A new 2-D Bi(3+) coordination polymer {Bi4(μ3-O)2(μ4-O)2(C7H3NO4)2}n(1,C7H3NO4 = pyridine-2,6-dicarboxylate) containing(6,5)-connected topological sheet with the Schl?fli symbol of(4~4·6~3·8...A new 2-D Bi(3+) coordination polymer {Bi4(μ3-O)2(μ4-O)2(C7H3NO4)2}n(1,C7H3NO4 = pyridine-2,6-dicarboxylate) containing(6,5)-connected topological sheet with the Schl?fli symbol of(4~4·6~3·8~4·12~4)(4~5·6~4·8) has been synthesized by an ionothermal method using the ionic liquid 1-ethyl-3-methylimidazolium bromide([Emim]Br) as solvent,and characterized by C,H and N elemental analysis,energy-dispersive X-ray spectroscopy(EDS),infrared spectrum(IR spectrum) and single-crystal X-ray diffraction.The results indicate that 1 belongs to the monoclinic system,space group P21/n with a = 13.766(7),b = 4.142(2),c = 16.439(8) ?,β = 99.099(9)°,Z = 2,V = 925.6(8) ?~3,Dc = 4.414 g·cm^(-3),F(000) = 1064,μ = 37.985 mm-1,the final R = 0.0326,wR = 0.0727 and S = 1.022.The molecular structural units [Bi4(μ3-O)2(μ4-O)2(C7H3NO4)2] are connected to each other via bridging O atoms,extending into an interesting 2-D layered structure.These resulting layers are further assembled by weak C-H…O hydrogen bonds into a 3-D supramolecular architecture.Moreover,its thermal stability and the luminescent properties have been also studied.展开更多
A chiral lanthanide metal-organic framework based on enantiopure camphoric acid (D-H2cam), [Nd3(D-cam)8(H2O)4Cl]n (1), has been synthesized and characterized by single-crystal X-ray structural analysis, elemen...A chiral lanthanide metal-organic framework based on enantiopure camphoric acid (D-H2cam), [Nd3(D-cam)8(H2O)4Cl]n (1), has been synthesized and characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Crystal data for the title compound are as follows: orthorhombic system, space group P212121 with a = 13.8287(7), b = 14.0715(7), c = 25.7403(12) A^°, V = 5008.8(4) A^°3, Mr = 1333.08, Z = 4, F(000) = 2644, Dc = 1.768 g/cm^3, μ(MoKα) = 3.189 mm^-1, the final R = 0.0351 and wR = 0.0814 (I 〉 2σ(I)). Compound 1 displays an 8-connected bcu topology 3D framework and hydrogen-bonding interactions stabilize the solid-state structure. The vibrational circular dichroism (VCD) spectrum and second-order nonlinear optical effect of compound 1 have been studied in the solid state.展开更多
By using "pillaring" strategy, a new Co(Ⅱ)-MOF, [Co_2(abtc)(bimb)_2]·2H_2O(1, H_4abtc = 3,3?,5,5?-azobenzenetetracarboxylic acid, bimb = 4,4?-bis(imidazole-1-ylmethyl)biphenyl), has been solvother...By using "pillaring" strategy, a new Co(Ⅱ)-MOF, [Co_2(abtc)(bimb)_2]·2H_2O(1, H_4abtc = 3,3?,5,5?-azobenzenetetracarboxylic acid, bimb = 4,4?-bis(imidazole-1-ylmethyl)biphenyl), has been solvothermally synthesized and structurally characterized. The structural determination revealed that 1 features a 3D pillar-layered framework with(4,8)-connected {4^4.6^2}{4^8.6^(20)} topology based on dinuclear Co(Ⅱ)-SBUs. The magnetic investigation shows that the dominant antiferromagnetic coupling is observed in compound 1.展开更多
Two new metal-organic frameworks(MOFs), namely, [Co_2(L_1)(bix)(μ_3-OH)]·2H_2O(1) and [Co_2(L_2)(bix)(μ_3-OH)]·2.5H_2O(2)(H_3L_1 = 5-oxyacetate isophthalic acid, H_3L_2 = 3,5-bis-oxyacet...Two new metal-organic frameworks(MOFs), namely, [Co_2(L_1)(bix)(μ_3-OH)]·2H_2O(1) and [Co_2(L_2)(bix)(μ_3-OH)]·2.5H_2O(2)(H_3L_1 = 5-oxyacetate isophthalic acid, H_3L_2 = 3,5-bis-oxyacetate-benzoic acid, bix = 1,4-bis(imidazol-1-ylmethyl)benzene), have been synthesized under hydrothermal conditions. Their structures were determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra, and powder X-ray diffraction(PXRD) analysis. Both complexes 1 and 2 demonstrate identical three-dimensional(3D)(3,8)-connected tfz-d nets with(4~3)_2(4~6·6^(18)·8~4) topologies, where the tetranuclear [Co_4(μ_3-OH)_2] clusters act as 8-connected nodes and aromatic multicarboxylic ligands as 3-connected nodes. The results show that the ligands with different geometrical conformations can form products with the same topological structures. Their thermal and magnetic properties were also investigated.展开更多
A new metal-organic framework, {[Cd(DPA)(OBA)]'(HzO)}n (1, DPA = 4,4"-dipyri- dylamine, H2OBA = 4,4"-oxybisbenzoic acid), has been synthesized and characterized by elemental analysis, IR and single-crystal ...A new metal-organic framework, {[Cd(DPA)(OBA)]'(HzO)}n (1, DPA = 4,4"-dipyri- dylamine, H2OBA = 4,4"-oxybisbenzoic acid), has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. Single-crystal X-ray analysis shows that it is a 3-D framework. Complex 1 crystallizes in monoclinic, space group C2/c with a = 21.699(7), b = 12.192(4), c = 17.566(5) A, β = 105.254(5)°, V = 4483.43 A3, Z = 8, Dc = 1.653 g/cm3, p = 1.021 mm^-1], F(000) = 2240, the final R = 0.0307, wR = 0.0867 (I 〉 2σ(I)). Complex I exhibits a rare three-dimensional highly 8-connected LOMFOI topology with a point symbol of {424"64}. Thermogravimetric analysis shows that the decomposition temperature of the host framework of the complex is above 400 ℃.展开更多
A subset S of V is called a k-connected dominating set if S is a dominating set and the induced subgraph S has at most k components.The k-connected domination number γck(G) of G is the minimum cardinality taken ove...A subset S of V is called a k-connected dominating set if S is a dominating set and the induced subgraph S has at most k components.The k-connected domination number γck(G) of G is the minimum cardinality taken over all minimal k-connected dominating sets of G.In this paper,we characterize trees and unicyclic graphs with equal connected domination and 2-connected domination numbers.展开更多
Similar to Nomizu-Pinkall's geometric characterization of the Cayley surface and Hu-Li-Zhang's characterization of the Cayley hypersurface,how can one characterize the generalized Cayley hypersurfaces?In this ...Similar to Nomizu-Pinkall's geometric characterization of the Cayley surface and Hu-Li-Zhang's characterization of the Cayley hypersurface,how can one characterize the generalized Cayley hypersurfaces?In this paper,by the affineα-connection of statistical manifolds,we study affine hypersurfaces with parallel cubic form relative to the affineα-connection.As the main results,we complete the classification of such hypersurfaces if its affine metric is either definite,or Lorentzian withα≠-1.Moreover,we give a new characterization of the generalized Cayley hypersurfaces to answer the question.展开更多
Sampling-based planning algorithms play an important role in high degree-of-freedom motion planning(MP)problems,in which rapidly-exploring random tree(RRT)and the faster bidirectional RRT(named RRT-Connect)algorithms ...Sampling-based planning algorithms play an important role in high degree-of-freedom motion planning(MP)problems,in which rapidly-exploring random tree(RRT)and the faster bidirectional RRT(named RRT-Connect)algorithms have achieved good results in many planning tasks.However,sampling-based methods have the inherent defect of having difficultly in solving planning problems with narrow passages.Therefore,several algorithms have been proposed to overcome these drawbacks.As one of the improved algorithms,Rapidlyexploring random vines(RRV)can achieve better results,but it may perform worse in cluttered environments and has a certain environmental selectivity.In this paper,we present a new improved planning method based on RRT-Connect and RRV,named adaptive RRT-Connect(ARRT-Connect),which deals well with the narrow passage environments while retaining the ability of RRT algorithms to plan paths in other environments.The proposed planner is shown to be adaptable to a variety of environments and can accomplish path planning in a short time.展开更多
Image output by computer is done row by row,the shortcoming of which is that we cannot know the topological relations between points at the image boundary.To obtain the closed boundary of the target from an image and ...Image output by computer is done row by row,the shortcoming of which is that we cannot know the topological relations between points at the image boundary.To obtain the closed boundary of the target from an image and turn points' row permutation of boundary into sequence permutation,an algorithm based on 4-connection relation of pixel points is proposed and the analysis of its correctness and complexity is given.Compared with classical operators and existing method,the single pixel boundary extracted from gray images by this algorithm is more complete and more distinct.Moreover,it has a lower time complexity and can eliminate the noise inside and outside the target area.The obtained sequence permutation of points is also conducive to follow-up image processing.展开更多
The organic-inorganic hybrid polymer [Mn(mbbimb)2(1,5-nds)]n 1 has been synthesized using 1,5-naphthalenedisulfonate (1,5-nds) and 1,3-bis(benzimidazol-1-ylmethyl)- 2,4,structure analysis indicates that 1 crys...The organic-inorganic hybrid polymer [Mn(mbbimb)2(1,5-nds)]n 1 has been synthesized using 1,5-naphthalenedisulfonate (1,5-nds) and 1,3-bis(benzimidazol-1-ylmethyl)- 2,4,structure analysis indicates that 1 crystallizes in monoclinic, space group C2/c with a=21.3546(17), b=11.8841(7), c=22.1588(16)A, β=108.058(3)°, C60H54MnN8O6S2, Mr=1102.17, Z=4, V=5346.5(7)A^3, Dc=1.369 g/cm^3, μ=0.386 mm^-1, F(000)=2300, S=1.091, R=0.0634 and wR=0.1559 for 4641 observed reflections (I 〉 2σ(I)). The Mn center is six-coordinated to furnish a distorted octahedral geometry, and the overall framework is a 6-connected 3D net.展开更多
This article aims to present new terms of single-valued neutrosophic notions in theˇSostak sense,known as singlevalued neutrosophic regularity spaces.Concepts such as r-single-valued neutrosophic semi£-open,r-single...This article aims to present new terms of single-valued neutrosophic notions in theˇSostak sense,known as singlevalued neutrosophic regularity spaces.Concepts such as r-single-valued neutrosophic semi£-open,r-single-valued neutrosophic pre-£-open,r-single valued neutrosophic regular-£-open and r-single valued neutrosophicα£-open are defined and their properties are studied as well as the relationship between them.Moreover,we introduce the concept of r-single valued neutrosophicθ£-cluster point and r-single-valued neutrosophicγ£-cluster point,r-θ£-closed,andθ£-closure operators and study some of their properties.Also,we present and investigate the notions of r-single-valued neutrosophicθ£-connectedness and r-single valued neutrosophicδ£-connectedness and investigate relationship with single-valued neutrosophic almost£-regular.We compare all these forms of connectedness and investigate their properties in single-valued neutrosophic semiregular and single-valued neutrosophic almost regular in neutrosophic ideal topological spaces inˇSostak sense.The usefulness of these concepts are incorporated to multiple attribute groups of comparison within the connectedness and separateness ofθ£andδ£.展开更多
基金Project supported by the National Natural Science Foundation of China(No.21601095)
文摘A new 2-D Bi(3+) coordination polymer {Bi4(μ3-O)2(μ4-O)2(C7H3NO4)2}n(1,C7H3NO4 = pyridine-2,6-dicarboxylate) containing(6,5)-connected topological sheet with the Schl?fli symbol of(4~4·6~3·8~4·12~4)(4~5·6~4·8) has been synthesized by an ionothermal method using the ionic liquid 1-ethyl-3-methylimidazolium bromide([Emim]Br) as solvent,and characterized by C,H and N elemental analysis,energy-dispersive X-ray spectroscopy(EDS),infrared spectrum(IR spectrum) and single-crystal X-ray diffraction.The results indicate that 1 belongs to the monoclinic system,space group P21/n with a = 13.766(7),b = 4.142(2),c = 16.439(8) ?,β = 99.099(9)°,Z = 2,V = 925.6(8) ?~3,Dc = 4.414 g·cm^(-3),F(000) = 1064,μ = 37.985 mm-1,the final R = 0.0326,wR = 0.0727 and S = 1.022.The molecular structural units [Bi4(μ3-O)2(μ4-O)2(C7H3NO4)2] are connected to each other via bridging O atoms,extending into an interesting 2-D layered structure.These resulting layers are further assembled by weak C-H…O hydrogen bonds into a 3-D supramolecular architecture.Moreover,its thermal stability and the luminescent properties have been also studied.
基金supported by National Natural Science Foundation of China(21401147)Basic Research Program of Natural Science from Shaanxi Provincial Government(2015JQ2032)+2 种基金Scientific Research Program from Education Department of Shaanxi Provincial Government(2013JK0654)Opening Foundation from State Key Laboratory of Coordination Chemistry in Nanjing University(201219)the Program for Distinguished Young Scholars of Xi’an Polytechnic University(201403)
文摘A chiral lanthanide metal-organic framework based on enantiopure camphoric acid (D-H2cam), [Nd3(D-cam)8(H2O)4Cl]n (1), has been synthesized and characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Crystal data for the title compound are as follows: orthorhombic system, space group P212121 with a = 13.8287(7), b = 14.0715(7), c = 25.7403(12) A^°, V = 5008.8(4) A^°3, Mr = 1333.08, Z = 4, F(000) = 2644, Dc = 1.768 g/cm^3, μ(MoKα) = 3.189 mm^-1, the final R = 0.0351 and wR = 0.0814 (I 〉 2σ(I)). Compound 1 displays an 8-connected bcu topology 3D framework and hydrogen-bonding interactions stabilize the solid-state structure. The vibrational circular dichroism (VCD) spectrum and second-order nonlinear optical effect of compound 1 have been studied in the solid state.
基金Supported by the National Natural Science Foundation of China(Nos.21201109,21373122 and 21301106)
文摘By using "pillaring" strategy, a new Co(Ⅱ)-MOF, [Co_2(abtc)(bimb)_2]·2H_2O(1, H_4abtc = 3,3?,5,5?-azobenzenetetracarboxylic acid, bimb = 4,4?-bis(imidazole-1-ylmethyl)biphenyl), has been solvothermally synthesized and structurally characterized. The structural determination revealed that 1 features a 3D pillar-layered framework with(4,8)-connected {4^4.6^2}{4^8.6^(20)} topology based on dinuclear Co(Ⅱ)-SBUs. The magnetic investigation shows that the dominant antiferromagnetic coupling is observed in compound 1.
基金supported by the application basis research key project of Yunnan Province science and technology department(201401CB00299)the major project of Qujing Normal University(2012ZD002)
文摘Two new metal-organic frameworks(MOFs), namely, [Co_2(L_1)(bix)(μ_3-OH)]·2H_2O(1) and [Co_2(L_2)(bix)(μ_3-OH)]·2.5H_2O(2)(H_3L_1 = 5-oxyacetate isophthalic acid, H_3L_2 = 3,5-bis-oxyacetate-benzoic acid, bix = 1,4-bis(imidazol-1-ylmethyl)benzene), have been synthesized under hydrothermal conditions. Their structures were determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra, and powder X-ray diffraction(PXRD) analysis. Both complexes 1 and 2 demonstrate identical three-dimensional(3D)(3,8)-connected tfz-d nets with(4~3)_2(4~6·6^(18)·8~4) topologies, where the tetranuclear [Co_4(μ_3-OH)_2] clusters act as 8-connected nodes and aromatic multicarboxylic ligands as 3-connected nodes. The results show that the ligands with different geometrical conformations can form products with the same topological structures. Their thermal and magnetic properties were also investigated.
基金supported by the National Ministry of Science and Technology of China(2012CB821702)the National Science Foundation of China(21073192,21203194 and 21233009)the Science Foundation of CAS and Fujian Province for research funding support(KJCX2-YW-H20)
文摘A new metal-organic framework, {[Cd(DPA)(OBA)]'(HzO)}n (1, DPA = 4,4"-dipyri- dylamine, H2OBA = 4,4"-oxybisbenzoic acid), has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. Single-crystal X-ray analysis shows that it is a 3-D framework. Complex 1 crystallizes in monoclinic, space group C2/c with a = 21.699(7), b = 12.192(4), c = 17.566(5) A, β = 105.254(5)°, V = 4483.43 A3, Z = 8, Dc = 1.653 g/cm3, p = 1.021 mm^-1], F(000) = 2240, the final R = 0.0307, wR = 0.0867 (I 〉 2σ(I)). Complex I exhibits a rare three-dimensional highly 8-connected LOMFOI topology with a point symbol of {424"64}. Thermogravimetric analysis shows that the decomposition temperature of the host framework of the complex is above 400 ℃.
文摘A subset S of V is called a k-connected dominating set if S is a dominating set and the induced subgraph S has at most k components.The k-connected domination number γck(G) of G is the minimum cardinality taken over all minimal k-connected dominating sets of G.In this paper,we characterize trees and unicyclic graphs with equal connected domination and 2-connected domination numbers.
基金supported by NNSF of China(Grant No.11401173)supported by NNSF of China(Grant No.12171437)supported by NNSF of China(Grant No.12101194)。
文摘Similar to Nomizu-Pinkall's geometric characterization of the Cayley surface and Hu-Li-Zhang's characterization of the Cayley hypersurface,how can one characterize the generalized Cayley hypersurfaces?In this paper,by the affineα-connection of statistical manifolds,we study affine hypersurfaces with parallel cubic form relative to the affineα-connection.As the main results,we complete the classification of such hypersurfaces if its affine metric is either definite,or Lorentzian withα≠-1.Moreover,we give a new characterization of the generalized Cayley hypersurfaces to answer the question.
基金supported in part by the National Science Foundation of China(61976175,91648208)the Key Project of Natural Science Basic Research Plan in Shaanxi Province of China(2019JZ-05)。
文摘Sampling-based planning algorithms play an important role in high degree-of-freedom motion planning(MP)problems,in which rapidly-exploring random tree(RRT)and the faster bidirectional RRT(named RRT-Connect)algorithms have achieved good results in many planning tasks.However,sampling-based methods have the inherent defect of having difficultly in solving planning problems with narrow passages.Therefore,several algorithms have been proposed to overcome these drawbacks.As one of the improved algorithms,Rapidlyexploring random vines(RRV)can achieve better results,but it may perform worse in cluttered environments and has a certain environmental selectivity.In this paper,we present a new improved planning method based on RRT-Connect and RRV,named adaptive RRT-Connect(ARRT-Connect),which deals well with the narrow passage environments while retaining the ability of RRT algorithms to plan paths in other environments.The proposed planner is shown to be adaptable to a variety of environments and can accomplish path planning in a short time.
基金Sponsored by the National Natural Science Foundation of China (60773044 )PLA General Armament Department Key Foundation(9140A26010308BQ0178)
文摘Image output by computer is done row by row,the shortcoming of which is that we cannot know the topological relations between points at the image boundary.To obtain the closed boundary of the target from an image and turn points' row permutation of boundary into sequence permutation,an algorithm based on 4-connection relation of pixel points is proposed and the analysis of its correctness and complexity is given.Compared with classical operators and existing method,the single pixel boundary extracted from gray images by this algorithm is more complete and more distinct.Moreover,it has a lower time complexity and can eliminate the noise inside and outside the target area.The obtained sequence permutation of points is also conducive to follow-up image processing.
基金This work was supported by the State Key Laboratory of Structural Chemistry, the Ministry of Science and Technology of China (001CB108906)the National Natural Science Foundation of China (20333070)
文摘The organic-inorganic hybrid polymer [Mn(mbbimb)2(1,5-nds)]n 1 has been synthesized using 1,5-naphthalenedisulfonate (1,5-nds) and 1,3-bis(benzimidazol-1-ylmethyl)- 2,4,structure analysis indicates that 1 crystallizes in monoclinic, space group C2/c with a=21.3546(17), b=11.8841(7), c=22.1588(16)A, β=108.058(3)°, C60H54MnN8O6S2, Mr=1102.17, Z=4, V=5346.5(7)A^3, Dc=1.369 g/cm^3, μ=0.386 mm^-1, F(000)=2300, S=1.091, R=0.0634 and wR=0.1559 for 4641 observed reflections (I 〉 2σ(I)). The Mn center is six-coordinated to furnish a distorted octahedral geometry, and the overall framework is a 6-connected 3D net.
文摘This article aims to present new terms of single-valued neutrosophic notions in theˇSostak sense,known as singlevalued neutrosophic regularity spaces.Concepts such as r-single-valued neutrosophic semi£-open,r-single-valued neutrosophic pre-£-open,r-single valued neutrosophic regular-£-open and r-single valued neutrosophicα£-open are defined and their properties are studied as well as the relationship between them.Moreover,we introduce the concept of r-single valued neutrosophicθ£-cluster point and r-single-valued neutrosophicγ£-cluster point,r-θ£-closed,andθ£-closure operators and study some of their properties.Also,we present and investigate the notions of r-single-valued neutrosophicθ£-connectedness and r-single valued neutrosophicδ£-connectedness and investigate relationship with single-valued neutrosophic almost£-regular.We compare all these forms of connectedness and investigate their properties in single-valued neutrosophic semiregular and single-valued neutrosophic almost regular in neutrosophic ideal topological spaces inˇSostak sense.The usefulness of these concepts are incorporated to multiple attribute groups of comparison within the connectedness and separateness ofθ£andδ£.