Dynamic Characteristics of Long -Span Steel -Concrete CompositeBeam Bridge Based on Vehicle -Bridge Coupling Effect

In order to investigate the effect of vehicle-bridge coupling on the dynamic characteristics of the bridge,a steel-concrete composite beam suspension bridge is taken as the research object,and a three-dimensional spatial model of the bridge and a biaxial vehicle model of the vehicle are established,and then a vehicle-bridge coupling vibration system is constructed on the basis of the Nemak-βmethod,and the impact coefficients of each part of the bridge are obtained under different bridge deck unevenness and vehicle speed.The simulation results show that the bridge deck unevenness has the greatest influence on the vibration response of the bridge,and the bridge impact coefficient increases along with the increase in the level of bridge deck unevenness,and the impact coefficient of the main longitudinal girder and the secondary longitudinal girder achieves the maximum value when the level 4 unevenness is 0.328 and 0.314,respectively;when the vehicle speed is increased,the vibration response of the bridge increases and then decreases,and the impact coefficient of the bridge in the middle of the bridge at a speed of 60 km/h achieves the maximum value of 0.192.

Crust-Mantle Structure and Coupling Effects on Mineralization : An Example from Jiaodong Gold Ore Deposits Concentrating Area, China

Based on the results of two dimension velo city structure, 1∶100 000 aeromagnetic anomaly, 1∶200 000 bouguer gravity anom aly and seismic anisotropy of Jiaodong and neighboring region in Shandong, China , the information of geophysical field was divided into two parts: deep and sh allow focus fields. And then, the information of two different fields was c ombined with that of deep seated geology and ore deposit features. The syntheti c result was adopted to analyze three dimension structure, to probe into crust mantle coupling effects of mineralization and dynamics of ore formation system .

NUMERICAL STUDIES ON RESONANT AND ENHANCEMENT EFFECTS FOR COUPLING OF MICROWAVE PULSES INTO NARROW SLOTS

In this paper, modifications to the finite-difference time-domain(FD-TD) method for modeling microwave pulse coupling into a slot, which is much narrower than one conventional FD-TD cell, are discussed. The coupling process of microwave pulse into a slot is studied by using the modified FD-TD method, and the dependence of microwave coupling on slot sizes, the carrier frequencies and the polarization directions of the incident waves is analysed. Resonant and enhancement effects which occur in this process are observed. The condition at which the resonant effect takes place is also presented.

Coupling Effects of Irrigation and Phosphorus Fertilizer Applications on Phosphorus Uptake and Use Efficiency of Winter Wheat

The water content and nutrient in soil are two main determine factors to crop yield and quality, managements of which in field are of great importance to maintain sustainable high yield. The objective of this study was to measure the uptake, forms, and use efficiency of phosphorus （P） in wheat under four levels of irrigation （W0, W1, W2, and W3） and three levels of P application （P0, P1, and P2） through two growth seasons of wheat （2008-2010）. The field experiment was carried out in a low level of soil P concentration and the eultivar was Jimai 20. The results indicated that P fertilizer combined with irrigation not only improved the activity of phosphatase in soil, but also increased P accumulation in wheat, similar results was found in the grain of wheat, the content of total P increased significantly. Meanwhile, the mainly existence forms of P in grain were the lecithoid-P and labile organic-P. On the other hand, in comparison to the irrigation, the dry matter and grain P production efficiency and postponing P application of wheat increased with increasing Papplication rates within the range of 0-180 kg P2O5 ha-1. The interaction between P and irrigation also significantly （P〈0.01） affected on the P accumulation, grain total P, grain phospholipid P, and P production efficiency. In this study, therefore, the P applications and irrigation improved grain P production efficiency and postponing P application of winter wheat, and W2P2 treatment （180 kg P2O5 ha-1 combination with 120 mm irrigation） had a high P accumulation and P use efficiency, it was an optimum level for P fertilizer application and irrigation in this region.

Coupling Effects of A Deep-Water Drilling Riser and the Platform and the Discharging Fluid Column in An Emergency Disconnect Scenario

As drilling operations move into remote locations and extreme water depths, recoil analysis requires more careful considerations and the incidence of emergency disconnect is increased inevitably. To accurately capture the recoil dynamics of a deep-water riser in an emergency disconnect scenario, researchers typically focus on modelling the influential subsystems (e.g., the tensioner, the mud discharge and seawater refilling process) which can be solved in the preprocessing, and then the determined parameters are transmitted into an existing global riser analysis software. Distinctively, the current study devotes efforts into the coupling effects resulting from that the suspended riser reacts the platform heave motion via the tensioner system in the course of recoil and the discharging fluid column follows the oscillation of the riser in the mud discharge process. Four simulation models are established based on lumped mass method employing different formulas for the top boundary condition of the riser and the discharging flow acceleration. It demonstrates that the coupling effects discussed above can significantly affect the recoil behavior during the transition phase from initial disconnect to the final hang-off state. It is recommended to develop a fully- coupled integrated model for recoil analysis and anti-recoil control system design before extreme deep-water applications.

Electron Momentum Spectroscopy of Valence Orbitals of n-Propyl Iodide： Spin-Orbit Coupling Effect and Intramolecular Orbital Interaction

The binding energy spectrum and electron momentum distributions for the outer valence orbitals of n-propyl iodide molecule have been measured using the electron momentum spectrometer employing non-coplanar asymmetric geometry at impact energy of 2.5 keV plus binding energy. The ionization bands have been assigned in detail via the high accuracy SACCI general-R method calculation and the experimental momentum profiles are compared with the theoretical ones calculated by Hartree-Fock and B3LYP/aug-cc-pVTZ（C,H）6-311G？？（I）. The spin-orbit coupling effect and intramolecular orbital interaction have been analyzed for the outermost two bands, which are assigned to the iodine 5p lone pairs, using NBO method and non-relativistic as well as relativistic calculations. It is found that both of the interactions will lead to the observed differences in electron momentum distributions. The experimental results agree with the relativistic theoretical momentum profiles, indicating that the spin-orbit coupling effect dominates in n-propyl iodide molecule.

WAVE-SOIL-PIPE COUPLING EFFECT ON SUBMARINE PIPELINE ON-BOTTOM STABILITY

Wave-soil-pipe coupling effect on the untrenched pipeline stability on sands is for the first time investigated experimentally. Tests are conducted in the U-shaped water tunnel, which generates an oscillatory how, simulating the water particle movements with periodically changing direction under the wave action. Characteristic times and phases during the instability process are revealed. Linear relationship between Froude number and non-dimensional pipe weight is obtained. Effects of initial embedment and loading history are observed. Test results between the wavesoil-pipe interaction and pipe-soil interaction under cyclic mechanical loading are compared. The mechanism is briefly discussed. For applying in the practical design, more extensive and systematic investigations are needed.

A continuum traffic flow model with the consideration of coupling effect for two-lane freeways

A new higher-order continuum model is proposed by considering the coupling and lane changing effects of the vehicles on two adjacent lanes. A stability analysis of the proposed model provides the conditions that ensure its linear stability. Issues related to lane changing, shock waves and rarefaction waves, local clustering and phase transition are also investigated with numerical experiments. The simulation results show that the proposed model is capable of providing explanations to some particular traffic phenomena commonly observable in real traffic flows.

Numerical simulation of the effect of coupling support of bolt-mesh-anchor in deep tunnel

The mechanical effects of bolt-mesh-anchor coupling support in deep tunnels were studied by using a numerical method, based on deep tunnel coupling supporting techniques and non-linear deformation mechanical theory of rock mass at great depths.It is shown that the potential of a rigid bolt support can be efficiently activated through the coupling effect between a bolt-net support and the surrounding rock.It is found that the accumulated plastic energy in the surrounding rock can be sufficiently transformed by the coupling effect of a bolt-mesh-tray support.The strength of the surrounding rock mass can be mobilized to control the deforma-tion of the surrounding rock by a pre-stress and time-space effect of the anchor support.The high stress transformation effect can be realized by the mechanical coupling effect of the bolt-mesh-anchor support, whereby the force of the support and deformation of the surrounding rock tends to become uniform, leading to a sustained stability of the tunnel.

An analytical model for nanowire junctionless SOI FinFETs with considering three-dimensional coupling effect

In this paper, the three-dimensional （3D） coupling effect is discussed for nanowire junctionless silicon-on-insulator （SOI） FinFETs. With fin width decreasing from 100 nm to 7 nm, the electric field induced by the lateral gates increases and therefore the influence of back gate on the threshold voltage weakens. For a narrow and tall fin, the lateral gates mainly control the channel and therefore the effect of back gate decreases. A simple two-dimensional （2D） potential model is proposed for the subthreshold region of junctionless SO1 FinFET. TCAD simulations validate our model. It can be used to extract the threshold voltage and doping concentration. In addition, the tuning of back gate on the threshold voltage can be predicted.

Coupling Effect of Water and Fertilizer on Soybean Yield and Nutrient Absorption

Soybean cultivar Bei 92-28 was tested in this experiment in 2000 to study the coupling effect of water and ferilizer on soybean yield.The results showed that the effect of irrigation varied among the levels of fertilizer application,and vice versa;pods per plant,seeds per pod.and 100-seed weight had positive correlations with soybean yield,but the degrees of correlations of different treatments were various;LAI and dry matter accumulation could be significantly increased when watered and applied fertilizer with different levels,but high fertilizer application treatment didn't obtain the highest yield;watering could increase the absolute absorption amount of N,P,K in seeds,but the accumulation rates were various.

Mechanical behaviours of bedded sandstone under hydromechanical coupling

The combination of the dipping effect and hydromechanical(H-M)coupling effect can easily lead to water inrush disasters in water-rich roadways with different dip angles in coal mines.Therefore,H-M coupling tests of bedded sandstones under identical osmotic pressure and various confining pressures were conducted.Then,the evolution curves of stress-strain,permeability and damage,macro-and mesoscopic failure characteristics were obtained.Subsequently,the mechanical behaviour was characterized,and finally the failure mechanism was revealed.The results showed that:(1)The failure of the sandstone with the bedding angle of 45°or 60°was the structure-dominant type,while that with the bedding angle of 0°,30°or 90°was the force-dominant type.(2)When the bedding angle was in the range of(0°,30°)or(45°,90°),the confining pressure played a dominant role in influencing the peak strength.However,withinβ∈(30°,45°),the bedding effect played a dominant role in the peak strength.(3)With the increase in bedding angle,the cohesion increased first,then decreased and finally increased,while the internal friction angle was the opposite.(4)When the bedding angle was 0°or 30°,the“water wedging”effect and the“bedding buckling”effect would lead to the forking or converging shear failure.When the bedding angle was 45°or 60°,the sliding friction effect would lead to the shear slipping failure.When the bedding angle was 90°,the combination of the“bedding buckling”effect and shear effect would lead to the mixed tension-shear failure.The above conclusions obtained are helpful for the prevention of water inrush disasters in water-rich roadways with different dips in coal mines.

In-situ coupling construction of interface bridge to enhance electrochemical stability of all solid-state lithium metal batteries

Polymer-based composite electrolytes composed of three-dimensional Li_(6.4)La_(3)Zr_(2)Al_(0.2)O_(12)(3D-LLZAO)have attracted increasing attention due to their continuous ion conduction and satisfactory mechanical properties.However,the organic/inorganic interface is incompatible,resulting in slow lithium-ion transport at the interface.Therefore,the compatibility of organic/inorganic interface is an urgent problem to be solved.Inspired by the concept of“gecko eaves”,polymer-based composite solid electrolytes with dense interface structures were designed.The bridging of organic/inorganic interfaces was established by introducing silane coupling agent(3-chloropropyl)trimethoxysilane(CTMS)into the PEO-3D-LLZAO(PL)electrolyte.The in-situ coupling reaction improves the interface affinity,strengthens the organic/inorganic interaction,reduces the interface resistance,and thus achieves an efficient interface ion transport network.The prepared PEO-3D-LLZAO-CTMS(PLC)electrolyte exhibits enhanced ionic conductivity of 6.04×10^(-4)S cm^(-1)and high ion migration number(0.61)at 60℃and broadens the electrochemical window(5.1 V).At the same time,the PLC electrolyte has good thermal stability and high mechanical properties.Moreover,the Li Fe PO_(4)|PLC|Li battery has excellent rate performance and cycling stability with a capacity decay rate of 2.2%after 100 cycles at 60℃and 0.1 C.These advantages of PLC membranes indicate that this design approach is indeed practical,and the in-situ coupling method provides a new approach to address interface compatibility issues.

Study on Rigid-Flexible Coupling Effects of Floating Offshore Wind Turbines

In order to account for rigid-flexible coupling effects of floating offshore wind turbines, a nonlinear rigid-flexible coupled dynamic model is proposed in this paper. The proposed nonlinear coupled model takes the higher-order axial displacements into account, which are usually neglected in the conventional linear dynamic model. Subsequently,investigations on the dynamic differences between the proposed nonlinear dynamic model and the linear one are conducted. The results demonstrate that the stiffness of the turbine blades in the proposed nonlinear dynamic model increases with larger overall motions but that in the linear dynamic model declines with larger overall motions.Deformation of the blades in the nonlinear dynamic model is more reasonable than that in the linear model as well.Additionally, more distinct coupling effects are observed in the proposed nonlinear model than those in the linear model. Finally, it shows that the aerodynamic loads, the structural loads and global dynamic responses of floating offshore wind turbines using the nonlinear dynamic model are slightly smaller than those using the linear dynamic model. In summary, compared with the conventional linear dynamic model, the proposed nonlinear coupling dynamic model is a higher-order dynamic model in consideration of the rigid-flexible coupling effects of floating offshore wind turbines, and accord more perfectly with the engineering facts.

Coupling effect of evaporation and condensation processes of organic Rankine cycle for geothermal power generation improvement

Organic Rankine cycle(ORC)is widely used for the low grade geothermal power generation.However,a large amount of irreversible loss results in poor technical and economic performance due to its poor matching between the heat source/sink and the working medium in the condenser and the evaporator.The condensing temperature,cooling water temperature difference and pinch point temperature difference are often fixed according to engineering experience.In order to optimize the ORC system comprehensively,the coupling effect of evaporation and condensation process was proposed in this paper.Based on the laws of thermodynamics,the energy analysis,exergy analysis and entropy analysis were adopted to investigate the ORC performance including net output power,thermal efficiency,exergy efficiency,thermal conductivity,irreversible loss,etc.,using geothermal water at a temperature of 120℃as the heat source and isobutane as the working fluid.The results show that there exists a pair of optimal evaporating temperature and condensing temperatures to maximize the system performance.The net power output and the system comprehensive performance achieve their highest values at the same evaporating temperature,but the system comprehensive performance corresponds to a lower condensing temperature than the net power output.

Concrete Damage and Neutralization under Coupling Effect of Carbonation and Freeze-thaw Cycles

Simulating the coupling effect brought by freeze-thaw and carbonation environment, we experimentally investigated concrete durability, the variation characteristics of both concrete dynamic elastic modulus, and its neutralization depth. The influences imposed by carbonation on the freeze-thaw damage of concrete was studied as well and vise versa so as to shed light on the influencing mechanism together with the mutual interaction between them. The experimental results show that the damage caused by the coupling effect of freeze-thaw and carbonation on concrete is severer than any single effect of them two could bring. This provides certain theoretical references and paves down foundations for the further study in concrete durability related by the coupling environmental effect.

Characteristics of anomalous Hall effect in spin-polarized two-dimensional electron gases in the presence of both intrinsic,extrinsic,and external electric-field induced spin-orbit couplings

The various competing contributions to the anomalous Hall effect in spin-polarized two-dimensional electron gases in the presence of both intrinsic, extrinsic and external electric-field induced spin-orbit coupling were investigated theoretically. Based on a unified semiclassical theoretical approach, it is shown that the total anomalous Hall conductivity can be expressed as the sum of three distinct contributions in the presence of these competing spin-orbit interactions, namely an intrinsic contribution determined by the Berry curvature in the momentum space, an extrinsic contribution determined by the modified Bloch band group velocity and an extrinsic contribution determined by spin-orbit-dependent impurity scattering. The characteristics of these competing contributions are discussed in detail in the paper.

In Situ Coupling of Highly Dispersed Ni/Fe Metal-NC Sites and N-Doped 3D Carbon Fibers Toward Free-Standing Bifunctional Cathode for Flexible Zinc-Air Battery

Designing flexible free-standing air-electrode with efficient OER/ORR performance is of vital importance for the application of Zinc-air batteries in flexible electronics.Herein,a flexible free-standing electrode(Ni/Fe-NC/NCF/CC)is synthesized by in-situ coupling of binary Ni/Fe-NC nanocubes and N-doped carbon nanofibers(NCF)rooted on carbon cloth.The highly dispersed binary Ni/Fe-NC sites ensure excellent ORR activity and create efficient OER active sites relative to Ni-NC and Fe-NC.The in-situ coupling of Ni/Fe-NC and NCF constructs a 3D interconnected network structure that not only provides abundant and stabilized reactive sites but also guarantees fast electron transfer and gas transportation,thus achieving efficient and fast operation of ORR/OER.Therefore,Ni/Fe-NC/NCF/CC displays a much positive potential(0.952 V)at 4.0 mA cm^(-2)for ORR and a low OER overpotential(310 mV)at 50 mA cm^(-2).The Zinc-air battery with Ni/Fe-NC/NCF/CC air-electrode exhibits excellent battery performance with outstanding discharge/charge durability for 2150 cycles.The flexible Zn-air batteries with foldable mechanical properties display a high power density of 105.0 mW cm^(-2).This work widened the way to prepare flexible bifunctional air-electrode by designing composition/structure and in-situ coupling.

Upper Bound Solution of Soil Slope Stability under Coupling Effect of Rainfall and Earthquake

Based on the limit analysis upper bound method,a new model of soil slope collapse has been proposed which consists of two rigid block zones and a plastic shear zone.Soil slope was induced failure by coupling effect of rainfall and earthquake,and these blocks were also incorporated horizontal earthquake force and vertical gravitate.The velocities and forces were analyzed in three blocks,and the expression of velocity discontinuities was obtained by the principle of incompressibility.The external force work for the blocks,the internal energy of the plastic shear zone and the velocity discontinuous were solved.The present stability ratios are compared to the prevenient research,which shows the superiority of the mechanism and rationality of the analysis.The critical height of the soil slope can provide theoretical basis for slope support and design.

Finite size effects on helical edge states in HgTe quantum wells with the spin orbit coupling due to bulk- and structure-inversion asymmetries

There is a quantum spin Hall state in the inverted HgTe quantum well, characterized by the topologically protected gapless helical edge states lying within the bulk gap. It has been found that for a strip of finite width, the edge states on the two sides can couple together to produce a gap in the spectrum. The phenomenon is called the finite size effect in quantum spin Hall systems. In this paper, we investigate the effects of the spin-orbit coupling due to bulk- and structure-inversion asymmetries on the finite size effect in the HgTe quantum well by means of the numerical diagonalization method. When the bulk-inversion asymmetry is taken into account, it is shown that the energy gap Eg of the edge states due to the finite size effect features an oscillating exponential decay as a function of the strip width of the HgTe quantum well. The origin of this oscillatory pattern on the exponential decay is explained. Furthermore, if the bulk- and structure-inversion asymmetries are considered simultaneously, the structure-inversion asymmetry will induce a shift of the energy gap Eg closing point. Finally, based on the roles of the bulk- and structure-inversion asymmetries on the finite size effects, a way to realize the quantum spin Hall field effect transistor is proposed.