Abstract:To promote the use of recycled concrete in practical engineering,pull-out tests were carried out to study the influence of Coarse/Fine Recycled Concrete Aggregate(CRCA/FRCA) replacement rate,water-cement ratio and the anchoring conditions on the compressive strength and bonding properties of Recycled Aggregate Concrete(RAC).The results show that: the bond strength of RAC rises with the increasing of CRCA replacement rate,and arrives at the maximum when the rate= 60%,then reduces;the bond strength of RAC reduces while the FRCA replacement rate increases,and it is better than that of ordinary concrete;too much CRCA/FRCA replacement will reduce the compressive strength of RAC;lower water-cement ratio can improve the compressive strength and bond strength of RAC,and water-cement ratio variation has less influence on RAC than that of ordinary concrete;appropriate increase in the thickness of concrete cover(≤3 d) and the anchorage length can increase the bond strength of RAC.In addition,by concerning the relationship between the bond strength of RAC and CRCA/FRCA replacement rate,water-cement ratio,compressive strength,anchorage length,a formula was established.

Abstract:To reveal the actual working state of loading system in real-time substructure testing(RSTing),and based on the existing transfer function model of servo-hydraulic system developed by Jung,three modifications had been made,which included transfer function of actuator、servo-valve gain and pressure feedback gain.A new numerical model of servo-electric hydraulic system was set up and used to simulate the effects of the dynamics of the test system.The simulation results agree very well with those of simulink model,which verifies the correctness of the modifications to the existing transfer function model.

Abstract:For the reason that the research on outer-jacketing mega frame for storey-adding’ collapse and design method that considering construction lags behind that of practice,outer-jacketing mega frames for storey-adding in Site-class I-III,design seismic group 1st-3rd,seismic fortification intensity 7-8 were analyzed and the collapse mechanism was studied by elasto-plastic analyze program IDARC2D.It reveals that the design of bottom frame is the key point to make the structure damaged with beam-hinge mechanism.Measures to avoid collapse of structure by enhance the grade suitably were put forwarded.Construction technical measures were refined according to construction practice,design method was presented based on the elasto-plastic analysis results,that provide preference for the design of outer-jacketing mega frame for storey-adding.

Abstract:In order to promote the engineering application of the channels with inclined simple edge stiffeners and definite the difference between it and lipped channels,a total of 70 examples with seven stiffener inclined angles and ten different eccentricities under eccentric compression loading acted in the plane of axis of symmetry were selected to be studied by nonlinear finite element analysis using program ANSYS.Effects of the above parameters on stability capacity,buckling modes and deflection behavior of channels with inclined simple edge stiffeners under eccentric compression loading were investigated.The result shows that the stability capacity and buckling modes are notably affected by eccentricity.No member got the maximum carrying capacity at zero-eccentricity.At the same negative eccentricity,the carrying capacity of member gradually reduced with the stiffener inclined angles increasing,but little differences among the carrying capacities could be observed when the stiffener inclined angle is an obtuse angle,which doesn’t affect the carrying capacity anymore.The earlier distortional buckling occurred,the lower carrying capacity of member would be obtained under the positive eccentric compression loading.

Abstract:The relationship between cyclops and microcystis aeruginosa had been studied.The static test was divided into 5 groups in concordance with different proportion of populations and studied with periods of 13 days.The way of counting includes micro-metering and numbering.The results show that when the cyclops density is 100/L and the microcystis aeruginosa density is 108/mL,they inhibite each other strikingly.When the microcystis aeruginosa density is reduced to 107/mL,their inhibitory action is also obvious.And then if the cyclops density is reduced to 50/L,the inhibitory action becomes undistinguishable.So there is a proportional relationship between the inhibition intensity and their density.This study provides a new idea and theoretical basis for water bloom and cyclops overpopulated.

Abstract:To study microbial community dynamics and population stability on the bioenhancement activated carbon(BEAC),the samples were taken from different position of the carbon column at different operation time.The Genomic DNA of the microbes on the activated carbon was released by breaking the bacterial cells.After purification of the genomic DNA,the V3 region of genomic 16S rDNA was amplified by using specific primers(F357-GC and R518).The polymerase chain reaction(PCR)products were about 250 bp and then separated by parallel denaturing gradient gel electrophoresis(DGGE).The profile of DGGE showed that the structure,categories and number of microbial community were changing dynamically during running of the reactor.The categories and number of the inbreaking bacteria were reducing continuously.5 artificial enhanced and immobilized bacteria were existing all through and distributed differently in the carbon column.Further more,they became dominant community after dynamic succession and community structure tended to be stable.The stability of the immobilized bacteria ensured the stability of operation and removal effect of BEAC procedure.

Abstract:To investigate the removal efficiency of nitrosodimethylamine(NDMA) from water by zero-valent zinc,reduction experiments of trace concentration of NDMA by zero-valent zinc were carried out,and the effects of the initial amount of zinc,initial concentration of NDMA,dissolved oxygen concentration,solution pH,temperature on the reduction of NDMA were studied.With the initial amount of 10 g·L-1 zinc,the removal efficiency of NDMA could reach to above 99% at the reaction time of 14 h.The effect of dissolved oxygen and initial NDMA concentration on the reduction of NDMA are not remarkable while the pH and the temperature of solution could influence the reduction of NDMA by zinc greatly.The smaller the pH is or the higher the temperature is,the higher the removal rate of NDMA is.

Abstract:To control the formation of bromate in the treatment of drinking water with bromide by ozone,the influencing factors on bromate formation were studied in detail.Results of pilot test and pilot scale test show that,most of bromate are generated in the first 10 minutes of ozonation,;and when pH>8,the bromate formation is increased evidently;when pH<7,the bromate formation is limited under 10 μg/L.The existence of and NOM could inhibit the generation of bromate.When the concentration of NOM gets to 40 mg/L,the amount of bromate will be under 10 μg/L.

Abstract:To find a new effective method of degradation of atrazine,the degradation was studied by electrocatalytic oxidation of atrazine in water,and Sb doped Ti/SnO2 electrode was used as anode and stainless steel plate as cathode.The main influencing factors and degradation pathway of atrazine were discussed.Results showed that when current density was 200 A/m2,initial concentration of atrazine was 10 mg/L and pH value was 6.97,100% atrazine was removed within 30 min.Meanwhile,power consumption was only 6.67×10-2 kWh/g.The primary degradation process is dealkylation,dechlorinationa and alkylic-oxidation,and a series of intermediate products such as OHA,DAA,ANE were produced during the process of electrocatalytic oxidation of atrazine.The results suggest that electrocatalytic oxidation method can be cost-effective removal atrazine.

Abstract:For better understanding the characteristics of adsorption of benzene on activated carbone,Analysis the physical and chemical characteristics of two kinds of carbon,the micro-surface area of coal carbon is 320 m2/g,which is far less than that of woody carbon that is 563 m2/g.The chemical groups on the surface of coal carbon is abundant than that on woody carbon.The qualitative analysis of the adsorption of water molecule on two kinds of carbon is conducted by Dubinin and Sperpinsky equation(DS),the results show that,the coal carbon is prone to adsorb water molecule while the woody carbon is tend to adsorb benzene;Using four isotherm equations(Langmuir、Freundlich、Sips、Toth) to simulate the experimental data,the results show that the relativity coefficient(R2) of the Toth equation is more close to 1,and it best fits the adsorption of benzene from water;compare the parameters of thermodynamic of the adsorption of benzene on two kinds of carbons,the results indicate that differences of Gibbs free energy(-ΔG0),enthalpy(ΔH0) and entropy(ΔS0) of woody carbon are larger than that of coal carbon,which indicate that the woody carbon is more adaptable to adsorb benzene from water.

Abstract:To understand the property of chlorobenzene adsorption on powder activated carbon(PAC),an analysis of physical characteristics and pore size distributions(PSD) was conducted for the four types of PAC which were used in the kinetic study of chlorobenzene adsorption from liquid solution.It was concluded that all the four types of PAC had a wild pore size distribution,and the adsorption capability increased with the increasing of BET surface area and pore volume.The rate of chlorobenzene adsorption onto PAC was so fast that the adsorption capability at 5 minutes was more than 80 percent of that of adsorption equilibrium achieved at about 30 minutes.The experimental adsorption data showed good correlation with pseudo-second-order kinetics equation and pseudo-third-order kinetics equation which had a satisfied description for the process of chlorobenzene adsorption within 2 h and more than 2 h,respectively.

Abstract:To study the correlation between traditional water quality indexes and BDOC,the biological stability of drink water in a northern city water system was investigated and evaluated by BDOC.When the conentration of BDOC is between 0.11 mg/L and 0.40 mg/L,the water is in biological steady level.BDOC changed a few from the entry to the end in the network.Among traditional water quality indexes,turbidity presents a positive correlation with BDOC,while pH shows a negative correlation.The charges of BDOC and residual chlorine should be combined together to control bacteria re-growth in the network,not merely depending on the biological index.

Abstract:In this study,phosphorus accumulating organisms(PAOs) were cultivated in two SBR systems,one operated as anaerobic/aerobic mode,the other as anaerobic/anoxic mode.The effects of nitrite on the two modes of phosphorus removal system were investigated.The results showed that presence of nitrite inhibits both aerobic and anoxic phosphorus uptake,but aerobic phosphorus uptake was more affected than anoxic phosphorus uptake.In this research,0.88 mg/gVSS and 6.72 mg/gVSS were observed as threshold for aerobic and anoxic phosphate uptake,respectively.With the aid of a stepwise elevation of NO2——N added in influent,denitrifying phosphorus accumulating organisms were gradually accommodated to resist and utilize NO2——N as electron acceptor,but the phosphorus removal efficiency was lower than O2 and NO3——N as electron acceptors.

Abstract:An FPGA based all-digital close-loop angle tracking algorithm is proposed to achieve an all-digital resolver-digital converter(RDC) with low cost and high integration.ΔΣ modulation technology is introduced into sine reference signal generator,to simplify hardware filtering circuit and minimize the damping and phase lag.Optimized control of sampling and filter processing are applied to guarantee favorable acquisition of sine and cosine feedback signals under harsh EMI environment.A PLL-based angle tracking observer is designed,which uses CORDIC arithmetic for phase detection and PI regulator for rapid close-loop tracking.ΔΣ modulator,time sequence controller,CORDIC phase detector,and PI regulator IP cores are written in Verilog HDL and have been tested on Xilinx XC3S400 FPGA.Experimental results verify that the all-digital RDC can make digital conversion with high precision,high dynamic and static characteristics,relying on rapid parallel algorithm of FPGA without much cost increase.

Abstract:Silicon/graphite/carbon composite was prepared by high temperature pyrolysis and used as the anode of Li-ion battery.The structure and electrochemical properties were characterized by X-ray diffraction(XRD),cyclic voltammetry(CV) and constant current charge-discharge methods.Also,the effects of heating treatment and different binder on electrochemical cycleability were studied,and the results showed that both of the aqueous binder and heating treatment could improve the electrochemical properties and the cycle stability.The optimized anode delivered initial reversible capacity of 970.5 mAh/g and remained 822.1 mAh/g after 40 cycles,which demonstrated high cycle stability.

Abstract:To investigate the property and function of endoglucanse(EGⅠ),the transcriptional expression of egⅠ of Trichoderma viride T4 was analyzed by Northern blot during its growth and development in medium with different carbon source.The full length cDNA sequence of egⅠwas obtained by RT-PCR method and the recombinant vector pYES2-egⅠ was constructed.The vector was transformed into Saccharomyces cerevisiae INVSc1 and H158.The results indicated that the egI was expressed strongly when T.viride T4 was grown in liquid medium containing cellulose as carbon source.The expression of egI was the highest in corn stalk medium,and cellobiose also induced the expression of egI,but no signal was detected in glucose or fructose medium.The ORF of egI was 1 377 bp encoding a protein of 459 amino acids and belonged to glycosyl hydrolase family 7 having cellulose binding-domain and catalytic-domain.egI was a kind of secreted protein because there was signal peptide in the amino acid sequence.The egI transcription of transformants reached highest at 48 hours and a peak recombinant enzyme activity was 0.081 6 U/mL at 60 hours,the recombinant enzyme of EG I of INVSc1 improved 32.5% than that of H158.

Abstract:Lithium metal electrode was pre-treated with 1,3-dioxolane in order to study the surface modification mechanism on it,then coin cells were assembled with LiCoO2 cathode and the cycle and discharge performance were tested.The electrochemical impedance spectroscopy(EIS) were employed on the cells in the 10th and 70th cycle at different discharge voltage,and a reasonable equivalent circuit was proposed to analyze the changement of impedance values correspondingly.It is found that the electrode properties are improved greatly.The EIS analysis shows that 1,3-dioxolane can form a stable SEI layer on the surface of Li electrode.This layer is able to enhance the interfacial compatibility without depressing Li ions kinetic behavior.The reason for the performance of lithium electrode getting worse in cycleability is the increment of surface membrane resistance and charge transfer resistance,which leads to the higher lithium ions migration resistance and electron transfer resistance.

Abstract:To obtain industrial yeast strains with antioxidant activity,identification of two yeasts with excellent antioxidant activity,which were isolated from raw milk,were carried out in this paper.Based on their morphological,biochemical,physiological and genotypic characterization,two strains were identified as Pichia fermentans.Then,the influence of these two strains on the main components in the milk was further evaluated by incubating in ultra high temperature(UHT)-processed bovine milk.The results indicated that both of these two strains were able to produce ethanol and facilitate proteolysis and lipolysis,and increased the content of free amino acid and fatty acid in the UHT milk.

Abstract:To analyze the influence of machining deflection error on contact specialties of the orthogonal face gear drive,the coordinates of the points contact orthogonal face gear drive is built up and the contact points equations are deduced.Based on these equations,the change of tooth shape,the contact point position,and the maximum press stresses on the orthogonal face gear are analyzed.According to the solution method of the principal curvatures,the influence on the principal curvatures at the contact points is also analyzed,and by the solution method of the problem of Boussinesq,the contact specialties equations are developed.Results show that the contact specialties of the orthogonal face gear are not sensitive to the machining deflection error.

Abstract:To improve the performance of electrostatically actuated valveless micropump,simulation of its dynimic characteristics have been conducted by full electrostatic-mechanic-fluidic coupled model(CFM) and prescribed deformations model(PDM)respectively.By comparing the calculated results of diaphragm deflections,transient variations of central displacements,chamber pressures and flow rate of inlet/outlet,it can be concluded that the PDM has lower cost and inadequate precision,but some distorting dynamic characteristics may be resulted from;The FCM can predict the transient behaviors of the micropump quite well since the effects of electro-mechanical coupling and fluid-structural interaction have been considered,but the computation cost is much more expensive.

Abstract:To seek an effective aerodynamic measure to control the vortex induced vibrations(VIV) of a box girder with projecting slab(BGPS),VIV of a 1∶50 scale sectional model with 10 cases were tested in TJ-1wind tunnel based on a cable-stayed bridge with composite box girder.The aerodynamic measures whose mitigation efficiencies were studied included moving the rails of tool car,installing guide vanes with different forms and installing spoilers with different forms.The research results show that VIV amplitudes of BGPS increase with the increasing of wind attack angle,so VIV performance is sensitive to wind attack angle.As for the guide vanes,they may raise VIV amplitude of BGPS,and the included angle and the width of horizontal board are key factors to affect mitigation efficiency of them,concretely,the bigger the included angle is and the wider the horizontal board is,the better the mitigation efficiency is.After the guide vanes are installed on BGPS,the rails of tool car have little effect on VIV performance of BGPS,so the mitigation efficiency of moving the rails of tool car is negligible.As for the spoilers,they can control VIV of BGPS efficiently,and the wider the spoilers are,the better the mitigation efficiency is,but the mitigation efficiency of the spoilers is correlative to wind attack angle closely.

Abstract:To reveal the weakness of structural system by studying structural performance susceptibility to local damage,a method of structural vulnerability analysis based on the plastic limit theory is proposed,and based on the mechanism generation method,the ultimate loading factor and the corresponding failure mode of a truss structural system are analyzed.The ultimate loading factor is then used to measure the performance of the structural system.By contrasting different damage scenarios under specified structural performance requirement,the most vulnerable damage scenario can be obtained according to the variation of ultimate loading factor to the severity of damage.The results of the case study show that the structural performance degenerates with the damage severity,and the dominative failure mode also changes with the damage severity due to the variation of structural topology composition and the redistribution of structural internal force.All the components related to a certain failure mode are the key components which serve as the most influential part to the structural performance.Therefore the analytical results can be as a reference for the structural design,monitoring and maintenance.

Abstract:To study the relationship between ultimate strength of post-installed rebar and fire duration,4 specimens in fire were designed and tested.The test procedure included specimen installation,heating by oil burner and testing when the heating time reached to the fixed time.Records had been made on the temperature,the ultimate strength,the rebar displacement and the heating time.The test results show that when the fire duration is less than 30 min,the ultimate strength of 15d have great difference from that of 20d.While the fire duration is more than 45 min,the ultimate strengths of 15d and 20d have little difference from each other.When the fire duration is more than 60 min,the ultimate strength at high temperature decreases about 85% of that at ambient temperature.The post-installed rebar can yield when the fire duration for 15d or 20d specimen is less than 15 min or 30 min,respectively.

Abstract:To study the failure mode and damage phenomenon of fire retardant coating under monotonous and cyclic load,three experiments were carried out.The experimental results show that the bonding strength is weak between fire retardant coating and steel columns,especially under loaded.For the column monotonously loaded,on the flange with tension,initial cracks on the coating became serious and some new cracks arose.On the flange with compression,the initial cracks closed and the coating on the end of the column was broken down.For the column cyclically loaded,the bond between coating and columns failed more easily.Therefore,the fire retardant coating on steel columns is easily damaged under external force and the damage is serious at the bottom of column.The failure mode is breaking off and falling.The damage area has great relation with the load on top of the column.The coating on the web of column is integrated.

Abstract:A computational model is studied to analyze the mechanical performance of PC multi-girder structure,which includes the propagation of cracks within the beam and diaphragm,the cracking pattern,the distribution of transverse loads and the stress redistribution in the prestressed steels.In the study,the nonlinearity of concrete material is described by using smeared crack model and other corresponding criteria.According to the mechanical characteristics of PC multi-girder structure,two typical loadcases defined as symmetric loadcase and offset loadcase are designed and then the lateral mechanical performances are analyzed and clarified in detail.Numerical results testify that the computational model is correct and the occurrence of cracks is closely related with the disposal of the acted loads.When subjected to symmetric loads,the PC multi-girder structure firstly produces cracks in its diaphragm and then in its beam;under offset loads,the crack appears earlier in the beam than in the diaphragm.Cracks in the diaphragm weaken the transverse connections between the beams,which leads to unfavorable change of the transverse loads distribution.The stress in the prestressed bar increases slowly in the elastic stage and then fast until the yielding stress is reached.

Abstract:A simulative experiment was carried out for researching the influence of freeze-thaw cycles,chloride penetration,sulfate penetration and loading on the bearing capacity and deformation of the reinforcement members.The residual bearing capacity of normal section of bond strength,ductility and failure mechanism of loading-erosion beams,unloading-erosion beams and unloading-non-erosion beams was were discussed.The experimental results show that the coupling effect of loading and aggressive environment accelerate the degradation of mechanical properties and ductility of beams,and the higher the loading,the more the degradation.The failure forms of reinforcement concrete beam changes from ductile failure to brittle failure under the condition of 70%Fu loading.When to predict the bearing capacity and service life of reinforcement structure,the coupling effect of loading and aggressive environment should be concerned.The experimental results also show that the transverse crack is an influential factor for residual bearing capacity,so the durability of beams with transverse cracks and heavy load under the aggressive environment should be paid more attention.

Abstract:To obtain novel salt-tolerant phenol-degrading bacteria and amplify the corresponding genes,a bacterium named W1 was isolated from the active sludge samples.16S rRNA sequence analysis was used to identify the bacterium,and characteristics for phenol biodegradation were also studied.The 5’-and 3’-flanking regions of gene encoding the phenol hydroxylase were amplified from strain W1 by TAIL-PCR method.1wt%-10wt% was showed that strain W1 was identified as Arthrobacter sp.The strain was capable of growing in the medium with 1wt%-10wt% NaCl and utilizing phenol as the sole carbon and energy source.And it could also degrade some other aromatic compounds such as p-methylphenol,salicylic acid and p-hydroquinone,etc.When concentration of NaCl was about 5wt%,1 000 mg·L-1 phenol could be degraded more than 90% by strain W1.The complete gene cluster was about 6 kb,of which the gene encoding the large subunit of phenol hydroxylase exhibited the highest similarity about 93% with the corresponding gene of Alcaligenes sp.

Abstract:To eliminate the influence of uncertainty of parameter variations and load disturbance on the performance of the dynamical decoupling drive system of permanent magnet synchronous motors and based on disturbance suppression,a nonlinear decoupling control method is presented for the permanent magnet synchronous motors drive system.A state feedback controller is constructed based on Lyapunov function,which enables the system to be internally stable for all bounded interference and satisfies the arbitrarily small bounded L2 gain from interference input to its output.Simulation and experimental results show that the strategies improve the dynamic performance of the system greatly,and strengthen the robustness and anti-disturbance performance.

Abstract:When directly buried pipes with large diameter,high temperature and pressure are installed by preheating,serious accidents such as pipeline rupture,compensator fracture will happen in cold water running or during the cooling process.Based on "Average Stress Temperature",preheating temperature is proposed and its function formula is set up on the condition that the heating compressive stress is equivalent to the cooling tensile stress.The curve of "Average Stress Temperature" changed with pressure and diameter is drawn,which can be used to analyze pipeline accidents.Results show that high preheating temperature of large diameter pipes is the main reason for fracture during cooling.When calculating preheating temperature,not only the minimum and maximum cycle temperature,but also the pressure,the diameter and the wall thickness and so on should be considered.The increase of pipeline pressure and diameter plays an important role in reducing "Average Stress Temperature",but has nothing to do with"Intercycle temperature".When all preheating parameters are calculated by using "Average Stress Temperature" instead of "Intercycle temperature",cooling tensile stress for preheated directly buried pipes can be reduced evidently.

Abstract:To know the law of nuclide transport in fractured media,the basic differential equations of nuclide transport in fracture and matrix were obtained,which were coupled at the interface between the fracture and matrix,and the general analytic solutions of nuclide transport in single fractured media with exponential attenuation source in fracture were deduced by Laplace transform.Moreover,the transport of Th-229,Cs-135 and Se-79 were simulated with the analytic solutions,and the relative concentration of these nuclide in fracture and matrix were predicted.These simulation results show that the analytic solutions can be used to solve the problems of nuclide transport,groundwater contamination in fractured media,etc.

Abstract:In order to judge whether a seawater-source heat pump district heating system(SSHPDHS) is really energy-saving than the conventional boiler-house district heating system(BHDHS),the expression of the critical COP value of the heat pump unit for energy-saving in the SSHPDHS is derived in the paper.Three main factors affecting the energy efficiency of the SSHPDHS are concluded by comparing the energy consumption of the two systems.These factors are the boiler house heating efficiency,the heating district radius and the design parameters of the seawater pump,which are discussed in the context of actual projects.The critical COP value of the heat pump unit for energy-saving is effective on the energy efficiency judgement between the two systems.Also a method to improve the energy efficiency of the SSHPDHS for the system designers is presented here.

Abstract:To quantitatively analyze the effect of debonding between steel tube and filled concrete on the ultimate bearing capacity of CFST arch bridge,a calculation model was proposed based on reasonable assumptions.The calculation program was written by using finite element method,and used to simulate the process of debonding between steel tube and filled concrete.The program was verified.By taking a single tube CFST arch bridge as a case study,the calculation results show that under uniformly distributed load on full span,the complete debonding makes the ultimate bearing capacity of single tube CFST arch bridge decreased about 10%.

Abstract:To improve the seismic performance of RC frame structure under strong earthquake,the effectiveness of the provisions to ensure the "strong-column-weak-beam" failure mechanism in current Chinese seismic design code is examined,and some effective measures to realize rational failure mechanism are studied.Based on the flexibility method on OPENSEE platform,the fiber model can be used to simulate the biaxial bending behavior of columns under variable axial load and the deterioration phase of the structural response.A 6-story regular frame structure located in each fortification intensity region was designed according to the current seismic design code and studied using the nonlinear pushover analysis to investigate the failure mechanism of the structure.The analysis results were compared with the actual structural damage phenomena observed in Wenchuan Earthquake.The minimum requirement of ensuring the plastic hinge formation mostly in beams was discussed.The analysis results indicated that few plastic hinges were developed in the frame structure in the region of seismic fortification intensity 6.In seismic fortification region 7 and 8,plastic hinges were mainly formed in columns and lateral drift mechanism was developed,leading to inadequate seismic resistance of the structure.The plastic hinge formation mostly in beams was only realized in the frame structure located in seismic fortification region 9.It is proposed that increasing the strong column-weak beam coefficient,reducing the axial load ratio and increasing the design seismic force for small earthquake can help realize the expected failure mechanism that plastic hinges are mainly formed in beams.

Abstract:With plate capacitor theory and calculus method,the capacitance of micro electro-mechanical system(MEMS) electrostatic comb actuator is studied.Considering the affections of fabrication technology and edge effect,a calculating model is built,by which the calculations for the fabricated comb actuator are carried out under the ideal condition and the condition of considering border effect and fabricating technology.The calculated results are 1.267 3 pF and 1.440 3 pF respectively,of which the relative errors with the high precision LCR device measured value 1.517 2 pF are 16.47% and 5.07%.This indicates that the model can be used to get higher precision,if the border effect and fabrication process are taken into account.

Abstract:For the purpose of providing theoretical foundation for the optimization and selection of pneumatic boost regulator,and considering of the working process of pneumatic boosting regulator,piston friction,air heat exchange and other factors non-linear differential equations were set up by using first law of thermodynamics,gas state equation,continuity equation,energy equation and momentum equation,and by MATLAB/simulink,the variation of pressure and the flow of air in boosting chambers and driving chambers were obtained.According to the principle of simulation,pneumatic regulator was studied experimentally,and the curves of exhaust flow and pressure of air in tank were got.The simulation results are in good agreement with the experimental results,which show that the maximum air consumption and exhaust go down with the increase of boosting rate,and the air exhaust rate is about 50% while the efficiency is between 60%-70%.