bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and Properties of Conductive Epoxy Resin Composites
Authors: Ding Xin , Wang Hua , Tian Xing You , Zheng Kang
Published: March 2013

The conductive adhesives were prepared by using micron silver, ball-milled silver and the mixture of them as conductive fillers, respectively, and epoxy resin as matrix. In this study, The relationship between the resistivity with the content of silver fillers was tested. With the micron sliver loading from 60 wt% to 75 wt%, the resistivity decreases significantly about 8 orders of magnitude. And the effects of the different types of silver fillers (micron silver, ball-milled silver and the mixture of them) on the resistivity were also investigated. The study shows that the ECAs filled with the micron sliver gets the highest resistivity and the resistivity of ECAs which uses the ball-milled sliver as fillers is the lowest.
Fabrication and Characterization of Ag@C Nanocables with High Aspect Ratios by Hydrothermal Process
Authors: Li Yong He , Li Yu Jie , Fu Hao Yu , Zhang Yue Fei , Yang Li Zhen , Chen Qiang
Published: March 2013

Abstract. This paper describes that high-yield Ag/C coaxial nanocables has been obtained via a simple hydrothermal approach through the in situ reaction of Ag+ and glucose in the condition of CTAB. The glucose not only acts as reducing agent but also as carbon source. It was found that high aspect ratio(>400)of nanocables with Ag nanowires core diameter (20-60)nm and various carbon shell thickness had been prepared in large scale with a facile aqueous reduction route at low temperatures for different times. All of the products were characterized in detail by multiform techniques: X-ray diffraction(XRD), transmission electron microscopy(TEM), high-resolution TEM(HRTEM), scanning electron microscopy(SEM), energy-dispersive X-ray spectroscopy (EDX).
The Drag Reduction Characteristics of Hydrophobic Nanoparticles Adsorption Core Surface and the Prediction of Slip Lengths
Authors: Wang Xin Liang , Di Qin Feng , Gong Wei , Cheng Yi Chong , Hua Shuai
Published: March 2013

The slip model of micro channel in reservoir adsorbed by hydrophobic nanoparticles(HNPs) was established. The drag reduction characteristics were verified by the core slice adsorption experiment and core displacement experiment respectively. Results show that a compact HNPs adsorption layer can be built on the surfaces of the micro channel and the wettability of the surfaces can be changed from hydrophilic into strong hydrophobic. The slip lengths were calculated according to the slip model, the results show that the core surfaces can produce a slippage ranging from 6.7nm to 87.1nm, with an average of 43.3nm.
Detection of Ascorbic Acid with Microchip Electrophoresis
Authors: Yu Bing , Ren Yu Min , Cong Hai Lin , Zhang Mei Rong , Zhang Li Xin , Lian Li Fang
Published: March 2013

Currently, the fabrication of electrodes for microchip electrophoresis (ME) is rather complex. Usually, the electrodes have not been integrated completely with ME, which often lead to poor efficiency and reproducibility for the surface contamination. In this paper, we design and develop a new method for miniaturization of electrodes for ME. And the integrated microelectrodes show good detection performance for the ME analysis of ascorbic acid.
Composition Dependent Optical Properties of Zn1-xCdxS Nanostructures
Authors: Song Xue Yun , Wang Xiu Xi , Zeng Xiang Hua , Zhang Yong , Hu Yi Pei , Chen Hai Tao
Published: March 2013

Zn1-xCdxS alloy nanoparticles have been prepared via solvothermal approach. The effects of the mole fraction of Cd on the nanoparticles’ structure, size and photoluminescence spectra were investigated. It shows that with increase in mole fraction of Cd, the lattice structure of Zn1-xCdxS changes from cubic to hexagonal, and the size of these nanoparticles varied within 6-40nm. Room temperature photoluminescence measurements show an intense red shift from 518nm to 662nm. And the band gap energies from 2.3 to 3.54eV can be realized for the Zn1-xCdxS nanopartices. Furthermore, it is found that the conversion of Methylene Blue (MB) using Zn0.6Cd0.4S as the photocatalyst was up to 97% after 2h of irradiation.
Experimental Research of Mineral Processing on a Certain Lead-Zinc Oxidize Ore
Authors: Deng Wen , Zhao Hui , Jiang Deng Bang , Lan Yao Zhong
Published: March 2013

A certain multi-metallic lead-zinc oxide ore contains 1.09%Pb，8.39%Zn． The oxide rate of lead and zinc is 96.34% and 98.15% respectively．In order to recover valuable minerals from the oxide ore comprehensively, the authors adopted priority flotation processing in this experimental research. At last, the lead concentrate with Pb grade of 27.41% and the zinc concentrate with Zn grade of 24.14 % were respectively achieved. The overall recovery of lead was 93.66%，and the overall recovery of zinc was 90.74%.
Nonlinear Optical Properties of 0.7(Na1/2Bi1/2)TiO3-0.3(K1/2Bi1/2)TiO3 Thin Films Using Z-Scan Technique
Authors: Zhang Ting , Jia Cai Hong , Bai Ying , Zhang Wei Feng
Published: March 2013

Well-crystallized 0.7(Na1/2Bi1/2)TiO3-0.3(K1/2Bi1/2)TiO3 (NKBT) thin films were prepared on quartz substrates using a sol-gel process. The sign and magnitude of both the real and imaginary parts of third-order nonlinear susceptibility (3) of the thin films have been determined by the Z-scan technique performed at 532nm with picosecond laser. The nonlinear refractive index n2 and the nonlinear absorption coefficient of the thin films are determined to be 3.13×10-8 esu and 3.84×10-9 m/W, respectively. The real part and imaginary part of the third-order nonlinear susceptibility (3) of the sample were calculated and the values were 1.49×10-16 m2/V2and 3.96×10-18 m2/V2, respectively. The results suggested that the nonlinearity is dominated by the refractive for the films and the NKBT thin films is a promising material for applications in nonlinear optical devices.
Preparation and Characterization of Broad-Spectrum Sunscreens Loaded Nanostructured Lipid Carrier
Authors: Chen Yan Ling , Xia Qiang
Published: March 2013

A comprehensive photoprotective formulation was developed to enhance photoprotection ,compared to a conventional nanoemulsion ,having the concentration of two new molecular sunscreens, namely Diethylamino hydyoxybenzoyl hexyl benzoate(Uvinul ® A Plus) and Ethylhexyl triazone(Uvinul® T 150). In the present paper, the sunscreen mixture was incorporated into nanostructured lipid carriers (NLCs). After the production by hot high pressure homogenization, the NLC were analyzed in terms of particle size, physical state, particle shape, ultraviolet absorbance and stability. The particle size for all NLC was around 100-900 nm after production. The determination of 2 organic UV filters was performed by HPLC with UV spectrophotometric detection. The loading capacities for molecular sunscreens was up to 30%. In the sunlight, the retention rate of Uvinul ® A Plus and Uvinul ® T150 was still up to 80% after three months .
Degradation of Toluene Using Modified TiO2 as Photocatalysts
Authors: Yang Yang , Zhan Si Hui , Gao Xi Chao , Yang Shan Shan , Ren Guang Yuan , Li Yi , Jing Jing , Yu Hong Bing
Published: March 2013

Volatile organic compounds (VOCs), especially toluene as the typical indoor air pollutants, are toxic and environmentally persistent whose removal is undoubtedly becoming increasingly urgent matter over these years. Titania is one of the most promising photocatalysts for the degradation of organic compounds, whereas the large band gap of titania and massive recombination of photogenerated charge carriers limit its overall photocatalytic effciency. These defects can be tackled by modifying the electronic band structure of titania including various strategies like metal deposition, non-metal atoms substitution, transition metal ions doping, and coupling with a narrow band gap semiconductor, etc. This review encompasses several advancements made in these aspects, and also the influence factors such as physical morphologies changing, humidity, as well as the presence of O2 etc, are involved. To be practically considering, TiO2 photocatalysts require being ﬁxed on the bulky supports like silica, alumina, clays and activated carbons. Moreover, photocatalytic coatings deposited on external building materials, like rooﬁng tiles and corrugated sheets, is becoming the attractive application potentials to remove toluene from air.
Electrochemical Deposition and Properties Research of ZnO Thin Films
Authors: Wu Guang Ming , Ding Yao , Gao De Wen , Xing Guang Jian , Zhou Yang , Yin Tian Lan
Published: March 2013

The transparent ZnO films were deposited on the indium tin oxide (ITO) coated glass substrates by using the square wave potential deposition method. The conductive graphite plate is used for counter electrode, electrolyte consist of zinc nitrate and additive of electrochemistry, which is made up CTAB and potassium nitrate. Crystallinities of the films were examined by X-ray diffractometer. The morphologies of zinc oxide films were observed with atomic force microscope. Optical characteristics of zinc oxide layers were measured with UV–vis spectrophotometer. The optimal conditions for preparation of zinc oxide thin films with the square wave potential method were as follows: the deposition time was 6 min, concentration of zinc nitrate was 0.05mol/L, deposition temperature was 80 °C, and the annealing temperature was 500 º C. The average optical transmittance of the ZnO films is higher than 85% in the visible range. Moreover, the films have flat surface and small grain size.
Fabrication of Organized Mesoporous TiO2 Films Assembled via Different Template and Characterization of their Photocatalytic Activity
Authors: Li Dan , Du Bin , Zhao Zhi Heng , Jing Wen Heng , Xing Wei Hong
Published: March 2013

Hexagonal and cubic mesoporous TiO2 materials were synthesized via a sol-gel route modified by evaporation–induced self–assembly process with different templates. XRD and TEM results confirmed that the mesoporous films were highly organized. Furthermore, the hexagonal mesoporous TiO2 films were formed in the P123-templated films, whereas the cubic structure ones were found in the F127-templated films. Both the hexagonal and cubic mesoporous films showed photocatalytic activity in decomposing methyl orange solution under UV region, among which the cubic mesostructure presented superior potocatalytic activity because of larger surface area, more open framework and less obstructed diffusion paths of guest molecules.
Mechanics Study on Leveling Process by a Roller during Selective Laser Forming
Authors: Liu Jin Hui , Xie W.J. , Zhao C. , Zhang L. , Lu Z.L.
Published: March 2013

Generally, pressures resulted from roller during leveling process in selective laser sintering has the effect of densification of powder materials. But extra frictions due to them become the forces which always deteriorate the surface of the part and mark it with several lines trace. Sometimes, the manufacturing can even not continue if these forces accumulate to a large extent to move the whole part. Therefore, the whole forming process will be obliged to stop owing to the displacement of part from above mentioned damage. In this work, the emerging reason and related variation factors of these forces were studied mathematically, the mathematical and physical model of friction force was also built to describe the connections between the leveling process parameters and them. How to control the influence factor of friction to abate their damages to surfaces and promote the forming quality were also discussed based on these models. This will provide a common reference for the application of selective laser sintering technology.
Research on Character of Physical Field Distribution in High Speed Ball-End Milling Hardened Steel
Authors: Jiang Bin , Liu X.L. , Zheng M.L. , Yang Y.J. , Jiang L.
Published: March 2013

In order to mend cutting instability of ball-end milling cutter caused by the changes of cutting loads in high speed milling hardened steel, we perform the modal analysis and heat-force coupling field analysis of cutter, carry out the experiment of high speed milling hardened steel, investigate the character and effect factor of physical field distribution in high speed ball-end milling hardened steel, and propose the method about the match of diameter and overhang for depressing cutter vibration. Results indicate that the decrease in the ratio of overhang to diameter can transform the first modal shape of cutter from bending modal shape into torsion modal shape. The diameter of cutter is from 30mm to 20mm, the overhang of cutter is from 125mm to 90mm, heat-force coupling field distribution changes slightly, resonance of cutter does not occur, and efficiency in machining hardened steel can be improved effectively by higher cutting speed.
Study on Thermal Conductivity of Diffusion Layer of Coated Cutting Tools
Authors: Shen Hui Cun , Yang B.G. , Liang J.F.
Published: March 2013

Cutting temperature is the main factor to be considered in the select of coated cutting tools, so the study on the temperature of coated cutting tools is of practical significance. Diffusion layer of coated cutting tools has important implications on cutting heat generation and temperature distribution. In this paper, thickness of diffusion layer is determined by making use of spectrum analysis method to observe elements diffusion between coating and substrate of coated cutting tools. By dividing the diffusion layer into two parts on both sides of interface of coating and substrate, diffusion layer model is established. By integrated use of calculation method of Maxwll-Eucken model, Series model and equivalent thermal conductivity of multi-layer materials, thermal conductivity calculation formula of diffusion layer is derived. Method of thermal conductivity calculation when combining coating and diffusion layer into a whole layer is also put forward. Results of this paper have wide significance for experiment and simulation study on coated cutting tool temperature.
Synthesis of Ca3 (VO4)2:Eu3+, Bi3+ Nanophosphors in the Presence of Stearic Acid
Authors: Wang X.J. , Fu X.G.
Published: March 2013

Ca3(VO4)2:Eu3+,Bi3+ nanophosphate was prepared in the presence of stearic acid. The samples obtained were intensively characterized using XRD, SEM, photoluminescence (PL) spectra and FTIR. The results show that the red emission located at about 614 nm was ascribed to 5D0–7F2 transition of Eu3+, and the excitation and emission spectra indicate that this nanophosphor can be effectively excited by ultraviolet (UV) (395 nm), and exhibits a satisfactory red performance (614 nm), nicely ﬁtting in with the widely applied UV LED chips.
Research and Realization of a New Algorithm for Stereo Matching Based on Binocular Vision
Authors: Cheng Jun Ting , Zhao C. , Zhao W.L. , Wu W.H.
Published: March 2013

In the development of a three-dimensional measurement system, binocular stereo matching is the most important and difficult. In the basis of introducing selective principles of matching algorithm, a new stereo matching algorithm for binocular vision is put forward that is named noncoded difference measuring distance. The algorithm effectively grapples with the problem of searching for the coincidence relation of raster and can efficiently and accurately obtain three-dimensional world coordinates of the entities. Experiment results show that this 3D measuring machine can effectively measure the 3D solid profile of free surface. During the evaluation test for accuracy, scan a standard plane. Fit all 3D points in one plane, and then the flatness value of this plane is obtained. The flatness value of the standard plane has been ultimately measured as: ± 0.0462mm, this measuring accuracy can completely satisfy the requirements of rapid prototyping or CNC machining, it as well as achieves the stated accuracy (± 0.05mm).
Study on the Computer Modeling Technology of Die Design and Engineering
Authors: Huang C.Y. , Fu X.G.
Published: March 2013

UML modeling technology combines static modeling process (object graph) and dynamic modeling process (cooperation figure, sequence diagram), and the dynamic modeling process makes static modeling process move forward. This paper introduces the geometrical modeling technology of CAD/CAM, feature modeling technology, the characteristic modeling technology of UML and the application in the mould design.
Forming Principle and Error Analysis of Ballscrew Manufactured by Cold Rolling
Authors: Wang X.Q. , Cui F.K. , He X.J. , Xu H.Y.
Published: March 2013

Cold rolling is an advanced splinterless processing method, which has been applied to process many parts, like spur gears, helical gears, spline shaft and ballscrew, etc. Ballscrew which determines the motion characteristics has been used as key transmission part of ballscrew pair. According to differential geometry and meshing theory, the mathematic model of ballscrew manufactured by cold rolling is built, and the normal section equation of ballscrew is derivated in this paper. The cold forming principle of ballscrew is investigated; the meshing model, the contact line and theoretical errors of the ballscrew are constructed. The objective moving laws between roller and workpiece are revealed by analyzing the meshing model and the contact line, the processing method of cold-rolling is considered as the generating method which can lay the foundation for roller design by analyzing forming principle. By analyzing the profile error and the error of the actual helix of the centrode of ball, the error generation causes are discovered, and the calculation methods of the profile error and the spiral error of ballscrew are proposed. By analyzing the error evolution and taking a certain type of ballscrew for example, the results indicate that the profile error is brought by roller designing, and the spiral error is caused by discontinuous contact.
Research on Static and Dynamic Performance of Large-Span Steel Trestle
Authors: Wang Hui , Cheng Ming Hui
Published: March 2013

To study the static and dynamic performance of large-span steel trestle, the steel trestle space finite element model was established with the consideration of the element coupling. The normal stress distribution of trestle bars under the static action was calculated.Combined with subspace iteration method and the time- history analysis, the trestle vibration modal and the dynamic stress extreme value of main bars were analyzed. The structure is more sensitive to transverse earthquake, and under the existing conditions the bar stresses are controlled in allowable range, the structure is safe and reliable.
Evaluation of Compressive Strengths of HPS Plate Systems Stiffened with Trapezoidal Stiffeners
Authors: Shin Dong Ku , Kim Kyungsik
Published: March 2013

The ultimate compressive strengths of high performance steel (HPS) plate system stiffened longitudinally by closed stiffeners have been investigated by the nonlinear finite element analysis. Both conventional and high performance steels were considered in models following multi-linear strain hardening constitutive relationships. Initial geometric imperfections and residual stresses were also incorporated in the analysis. Numerical results have been compared to compressive strengths from Eurocode 3 EN 1993-1-5 and FHWA-TS-80-205. It has been found that although use of Eurocode 3 EN 1993-1-5 and FHWA-TS-80-205 may lead to highly conservative design strengths when very large column slenderness parameters are encountered
Effect of Shield Tunneling on Existent Piles in Soft Soil Area
Authors: Cao Yong Hua , Zhuge Ai Jun
Published: March 2013

In urban environment, short-distance crossing of shield tunneling to existent piles is an unloading process and can cause adverse effect on the piles. This kind of effect should be controlled. To analysis and control this effect, numerical simulation, field monitoring and optimization of construction parameter were used in this study. To get reasonable calculation parameters for numerical models, field monitoring was conducted. The numerical simulation was utilized to study the process of short-distance crossing and the effect of ground improvement with rotary jet grout pile. The simulation result revealed that the ground improvement is not necessary in soft soil if the pile is long enough. In the later practical tunneling process, the ground improvement in the initial design was canceled. Construction parameters were adjusted in time, such as the strict controlling of synchronized grouting, secondary grouting, rotation speed of cutter head and driving speed. As a result, the displacement of the existent piles was controlled in the tolerable ranges.
Study on the Geological Forecast and Treatment for Water-Bearing Fault of the Qingdao Kiaochow Bay Subsea Tunnel
Authors: Li Zhi Peng , Li Shu Cai , Zhang Qing Song , Wang De Ming , Hui Bing , Zhang Wei Jie , Liang Yao Hui
Published: March 2013

Water-bearing fault of subsea tunnel has fissure water developed, fractured surrounding rock with low strength, which gets a risk of sudden water inflow and affects the tunnel security. This paper takes the geological forecast and treatment for water-bearing fault of the Qingdao kiaochow bay subsea tunnel for example, according to the water assignment characteristics, using the detect method of TEM and advance borehole to make accurate decision for the position of water-bearing body、the scale of fracture zone and the inflow of water. Through the analysis of results, the grouting form, materials and parameters are chosen and adjusted. The grouting material seals the water flowing fracture, forming water-stopping curtain outside tunnel excavation contour line and strengthening the fault fracture zone to improve the stability of rock.
The Study on the Control of the Early-Stage Crack of the Concrete Poured in Winter in Shenyang Subway
Authors: Han Li , Zhao Wen , Zhao Yu
Published: March 2013

The control of concrete crack is a complicated and difficult problem for civil engineering. It is more difficult to control the crack of the concrete poured in winter. Thorough the analysis of the construction of Shenyang subway in winter, a combination of methods are applied. Frost proof and decreasing the temperature stress of concrete are considered together. The combination of antifreezing measures and decreasing the temperature stress of concrete make the construction quality arrive a satisfying level.
Dynamic Properties of High-Speed Turnouts under Foundation Settlement
Authors: Cai Xiao Pei , Qiu Jin Shuai , Liu Han Qian
Published: March 2013

Foundation settlement of high-speed turnouts has a significant impact on its security serve status. Based on the general finite element software ABQUS, a vehicle-turnout-roadbed coupled dynamic model was built, and the dynamic properties of NO.18 movable-point turnout were analyzed in this paper. The result shows that: the acceleration of switch rail and nose rail is larger than that of track in common section under foundation settlement; large vibration and deformation of the track structure arise when the vehicle is going through, meanwhile the peak of foundation lateral vibration response is higher than that of vibration caused by the vehicle passing switch rail. The derailment coefficient, rate of rail load reduction, the acceleration and displacement of track plate and foundation all increase with the settlement of foundation. On the contrary, they reduce as the length of subtense. Also, the dynamic response of high-speed turnout grows along with the speed of the increasing under foundation settlement.
Method of TER Location for High-Grade Highway Based on Fuzzy Rough Set
Authors: Li Chao , Wang Yu Lan
Published: March 2013

The location technology of Truck Escape Ramp(TER) is the important guarantee for fully developing the TER actions and ensuring operation safety of heavy vehicles on long-steep downgrade. In order to improve the precision of TER location, this paper thoroughly analyzed the influence factors of TER location from the view of traffic accidents statistical data, road conditions and vehicle status. Expounded the theory of fuzzy rough set. Put forward the method of highway TER location based on fuzzy rough set. Used this method to evaluate the running safety of the unit sections on the long-steep downgrade. Calculated the comprehensive safety index values of sample sections and made ones with high comprehensive safety index values as the candidate sections for TER. Determined the accurate positions of the TER based on comparison of the comprehensive safety index value of adjacent candidate sections. Setting effect shows that the TER position determined by the method are scientific and rational.
Soil Layer Settlement Experimental Study of Dynamic Compaction in Aeolian Sand Foundation
Authors: Zhang Jian Hui , Feng Zhen , Yang Pei Xuan
Published: March 2013

A study on the soil layer settlement of the aeolian sand foundation treatment by dynamic compaction is reported. The site soil conditions and the dynamic compaction settlement test were introduced. The change curves of the ground surface settlement on the impact point in the course of tamping and the soil layer settlement beneath the impact point after tamping were given. It was found that the ground surface settlement along with number of drops can be described by the hyperbolic function, and the soil layer settlement along with the depth can be described by exponential function. Other some meaningful conclusions were also obtained.
The Application of Gray Theory on Predicting the Settlement of High Embankment
Authors: Jin Ju , Dou Yuan Ming , Li Qi Nan
Published: March 2013

Stability of the road embankment is the foundation of the highway normal operation and maintenance, so there is strict requirement of road subgrade settlement for the highway. This article uses the gray theory to predict Cheng Chi high embankment construction settlement and builds a predicted model and tests the model’s accuracy. The results of settlement prediction are under the limits, so the stability of the road subgrade is good. This dynamic prediction method can be used on prediction of the settlement of high embankment and it’ll direct the operation and ensure the maintenance safety.
Effect of Aging on Urban Asphalt Pavement
Authors: Li Ning Li , Zhao Xin Po , Du Chuang , Zhang Cai Li , Xiao Qing Yi
Published: March 2013

The aging of asphalt pavement gets serious in the course of service due to the large number of vehicles and high pavement temperature. A survey was conducted on urban road’s asphalt pavement in the city of Tianjin. By analyzing the extracted asphalt sample from asphalt pavement built in different years, it shows that asphalt’s softening point and viscosity increase but its penetration and ductility attenuate with the extension of service period. Of which, the ductility changes dramatically with its ductility attenuating fast in the early years of service and the attenuation of ductility tending to slow down later. The vertical difference of aging in different depth of pavement is marked and degree of aging tends to attenuate from the surface to the center.
Applied Research of the Steel Frame-Shear Wall System in the Primary and Secondary Schools
Authors: Zhu Mo , Tao Zhong , Zhang Min , Li Ling Xu
Published: March 2013

Steel frame - shear wall structure of the teaching building has been by the software PKPM respectively in the design basic acceleration of ground motion of 7~9 degrees, include story drift, component stress, overturning moment and the amount of steel. Comparative analysis shows that the main factors affect the stress ratio is related to the sectional dimension, and has little to do with the intensity. By calculating the overturning moment, it proved that in 9 degree 0.4g and 8 degree 0.3g, the frame with shear wall structure combined with a relatively close. The structure not only meeting the earthquake disaster prevention requirements of the teaching building in highly seismic region, but also the structure has good economic applicability.
The Seismic Reinforcement Measures of through Type Timber Frame Joint Based on the Earthquake Damage Survey
Authors: Li Ling Xu , Tao Zhong , Qin Liang Bin , Zhu Mo , Tian Rui , Duan Xu
Published: March 2013

Via the field investigation about farm building built on rural areas after the 2009, Ms=6.0 Yaoan earthquake in Yunnan province, China, the seismic damage of raw-soil structure and wooden structure have been put forward. Additionally, combined with the earthquake damage survey about the 1996 Lijiang and 2007 Ninger earthquake in Yunnan province, the seismic reinforcement schemes are proposed and appropriate costs are analyzed.
The Fluid-Solid Coupling Analysis of Aqueduct Imposed Multi-Point Seismic Waves
Authors: Kong Lin , Zhang Mei Ying , Shi Bei Xiao
Published: March 2013

So the consistent seismic wave model and multi-point seismic wave model are established based on the solid-fluid interaction theory in this paper. According to the analysis of the seismic response, the results show that: the effect on the dynamic response of the aqueduct in the soft site is greater when the seismic wave velocity is small. Therefore, in the seismic study of long-span structures, when the wave velocity is smaller, it is critical to consider the effect of the earthquake's multi-point input, so that the results can be coincident with the actual situation.
Experimental Instruments and Results’ Analysis of a Shaking Table Model Test for a Complex High-Rise Building
Authors: Chen Yue
Published: March 2013

Standing 250m above the ground level, the tower employs a complicated modern tall building system that involves the use of a reinforced core, two strengthened trusses and eight composite (concrete encased steel) mega-columns in the exterior perimeter of the building to resist vertical and lateral loads. A shaking table model test was carried out according to owner’s commission due to its complexity and the requirement of the Chinese Design Codes. In this paper, test equipments and test results were analyzed and some conclusions were given. The method applied in this model test will be helpful to other similar experimental studies.
A Wavelet Collocation Precise Integration Method for Laminated Rectangular Plates with Four Sides Clamped
Authors: Zhang Hong Wei , Wang Yan Li , Qing Guang Hui
Published: March 2013

By using Quasi-Shannon wavelet, we develop a wavelet collocation method for the Hamilton canonical equation of elastic bodies, and get the Hamilton canonical equation which is discrete in the plane of the rectangular laminated plate and continuum along its thickness. The approximate solution expressed by Quasi-Shannon wavelet satisfies the clamped boundary conditions of the plate easily. Hence, it is convenient to establish the wavelet collocation precise integration method for the static problem of the rectangular laminated plate with four sides clamped. Numerical results show that the current approach offers excellent predictive capability for rectangular composite laminated plate with clamped boundary conditions.
The Relationship between High Fluorine Groundwater and Geological Environment in Gaomi
Authors: Gao Zong Jun , Zhu Xi , Tian Yu , Ma Yang Min , Li Jia Jia
Published: March 2013

Drinking fluoride water is the root cause of serious endemic fluorosis in Gaomi. According to the investigation and sampling test, this paper analysis the relationship between high fluoride water and stratigraphic units and topography: in stratigraphic, high fluoride areas, heituhu Formation and the Yihe Formation are consistent; in topography, high fluoride areas and flood plain landscape are matching. Thus we can summarize the conditions for the formation of high fluoride water. Depending on the analysis of the data, this paper points out the relationship between the fluorine and other elements in the water, especially the fluorine’s close relationship with Mg, Se, Sr. Countermeasures Measures and suggestions on fluoride removal are also provided.
Lateral Buckling Studied of Rectangular Plate with Two Opposite Edges Clamped under the Action of a Concentrated Loads
Authors: Wu Song Jin , Jiang Li Qiang , Yuan Wei Ning
Published: March 2013

This study is focus on investigating the lateral buckling of the rectangular plate with two opposite edges clamped under the action of concentrated load. A analytical method of thirty rectangular plate which fixed at two opposite edges with one hundred and fifty buckling modality of concentrated load has been calculated by using the ANSYS finite element software. The curves of lateral buckling minimum critical load could be achieved by the calculation. Compared with the results from the existing calculation formula, the limitation applicability of the formula would be determined. To have a better agreement with ANSYS analysis results, this formula would be corrected by the analysis of the comparison between existing formula and ANSYS results. This research could provide effective methods for engineering design.
Stability of Implicit Midpoint Algorithm Applied to Structures with Nonlinear Damping
Authors: Pan Tian Lin , Wu Bin , Chen Yong Sheng
Published: March 2013

Stability of implicit midpoint algorithm applied to solving the equation of motion with nonlinear damping. The analytical and numerical study exhibit the unconditional stability of implicit midpoint scheme for nonlinear damping systems. The work of the present paper provides theoretic base for further application of this implicit midpoint approach.
Underlying Surface Influenced on the Landslide Runout
Authors: Fan Xiao Yi , Zeng Yao Xun , Duan Xiao Dong
Published: March 2013

The landslide runouts not only were controlled by the volumes and vertical movement distances, but also the underlying surface played an important role. The concave, fold line, ladder and bedded types of the landslide underlying surfaces were studied. It aimed at analysis the underlying surfaces influenced on the runouts of the catastrophic landslides. There was significant correlation between the horizontal distances and the volumes, vertical distances in the seismic and rainfall landslides without river blocking. But the relationships showed different power laws in the seismic and rainfall landslides. The relative errors between actual and forecast values of seismic and rainfall landslides reflected that the underlying surface types influenced on the landslide horizontal movement distances. The results showed that the maximum horizontal distances of seismic and rainfall landslides could be predicted based on the landslides volumes, vertical distances and underlying surfaces.
Chloride Ion Diffusion Behavior of Concrete after Freezing and Thawing Cycles
Authors: Qu Feng , Niu Di Tao
Published: March 2013

With repeated action of freeze-thaw cycles, chloride ion diffusion characteristics changed obviously in concrete structure. In the study, the chloride ion diffusion coefficient and the surface chloride ion concentration were discussed especially with the trends. Based on these facts, the chloride diffusion model and the improved model of concrete was also discussed based on its time-dependent characteristics, which indicated that the freeze-thaw damage of concrete would have a greater impact to the chloride transport course in the concrete, and so on the service life of concrete structures would be affected.
A New Measuring and Calculating Method for Concrete Thermal Conductivity with Multipoint
Authors: Qiang Sheng , Wu Chao , Zhang Nan Nan , Xie Zhi Qiang
Published: March 2013

The real thermal parameters always have inevitable influence on the simulation results of the structure thermal field and stress field in the construction of mass concrete. A new measuring and calculation method for concrete thermal conductivity was put forward. Eight or six sensor points measuring method and calculation formula are present, and the latter is the simplification of the former. Comparing the real thermal conductivity with the calculation result by the new method, it can be seen that the thermal conductivity can be obtained within about 6 day’s age at site and with the accurate degree of 98%. The new method will provide an efficient way for the concrete structure researcher and designer.
A Simplified Concrete Damage Constitutive Model
Authors: He Jian Ping , Chen Wei Zhong
Published: March 2013

In view of the limitation of seismic damage model for concrete structures with recent methods, based on Drucker-Prager constitutive model, with the concept of damage surface, Mazars concrete damage equation obtained by uniaxial test was extended to the triaxial state. Material stiffness damage degradation impact on the yield process of concrete yield surface was considered. Given Druker-Prager constitutive model adapted to the low friction angle soft clay type, the yield parameters threshold of yield surface is low that does not meet the concrete reality, draw double-shear strength theory, the strain threshold of double shear strain yield equation has been adopted, Modified damage threshold of uniaxial test strain damage equation. This paper developed a simplified concrete damage constitutive model in FLAC3D environment. The model is simple and easy to practical engineering applications, and the model has a certain accuracy. Try to explore a new constitutive model of concrete.
A Neural Network Approach for Estimating Model Parameters of Rockfill Materials
Authors: Wang Ji Zhe , Su Ying Feng
Published: March 2013

The Duncan-Change constitutive model of rockfill materials is used to characterize the behaviors of modeled rockfill materials. A parameter estimation procedure based on neural network is developed. The material parameters for the rockfill materials are determined from the experimental results of triaxial compression. The investigation results reveal that the identified model parameters can provide satisfactory prediction of the behavior of the rockfill materials tested.
Nanostructural Layer and Properties of 35 CrMo Steel Rolled by Cross-Rolling
Authors: Xiao Juan , Wu Run , Rao Cong Sheng , Zhao Ming Huan , Song Shu Peng , Wang Zhong Ping
Published: March 2013

A nanostructural layer was formed on the surface of 35CrMo steel rods rolled by cross-rolling. The layer microstructure is composed of nano-scale grains and some deformation grains, which contains compressive residual stress of -479Mpa. The surface roughness is decreased from Ra 2.1μm to Ra 0.14μm with improvement of the cylindricity and straightness. The rolling strengthenes the surface but has ignorable influence on the mechanical properties of the rods.
Study on Expansion Rate Assessment Method for Sulfate Resistance of Cementitious Material
Authors: Gu Kun Peng , Wang Cheng Qi
Published: March 2013

By means of testing expansion rate of different cementitious material under the sulfate corrosion experimental conditions, sulfate resistance of cementitious material and assessment method are studied. The results show that expansion rate of cementitious material increased with corroded age, and the assessment method is put forwarded. Sulfate resistance of cementitious material can be divided into five classes according to expansion rate assessment method as follows: "very low", "low", "moderate", "high" and "very high". The sulfate resistance of Portland cement is better than ordinary Portland cement, and both of them are very low. Mineral admixture with proper content can improve sulfate resistance of cementitious materia largely. Sulfate corrosion mechanism of different kinds of cementitious material is analyzed.
A Study on the Effect of Initial Shear Stress on Dynamic Properties of Saturated Clay
Authors: Qi Jian Feng , Yuan Ying , Wang Zht
Published: March 2013

Through a series of tests on saturated remoulded clay, initial shear stress on dynamic shear modulus and damping ratio under the condition of large strain(>10-3) is examined. The test data indicate that initial shear stress effects on stress-strain relation and dynamic modulus and damping ratio are obvious. With the initial shear stress increasing, the characteristic of the stress-strain relation changes from cyclic deformation to accumulative deformation, and there is difference in variation pattern of dynamic shear modulus and damping ratio with cyclic number increasing.
Performance Research on Ultra-High Performance Self-Compaction Concrete (UHP-SCC)
Authors: Xu Li Bin , Feng Nai Qian , Guan Bee Ir. Dr. Ch'ng
Published: March 2013

With development of concrete technology, the self-compaction concrete, as a green material, has been studied and widely applied thanks to its characteristics like self-leveling, self-compacting and desirable fillability. At present, high performance and ultra-high performance is an important trend in development of self-compaction concrete technology. Working performance, physical performance, endurance quality, ultra-high pumpability and microstructure of C100UHP-SCC are studied in this paper. The initial fluidity of studied UHP-SCC reaches above 550mm and maintains for 3h without loss, its compressive strength on 28d is more than 100MPa, which can ensure the architectural structure to last for 100 years and enable ultra-high pumping over 400m. The technical parameters mentioned above provide valuable reference for design and construction of super high-rise buildings which are above 1000m.
Application of Infra-Red Thermography to the Analysis of Construction of the Valencian Rammed Earth Walls of The Seminary-School of Corpus Christi in Valencia (Spain)
Authors: Lerma Carlos , Mas Ángeles , Gil Enrique , Galiana Mercedes
Published: March 2013

Infra-red thermography is widely utilised in the restoration of buildings. This article presents a novel method in the application of thermography to the analysis of rammed earth walls, and the Valencian rammed earth wall, or tapia valenciana, in particular. For this study, the authors chose The Colegio de Corpus Christi de Valencia (Spain). First, an analysis of costs incurred during the construction of the Colegio (built 1586-1610) was carried out. Second, thermographic techniques were utilised to gather further data on its construction process and corroborate information appearing in historical records. The rammed earth walls of this large building rest upon a stone footing. This study proposes a methodology that can be extensively applied to other similar studies with a view to understanding construction processes.
Study on Gluing Properties and Surface Wettability of Radial Bamboo Strips
Authors: Du Chun Gui , Jin Chun De , Li Guang Yao
Published: March 2013

This paper presents the studies on surface contact angles of water and phenolic resin and bonding strengths of three kinds of radial bamboo strips and chordwise bamboo strips. The results showed: water and phenolic resin could better wet radial bamboo strips, and wettability and gluing properties of the base radial bamboo strips were best, the middle radial bamboo strips followed, the tip radial bamboo strips ranked third in the three kinds of radial bamboo strips; wettability of water and phenolic resin and gluing properties of chordwise bamboo strips were better than radial bamboo strips.
Quantitative Characterization of 3D Pore Structure in Porous Limestone
Authors: Ji Yun Tao , Baud Patrick , Wong Teng Fong , Liu Li Qiang
Published: March 2013

The pore structure in intact and inelastically deformed Indiana limestone have been studied using x-ray microtomography imaging. Guided by detailed microstructural observations and using Multi-level Otsu’s thresholding method, the 3D images acquired at voxel side length of 4 μm were segmented into three domains: solid grains, macropores and an intermediate zone dominated by microporosity. Local Porosity can be defined to infer the porosity of each voxel. The macropores were individually identified by morphological processing and their shape quantified by their sphericity and equivalent diameter. With this segmentation, we obtained statistics on macropores on intact and deformed Indiana limestone which shows that inelastic compaction was followed by a significant reduction in the number of macropores. And also our results revealed the great potentiality to produce a quantitative analysis on porous material with the aid of micro CT images.
Test and Analysis on the Wearability of Bamboo Pulp Fabric
Authors: Ma Shun Bin
Published: March 2013

In order to have a better understanding the wearability of bamboo pulp fabric and enhance the research and development level of this kind of products, the fabric performances such as the strength, elongation, air permeability, moisture permeability have been test and discussed in this paper. The results shown that: the breaking strength of fabric increases when the bamboo pulp fiber content reduces; when the bamboo pulp fiber content increased, the breaking elongation, wear resistance performance, wicking performance, crease recovery performance, moisture permeability, air permeation rate and tearing strength of fabric also increased.
On Study of Development Expansive Coal Gangue Portland Cement by Microwave Technology
Authors: Zhao Zhi Man , Wang Qian , Wang Chun Jie , Zhang Xiao Mei
Published: March 2013

Added carbon powder or M mineral powder in unburned kaolinite coal gangue, the mixtures could be changed better expansive mineral additive of Portland cement by microwave irradiation. The microwave activation coal gangue mixtures 5%, 10%, 15%, 20%, 25%, 30% and 35% (by weight) were respectively added intoⅠ42.5 Portland cement. The compressive/flexural strength of various expansive coal gangue Portland cements were determined after 3 and 28 day. The fineness, initial and final setting time, soundness and volume expansive ratio was also measured. 　　　The expansive reasons of coal gangue Portland cement were considered that there were lots of thicker and bigger flaky crystal during hydration processes by scanning electron microscope, and found the Al, Si, O and other elements in flaky crystal by Edax. 　　　The expansive mechanism of coal gangue Portland cement is different from traditional expansive cements theories by microwave irradiation.
Infrared Spectrum Test and Analysis of Regenerated Cellulose Fibers
Authors: Ma Shun Bin
Published: March 2013

In this paper, the infrared spectrum of regenerated fibers have been tested and analyzed, such as Lyocell fiber, Modal fiber, regenerated cellulose fiber and Bamboo pulp fiber. Test results shown that: Lyocell fiber, Modal fiber, Bamboo pulp fiber are similar to viscose fiber in their infrared spectrogram, but the transmittance of characteristic absorption peaks of them are different.
Construction Technology and Organization of Jiande Yangxi Main Bridge
Authors: Jiang Xi , Yu Tian Qing
Published: March 2013

The Yangxi main bridge for 49+120+49 m the self-anchored suspension bridge, the main girder procedure full framing in situ girder construction, bridge tower using piecewise casting method construction, use scaffolding as construction operation platform. Main cable construction using prefabricated parallel wire strand method (PPWS), first within the plant into steel wire strand, roll in the drum on delivery to the bridge site erection points, with traction rope by stock installation in place. Saddle the fission lifting, cable clamp installed application to the calibration of jack import screw tension 420 kn, and three times repeated tension, sling the factory-made after installation in place. Can be used as the same bridge comparison and reference.
Applications of Fiber Grating in Temperature Measurement of Hydration Heat of Concrete
Authors: Tang Xian Xi , Liang Jin Bao , Tang Xian Zhou , Guo Wei , Xu Yue
Published: March 2013

In order to verify the application effect of fiber grating strain gauge in concrete hydration heat measurement, the relevant experimental researches were carried out. First, according to the formulas of concrete condensation hardening adiabatic temperature rising, the regulation of temperature changes in the concrete condensation hardening process was calculated. Then the observation results of concrete condensation hardening temperature by fiber grating were analyzed, and the variation regulation observed was summarized, and the variation regulation was verified by temperature sensors embedded in the corresponding positions. The results of the study shown that, the measured data by fiber grating can reflect the temperature change rule of concrete well. Therefore, it was feasible to measurement the temperature change regulation by fiber grating.