In Japan, floods occur frequently in urban areas because non-infiltrating areas are seeing increased urbanization. To prevent floods, urban basins must improve the infiltration capacity and water retention of the whol...In Japan, floods occur frequently in urban areas because non-infiltrating areas are seeing increased urbanization. To prevent floods, urban basins must improve the infiltration capacity and water retention of the whole basin. There are several basic technologies for river basin management, such as infiltration trenches or rainwater storage. However, a method of soil amendment that prevents flood disasters has not been established. This study aims to evaluate the infiltration capacity of soil amendments using bamboo charcoal and humus. A constant-head infiltration test and rainfall simulation were conducted to evaluate the properties of the soil amendments. The constant-head infiltration test＇s results showed that soils mixed with 30% humus had the greatest potential for influencing initial and final infiltration rates, and the more the mixing rates of bamboo charcoal and humus were increased, the higher the water retention capacity. The results of the rainfall simulation showed that soils mixed with 30% humus had the highest final infiltration rates and lowest multiplication spillage. To reduce the runoff volume using soil amendment technology, it is important to delay overland flow, and the hydraulic properties of the soils mixed with bamboo charcoal and humus were as effective as those of granite soils.展开更多
According to the Researches on Coal Development Strategies in China (1991 ~ 2020),the production scale of coal in China will increase to 2100 Mt in the year 2020 and the district layout of coal development and product...According to the Researches on Coal Development Strategies in China (1991 ~ 2020),the production scale of coal in China will increase to 2100 Mt in the year 2020 and the district layout of coal development and production will be diverted from the east to the central-west step by step. In addit1on, the multi-ply runnning struc ture-mines of the nation,the local and the village and town combined with produc tion scales of the large, the middle,and the small-will be kept. However,the tech nique of mining will be improved greatly.展开更多
An improved spherical, movable transfer skirt for autonomous submersibles has been devised. It was designed to permit the transfer of equipment and personnel from a submersible to the pressure chamber of an oil storag...An improved spherical, movable transfer skirt for autonomous submersibles has been devised. It was designed to permit the transfer of equipment and personnel from a submersible to the pressure chamber of an oil storage sea-bed structure. It also allowed mating at large vertical angles while the submersible remained horizontal. Seal failure modes and procedures for analyzing the sealing ability of the mating flange of the hull transfer skirt were thoroughly analyzed using conservative estimation methods. In the analysis, sea currents and mating angles were considered. Results showed that when considering the effects of currents, spherical radius and mating angle, their influence on seal ring failure should be considered first. The critical mating depth for a seal ring failure was larger than for either sliding or rotational failure modes. The critical mating depth can be used to determine the mating method of the submersible. The analytical procedures and results can be used as a reference for the design of spherical hull transfer skirts.展开更多
The authors once made a preliminary research on population carrying capacity of the land in the Economic Area of Zhujiang Delta (EAZD for short) in 1995, and reckoned that the ultimate population in this region will b...The authors once made a preliminary research on population carrying capacity of the land in the Economic Area of Zhujiang Delta (EAZD for short) in 1995, and reckoned that the ultimate population in this region will be 23 550 thousand by year of 2000. While the population in being in EAZD was 22.62 million in 1999.This accords with the prefigured result in the rough from the point of view of development. According to the data of plow land resources from the 2000 Statistical Yearbook of EAZD and the study on the population-foodstuff-plow land relationship, this paper calculates the productive potential of plow land and the population carrying capacity of land by year of 2010, and puts forward the countermeasures for improving the population carrying capacity of land in this region.展开更多
The paper presents the measurement campaign of wind energy potential undertaken in Republic of Macedonia on four sites from the middle of 2006. The wind data analysis has been performed for one site, following with th...The paper presents the measurement campaign of wind energy potential undertaken in Republic of Macedonia on four sites from the middle of 2006. The wind data analysis has been performed for one site, following with the assessment of energy production of simulated wind park with six wind turbine generators.展开更多
Generative resources are mainly derived from the students （sometimes from the teachers）, which is dynamically generated in the students＇ practice, self-inquiry, and cooperative communication. Gifted children refer ...Generative resources are mainly derived from the students （sometimes from the teachers）, which is dynamically generated in the students＇ practice, self-inquiry, and cooperative communication. Gifted children refer to a group of children who have such characteristics as high IQ （intelligence quotient）, strong creativity, and good personality. Their intelligence and capability have great potential for further development. As cognitive ability is one of the prominent characteristics of supernormal children, the lecturers can not only pay attention to teaching knowledge （facts teaching）, but also need provide proper opportunities for them to develop their aggressiveness, creativities, and challenges when teaching these children. Because students are active in thinking, in the classroom, students often have some unexpected ideas, that is, the generation of the classroom, in the face of this situation, teachers should be how to do？ A joke between students in the class, sparked the interest of a classmate, and then under the teachers＇ guidance, they invented a chemistry experiment instrument Ω type pipe, illustrated the importance of the teachers focus on creating teaching.展开更多
Energy crops are a basic material in the bioenergy industry, and they can also mitigate carbon emissions and have environ- mental benefits when planted on marginal lands. The aim of this study was to evaluate the pote...Energy crops are a basic material in the bioenergy industry, and they can also mitigate carbon emissions and have environ- mental benefits when planted on marginal lands. The aim of this study was to evaluate the potential productivity of energy crops on marginal lands in China. A mechanistic model, combined with energy crop and land use characteristics, and meteorological and soil parameters, was used to simulate the potential productivity of energy crops. There were three main results. 1） The total marginal land in China was determined to be 104.78 × 106 ha. The 400-mm precipitation boundary line, which is the dividing line between the semi-humid and semi-arid zones in China, also divided the marginal land into shrub land and sparse forest land in the southeast and bare land, bare rock land, and saline alkali land in the northeast. 2） The total area of the marginal land suitable for planting energy crops was determined to be 55.82 × 106 ha, with Xanthoceras sorbifolia and Cerasus humilis mainly grown in the northern China, Jatropha curcas and Comus wilsoniana mainly grown in the southwest and southeast, and Pistacia chinensis mainly grown in the central area, while also having a northeast-southwest zonal distribution. 3） Taking the highest yield in overlapping areas, the potential productivity of target energy crops was determined to be 32.63 × 106 t/yr. Without considering the overlapping areas, the potential productivity was 6.81× 106 t/yr from X. sorbifolia, 8.86× 106t/yr from C. humilis, 7.18 ×106t/yr from J. curcas, 9.55 × 106t/yr from P. chinensis, and 7.78 ×106 t/yr from C. wilsoniana.展开更多
文摘In Japan, floods occur frequently in urban areas because non-infiltrating areas are seeing increased urbanization. To prevent floods, urban basins must improve the infiltration capacity and water retention of the whole basin. There are several basic technologies for river basin management, such as infiltration trenches or rainwater storage. However, a method of soil amendment that prevents flood disasters has not been established. This study aims to evaluate the infiltration capacity of soil amendments using bamboo charcoal and humus. A constant-head infiltration test and rainfall simulation were conducted to evaluate the properties of the soil amendments. The constant-head infiltration test＇s results showed that soils mixed with 30% humus had the greatest potential for influencing initial and final infiltration rates, and the more the mixing rates of bamboo charcoal and humus were increased, the higher the water retention capacity. The results of the rainfall simulation showed that soils mixed with 30% humus had the highest final infiltration rates and lowest multiplication spillage. To reduce the runoff volume using soil amendment technology, it is important to delay overland flow, and the hydraulic properties of the soils mixed with bamboo charcoal and humus were as effective as those of granite soils.
文摘According to the Researches on Coal Development Strategies in China (1991 ~ 2020),the production scale of coal in China will increase to 2100 Mt in the year 2020 and the district layout of coal development and production will be diverted from the east to the central-west step by step. In addit1on, the multi-ply runnning struc ture-mines of the nation,the local and the village and town combined with produc tion scales of the large, the middle,and the small-will be kept. However,the tech nique of mining will be improved greatly.
文摘An improved spherical, movable transfer skirt for autonomous submersibles has been devised. It was designed to permit the transfer of equipment and personnel from a submersible to the pressure chamber of an oil storage sea-bed structure. It also allowed mating at large vertical angles while the submersible remained horizontal. Seal failure modes and procedures for analyzing the sealing ability of the mating flange of the hull transfer skirt were thoroughly analyzed using conservative estimation methods. In the analysis, sea currents and mating angles were considered. Results showed that when considering the effects of currents, spherical radius and mating angle, their influence on seal ring failure should be considered first. The critical mating depth for a seal ring failure was larger than for either sliding or rotational failure modes. The critical mating depth can be used to determine the mating method of the submersible. The analytical procedures and results can be used as a reference for the design of spherical hull transfer skirts.
文摘The authors once made a preliminary research on population carrying capacity of the land in the Economic Area of Zhujiang Delta (EAZD for short) in 1995, and reckoned that the ultimate population in this region will be 23 550 thousand by year of 2000. While the population in being in EAZD was 22.62 million in 1999.This accords with the prefigured result in the rough from the point of view of development. According to the data of plow land resources from the 2000 Statistical Yearbook of EAZD and the study on the population-foodstuff-plow land relationship, this paper calculates the productive potential of plow land and the population carrying capacity of land by year of 2010, and puts forward the countermeasures for improving the population carrying capacity of land in this region.
文摘The paper presents the measurement campaign of wind energy potential undertaken in Republic of Macedonia on four sites from the middle of 2006. The wind data analysis has been performed for one site, following with the assessment of energy production of simulated wind park with six wind turbine generators.
文摘Generative resources are mainly derived from the students （sometimes from the teachers）, which is dynamically generated in the students＇ practice, self-inquiry, and cooperative communication. Gifted children refer to a group of children who have such characteristics as high IQ （intelligence quotient）, strong creativity, and good personality. Their intelligence and capability have great potential for further development. As cognitive ability is one of the prominent characteristics of supernormal children, the lecturers can not only pay attention to teaching knowledge （facts teaching）, but also need provide proper opportunities for them to develop their aggressiveness, creativities, and challenges when teaching these children. Because students are active in thinking, in the classroom, students often have some unexpected ideas, that is, the generation of the classroom, in the face of this situation, teachers should be how to do？ A joke between students in the class, sparked the interest of a classmate, and then under the teachers＇ guidance, they invented a chemistry experiment instrument Ω type pipe, illustrated the importance of the teachers focus on creating teaching.
基金Under the auspices of National Science and Technology Support Project of China(No.2013BAJ11B02)
文摘Energy crops are a basic material in the bioenergy industry, and they can also mitigate carbon emissions and have environ- mental benefits when planted on marginal lands. The aim of this study was to evaluate the potential productivity of energy crops on marginal lands in China. A mechanistic model, combined with energy crop and land use characteristics, and meteorological and soil parameters, was used to simulate the potential productivity of energy crops. There were three main results. 1） The total marginal land in China was determined to be 104.78 × 106 ha. The 400-mm precipitation boundary line, which is the dividing line between the semi-humid and semi-arid zones in China, also divided the marginal land into shrub land and sparse forest land in the southeast and bare land, bare rock land, and saline alkali land in the northeast. 2） The total area of the marginal land suitable for planting energy crops was determined to be 55.82 × 106 ha, with Xanthoceras sorbifolia and Cerasus humilis mainly grown in the northern China, Jatropha curcas and Comus wilsoniana mainly grown in the southwest and southeast, and Pistacia chinensis mainly grown in the central area, while also having a northeast-southwest zonal distribution. 3） Taking the highest yield in overlapping areas, the potential productivity of target energy crops was determined to be 32.63 × 106 t/yr. Without considering the overlapping areas, the potential productivity was 6.81× 106 t/yr from X. sorbifolia, 8.86× 106t/yr from C. humilis, 7.18 ×106t/yr from J. curcas, 9.55 × 106t/yr from P. chinensis, and 7.78 ×106 t/yr from C. wilsoniana.
