In order to describe the relationship between dynamic process and sludge removing load in active sludge system, a new method for designing the volume of aeration tanks was put forward based on the Michaelis and Menten...In order to describe the relationship between dynamic process and sludge removing load in active sludge system, a new method for designing the volume of aeration tanks was put forward based on the Michaelis and Menten equation. the influence of sludge returning was considered in the design. The result shows that the parameter of sludge reflux ratio plays a very important role in the design of active sludge system. In some given conditions,there exists an optimum reflux ratio which can make the volume of aeration tank be the minimum.展开更多
Sperm of sea cucumber Apostichopus japonicus (Selenka) were quiescent in electrolyte NaCl solution and artificial seawater (ASW) and nonelectrolyte glucose and mannitol solutions when the osmolality was less than 200 ...Sperm of sea cucumber Apostichopus japonicus (Selenka) were quiescent in electrolyte NaCl solution and artificial seawater (ASW) and nonelectrolyte glucose and mannitol solutions when the osmolality was less than 200 mOsm kg-1. The sperm started to be motile as a result of increased osmolality, indicating an osmolality-dependent initiation of sperm motility in sea cucumber. After a brief incubation in hypotonic NaCl and glucose solutions with osmolalities of 200 and 400 mOsm kg-1, sperm lost partial motile ability. Sperm became immobilized when pH was 6.0 in NaCl, glucose and mannitol solutions, suggesting that an H+ release is involved in sperm activation. The decreased pH had no effect on the percentage of motile sperm in ASW, whereas it delayed the time period to reach the maximum motility (motilitymax). Extracellular Ca2+ in electrolyte solutions was not essential for motility stimulation but shortened the time of reaching motilitymax. When Ca2+ was mixed in nonelectrolyte solutions the sperm motility was completely suppressed. The K+ channel blocker, quinine, suppressed the sperm motility in electrolyte solution, showing a possible involvement of K+ transport in the process. High K+ concentration did not affect the sperm motility in NaCl solution, but decreased it in ASW and almost entirely suppressed it in nonelectrolyte solutions. The different effects of pH and K+ in ASW and NaCl solution indicate that external ions may also regulate sperm motility.展开更多
The rapid expansion of human resources has caused damage to our living environment. The concept of green economy with low power consumption and low pollution is becoming the focus of global attention. This article rev...The rapid expansion of human resources has caused damage to our living environment. The concept of green economy with low power consumption and low pollution is becoming the focus of global attention. This article reviews the development of green supply chain management （GSCM）, and briefly introduces the current methods of GSCM. In order to implement GSCM in the round, this paper recommends the life-cycle analysis, and proposed GSCM methods which the different types of companies should adopt.展开更多
The paper summarizes the research progresses of electrical capacitance and electrical resistance assessing tree vigor and points out the development direction of the study. Researches show that electrical capacitance ...The paper summarizes the research progresses of electrical capacitance and electrical resistance assessing tree vigor and points out the development direction of the study. Researches show that electrical capacitance is related to the indexes of periodic growth rate of trees, foliar biomass and diameter of breast height, while electrical resistance has inverse relationships with the above indexes. Eiectrical capacitance and electrical resistance change when trees suffer environmental stress, insect pests or diseases. Especially, changes of electrical resistance are observed before symptom expression of some tree diseases, which can help to establish a certain disease potential hazard rating system. Mechanisms of electrical capacitance and resistance assessing tree vigor, especially in molecule level, still need to be studied and the application criteria of electrical resistance and capacitance need to be established.展开更多
文摘In order to describe the relationship between dynamic process and sludge removing load in active sludge system, a new method for designing the volume of aeration tanks was put forward based on the Michaelis and Menten equation. the influence of sludge returning was considered in the design. The result shows that the parameter of sludge reflux ratio plays a very important role in the design of active sludge system. In some given conditions,there exists an optimum reflux ratio which can make the volume of aeration tank be the minimum.
基金supported by an 863 High Technology Project (No. 2006AA10A411) from the Chinese Ministry of Science and Technologyan NSFC grant (No. 30571417)
文摘Sperm of sea cucumber Apostichopus japonicus (Selenka) were quiescent in electrolyte NaCl solution and artificial seawater (ASW) and nonelectrolyte glucose and mannitol solutions when the osmolality was less than 200 mOsm kg-1. The sperm started to be motile as a result of increased osmolality, indicating an osmolality-dependent initiation of sperm motility in sea cucumber. After a brief incubation in hypotonic NaCl and glucose solutions with osmolalities of 200 and 400 mOsm kg-1, sperm lost partial motile ability. Sperm became immobilized when pH was 6.0 in NaCl, glucose and mannitol solutions, suggesting that an H+ release is involved in sperm activation. The decreased pH had no effect on the percentage of motile sperm in ASW, whereas it delayed the time period to reach the maximum motility (motilitymax). Extracellular Ca2+ in electrolyte solutions was not essential for motility stimulation but shortened the time of reaching motilitymax. When Ca2+ was mixed in nonelectrolyte solutions the sperm motility was completely suppressed. The K+ channel blocker, quinine, suppressed the sperm motility in electrolyte solution, showing a possible involvement of K+ transport in the process. High K+ concentration did not affect the sperm motility in NaCl solution, but decreased it in ASW and almost entirely suppressed it in nonelectrolyte solutions. The different effects of pH and K+ in ASW and NaCl solution indicate that external ions may also regulate sperm motility.
文摘The rapid expansion of human resources has caused damage to our living environment. The concept of green economy with low power consumption and low pollution is becoming the focus of global attention. This article reviews the development of green supply chain management （GSCM）, and briefly introduces the current methods of GSCM. In order to implement GSCM in the round, this paper recommends the life-cycle analysis, and proposed GSCM methods which the different types of companies should adopt.
基金Supported by the National Nature Science Foundation of China (grant No. 30471384 )
文摘The paper summarizes the research progresses of electrical capacitance and electrical resistance assessing tree vigor and points out the development direction of the study. Researches show that electrical capacitance is related to the indexes of periodic growth rate of trees, foliar biomass and diameter of breast height, while electrical resistance has inverse relationships with the above indexes. Eiectrical capacitance and electrical resistance change when trees suffer environmental stress, insect pests or diseases. Especially, changes of electrical resistance are observed before symptom expression of some tree diseases, which can help to establish a certain disease potential hazard rating system. Mechanisms of electrical capacitance and resistance assessing tree vigor, especially in molecule level, still need to be studied and the application criteria of electrical resistance and capacitance need to be established.
