Metal oxides as support for constructing precious metal single-atom catalysts hold great promise for a wide range of industrial applications,but achieving a high-loading of thermally stable metal single atoms on such ...Metal oxides as support for constructing precious metal single-atom catalysts hold great promise for a wide range of industrial applications,but achieving a high-loading of thermally stable metal single atoms on such supports has been challenging.Herein,we report an innovative strategy for the fabrication of high-density single-atoms(Rh,Ru,Pd)catalysts on CaAl-layered double hydroxides(CaAl-LDH)via isomorphous substitution.The Rh species have occupied Ca^(2+)vacancies within CaAl-LDH laminate by ion-exchange,facilitating a substantial loading of isolated Rh single-atoms.Such catalysts displayed superior performance in the selective hydrogenation to quinoline,pivotal for liquid organic hydrogen storage,and the universality for the hydrogenation of N-heterocyclic aromatic hydrocarbons was also verified.Combining the experimental results and density functional theory calculations,the pathway of quinoline hydrogenation over Rh1CaAl-LDH was proposed.This synthetic strategy marks a significant advancement in the field of single-atom catalysts,expanding their horizons in green chemical processes.展开更多
We analyze existence and uniqueness of solutions for perturbations of a Jensen functional inequality in several variables.Applications in connection with asymptotic behaviors of isomorphisms,derivations and n-Jordan d...We analyze existence and uniqueness of solutions for perturbations of a Jensen functional inequality in several variables.Applications in connection with asymptotic behaviors of isomorphisms,derivations and n-Jordan derivations on Banach algebras are also provided.The results of this paper correct and improve the main results of[12,16,22,23]and improve the corresponding results in[2,9,27],but under weaker assumptions.展开更多
In this article, we prove the Hyers-Ulam-Rassias stability of the following Cauchy-Jensen functional inequality：‖f （x） ＋ f （y） ＋ 2f （z） ＋ 2f （w）‖ ≤‖ 2f x ＋ y2 ＋ z ＋ w ‖（0.1）This is applied to inv...In this article, we prove the Hyers-Ulam-Rassias stability of the following Cauchy-Jensen functional inequality：‖f （x） ＋ f （y） ＋ 2f （z） ＋ 2f （w）‖ ≤‖ 2f x ＋ y2 ＋ z ＋ w ‖（0.1）This is applied to investigate isomorphisms between C＊-algebras, Lie C＊-algebras and JC＊-algebras, and derivations on C＊-algebras, Lie C＊-algebras and JC＊-algebras, associated with the Cauchy-Jensen functional equation 2f （x ＋ y/2 ＋ z ＋ w） = f（x） ＋ f（y） ＋ 2f（z） ＋ 2f（w）.展开更多
Evolutionary computation techniques have mostly been used to solve various optimization problems, and it is well known that graph isomorphism problem （GIP） is a nondeterministic polynomial problem. A simulated annea...Evolutionary computation techniques have mostly been used to solve various optimization problems, and it is well known that graph isomorphism problem （GIP） is a nondeterministic polynomial problem. A simulated annealing （SA） algorithm for detecting graph isomorphism is proposed, and the proposed SA algorithm is well suited to deal with random graphs with large size. To verify the validity of the proposed SA algorithm, simulations are performed on three pairs of small graphs and four pairs of large random graphs with edge densities 0.5, 0.1, and 0.01, respectively. The simulation results show that the proposed SA algorithm can detect graph isomorphism with a high probability.展开更多
Most of the phosphorite deposits in the world contain isomorphism rare earths （RE） which are considerably difficult to be leached into solution in the wet phos- phoric acid process. In this work, a systematic study ...Most of the phosphorite deposits in the world contain isomorphism rare earths （RE） which are considerably difficult to be leached into solution in the wet phos- phoric acid process. In this work, a systematic study of leaching RE using sulfuric acid, phosphoric acid, mixed acid and two-step leaching of phosphoric acid and sulfuric acid was performed. The aims are to illuminate the main factors that inhibit RE leaching and to provide insights into the further enrichment of RE in the wet phosphoric acid solution. The results indicate that H2SO4 is not an effective acid for leaching isomorphism RE from phosphorite ore. The low RE leaching efficiency attributes to the RE cocrystallized and encapsulated by phosphogypsum （PG） as well as the precipitation of RE by RE sulfates or phosphates. High concentration of H3PO4 can enhance the dissolution and diffusion of RE ions. Hence, the optimized leaching mode of improving RE leaching efficiency is to adequately dissolve phosphorite ores in high concentration of H3PO4 solution and then add H2SO4 to crystallize PG. The effect of corystallization or encapsulation of PG on RE can be decreased due to the crystallizing mode of PG in the bulk solution instead of on the interface of solid reactants. RE leaching efficiency can be high up to 65% by the optimized leaching mode.展开更多
Basing on the papers from [1] to [4], this paper gives some further research,mainly solves the following problems:(1) It proved that several theorems of subgroup which have been raised to the hypergroup are still true...Basing on the papers from [1] to [4], this paper gives some further research,mainly solves the following problems:(1) It proved that several theorems of subgroup which have been raised to the hypergroup are still true.(2) It proved that the isomorphous relationship of the bottomgroups which guid to the hypergroup can still keep such relationship.(3) It proved that the basic isomorphous Theorem and the homogenous Theorem of the bottomgroup which raise to the hypergroup are still true.(4) It point out that when the isomorphous bottomgroups have been raised to the hypergroup,the conditions which form the isomorphism should be lessened.展开更多
This study undertakes a systematic examination of characteristics of the spatio-temporal evolution of industrial economies in Central Asia from the perspectives of industrial scale,structural rationality,industrial co...This study undertakes a systematic examination of characteristics of the spatio-temporal evolution of industrial economies in Central Asia from the perspectives of industrial scale,structural rationality,industrial competitiveness,and industrial isomorphism.The results show that industrial structures in Central Asian countries are becoming increasingly advanced,with certain differences among them in the characteristics of this evolution.Kazakhstan has long had a tertiary-secondary-primary industrial pattern,and productive services have played an increasingly prominent role in the development of its tertiary industry.The transformation of the industrial structure in Uzbekistan,from a secondary-tertiary-primary pattern at its independence from the Soviet Union to a tertiary-secondary-primary pattern,is apparent.Tajikistan's industrial structure has also changed significantly in recent times.Its secondary industries shrunk while tertiary industries developed rapidly.In Kyrgyzstan,the ratios of secondary and tertiary industries to total industrial output have fluctuated significantly while considerable progress has been made in the service sector.The industrial structure of Turkmenistan is significantly lower than the other countries,and Turkmenistan is the only country in the Central Asian region which still shows a tertiary-secondary-primary industrial pattern.The feasibility and competitiveness of the industrial structures of these five Central Asian countries have different characteristics.Kazakhstan has structural advantages but lags in competitiveness,Uzbekistan is driven by both structural and competitive advantages,Tajikistan enjoys structural advantages while Kyrgyzstan lags behind in competitiveness,and Turkmenistan has a competitiveness-driven economy.Furthermore,values of the similar coefficient index of the three industrial structures in these countries were mostly above 0.95,the coefficients of the secondary industrial subdivisions in some countries were below 0.85,and those of tertiary industrial subdivisions among most countries were above 0.89,indicating considerable similarities in industrial structure among them.These findings are important in the context of establishing an effective industrial development strategy for the Silk Road Economic Belt,improving international cooperation,and upgrading industrial structures to achieve economic prosperity.展开更多
If T is an isomorphism of （c0） into C（Ω） （where Ω is a sequentially compact and paracompact space, or a compact metric space in particular）, which satisfies the condition ｜｜T｜｜·｜｜T^-1｜｜ ≤ 1 ＋ε ...If T is an isomorphism of （c0） into C（Ω） （where Ω is a sequentially compact and paracompact space, or a compact metric space in particular）, which satisfies the condition ｜｜T｜｜·｜｜T^-1｜｜ ≤ 1 ＋ε for some ε ∈ （0,1/5）, then T/｜｜T｜｜ is close to an isometry with an error less than 9ε. The proof of this article is simple without using the dual space or adjoint operator.展开更多
Isomorphism detection is fundamental to the synthesis and innovative design of kinematic chains(KCs).The detection can be performed accurately by using the similarity of KCs.However,there are very few works on isomorp...Isomorphism detection is fundamental to the synthesis and innovative design of kinematic chains(KCs).The detection can be performed accurately by using the similarity of KCs.However,there are very few works on isomorphism detection based on the properties of similar vertices.In this paper,an ameliorated multi-order adjacent vertex assignment sequence(AMAVS)method is proposed to seek out similar vertices and identify the isomorphism of the planar KCs.First,the specific definition of AMAVS is described.Through the calculation of the AMAVS,the adjacent vertex value sequence reflecting the uniqueness of the topology features is established.Based on the value sequence,all possible similar vertices,corresponding relations,and isomorphism discrimination can be realized.By checking the topological graph of KCs with a different number of links,the effectiveness and efficiency of the proposed method are verified.Finally,the method is employed to implement the similar vertices and isomorphism detection of all the 9-link 2-D0F(degree of freedom)planar KCs.展开更多
In this paper we study the isomorphisms of two ＊-bisimple type A ω2-semigroups such that D^＊ = ^~D） and obtain a criterion for isomorphisms of two such semigroups.
A novel framework for parallel subgraph isomorphism on GPUs is proposed, named GPUSI, which consists of GPU region exploration and GPU subgraph matching. The GPUSI iteratively enumerates subgraph instances and solves ...A novel framework for parallel subgraph isomorphism on GPUs is proposed, named GPUSI, which consists of GPU region exploration and GPU subgraph matching. The GPUSI iteratively enumerates subgraph instances and solves the subgraph isomorphism in a divide-and-conquer fashion. The framework completely relies on the graph traversal, and avoids the explicit join operation. Moreover, in order to improve its performance, a task-queue based method and the virtual-CSR graph structure are used to balance the workload among warps, and warp-centric programming model is used to balance the workload among threads in a warp. The prototype of GPUSI is implemented, and comprehensive experiments of various graph isomorphism operations are carried on diverse large graphs. The experiments clearly demonstrate that GPUSI has good scalability and can achieve speed-up of 1.4–2.6 compared to the state-of-the-art solutions.展开更多
The adjacent matrix method for identifying isomorphism to planar kinematic chain with multiple joints and higher pairs is presented. The topological invariants of the planar kinematic chain can be calculated and compa...The adjacent matrix method for identifying isomorphism to planar kinematic chain with multiple joints and higher pairs is presented. The topological invariants of the planar kinematic chain can be calculated and compared by adjacent matrix. The quantity of calculation can be reduced effectively using the several divisions of bars and the reconfiguration of the adjacent matrix. As two structural characteristics of adjacent matrix, the number of division and division code are presented. It can be identified that two kinematic chains are isomorphic or not by comparing the structural characteristics of their adjacent matrixes using a method called matching row-to-row. This method may be applied to the planar linkage chain too. So, the methods of identifying isomorphism are unified in the planar kinematic chain that has or hasn＇t higher pairs with or without multiple joints. And it has some characters such as visual, simple and convenient for processing by computer, and so on.展开更多
Let R_1 and R_2 be two rings with unit I. We give some characterizations of ring homomorphisms and ring isomorphisms between R_1 and R_2 in term of complete preservers of fixed points of multipliers, under some mild a...Let R_1 and R_2 be two rings with unit I. We give some characterizations of ring homomorphisms and ring isomorphisms between R_1 and R_2 in term of complete preservers of fixed points of multipliers, under some mild assumption on R_1. Applications to several kinds of operator algebras such as Banach algebras, nest algebras, matrix algebras and standard operator algebras are presented.展开更多
The substitutions of Ti, Fe and Zr into zeolite Y in the aqueous solutions of (NH4)2TiF6, (NH4)3ZrF7 and (NH4)3FeF6 were systematically Investigated. It was found that Ai atoms in the framework can be replaced by some...The substitutions of Ti, Fe and Zr into zeolite Y in the aqueous solutions of (NH4)2TiF6, (NH4)3ZrF7 and (NH4)3FeF6 were systematically Investigated. It was found that Ai atoms in the framework can be replaced by some metallic elements and the extent of substitution depends on the M/A1 ratio of the solution. The maximum allowable M/A1 ratio of the aqueous solution Is related with the radius of the M atom and the stability constant of the MFnm- complex. The substituted zeolite samples with crystallinity greater than 80% were characterized by means of XRD, IR, DTA, TPR and NH3-TPD measurements. The incorporation of Ti, Fe and Zr into the zeolite leads to an increase in the unit cell parameter, a lowering of thermal stability and a red shift of the asymmetric stretching frequency. The extent of these changes is apparently related with the ionic radius of the metallic element and the degree of substitution. The results of various characterization methods show that the het-eroatoms are readily Introduced into the zeolite framework by this preparation method. It was also observed that the substitution of heteroatoms may strengthen or weaken the surface acidity of zeolite Y.展开更多
In nature, iron cations in magnetite are usually isomorphically substituted by divalent (Co, Ni, Zn, Cu, Mn, etc.), trivalent (Al, V, Cr, etc.) and tetravalent (Ti) cations while maintaining the spinel structure. Some...In nature, iron cations in magnetite are usually isomorphically substituted by divalent (Co, Ni, Zn, Cu, Mn, etc.), trivalent (Al, V, Cr, etc.) and tetravalent (Ti) cations while maintaining the spinel structure. Some of the substituting cations, e.g. Cr3+, V3+ and Mn2+, improve the catalytic activity of magnetite in heterogeneous Fenton reaction through the enhancement of hydroxyl radical OH production and the pollutant adsorption.展开更多
An aluminium-substituted framework gallophosphate with occluded triethylamine was synthesized hydrothermally. 27Al MAS NMR spectroscopy indicates that only the tetrahedral coordinated gallium atoms in the gallophospha...An aluminium-substituted framework gallophosphate with occluded triethylamine was synthesized hydrothermally. 27Al MAS NMR spectroscopy indicates that only the tetrahedral coordinated gallium atoms in the gallophosphate are substituted by aluminium atoms. The substitution leads to an evident decrease in cell volume of the crystal. The differences between the original gallophosphate and the aluminium-substituted one are also found for the IR spectrum and the thermal property.展开更多
In this paper, we introduce a new approach to characterize the isomor-phisms of circulant digraphs. In terms of this method, we completely determine theisomorphic classes of circulant digraphs of degree 3. In particul...In this paper, we introduce a new approach to characterize the isomor-phisms of circulant digraphs. In terms of this method, we completely determine theisomorphic classes of circulant digraphs of degree 3. In particular, we characterizethose circulant digraphs of degree 3 which don't satisfy Adam's conjecture.展开更多
There are two kinds of isometric isomorphism in probabilistic metric space theory. The first is that a PM space (E, F) is isometrically isomorphic to another PM space (E', F'), and the second is that a PM spac...There are two kinds of isometric isomorphism in probabilistic metric space theory. The first is that a PM space (E, F) is isometrically isomorphic to another PM space (E', F'), and the second is that a PM space (E, F) is isometrically isomorphic to a generating space of quasi-metric family (E', d(r), r is an element of (0, 1)). This paper establishes the connection between the two kinds of isometric isomorphism.展开更多
This paper provides several linear isomorphism theorems for certain nonsymmetric differential operators of sixth order under proper topologies about some complex parameters. From these results, one can, to a large ext...This paper provides several linear isomorphism theorems for certain nonsymmetric differential operators of sixth order under proper topologies about some complex parameters. From these results, one can, to a large extent, explain and control the stability of some objects in their moving processes.展开更多
Let L:=-△+V be the Schrodinger operator on R^(n)with n≥3,where V is a non-negative potential satisfying△^(-1)(V)∈L^(∞)(R^(n)).Let w be an L-harmonic function,determined by V,satisfying that there exists a positiv...Let L:=-△+V be the Schrodinger operator on R^(n)with n≥3,where V is a non-negative potential satisfying△^(-1)(V)∈L^(∞)(R^(n)).Let w be an L-harmonic function,determined by V,satisfying that there exists a positive constantδsuch that,for any x∈Rn,0<δ≤w(x)≤1.Assume that p(·):R^(n)→(0,1]is a variable exponent satisfying the globally log-Hölder continuous condition.In this article,the authors show that the mappings HL^(p)(·))(R^(n))■f■wf∈H^(p)(·)(R^(n))and HL^(p(·))(R^(n))■f■(-△)^(1/2)L^(-1/2)(f)∈H^(p(·))(R^(n))are isomorphisms between the variable Hardy spaces HL^(p(·))(R^(n)),associated with L,and the variable Hardy spaces H^(p(·))(R^(n)).展开更多
文摘Metal oxides as support for constructing precious metal single-atom catalysts hold great promise for a wide range of industrial applications,but achieving a high-loading of thermally stable metal single atoms on such supports has been challenging.Herein,we report an innovative strategy for the fabrication of high-density single-atoms(Rh,Ru,Pd)catalysts on CaAl-layered double hydroxides(CaAl-LDH)via isomorphous substitution.The Rh species have occupied Ca^(2+)vacancies within CaAl-LDH laminate by ion-exchange,facilitating a substantial loading of isolated Rh single-atoms.Such catalysts displayed superior performance in the selective hydrogenation to quinoline,pivotal for liquid organic hydrogen storage,and the universality for the hydrogenation of N-heterocyclic aromatic hydrocarbons was also verified.Combining the experimental results and density functional theory calculations,the pathway of quinoline hydrogenation over Rh1CaAl-LDH was proposed.This synthetic strategy marks a significant advancement in the field of single-atom catalysts,expanding their horizons in green chemical processes.
文摘We analyze existence and uniqueness of solutions for perturbations of a Jensen functional inequality in several variables.Applications in connection with asymptotic behaviors of isomorphisms,derivations and n-Jordan derivations on Banach algebras are also provided.The results of this paper correct and improve the main results of[12,16,22,23]and improve the corresponding results in[2,9,27],but under weaker assumptions.
基金supported by the Daejin University grants in 2010
文摘In this article, we prove the Hyers-Ulam-Rassias stability of the following Cauchy-Jensen functional inequality：‖f （x） ＋ f （y） ＋ 2f （z） ＋ 2f （w）‖ ≤‖ 2f x ＋ y2 ＋ z ＋ w ‖（0.1）This is applied to investigate isomorphisms between C＊-algebras, Lie C＊-algebras and JC＊-algebras, and derivations on C＊-algebras, Lie C＊-algebras and JC＊-algebras, associated with the Cauchy-Jensen functional equation 2f （x ＋ y/2 ＋ z ＋ w） = f（x） ＋ f（y） ＋ 2f（z） ＋ 2f（w）.
基金the National Natural Science Foundation of China (60373089, 60674106, and 60533010)the National High Technology Research and Development "863" Program (2006AA01Z104)
文摘Evolutionary computation techniques have mostly been used to solve various optimization problems, and it is well known that graph isomorphism problem （GIP） is a nondeterministic polynomial problem. A simulated annealing （SA） algorithm for detecting graph isomorphism is proposed, and the proposed SA algorithm is well suited to deal with random graphs with large size. To verify the validity of the proposed SA algorithm, simulations are performed on three pairs of small graphs and four pairs of large random graphs with edge densities 0.5, 0.1, and 0.01, respectively. The simulation results show that the proposed SA algorithm can detect graph isomorphism with a high probability.
基金financially supported by the National Natural Science Foundation of China (Nos. 51364005, 51564003 and 51574094)
文摘Most of the phosphorite deposits in the world contain isomorphism rare earths （RE） which are considerably difficult to be leached into solution in the wet phos- phoric acid process. In this work, a systematic study of leaching RE using sulfuric acid, phosphoric acid, mixed acid and two-step leaching of phosphoric acid and sulfuric acid was performed. The aims are to illuminate the main factors that inhibit RE leaching and to provide insights into the further enrichment of RE in the wet phosphoric acid solution. The results indicate that H2SO4 is not an effective acid for leaching isomorphism RE from phosphorite ore. The low RE leaching efficiency attributes to the RE cocrystallized and encapsulated by phosphogypsum （PG） as well as the precipitation of RE by RE sulfates or phosphates. High concentration of H3PO4 can enhance the dissolution and diffusion of RE ions. Hence, the optimized leaching mode of improving RE leaching efficiency is to adequately dissolve phosphorite ores in high concentration of H3PO4 solution and then add H2SO4 to crystallize PG. The effect of corystallization or encapsulation of PG on RE can be decreased due to the crystallizing mode of PG in the bulk solution instead of on the interface of solid reactants. RE leaching efficiency can be high up to 65% by the optimized leaching mode.
文摘Basing on the papers from [1] to [4], this paper gives some further research,mainly solves the following problems:(1) It proved that several theorems of subgroup which have been raised to the hypergroup are still true.(2) It proved that the isomorphous relationship of the bottomgroups which guid to the hypergroup can still keep such relationship.(3) It proved that the basic isomorphous Theorem and the homogenous Theorem of the bottomgroup which raise to the hypergroup are still true.(4) It point out that when the isomorphous bottomgroups have been raised to the hypergroup,the conditions which form the isomorphism should be lessened.
基金The Strategic Priority Research Program of the CAS,No.XDA20040400National Natural Science Foundation of China,No.41801114。
文摘This study undertakes a systematic examination of characteristics of the spatio-temporal evolution of industrial economies in Central Asia from the perspectives of industrial scale,structural rationality,industrial competitiveness,and industrial isomorphism.The results show that industrial structures in Central Asian countries are becoming increasingly advanced,with certain differences among them in the characteristics of this evolution.Kazakhstan has long had a tertiary-secondary-primary industrial pattern,and productive services have played an increasingly prominent role in the development of its tertiary industry.The transformation of the industrial structure in Uzbekistan,from a secondary-tertiary-primary pattern at its independence from the Soviet Union to a tertiary-secondary-primary pattern,is apparent.Tajikistan's industrial structure has also changed significantly in recent times.Its secondary industries shrunk while tertiary industries developed rapidly.In Kyrgyzstan,the ratios of secondary and tertiary industries to total industrial output have fluctuated significantly while considerable progress has been made in the service sector.The industrial structure of Turkmenistan is significantly lower than the other countries,and Turkmenistan is the only country in the Central Asian region which still shows a tertiary-secondary-primary industrial pattern.The feasibility and competitiveness of the industrial structures of these five Central Asian countries have different characteristics.Kazakhstan has structural advantages but lags in competitiveness,Uzbekistan is driven by both structural and competitive advantages,Tajikistan enjoys structural advantages while Kyrgyzstan lags behind in competitiveness,and Turkmenistan has a competitiveness-driven economy.Furthermore,values of the similar coefficient index of the three industrial structures in these countries were mostly above 0.95,the coefficients of the secondary industrial subdivisions in some countries were below 0.85,and those of tertiary industrial subdivisions among most countries were above 0.89,indicating considerable similarities in industrial structure among them.These findings are important in the context of establishing an effective industrial development strategy for the Silk Road Economic Belt,improving international cooperation,and upgrading industrial structures to achieve economic prosperity.
基金National Natural Science Foundation of China(10571090)the Research Fund for the Doctoral Program of Higher Education(20060055010)
文摘If T is an isomorphism of （c0） into C（Ω） （where Ω is a sequentially compact and paracompact space, or a compact metric space in particular）, which satisfies the condition ｜｜T｜｜·｜｜T^-1｜｜ ≤ 1 ＋ε for some ε ∈ （0,1/5）, then T/｜｜T｜｜ is close to an isometry with an error less than 9ε. The proof of this article is simple without using the dual space or adjoint operator.
基金Supported by National Natural Science Foundation of China(Grant Nos.51675488,51975534)Zhejiang Provincial Natural Science Foundation of China(Grant No.LY19E050021)。
文摘Isomorphism detection is fundamental to the synthesis and innovative design of kinematic chains(KCs).The detection can be performed accurately by using the similarity of KCs.However,there are very few works on isomorphism detection based on the properties of similar vertices.In this paper,an ameliorated multi-order adjacent vertex assignment sequence(AMAVS)method is proposed to seek out similar vertices and identify the isomorphism of the planar KCs.First,the specific definition of AMAVS is described.Through the calculation of the AMAVS,the adjacent vertex value sequence reflecting the uniqueness of the topology features is established.Based on the value sequence,all possible similar vertices,corresponding relations,and isomorphism discrimination can be realized.By checking the topological graph of KCs with a different number of links,the effectiveness and efficiency of the proposed method are verified.Finally,the method is employed to implement the similar vertices and isomorphism detection of all the 9-link 2-D0F(degree of freedom)planar KCs.
基金Supported by the National Natural Science Foundation of China(Grant No.10901134)the Science Foundation of the Department of Education of Yunnan Province(Grant No.2011Y478)
文摘In this paper we study the isomorphisms of two ＊-bisimple type A ω2-semigroups such that D^＊ = ^~D） and obtain a criterion for isomorphisms of two such semigroups.
基金Projects(61272142,61103082,61003075,61170261,61103193)supported by the National Natural Science Foundation of ChinaProject supported by Funds for New Century Excellent Talents in University of ChinaProjects(2012AA01A301,2012AA010901)supported by the National High Technology Research and Development Program of China
文摘A novel framework for parallel subgraph isomorphism on GPUs is proposed, named GPUSI, which consists of GPU region exploration and GPU subgraph matching. The GPUSI iteratively enumerates subgraph instances and solves the subgraph isomorphism in a divide-and-conquer fashion. The framework completely relies on the graph traversal, and avoids the explicit join operation. Moreover, in order to improve its performance, a task-queue based method and the virtual-CSR graph structure are used to balance the workload among warps, and warp-centric programming model is used to balance the workload among threads in a warp. The prototype of GPUSI is implemented, and comprehensive experiments of various graph isomorphism operations are carried on diverse large graphs. The experiments clearly demonstrate that GPUSI has good scalability and can achieve speed-up of 1.4–2.6 compared to the state-of-the-art solutions.
文摘The adjacent matrix method for identifying isomorphism to planar kinematic chain with multiple joints and higher pairs is presented. The topological invariants of the planar kinematic chain can be calculated and compared by adjacent matrix. The quantity of calculation can be reduced effectively using the several divisions of bars and the reconfiguration of the adjacent matrix. As two structural characteristics of adjacent matrix, the number of division and division code are presented. It can be identified that two kinematic chains are isomorphic or not by comparing the structural characteristics of their adjacent matrixes using a method called matching row-to-row. This method may be applied to the planar linkage chain too. So, the methods of identifying isomorphism are unified in the planar kinematic chain that has or hasn＇t higher pairs with or without multiple joints. And it has some characters such as visual, simple and convenient for processing by computer, and so on.
基金Supported by the National Natural Science Foundation of China(Grant No.11671294)
文摘Let R_1 and R_2 be two rings with unit I. We give some characterizations of ring homomorphisms and ring isomorphisms between R_1 and R_2 in term of complete preservers of fixed points of multipliers, under some mild assumption on R_1. Applications to several kinds of operator algebras such as Banach algebras, nest algebras, matrix algebras and standard operator algebras are presented.
文摘The substitutions of Ti, Fe and Zr into zeolite Y in the aqueous solutions of (NH4)2TiF6, (NH4)3ZrF7 and (NH4)3FeF6 were systematically Investigated. It was found that Ai atoms in the framework can be replaced by some metallic elements and the extent of substitution depends on the M/A1 ratio of the solution. The maximum allowable M/A1 ratio of the aqueous solution Is related with the radius of the M atom and the stability constant of the MFnm- complex. The substituted zeolite samples with crystallinity greater than 80% were characterized by means of XRD, IR, DTA, TPR and NH3-TPD measurements. The incorporation of Ti, Fe and Zr into the zeolite leads to an increase in the unit cell parameter, a lowering of thermal stability and a red shift of the asymmetric stretching frequency. The extent of these changes is apparently related with the ionic radius of the metallic element and the degree of substitution. The results of various characterization methods show that the het-eroatoms are readily Introduced into the zeolite framework by this preparation method. It was also observed that the substitution of heteroatoms may strengthen or weaken the surface acidity of zeolite Y.
文摘In nature, iron cations in magnetite are usually isomorphically substituted by divalent (Co, Ni, Zn, Cu, Mn, etc.), trivalent (Al, V, Cr, etc.) and tetravalent (Ti) cations while maintaining the spinel structure. Some of the substituting cations, e.g. Cr3+, V3+ and Mn2+, improve the catalytic activity of magnetite in heterogeneous Fenton reaction through the enhancement of hydroxyl radical OH production and the pollutant adsorption.
基金Supported by the National Natural Science Foundation of China
文摘An aluminium-substituted framework gallophosphate with occluded triethylamine was synthesized hydrothermally. 27Al MAS NMR spectroscopy indicates that only the tetrahedral coordinated gallium atoms in the gallophosphate are substituted by aluminium atoms. The substitution leads to an evident decrease in cell volume of the crystal. The differences between the original gallophosphate and the aluminium-substituted one are also found for the IR spectrum and the thermal property.
基金Supported by the National Natural Science Foundation of China.
文摘In this paper, we introduce a new approach to characterize the isomor-phisms of circulant digraphs. In terms of this method, we completely determine theisomorphic classes of circulant digraphs of degree 3. In particular, we characterizethose circulant digraphs of degree 3 which don't satisfy Adam's conjecture.
文摘There are two kinds of isometric isomorphism in probabilistic metric space theory. The first is that a PM space (E, F) is isometrically isomorphic to another PM space (E', F'), and the second is that a PM space (E, F) is isometrically isomorphic to a generating space of quasi-metric family (E', d(r), r is an element of (0, 1)). This paper establishes the connection between the two kinds of isometric isomorphism.
文摘This paper provides several linear isomorphism theorems for certain nonsymmetric differential operators of sixth order under proper topologies about some complex parameters. From these results, one can, to a large extent, explain and control the stability of some objects in their moving processes.
基金supported by the National Natural Science Foundation of China(11801555 and 11971058)the Fundamental Research Funds for the Central Universities(2020YQLX02)supported by the National Natural Science Foundation of China(11971058,11761131002 and 11671185)。
文摘Let L:=-△+V be the Schrodinger operator on R^(n)with n≥3,where V is a non-negative potential satisfying△^(-1)(V)∈L^(∞)(R^(n)).Let w be an L-harmonic function,determined by V,satisfying that there exists a positive constantδsuch that,for any x∈Rn,0<δ≤w(x)≤1.Assume that p(·):R^(n)→(0,1]is a variable exponent satisfying the globally log-Hölder continuous condition.In this article,the authors show that the mappings HL^(p)(·))(R^(n))■f■wf∈H^(p)(·)(R^(n))and HL^(p(·))(R^(n))■f■(-△)^(1/2)L^(-1/2)(f)∈H^(p(·))(R^(n))are isomorphisms between the variable Hardy spaces HL^(p(·))(R^(n)),associated with L,and the variable Hardy spaces H^(p(·))(R^(n)).
