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Synthesis, Crystal Structure and Gas Adsorption of a Two-fold Interpenetrated Three-dimensional Framework {[Cd(2-NO_2-BDC)(4,4?-DPA)]·(DMF)}_n 被引量:1
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作者 刘瑛 王玉玲 +2 位作者 陈岭 刘庆燕 姚阳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第6期921-928,共8页
The reaction of Cd(NO_3)_2·4H_2O with 4,4?-dipyridylacetylene(4,4?-DPA) and 2-nitroterephthalic acid(2-NO_2-H_2BDC) in DMF/H_2O mixed solvent has afforded a compound {[Cd(2-NO_2-BDC)(4,4?-DPA)]·... The reaction of Cd(NO_3)_2·4H_2O with 4,4?-dipyridylacetylene(4,4?-DPA) and 2-nitroterephthalic acid(2-NO_2-H_2BDC) in DMF/H_2O mixed solvent has afforded a compound {[Cd(2-NO_2-BDC)(4,4?-DPA)]·(DMF)}_n(1). Compound 1 has been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetry analysis, and IR spectrum. Compound 1 crystallizes in the monoclinic system, space group P21/n, with a = 12.1488(3), b = 14.6689(3), c = 13.1615(3) ?, β = 111.809(3)o, V = 2177.63(9) ?~3, Z = 4, C_(23)H_(18)N_4O_7 Cd, M_r = 574.81, D_c = 1.753 g/cm^3, μ = 8.523 mm^(-1), F(000) = 1152, the final R = 0.0411 and wR = 0.1064 for 3589 observed reflections with I 〉 2s(I). In compound 1, the Cd(Ⅱ) ions are linked by the carboxylate groups of 2-NO_2-BDC ligands to give a two-dimensional layered structure based on the centrosymmetric dinuclear Cd_2(COO)_2 units, which are further connected by the 4,4?-DPA ligands to produce a three-dimensional framework with pcu topology. Careful examination revealed that compound 1 is a 2-fold interpenetrating framework. Furthermore, the gas adsorption properties of 1 for N_2 and CO_2 have also been investigated. 展开更多
关键词 synthesis 2-fold interpenetrating framework crystal structure gas adsorption
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A New 4-Connected Ni^Ⅱ Coordination Polymer with a Novel 3D 2-Fold Interpenetrated Framework
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作者 郭锋 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第2期187-190,共4页
A coordination polymer [Ni(pbc)2(H2O)]n(Hpbc = 3-pyrid-4-ylbenzoic acid) has been prepared by hydrothermal synthesis and characterized by single-crystal X-ray diffraction,IR and elemental analysis.The crystal is... A coordination polymer [Ni(pbc)2(H2O)]n(Hpbc = 3-pyrid-4-ylbenzoic acid) has been prepared by hydrothermal synthesis and characterized by single-crystal X-ray diffraction,IR and elemental analysis.The crystal is of monoclinic,space group C2/c with a=19.624(5),b=12.029(5),c=19.452(5)A,β=104.45(5)°,C24H18NiN2O5,Mr=473.11,V=4447(2)A^3,Dc=1.413 g/cm^3,F(000)=1952,μ = 0.91 cm^-1,Z = 8,the final R=0.0424 and wR=0.0871 for 3757 reflections with I〉2σ(I).X-ray diffraction analysis reveals that the pbc-ligands act as diconnectors to link two Ni(Ⅱ) centers and adopt two coordination modes of μ2-N,O and μ2-N,O,O to form infinite wavy nickel-carboxylate chains along the bc plane.The topological analysis of compound [Ni(pbc)2(H2O)]n reveals that it is a typical CdS framework. 展开更多
关键词 coordination polymer 2-fold interpenetrated nickel
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与DDRⅡ共舞--七彩虹C.AK4N-M2
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《个人电脑》 2006年第9期125-125,共1页
这款七彩虹C.AK4N-M2从板面布局来看显得比较独特,4条DIMM插槽被别出心裁的安排在了CPU插座与背板之间,此外,PCI-E X1接口旁边安排了6组外形独特的跳线针脚,根据主板说明书中的介绍,这6组跳线是用于控制两条PCI-E X16插槽的通道带宽,
关键词 七彩虹C.AK4n-m2 DDRⅡ 主板 DIMM CPU 背板 插槽 跳线
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Compact Solvmanifolds with a Closed G<sub>2</sub>-Structure
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作者 Marisa Fernández Jonatan Sanchez Jose A. Santisteban 《Advances in Pure Mathematics》 2018年第11期813-829,共17页
We consider a parametrized family of compact G2-calibrated solvmanifolds, and construct associative (so volume-minimizing submanifolds) 3-tori with respect to the closed G2-structure. We also study the Laplacian flow ... We consider a parametrized family of compact G2-calibrated solvmanifolds, and construct associative (so volume-minimizing submanifolds) 3-tori with respect to the closed G2-structure. We also study the Laplacian flow of this closed G2 form on the solvable Lie group underlying to each of these solvmanifolds, and show long time existence of the solution. 展开更多
关键词 G2-Structure Laplacian Flow ASSOCIATIVE 3-folds
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四种参考作物蒸散量综合法的比较 被引量:16
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作者 曹金峰 李玉中 +2 位作者 刘晓英 钟秀丽 赵叶萌 《中国农业气象》 CSCD 北大核心 2015年第4期428-436,共9页
参考作物蒸散量(ET0)的估算是作物需水量计算的关键,诸多估算方法在不同地区具有不同的适应性。本文利用中国农业主产区6个代表站点的气象数据,以FAO 56 Penman-Monteith(PM)为标准,对常用的1963 Penman(Pen63)、FAO 1979 Penman(FAO 79... 参考作物蒸散量(ET0)的估算是作物需水量计算的关键,诸多估算方法在不同地区具有不同的适应性。本文利用中国农业主产区6个代表站点的气象数据,以FAO 56 Penman-Monteith(PM)为标准,对常用的1963 Penman(Pen63)、FAO 1979 Penman(FAO 79)、FAO 24 Penman(FAO 24)及1996Kimberly Penman(Kpen)共4种参考作物蒸散量综合方法进行比较评价。结果表明:(1)Pen63、FAO 79及Kpen的日估算值均比PM估算值偏高,FAO 24偏低,其平均偏差分别为0.28、0.52、0和-0.17mm?d-1,相对偏差为16.0%、25.2%、2.4%、-5.3%,相对均方根误差为12.1%、22.4%、14.2%和13.5%。(2)Pen63、FAO79的月估算值显著高于PM值,在高估最大的5月份平均偏高12.5mm(10.8%)和28.2mm(22.6%)。FAO24表现为低估,低估最大的月份平均偏低11.4mm(8.1%),但在南方站点多数月份的估算值与PM估算值无显著差异。Kpen月估算值与PM估算值相比,既有高估(5-10月),也有低估,高估最大的月份平均偏高19.7mm(14.5%),且在南方站点的秋冬季有近6个月与PM无显著差异。(3)Pen63和FAO79的年值均显著大于PM年值,平均偏高103.8mm(11.8%)和191.5mm(21.3%)。FAO24年平均低估PM值60.9mm(6.3%),Kpen则平均高估50.5mm(5.8%)。(4)时间尺度对评价结果具有一定影响,4种综合法依据日、年值的评价效果排序分别为Pen63>FAO24>Kpen>FAO79和Kpen>FAO24>Pen63>FAO79。在日尺度下4种方法更适于湿润气候,但年尺度下仅FAO79和FAO24较适于湿润气候。可见,4种综合法以Pen63普适性最好,FAO79最低,因此使用FAO79前对其进行适应性评价尤为重要。 展开更多
关键词 参考作物蒸散量(E T0) F A O 7 9 P e N M a N P e N M a n-m O N t e i t h F A O 2 4 K i M b e r l y P e N M a N 农业主产区
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Λ-2-fold环上K_1U~ε的Prestabilization
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作者 游宏 《科学通报》 EI CAS CSCD 北大核心 1991年第11期811-814,共4页
本文利用Vaserstein、Bass等提出的Λ-S,条件研究了满足Δ-S_r(R)≤1条件的一类环(Λ-2-fold)上K_1U^(?)的Prestabilization。 令R为有1的结合环,I是R的一双边理想。
关键词 Λ-2-fold K1U-^ω
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Synthesis,Characterizations,Magnetism and Thermal Degradation of a 2-Fold Interpenetrated 3D Cobalt-Organic Framework 被引量:1
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作者 Linyan Yang Liangliang Xin +8 位作者 Wen Gu Shengyun Liao Peiyao Du Jinlei Tian Yanping Zhang Rui Lv Xiaohua Wei Xin Liu Daizheng Liao 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2014年第3期227-232,共6页
A new coordination polymer,[Co_(2)(L)_(2)(4,4'-bipy)]_(n)·3nH_(2)O(1)based on 5-(3-methyl-5-phenyl-4H-1,2,4-tri-azol-4-yl)isophthalic acid(H_(2)L)and 4,4'-bipyridine(4,4'-bipy)has been hydrothermally ... A new coordination polymer,[Co_(2)(L)_(2)(4,4'-bipy)]_(n)·3nH_(2)O(1)based on 5-(3-methyl-5-phenyl-4H-1,2,4-tri-azol-4-yl)isophthalic acid(H_(2)L)and 4,4'-bipyridine(4,4'-bipy)has been hydrothermally synthesized and character-ized by single-crystal X-ray diffraction,XRPD,IR,and elemental analysis.Temperature-dependent magnetic sus-ceptibility and thermal degradation for 1 were also studied.The asymmetric unit of compound 1 consists of two crystallographically independent Co(II)ion,two L^(2−)ligand,one 4,4'-bipy ligand,and three lattice water molecules.The 2D triangle networks were linked by the bridging 4,4'-bipy ligand to give rise to a 2-fold interpenetrated 3D architecture.The simplest cyclic motif of the 2D networks is a triangle ring consisting of three Co(II)cations and three L^(2−)ligands.So we can define Co(II)ions as 4-connected nodes and the L^(2−)ligands as 3-connected nodes.Thus,the 3D structure can be described as a 2-fold parallel interpenetrated ins InS 3,4-conn topology. 展开更多
关键词 cobalt-organic framework 2-fold interpenetrated MAGNETISM thermal degradation
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A(3,4)-Connected 3D Heteronuclear Framework with Three Kinds of Discrete Cadmium(Ⅱ) Ions: Synthesis,Crystal Structure and Luminescence Property 被引量:3
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作者 李荣芳 刘新芳 +2 位作者 王玉芳 冯勋 马录芳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第12期1936-1943,共8页
A novel 3D hetero-nuclear framework,namely [K_2Cd_5(Hbptc)_4(H_2O)_(12)·12H_2O]_n(1,H4 bptc = biphenyl-2,3,3?,5?-tetracarboxylic acid),was obtained by hydrothermal reaction. X-ray singlecrystal structur... A novel 3D hetero-nuclear framework,namely [K_2Cd_5(Hbptc)_4(H_2O)_(12)·12H_2O]_n(1,H4 bptc = biphenyl-2,3,3?,5?-tetracarboxylic acid),was obtained by hydrothermal reaction. X-ray singlecrystal structure analysis reveals that polymer 1 crystallizes in orthorhombic,space group Pbcn with a = 26.6152(13),b = 11.7449(5),c = 29.5923(14) ?,V = 9250.3(7) ?~3,C_(64)H_(76)Cd_5K_2O_(56),Mr = 2381.44,Dc = 1.710 g/cm^3,μ(MoK α) = 1.323 mm^(-1),F(000) = 4744,Z = 4,the final R = 0.0668 and wR = 0.1135 for 10613 observed reflections(I 〉 2σ(I)). Polymer 1 displays a 3D network that is built on the unprecedented heterobimetallic [Cd_3Cd_2K] molecular building block with a(3,4)-connected(6·8·8)2(6·6·82·82·126·126) topology which represents a rare 2-fold interpenetrating 3D framework topology network. The luminescence analyses reveal that polymer 1 shows obvious emission at room temperature in the solid state. In addition,it was also characterized by elemental,IR spectra and TG analyses. 展开更多
关键词 hetero-nuclear mental framework Cd/K 2-fold interpenetrating luminescence
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PRESTABILIZATION FOR K_1U~ε OF A-2-FOLD RINGS
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作者 游宏 《Chinese Science Bulletin》 SCIE EI CAS 1992年第5期357-361,共5页
Vaserstein introduced the K<sub>1</sub>-functor for the unitary groups over the associative ring with involution, studied the stabilization of unitary K<sub>1</sub> for some rings with the stab... Vaserstein introduced the K<sub>1</sub>-functor for the unitary groups over the associative ring with involution, studied the stabilization of unitary K<sub>1</sub> for some rings with the stable range condition; and particularly described the prestabilization for K<sub>1</sub>U<sup>ε</sup> of local rings. In this report, we study the prestabilization for K<sub>1</sub>U<sup>ε</sup> of a class of rings satisfying the condition Sr(R) ≤1 which is introduced by Vaserstein and Bass. 展开更多
关键词 K1Uε prestabilization ∧-2-fold RINGS
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1—fold环上GL_2(R)的定义关系 被引量:2
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作者 游宏 《Journal of Mathematical Research and Exposition》 CSCD 1992年第3期385-390,共6页
P.Chon在[3]中给出了局部环及某些离散赋值环上GL_2(R)的定义关系.J.Silvester在[2]中集中讨论了半局部环上线性群的定义关系.某些讨论K_2的文献也从其他角度揭示了线性群的定义关系(见[3]、[4]).在这篇文章中我们将给出1—fold环与一... P.Chon在[3]中给出了局部环及某些离散赋值环上GL_2(R)的定义关系.J.Silvester在[2]中集中讨论了半局部环上线性群的定义关系.某些讨论K_2的文献也从其他角度揭示了线性群的定义关系(见[3]、[4]).在这篇文章中我们将给出1—fold环与一些常见的附加一定条件的1—fold环(如单位稳定环,单位正则环等)上GL_2(R)的定义关系. 展开更多
关键词 1-fold GL2(R) 结合环
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Syntheses, Crystal Structures, and Fluorescence Properties of Two 2D→2D Coordination Polymers Based on the Flexible 4-Substituted Bis(1,2,4-triazole) Ligand
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作者 PENG Yanfen LIU Tianbao WU Qiuyan 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2019年第1期8-14,共7页
Two new 2 D → 2 D zinc(II) coordination polymers, [Zn(btre)0.5(nbdc)(H2 O)]n(1) and {[Zn(btre)0.5(Me Oip)(H2 O)2]·H2 O}n(2)(btre = 1,2-bis(1,2,4-triazol-4-yl)ethane, nbdc=3-nitro-1, 2-benzenedicarboxylate, Me Oi... Two new 2 D → 2 D zinc(II) coordination polymers, [Zn(btre)0.5(nbdc)(H2 O)]n(1) and {[Zn(btre)0.5(Me Oip)(H2 O)2]·H2 O}n(2)(btre = 1,2-bis(1,2,4-triazol-4-yl)ethane, nbdc=3-nitro-1, 2-benzenedicarboxylate, Me Oip=4-methoxybenzene-1, 3-dicarboxylate) were synthesized at room temperature condition and characterized by IR spectra, elemental analyses, single-crystal and powder X-ray diffractions. Three sets of equivalent 2 D(6, 3) networks parallel polycatenated with each other to give a 2 D → 2 D network in 1 and 2. There are strong π-π interactions and hydrogen bonding interactions between adjacent parallel polycatenated 2 D(6, 3) network in 1. Only hydrogen bonding interactions exist in 2. Thermal stabilities and luminescence of 1 and 2 were investigated. 展开更多
关键词 3-fold INTERPENETRATION 1 2-bis(1 2 4-triazol-4-yl)ethane 2D(6 3)network luminescence
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Integrability, multi-soliton and rational solutions, and dynamical analysis for a relativistic Toda lattice system with one perturbation parameter 被引量:1
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作者 Meng-Li Qin Xiao-Yong Wen Cui-Lian Yuan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第6期13-42,共30页
Under investigation in this paper is a relativistic Toda lattice system with one perturbation parameterαabbreviated as RTLαsystem by Suris,which may describe the motions of particles in lattices interacting through ... Under investigation in this paper is a relativistic Toda lattice system with one perturbation parameterαabbreviated as RTLαsystem by Suris,which may describe the motions of particles in lattices interacting through an exponential interaction force.First of all,an integrable lattice hierarchy associated with an RTLαsystem is constructed,from which some relevant integrable properties such as Hamiltonian structures,Liouville integrability and conservation laws are investigated.Secondly,the discrete generalized(m,2 N-m)-fold Darboux transformation is constructed to derive multi-soliton solutions,higher-order rational and semirational solutions,and their mixed solutions of an RTLαsystem.The soliton elastic interactions and details of rational solutions are analyzed via the graphics and asymptotic analysis.Finally,soliton dynamical evolutions are investigated via numerical simulations,showing that a small noise has very little effect on the soliton propagation.These results may provide new insight into nonlinear lattice dynamics described by RTLαsystem. 展开更多
关键词 RTLαsystem Hamiltonian structures discrete generalized(m 2n-m)-fold Darboux transformation soliton and rational solutions asymptotic analysis
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Bifurcations of rough heteroclinic loop with two saddle points 被引量:8
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作者 金银来 朱德明 《Science China Mathematics》 SCIE 2003年第4期459-468,共10页
The bifurcation problems of rough 2-point-loop are studied for the case ρ11>λ11,ρ1/2<λ1/2,ρ11ρ12<λ11λ2, where-ρ1i<0 and λ1i>0 are the pair of principal eigenvalues of unperturbed system at saddle point ... The bifurcation problems of rough 2-point-loop are studied for the case ρ11>λ11,ρ1/2<λ1/2,ρ11ρ12<λ11λ2, where-ρ1i<0 and λ1i>0 are the pair of principal eigenvalues of unperturbed system at saddle point pi, i= 1, 2. Under the transversal and nontwisted conditions, the authors obtain some results of the existence of one 1-periodic orbit, one 1-periodic and one 1-homoclinic loop, two 1-periodic orbits and one 2-fold 1-periodic orbit. Moreover, the bifurcation surfaces and the existence regions are given, and the corresponding bifurcation graph is drawn. 展开更多
关键词 local coordinates POINCARE map 1-homoclinic loop 1-periodic orbit 2-fold 1-periodic orbit bifurcation surface.
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A discrete KdV equation hierarchy:continuous limit, diverse exact solutions and their asymptotic state analysis
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作者 Xue-Ke Liu Xiao-Yong Wen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2022年第6期1-14,共14页
In this paper, a discrete KdV equation that is related to the famous continuous KdV equation is studied. First, an integrable discrete KdV hierarchy is constructed, from which several new discrete KdV equations are ob... In this paper, a discrete KdV equation that is related to the famous continuous KdV equation is studied. First, an integrable discrete KdV hierarchy is constructed, from which several new discrete KdV equations are obtained. Second, we correspond the first several discrete equations of this hierarchy to the continuous KdV equation through the continuous limit. Third, the generalized(m, 2N-m)-fold Darboux transformation of the discrete KdV equation is established based on its known Lax pair. Finally, the diverse exact solutions including soliton solutions, rational solutions and mixed solutions on non-zero seed background are obtained by applying the resulting Darboux transformation, and their asymptotic states and physical properties such as amplitude, velocity, phase and energy are analyzed. At the same time, some soliton solutions are numerically simulated to show their dynamic behaviors. The properties and results obtained in this paper may be helpful to understand some physical phenomena described by KdV equations. 展开更多
关键词 discrete KdV equation hierarchy continuous limit generalized(m 2n-m)-fold Darboux transformation exact solutions asymptotic analysis
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