In order to investigate the characteristics of re-oxidation of residual coal in goafs in close coal seam mining,scanning electron microscope and infrared spectrometer are used to study the changes of coal microstructu...In order to investigate the characteristics of re-oxidation of residual coal in goafs in close coal seam mining,scanning electron microscope and infrared spectrometer are used to study the changes of coal microstructure and chemical reaction of functional groups of eight coal samples at different ranks.Result shows that after initial oxidation,the surface morphology of pore are different,and the porosity of coal is increased and the oxygen adsorption capacity of coal is improved.The change of coal molecular structure and presence of a large amount of active oxygen-containing functional groups lead to increasing tendency of coal to further oxidation.In addition,the higher lever of the initial oxidation is,the easier the re-oxidation occurs.展开更多
This work aimed at studying the feasibility of calculating the coal-oxygen diffusion properties during the low temperature oxidation process of lignite so as to predict its spontaneous combustion process. Coal samples...This work aimed at studying the feasibility of calculating the coal-oxygen diffusion properties during the low temperature oxidation process of lignite so as to predict its spontaneous combustion process. Coal samples were oxidized in air ambient under different temperatures. Scanning Electron Microscope was used to indicate the surface morphology changes of oxidization. Then, based on fractal theory and flow characteristics, the ffactal dimension of gas diffusion in the pore ways was calculated under different temperature. Considering pore size distribution, connectivity distribution and Fick diffusion mechanisms, the relationship between the gas diffusivity change with pore area ffactal dimension and porosity was investigated, and multiple linear equation of the coal- oxygen diffusion coefficients and pore parameters was obtained. Comparison between the experimental data and model prediction verifies the validiW of the model. The research provides a theoretical basis for the prediction model of coal-oxygen diffusion law.展开更多
The Intemational Concordia explorer telescope （ICE-T） is a f/1.1 Schmidt telescope, 61 cm aperture, with two optical tubes equipped with identical charged coupled devices 10.3× 10.3 k, 9μ pixel size, ultra-wi...The Intemational Concordia explorer telescope （ICE-T） is a f/1.1 Schmidt telescope, 61 cm aperture, with two optical tubes equipped with identical charged coupled devices 10.3× 10.3 k, 9μ pixel size, ultra-wide-fieldwith a total FOV of 65 square degrees. Its aim is to operate at Dome C, the French-Italian Antarctic Station, taking advantage of the long winter night for continuous observations. It is optimized for high precision photometry in two separate filters Sloan g and Sloan i ranging from 100 mmag to 10 mmag （from 9 to16 mag）. Among the scientific tasks there are the detection of hot Jupiters and Super Earths with the transit method, and related magnetic activity of the hosting stars. The 4m Radom dome for ICE-T together with 3 foundation pillars and the cables bundle have been already successfully installed in January 2009.展开更多
The developmental process of Myeloma cells under a digital optical microscope has been inspected and monitored by using time-lapsed recording technique. Myeloma cells were cultured in medium contained 20% and 50% of F...The developmental process of Myeloma cells under a digital optical microscope has been inspected and monitored by using time-lapsed recording technique. Myeloma cells were cultured in medium contained 20% and 50% of Fetal Bovine Serum （FBS）, respectively. Inspection and monitoring for 6 hours showed the effect of the FBS to mobility, proliferation rate, and development of cell cycle phases of Myeloma cells. Using time-lapsed data, the speed of cells was 3.5-6.0 pm/s when using FBS 20% and increased to 5.0-8.0 p.m/s when using FBS 50%. The rate of cells decreases from 2 cells/hr when using FBS 20% to 1/6 cells/br when using FBS 50%. The cells division process is signified by the change in gray level and it took every 50-70 minutes.展开更多
Simultaneous multicolor photometry of fast-moving objects is discussed in this paper. In conventional astronomical photometry, the accuracy of flux and color indices of fast-moving objects is affected by the variation...Simultaneous multicolor photometry of fast-moving objects is discussed in this paper. In conventional astronomical photometry, the accuracy of flux and color indices of fast-moving objects is affected by the variations of the targets and weather conditions in space and time domains.We optimize related techniques and methods of observation and data reduction, including image cal- ibration, background fitting, targets detection and location, isophotal photometry, and flux calibration by using background stars from different fields. We consider that simultaneous multicolor data acquisition and differential flux calibration are critical for improving photometric accuracy of fast-moving objects. Our results show the photometric accuracy is better than 5% based on the observations carried out by a 1-meter telescope under ordinary, non-photometric conditions.展开更多
This study briefly describes the targets and problems of the future Japanese project In situ Lunar Orientation Measurement(ILOM),which is planned for the year 2017.One of the important parts of the project is to place...This study briefly describes the targets and problems of the future Japanese project In situ Lunar Orientation Measurement(ILOM),which is planned for the year 2017.One of the important parts of the project is to place a small optical telescope on the Lunar surface with the purpose to detect the Lunar physical libration with unprecedented accuracy 0.001 arcsec.At the present stage of research the computer simulation of future observations is going on,aiming to determine the moments of transition of a star through the first meridian and the polar distance of the star.Rotation of the Moon is being calculated under the analytical theory developed in the frame of a theme of the grant.A list of stars brighter than 12 m,whose coordinates are close to the Lunar precession pole motion,was constructed on the basis of several star catalogues.On average,for each moment of observation in the field of view of the telescope(1°) there are approximately 20-25 stars.Analyses of simulated stellar tracks observable from the Lunar surface(in a polar zone) reveal the significant difference from daily parallels of stars in comparison with the Earth.During one Lunar "day" equal 237 terrestrial days,a star moves on a spiral.However,depending on a longitude of a star,these spirals can be untwisted or twisted.In the latter case a star can describe a loop in the sky of the Moon during the period of supervision.Such an unusual astrometric phenomenon combined with the slow rotation of the Moon is compared with the Earth and the fast precession motion of the Lunar pole(in comparison with the precession motion of a terrestrial pole).展开更多
We use the newly released observational H(z) data (OHD), the Cosmic Microwave Background (CMB) shift parameter, and the Baryon Acoustic Oscillation (BAO) measurements data to constrain cosmological parameters of f(R) ...We use the newly released observational H(z) data (OHD), the Cosmic Microwave Background (CMB) shift parameter, and the Baryon Acoustic Oscillation (BAO) measurements data to constrain cosmological parameters of f(R) gravity in Palatini formalism in which the f(R) form is defined as f(R) = R β/Rn. Under the assumption of a spatially flat FRW universe, we get the best fitting results of the free parameters (Ωm0, n). In the calculation, we marginalize the likelihood function over H0 by integrating the probability density P ∝ e-χ2/2 to obtain the best fitting results and the confidence regions in the Ωm0-n plane. The constraints results of (Ωm0, n) = (0.33, 0.41) by OHD only and (Ωm0, n) = (0.23, 0.08) by the combination of OHD+CMB+BAO both indicate that the universe goes through three last phases, i.e., radiation dominated, matter-dominated, and late time accelerated expansion without introduction of dark energy.展开更多
基金the National Key Foundation for Exploring Scientific Instruments of China(No.2012YQ24012705)the National Natural Science Foundation of China(No.51174113)+2 种基金the special fund for Scientific Research Institutes of China(Nos.2013EG122192 and 2014EG122293)CCTEG Innovation Foundation of China(No. 2014MS030)Shenhua Innovation Foundation of China(No. SHGF-13-07)
文摘In order to investigate the characteristics of re-oxidation of residual coal in goafs in close coal seam mining,scanning electron microscope and infrared spectrometer are used to study the changes of coal microstructure and chemical reaction of functional groups of eight coal samples at different ranks.Result shows that after initial oxidation,the surface morphology of pore are different,and the porosity of coal is increased and the oxygen adsorption capacity of coal is improved.The change of coal molecular structure and presence of a large amount of active oxygen-containing functional groups lead to increasing tendency of coal to further oxidation.In addition,the higher lever of the initial oxidation is,the easier the re-oxidation occurs.
基金Supported by the National Natural Science Foundation of China(51204179,51204182)the Natural Science Foundation of Jiangsu Province,China(BK20141242)
文摘This work aimed at studying the feasibility of calculating the coal-oxygen diffusion properties during the low temperature oxidation process of lignite so as to predict its spontaneous combustion process. Coal samples were oxidized in air ambient under different temperatures. Scanning Electron Microscope was used to indicate the surface morphology changes of oxidization. Then, based on fractal theory and flow characteristics, the ffactal dimension of gas diffusion in the pore ways was calculated under different temperature. Considering pore size distribution, connectivity distribution and Fick diffusion mechanisms, the relationship between the gas diffusivity change with pore area ffactal dimension and porosity was investigated, and multiple linear equation of the coal- oxygen diffusion coefficients and pore parameters was obtained. Comparison between the experimental data and model prediction verifies the validiW of the model. The research provides a theoretical basis for the prediction model of coal-oxygen diffusion law.
文摘The Intemational Concordia explorer telescope （ICE-T） is a f/1.1 Schmidt telescope, 61 cm aperture, with two optical tubes equipped with identical charged coupled devices 10.3× 10.3 k, 9μ pixel size, ultra-wide-fieldwith a total FOV of 65 square degrees. Its aim is to operate at Dome C, the French-Italian Antarctic Station, taking advantage of the long winter night for continuous observations. It is optimized for high precision photometry in two separate filters Sloan g and Sloan i ranging from 100 mmag to 10 mmag （from 9 to16 mag）. Among the scientific tasks there are the detection of hot Jupiters and Super Earths with the transit method, and related magnetic activity of the hosting stars. The 4m Radom dome for ICE-T together with 3 foundation pillars and the cables bundle have been already successfully installed in January 2009.
文摘The developmental process of Myeloma cells under a digital optical microscope has been inspected and monitored by using time-lapsed recording technique. Myeloma cells were cultured in medium contained 20% and 50% of Fetal Bovine Serum （FBS）, respectively. Inspection and monitoring for 6 hours showed the effect of the FBS to mobility, proliferation rate, and development of cell cycle phases of Myeloma cells. Using time-lapsed data, the speed of cells was 3.5-6.0 pm/s when using FBS 20% and increased to 5.0-8.0 p.m/s when using FBS 50%. The rate of cells decreases from 2 cells/hr when using FBS 20% to 1/6 cells/br when using FBS 50%. The cells division process is signified by the change in gray level and it took every 50-70 minutes.
文摘Simultaneous multicolor photometry of fast-moving objects is discussed in this paper. In conventional astronomical photometry, the accuracy of flux and color indices of fast-moving objects is affected by the variations of the targets and weather conditions in space and time domains.We optimize related techniques and methods of observation and data reduction, including image cal- ibration, background fitting, targets detection and location, isophotal photometry, and flux calibration by using background stars from different fields. We consider that simultaneous multicolor data acquisition and differential flux calibration are critical for improving photometric accuracy of fast-moving objects. Our results show the photometric accuracy is better than 5% based on the observations carried out by a 1-meter telescope under ordinary, non-photometric conditions.
基金supported by the Russian-Japanese Grant RFFI-JSPS 09-02-92113-ЯΦ_a (2009-2010)the National Natural Science Foundation of China (Grant Nos.11010144 and 10973031)the Chinese National High-Tech Projects (Grant No.2010AA122206)
文摘This study briefly describes the targets and problems of the future Japanese project In situ Lunar Orientation Measurement(ILOM),which is planned for the year 2017.One of the important parts of the project is to place a small optical telescope on the Lunar surface with the purpose to detect the Lunar physical libration with unprecedented accuracy 0.001 arcsec.At the present stage of research the computer simulation of future observations is going on,aiming to determine the moments of transition of a star through the first meridian and the polar distance of the star.Rotation of the Moon is being calculated under the analytical theory developed in the frame of a theme of the grant.A list of stars brighter than 12 m,whose coordinates are close to the Lunar precession pole motion,was constructed on the basis of several star catalogues.On average,for each moment of observation in the field of view of the telescope(1°) there are approximately 20-25 stars.Analyses of simulated stellar tracks observable from the Lunar surface(in a polar zone) reveal the significant difference from daily parallels of stars in comparison with the Earth.During one Lunar "day" equal 237 terrestrial days,a star moves on a spiral.However,depending on a longitude of a star,these spirals can be untwisted or twisted.In the latter case a star can describe a loop in the sky of the Moon during the period of supervision.Such an unusual astrometric phenomenon combined with the slow rotation of the Moon is compared with the Earth and the fast precession motion of the Lunar pole(in comparison with the precession motion of a terrestrial pole).
基金supported by the National Natural Science Foundation of China (Grant Nos. 10773002 and 10875012)the Scientific Research Foundation of Beijing Normal University (Grant No. 105116)
文摘We use the newly released observational H(z) data (OHD), the Cosmic Microwave Background (CMB) shift parameter, and the Baryon Acoustic Oscillation (BAO) measurements data to constrain cosmological parameters of f(R) gravity in Palatini formalism in which the f(R) form is defined as f(R) = R β/Rn. Under the assumption of a spatially flat FRW universe, we get the best fitting results of the free parameters (Ωm0, n). In the calculation, we marginalize the likelihood function over H0 by integrating the probability density P ∝ e-χ2/2 to obtain the best fitting results and the confidence regions in the Ωm0-n plane. The constraints results of (Ωm0, n) = (0.33, 0.41) by OHD only and (Ωm0, n) = (0.23, 0.08) by the combination of OHD+CMB+BAO both indicate that the universe goes through three last phases, i.e., radiation dominated, matter-dominated, and late time accelerated expansion without introduction of dark energy.
