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A review on nitrogen transformation and conversion during coal pyrolysis and combustion based on quantum chemical calculation and experimental study 被引量:3
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作者 Tingting Jiao Huiling Fan +6 位作者 Shoujun Liu Song Yang Wenguang Du Pengzheng Shi Chao Yang Yeshuang Wang Ju Shangguan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第7期107-123,共17页
The emission of NOx during coal combustion contributes to the formation of acid rain and photochemical smog,which would seriously affect the quality of atmospheric environment.Therefore,the decrease of NOx is of great... The emission of NOx during coal combustion contributes to the formation of acid rain and photochemical smog,which would seriously affect the quality of atmospheric environment.Therefore,the decrease of NOx is of great importance for improving the efficient utilization of coal.The present review comprehensively summarized the influence factors and mechanisms of migration and transformation of nitrogen during the coal pyrolysis and combustion based on experimental study and quantum chemical calculation.Firstly,in the process of pyrolysis:the occurrence state and transformation of nitrogen were concluded.The influence of temperature,atmosphere,heating rate and catalyst on formation of NOx precursor and nitrogen migration path at the molecular level were summarized;Secondly,during the process of combustion:the influence of temperature,ambient oxygen concentration,physical structure of coal char,catalyst on heterogeneous oxidation of char(N)were summarized;The effects of char surface properties,catalyst and ambient atmosphere on heterogeneous reduction of NOx were also concluded.Based on the quantum chemical calculation,the reaction path of heterogeneous oxidation of char-N and heterogeneous reduction of NOx were described in detail.Current studies focus more on the generation of HCN and NH3,but in order to reduce the pollution of NOx from the source,it is necessary to further improve the process conditions and the optimal formula of producing more N2 during pyrolysis,as well as clarify the path of the generation of N2.Experiments study and quantum chemistry calculation should be combined to complete the research of directional nitrogen reduction during pyrolysis and denitration during combustion. 展开更多
关键词 Coal combustion PYROLYSIS ENVIRONMENT Nitrogen oxides Quantum chemical calculation
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Hydrothermal Synthesis,Crystal Structure,Spectrum Properties and Quantum Chemical Calculation of a Trinuclear Copper(Ⅱ) Complex with 3-(Pyridin-2-yl)-1,2,4-triazole 被引量:1
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作者 李昶红 李薇 +1 位作者 李玉林 杨颖群 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第8期1089-1094,共6页
A three-dimensional framework copper(Ⅱ) coordination polymer with copper carbonate basic and 3-(pyridin-2-yl)-1,2,4-triazole (Hpt) has been hydrothemally synthesized.The complex (2,C14 H10 CuN8 ·3H2 O) c... A three-dimensional framework copper(Ⅱ) coordination polymer with copper carbonate basic and 3-(pyridin-2-yl)-1,2,4-triazole (Hpt) has been hydrothemally synthesized.The complex (2,C14 H10 CuN8 ·3H2 O) crystallizes in tetragonal,space group P4 2 /n,a=2.08581(12),b=2.08581(12),c=0.72331(4) nm,M r=761.73,V=3.1468(3) nm 3,Dc=1.608 g/cm 3,Z=4,F(000)=1552,GOOF=1.07,R=0.0515 and wR=0.1689.Every asymmetric unit molecular structure of the complex is composed with one copper ion,one and half water molecules and two Hpt molecules.Each copper ion is coordinated with five nitrogen atoms from four Hpt molecules,forming a distorted square pyramidal geometry.The fluorescence spectrum analysis shows that the title complex at room temperature exhibits intense photoluminescence with maximum emission at 450 nm.The quantum chemistry calculation study on the complex has been performed.The stability,some frontier molecular orbital energies and composition characteristics of some frontier molecular orbitals of the complex have been investigated. 展开更多
关键词 trinuclear copper complex hydrothermal synthesis spectrum properties quantum chemical calculation
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QUANTUM CHEMICAL CALCULATIONS ON THE ELECTRONIC STRUCTURE AND SPECTRA OF[Mo_3O_4-nSn]^(4+)(n=O-4)CLUSTER CATIONS
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作者 Zhi Ru LI Qian Shu LI Ji Kang FANG Zhi Ren ZHENG Jun ZHENG Department of Chemistry,Jilin University,Changchun,130023 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第1期43-46,共4页
The electronic structure and spectra of [Mo3O4-nSn]^(4+)(n=0-4) cations were calculated by means of INDO/CI quantum chemistry method to account for the experimental data of their spectra in water solutions.
关键词 HOMO n=O-4)CLUSTER CATIONS Ho LUMO N QUANTUM chemical calculationS ON THE ELECTRONIC STRUCTURE AND SPECTRA OF[Mo3O4-nSn MO
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Formation and dissociation of protonated cytosine–cytosine base pairs in i-motifs by ab initio quantum chemical calculations
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作者 张小虎 黎明 +1 位作者 王延颋 欧阳钟灿 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期189-192,共4页
Formation and dissociation mechanisms of C-C+ base pairs in acidic and alkaline environments are investigated, employing ab initio quantum chemical calculations. Our calculations suggest that, in an acidic environmen... Formation and dissociation mechanisms of C-C+ base pairs in acidic and alkaline environments are investigated, employing ab initio quantum chemical calculations. Our calculations suggest that, in an acidic environment, a cytosine monomer is first protonated and then dimerized with an unprotonated cytosine monomer to form a C-C+ base pair; in an alkaline environment, a protonated cytosine dimer is first unprotonated and then dissociated into two cytosine monomers. In addition, the force for detaching a C-C+ base pair was found to be inversely proportional to the distance between the two cytosine monomers. These results provide a microscopic mechanism to qualitatively explain the experimentally observed reversible formation and dissociation of i-motifs. 展开更多
关键词 ab initio quantum chemical calculation I-MOTIF protonated cytosine-cytosine base pair
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Quantum Chemical Calculations of the Structure,Property and Stability of Penta-coordinated Carbonium Ions Derived from Normal Butane
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作者 Tao Haiqiao Long Jun +3 位作者 Zhou Han Xie Chaogang Dai Zhenyu Wei Xiaoli 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2009年第2期27-30,共4页
The structure and energy of the carbonium ions formed upon protonation of butane were studied by the DFT methods. Four stable structures are identified for the protonated form of n-butane, the energy increases in the ... The structure and energy of the carbonium ions formed upon protonation of butane were studied by the DFT methods. Four stable structures are identified for the protonated form of n-butane, the energy increases in the following order: C2HC3〈C1HC2〈C2HH〈C1HH, and the stability decreases in the following order C2HC3〉C1HC2〉C2HH〉C1HH. The stability of the penta-coordinated carbonium ions may be explained by the electron distribution in the three-center-two-electron bonds. The delocalization of the penta-coordinated carbonium ion CHC with three-center-two-electron bonds on positive charges was stronger than that of the penta-coordinated earbonium ion CHH with three-center-two-electron bonds and its stability was higher than that of the penta-coordinated carbonium ion CHH with three-center-two-electron bonds. 展开更多
关键词 N-BUTANE penta-coordinated carbonium ions STRUCTURE quantum chemical calculation
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Raman spectroscopy and quantum chemical calculation on YCl_(3)-KCl molten salt system
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作者 Can Xu Xian-Wei Hu +5 位作者 Jiang-Yu Yu Peng-Wei Li Ai-Min Liu Shao-Hua Luo Zhong-Ning Shi Zhao-Wen Wang 《Rare Metals》 SCIE EI CAS CSCD 2023年第11期3886-3896,共11页
The knowledge on the ionic structure of YCl_(3)-KCl molten system is of guiding significance for the practical production of yttrium metals and yttrium alloys via molten salt electrolysis using this system as electrol... The knowledge on the ionic structure of YCl_(3)-KCl molten system is of guiding significance for the practical production of yttrium metals and yttrium alloys via molten salt electrolysis using this system as electrolyte.In this paper,the theoretical Raman spectra of the ionic groups which may exist in YCl_(3)-KCl molten system are simulated by quantum chemical calculation using Gaussian09 and Gauss View 5.0 programs based on density functional theory(DFT).Then the ionic structures of 20 mol%-60 mol%YCl_(3)-KCl molten salt systems are studied by comparing the Raman shift values of the bands in the theoretical Raman spectra of different ionic groups with the experimental spectra of this system.YCl_(6)^(3-),Y_(2)Cl_(7)^(-),Y_(2)Cl_(8)^(2-)and Y_(2)Cl_(9)^(3-)are thought to exist in the molten system.With the increase of temperature,the relative content of YCl_(6)^(3-)ionic groups increases while those of Y_(2)Cl_(7)^(-),Y_(2)Cl_(8)^(2-)and Y_(2)Cl_(9)^(3-)ionic groups decrease.Moreover,the"lifetime"of all ionic groups decreases within the temperature range of 692-730℃.Meanwhile,the relative contents of Y_(2)Cl_(7)^(-),Y_(2)Cl_(8)^(2-)and Y_(2)Cl_(9)^(3-)increase with the increase of YCl_(3)content,while that of YCl_(6)^(3-)decreases.The wave function analysis of the four ionic groups(YCl_(6)^(3-),Y_(2)Cl_(7)^(-),Y_(2)Cl_(8)^(2-),and Y_(2)Cl_(9)^(3-))is carried out by Multiwfn program.The net charge in each group,the direction of electron migration during the formation of each group,the sites where electrophilic and nucleophilic reactions are most likely to occur in each ionic group,and the order of bond breaking during chemical reactions for the four groups are obtained. 展开更多
关键词 YCl_(3)-KCl molten salt Ionic structure Raman spectroscopy Quantum chemical calculation Wave function analysis
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Synthesis, Characterization, Crystal Structure and Quantum Chemical Calculation of Novel Compound 1,3-Dimethyl-2-ferrocenylmethylbenzimidazolium Iodide 被引量:4
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作者 张晶 杨秉勤 +2 位作者 朱海燕 李涛 文振翼 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2006年第5期637-641,共5页
A novel benzimidazole derivative, 1,3-dimethyl-2-ferrocenylmethylbenzimidazolium iodide (1) was synthesized and characterized by elemental analysis, MS, IH NMR and IR spectra. Its crystal structure was determined by... A novel benzimidazole derivative, 1,3-dimethyl-2-ferrocenylmethylbenzimidazolium iodide (1) was synthesized and characterized by elemental analysis, MS, IH NMR and IR spectra. Its crystal structure was determined by X-ray single crystal diffraction, and the title compound belongs to monoclinic system with space group P2(1)/c. According to the crystal structure, the quantum chemistry calculation was performed by Gaussian 03 program, and full geometry optimizations of the title compound were carried out with DFT method at B3LYP/6-31G level. Its structure, stability, frontier molecular orbital components and net charge distribution were discussed. 展开更多
关键词 1 3-dimethyl-2-ferrocenylmethylbenzimidazolium SYNTHESIS crystal structure quantum chemical calculation
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A Polymer {[Cu^Ⅱ(Hpb)(mal)]H=O}n: Magnetic Studies and Quantum Chemical Calculation for Its Monomer 被引量:1
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作者 朱海燕 周利君 +2 位作者 王尧宇 文振翼 王育彬 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2006年第3期321-325,共5页
{[Cu^Ⅱ(Hpb)(mal)]H=O}n (Hpb=2-2'-pyridylbenzimidazole, mal=maleic acid) is a helical chain-like polymer complex. In order to investigate the electronic structure of the complex, the monomer Cu^Ⅱ(Hpb)(mal)... {[Cu^Ⅱ(Hpb)(mal)]H=O}n (Hpb=2-2'-pyridylbenzimidazole, mal=maleic acid) is a helical chain-like polymer complex. In order to investigate the electronic structure of the complex, the monomer Cu^Ⅱ(Hpb)(mal) was obturated with different functional groups respectively. For these selective segments, the geometry optimizations were conducted by using hybrid DFT (B3LYP)methods to find that the structure obturated with H2O was better consistent with the experiment, and then this model would be used to latter calculations, such as the frontier molecular orbital and the NBO charge population analysis. In addition the magnetic behaviors of this complex were analyzed by experiments and the weak antiferromagnetic couple between copper(Ⅱ) ions was observed. The exchange coupling constant was calculated by DFT based on the spin broken symmetry formalism. The calculated coupling constants were in good agreement with the experimental data. 展开更多
关键词 POLYMER MAGNETIC quantum chemical calculation natural bond orbital
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THE MASS SPECTRA OF AROMATIC CONJUGATED POLYENIC ACID,METHYL BENZOATE,METHYL PHENYL KETONE,BENZONITRILE AND ANILINE AND THEIR QUANTUM CHEMICAL CALCULATIONS
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作者 赖柱根 梁德声 房耀仁 《Science China Chemistry》 SCIE EI CAS 1982年第10期1035-1043,共9页
A quantitative interpretation of mass spectra of complex organic compounds so far is notvery perfect and needs some further investigation. In this paper a mechanism of cleft-rate-determining-steps of aromatic conjugat... A quantitative interpretation of mass spectra of complex organic compounds so far is notvery perfect and needs some further investigation. In this paper a mechanism of cleft-rate-determining-steps of aromatic conjugated polyenic acid, methyl benzoate, methyl phenyl ketone,benzonitrile and aniline is proposed, and various quantum parameters of molecular ions ofaromatic conjugated polyenic compounds, together with their framents are calculated bymeans of CNDO/2 method. Through the process of calculation, the peak-height of mass spectracan be quantitatively interpreted, which means that the main factors which influence the cleftforms of simple cleavage of mass spectra of conjugated compounds given by the authorsmight be true to some extent. 展开更多
关键词 兀一 THE MASS SPECTRA OF AROMATIC CONJUGATED POLYENIC ACID METHYL BENZOATE METHYL PHENYL KETONE BENZONITRILE AND ANILINE AND THEIR QUANTUM chemical calculationS CNDO
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Calculations of Chemical Reaction Dynamics for D+ H_2(j_i,ν_i=0)→DH(j_f, ν_f=0) + H
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作者 Li Qin SI(Editorial Office of Natural Science, Yantai Normal University, Yantai, 264025) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第2期153-156,共4页
The constant Centrifugal potential approximation is Corrected so as to apply to the reactions of rotational excited reactants for D + H2 (j,, νi = 0 ) -DH(jf, νf = 0) + H. Our results show that the contributions fro... The constant Centrifugal potential approximation is Corrected so as to apply to the reactions of rotational excited reactants for D + H2 (j,, νi = 0 ) -DH(jf, νf = 0) + H. Our results show that the contributions from ji≠0 and Ωi terms are not negligible. 展开更多
关键词 DH j_f H2 j_i i=0 calculations of chemical Reaction Dynamics for D
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Synthesis,Crystal Structure and Quantum Chemical Investigation of Bis-Schiff Base Compounds Derived from2-phenyl-1,2,3-triazole-4-carboxaldehyde with Diamine 被引量:2
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作者 XIE Ling LIU Gang WANG Yan WANG Ji-De CHEN Jun-Feng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第5期616-621,共6页
Two new schiff base N,N'-bis((2-phenyl-2H-1,2,3-triazol-4-yl)methylene)-1,3-propanediamine (1) and N,N'-bis((2-phenyl-2H-1,2,3-triazol-4-yl)methylene) -1,4-butanediamine (2) were synthesized by condensat... Two new schiff base N,N'-bis((2-phenyl-2H-1,2,3-triazol-4-yl)methylene)-1,3-propanediamine (1) and N,N'-bis((2-phenyl-2H-1,2,3-triazol-4-yl)methylene) -1,4-butanediamine (2) were synthesized by condensation of 2-phenyl-1,2,3-triazole-4-carboxaldehyde with diamine, and characterized by elemental analysis, IR, IH NMR and MS spectra. Their crystal structures were determined by X-ray single crystal diffraction. Both crystals belong to the monoclinic system, space group P21/c. For compound 1(C21H20N8, Mr=384.45): a = 16.314(3), b =5.7168(11), c = 21.316(4) A, β = 105.3(2)°, Z = 4, V = 1917.6(7) A^3, De =1.332 g/cm^3, F(000) = 808,μ = 0.086 mm 1, R = 0.0533 and wR = 0.1460; for compound 2 (C22H22N8, Mr=398.48): a = 8.6156(17), b = 5.2964(11), c = 22.665(5)A, β = 100.54(3)°, Z = 2, V = 1016.8(4) A^3, De= 1.302 g/cm^3, F (000) = 420, μ = 0.083 mm^-1, R = 0.0373 and wR = 0.1155. Based on the crystal data, quantum chemistry calculation was performed on the two title compounds by means of Gaussian 98 program. The molecular orbital energies and atomic net charges population were obtained. Furthermore, we antilyzed their active atoms. The investigation can serve as a theoretical guide to study the synthesis and activity of the title compounds. 展开更多
关键词 schiff base crystal structure quantum chemical calculation
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Synthesis, Crystal Structure,Characterization and Quantum Chemical Studies on 1N-Acetyl-3-(2,4-dichloro-5-fluoro- phenyl)-5-(p-methyl-phenyl)-2-pyrazoline
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作者 郭焕美 张静 +1 位作者 赵朴素 建方方 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第12期1491-1498,共8页
1N-Acetyl-3-(2,4-dichloro-5-fluoro-phenyl)-5-(p-methyl-phenyl)-2-pyrazoline has been synthesized and characterized by elemental analysis, IR, UV-Vis and X-ray single-crystal diffraction. Ab intio calculations have... 1N-Acetyl-3-(2,4-dichloro-5-fluoro-phenyl)-5-(p-methyl-phenyl)-2-pyrazoline has been synthesized and characterized by elemental analysis, IR, UV-Vis and X-ray single-crystal diffraction. Ab intio calculations have been carded out for the compound by using both B3LYP and HF methods at the 6-31G^* basis set. The calculated results show that the predicted geometry can well reproduce the structural parameters. The electronic absorption spectra calculated by B3LYP/6-31G^* method are approximate to the experiments and the Natural Bond Orbital (NBO) analyses suggest that the above electronic transitions are mainly assigned to n→π^* and π→π^* transitions. CIS-HF/6-31G^* method is not suitable to predict the electronic spectra for the title compound. The calculation of the second order optical nonlinearity was carded out, giving the value of molecular hyperpolarizability equal to 2.194^+ 10^-30 esu. On the basis of vibrational analyses, the thermodynamic properties of the compound at different temperature have been calculated, revealing the correlation between C p, m^0, S m^0, H m^0 and temperature. 展开更多
关键词 SYNTHESIS crystal structure quantum chemical calculation electronic absorption spectra thermodynamic property
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Structural Evolution and Electronic Properties of Au2Gen-/0(n=1-8) Clusters: Anion Photoelectron Spectroscopy and Theoretical Calculations
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作者 Sheng-Jie Lu Hong-Guang Xu +1 位作者 Xi-Ling Xu Wei-Jun Zheng 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2019年第2期229-240,I0003,共13页
Investigating the structures and properties of Au-Ge mixed clusters can give insight into the microscopic mechanisms in gold-catalyzed Ge films and can also provide valuable information for the production of germanium... Investigating the structures and properties of Au-Ge mixed clusters can give insight into the microscopic mechanisms in gold-catalyzed Ge films and can also provide valuable information for the production of germanium-based functional materials. In this work, size-selected anion photoelectron spectroscopy and theoretical calculations were used to explore the structural evolution and electronic properties of Au2Gen^-/0 (n=1-8) clusters. It is found that the two Au atoms in Au2Gen^-/0 (n=1-8) showed high coordination numbers and weak aurophilic interactions. The global minima of Au2Gen- anions and Au2Gen neutrals are in spin doublet and singlet states, respectively. Au2Gen- anions and Au2Gen neutrals showed similar structural features, except for Au2Ge4^-/0 and Au2Ge5^-/0. The C2v symmetric V-shaped structure is observed for Au2Ge1^-/0, while Au2Ge2^-/0 has a C2v symmetric dibridged structure. Au2Ge3^-/0 can be viewed as the two Au atoms attached to different Ge-Ge bonds of Ge3 triangle. Au2Ge4- has two Au atoms edge-capping Ge4 tetrahedron, while Au2Ge4 neutral adopts a C2v symmetric double Au atoms face-capping Ge4 rhombus. Au2Ge5-8^-/0 show triangular, tetragonal, and pentagonal prism-based geometries. Au2Ge6 adopts a C2v symmetric tetragonal prism structure and exhibits σ plus π double bonding characters. 展开更多
关键词 Photoelectron spectroscopy Transition metal Germanium cluster Structural evolution Quantum chemical calculations
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Synthesis, Structure and Quantum Mechanical Calculations of Methyl 2-(5-((Quinolin-8-yloxy)-methyl)-1,3,4-oxadiazol-2-ylthio)-acetate
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作者 AAMER SAEED FOUZIA PERVEEN +2 位作者 NAEEM ABBAS SIDRA JAMAL ULRICH FL?RKE 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第6期858-870,共13页
The title compound was synthesized by the base catalyzed reaction of 5-((quinolin- 8-yloxy)methyl)-1,3,4-oxadiazole-2(3H)-thione with methyl chloroacetate. The structure was supported by the spectroscopic data a... The title compound was synthesized by the base catalyzed reaction of 5-((quinolin- 8-yloxy)methyl)-1,3,4-oxadiazole-2(3H)-thione with methyl chloroacetate. The structure was supported by the spectroscopic data and unambiguously confirmed by single-crystal X-ray diffraction studies. It crystallizes from a methanol solution in the triclinic space group Pi with unit cell dimensions a = 7.4509(9), b = 10.2389(12), c = 12.2299(15)A, a = 74.771(2), β = 77.956(2), 7 = 69.263(2)°, V = 834.98(17) A3 and Z = 2. In order to gain some valuable insights into the molecular structure, the quantum mechanical calculations were performed using both HF and time-dependent density functional theory at the B3LYP/6-31G(d,p) level. The molecular geometry from X-ray determination of the title compound in the ground state has been compared using the Hartree-Fock (HF) and density functional theory (DFT) with the 6-31G(d) basis set. The calculated results show that the DFT and HF can well reproduce the structure of the title compound. The energetic behavior of the title compound was examined using the B3LYP method with the 6-31G(d) basis set. The harmonic vibrational frequencies calculated have been compared with the experimental FTIR and FT-Raman spectra. The restricted Hartree-Fock and density functional theory-based nuclear magnetic resonance (NMR) calculation procedure was also performed, and it was used for assigning the 13C and 1H NMR chemical shifts of the title compound. Moreover, molecular electrostatic potential and thermodynamic parameters of the title compound were investigated by theoretical calculations. 展开更多
关键词 methyl 2-(5-((quinolin-8-yloxy)methyl)-1 3 4-oxadiazol-2-ylthio)acetate CRYSTALSTRUCTURE CONFORMER quantum chemical calculations vibrational studies
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Spectroscopic characterization of chain-to-ring structural evolution in platinum carbide clusters
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作者 Yu Zhang Shihu Du +5 位作者 Zhi Zhao Haiyan Han Gang Li Jinghan Zou Hua Xie Ling Jiang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期529-534,I0014,共7页
Metal carbides play an important role in catalysis and functional materials.However,the structural characterization of metal carbide clusters has been proven to be a challenging experimental target due to the difficul... Metal carbides play an important role in catalysis and functional materials.However,the structural characterization of metal carbide clusters has been proven to be a challenging experimental target due to the difficulty in size selection.Here we use the size-specific photoelectron velocity-map imaging spectroscopy to study the structures and properties of platinum carbide clusters.Quantum chemical calculations are carried out to identify the structures and to assign the experimental spectra.The results indicate that the cluster size of the chain-to-ring structural evolution for the PtC_(n)^(-)anions occurs at n=14,whereas that for the PtC_(n) neutrals at n=10,revealing a significant effect of charge on the structures of metal carbides.The greatest importance of these building blocks is the strong preference of the Pt atom to expose in the outer side of the chain or ring,exhibiting the active sites for catalyzing potential reactions.These findings provide unique spectroscopic snapshots for the formation and growth of platinum carbide clusters and have important implications in the development of related single-atom catalysts with isolated metal atoms dispersed on supports. 展开更多
关键词 CATALYSIS Functional material Metal carbide Photoelectron velocity-map imaging spectroscopy Quantum chemical calculation
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Drug adulteration analysis based on complexation with cyclodextrin and metal ions using ion mobility spectrometry
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作者 Zhigang Liang Huanhuan Wang +3 位作者 Fangling Wu Longfei Wang Chenwei Li Chuan-Fan Ding 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第3期287-295,共9页
Drug adulteration and contamination are serious threats to human health therefore,their accurate monitoring is very important.Allopurinol(Alp)and theophylline(Thp)are commonly used drugs for the treatment of gout and ... Drug adulteration and contamination are serious threats to human health therefore,their accurate monitoring is very important.Allopurinol(Alp)and theophylline(Thp)are commonly used drugs for the treatment of gout and bronchitis,while their isomers hypoxanthine(Hyt)and theobromine(Thm)have no effect and affect the efficacy of the drug.In this work,the drug isomers of Alp/Hyt and Thp/Thm are simply mixed withα-,β-,γ-cyclodextrin(CD)and metal ions and separated using trapped ion mobility spectrometry-mass spectrometry(TIMS-MS).TIMS-MS results showed that Alp/Hyt and Thp/Thm isomers could interact with CD and metal ions and form corresponding binary or ternary complexes to achieve their TIMS separation.Different metal ions and CDs showed different separation effect for the isomers,among which Alp and Hyt could be successfully distinguished from the complexes of[Alp/Hyt+γ-CD+Cu–H]^(+)with separation resolution(RP–P)of 1.51;whereas Thp and Thm could be baseline separated by[Thp/Thm+γ-CD+Ca–H]^(+)with RP–P of 1.96.Besides,chemical calculations revealed that the complexes were in the inclusion forms,and microscopic interactions were somewhat different,making their mobility separation.Moreover,relative and absolute quantification was investigated with an internal standard to determine the precise isomers content,and good linearity(R^(2)>0.99)was obtained.Finally,the method was applied for the adulteration detection where different drugs and urine were analyzed.In addition,due to the advantages of fast speed,simple operation,high sensitivity,and no chromatographic separation required,the proposed method provides an effective strategy for the drug adulteration detection of isomers. 展开更多
关键词 Drug isomer ADULTERATION Separation Ion mobility chemical calculations
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Four new lanostane triterpenoids featuring extendedπ-conjugated systems from the stems of Kadsura coccinea
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作者 Qi-Qi Zhang Kun Hu +1 位作者 Han-Dong Sun Pema-Tenzin Puno 《Natural Products and Bioprospecting》 CSCD 2023年第1期607-614,共8页
Four new 14(13→12)-abeolanostane triterpenoids featuring extendedπ-conjugated systems,kadcoccitanes E-H(1-4),were obtained from the stems of Kadsura coccinea through using a HPLC−UV-guided approach.Their structural ... Four new 14(13→12)-abeolanostane triterpenoids featuring extendedπ-conjugated systems,kadcoccitanes E-H(1-4),were obtained from the stems of Kadsura coccinea through using a HPLC−UV-guided approach.Their structural and configurational determination was accomplished through extensive spectroscopic analysis coupled with quantum chemical calculations.Kadcoccitanes E-H were tested for their cytotoxic activities against five human tumor cell lines(HL-60,A-549,SMMC-7721,MDA-MB-231,SW-480)but none of them exhibited activities at the concentration 40μM. 展开更多
关键词 Kadsura coccinea Lanostane triterpenoids Extendedπ-conjugated systems Quantum chemical calculation
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Synthesis,Structure and Chemical Bonding of Polyantimony Clusters Containing Coinage Metals[M_(2)Sb_(14)]^(4-)(M=Cu,Ag)
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作者 Wei-Xing Chen Yu-He Xu +4 位作者 Cui-Cui Wang Lei Qiao Zi-Yan Guo Wen-Juan Tian Zhong-Ming Sun 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第6期617-622,共6页
Binary polyantimony clusters,namely[Cu_(2)Sb_(14)]^(4–) and [Ag_(2)Sb_(14)]^(4–),containing coinage metals,were successfully synthesized and characterized,in which two homoatomic Sb73–subunits are bridged by two co... Binary polyantimony clusters,namely[Cu_(2)Sb_(14)]^(4–) and [Ag_(2)Sb_(14)]^(4–),containing coinage metals,were successfully synthesized and characterized,in which two homoatomic Sb73–subunits are bridged by two coinage metals in η^(4):η^(1) and η^(1):η^(1) coordination modes,respectively.In[M_(2)Sb_(14)]^(4-),two bridging Cu ions and two Sb atoms form a planar rhombic unit,which was revealed to have antiaromatic properties by theoretical calculations.Further electron structure and bonding analysis confirmed the presence of delocalized bonds in the rhombic unit and the metallophilic interaction between two formal M^(+) ions. 展开更多
关键词 Polyantimony cluster Copper SILVER ANTIAROMATICITY Metallophilic interaction Quantum chemical calculations
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Theoretical Study on Decomposition of CF3OH Catalyzed by Water Dimer and Ammonia 被引量:1
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作者 龙波 谭兴凤 +2 位作者 隆正文 任达森 张为俊 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第1期16-21,I0003,共7页
The G3 and CBS-QB3 theoretical methods are employed to study the decomposition of CF3OH into FCFO and HF by water, water dimmer, and ammonia. The decomposition of CF3OH into FCFO and HF is unlikely to occur in the atm... The G3 and CBS-QB3 theoretical methods are employed to study the decomposition of CF3OH into FCFO and HF by water, water dimmer, and ammonia. The decomposition of CF3OH into FCFO and HF is unlikely to occur in the atmosphere due to the high activated energy of 88.7 k J/mol at the G3 level of theory. However, the computed results predict that the barrier for unimolecular decomposition of CF3OH is decreased to 25.1 kJ/mol from 188.7 k J/mol with the aid of NH3 at the G3 level of theory, which shows that the ammonia play a strong catalytic effect on the split of CF3OH. In addition, the calculated rate constants show that the decomposition of CF3OH by NH3 is faster than those of H2O and the water dimmer by 10^9 and 10^5 times respectively. The rate constants combined with the corresponding concentrations of these species demonstrate that the reaction CF3OH with NH3 via TS4 is of great importance for the decomposition of CF3OH in the atmosphere. 展开更多
关键词 CF3OH AMMONIA Quantum chemical calculation Rate constant Reaction mechanism
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Syntheses,crystal structures,and quantum chemistry calculation of two Ni(Ⅱ)coordination polymers
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作者 LI Xiumei HUANG Yanju +1 位作者 LIU Bo PAN Yaru 《无机化学学报》 SCIE CAS 2024年第10期2031-2039,共9页
Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmeth... Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmethyl)butane(bib)by a hydrothermal method,respectively.X⁃ray crystallography reveals a 2D network constructed by six⁃coordinated Ni(Ⅱ)􀃭centers,bib,and Hpdc2-ligands in complex 1,while a 2D network is built by Ni(Ⅱ)and bib ligands in 2.Furthermore,the quantum⁃chemical calculations have been performed on‘molecular fragments’extracted from the crystal structure of 1 using the PBE0/LANL2DZ method in Gaussian 16 and the VASP program.CCDC:2343794,1;2343798,2. 展开更多
关键词 coordination polymer nickel(Ⅱ)complex crystal structure quantum⁃chemical calculation
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