In this paper we study the interaction of strong and weak singularities for hyperbolic system of conservation laws in multidimensional space. Under the assumption of transversal intersect of the shock front with the b...In this paper we study the interaction of strong and weak singularities for hyperbolic system of conservation laws in multidimensional space. Under the assumption of transversal intersect of the shock front with the bicharacteristics bearing weak singularities we proved a theorem on regularity propagation across the shock front.展开更多
Given the important role of iodine resources in chemical industry application and the scarcity of geogenic iodine resources,sustainable access to iodine resources has become increasingly crucial.Seawater is the larges...Given the important role of iodine resources in chemical industry application and the scarcity of geogenic iodine resources,sustainable access to iodine resources has become increasingly crucial.Seawater is the largest iodine reservoir on Earth,but efficient chemical methods for recovering iodine from seawater are still lacking.Concurrently,the remediation of radioactive iodine pollution in seawater,caused by nuclear accident,remains a great challenge.Supramolecular organic frameworks(SOFs)are considered promising candidates for the recovery of aqueous iodine.However,currently available SOF adsorbents lack sufficient iodine storage space,resulting in low iodine adsorption capacity.Herein,we developed a 3-dimensional(3D)SOF,named SOF-HTNI,via the self-assembly of 2 adjustable compounds,including the internal amine bond-rotatable 5-(bis(4-carboxybenzyl)amino)isophthalic acid(HT)and the configuration-transformable 4,4′-[1,4-phenylenedi-(1E)-2,1-ethenediyl]bis-pyridine(NI),for highly efficient iodine recovery from seawater.Due to the rigid support and the formation of hydrogen bonds and π-π stacking interactions between the compounds,interconnected 1D channels and 2D interlayer nanospaces are constructed within SOF-HTNI,providing abundant flexible spaces for iodine storage.By combining the charge interaction of the amine and pyridyl groups from the compounds with the binding ability of aromatic rings,SOF-HTNI achieves impressive iodine adsorption capacities of 436.56 mg g^(-1) to iodide and 5.03 g g^(-1) to triiodide.Notably,SOF-HTNI realizes a high iodine capture capacity of 46 mg g^(-1) in natural seawater,40 times greater than that of seaweed.These findings make SOF-HTNI a highly promising material for iodine pollution treatment and iodine resource recovery in seawater.展开更多
A scientific and rational evaluation on road-region ecosystem stability is the premise to properly deal with the relationship between highway constructing and ecological environment protecting to a sustainable develop...A scientific and rational evaluation on road-region ecosystem stability is the premise to properly deal with the relationship between highway constructing and ecological environment protecting to a sustainable development. Based on the connotative meaning and the procedure of evaluation on road-region ecosystem stability, this paper studied the principles and the method on determining the evaluation index system on road-region ecosystem stability. It put forward an index system for assessing road-region ecosystem stability as a reference. On the basis of detailed analyze of the multidimensional space of road-region ecosystem, a new multi-objective comprehensive evaluation method for road-region ecosystem stability is presented and a calculation tormula for multi-objective comprehensive level of road-region ecosystem stability. This method was used to evaluate road-region ecosystem stability of Lin-Chang highway. This method possessed definite theoretical value and reliability in practice.展开更多
文摘In this paper we study the interaction of strong and weak singularities for hyperbolic system of conservation laws in multidimensional space. Under the assumption of transversal intersect of the shock front with the bicharacteristics bearing weak singularities we proved a theorem on regularity propagation across the shock front.
基金supported by the Hainan Provincial Natural Science Foundation of China(624MS034)the specific research fund of the Innovation Platform for Academicians of Hainan Province(YSPTZX202214 and YSPTZX202316)+3 种基金the National Natural Science Foundation of China(U2167220,22327807,and U23A20104)the Hainan Province Science and Technology Special Fund(ZDYF2024SHFZ066)the National Key Research and Development Program of China(2023YFC2809000)the Innovation Fund for Scientific and Technological Personnel of Hainan Province(KJRC2023B01).
文摘Given the important role of iodine resources in chemical industry application and the scarcity of geogenic iodine resources,sustainable access to iodine resources has become increasingly crucial.Seawater is the largest iodine reservoir on Earth,but efficient chemical methods for recovering iodine from seawater are still lacking.Concurrently,the remediation of radioactive iodine pollution in seawater,caused by nuclear accident,remains a great challenge.Supramolecular organic frameworks(SOFs)are considered promising candidates for the recovery of aqueous iodine.However,currently available SOF adsorbents lack sufficient iodine storage space,resulting in low iodine adsorption capacity.Herein,we developed a 3-dimensional(3D)SOF,named SOF-HTNI,via the self-assembly of 2 adjustable compounds,including the internal amine bond-rotatable 5-(bis(4-carboxybenzyl)amino)isophthalic acid(HT)and the configuration-transformable 4,4′-[1,4-phenylenedi-(1E)-2,1-ethenediyl]bis-pyridine(NI),for highly efficient iodine recovery from seawater.Due to the rigid support and the formation of hydrogen bonds and π-π stacking interactions between the compounds,interconnected 1D channels and 2D interlayer nanospaces are constructed within SOF-HTNI,providing abundant flexible spaces for iodine storage.By combining the charge interaction of the amine and pyridyl groups from the compounds with the binding ability of aromatic rings,SOF-HTNI achieves impressive iodine adsorption capacities of 436.56 mg g^(-1) to iodide and 5.03 g g^(-1) to triiodide.Notably,SOF-HTNI realizes a high iodine capture capacity of 46 mg g^(-1) in natural seawater,40 times greater than that of seaweed.These findings make SOF-HTNI a highly promising material for iodine pollution treatment and iodine resource recovery in seawater.
文摘A scientific and rational evaluation on road-region ecosystem stability is the premise to properly deal with the relationship between highway constructing and ecological environment protecting to a sustainable development. Based on the connotative meaning and the procedure of evaluation on road-region ecosystem stability, this paper studied the principles and the method on determining the evaluation index system on road-region ecosystem stability. It put forward an index system for assessing road-region ecosystem stability as a reference. On the basis of detailed analyze of the multidimensional space of road-region ecosystem, a new multi-objective comprehensive evaluation method for road-region ecosystem stability is presented and a calculation tormula for multi-objective comprehensive level of road-region ecosystem stability. This method was used to evaluate road-region ecosystem stability of Lin-Chang highway. This method possessed definite theoretical value and reliability in practice.
