The fiber quality status is very important for super quality cotton production and diverse requirements of textile industry in China.In this study,the quality of cotton fiber samples which are collected from 13 major ...The fiber quality status is very important for super quality cotton production and diverse requirements of textile industry in China.In this study,the quality of cotton fiber samples which are collected from 13 major cotton production provinces between 2001 to 2005 were analyzed.Eight quality展开更多
During the 2012 Lanzhou International Marathon, the local government made a significant effort to improve traffic conditions and air quality by implementing traffic restriction measures. To evaluate the direct effect ...During the 2012 Lanzhou International Marathon, the local government made a significant effort to improve traffic conditions and air quality by implementing traffic restriction measures. To evaluate the direct effect of these measures on urban air quality, especially particle concentrations and their size distributions, atmospheric particle size distributions (0.5-20μm) obtained using an aerodynamic particle sizer (model 3321, TSI, USA) in June 2012 were analyzed. It was found that the particle number, surface area and volume concentrations for size range 0.5-10 μm were (15.0±2.1) cm-3, (11.8±2.6) μm2/cm3 and (1.9±0.6) μm2/cm3, respectively, on the traffic-restricted day (Sunday), which is 63.2%, 53.0% and 47.2% lower than those on a normal Sunday. For number and surface area concentrations, the most affected size range was 0.5-0.7 and 0.5-0.8 μm, respectively, while for volume concentration, the most affected size ranges were 0.5-0.8, 1.7-2.0 and 5.0-5.4 μm. Number and volume concentrations of particles in size range 0.5-1.0μm correlated well with the number of non-CNG (Compressed Natural Gas) powered vehicles, while their correlation with the number of CNG-powered vehicles was very low, suggesting that reasonable urban traffic controls along with vehicle technology improvements could play an important role in improving urban air quality.展开更多
Based on the global distribution of land and soil quality and the world population,future trends in the agricultural use of land and soil resources are described,which will severely compromise future global food and f...Based on the global distribution of land and soil quality and the world population,future trends in the agricultural use of land and soil resources are described,which will severely compromise future global food and fiber production through the increase and the spatial changes of world population,through the loss of fertile land caused by insufficient soil management and through urbanisation and industrialization Moreover,future changes in life style and the increasing demand for food and bioenergy,trough changes in world economy,through climate change and a worldwide decrease in fresh water supply,sustainable land use for the production of food and fiber will be under threat.Until 2050 global food production must be doubled for satisfying global needs.Our scenarios should help to preview future changes,to counterbalance and to mitigate possible negative impacts,thus sustaining global food security.展开更多
文摘The fiber quality status is very important for super quality cotton production and diverse requirements of textile industry in China.In this study,the quality of cotton fiber samples which are collected from 13 major cotton production provinces between 2001 to 2005 were analyzed.Eight quality
基金supported by the Hundred Talents Program of Chinese Academy of Sciences (No. 29O827631)
文摘During the 2012 Lanzhou International Marathon, the local government made a significant effort to improve traffic conditions and air quality by implementing traffic restriction measures. To evaluate the direct effect of these measures on urban air quality, especially particle concentrations and their size distributions, atmospheric particle size distributions (0.5-20μm) obtained using an aerodynamic particle sizer (model 3321, TSI, USA) in June 2012 were analyzed. It was found that the particle number, surface area and volume concentrations for size range 0.5-10 μm were (15.0±2.1) cm-3, (11.8±2.6) μm2/cm3 and (1.9±0.6) μm2/cm3, respectively, on the traffic-restricted day (Sunday), which is 63.2%, 53.0% and 47.2% lower than those on a normal Sunday. For number and surface area concentrations, the most affected size range was 0.5-0.7 and 0.5-0.8 μm, respectively, while for volume concentration, the most affected size ranges were 0.5-0.8, 1.7-2.0 and 5.0-5.4 μm. Number and volume concentrations of particles in size range 0.5-1.0μm correlated well with the number of non-CNG (Compressed Natural Gas) powered vehicles, while their correlation with the number of CNG-powered vehicles was very low, suggesting that reasonable urban traffic controls along with vehicle technology improvements could play an important role in improving urban air quality.
文摘Based on the global distribution of land and soil quality and the world population,future trends in the agricultural use of land and soil resources are described,which will severely compromise future global food and fiber production through the increase and the spatial changes of world population,through the loss of fertile land caused by insufficient soil management and through urbanisation and industrialization Moreover,future changes in life style and the increasing demand for food and bioenergy,trough changes in world economy,through climate change and a worldwide decrease in fresh water supply,sustainable land use for the production of food and fiber will be under threat.Until 2050 global food production must be doubled for satisfying global needs.Our scenarios should help to preview future changes,to counterbalance and to mitigate possible negative impacts,thus sustaining global food security.