Study on Softening Constitutive Model of Malan Loess     

LUAN Chang qing  TANG Yi qun  LIN Bin 《保鲜与加工》2008,(2):53-56

In this paper, based on the uniaxial compression tests, consolidated undrained shear tests,consolidation drainage shear tests of Malan loess with different water contents, and based on understanding deeply of peculiar physico mechanical property of Malan  相似文献   

Analysis on function of several types polysilicate aluminum ferric      

ZHAO Hui ming  LUO Gu yuan  JI Tie jun 《保鲜与加工》2008,(6):694-697

Polysilicate metal salt exhibits excellent flocculation ability. Polysilicate aluminum ferric(PSAF) was prepared through copolymerization by sulphates and chlorides of aluminum or iron with polysilicate acid. The optimal hydrolysis parameter of different PSAFs was determined. Differences in turbidity and flocculation function of four types of PSAFs were evaluated. Furthermore, differences in coagulation and phosphorus removal were analyzed and discussed.  相似文献   

Stress wave effect in numerical simulation on rock breaking under high pressure water jet   总被引：1，自引：0，他引：1  

SI Hu  WANG Dan dan  LI Xiao hong 《保鲜与加工》2008,(8):942-945

The evolvement of rock damage struck by a high pressure water jet is characterized by nonlinear properties, thus making it a complicated dynamic problem. Based on a nonlinear finite element and elastic plasticity theory, a computational model was established. The dynamic load striking the rock by a high pressure water jet was simulated by the dynamic contact method. Furthermore, the propagation of a stress wave in the same rock was simulated at different impact velocities. The results show that the propagation velocity of a stress wave is proportional to the impact velocity of the high pressure water jet. The effects of a stress wave in sandstone and coal impacted by high pressure water jets of the same velocity were simulated.The effect of a stress wave in coal was stronger than in sandstone, while the region of propagation of stress wave in coal was smaller.  相似文献   

A control strategy for braking energy distribution and regenerative braking in a 4WD hybrid electric vehicle     

QIN Da tong  LI Jiang  YANG Yang 《保鲜与加工》2008,(9):971-976

Based on the braking theory of conventional vehicles and high efficient energy recovery and security braking, a control strategy for braking energy distribution and regenerative braking of a 4WD hybrid electric vehicle was proposed. Considering limiting factors, such as motor and battery efficiency, a simulation model of a regenerative braking system was built and a simulation of typical braking conditions was conducted. The simulation result shows that the highest energy recycle ratio can reach 87.5%, 47.8％, and 28.6％ when z is 0.1, 0.3, and 0.5, respectively, at 30 km/h. The control strategy for braking energy distribution and regenerative braking can satisfy demand for vehicle braking and obtain high regenerative energy.  相似文献   

X-ray diagnosis spectroscopy of laser produced plasma     

WANG Hong jian  XIAO Sha li  SHI Jun  TANG Chang huan  LIU Shen ye  QIAN Jia yu 《保鲜与加工》2008,(8):864-868

A new crystal spectrometer with high spatial and spectral resolution was designed to measure very low emissive X ray spectra of laser produced plasma in the 0.5 nm to 0.8 nm range. Twin channels collocated perpendicularly with two different crystal materials and forms were utilized for simultaneous measurement of spectral and spatial resolution. The imaging plate was employed to obtain high spatial resolution with effective area of 30 mm×80 mm. The basic parameters of crystals were analyzed and the design parameters of the spectrometer are presented herein. The first experiment was carried out at the 20 J energy laser facility of Research Center of Laser Fusion, CAEP. X ray spectra were obtained from Al laser produced plasmas with a spectral resolution of 1 000 to 1 500 for the spherically bent mica crystal spectrometer and spatial resolutions of 1.73 mm to 6.88 mm for the flat PET crystal in the same condition. It is suggested that the device be used in high density plasma diagnostics of a single laser shot.  相似文献   

Influence of information processing ability on human information system interaction efficiency     

YI Shu ping  LIANG Jing  YANG Wen cai  WANG Hai xia 《保鲜与加工》2008,(8):897-901

The essentiality of human information system interaction efficiency was analyzed under the computerization environment of enterprises. Information processing ability was measured from three dimensions: working memory, cognitive skill, and computer self efficacy. The experimental method was used to study the influence of information processing ability on human information system interaction efficiency. Multiple regression results show that cognitive skill is the main factor influencing interaction efficiency for skill based tasks, working memory is the main factor for rule based tasks, and working memory has no significant influence on interaction efficiency for knowledge based tasks. Working memory and computer self efficacy are the main factors influencing interaction efficiency for total tasks.  相似文献   

Heat transfer performance of heat pipe rotating about parallel axes     

HE Chuan  ZHAO Rong hang  ZHENG Jun 《保鲜与加工》2008,(6):632-636

We conducted an experimental study of heat pipe rotating about parallel axes. The entire pin fin of non contact thermal resistance was used in the cooling section of the heat pipes. The experimental liquid filled volume range from 10% to 25%, and heat flux density range was 7×103W/m2 to 5.3×104 W/m2. A cooling current of air was formed by the heat pipe rotation. The Reynolds number range was 2.3×103 to 1.2×104. The experimental results indicate that the heat transfer performance of the heat pipe was the best when liquid filled volume reached 20%. The heat transfer capability strengthened gradually along with the increasing rotational speed. The change of the heat power had little impact on the heat transfer performance of the heat pipe. It was found that the absorption liquid core was of little use to the heat transfer performance of the heat pipe. Under the same conditions, the heat transfer performance of the parallel rotating heat pipe was 1.5 times that of co axial rotating heat pipe.  相似文献   

Logistics distribution optimization technology for chainassembly manufacturing enterprises     

LEI Qi  LIU Fei  WANG Qi feng 《保鲜与加工》2008,(9):997-1001

According to the demand on just in time(JIT)distribution of chain assembly manufacturing enterprise, cost optimization of backup storage and distribution betimes were analyzed. A backup storage optimization model was formulated and quantitative analysis of the JIT backup storage optimization technology for the process of logistics distribution was carried out. The optimized distribution technique to realize JIT distribution was studied, and the distribution model of logistics center and the distribution algorithm flow were established. Finally, the proposed models were applied in the planning and construction of a logistics center of an electric appliance set chain enterprise with satisfactory results.  相似文献   

Deforming mechanisms in a non mandrel drawing process of an aluminum tube from circular to rectangular cross section     

QUAN Guo zheng  ZHOU Jie  AI Bai sheng  TONG Ying 《保鲜与加工》2008,(6):593-597

An elasto plastic finite element method (FEM) was used to study the deforming mechanisms of an aluminum tube drawn without a mandrel from a circular to a rectangular cross section. The simplified dynamics model and FE model of the non mandrel drawing process were established based on the FEM software deform 3D and simulations subsequently performed. Based on the simulation results, the influence of different semi die angles on the drawing load was summarized, and the proper values were found. As for the blank instability during the drawing process, the tangential stress distribution rule along the rectangle sides was acquired. The drawing die sizing section then was modified with a camber angle of 178° to eliminate instability. The touch boundary and touch stress distribution during drawing process also were analyzed. The aluminum tube produced by the optimized drawing die possesses eligible dimensions and smooth inner surfaces.  相似文献   

Handling performace evaluation of a vehicle stability control system based on a driver model     

HE Yan song  LI Xing quan  XU Zhong ming 《保鲜与加工》2008,(10):1098-1102

By combining a driver model, a vehicle system dynamics model, and a vehicle lateral stability control system, the performance of the driver vehicle road closed loop system through a pylon course slalom test was simulated. The simulation was done in accordance with the GB/T6323.1-94 standard. Vehicle stability control system effectiveness was evaluated by measuring the mean maximum yaw rate and the mean maximum steering wheel angle. The simulation results showed the slalom test value with lateral stability control was approximately 4% higher than without a stability control system. This indicates the controlling system improves vehicle handling stability.  相似文献