This study aimed to conduct statistical analysis of temperature,relative humidity,wind direction,wind velocity,deep ground temperature and other related data from National Meteorological Observing Station of Hejian Ci...This study aimed to conduct statistical analysis of temperature,relative humidity,wind direction,wind velocity,deep ground temperature and other related data from National Meteorological Observing Station of Hejian City in 2012.According to the results,observation data varied due to different instruments and equipments,surrounding environments and underlying surface properties.The difference value of monthly average temperature between new site and old site ranged from-0.5 to 0 ℃; the difference value of monthly average maximum temperature ranged from-0.4 to 0.2 ℃; the difference value of monthly average minimum temperature ranged from-0.8 to 0 ℃; the difference value of monthly extreme maximum temperature ranged from-1.1 to 0.6 ℃; the difference value of monthly extreme minimum temperature ranged from-1.2 to 0.3 ℃.Annual average temperature,annual average maximum temperature and annual average minimum temperature in new site were lower than those in old site; annual extreme maximum temperature in new site was higher than that in old site; annual extreme minimum temperature in new site was lower than that in old site.The difference value of monthly average relative humidity between new site and old site ranged from 2％ to 6％; the difference value of monthly minimum relative humidity ranged from-4％ to 5％.Annual minimum relative humidity in new site was consistent with that in old site.The difference value of 2 min average wind velocity between new site and old site ranged from-0.1 to 0.4 m/s; the difference value of monthly maximum wind velocity ranged from-1.2 to 2.2 m/s; the difference value of monthly extreme wind velocity ranged from-2.0 to 2.8 m/s.Annual maximum wind velocity in new site was basically consistent with that in old site; annual extreme wind velocity in new site was significantly higher than that in old site; annual wind direction frequency in new site was lower than that in old site; annual most frequent wind direction in new site was S and that in old site was SSW.The difference value of average temperature at the depth of 40 cm ranged from-1.1 to 2.5 ℃; the difference value of average temperature at the depth of 80 cm ranged from-2.4 to 2.1 ℃; the difference value of average temperature at the depth of 160 cm ranged from-2.5 to 2.7 ℃; the difference value of average temperature at the depth of 320 cm ranged from-1.6 to 1.1 ℃.Annual average temperatures at the depths of 40 and 160 cm in new site were higher than those in old site,while annual average temperatures at the depths of 80 and 320 cm in new site were lower than those in old site.This paper provided certain correction stand for the use of observation data from new and old sites.展开更多
Equilibrium moisture content （EMC） data for rough rice of thirteen Chinese varieties were obtained by static gravimetric method at five different temperatures （10, 20, 25, 30, and 35 ℃） and 11% to 96% equilibrium...Equilibrium moisture content （EMC） data for rough rice of thirteen Chinese varieties were obtained by static gravimetric method at five different temperatures （10, 20, 25, 30, and 35 ℃） and 11% to 96% equilibrium relative humidity （ERH）. Six models, i.e., Brunauer-Emmett-Teller, Guggenheim-Anderson-deBoer, Modified Chung-Pfost （MCPE）, Modified Henderson, Modified Oswin, and Strohman-Yoerger （STYE） fitted the EMC/ERH data based on the coefficient of determination, residue sum-of-squares, standard error of estimate, and mean relative percent error. The best fitted equations were MCPE and STYE, but MCPE is three-parameter, readily transformed equation and adopted in this study. The isosteric heats for both rough rice desorption and adsorption, and for both the sorption of Japonica and Indica rice, decreased rapidly with an increase in seed moisture content （m.c.） until the m.c. of 20% dry basis （d.b.） reached, and thereafter they decreased smoothly with increasing moisture content. The isosteric heats of rough rice desorption were higher than those of adsorption below the m.c. of 22.5% d.b., but thereafter, there was no significant difference found between desorption and adsorption. The sorption isosteric heats of Indica rice were slightly higher than those of Japonica rice under all moisture contents at a constant temperature. These results provide a sound basis for future work on the drying and storage of rice.展开更多
文摘This study aimed to conduct statistical analysis of temperature,relative humidity,wind direction,wind velocity,deep ground temperature and other related data from National Meteorological Observing Station of Hejian City in 2012.According to the results,observation data varied due to different instruments and equipments,surrounding environments and underlying surface properties.The difference value of monthly average temperature between new site and old site ranged from-0.5 to 0 ℃; the difference value of monthly average maximum temperature ranged from-0.4 to 0.2 ℃; the difference value of monthly average minimum temperature ranged from-0.8 to 0 ℃; the difference value of monthly extreme maximum temperature ranged from-1.1 to 0.6 ℃; the difference value of monthly extreme minimum temperature ranged from-1.2 to 0.3 ℃.Annual average temperature,annual average maximum temperature and annual average minimum temperature in new site were lower than those in old site; annual extreme maximum temperature in new site was higher than that in old site; annual extreme minimum temperature in new site was lower than that in old site.The difference value of monthly average relative humidity between new site and old site ranged from 2％ to 6％; the difference value of monthly minimum relative humidity ranged from-4％ to 5％.Annual minimum relative humidity in new site was consistent with that in old site.The difference value of 2 min average wind velocity between new site and old site ranged from-0.1 to 0.4 m/s; the difference value of monthly maximum wind velocity ranged from-1.2 to 2.2 m/s; the difference value of monthly extreme wind velocity ranged from-2.0 to 2.8 m/s.Annual maximum wind velocity in new site was basically consistent with that in old site; annual extreme wind velocity in new site was significantly higher than that in old site; annual wind direction frequency in new site was lower than that in old site; annual most frequent wind direction in new site was S and that in old site was SSW.The difference value of average temperature at the depth of 40 cm ranged from-1.1 to 2.5 ℃; the difference value of average temperature at the depth of 80 cm ranged from-2.4 to 2.1 ℃; the difference value of average temperature at the depth of 160 cm ranged from-2.5 to 2.7 ℃; the difference value of average temperature at the depth of 320 cm ranged from-1.6 to 1.1 ℃.Annual average temperatures at the depths of 40 and 160 cm in new site were higher than those in old site,while annual average temperatures at the depths of 80 and 320 cm in new site were lower than those in old site.This paper provided certain correction stand for the use of observation data from new and old sites.
文摘Equilibrium moisture content （EMC） data for rough rice of thirteen Chinese varieties were obtained by static gravimetric method at five different temperatures （10, 20, 25, 30, and 35 ℃） and 11% to 96% equilibrium relative humidity （ERH）. Six models, i.e., Brunauer-Emmett-Teller, Guggenheim-Anderson-deBoer, Modified Chung-Pfost （MCPE）, Modified Henderson, Modified Oswin, and Strohman-Yoerger （STYE） fitted the EMC/ERH data based on the coefficient of determination, residue sum-of-squares, standard error of estimate, and mean relative percent error. The best fitted equations were MCPE and STYE, but MCPE is three-parameter, readily transformed equation and adopted in this study. The isosteric heats for both rough rice desorption and adsorption, and for both the sorption of Japonica and Indica rice, decreased rapidly with an increase in seed moisture content （m.c.） until the m.c. of 20% dry basis （d.b.） reached, and thereafter they decreased smoothly with increasing moisture content. The isosteric heats of rough rice desorption were higher than those of adsorption below the m.c. of 22.5% d.b., but thereafter, there was no significant difference found between desorption and adsorption. The sorption isosteric heats of Indica rice were slightly higher than those of Japonica rice under all moisture contents at a constant temperature. These results provide a sound basis for future work on the drying and storage of rice.
