The impacts of climate change on China's agriculture are measured based on Ricardian model. By using county-level cross-sectional data on agricultural net revenue, climate, and other economic and geographical data...The impacts of climate change on China's agriculture are measured based on Ricardian model. By using county-level cross-sectional data on agricultural net revenue, climate, and other economic and geographical data for 1275 agriculture-dominated counties in the period of 1985-1991, we find that both higher temperature and more precipitation will have overall positive impact on China's agriculture. However, the impacts vary seasonally and regionally. Higher temperature in all seasons except spring increases agricultural net revenue while more precipitation is beneficial in winter but is harmful in summer. Applying the model to five climate scenarios in the 2020s and 2050s shows that the North, the Northeast, the Northwest, and the Qinghai-Tibet Plateau would always benefit from climate change while the South and the Southwest may be negatively affected. For the East and the Central China, most scenarios show that they may benefit from climate change. In conclusion, climate change would be beneficial to the whole China.展开更多
The development of eco-agricultural sightseeing in Baise City shows a sound foundation and outstanding advantages as well as a rapid growth trend in recent years, however, there are also problems to be settled, such a...The development of eco-agricultural sightseeing in Baise City shows a sound foundation and outstanding advantages as well as a rapid growth trend in recent years, however, there are also problems to be settled, such as shortage of talents, insufficient planning, low level of development, limited products and lack of competitive products. In view of such a condition, development concepts should be reformed first, competitive and special products made, marketing and propaganda enhanced to promote the healthy, coordinated and ordered development of eco-agricultural sightseeing in Baise City, Guangxi Zhuang Nationality Autonomous Region.展开更多
This article presents a study on the resistance to chloride penetration, corrosion, porosity, and strength of mortar containing fine fly ash (FA), ground rice husk-bark ash (RB), and ground bagasse ash (BA). Ord...This article presents a study on the resistance to chloride penetration, corrosion, porosity, and strength of mortar containing fine fly ash (FA), ground rice husk-bark ash (RB), and ground bagasse ash (BA). Ordinary Portland cement (CT) was blended with a single pozzolan and two pozzolans. Strength, porosity, rapid chloride penetration, immersion, and corrosion tests were performed to characterize the mortar. Test results showed that the use of ternary blends of CT, FA, and RB or BA decreased the porosity of the mortar, as compared with binary blended mortar containing CT and RB or BA. The resistance to chloride penetration of the mortar improved substantially with partial replacement of CT with FA, RB, and BA. The use of ternary blends of CT, FA and RB or BA produced the mortar with good strength and resistance to chloride penetration. The resistance to chloride penetration was higher with an increase in the replacement level due to the reduced calcium hydroxide.展开更多
The cost of cement has made concrete production expensive such that the housing deficit in developing countries is on the rise despite all the efforts by governments and other stakeholders to produce affordable housin...The cost of cement has made concrete production expensive such that the housing deficit in developing countries is on the rise despite all the efforts by governments and other stakeholders to produce affordable housing units for the populace. Ashes of agricultural products such as rice husk, known as mineral admixtures may have pozzolanic characteristics which would be more beneficial to the housing industry in terms of strength gain and economy than being pollutants to the environment. Rice Husk Ash (RHA), because of its finely divided form and very high silica content and amorphousness, proved to be useful for strength gain of Rice Husk Ash Concrete (RHAC). Rice husk ash was manufactured by uncontrolled burning, ground, sieved and replaced with cement at 0%, 5%, 10%, 15%, 20% and 25% in mass for the mixes C20, C25, C30 and C35 where their compressive strengths were verified at 3, 7, 14, 21, 28, 56, 90 and 180 days. The X-ray diffraction pattern list indicated amorphous as well as diffused peak of about 8000 counts of SiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> representing crystalline structures identified as cristobalite. A physical examination of the RHA showed very fine appearance, grey color and specific gravity of 2.06. The chemical analysis also revealed the existence of oxide content to be 55.8% representing 0.78% of Fe</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">, 54% of SiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and 1.06% of Al</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> representing 20.23% lower than the minimum value of 70% required for pozzolans. Generally, the compressive strength values decreased as the RHA content in the mixes increased but when compared to the control concrete the optimum replacement percentage of Ordinary Portland Cement (OPC) with RHA at 5% showed an increase above the control concrete for C20 mix. The increase in the RHA in the mixes resulted in the high demand for water in all the mixes.展开更多
China agriculture development, to some extent, is a reflection of China social development. Nowadays, China has goneglobal in industry, agriculture, technology, culture and education. However, China's agriculture ...China agriculture development, to some extent, is a reflection of China social development. Nowadays, China has goneglobal in industry, agriculture, technology, culture and education. However, China's agriculture development process is long per-ceived as a legend to outside world for unbelievable facts created after China launched its opening-up policy in 1978 and theHousehold Contract Responsibility System(HCRS) was formally established nationwide in 1981.展开更多
以Web of science、ESI和Incites三大数据源,采用文献计量学方法,从文献数量、质量角度,对国内18所农业院校2008-2018年的科研论文数量、被引频次、高被引论文、ESI学科、ESI潜势学科及区域合作开展分析,客观评价18所农业院校的科研水...以Web of science、ESI和Incites三大数据源,采用文献计量学方法,从文献数量、质量角度,对国内18所农业院校2008-2018年的科研论文数量、被引频次、高被引论文、ESI学科、ESI潜势学科及区域合作开展分析,客观评价18所农业院校的科研水平与科研实力,为提高农业院校的科研竞争力提供参考。展开更多
基金Young Scientist Summer Program at the International Institute for Applied System Analysis, YSSP 1999, Austria
文摘The impacts of climate change on China's agriculture are measured based on Ricardian model. By using county-level cross-sectional data on agricultural net revenue, climate, and other economic and geographical data for 1275 agriculture-dominated counties in the period of 1985-1991, we find that both higher temperature and more precipitation will have overall positive impact on China's agriculture. However, the impacts vary seasonally and regionally. Higher temperature in all seasons except spring increases agricultural net revenue while more precipitation is beneficial in winter but is harmful in summer. Applying the model to five climate scenarios in the 2020s and 2050s shows that the North, the Northeast, the Northwest, and the Qinghai-Tibet Plateau would always benefit from climate change while the South and the Southwest may be negatively affected. For the East and the Central China, most scenarios show that they may benefit from climate change. In conclusion, climate change would be beneficial to the whole China.
基金Sponsored by Key Program of Baise University(2009KA04)~~
文摘The development of eco-agricultural sightseeing in Baise City shows a sound foundation and outstanding advantages as well as a rapid growth trend in recent years, however, there are also problems to be settled, such as shortage of talents, insufficient planning, low level of development, limited products and lack of competitive products. In view of such a condition, development concepts should be reformed first, competitive and special products made, marketing and propaganda enhanced to promote the healthy, coordinated and ordered development of eco-agricultural sightseeing in Baise City, Guangxi Zhuang Nationality Autonomous Region.
基金financially supported by the Office of the National Research Council of Thailand (NRCT)Higher Education Research Promotion and National Research University Project of Thailand+2 种基金Office of the Higher Education Commission,through the Advanced Functional Materials Cluster of Khon Kaen Universitythe Thailand Research Fund (TRF) under the TRF Senior Research Scholar Contract No. RTA5480004Rajamangala University of Technology Phra Nakhon (RMUTP)
文摘This article presents a study on the resistance to chloride penetration, corrosion, porosity, and strength of mortar containing fine fly ash (FA), ground rice husk-bark ash (RB), and ground bagasse ash (BA). Ordinary Portland cement (CT) was blended with a single pozzolan and two pozzolans. Strength, porosity, rapid chloride penetration, immersion, and corrosion tests were performed to characterize the mortar. Test results showed that the use of ternary blends of CT, FA, and RB or BA decreased the porosity of the mortar, as compared with binary blended mortar containing CT and RB or BA. The resistance to chloride penetration of the mortar improved substantially with partial replacement of CT with FA, RB, and BA. The use of ternary blends of CT, FA and RB or BA produced the mortar with good strength and resistance to chloride penetration. The resistance to chloride penetration was higher with an increase in the replacement level due to the reduced calcium hydroxide.
文摘The cost of cement has made concrete production expensive such that the housing deficit in developing countries is on the rise despite all the efforts by governments and other stakeholders to produce affordable housing units for the populace. Ashes of agricultural products such as rice husk, known as mineral admixtures may have pozzolanic characteristics which would be more beneficial to the housing industry in terms of strength gain and economy than being pollutants to the environment. Rice Husk Ash (RHA), because of its finely divided form and very high silica content and amorphousness, proved to be useful for strength gain of Rice Husk Ash Concrete (RHAC). Rice husk ash was manufactured by uncontrolled burning, ground, sieved and replaced with cement at 0%, 5%, 10%, 15%, 20% and 25% in mass for the mixes C20, C25, C30 and C35 where their compressive strengths were verified at 3, 7, 14, 21, 28, 56, 90 and 180 days. The X-ray diffraction pattern list indicated amorphous as well as diffused peak of about 8000 counts of SiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> representing crystalline structures identified as cristobalite. A physical examination of the RHA showed very fine appearance, grey color and specific gravity of 2.06. The chemical analysis also revealed the existence of oxide content to be 55.8% representing 0.78% of Fe</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">, 54% of SiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and 1.06% of Al</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> representing 20.23% lower than the minimum value of 70% required for pozzolans. Generally, the compressive strength values decreased as the RHA content in the mixes increased but when compared to the control concrete the optimum replacement percentage of Ordinary Portland Cement (OPC) with RHA at 5% showed an increase above the control concrete for C20 mix. The increase in the RHA in the mixes resulted in the high demand for water in all the mixes.
文摘China agriculture development, to some extent, is a reflection of China social development. Nowadays, China has goneglobal in industry, agriculture, technology, culture and education. However, China's agriculture development process is long per-ceived as a legend to outside world for unbelievable facts created after China launched its opening-up policy in 1978 and theHousehold Contract Responsibility System(HCRS) was formally established nationwide in 1981.
文摘以Web of science、ESI和Incites三大数据源,采用文献计量学方法,从文献数量、质量角度,对国内18所农业院校2008-2018年的科研论文数量、被引频次、高被引论文、ESI学科、ESI潜势学科及区域合作开展分析,客观评价18所农业院校的科研水平与科研实力,为提高农业院校的科研竞争力提供参考。