Background:This study was conducted to evaluate the feed nutritional value of brewers’spent grain(BSG)residue resulting from protease aided protein removal.The nutritional value was measured as nutrient content,gas p...Background:This study was conducted to evaluate the feed nutritional value of brewers’spent grain(BSG)residue resulting from protease aided protein removal.The nutritional value was measured as nutrient content,gas production,nutrient digestibility and fermentation characteristics in batch culture.Results:Protein extraction process decreased content of crude protein but concentrated the neutral detergent fibre(NDF)and ferulic acid in BSG residue.The changes in the chemical composition of BSG residue varied with enzyme and enzyme dosage.Digestibility of dry matter(DMD)and NDF of residue differed among proteases.Increasing alcalase dosage linearly decreased DMD,whereas,the DMD linearly increased as everlase or flavourzyme dosage increased.Compared with BSG,the DMD,gas production and fermentation acid concentration of BSG residues were lower,whereas NDF digestibility was higher.Conclusions:The substantially increased NDF content and improved in vitro NDF digestibility due to protease hydrolysis suggest that BSG residue can be potentially exploited as a viable fibre source for ruminant feeding.展开更多
Abstract: Daqu distiller's grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The singl...Abstract: Daqu distiller's grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The single factor tests were used to investigate the effects of ratio of strains, inoculum size, culture temperature and culture time on the production of microbial oils. The best processing conditions were obtained by orthogonal test through measuring the content of microbial oils in product. The result shows that the microbial oils content of the co-fermented product under the ratio of Trichoderma.koningii to Trichosporon cutaneum of 1:1, the inoculum size of strains of 11% at 28 ℃ for 6 d is 7.15 g/L. It is shown that the production of microbial oils co-fermented by Trichoderma.koningii and Trichosporon cutaneum with Daqu distiller's grains is possible. The research provides a new idea for the reuse of Daqu distiller's grains and also provides a new way for the development of microbial oils.展开更多
The properties of extracellular cellulase obtained from Bacillus species (FIIRO Strain B223) on supplying cellulose from Brewers Spent Grain (BSG) were studied. Generally, a crude cellulase activity between 11,757 Uni...The properties of extracellular cellulase obtained from Bacillus species (FIIRO Strain B223) on supplying cellulose from Brewers Spent Grain (BSG) were studied. Generally, a crude cellulase activity between 11,757 Units to 13,930 Units was observed for both sources of carbon (BSG and crystalline cellulose). The optimum pH and temperature of 5.0, and 30°C - 40°C for both sources of carbon was observed. Heavy metals such as copper, zinc, and iron inhibited the activities of B223 cellulase while the cellulase activities on alkaline earth metal (manganese) were moderate. The co-factor behaviour of manganese ion was also established. Local production of cellulase in Nigeria using local raw materials such as Brewers Spent Grain reduces enzyme cost;cost of finished products and increases gross domestic products.展开更多
Pot experiments were conducted to study the effects of different organic fertilizers made from distiller's grains on the physiological characteristics and growth of flue-cured tobacco. The results showed that the agr...Pot experiments were conducted to study the effects of different organic fertilizers made from distiller's grains on the physiological characteristics and growth of flue-cured tobacco. The results showed that the agronomic traits and biomass of flue-cured tobacco in the three treatments were higher than that of the control group,and the mixed application of different organic fertilizers made from distiller's grains and compound fertilizer could promote the growth and development of flue-cured tobacco significantly.展开更多
Purpose: To extract protein, decrease the cellulose and facilitate the digestion and absorption of brewers' spent grain by animal. Topic: Discuss and optimize the hydrolysis conditions of the combined enzymatic hyd...Purpose: To extract protein, decrease the cellulose and facilitate the digestion and absorption of brewers' spent grain by animal. Topic: Discuss and optimize the hydrolysis conditions of the combined enzymatic hydrolysis by Novozymes. Method: The fresh brewers' spent grain was firstly dried, smashed and sifted. Then as indicators of the protein extraction rate in the enzyme solution and the content of cellulose in the index, the parameters of enzymatic hydrolysis, such as the solid-liquid ratio, reaction temperature, pH, enzyme dosage and reaction time, were investigated in detailed. After hydrolysis, the brewers' spent grain was put in the boiling water bath for inactivation for 15 minutes, and centrifuged, the supernatants were volume to 100 mL and the protein content was measured. After the precipitate was dried, the cellulose content was also measured. Achievements: The optimized conditions were with temperature of 50 ℃, pH 6.5, enzyme amount of 30 mg for Novozymes enzyme and 2.5 h for reaction time. Under these conditions, the protein extraction rate in the enzyme reaction reached 41.82%, and the cellulose content reached 13.90%, the degradation rate of cellulose was 18.86%.展开更多
This paper analyzes a pro-forma economic market and supply chain system for the reuse of a lignocellulose (brewer’s spent grain) in an industrial biotechnology environment. An extant literature review was conducted, ...This paper analyzes a pro-forma economic market and supply chain system for the reuse of a lignocellulose (brewer’s spent grain) in an industrial biotechnology environment. An extant literature review was conducted, followed by a technical analysis of BSG, and the development of a supply chain system and economic market analysis based upon a participant brewing company and industry experts. In this paper, it was found that, even with the potential for future improvements in the conversion of brewer’s spent grain (BSG) from an efficiency standpoint, this industrial residual is supply chain prohibitive as a biofeedstock in comparison to other lignocellulose materials, therefore, centralized market relationships would not be advantageous for sellers and buyers. Future research should consider the viability of centralized supply chain structures for alternatives that may exist as future bio-feedstocks.展开更多
In China, the quantity of farmer's grain storage covers about 40% of the total grain yield every year. While, the losses of farms' grain storage are up to 8%, which is due to the lack of grain storage facility and t...In China, the quantity of farmer's grain storage covers about 40% of the total grain yield every year. While, the losses of farms' grain storage are up to 8%, which is due to the lack of grain storage facility and technology. The losses of farmer's grain storage could reach nearly 20 million tons every year. In this paper, the current situation and development of grain storage technology and facility for Chinese farmers were presented. And a series of policy and research work for reducing the losses of farms' grain storage was introduced. The large scale farmers are now developing quickly in China, the new storage warehouse and mechanized facility should be developed adaptively. So, the new storage technology and policy to meet the need of large scale farmers were also introduced in this paper.展开更多
In order to reduce the use of peat resources and realize the sustainable development of tobacco, the pH of distiller s grain substrate was adjusted with humic acid, and the effects of various distiller s grain substra...In order to reduce the use of peat resources and realize the sustainable development of tobacco, the pH of distiller s grain substrate was adjusted with humic acid, and the effects of various distiller s grain substrates on the growth of tobacco seedlings were studied to find out the method of cultivating high-quality tobacco seedlings by using distiller s grain substrate. The results showed that when 60% of humic acid was added to the distiller s grain substrate made from coarse distiller s grains, fine distiller s grains, perlite and vermiculite, both the pH and electrical conductivity decreased significantly and were similar to that of the conventional substrate. Moreover, the emergence rate of tobacco seedlings, the rate of strong tobacco seedlings, leaf number, stem height, root growth and quality of tobacco seedlings were good.展开更多
The effect of grain size of CaCO3 and SiO2 on the formation of C3S under various conditions, such as rapid heating rate(800 ℃/min), normal heating rate(30 ℃/min) and in the presence or absence of ZnO, was studie...The effect of grain size of CaCO3 and SiO2 on the formation of C3S under various conditions, such as rapid heating rate(800 ℃/min), normal heating rate(30 ℃/min) and in the presence or absence of ZnO, was studied. The results show that the decomposition temperature of CaCO3, the temperature of appearance of liquid phase and the f-CaO content descend when the grain size of CaCO3 and SiO2 becomes smaller, which attributes to the reactive activity enhancement of powders due to the decrease of the particle size. When the grain size of CaCO3 and SiO2 is below 1 μm, the rate of the formation of C3S is greatly raised. A rapid sintering rate and the presence of ZnO have an important effect on the formation of C3S and can lower the temperature of the formation of C3S by about 50 ℃.展开更多
In order to investigate the elastic properties of directionally solidified(DS)superalloys,an elasticity model called boundaries elastic model(GBE model),considering grain boundaries and tensile orientations,is propose...In order to investigate the elastic properties of directionally solidified(DS)superalloys,an elasticity model called boundaries elastic model(GBE model),considering grain boundaries and tensile orientations,is proposed in this paper.Two assumptions are adopted in the GBE model:(1)The displacement of grains,which moves along the perpendicular direction,is restricted by the grain boundaries;(2)Grain boundaries influence region(GBIR)is formed around the grain boundaries.Based on the single crystal(SC)calculation method of elastic properties,the GBE model can well predict macroscopic equivalent elastic modulus(Young’s modulus)of DS superalloys under different tensile orientations effectively.To demonstrate the correctness of the GBE model,3D finite element simulation is adopted and tensile experiments on a Ni3Al?base DS superalloy(IC10)along five tensile orientations are carried out.Meanwhile,the grain boundaries are observed by light microscopy and transmission electron microscope(TEM).Therefore,the GBE model is proved to be feasible by comparing the simulated results with the experiments.展开更多
Yeasts resulting from the brewing process (RBY) are a valuable by-product, with an important content of minerals, vitamins and, especially, proteins. The purpose of the research was the electroactivation of RBY and th...Yeasts resulting from the brewing process (RBY) are a valuable by-product, with an important content of minerals, vitamins and, especially, proteins. The purpose of the research was the electroactivation of RBY and the simultaneous obtaining of two products</span><span style="font-family:"">—<span>protein concentrates and hydrolyzed protein fr<span>om residual brewer’s yeast. Electroactivation is a non-residual process, wit</span>hout the use of chemical reagents and relatively inexpensive. The variation of the electroactivation conditions allowed the separation of 90% - 94% of the proteins in the form of protein concentrates. During the process, it is attested to increase the pH value and decrease the redox potential, which characterizes the multiple redox processes that take place in the cathode cell, including sedimentation at the isoelectric point. The presence of albumin in the protein fractions of RBY allows the formation of protein complexes with calcium, attributing a higher biological value to the obtained products.展开更多
为了降低电子传输层(Electron transport layer,ETL)与钙钛矿层之间的界面缺陷态密度,通过旋涂法在氧化铟锡(Indium tin oxide,ITO)透明导电玻璃上制备一层SnO_(2)电子传输层,并在其上表面旋涂(NH_(4))_(2)S以修饰SnO_(2)和钙钛矿光吸...为了降低电子传输层(Electron transport layer,ETL)与钙钛矿层之间的界面缺陷态密度,通过旋涂法在氧化铟锡(Indium tin oxide,ITO)透明导电玻璃上制备一层SnO_(2)电子传输层,并在其上表面旋涂(NH_(4))_(2)S以修饰SnO_(2)和钙钛矿光吸收层之间的界面。通过X射线光电子能谱、扫描电子显微镜、电化学阻抗谱等表征手段分析(NH_(4))_(2)S修饰对钙钛矿太阳能电池(Perovskite solar cells,PSCs)光电性能的影响。结果表明:NH_(4)^(+)降低了SnO_(2)的表面羟基(—OH)缺陷态密度,增强了界面的疏水性,减少了钙钛矿的形核位点,增大了钙钛矿晶粒;S^(2-)填补了SnO_(2)表面的氧空位(OV),同时部分S^(2-)还与未配位Pb^(2+)连接减少界面处Pb缺陷,抑制了界面处载流子复合;经过(NH_(4))_(2)S的修饰,PSCs开路电压从1.07 V提高到1.11 V,光电转化效率达到了20.53%。(NH_(4))2S修饰后的PSCs具有更高的光电转化效率、更好的长期稳定性。该研究可为PSCs商业化提供新的思路。展开更多
2008 is a year of bumper harvest in summer grain across China. The failure of numerous state-owned grain depots to purchase grain in times of bumper harvest, however, directly threatens grain reserve security and stat...2008 is a year of bumper harvest in summer grain across China. The failure of numerous state-owned grain depots to purchase grain in times of bumper harvest, however, directly threatens grain reserve security and state control over grain prices in the upcoming year. An important factor underpinning the difficulty of state grain depots to purchase grain is the unwillingness of farmers to sell grain due to the excess of the current market price over the government "protected price" aimed at preventing cheap grain from harming farmers. When grassroots grain depots find themselves in trouble, foreign capital stealthily moves in by taking advantage of this situation. To fulfill grain storage tasks and receive various state subsidies, some state-owned grain depots have no alternative but to surreptitiously raise the purchase price. By contrast, some not so courageous state-owned grain depots can only borrow money to finance the purchase of commodity grain at market prices and subsequently figure out a way to pay back such loans. Behind such distorted grain purchase behavior lies a rough and rugged history of grain price reform in China.展开更多
Agriculture is the foundation of the national economy,while grain is the cornet stone of that foundation.It is also essential for subsistence and development of the mankind. In recent years,especially since its entry ...Agriculture is the foundation of the national economy,while grain is the cornet stone of that foundation.It is also essential for subsistence and development of the mankind. In recent years,especially since its entry into the WTO, China has been undergoing a period of twists and turns in the development of its grain production and trade which used to be sound and stable.展开更多
Grain prices often dominate all other product prices,and an increase in their price is usually considered as a prelude to inflation.The three fairly serious inflations,in 1985,1988-1989,and 1993-1995 respectively,were...Grain prices often dominate all other product prices,and an increase in their price is usually considered as a prelude to inflation.The three fairly serious inflations,in 1985,1988-1989,and 1993-1995 respectively,were all preceded by grain price hikes.Furthermore,the money supply surged in the preceding year or during the same year in which these inflations occurred.This year has witnessed the same symptoms. High grain prices,which still have a possibility to go up further,have attracted wide attention across the world,including in China.As early as the end of last year,the State Council issued a circular that mandated the stabilization of grain prices in order to strictly crack down on illegal actions such as dishonest merchants driving up grain prices.One time,five State-level Departments led by National Development and Reform Commission,released an urgent announcement in order to safeguard the stability of grain prices in the domestic market.Wu Xiaoling,Vice Governor of the People's Bank of China,said that the negative influences exerted on other product prices by the rise in global grain price should not be ignored.According to Wu,the People's Bank of China will continue to closely watch the price changes. From a global and comprehensive viewpoint,the article analyzes the features of the recent grain price hike and the reasons for its dramatic rise,as well as,the impact it will have on the global economy.展开更多
This paper makes predictions for China’s grain production and its associated supply and demand situation up to 2030 by using input-occupancy-output techniques and systems science methodology. It argues that, taking i...This paper makes predictions for China’s grain production and its associated supply and demand situation up to 2030 by using input-occupancy-output techniques and systems science methodology. It argues that, taking into account its basic situation and world grain resources, China has no other choice but to count on self-sufficiency in terms of grain supply.展开更多
In China’s countryside today, so far the foodstuffs for daily-life subsistence are still taken from the traditional farming production in addition to the yield of animal husbandry, while crop plantation takes the lio...In China’s countryside today, so far the foodstuffs for daily-life subsistence are still taken from the traditional farming production in addition to the yield of animal husbandry, while crop plantation takes the lion’s share in our rural economy. During the Medieval Age of the Western countries, however, special stress was placed on raising livestock on pastureland until the Industrial Revolution occurred in the 18th century when grain-oriented agriculture came into being. As a result of the unprecedented boom of modern science and technology now sweeping the whole world, farming productivity has sky-展开更多
基金funded by AAFC Growing forward program(GF2#1542).
文摘Background:This study was conducted to evaluate the feed nutritional value of brewers’spent grain(BSG)residue resulting from protease aided protein removal.The nutritional value was measured as nutrient content,gas production,nutrient digestibility and fermentation characteristics in batch culture.Results:Protein extraction process decreased content of crude protein but concentrated the neutral detergent fibre(NDF)and ferulic acid in BSG residue.The changes in the chemical composition of BSG residue varied with enzyme and enzyme dosage.Digestibility of dry matter(DMD)and NDF of residue differed among proteases.Increasing alcalase dosage linearly decreased DMD,whereas,the DMD linearly increased as everlase or flavourzyme dosage increased.Compared with BSG,the DMD,gas production and fermentation acid concentration of BSG residues were lower,whereas NDF digestibility was higher.Conclusions:The substantially increased NDF content and improved in vitro NDF digestibility due to protease hydrolysis suggest that BSG residue can be potentially exploited as a viable fibre source for ruminant feeding.
基金Project(10A110) supported by Hunan Provincial Education Department of ChinaProject(2010JT4055) supported by Hunan Provincial Science & Technology Department of China
文摘Abstract: Daqu distiller's grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The single factor tests were used to investigate the effects of ratio of strains, inoculum size, culture temperature and culture time on the production of microbial oils. The best processing conditions were obtained by orthogonal test through measuring the content of microbial oils in product. The result shows that the microbial oils content of the co-fermented product under the ratio of Trichoderma.koningii to Trichosporon cutaneum of 1:1, the inoculum size of strains of 11% at 28 ℃ for 6 d is 7.15 g/L. It is shown that the production of microbial oils co-fermented by Trichoderma.koningii and Trichosporon cutaneum with Daqu distiller's grains is possible. The research provides a new idea for the reuse of Daqu distiller's grains and also provides a new way for the development of microbial oils.
文摘The properties of extracellular cellulase obtained from Bacillus species (FIIRO Strain B223) on supplying cellulose from Brewers Spent Grain (BSG) were studied. Generally, a crude cellulase activity between 11,757 Units to 13,930 Units was observed for both sources of carbon (BSG and crystalline cellulose). The optimum pH and temperature of 5.0, and 30°C - 40°C for both sources of carbon was observed. Heavy metals such as copper, zinc, and iron inhibited the activities of B223 cellulase while the cellulase activities on alkaline earth metal (manganese) were moderate. The co-factor behaviour of manganese ion was also established. Local production of cellulase in Nigeria using local raw materials such as Brewers Spent Grain reduces enzyme cost;cost of finished products and increases gross domestic products.
基金Supported by the Project of Luzhou Company of Sichuan Provincial Tobacco Company"Comprehensive Application of Distillers'Grains on Tobacco"
文摘Pot experiments were conducted to study the effects of different organic fertilizers made from distiller's grains on the physiological characteristics and growth of flue-cured tobacco. The results showed that the agronomic traits and biomass of flue-cured tobacco in the three treatments were higher than that of the control group,and the mixed application of different organic fertilizers made from distiller's grains and compound fertilizer could promote the growth and development of flue-cured tobacco significantly.
文摘Purpose: To extract protein, decrease the cellulose and facilitate the digestion and absorption of brewers' spent grain by animal. Topic: Discuss and optimize the hydrolysis conditions of the combined enzymatic hydrolysis by Novozymes. Method: The fresh brewers' spent grain was firstly dried, smashed and sifted. Then as indicators of the protein extraction rate in the enzyme solution and the content of cellulose in the index, the parameters of enzymatic hydrolysis, such as the solid-liquid ratio, reaction temperature, pH, enzyme dosage and reaction time, were investigated in detailed. After hydrolysis, the brewers' spent grain was put in the boiling water bath for inactivation for 15 minutes, and centrifuged, the supernatants were volume to 100 mL and the protein content was measured. After the precipitate was dried, the cellulose content was also measured. Achievements: The optimized conditions were with temperature of 50 ℃, pH 6.5, enzyme amount of 30 mg for Novozymes enzyme and 2.5 h for reaction time. Under these conditions, the protein extraction rate in the enzyme reaction reached 41.82%, and the cellulose content reached 13.90%, the degradation rate of cellulose was 18.86%.
文摘This paper analyzes a pro-forma economic market and supply chain system for the reuse of a lignocellulose (brewer’s spent grain) in an industrial biotechnology environment. An extant literature review was conducted, followed by a technical analysis of BSG, and the development of a supply chain system and economic market analysis based upon a participant brewing company and industry experts. In this paper, it was found that, even with the potential for future improvements in the conversion of brewer’s spent grain (BSG) from an efficiency standpoint, this industrial residual is supply chain prohibitive as a biofeedstock in comparison to other lignocellulose materials, therefore, centralized market relationships would not be advantageous for sellers and buyers. Future research should consider the viability of centralized supply chain structures for alternatives that may exist as future bio-feedstocks.
文摘In China, the quantity of farmer's grain storage covers about 40% of the total grain yield every year. While, the losses of farms' grain storage are up to 8%, which is due to the lack of grain storage facility and technology. The losses of farmer's grain storage could reach nearly 20 million tons every year. In this paper, the current situation and development of grain storage technology and facility for Chinese farmers were presented. And a series of policy and research work for reducing the losses of farms' grain storage was introduced. The large scale farmers are now developing quickly in China, the new storage warehouse and mechanized facility should be developed adaptively. So, the new storage technology and policy to meet the need of large scale farmers were also introduced in this paper.
基金Supported by the Project of Luzhou Company of Sichuan Provincial Tobacco Company"Comprehensive Application of Distillers'Grains on Tobacco"
文摘In order to reduce the use of peat resources and realize the sustainable development of tobacco, the pH of distiller s grain substrate was adjusted with humic acid, and the effects of various distiller s grain substrates on the growth of tobacco seedlings were studied to find out the method of cultivating high-quality tobacco seedlings by using distiller s grain substrate. The results showed that when 60% of humic acid was added to the distiller s grain substrate made from coarse distiller s grains, fine distiller s grains, perlite and vermiculite, both the pH and electrical conductivity decreased significantly and were similar to that of the conventional substrate. Moreover, the emergence rate of tobacco seedlings, the rate of strong tobacco seedlings, leaf number, stem height, root growth and quality of tobacco seedlings were good.
基金the Science Fund Project(No.04JY029-060-1)Key Subject Construction Project of Material Science of Sichuan Province of China and National Support Project(No.2006BAF02A24)
文摘The effect of grain size of CaCO3 and SiO2 on the formation of C3S under various conditions, such as rapid heating rate(800 ℃/min), normal heating rate(30 ℃/min) and in the presence or absence of ZnO, was studied. The results show that the decomposition temperature of CaCO3, the temperature of appearance of liquid phase and the f-CaO content descend when the grain size of CaCO3 and SiO2 becomes smaller, which attributes to the reactive activity enhancement of powders due to the decrease of the particle size. When the grain size of CaCO3 and SiO2 is below 1 μm, the rate of the formation of C3S is greatly raised. A rapid sintering rate and the presence of ZnO have an important effect on the formation of C3S and can lower the temperature of the formation of C3S by about 50 ℃.
基金supported by the National Natural Science Foundation of China (No.51205190)the Fundamental Research Funds for the Central Universities (No.NS2016026)+1 种基金the Aeronautical Power Science Fund Project (No. 6141B090317)the Innovation Fund of Jiangsu Province, China (No.KYLX-0304)
文摘In order to investigate the elastic properties of directionally solidified(DS)superalloys,an elasticity model called boundaries elastic model(GBE model),considering grain boundaries and tensile orientations,is proposed in this paper.Two assumptions are adopted in the GBE model:(1)The displacement of grains,which moves along the perpendicular direction,is restricted by the grain boundaries;(2)Grain boundaries influence region(GBIR)is formed around the grain boundaries.Based on the single crystal(SC)calculation method of elastic properties,the GBE model can well predict macroscopic equivalent elastic modulus(Young’s modulus)of DS superalloys under different tensile orientations effectively.To demonstrate the correctness of the GBE model,3D finite element simulation is adopted and tensile experiments on a Ni3Al?base DS superalloy(IC10)along five tensile orientations are carried out.Meanwhile,the grain boundaries are observed by light microscopy and transmission electron microscope(TEM).Therefore,the GBE model is proved to be feasible by comparing the simulated results with the experiments.
文摘Yeasts resulting from the brewing process (RBY) are a valuable by-product, with an important content of minerals, vitamins and, especially, proteins. The purpose of the research was the electroactivation of RBY and the simultaneous obtaining of two products</span><span style="font-family:"">—<span>protein concentrates and hydrolyzed protein fr<span>om residual brewer’s yeast. Electroactivation is a non-residual process, wit</span>hout the use of chemical reagents and relatively inexpensive. The variation of the electroactivation conditions allowed the separation of 90% - 94% of the proteins in the form of protein concentrates. During the process, it is attested to increase the pH value and decrease the redox potential, which characterizes the multiple redox processes that take place in the cathode cell, including sedimentation at the isoelectric point. The presence of albumin in the protein fractions of RBY allows the formation of protein complexes with calcium, attributing a higher biological value to the obtained products.
文摘为了降低电子传输层(Electron transport layer,ETL)与钙钛矿层之间的界面缺陷态密度,通过旋涂法在氧化铟锡(Indium tin oxide,ITO)透明导电玻璃上制备一层SnO_(2)电子传输层,并在其上表面旋涂(NH_(4))_(2)S以修饰SnO_(2)和钙钛矿光吸收层之间的界面。通过X射线光电子能谱、扫描电子显微镜、电化学阻抗谱等表征手段分析(NH_(4))_(2)S修饰对钙钛矿太阳能电池(Perovskite solar cells,PSCs)光电性能的影响。结果表明:NH_(4)^(+)降低了SnO_(2)的表面羟基(—OH)缺陷态密度,增强了界面的疏水性,减少了钙钛矿的形核位点,增大了钙钛矿晶粒;S^(2-)填补了SnO_(2)表面的氧空位(OV),同时部分S^(2-)还与未配位Pb^(2+)连接减少界面处Pb缺陷,抑制了界面处载流子复合;经过(NH_(4))_(2)S的修饰,PSCs开路电压从1.07 V提高到1.11 V,光电转化效率达到了20.53%。(NH_(4))2S修饰后的PSCs具有更高的光电转化效率、更好的长期稳定性。该研究可为PSCs商业化提供新的思路。
文摘2008 is a year of bumper harvest in summer grain across China. The failure of numerous state-owned grain depots to purchase grain in times of bumper harvest, however, directly threatens grain reserve security and state control over grain prices in the upcoming year. An important factor underpinning the difficulty of state grain depots to purchase grain is the unwillingness of farmers to sell grain due to the excess of the current market price over the government "protected price" aimed at preventing cheap grain from harming farmers. When grassroots grain depots find themselves in trouble, foreign capital stealthily moves in by taking advantage of this situation. To fulfill grain storage tasks and receive various state subsidies, some state-owned grain depots have no alternative but to surreptitiously raise the purchase price. By contrast, some not so courageous state-owned grain depots can only borrow money to finance the purchase of commodity grain at market prices and subsequently figure out a way to pay back such loans. Behind such distorted grain purchase behavior lies a rough and rugged history of grain price reform in China.
文摘Agriculture is the foundation of the national economy,while grain is the cornet stone of that foundation.It is also essential for subsistence and development of the mankind. In recent years,especially since its entry into the WTO, China has been undergoing a period of twists and turns in the development of its grain production and trade which used to be sound and stable.
文摘Grain prices often dominate all other product prices,and an increase in their price is usually considered as a prelude to inflation.The three fairly serious inflations,in 1985,1988-1989,and 1993-1995 respectively,were all preceded by grain price hikes.Furthermore,the money supply surged in the preceding year or during the same year in which these inflations occurred.This year has witnessed the same symptoms. High grain prices,which still have a possibility to go up further,have attracted wide attention across the world,including in China.As early as the end of last year,the State Council issued a circular that mandated the stabilization of grain prices in order to strictly crack down on illegal actions such as dishonest merchants driving up grain prices.One time,five State-level Departments led by National Development and Reform Commission,released an urgent announcement in order to safeguard the stability of grain prices in the domestic market.Wu Xiaoling,Vice Governor of the People's Bank of China,said that the negative influences exerted on other product prices by the rise in global grain price should not be ignored.According to Wu,the People's Bank of China will continue to closely watch the price changes. From a global and comprehensive viewpoint,the article analyzes the features of the recent grain price hike and the reasons for its dramatic rise,as well as,the impact it will have on the global economy.
文摘This paper makes predictions for China’s grain production and its associated supply and demand situation up to 2030 by using input-occupancy-output techniques and systems science methodology. It argues that, taking into account its basic situation and world grain resources, China has no other choice but to count on self-sufficiency in terms of grain supply.
文摘In China’s countryside today, so far the foodstuffs for daily-life subsistence are still taken from the traditional farming production in addition to the yield of animal husbandry, while crop plantation takes the lion’s share in our rural economy. During the Medieval Age of the Western countries, however, special stress was placed on raising livestock on pastureland until the Industrial Revolution occurred in the 18th century when grain-oriented agriculture came into being. As a result of the unprecedented boom of modern science and technology now sweeping the whole world, farming productivity has sky-