Almost half of the oceanic water columns exhibit double-diffusion. The importance of double-diffusion in global oceans’ salt and heat fluxes, water-mass formation and mixing, and circulation is increasingly recognize...Almost half of the oceanic water columns exhibit double-diffusion. The importance of double-diffusion in global oceans’ salt and heat fluxes, water-mass formation and mixing, and circulation is increasingly recognized. However, such an important physical process in the ocean has not been well studied. One of the reasons is the difficulty of parameterizing and quantifying the processes. The paper presented here attempts to quantify the double-diffusive fluxes of salt and heat in the ocean. Previous qualitative analysis by applying the water-mass Turner angle, mTu, to the North Pacific Intermediate Water (NPIW) layer showed a favorable condition for salt-fingering in the upper NPIW due to the overlying warm/salty water above the cold/fresh NPIW core, and a doubly-stable condition in the lower NPIW where potential temperature decreases with depth while salinity increases, inducing double stratification with respect to both potential temperature and salinity. The present study gives a quantitative estimate of double-diffusive fluxes of salt and heat contributed by salt-fingering in the upper NPIW layer.展开更多
Underground brine is an unusual water resource that contains abundant mineral resources. It is distributed widely in the Qaidam Basin, western China, a hyperarid inland basin located in the northern Tibetan Plateau. P...Underground brine is an unusual water resource that contains abundant mineral resources. It is distributed widely in the Qaidam Basin, western China, a hyperarid inland basin located in the northern Tibetan Plateau. Pores in the brine storage medium act as storage space and transmission channels of underground brine. Therefore, the porosity of brine storage medium determines its ability to store brine. In this study, Mahai Salt Lake was used as the research area as a modern saline lake located in the north area of the Qaidam Basin. A total of 100 porosity samples were collected from eight sampling points in two profiles of the research area at sampling depths of 1.30–314.78 m. The porosity distribution characteristics and influencing factors in brine storage medium were analysed according to the measured porosity data. Based on analysis of the pore structure characteristics, the brine storage medium contains intercrystalline pores, unlike conventional freshwater storage mediums. Moreover, the primary salt rock is susceptible to dissolution by lighter brine, facilitating the formation of secondary porosity. Due to the formation of secondary pores, a porosity greater than 20% remains even at buried depths greater than 100 m. Based on the geological statistical analysis, due to the geographic location, salt formation time, and depositional environment, the porosity values of Mahai Salt Lake do not exhibit a wider distribution, but also show more extreme values than a nearby salt lake. Based on the porosity characteristics by depth, due to the presence of secondary pores, flooding, stratigraphic static pressure, and other factors, porosity shows fluctuations with increasing depth.展开更多
The reactivity of Na2B4O7·5HaO and Na2B4O7 in non-aqueous HCl-CH3OH solvent system was investigated. The effects of H2O, CH3OH/B mole ratio and reaction time on the reaction at room temperature were examined. Exp...The reactivity of Na2B4O7·5HaO and Na2B4O7 in non-aqueous HCl-CH3OH solvent system was investigated. The effects of H2O, CH3OH/B mole ratio and reaction time on the reaction at room temperature were examined. Experimental results show that when Na2B4O7·5H2O and Na2B4O7 are the reactants, the dissolved B203 contents are observed to be 98.2% and 99%, respectively, in 5min at the CH3OH/B mole ratio of 4. The decrease of water in the reaction medium was observed to increase the crystallization of NaCI in the order of Na2B4O7〉Na2B4O7·5H2O It was also observed that the boron solution obtained after the reaction could be hydrolyzed by the addition of H3BO3. The results show that HCl-CH3OH system is a more effective solvent compared to H2SO4-CH3OH both in the reactivity and the shortened reaction time.展开更多
基金a result of my short visit to the Physical Oceanography Laboratory of Ocean University of ChinaQingdao with support from the Foundation for Open Projects of the Key Lab.of Physical Oceanography,the Ministry of Education,China(No.200401).
文摘Almost half of the oceanic water columns exhibit double-diffusion. The importance of double-diffusion in global oceans’ salt and heat fluxes, water-mass formation and mixing, and circulation is increasingly recognized. However, such an important physical process in the ocean has not been well studied. One of the reasons is the difficulty of parameterizing and quantifying the processes. The paper presented here attempts to quantify the double-diffusive fluxes of salt and heat in the ocean. Previous qualitative analysis by applying the water-mass Turner angle, mTu, to the North Pacific Intermediate Water (NPIW) layer showed a favorable condition for salt-fingering in the upper NPIW due to the overlying warm/salty water above the cold/fresh NPIW core, and a doubly-stable condition in the lower NPIW where potential temperature decreases with depth while salinity increases, inducing double stratification with respect to both potential temperature and salinity. The present study gives a quantitative estimate of double-diffusive fluxes of salt and heat contributed by salt-fingering in the upper NPIW layer.
基金Under the auspices of The National Natural Science Fundation of China(No.41572216,41672243)The Water Resources Project of Jilin Province(No.0773-1441GNJL00390)+1 种基金The Natural Science Fundation of Jilin Province(No.20140101164JC)Science and Technology Support Program of Qinghai Province(No.2012-G-154A)
文摘Underground brine is an unusual water resource that contains abundant mineral resources. It is distributed widely in the Qaidam Basin, western China, a hyperarid inland basin located in the northern Tibetan Plateau. Pores in the brine storage medium act as storage space and transmission channels of underground brine. Therefore, the porosity of brine storage medium determines its ability to store brine. In this study, Mahai Salt Lake was used as the research area as a modern saline lake located in the north area of the Qaidam Basin. A total of 100 porosity samples were collected from eight sampling points in two profiles of the research area at sampling depths of 1.30–314.78 m. The porosity distribution characteristics and influencing factors in brine storage medium were analysed according to the measured porosity data. Based on analysis of the pore structure characteristics, the brine storage medium contains intercrystalline pores, unlike conventional freshwater storage mediums. Moreover, the primary salt rock is susceptible to dissolution by lighter brine, facilitating the formation of secondary porosity. Due to the formation of secondary pores, a porosity greater than 20% remains even at buried depths greater than 100 m. Based on the geological statistical analysis, due to the geographic location, salt formation time, and depositional environment, the porosity values of Mahai Salt Lake do not exhibit a wider distribution, but also show more extreme values than a nearby salt lake. Based on the porosity characteristics by depth, due to the presence of secondary pores, flooding, stratigraphic static pressure, and other factors, porosity shows fluctuations with increasing depth.
文摘The reactivity of Na2B4O7·5HaO and Na2B4O7 in non-aqueous HCl-CH3OH solvent system was investigated. The effects of H2O, CH3OH/B mole ratio and reaction time on the reaction at room temperature were examined. Experimental results show that when Na2B4O7·5H2O and Na2B4O7 are the reactants, the dissolved B203 contents are observed to be 98.2% and 99%, respectively, in 5min at the CH3OH/B mole ratio of 4. The decrease of water in the reaction medium was observed to increase the crystallization of NaCI in the order of Na2B4O7〉Na2B4O7·5H2O It was also observed that the boron solution obtained after the reaction could be hydrolyzed by the addition of H3BO3. The results show that HCl-CH3OH system is a more effective solvent compared to H2SO4-CH3OH both in the reactivity and the shortened reaction time.
