Fe掺杂TiO2和Fe2O3量子点共负载催化剂:吸附与光催化协同作用高效降解有机染料

光催化作为节能、清洁的环境处理技术,被广泛应用于污染物处理领域,如室内气体净化、尾气VOCs处理和水体有机污染降解等.在众多光催化剂中,TiO2以其良好的化学稳定性、无二次污染、无刺激性和安全无毒等优势得到广泛研究.然而TiO2是宽禁带材料,仅能吸收太阳光谱的紫外光部分,通常需要用紫外光源来激发,光生电子-空穴易复合,这限制了其应用.过渡金属离子掺杂能在TiO2价带之上形成新的掺杂能级,从而提高其光谱响应范围,提高全光谱反应活性; 与体相TiO2相比,纳米尺寸的TiO2具有更高的光催化活性,尤其小于10 nm的量子点尺寸TiO2有着高活性面积、较短的光生电子-空穴迁移路径和独特的量子尺寸效应; Fe2O3作为吸附材料与TiO2构建复合材料能够发挥吸附与光催化协同作用,从而提高污染物处理效率.我们以构建Fe掺杂TiO2和Fe2O3量子点共负载催化剂为目标,以钛酸四丁酯(TBT)和硫酸亚铁为前驱体,采用常温水解方法将Fe掺杂的TiO2量子点生长在MCM-41分子筛表面,并通过调节硫酸亚铁加入量合成了MCM-41负载的Fe掺杂TiO2和Fe2O3量子点催化剂.采用透射电子显微镜和X射线衍射研究了复合晶体结构,采用X射线光电子能谱、紫外-可见光谱和傅里叶变换红外光谱等表征手段研究了复合量子点材料生长机理和能带结构.结合吸附过程和光降解过程建立了吸附与光催化协同作用与污染物处理效率之间的关联关系.表征结果表明,硫酸亚铁水溶液加速TBT水解成功地在MCM-41表面生长了Fe掺杂TiO2量子点,并且量子点粒径随Fe前驱体量的增加而变大; 前驱体比例Ti/Fe ≤ 3.0时,过量的硫酸亚铁会析出并在焙烧过程中在MCM-41上分解为Fe2O3量子点,Fe2O3量随着硫酸亚铁加入量提高而增多.通过调节Fe前驱体的量,一方面Fe掺杂在二氧化钛价带之上形成了掺杂能级,减小了带隙,拓宽了光响应范围,另一方面引入适量Fe2O3量子点,实现了Fe掺杂TiO2和Fe2O3量子点共负载催化剂的构建.复合材料实现了吸附过程与光催化降解过程的协同作用,Fe2O3将污染物富集于催化剂表面,Fe掺杂TiO2将其有效降解,大大提高了污染物处理能力,其中FT/M-3.0处理效率最高,并在10次循环处理后依然维持较高的吸附能力和光催化降解能力.该工作为高效光催化水处理催化剂的设计和构建提供了新思路和策略.     

异戊二烯催化脱氢环氧化的研究

 合成了钼－乙酰丙酮配合物，并进行了表征，确定了其组成为M\r\noO2（acac）2．以MoO2（acac）2为催化剂，以过氧化氢为氧化剂，对\r\n异戊二烯一步脱氢环氧化制3－甲基呋喃反应进行了研究．考察了反应\r\n条件（催化剂用量、反应底物之比、温度、时间、溶剂和助剂等）对该\r\n反应的影响．结果表明，在n（cat）∶n（CH2∶C（CH3）CH∶CH2）∶\r\nn（H2O2）＝1∶100∶100，θ＝40℃，t＝6h的反应条件下，异戊二烯\r\n转化率为70．8％，3－甲基呋喃选择性为54．8％．提出了异戊二烯脱\r\n氢环氧化可能的反应机理．     

The Synthesis of l-Ethyl-1''''-(4-vinylbenzyl)-4, 4''''-bipyridinium Chloride and Iodide and its Electrochromic Property

A new compound 1-ethyl-1'-(4-vinylbenzyl)-4, 4'-bipyridinium chloride and iodide has been synthesized. The cyclic voltammogram and impedance spectra indicated that a layer of viologen's electrochromic (EC) film could be deposited on conductive ITO glass working electrode. With polyelectrolyte as ionic conduction layer, solid EC devices based on this compound have been assembled and their thickness was about 2.35 mm. When different voltages were added, they showed blue or violet red color. After optimization, its response time was less than 50 ms, the number of redox circulation was over 107 and the color of coloration states could be kept for 3 days. This kind of EC device can meet the demand of electronic ink.     

An atomic electronegative distance vector and carbon-13 nuclear magnetic resonance chemical shifts of alcohols and alkanes

A novel atomic electronegative distance vector (AEDV) has been developed to express the chemical environment of various chemically equivalent carbon atoms in alcohols and alkanes. Combining AEDV and Y parameter, four five-parameter linear relationship equations of chemical shift for four types of carbon atoms are created by using multiple linear regression. Correlation coefficients are R = 0.9887, 0.9972, 0.9978 and 0.9968 and roots of mean square error are RMS = 0.906, 0. 821, 1.091 and 1.091 of four types of carbons, i.e., type 1, 2, 3, and 4 for primary, secondary, tertiary, and quaternary carbons, respectively. The stability and prediction capacity for external samples of four models have been tested by cross-validation.     

Resonance Rayleigh Scattering Spectra of Thorium(IV)-bisazo Dye of Chromotropic Acidprotein Systems and Their Analytical Applications

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｐｒｏｔｅｉｎｓｉｓｉｍｐｏｒｔａｎｔｉｎｂｉｏｃｈｅｍｉｃａｌｓｔｕｄｙ ,ｃｌｉｎｉｃａｌｔｒｅａｔｍｅｎｔａｎｄｆｏｏｄａｎａｌｙｓｉｓ .Ａｓｉｔｉｓｋｎｏｗｎ ,ｔｈｅｃｏｍｍｏｎｍｅｔｈｏｄｓｕｓｅｄｔｏｄｅｔｅｒｍｉｎｅｔｈｅｐｒｏｔｅｉｎｑｕａｎｔｉｔａ ｔｉｖｅｌｙａｔｐｒｅｓｅｎｔａｒｅｓｐｅｃｔｒｏｐｈｏｔｏｍｅｔｒｙａｎｄｆｌｕｏｒｏｓｐｅｃ ｔｒｏｐｈｏｔｏｍｅｔｒｙ.1Ｒｅｃｅｎｔｌｙ ,ｒｅｓｏｎａｎｃｅＲａｙｌｅｉｇ…     

On Ekeland's Variational Principle for Set-Valued Mappings

In this paper,we derive a general vector Ekeland variational principle for set-valued mappings,which has a closed relation to εk~O-efficient points of set-valued optimization problems.The main result presentedin this paper is a generalization of the corresponding result in[3].     

Thermally assisted switching in FePt single-domain particles with a Gaussian distribution of temperature

Magnetic nanoscale systems,including nanodots,nanofibers,nanowires and nanoparticles,are currently attracting great interest due to their interesting physical and promising applications in various fields,such as magnetic recording,sensors,target drugs and catalysts,as well as others.To achieve ultrahigh recording density,the method of heat assisted magnetic recording(HAMR) has been introduced.In this work,with the help of a Monte Carlo method,the mechanisms of thermally assisted magnetization switching in F...     

分光光度法测定人工晶状体中清洗剂磺基琥珀酸二辛酯钠残留

建立分光光度法分析眼科植入物人工晶体中清洗剂磺基琥珀酸二辛酯钠残留的方法。磺基琥珀酸二辛酯在酸性水溶液介质中与亚甲基蓝形成离子对,用三氯甲烷提取并在651 nm波长处测定其吸光度。磺基琥珀酸二辛酯钠的质量浓度在1.0~5.0μg/m L内与吸光度呈良好的线性关系,线性相关系数r~2=0.990 1,检出限为0.4μg/m L。测定结果的相对标准偏差为1.21%(n=6),日间重复性为2.06%(n=6);加标回收率为90%~97%。该方法检出限低,再现性好,适用于人工晶状体中磺基琥珀酸二辛酯钠残留量的测定。     

The influence of X-semipermutability of subgroups on the structure of finite groups

Let A be a subgroup of a group G and X be a nonempty subset of G. A is said to be X-semipermutable in G if A has a supplement T in G such that A is X-permutable with every subgroup of T. In this paper, we investigate further the influence of X-semipermutability of some subgroups on the structure of finite groups. Some new criteria for a group G to be supersoluble or p-nilpotent are obtained.     

LEVITIN-POYAK WELL-POSEDNESS OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS WITH FUNCTIONAL CONSTRAINTS

In this article, we study Levitin-Polyak type well-posedness for generalized vector equilibrium problems with abstract and functional constraints. Criteria and characterizations for these types of well-posednesses are given.