CALCULATION OF ULTIMATE STRESS OF UNBONDED PRESTRESSED TENDONS IN UNSYMMETRICAL DEFLECTED BEAMS     

Pan Li Institute of Building Structures  China Academy of Building Research 《保鲜与加工》1989,(3)

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Structure-activity Relationship of Flavonoids Antioxidants     

LIU Jie  WANG Bo-chu  PENG Liang  ZHANG Guang-qiunistry of Education  College of Bioengineering  Chongqing University  Chongqing  Chin 《保鲜与加工》2004,(2):120-124

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Experimental Study on the Deformation Characteristics of Fine-Sandstone Under the Loading and Unloading Conditions     

XU Jiang  WANG Wei-zhong  YANG Xiu-gui  WANG Hongl Disaster Control Engineering Under the State Ministry of Education  Chongqing University  Chongqing  Chin 《保鲜与加工》2004,(12):60-62

The deformation characteristics of the fine-sandstone is studied under the loading and unloading conditions at the three different deformation-rates and the two different stress-levels. The experimental results show that there is really the plastic-loop in the deformation curve for the loading deformation curve is different from the unloading deformation curve. But the plastic-loop is nearly unchangeable since the second circulate loading. The residual-deformation is be almost zero since the second circulate loading, and that the slope of the deformation curve increases as the deformation-rate increases, and that the residual-deformation increases as the stress-levels increases.  相似文献   

Optimization of Worm Gearing''s Geometric Parameters Under the Condition of the Errors and the Load     

XU Wu-jiao  QIN Da-tong  SHI Wan-kai ongqing  Chin 《保鲜与加工》2004,(4):24

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Vibration & Noise Analysis on Double-ring Gear Reducer   总被引：1，自引：0，他引：1  

XIE Yong-chun  WANG Li-hu  LIU Wen  LIU Jing-hao  Chongqing  Chin 《保鲜与加工》2004,(4):20-23

Double-ring gear reducer with Central inputting shaft is studied. The basic structure of reducer as well as testing equipment, probe spot and testing method of Structure-borne noise and air-borne noise is presented. Based on frequency spectrum of each point, amplitude spectrum of structure-borne noise and testing results of air-borne noise, the authors analyze the vibration characters and latent faults of double-ring gear reducer, coming to the value and the cause of the noise, providing theoretical basis for proper design of the double-ring gear reducer and method of reducing its vibration and noise.  相似文献   

Design and Application of a New Elliptical Crystal Spectrometer     

GAO Jie  ZHONG Xian-xin  XIAO Sha-li  XIONG Xian-caieMinistry of Education  Chongqing University  Chongqing  Chin 《保鲜与加工》2004,(5):5-8

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A NEWFANGLED NORMATIVE FORM FOR SINGLE EIGENVALUE SYSTEMS     

Wang Jifeng Dept.of Mechanical  Electrical Engineering 《保鲜与加工》1992,(1)

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PROBABILISTIC EVALUATION FOR STEEL FRAME COLUMNS OF TALL BUILDINGS     

Dai Guoxin  Li Jihu  Xia Zhengzhong Dept.of Civil Engineering 《保鲜与加工》1992,(2)

Based on properties of parameters and test data of dom-estic steel,this paper analyses the reliability and partial coefficient forresistance of steel frame columns of tall builings.The result may serveas a scientific basis.It is not only for domestic steel instead of importedsteel in building tall steel structures,but also for compiling concerendstandards.  相似文献   

Study on DAQ System by Using LabVIEW     

YANG Zhong-ren  RAO Cheng  ZOU Jian  PENG Zhen-liane Ministry of Education  Chongqing  Chin 《保鲜与加工》2004,(2):32-35

Dong village is very valuable for research work because of its special regional and national character and rich cultural implication. In this paper, some information about the location, form and features of Dong village is given. Then, the relationship between the culture and the settlement is analyzed, which provides a clue for understanding Dong village and will be beneficial to creating modern human settlements.  相似文献   

Simulation of the penetration rate (ROP) of the air percussion drilling     

LIN Yuan-hu  LI Run-fang  SHI Tai-he  LIANG Zheng  LIN Teng-jiao Goods  SWPI  ngqing  Chin 《保鲜与加工》2004,(8):1-6

It is difficult to calculate the penetration rate (ROP) of percussion drilling. In the early research, the empirical or semiempirical formulae of the ROP are derived from the laboratory or field data collected by the researchers. However, the ROP value of the formulae is not as accurate as that in the field. Benefiting from the dynamic model, the geometric structure model and the theory of the roller cone bit, the mathematical model of the hammer bit, the mathematical model of the true bottom hole and the mathematical model between the tooth and the rock of the hammer bit are established. Hence the ROP of the air percussion drilling can be predicted by simulation. Field tests show the models are reliable and the results are coincident with that in the field. The research can help to redesign the hammer bit and optimize the drilling parameters.  相似文献