Based on the hazard development mechanism, a water solution area is closely related to the supporting effect of pressure-bearing water, the relaxing and collapsing effect of orebody interlayer, the collapsing effect o...Based on the hazard development mechanism, a water solution area is closely related to the supporting effect of pressure-bearing water, the relaxing and collapsing effect of orebody interlayer, the collapsing effect of thawless material in orebody, filling effect caused by cubical expansibility of hydrate crystallization and uplifting effect of hard rock layer over cranny belt. The movement and deformation of ground surface caused by underground water solution mining is believed to be much weaker than that caused by well lane mining, which can be predicted by the stochastic medium theory method. On the basis of analysis on the engineering practice of water solution mining, its corresponding parameters can be obtained from the in-site data of the belt water and sand filling mining in engineering analog approach.展开更多
The annual allocation, inter-annual variation and relation of water diversion and recession are analyzed in Ningxia reach of the Yellow River main stream from 1999 to 2012. Water consumption in Ningxia reach was calcu...The annual allocation, inter-annual variation and relation of water diversion and recession are analyzed in Ningxia reach of the Yellow River main stream from 1999 to 2012. Water consumption in Ningxia reach was calculated by water diversion-recession method and water balance method. The average value of water diversion-recession method is 3.264 billion m3 and annual varia-tion is relatively steady. The result of water balance method is 3.937 billion m3 and annual variation is obvious. It is suggested that strengthen verification of entrances and monitoring of water diversion and recession.展开更多
Recently,research on hydrogel materials with a porous structure and superior water absorption capabilities significantly grown.However,the hydrogel under gravity-driven separation conditions often exhibit an unstable ...Recently,research on hydrogel materials with a porous structure and superior water absorption capabilities significantly grown.However,the hydrogel under gravity-driven separation conditions often exhibit an unstable pore structure,poor mechanical properties,and limited functionality.To this end,this work presents a novel approach that combines a macro-micro double bionic strategy with a triple crosslinking method to develop a multifunctional alginate composite hydrogel filter(2%-SA-κCG-PVA-Ca^(2+),2%-SKP-Ca^(2+)for short)with a stable pore structure and superior mechanical properties,which possessed an umbrella-shaped structure resembling that of jellyfish.The 2%-SKPCa^(2+)filter was synthesized using polyvinyl alcohol(PVA)as a stable structure-directing agent,and sodium alginate(SA)andκ-carrageenan(κ-CG)as polymer hydrogels.The distinctive umbrellashaped hydrogel of 2%-SKP-Ca^(2+)filter,formed through the triple crosslinking method,overcomes the limitations of unstable pore structure and poor durability seen in hydrogels prepared by traditional crosslinking methods.Furthermore,the utilization of the 2%-SKP-Ca^(2+)filter in water treatment demonstrates its good selective permeability,excellent resistance to fouling,and extended longevity,which enables it to simultaneously achieve the multifunctional water purification and the coating of multi-substrate anti-fouling coatings.Therefore,not only does this research provide an efficient,multifunctional,highly pollution-resistant preparation method for designing a new filter,but it also confirms the application prospect of the macro-micro dual bionic strategy developed in this study in complex water treatment.展开更多
Nowadays there are some chronic serious environmental problems, such as eutrophication, blue tide and so on, in a complicated coastal zone or a semi-enclosed bay, because the water exchanges between an inner bay and a...Nowadays there are some chronic serious environmental problems, such as eutrophication, blue tide and so on, in a complicated coastal zone or a semi-enclosed bay, because the water exchanges between an inner bay and an outer sea is weak compared with the supply of contaminant. Under this situation, a method to improve the water quality by 3-dimensional small unsymmetrical structures has been proposed by Komatsu et al. In this paper, several numerical simulations of the tidal current and concentration for various arrangements of bottom roughness in a semi-enclosed model bay are carfled out with a depth-averaged 2-D numerical model. The model is solved by the hybrid finite analytic method with nonstaggered grid. And the SIMPLES algorithm with Rhie and Chow＇ s momentum interpolation technique is used for the simulation. The effect of Komatsu＇ s method for water purification is examined by numerical simulation. The result of numerical experiment indicates that it is possible to generate a new tidal residual current and to activate a tidal exchange by bottom roughness arrangement only.展开更多
To explore the water table and water inflow after tunnel excavation in a vertically stratified phreatic aquifer,approximate analytical solutions for the steady-state water table and water inflow of a drained tunnel in...To explore the water table and water inflow after tunnel excavation in a vertically stratified phreatic aquifer,approximate analytical solutions for the steady-state water table and water inflow of a drained tunnel in a vertically stratified phreatic aquifer were obtained based on the Dupuit assumptions and the integral method.By comparing the approximate analytical solutions with numerical solutions,it was found that the relative error of the approximate analytical solution for the water table elevation is less than 10%,and the relative error of the approximate analytical solution for the water inflow is approximately 25%.The sources of the above errors are as follows:(1)At the lateral boundary of water replenishment,the water surface should be tangent to the horizontal line,but the water surface for the approximate analytical solutions has a gradient.(2)At the vertical boundaries near the tunnel,the total head is variable,but the total head for the approximate analytical solutions is assumed to be constant.(3)The Dupuit assumptions are applied in the flow domain near the tunnel.Although the relative errors of the approximate analytical solutions for the water table elevation and water inflow are evident,the lowered water table is reflected in the approximate analytical solutions.展开更多
基金Project(40404001) supported by the National Natural Science Foundation of China
文摘Based on the hazard development mechanism, a water solution area is closely related to the supporting effect of pressure-bearing water, the relaxing and collapsing effect of orebody interlayer, the collapsing effect of thawless material in orebody, filling effect caused by cubical expansibility of hydrate crystallization and uplifting effect of hard rock layer over cranny belt. The movement and deformation of ground surface caused by underground water solution mining is believed to be much weaker than that caused by well lane mining, which can be predicted by the stochastic medium theory method. On the basis of analysis on the engineering practice of water solution mining, its corresponding parameters can be obtained from the in-site data of the belt water and sand filling mining in engineering analog approach.
文摘The annual allocation, inter-annual variation and relation of water diversion and recession are analyzed in Ningxia reach of the Yellow River main stream from 1999 to 2012. Water consumption in Ningxia reach was calculated by water diversion-recession method and water balance method. The average value of water diversion-recession method is 3.264 billion m3 and annual varia-tion is relatively steady. The result of water balance method is 3.937 billion m3 and annual variation is obvious. It is suggested that strengthen verification of entrances and monitoring of water diversion and recession.
基金received generous support from multiple sources,including the Zhejiang Provincial Natural Science Foundation of China(No.LY23D060004)the Science and Technology Planning Project of Zhoushan,China(Nos.2022C41005 and 2019C21007)the National Natural Science Foundation of China(No.51606168).
文摘Recently,research on hydrogel materials with a porous structure and superior water absorption capabilities significantly grown.However,the hydrogel under gravity-driven separation conditions often exhibit an unstable pore structure,poor mechanical properties,and limited functionality.To this end,this work presents a novel approach that combines a macro-micro double bionic strategy with a triple crosslinking method to develop a multifunctional alginate composite hydrogel filter(2%-SA-κCG-PVA-Ca^(2+),2%-SKP-Ca^(2+)for short)with a stable pore structure and superior mechanical properties,which possessed an umbrella-shaped structure resembling that of jellyfish.The 2%-SKPCa^(2+)filter was synthesized using polyvinyl alcohol(PVA)as a stable structure-directing agent,and sodium alginate(SA)andκ-carrageenan(κ-CG)as polymer hydrogels.The distinctive umbrellashaped hydrogel of 2%-SKP-Ca^(2+)filter,formed through the triple crosslinking method,overcomes the limitations of unstable pore structure and poor durability seen in hydrogels prepared by traditional crosslinking methods.Furthermore,the utilization of the 2%-SKP-Ca^(2+)filter in water treatment demonstrates its good selective permeability,excellent resistance to fouling,and extended longevity,which enables it to simultaneously achieve the multifunctional water purification and the coating of multi-substrate anti-fouling coatings.Therefore,not only does this research provide an efficient,multifunctional,highly pollution-resistant preparation method for designing a new filter,but it also confirms the application prospect of the macro-micro dual bionic strategy developed in this study in complex water treatment.
基金This work was supported bythe National Science Fundfor Distinguished Young Scholars of Ministry of Eduction,Chi-na
文摘Nowadays there are some chronic serious environmental problems, such as eutrophication, blue tide and so on, in a complicated coastal zone or a semi-enclosed bay, because the water exchanges between an inner bay and an outer sea is weak compared with the supply of contaminant. Under this situation, a method to improve the water quality by 3-dimensional small unsymmetrical structures has been proposed by Komatsu et al. In this paper, several numerical simulations of the tidal current and concentration for various arrangements of bottom roughness in a semi-enclosed model bay are carfled out with a depth-averaged 2-D numerical model. The model is solved by the hybrid finite analytic method with nonstaggered grid. And the SIMPLES algorithm with Rhie and Chow＇ s momentum interpolation technique is used for the simulation. The effect of Komatsu＇ s method for water purification is examined by numerical simulation. The result of numerical experiment indicates that it is possible to generate a new tidal residual current and to activate a tidal exchange by bottom roughness arrangement only.
基金supported by the High Speed Railway and Natural Science United Foundation of China(No.U1734205)the Fundamental Research Funds for the Central Universities of China(No.2682021CG002)+1 种基金the National Natural Science Foundation of China(No.51808459)the China State Railway Group Co.,Ltd.Science and Technology Research and Development Program Systematic Major Project(No.P2019G040)。
文摘To explore the water table and water inflow after tunnel excavation in a vertically stratified phreatic aquifer,approximate analytical solutions for the steady-state water table and water inflow of a drained tunnel in a vertically stratified phreatic aquifer were obtained based on the Dupuit assumptions and the integral method.By comparing the approximate analytical solutions with numerical solutions,it was found that the relative error of the approximate analytical solution for the water table elevation is less than 10%,and the relative error of the approximate analytical solution for the water inflow is approximately 25%.The sources of the above errors are as follows:(1)At the lateral boundary of water replenishment,the water surface should be tangent to the horizontal line,but the water surface for the approximate analytical solutions has a gradient.(2)At the vertical boundaries near the tunnel,the total head is variable,but the total head for the approximate analytical solutions is assumed to be constant.(3)The Dupuit assumptions are applied in the flow domain near the tunnel.Although the relative errors of the approximate analytical solutions for the water table elevation and water inflow are evident,the lowered water table is reflected in the approximate analytical solutions.
