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Is There Hysteresis in Unemployment in OECD Countries? Evidence From Panel Unit Root Test With Structural Breaks
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作者 Meliha Ener Feyza Ariea 《Chinese Business Review》 2011年第4期294-304,共11页
This study tests the hysteresis hypothesis of unemployment in fifteen OECD countries by using panel unit root tests which allow for structural breaks. We apply annual unemployment rates covering 1985-2008 periods. We ... This study tests the hysteresis hypothesis of unemployment in fifteen OECD countries by using panel unit root tests which allow for structural breaks. We apply annual unemployment rates covering 1985-2008 periods. We test whether unemployment rates are stationary by using second generation tests which allow cross section dependency among series and panel unit root test based on structural break advanced by Carrion-i-Silvestre, Barrio-Castro and Lopez-Bazo (2005). We find series as a stationary process with structural breaks according to Carrion-i Silvestre et al. (2005) test, while we find series as unit root process with second generation panel unit root test. According to the Carrion-i Silvestre et al. (2005) test, we find the evidence of absence of hysteresis in analyzed countries. As a result, temporary shocks have temporary effects on unemployment instead of permanent effect. Structural factors can affect the natural rate of unemployment and, therefore, unemployment would be stationary around a process that is subject to structural breaks. So, there still exists a unique natural rate of unemployment to which the economy eventually will converge. 展开更多
关键词 structural break unemployment cross-section dependence panel unit root tests
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Structural, mechanical, and electronic properties of 25 kinds of Ⅲ–Ⅴbinary monolayers: A computational study with first-principles calculation 被引量:2
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作者 Xue-Fei Liu Zi-Jiang Luo +5 位作者 Xun Zhou Jie-Min Wei Yi Wang Xiang Guo Bing Lv Zhao Ding 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第8期258-269,共12页
Using first-principle calculations, we investigate the mechanical, structural, and electronic properties and formation energy of 25 kinds of Ⅲ–V binary monolayers in detail. A relative radius of the binary compound ... Using first-principle calculations, we investigate the mechanical, structural, and electronic properties and formation energy of 25 kinds of Ⅲ–V binary monolayers in detail. A relative radius of the binary compound according to the atomic number in the periodic table is defined, and based on the definition, the 25 kinds of Ⅲ–V binary compounds are exactly located at a symmetric position in a symmetric matrix. The mechanical properties and band gaps are found to be very dependent on relative radius, while the effective mass of holes and electrons are found to be less dependent. A linear function between Young’s modulus and formation energy is fitted with a linear relation in this paper. The change regularity of physical properties of B–V(V = P, As, Sb, Bi) and Ⅲ–N(Ⅲ = Al, Ga, In, Tl) are found to be very different from those of other Ⅲ–V binary compounds. 展开更多
关键词 DENSITY FUNCTIONAL theory -Ⅴbinary monolayers BAND structure MECHANICAL properties
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Synthesis and Structural Characterization of 2,3-Bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol 被引量:3
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作者 毕福强 王伯周 +4 位作者 樊学忠 许诚 葛忠学 刘庆 张国防 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第3期415-419,共5页
2,3-Bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol(C6H12N2O8) was synthesized by condensation,cyclization,oxidative dimerization and deketalization of nitromethane with a total yield of 42.4%.The structure of the t... 2,3-Bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol(C6H12N2O8) was synthesized by condensation,cyclization,oxidative dimerization and deketalization of nitromethane with a total yield of 42.4%.The structure of the title compound was characterized by 1H NMR,13C NMR,FT-IR,elementary analysis,and X-ray single-crystal diffraction analysis,which reveals that the title compound crystallizes in triclinic,space group P with a = 0.6324(2),b = 0.6454(3),c = 0.7062(3) nm,α= 111.550(4),β= 95.505(4),γ= 113.395(4)°,V = 0.23595(16) nm3,Z = 1,Mr = 240.18,Dc = 1.690 g·cm-3,μ = 0.159 mm-1,F(000) = 126,R = 0.0304 and wR = 0.0907. 展开更多
关键词 2 3-bis(hydroxymethyl)-2 3-dinitro-1 4-butanediol SYNTHESIS characterization crystal structure
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Auxiliary Ligand-tuned Structural Variation of Cd(Ⅱ)Coordination Polymers:Synthesis,Crystal Structures and Luminescent Properties 被引量:2
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作者 赵帅 王浩 +3 位作者 刘洋 伍一波 王亚飞 郭文莉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第11期1797-1804,共8页
Two new Cd(Ⅱ) coordination polymers, [Cd(PT)(1,4-BDC)0.5]n (1) and [Cd(PT) (1,3-BDC)0.5]n (2) (HPT = 3-(pyridin-2-yl)-1,2,4-triazole, 1,4-H2BDC = 1,4-benzenedicarboxylic acid, 1,3-H2BDC = 1,3-benzene... Two new Cd(Ⅱ) coordination polymers, [Cd(PT)(1,4-BDC)0.5]n (1) and [Cd(PT) (1,3-BDC)0.5]n (2) (HPT = 3-(pyridin-2-yl)-1,2,4-triazole, 1,4-H2BDC = 1,4-benzenedicarboxylic acid, 1,3-H2BDC = 1,3-benzenedicarboxylic acid), have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction as well as elemental analysis and IR. Complexes 1 and 2 are both three-dimensional coordination polymers with two-dimensional sheet structures bridged by the deprotonated carboxylate ligands. In 1, 1,4-BDC2- bridges the layered network to generate a quadrangular framework, and 2 owns a sexangular framework, which was caused by the different steric hindrance between 1,4-BDC^2- and 1,3-BDC^2-. Their thermal stabilities and photoluminescent properties have been also investigated. 展开更多
关键词 3-(pyridin-2-yl)-1 2 4-triazole cadmium complex crystal structure
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Syntheses and Structural Characterization of Dimethyltin Complexs of N-(3-Methoxysalicylidene)-α-amino Acid 被引量:3
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作者 党艳秋 杨红军 田来进 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第4期479-484,共6页
Three new dimethyltin complexes of N-(3-methoxysalicylidene)-α-amino acid,(CH3)2Sn(3-CH3O-2-OC6H3CH=NCHRCOO)(R = H,1;CH3,2;(CH3)2CH,3),have been synthe-sized by treating dimethyltin dichloride with the pota... Three new dimethyltin complexes of N-(3-methoxysalicylidene)-α-amino acid,(CH3)2Sn(3-CH3O-2-OC6H3CH=NCHRCOO)(R = H,1;CH3,2;(CH3)2CH,3),have been synthe-sized by treating dimethyltin dichloride with the potassium salt of the ligand and characterized by elemental analysis,IR and 1H NMR spectra.The crystal structure of [(CH3)2Sn(3-CH3O-2-OC6H3CH=NCH2COO)(CH3OH)]2 H2O(1a),formed from methanol solution of 1,has been deter-mined.The crystal belongs to the monoclinic system,space group C/2c with a = 20.636(3),b = 7.8854(9),c = 20.668(2) ,β= 113.265(2)°,V = 3089.7(6) 3,Z = 4,Dc = 1.707 g/cm3,= 1.675 mm-1,F(000) = 1592,R = 0.0301 and wR = 0.0841.In complex 1a,the tin atom is six-coordinate and possesses a distorted [SnC2NO3] octahedral geometry with the two methyl groups occupying the trans positions.The weak Sn O interactions and intermolecular hydrogen bonds connected the molecules into an infinite chain. 展开更多
关键词 organotin complex N-(3-methoxysalicyliden)-α-amino acid crystal structure
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Investigation of structural parameters and self-aggregation of Algerian asphaltenes in organic solvents 被引量:2
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作者 Asma Larbi Mortada Daaou Abassia Faraoun 《Petroleum Science》 SCIE CAS CSCD 2015年第3期509-517,共9页
Elemental analysis, Fourier transform infrared (FTIR), 1H-NMR, fluorescence spectroscopy, and surface tension methods have been used to characterize the molecular structure and the aggregation behaviors of two aspha... Elemental analysis, Fourier transform infrared (FTIR), 1H-NMR, fluorescence spectroscopy, and surface tension methods have been used to characterize the molecular structure and the aggregation behaviors of two asphaltenic fractions derived, respectively, from an Alge- rian petroleum well and a corresponding storage tank deposit. Elemental analysis, FTIR, ~H-NMR, and fluores- cence spectroscopy were used to investigate the chemical composition and structural parameters of asphaltenes, while the surface tension method was used to measure the critical micelle concentration (CMC) in organic solvents with different solubility parameters and polarities in order to characterize the asphaltenes' aggregation behaviors. Results show that the unstable asphaltenes fraction extracted from the storage tank deposit possesses a higher polarity (higher heteroatoms content) and a lower aro- maticity than stable asphaltenes from the petroleum well. The CMC results indicate that asphaltenes with high polarity and low aromaticity have a high solubility in polar solvents such as nitrobenzene, whereas asphaltenes with low polarity and high aromaticity are more soluble in solvents with weak polarity, like toluene. It is concludedthat the difference of structure of asphaltene samples and polarity of solvents can lead to difference of aggregation behaviors. 展开更多
关键词 Asphaltenes Algerian petroleum structural parameters - CMC
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Synthesis,Structural Characterization and Properties of Bis(1,5-diamino-1Htetrazolium)3,3'-bis(nitramino)-4,4'-azofurazan 被引量:3
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作者 许诚 毕福强 +3 位作者 张敏 刘庆 丁可伟 葛忠学 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第9期1341-1346,共6页
An energetic salt of bis(l,5-diamino-lH-tetrazolium)3,3"-bis(nitramino)-4, 4x-azo- furazan (C6H10N2206) was synthesized with the total yield of 61.7% by using 3,4-diaminofurazan (DAF) as the starting material... An energetic salt of bis(l,5-diamino-lH-tetrazolium)3,3"-bis(nitramino)-4, 4x-azo- furazan (C6H10N2206) was synthesized with the total yield of 61.7% by using 3,4-diaminofurazan (DAF) as the starting material. The structure of the title compound was confirmed by NMR, IR, elemental analysis and single-crystal X-ray diffraction. It crystallizes in orthorhombic, space group P21/c with a = 10.739(2), b = 6.4765(12), c = 14.138(3) A, fl= 108.787(3)°, V= 930.9(3) A3, Z = 1, Mr= 486.36, Dc = 1.735 g.cm3, μ= 0.15 mm-1, F(000) = 496, R = 0.042 and wR = 0.121. The thermal stability was analyzed by subsequently differential scanning calorimetry (DSC). And the enthalpy of formation and detonation was calculated theoretically, showing the first decomposition temperature was 142.1℃, the enthalpy of formation was 1614.23 kJ.mol1 and the detonation velocity and detonation pressure were 8.781 km.s-1 and 30.7 GPa, respectively. 展开更多
关键词 bis(1 5-diamino-1H-tetrazolium)3 3?-bis(nitramino)-4 4?-azofurazan SYNTHESIS crystal structure furazan derivate
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Structural and Vibrational Study of 2-(Quinolin-8-yloxy)-Acetic Acid based on FT-IR-Raman Spectroscopy and DFT Calculations 被引量:1
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作者 Gerardo R. Arganaraz Elida Romano +1 位作者 Juan Zinczuk Silvia A. Brandan 《Journal of Chemistry and Chemical Engineering》 2011年第8期747-758,共12页
We have prepared the 2-(quinolin-8-yloxy)-acetic acid and characterized it by infrared and Raman spectroscopies in the solid phase. The Density Functional Theory (DFT) method, together with the 6-31G^* and 6-311... We have prepared the 2-(quinolin-8-yloxy)-acetic acid and characterized it by infrared and Raman spectroscopies in the solid phase. The Density Functional Theory (DFT) method, together with the 6-31G^* and 6-311++ G^** basis sets, show that three stable molecules, for the anhydrous and monohydrated compounds were theoretically determined in the gas phase, and that probably the two more stable conformations are present in the solid phase of the monohydrated compound. The harmonic vibrational wavenumbers for the optimized geometries were calculated at B3LYP/6-31G^*and B3LYP/6-311++G^** levels. For a complete assignment of all the observed bands in the vibrational spectra the DFT calculations were combined with Pulay's scaled quantum mechanical force field (SQMFF) methodology in order to fit the theoretical Wavenumber values to the experimental ones. The characteristics of the electronic delocalization of all structures of both forms were performed by using natural bond orbital (NBO), while the corresponding topological properties of electronic charge density are analysed by employing Bader's atoms in molecules theory (AIM). 展开更多
关键词 2-(Quinolin-8-yloxy)-acetic acid vibrational spectra molecular structure force field DFT calculations
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Synthesis and Structural Characterization of Organophosphorus Ylide-1-(3-nitrophenyl)-2-(triphenyl phosphoranylidene)ethanone 被引量:1
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作者 ALIREZA Dadrass ALI Ramazani +6 位作者 AHMAD Poursattar Marjani HOJJATOLLAH Rahchamani HASSAN Nasri Koureh ALI Souldozi SEPIDEH Samiee KATARZYNA lepokura TADEUSZ Lis 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第3期373-378,共6页
The title compound Ph3P=C(H)C(O)PhNO2 (L) has been prepared by the addition of triphenylphosphine in acetone as solvent to 2-bromo-1-(3,nitrophenyl)ethanone followed by the addition of alkaline solution of sod... The title compound Ph3P=C(H)C(O)PhNO2 (L) has been prepared by the addition of triphenylphosphine in acetone as solvent to 2-bromo-1-(3,nitrophenyl)ethanone followed by the addition of alkaline solution of sodium hydroxide. The yellow crystals of the title ylide were grown in methanol/chloroform solution by drop method without stirring at room temperature. The solid state structure of ylide has been established by X-ray crystallography analysis. In the molecule of the title compound, the geometry around the P atom is nearly tetrahedral and the O atom is in synperiplanar orientation to the P atom. The nitrophenyl ring is twisted with respect to the plane of the carbonyl group through an angle of 36.6(1)°. The crystal (C26H20NO3P, Mr = 425.40) belongs to the monoclinic system, space group P21/n with a = 10.889(3), b = 14.467(3), e = 13.872(4)A, β = 103.08(3)°, V = 2128.6(10) A3, Z= 4, T= 100(2) K, R = 0.059 and wR = 0.163 for 3984 observed reflections with I〉 2σ(I). 展开更多
关键词 crystal structure phosphorus yUde 2-bromo-1-(3-nitrophenyl)ethanone triphenylphosphine
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New Advances in Structural Studies of Barium Rare-Earth Fluor-Carbonate Minerals
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作者 Shen Jinchuan Mi JinxiaoChina University of Geosciences , Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1992年第1期21-28,共8页
This paper summarizes the new developments in the study of barium rare-earth fluor-carbonate mineral structures .The second order superstructure of cebaite -(Ce ) was solved by using high power X-ray single crystal di... This paper summarizes the new developments in the study of barium rare-earth fluor-carbonate mineral structures .The second order superstructure of cebaite -(Ce ) was solved by using high power X-ray single crystal diffractometer . Five kinds of coordination forms were found . All atoms in the cell , including C and F , were properly located . In the process of study in a cordylite-(Ce ), a new mineral was discovered , whose chemical formula is (Ca0.5□0.5) BaCe2 (CO3)4F . It is isostructural with baiyuneboite - (Ce ), but different in composition (Na in baiyuneboite- (Ce ) is substituted by Ca disorderly ) . On the basis of the studies a proposal to re-define cordylite-(Ce )as a mineral group name is put forth by the authors . Finally a new type of twinning of huanghoite-(Ce ) was found on the systematical absence of diffraction data by means of a single crystal diffractometer . 展开更多
关键词 rare - earth mineral crystal structure cordylite -(Ce) cebaite - (Ce) baiyuneboite - (Ce) huanghoite - (Ce) X - ray analysis .
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Synthesis,structural characterization and solubility of 2-(1-substituted-1,11-undecylidene)-5-arylimino-△~3 -1,3,4-thiadiazolines
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作者 Shu Hui Jin Xiao Mei Liang Xu Yang Fu Heng Chen Dao Quan Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第11期1267-1270,共4页
A series of novel 2-(1-substituted-1,11-undecylidene)-5-arylimino-△^3-1,3,4-thiadiazolines (4) were synthesized and their structure was characterized by ^1H NMR, ^13C NMR and elemental analysis. Their solubility ... A series of novel 2-(1-substituted-1,11-undecylidene)-5-arylimino-△^3-1,3,4-thiadiazolines (4) were synthesized and their structure was characterized by ^1H NMR, ^13C NMR and elemental analysis. Their solubility in both polar and non-polar solvents is significantly improved owing to the introduction of ethyl or methylthio group at cyclododecyl ring as compared with parent compounds [1, 2-(1,11-undecylidene)-5-arylimino-△^3-1,3,4-thiadiazolines]. However, their fungicidal activity against Rhizoctonia solani is less than that of parent compounds. X-ray diffraction analysis of a representative compound (4d) showed that the conformation of 12-membered ring is still [3333], in which the ethyl group present at the side-exo position and the thiadiazoline ring at the comer carbon. The thiadiazoline plane is perpendicular to the cyclododecyl one. 展开更多
关键词 2-(1-Substituted-1 11-undecylidene)-5-arylimino-△^3-1 3 4-thiadiazoline SOLUBILITY Crystal structure SYNTHESIS
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Structural Basis for the Interaction of 14-3-3<i>β</i>with Tricarboxylic Acid Cycle Intermediate Malate
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作者 Zhiqiang Hou Lijing Su Xiaoyan Liu 《Journal of Biosciences and Medicines》 2017年第8期36-47,共12页
The protein family of 14-3-3(s) has risen to a position of higher importance as an adaptor protein in cell biology. The seven highly conserved human 14-3-3 proteins coordinate diverse cellular processes including apop... The protein family of 14-3-3(s) has risen to a position of higher importance as an adaptor protein in cell biology. The seven highly conserved human 14-3-3 proteins coordinate diverse cellular processes including apoptosis, DNA damage response, protein trafficking, and others. In liver hepatocytes, 14-3-3β binds to Ser196-phosphorilated glucose-responsive carbohydrate response element-binding protein (ChREBP) to inhibit converting excess carbohydrate to fat by regulating the nuclear/cytosol trafficking of ChREBP. Here, we report X-ray crystal structures of homodimeric mammalian 14-3-3β in its apo, Malate-bound forms. The determined apo structure was captured with one monomer in the closed state, whereas the other one had an open conformation. Strikingly, 14-3-3β binds Malate dynamically with a double-closed state, which is distinct from all previously characterized 14-3-3(s) and target ligand-binding modes. Malate docks into a first-time observed cofactor pocket located at the concaved interface of 14-3-3β helices α2, α3, α4 through mainly electrostatic and hydrogen interactions. Such a Tricarboxylic Acid Cycle intermediate Malate bond model might offer a new approach to further analyze insulin-independent 14-3-3/ChREBP pathway of de novo fat synthesis in the liver. 展开更多
关键词 Crystal structure 14-3-3 Protein CHREBP TRANSCRIPTION Activation MALATE Malic Acid
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Capital Structure and Natural Rate of Unemployment: An Empirical analysis
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作者 Liu hui 《International English Education Research》 2014年第10期47-50,共4页
The model based on Marxism economics such as capital structure ,capital deposit and capital cycles measure directly natural rate of the unemployment. The natural rate of unemployment is decided by the capital per work... The model based on Marxism economics such as capital structure ,capital deposit and capital cycles measure directly natural rate of the unemployment. The natural rate of unemployment is decided by the capital per worker, capital structure and average wage. According to the model the natural rate of the unemployment is empirical from 1991 to 2009.the result shows that the ascendant trend is very obvious. At last, according to the model, adjusting economic structure and regulating income distribution can reduce natural rate of unemployment. 展开更多
关键词 Natural rate of unemployment capital structure capital per worker
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Synthesis and Structural Characterization of [Co(Q)_2(H_2O)_2](Q=8-Hydroxyquinoline Ion)
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作者 胡长文 王春秀 +3 位作者 李晖 牛学丽 潘万龙 龚云 《Journal of Beijing Institute of Technology》 EI CAS 2006年第2期221-224,共4页
The single crystal of bi(8-hydroxyquinoline) bihydrated cobalt (Ⅱ) complex, [ Co(Q)2 (H2O2 ] (Q = 8-hydroxyquinoline ion), has been synthesized by general method and structurally characterized by single crys... The single crystal of bi(8-hydroxyquinoline) bihydrated cobalt (Ⅱ) complex, [ Co(Q)2 (H2O2 ] (Q = 8-hydroxyquinoline ion), has been synthesized by general method and structurally characterized by single crystal X-ray diffraction. Crystal data: C18H16CoN2O4, monoclinic, C2/c, α = 1.336 2(4) nm, b = 0.941 2(3) nm, c = 1.354 3(4) nm, β= 109.672(4)°, Z = 4. In the complex, Co( Ⅱ ) ion is six-coordinated, forming a distorted octahedron. H-bonding and π-π stacking interaction play a significant role to form and stabilize the three-dimensional structure. 展开更多
关键词 crystal structure π-π stacking hydrogen bonding Co( complex 8-HYDROXYQUINOLINE
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Structural Properties of Early-Type Galaxies from the SDSS DR2
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作者 Feng-Shan Liu Zu-Gan Deng +1 位作者 Hong Wu Xiao-Yang Xia 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第5期503-521,共19页
Two-dimensional bulge/disk light decomposition with GIM2D in both the r- and g-bands has been applied to a sample of 129 early-type galaxies brighter than 13.5 magnitude in the r-band, selected from the Sloan Digital ... Two-dimensional bulge/disk light decomposition with GIM2D in both the r- and g-bands has been applied to a sample of 129 early-type galaxies brighter than 13.5 magnitude in the r-band, selected from the Sloan Digital Sky Survey Data Release 2. Intensity-weighted Fourier coefficient (α4/α) was also derived for each sample galaxy. Our analysis shows that there are correlations between bulge-to-total light ratio (B/T) with bulge Sersic index nB and between bulge and disk scale sizes. Isophotal shape parameter (α4/α) is not correlated with BIT and riB. Both bulge and disk components satisfy a color-magnitude relation. The space Fundamental Plane analysis shows that galaxies with larger B/T tend to lie tighter and closer to the line of k1 + k2 = 8 (the so-called "zone of avoidance") than the galaxies with smaller B/T. It indicates that existence of the disk component may lead to scatter of the distribution on the Fundamental Plane. Our analysis also shows that k1 + k2 correlates with (g-r) color and B/T, but does not correlate with (α4/α) for early-type galaxies. The fitted parameters and other retrieved parameters used in this paper for all sample galaxies are available online. 展开更多
关键词 galaxies elliptical and lenticular cD -galaxies photometry -galaxies structure - galaxies
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Expression,Purification and Structural Characterization of Mouse Talin-1 Head Δ139-168
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作者 Sun Xing-sheng Du Jia-yang Liu Jia-fu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2020年第2期108-115,共8页
Talin-1 head(hereinafter referred to as TH)is the head structure of talin protein,which contains a four-point-one-protein/ezrin/radixin/moesin(FERM)domain.Its F1 domain contains an unstructured loop of 30 amino acids(... Talin-1 head(hereinafter referred to as TH)is the head structure of talin protein,which contains a four-point-one-protein/ezrin/radixin/moesin(FERM)domain.Its F1 domain contains an unstructured loop of 30 amino acids(139-168),which does not interact with other domains.Because TH doesn’t get the crystal structure and whether the unstructured loop has obvious influence on the TH secondary structure,therefore,the truncated talin-1 headΔ139-168(hereinafter referred to as THΔ)was constructed and its structure and the impact of stability after truncation were analyzed.Molecular biology and structural biology methods were used to construct prokaryotic expression vectors of TH and THΔ,explore and optimize the expression conditions of recombinants,and they were purified by affinity chromatography and FPLC gel filtration chromatography.Finally,a large number of stable,high-purity protein samples were prepared successfully.The physicochemical properties and structural stability of the proteins were investigated by dynamic light scattering and circular dichroism.The results showed that the THΔsecondary structure of the truncated body did not change significantly,the structural stability was enhanced and the resistance to guanidine hydrochloride and high temperature was stronger. 展开更多
关键词 talin-1 head talin-1 headΔ139-168 circular dichroism(CD) secondary structure stability
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From Quantitative Issues to Structural Ones: An Interpretation of China's Labor Market 被引量:9
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作者 蔡昉 《China Economist》 2016年第1期92-111,共20页
Based on the latest demographic and labor data, this paper reveals the changes in China's labor supply and demonstrates that China's key employment issues are no longer quantitative contradictions but increasingly h... Based on the latest demographic and labor data, this paper reveals the changes in China's labor supply and demonstrates that China's key employment issues are no longer quantitative contradictions but increasingly have become structural issues related to labor market mismatch. Due to real and potential economic growth rates being consistent, cyclical unemployment is, at least for now, not striking. If traditional policy measures continue to be followed in disregard of frictional and structural attributes of the labor market to increase total employment, not only will China's employment issues persist but new labor market problems may arise as well China should focus on addressing structural unemployment contradictions. 展开更多
关键词 cyclical unemployment frictional unemployment structural unemployment quantitative issues of employment structural issues of unemployment
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Prediction of Protein OmpH in Structure of C47-8 Pasteurella multocida
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作者 繁萍 张瑞强 +3 位作者 张卫 丰琳琅 陈忍霞 赵静 《Agricultural Science & Technology》 CAS 2012年第6期1186-1189,1206,共5页
[Objective] This study aimed to predict the structure of protein OmpH from Pasteurella multocida C47-8 (PmC47-8) strain of yak. [Method] Online BLAST, signal peptide prediction, secondary structure prediction and pr... [Objective] This study aimed to predict the structure of protein OmpH from Pasteurella multocida C47-8 (PmC47-8) strain of yak. [Method] Online BLAST, signal peptide prediction, secondary structure prediction and protein characteristics of sequencing result of gene OmpH from PmC47-8 strain were analyzed. [Result] The similarities of gene OmpH from PmC47-8 with the published 81 OmpH genes were between 84% and 99%; a signal peptide was found with the cleavage sites between 20 and 21 in the polypeptide; secondary structure prediction showed that folding structure accounted for 49.8% and loop structure for 50.2%; it predicted that there were 7 O-glycosylation sites in OmpH protein with the amino acid residual sites of 2, 45, 48, 330, 716, 721, 723, respectively, and 2 N-glycosylation sites with the amino acid residual sites of 15 and 35. [Conclusion] This study lays the foundation for the study on the immunity of OmpH gene from yak. 展开更多
关键词 PmC47-8 strain OmpH protein structure PREDICTION
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Periodic oscillation and fine structure of wedge-induced oblique detonation waves 被引量:11
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作者 Ming-Yue Gui Bao-Chun Fan Gang Dong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第6期922-928,共7页
An oblique detonation wave for a Mach 7 inlet flow over a long enough wedge of 30 turning angle is simulated numerically using Euler equation and one-step rection model.The fifth-order WENO scheme is adopted to captur... An oblique detonation wave for a Mach 7 inlet flow over a long enough wedge of 30 turning angle is simulated numerically using Euler equation and one-step rection model.The fifth-order WENO scheme is adopted to capture the shock wave.The numerical results show that with the compression of the wedge wall the detonation wave front structure is divided into three sections:the ZND model-like strcuture,single-sided triple point structure and dual-headed triple point strucuture.The first structure is the smooth straight,and the second has the characteristic of the triple points propagating dowanstream only with the same velocity,while the dual-headed triple point structure is very complicated.The detonation waves facing upstream and downstream propagate with different velocities,in which the periodic collisions of the triple points cause the oscillation of the detonation wave front.This oscillation process has temporal and spatial periodicity.In addition,the triple point trace are recorded to obtain different cell structures in three sections. 展开更多
关键词 Oblique detonation wave Wedge - Periodic oscillation Fine structure
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Continental- Margin Structure of Northeast China and Its Adjacent Areas 被引量:11
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作者 Tang Kedong, Shenyang Institute of Geology and Mineral Resources, Shenyang,Liaoning ProvinceWang Ying,Bureau of Geology and Mineral Resources of Heilongjiang Province,Harbin, HeilingjiangHe Guoqi and Shao Ji’an Peking U niversity, Beijing Liu Xinzhu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1995年第3期241-258,共18页
The continental margin of Northeast China and its adjacent areas is composed of two tectonic belts. The inner belt is a collage made up of fragments resulting from breakup of an old land with the north part related to... The continental margin of Northeast China and its adjacent areas is composed of two tectonic belts. The inner belt is a collage made up of fragments resulting from breakup of an old land with the north part related to the evolution of the Palaeo-Asian Ocean and the south part to the evolution of the Palaeo - Pacific Ocean. The outer belt is a Mesozoic terrane, which is a melange made up of fragments of the Late Palaeozoic to Early Mesozoic oceanic crust and the Late M esozoic trench accumulations.There existed another ocean-the Palaeo - Pacific Ocean during the period from the closing of the Palaeo-Asian Ocean to the opening of the modern Pacific Ocean or from the Devonian to Jurassic, and the ocean-floor spreading of the Palaeo - Pacific Ocean led to the formation of the above-mentioned tectonic belts. The development of the strike-slip fault system after the Late Jurassic and the formation of an epicontinental volcano -plutonic rock belt in the Late Cretaceous to Early Tertiary are attributed to the interaction between the modern Pacific plate and the Eurasian plate. 展开更多
关键词 continental-margin structure Bohai Sea block Mesozoic terrane non- subducted ocean crust Palaeo - Pacific Ocean
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