首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
TiO2薄膜光催化臭氧化邻苯二酚   总被引:9,自引:1,他引:9  
 研究了用碳黑改性的TiO2薄膜催化剂光催化氧化邻苯二酚的反应.结果表明,臭氧投加量对邻苯二酚的降解和总有机碳(TOC)的去除有重要影响,与光催化氧化(TiO2/UV/O2)、单独臭氧化(O3)和光助臭氧化(UV/O3)过程相比,邻苯二酚光催化臭氧化(TiO2/UV/O3)过程能明显增大TOC的去除率.动力学研究表明,邻苯二酚完全氧化过程遵循零级反应,TOC的降解仅取决于臭氧或氧气的浓度而与邻苯二酚的浓度无关;邻苯二酚在TiO2/UV/O3作用下完全氧化的速率常数是UV/O3作用下的1.32~1.80倍(在相同的臭氧浓度下),是TiO2/UV/O2作用下最大速率常数的2.56~5.36倍,是UV/O2作用下最大速\r\n率常数的5.47~11.4倍.  相似文献   

2.
催化动力学光度法测定发样中痕量铜   总被引:2,自引:0,他引:2  
铜的催化动力学光度法测定研究报道较多,所用的指示剂有偶氮胭红[1]、偶氮胂I[2]、基紫[3]、邻苯二酚紫[4]、番红花红O[5]等.  相似文献   

3.
邻苯二酚和对苯二酚是水体中重要的污染物,对生物体具有严重的危害作用,故实现邻苯二酚与对苯二酚的快速简便、灵敏高效的检测具有十分重要的意义.本文作者综述了近几十年来国内外检测邻苯二酚和对苯二酚的主要方法,如色谱法、分光光度法、化学发光法和电化学分析方法,阐述了各种检测方法的特点;并探讨了两种物质的检测方法的发展趋势.  相似文献   

4.
苯酚在Ln-ZrO_2催化剂上直接氧化制取邻苯二酚的研究   总被引:4,自引:0,他引:4  
以LnZrO2作为苯酚选择氧化催化剂,用过氧化氢氧化,得到邻苯二酚选择性高达857%的良好结果,添加稀土元素镧、钕的氧化锆催化剂与单纯的二氧化钛催化剂相比,邻苯二酚选择性分别提高了735%和678%。  相似文献   

5.
前文报[1]道的硫代磷酰二氯在三乙胺存在下与邻苯二酚反应,不仅具有理论意义,而且是合成该类磷化物的新方法。本文将继续报道硫代磷酰一氯以及其它硫代四配位磷化物与邻苯二酚反应的结果,以期进一步揭示这类反应的本质及其影响因素。  相似文献   

6.
本文报道了6-巯基嘌呤存在时在水相中通过阳极氧化邻苯二酚来电化学合成5-(嘌呤-6-巯基)邻苯二酚衍生物。循环伏安法和控制电位电解的结果表明该类化合物的形成为EC过程,即邻苯二酚衍生物原料先是被电化学氧化成对应的邻苯醌衍生物,该醌非常活泼,进一步与6-巯基嘌呤发生迈克尔加成反应,原位转化生成化合物3a-3d。该工作进一步证明了水相中邻苯醌衍生物的电化学合成与原位转化是合成邻苯二酚衍生物的重要方法。  相似文献   

7.
根据邻苯二酚对Cd Te量子点增敏的Ru(bpy)32+阴极电致化学发光强度有较强的抑制作用,建立了一种简单的测定邻苯二酚的电致化学发光分析方法。分别探究了磷酸盐缓冲溶液的浓度、pH、量子点的浓度、Ru(bpy)_3~(2+)的浓度、扫描速率以及电位等因素对该体系发光行为的影响。在优化实验条件下,电致化学发光强度的对数与邻苯二酚浓度的对数在7.0×10~(-8)~4.0×10~(-5)mol/L范围内呈现良好的线性关系,检出限为2.3×10~(-8)mol/L(3σ)。对4.0×10~(-6)mol/L的邻苯二酚标准溶液进行六次平行测定,其电致化学发光强度的相对标准偏差(RSD)为1.1%。该方法可成功应用于模拟环境水样中邻苯二酚的含量测定,加标回收率介于95.0%~105.7%之间。  相似文献   

8.
梁志结  贾维妮  侍超 《化学研究》2022,33(2):158-163
利用K5[MnV11O32]·(10~12)H2O与漆酶催化邻苯二酚的聚合,并原位用于棉织物染色,分析其聚合产物和棉布样品的红外光谱,以及染色溶液的紫外?可见光谱,探讨钒多酸、漆酶、反应时间等对棉织物染色深度的影响.测试了染色棉织物样品的耐摩擦牢度和耐皂洗牢度.结果表明,多钒氧簇/漆酶体系对邻苯二酚聚合具有优异的催化活...  相似文献   

9.
ZnCl2/NaY催化邻苯二酚与甲醇醚化反应;固体酸催化剂;愈创木酚  相似文献   

10.
以Ln-ZrO2作为苯酚选择氧化催化剂,用过氧化氢氧化,得到邻苯二酚选择性高达85.7%的良好结果,添加稀土元素镧,钕的氧化锆催化剂的单纯的二氧化钛催化剂相比,邻苯二酚选择性分别提高了73.5%和67.8%。  相似文献   

11.
Scandium magnesium gallide, Sc2MgGa2, and yttrium magnesium gallide, Y2MgGa2, were synthesized from the corresponding elements by heating under an argon atmosphere in an induction furnace. These intermetallic compounds crystallize in the tetragonal Mo2FeB2‐type structure. All three crystallographically unique atoms occupy special positions and the site symmetries of (Sc/Y, Ga) and Mg are m2m and 4/m, respectively. The coordinations around Sc/Y, Mg and Ga are pentagonal (Sc/Y), tetragonal (Mg) and triangular (Ga) prisms, with four (Mg) or three (Ga) additional capping atoms leading to the coordination numbers [10], [8+4] and [6+3], respectively. The crystal structure of Sc2MgGa2 was determined from single‐crystal diffraction intensities and the isostructural Y2MgGa2 was identified from powder diffraction data.  相似文献   

12.
13.
On Dialkali Metal Dichalcogenides β-Na2S2, K2S2, α-Rb2S2, β-Rb2S2, K2Se2, Rb2Se2, α-K2Te2, β-K2Te2 and Rb2Te2 The first presentation of pure samples of α- and β-Rb2S2, α- and β-K2Te2, and Rb2Te2 is described. Using single crystals of K2S2 and K2Se2, received by ammonothermal synthesis, the structure of the Na2O2 type and by using single crystals of β-Na2S2 and β-K2Te2 the Li2O2 type structure will be refined. By combined investigations with temperature-dependent Guinier-, neutron diffraction-, thermal analysis, and Raman-spectroscopy the nature of the monotropic phase transition from the Na2O2 type to the Li2O2 type will be explained by means of the examples α-/β-Na2S2 and α-/β-K2Te2. A further case of dimorphic condition as well as the monotropic phase transition of α- and β-Rb2S2 is presented. The existing areas of the structure fields of the dialkali metal dichalcogenides are limited by the model of the polar covalence.  相似文献   

14.
15.
[(n‐Bu)2Sn(O2PPh2)2] ( 1 ), and [Ph2Sn(O2PPh2)2] ( 2 ) have been synthesized by the reactions of R2SnCl2 (R=n‐Bu, Ph) with HO2PPh2 in Methanol. From the reaction of Ph2SnCl2 with diphenylphosphinic acid a third product [PhClSn(O2PPh2)OMe]2 ( 3 ) could be isolated. X‐ray diffraction studies show 1 to crystallize in the monoclinic space group P21/c with a = 1303.7(1) pm, b = 2286.9(2) pm, c = 1063.1(1) pm, β = 94.383(6)°, and Z = 4. 2 crystallizes triclinic in the space group , the cell parameters being a = 1293.2(2) pm, b = 1478.5(4) pm, c = 1507.2(3) pm, α = 98.86(3)°, β = 109.63(2)°, γ = 114.88(2)°, and Z = 2. Both compounds form arrays of eight‐membered rings (SnOPO)2 linked at the tin atoms to form chains of infinite length. The dimer 3 consists of a like ring, in which the tin atoms are bridged by methoxo groups. It crystallizes triclinic in space group with a = 946.4(1) pm, b = 963.7(1) pm, c = 1174.2(1) pm, α = 82.495(6)°, β = 66.451(6)°, γ = 74.922(6)°, and Z = 1 for the dimer. The Raman spectra of 2 and 3 are given and discussed.  相似文献   

16.
17.
Summary The ability of [MoS4]2–, anions to be used as ligands for transition metal ions has been widely demonstrated, especially with Fe2+. The present study has been restricted to linear complexes such as (NEt4)2 [Cl2FeS2MoS2] and (NEt4)2[Cl2FeS2MoS2FeCl2]. Their electrochemical properties are described: upon electrochemical reduction, these compounds yield MoS2, as a black precipitate, and an iron complex in solution, assumed to be [SFeCl2]2–. The electrochemical reduction goes through two electron transfers, coupled with the breakdown of the molecular skeleton: a DISPl and an ECE mechanism. Depending on the solvent, the following equilibrium may be observed: [Cl4Fe2MoS4]2–[Cl2FeMoS4]2–+FeCl2. The equilibrium constant, KD, was evaluated by differential pulse polarography. KD is tightly related to the donor number of the solvent.  相似文献   

18.
Me2Sn(O2PPh2)2 ( 1 ), Ph2Pb(O2PMe2)2 ( 2 ), and Ph2Pb(O2PPh2)2 ( 3 ) have been synthesized by the reactions of Me2SnCl2 or Ph3PbCl with the corresponding diorganophosphinic acid in methanol. X‐ray diffraction studies show that the diorganophosphinate groups behave as double bridges between the metal atoms leading to polymeric ring‐chain structures with M2O4P2 (M = Pb, Sn) eight‐membered rings. The organic groups bonded to the metal atoms are in trans‐position in the resulting octahedral arrangement around the metal atoms. The IR and the mass spectra were reported and discussed.  相似文献   

19.
TG and DTA studies on Me3SnO2PCl2, Me2Sn(O2PCl2)2 and Ph3SnO2PCl2 were carried out under dynamic argon atmosphere. The results show that the decomposition proceeds in different stages leading to the formation of Sn3(PO4)2 as a stable product. This compound was characterized by IR spectroscopy. Decomposition schemes involving reductive elimination reactions were proposed.  相似文献   

20.
The structures of the hypophosphites KH2PO2 (potassium hypophosphite), RbH2PO2 (rubidium hypophosphite) and CsH2PO2 (caesium hypophosphite) have been determined by single‐crystal X‐ray diffraction. The structures consist of layers of alkali cations and hypophosphite anions, with the latter bridging four cations within the same layer. The Rb and Cs hypophosphites are isomorphous.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号