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This research compared and analyzed the adaptation of four evapotranspiration equations: the FAO56 Penman-Monteith (PM), Priestley-Taylor, Hargreaves-Samani and Thornthwaite equations by using the day-to-day meteorological data of the 42 observation stations in the Pearl River basin. Numberical simulation of the four equations in different seasons and regions was made in order to find out the most suitable one for the evapotranspiration estimate in the Pearl River basin. Results show that the calculation results of the PM equation seem more stable in different seasons and regions, and is closer to the actual observation, due to the detailed consideration of the effects of aerodynamics and energy supply on evapotranspiration in its calculation procedure. The missing data of relative humidity, sunshine duration, wind speed and air pressure would have influence on the calculation accuracy of the PM equation. Temperature can be used to instead of the above variable in the PM equation, which is called the PMT equation. The applicability and the calculation accuracy is explored in this study. And the results show that the calculation results of the PMT equation is larger than those of the PM equation. By setting a correction coefficient in the PMT equation, the calculation accuracy can be obviously improved. Therefore, in the absence of other data, the PMT equation calculated only using temperature data can be use as an ideal equation for the evapotranspiration calculation and research in the Pearl River basin.

In this work, tungsten thin films were deposited on different substrates by magnetron sputtering and some of the films were then annealed at 1000°C for 1 hour in order to investigate the influence of different processing parameters on morphology and microstructure of films. Scanning electron microscope and x-ray diffraction were used to detect the morphology and microstructure of films. Under the same conditions, the thin films on different substrates showed different preferred grain orientations although the morphologies were similar. After thermal treatment, the morphology of films changed significantly and the total stress parallel to film surfaces dropped off sharply.

The paper adopts modified carbon fiber with Meldrum's acid and silane coupling agent (KH-550), then add the modified carbon fiber to the paper based friction materials. The paper aims to explore the changes of modified carbon fiber in its surface structure and properties by electron microscopy and infrared spectral analysis, and the effect of anionic microparticle forming retention aid system comprised of lithium soapstone-cationic polyacrylamide (CPAM) on mechanical properties and retention of paper based friction materials. Compared with the addition of unmodified carbon fiber to paper based friction materials, the addition of modified carbon fiber with Meldrum's acid, silane coupling agent, Meldrum's acid and silane coupling agent enhance the tensile strength of paper based friction materials. The tensile index of paper based friction materials was separately enhanced by 64.87 %, 91.38 % and 28.88 %. Compared with the paper based friction materials without the anionic microparticle forming retention aid system, the basis weight of paper based friction materials increased by 13.97 %.

By changing ther factors of synthesis process of PAE, discussed the effects of synthetic conditions on the PAE curing, and through electron microscope analysis methods, the curing mechanism of PAE is preliminary discussed.When the ratio of DTEA/AA was 1:1.05,the dry and wet strength of paper before and after curing achieved the best value.when the dosage of p-toluene sulfonic acid is 1.5%, the PAE can achieve best effect.the best ratio of PPC and epichlorohydrin is 1:0.7.

This paper mainly discuss the effect of beating on OCC pulp fiber morphology and paper physical Strength. After the treatment with PFI, the beating degree were ranged from 25 ° SR rises from 56 °SR, the fiber morphologies were greatly changed, and appeared splitting and brooming. Physical results showed that beating can improve strength properties of OCC pulp in the proper degree, 46°SR was the best result in this study.

Ni-doped copper nitride films have been prepared by co-sputtering of Ni and Cu targets. The addition of Ni to Cu3N films reduced the intensity of the (111) diffraction peak, and lead a little angular shifts of the peaks. The films showed a large difference in reflectance in the infrared and visible before and after thermal decomposition, which is applicable to optical recording media. The films change from a semiconductor to a conductor with the increased ratio of Ni in Cu3N films.

Hydraulic press occur elastic deformations in the working status. The deformation will affect the precision of the products. This paper expounds the method of using Laser tracker test rigidity of THP11-10000A isothermal forging hydraulic press. And we test the deformation of the lower bean, fit the date and compare with fitting of the finite element simulation results. The validity and the accuracy of the simulation results are verified.

An optical scheme using two correlationless beams to suppress the speckle of the pico-projection system is proposed. By using two broadband beam splitters (BBS) and two high reflection mirrors, the originally incident laser beam is split into two beams. The mutual correlation coefficient between two split beams is very close to zero. We use the haze reflection based on the random scattering model to simulate light reflected from the rough surface. In simulations, light is respectively reflected from the same size flat and rough surfaces and both recorded images are compared with each other. The image from flat surface is very clear on the detector plane. On the contrary, the image from rough surface is very fuzzy and the edge is hard to figure out. The simulations show that the speckle contrast ratio (CR) is reduced from 1.0 to 0.707. We find out a solution of the speckleCRless than 0.71 when the distance between two BBSs is 2.4 mm and the thickness of each BBS is 0.4 mm. Finally, we carry out an experiment and verify the simulating results. By our analysis from the experimental data, the speckleCRcan be reduced about 25% which is close to the theoretical value of 29.3%.

A program based on the SOR method have been setup for calculating the electrostatic potential inside the electron optical system (EOS). This method can deal with large domain calculation more efficiently than by using the finite difference or finite element methods. Since the MEBDW system is composed of an array of EOSs, periodic boundary conditions in thexandydirections are applied. A case of EOS is demonstrated in this paper.

The variable tension control system of strip winding is a nonlinear, strong coupling and time-varying system. Traditional fuzzy controller with fixed control rules cannot obtain the desired control performance of the strip winding system. So the fuzzy control algorithm with adjustable factorαis proposed, and the introduction of adjustable factors can change the fuzzy control rules. The tension fuzzy controller with adjustable factorαis designed, and simulation model of the system is established using Matlab software. The result of simulation shows that tension fluctuation of the tension fuzzy control system with adjustable factor get small, comparing the tension fuzzy control system with adjustable factors with the ordinary tension fuzzy control system. The tension fuzzy control system with adjustable factors has fast system response and strong anti-interference ability.

This paper used the finite element software ANSYS to simulate the thermal assembly process of the roller sleeve of the HFCG160 roller press, and study the change of the temperature field. And then, comparing the simulation temperature with the test temperature, the results show that the simulation temperature is basically consistent with the test temperature, while there are slight biases on the individual points within a certain period of time. The main reason for biases between the simulation temperature and the test temperature is that the convective heat transfer coefficient is average during the simulation, which ignoring the convective heat transfer coefficient decreases with the decreasing of temperature.

In this experiment, we use corn starch as the main raw material and use Mid-Temperature a-amylase to modifie it. The influnce of temperature and time to viscosity of the enzymatic starch were discussed. In this way, we can get the optimal conditions about enzymatic modification. According to testing properties of the paper ,we know about its surface sizing effect. At last,we explored the influnce of AKD to surface sizing. The results showed that the optimal conditions are as follows: the optimal enzyme reaction temperature of 65 °C and the ptimal enzyme reaction time of 20min under the condition that the substrate concentration of 20%, the dosage of enzyme of 0.02%, the dosage of calcium chloride of 0.04%, pH 6, gelatinization temperature of 95 °C, and gelatinization concentration of 10%.Under this condition, the viscosity of starch paste is 11mPas. Compared with original paper, sizing increased by 16.20%, burst index increased by 10.50%, tensile index increased by 12.60%. The AKD can significantly improve the degree of sizing, compared with the original paper, the degree of sizing increased by 26.5%.

Based on the domestic OCC pulp as raw material, it was found that the optimum conditions for laccase treatment were: the concentration of laccase 16U/g dry pulp, the pulp consistency 5%, temperature 50 °C, pH=5.0 and reaction time 90min. OCC treated with laccase alone can improve paper strength properties. The dry tensile index and wet tensile index of the control sample were 21.80 Nm/g and 0.22 Nm/g, respectively. The dry tensile index and wet tensile index after OCC treated with laccase alone were 23.36 Nm/g and 0.28 Nm /g. Comparing to the control pulp, the dry tensile index and wet tensile index of OCC treated with laccase were increased by 6.88% and 27.3%, respectively. At the same time, the laccase system can obviously improve the strength of the pulp properties with adding the mediator, especially using histidine, the dry and wet strength of paper was largely improved.

In this study, we prepared unbleached chemi-mechanical pulp from waste poplar wood using alkaline processing under normal atmospheric pressure. The influnce of alkaline dosage and time to fiber morphology and properties of the paper were discussed. The parameters of fiber including the length ,width and curl index were measured by FQA. The optimal dosage of NaOH and the optimal time of soaking period in the preparation of pulp using waste poplar wood were studied. The results showed that the optimal dosage of NaOH was 6% and the time of soaking period was one day. The performance of the handsheet made from the poplar wood under the pulping conditions are as follows: tensile strength index of 27 N·m/g, tear index of 0.51 mN·m2/g, burst index of 1.7 KPa·m2/g, folding strength of 16 times, ring crush strength index of 5.7 N.m/g, whiteness of 55.5 ISO, white opacity of 97%, paper absorption liquid rate of 0.32 mm/s.

With the development of world's paper industry, strength agent has become increasingly wide spread and more important.This paper describes a method for modified APMP with Chitosan, we make studies on using chitson to improve the properties of paper, and compare the effect of them based on experimential results. As a result of study,it can be concluded: The pH value and the dosage of chitosan have a great influence on the physical strength of paper.When the pH was 6 and the dosage of chitosan was 1%,the tensile index of paper could reach 30% above.

By the preceding experiments, we concluded that the optimum conditions for laccase treatment were: the concentration of laccase 16U/g dry pulp, the pulp consistency 5%, temperature 50 °C, pH=5.0 and reaction time 90min. We studied the change of water retention value and carboxyl content changes under the best conditions. As well as we studied the effect of pulp strength properties by biological treatment combined with mechanical treatment. Moreover, environmental scanning microscope images showed that more collapse and more fibrillation were observed on the beating combined with laccasehistidine-treated fiber surface than the control samples, which led to form better bonding between fibers in handsheets resulting in the increase of the paper strength of beating combined with laccasehistidine-treated OCC pulp.

initiator is one of the most important conditions of synthesizing efficient strength agent CPAM. To begin with initiating mechanism, three redox systems of acrylamide aqueous polymerization (NH4)2S2O8/ Na2 SO3, K2S2O8/NaHSO3 and K2S2O8/Na2 S2O4 have been studied. The effects of different kinds of initiator, initiator concentration, and monomer concentration as well as polymerization temperature on relative molecular weight and strength effects of CPAM have been investigated. K2S2O8/Na2 SO3 is the most useful system in synthesizing efficient strength agents.

The paper has learned on the preparation of nanometer carbon black and polypropylene nanocarbon black-polypropylene composite material by using the small extrusion blending mixer which has been designed by our team. The results show that: Resistance of nanometer carbon black - polypropylene composites decreases with increasing carbon black content and extrusion mixing times. Through single factor experiment and orthogonal experiment to determine the optimum process conditions are at 260°C, nanocarbon black content 60%, extrusion mixing times 5. Under these conditions the resistance of nanometer carbon black-get polypropylene composites is 12.73 ohms.

With the development of technology, the agricultural industry has become far more efficient and mechanization. In this paper, image processing method was adopted to detect the changes in seeds temperature, aiming at discovering the laws in seed germination. Oak seeds were selected as samples. The method can be divided into two steps----image segmentation, data extraction and analysis. 32400 images for 90 seeds were captured, and the changing curve of seeds temperature was described based on the images we collected. The result showed that the method was available to capture the changes of seeds temperature during its germination. Even, further research aiming at distinguishing seeds vigor by temperature information, is of great value.

The research of conductive polymer material has received the widespread attention and development. This article has introduced the classification and preparation methods of conductive polymer materials, conductive mechanism, application and research progress in various fields.

In this paper, the theoretical equation of flow injection-cathodic potentiometric stripping analysis for Cl-ion determination was derived from theoretical analysis, and the experimental equation was summarized using multiple linear regression method. The result shows that the theoretical equation of flow injection-cathodic potentiometric stripping analysis for Cl-ion is: (dt/dE)max=K Apr-1/2D2/3-1/6Vf1/2teCx-/is;that the experimental equation of multiple linear regression method is: (dt/dE)max Cl-1.86×1010Vf0.568teCCl-/is. The two results are similar on Vf-average flow rate, te-concentrate time, CCl--Cl-ion concentration and isconstant current.

A kind of refractory fiber cardboard functioning as building insulation materials was developed. To improve the cardboard abilities to bear high temperature, sepiolite and alumino-silicate fibers were chosen as the raw materials for making refractory fiber carboard. In addition, inorganic adhesives and PVA fiber were used as bonding agents to enhance the physical strength of cardboard. The effect of bonding agents amount on tensile strength of the cardboard were investigated. When choosing inorganic adhesives and PVA fibers as the adhesives, the optimum condition is that amount of aluminum sol and PVA fibers is 30%and 3%-4% by weight, respectively; The best technical conditions for making the refractory fiber cardboard were determined. When the mass ratio of alumino-silicate fibers, sepiolite fiber, PVA fibers is 90: 6: 4, the physical strength of refractory fiber cardboard can be up to 1.556N·m/g. When the bulk density of the cardboard is 305.8kg/m3, the thermal conductivity of insulation cardboard at 200°C is very low, which is only 0.065W/m·K.

In this thesis, the process of electromagnetic drying cylinder was analyzed creating by the dryer finite element model using ANSYS. The conduction thermal analysis, the applied load and solved showed the results of three major components. Which create a finite element model of the process, mainly the preprocessor using ANSYS software to create or import geometric models from other software applications, and then add the material properties. The last of the geometric model meshing and solving process need to enter solvers according to the actual situation. The setting is applied to the thermal load and conditions. Then it is proceed to the finite element solution operator. It final usually the Post 1, or Post2 view results, and based on our experience to judge correctly

Aimed at the welding initial defect fatigue extension of 300t converter loop in a factory, the whole assembly finite-element (FE) model of converter loop with the welding initial defect is established. The converter loop FE model with different depth initial defect is computed by using 3D nonlinear finite element method at different tilting angles. And the stress intensity factor is extracted and analyzed under different working circumstances. The analysis results show that when the initial defect depth is greater than 11.715mm, the defect will result in fatigue crack extension at the complex alternating stress. To solve the cracking leakage problem of converter loop, the original welding manholes is replaced by the movable manhole. In the past over one year, the fatigue cracking and leaking phenomena did not occur in the converter loop, so the effect is obvious.

A photonic crystal waveguide coupled structure can be constructed by putting three photonic crystal waveguides in parallel and adjacent form. Study the coupling of the approximate solution interference acts and the self-image phenomenon of this multi-mode waveguide system based on the guided mode propagation analysis method, a three-channels multimode interference wavelength division multiplexing is designed. The presented device not only has a high transmission rate, but also has the advantages of multiple wavelength selection and may have potential and practical applications in the field of photonic integrated circuits in future.

The aims of prehydrolysis are mainly removing pentose and decreasing viscosity in the preparation process of dissolving pulp. In this paper, the effect of prehydrolysis in the preparation process of poplar and bamboo dissolving pulp were investigated under different prehydrolysis conditions. The optimum prehydrolysis process conditions of poplar were obtained as followings: the liquid ratio of 1:6, the highest temperature of 160±2°C, heating time of 90min, holding time of 120min, H2SO4 of 1.0%, the P-factor was 1537. Under this condition, the results showed that the content of pentosan decreased from 24.10% to 7.85%. The optimum prehydrolysis process conditions of bamboo were obtained as followings: the liquid ratio of 1:8, the highest temperature of 160±2°C, heating time of 90min, holding time of 120min, H2SO4 of 1.0%, the P-factor was 1549.And the content of pentosan was also decreased from 19.64% to 6.76% by the prehydrolysis process.

In this study, the high density 900kg/m3 biodegradable cellulose fiber composites have been successfully manufacture from treated cellulose fiber by wet-hot pressure technology. The cellulose fiber was treated with cationic guar gum(CGG) by the process of adsorption. It was found that the composite made from treated cellulose fibers have better mechanical properties such as the tensile properties and stiffness. Chemical groups of samples were studied through the use of FTIR spectroscopy.

Sepiolite has good adsorptivity due to their high surface area and structural channels. During the process of making aluminium silicate fiber paper, inorganic binders retaintion was little because of the smooth surface of aluminium silicate fibers. In this study, sepiolite was used to improve tensile strength of the sheet by increasing inorganic binders retaintion rate through its high adsorptivity. The effect of sepiolite on the tensile strength of alimunium silicate fiber paper was investigated. The results showed that the best mass ratio of aluminium silicate fibers to spiolite was 7:3. Under this condition, the tensile strength of the sheet was 4.79 N•m/g, which increased by 24.2% from the one without sepiolite.

In this paper, we proposed the method to synthesize the modified polyamide polyamine enhancer, which takes PAE, styrene and acrylic as raw materials. Factors that would affect the preparation of the modified polyamide polyamine enhancer, such as monomer amount, reaction time, initiator amount and emulsion concentration, were discussed in detail. Experimental results showed that the modified polyamide polyamine enhancer achieved optimum effect the strength of tube roll base paper under the conditions: the amount of acrylic is 6%, the ratio of styrene and PAE is 2:1, holding time 4h, and the amount of initiator 0.7%. The modified polyamide polyamine enhancer applied to tube roll base paper. The optimum amount of modified polyamide enhancer was 1%. The ring crush strength of paper prepared in this condition can be increased by 44% and the stiffness can be increased by 46%.

PAE as the wet strength agent has a long history; it not only has the wet strength performance and the retention and drainage characteristics. This paper focuses on the technological conditions of preparation of PAE wet-strength agent and the application conditions. The results showed that the well PPC was obtained under the following conditions: the mole ratio of adipic acid and diethylenetriamine were 1:1.05, the amount of catalyst (mole ratio of the total raw materials) was 1%, the temperature of heat preservation was 165°C and the reaction time was 4h. The optimum condition of preparing PAE was obtained as followings: the ratio of EPI to PPC of 1.2:1, the epoxidation temperature of 60°C and reaction time of 2h. While applied in softwood pulp, when the dosage of PAE was 1%, the wet strength agent provided the satisfactory effect.

The nondestructive estimation of key parameters during plant-field chicken manure composting is of great importance for quality evaluation. In the process of developing regression models using near-infrared spectroscopy (NIRS), methods used for wavelength selection significantly influence on the efficiency of the calibration. This study explored the method of genetic algorithms (GAs) for selecting highly related wavelengths to improve NIRS models for moisture (Miost), pH and electronic conductivity (EC), total carbon (TC), total nitrogen (TN) and C/N ratio determination in chicken manure during composting. Based on the values of coefficient of determination in the validation set (R2) and root mean square error of prediction (RMSEP), the prediction results were evaluated as excellent for Miost, TC and TN, good for pH and EC, and approximate for C/N ratio. But GAs had better performance than using full spectrum for near-infrared spectroscopy model construction in the process of evaluating key parameters during plant-field chicken manure composting.

In order to realize the curve welding seam tracking of welding tractor, the welding tractor driven by two rear wheels is researched in this paper. The control system that a DSP controls two DC brushless motors is designed. It contains the whole system design, hardware circuit and software design. It is designed as a double closed loop system. Experimental results verified the feasibility of the whole system.

Kinematics model of welding robot is built in the paper. An improved fuzzy controller (Fuzzy-P) for welding robot mobile platform is designed based on analyzing seam tracking control system. The domain of fuzzy control should not be set too big in order to make system smooth, but the system must respond rapidly. P control can respond rapidly. When weld seam deviation is big,it adopts P control while seam deviation is small, it adopts Fuzzy-P control. The simulation result shows that the improved controller is effective for 45°broken line; the welding torch is able to track the welding seam well.

Present Measurement and test system for aeroengine rig testing is primarily based on DSP and PC104 industrial computer, which have the disadvantages of large volume, high power consumption, single function and less-generic. So it is a valuable job to promote the performance of the system employing the latest methods of collaborative design and embedded hardware and software technology. For designing of the new type improved aeroengine test system, a hardware and software co-design strategy is employed. After a thorough trade-off analysis and comparison among different hardware and software systems, an embedded aeroengine test system based on ARM and FPGA is designed, by using S3C2440A CPU with ARM920T core and FPGA from Xilinx as fundamental hardware data acquisition and process platform, using Linux as real time operating system. The data transmission between ARM and FPGA take the path of dual-port RAM, during which the read-write operation is coordinated by means of interruption. The system uses U-Boot to initialize hardware and load operating system. FPGA is used as foreside of data acquisition system, which sampling parameter setting is loaded by reading configuration file during start-up and read into inner register by SPI bus. Data is exported from flash-chip of test system by means of U-disk or network, and analyzed in PC equipped with specialized software. Strong post-proceeding capacity for multi parameters of aeroengine rig testing can be realized, especially for dynamic signal analysis in time domain, frequency domain. Because of the use of the new platform, a big promotion has been achieved. I) the capacity of data processing increases by 15%. II) The new system allows numbers of the sampling channels to double. III) Abundant functions of software can realize more professional, intelligent and generic tests. IV) Sampling frequencies increases by 20%, meeting the demand of monitoring dynamic random signals such as noise and vibration, on fluctuating pressure with wide frequency band. The embedded aeroengine test system based on ARM and FPGA is successful and the prototype is manufactured and tested. It is found that the performance of the new system is promoted significantly, which shows the effectiveness and reliability of the method employed.

We explored a new type alloy EAM potential (CLI-EAM) that the value of atomic electron density and pair potential between distinct atoms are obtained by Chen’s lattice inversion based on first-principles calculations. The alloy CLI-EAM potential acquired from NiAl alloy can also apply in Ni3Al successfully and the results of basic properties agreed with the experiments. The results of formation energy of point defects of NiAl and Ni3Al alloy indicate that the structural defects are anti-site defects of Al when enrichments of Al atoms.

Unsteady flow phenomenon occurs in a multi-stage axial compressor. The unsteady flow not only has significant influence on the performance of compressor and the stability of flow, but also can be an excitation source inducing Nonsynchronous vibration (NSV) of rotor blade. NSV is an aeroelastic phenomenon where the rotor blades vibrate at nonintegral multiples of the shaft rotational frequencies in operating regimes where classical flutter is not known to occur. Recently, more and more scholars pay attention to Rotating instabilities (RIs) as one of the unsteady flow phenomenon. RIs have been observed in axial flow fans and centrifugal compressors as well as in low-speed and high-speed axial compressors. They are responsible for the excitation of high amplitude rotor blade vibrations and noise generation. This research aims at revealing the relationships among the unsteady flow behaviors, characteristics of inner sound field and propagation, the vibration of rotor blade in multi-stage axial compressor. The noise in compressor and the vibration of rotor blade have been measured on a high pressure compressor rig testing. The transducer system is connected to the interior casing wall through the acoustic waveguide pipes. The noise is measured by 1/4 inch condenser microphones in different operating of the compressor. The time-domain wave of noise acquired at different work status of the compressor is transformed into frequency spectrum by Fast Fourier Transform (FFT) to investigate characteristics of sound field in multi-stage axial compressor. And the emphasis is focused on the frequency characteristics of the noise corresponding to blade nonsynchronous vibration. It is found that the vibration amplitude of the rotor blade suddenly increases in a pre-arranged structure adjustment and specific rotating speed, and noise signal with special frequency structures appears simultaneously. High amplitude levels of blade vibration have occurred on the first rotor of a multi-stage high pressure compressor. The frequencies are not in resonance with harmonics of the rotor speed. The frequency analysis show that the noise has a special frequency structures with combination of the appeared characteristic frequency and the blade pass frequency of rotor blade (BPF). Because the similarities between the frequency combination and the specific frequency structure of the fluctuating pressure when the rotating instability (RI) appears in the axial compressor have been identified, the acting mechanism of rotating instability may exist in this compressor, i.e. the vibrational excitation to the rotor blade may be aerodynamically caused and associated with a rotating flow instability in the compressor.

Nonsynchronous vibrations (NSVs) with high amplitude levels in the first rotor blades of a multi-stage axial compressor have been observed. The excitation is aerodynamically caused and associated with a unsteady flow field, including sound field. In order to investigate the characteristics of sound field in the axial compressor, the noise inner compressor casing are measured simultaneously with the vibration of the rotor blades on a high pressure compressor component rig testing. The results show that noise with specific frequency structures appear in the axial compressor under a pre-arranged structure adjustment and the specific operating conditions, and the noise spectrum characteristics are analyzed detailedly. Some influence factors such as rotating speed and corrected mass flow rate on noise characteristics are discussed emphatically. The results presented in this paper can be a reference for further understand of the characteristics of unsteady flow field and the effects of the high intensity sound waves on the rotor blades.

We explored a new type EAM potential (CLI-EAM) that the value of atomic electron density and pair potential functions are obtained by Chen’s lattice inversion based on first-principles calculations. This EAM potential is applied to Cu, Ag, Cu and Pt metals successfully and the results of basic properties agreed with the experiments. For the same metal, the cohesive energy of fcc structures are the lower than bcc structures.

In this thesis, a model of water injector is established, which can prevent water from splashing when high-velocity flow pours into a container. With the periodic boundary, the 1/18 calculation domain model is built. Then two-phase flow numerical simulation research is done on the device with the steady VOF model. The influencing factors of water injector's performance and the variation laws under different working conditions are obtained. The reliability of the results is improved by comparing the results from different calculation methods with that from steady-state VOF method. And through the experimental researches on the splash-proof water injector, the accuracy of the numerical simulation results is validated.

Exhaust noise is the major noise source of the internal combustion engines, and the exhaust silencer is the device to reduce the exhaust noise. Exhaust gas of the internal combustion engine is high-temperature, therefore in the study of internal combustion engine exhaust silencer, the surface temperature’s influence on the surrounding adjacent facilities should be controlled to a certain range and the status of the temperature field depends on the material and structure of the adiabatic envelope. The model of exhaust silencers discussed in this article is fluid-solid interaction model and this paper uses the CFD software for numerical simulation of the model. Using appropriate boundary conditions, calculation models and silencer model with heat transfer surface, this paper uses N-S equation and standard turbulent model to simulate the flow field and wall temperature field inside the silencer, and does post-processing analysis of the results.

This paper presents a thorough study of the wave-plate gas-liquid separators. The resistance curve has been obtained by the method of combining numerical simulation and experimental research. The separation efficiency curve under rated conditions for the droplet with different particle diameters has been obtained by using stochastic trajectory model. This can provide a new method for the research of wave-plate gas-liquid separator. The results obtained here may provide some new theoretical guidance for the development and optimal design of wave-plate gas-liquid separator.

Proprioception provides feedback that is vitally important for motor control. A deficiency in joint proprioception is thought to be associated with various upper limb rheumatological disorders. Currently, there is a lack of a portable device that could be used for measuring functional proprioception at the fingertips in the field. Therefore, a novel portable device for measuring pinch movement discrimination between index finger and thumb of either hand was constructed. This device is manually operated and requires the subject to make an absolute judgment of a joint position, choosing which one of five pre-experienced positions is being presented to them, with trials given in a random order. The 5 physical differences used were between 1.22 and 2.42cms. Reliability analysis was performed over a 7-day interval, with 8 healthy young adult volunteers. The discrimination scores, measured as the Area Under the Curve (AUC), for the group showed a mean (SD) of 0.794 (0.544) and 0.794 (0.549) on days 1 and 8, respectively. The day 1 and 8 reliability assessed with the interclass correlation coefficient ICC(3,1) was 0.85. Nondominant hands showed better pinch discrimination on the two days, with AUC values of 0.800 and 0.810 compared with 0.788 and 0.778, but these differences were not statistically significant (p>0.05). No difference in pinch movement discrimination was found between sexes. The ease of use and portability of the novel device for measuring functional proprioception at the fingertips described in this note make it ideal for measuring hand functional proprioception as part of clinical and epidemiological studies. The mid-range AUC discrimination scores found with healthy young adults mean that factors thought to diminish (eg. hand injury) or improve (eg. having expert finger skills) discrimination could be detected with the device.

The numerical simulation of the resistance characteristics of the inertial stage had been researched with different turbulence models, and the resistance characteristic computation curves of the inertial stage with different turbulence models have been obtained. Then curves contrasted with the actual value from experiments. The results show that the error of the Standard model is a little larger, but results of the RNG and Reynolds Stress are comparatively accurate. It has provided the reference frame of the turbulence model selection when the numerical simulation of the inertial stage is conducted.

The mesh of the multilayer gauze stage was simplified from the crossing arrangement to the unilateral arrangement, and the simplification from three-dimensional to the two-dimensional came true. The calculation capacity was effectively controlled by means of the periodic boundary. The numerical simulation of the multilayer gauze stage with different layers has been done. After the several calculation with different operating conditions, the resistance characteristic curves of the corresponding models was gave out. The relationship between the layers of the multilayer gauze stage and the resistance characteristic has been worked out. The experiments on resistance specialty of the multilayer gauze stage have been done on the special wind-tunnel. The experiment result was compared with the numerical simulation result, in order to provide the effective information for the further research.

Using such methods as questionnaire survey and experimental study, a study has been made on the effects of yoga on female college students’ body shape, the quality of physical function, mental health and so on. Methods: The study sampled 25 2009 female students in Handan College who have selected the yoga course. These students will do yoga practice for 6 months. The body shape, body function and mental health will be tested before and after the exercise. The results show that: such four indicators as body weight, waist circumference, thigh circumference and upper arm circumference; such 6 indicators as vital capacity, heart rate, VO2, sit-ups, step test, and Sit and Reach and such indicators as mental health self-assessment questionnaire (SCL--90), self-rating anxiety scale (SAS), and self-rating depression scale (SDS) have been improved significantly compared to those before practice. Conclusion: Through yoga practice, female college students can improve their physical health, balance physical and mental condition, and relieve stress, enhancing the quality of physical function and mental health.

A computational modeling and simulation method for multi-posture gymnastics jump based on sport biomechanics was improved. Taking tuck jump, pike jump and arched jump as examples, the entire jump phase was seperated into four parts: taking off from bending the knees, airborne, posturing and landing. Then the formulas were developed for modelling. Finally, computational simulation experiment was done with the formulas. The simulation outcomes showed that this method is effective in multi-posture gymnastics jumps analysis.