A novel Fe/HNT visible light-driven heterogeneous photocatalyst: Development as a semiconductor and photocatalytic application

Fe/HNT (Iron/Halloysite-nanotube) heterogeneous semiconductor catalysts operating effectively under visible light were developed by using FeCl₃, FeSO₄ and Fe(OH)₃ sludge precipitated after electro-Fenton process and named as Fe/HNT-I, Fe/HNT-II and Fe/HNT-III, respectively. Chemical configuration and particle morphology of the catalysts were characterized with XRD, SEM-EDS and UV–vis DRS. Effect of the developed Fe/HNT photocatalysts was investigated for the degradation of Reactive Orange 16 (RO16) textile dye under visible light. The photocatalytic decolorization of RO16 was 95.6%, 99.3% and 96.6%, respectively. It was found that the photocatalytic performance of Fe/HNT-III catalyst under visible light was effective compared to Fe/HNT-I and Fe/HNT-II. The iron ratio in the catalyst's structure (Fe:HNT ratio 0.25, 0.5 and 0.75 (w/w)) and pH value (4, 7 and 9) in production phase were also changed to investigate the photocatalytic effect of Fe/HNT-III. An Fe:HNT ratio of 0.25 and a pH of 4 were determined as the optimum conditions for catalyst production. Optimum H₂O₂ dosage value was also investigated for photocatalytic oxidation process and determined to be 10 ?mM. Finally, the optimum conditions were further used for the degradation of Terbinafine hydrochloride (TerHCl) active drug and the treatment of wastewater from the textile and pharmaceutical industries.     

A relevant in vitro rat model for the evaluation of blood-brain barrier translocation of nanoparticles

Poly(MePEG₂₀₀₀cyanoacrylate-co-hexadecylcyanoacrylate) (PEG-PHDCA) nanoparticles have demonstrated their capacity to reach the rat central nervous system after intravenous injection. For insight into the transport of colloidal systems across the blood-brain barrier (BBB), we developed a relevant in vitro rat BBB model consisting of a coculture of rat brain endothelial cells (RBECs) and rat astrocytes. The RBECs used in our model displayed and retained structural characteristics of brain endothelial cells, such as expression of P-glycoprotein, occludin and ZO-1, and immunofluorescence studies showed the specific localization of occludin and ZO1. The high values of transendothelial electrical resistance and low permeability coefficients of marker molecules demonstrated the functionality of this model. The comparative passage of polyhexadecylcyanoacrylate and PEG-PHDCA nanoparticles through this model was investigated, showing a higher passage of PEGylated nanoparticles, presumably by endocytosis. This result was confirmed by confocal microscopy. Thanks to a good in vitro/in vivo correlation, this rat BBB model will help in understanding the mechanisms of nanoparticle translocation and in designing new types of colloidal carriers as brain delivery systems.Received 4 March 2005; accepted 14 April 2005     

金纳米粒子二维有序阵列的构筑和电化学性质

在水溶液中用柠檬酸钾还原氯金酸的方法合成了粒径为30～40nm的金纳米粒子,并用透射电镜和紫外可见光谱进行了表征;然后在表面经PVP修饰的导电玻璃上以自组装的方式构筑了金纳米粒子的二维有序阵列,并用扫描电镜和紫外可见光谱进行了表征;以所制备的金纳米粒子二维有序阵列作为电极,对硝基苯酚的电化学响应得到明显提高,金纳米有序阵列电极有望成为检测废水中对硝基苯酚的电化学传感器.     

Preparation and cytocompatibility of polylactic acid/hydroxyapatite/graphene oxide nanocomposite fibrous membrane

A series of polylactic acid (PLA) based nanocomposite fibrous membranes,including neat PLA,PLA/hydroxyapatite (HA) and PLA/HA/graphene oxide (GO),were fabricated via electrospinning method.The morphology and composition were investigated by scanning electron microscopy (SEM),X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) respectively.The thermal stability was determined by thermogravimetric analysis (TGA).To estimate the cytocompatibility of asprepared PLA/HA/GO fibrous membrane,MC3T3-E1 cells were cultured,and the corresponding cell adhesion and differentiation capability were investigated by fluorescence microscopy,SEM and MTT test.The electrospun ternary PLA/HA/GO membrane exhibited three-dimensional fibrous structure with relatively rough surface morphology,which made itself ideal for cell attachment and proliferation in bone tissue regeneration.The fluorescence microscopy,SEM and MTT test confirmed that the PLA/HA/GO nanocomposite fibrous membrane created a proper environment for the seeding and proliferation of MC3T3-E1 cells.     

基于海洋生物多聚物的功能因子递送系统

基于海洋多聚物的纳米材料是一种新型的功能因子负载体系,临床应用中药物与功能因子的递送方式主要有3种,分别是口服、经皮和注射,但由于体感差、药物递送量低、副作用和有效成分活性丧失等诸多问题的困扰,人们更加希望选择既能提高医疗效果和健康水准,又能满足良好舒适性的传输递送方式。研究发现基于海洋多聚物的纳米材料与传统口服递送体系的系统结合可以实现抗癌药物、营养物质、益生菌、疫苗等功能成分的高效递送,大大提高了上述成分的整体生物利用度。通过阐述纳米载体的制备、功能因子的负载及其吸收机制为基于海洋多聚物功能因子递送体系的发展提供参考和借鉴。     

PEO修饰中空SiO2纳米颗粒的制备及生长机理研究

采用基于PluronicF127胶束的软模板法,在中性、室温和无催化剂的温和环境下,制备得到中空SiO2纳米颗粒.利用透射电子显微镜(TEM)、动态光散射粒度分布测定仪(DLS)和傅里叶转换红外光谱仪(FT-IR)对所制备的中空SiO2纳米颗粒的形貌、粒径和官能团进行分析.结果表明:SiO2壳层成功在F127胶束疏水-亲水界面处形成,PEO在中空SiO2纳米颗粒表面可自由伸展,纳米颗粒的尺寸随F127浓度增加而减小,但分散性随F127浓度增加而增强.F127质量为15mg、四甲氧基硅烷为46μL时制备的中空SiO2纳米颗粒的平均粒径和内径分别为20nm和9.6nm,且具有更好的水溶性和单分散性.通过对样品的TEM照片统计分析发现,中空SiO2纳米颗粒的外径、内径和SiO2壳层厚度与F127浓度密切相关.     

Effects of Au nanoparticle addition to hole transfer layer in organic solar cells based on copper naphthalocyanine and fullerene

Organic solar cells based on copper naphthalocyanine(CuNc) and fullerene(C60) were fabricated, and their photovoltaic properties were investigated. C60 and CuNc were used as n-type and p-type semiconductors, respectively. In addition, the effect of Au nanoparticle addition on a hole transfer layer was investigated, and the power conversion efficiency of the devices was improved after blending the Au nanoparticles into the hole transport layer. Nanostructures of Au nanoparticles were investigated by transmission electron microscopy and X-ray diffraction. Energy levels of molecules were calculated by molecular orbital calculations, and the nanostructure and electronic properties were discussed.& 2014 Chinese Materials Research Society. Production and hosting by Elsevier B.V. All rights reserved.     

不同反应温度和原料对化学沉淀法制备纳米羟基磷灰石的影响

使用不同磷源与钙源制得纳米羟基磷灰石,并利用X射线衍射、红外光谱、透射电镜、热重分析等分析手段对产物进行表征,探究不同的反应温度、不同原料等实验条件对产物的组成、形貌及尺寸的影响。结果表明：升高温度有利于晶体生长;不同钙源对产物的影响不大,改变磷源对产物组成的影响较大;产物羟基磷灰石中的磷酸根会被磷酸氢根所取代,并且以磷酸氢二钠为原料时产物中磷酸氢根含量最高。     

Au@SiO2颗粒对石墨烯量子点拉曼信号的增强作用

采用金纳米颗粒包覆了一层二氧化硅壳层作为实验材料,利用该核壳材料增强石墨烯量子点的拉曼信号,并实现了单颗粒增强.实验中,二氧化硅的厚度可以通过反应时间得到控制,该壳层可以增强金纳米颗粒的化学和物理稳定性.本文方法与使用纯金纳米颗粒增强石墨烯量子点拉曼信号相比,其拉曼信号强度增强了20%以上.     

PdO_x/金属磷酸盐催化剂催化分解N_2O

使用商业化的金属磷酸盐(M-P-O,M=Mg,Al,Ca,Fe,Co,Zn,La)为载体,以Pd(NO_3)_2为PdOx的前躯体,制备了PdOx/M-P-O系列催化剂,并测试了催化剂的N_2O分解性能.发现PdOx/Ca-P-O(又记为PdOx/HAP,HAP为羟基磷灰石)在该系列样品中表现出最佳催化活性,在反应温度375℃时能催化N_2O完全转化.而其他PdOx/M-P-O催化剂几乎没有活性.O2在反应气中的共存对PdOx/HAP的活性影响很小,而H_2O蒸气的共存明显抑制活性.但O2和H_2O蒸气对活性的影响是可逆的,即O2或者H_2O撤走后,活性复原.PdOx/HAP在无O2和有O2情况下都保持较好的稳定性.使用4%H2,在400℃对PdOx/HAP进行预处理能提高催化活性.使用XRD、TEM、XPS、ICP等对PdOx/HAP进行了表征.