Acrylic acid was graft-copolymerized onto Rhi. oryzae's cell wall structural polysaccharide directly and efficiently in aqueous solution with eerie ammonium nitrate as initiator. The maximal grafting percentage of...Acrylic acid was graft-copolymerized onto Rhi. oryzae's cell wall structural polysaccharide directly and efficiently in aqueous solution with eerie ammonium nitrate as initiator. The maximal grafting percentage of 135.5% was obtained under the condition of [Ce4+]=5mmol·L-1, [AA]=lmol·L-1, T=60℃ and t=3h. Graft copolymerization was suggested to proceed through free radical reaction mechanism. Grafting occurred primarily on chitosan. Acrylic acid was also attempted to be grafted onto Asp. niger cell wall structural polysaccharide, and only 44.2% of grafting percentage was resulted.展开更多
World Steel Demand Forecast to Grow by 7.3 % in 2006;China＇s Steel Production in April 2006：33,711,100 tons;China＇s Steel Product Prices Recovering from Slump;The Profits of Steel Industry Dropped 74.6 %;Refractory...World Steel Demand Forecast to Grow by 7.3 % in 2006;China＇s Steel Production in April 2006：33,711,100 tons;China＇s Steel Product Prices Recovering from Slump;The Profits of Steel Industry Dropped 74.6 %;Refractory Companies Attack EU Rulings;Steel to Lose Tax Rebates;展开更多
As a basic property of cloud,accurate identification of cloud type is useful in forecasting the evolution of landfalling typhoons.Millimeter-wave cloud radar is an important means of identifying cloud type.Here,we dev...As a basic property of cloud,accurate identification of cloud type is useful in forecasting the evolution of landfalling typhoons.Millimeter-wave cloud radar is an important means of identifying cloud type.Here,we develop a fuzzy logic algorithm that depends on radar range-height-indicator(RHI)data and takes into account the fundamental physical features of different cloud types.The algorithm is applied to a ground-based Ka-band millimeter-wave cloud radar.The input parameters of the algorithm include average reflectivity factor intensity,ellipse long axis orientation,cloud base height,cloud thickness,presence/absence of precipitation,ratio of horizontal extent to vertical extent,maximum echo intensity,and standard variance of intensities.The identified cloud types are stratus(St),stratocumulus(Sc),cumulus(Cu),cumulonimbus(Cb),nimbostratus(Ns),altostratus(As),altocumulus(Ac)and high cloud.The cloud types identified using the algorithm are in good agreement with those identified by a human observer.As a case study,the algorithm was applied to typhoon Khanun(1720),which made landfall in south-eastern China in October 2017.Sequential identification results from the algorithm clearly reflected changes in cloud type and provided indicative information for forecasting of the typhoon.展开更多
Squall line is a kind of common mesoscale disaster weather.At present,there are few studies on the elaborate detection of squall line by dual polarization radar.With the dual polarization upgrade of weather radar netw...Squall line is a kind of common mesoscale disaster weather.At present,there are few studies on the elaborate detection of squall line by dual polarization radar.With the dual polarization upgrade of weather radar network,we need to study the relationship between squall line echoes of base data and polarization data to reveal new echo phenomena and formation mechanisms.The relationship between radar parameters and atmospheric physical processes also need to be examined.Based on the NUIST CDP radar,a squall line in the Yangtze and Huaihe River basin that occurred from July 30 to 31,2014 is analyzed.The results show that polarization parameters have obvious advantages in the characteristics analysis of size,phase state,shape and orientation of the water condensate particles.The phase states of water condensate particles in convection cell can be distinguished through comparative discussion.Several phase states exist in the squall line,including small,medium and large raindrops,melting hails,dry hails and ice crystal particles and the Z_(DR)column can be used to identify the location of the main updraft.In addition,the polarization parameters are more sensitive to the melting layer.The gust front is presented as a narrow linear echo in Z affected by strong turbulence.It is an obvious velocity convergence line in V and approximately 0.70 inρ_(HV).The Z_(DR)can be used as a criterion to distinguish the horizontal and vertical scale of turbulence.The deforming turbulence,which is affected by environmental airflow,will cause an abnormally high Z_(DR)in the gust front and a negative Z_(DR)before and after the gust front.The variation of Z_(DR)depends on the turbulence arrangement,orientation and relative position between turbulence and radar.These dual polarization parameter characteristics offer insights into understanding the structure and evolution of the squall line.展开更多
基金the National Natural Science Foundation of China (No. 29606009).
文摘Acrylic acid was graft-copolymerized onto Rhi. oryzae's cell wall structural polysaccharide directly and efficiently in aqueous solution with eerie ammonium nitrate as initiator. The maximal grafting percentage of 135.5% was obtained under the condition of [Ce4+]=5mmol·L-1, [AA]=lmol·L-1, T=60℃ and t=3h. Graft copolymerization was suggested to proceed through free radical reaction mechanism. Grafting occurred primarily on chitosan. Acrylic acid was also attempted to be grafted onto Asp. niger cell wall structural polysaccharide, and only 44.2% of grafting percentage was resulted.
文摘World Steel Demand Forecast to Grow by 7.3 % in 2006;China＇s Steel Production in April 2006：33,711,100 tons;China＇s Steel Product Prices Recovering from Slump;The Profits of Steel Industry Dropped 74.6 %;Refractory Companies Attack EU Rulings;Steel to Lose Tax Rebates;
基金This work was supported by the National Natural Science Foundation of China(Grant No.41675029)the National Basic Research Program of China(No.2013CB430102).
文摘As a basic property of cloud,accurate identification of cloud type is useful in forecasting the evolution of landfalling typhoons.Millimeter-wave cloud radar is an important means of identifying cloud type.Here,we develop a fuzzy logic algorithm that depends on radar range-height-indicator(RHI)data and takes into account the fundamental physical features of different cloud types.The algorithm is applied to a ground-based Ka-band millimeter-wave cloud radar.The input parameters of the algorithm include average reflectivity factor intensity,ellipse long axis orientation,cloud base height,cloud thickness,presence/absence of precipitation,ratio of horizontal extent to vertical extent,maximum echo intensity,and standard variance of intensities.The identified cloud types are stratus(St),stratocumulus(Sc),cumulus(Cu),cumulonimbus(Cb),nimbostratus(Ns),altostratus(As),altocumulus(Ac)and high cloud.The cloud types identified using the algorithm are in good agreement with those identified by a human observer.As a case study,the algorithm was applied to typhoon Khanun(1720),which made landfall in south-eastern China in October 2017.Sequential identification results from the algorithm clearly reflected changes in cloud type and provided indicative information for forecasting of the typhoon.
基金This work was supported by the National Natural Science Foundation of China(Grant No.41675029)the Natural Science Foundation of Shandong Province(Nos.ZR2020MD052 and ZR2020MD053)the Shanghai Aerospace Science and Technology Innovation Fund Project(No.SAST2019-097).
文摘Squall line is a kind of common mesoscale disaster weather.At present,there are few studies on the elaborate detection of squall line by dual polarization radar.With the dual polarization upgrade of weather radar network,we need to study the relationship between squall line echoes of base data and polarization data to reveal new echo phenomena and formation mechanisms.The relationship between radar parameters and atmospheric physical processes also need to be examined.Based on the NUIST CDP radar,a squall line in the Yangtze and Huaihe River basin that occurred from July 30 to 31,2014 is analyzed.The results show that polarization parameters have obvious advantages in the characteristics analysis of size,phase state,shape and orientation of the water condensate particles.The phase states of water condensate particles in convection cell can be distinguished through comparative discussion.Several phase states exist in the squall line,including small,medium and large raindrops,melting hails,dry hails and ice crystal particles and the Z_(DR)column can be used to identify the location of the main updraft.In addition,the polarization parameters are more sensitive to the melting layer.The gust front is presented as a narrow linear echo in Z affected by strong turbulence.It is an obvious velocity convergence line in V and approximately 0.70 inρ_(HV).The Z_(DR)can be used as a criterion to distinguish the horizontal and vertical scale of turbulence.The deforming turbulence,which is affected by environmental airflow,will cause an abnormally high Z_(DR)in the gust front and a negative Z_(DR)before and after the gust front.The variation of Z_(DR)depends on the turbulence arrangement,orientation and relative position between turbulence and radar.These dual polarization parameter characteristics offer insights into understanding the structure and evolution of the squall line.
