Bryopsis kypnoides Lamouroux is a unique intertidal siphonous green alga whose extruded protoplasm can aggregate spontaneously in seawater to form numerous new cells that can develop into mature algal thalli. In this ...Bryopsis kypnoides Lamouroux is a unique intertidal siphonous green alga whose extruded protoplasm can aggregate spontaneously in seawater to form numerous new cells that can develop into mature algal thalli. In this study, the photosynthetic responses during dehydration of both the thalli and protoplasts isolated from B. kypnoides were measured using a Dual-PAM （pulse amplitude modulation）-100 fluorometer. The results show that the photosynthetic rates of B. kypnoides thalli were maintained for an initial period, beyond which continued desiccation resulted in reduced rates of PSI and PSII. However, the photosynthetic performances of the isolated protoplasts dehydrated in air （CO2 concentration 600-700 mg/L） showed a slight increase of Y（II） at 20% water loss, but the rates decreased thereafter with declining water content. When protoplasts were dehydrated in CO2 deficient conditions （CO2 concentration 40-80 mg/L）, the values of Y（II） declined steadily with increased dehydration without an initial rise. These results indicated that the thalli and isolated protoplasts of this alga can utilize CO2 in ambient air effectively, and the photosynthetic performances of the isolated protoplasts were significantly different from that of the thalli during dehydration. Thus the protoplasts may be an excellent system for the study of stress tolerance.展开更多
Extreme freeze-thaw action occurs on the Qinghai-Tibet Plateau due to its unique climate resulting from high elevation and cold temperature.This action causes damage to the surface soil structure, as soil erosion in t...Extreme freeze-thaw action occurs on the Qinghai-Tibet Plateau due to its unique climate resulting from high elevation and cold temperature.This action causes damage to the surface soil structure, as soil erosion in the Qinghai-Tibet Plateau is dominated by freeze-thaw erosion.In this research,freezing–thawing process of the soil samples collected from the Qinghai–Tibet Plateau was carried out by laboratory experiments to determinate the volume variation of soil as well as physical and mechanical properties, such as porosity, granularity and uniaxial compressive strength, after the soil experiences various freeze–thaw cycles.Results show that cohesion and uniaxial compressive strength decreased as the volume and porosity of the soil increased after experiencing various freeze–thaw cycles, especially in the first six freeze–thaw cycles.Consequently, the physical and mechanical properties of the soil were altered.However, granularity and internal friction angle did not vary significantly with an increase in the freeze–thaw cycle.The structural damage among soil particles due to frozen water expansion was the major cause of changes in soil mechanical behavior in the Qinghai–Tibet Plateau.展开更多
Significant attention has been given to biogas production, purification and upgrading as a renewable and clean fuel supplement. Biogas is a product of an anaerobic digestion process comprising methane, carbon dioxide,...Significant attention has been given to biogas production, purification and upgrading as a renewable and clean fuel supplement. Biogas is a product of an anaerobic digestion process comprising methane, carbon dioxide,and trace amounts of other gases. Biogas purification removes trace gases in biogas for safe utilisation. Biogas upgrading produces methane-rich biogas by removing bulk carbon dioxide from the gas mixture. Several carbon dioxide removal techniques can be applied for biogas upgrading. However, chemical absorption of carbon dioxide for biogas upgrading is of special significance due to its operation at ambient or near ambient temperature and pressure, thus reducing energy consumption. This paper reviews the chemical absorption of carbon dioxide using amine scrubbing, caustic solvent scrubbing, and amino acid salt solution scrubbing. Each of these techniques for biogas upgrading is discussed. The paper concludes that an optimised implementation of the chemical absorption techniques for biogas upgrading requires further research.展开更多
This paper mainly discusses the multiscale computation from a chemical engineering perspective.From the application designer's perspective,we propose a new approach to investigate and develop both flexible and eff...This paper mainly discusses the multiscale computation from a chemical engineering perspective.From the application designer's perspective,we propose a new approach to investigate and develop both flexible and efficient computer architectures. Based on the requirements of applications within one category,we first induce and extract some inherent computing patterns or core computing kernels from the applications.Some computing models and innovative computing architectures will then be developed for these patterns or kernels,as well as the software mapping techniques. Finally those applications which can share and utilize those computing patterns or kernels can be executed very efficiently on those novel computing architectures. We think that the proposed approach may not be achievable within the existing technology. However,we believe that it will be available in the near future. Hence,we will describe this approach from the following four aspects:multiscale environment in the world,mesoscale as a key scale,energy minimization multiscale(EMMS)paradigm and our perspective.展开更多
In this paper, we evaluate the general solutions for plane-symmetric thick domain walls in Lyra geometry in presence of bulk viscous fluid. Expressions for the energy density and pressure of domain walls are derived i...In this paper, we evaluate the general solutions for plane-symmetric thick domain walls in Lyra geometry in presence of bulk viscous fluid. Expressions for the energy density and pressure of domain walls are derived in both cases of uniform and time varying displacement field β. Some physical consequences of the models are also given. Finally, the geodesic equations and acceleration of the test particle are discussed.展开更多
By testing the temperature of the coal and the stress of the working surface, we got the variation law of coal temperature and coal stress during the excavation. The result shows that the activities of mining affect t...By testing the temperature of the coal and the stress of the working surface, we got the variation law of coal temperature and coal stress during the excavation. The result shows that the activities of mining affect the coal temperature, the fluctuation of coal temperature and the coal stress is synchronous. During the smooth change of crustal stress, the coal temperature basically keeps unchanged, when the dynamic phenomenon appears, the coal temperature changes, as well the coal stress. Therefore, we can use the online coal temperature monitoring system to test the coal temperature of the working surface continuously, and it can provide basic information for forecasting coal mine power disaster before it happens.展开更多
Thermodynamically, electric storages can be generally characterized as a type of regenerative machines able to operate in a work and a power machine mode. A consideration of the concentration term of the Nernst equati...Thermodynamically, electric storages can be generally characterized as a type of regenerative machines able to operate in a work and a power machine mode. A consideration of the concentration term of the Nernst equation already shows a first principal difference between batch and flow processes, because the reaction coordinate depends on time for batch processes and on the flow coordinate for flow processes. Ionic substances may be stored within a volume surrounding the electrodes or on the surface of the electrodes itself. The volume concentrations of the reactants are thus a determining parameter of electrochemical storage beside voltage and the ratio of released electrons per reacting reference substance. Surface storage allows only batch processes while volume storage allows batch and flow processes. This characterization identifies the benefits of certain reactions regarding mass and volume related energy density in a simple way at a very early stage of development. It also allows a simple calculation of possible discharging times.展开更多
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to dire...Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of^(25)Mg(p,γ)^(26)Al,^(19)F(p,α)^(16)O,^(13)C(α,n)^(16)O and ^(12)C(α,γ)^(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given.展开更多
基金Supported by the National Natural Science Foundation of China(Nos. 30970302,40806063,30830015,B49082401)
文摘Bryopsis kypnoides Lamouroux is a unique intertidal siphonous green alga whose extruded protoplasm can aggregate spontaneously in seawater to form numerous new cells that can develop into mature algal thalli. In this study, the photosynthetic responses during dehydration of both the thalli and protoplasts isolated from B. kypnoides were measured using a Dual-PAM （pulse amplitude modulation）-100 fluorometer. The results show that the photosynthetic rates of B. kypnoides thalli were maintained for an initial period, beyond which continued desiccation resulted in reduced rates of PSI and PSII. However, the photosynthetic performances of the isolated protoplasts dehydrated in air （CO2 concentration 600-700 mg/L） showed a slight increase of Y（II） at 20% water loss, but the rates decreased thereafter with declining water content. When protoplasts were dehydrated in CO2 deficient conditions （CO2 concentration 40-80 mg/L）, the values of Y（II） declined steadily with increased dehydration without an initial rise. These results indicated that the thalli and isolated protoplasts of this alga can utilize CO2 in ambient air effectively, and the photosynthetic performances of the isolated protoplasts were significantly different from that of the thalli during dehydration. Thus the protoplasts may be an excellent system for the study of stress tolerance.
基金funded by the National Natural Science Foundation of China(Grant No.41401611,41301072)China Postdoctoral Science Foundation(Grant No.2014M560817,2015T81069)the Open Project Program of the State Key Laboratory of Frozen Soil Engineering(Grant No.SKLFSE201208)
文摘Extreme freeze-thaw action occurs on the Qinghai-Tibet Plateau due to its unique climate resulting from high elevation and cold temperature.This action causes damage to the surface soil structure, as soil erosion in the Qinghai-Tibet Plateau is dominated by freeze-thaw erosion.In this research,freezing–thawing process of the soil samples collected from the Qinghai–Tibet Plateau was carried out by laboratory experiments to determinate the volume variation of soil as well as physical and mechanical properties, such as porosity, granularity and uniaxial compressive strength, after the soil experiences various freeze–thaw cycles.Results show that cohesion and uniaxial compressive strength decreased as the volume and porosity of the soil increased after experiencing various freeze–thaw cycles, especially in the first six freeze–thaw cycles.Consequently, the physical and mechanical properties of the soil were altered.However, granularity and internal friction angle did not vary significantly with an increase in the freeze–thaw cycle.The structural damage among soil particles due to frozen water expansion was the major cause of changes in soil mechanical behavior in the Qinghai–Tibet Plateau.
文摘Significant attention has been given to biogas production, purification and upgrading as a renewable and clean fuel supplement. Biogas is a product of an anaerobic digestion process comprising methane, carbon dioxide,and trace amounts of other gases. Biogas purification removes trace gases in biogas for safe utilisation. Biogas upgrading produces methane-rich biogas by removing bulk carbon dioxide from the gas mixture. Several carbon dioxide removal techniques can be applied for biogas upgrading. However, chemical absorption of carbon dioxide for biogas upgrading is of special significance due to its operation at ambient or near ambient temperature and pressure, thus reducing energy consumption. This paper reviews the chemical absorption of carbon dioxide using amine scrubbing, caustic solvent scrubbing, and amino acid salt solution scrubbing. Each of these techniques for biogas upgrading is discussed. The paper concludes that an optimised implementation of the chemical absorption techniques for biogas upgrading requires further research.
文摘This paper mainly discusses the multiscale computation from a chemical engineering perspective.From the application designer's perspective,we propose a new approach to investigate and develop both flexible and efficient computer architectures. Based on the requirements of applications within one category,we first induce and extract some inherent computing patterns or core computing kernels from the applications.Some computing models and innovative computing architectures will then be developed for these patterns or kernels,as well as the software mapping techniques. Finally those applications which can share and utilize those computing patterns or kernels can be executed very efficiently on those novel computing architectures. We think that the proposed approach may not be achievable within the existing technology. However,we believe that it will be available in the near future. Hence,we will describe this approach from the following four aspects:multiscale environment in the world,mesoscale as a key scale,energy minimization multiscale(EMMS)paradigm and our perspective.
文摘In this paper, we evaluate the general solutions for plane-symmetric thick domain walls in Lyra geometry in presence of bulk viscous fluid. Expressions for the energy density and pressure of domain walls are derived in both cases of uniform and time varying displacement field β. Some physical consequences of the models are also given. Finally, the geodesic equations and acceleration of the test particle are discussed.
文摘By testing the temperature of the coal and the stress of the working surface, we got the variation law of coal temperature and coal stress during the excavation. The result shows that the activities of mining affect the coal temperature, the fluctuation of coal temperature and the coal stress is synchronous. During the smooth change of crustal stress, the coal temperature basically keeps unchanged, when the dynamic phenomenon appears, the coal temperature changes, as well the coal stress. Therefore, we can use the online coal temperature monitoring system to test the coal temperature of the working surface continuously, and it can provide basic information for forecasting coal mine power disaster before it happens.
文摘Thermodynamically, electric storages can be generally characterized as a type of regenerative machines able to operate in a work and a power machine mode. A consideration of the concentration term of the Nernst equation already shows a first principal difference between batch and flow processes, because the reaction coordinate depends on time for batch processes and on the flow coordinate for flow processes. Ionic substances may be stored within a volume surrounding the electrodes or on the surface of the electrodes itself. The volume concentrations of the reactants are thus a determining parameter of electrochemical storage beside voltage and the ratio of released electrons per reacting reference substance. Surface storage allows only batch processes while volume storage allows batch and flow processes. This characterization identifies the benefits of certain reactions regarding mass and volume related energy density in a simple way at a very early stage of development. It also allows a simple calculation of possible discharging times.
基金supported by the National Natural Science Foundation of China(Grant Nos.11490560 and 11321064)the National Basic Research Program of China(Grant No.2013CB834406)
文摘Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of^(25)Mg(p,γ)^(26)Al,^(19)F(p,α)^(16)O,^(13)C(α,n)^(16)O and ^(12)C(α,γ)^(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given.
