[Objective] This paper aims to empirically analyze the situation of fertilizer overuse in China, considering that fertilizer, important for China＇s crop production, has brought serious environmental pollution to Chin...[Objective] This paper aims to empirically analyze the situation of fertilizer overuse in China, considering that fertilizer, important for China＇s crop production, has brought serious environmental pollution to China due to over application. [Method] Based on field survey data in four provinces of China, the magnitude of fertilizer overuse at farm level was empirically analyzed with Cobb-Douglas Produc- tion Function Method and profit optimization theory in the research. [Result] The resuits show that by average, 110.5 kg of chemical fertilizer were applied per mu of land, and 46.9 kg fertilizer was overused, occupying 42.5%. [Conclusion] There is large potential to reduce the overused amount and it is of great importance to re- duce fertilizer overuse effectively, which needs further intensive study.展开更多
[Objective] In this study, the aim was to explore the annual dosage and allocation proportion of nitrogenous fertilizer for Zhoumai 22 in the condition of wheat-maize integration. [Method] The rules of growth and yiel...[Objective] In this study, the aim was to explore the annual dosage and allocation proportion of nitrogenous fertilizer for Zhoumai 22 in the condition of wheat-maize integration. [Method] The rules of growth and yield variation of Zhoumai 22 under different dosages of nitrogenous fertilizer and different distribution ratios were studied. [Result] With the increase of nitrogenous fertilizer application and distribution rate from maize to wheat, the physiological indexes of Zhoumai 22 population showed an increasing trend, while the yield presented the variation trend of increasing firstly and decreasing then. [Conclusion] Annual amount of nitrogenous fertilizer of 600 kg/hm2 and the distribution ratio of 5：5 in the condition of wheat- maize integration was beneficial to the high yield of the whole year＇s crops and Zhoumai 22.展开更多
Bio-fuel can be used to help transition from a petroleum-based society to a bio-based society. Ever since the China Development and Reform Commission suspended the approval of crop processing programs, second-generati...Bio-fuel can be used to help transition from a petroleum-based society to a bio-based society. Ever since the China Development and Reform Commission suspended the approval of crop processing programs, second-generation bio-ethanol research and industrialization processes have attracted significant attention. In 2020, bio-ethanol production is predicted to reach 10 million tons. Currently, there are a few domestic enterprises that have established different scaled pilot or demonstration bases for cellulosic ethanol, which reduce the cost of ethanol by continuously improving pretreatment and hydrolysis techniques. In the next three years, these enterprises will realize large-scale commercial production. Given the practical problems in cellulosic ethanol plant construction and operation(e.g., marketing price variation and difficulties in feedstock collection), this paper began with the concept of a "whole-crop refinery" and presented a solution to the integration of industry and agriculture as well as multi-crop refining. This paper then took the whole-crop refining system of corn as an example and presented an analysis of the logistics, energy flow, and economical efficiency of the system. The results demonstrated that the integrated system could properly reduce the required fixed investments in production equipment,shared utilities, and wastewater treatment facilities, as well as reduction of energy consumption. Although the proposed system has several problems, it brings the long-term goal of large-scale commercial application closer than ever.展开更多
We describe a fiber optic hydrophone array system that could be used for underwater acoustic surveillance applications （e.g. military, counter terrorist, and customs authorities in protecting ports and harbors）, off...We describe a fiber optic hydrophone array system that could be used for underwater acoustic surveillance applications （e.g. military, counter terrorist, and customs authorities in protecting ports and harbors）, offshore production facilities or coastal approaches as well as various marine applications. In this paper, we propose a new approach to underwater sonar systems using the voltage-controlled liquid crystals and simple multiplexing method. The proposed method permits measurement of sound under water at multiple points along an optical fiber using the low cost components and standard single mode fiber, without complex interferometric measurement techniques, electronics or demodulation software.展开更多
文摘[Objective] This paper aims to empirically analyze the situation of fertilizer overuse in China, considering that fertilizer, important for China＇s crop production, has brought serious environmental pollution to China due to over application. [Method] Based on field survey data in four provinces of China, the magnitude of fertilizer overuse at farm level was empirically analyzed with Cobb-Douglas Produc- tion Function Method and profit optimization theory in the research. [Result] The resuits show that by average, 110.5 kg of chemical fertilizer were applied per mu of land, and 46.9 kg fertilizer was overused, occupying 42.5%. [Conclusion] There is large potential to reduce the overused amount and it is of great importance to re- duce fertilizer overuse effectively, which needs further intensive study.
基金Supported by the Project of National Wheat Industry Technology System in the"Twelfth Five-Year Plan"(CARS-3-2-34)~~
文摘[Objective] In this study, the aim was to explore the annual dosage and allocation proportion of nitrogenous fertilizer for Zhoumai 22 in the condition of wheat-maize integration. [Method] The rules of growth and yield variation of Zhoumai 22 under different dosages of nitrogenous fertilizer and different distribution ratios were studied. [Result] With the increase of nitrogenous fertilizer application and distribution rate from maize to wheat, the physiological indexes of Zhoumai 22 population showed an increasing trend, while the yield presented the variation trend of increasing firstly and decreasing then. [Conclusion] Annual amount of nitrogenous fertilizer of 600 kg/hm2 and the distribution ratio of 5：5 in the condition of wheat- maize integration was beneficial to the high yield of the whole year＇s crops and Zhoumai 22.
基金Supported by the State Key Development Program for Basic Research of China(2006BAC02A17)
文摘Bio-fuel can be used to help transition from a petroleum-based society to a bio-based society. Ever since the China Development and Reform Commission suspended the approval of crop processing programs, second-generation bio-ethanol research and industrialization processes have attracted significant attention. In 2020, bio-ethanol production is predicted to reach 10 million tons. Currently, there are a few domestic enterprises that have established different scaled pilot or demonstration bases for cellulosic ethanol, which reduce the cost of ethanol by continuously improving pretreatment and hydrolysis techniques. In the next three years, these enterprises will realize large-scale commercial production. Given the practical problems in cellulosic ethanol plant construction and operation(e.g., marketing price variation and difficulties in feedstock collection), this paper began with the concept of a "whole-crop refinery" and presented a solution to the integration of industry and agriculture as well as multi-crop refining. This paper then took the whole-crop refining system of corn as an example and presented an analysis of the logistics, energy flow, and economical efficiency of the system. The results demonstrated that the integrated system could properly reduce the required fixed investments in production equipment,shared utilities, and wastewater treatment facilities, as well as reduction of energy consumption. Although the proposed system has several problems, it brings the long-term goal of large-scale commercial application closer than ever.
文摘We describe a fiber optic hydrophone array system that could be used for underwater acoustic surveillance applications （e.g. military, counter terrorist, and customs authorities in protecting ports and harbors）, offshore production facilities or coastal approaches as well as various marine applications. In this paper, we propose a new approach to underwater sonar systems using the voltage-controlled liquid crystals and simple multiplexing method. The proposed method permits measurement of sound under water at multiple points along an optical fiber using the low cost components and standard single mode fiber, without complex interferometric measurement techniques, electronics or demodulation software.
