铈硅包覆金红石型钛白粉及光催化性研究

采用溶胶-凝胶法,制备了铈硅包覆金红石型钛白粉,通过正交实验考察了浆液浓度、分散剂用量和两种包膜剂含量对铈硅包覆金红石型钛白粉性能的影响。采用Nano-ZS型粒度仪、扫描电镜（SEM）、透射电镜（TEM）和能谱（EDS）等测试手段,对金红石型钛白粉的Zeta电位、表面形貌和元素进行了表征。结果表明：在水浴温度为80 ℃左右、转速为600 r/min、浆液质量浓度为400 g/L、分散剂质量分数为0.1%、二氧化铈质量分数为3%、二氧化硅质量分数为4%的条件下,金红石型钛白粉表面包覆了两层均匀而致密的二氧化硅和二氧化铈膜;罗丹明B光催化降解实验证实,铈硅包覆明显改善了金红石型钛白粉的光催化屏蔽性。     

Preparation of CuO nanopowders and their catalytic activity in photodegradation of Rhodamine-B

CuO nanopowders have been successfully synthesized in two different morphologies from same precursor using a facile gel to crystalline (reflux) and co-precipitation synthesis routes. SEM and TEM observations indicate that the morphology of the products depends on preparation technology, while XRD shows the formation of CuO nanocrystals with monoclinic crystal system in both cases. A comparison of morphological characterization of CuO nanopowders showed flower-like and aggregated nanoparticles in the form of clusters using reflux and co-precipitation techniques, respectively. Photocatalytic activity of the products in the aqueous solution of Rhodamine-B has been investigated under UV-light for a given time using UV–visible spectroscopy and the mineralization of organic substance was measured by total organic carbon (TOC) analysis. It was observed that the photocatalytic activity in the presence of flower-like CuO nanopowders was higher than that of observed with aggregated nanoparticles. Also the mechanisms for the formation of CuO nanopowders and the obtained results of photocatalytic degradation of Rhodamine-B are discussed.     

Competitive removal of malachite green and Rhodamine-B using Amberlite-XAD-4 impregnated with Aliquat 336: experimental and modelling studies

ABSTRACT

Use of solvent impregnated resin in the separation has emerged as a new area of interest. It is a hybrid process with the characteristics of adsorption, ion-exchange and extraction. Here, Aliquat 336 impregnated Amberlite XAD-4 resin was used to remove Rhodamine-B and malachite green individually and from their mixtures in the aqueous solution. The performance of prepared resin was studied in batch mode to analyze the effect of adsorbent dosage, pH, concentration of dye solution, salt concentration, time, and temperature. Characterization (using FE-SEM, EDS, FTIR, and point of zero charge), regeneration, and cost analysis of the adsorbent were also done.     

高分子基体的固体染料激光器的制备和研究

制备了用于固体染料激光器的高分子共聚物基体 ,研究了两种激光染料 Rhodamine- B(Rh-B)和 Pyrromethene597(PM- 597)在高分子基质中的光谱性质。以调 Q的 Nd:YAG激光器的倍频光为抽运光源 ,在无外加谐振腔的条件下 Rh- B和 PM- 597掺杂的高分子基体中获得了高转换效率和大能量激光输出 ,可为固体染料激光器的实用化提供关键工作物质     

香蕉皮的干燥及对罗丹明B的吸附

以香蕉皮为原料,考察3种干燥法(自然干燥、烘箱干燥和微波干燥)对制备香蕉皮粉的影响,并测定其对罗丹明B的吸附性能. 结果表明,采用微波干燥法,在功率800 W的条件下仅需4 min即成功制备出高脱水率(90%)、易研磨且外观和结构保持较好的香蕉皮粉;香蕉皮粉对罗丹明B具有良好的吸附性能,其吸附量(>110 mg/g)高于多数其他生物吸附剂的吸附量;香蕉皮粉结构中羧基和羟基等官能团促进了罗丹明B的吸附.     

Preparation of hollow magnetite microspheres and their applications as drugs carriers

ABSTRACT: Hollow magnetite microspheres have been synthesized by a simple process through a template-free hydrothermal approach. Hollow microspheres were surface modified by coating with a silica nanolayer. Pristine and modified hollow microparticles were characterized by field-emission electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, FT-IR and Raman spectroscopy, and VSM magnetometry. The potential application of the modified hollow magnetite microspheres as a drug carrier was evaluated by using Rhodamine B and methotrexate as model drugs. The loading and release kinetics of both molecules showed a clear pH and temperature dependent profile. GRAPHICAL ABSTRACT: Hollow magnetite microspheres have been synthesized. Load-release experiments with Rhodamine-B as a model drug and with Methotrexate (chemotherapy drug used in treating certain types of cancer) demonstrated the potential applications of these nanostructures in biomedical applications.     

甘氨酸辅助合成BiOI及其模拟太阳光光催化性能研究

以甘氨酸分子作为模板, 硝酸铋作为铋源, 采用水热合成的方法一步制备了尺寸均一的具有片层花状微球形貌的四方晶相BiOI光催化材料。通过X射线粉末衍射(XRD)、扫描电子显微镜(SEM)、紫外-可见漫反射光谱(UV-Vis/DRS)、N₂吸附-脱附等手段考察了五水硝酸铋与甘氨酸的摩尔比、水热反应时间对BiOI材料形貌、晶相结构及光学吸收等物理化学性质的影响。进一步以罗丹明B和水杨酸为目标污染物对其模拟太阳光光催化性能进行了评价。实验结果显示, 当五水硝酸铋与甘氨酸的摩尔比为1: 2, 水热时间为12 h所合成的BiOI光催化降解活性最高。经40 min模拟太阳光照射后, 罗丹明B和水杨酸的反应速率常数分别达到0.0232和0.0223 min^-1, 与未添加甘氨酸同等条件下合成的BiOI的反应速率常数(0.0111和0.0143 min^-1)相比, 有显著提升。光催化活性提高的主要原因是甘氨酸辅助合成的BiOI材料具有更为规则的形貌和更大的比表面积。     

活性炭吸附水中罗丹明B的研究

采用批量吸附实验,研究了活性炭对水中罗丹明B的吸附行为,探讨了活性炭用量、吸附时间对水中罗丹明B吸附的影响,并对活性炭再生效果进行了测定.结果表明,利用活性炭处理罗丹明B,具有处理效果好、再生容易等特点.运用Langmuir等温吸附方程对其吸附进行了描述,表明吸附属于化学吸附;用准二级吸附动力学方程和准一级吸附动力学方程对实验数据进行了回归分析,准二级吸附动力学方程能更好地描述罗丹明B在活性炭上的吸附.     

疏水改性核壳结构颗粒对Pickering乳液的稳定作用

为了探究固体颗粒对乳液的稳定作用,采用双亲染料分子罗丹明B对核壳结构的Fe_3O_4@SiO_2纳米颗粒进行疏水改性,并将改性后的纳米颗粒作为稳定剂制备Pickering乳液。通过Zeta电位、FTIR、XRD、SEM、接触角测量、光学显微镜、电导率仪对Fe_3O_4@SiO_2纳米颗粒以及Pickering乳液的结构、形貌和性能进行表征与分析,结果表明:制备的纳米颗粒粒径小,约为150 nm,为单分散球形核壳结构;罗丹明B成功修饰到Fe_3O_4@SiO_2纳米颗粒表面,改性后颗粒接触角由30°增加至120°;随乳化剂颗粒质量浓度的增加,制备的乳液液滴的粒径减小。另外,所得Pickering乳液具有良好的磁场响应性,可通过外加磁场实现对乳液稳定性的可逆调控,且此过程可重复3次以上。