Based on the form of the n-dimensional generic power-law potential, the state equation and the heat capacity, the analytical expressions of the Joule-Thomson coefficient （3TC） for an ideal Bose gas are derived in n-...Based on the form of the n-dimensional generic power-law potential, the state equation and the heat capacity, the analytical expressions of the Joule-Thomson coefficient （3TC） for an ideal Bose gas are derived in n-dimensional potential. The effect of the spatial dimension and the external potential on the JTC are discussed, respectively. These results show that： （i） For the free ideal Bose gas, when n/s ≤ 2 （n is the spatial dimension, s is the momentum index in the relation between the energy and the momentum）, and T → Tc （Tc is the critical temperature）, the JTC can obviously improve by means of changing the throttle valve＇s shape and decreasing the spatial dimension of gases. （ii） For the inhomogeneous external potential, the discriminant △= [1 - y∏^ni=1（kT/εi）^1/tiГ（1/ti＋1）] （k is the Boltzmann Constant, T is the thermodynamic temperature, ε is the external field＇s energy）, is obtained. The potential makes the JTC increase when △ 〉 0, on the contrary, it makes the JTC decrease when A 〈△. （iii） In the homogenous strong external potential, the JTC gets the maximum on the condition of kTεi〈〈1.展开更多
Based on the evolution of geological dynamics and spatial chaos theory, we proposed the advanced prediction an advanced prediction method of a gas desorption index of drill cuttings to predict coal and gas outbursts. ...Based on the evolution of geological dynamics and spatial chaos theory, we proposed the advanced prediction an advanced prediction method of a gas desorption index of drill cuttings to predict coal and gas outbursts. We investigated and verified the prediction method by a spatial series data of a gas desorption index of drill cuttings obtained from the 113112 coal roadway at the Shitai Mine. Our experimental results show that the spatial distribution of the gas desorption index of drill cuttings has some chaotic charac- teristics, which implies that the risk of coal and gas outbursts can be predicted by spatial chaos theory. We also found that a proper amount of sample data needs to be chosen in order to ensure the accuracy and practical maneuverability of prediction. The relative prediction error is small when the prediction pace is chosen carefully. In our experiments, it turned out that the optimum number of sample points is 80 and the optimum prediction pace 30. The corresponding advanced prediction pace basically meets the requirements of engineering applications.展开更多
To study effect of C2H2 and change of headspace gas on N2O emission, denitrification, as well as CO2emission, slumes of an agricultural soil were anaerobically incubated for 7 da3’s at 25 ℃. Both N2O reduction and C...To study effect of C2H2 and change of headspace gas on N2O emission, denitrification, as well as CO2emission, slumes of an agricultural soil were anaerobically incubated for 7 da3’s at 25 ℃. Both N2O reduction and CO2 emissions were inhibited by the addition of 100 mL L-1 of C2H2. However, the inhibition to CO2 emission was alleviated by the replacement of headspace gas, and the N2O emission was enhanced by the replacement. Acetylene disappeared evidently from the soil slumes during the incubation. Consequently results obtained from the traditional C2H2 blocking technique for determination of denitrification rate, especially in a long-time incubation, should be explained with care because of its side effect existing in the incubation environments without change of headspace gas. To reduce the possible side effect on the processes other than denitrification, it is suggested that headspace gas should be replaced several times during a long-time incubation.展开更多
Nowadays, cities are the main living environment of human beings. Rapid urbanization is associated with a variety of issues： population explosion, urban heat island effect, greenhouse gases emissions, energy crisis, ...Nowadays, cities are the main living environment of human beings. Rapid urbanization is associated with a variety of issues： population explosion, urban heat island effect, greenhouse gases emissions, energy crisis, climate change and so on. To deal with the challenges from the huge energy consumption and GHGs （greenhouse gases） emission, more and more attention has been paid to low carbon eco-city in China. In this research, the whole process is linked by low carbon eco-city development. High-resolution thermal IR （infrared） satellite remote-sensing is introduced to land use and urban heat island monitoring to meet the requirement of higher accuracy. GIS （geo-information science） technology provides a framework for collecting, processing, managing, analyzing and sharing spatial and temporal data. It has been used in spatial and temporal database management and analysis in low carbon eco-city study. The integrated geo-information system proposed in this research, which will be introduced to various government agencies in China, could enrich the concepts and means for the construction of low carbon eco^city.展开更多
The hypothesis that bacteria and protozoa microorganisms are able to travel from one planet to another and become of exolife was not taken seriously by the scientific community for a long time. However at the end of t...The hypothesis that bacteria and protozoa microorganisms are able to travel from one planet to another and become of exolife was not taken seriously by the scientific community for a long time. However at the end of the 20th century the situation changed dramatically. Firstly, in 1990, meteorites consisting of Martian rocks were found. Secondly, it became clear that many microorganisms especially bacteria spores have an uncanny ability to endure the rugged environment of the outer space for a long time and then re-activate in a more favorable environment. If we compare these findings, the idea of interplanetary transmigration of the simplest forms of life on meteoroids ceases to look so illusory. The final dot in this issue was made by the works of academician Rozanov, and later Hoover （Professor Richard B. Hoover） through the discovery of fossilized microbes inside of a meteorite massif, that is to say, seeds of life. However, to tie only the simplest forms of life to meteorites or comets is to introduce strong constraints on the likelihood of delivery of seeds （spores of life） to Earth for many obvious reasons. Besides, exobiology does not negate the problem of origin of life, and transfers it into the era of the young universe. Therefore, it is necessary to consider in detail the essence of seeds of life or cosmic particles of dust and gas-dust streams as their carriers, their penetration path to Earth and forms of their existence.展开更多
基金Supported by Natural Science Foundation of Shaanxi Province under Grant No. 2007A02the Science Foundation of Baoji University of Science and Arts of China under Grant No. ZK0914
文摘Based on the form of the n-dimensional generic power-law potential, the state equation and the heat capacity, the analytical expressions of the Joule-Thomson coefficient （3TC） for an ideal Bose gas are derived in n-dimensional potential. The effect of the spatial dimension and the external potential on the JTC are discussed, respectively. These results show that： （i） For the free ideal Bose gas, when n/s ≤ 2 （n is the spatial dimension, s is the momentum index in the relation between the energy and the momentum）, and T → Tc （Tc is the critical temperature）, the JTC can obviously improve by means of changing the throttle valve＇s shape and decreasing the spatial dimension of gases. （ii） For the inhomogeneous external potential, the discriminant △= [1 - y∏^ni=1（kT/εi）^1/tiГ（1/ti＋1）] （k is the Boltzmann Constant, T is the thermodynamic temperature, ε is the external field＇s energy）, is obtained. The potential makes the JTC increase when △ 〉 0, on the contrary, it makes the JTC decrease when A 〈△. （iii） In the homogenous strong external potential, the JTC gets the maximum on the condition of kTεi〈〈1.
基金Financial support for this work, provided by the National Basic Research Program of China (No.2011CB201204)the National Youth Science Foundation Program (No.50904068)+1 种基金the Heilongjiang Science & Technology Scientific Research Foundation Program for the Eighth Introduction of Talent (No.06-26)the National Engineering Research Center for Coal Gas Control
文摘Based on the evolution of geological dynamics and spatial chaos theory, we proposed the advanced prediction an advanced prediction method of a gas desorption index of drill cuttings to predict coal and gas outbursts. We investigated and verified the prediction method by a spatial series data of a gas desorption index of drill cuttings obtained from the 113112 coal roadway at the Shitai Mine. Our experimental results show that the spatial distribution of the gas desorption index of drill cuttings has some chaotic charac- teristics, which implies that the risk of coal and gas outbursts can be predicted by spatial chaos theory. We also found that a proper amount of sample data needs to be chosen in order to ensure the accuracy and practical maneuverability of prediction. The relative prediction error is small when the prediction pace is chosen carefully. In our experiments, it turned out that the optimum number of sample points is 80 and the optimum prediction pace 30. The corresponding advanced prediction pace basically meets the requirements of engineering applications.
文摘To study effect of C2H2 and change of headspace gas on N2O emission, denitrification, as well as CO2emission, slumes of an agricultural soil were anaerobically incubated for 7 da3’s at 25 ℃. Both N2O reduction and CO2 emissions were inhibited by the addition of 100 mL L-1 of C2H2. However, the inhibition to CO2 emission was alleviated by the replacement of headspace gas, and the N2O emission was enhanced by the replacement. Acetylene disappeared evidently from the soil slumes during the incubation. Consequently results obtained from the traditional C2H2 blocking technique for determination of denitrification rate, especially in a long-time incubation, should be explained with care because of its side effect existing in the incubation environments without change of headspace gas. To reduce the possible side effect on the processes other than denitrification, it is suggested that headspace gas should be replaced several times during a long-time incubation.
文摘Nowadays, cities are the main living environment of human beings. Rapid urbanization is associated with a variety of issues： population explosion, urban heat island effect, greenhouse gases emissions, energy crisis, climate change and so on. To deal with the challenges from the huge energy consumption and GHGs （greenhouse gases） emission, more and more attention has been paid to low carbon eco-city in China. In this research, the whole process is linked by low carbon eco-city development. High-resolution thermal IR （infrared） satellite remote-sensing is introduced to land use and urban heat island monitoring to meet the requirement of higher accuracy. GIS （geo-information science） technology provides a framework for collecting, processing, managing, analyzing and sharing spatial and temporal data. It has been used in spatial and temporal database management and analysis in low carbon eco-city study. The integrated geo-information system proposed in this research, which will be introduced to various government agencies in China, could enrich the concepts and means for the construction of low carbon eco^city.
文摘The hypothesis that bacteria and protozoa microorganisms are able to travel from one planet to another and become of exolife was not taken seriously by the scientific community for a long time. However at the end of the 20th century the situation changed dramatically. Firstly, in 1990, meteorites consisting of Martian rocks were found. Secondly, it became clear that many microorganisms especially bacteria spores have an uncanny ability to endure the rugged environment of the outer space for a long time and then re-activate in a more favorable environment. If we compare these findings, the idea of interplanetary transmigration of the simplest forms of life on meteoroids ceases to look so illusory. The final dot in this issue was made by the works of academician Rozanov, and later Hoover （Professor Richard B. Hoover） through the discovery of fossilized microbes inside of a meteorite massif, that is to say, seeds of life. However, to tie only the simplest forms of life to meteorites or comets is to introduce strong constraints on the likelihood of delivery of seeds （spores of life） to Earth for many obvious reasons. Besides, exobiology does not negate the problem of origin of life, and transfers it into the era of the young universe. Therefore, it is necessary to consider in detail the essence of seeds of life or cosmic particles of dust and gas-dust streams as their carriers, their penetration path to Earth and forms of their existence.
