[Objective] The aim was to introduce the development and application of 2BDQ-8 rice direct sowing machine and provide a theoretical basis for rice mechanization production. [Method] 2BDQ-8 rice direct sowing machine w...[Objective] The aim was to introduce the development and application of 2BDQ-8 rice direct sowing machine and provide a theoretical basis for rice mechanization production. [Method] 2BDQ-8 rice direct sowing machine was used for the promotion test in field of several cities and counties in Jiangsu Province,and artificial rice planting and mechanization rice planting were compared to explore the production and economic situation. [Result] 2BDQ-8 rice direct sowing machine had advantages such as high efficiency and low cost,the rice direct sowing machine saved about 30% compared to the artificial rice planting and mechanization rice planting,and the overall efficiency was significant. [Conclusion] 2BDQ-8 rice sowing machine was a production technology that had low cost and high efficiency,which should be widely applied.展开更多
Coalbed methane(CBM) commercial development requires choosing the arrangement of the wells.This should be done by considering the corresponding input-output(investment-profit) efficiencies.Simulations were obtained fr...Coalbed methane(CBM) commercial development requires choosing the arrangement of the wells.This should be done by considering the corresponding input-output(investment-profit) efficiencies.Simulations were obtained from the computer modeling group(CMG) given the reservoir conditions of the Panzhuang block in the southern part of the Qinshui Basin.This is a demonstration region for CBM development located in Shanxi province of northern China.The sensitivity of gas production from a single vertical well to the primary reservoir parameters was estimated first.Then multi-well gas production from three different well patterns was simulated to estimate the most appropriate well spacing.Combining the investment requirements then gave investment-profit efficiencies for these well patterns.A data envelopment analysis(DEA) model was used to optimize the efficiency.The results show that the permeability,the reservoir pressure,and the gas content have an evident impact on single well gas production.The desorption time has little or no affect on production.The equilateral triangular well pattern(ETWP) in a 400 m well spacing is,for multi-well development,the optimal pattern.It has a better input-output ratio,a longer stable yield time,and provides for greater CBM recovery than does either the rectangular well pattern(RWP) or the five point well pattern(FPWP).展开更多
In order to quantify the virtual water part which is contained in the imported cereals, compared with the hydraulic potentialities which are annually mobilised through the national territory, and on the basis of the a...In order to quantify the virtual water part which is contained in the imported cereals, compared with the hydraulic potentialities which are annually mobilised through the national territory, and on the basis of the agricultural statistics, we have determined the average quantities of the imported cereals per year in order to determine the virtual water volume that these cereals bind. The water needs of the cereals which are produced in Algeria have been calculated by the Cropwat software, in order to define the equivalent quantities of water in their production on the national scale. The obtained results confirm the importance of the annually imported virtual water, through the imported cereals, comparing with the national hydraulic potentialities. Our study shows also that in spite of the strategic importance of the virtual water in the imported cereals, a diminution has to take place, on the average term, by an improvement of the use efficiency of the precipitations (green virtual water) using the best mastery of the technical itinerary in general, and also the efficient use of precipitations in particular.展开更多
Food waste has developed as an alternative for the production of renewable fuels such as biogas from AD (anaerobic digestion). In relation to the biogas production rate, digester temperature setting is one of the ve...Food waste has developed as an alternative for the production of renewable fuels such as biogas from AD (anaerobic digestion). In relation to the biogas production rate, digester temperature setting is one of the very important factors for digester operation, especially in low temperature countries. In this study, the effect of digester temperature on biogas and methane production efficiency in the AD of food waste was evaluated. The two-stage anaerobic digestion has a total reactor volume of 60 L (acid reactor volume was 30 L and methane reactor volume was 30 L). They were incubated at mesophilic and thermophilic conditions for 25 days to determine temperature profiles for the AD process. The results of the laboratory-scale experiment show that maximum biogas production occurred at 55 ℃ (38.14 L of biogas) for a period of 11 days when compared to other temperatures. Second best was at 50 ℃ (37.44 L of biogas) for a period of 12 days, followed by 40 ℃ (35.36 L of biogas) for a period of 15 days. Thermophilic temperatures will be used in further studies to examine scaling up of the process.展开更多
Today's production systems are demanded to exhibit an increased flexibility and mutability in order to deal with dynamically changing conditions, objectives and an increasing number of product variants within industr...Today's production systems are demanded to exhibit an increased flexibility and mutability in order to deal with dynamically changing conditions, objectives and an increasing number of product variants within industrial turbulent environments. Flexible automated systems are requested in order to improve dynamic production efficiency, e.g. robot-based hardware and PC-based controllers, but these usually induce a significantly higher production complexity, whereby the efforts for planning and programming, but also setups and reconfiguration, expand. In this paper a definition and some concepts of self-optimizing assembly systems are presented to describe possible ways to reduce the planning efforts in complex production systems. The concept of self-optimization in assembly systems will be derived from a theoretical approach and will be transferred to a specific application scenario---the automated assembly of a miniaturized solid state laser--where the challenges of unpredictable influences from e.g. component tolerances can be overcome by the help of self-optimization.展开更多
The improvement of propionic acid production for antifungal activity, as fermenting by calcium alginate immobilized cells of Propionibacterium acidipropionici TISTR 442 was investigated by using whey as substrate. Opt...The improvement of propionic acid production for antifungal activity, as fermenting by calcium alginate immobilized cells of Propionibacterium acidipropionici TISTR 442 was investigated by using whey as substrate. Optimal condition for immobilization was performed by adjusting tube distance to CaCI2 solution to be 4-6 cm and 7 mL/min flow rate of alginate gel. The production of propionic acid by immobilized cells in a 2 L fermentor using 1% CaCO3 and 5 N KOH to control the pH at 6.5 gave maximum propionic acid and they had consistent potential to recycle 2 rounds of fermentation and produced the total of 29.24 g/L propionic acid (15.85 ± 0.25 g/L and 13.39 ± 0.25 g/L propionic acid from Batch 1 and Batch 2 fermentation, respectively). Compared to free-cell fermentation, propionic acid productivity increased 20% (0.083 g/h vs. 0.070 g/h) and fermentation time reduced 11% (192 h vs. 216 h) in 2 L fermentor with 40 g/L initial total sugar from whey. The fermented propionic acid as well as the commercial propionic acid from chemical process was able to inhibit the growth of the fungal tested.展开更多
In Mediterranean countries forage crops and temporary grasslands are the most important supply even if severe moisture stress is common. In Italy, forage systems are various and differently located from North to South...In Mediterranean countries forage crops and temporary grasslands are the most important supply even if severe moisture stress is common. In Italy, forage systems are various and differently located from North to South of the mainland due to strong influence by rainfall distribution. Grasses and grazing cover 3.4 million ha of Italian utilized agricultural area (UAA) while alternated grassland and grass meadows cover 1.9 million ha. Most of grasslands are located in hilly and mountainous areas and are important for reducing erosion. Italy has a great longitudinal extension which accounts for a great variety of climate systems and soils: the northern regions have a humid subtropical climate and differ greatly from the south part that fits the Mediterranean climate profile. During the last 100/150 years the Italian climate has become warmer and drier showing an increase of erratic precipitation intensity. The future of breeding of forage grasses and legumes should be focused on higher nutrient use efficiencies and increased sustainability. New applications of genomics and bioinformatics will allow advanced breeding strategies. Over the past 15 years breeders have displayed a constant interest in forage species while a greater interest has risen in turfgrass varieties. Seed production of Italian herbages does not cover the requirements of the market. More specific value for cultivation and use (VCU) tests might be an effective means to improve the screening of candidate varieties. The goal is the selection of varieties able to withstand the stress of climate change, have better water and nitrogen use efficiency and resilience of vegetation cover.展开更多
Our analysis of the surface aerosol and ultraviolet (UV) measurements in Pearl River Delta (PRD) region shows that the surface UV radiation is reduced by more than 50% due to high aerosol concentrations. This has ...Our analysis of the surface aerosol and ultraviolet (UV) measurements in Pearl River Delta (PRD) region shows that the surface UV radiation is reduced by more than 50% due to high aerosol concentrations. This has important impacts on urban ecosystem and photochemistry, especially on ozone photochemical production over the region. The quantitative effect of aerosols on surface ozone is evaluated by analyzing surface observations (including ozone, ultraviolet radiation, aerosol radiative parameters) and by using radiative and chemical models. A case study shows that the aerosol concentrations and UV radiation are significantly correlated with ozone concentrations. The correlation coefficient between the aerosol optical depth (AOD) and the PM10 mass concentration is very high, with a maximum of 0.98, and the AOD and UV radiation/ozone is anti- correlated, with a correlation coefficient of-0.90. The analysis suggests that ozone productivity is significantly decreased due to the reduction of UV radiation. The noon-time ozone maximum is considerably depressed when AOD is 0.6, and is further decreased when AOD is up to 1.2 due to the reduction of ozone photochemical productivity. Because the occurring probability of aerosol optical depth for AOD550m≥0.6 and AOD340mm ≥1.0 is 47, and 55% respectively during the dry season (October, November, December, January), this heavy aerosol condition explains the low ozone maximum that often occurs in the dry season over the Guangzhou region. The analysis also suggests that the value of single scattering albedo (SSA) is very sensitive to the aerosol radiative effect when the radiative and chemical models are applied, implying that the value of SSA needs to be carefully studied when the models are used in calculating ozone production.展开更多
When the high-income East Asian economies entered the upper-middle income stage,their long-term growth was sustained by their real manufacturing output share and total factor productivity(TFP).This is a typical patter...When the high-income East Asian economies entered the upper-middle income stage,their long-term growth was sustained by their real manufacturing output share and total factor productivity(TFP).This is a typical pattern that is highly consistent with classical development economics,which sees manufacturing as the engine of economic growth.When China became a middle-income country,its share of real manufacturing output and TFP both fell over the same period,exhibiting a theoretical and empirical tendency toward“premature deindustrialization”that increases the risk of being caught in the middle-income trap.Accelerating China’s development as a manufacturing power,advancing high-tech manufacturing and improving the quality and efficiency of traditional industries are realistic options for the country’s industrial development strategy.展开更多
基金Supported by the Subprogram " the Mechanization Development of High Speed Rice Sowing-Rice Direct Sowing Machine" of the Programs of Science Research for the "10th Five-year Plan" of MinistryScience and Technology (2001BA504B01-02)~~
文摘[Objective] The aim was to introduce the development and application of 2BDQ-8 rice direct sowing machine and provide a theoretical basis for rice mechanization production. [Method] 2BDQ-8 rice direct sowing machine was used for the promotion test in field of several cities and counties in Jiangsu Province,and artificial rice planting and mechanization rice planting were compared to explore the production and economic situation. [Result] 2BDQ-8 rice direct sowing machine had advantages such as high efficiency and low cost,the rice direct sowing machine saved about 30% compared to the artificial rice planting and mechanization rice planting,and the overall efficiency was significant. [Conclusion] 2BDQ-8 rice sowing machine was a production technology that had low cost and high efficiency,which should be widely applied.
基金supported by the National Natural Science Foundation of China (No. 40972207)the National Science and Technology Major Projects (No. 2011ZX05034-005)the PAPD of Jiangsu Higher Education Institutions
文摘Coalbed methane(CBM) commercial development requires choosing the arrangement of the wells.This should be done by considering the corresponding input-output(investment-profit) efficiencies.Simulations were obtained from the computer modeling group(CMG) given the reservoir conditions of the Panzhuang block in the southern part of the Qinshui Basin.This is a demonstration region for CBM development located in Shanxi province of northern China.The sensitivity of gas production from a single vertical well to the primary reservoir parameters was estimated first.Then multi-well gas production from three different well patterns was simulated to estimate the most appropriate well spacing.Combining the investment requirements then gave investment-profit efficiencies for these well patterns.A data envelopment analysis(DEA) model was used to optimize the efficiency.The results show that the permeability,the reservoir pressure,and the gas content have an evident impact on single well gas production.The desorption time has little or no affect on production.The equilateral triangular well pattern(ETWP) in a 400 m well spacing is,for multi-well development,the optimal pattern.It has a better input-output ratio,a longer stable yield time,and provides for greater CBM recovery than does either the rectangular well pattern(RWP) or the five point well pattern(FPWP).
文摘In order to quantify the virtual water part which is contained in the imported cereals, compared with the hydraulic potentialities which are annually mobilised through the national territory, and on the basis of the agricultural statistics, we have determined the average quantities of the imported cereals per year in order to determine the virtual water volume that these cereals bind. The water needs of the cereals which are produced in Algeria have been calculated by the Cropwat software, in order to define the equivalent quantities of water in their production on the national scale. The obtained results confirm the importance of the annually imported virtual water, through the imported cereals, comparing with the national hydraulic potentialities. Our study shows also that in spite of the strategic importance of the virtual water in the imported cereals, a diminution has to take place, on the average term, by an improvement of the use efficiency of the precipitations (green virtual water) using the best mastery of the technical itinerary in general, and also the efficient use of precipitations in particular.
文摘Food waste has developed as an alternative for the production of renewable fuels such as biogas from AD (anaerobic digestion). In relation to the biogas production rate, digester temperature setting is one of the very important factors for digester operation, especially in low temperature countries. In this study, the effect of digester temperature on biogas and methane production efficiency in the AD of food waste was evaluated. The two-stage anaerobic digestion has a total reactor volume of 60 L (acid reactor volume was 30 L and methane reactor volume was 30 L). They were incubated at mesophilic and thermophilic conditions for 25 days to determine temperature profiles for the AD process. The results of the laboratory-scale experiment show that maximum biogas production occurred at 55 ℃ (38.14 L of biogas) for a period of 11 days when compared to other temperatures. Second best was at 50 ℃ (37.44 L of biogas) for a period of 12 days, followed by 40 ℃ (35.36 L of biogas) for a period of 15 days. Thermophilic temperatures will be used in further studies to examine scaling up of the process.
文摘Today's production systems are demanded to exhibit an increased flexibility and mutability in order to deal with dynamically changing conditions, objectives and an increasing number of product variants within industrial turbulent environments. Flexible automated systems are requested in order to improve dynamic production efficiency, e.g. robot-based hardware and PC-based controllers, but these usually induce a significantly higher production complexity, whereby the efforts for planning and programming, but also setups and reconfiguration, expand. In this paper a definition and some concepts of self-optimizing assembly systems are presented to describe possible ways to reduce the planning efforts in complex production systems. The concept of self-optimization in assembly systems will be derived from a theoretical approach and will be transferred to a specific application scenario---the automated assembly of a miniaturized solid state laser--where the challenges of unpredictable influences from e.g. component tolerances can be overcome by the help of self-optimization.
文摘The improvement of propionic acid production for antifungal activity, as fermenting by calcium alginate immobilized cells of Propionibacterium acidipropionici TISTR 442 was investigated by using whey as substrate. Optimal condition for immobilization was performed by adjusting tube distance to CaCI2 solution to be 4-6 cm and 7 mL/min flow rate of alginate gel. The production of propionic acid by immobilized cells in a 2 L fermentor using 1% CaCO3 and 5 N KOH to control the pH at 6.5 gave maximum propionic acid and they had consistent potential to recycle 2 rounds of fermentation and produced the total of 29.24 g/L propionic acid (15.85 ± 0.25 g/L and 13.39 ± 0.25 g/L propionic acid from Batch 1 and Batch 2 fermentation, respectively). Compared to free-cell fermentation, propionic acid productivity increased 20% (0.083 g/h vs. 0.070 g/h) and fermentation time reduced 11% (192 h vs. 216 h) in 2 L fermentor with 40 g/L initial total sugar from whey. The fermented propionic acid as well as the commercial propionic acid from chemical process was able to inhibit the growth of the fungal tested.
文摘In Mediterranean countries forage crops and temporary grasslands are the most important supply even if severe moisture stress is common. In Italy, forage systems are various and differently located from North to South of the mainland due to strong influence by rainfall distribution. Grasses and grazing cover 3.4 million ha of Italian utilized agricultural area (UAA) while alternated grassland and grass meadows cover 1.9 million ha. Most of grasslands are located in hilly and mountainous areas and are important for reducing erosion. Italy has a great longitudinal extension which accounts for a great variety of climate systems and soils: the northern regions have a humid subtropical climate and differ greatly from the south part that fits the Mediterranean climate profile. During the last 100/150 years the Italian climate has become warmer and drier showing an increase of erratic precipitation intensity. The future of breeding of forage grasses and legumes should be focused on higher nutrient use efficiencies and increased sustainability. New applications of genomics and bioinformatics will allow advanced breeding strategies. Over the past 15 years breeders have displayed a constant interest in forage species while a greater interest has risen in turfgrass varieties. Seed production of Italian herbages does not cover the requirements of the market. More specific value for cultivation and use (VCU) tests might be an effective means to improve the screening of candidate varieties. The goal is the selection of varieties able to withstand the stress of climate change, have better water and nitrogen use efficiency and resilience of vegetation cover.
基金supported by National Natural Science Foundation of China (Grant Nos. 40875090, 40375002, 40775011)Natural Science Foundation of Guangdong Province (Grant No. 7035008)Tropical Marine Meteorological Science Foundation (Grant No. 200502)
文摘Our analysis of the surface aerosol and ultraviolet (UV) measurements in Pearl River Delta (PRD) region shows that the surface UV radiation is reduced by more than 50% due to high aerosol concentrations. This has important impacts on urban ecosystem and photochemistry, especially on ozone photochemical production over the region. The quantitative effect of aerosols on surface ozone is evaluated by analyzing surface observations (including ozone, ultraviolet radiation, aerosol radiative parameters) and by using radiative and chemical models. A case study shows that the aerosol concentrations and UV radiation are significantly correlated with ozone concentrations. The correlation coefficient between the aerosol optical depth (AOD) and the PM10 mass concentration is very high, with a maximum of 0.98, and the AOD and UV radiation/ozone is anti- correlated, with a correlation coefficient of-0.90. The analysis suggests that ozone productivity is significantly decreased due to the reduction of UV radiation. The noon-time ozone maximum is considerably depressed when AOD is 0.6, and is further decreased when AOD is up to 1.2 due to the reduction of ozone photochemical productivity. Because the occurring probability of aerosol optical depth for AOD550m≥0.6 and AOD340mm ≥1.0 is 47, and 55% respectively during the dry season (October, November, December, January), this heavy aerosol condition explains the low ozone maximum that often occurs in the dry season over the Guangzhou region. The analysis also suggests that the value of single scattering albedo (SSA) is very sensitive to the aerosol radiative effect when the radiative and chemical models are applied, implying that the value of SSA needs to be carefully studied when the models are used in calculating ozone production.
文摘When the high-income East Asian economies entered the upper-middle income stage,their long-term growth was sustained by their real manufacturing output share and total factor productivity(TFP).This is a typical pattern that is highly consistent with classical development economics,which sees manufacturing as the engine of economic growth.When China became a middle-income country,its share of real manufacturing output and TFP both fell over the same period,exhibiting a theoretical and empirical tendency toward“premature deindustrialization”that increases the risk of being caught in the middle-income trap.Accelerating China’s development as a manufacturing power,advancing high-tech manufacturing and improving the quality and efficiency of traditional industries are realistic options for the country’s industrial development strategy.