期刊文献+
共找到16篇文章
< 1 >
每页显示 20 50 100
X-ray Spectroscopically Probing Mo_(2)C@MoSe_(2)Heterojunction Electrodes
1
作者 CAO Yu-yang WEI Shi-qiang +5 位作者 JIANG Wei Peter Joseph Chimtali YAN Zi-wei ZHOU Quan CHEN Shuang-ming SONG Li 《分析测试学报》 CAS CSCD 北大核心 2024年第10期1618-1625,共8页
Due to their high electrical conductivity and layered structure,two dimensional MXene materials are re⁃garded as promising candidates for energy storage applications.However,the relatively low stability and specific c... Due to their high electrical conductivity and layered structure,two dimensional MXene materials are re⁃garded as promising candidates for energy storage applications.However,the relatively low stability and specific ca⁃pacity of MXene materials limit their further utilization.In this study,these issues are addressed using a heterostruc⁃ture strategy via a one-step selenization method to form Mo_(2)C@MoSe_(2).Synchrotron radiation X-ray spectroscopic and high-resolution transmission electron microscopy(HRTEM)characterizations revealed the heterostructure consisting of in-situ grown MoSe_(2)on Mo_(2)C MXene.Electrochemical tests proved the heterojunction electrode’s superior rate perfor⁃mance of 289.06 mAh·g^(-1)at a high current density of 5 A·g^(-1)and long cycling stability of 550 mAh·g^(-1)after 900 cycles at 1 A·g^(-1).This work highlights the useful X-ray spectroscopic analysis to directly elucidate the heterojunction structure,providing an effective reference method for probing heterostructures. 展开更多
关键词 X-ray spectroscopic MXene HETEROJUNCTION X-ray absorption fine structure lithium-ion batteries
在线阅读 下载PDF
Preparation and Spectroscopic of Vanadyl(Ⅱ) Vitamin D3 Amino Acid Mixed Complexes as Insulin Mimetic Drug
2
作者 Enas Aljuhani Amnah M.A.Alsuhaibani +3 位作者 A.M.El-Di damony N.Hassan Sameh Abo Taleb Moamen S.Refat 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2019年第7期2316-2324,共9页
A new six intraperitoneal injection insulin-mimetic vanadyl(Ⅱ) compounds [(VD3^-1)(VO^+2)(AAn^-1)](where(n=1~6);AA1=isoleucine, AA2=threonine, AA3=proline, AA4=phenylalanine, AA5=lysine and AA6=glutamine) were synthe... A new six intraperitoneal injection insulin-mimetic vanadyl(Ⅱ) compounds [(VD3^-1)(VO^+2)(AAn^-1)](where(n=1~6);AA1=isoleucine, AA2=threonine, AA3=proline, AA4=phenylalanine, AA5=lysine and AA6=glutamine) were synthesized by the chemical reactions between vitamin D3(VD3), VOSO4 and amino acids(AAn) with equal molar ratio 1∶1∶1 in neutralized media. The structures of these complexes were elucidated by spectroscopic methods like, infrared and solid reflectance spectroscopes. Magnetic moments and electronic spectra reveal square pyramid geometrical structure of the complexes. The infrared spectra assignments of these complexes revealed that the chelation towards vanadyl(Ⅳ) ions existed via deprotonation of the hydroxyl group of VD3 drug ligand and so amino acids act as bidentate ligand via N-amino and O-carboxylate groups. The anti-diabetic efficiency of these complexes were evaluated against streptozotocin induced diabetic male albino rats. 展开更多
关键词 INSULIN alternative Diabetes DRUG VO^2+ ion VITAMIN D3 Amino acid spectroscopic
在线阅读 下载PDF
Synthesis, Spectroscopic and Antimicrobial Investigations of Scandium(Ⅲ) Complexes with Four Kinds of Sulfa Drugs
3
作者 Moamen S.Refat Abeer A.El-Habeeb 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2020年第3期985-990,共6页
Herein,this article was focused on the synthesis and discussed the spectroscopic characterizations of four new scandium(Ⅲ)sulfa-drug complexes.The nomenclature and symbols of these drugs were sulfadimidine(sulp-1),su... Herein,this article was focused on the synthesis and discussed the spectroscopic characterizations of four new scandium(Ⅲ)sulfa-drug complexes.The nomenclature and symbols of these drugs were sulfadimidine(sulp-1),sulfanilamide(sulp-2),sulfamethoxazole(sulp-3)and sulfadiazine(sulp-4).The microanalytical and spectroscopic analyses which utilized in this study were micro-analyses,magnetic,FT-IR,UV-Vis techniques.The mid infrared spectra deduced that the four sulfa-drug chelates acts as a bidentate chelates with scandium(Ⅲ)ion via two nitrogen atoms of-NH2-Ar and-NH-SO2 groups.Also,the FTIR spectra of Sc3+complexes referred to the existed of new medium weak bands in the range of 500~400 cm^-1 due to stretching vibration bands ofν(M-N).The elemental analysis technique confirmed the 1∶2 stoichiometry between Sc3+ions and sulp ligand with molecular formula[Sc(sulp)2(Cl)2]·Cl.At room temperature,the results of magnetic measurements for the Sc(Ⅲ)complexes indicated that all of the synthesized complexes have a diamagnetic character with octahedral configuration.The electronic spectra of the free sulfa-drug ligands shows band at 275 and 310 nm which are intraligand charge transfer band.The electronic sbsorption spectra of the Sc3+complexes were recorded using DMSO solvent.The spectra of complexes display bands within 275~388 nm,which attributed toπ-π*,n-π*and charge-transfer M-LCT electronic transitions,which strongly favors the octahedral geometry around Sc(Ⅲ)metal ions.1HNMR spectra of complexes referred to the downfield proton shifts of the-NH2 and NHSO2 groups,which supported the place of coordination.The half maximal inhibitory concentration(IC50)of the ScⅢcomplexes was assessed against the human hepato cellular carcinoma(HepG-2)tumor cell line. 展开更多
关键词 Sulfa-drugs Sc~Ⅲ spectroscopic CHELATION NANO-PARTICLES ANTIMICROBIAL
在线阅读 下载PDF
Spectroscopic and Fluorescence Studies on the Trivalent Ce,Eu,Nd and La Metal Ions Rhodamine CFlorescent Dye Complexes
4
作者 Moamen S.Refat Mahmoud Salman +3 位作者 Akram M.El-Didamony Hammad Fetooh Eman S.E.Abd El-Maksoud Mohamed Y.El-Sayed 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2021年第10期3311-3315,共5页
The four isolates solid complexes:[La(RHC)(NO_(3))_(2)]·3H_(2)O,[Nd(RHC)(NO_(3))_(2)]·4H_(2)O,[Eu(RHC)(NO_(3))_(2)]·2H_(2)O,and[Ce(RHC)(NO_(3))_(2)]·5H_(2)O that obtained by the reaction of the nit... The four isolates solid complexes:[La(RHC)(NO_(3))_(2)]·3H_(2)O,[Nd(RHC)(NO_(3))_(2)]·4H_(2)O,[Eu(RHC)(NO_(3))_(2)]·2H_(2)O,and[Ce(RHC)(NO_(3))_(2)]·5H_(2)O that obtained by the reaction of the nitrate salts of the Ce(Ⅲ),Eu(Ⅲ),Nd(Ⅲ)and La(Ⅲ)ions and rhodamie C(RHC)ligand were interpretative using elemental analysis(C,H and N),molar conductivity,infrared,electronic,fluorescence and 1H-NMR spectra to achieve the speculated suitable formula.The low molar conductance values of the synthesized RHC complexes concluded the non-electrolytic behavior.The infrared spectra recorded the absence of stretching vibrationν(OH)of the—COOH and presence of two new vibration bands at 1597~1601 and 1383~1399 cm^(-1)which were assigned toνas(COO-)andνs(COO-).The difference between them revealed that the carboxylate group acts as a bidentate ligand.1HNMR spectra of Europium and lanthanum(Ⅲ)complexes were supported the FTIR results based on the absent of proton of the carboxylic group.Therefore,the microanalytical and spectroscopic results deduced that RHC acts as a monobasic bidentate ligand,and coordinated to the central metal(Ⅲ)ions via the two oxygen atoms of deprotonated carboxylic group.Fluorescence studies were performed on the metal complexes of Ce^(3+),Tb^(3+),Th^(4+),Gd^(3+)and La^(3+),that referred a quenching in the fluorescene intensity of rhodamine C in the aqueous state after complexation.The antimicrobial assessment against some kind of bacteria and fungi were also checked and recorded enhancement in case of their complexes. 展开更多
关键词 Rhodamine C CHELATION spectroscopic THERMOGRAVIMETRIC LANTHANIDES
在线阅读 下载PDF
SPECTROSCOPIC DATA FOR HIGHLY CHARGED IONS
5
作者 Shichang Li Yongsheng SunGuoxing Han and Hanyang YangInstitute of Applied Physics and Computational MathematicsYonglu Yang and Lixian ChenChinese Research Association for Atomic and Molecular Data (P.O. Box 8009, Beijing, China) 《原子与分子物理学报》 CAS CSCD 北大核心 1990年第S1期175-176,共2页
The purpose of the present work is to provide the immense amount ofatomic data needed for applications to the ICF and X—ray laser research workin our institute and for the compilation—evaluation work in Chinese Rese... The purpose of the present work is to provide the immense amount ofatomic data needed for applications to the ICF and X—ray laser research workin our institute and for the compilation—evaluation work in Chinese ResearchAssociation for Atomic and Molecular Data. Using the non—relativistic Hartree—Fock self—consistent field method in-cluding the relativistic mass—velocity and Darwin terms in theHamiltonian(HFR) proposed by Dr.R.Cowan we have calculated 展开更多
关键词 RELATIVISTIC HARTREE IMMENSE Atomic institute DARWIN spectroscopic Nuclear decay RADIATIVE
在线阅读 下载PDF
Spectroscopic Features and Coloration of Gem-Quality Green Tsavorite in Major International Deposits and China
6
作者 L Linsu ZHANG Yong +3 位作者 LI Hongbo LU Taijin MAO Bing CHEN Hua 《矿物学报》 CAS CSCD 北大核心 2013年第S1期63-63,共1页
Tsavorite green colored by Cr3+/V3+ has been traditionally found and mined in Tanzania, Kenya and Madagascar in the Neoproterozoic Mozambique metamorphic belt (NMMB), and recently be found in Sanjiang, Litang, Sichuan... Tsavorite green colored by Cr3+/V3+ has been traditionally found and mined in Tanzania, Kenya and Madagascar in the Neoproterozoic Mozambique metamorphic belt (NMMB), and recently be found in Sanjiang, Litang, Sichuan, China. The differences of the chemical formula, spectroscopic features, as well as the concentrations of the V2O3 and Cr2O3 in the tsavorite crystals collected from major international deposits and Sanjiang, China have been investigated using EPMA, XRF, UV-VIS spectrometers, FTIR, Raman scattering microscopy, DiamondView TM techniques. It was found that the chemical formulas of African tsavorite and Chinese tsavorite are Ca3(Al,V)2[SiO4]3 and Ca3(Al,Cr)2[SiO4]3, respectively, indicating that tsavorite is a solid solution between dominant grossular and minor goldmanite and uvarovite. Two broad bands centered at 430 nm and 605 nm were the main absorption features in the tsavorite samples, which attribute to the absorption of Cr3+ and/or V3+ ions in the lattice. The green coloration is caused by Cr3+ and/or V3+ ions resulting in the absorption of purple and red components of the visible light. Absorptions caused of Fe3+ and Fe2+ ions could add the bluish color component in some of tsavorite samples. The intensity of green color is proportional to the concentrations of V2O3 and Cr2O3. The basic gemological properties, such as refractive index in the investigated samples were presented, and the definition and chemical and spectroscopic properties of tsavorite are discussed. 展开更多
关键词 tsavorite spectroscopic feature COLORATION China EAST AFRICA
在线阅读 下载PDF
High-brightness and Monodisperse Quaternary CuInZnS@ZnS Quantum Dots with Tunable and Long-lived Emission
7
作者 CHEN Zi ZHANG Aidi +5 位作者 GONG Ke LIU Haihua YU Gang SHAN Qingsong LIU Yong ZENG Haibo 《无机材料学报》 北大核心 2025年第4期433-439,I0017-I0021,共12页
As an essential candidate for environment-friendly luminescent quantum dots(QDs),CuInS-based QDs have attracted more attention in recent years.However,several drawbacks still hamper their industrial applications,such ... As an essential candidate for environment-friendly luminescent quantum dots(QDs),CuInS-based QDs have attracted more attention in recent years.However,several drawbacks still hamper their industrial applications,such as lower photoluminescence quantum yield(PLQY),complex synthetic pathways,uncontrollable emission spectra,and insufficient photostability.In this study,CuInZnS@ZnS core/shell QDs was prepared via a one-pot/three-step synthetic scheme with accurate and tunable control of PL spectra.Then their ensemble spectroscopic properties during nucleation formation,alloying,and ZnS shell growth processes were systematically investigated.PL peaks of these QDs can be precisely manipulated from 530 to 850 nm by controlling the stoichiometric ratio of Cu/In,Zn^(2+)doping and ZnS shell growth.In particular,CuInZnS@ZnS QDs possess a significantly long emission lifetime(up to 750 ns),high PLQY(up to 85%),and excellent crystallinity.Their spectroscopic evolution is well validated by Cu-deficient related intragap emission model.By controlling the stoichiometric ratio of Cu/In,two distinct Cu-deficient related emission pathways are established based on the differing oxidation states of Cu defects.Therefore,this work provides deeper insights for fabricating high luminescent ternary or quaternary-alloyed QDs. 展开更多
关键词 quantum dot CuInS ALLOYING core/shell ensemble spectroscopic Cu-deficient related emission
在线阅读 下载PDF
高温高压下NaCl-H_2O体系的Raman光谱分析:一种新的流体包裹体盐度测定方法 被引量:2
8
作者 杨玉萍 郑海飞 +2 位作者 张立飞 刘曦 邓松涛 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第8期2023-2028,共6页
利用水热金刚石压腔研究了高温高压下0.0%、5.0%、10.0%和20.0%的NaCl-H_2O体系的Raman光谱,研究结果发现:对于盐度一定的NaCl-H_2O体系,当压力不变时,水的Raman伸缩谱峰的波数变化量△v_((O-H))随温度的升高而不断增加;当压力不同时,△... 利用水热金刚石压腔研究了高温高压下0.0%、5.0%、10.0%和20.0%的NaCl-H_2O体系的Raman光谱,研究结果发现:对于盐度一定的NaCl-H_2O体系,当压力不变时,水的Raman伸缩谱峰的波数变化量△v_((O-H))随温度的升高而不断增加;当压力不同时,△v_((O-H))随温度的变化关系(偏移斜率S)不受压力的影响,而只与盐度相关。利用该性质可以用来确定流体包襄体的盐度(W),其计算公式如下:W=123.25S^2-128.11S+32.40,误差为0.46%。 展开更多
关键词 高温高压 体系 RAMAN光谱 分析 流体包裹体 盐度 测定方法 HIGH temperature HIGH pressure spectroscopic analysis fluid inclusion SALINITY method of STRETCHING vibration different determination of frequency shift 压力 relationship application
在线阅读 下载PDF
The relationship between IR characteristic peak and microstructure of the glass used as optical fiber 被引量:4
9
作者 段吉安 蔡国华 帅词俊 《Journal of Central South University of Technology》 2006年第3期238-241,共4页
Based on the harmonic vibration equation, the relationship between IR characteristic peak of fiberglass and Si-O-Si bond angle was deduced, and 1 100 cm^-1 characteristic peak was specifically studied. It is found tha... Based on the harmonic vibration equation, the relationship between IR characteristic peak of fiberglass and Si-O-Si bond angle was deduced, and 1 100 cm^-1 characteristic peak was specifically studied. It is found that 1 100 cm^-1 characteristic peak shifts to higher wave number when Si-O-Si bond angle increases. Taking fused biconical taper (FBT) coupler as an example, the microstructures of the fiber coupler manufactured at different draw- ing speeds were tested with micro infrared spectrum. According to the test results, it is found that the bond angle at the taper region is the largest, the one at the fused region is the second largest, and the one of bare fiber is the smal- lest. The characteristic peaks of fused-taper region shift to higher wave number when drawing speed increases. 展开更多
关键词 FIBERGLASS IR spectroscopic MICROSTRUCTURE
在线阅读 下载PDF
Fabrication of Semiconductor Polymer Membranes Combined with a Colored Charge Transfer Complexes Used in the Manufacture of Solar Cells as a Source of Alternative Energy
10
作者 Ahmed. I. El-Shenawy Ishaq. F. E. Ahmed Moamen. S. Refat 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2019年第7期2307-2315,共9页
The main task of this article was to prepared of new pigment model in situ solar cells accordance to charge-transfer complexes of rhodamine C(RhC) donor as dye laser gain media with iodine(σ-acceptor) and chloranilic... The main task of this article was to prepared of new pigment model in situ solar cells accordance to charge-transfer complexes of rhodamine C(RhC) donor as dye laser gain media with iodine(σ-acceptor) and chloranilic acid, CLA(π-acceptor). The synthesis stoichiometry of these complexes were of 1∶2(donor∶acceptor) with general formulas [(RhC)]I·I3 and [(RhC)(CLA)2]. The discussed data of elemental analysis, conductivity measurements, FT-IR, UV-Vis spectroscopy and photometric titration data visualized the stoichiometry, formula and complexity of the complexes. The physicochemical and spectroscopic analyses obtained suggested that the electron transfer occurred through nitrogen atom in a tertiary amine —N(C2H5)2 of RhC donor with acceptor. The synthesized solid complexes were under go to thermogravimetric analyses to investigate their thermal stability and decomposition steps. The molar conductance measurements revealed that RhC complexes have an electrolytic statement. The thermal stability of rhodamine C complexes was enhanced in comparable with RhC itself. The polymer membranes of poly-methyl methacrylate)(PMMA) combined with the RhC charge(transfer complexes in chloroform solvent have been prepared and characterized by(infrared & electronic) spectroscopy and scanning electron microscopy(SEM) morphological examination. The photo-stability properties of the RhC complexes have been investigated. 展开更多
关键词 CHARGE-TRANSFER RHODAMINE C PHOTOSTABILITY Complexity spectroscopic Polymer DYE
在线阅读 下载PDF
DNA Binding and Antitumor Activity of a New Fluores cent ProbeEu(Ⅲ)-Complex Containing 4-Methyl-Coumarin Moiety
11
作者 Belal H M Hussein Mostafa A Gouda +6 位作者 Omer Sakin Abdulla Faluji Mohamed Gomaa Hassan A Azab Walid Fathalla Sherin Arabi Sa wsan Mosa 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2018年第11期3611-3621,共11页
A new europium(Ⅲ)complex containing(4-Methyl-2-oxo-2 H-chromen-7-yloxy)-acetic acid moiety(CMMC)was synthesized,characterized,and confirmed as antitumor agent and fluorescent probe.The spectroscopic measurements of ... A new europium(Ⅲ)complex containing(4-Methyl-2-oxo-2 H-chromen-7-yloxy)-acetic acid moiety(CMMC)was synthesized,characterized,and confirmed as antitumor agent and fluorescent probe.The spectroscopic measurements of Eu(Ⅲ)in the presence of CMMC were obtained in different solvents.The results show that the strongest Eu(Ⅲ)emission bands were monitored in iso-propyl alcohol while the weakest Eu(Ⅲ)emission band was observed in acetonitrile.The interaction of Eu(Ⅲ)-(CMMC)2 complex with DNA was monitored using absorption and emission techniques.From fluorescence titration measurements,the binding constants of DNA with Eu(Ⅲ)-(CMMC)_2 complex were found to be 1.04×10~5 L·mol^(-1) in Tris-HCl and 1.17×10~7 L·mol^(-1) in DMSO-Tris-HCl buffer(9∶1 V/V).Hypochromism was observed from the absorption titration experiment which indicates the intercalation of Eu(Ⅲ)-complex between the base pair of DNA.This result further confirmed by fluorescent Ethidium bromide displacement assay.The fluorescence calibration curve was used for the determination of DNA with LOD of 1.2 ng in DMSO-Tris-HCl buffer(9∶1 V/V)and 5 ng in Tris-HCl buffer.The preliminary antitumor investigation shows promising cytotoxicity against MDA-MB-231,MCF-7(mammary cancer),and PC-3(prostate carcinoma)cell lines with IC50 values of 40.63,25.42 and 30.25μmol·L^(-1),respectively. 展开更多
关键词 EUROPIUM (4-Methyl-2-oxo-2H-chromen-7-yloxy)-acetic acid DNA sensing spectroscopic properties Antitumor activ ity
在线阅读 下载PDF
中华人民共和国国家标准(GB/T 7714—2015)参考文献著录格式示例摘录
12
《国际口腔医学杂志》 CAS 北大核心 2016年第2期142-142,共1页
1.普通图书[1]张伯伟.全唐五代诗格会考[M].南京:江苏古籍出版社,2002:288.2.论文集、会议录[1]雷光春.综合湿地管理:综合湿地管理国际研讨会论文集[C].北京:海洋出版社,2012.3.报告[1]World Health Organization.Factors regulatin... 1.普通图书[1]张伯伟.全唐五代诗格会考[M].南京:江苏古籍出版社,2002:288.2.论文集、会议录[1]雷光春.综合湿地管理:综合湿地管理国际研讨会论文集[C].北京:海洋出版社,2012.3.报告[1]World Health Organization.Factors regulating the immune response:report of WHO Scientific Group[R].Geneva:WHO,1970.4.学位论文[1]Calms RB.Infrared spectroscopic studies on solid oxygen[D].Berkeley:University of California,1965. 展开更多
关键词 湿地管理 研讨会论文集 著录格式 Infrared GB/T 7714 BERKELEY 诗格 会议录 Geneva spectroscopic
在线阅读 下载PDF
RESEARCH HOT FRONTS FOR NATURAL PRODUCT
13
《天然产物研究与开发》 CAS CSCD 2004年第3期224-224,共1页
关键词 FABER spectroscopic CAROTENE NORMALIZATION BASEL
在线阅读 下载PDF
Microstructure and microwave dielectric properties of lead borosilicate glass ceramics with Al_2O_3 被引量:4
14
作者 韦鹏飞 周洪庆 +2 位作者 王杰 张一源 曾凤 《Journal of Central South University》 SCIE EI CAS 2011年第6期1838-1843,共6页
The effects of Al2O3 addition on both the sintering behavior and microwave dielectric properties of PbO-B203-SiO2 glass ceramics were investigated by Fourier transform infrared spectroscope (FTIR), differential ther... The effects of Al2O3 addition on both the sintering behavior and microwave dielectric properties of PbO-B203-SiO2 glass ceramics were investigated by Fourier transform infrared spectroscope (FTIR), differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that with the increase of Al2O3 content the bands assigned to [SiO4] nearly disappear. Aluminum replaces silicon in the glass network, which is helpful for the formation of boron-oxygen rings. The increase of the transition temperature Tg and softening temperature Tf of PbO-B2O3-SiO2 glass ceramics leads to the increase of liquid phase precipitation temperature and promotes the structure stability in the glasses, and consequently contributes to the decreasing trend of crystallization. Densification and dielectric constants increase with the increase of Al2O3 content, but the dielectric loss is worsened. By contrast, the 3% (mass fraction) Al2O3-doped glass ceramics sintered at 725℃ have better properties of density p=2.72 g/cm3, dielectric constant Er=6.78, dielectric loss tan8=2.6×10^-3 (measured at 9.8 GHz), which suggest that the glass ceramics can be applied in multilayer microwave devices requiring low sintering temperatures. 展开更多
关键词 PbO-B203-SiO2 glass ceramics AL2O3 Fourier transform infrared spectroscope MICROSTRUCTURE dielectric properties
在线阅读 下载PDF
THE CATALYSIS OF IRON-COBALT BIMETALLIC CLUSTERS——1.THERMAL STABILITY AND DECOMPOSITION REACTION OF[R_4N][FeCo_3(CO)_(12)]IN SOLUTION
15
作者 Xue Shunqing, Wu Guangsun, Luo Yuzhong, FuHongxiang,Yang Xiaohe, Liu Shengming (Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, China) 《分子催化》 EI CAS CSCD 1989年第S1期8-14,共7页
Thermal decomposition of[R<sub>4</sub>N][FeCo<sub>3</sub>(CO)<sub>12</sub>][I](R=ethyl,butyl,hexadecyl,benzyltrimethyl,benzyltriethyl)in n-heptane,toluene and methanol was inves... Thermal decomposition of[R<sub>4</sub>N][FeCo<sub>3</sub>(CO)<sub>12</sub>][I](R=ethyl,butyl,hexadecyl,benzyltrimethyl,benzyltriethyl)in n-heptane,toluene and methanol was investigated bythe in situ high pressure IR spectroscopic method.The results show that underhydroformylation conditions all clusters decompose to Co<sub>2</sub>(CO)<sub>8</sub>,Fe(CO)<sub>5</sub> and the salt ofCo(CO)<sub>4</sub><sup>-</sup>,and Co<sub>2</sub>(CO)<sub>8</sub> reacts with H<sub>2</sub> to form HCo(CO)<sub>4</sub>.Thermal stability of theclusters decrease with the increase of polarity of solvents.Under the hydroformylation con-ditions,IR spectra of the clusters are compatible with those of Fe(CO)<sub>5</sub>+Co<sub>2</sub>(CO)<sub>8</sub>+[R<sub>4</sub>N]Cl system.Because of the stabilizing effect or tetra-alkylammonium cation,when the tem-perature drops below 50℃ after decomposition of the clusters,the characteristic absorptionbands of the clusters appear again,so the decomposition process is reversible. 展开更多
关键词 FECO CO IN SOLUTION compatible TETRA decompose REVERSIBLE polarity heating spectroscopic
原文传递
HYDROFORMYLATION OF ETHYLENE CATALYZED BY HOMOGENEOUS METAL CLUSTERS
16
作者 Fu Hongxiang, Luo Yuzong , Zhang Shuwei, Ren Xu (Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, China) 《分子催化》 EI CAS CSCD 1989年第S1期88-93,共6页
This paper deals with a study of hydroformylation of ethylene catalyzed by homoge-neous metal clusters.〔PhCH<sub>2</sub>Me<sub>3</sub>N〕〔FeCo<sub>3</sub>(CO)<sub>12</s... This paper deals with a study of hydroformylation of ethylene catalyzed by homoge-neous metal clusters.〔PhCH<sub>2</sub>Me<sub>3</sub>N〕〔FeCo<sub>3</sub>(CO)<sub>12</sub>〕and〔PhCH<sub>2</sub>Me<sub>3</sub>N〕〔RuCO<sub>3</sub>(CO)<sub>12</sub>〕show high catalytic activity for the hydroform ylation of ethylene compared with YCCo<sub>3</sub>(CO)<sub>9</sub>,CO<sub>4</sub>(CO)<sub>10</sub>(PPh)<sub>2</sub>,Co<sub>2</sub>(CO)<sub>6</sub>(PBu<sub>3</sub>)<sub>2</sub>,and Fe<sub>2</sub>(CO)<sub>4</sub>(C<sub>5</sub>H<sub>5</sub>)<sub>2</sub>.The reacton rate ofheteronuclear clusters is faster than that with homonuclear clusters.The effect of tempera-ture and pressure on hydroformylation of ethylene with〔PhCH<sub>2</sub>Me<sub>3</sub>〕〔FeCo<sub>3</sub>(CO)<sub>12</sub>〕ascatalyst was studied.The experimental results.show that the conversion of ethylene exceeds90% with a selectivity up to 95% at temperature 130℃ and pressure 3.9 MPa.When studiedwith high pressure in situ infrared spectroscopic method,PhCCo<sub>3</sub>(CO)<sub>9</sub> was found to havehigher thermostability than 〔PhCH<sub>2</sub>Me<sub>3</sub>N〕〔FeCo<sub>3</sub>(CO)<sub>12</sub>〕. 展开更多
关键词 FECO faster SELECTIVITY tempera spectroscopic CRYSTALLINE CATALYZED silica deals CARBONYL
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部