Based on the research on the diffusion of suspended sediments discharged outside of Yangtze River estuary and the landuse of Shanghai using Landsat MSS images in several years, the authors analysed the characteristics...Based on the research on the diffusion of suspended sediments discharged outside of Yangtze River estuary and the landuse of Shanghai using Landsat MSS images in several years, the authors analysed the characteristics of TM CCT data of Shanghai scene, pointed out concrete range of maximum turbidity and growth of urban boundary of Shanghai through the information extraction.The feature vector combination method is used in the research process. The result is getting nice.展开更多
Hydrologic process,turbidity,suspended particles matters(SPM),major cations and TOC concentrations during two storm events in late April 2008 were monitored at Jiangjia Spring which is the outlet of Qingmuguan undergr...Hydrologic process,turbidity,suspended particles matters(SPM),major cations and TOC concentrations during two storm events in late April 2008 were monitored at Jiangjia Spring which is the outlet of Qingmuguan underground river system.Scanning electron microscopy(SEM) and energy disperse spectroscopy(EDS) analyses of SPM were展开更多
The effects of heat treatment(heating temperature and pH) on the structures and emulsifying properties of caseins were systematically studied by spectroscopy.Heat treatment from 60to 100℃resulted in an increase in th...The effects of heat treatment(heating temperature and pH) on the structures and emulsifying properties of caseins were systematically studied by spectroscopy.Heat treatment from 60to 100℃resulted in an increase in their fluorescence intensity,hydrodynamic diameter,turbidity and emulsifying activity index,but decreased the size polydispersity of caseins.In the pH range of 5.5to 7.0,the fluorescence intensity,hydrodynamic diameter,turbidity and emulsifying properties decreased with increased heating pH,but the size polydispersity of caseins increased with increased pH.The relationship between the surface fluorescence intensity and emulsifying activity was also investigated,revealing a correlation coefficient of 0.90.These results suggested that heat treatment could be used to modify the structures and emulsifying properties of caseins by appropriately selecting heating conditions.展开更多
Petroleum based oils,the so-called mineral oils,are used for impregnating solid insulations or filling products of very large number of electric materials:transformers,reactors,cables,bushings,circuit breakers,tap cha...Petroleum based oils,the so-called mineral oils,are used for impregnating solid insulations or filling products of very large number of electric materials:transformers,reactors,cables,bushings,circuit breakers,tap changers, etc.In these equipments,oil is exposed to electrical stress and may experience electrical discharges under certain circumstances.Since the electrical stress is unavoidable in power equipments,the ability of oil to resist decomposition under electrical stress is of great importance for the safety of these devices.Electrical stress together with heat and moisture,in the presence of oxygen,oxidises the oil producing free radicals,acids and sludge that are deleterious to the transformer.In this paper,the effect of electrical discharges on oil properties is reported.The results indicate that quality of oil is considerably affected with increasing voltage stress.Comparing oil properties before and after voltage application allows assessing the outcome of random secondary chemical reactions between large oil born free radicals.展开更多
Since the suspended sediments have severe influence on acoustic radiated field of transducer,it is significant for sonar system to analyze the influence of suspended sediments on acoustic pressure in the seafloor mini...Since the suspended sediments have severe influence on acoustic radiated field of transducer,it is significant for sonar system to analyze the influence of suspended sediments on acoustic pressure in the seafloor mining environment.Based on the KZK(Khokhlov-Zabolotkaya-Kuznetsov)equation,the method of sound field analysis in turbid water is proposed.Firstly,based on the analysis of absorption in clean water and viscous absorption of suspended sediments,the sound attenuation coefficient as a function of frequency in the mining environment is calculated.Then,based on the solution of KZK equation in frequency domain,the axial sound pressure of transducer in clear water as well as turbid water is simulated using MATLAB.Simulation results show that the influence of the suspended sediments on the pressure of near field is negligible.With the increase of distance,the axial sound pressures of transducer decay rapidly.Suspended sediments seriously affect the pressure in far-field.To verify the validity of this numerical method,experiment is designed and the axial sound pressure of transducer with a frequency of 200 kHz and a beam width of 7.5~is measured in simulated mining experiment.The results show that the simulation results agree well with the experiments,and the KZK equation can be used to calculate the sound field in turbid water.展开更多
文摘Based on the research on the diffusion of suspended sediments discharged outside of Yangtze River estuary and the landuse of Shanghai using Landsat MSS images in several years, the authors analysed the characteristics of TM CCT data of Shanghai scene, pointed out concrete range of maximum turbidity and growth of urban boundary of Shanghai through the information extraction.The feature vector combination method is used in the research process. The result is getting nice.
文摘Hydrologic process,turbidity,suspended particles matters(SPM),major cations and TOC concentrations during two storm events in late April 2008 were monitored at Jiangjia Spring which is the outlet of Qingmuguan underground river system.Scanning electron microscopy(SEM) and energy disperse spectroscopy(EDS) analyses of SPM were
基金International Science&Technology Cooperation Program of China(2011DFA32550)Ministry of Science and Technology of China(2012BAD12B08)
文摘The effects of heat treatment(heating temperature and pH) on the structures and emulsifying properties of caseins were systematically studied by spectroscopy.Heat treatment from 60to 100℃resulted in an increase in their fluorescence intensity,hydrodynamic diameter,turbidity and emulsifying activity index,but decreased the size polydispersity of caseins.In the pH range of 5.5to 7.0,the fluorescence intensity,hydrodynamic diameter,turbidity and emulsifying properties decreased with increased heating pH,but the size polydispersity of caseins increased with increased pH.The relationship between the surface fluorescence intensity and emulsifying activity was also investigated,revealing a correlation coefficient of 0.90.These results suggested that heat treatment could be used to modify the structures and emulsifying properties of caseins by appropriately selecting heating conditions.
文摘Petroleum based oils,the so-called mineral oils,are used for impregnating solid insulations or filling products of very large number of electric materials:transformers,reactors,cables,bushings,circuit breakers,tap changers, etc.In these equipments,oil is exposed to electrical stress and may experience electrical discharges under certain circumstances.Since the electrical stress is unavoidable in power equipments,the ability of oil to resist decomposition under electrical stress is of great importance for the safety of these devices.Electrical stress together with heat and moisture,in the presence of oxygen,oxidises the oil producing free radicals,acids and sludge that are deleterious to the transformer.In this paper,the effect of electrical discharges on oil properties is reported.The results indicate that quality of oil is considerably affected with increasing voltage stress.Comparing oil properties before and after voltage application allows assessing the outcome of random secondary chemical reactions between large oil born free radicals.
基金Project(51374245)supported by the National Natural Science Foundation of ChinaProject(10C0681)supported by Education Department of Hunan Province,China
文摘Since the suspended sediments have severe influence on acoustic radiated field of transducer,it is significant for sonar system to analyze the influence of suspended sediments on acoustic pressure in the seafloor mining environment.Based on the KZK(Khokhlov-Zabolotkaya-Kuznetsov)equation,the method of sound field analysis in turbid water is proposed.Firstly,based on the analysis of absorption in clean water and viscous absorption of suspended sediments,the sound attenuation coefficient as a function of frequency in the mining environment is calculated.Then,based on the solution of KZK equation in frequency domain,the axial sound pressure of transducer in clear water as well as turbid water is simulated using MATLAB.Simulation results show that the influence of the suspended sediments on the pressure of near field is negligible.With the increase of distance,the axial sound pressures of transducer decay rapidly.Suspended sediments seriously affect the pressure in far-field.To verify the validity of this numerical method,experiment is designed and the axial sound pressure of transducer with a frequency of 200 kHz and a beam width of 7.5~is measured in simulated mining experiment.The results show that the simulation results agree well with the experiments,and the KZK equation can be used to calculate the sound field in turbid water.
