共查询到18条相似文献,搜索用时 187 毫秒
1.
2.
3.
光催化技术能够利用太阳能生成自由基对有机污染物进行矿化降解,具有绿色、节能、无污染的优势,被认为是最有前景的高级氧化技术,目前研究集中于提升光催化技术的降解效率。而采用电场、超声场等外场辅助的方法能够通过提高溶液传质效率、抑制载流子复合、提高自由基产率等途径,进一步提高光催化效率。综述了电场、热场、微波场、超声场、磁场5种外场各自辅助光催化降解有机污染物的研究进展和应用现状,重点介绍了外场提升光催化降解效率的主要机理,归纳了每种外场辅助技术的优缺点,对其在应用中面临的问题进行总结,并对未来研究和发展方向进行了展望。 相似文献
4.
5.
6.
7.
应用Hele-Shaw物理模型和改进的Cross流变模型对辅助射成型过程中充填区域内熔体的流动进行数值模拟,采用控制体积法对充模过程中的熔体前沿、熔体-气体边界进行跟踪,运用有限元/有限差分混合数值方法求解气体注射阶段的速度场、压力场、温度场,以图表的形式列举了不同时刻压力场的分布和充模过程中的流线图。在计算过程中,采用压力场和温度场耦合的方法。 相似文献
8.
赵莉芳 《硫磷设计与粉体工程》2016,(4):32-35,5
大型煤化工项目在生产过程中产生的废渣量较大。对大型合成氨、尿素装置配套设施厂外渣场进行设计,从渣场类别确定、工艺设计、防渗系统、辅助设施等方面确定设计方案,将装置运行所产生的气化废渣和锅炉灰渣均送入渣场的两个分区内贮存,该渣场投运状况良好,符合设计要求。 相似文献
9.
10.
11.
TiO2纳米粒子是一种N型半导体材料,因其具有高活性、稳定性、生物相容性而成为最受重视的一种光催化纳米材料,得到了广泛应用。但由于其存在禁带宽度较大,电子受激发跃迁时产生的电子和空穴十分容易复合等问题,影响光了催化效率,制约着其进一步发展。目前,如何提高TiO2纳米粒子的光催化效率成为材料研究中的热点,是研究的核心课题之一。本文介绍了TiO2纳米粒子的光催化原理,系统综述了TiO2纳米粒子的制备方法;同时总结了提高TiO2纳米粒子光催化效率的方法,并介绍其在生产生活中的应用。 相似文献
12.
从纳滤膜技术、纳米光催化技术、纳米还原性材料及纳米吸附性材料等四个方面介绍了纳米材料与技术在水处理中的应用,并对发展前景进行了展望。 相似文献
13.
14.
Shujian Wang Kejian Lu Anlan Hu Naixu Li Yeti Feng Dengwei Jing Maochang Liu 《American Institute of Chemical Engineers》2022,68(11):e17855
Taking monolithic TiO2/nickel foam as a model photocatalytic material, we hereby report the application of magnetic-photo-thermal coupling field toward enhanced solar photocatalytic hydrogen production. This enhancement is attributed to the increased temperature induced by eddy current effect and effective charge separation caused by the electric field force under the alternating magnetic field condition. Particularly, we demonstrate that a proper set of the position of the monolithic catalyst relative to the reaction solution, that is, at the water-air interface, will lead to a further enhancement of the photocatalytic activity because of the improved mass transfer property of the reactants, with a hydrogen evolution rate of 104.3 μmol h−1. Specifically, the increased temperature of the catalyst leads to the rapid evaporation of water. Hydrogen generation is thus decoupled from liquid water, avoiding kinetically disfavored bubble formation. This work provides a novel strategy to facilitate photocatalytic performance with the application of external field. 相似文献
15.
16.
《无机盐工业》2015,47(6):74
室温沉淀法合成溴氧化铋(BiOBr)纳米片,然后通过离子交换法制备溴化银/溴氧化铋(AgBr/BiOBr)复合纳米材料,采用X射线衍射(XRD)、场发射扫描电子显微镜(FE-SEM)及紫外可见分光光度计(UV-Vis)对其进行表征,并进行了光催化降解实验。以节能、绿色的LED灯为可见光光源,AgBr/BiOBr复合材料光催化降解罗丹明B(RhB)和甲基橙(MO)的效率均高于BiOBr。AgBr/BiOBr降解RhB的活性强于MO。在AgBr/BiOBr光催化系统中,超氧自由基和空穴是主要的活性物种。不同pH条件下,AgBr/BiOBr对RhB均表现出理想的光催化降解效果,酸性条件下降解效率最佳;碱性环境下AgBr/BiOBr光催化降解MO的活性最高。经过循环利用,AgBr/BiOBr可见光催化活性呈现出一定程度的降低,归因于降解过程中产生了金属银。 相似文献
17.
A magnetically separable photocatalyst TiO2/SiO2/NiFe2O4 (TSN) with a typical ferromagnetic hysteresis was prepared by a liquid catalytic phase transfer method. When the intensity of applied magnetic field weakened to zero, the remnant magnetism of the prepared photocatalyst faded to zero. The photocatalytst can be separated from water when an external magnetic field is added and redispersed into aqueous solution after the external magnetic field is eliminated, that makes the photocatalysts promising for wastewater treatment. Transmission electron microscope (TEM) and X-ray diffractometer (XRD) were used to characterize the structure of the photocatalyst indicating that the magnetic SiOffNiFe204 (SN) particle was compactly enveloped by P-25 titania and Tit2 shell was formed. The magnetic composite showed high photocatalytic activity for the degradation of methyl orange in water. A thin SiO2 layer between NiFe2O4 and TiO2 shell prevented effectively the leakage of charges from TiO2 particles to NiFe2O4, which gave rise to the increase in photocatalytic activity. Moreover, the experiment on recycled use of TSN demonstrated a good repeatability of the photocatalytic activity. 相似文献