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研究了用离子交换沉淀法制备的Ag/Ag3PO4/g-C3N4的可见光光催化性能及再生方法.通过X射线衍射(XRD)、场发射扫描电子显微镜(FESEM)、紫外-可见(UV-Vis)吸收光谱及X射线光电子能谱(XPS)对其进行了结构特性分析.XRD结果显示再生后催化剂的结构未发生改变.FESEM及UV-Vis分析结果说明催化剂由Ag3PO4与g-C3N4复合而成.XPS分析结果表明催化剂表面出现少量的银单质.利用可见光(λ420nm)照射下的苯酚降解实验评价了样品的光催化活性,并通过活性物种及能带结构的分析对催化剂的光催化机理进行了推测.研究表明,Ag/Ag3PO4/g-C3N4的光催化活性明显高于纯Ag3PO4及纯g-C3N4,主要原因归结为单质银、Ag3PO4及g-C3N4的协同效应.经过氧化氢和磷酸氢铵钠(NaNH4HPO4)的再生可完全恢复催化剂的活性,这表明该绿色环保的再生方法可实现Ag/Ag3PO4/g-C3N4催化剂在环境中的实际应用. 相似文献
73.
The syntheses of three new optically active β-mercaptoalcohols,(R)-1,1-diphenyl-2-mercapto-3-methyl-1-butanol,(R)-1,1-diphenyl-2-mercapto-4-methyl-1-pentanol,and (R)-1,1-diphenyl-2-mercapto-1-benzenepropanol from the corresponding amino acids are described.The enantiomeric excesses of these β-mercaptoalcohols were determined by ^1H NMR as their (S)-mandeloyl derivatives. 相似文献
74.
Wang YW Liu WS Tang N Tan MY 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(11):2459-2463
Solid complexes of lanthanide picrates with N,N-dibenzyl-2-[2'-[(dibenzylcarbamoyl)-methoxy]-[1,1']binaphthalenyl-2-yloxy]-acetamide (L), [Ln(pic)(3)L] (Ln = La, Nd, Eu, Gd, Tb, Dy, Y), have been prepared and characterized by elemental analysis, IR, 1H NMR, UV-Vis spectra and conductivity measurements. The fluorescence property of the europium complex in solid state and in CHCl(3), acetone, AcOEt and DMF was studied. 相似文献
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76.
Chen SW Zhang YL Dou W Wang YW Liu WS 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,62(4-5):826-830
Four ligands 1,10-phenanthroline-5,6-bis(N,N-dibenzyl-1′-oxopropylamide) (La) 1,10-phenanthroline-5,6-bis(N-methyl-N-benzyl-1′-oxopropylamide) (Lb) 1,10-phenanthroline-5,6-bis(N-benzyl-1′-oxopropylamide) (Lc) and 1,10-phenanthroline-5,6-bis(N,N-diethyl-1′-oxopropylamide) (Ld), and their lanthanide(III) (La and Eu) complexes were synthesized. The complexes were characterized by elemental analysis, IR, fluorescence spectroscopy and conductivity. The lanthanide atoms are coordinated by O atoms from C=O, Ar–O –C and N atoms from phen With the difference of the ligands, the fluorescent intensities of the Eu(III) complexes vary regularly in the THF solution. Some factors that influence the fluorescent intensity were discussed. 相似文献
77.
(R)-2-{[4-(3-甲氧基丙氧基)-3-甲基吡啶-2-基]甲基亚硫酰基}- 1H-苯并咪唑的合成 总被引:1,自引:0,他引:1
以2,3-二甲基吡啶为起始原料, 经过11步反应, 不对称合成了质子泵抑制剂的关键中间体: (R)-2-{[4-(3-甲氧基丙氧基)-3-甲基吡啶-2-基]甲基亚硫酰基}-1H-苯并咪唑. 研究了用手性高效液相色谱拆分对映体、测定产品光学纯度的方法, 结果表明目标产品的ee值达到99%. 通过IR, UV, MS以及1H NMR分析对重要中间体和目标产品进行了结构鉴定. 相似文献
78.
Zhou HP Zhang YW Mai HX Sun X Liu Q Song WG Yan CH 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(11):3380-3390
Uniform CeO(2) nanoflowers were synthesized by rapid thermolysis of (NH(4))(2)Ce(NO(3))(6) in oleic acid (OA)/oleylamine (OM), by a unique 3D oriented-attachment mechanism. CeO(2) nanoflowers with controlled shape (cubic, four-petaled, and starlike) and tunable size (10-40 nm) were obtained by adjusting the reaction conditions including solvent composition, precursor concentration, reaction temperature, and reaction time. The nanoflower growth mechanism was investigated by in situ electrical conductance measurements, transmission electron microscopy, and UV/Vis spectroscopy. The CeO(2) nanoflowers are likely formed in two major steps, that is, initial formation of ceria cluster particles capped with various ligands (e.g., OA, OM, and NO(3) (-)) via hydrolysis of (NH(4))(2)Ce(NO(3))(6) at temperatures in the range 140-220 degrees C, and subsequent spontaneous organization of the primary particles into nanoflowers by 3D oriented attachment, due to a rapid decrease in surface ligand coverage caused by sudden decomposition of the precursor at temperatures above 220 degrees C in a strong redox reaction. After calcination at 400 degrees C for 4 h the 33.8 nm CeO(2) nanoflowers have a specific surface area as large as 156 m(2) g(-1) with high porosity, and they are highly active for conversion of CO to CO(2) in the low temperature range of 200-400 degrees C. The present approach has also been extended to the preparation of other transition metal oxide (CoO, NiO, and CuO(x)) nanoflowers. 相似文献
79.
Four new complexes have been synthesized based on the 2,4,5-trifluoro-3-methoxybenzoic acid and 4,4′-bipy of the type [R3Sn(OOCC6HF3OCH3)]2·(4,4′-bpy). All complexes were characterized by elemental, IR, 1H, 13C and 119Sn NMR spectra analyses. Complexes 1 and 4 were also characterized by X-ray crystallography. Crystal structures of 1 and 4 show that the coordination number of tin atom is five and the 2D network is connected by intermolecular C–H···O interactions. 相似文献
80.