and the physical properties and electrochemical performance of the composite cathode material were investigated by X-ray diffractometry(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM) and electrochemical tests.The Fe2P content,morphology and electrochemical performance of LiFePO4/(C+Fe2P) composite depend on the calcination tempera...