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Synthesis and Structural Characterization of a Salt {[Co(Phen)_3][Mo_2S_2(μ-S)_2(edt)_2]}_2·(DMSO)_2·(Et_2O)(Phen = 1,10-Phenanthroline, edt=Ethane-1,2-dithiolate)

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Chinese Journal of Structural Chemistry 2005年第7期24卷 773-778,736页

作者： ZHANgWen-Hua RENZhi-gang zhangyong SchoolofChemistryandChemicalEngineering SuzhouUniversit） Suzhou215006 China

Reaction of [Et4N]2[Mo2S2(μ-S)2(edt)2] with CoCl2?6H2O and Phen in MeCN followed by recrystallization in DMSO/Et2O gave rise to dark-red block crystals of {[Co(Phen)3]- [Mo2S2(μ-S)2(edt)2]}2?(DMSO)2?(Et2O) 1 (C88H86Co2Mo4N12O3S18). 1 crystallizes in the monoclinic system, space group P21/c with a = 24.631(4), b = 16.117(3), c = 24.791(4) ?, β = 92.835o, V = 9829.3(3) ?3, Z = 4, Mr = 2438.57, Dc = 1.648 g/cm3, F(000) = 4928, μ = 12.61 cm-1, R = 0.0936 and wR = 0.1682 for 12998 observed reflections with I > 2.0σ(I). In the structure of 1, the Co atom of the [Co(Phen)3]2+ dication is octahedrally coordinated by three Phen ligands. The Mo atom of the [Mo2S2(μ-S)2(edt)2]2- dianion is coordinated by two μ-S, one terminal S and two S atoms from edt, forming a distorted square pyramidal geometry. The mean Co–N and Mo…Mo bond distances are 2.139 and 2.872 ?, respectively.

关键词： molybdenum cluster sulfur cobalt crystal structure synthesis

TWO-DIMENSIONAL MODEL OF TRAFFIC FLOW CONTAININg ROAD SECTIONS

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Journal of Hydrodynamics 2004年第1期16卷 45-51页

作者： gUguo-qing ZHANgWei QIANXin-jian zhangyong SchoolofInformationScienceandTechnology EastChinaNormalUniversityShanghai200062China InstituteofSystemsScience UniversityofShanghaiforScienceandTechnologyShanghai200093China

Both the cross and road section are basic components in traffic systems. Ageneral cellular automaton model of two-dimensional traffic flow containing road section wasestablished. The model was simulated with respect to various section lengths and the randomdistribution of section lengths. The effect of road sections on the performance of traffic flow wasdiscussed based on simulation results

关键词： traffic flow model cellular automaton traffic simulation

Two-step measurement update for extended Kalman filtering

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Journal of Systems Engineering and Electronics 2005年第1期16卷 21-25页

作者： zhangyong'an ZhouDi Duanguangren CenterforControlandguidance HarbinInstituteofTechnologyHarbin150001P.R.China

The nonlinear filtering for a class of discrete-time stochastic dynamic systems whose measurement equations contain linear (or universal linearizable) components and nonlinear components which are mutually statistical independent is investigated. A two-step measurement update is proposed for the filtering of the systems. The first-step update is a linear (or universal linearization) measurement correction which introduces an intermediate estimate, while the second-step nonlinear linearization update produces the final posterior estimate based on the first-step estimate. Since the first measurement correction is a linear or universal linearization update, it provides an accurate linearization reference point for the second nonlinear measurement update. Two simulation examples show superiority of the new estimation method.

关键词： universal linearization extended Kalman filter modified gain extended Kalman filter target tracking.

Effects of Anions and Cations on π-Complexation Between Olefin and Metal Halide

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Chemical Research in Chinese Universities 2005年第2期21卷 217-219页

作者： ZHOUJin-xia zhangyong-chun gUOXin-wen StateKeyLaboratoryofFineChemical DalianUniversityofTechnologyDalian116012P.R.China

An ab initio molecular orbital study was performed to determine the effects of anions and cations on the π-complexation of C_2H_4 on MX(M=Ag, Cu; X=F, Cl). The calculated results show the following order of adsorption strength: F ->Cl - for anions; Cu +>Ag + for cations. The results can be explained by the detailed analysis of atomic charge, orbital energy and orbital population by using the natural bond orbital(NBO) theory: (1) anions with stronger electronegativity can attract more electrons from the s orbital of M, while at the same time it does not obviously weaken the d orbital occupation of M, thus the nearly vacant s orbital and the sufficiently filled d orbitals of M help with forming σ-donation and d-π * backdonation with the π orbital and the π * orbital of olefin, respectively; (2) a smaller energy gap of symmetry-adapted orbitals between olefin and a cation can favor the electron transfer, that is why Cu + forms stronger adsorption with olefin than Ag + does.

关键词： Complexation ab initio Calculation Olefin Anion Cation

Stepping up after spinal cord injury:negotiating an obstacle during walking

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Neural Regeneration Research 2025年第7期20卷 1919-1929页

作者： Alain Frigon Charly g.Lecomte Department of Pharmacology-Physiology Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking consists of frequent voluntary modifications in the gait pattern to negotiate *** spinal cord injury,stepping over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including the parietal cortex,premotor cortex,and motor *** information and planning are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiology obstacle negotiation spinal cord injury

Synthesis and Crystal Structure of the Polymorphic Isomer [Cu(dafone)_2(H_2O)_2](Hphth)_2

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Chinese Journal of Structural Chemistry 2005年第7期24卷 831-835,739页

作者： HEXue-Yan LIUXun-gao LIBao-Long zhangyong KeyLaboratoryofOrganicSynthesisofJiangsuProvince CollegeofChemistryandChemicalEngineeringSuzhouUniversitySuzhou215006China

The polymorphic isomer [Cu(dafone)2(H2O)2](Hphth)2 1 (dafone = 4,5- diazafluoren-9-one, phth = 1,2-benzenedicarboxyl) has been synthesized and the structure was determined by single-crystal X-ray diffraction. Crystal data: C38H26CuN4O12, monoclinic, space group P21/a with a = 11.5863(18), b = 25.512(4), c = 11.878(2) ?, β = 111.696(3)o, V = 3262.1(9) ?3, Mr = 794.17, Z = 4, Dc = 1.617 g/cm3, F(000) = 1628, μ = 0.748 mm-1, R = 0.0603 and wR = 0.1132 for 6878 observed reflections with I > 2σ(I). 1 consists of one [Cu(dafone)2(H2O)2]2+ cation and two monoprotonated 1,2-benzenedicarboxyl (Hphth) anions and forms a two-dimensional hydrogen bond network via intermolecular hydrogen bond interactions between the coordinated water molecules and carboxylato-oxygen atoms from monoprotonated benzenedicarboxyl anions.

关键词： crystal structure polymorphism copper complex 4,5-diazafluoren-9-one benzenedicarboxyl

Synthesis and Structure Characterization of N-Phenyl-(2S)-hydroxy-3-[(2-hydroxybenzylidene)amino]propionamide

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Chinese Journal of Structural Chemistry 2005年第7期24卷 799-804,738页

作者： LIBin SHENZong-Xuan zhangyong ZHANgDe-Chun CollegeofChemistryandChemicalEngineering SuzhouUniversitySuzhou215006China

A new Schiff base, N-phenyl-(2S)-hydroxy-3-[(2-hydroxybenzylidene)amino]pro- pionamide, has been synthesized by using (S)-isoserine as the starting material. Its crystal struc- ture with solvent benzene was determined by X-ray single-crystal diffraction, elemental analysis and 1H NMR. The crystal belongs to the monoclinic system with space group P21, a = 5.673(3), b = 15.486(8), c = 18.753(9) ?, β = 90.086(7)o, C16H16O3N2?1/2C6H6, Mr = 323.36, V = 1647.7(14) ?3, Z = 4, Dc = 1.304 g/cm3, μ = 0.089 cm-1, F(000) = 684.00, the final R = 0.0624 and wR = 0.1320 for 2613 observed reflections (I > 2σ(I)). The asymmetric unit of the crystal has two crystallographically different molecules with the same configuration and one solvent benzene molecule, and they are not planar. In the crystal, molecules are stacked through H-bonds along [100] and the stacks are laterally interacted through H-bonds and extended along [010]. In the third direction [101], molecules interact through C–H…π interaction, which is one of the major factors stabilizing the crystal structure.

关键词： Schiff base synthesis crystal structure C–H…π interaction crystal growth

Temporal and spatial variations of the Huanghe River mouth bars

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Acta Oceanologica Sinica 2005年第2期24卷 43-56页

作者： YANgZuosheng zhangyong LIUZhan WEIHelong HEShufeng InstituteofEstuarineandCoastalStudies OceanUniversityofChinaQingdao266003China UniversityofPetroleum（EastChina） Dongying257061China InstituteofEstuarineandCoastalStudies OceanUniversityofChinaQingdao266003China／／QingdaoInstituteofMarineGeologyChinaGeologicalSurveyQingdao266071China QingdaoInstituteofMarinegeology ChinaGeologicalSurveyQingdao266071China

On the basis of the bathymetric records of 371 survey sections in the present Huanghe mouth area from 1996 to 2001, the temporal and spatial variations of the Huanghe mouth bars were studied by using gIS technology. The variation of the mouth bars is closely related to the water and sediment discharges from the Huanghe River to the sea that has been decreasing drastically in recent years, and to coastal hydrodynamic regimes. The characteristics of the mouth bars are unique in contrast with those of other estuaries in the world. (1) The mouth bars of the Huanghe River consist of many small sandbars. Usually the sandbars are of ellipse-shape with the long axis of about 1~6 km, and short axis of about 1~4 km. The long axis is parallel to the principal direction of tidal current, and the short axis is variable, depending on the local dynamics. The crest of the sandbars is only about 0.4 m below the water surface at low tide. They are distributed within an area of 20 km2, not far from the river mouth area. The present mouth bars are in small-medium size, quite different from the large one formed during the 1970s and 1980s, when the river sediment discharge was several times larger than that after 1996. (2) The scale of a river mouth bar is related to the river discharge of that year. In 1997 sediment discharge from the Huanghe River was 42 Mt, and the mouth bar consisted of several small scattered sandbars. In 1998 the size of mouth bars was much larger than that in 1997, as the sediment discharge from the Huanghe River increased to 363 Mt. Variation of the mouth bars largely depends on the sediment discharge with a correlation coefficient of 0.78. The calculation of the volume of the mouth bar area shows that about 30%~40% of the river's into-sea sediment is deposited in the mouth bar area. (3) Compared with other large estuaries in the world, the Huanghe mouth bars have three unique features in responding to its high sediment concentration: small size, steep slope gra

关键词： Huanghe mouth bars temporal and spatial variations mechanism of formation

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of geotechnical Structures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses significant risks to the stability of geotechnical structures *** understanding of the liquefaction triggering,and the post-failure large deformation behaviour is essential for designing resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading is described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A staggered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San Fernando *** agreement for liquefaction triggering and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)