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Two Cobalt(II) Complexes Derived from the Hydrolysis Product of Di-Schiff Base Ligand N,N'-Bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine:Preparation,Characterization and Crystal Structure of the 6-Coordinate Species [CoL_2]X·H_2O (X = ClO_4^-, N 被引量:1
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作者 夏昌坤 吴小园 +2 位作者 吴鼎铭 蒋晓瑜 卢灿忠 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第7期805-811,共7页
The reactions of Co(C1O4)2·6H2O and Co(NO3)2.6H2O with the di-Schiff base ligand N,N'-bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine (LA) in ethanol have been investigated. The reactions of LA wi... The reactions of Co(C1O4)2·6H2O and Co(NO3)2.6H2O with the di-Schiff base ligand N,N'-bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine (LA) in ethanol have been investigated. The reactions of LA with excess amount of cobalt salts yield the six-coordinate complexes [CoL2](ClO4)E·H2O 1 and [CoL2](NO3)E·H2O 2 as isolatable products (L= N-(1- benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine), where L is a tri-dentate mono-Schiff base ligand, resulting from the hydrolysis of the precursor di-Schiff base LA. Both complexes were characterized by X-ray crystallography. Crystal data for complex 1: monoclinic, space group P21/c, a = 11.9214(10), b = 23.5828(17), c = 14.0387(12)A, β = 135.219(4)°, C22H30Cl2CoN8O9, Mr = 680.37, V = 2780.1(4) A^3 ,Z = 4, Dc = 1.625 g/cm^3,μ(MoKa) = 0.876 mm^-1, F(000) = 1404, the final R = 0.0725 and wR = 0.1530 for 5726 observed reflections (I 〉 2σ(I)). Crystal data for complex 2: monoclinic, space group P21/c, a = 18.2162(16), b = 10.0610(6), c = 18.593(2)A, β = 130.099(3)°, C22H30CoN10O7, Mr = 605.49, V = 2606.5(4) A3 Z = 4, Dc = 1.543 g/cm^3,μ(MoKa) = 0.722 mm^-1, F(000) = 1260, the final R = 0.0619 and wR = 0.1429 for 5194 observed reflections (I 〉 2σ(I)). X-ray diffraction analysis reveals that each cobalt atom in the two complexes is chelated by six nitrogen atoms from two tridentate iigands L, exhibiting a slightly distorted octahedral coordination sphere. In both complexes, the strong hydrogen-bonding interactions between the lattice waters and N-H groups of the ligands result in 1D chains which are further connected by ClO4^- (or NO3^-) groups to form a 3D framework. In complex 2, the strong π-π interactions increase the stability of the structure. 展开更多
关键词 2-acetylbenzimidazole di-Schiff base ligand crystal structure hydrolysis hydrogen-bonding interactions coordination complex n n -bis-(1-benzimidazo-2-yl-ethylidene)-ethane- 1 2-diamine n-(1-benzimidazo-2-yl-ethylidene)-ethane- 1 2-diamine
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Identification of N-Methyl Bis(2-(Alkyloxy-Alkylphosphoryloxy)Ethyl) Amines by LC-HRMS/MS
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作者 Huilan Yu Shilei Liu +2 位作者 Daoming Sun Chengxin Pei Yu Xiang 《American Journal of Analytical Chemistry》 2014年第13期820-827,共8页
N-Methyl bis(2-(alkyloxy-alkylphosphoryloxy)ethyl)amines, which are abbreviated as PNPs, are a series of new skeleton chemicals belonging to schedule 2.B.04 chemicals of Chemical Weapons Convention (CWC). PNPs are imp... N-Methyl bis(2-(alkyloxy-alkylphosphoryloxy)ethyl)amines, which are abbreviated as PNPs, are a series of new skeleton chemicals belonging to schedule 2.B.04 chemicals of Chemical Weapons Convention (CWC). PNPs are important markers of chemical warfare agents because they are structurally relative to both nerve agents and N-mustards. In this study, fragmentation pathways of the most characteristic fragment ions in Q-TOF mass spectrometry were proposed based on the information from accurate mass and secondary fragmentations of product ions scan experiments. Results indicated that the base ion in LC/HRMS was the quasi-molecular ion [M+H]+. In LC-HRMS/MS, it was [M+H-CnH2n+1P(O)(OH)CmH2m+1O]+ fragment ion which was formed by losing an alkyloxy alkylphosphoryloxy group from the quasi-molecular ion. The diagnostic ion m/z84.0814 was identified as [C5H10N]+, which was the group of (CH2=CH)2N+(H)CH3. PNPs have two protonated centers. One is on the N atom, the other is on the O atom (P=O). O-n-propyl PNPs generally exhibited two fragmentation pathways. Firstly, the quasi-molecular ion [M+H]+ lost a propoxy alkylphosphoryloxy group to produce [R1P(OH+)(O-n-C3H7)OCH2CH2N(CH3)CH=CH2]+, which could be fragmented further to produce [C5H10N]+ ion. Secondly, [R1P(OH+)(O-n-C3H7) OCH=CH2]+ ions were produced from [M+H]+ and fragmented further to produce the abundant ions [R1P(OH+)(OH)OCH =CH2]. However, O-isopropyl PNPs characteristically produced weak fragment ions [M+H-C3H6]+, which were presumably formed via loss of CH3CH=CH2 from [M+H]+. Other PNPs showed similar fragmentation pathways as O-n-propyl PNPs. On the summarization of the MS fragmentation pathways of PNPs, LC-HRMS/MS quantitative and qualitative methods were developed and applied to analyze N-Methyl bis(2-(butoxy-methylphosphoryloxy)ethyl]amine in high background organic samples. The analytical results had successfully supported the sample preparation for the 33rd official proficiency test of Organization for Prohibition of Chemical Weapons (OPCW). 展开更多
关键词 Chemical Weapons LC-HRMS/MS n-Methyl bis(2-(Alkyloxy-Alkylphosphoryloxy)Ethyl)Amines Fragmentation Pathways Analysis
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Crystal and Molecular Structure of Bis-N,N’(dithiodi-2,1-phennylene)benzamide 被引量:2
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作者 JI Ming Juan ZHAO Zhu Liu YAN Da Yu (Graduate School of University of Science and Technology of China, Beijing, 100039) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第2期75-78,共4页
The crystal structure of the title compound ((C 6H 5CONC 6H 4S) 2, M r =229) has been determined by X ray diffraction analysis. The crystal belongs to triclinic space group P 1 with cell parameters: a=... The crystal structure of the title compound ((C 6H 5CONC 6H 4S) 2, M r =229) has been determined by X ray diffraction analysis. The crystal belongs to triclinic space group P 1 with cell parameters: a=7.957(4), b=11.570(7), c=12 335(6), α=76.68(4), β=81.48(4), γ=87.26(4)°, V=1092.9 3, Z=2, D c =1 39g/cm 3, F(000)=476, μ (Mo Kα )=2.7mm -1 . The final R factor is 0.0373 for 3764 observed reflections. The result of X ray diffraction analysis indicates that all of these single bond lengths are obviously shorter than that of standard single bond. Those atoms might take part in a conjugate system. The electrons for sp 3 hybridized S(1) and S(2) move toward two sides and the densities of electronic cloud among them are reduced and can be easily broken. The obtained results can explain the reaction mechanism of the title compound. 展开更多
关键词 bis n n (dithiodi 2 1 phennylene)benzamide crystal structure molecular structure conformation analysis
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One-Pot Synthesis of N-Boc-2, 5-bis(trimethylsilyl)pyrrolidine
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作者 Dong, JC Li, RT Cheng, TM 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第12期1061-1064,共4页
N-Boc-2, 5-bis(trimethylsilyl)pyrrolidine 4 was synthesized from the reaction of N-Boc-pyrrolidine 1 with trimethylsilyl chloride (TMSCl) at optional temperature in one-pot in good yield.
关键词 n-Boc-2 5-bis(trimethylsilyl)pyrrolidine TRIMETHYLSILYLATIOn OnE-POT
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Synthesis of 1, 4-Bis[3-N-propionyl-2-aryl-1, 3, 4- oxadiazoline-5-yl]phenylenes
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作者 De Jiang LI He Qing FU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第5期625-627,共3页
1, 4-Bis[3-N-propionyl-2-aryl-1, 3, 4-oxadiazoline-5-yl]phenylenes 4 were synthesized by cyclization of corresponding hydrazones 3 with propionic anhydride.
关键词 1 4-bis[3-n-propionyl-2-aryl-1 3 4-oxadiazoline-5-yl]phenylenes hydrazones terephthaloyldihydrazine synthesis.
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Synthesis and Potential Application of Novel C_(2)-Symmetrical Bis(ferrocenyl)P2N Ligand
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作者 Xiang Ping HU Hui Lin CHEN +2 位作者 Hui Cong DAI Xin Quan HU Zhuo ZHENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第11期1113-1115,共3页
A novel chiral bis(ferrocenyl) P2N ligand 1 with C2-symmetry was synthesized through a four-step procedure from (R)-N,N-dimethyl-1-ferrocenylethylamine. In a model reaction of Pd-catalyzed allylic alkylation of 1,3-d... A novel chiral bis(ferrocenyl) P2N ligand 1 with C2-symmetry was synthesized through a four-step procedure from (R)-N,N-dimethyl-1-ferrocenylethylamine. In a model reaction of Pd-catalyzed allylic alkylation of 1,3-diphenylprop-2-enyl acetate 6 with dimethyl malonate, good enantioselectivity (86% e.e.) was obtained. 展开更多
关键词 SYnTHESIS C_(2)-symmetry bis(ferrocenyl) P2n ligand Pd-catalyzed allylic alkylation.
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Synthesis and Structure of Zinc Complex of N, N-bis ( benzimidazol-2-yl-methyl ) amine
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作者 Xiao Lan LIU Qing Yan CHENG +3 位作者 Xia YANG Zhi Wei MIAO Wei LIU Fang Ming MIAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第6期563-564,共2页
The Zinc complex of N, N-bis (benzimidazol 2-yl-methy])amine has been synthesized and its crystal structure determined by X-ray diffraction method. The structure features of the complex are described.
关键词 Zinc compex n n-bis (benzimidazol-2-yl-methyl)amine superoxide dismutase (SOD)
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Synthesis, Crystal Structure and Thermal Properties of N,N′-Bis(5,5-dimethyl-2-phospha-2-thio-1,3-dioxan-2-yl) Ethylene Diamine 被引量:2
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作者 任元林 程博闻 +3 位作者 张金树 臧洪俊 康卫民 丁长坤 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第1期70-74,共5页
The title compound N,N'-bis(5,5-dimethyl-2-phospha-2-thio-1,3-dioxan-2-yl) ethylene diamine (DPTDEDA, C12H26N2O4P2S2) was synthesized by the reaction of neopentyl glycol, phosphorus thio-chloride and 1,2-ethylene... The title compound N,N'-bis(5,5-dimethyl-2-phospha-2-thio-1,3-dioxan-2-yl) ethylene diamine (DPTDEDA, C12H26N2O4P2S2) was synthesized by the reaction of neopentyl glycol, phosphorus thio-chloride and 1,2-ethylenediamine, and characterized by elemental analysis, IR and ^1H NMR spectra. Its crystal structure was determined by single-crystal X-ray diffraction analysis and the thermal property was analyzed by TG analysis. The crystal structure belongs to monoclinic, space group P21/c, with a = 14.557(16), b = 11.299(12), c = 12.163(13)A,β = 98.707(19)^o, Dc = 1.305 g/cm^3, Z = 4, γ = 0.71073A,μ(MoKa) = 0.447 mm^-1, Mr = 388.41, V = 1977(4)A3, F(000) = 824, S = 1.107, the final R = 0.0478 and wR = 0.0810 for 1738 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that the crystal structure is centrosymmetrically distributed through 1,2-ethylenediamine to join two distorted six-membered rings. The weak N-H…S interactions are observed and link the molecules into sheets. TG analysis shows that the title compound has good thermal stability and char-forming capability, which are required for an excellent intumescent fire retardant. 展开更多
关键词 n n'-bis(5 5-dimethyl-2-phospha-2-thio-1 3-dioxan-2-yl) ethylene diamine phos-phorus thiochloride crystal structure thermal property intumescent fire retardant
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Synthesis and Crystal Structure of 3,3'-Bis(5-(N-(4-hydroxylphenyl)imidomethyl)- pyrrol-2-yl)pentane·2CH_3OH 被引量:3
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作者 徐兰 刘尚远 尹振明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第4期613-617,共5页
3,3'-Bis(5-(N-(4-hydroxylphenyl)imidomethyl)pyrrol-2-yl)pentane 1 has been synthesized and characterized. The crystal of its methanol complex, 1·(CH3OH)2, belongs to the orthorhombic system, space group ... 3,3'-Bis(5-(N-(4-hydroxylphenyl)imidomethyl)pyrrol-2-yl)pentane 1 has been synthesized and characterized. The crystal of its methanol complex, 1·(CH3OH)2, belongs to the orthorhombic system, space group Pccn with a = 18.094(2), b = 11.6890(16), c = 13.3629(19) , V = 2826.3(7) 3, Z = 8, C14.5H18N2O2, Mr = 252.31, Dc = 1.186 g/cm3, F(000) = 1080 and μ(MoKα) = 0.080 mm-1. The final R = 0.0662 and wR = 0.1801 for 1908 observed reflections with I 2σ(I), and R = 0.0800 and wR = 0.1948 for all reflections. In the solid state, bridged by included methanol molecules, the molecules of compound 1 form interpenetrated grid structure through N–H···O and O–H···O hydrogen bonds. 展开更多
关键词 3 3‘-bis(5-(n-(4-hydroxylphenyl)imidomethyl)pyrrol-2-yl)pentane crystal structure hydrogen bonding
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Synthesis and Crystal Structure of (1S)-1,1'-Bis{[N-ethyl-N-(1-methylethyl)-amino]-carbonyl}-2-(hydroxydiphenylmethyl)-ferrocene
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作者 YUAN Hao ZHOU Zhi-Ming XU Bao-Cai 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第7期827-830,共4页
The title complex,(1S)-1,1'-bis{[N-ethyl-N-(1-methylethyl)-amino]carbonyl}-2-(hydroxyldiphenylmethyl)-ferrocene([Fe(C_(24)H_(22)NO_(2))(C_(11)H_(16)NO)]_(2)·H_(2)O,Mr=1207.13),was synthesized via(-)-Sparteine... The title complex,(1S)-1,1'-bis{[N-ethyl-N-(1-methylethyl)-amino]carbonyl}-2-(hydroxyldiphenylmethyl)-ferrocene([Fe(C_(24)H_(22)NO_(2))(C_(11)H_(16)NO)]_(2)·H_(2)O,Mr=1207.13),was synthesized via(-)-Sparteine-mediated enantioselective directed ortho-lithiation of 1,1‘-bis{[N-ethyl-N-(1-methylethyl)-amino]carbonyl}-2-(hydroxydiphenylmethyl)-ferrocene.The structure of the rifle compound was determined by X-ray single-crystal diffraction.The crystal belongs to the orthorhombic system,space group P2_(1)2_(1)2_(1),with a=10.266(2),b=17.676(4),c=34.097(7)A,V=6187(2)A3,Z=4,C_(70)H_(86)Fe_(2)N_(4)O_(7),Dc=1.296 g/cm^(3),μ=0.527 mm^(-1),T=113(2)K,F(000)=2568,the final R=0.0469 and wR=0.0984 for 13940 observed reflections with I〉2σ(I).The neighboring ferrocene derivatives are joined into dimers via O-H…O=C intermolecular hydrogen bonding by a water molecule.Besides,the dimers form neat rows along the a axis. 展开更多
关键词 (1S)-1 1'-bis{[n-ethyl-n-(1-methylethyl)-amino]carbonyl}.2-(hydroxydiphenylmethyl)-ferrocene enantioselective synthesis crystal structure
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Novel indirect Z-scheme g-C3N4/Bi2MoO6/Bi hollow microsphere heterojunctions with SPR-promoted visible absorption and highly enhanced photocatalytic performance 被引量:8
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作者 Ning Li Hang Gao +7 位作者 Xin Wang Sujun Zhao Da Lv Guoqing Yang Xueyun Gao Haikuan Fan Yangqin Gao Lei Ge 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第3期426-434,共9页
The surface plasmonic resonance(SPR)effect of Bi can effectively improve the light absorption abilities and photogenerated charge carrier separation rate.In this study,a novel ternary heterojunction of g-C3N4/Bi2MoO6/... The surface plasmonic resonance(SPR)effect of Bi can effectively improve the light absorption abilities and photogenerated charge carrier separation rate.In this study,a novel ternary heterojunction of g-C3N4/Bi2MoO6/Bi(CN/BMO/Bi)hollow microsphere was successfully fabricated through solvothermal and in situ reduction methods.The results revealed that the optimal ternary 0.4 CN/BMO/9 Bi photocatalyst exhibited the highest photocatalytic efficiency toward rhodamine B(RhB)degradation with nine times that of pure BMO.The DRS and valence band of the X-ray photoelectron spectroscopy spectrum demonstrate that the band structure of 0.4 CN/BMO/9 Bi is a z-scheme structure.Quenching experiments also provided solid evidence that the·O^2-(at-0.33 eV)is the main species during dye degradation,and the conduction band of g-C3N4 is only the reaction site,demonstrating that the transfer of photogenerated charge carriers of g-C3N4/Bi2 MoO 6/Bi is through an indirect z-scheme structure.Thus,the enhanced photocatalytic performance was mainly ascribed to the synergetic effect of heterojunction structures between g-C3N4 and Bi2MoO6 and the SPR effect of Bi doping,resulting in better optical absorption ability and a lower combination rate of photogenerated charge carriers.The findings in this work provide insight into the synergism of heterostructures and the SPR absorption ability in wastewater treatment. 展开更多
关键词 g-C3n4/bi2MoO6/bi Z-scheme catalyst Surface plasmonic resonance effect Rhodamine B Visible light
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Bismuth-Based Free-Standing Electrodes for Ambient-Condition Ammonia Production in Neutral Media 被引量:3
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作者 Ying Sun Zizhao Deng +7 位作者 Xi‑Ming Song Hui Li Zihang Huang Qin Zhao Daming Feng Wei Zhang Zhaoqing Liu Tianyi Ma 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第10期164-175,共12页
Electrocatalytic nitrogen reduction reaction is a carbon-free and energy-saving strategy for efficient synthesis of ammonia under ambient conditions.Here,we report the synthesis of nanosized Bi2O3 particles grown on f... Electrocatalytic nitrogen reduction reaction is a carbon-free and energy-saving strategy for efficient synthesis of ammonia under ambient conditions.Here,we report the synthesis of nanosized Bi2O3 particles grown on functionalized exfoliated graphene(Bi2O3/FEG)via a facile electrochemical deposition method.The obtained free-standing Bi2O3/FEG achieves a high Faradaic efficiency of 11.2%and a large NH3 yield of 4.21±0.14μgNH3 h^-1 cm^-2 at-0.5 V versus reversible hydrogen electrode in 0.1 M Na2SO4,better than that in the strong acidic and basic media.Benefiting from its strong interaction of Bi 6p band with the N2p orbitals,binder-free characteristic,and facile electron transfer,Bi2O3/FEG achieves superior catalytic performance and excellent long-term stability as compared with most of the previous reported catalysts.This study is significant to design low-cost,high-efficient Bi-based electrocatalysts for electrochemical ammonia synthesis. 展开更多
关键词 n2 reduction bi2O3 nanoplate ELECTROCATALYSIS FREE-STAnDInG
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输运溶剂浮区法生长Bi_(2+x)Sr_(2-x)Ca_(n-1)Cu_nO_(2n+4+d)晶体
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作者 C.T.Lin(Max Planck Institute for Solid State Physics 70569 Stuttgart,Germany) 《人工晶体学报》 EI CAS CSCD 北大核心 2000年第S1期127-127,共1页
The growth of crystals of the high T c oxide superconductors has been hampe red by the complexities of the materials and their phase diagrams.The most common crys tal growth technique adopted for these oxides is the ... The growth of crystals of the high T c oxide superconductors has been hampe red by the complexities of the materials and their phase diagrams.The most common crys tal growth technique adopted for these oxides is the “flux”method,where the st arting materials are solved in a melt,which is usually formed by excess CuO and BaO or a KCl/NaCl mixture.The crystals are produced by slow cooling of the heate d solvent.This method,however,suffers from several disadvantages: (1) the crystals are contaminated with the crucible material, (2) the crystals are difficult to remove from the crucible, (3) the crystals contain flux inclusions. 展开更多
关键词 bi 2+ x Sr 2- x Ca n -1 Cu n O 2 n+4+d crystal travelling solvent floating zone method superconductor
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g-C_3N_4/Bi_2O_3复合型催化剂的制备及光催化性能研究 被引量:3
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作者 赵慧平 孙芳文 +2 位作者 吕中 田凡 陈嵘 《华中师范大学学报(自然科学版)》 CAS 北大核心 2015年第5期746-752,共7页
采用碾磨-焙烧法制备得到了g-C3N4/Bi2O3复合型催化剂.利用XRD、SEM、FT-IR、XPS、DRS及PL对所得样品进行了表征.以甲基橙溶液为模拟有机污染物,考察了g-C3N4/Bi2O3复合型催化剂的可见光催化性能.结果表明,复合结构的g-C3N4/Bi2O3催化... 采用碾磨-焙烧法制备得到了g-C3N4/Bi2O3复合型催化剂.利用XRD、SEM、FT-IR、XPS、DRS及PL对所得样品进行了表征.以甲基橙溶液为模拟有机污染物,考察了g-C3N4/Bi2O3复合型催化剂的可见光催化性能.结果表明,复合结构的g-C3N4/Bi2O3催化剂光谱响应范围拓宽至可见光区域,且g-C3N4/Bi2O3复合型催化剂的催化性能均明显优于单组分.其中,50 wt%g-C3N4/Bi2O3复合物对甲基橙可见光降解性能最佳.催化活性提升的主要原因是复合结构的形成有效促进了光生电子与空穴对的分离.此外,活性物种捕获实验结果表明,光生空穴(h+)及超氧自由基(·O-2)为该光催化反应过程中的主要活性物种. 展开更多
关键词 g-C3n4 bi2O3 复合型催化剂 可见光 催化性能
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g-C3N4量子点修饰球形Bi2WO6及其光催化活性增强机制 被引量:4
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作者 郭莉 张开来 +5 位作者 张鑫 赵芳丽 赵强 杨晓 王丹军 付峰 《材料工程》 EI CAS CSCD 北大核心 2019年第11期128-134,共7页
采用水热法制备三维分级结构Bi2WO6,在此基础上采用浸渍-焙烧法将g-C3N4量子点成功沉积在Bi2WO6的表面,获得Z-型结构g-C3N4/Bi2WO6光催化剂。采用XRD,FE-SEM,TEM,UV-Vis-DRS测试手段对催化材料的组成、形貌和光吸收特性进行表征。以亚... 采用水热法制备三维分级结构Bi2WO6,在此基础上采用浸渍-焙烧法将g-C3N4量子点成功沉积在Bi2WO6的表面,获得Z-型结构g-C3N4/Bi2WO6光催化剂。采用XRD,FE-SEM,TEM,UV-Vis-DRS测试手段对催化材料的组成、形貌和光吸收特性进行表征。以亚甲基蓝(MB)和对硝基苯酚(p-NPh)为模型污染物,考察g-C3N4量子点表面修饰对Bi2WO6光催化活性的影响。结果表明:所得Bi2WO6为三维分级多孔结构,孔尺寸约为10nm,浸渍-焙烧法可将尺寸约5nm的g-C3N4量子点沉积在其二级结构纳米片表面。Z-型结构g-C3N4/Bi2WO6光催化剂的催化活性优于纯Bi2WO6的,且10%g-C3N4/Bi2WO6(质量分数)异质光催化剂对MB的降解表观速率常数(kapp)分别为纯Bi2WO6和g-C3N4的4.5倍和5.8倍,对p-NPh的kapp分别为纯Bi2WO6和g-C3N4的2.6倍和1.6倍。O2·是光催化过程中的主要活性物种。g-C3N4量子点与Bi2WO6形成异质结,有利于拓宽光响应范围的同时有效抑制了Bi2WO6光生电子与空穴的复合,从而提高了催化剂的活性。 展开更多
关键词 三维bi2WO6 量子点修饰 Z-型g-C3n4/bi2WO6 活性增强机理
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Bi2O3/g-C3N4/TiO2三元复合物的制备及其可见光催化活性研究 被引量:5
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作者 徐海燕 傅敏 王瑞琪 《人工晶体学报》 EI CAS CSCD 北大核心 2015年第9期2524-2531,共8页
以工业纳米Ti O2,三聚氰胺(C3H6N6)和硝酸铋(Bi(NO3)3·5H2O)为原料,通过高温煅烧制备Bi2O3/gC3N4/Ti O2三元复合物,采用XRD、XPS、FT-IR、UV-vis、PL光谱等对其结构进行了表征。结果表明g-C3N4和Bi2O3分散覆盖在Ti O2表面,形成具... 以工业纳米Ti O2,三聚氰胺(C3H6N6)和硝酸铋(Bi(NO3)3·5H2O)为原料,通过高温煅烧制备Bi2O3/gC3N4/Ti O2三元复合物,采用XRD、XPS、FT-IR、UV-vis、PL光谱等对其结构进行了表征。结果表明g-C3N4和Bi2O3分散覆盖在Ti O2表面,形成具有异质结结构的Bi2O3/g-C3N4/Ti O2三元复合物,其带隙降低,对可见光的吸收增强,电子和空穴通过在Bi2O3、g-C3N4和Ti O2三者界面间的转移有效延长了光生载流子的寿命,从而提高光催化效率。以亚甲基蓝为目标污染物评价其光催化活性。结果表明,当Ti O2与C3H6N6质量比为1∶2.5,Bi(NO3)3·5H2O含量为0.35%,煅烧温度为520℃,煅烧时间为5 h时制得的Bi2O3/g-C3N4/Ti O2三元复合物(即0.35Bi/C/T)活性最高,LED灯(12 W)光照180 min后对10mg/L亚甲基蓝溶液降解率达98.1%。 展开更多
关键词 bi2O3/g-C3n4/TiO2三元复合物 亚甲基蓝 光催化
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Bi_2O_3/g-C_3N_4复合催化剂的制备及其性能研究 被引量:7
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作者 张文保 崔玉民 +3 位作者 李慧泉 苗慧 陶栋梁 孙倩 《阜阳师范学院学报(自然科学版)》 2015年第1期29-34,共6页
分别以硫脲、尿素、二氰二胺为前驱体,采用热解法合成g-C3N4,再将其与Bi2O3以不同质量比复合煅烧制备Bi2O3/g-C3N4光催化剂,并用XRD、紫外-可见光谱、光致发光光谱等对其进行了表征。以甲基橙为光催化反应的模型化合物,评价了Bi2O3/g-C... 分别以硫脲、尿素、二氰二胺为前驱体,采用热解法合成g-C3N4,再将其与Bi2O3以不同质量比复合煅烧制备Bi2O3/g-C3N4光催化剂,并用XRD、紫外-可见光谱、光致发光光谱等对其进行了表征。以甲基橙为光催化反应的模型化合物,评价了Bi2O3/g-C3N4光催化剂的紫外光催化活性。探索添加不同清除剂(异丙醇、草酸铵、对苯醌、H2O2酶)后对紫外光催化活性的影响;以对苯二甲酸作为探针分子,结合化学荧光技术研究了Bi2O3/g-C3N4光催化剂表面羟基自由基的生成。实验结果表明:(1)在450℃下煅烧硫脲制备的g-C3N4具有较高的光催化活性;(2)当g-C3N4在Bi2O3/g-C3N4复合光催化剂中质量百分率为80%时,Bi2O3/g-C3N4的光催化活性最高,甲基橙的光催化降解率达到59.1%。 展开更多
关键词 g-C3n4 bi2O3 光催化 清除剂 甲基橙
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热塑形方法制备N型Bi_2Te_3材料(英文)
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作者 张丽丽 张建中 +1 位作者 侯旭峰 任保国 《材料科学与工程学报》 CAS CSCD 北大核心 2007年第6期954-957,共4页
本文介绍了采用热塑形方法制备N型Bi2Te3温差电材料。并且给出了所获得样品的密度、抗弯强度、SEM以及温差电性能(包括电导率和塞贝克系数)的测试结果。实验结果表明,在最佳的热塑形工艺下制备的样品的功率因子与区熔材料相当,但其机械... 本文介绍了采用热塑形方法制备N型Bi2Te3温差电材料。并且给出了所获得样品的密度、抗弯强度、SEM以及温差电性能(包括电导率和塞贝克系数)的测试结果。实验结果表明,在最佳的热塑形工艺下制备的样品的功率因子与区熔材料相当,但其机械强度要明显优于区熔材料。热压塑形样品在垂直于塑形压力的方向上具有良好的取向,并且样品在此方向上的功率因子远远大于其在平行压力方向上的功率因子值。 展开更多
关键词 nbi2Te3材料 热塑形 取向 温差电性能
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新型光稳定剂N,N'-二甲酰-N,N'-二(2,2,6,6-四甲基-4-哌啶)-己二胺的合成研究 被引量:1
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作者 李世昌 苑丽红 +3 位作者 敖晓娟 谭卓华 王庆 杨育农 《合成材料老化与应用》 2015年第6期20-22,共3页
光稳定剂N,N'-二甲酰-N,N'-二(2,2,6,6-四甲基-4-哌啶)-己二胺具有优异的性能,我们以N,N'-二(2,2,6,6-四甲基-4-哌啶基)-1,6-己二胺为原料,以甲酰胺为酰化剂,在酸催化剂介导下得到目标产品,着重考察了催化剂对反应的影响。
关键词 光稳定剂 n n'-二甲酰-n n'-二(2 2 6 6-四甲基-4-哌啶)-己二胺
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零维/二维Bi2S3/g-C3N4异质结的原位构建及光催化性能 被引量:3
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作者 李玉佩 王晓静 +3 位作者 赵君 胡秋月 王利勇 成永强 《材料导报》 EI CAS CSCD 北大核心 2020年第15期15033-15038,共6页
采用简单的一步溶剂热法,以硝酸铋为铋源,硫代硫酸钠为硫源,将Bi2S3纳米粒子原位修饰在g-C3N4纳米片上,成功制备了零维/二维Bi2S3/g-C3N4异质结。利用XRD、SEM、TEM、UV-Vis、荧光光谱以及电化学分析方法等手段对所制备的光催化材料进... 采用简单的一步溶剂热法,以硝酸铋为铋源,硫代硫酸钠为硫源,将Bi2S3纳米粒子原位修饰在g-C3N4纳米片上,成功制备了零维/二维Bi2S3/g-C3N4异质结。利用XRD、SEM、TEM、UV-Vis、荧光光谱以及电化学分析方法等手段对所制备的光催化材料进行了表征。在可见光照射下,以罗丹明B(RhB)为模型污染物,研究其光催化降解效率。结果表明,Bi2S3以纳米颗粒的形式分散于g-C3N4纳米片上,形成了零维/二维异质结结构,拓宽了g-C3N4在可见光区的吸收,降低了电子-空穴对的复合概率;与纯g-C3N4相比,Bi2S3/g-C3N4异质结表现出更高的光催化效率。同时,Bi2S3/g-C3N4催化剂具有良好的光催化稳定性,经过5次循环后其光催化活性基本稳定。 展开更多
关键词 bi2S3/g-C3n4 异质结 罗丹明B 光催化性能
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