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141.
以硝酸银、钛酸四丁酯、无水氯化锌、六水氯化铁为原料,采用溶胶-凝胶法与溶剂热相结合的方法制备了ZnFe2O4/Ag/TiO2复合材料,通过扫描电子显微镜、能谱分析仪、X射线粉末衍射仪、X射线光电子能谱仪、振动样品磁强计、紫外可见分光光度计对样品进行表征及测试。结果表明:ZnFe2O4/Ag/TiO2-10具有最佳的光催化效果,在紫外和可见光下对染料的降解率都能达到90%以上,具有优异的紫外可见光光催化活性。ZnFe2O4/Ag/TiO2具有独特的磁性,能在外部磁场作用下进行回收利用,这使其在实际应用中成为可能。通过磁分离技术重复回收利用5次后仍然保持优良的光催化性能,说明ZnFe2O4/Ag/TiO2-10具有优异的磁性及较高的光催化循环稳定性。 相似文献
142.
采用简单的溶剂热法制备出具有孪晶结构的红细胞状硫化铜材料。研究不同前驱体比例和反应时间对硫化铜产物微观形貌的影响,并对孪晶结构红细胞状硫化铜可能的形成机理进行分析。在可见光照射下孪晶结构红细胞状硫化铜与H2O2组成的类芬顿系统表现出优异的降解性能,光照50 min后,亚甲蓝降解率可达95%。对比孪晶结构红细胞状硫化铜与合成的花球状硫化铜的催化性能,结果表明含有孪晶结构的红细胞状硫化铜对亚甲蓝的降解性能更好,说明孪晶的存在有利于加速光生电子-空穴的分离。 相似文献
143.
Mohammadamin Ezazi Qiang Ye Anil Misra Candan Tamerler Paulette Spencer 《Molecules (Basel, Switzerland)》2022,27(17)
The low-viscosity adhesive that is used to bond composite restorative materials to the tooth is readily damaged by acids, enzymes, and oral fluids. Bacteria infiltrate the resulting gaps at the composite/tooth interface, demineralize the tooth, and further erode the adhesive. This paper presents the preparation and characterization of a low-crosslink-density hydrophilic adhesive that capitalizes on sol-gel reactions and free-radical polymerization to resist hydrolysis and provide enhanced mechanical properties in wet environments. Polymerization behavior, water sorption, and leachates were investigated. Dynamic mechanical analyses (DMA) were conducted using water-saturated adhesives to mimic load transfer in wet conditions. Data from all tests were analyzed using appropriate statistical tests (α = 0.05). The degree of conversion was comparable for experimental and control adhesives at 88.3 and 84.3%, respectively. HEMA leachate was significantly lower for the experimental (2.9 wt%) compared to control (7.2 wt%). After 3 days of aqueous aging, the storage and rubbery moduli and the glass transition temperature of the experimental adhesive (57.5MPa, 12.8MPa, and 38.7 °C, respectively) were significantly higher than control (7.4MPa, 4.3 MPa, and 25.9 °C, respectively). The results indicated that the autonomic sol-gel reaction continues in the wet environment, leading to intrinsic reinforcement of the polymer network, improved hydrolytic stability, and enhanced mechanical properties. 相似文献
144.
Elizabeth Rojas-García Diana Carolina García-Martínez Ricardo Lpez-Medina Fernando Rubio-Marcos Aldo A. Castaeda-Ramírez Ana M. Maubert-Franco 《Molecules (Basel, Switzerland)》2022,27(20)
Composite materials based on titania nanoparticles (TiO2 NPs) and three metal-organic frameworks (MOFs) called MIL-53 (Fe) ((Fe (III) (OH) (1,4-BDC)), MILs (Materials Institute Lavoisier)), MIL-100 (Fe) (Fe3O(H2O)2OH(BTC)2), and Fe-BTC (iron-benzenetricarboxylate) with different percentages of TiO2 NPs (0.5, 1, and 2.5% wt.) were synthesized using the solvothermal method and used as photocatalytic materials in the degradation of two dyes (Orange II and Reactive Black 5 (RB5)). The pristine and composite materials were characterized with X-ray diffraction, Raman, UV–Vis and Fourier transform infrared spectroscopy and scanning electron microscopy techniques. The 2.5TiO2/MIL-100 composite material showed the best results for the degradation of both dyes (Reactive Black 5 and Orange II dye, 99% and 99.5% degradation in 105 and 150 min, respectively). The incorporation of TiO2 NPs into MOFs can decrease the recombination of the change carrier in the MOF, increasing the photocatalytic activity of a pristine MOF. Results therefore indicated that the synthesized MOF nanocomposites have good potential for wastewater treatment. 相似文献
145.
Dan-Dan Ren Xiaoyan Lu Li-Ping Zhou Huanghongjun Tian Shuang Wang Lu-Fang Ma Dong-Sheng Li 《Molecules (Basel, Switzerland)》2022,27(22)
Organic dyes are widely used in the textile, biological, medical and other fields. However, a serious environmental problem has appeared because of the presence of organic dyes in industrial aqueous effluents. Thus, the efficient treatment of organic dyes in industrial wastewaters is currently in real demand. The current study investigated the oxidative degradation of the organic dye gentian violet by meso-tetra(carboxyphenyl) porphyriniron(III), [FeIII(TCPP)] as a cytochrome P450 model and iodosylbenzene (PhIO) as an oxidant at room temperature. The degradation reaction was monitored by UV–vis absorption spectroscopy via the observation of UV–vis spectral changes of the gentian violet. The results showed that the efficiency of catalyzed degradation reached more than 90% in 1 h, indicating the remarkable oxidative degradation capacity of the [FeIII(TCPP)]/PhIO system, which provided an efficient approach for the treatment of dyeing wastewater. 相似文献
146.
Anam Safri Ashleigh Jane Fletcher Ramsha Safri Hifza Rasheed 《Molecules (Basel, Switzerland)》2022,27(23)
Recent studies on the removal of pollutants via adsorption include the use of carbon-based adsorbents, due to their high porosity and large surface area; however, such materials lack photoactive properties. This study evaluates the synergistic effect of integrated mesoporous carbon xerogel (derived from resorcinol formaldehyde) and titanium dioxide (TiO2) for combined adsorption and photodegradation application. The complex formed between carbon xerogel and TiO2 phase was investigated through FTIR, proving the presence of a Ti-O–C chemical linkage. The physicochemical properties of the synthesised adsorbent–photocatalyst were probed using FESEM, BET analysis and UV–Vis analysis. The kinetics, equilibrium adsorption, effect of pH, and effect of adsorbent dosage were investigated. The expansion of the absorbance range to the visible range was verified, and the corresponding band gap evaluated. These properties enabled a visible light response when the system was exposed to visible light post adsorption. Hence, an assistive adsorption–photodegradation phenomenon was successfully executed. The adsorption performance exhibited 85% dye degradation which improved to 99% following photodegradation. Further experiments showed the reduction of microorganisms under visible light, where no microbial colonies were observed after treatment, indicating the potential application of these composite materials. 相似文献
147.
水热合成法制备了不同磁性纳米洋葱碳(MCNOs)负载量(0%、1%、3%、5%)的MCNOs/CdS光催化剂。并通过X射线衍射分析(XRD)、扫描电子显微镜(SEM)、傅里叶红外光谱(FT-IR)、X射线光电子能谱(XPS)、紫外可见光光谱(UV-Vis)、磁滞回线测定仪(VSM)对其进行表征,探究了MCNOs负载比例对催化剂在可见光下降解RhB性能及机理的影响。结果表明,MCNOs能有效提高CdS的光催化效果,复合3%MCNOs后降解率为96%,与纯CdS相比降解率提高了30%,磁性分析表明,其具有良好的顺磁性并能实现催化剂的有效回收。MCNOs/CdS在可见光下催化降解RhB的一级反应动力学直线有较好的拟合度,表明制备的催化剂有较好的催化活性。 相似文献
148.
BixOyBrz光催化剂在有机药物废水处理领域有着非常广阔的潜在应用价值,但因光生电子和空穴的快速复合而表现出较低的光催化效率,进而限制了其应用范围。通过简易的水解-焙烧法原位制得一种新型的Bi3O4Br/Bi12O17Br2复合光催化剂,并以磺胺甲噁唑(SMX)为模拟药物污染物进行了光催化性能测试,对所制催化剂进行了X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、紫外可见漫反射光谱(UV-Vis DRS)、电化学阻抗(EIS)、光致发光光谱(PL)等表征。结果表明所制备的Bi3O4Br/Bi12O17Br2复合光催化剂具有较强的光生载流子分离率、较低的界面电荷转移电阻,进而展示出优异的光催化降解SMX性能,在模拟太阳光下照射30 min,SMX降解率达到87%,相较于纯的Bi3O4Br和Bi12O17Br2催化剂,降解率分别提升了30%和24%。最后基于自由基捕获实验和催化剂能带结构分析了所制催化剂的降解机理。 相似文献
149.
Preparation,Characterization,and in vitro Release of Biodegradable Erythromycin-gelatin Microspheres
Blank and erythromycin-loaded gelatin microspheres were successfully fabricated via emulsion chemical- crosslinking technique. The surface morphology of the microspheres was characterized by scanning electron microscope(SEM) and optical microscope. The results show that the microspheres were spherical and smooth. The particle average size of erythromycin-loaded microspheres was found to be 20.6 μm, with a high purity of more than 90% and with a good dispersibility. The microspheres could be obtained in a high yield. Erythromycin released from the microspheres was monitored in buffer and artificial body fluid at 37 ℃. Average drug content was 27.2%, and erythromycin-loaded gelatin microspheres showed good release profiles with a nearly constant release during 4-8 h in artificial body fluid in vitro degradation studies. These gelatin microspheres are useful for studying and developing various drug-delivery systems. 相似文献
150.
油田污水中聚丙烯酰胺(HPAM)的降解机理研究 总被引:9,自引:0,他引:9
随着聚合物驱油技术在我国油田的大面积推广,含聚丙烯酰胺污水的产量在逐年增加 .聚丙烯酰胺在为油田生产提高原油采收率的同时,也大幅度增加了混合液的粘度和乳化性 ,使油水分离难度加大,造成采出水含油量严重超标.含聚丙烯酰胺污水具有粘度高、油水分离难度大、可生化性差等特点,对环境的负面影响也越来越明显.因此,亟待解决的问题便是部分水解聚丙烯酰胺的降解.本文综述了聚丙烯酰胺化学、生物降解机理,总结了降解聚丙烯酰胺的典型的微生物种群,阐述了生物方法的优势,为油田含聚丙烯酰胺污水的处理研究提供参考. 相似文献