Potash is one of the long-term scare deposits in China,and potash prospecting has long been listed as a key brainstorm project for our nation and geological prospecting units.There have been considerable studies in se...Potash is one of the long-term scare deposits in China,and potash prospecting has long been listed as a key brainstorm project for our nation and geological prospecting units.There have been considerable studies in search for potash deposits in the Kuqa depression of the Tarim basin(Jackson et al.,1991;Gemmer et al.,2004;Vendeville,2005;Vendeville and Jackson,1992a,1992b),展开更多
Underground salt cavern reservoirs are ideal spaces for energy storage. China is rich in salt rock resources with layered lacustrine sedimentary structures. However, the dissolution mechanism of layered salt rocks rem...Underground salt cavern reservoirs are ideal spaces for energy storage. China is rich in salt rock resources with layered lacustrine sedimentary structures. However, the dissolution mechanism of layered salt rocks remains poorly understood, resulting in significant differences between the actual measurements and the designed indices for the layered salt rock water-soluble cavity-making cycle and the cavity shape. In this work, the dissolution rates of 600 groups of layered salt rocks in China under different conditions were determined experimentally.Thus, the established artificial neural network prediction model was used to assess the effects of the contents of NaCl, Na2 SO4, and CaSO4 in the salt rocks, concentrations, dissolution angles, and flow rates on their dissolution rates by performing ANOVA and F-test. The results provide a theoretical basis for evaluating the dissolution rate of layered salt rocks under different conditions and for the numerical simulation of the layered salt rock water-soluble cavity-making process.展开更多
A spiro-type quaternary ammonium salt, spiro-(1,1′)-bipyrrolidinium tetrafluoroborate(SBP-BF4) was successfully prepared by an economical and efficient three-step process comprising the cyclization reaction of 1,4-di...A spiro-type quaternary ammonium salt, spiro-(1,1′)-bipyrrolidinium tetrafluoroborate(SBP-BF4) was successfully prepared by an economical and efficient three-step process comprising the cyclization reaction of 1,4-dibromobutane and pyrrolidine, and subsequent ion exchange pathway with KOH followed by neutralization reaction via HBF4 in the system of ethanol solution. 1H NMR, 13 C NMR, FI-IR and XPS analyses showed the structure of SBP-BF4. The as-obtained SBP-BF4 was dissolved in AN and used as the electrolyte for supercapacitor. Electrochemical measurements demonstrate that, compared with commercial electrolyte TEMA-BF4/AN, SBP-BF4/AN exhibits high ionic conductivity, lower resistance and improved cycling performance, which is due to its smaller ion size and stable symmetry structure.展开更多
Aerosol samples were collected on board the research vessel Xuelong duringthe Fifteenth Chinese Antarctic Research Expedition (CHINARE XV) in November 1998—April 1999 andthe First Chinese Arctic Research Expedition i...Aerosol samples were collected on board the research vessel Xuelong duringthe Fifteenth Chinese Antarctic Research Expedition (CHINARE XV) in November 1998—April 1999 andthe First Chinese Arctic Research Expedition in July—September 1999.The areas traversed by theexpeditionary cruises include the Arctic Ocean, the western North Pacific Ocean and the easternIndian Ocean, covering 75°N—69°S and 75°E—133°W. Aerosol samples were also taken at theChinese Zhongshan Station in East Antarctica during the CHINARE XV. Analysis of the samples yieldedconcentrations of non-sea-salt sulfate and other soluble chemical species in the marine boundarylayer. The data suggest that the chemical composition of the marine aerosols is influenced by threemajor sources: continental air masses, primary oceanic emissions, and secondary marine aerosolsoriginated from oceanic emissions.The results show that, awing to strong anthropogenic sulfuremissions from the Asian continent, non-sea-salt sulfate concentrations in the Northern Hemisphere(the western North Pacific) marine aerosol are significantly higher than those in the SouthernHemisphere (the eastern Indian Ocean). Aerosol non-sea-salt sulfate concentrations appear to beinversely correlated with aerosol non-sea-salt chloride which shows significantly negative values,indicating the loss of chloride by sea salts, in most aerosol samples. Since gaseous HCl may beinvolved in chemical reactions that deplete atmospheric ozone in the marine boundary layer (MBL),high levels of acidic non-sea-salt-sulfate released by human activities in the low and mid-latitudesof the Northern Hemisphere may become an important potential contributor to the loss of atmosphericozone in the MBL.展开更多
The diffusive boundary layer （DBL） is the zone for matter exchange between surface water and aquatic sediments. To elucidate the influence of DBL on salt release from saline sediments to freshwater, two experiments ...The diffusive boundary layer （DBL） is the zone for matter exchange between surface water and aquatic sediments. To elucidate the influence of DBL on salt release from saline sediments to freshwater, two experiments with or without wind blowing were conducted. According to the experiments, a 3.5 cm DBL is formed above the smoothed sediments at a steady wind field and this thickness is greater than other studies. The observed flux of salt through the DBL is 6% larger than the calculated value from Fick＇ s first law. The results indicate that molecular diffusion is the dominant mechanism for salt transport through the DBL. The presence of DBL suppresses the hydrodynamic enhancement for matter exchange between sediments and overlying water. Therefore, salts in the sediments of a polder reservoir may influence the water quality chronically.展开更多
SrBi4Ti4O15 powder was synthesized by conventional solid state synthesis （ CS ） and molten salt synthesis （ MSS ） . MSS method can synthesize plate-like SrBi4Ti4O15 at lower temperature （900℃） than CS method. P...SrBi4Ti4O15 powder was synthesized by conventional solid state synthesis （ CS ） and molten salt synthesis （ MSS ） . MSS method can synthesize plate-like SrBi4Ti4O15 at lower temperature （900℃） than CS method. Plate-like form becomes more distinct when the synthesis temperature increases. This would help cause the grain orientation of the ceramics after sintering. The sintered samples of MSS had grain orientation at （0,0, 10） plane. The degree of （0,0,10） grain orientation F was 62.1% . Hot pressing made （0,0,10） grain orientation more distinct （ F = 85.7% ）. The microstructures of the sintered samples were detected by SEM. Due to the grain orientation the density of samples fabricated by MSS was lower than that of prepared by CS.展开更多
The spatial variation in the properties of an arrested salt wedge have been investigated,both analytically and in the laboratory.In the laboratory particle image velocimetry and laser induced fluorescence were used to...The spatial variation in the properties of an arrested salt wedge have been investigated,both analytically and in the laboratory.In the laboratory particle image velocimetry and laser induced fluorescence were used to obtain flow velocities and the height of the density interface.An analytical solution for the profile of interface height,in the absence of interfacial instabilities,has been developed from two-layer internal hydraulic theory.The evolution of the velocity profile is predicted using a momentum diffusion equation following a Lagrangian frame of reference along the interface of the salt wedge.The centre of the shear layer is predicted to lie above the density interface,with this offset decreasing in the downstream direction.Our theoretical predictions are in good agreement with our laboratory measurements.展开更多
基金financially supported by the project of investigation and evaluation of potash deposits in the Cretaceous-Tertiary salt basin of the Tarim basin frompotash investigation project of China Geological Survey
文摘Potash is one of the long-term scare deposits in China,and potash prospecting has long been listed as a key brainstorm project for our nation and geological prospecting units.There have been considerable studies in search for potash deposits in the Kuqa depression of the Tarim basin(Jackson et al.,1991;Gemmer et al.,2004;Vendeville,2005;Vendeville and Jackson,1992a,1992b),
文摘Underground salt cavern reservoirs are ideal spaces for energy storage. China is rich in salt rock resources with layered lacustrine sedimentary structures. However, the dissolution mechanism of layered salt rocks remains poorly understood, resulting in significant differences between the actual measurements and the designed indices for the layered salt rock water-soluble cavity-making cycle and the cavity shape. In this work, the dissolution rates of 600 groups of layered salt rocks in China under different conditions were determined experimentally.Thus, the established artificial neural network prediction model was used to assess the effects of the contents of NaCl, Na2 SO4, and CaSO4 in the salt rocks, concentrations, dissolution angles, and flow rates on their dissolution rates by performing ANOVA and F-test. The results provide a theoretical basis for evaluating the dissolution rate of layered salt rocks under different conditions and for the numerical simulation of the layered salt rock water-soluble cavity-making process.
基金Project(51371198)supported by the National Natural Science Foundation of China
文摘A spiro-type quaternary ammonium salt, spiro-(1,1′)-bipyrrolidinium tetrafluoroborate(SBP-BF4) was successfully prepared by an economical and efficient three-step process comprising the cyclization reaction of 1,4-dibromobutane and pyrrolidine, and subsequent ion exchange pathway with KOH followed by neutralization reaction via HBF4 in the system of ethanol solution. 1H NMR, 13 C NMR, FI-IR and XPS analyses showed the structure of SBP-BF4. The as-obtained SBP-BF4 was dissolved in AN and used as the electrolyte for supercapacitor. Electrochemical measurements demonstrate that, compared with commercial electrolyte TEMA-BF4/AN, SBP-BF4/AN exhibits high ionic conductivity, lower resistance and improved cycling performance, which is due to its smaller ion size and stable symmetry structure.
基金supported by the National Natural Science Foundation of China under contract No.40306001the Foundation for the Author of National Excellent Doctoral Dissertation of China under contract No.200354)from the Ministry of Education and the Chinese Academy of Sciences+1 种基金supported by the Wang kuancheng Foundation(the Chinese Academy of Sciences)Fieldwork was sup-ported by the Chinese Arctic and Antarctic Adminis-tration(CAAA),the 15 th Chinese Antarctic Research Expedition and the First and Second Chinese Arctic Research Expedition.
文摘Aerosol samples were collected on board the research vessel Xuelong duringthe Fifteenth Chinese Antarctic Research Expedition (CHINARE XV) in November 1998—April 1999 andthe First Chinese Arctic Research Expedition in July—September 1999.The areas traversed by theexpeditionary cruises include the Arctic Ocean, the western North Pacific Ocean and the easternIndian Ocean, covering 75°N—69°S and 75°E—133°W. Aerosol samples were also taken at theChinese Zhongshan Station in East Antarctica during the CHINARE XV. Analysis of the samples yieldedconcentrations of non-sea-salt sulfate and other soluble chemical species in the marine boundarylayer. The data suggest that the chemical composition of the marine aerosols is influenced by threemajor sources: continental air masses, primary oceanic emissions, and secondary marine aerosolsoriginated from oceanic emissions.The results show that, awing to strong anthropogenic sulfuremissions from the Asian continent, non-sea-salt sulfate concentrations in the Northern Hemisphere(the western North Pacific) marine aerosol are significantly higher than those in the SouthernHemisphere (the eastern Indian Ocean). Aerosol non-sea-salt sulfate concentrations appear to beinversely correlated with aerosol non-sea-salt chloride which shows significantly negative values,indicating the loss of chloride by sea salts, in most aerosol samples. Since gaseous HCl may beinvolved in chemical reactions that deplete atmospheric ozone in the marine boundary layer (MBL),high levels of acidic non-sea-salt-sulfate released by human activities in the low and mid-latitudesof the Northern Hemisphere may become an important potential contributor to the loss of atmosphericozone in the MBL.
基金The National Science Foundation of China under contract No.40572142the Doctoral Foundation of the Ministry of Education of China under contract No.20040423016.
文摘The diffusive boundary layer （DBL） is the zone for matter exchange between surface water and aquatic sediments. To elucidate the influence of DBL on salt release from saline sediments to freshwater, two experiments with or without wind blowing were conducted. According to the experiments, a 3.5 cm DBL is formed above the smoothed sediments at a steady wind field and this thickness is greater than other studies. The observed flux of salt through the DBL is 6% larger than the calculated value from Fick＇ s first law. The results indicate that molecular diffusion is the dominant mechanism for salt transport through the DBL. The presence of DBL suppresses the hydrodynamic enhancement for matter exchange between sediments and overlying water. Therefore, salts in the sediments of a polder reservoir may influence the water quality chronically.
文摘SrBi4Ti4O15 powder was synthesized by conventional solid state synthesis （ CS ） and molten salt synthesis （ MSS ） . MSS method can synthesize plate-like SrBi4Ti4O15 at lower temperature （900℃） than CS method. Plate-like form becomes more distinct when the synthesis temperature increases. This would help cause the grain orientation of the ceramics after sintering. The sintered samples of MSS had grain orientation at （0,0, 10） plane. The degree of （0,0,10） grain orientation F was 62.1% . Hot pressing made （0,0,10） grain orientation more distinct （ F = 85.7% ）. The microstructures of the sintered samples were detected by SEM. Due to the grain orientation the density of samples fabricated by MSS was lower than that of prepared by CS.
基金supported by the Natural Sciences and the Engineering Research Council(NSERC)of Canada
文摘The spatial variation in the properties of an arrested salt wedge have been investigated,both analytically and in the laboratory.In the laboratory particle image velocimetry and laser induced fluorescence were used to obtain flow velocities and the height of the density interface.An analytical solution for the profile of interface height,in the absence of interfacial instabilities,has been developed from two-layer internal hydraulic theory.The evolution of the velocity profile is predicted using a momentum diffusion equation following a Lagrangian frame of reference along the interface of the salt wedge.The centre of the shear layer is predicted to lie above the density interface,with this offset decreasing in the downstream direction.Our theoretical predictions are in good agreement with our laboratory measurements.
