• Issue 3,2011 Table of Contents
    Select All
    Display Type: |
    • Sedimentary Characters of the Wufeng Formation Upwelling Facies Source Rock in lower Yangtze area

      2011, 39(3).

      Abstract (757) HTML (34) PDF 0.00 Byte (714) Comment (0) Favorites

      Abstract:The Layered radiolarian cherty deposition of the latest Ordovician Wufeng Formation is one of the regional excellent hydrocarbon source rocks in the Lower Yangtze region and caused by the upwelling in the slope environment of the foreland flexural-break stagnation-flow basin margin. Under the control of the intensity and surging recurrence frequency of the upwelling,the Wufeng Formation is dominated by many siliceous rock/ siliceous shale couplets with different siliceous organisms and periodic variation in thickness.As the deposition under the anoxic environment, the Wufeng Formation mainly has high hydrocarbon potentional amorphous organic matters originated from algae and other pelagic organisms. In the impact from the upwelling, the different protection mechanisms of organic matter happen during the sedimentation of siliceous rock and siliceous shale, while organic carbon mainly relates to the adsorption protection of clay mineral and the loss of organic matter during the siliconoxide mineral transformation.

    • >土木工程与建筑学
    • An Improved Duncan-Chang Model Considering Effects of Intermediate Principal Stress and Shear Dilatancy

      2011, 39(3):309-313. DOI: 10.3969/j.issn.0253-374x.2011.03.001

      Abstract (1356) HTML (37) PDF 876.51 K (1046) Comment (0) Favorites

      Abstract:Duncan-Chang model is a nonlinear elastic model,which has been widely used in geotechnical engineering.For building on Mohr-Coulomb strength criterion and bulk strain assuming to be hyperbola in generalized Hooke’s law,Duncan-Chang model can not take the effects of intermediate principal stress and shear dilatancy into consideration.In order to reflect the effects of intermediate principal stress and shear dilatancy rationally,a new Duncan-Chang model is derived on the basis of unified strength theory and SHEN Zhujiang model.A novel parabolic bulk strain expression is adopted in the new model,and some forms of old parameter are improved.The modified model is validated with triaxial compression test results of coarse grained soil and clay.The results show that the new model can overcome the deficiency of the old Duncan-Chang model and reflect the effects of intermediate principal stress and shear dilatancy properly.

    • Numerical Simulation of Chloride Transportation Process in Unsaturated Concrete

      2011, 39(3):314-319. DOI: 10.3969/j.issn.0253-374x.2011.03.002

      Abstract (1058) HTML (10) PDF 1.12 M (1259) Comment (0) Favorites

      Abstract:In order to describe the chloride transportation process in unsaturated concrete components,the convection-diffusion equation of chloride was developed based on the mass conservation law.The parameters in the governing equation and the stabilization of FEM solution process were preliminary discussed.Based on the discussion,the influence of convection effect on chloride transportation process was analyzed quantitatively.The results show that the coupled effect of convection and diffusion will mainly occur in the surface layer of components,and the convection effect will be more obvious in the initial stage of transportation process.Finally,the results of the parameter sensitivity analysis of the numerical model show that the diffusion coefficient ratio between moisture and chloride will greatly affect the chloride transportation process.

    • Study on Rheological Test of Jinping Greenschist Under Step Load

      2011, 39(3):320-326. DOI: 10.3969/j.issn.0253-374x.2011.03.003

      Abstract (937) HTML (36) PDF 939.61 K (689) Comment (0) Favorites

      Abstract:Rock rheology tests were carried out on greenschist specimens from auxiliary tunnel of Jinping II Hydropower Station by step loading method. Phenomenon of the tests and the specimen axial and lateral stress-strain relationship as well as the flow obtained using the Burgers model varying parameters were analyzed. The results show that all samples’ strain on axial is greater than the lateral, while the rheology on lateral is larger than the axial,then the rheology and strain show an inconsistency. The rheological behaviours of all levels increase with the increasing of every stress levels. The axial rheology and lateral rheology of each level take the similar percentage of the total strain value on axial and lateral. Instantaneous deformation elastic model at all levels of each specimen is increasing,which complies with the general laws of rock rheology tests.Obvious anisotropy exists both in axial and lateral direction, and the phenomenon on the lateral can be more rapid and sensitive to reflect the rheological properties caused by the stress changes. The rheological parameter can reflect the greenschist rheological law, and the Burges Model can be a better simulation of the uniaxially rheological properties of Jinping greenschist.

    • Filtration of High-ordered Vibration Mode to Satisfy Explicit Method’s Stability

      2011, 39(3):327-332. DOI: 10.3969/j.issn.0253-374x.2011.03.004

      Abstract (947) HTML (34) PDF 904.58 K (596) Comment (0) Favorites

      Abstract:The consistency between transferring matrix’s characteristic vector and structure’s natural vibration shape was proved by taking central differential method as an example.The explicit method’s destabilization was caused by a combination of the transferring matrix’s characteristic value and the corresponding characteristic vector.A new method was proposed by filtrating the high destabilization vibration mode from result displacement vectors at different time,as a result,the wide time step size beyond the stability field will not lead to a calculation destabilization.With the proposed method,the calculation efficiency is improved with the same precision.Numerical model validates the method,which develops a new way to solve the stiff differential equations.

    • Research on Spatial Coherence of Stochastic Wind Field

      2011, 39(3):333-339. DOI: 10.3969/j.issn.0253-374x.2011.03.005

      Abstract (1203) HTML (37) PDF 1.30 M (1004) Comment (0) Favorites

      Abstract:This paper presents a phase-delay spectrum model to describe the spatial coherence of stochastic wind field,which can be used in large-scale stochastic wind field simulation.Coherence function is usually adopted to describe the spatial coherence in classic theory.It is found that coherence function is only second-order numerical characteristics and is far from describing the abundant probabilistic information of coherence of fluctuating wind speed.This study shows that Fourier phase-delay spectrum can give a comprehensive description of the coherence of fluctuating wind speed.Based on the analysis of primary factors affecting phase-delay,a basic model of phase-delay spectrum is presented.By a comparison with the measured phase-delay spectrum,the rationality and applicability of the model are verified.Finally,wind field simulation with this model obtains a good effect.

    • Experimental Study on Racking Performance of Light-frame Shear Walls with Various Sheathing Materials

      2011, 39(3):340-345. DOI: 10.3969/j.issn.0253-374x.2011.03.006

      Abstract (1305) HTML (36) PDF 2.41 M (968) Comment (0) Favorites

      Abstract:Monotonic experimental study on racking performance of ten light frame shear walls of 2.44 m×2.44 m with five different sheathing materials were conducted.The sheathing materials investigated was the imported OSB panels,domestic OSB panels,domestic plywood panel,magnesium board and gypsum board.Failure modes and load-displacement curves of shear walls with various sheathing materials are obtained and yield load,ultimate load,elastic stiffness and ductility of those shear walls were found through calculation and analysis.Test results show that comparing with shear wall with imported OSB panel,shear walls with domestic plywood and OSB panels improve the bearing capacity,ductility and energy dissipation a lot.Magnesium board is not only of good water and fire resistance but also better strength and toughness compared with gypsum board.Good mechanical properties of domestic sheathing make it applicable in the shear walls of light wood-frame house.

    • Test and Investigation on Dynamic Characteristics of Wood-frame Constructions

      2011, 39(3):346-352. DOI: 10.3969/j.issn.0253-374x.2011.03.007

      Abstract (1047) HTML (7) PDF 2.20 M (1169) Comment (0) Favorites

      Abstract:Field tests were performed on three wood-frame constructions in order to get their dynamic characteristics. Data obtained from the field tests, laboratory tests and literatures review were used to investigate the fundamental period and damping ratio of the wood-frame construction. Results show that gypsum board can not only dissipate the input earthquake energy but also increase structural stiffness. The damping ratio of wood-frame constructions is related to the amplitude of vibration, high damping ratio can be obtained depended on large amplitude vibration. The damping ratios of wood-framed construction obtained from earthquake records, shaking table tests, and forced vibration are close to or larger than 5% the value recommended in the code. And it is also confirmed that the earthquake coefficient of wood-frame constructions to be proposed to adopt the maximum value of the earthquake response spectrum curve in the Technical Specification of Wood-frame Construction is reasonable.

    • >交通运输工程
    • Influence of Embankment Thickness and Reinforcement on Cumulative Plastic Deformation of Soft Soil Foundation

      2011, 39(3):353-358. DOI: 10.3969/j.issn.0253-374x.2011.03.008

      Abstract (982) HTML (39) PDF 967.96 K (889) Comment (0) Favorites

      Abstract:Soft soil foundation under traffic loading was modelled by implicit dynamic finite element method (FEM).Based on numerical model,calculation and influential factor analysis of cumulative plastic deformation,a study was made of the influence of the thickness of embankment on cumulative plastic deformation induced by traffic loading.Then,from the standpoint of distribution of dynamic deviator stress of soil foundation underneath the center of loading area,an investigation was made into the meaning and mechanism that reinforcement could decrease cumulative plastic deformation of soil foundation.Analysis result shows that the cumulative plastic deformation of soil foundation with about 1 m thickness embankment develops rapidly under traffic loading.The cumulative plastic deformation decreases distinctly with the increasing of the thickness of embankment.As for soft soil foundation which is influenced significantly by traffic loading,geogrid reinforcement can improve vertical stress distribution,and decrease shear stress on the surface of soil foundation.The main reason of the decrease of cumulative plastic deformation of reinforced soil foundation is that reinforcement can diminish deviator stress on the upper part of it induced by traffic loading.

    • Variation of Aggregate Contacts Distribution in AC20 HMA Based on Digital Image Processing

      2011, 39(3):359-364. DOI: 10.3969/j.issn.0253-374x.2011.03.009

      Abstract (985) HTML (29) PDF 1.50 M (670) Comment (0) Favorites

      Abstract:In order to quantify the contacts between the aggregates,a new method based on digital image processing was put forward.For AC20 HMA,the amount of aggregates contacts and the features of the aggregates on all sample images acquired from 72 cut sections of rutting test samples were obtained through this method,and then the global contacts distribution rules of all aggregates,the local contacts distribution rules of each grades aggregates and the single particle contacts number distribution rules of each grades aggregates were acquired from statistical analysis.The variation of contacts amount on each images and influence factors including the content of aggregates above 2.36 mm (C>2.36),the fine index of aggregates above 2.36 mm (FI) and the segregation index(SI) were discussed.The internal relations of these three factors were as well analyzed.Contact features can be used for hot-mixture asphalt (HMA) gradation design as a referenced factor through these quantified analysis.

    • Research on Urban Road Network Mode Based on Queuing Theory

      2011, 39(3):365-369. DOI: 10.3969/j.issn.0253-374x.2011.03.010

      Abstract (1104) HTML (33) PDF 1008.50 K (850) Comment (0) Favorites

      Abstract:Based on the basic queuing theory in traffic engineering and the assumption that four kinds of road network modes under the same road land area ratio,a calculation was done on one vehicle’s total time-consuming changing trends along horizontal or vertical roads in four kinds of road network modes under the following two situations:keeping the same traffic arriving rate,changing road land area ratio;keeping the same road land area ratio,changing arriving rate.And then,total time-consuming and curves changing trends were compared and analyzed.Results show that low density and wide road network system (Mode 1) has some advantage in case of lower traffic arriving rate; When the traffic volume increases and leads to light congestion,the high density and one-way street network system (Mode 4) is the best.Key conclusions can directly guide road network planning.

    • Interactive Planning and Design of Land Use and Transportation in Rail Transit Station Area

      2011, 39(3):370-375. DOI: 10.3969/j.issn.0253-374x.2011.03.011

      Abstract (1027) HTML (48) PDF 1.84 M (820) Comment (0) Favorites

      Abstract:The paper presents a two-step interactive technology of station area land-use planning and transportation planning.Rail station passenger volume is first determined based on the land utilization;land-use planning is then adjusted according to the rail station capacity. The implementation procedure is proposed based on TransCAD. A case study of Big Hexi Pilot District in Changsha for regulatory optimization and traffic network construction validates the rationality and adaptability of the analysis model.

    • Reasonable Scale of Land Development Along Urban Rail Transit

      2011, 39(3):376-380. DOI: 10.3969/j.issn.0253-374x.2011.03.012

      Abstract (963) HTML (39) PDF 963.17 K (912) Comment (0) Favorites

      Abstract:An analysis of the current urban rail transit operation and its surrounding land-use planning reveals the fundmental cause of the dislocation between urban rail transit planning and land-use planning.A proposal is put forward that the maximum land development scale is subject to the transport capacity of urban rail transit line and the minimum should guarantee rail transit project financial balance on the premise of the given amount of government subsidies.The corresponding model founded on the basis of the proposed ideas is established and recomputed in a case study.The idea and model provide a feasible control method for determining the land-use scale along the urban rail transit lines.

    • Theoretical Study on Rail Corrugation on Curved Track of Metro Systems

      2011, 39(3):381-384. DOI: 10.3969/j.issn.0253-374x.2011.03.013

      Abstract (851) HTML (15) PDF 1.09 M (990) Comment (0) Favorites

      Abstract:Based on a detailed theoretical model of a single wheelset, a study is carried out on the relationship between rail corrugation on curved track in metro system with detailed analysis on possible factors contributing to stick-slip vibration considering flexible mode of wheelset, negative characteristics of creep force versus creepage and primary suspention.

    • Design and Evaluation of Emergency Path at Passenger Terminal of Expo 2010 Garden

      2011, 39(3):385-389. DOI: 10.3969/j.issn.0253-374x.2011.03.014

      Abstract (1115) HTML (34) PDF 2.11 M (1153) Comment (0) Favorites

      Abstract:Based on an analysis of the crowd behavior,the design method of passenger evacuation path and emergency evacuation routes in the passenger terminal landside of Expo 2010 Garden is proposed; the passenger evacuation simulation model of the most negative situation combined with the flow analysis of an passenger emergency evacuation of four kinds of scenarios of the passenger terminal is built; evacuation time as key evaluation index and the cumulative average density of the regional in the terminal as the secondary indicator are used to establish the evaluation methods and evaluation criteria for the passenger evacuation path of passenger terminal.Passenger organization program is optimized and adjusted by a simulation and analysis of L2/M2 Passenger Terminal of Expo Garden.Related research results enrich the domestic research theory of passenger emergency evacuation organization in passenger terminal.

    • >环境科学与工程
    • Composition and Spectroscopic Characteristics of Humic Substances in a Landfill

      2011, 39(3):390-394. DOI: 10.3969/j.issn.0253-374x.2011.03.015

      Abstract (952) HTML (21) PDF 939.05 K (908) Comment (0) Favorites

      Abstract:Humic acids(HA) and fulvic acids(FA)extracted from the aged refuse samples in Shanghai Laogang MSW Landfill site were characterized by elemental analysis,FTIR and 13C CP/MAS NMR.The results show that lignin and aromatic compounds,the major components of HA,are apparently more in HA than in FA.The proportion of alkyl-C in HA is also higher than that in FA.On the contrary,carboxylic acid groups are of large proportion in FA,and the oxy carbons related to cyclic polysaccharide are more in FA than those in HA.The degrees of aromatic condensation and stability of HA are higher than those of FA.On the other hand,with the increasing of the landfill age,the aromaticity and satability of HA increase while the content of oxygen-containing groups especially carboxylic acid in FA decreases.The degree of humification of both HA and FA increase with the increasing of landfill age.

    • Effect of Emergent Water Diversion on Diffusion of Pollutant in Northern Taihu Lake

      2011, 39(3):395-400. DOI: 10.3969/j.issn.0253-374x.2011.03.016

      Abstract (999) HTML (17) PDF 1.37 M (554) Comment (0) Favorites

      Abstract:Based on Delft3D model, a two-dimensional hydrodynamic model was established and validated against data of polluted water cluster in 2007 for Taihu Lake. Then hydrodynamic diffusion numerical experiments were performed to compare and analyze the diffusion of polluted water cluster under SE 3 m·s-1 wind condition with different water diversion measures. The simulated results show that the larger drawing flow from Wangyu River, the better effect on pollution diluted near Gonghu Waterworks in northern Taihu Lake, however larger draining flow to Taipu River has little influence there.As for geographic location and recharged water source, new water intake of Gonghu Waterworks is better than the old one.

    • Predictive Pipe Failure Models for Water Distribution System Based on Genetic Programming

      2011, 39(3):401-404. DOI: 10.3969/j.issn.0253-374x.2011.03.017

      Abstract (785) HTML (21) PDF 938.43 K (748) Comment (0) Favorites

      Abstract:The pipe failure data from 2004 to 2008 in a southern city were collected and average pipe age, tensile strength and pipe failure rate were obtained by data analysis, average pipe pressure was obtained by water distribution simulation. With the diameter classification of training samples, predictive pipe failure models which described the pipe failure rate correlations among diameters, average pipe pressure, average pipe age and tensile strength were established on the basis of the genetic programming. The feasibility and effectiveness of the models were verified by the pipe failure data from 2009. The results show that predictive pipe failure models can well describe actual conditions.

    • >机械、车辆与能源工程
    • Quantitative Study of Automotive Nonlinear Suspension System Based on Incremental Harmonic Balance Method

      2011, 39(3):405-410. DOI: 10.3969/j.issn.0253-374x.2011.03.018

      Abstract (1041) HTML (10) PDF 980.80 K (854) Comment (0) Favorites

      Abstract:Based on an analysis of nonlinear spring forces and damping forces for automotive suspension and tire,a nonlinear dynamic model of automobile heave vibration system with two degress of freedom (DOF) was built.Then,an incremental harmonic balance method (IHBM) was adopted to quantitatively study the system.The process of IHBM was derived,and the iterative process was studied.Meanwhile,the steady periodic solution of automobile nonlinear system was obtained with some harmonic numbers and stability of the periodic solution was studied as well.Based on the tracing calculation with the circular frequency of road excitation as parameter,the amplitude-frequency response characteristic of the system at the primary resonance was obtained.The numerical simulation of the approximate periodic solution by the IHBM was compared with the numerical method.Results show that the IHBM is an effective way to analyze both weak and strong nonlinear dynamics in engineering practice.

    • An Active Vehicle Transmission Device Reducing Torque Interruption

      2011, 39(3):411-415. DOI: 10.3969/j.issn.0253-374x.2011.03.019

      Abstract (1095) HTML (4) PDF 1.01 M (1052) Comment (0) Favorites

      Abstract:Torque interruption occurs during gear shifting of automated manual transmission (AMT). An active transmission device electrified manual transmission (eMT) is proposed for hybrid electric vehicle (HEV) application. Key technical characters of eMT are fixed axle gearboxes and parallel HEVs. Through integrated design of motor and transmission, eMT can fully coordinate the multiple power sources to meet the vehicle power demand. This technology makes use of the existing fixed axle transmission technology by overcoming the torque interrupting shortcomings.

    • Vertical Ride Quality of Flexible Car Body Railway Vehicles with Optimal Control

      2011, 39(3):416-420. DOI: 10.3969/j.issn.0253-374x.2011.03.020

      Abstract (1038) HTML (47) PDF 1.05 M (943) Comment (0) Favorites

      Abstract:A vertical dynamic model of railway passenger vehicle is built,which covers effects of car body flexibility and all vertical rigid modes.The model is simulated and researched by the control laws of railway vehicle secondary active suspension which are designed according to optimal control theory,based on track irregularity spectrum and time delay between axles.The results show that optimal control of preview based on track spectrum and time delay between axles is more effective than optimal control only based on track spectrum in the aspects of actuator output force and effects of car body vibration control; the acceleration transmissibility from track to flexible car body center can be reduced by optimal control,rigid and flexible vibration also can be controlled; low frequency vibration and the first order bending vibration of car body can be controlled effectively by optimal control simultaneously,but almost no effects on high frequency vibration,the response frequency range of actuator can be selected accordingly.

    • Shear Tension Fatigue Behavior of Bonded Joint,Weldbonded Joint and Spot-welded Joint

      2011, 39(3):421-426. DOI: 10.3969/j.issn.0253-374x.2011.03.021

      Abstract (996) HTML (5) PDF 2.02 M (1064) Comment (0) Favorites

      Abstract:A test was made on the fatigue life of structural bonded joints,weldbonded joints and spot-welded joints under different levels of stresses.Based on the hypothesis that load-life curve in single logarithm coordinate should be exponential curve,load-life curves of three kinds of joints were fitted by using of fatigue test data.Thus,fatigue performance of three kinds of joints was able to be described by these curves.And,a comparative analysis was made of the fatigure behavior of bonded joints,weldbonded joints.The study show that distribution of these fatigure test data follows a certain law.The fitted result proves that the hypothesis that load-life curve in single logarithm should be exponential curve is right.Fatigue strength of bonded joints is the highest of the three kinds of joints.On the contrary,fatigue strength of spot-welded is the lowest.Fatigue rupture behavior of weldbonded joint is more dangerous than that of bonded joint.Fatigue life of body joints can be improved by bonded process.These conclusions provide references for application of structural adhesive to vehicles.

    • >计算机与信息工程
    • Design of Activity Chain Behavioral Modes for Composite E-Service and Verification

      2011, 39(3):427-433. DOI: 10.3969/j.issn.0253-374x.2011.03.022

      Abstract (689) HTML (4) PDF 1.16 M (528) Comment (0) Favorites

      Abstract:The paper presents a novel concept of behavior specifications based on activity chain in which granularity is between activity and scenario.Four behavioral modes,such as chain existence mode,chain absence mode,chain precondition mode and chain response mode,are designed to express usual behavioral requirements based on activity chain and encoded on labeled transition system (LTS) with exact operation semantics.Compliance of composite E-service against activity chain modes is fitly defined to check whether composite E-services based on LTS correspond with activity chain modes.Finally,the paper presents the sufficient,necessary condition and algorithm for checking.

    • >海洋与地球科学
    • Original Preservation of Different Organic Micro-components in Muddy Source Rock

      2011, 39(3):434-439. DOI: 10.3969/j.issn.0253-374x.2011.03.023

      Abstract (2590) HTML (59) PDF 1.34 M (1058) Comment (0) Favorites

      Abstract:The muddy source rock is divided into many density fractions by density fractionation. The palynofacies analysis and the laser particles detection results show that the free organic particle with bio-texture is dominant in the fraction of ρ<1.6 g·cm3, which accumulates the majority of organic particles with well shape and large size in the source rock. The organic matter combines with the mineral tightly in the fractions of 1.6 g·cm-3<ρ<2.2 g·cm-3 and ρ>2.2 g·cm-3, which are rich in the particle amorphous and spongy amorphous organic mater respectively, indicating the amorphous organic matter is preserved by combining with the mineral (especial clay) in the source rock.The preservation ways of different organic micro-components are different in the source rock. A lot of amorphous exists in the fraction of the organic matter combine with the minerals, indicating this fraction is important in generating oil and gas of the source rock.

    • Sedimentary Characters of Wufeng Formation Upwelling Facies Source Rock in Lower Yangtze Area

      2011, 39(3):440-444. DOI: 10.3969/j.issn.0253-374x.2011.03.024

      Abstract (868) HTML (40) PDF 4.75 M (1166) Comment (0) Favorites

      Abstract:The layered radiolarian cherty deposition of the latest ordovician Wufeng Formation is one of the regional excellent hydrocarbon source rocks in the lower Yangtze region and caused by the upwelling in the slope environment of the foreland flexural-break stagnation-flow basin margin. Under the control of the intensity and surging recurrence frequency of the upwelling,the Wufeng Formation is dominated by many siliceous rock/ siliceous shale couplets with different siliceous organisms and periodic variation in thickness.As the deposition under the anoxic environment, the Wufeng Formation mainly has high hydrocarbon potentional amorphous organic matters originated from algae and other pelagic organisms. In the impact from the upwelling, the different protection mechanisms of organic matter happen during the sedimentation of siliceous rock and siliceous shale, while organic carbon mainly relates to the adsorption protection of clay mineral and the loss of organic matter during the siliconoxide mineral transformation.

    • Numerical Simulation of Collapsing and Sliding Response of Slope Triggered by Seismic Dynamic Action

      2011, 39(3):445-450. DOI: 10.3969/j.issn.0253-374x.2011.03.025

      Abstract (819) HTML (36) PDF 1.61 M (893) Comment (0) Favorites

      Abstract:A simulation was carried out on initial collapsing-sliding and a subsequent running out process of Wangjiayan Landslide in Beichuan County during the Wenchuan Earthquake triggered by single and combined action with time difference, regionality and spatial heterogeneity of primary and secondary seismic waves based on discrete element method by taking into the consideration the fact that vertical ground motion was still evident in post-earthquake field geological investigation, and formation mechanism and key controlling factors of slope collapsing and sliding under seismic load were determined,which was different with the traditional dynamic response analysis based on a consideration of horizontal seismic load. The result shows that initial collapsing and sliding of the slope are triggered by combined action of vertical and horizontal tension, which plays a dominant role,of primary seismic wave, whereas a subsequent collision and debris flow of slope mass fractured are triggered by combined action of primary and secondary seismic wave. On the other hand, single action of primary seismic wave is the key controlling factor inducing the slope initial collapsing and sliding, and the topography near the slope is the key controlling factor leading to collision and debris flow of the slope mass fractured in later process.

    • >数理科学与化学
    • Preparation and Structure Analysis of Antimony Trichloride and Bismuth Trichloride Comlexes with Valine

      2011, 39(3):451-455. DOI: 10.3969/j.issn.0253-374x.2011.03.026

      Abstract (872) HTML (46) PDF 1.01 M (623) Comment (0) Favorites

      Abstract:Two compounds of antimony trichloride and bismuth trichloride with valine are synthesized by solid phase synthesis at room temperature. Their compositions, determined by element analysis, are Sb(C5H10O2N)3·2H2O and Bi(C5H10O2N)2Cl·0.5H2O . The crystal structure of antimony complex with valine belongs to triclinic system and its lattice parameters are: a= 0.959 9 nm,b=1.506 8 nm, c=1.985 1 nm,α=92.27°,β=95.05°,γ=104.27°. The crystal structure of bismuth complex with valine belongs to monoclinic system and its lattice parameters are: a=1.601 2 nm, b=1.894 1 nm, c=1.839 nm,β=99.73°. The far-infrared spectra and the infrared spectra show that the amino group and carboxyl of valine may be coordinated to antimony and bismuth, respectively, in two compounds. The TG-DSC results also reveal that the complexes are formed.

    • Thermodynamics of Aldol Condensation of Acetaldehyde

      2011, 39(3):456-461. DOI: 10.3969/j.issn.0253-374x.2011.03.027

      Abstract (1568) HTML (58) PDF 874.29 K (1304) Comment (0) Favorites

      Abstract:The standard enthalpies of formation,the standard Gibbs free energy of formation and the heat capacity of each compound in acetaldehyde condensation reaction system were calculated with the application of Yoneda group contribution method.Comparison of the calculated results with some literature values show that the calculation results are reliable.Then the reaction enthalpies,reaction Gibbs free energy changes and equilibrium constants of relevant reactions in this system from 278 K to 368 K in liquid phase and 600 K in vapor phase were calculated and analyzed.The results show that the temperature has important influence on the main reaction.Conducting the reactions in liquid phase at low temperature benefited the main reaction,while high temperature led to low conversion and selectivity.2,4hexadienoic aldehyde was the main by-product.The thermodynamic analysis agreed well with experimental results.Acetaldehyde condensation is not recommended to proceed at high temperature.To improve the conversion and selectivity of practical reaction,the temperature is proposed be controlled reasonably or the main product needs to be separated from the reactant in time.

    • Direct Homogenization Method Based on Cosserat Elastic Theory

      2011, 39(3):462-466. DOI: 10.3969/j.issn.0253-374x.2011.03.028

      Abstract (958) HTML (39) PDF 899.36 K (750) Comment (0) Favorites

      Abstract:An analysis is made of the heterogeneous material with periodic internal structure with the mesomechanics direct homogenization method.Based on Cosserat theory,direct homogenization method is presented.The method is applied to the analysis of the plane homogenization problem of heterogeneous material with periodic internal structure,which verifies the method.

Current Issue


Volume , No.

Table of Contents

Archive

Volume

Issue

Most Read

Most Cited

Most Downloaded