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To explore the role of dislocation slip mode playing in the size effect of mechanical behavior of metallic materials, the tensile behavior of Cu-5at.%Mn and Cu-20at.%Mn alloys with thickness (t) spanning from 0.1 to 2.0 mm is investigated. The results reveal that the yield strength σYS of Cu-5at.%Mn alloy displays an independence of thickness, whereas the ultimate tensile strength σUTS and the uniform elongation δ show an obvious size effect. The σUTS and δ first slightly decrease as t is reduced from 2.0 to 0.5 mm, but evidently drop when t is below 0.5 mm. A similar size effect is also exhibited in Cu-20at.%Mn alloy; however, the variation trend of “the smaller the weaker” in size effect can be weakened by the planar slip of dislocations occurring during the deformation of this alloy.

The uniaxial tensile tests were conducted at different temperatures to explore the coupled influence of stacking fault energy (SFE) and short-range clustering (SRC) on the plastic deformation behavior of Cu-Ni alloys. The results demonstrate that the ultimate tensile strength and uniform elongation decrease with increasing temperature due to the competitive influence of SFE and SRC. Dynamic strain aging (DSA) effect is observed at 200 and 250°C, and such an effect becomes more notable with increasing Ni content. The occurrence of DSA effect is thought to be caused by pinning of moving dislocations by SRC and diffusing solute atoms. The plastic deformation mechanisms for Cu-Ni alloys is mainly governed by wavy slip of dislocations at different temperatures, since the SFE of Cu-Ni alloys are very high especially at high temperatures, and the effect of SRC can be nearly ignored.

Three-dimensional (3D) elastic-plastic finite element model (FEM) is adopted to research the effect of side groove on the crack-front J-integral for different size of Compact Tension (CT) specimens. Although the side-grooved CT specimen is widely used in the existing test method, such as ASTM E1820-13, the test data of fracture toughness is varying with the various geometric parameters. Before FE calculation, the material properties of Q345 steel were obtained by uniaxial tensile test, especially for the true stress-strain relationship. In this paper, it focuses on the numerical study of geometric parameter effects on the fracture toughness. Toward this end, the commercial FE software of ABAQUS is adopted to calculate the J-integral. Since the side groove of CT specimen is so important to make the fracture test success, the various parameters of side groove is intensively analyzed for obtaining the accurate J-integral along the crack front, including the effects of the angle, depth and root radius. In fact, the side groove effect is so significant around the crack front that cannot be ignored in the J-integral calculation. Through rigorous FE investigation, the influence of the side groove on the fracture toughness testing is fully disclosed, and the appropriate side groove configuration is recommended accordingly.

The interfacial reaction and growth of intermetallic compounds (IMCs) between the eutectic Sn-0.7 wt.% Cu solder and Cu substrate during soldering process were investigated experimentally. The Sn-0.7Cu/Cu couples were fabricated with soldering temperature varied at four levels of 300, 340 and 360°C. Microstructural analysis is conducted to analyze the IMCs thickness and morphology using scanning electron microscope. Two intermetallic phases were observed during soldering at the interface: η-phase (Cu6Sn5) and ε-phase (Cu3Sn) IMC layers, except for the solder joints which were fabricated at low temperature. The thickness of the η and ε IMC phases increase with increasing the soldering temperature. It’s found that the increase in total IMC layer thickness obeys a linear relationship with soldering temperature. And the relationship between X and T was given as X = 0.0866×T – 22.5 by means of linear fitting method.

This paper presents a new design scheme about the bearing transmission components based on compliant parallel spring mechanism, which is applied to small and medium scale impulse plate flowmeters. The detection components can be effectively carried with a more accurate trace of displacement in the horizontal direction. The mechanism design has advantages of no relative motion and friction between the structure components, and is well adapted over the traditional bearing components, based on the principle of compliant parallel spring mechanism. Thus, the measure precision of impulse plate flowmeter and working reliability are effectively improved. Firstly, the characteristics of displacement, strength and natural frequency are analyzed theoretically, and then the simulation of static strength, modal and fatigue are performed by the CAE software. The rationality and feasibility of this design scheme are further verified by the simulation results, which has certain guiding significance for the design of the actual product.

Through the application of electrochemistry, CO2 was captured in an eutectic mixture of Li-Na-K carbonates before forming a nanosized amorphous carbon powder. The carbon powder was used to study on the absorption on tetracycline in aqueous solutions. At 298K, the maximum adsorption capacity of tetracycline reached 127.76mg/g. The sorption data could be well fitted into pseudo-second-order kinetics and Frendlich sorption isotherms. The adsorption process was endothermic, spontaneous and irreversible.

Potentials of three plant species, rape, alfalfa and white clover, separately or jointly on the degradation of polycyclic aromatic hydrocarbons (PAHs) in soil were estimated by pots experiments. Results showed the presence of vegetation apparently enhanced the dissipation of PAHs at initial concentrations ranging from 20.05 to 322.06 mg·kg-1. Within 70-day experiment, alfalfa and white clover showed higher efficiencies for removal of PAHs than those of rape, and mixed cropping greatly enhanced the dissipation of PAHs as compared to single cropping. On average 74.87% of phenanthrene or 62.81% of pyrene were removed from soils with mixed cropping of rape and alfalfa, and 72.01% of phenanthren or 68.44% of pyrene removed by mixed cropping of rape and white clover. Results suggested a feasibility of the establishment of multispecies remediation for enforcing the dissipation of PAHs.

Although the traditional synchronous control system for the virtual shaft has met the accuracy requirements of most products, it still can not fully meet the requirements, for the high precision, high synchronization control. This article proposed multi-motor synchronous control strategy based on the relative coupling control combined with virtual main spindle control, and built simulation platform by Matlab/Simulink and simulated the strategy. The simulation result shows that the synchronous control strategy mentioned in this article can overcome synchronization error brought by external disturbance and parameter variation. Moreover, it will better achieve the multi-motor synchronous control compared with the traditional virtual shaft synchronization scheme

Phytoremediation of PAHs in soils at initial contents ranging from 20.05 to 322.06 mg·kg-1 was investigated under different planting patterns, and enhancement mechanisms were analyzed. Results showed that the dissipation of PAHs in soils growing white clover and alfalfa significantly exceeded those vegetating single species. During 70-day experiment, about 75.06% of Phe and 68.22% of Pyr was removed from the soils under mixed cropping; while only 31.8% and 64.03% of Phe and 27.84% and 51.93 of Pyr were removed under single white clover and alfalfa cropping, respectively. Of all pathways enforcing PAHs removal, the plant-microbial interactions is the most predominant. These results suggested a feasibility of the establishment of multi-species phytoremediation for improvement of the remediation efficiencies of PAHs, which may decrease accumulations of PAHs in crops and thus reduce their ecological risks.

Experimental method is applied to analysis the mechanical properties of super early-strength composite fiber concrete on high temperature. Specimen are heated to in the stove at different temperatures for 30 Minutes, then the axial compressive strength can be measured. The experimental results showed that: the high temperature mechanical properties of materials decreased significantly; compared to ordinary concrete specimen, the mechanical properties of super early-strength composite fiber concrete decline slower.

Super early-strength composite fiber concrete has been widely used. Seismic Performance of super early-strength composite fiber concrete columns needs to be known after high temperature, quasi-static tests under different high temperatures are experimented. The experiment showed that: the downtrend of hysteretic curves and skeleton curves are consistent, but reductions for both hysteretic curves and skeleton curves are diverse after different duration.

To conveniently find parking spaces for college staffs and visitors, the university parking query system is designed based on C/S architecture. By the design of automatically obtaining parking information based on image processing technology and the design of parking information inquiry, the system enables parking information exchange between Android mobile devices and Web server. It could improve the efficiency of parking spaces and also reduce the time spending on finding parking space.

Cavitation is a common harmful phenomenon in hydraulic transmission systems. It not only damages flow continuity and reduces medium physical performance, but also induces vibration and noise. At the same time, the efficiency of a system is reduced due to cavitation, especially dynamic performance are deteriorated. Applying commercial CFD software FLUENT, the cavitation issuing from the orifice was numerically investigated, reducing the harm. The effect of liquid parameters (such as surface tension, gas content, and the temperature) on the oscillation of bubble is studied numerically. The modified Rayleigh-Plesset equations are presented to describe the oscillation of bubble in different liquids. Employing the finite difference calculus, the behavior of a cavitation bubble in liquids with different physics parameters are obtained. Meanwhile, the numerical results are compared with experiment results. It is observed that the viscous force decreases the growth and collapse of a bubble, making it expand or collapse less violently. And the surface-tension forces stave bubble growth progress and speed up bubble collapse process. On the other hand, both the maximum bubble radius and bubble lifetime increase with increasing temperature. These results can provide theory basis for understanding cavitation bubble dynamics in the hydraulic systems.

This paper presents an investigation of argon capacitively coupled plasma at low pressure. A two-dimensional, time-dependent fluid model is used to describe the production, transport, and destruction of electrons and positive ions. The model is solved for a GEC(gaseous electronics conference) Cell reactor type (with 4cm diameter and 2.5cm interelectrode distance) operating at frequency 13.56MHz, pressure 1Torr and applied voltage 1000V, in pure argon. Two-dimensional distributions are presented in the stationary state, including electron temperature and species density i.e. electron, ion and metastable atom. The electric field and electric potential at different phases in one RF cycle is also studied.

We used gas chromatography mass spectrometry to analyze characteristics of air pollution caused by MTBE in Beijing. The results showed that the atmospheric concentration of MTBE divided by function was: cultural tourism zone > industrial zone > commercial and residential zone > background point. Divided by time, in general, evening (17:00-19:00) > midnight (23:00-24:00) > noon (11:00-13:00); divided according to the day, in general, weekend > workday, but industrial zone is contrary. Traffic volume and traffic conditions are important factors in Beijing’s air pollution of MTBE. Production processes and environmentally friendly measures of industrial zone will also have some impacts on it. In the evening (17:00-19:00) and at weekend, concentration of MTBE in the atmosphere was comparably large.

Magnesium hydroxide was prepared through direct precipitation using magnesium chloride and ammonia as raw materials. In this paper, we mainly studied the effects of magnesium hydroxide on product characterization when the concentration of raw materials was changed. The products were characterized through laser light particle size analysis, scan electron microscope and X-ray diffraction. The study showed that a sudden change in the morphology of magnesium hydroxide products and in the polarity of the crystal occurred under the following conditions: stirring speed of 2500 rpm, reaction temperature of 60°C, ammonia to magnesium chloride ratio of 2:1, ammonia addition rate of 20 mL/min, and aging time of 30 min. As the raw material concentration was changed, the morphology of magnesium hydroxide products and the polarity of the crystal exhibited sudden change. When the concentration of magnesium chloride was changed to 0.8 mol/L, the product demonstrated a flower-like globular structure, the largest size, and the minimum polarity. When the concentration of magnesium chloride was more than 1 mol/L, the product exhibited a flake structure, no obvious aggregation and a narrow particle size distribution.

Potentials of three plant species, rape, alfalfa and white clover, separately or jointly on the degradation of polycyclic aromatic hydrocarbons (PAHs) in soil were estimated by pots experiments. Results showed the presence of vegetation apparently enhanced the dissipation of PAHs at initial concentrations ranging from 20.05 to 322.06 mg·kg-1. Within 70-day experiment, alfalfa and white clover showed higher efficiencies for removal of PAHs than those of rape, and mixed cropping greatly enhanced the dissipation of PAHs as compared to single cropping. On average 74.87% of phenanthrene or 62.81% of pyrene were removed from soils with mixed cropping of rape and alfalfa, and 72.01% of phenanthren or 68.44% of pyrene removed by mixed cropping of rape and white clover. Results suggested a feasibility of the establishment of multispecies remediation for enforcing the dissipation of PAHs.

The concentration and distribution features of MTBE in the atmosphere in Shenzhen were studied by analyzing samples which were collected in three consecutive days. In this study, pre-concentrator technology and gas chromatography were used. The result showed that the MTBE could was detected in atmosphere of the Shenzhen, and the range of its concentration was from 0.086 - 1.453μgm-3, including the daily average concentration of 0.662±0.334μgm-3 in industrial area, 0.331±0.216μgm-3 in commercial residential area, 0.258±0.154μgm-3 in tourist area, and 0.158±0.045μgm-3 in background area. The MTBE concentration in industrial area was 2 times of the commercial residential area, 2.6 times of tourist area and 7 times of the background area. These differences were statistically significant (p-3. However, the MTBE concentration in the commercial residential area and tourist area were highest in the period of 11:00-13:00, the MTBE concentration were 0.394±0.224μgm-3 and 0.446±0.069μgm-3 respectively. In the workday, the industrial area and commercial residential area were higher compared to the weekend, and the tourist area showed opposite trends, but no matter the comparison of hour average concentration or the workday and weekend, the difference were not statistically significant. It was concluded that the MTBE concentration in atmosphere environment in Shenzhen has the typical spatial specificity because of the different source of MTBE, but has no the time specificity.

Modified polyurethane fiber was prepared by wet spinning method, Different amount of chitosan powder that dissolving in polyurethane solution to get spinning solution were examined. This materials presents excellent adsorption capacity on Pb2+. the absorption type on Pb2+ of this modified fibers was monomolecular. The modified fibers get the maximum adsorption 25.53mg/g when the quality ratio of chitosan and polyurethane was 1:1 under the condition of 30°C and pH 6.

Crash Reduction Factor (CRF) is an important indicator for Economy Analysis of Safeguard Technology. This paper introduces the concept of CRF, and pointed out the limitations of its application. Meanwhile, it is necessary to adopt a variety of safeguard measures for multiple accident potential on a secton of highway in domestic mountainous rural road. Therefore, this paper presents the concept of general CRF. Then, multiple-event probability formula is proposed to calculate the generalized CRF for the feature of CRF. Finally. At last, discussed the work we needed to do if CRF was to be introduced into China.

The blast impact dynamic experiment of reinforced concrete rectangular plate with simply supported boundary conditions was performed using explosion pressure simulator. With 3-D FEM software LS-DYNA, the separate solid models of concrete and steel were established and 3-D FEM dynamic analysis of the experiment process was carried out. Compared calculation results to experiment results synthetically, the damage mechanism and failure characteristics of reinforced concrete plate under explosion impact loading condition were got and it is also verified that the H-J-C model can approximately simulate the concrete properties well under explosion impact loading condition.

More and more high strength steel panels are used in the Auto assembly for the reason of reducing pollution emissions and fuel consumption. The springback predication with different drawing styles for A pillar reinforcement plate is studied in this paper. The drawing process is optimized with different height drawbead for getting a reasonable forming result without obvious crack areas. An open drawing is used to study the possibility of reducing the blank size, but the measuring results show that the springback value predicted with close ends drawing is very close to the real tryout results and more lower than open ends drawing. So the open end drawing method can not be used in the tryout from the perspective of reducing the springback value.

Equivalent elastic parameters of the honeycomb core considering the effect of extension or contraction deformation, shear deformation and flexural deformation are presented in this paper. Then the energy theory is applied to the calculation of the equivalent elastic constants Ee and νe. Finally the accuracy of the formulas have been verified by the compressing experiments with aluminum honeycomb core in the literature[9].

In the construction of high-rise buildings, the effect produced by the excavation of deep and large foundition pits on the surrounding structures cannot be ignored. This paper presents a case study from a construction project located in Nanjing, in which the dynamic excavation process of a founditon pits is numerically analyzed with finite element method on Plaxis. The impact of various excavation stage on subway tunnel nearby is achieved in terms of the results of data analyses and assessments.

Based on the concept of bionics design, this paper aims to research the basic theory of bionic design methods, design procedures and the development trend of mini hair dryer, intending to build the bionic design methods in production, pointing out the method of process in order to achieve the bionic goals, appreciating the biological characteristics, record, simplification, painting and biological characteristics of the product design. Hopeing to apply this method to promote other products design and trying to search a fast and effective way for products innovation.

In the deep rock mass surrounding, rock burst, large deformation, zonal fracturing and phenomena like these may occur in the tunnel excavation process. When zonal fracturing happens, it is essential to reconsider the types of support, the boundary of support and the approach of tunnel excavation. In this paper, the control theory about the surrounding rock stability under high pre-existing stresses was researched, and the efficient support form which was the combination of high strength anchor bar and anchor cable was ascertained to be adaptive to deep tunnel excavation. According to the deformation and zonal fracturing mechanism of the surrounding rock, a comprehensive support program that combined intensive short anchor bars and long anchor cables was established, and the numerical simulation was carried out to verify the feasibility of the support form.

A new method that is to use soilbag filled with sludge instead of using jackstone has been proposed to construct the sea wall recently. With this new method, expenses of building the sea wall can be cut down and environment pollution around the sea wall can be reduced. An analytical solution for soilbag with semi-pervious boundary is proposed in this study. The cross-section of the soilbag in this theory is considered as a rectangle. By setting coefficients for consolidation solution of two square areas and summing the two parts, final solution of the rectangular area is obtained. Further research is made to compare calculation results from this study and other three methods. After the comparison, it concludes that calculation results from this study are very close with that of finite-element method, and also, the soilbag method possesses a giant economic benefit and has a possibility to replace the jackstone method to construct a sea wall.

LED chips position is of crucial significance in chip testing, scribing, die spreading, and die bonding. It’s a great solution to indicate electrical characteristics of chips, examine whether the chip pins are up to the standard, and distinguish LED chip quality. Concerning this, an LED chip positioning method based on wavelet transform is proposed in this paper. Firstly, CCD, light and motion control module are adopted to construct and acquire the visual system of LED chip images. Then the images are processed with lowpass filtering and normalization to obtain Hi-Q chips image, and image features are extracted by further using multi-scale wavelet transform. Lastly, high accuracy positioning of LED chips is achieved by employing high-accuracy point pattern matching algorithm. Experimental results show that the LED chip image positioning error is less than 1μm and the position speed is faster than 5 particles per second, which offer new approaches for high-accuracy chip positioning system of detection machines, sorting machines, die bonders, etc.

With the increasingly outstanding of the traffic safety issue, the human factors in People-Vehicle-Road System are being emphasized gradually. Takes Jinhua suburb asphalt mountain road (two-lane, multiple steep slopes) for example, this study focuses on road engineering response analysis on driving reaction, design optimization of road engineering base on driving response. A driver over 3 driving years steered 5-seat car in 4 kilometers long experimental road, kept the vehicle speed (V) under 40km/h. Heartbeat rate of the driver was monitored by dynamic Holter through driving process. The analysis shows that there is a linear positive correlation between Heart beat growth rate (Ni) and V, a nearly positive correlation between lateral force coefficient (μ) and Ni, and nearly inversely proportional between plane curve radius (R) and slope (i). It should decrease R appropriately when road slope (i) much sharply in road alignment design. There is a polynomial relation between Ni, V and R. As R increases, both Ni and V reduce firstly, and then rise. When R ranges from 240 to 500 meter, stress gradually ease; while R exceeds 500 meter, driving reaction tension gradually rise. R

The paper points out that the figure symbol “ ” should be named as “double zero”, not infinity. “ ” has the similar meaning as “0”. They all express no numerical value. In this paper, the application based on the definition above in probability theory is discussed.

This paper uses biped walking robot as the research object, and designs robots original system, based on the requirements of Biped Walking Robot Competition of China. According to the biped walking robots characteristics of multi-joints, many degrees of freedom, multivariable, strong coupling and nonlinearity [, we can build system model using the Denavi - Hartenberg coordinate, describe the system model by the homogeneous coordinate transformation theory, and then plan on system gait based on ZMP stability . Finally, we can solve for the joint trajectory of the system by using computer-aided software.

Magnesium has been recently recognized as a biodegradable metal for bone substitute applications. In the present work, a novel magnesium based scaffold with a specific two-layer structure was prepared for powder metallurgical process. The outer layer of the scaffold shows an interconnected porous structure, so that the fresh fluid can be easily sent into the material, allowing the ingrowth of new bone tissue. The inner compact structure reinforced by the salt particles can increase the strength of the material. Structural characterizations and mechanical tests of the materials demonstrate that the structural and mechanical properties of the magnesium-based scaffold with an appropriate salt content prepared by the current method are quite comparable to those of cancellous bone. Therefore, the magnesium-based scaffold with such a two-layer structure has the potential to serve as degradable implants for bone substitute applications.

Microstructures, phase compositions and microhardness distribution of two kinds of natural biological materials called Burnt-end Ark and Veined rapa whelk shells were studied and discussed for comparisons. It was found that the both shells present a hierarchical structure comprising three layers in thickness, i.e., inner, middle and outer layers. The inner and middle layers of the two kinds of shells exhibit cross-lamellar structures with somewhat of differences in the morphology and dimension. The outer layer presents a porous blocky structure for Burnt-end Ark shell and a layered structure for Veined rapa whelk shell. The X-ray diffraction (XRD) analyses show that all the layers of Burnt-end Ark shell as well as the inner and middle layers of Veined rapa whelk consist of crystalline aragonite CaCO3, while the out layer of Veined rapa whelk consists of crystalline calcite CaCO3. The microhardness measurements on the cross sections perpendicular to the growth lines of the shells demonstrate that the hardness of the both shells decreases gradually from the inner layer to the outer layer, strongly depending upon their microstructures.

The need for sensor interoperability has increased tremendously in many large-scale fingerprint applications such as e-commerce, welfare-disbursement and e-education. In this paper, we present fingerprint scaling, an innovative fingerprint system module, which resizes the fingerprint images to solve the problem of sensor interoperability with minimum modification to existing system. In template-based scaling methods, we have developed an estimation method using Delaunay triangulation algorithm. The efficacy of the scaling technique has been assessed by embedding a scaling module into a traditional fingerprint recognition system. Our experiments have shown very positive results. Experimental results indicated that the accuracy and robustness of fingerprint system can be improved effectively by embedding such a scaling module into the traditional framework of fingerprint systems under multi-sensor situation.

This paper studied how to quickly draw the roll engineering drawing thorough ARX application program, introduced and analyzed the layer, linear, size tolerance Settings, and geometric tolerance Settings. On this basis, citing specific examples will be described, and listed the specific examples to explain. At last speaked on design idea and the development steps for roll rapid drawing system, completed the ARX applications of manufacturing circular tube roll. Those ARX application program loaded in the AutoCAD2002, automatically drawed mechanical drawing of roll by inputting characteristic value, liberated the drawing technicist, saved plenty of manpower and material resources.

As the technology of sensor network advances, wearable health monitoring becomes feasible. Here we present a context-aware monitoring system for cardiac health, which consists of three modules: signal acquisition for physiological signal as well as context information; processing, analysis and interpretation of signal modality as well as fusion of context to generate cardiac health indices; interface for human-machine interaction. Both captured original data and analysis results are stored in an SD card for further processing in the server. The system works continuously for 24 hours. The proposed cardiac health indices can be applied for health status monitoring and early prediction of cardiovascular disease.

A series of waterborne cationic perfluorinated polyacrylate (WCFPA) were prepared by the reaction of styrene (St), methacrylatoethyl trimethyl ammonium chloride (DMC), butyl acrylate (BA), octadecyl acrylate (ODA) and 2-(perfluorooctyl)ethyl acrylate (FEA) by soap-free emulsion copolymerization and then the films of the WCFPA were prepared. Their structure and water/oil repellency properties, such as surface property, water and chemical resistance of their membrane were characterized by fourier transform infared spectrometer (FT-IR), interfacial tension instrument (IT), contact angle (CA) and spot test. The results reveal that WCFPA was endowed with low surface energy of its film. It was also found that the fluorinated polyacrylate had outstanding water and chemical resistance. Increasing the FEA amount in the emulsion was as sociated with larger contact angle and better water and oil repellency.

The precipitation behaviors were investigated during isothermally aging at 700°C and 800°C after cold compressed by 30% in thickness in Fe-18Cr-12Mn-0.48N high-nitrogen austenitic stainless steel by using optical microscopy (OM), laser scanning confocal microscopy (LSCM) and transmission electron microscopy (TEM). The results show that precipitation morphology in cold-deformed sample is the same as non-cold-deformed sample, which also displays discontinuous cellular way. Cold deformation accelerates the precipitation of M2N phase. The precipitation occurs at not only grain boundaries but also twin grain boundaries in the experimental steel. In cold-deformed sample, besides the long-strip M2N precipitates, intermetallic phase-σ phase owning bct structure and lattice parameters of a=0.8800nm and c=0.4544nm were observed along grain boundaries and inside the grain.

The fuel ethanol industry has been in rapid development in recent years with the US as a leading force, which consumes large amount of corn. In order to assess the impact of corn-ethanol production on global corn price, a VAR model is used in this paper. By impulse responses analysis and variance decomposition analysis the direct impact of corn-ethanol production on global corn price and its relative importance compared with other external factors are proved. The results show that increasing amount of corn used for US ethanol production leads to rapid increases of global corn price when the corn production is steady. The proportion of corn used for ethanol production among total corn production in the US plays an important role in affecting global corn price among all external factors, and the significance of its impact will enhance in the long run. The fuel ethanol industry should turn to non-grain materials in the future to keep the global corn price steady and guarantee global food security, and it’s necessary for all fuel ethanol producers to take action.

As a new type of controllable rheological smart material, Magneto-rheological Fluids (MRF) are widely used in the field of vibration control. This article investigated their integrated dynamic characteristics in squeeze mode and shear mode. Two prototypes were designed and fabricated. The dynamic test for the two prototypes was performed on a simply supported beam vibrating device with the methods of drop-hammering and sweep-frequency measuring. The experimental results demonstrate that the damping ratio of the prototype in squeeze effect presents linearly and widely controllable from 0.0948 to 0.2268 with the increase of the coils’ excitation current, behaving as a variable MR damper. However, its natural frequency remains unchanged. It is also shown that the natural frequency of the prototype in shear effect increases significantly from 18Hz to 24 Hz, acting as a semi-active dynamic vibration (SDVA) absorber with broadband vibration absorption for the maximum attenuation of up to 74.3%. This study provides guidance for engineering applications of MRF.

Traditional Static Synchronous Compensator(STATCOM ) compensates most singly for reactive power or steady state voltage in high power field. On this point, the paper puts forward a harmonic frequency compensation technique, which can realize dynamic reactive power compensation as well as harmonic control of less than 20th power. Then, using average switching method, it gives the mathematical model on the device. Active and reactive current decoupling is realized. For the electrical model, the compensator developed uses 8-cascaded H bridge structure, together with the carrier phase-shifted SVM technology, can realize 17 level voltage waveform output, having high utilization and easy to realize digital. Finally, simulation and experimental results show that the harmonic frequency control technology developed for 6kV cascade compensator can be used on the actual electric network, with low switching frequency. The device can together compensate reactive power and control harmonic accurately and effectively.

The present work deals with a method for the modeling of a three-way servo-proportional valve actuated by a proportional solenoid. The model incorporates the primary nonlinear phenomenon exist in the solenoid, such as the hysteresis, nonlinear inductance and counter-electromotive force. Two ways are employed to simplify the model for the purpose of controller design. Firstly, the relations of current supply vs. flux linkage and flux linkage vs. electromagnetic force under different displacements of armature are captured by curve fitting and interpolation, with the advantage of keeping the nonlinear characteristics. Then the linearization method around the null-position of the spool is implemented, where the solenoid is modeled as a 1-order system, and the body of valve is treated as mass-spring 2-order system. Then the test-bed for the identification of main parameters and verification of the model is designed. The parameters are obtained from the experimental results where the armature and spool are locked at different positions. Finally, the model is verified as the dynamic responses of current supply and displacement of spool obtained from the simulation model agree well with the experimental results when the armature and spool are unlocked.

Experimental equipments are designed for the zero-crossing method of dynamic laser speckles to investigate the moving nature of nanoparticles in flowing nanofluids. After the experiments the velocity of nanoparticles in flowing nanofluids is determined according to its relationship with the zero-crossing rate of speckle intensity fluctuation. The results show that the zero-crossing rate is very sensitive to the velocity of nanoparticles when the velocity of nanofluids ranges from 17.6 mm/s to 60.2 mm/s. A TEM10 mode–like laser beam is designed and taken as an incident light to detect the moving direction of nanoparticles in flowing nanofluids. The moving direction of nanoparticles is parallel to the horizontal axis of the TEM10 mode-like laser beam when the zero-crossing rate reaches maximum. Experimental results show that the moving direction of nanoparticles can also be detected by using the zero-crossing method.

Experiments were performed to investigate the As(III) and As(Ⅴ) removal on manganese dioxide. 0.5 grams of manganese dioxide was reacted at room temperature for 3 hours with 50 mL As(III) or As(V) in synthesized groundwater. Throughout the reaction, concentration of arsenic decreased from 1.25 mg/L to 0.70 mg/L in As(Ⅴ) system, arsenic removal was about 44.27%. While in As(III) system, concentration of total arsenic decreased from 1.92 mg/L to 0.85 mg/L, arsenic removal was about 55.85%. When As(III) reacted with manganese dioxide, the concentration of As(Ⅴ) in solution reached the maximum value for the oxidation of As(III) after 45min, afterwards As(Ⅴ) decreased slowly for adsorption on manganese dioxide. In regard to total manganese concentration, it was 1.25 mg/L in As(III) system, was about 1.25 times of that from As(Ⅴ) system, this phenomenon was due to the redox of As(III) with manganese dioxide.

Along of the rapid socio-economic development, population growth and the development of urbanization, the contradictions of water’s supplying and demanding in city are growing. Author advanced the Liu-yang city should strengthen water system planning and Set up a beautiful environment with resource advantage. Analyze the Liu-yang city water system’s current situation and issue by the “Pollution Treatment, Increase Income and Decrease Expenditure” strategy. Explored the small town water system’s planning from the main city zone water system planning, water resources protection and water supply planning, landscape water system planning.

Microencapsulated phase change materials were prepared by the interfacial polymerization method with polyurethane resin as the shell and disodium hydrogen phosphate dodecahydrate as the core. The factors which affect the diameter distribution, surface morphology and thermal properties of microencapsules were investigated by the means of SEM, DSC and TG. The results show that the diameter distribution is uniform and the microencapsules have high compactness. The particle size is centralize with the stirring rate of 8000r/m and emulsifying time for 30 minutes. The DSC results show that the melting point of the phase change material does not have much change and phase change thermal storage is obvious

As an important pre-coding method in MIMO- OFDMA system, zero-forcing beamforming (ZFBF) can eliminate co-channel interference (CCI) between users, and generate a series of parallel spatial subchannel without interference. In this paper, we propose a novel ZFBF-based user scheduling algorithm for multi-user downlink MIMO-OFDMA systems. The algorithm can satisfy the rate requirement of each user, choose the right user set in each subcarrier and minimize the total transmit power. Simulation results show that the proposed algorithm does outperform the non-adaptive algorithm and SUS-algorithm.