期刊文献+
共找到10,015篇文章
< 1 2 250 >
每页显示 20 50 100
Electrical structure identification of deep shale gas reservoir in complex structural area using wide field electromagnetic method
1
作者 Gu Zhi-Wen Li Yue-Gang +6 位作者 Yu Chang-Heng Zou Zhong-Ping Hu Ai-Guo Yin Xue-Bo Wang Qinag Ye Heng Tan Zhang-Kun 《Applied Geophysics》 SCIE CSCD 2024年第3期564-578,619,620,共17页
To fully exploit the technical advantages of the large-depth and high-precision artificial source electromagnetic method in the complex structure area of southern Sichuan and compensate for the shortcomings of the con... To fully exploit the technical advantages of the large-depth and high-precision artificial source electromagnetic method in the complex structure area of southern Sichuan and compensate for the shortcomings of the conventional electromagnetic method in exploration depth,precision,and accuracy,the large-depth and high-precision wide field electromagnetic method is applied to the complex structure test area of the Luochang syncline and Yuhe nose anticline in the southern Sichuan.The advantages of the wide field electromagnetic method in detecting deep,low-resistivity thin layers are demonstrated.First,on the basis of the analysis of physical property data,a geological–geoelectric model is established in the test area,and the wide field electromagnetic method is numerically simulated to analyze and evaluate the response characteristics of deep thin shale gas layers on wide field electromagnetic curves.Second,a wide field electromagnetic test is conducted in the complex structure area of southern Sichuan.After data processing and inversion imaging,apparent resistivity logging data are used for calibration to develop an apparent resistivity interpretation model suitable for the test area.On the basis of the results,the characteristics of the electrical structure change in the shallow longitudinal formation of 6 km are implemented,and the transverse electrical distribution characteristics of the deep shale gas layer are delineated.In the prediction area near the well,the subsequent data verification shows that the apparent resistivity obtained using the inversion of the wide field electromagnetic method is consistent with the trend of apparent resistivity revealed by logging,which proves that this method can effectively identify the weak response characteristics of deep shale gas formations in complex structural areas.This experiment,it is shown shows that the wide field electromagnetic method with a large depth and high precision can effectively characterize the electrical characteristics of deep,low-resistivity thin layers in complex structural areas,and a new set of low-cost evaluation technologies for shale gas target layers based on the wide field electromagnetic method is explored. 展开更多
关键词 complex tectonic area in southern Sichuan wide field electromagnetic method deep exploration shale gas reservoir electrical structure
下载PDF
Discussion on the Complex Structure of Nilpotent Lie Groups Gk
2
作者 Caiyu Du Yu Wang 《Open Journal of Applied Sciences》 2024年第6期1401-1411,共11页
Consider the real, simply-connected, connected, s-step nilpotent Lie group G endowed with a left-invariant, integrable almost complex structure J, which is nilpotent. Consider the simply-connected, connected nilpotent... Consider the real, simply-connected, connected, s-step nilpotent Lie group G endowed with a left-invariant, integrable almost complex structure J, which is nilpotent. Consider the simply-connected, connected nilpotent Lie group Gk, defined by the nilpotent Lie algebra g/ak, where g is the Lie algebra of G, and ak is an ideal of g. Then, J gives rise to an almost complex structure Jk on Gk. The main conclusion obtained is as follows: if the almost complex structure J of a nilpotent Lie group G is nilpotent, then J can give rise to a left-invariant integrable almost complex structure Jk on the nilpotent Lie group Gk, and Jk is also nilpotent. 展开更多
关键词 Almost complex structure Nilpotent Lie Group Nilpotent Lie Algebra
下载PDF
Tree species identity and interaction determine vertical forest structure in young planted forests measured by terrestrial laser scanning
3
作者 Mengxi Wang Lander Baeten +7 位作者 Frieke Van Coillie Kim Calders Kris Verheyen Quentin Ponette Haben Blondeel Bart Muys John Armston Hans Verbeeck 《Forest Ecosystems》 SCIE CSCD 2024年第3期266-275,共10页
Vertical forest structure is closely linked to multiple ecosystem characteristics,such as biodiversity,habitat,and productivity.Mixing tree species in planted forests has the potential to create diverse vertical fores... Vertical forest structure is closely linked to multiple ecosystem characteristics,such as biodiversity,habitat,and productivity.Mixing tree species in planted forests has the potential to create diverse vertical forest structures due to the different physiological and morphological traits of the composing tree species.However,the relative importance of species richness,species identity and species interactions for the variation in vertical forest structure remains unclear,mainly because traditional forest inventories do not observe vertical stand structure in detail.Terrestrial laser scanning(TLS),however,allows to study vertical forest structure in an unprecedented way.Therefore,we used TLS single scan data from 126 plots across three experimental planted forests of a largescale tree diversity experiment in Belgium to study the drivers of vertical forest structure.These plots were 9–11years old young pure and mixed forests,characterized by four levels of tree species richness ranging from monocultures to four-species mixtures,across twenty composition levels.We generated vertical plant profiles from the TLS data and derived six stand structural variables.Linear mixed models were used to test the effect of species richness on structural variables.Employing a hierarchical diversity interaction modelling framework,we further assessed species identity effect and various species interaction effects on the six stand structural variables.Our results showed that species richness did not significantly influence most of the stand structure variables,except for canopy height and foliage height diversity.Species identity on the other hand exhibited a significant impact on vertical forest structure across all sites.Species interaction effects were observed to be site-dependent due to varying site conditions and species pools,and rapidly growing tree species tend to dominate these interactions.Overall,our results highlighted the importance of considering both species identity and interaction effects in choosing suitable species combinations for forest management practices aimed at enhancing vertical forest structure. 展开更多
关键词 TreeDivNet FORBIO Stand structural complexity Terrestrial laser scanning Vertical forest structure Tree diversity Planted forests
下载PDF
Syntheses,crystal structures,and quantum chemistry calculation of two Ni(Ⅱ)coordination polymers
4
作者 LI Xiumei HUANG Yanju +1 位作者 LIU Bo PAN Yaru 《无机化学学报》 SCIE CAS CSCD 北大核心 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
下载PDF
Synthesis,crystal structure and photo-physical properties of tris(4-methyl-2,5-diphenylpyridine)iridium for OLED
5
作者 FENG Yangyang XU Mingming +4 位作者 WANG Hongyou ZHU Yunyao LUO Yuan LEI Huaidong CHEN Honglai 《贵金属》 CAS 北大核心 2024年第3期28-32,共5页
Organic light-emitting diodes(OLEDs)have important applications in the field of next-generation displays and lighting,and phosphorescent iridium complexes are an important class of electroluminescent phosphorescent ma... Organic light-emitting diodes(OLEDs)have important applications in the field of next-generation displays and lighting,and phosphorescent iridium complexes are an important class of electroluminescent phosphorescent materials.In this paper,Ir(bmppy)_(3),tris(4-methyl-2,5-diphenylpyridine)iridium,was synthesized and elvaluted for photo-physical characteristics.Single crystals suitale for X-ray diffraction(XRD)were grown from a mixture solvent of dichloromethane and absolute ethanol.The composition and structur of Ir(bmppy)_(3)were determined by element analysis,NMR spectra and XRD.The complex crystallizes in the monoclinic symmetry with the space group P21/c with a slightly distorted octahedral configuration.As measured by UV-Visible and photoluminescence spectra,Ir(bmppy)_(3) displays a maximum emission at at 527 nm at ambient temperature,a typical green-emitting profile.The complex has potential for application in the OLED industry. 展开更多
关键词 OLED iridium complex phosphorescent material crystal structure photo-physical properties Ir(bmppy)_(3)
下载PDF
Input Structure Design for Structural Controllability of Complex Networks 被引量:1
6
作者 Lifu Wang Zhaofei Li +2 位作者 Guotao Zhao Ge Guo Zhi Kong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第7期1571-1581,共11页
This paper addresses the problem of the input design of large-scale complex networks.Two types of network components,redundant inaccessible strongly connected component(RISCC)and intermittent inaccessible strongly con... This paper addresses the problem of the input design of large-scale complex networks.Two types of network components,redundant inaccessible strongly connected component(RISCC)and intermittent inaccessible strongly connected component(IISCC)are defined,and a subnetwork called a driver network is developed.Based on these,an efficient method is proposed to find the minimum number of controlled nodes to achieve structural complete controllability of a network,in the case that each input can act on multiple state nodes.The range of the number of input nodes to achieve minimal control,and the configuration method(the connection between the input nodes and the controlled nodes)are presented.All possible input solutions can be obtained by this method.Moreover,we give an example and some experiments on real-world networks to illustrate the effectiveness of the method. 展开更多
关键词 complex network input configuration minimum controlled node set structural controllability
下载PDF
Auxiliary Software for Defining the Parameters of the Structural Organization of a Complex System
7
作者 Branislav M. Savic 《Journal of Software Engineering and Applications》 2024年第2期109-128,共20页
The developed auxiliary software serves to simplify, standardize and facilitate the software loading of the structural organization of a complex technological system, as well as its further manipulation within the pro... The developed auxiliary software serves to simplify, standardize and facilitate the software loading of the structural organization of a complex technological system, as well as its further manipulation within the process of solving the considered technological system. Its help can be especially useful in the case of a complex structural organization of a technological system with a large number of different functional elements grouped into several technological subsystems. This paper presents the results of its application for a special complex technological system related to the reference steam block for the combined production of heat and electricity. 展开更多
关键词 complex System structural Organization Auxiliary Software PARAMETERS
下载PDF
Supporting Skin Structure and Its Barrier Functions with Evidence-Based Skin Care Ingredients
8
作者 Marsha Tharakan Lori Lonczak 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第2期200-210,共11页
The epidermis, and in particular its outermost layer, the stratum corneum, contributes much of the barrier function of the skin and is a readily visible representation of skin health. Maintaining the health of the ski... The epidermis, and in particular its outermost layer, the stratum corneum, contributes much of the barrier function of the skin and is a readily visible representation of skin health. Maintaining the health of the skin barrier has arguably become more important than ever in the modern world, in which a large majority of people are exposed to environmental insults. These external factors can damage the integrity of the skin barrier and prematurely age the skin. Therefore, it has become increasingly important to maintain and protect the stratum corneum. Here, we briefly review the complex, multilayered structure of the skin and relate it to clinically translatable function, with an emphasis on the stratum corneum. In the context of epidermal structure and function, the formulation and clinical data for Phelityl® Reviving Cream will be reviewed. Phelityl Reviving Cream was shown to be associated with improvements in both immediate- and long-term parameters, including a significant positive effect on the skin barrier and immediate and long-lasting hydration. 展开更多
关键词 Skin structure Skin Barrier Stratum Corneum Phelityl Reviving Cream Phelityl complex
下载PDF
Generalized response displacement methods for seismic analysis of underground structures with complex cross section
9
作者 Xu Zigang Ding Linling +2 位作者 Du Xiuli Xu Chengshun Zhuang Haiyang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第4期979-993,共15页
The response displacement method(RDM)is recommended for the seismic analysis of underground structures in the transverse direction for many codes,including bases for design of structures-seismic actions for designing ... The response displacement method(RDM)is recommended for the seismic analysis of underground structures in the transverse direction for many codes,including bases for design of structures-seismic actions for designing geotechnical works(ISO 23469)and code for seismic design of urban rail transit structures(GB 50909-2014).However,there are some obvious limitations in the application of RDM.Springs and the shear stress of the soil could be approximately evaluated for the structures having a simple cross section,such as rectangular and circular structures.It is necessary to propose simplified seismic analysis methods for structures with complex cross sections.This paper refers to the idea of RDM and proposes three generalized response displacement methods(GRDM).In GRDM1,a part of the soil surrounding a structure is selected to generate a generalized underground structure with a rectangular cross section,and the same analysis model as RDM is applied to analyze the responses of the structure.In GRDM2,a hollow soil model without a generalized structure is used to compute the equivalent load caused by the relative displacement of the soil,and the soil-structure interaction model is applied to calculate the responses of the structure.In GRDM3,a continuous soil model is applied to compute the equivalent load caused by the relative displacement and shear stress of the soil,and the soil-structure interaction model is applied to analyze the responses of the structure,which is the same as the model used in GRDM2.The time-history analysis method(THAM)is used to evaluate the accuracy of the proposed simplified methods.Results show that the error of GRDM1 is about 20%,while the error is only 5%for GRDM2 and GRDM3.Among the three proposed methods,GRDM3 has obvious advantages regarding calculation efficiency and accuracy.Therefore,it is recommended to use GRDM3 for the seismic response analysis of underground structures that have conventional simple or complex cross sections. 展开更多
关键词 underground structures seismic analysis response displacement method equivalent seismic load complex cross section
下载PDF
Probing electronic structures of transition metal complexes using electron paramagnetic resonance spectroscopy
10
作者 Shengfa Ye 《Magnetic Resonance Letters》 2023年第1期43-60,I0003,共19页
Electron paramagnetic resonance(EPR)or electron spin resonance(ESR)has been widely employed to characterize transition metal complexes.However,because of the high degree of complexity of transition metal EPR spectra,h... Electron paramagnetic resonance(EPR)or electron spin resonance(ESR)has been widely employed to characterize transition metal complexes.However,because of the high degree of complexity of transition metal EPR spectra,how to extract the underlying electronicstructure information inevitably poses a major challenge to beginners,in particular for systems with S>1/2.In fact,the physical principles of transition metal EPR have long been well-established and since 1970s a series of dedicated voluminous monographs have been published already.Not surprisingly,they are not appropriate stating points for novices to grasp a panorama of the profound theory prior to scrutinizing in-depth references.The present review aims to fill this gap to provide a perspective of transition metal EPR and unveil some peculiar subtleties thereof on the basis of our recent work. 展开更多
关键词 EPR Electronic structures Transition metal complexes Spin Hamiltonian
下载PDF
Study of Suitability of Out-of-Codes Tall Slab-Column and Shearwall Structure 被引量:1
11
作者 GUO Nan ZHAO Tingting LIN Yiying 《沈阳建筑大学学报(自然科学版)》 CAS 北大核心 2012年第6期1014-1022,共9页
The purpose of this paper is to discuss the suitability of out-of-codes tall slab-column and shearwall structure and to popularize the structure in seismic region.In the research,flat-plate floor was used in slab-colu... The purpose of this paper is to discuss the suitability of out-of-codes tall slab-column and shearwall structure and to popularize the structure in seismic region.In the research,flat-plate floor was used in slab-column and shearwall structure in the practical engineering,the key parameters of slab-column and shearwall structure and frame-shearwall structure such as deflection,punching shear behavior,story drift and capability curve were worked out by static plastic analysis,elastic-plastic time history analysis and pushover analysis,then the suitability of out-of-codes tall slab-column and shearwall structure was evaluated.The results show that the out-of-codes tall slab-column and shearwall structure studies could satisfy the require of deflection and punching shear behavior,the story drift under 7 degree expected rare earthquake waves could satisfy the limit value in the codes and the seismic design spectrum was crossed by the capability curve of the structure and the structure could not collapse.The conclusion is that slab-column and shearwall structure with reasonable design built in Ⅱ soil site of intensity 7 seismic fortification zone can be designed higher than the limit height in the codes. 展开更多
关键词 slab-column and shearwall structure finite element analysis SUITABILITY out-of-codes
下载PDF
Synthesis and Crystal Structure of t he Complex of Antimony Trichloride and Dioxane 被引量:1
12
作者 臧祥生 陈娅如 +2 位作者 栾绍嵘 钟国清 郭应臣 《无机化学学报》 SCIE CAS CSCD 北大核心 2001年第6期901-904,共4页
New solid complex of the antimony trichloride and dioxane was obtained th rough a reaction of the dioxane and the absolute methanol solution of the antimony trichloride.The formula of the complex is[SbCl_(3)·{(CH... New solid complex of the antimony trichloride and dioxane was obtained th rough a reaction of the dioxane and the absolute methanol solution of the antimony trichloride.The formula of the complex is[SbCl_(3)·{(CH_(2))_(4)O_(2)}_(1.5)].The crystal structure of the comple x belongs to cubic system,space group I-43d,a=17.1417(5)?,Z=16.The trivalent antimony ion not only bonds directly to three chlorine anions,but also is co ordinated by three oxygen atoms of th e dioxane molecules.Two oxygen atoms in a dioxane molecule wi ll coordinate to different antimony ions,respectively. 展开更多
关键词 dioxane complex of antimony trichloride synthesis crystal structure
下载PDF
Theoretical Studies on Structures and Spectroscopic Properties of Highly Efficient Phosphorescent [Ru(terpy)(phen)X]+ Complexes
13
作者 金丽 张建坡 +1 位作者 张红星 白福全 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第4期391-398,I0003,共9页
The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine... The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine, phen=l,10-phenanthroline, and X=-C-=CH (1), X=Cl (2), X-CN (3)) were investigated theoretically using the density functional theory method. The ground and excited state geometries have been fully optimized at the B3LYP/LanL2DZ and UB3LYP/LanL2DZ levels, respectively. The absorption and emission spectra of the com- plexes in CHaCN solutions were calculated by time-dependent density functional theory with the PCM solvent model. The calculated bond lengths of Ru-C, Ru-N, and Ru-Cl in the ground state agree well with the corresponding experimental results. The highest occupied molecular orbital were dominantly localized on the Ru atom and monodentate X ligand for 1 and 2, Ru atom and terpy ligand for a, while the lowest unoccupied molecular orbital were π*(terpy) type orbital. Therefore, the lowest-energy absorptions of 1 and 2 at 688 and 631 nln are attributed to a dyz (Ru)+Tr/p(X)--π* (terpy) transition with MLCT/XLCT (metal-to-ligand charge transfer/X ligand to terpy ligand charge transfer) character, whereas that of 3 at 529 nm is related to a dyz (Ru)+π(terpy)-π* (terpy) transition with MLCT and ILCT transition character. The calculated phosphorescence of three complexes at 1011 nm (1), 913 nm (2), and 838 nm (3) have similar transition properties to that of the lowest-lying absorption. It is shown that the lowest lying absorptions and emissions transition character of these Ru(II) complexes can be tuned by changing the electron-withdrawing ability of the monodentate ligand. 展开更多
关键词 Mixed-ligand Ru(II) complexes Electronic structure Spectroscopic property DFT calculation UB3LYP method
下载PDF
Hydrothermal Synthesis and Crystal Structure of a Zinc Complex:[Zn_(2.5)(phen)(BDC)_2(OH)] (phen = 1,10-Phenanthroline, BDC = Benzene-1,4-dicarboxylic Acid) 被引量:10
14
作者 王庆伟 李秀梅 史林芳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第1期11-14,共4页
A metal-organic coordination polymer [ZnE.s(phen)(BDC)2(OH)]2 (phen = 1,10- phenanthroline, BDC = benzene-1,4-dicarboxylic acid) 1 has been hydrothermally synthesized and structurally characterized by single-c... A metal-organic coordination polymer [ZnE.s(phen)(BDC)2(OH)]2 (phen = 1,10- phenanthroline, BDC = benzene-1,4-dicarboxylic acid) 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analyses and IR spectroscopy. The complex crystallizes in the triclinic system, space group PI with a = 11.199(2), b = 11.593(2), c = 11.865(3)/A, α= 99.330(1), β = 111.506(1), γ = 104.804(1)^o, V= 1328.4(5)A^3, Dc= 1.722 g/cm^3, Z = 1, Mr = 1377.82, F(000) = 692,μ(MoKa) = 2.306 mm^-1, S = 1.093, R= 0.0281 and wR = 0.0756 for 4179 observed reflections (I 〉 2σ(/)). The coordination polyhedron around Zn(II) can be described as a tetrahedron, trigonal bipyramid and octahedron. It is worth noting that the crystal structure of 1 is composed of tetranuclear zinc clusters linked by {ZnO6} units. 展开更多
关键词 zinc complex hydrothermal synthesis crystal structure tetranuclear zinc cluster
下载PDF
Synthesis,Crystal Structure,and Spectral Properties of a Novel Co(II) Complex Containing Imidazole Derivative 被引量:8
15
作者 JIN Feng HAO Fu-Ying +2 位作者 MA Ji-Long WU Jie-Ying TIAN Yu-Peng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第11期1303-1308,共6页
A novel imidazole derivative with functional group and π-conjugated system, 1- [trans-4-(4-diethylaminostyryl)phenyl]imidazole (abbreviated as L), and its Con complex (COCl2L4)2 (Co2C168H184N24Cl4, Mr = 2799.... A novel imidazole derivative with functional group and π-conjugated system, 1- [trans-4-(4-diethylaminostyryl)phenyl]imidazole (abbreviated as L), and its Con complex (COCl2L4)2 (Co2C168H184N24Cl4, Mr = 2799.05 ) have been synthesized and the crystal structure of the latter was determined by X-ray diffraction. The crystal is of triclinic, space group PI with a = 8.823(3), b = 18.799(7), c =23.065(9) A, α = 77.349(6), β = 83.128(7), ), γ= 80.942(3)°, V = 3671.5(12) A^3, Z = 1, Dc = 1.266 g/cm^3,/z = 0.361 mm^-1 F(000) = 1482, the final R = 0.0587 and wR = 0.1284 for 6562 observed reflections with I 〉 2σ(I). In the molecular structure of (COCl2L4)2, there are two crystallographically unique units. The Co^Ⅱ atoms are six-coordinated by four N atoms from four imidazole ligands (L) and two Cl atoms to form a distorted octahedral geometry. The optical properties of complex (COCl2L4)2 have been experimentally studied. 展开更多
关键词 imidazole derivative n-conjugated system Co complex crystal structure optical property
下载PDF
Synthesis and Crystal Structure of Zinc(II) Complex with Isonicotinate Containing a Three-dimensional Hydrogen-bond Network 被引量:8
16
作者 沈良 刘加庚 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第4期253-255,共3页
A zinc complex, [Zn(iso)_2(H_2O)_4](iso=C_6H_4NO_2^-), was synthesized and characterized by elemental analysis, thermal analysis and IR spectrum studies. The crystal structure of the complex was determined by X-ray di... A zinc complex, [Zn(iso)_2(H_2O)_4](iso=C_6H_4NO_2^-), was synthesized and characterized by elemental analysis, thermal analysis and IR spectrum studies. The crystal structure of the complex was determined by X-ray diffraction. The crystal crystallizes in the triclinic system, molecular formula ZnC12H16N2O8, Mr=381.64, space group P with a = 6.338(1), b =6.919(1), c=9.277(1), α=96.28(1), β=104.91(1), γ=112.85(1)°, V=352.12(9)?3, Z=1, Dc=1.80g?cm-3 and F(000)=196, μ =1.791mm-1. The crystal structure was solved by direct methods for final R=0.0204 and Rw=0.0542 for 1258 observed reflections with [Fo>4σ(Fo)]. The crystal structure reveals that zinc ion is trans-octahedral with two pyridyl nitrogens and two aque oxygens at the equational positions and two aqua oxygens at the axial positions. The complex forms a three-dimensional network through intermolecular hydrogen bonds. 展开更多
关键词 ISONICOTINATE zinc complex crystal structure H-bonded network
下载PDF
Synthesis, Crystal Structure and Antimicrobial Activity of a Novel Ni(II) Complex 被引量:5
17
作者 胡喜兰 许兴友 +1 位作者 尹福军 王大奇 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第6期733-737,共5页
A new nickel(Ⅱ) complex, C34H38N8NiO4, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group P21/c with a = 11.715(5), b = 12.328(5), c =11.113... A new nickel(Ⅱ) complex, C34H38N8NiO4, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group P21/c with a = 11.715(5), b = 12.328(5), c =11.113(5)A, β= 92.589(5)°, Z = 2, Dc = 1.411 g/cm^3,μ = 0.658 mml, the final R = 0.0427 and wR = 0.1099 for 2229 observed reflections with I 〉 2σ(I). The complex is a centrosymmetric plane in which nickel(Ⅱ) is coordinated in a regular octahedron to the ligand phenytoin through the nitrogen atoms of ethylenediamine, imine and amine. The complex was valued for its antimicrobial activity against bacterial strands using the agar diffusion method, and found to be active against the four test bacterial organisms. Preliminary screening for antimicrobial activities showed that the title complex is quite active against standard strains of Salmonella species, Staphylococcus aureus, Bacillus pumilus and Eschierichia coli. 展开更多
关键词 NICKEL complex SYNTHESIS crystal structure antimierobial activity
下载PDF
Syntheses,Crystal Structures and Antibacterial Activities of Complexes [(C_9H_(18)NS_2)_3M(Ⅲ)](M = Sb and Bi) 被引量:7
18
作者 孙汝中 郭应臣 +2 位作者 柳文敏 陈书阳 冯玉全 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第5期655-660,共6页
Two novel complexes,[(C9H18NS2)3Sb(III)](1) and [(C9H18NS2)3Bi(III)](2),were synthesized and characterized by elemental analysis,IR,TG and X-ray single-crystal diffraction.Both 1 and 2 crystallize in the m... Two novel complexes,[(C9H18NS2)3Sb(III)](1) and [(C9H18NS2)3Bi(III)](2),were synthesized and characterized by elemental analysis,IR,TG and X-ray single-crystal diffraction.Both 1 and 2 crystallize in the monoclinic system,P21/c space group.The data for 1:a = 1.6964(3),b = 1.02149(17),c = 2.5650(3) nm,β = 121.824(8)°,Z = 4,V = 3.7766(10) nm^3,Dc = 1.293 g·cm^-3,F(000) = 1536,μ = 1.082 mm^-1,the final R = 0.0500,wR = 0.1562 and S =1.072.The data for 2:a = 1.6802(9),b = 1.0256(6),c = 2.5083(10) nm,β = 121.77(3)°,Z = 4,V = 3.675(3) nm^3,Dc = 1.486 g·cm^-3,F(000) = 1664,μ = 5.159 mm^-1,the final R = 0.0481,wR = 0.1055 and S =1.076.The coordinated geometry of the central M(III) with six sulfur atoms from three ligands is a distorted pentagonal pyramid configuration.The dimer structural system is formed by the weak interactions of M…S and C-H…S between two molecules.The complexes were valued for their antibacterial activities by agar-streak method.It was found that 1 is active against the four test bacterial organisms. 展开更多
关键词 sodium dibutyl dithiocarbamate antimony(III) complex bismuth(III) complex crystal structure antibacterial activity
下载PDF
Hydrothermal Synthesis and Crystal Structure of a New Zero-dimensional Complex: [Zn(H_2BPTC)(phen)_2]_n·3nH_2O 被引量:9
19
作者 李秀梅 董艳辉 +2 位作者 王庆伟 崔运成 刘博 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第12期1495-1498,共4页
A new metal-organic coordination complex [Zn(H2BPTC)(phen)2]n.3nH2O (BPTC = 3,3',4,4'-benzophenone tetracarboxylate, phen = 1,10-phenanthroline) 1 has been obtained from hydrothermal reaction and characterized... A new metal-organic coordination complex [Zn(H2BPTC)(phen)2]n.3nH2O (BPTC = 3,3',4,4'-benzophenone tetracarboxylate, phen = 1,10-phenanthroline) 1 has been obtained from hydrothermal reaction and characterized by elementaj analysis, IR, TG and single-crystal X-ray diffraction. In compound 1, the zinc cation is hexa-coordinated with two carboxylate oxygen atoms from one H2BPTC ligand and four nitrogen atoms from two different phen ligands, showing a slightly distorted octahedral geometry. Crystal data: C41H30N4O12Zn, Mr = 836.06, monoclinic, P21/c, a = 14.2714(9), b = 16.9386(10), c = 15.0151(9)A, β = 101.3420(10)^o, V= 3558.8(4)A3 Dc = 1.560 g/cm^3,μ(MoKa) = 0.766 mm^-1, F(000) = 1720, Z= 4, R = 0.0439 and wR = 0.1157 for 4123 observed reflections with I 〉 2 o(I). 展开更多
关键词 3 3' 4 4'-benzophenone tetracarboxylate crystal structure zinc(Ⅱ) complex
下载PDF
Investigation on the syntheses and structures of Y^(Ⅲ) complexes with ami-nopolycarboxylic acids (Ⅳ) 被引量:3
20
作者 WANG Jun, ZHANG Xiangdong, LING Xiao, JIA Weiguo, and FAN DaminDepartment of Chemistry, Liaoning University, Shenyang, 110036, China 《Rare Metals》 SCIE EI CAS CSCD 2002年第2期106-112,共7页
This paper deals with the structure of the Y^iii complex withaminopolycarboxylic acids, synthesis and struc- tural determinationof the complex (NH_4)[Y^III(edta)(H_2O)_3] ·3 H_2O (edta =ethylenediaminetetraacetic... This paper deals with the structure of the Y^iii complex withaminopolycarboxylic acids, synthesis and struc- tural determinationof the complex (NH_4)[Y^III(edta)(H_2O)_3] ·3 H_2O (edta =ethylenediaminetetraacetic acid). The crystal and molecularstructures of the (NH_4)[Y^III(edta)(H_2O)_3] ·3 H_2O complex havebeen determined by single-crystal X-ray structure analysis. Thecrystal of the complex (NH_4)[Y^III(edta)(H_2O)_3] ·3 H_2O belongsto orthorhombic crystal system and fdd2 space group. 展开更多
关键词 Y^III aminopolycarboxylic acids complex structure
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部