铜掺杂纳米 TiO2 的制备及其抗菌性能研究

目的制备铜掺杂纳米二氧化钛抗菌材料,测定其金属溶出率,研究该材料的光催化活性及抗菌性能。方法通过水热合成法制备掺铜二氧化钛(TiO_2Cu)纳米材料,采用催化动力学法测定该材料Cu~(~(2+))溶出率,以亚甲蓝为光催化降解材料测定其光催化活性,以金黄色葡萄球菌为目标物,研究在紫外光和非光条件下TiO_2Cu纳米材料的抗菌性能。结果 TiO_2Cu纳米材料Cu~(2+)溶出率最大值为72.36%,在自然光和紫外灯光照下对亚甲蓝光催化降解率分别为95.06%和85.08%,光照下TiO_2Cu材料质量浓度达到10 mg/m L,与细菌共培养90 min后,抑菌率可达94%。结论采用冷冻干燥法制备的含铜量为0.2%的TiO_2Cu材料具有良好的光催化活性,在暗光和紫外光照下均具有一定的抗菌性能。     

模拟体液法快速合成羟基磷灰石纳米针及其吸附性能研究

采用模拟体液法快速制备羟基磷灰石(HA)纳米针,并研究了HA对牛血清蛋白质(BSA)的吸附性能。采用XRD、TEM、SEAD和FT-IR等分析方法表征样品。结果表明:1min即可快速制备宽约5nm,长为50～80nm且分散良好的HA纳米针,形貌和尺寸与人体中的HA极为相似;反应时间影响合成产物的形貌及物相,短时间内延长反应时间有利于HA纳米针的生长,但反应时间过长会导致HA再次反应生成Ca3(PO4)2;同时,快速制备的HA纳米针具有很强的吸附性能。     

奥氏体抗菌不锈钢的微观组织及抗菌性能

含Cu奥氏体抗菌不锈钢经特殊的抗菌热处理析出ε—Cu相,采用覆膜法研究其抗菌性能。实验结果表明：奥氏体抗菌不锈钢易于杀灭大肠杆菌和金黄色葡萄球菌;杀灭鼠伤寒杆菌需要一定时间;杀灭白色念株菌需要较长时间。这与细菌的细胞壁组织结构、细胞壁厚度及其属性有关。抗菌不锈钢对细胞壁较薄、肽聚糖含量较低、组织疏松、金属离子易穿透细胞壁的细菌易于杀灭;反之,细菌不易于杀灭。随着抗菌作用时间的延长,溶液中铜离子浓度的提高,抗菌不锈钢的杀菌效力显著提高。奥氏体抗菌不锈钢经表面打磨或磨损仍然具有同样的抗菌性能。     

Cu2+-TiO2/蒙脱石自净化功能材料的制备及性能研究

以蒙脱石为载体,通过溶液离子交换以及高温灼烧的方法,将具有抗菌活性的Cu2+固载到载体的孔道中,同时将具有光催化降解自净化功能的TiO2插入到硅酸盐的层间。得到了对大肠杆菌(8099)和金黄色葡萄球菌(ATCC6538)抗菌率为99.99%、光催化降解亚甲基蓝溶液的净化率为92.65%的自净化功能基元材料Cu2+ TiO2/蒙脱石(Cu2+ TiO2 M)。     

Ca3CO2O6与掺铜体系的量子化学计算

采用离散变分密度泛函方法计算了Ca3Co2O6及掺铜体系,讨论了电子结构、化学键等与热电性能之间的关系.结果表明,一维Co-O链对材料的电学性能起着主导作用,Ca-O之间的弱结合导致材料具有较低的热导率.价带和导带主要由Co3d、Cu3d和O2p原子轨道贡献,价带和导带之间的能隙宽度表现半导体电子结构特征,且掺铜体系的能隙变窄,离子键和共价键减弱.由此推断,掺铜后体系的热电性能将有所改善.     

复合沸石抗菌材料及其抗菌性能的研究

本文利用离子交换法将沸石与具有抗菌性能的锌铜离子合成双组分抗菌沸石,研究了反应时间、温度、交换的金属溶液的浓度和沸石与金属离子溶液的固液比对抗菌剂载金属含量及抗菌性能的影响,同时也比较了单金属组分沸石与双金属沸石抗菌性能的差异。实验表明,制备锌铜双组分抗菌沸石的最佳工艺条件为：反应时间2h,温度90℃,沸石质量与金属离子溶液体积比1：10,锌铜含量相差最少则锌铜离子浓度比为1：1。     

聚丙烯酰胺改性羟基磷灰石的制备及吸附Cu~(2+)研究

用聚丙烯酰胺(PAM)对用微乳液法合成的纳米羟基磷灰石(HA)粉体进行有机改性制备。通过用X射线衍射(XRD)、扫描电镜(SEM)、傅立叶转换红外光谱(FT-IR)等测试手段对合成的粉体的化学组分、粒度大小、表面形态进行表征分析。实验结果表明,PAM使HA晶体发生相转变,有CaHPO4的生成。PAM改性后HA杆状颗粒由80 nm变为120nm。1 635.6cm-1特征峰表明PAM与HA中的Ca2+发生络合,使PAM接枝在HA表面。另外,探讨了不同质量分数的PAM-HA改性粉体水中分散性及吸附重金属离子(Cu2+)性能研究。     

铜型无机抗菌材料的改性研究

研究了添加电解质、表面活性剂和有机溶剂对铜型抗菌白炭黑性能的影响.采用溶胶-凝胶法制备出白炭黑载体,选用Cu2+作为抗菌离子,亚硝酸钠(电解质)、十二烷基苯磺酸钠(表面活性剂)和乙醇(有机溶剂)作为添加剂.运用ICP、粒度分布仪等对改性后的抗菌白炭黑进行表征,采用菌落计数法(菌种选用大肠杆菌)对改性后样品的抗菌性能进行研究.结果表明:通过改性,铜型抗菌白炭黑的抗菌离子含量和杀菌率均有所提高；粒径均一,粒度分布窄；热稳定性较好.     

载铜锌纳米羟基磷灰石的抗菌性能及机理研究

在常压下合成了纳米羟基磷灰石（n—HA）浆料，并在水介质中制备了载铜、载锌和载铜锌双离子n—HA抗菌材料．运用原子吸收光谱（AAS）、转靶X射线衍射（XRD）、透射电镜（TEM）等手段对材料的理化性能进行了表征．并对该抗菌材料的抗菌性能进行了研究．结果表明，载铜和载铜锌双离子n—HA抗菌材料对革兰氏阴性菌E．coil和革兰氏阳性菌S．aureus均有较强的抑制和杀灭作用，而载锌n—HA的抗菌能力较弱．本文还通过实验探讨了该抗菌材料的抗菌机理．     

铜离子注入马氏体不锈钢的抗菌性能研究

Cu离子由MEVVA离子注入机引出注入2Cr13不锈钢,采用60keV的能量、(0.2～2.0)×1017ions/cm2剂量。计算了60keV能量下Cu离子的饱和注入量。研究了2Cr13不锈钢在铜离子注入后所具有的抗菌性能,分析了注入量对样品抗菌性能的影响。抗菌实验结果表明,注入量接近饱和注入量时,样品具有最佳的抗菌性能。     

Zn掺杂CuO/CuAl2O4复合空心球的制备及光催化性能

以葡萄糖为模板, 硝酸锌、硝酸铜和硝酸铝为原料, 采用水热法制备高比表面Zn-CuO/CuAl₂O₄复合空心球。采用XRD、SEM、HRTEM、BET、DRS和PL等手段对样品进行表征, 结果表明: 在600℃下焙烧的Zn-CuO/CuAl₂O₄复合物呈空心球状, 球体直径约为2 μm, 比表面积高达214.97 m²/g。引入Zn有助于提高样品对紫外和可见光的吸收能力, 减少光生电子空穴对的复合, 光催化活性显著提高。在模拟太阳光照下, 以甲基橙溶液为目标降解物, 考察样品的煅烧温度和Zn加入量对光催化活性的影响。当Zn加入量为0.5wt%, 煅烧温度为600℃时, 样品的光催化活性最佳。光照60 min, 0.5 g/L光催化剂用量对25 mg/L甲基橙溶液的脱色率高达97%。     

Solution-phase synthesis of smaller cuprous oxide nanocubes

Smaller cuprous oxides (Cu₂O) nanocubes were synthesized by solution-phase method at 160 °C, using ethylene glycol reducing Cu(NO₃)₂·3H₂O with poly(vinylypyrrolidone) (pvp) as capping agent. The Cu₂O nanocubes were characterized by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and X-ray powder diffraction (XRD). SEM showed that most of Cu₂O nanocubes were uniform and monodisperse, with the average edge length about 130 nm. The TEM results were consistent with the SEM results. Selected area electron diffraction (SAED) suggested that as-prepared Cu₂O nanocubes were single crystalline. The geometric shape and size of Cu₂O nanoparticles were greatly affected by the presence of PVP and its molar ratio (in repeating unit) relative to copper nitrate, temperature and the concentration of Cu(NO₃)₂·3H₂O. The mechanism of Cu₂O nanocubes formation was also discussed.     

微波辅助溶剂热法制备磷酸钙微球和多面体

磷酸钙材料具有良好的生物相容性, 被广泛应用于生物材料领域。本研究以Ca(CH₃COO)2、NaH₂PO₄?2H₂O和双亲嵌段共聚物PLA-mPEG为原料, 通过微波辅助120℃水热反应30 min, 合成了自组装结构磷酸钙微球。以相同的反应原料, 在水和乙二醇混合溶剂中, 通过微波辅助120℃溶剂热反应30 min, 制备了具有多面体结构的磷酸钙。通过X射线粉末衍射(XRD)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)和热重分析(TG)对所制备样品的物相和形貌进行了表征。研究发现乙二醇的加入对磷酸钙的结构和形貌具有显著的影响。以牛血红蛋白为模型, 研究了所制备的两种不同磷酸钙材料的蛋白吸附效果。磷酸钙材料的牛血红蛋白吸附量随装载溶液中牛血红蛋白浓度的增加而增大, 随样品制备过程中的乙二醇加入量的增加而减小。     

柠檬酸钠调控水热合成羟基磷灰石微球

本研究采用四水硝酸钙(Ca(NO₃)₂·4H₂O)和磷酸氢二铵((NH₄)₂HPO₄)分别作为钙源和磷源, 以丙酰胺为pH调节剂调控溶液的过饱和度, 以柠檬酸钠为钙源缓释剂调控羟基磷灰石(Hydroxyapatite, HA)的形貌, 经水热法处理成功制备出高结晶度、形貌均一和分散性良好的HA微球。采用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)和扫描电镜(SEM)对反应产物进行了表征, 研究了初始pH值、柠檬酸钠加入量和水热反应温度对HA结晶度、组成及形貌的影响。研究结果表明, 当初始pH值为3, 柠檬酸钠与钙源的摩尔比为1︰1.5, 反应温度为180℃时, 有利于HA微球的形成。     

酚醛树脂原位催化裂解制备低维碳纳米结构

以Ni（NO₃）₂·6H₂O为催化剂前躯体,原位催化裂解酚醛树脂制备了碳洋葱、竹节碳和碳纳米管等低维碳纳米结构;用粉体X-射线衍射（XRD）、扫描电镜（SEM）和透射电镜（TEM）等手段对低维碳纳米结构进行了表征。结果表明;当Ni（NO₃）₂·6H₂O与苯酚物质量比小于0.01时,Ni催化剂易分散,碳纳米管易生成,管径均一、分布稠密;当Ni（NO₃）₂·6H₂O与苯酚物质量比大于0.04时,Ni催化剂易团聚,碳纳米管管径分布较宽,分布稀疏;当Ni（NO₃）₂·6H₂O与苯酚物质量比为0.10时,Ni催化剂团聚现象严重,难以生成碳纳米管;提出了碳洋葱、竹节碳和碳纳米管不同碳纳米结构可能的形成机理。     

Preparation of irregular mesoporous hydroxyapatite

An irregular mesoporous hydroxyapatite (meso-HA), Ca₁₀(PO₄)₆(OH)₂, is successfully prepared from Ca(NO₃)₂·4H₂O and NH₄H₂PO₄ using surfactant cetyltrimethyl ammonium bromide (CTAB) as template. Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) results reveal that the positive head of CTAB is assembled on the surface precipitated HA and much NH₄⁺ is enclosed in precipitated HA before calcination. Field scanning electron microscope (FSEM) reveals that there exist many interconnected pores throughout the HA reticular skeleton. Nitrogen adsorption–desorption experiment exhibits a mesoporous material type IV curve, and pore size distribution calculated from the desorption branch of the isotherms based on Barrett–Joyner–Halenda (BJH) model shows that most pores throughout the HA reticular skeleton are sized at about 40 nm, but the pores are not uniform on the whole, owning to decomposition of the “organic” CTAB templating structures and ammonium salt enclosed in the precipitated HA. The specific surface area of irregular meso-HA is calculated to be 37.6 m²/g according to the Brunauer–Emmett–Teller (BET) equation. Moreover, after polylactic acid/meso-HA (PLA/meso-HA) composites degraded 12 weeks in normal saline at 37 °C, the interconnected pores throughout the HA skeleton were enlarged and sized in micron degree, which resemble trabecular bone structure very much.     

表面活性剂对羟基磷灰石纤维形貌的影响

以Ca(NO₃)₂·4H₂O和(NH₄)₂HPO₄水溶液为前驱体, 采用水热均相沉淀法制备了结晶度较高的羟基磷灰石纤维, 研究了表面活性剂十六烷基三甲基溴化胺(CTAB)、十二烷基硫酸钠(SDS)和聚乙二醇(PEG)及其含量对产物形貌和相组成的影响。结果表明, 采用这三种表面活性剂制备的产物都是羟基磷灰石, 部分样品含有少量碳酸钙杂质。加入CTAB和SDS均会对纤维的生长起到抑制作用, 得到纤维与球形团聚体并存的产物, 而PEG的加入在一定程度上促进了纤维的生长。     

Effect of preparation conditions on properties of atomic layer deposited TiO2 films in Mo–TiO2–Al stacks

TiO₂ films were grown by atomic layer deposition on Mo electrodes in order to elucidate the dominating conductance mechanism and its dependence on the growth chemistry. TiCl₄ and Ti(OC₂H₅)₄ served as titanium precursors, and H₂O or H₂O₂ as oxygen precursors. The films grown at lower temperatures were amorphous. With increasing growth temperatures the crystallization first started in the TiCl₄–H₂O process. The films grown in this process were clearly leakier compared to the films grown from Ti(OC₂H₅)₄ and H₂O and from Ti(OC₂H₅)₄ and H₂O₂. In the Ti(OC₂H₅)₄-based processes, the application of H₂O₂ instead of H₂O resulted in the films with considerably lowered conductivity, although structural differences in these films were insignificant. Space–charge-limited currents were prevailing in all our amorphous Mo–TiO₂–Al packages. Measurements at different temperatures suggested quite high trap densities likely due to the presence of impurities and structural disorder, while the strong differences in conductivity seemed to be due to different densities of gap states.     

一步法制备三维还原氧化石墨烯/NiO超级电容器电极材料及其性能研究

本研究以氧化石墨烯分散液(GO)和硝酸镍(Ni(NO₃)₂·6H₂O)为前驱体, 通过一步水热法制备自支撑三维还原氧化石墨烯/NiO复合电极材料(3D rGO/NiO)。用XRD和SEM等分析结果表明, 纳米NiO颗粒均匀分散在三维多孔石墨烯表面。当GO与Ni(NO₃)₂·6H₂O质量比为1 : 4时, 3D rGO/NiO在电流密度为1 A·g^-1 下比电容可达1208.8 F·g^-1; 当电流密度从0.2 A·g^-1增加到10 A·g^-1时, 复合电极材料电容保持率高于72.6%; 在电流密度为10 A·g^-1下进行恒流充放电循环测试10000次后, 其比电容仍然保持为初始比电容的93%, 表明该复合电极材料具有良好的倍率性能和循环稳定性能。3D rGO/NiO复合电极材料具有比纯NiO或rGO更优异的电化学性能。     

Synthesis temperature dependence of morphologies and properties of cobalt oxide and silicon nanocrystals

Cobalt and cobalt oxide nanocrystals were synthesized on Si substrates from aqueous cobalt nitrate [Co(NO₃)₂·6H₂O] powder via chemical vapor deposition method. Scanning electron microscope, field emission scanning electron microscope, and transmission electron microscope observations show different morphologies, such as continuous films, nano-bars, nano-dices, and nano-strings, depending on the synthesis temperature. The crystal structure characterization was conducted using X-ray diffraction methods. Furthermore, the properties of the samples were characterized using Raman spectroscopic analysis and vibrating sample magnetometer. The morpholo- gy change was discussed in terms of synthesis environments and chemical interactions between cobalt, oxygen, and silicon.