Pressure equipments in the process industries and the newly developing industries usually have extreme sizes and/or are subjected to extreme operating conditions such as high pressure,blast loading,cryogenic temperatu...Pressure equipments in the process industries and the newly developing industries usually have extreme sizes and/or are subjected to extreme operating conditions such as high pressure,blast loading,cryogenic temperature,elevated temperature,complex corrosion,and so on.In order to understand,research and develop these equipments systematically,a concept of extreme pressure equipments（EPEs） is proposed.The applications and demands of EPEs in petrochemical industry,coal chemical industry,advanced energy,military,space technology,and environment protection are introduced.Basic scientific problems in material,design,inspection, and safety related to EPEs are discussed.Then,take chemical composition,manufacturing process,service duration,and operating conditions for example,main factors which affect material properties of EPEs are analyzed.New design concepts including design based on life cycle,dynamic design and light-weight design are introduced.EPEs with higher efficiency,lower cost and safer performance are in urgent demand in national major projects including ten million ton oil refinery,one million ton ethylene,liquefied natural gas transportation,and nuclear power plant.Thus,further research should be conducted on information acquisition, multi-mechanism damage coupling model,damage inspection,life prediction,online safety monitoring,maintenance strategy,safety pre-warning system,and emergency system.展开更多
The basic equations for computing the volume of gas storage tank were derived from the principles of attenuating water hammer pressure. Verifications using experiments indicate that the proposed equation can provide a...The basic equations for computing the volume of gas storage tank were derived from the principles of attenuating water hammer pressure. Verifications using experiments indicate that the proposed equation can provide a fare precision in the predictions. By using the model of solid liquid two phase flow, the gas storage tank, pressure relief valves and slow closure reverse control valves were compared with practical engineering problems, and the functions of gas storage tank in attenuating water hammer pressure were further investigated. [展开更多
We have formulated 3 permissible levels of respiratory resistance for aircraft oxygen equipment in China based on a comprehensive analysis of the results of human pkysiological experiments and feasibility of technolog...We have formulated 3 permissible levels of respiratory resistance for aircraft oxygen equipment in China based on a comprehensive analysis of the results of human pkysiological experiments and feasibility of technological design and performance with reference to existing standards and data. The ideal level can be used as a basic human physiological criterion. The applied permissible level is a criterion that must be followed in the process of design and production. The permissible level during maximum flow rate is presented as an extended allowable criterion for possible exceeding of the stable level for a short time.展开更多
<strong>Objective:</strong> To explore the application of intelligent equipment in non-negative pressure isolation ward for COVID-2019 patients. <strong>Method:</strong> From February 1 to Marc...<strong>Objective:</strong> To explore the application of intelligent equipment in non-negative pressure isolation ward for COVID-2019 patients. <strong>Method:</strong> From February 1 to March 17, 2020, intelligent equipment, such as communication interaction system, intelligent disinfection robot, delivering robot, were used in non- negative pressure isolation ward of COVID-2019. With the help of communication interaction system to supervise the implementation of infection prevention and control, and observe the incorrect situation of pee use and personal behavior before and after the implementation. The disinfection robot and meal delivery robot were used in ward disinfection and life nursing combined with nursing practice. <strong>Result:</strong> Through the supervision of communication interaction system, the frequency of pee use and personal behavior was reduced. The frequency of bad articles before and after improvement was wearing protective clothing (2.80%/0.84%), taking off protective clothing (5.87%/0.84%), personal behavior observation (8.38%/1.90%), P < 0.01. The robot disinfected and delivered medicine for 912.5 h, saving 225 shifts of nursing staff. <strong>Conclusion:</strong> Intelligent equipment is a good option for infection control in isolation ward of COVID-2019. It can not only reduce the workload of health workers, but also the cross-infection.展开更多
In order to find out the contact pressure intensity distribution and its effects on the workepiece flatness error in plane polishing with retaining ring,the contact model and the boundary conditions are built up based...In order to find out the contact pressure intensity distribution and its effects on the workepiece flatness error in plane polishing with retaining ring,the contact model and the boundary conditions are built up based on the axial symmetric elastic contact theory.The pressure intensity distribution is calculated and analyzed with the help of the Hankel transform theory and the constructing solution method of Chebyshev orthogonal polynomials.And then,the effects of the dimensionless ring-workpiece gap,the load ratio of the retaining ring and the dimensionless ring width on the contact pressure intensity distribution are obtained.Finally,based on the distribution theory of material removal volume,the effects of the pressure intensity distributions on the flatness errors of polished workpiece are also investigated experimentally.The results show that the contact pressure intensity distribution becomes more uniform and the better profile of polished workpiece can also be obtained,if the dimensionless ring-workpiece gap is reduced,the load ratio is selected as 0.6 to 0.85,and the dimensionless ring width is taken as 0.13 to 0.40.展开更多
基金supported by National Hi-tech Research and Development Program of China(863 Program,Grant No. 2009AA044801)
文摘Pressure equipments in the process industries and the newly developing industries usually have extreme sizes and/or are subjected to extreme operating conditions such as high pressure,blast loading,cryogenic temperature,elevated temperature,complex corrosion,and so on.In order to understand,research and develop these equipments systematically,a concept of extreme pressure equipments（EPEs） is proposed.The applications and demands of EPEs in petrochemical industry,coal chemical industry,advanced energy,military,space technology,and environment protection are introduced.Basic scientific problems in material,design,inspection, and safety related to EPEs are discussed.Then,take chemical composition,manufacturing process,service duration,and operating conditions for example,main factors which affect material properties of EPEs are analyzed.New design concepts including design based on life cycle,dynamic design and light-weight design are introduced.EPEs with higher efficiency,lower cost and safer performance are in urgent demand in national major projects including ten million ton oil refinery,one million ton ethylene,liquefied natural gas transportation,and nuclear power plant.Thus,further research should be conducted on information acquisition, multi-mechanism damage coupling model,damage inspection,life prediction,online safety monitoring,maintenance strategy,safety pre-warning system,and emergency system.
文摘The basic equations for computing the volume of gas storage tank were derived from the principles of attenuating water hammer pressure. Verifications using experiments indicate that the proposed equation can provide a fare precision in the predictions. By using the model of solid liquid two phase flow, the gas storage tank, pressure relief valves and slow closure reverse control valves were compared with practical engineering problems, and the functions of gas storage tank in attenuating water hammer pressure were further investigated. [
文摘We have formulated 3 permissible levels of respiratory resistance for aircraft oxygen equipment in China based on a comprehensive analysis of the results of human pkysiological experiments and feasibility of technological design and performance with reference to existing standards and data. The ideal level can be used as a basic human physiological criterion. The applied permissible level is a criterion that must be followed in the process of design and production. The permissible level during maximum flow rate is presented as an extended allowable criterion for possible exceeding of the stable level for a short time.
文摘<strong>Objective:</strong> To explore the application of intelligent equipment in non-negative pressure isolation ward for COVID-2019 patients. <strong>Method:</strong> From February 1 to March 17, 2020, intelligent equipment, such as communication interaction system, intelligent disinfection robot, delivering robot, were used in non- negative pressure isolation ward of COVID-2019. With the help of communication interaction system to supervise the implementation of infection prevention and control, and observe the incorrect situation of pee use and personal behavior before and after the implementation. The disinfection robot and meal delivery robot were used in ward disinfection and life nursing combined with nursing practice. <strong>Result:</strong> Through the supervision of communication interaction system, the frequency of pee use and personal behavior was reduced. The frequency of bad articles before and after improvement was wearing protective clothing (2.80%/0.84%), taking off protective clothing (5.87%/0.84%), personal behavior observation (8.38%/1.90%), P < 0.01. The robot disinfected and delivered medicine for 912.5 h, saving 225 shifts of nursing staff. <strong>Conclusion:</strong> Intelligent equipment is a good option for infection control in isolation ward of COVID-2019. It can not only reduce the workload of health workers, but also the cross-infection.
基金Sponsored by the National Nature Science Foundation of China (50875179)
文摘In order to find out the contact pressure intensity distribution and its effects on the workepiece flatness error in plane polishing with retaining ring,the contact model and the boundary conditions are built up based on the axial symmetric elastic contact theory.The pressure intensity distribution is calculated and analyzed with the help of the Hankel transform theory and the constructing solution method of Chebyshev orthogonal polynomials.And then,the effects of the dimensionless ring-workpiece gap,the load ratio of the retaining ring and the dimensionless ring width on the contact pressure intensity distribution are obtained.Finally,based on the distribution theory of material removal volume,the effects of the pressure intensity distributions on the flatness errors of polished workpiece are also investigated experimentally.The results show that the contact pressure intensity distribution becomes more uniform and the better profile of polished workpiece can also be obtained,if the dimensionless ring-workpiece gap is reduced,the load ratio is selected as 0.6 to 0.85,and the dimensionless ring width is taken as 0.13 to 0.40.
