In the reform process of the rural land property rights system,the incentive mechanism of the rural land property rights system has a crucial impact on the production activities of rural economic entities.Due to the d...In the reform process of the rural land property rights system,the incentive mechanism of the rural land property rights system has a crucial impact on the production activities of rural economic entities.Due to the different rights structures of the property rights system in different social and economic development stages,the land rights and interests enjoyed by rural economic subjects are different,and the degree of incentives for farmers is also different.This difference in incentives affects farmers investment in agricultural production factors,which in turn affects agricultural performance.This paper analyzes the incentive impacts of the structure of rural land property rights on the changes of farmers land rights and agricultural performance since the founding of the People s Republic of China,in order to further deepen the reform of the land system,protect the rights and interests of farmers,promote the modernization of agriculture and rural areas,and explore the realization form and operation mechanism of the rural collective land system in the new era.展开更多
Cyclo[18]carbon has received considerable attention thanks to its novel geometric configuration and special electronic structure.Superalkalis have low ionization energy.Doping a superalkali in cyclo[18]carbon is an ef...Cyclo[18]carbon has received considerable attention thanks to its novel geometric configuration and special electronic structure.Superalkalis have low ionization energy.Doping a superalkali in cyclo[18]carbon is an effective method to improve the optical properties of the system because considerable electron transfer occurs.In this paper,the geometry,bonding properties,electronic structure,absorption spectrum,and nonlinear optical(NLO)properties of superalkaline M_(3)O(M=Li,Na)-doped cyclo[18]carbon were studied by using density functional theory.M_(3)O and the C_(18) rings are not coplanar.The C_(18) ring still exhibits alternating long and short bonds.The charge transfer between M_(3)O and C_(18) forms stable[M_(3)O]+[C_(18)]-ionic complexes.C_(18)M_(3)O(M=Li,Na)shows striking optical nonlinearity,i.e.,their first-and second-order hyperpolarizability(βvec andγ||)increase considerably atλ=1907 nm and 1460 nm.展开更多
In this paper, the microstructure change of one step-draw PET fiber has been studied byvarious methods, such as, Laser Raman Microscope, Wide-angle X-ray, Density-gradient andPolarizing Microscope. The computer has be...In this paper, the microstructure change of one step-draw PET fiber has been studied byvarious methods, such as, Laser Raman Microscope, Wide-angle X-ray, Density-gradient andPolarizing Microscope. The computer has been used to resolve overlapped bands in the Ramanspectra. Then the band changes have been correlated with trans, gauche and stressed trans-conformations indicated by a conformational index. Based on these indices, the relationshipbetween the conformation change of glycol units in the fiber structure and the macromechanicalproperties of fiber is expounded.展开更多
A new Cd(Ⅱ) coordination polymer, namely, [Cd(1,3-bip)(3,5-pdc)]n (1,3-bip = 1,3-bis(imidazol)propane and 3,5-pdc = pyridine-3,5-dicarboxylic acid) has been synthesized under hydrothermal conditions. Compou...A new Cd(Ⅱ) coordination polymer, namely, [Cd(1,3-bip)(3,5-pdc)]n (1,3-bip = 1,3-bis(imidazol)propane and 3,5-pdc = pyridine-3,5-dicarboxylic acid) has been synthesized under hydrothermal conditions. Compound 1 was characterized by infrared spectrum, elemental analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/c with a = 1.40178(7), b = 1.72502(12), c = 1.41635(6) ran, β = 92.653(4)°, V = 3.4212(3) nm3, Z = 4, C16HIsCdNsO4, Mr = 453.73, Dc = 1.762 g/cm3, F(000) = 1808,μ = 1.310 mm1, R = 0.0899 and wR = 0.1945. In compound 1, each 3,5-pdc ligand links three Cd(lI) ions and each Cd(Ⅱ) attaches to bip ligands to form a complicated 2D double-layer structure. In addition, the thermal stability and luminescent property of 1 have been studied in the solid state at room temperature.展开更多
The structure of RE-Ag alloy was observed and analyzed using electron probe. The property changes of the alloy containing two rare earth elements AgLaY during cold forming and the high temperature softening-resistance...The structure of RE-Ag alloy was observed and analyzed using electron probe. The property changes of the alloy containing two rare earth elements AgLaY during cold forming and the high temperature softening-resistance during annealing were studied using Vickers hardness tester. The distribution and action of the rare earth elements in Ag-alloy were also analyzed. Experimental results show that AgLaY alloy has more remarkable work-hardening effect than AgLa and pure silver, and it also has better thermal-resistance. The effects of RE elements, La and Y, on the properties of Ag-alloy are attributable to their symbiotic distribution and complementary function. Because of the common properties of La and Y as RE elements, they have the completely similar distribution in Ag-alloy. At the same time, La and Y make full use of complementary role in the alloy since they belong to different periods in periodic table and have differences in atomic structure and properties.展开更多
A novel zero-dimensional heteronuclear cluster based on N-(phosphonomethyl)imi- no-diacetic acid (H4PMIDA) and Phen (1,10-phenanthroline), [Zn6Co9(PMIDA)6(Phen)6(NO3)4(H2O)6]·2NO3·16H2O, has be...A novel zero-dimensional heteronuclear cluster based on N-(phosphonomethyl)imi- no-diacetic acid (H4PMIDA) and Phen (1,10-phenanthroline), [Zn6Co9(PMIDA)6(Phen)6(NO3)4(H2O)6]·2NO3·16H2O, has been synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectrum, thermal analysis, and single-crystal X-ray diffraction. The isolated 15- nuclearity cluster [Zn6Co9(PMIDA)6(Phen)6(NO3)4(H2O)6]^2+ was constructed by four kinds of ligands, and its charges are balanced by NO3^–. Each isolated cluster is further extended into a 3D supramolecular network through π???π interaction and C–H…O hydrogen bonds. Moreover, the solid-state fluorescent property of this complex has also been investigated at room temperature.展开更多
A new quaternary rare-earth sulfide, Cs0.75(6)Er443(5)In3.32(6)S12 (1), is discovered by high temperature solid state reactions with a slight excess of CsCI flux. The structure is characterized by single-cryst...A new quaternary rare-earth sulfide, Cs0.75(6)Er443(5)In3.32(6)S12 (1), is discovered by high temperature solid state reactions with a slight excess of CsCI flux. The structure is characterized by single-crystal X-ray diffraction data, while crystallizes in hexagonal space group P63/m (No. 176) with a = 12.0329(6), c = 3.8693(5)A, V= 485.18(7) A3, Z = 1, Mr = 1606.57, Dc = 5.499 g/cm3,μ = 25.457 mm-1, F(000) = 752, the final R = 0.0337 and wR = 0.0904 for 328 observed reflections with I 〉 2σ(I). Its structure features a three-dimensional framework with hexagonal channels that are centered by Cs cations. Such channels are formed by double chains of edge-sharing M(1)S6 (M(1) = Er(1)/In(1)) octahedra and single chains of Er(2)S6 triprism interconnected by corner-sharing. The syntheses, single-crystal analyses, optical band gap and magnetic property are reported.展开更多
A new coordination framework, {[Zn(L1)(5-nipc)]·H2O}n(1, L1 = 4ˊ-(4-pyridyl)-4,2ˊ:6ˊ,4ˊˊ-terpyridine, 5-nipc = 5-nitroisophthalic acid), has been prepared under hydrothermal conditions, and determin...A new coordination framework, {[Zn(L1)(5-nipc)]·H2O}n(1, L1 = 4ˊ-(4-pyridyl)-4,2ˊ:6ˊ,4ˊˊ-terpyridine, 5-nipc = 5-nitroisophthalic acid), has been prepared under hydrothermal conditions, and determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR and powder X-ray diffraction. Complex 1 crystallizes in monoclinic, space group C2/c with a = 29.983(9), b = 13.709(3), c = 14.391(3)A, β = 114.93(4)°, V = 5364(2) A3, Dc = 1.493 g/cm^3, C28H19N5O7 Zn, Mr = 602.85, F(000) = 2464, μ(Mo Kα) = 0.972 mm^-1, Z = 8, R = 0.0935 and w R = 0.1509 for 4724 observed reflections(I 〉 2σ(I)). The structure of 1 exhibits a three-dimensional(3D) network with a layer-pillar structure. The fluorescence property of 1 is also investigated.展开更多
The reaction of flexible bis(imidazole) ligand and 1,2-bis(imidazol-l'-yl)methane (bimm) with Co(Ⅱ) salt under ionothermal method resulted in the formation of a new coordination polymer {[Co(bimm)3]·...The reaction of flexible bis(imidazole) ligand and 1,2-bis(imidazol-l'-yl)methane (bimm) with Co(Ⅱ) salt under ionothermal method resulted in the formation of a new coordination polymer {[Co(bimm)3]·(PF6)2}n (1). X-ray single-crystal diffraction determination reveals that 1 crystallizes in the triclinic Pi space group, with α = 8.647(6), b = 12.092(9), c = 14.967(1 l) A, α = 88.912(8), β = 81.199(8), ), = 89.395(8)°, V= 1546 (2) A3, Z = 2, Mr = 793.39, Dc= 1.704 Mg/m3,μ = 0.768 mm-1 F(000) = 798, the final R = 0.0626 and wR = 0.1634 for 4319 observed reflections with I〉 2σ(I). In compound 1, the Co(lI) ion is connected to another Co(ll) by two bimm ligands to form 1D double chains which are further linked by bimm ligands to form a 2D wavelike layer. Topologically, the structure of 1 represents a uninodal 2D 4-connected sq1/Shubnikov tetragonal plane net. Moreover, thermogravimetric analyses and photocatalytic property for 1 have also been investigated.展开更多
A new ternary neodymium zirconium sulfide Nd_2ZrS_5 was synthesized by high-temperature solid-state reaction and structurally characterized by single-crystal X-ray diffraction. It crystallizes in the orthorhombic spac...A new ternary neodymium zirconium sulfide Nd_2ZrS_5 was synthesized by high-temperature solid-state reaction and structurally characterized by single-crystal X-ray diffraction. It crystallizes in the orthorhombic space group Pnma(No. 62) belonging to the Y_2HfS_5 structure-type with a = 11.461(4), b = 8.009(3), c = 7.315(3) A, Z = 2 and V = 671.5(4)A3. Its structure features NdS_8 and ZrS_7 polyhedra-constructed a 3-D network. The data of magnetic susceptibility indicate its antiferromagnetic-like behavior without magnetic order down to 2 K.展开更多
A Ti-BN complex cathode is made from Ti and h-BN powders by the powder metallurgy technology, and TiBN coating is obtained by plasma immersion ion implantation and deposition with this Ti-BN composite cathode. The TiB...A Ti-BN complex cathode is made from Ti and h-BN powders by the powder metallurgy technology, and TiBN coating is obtained by plasma immersion ion implantation and deposition with this Ti-BN composite cathode. The TiBN coating shows a self-forming multilayered nanocomposite structure while with relative uniform elemental distributions. High resolution transmission electron microscopy images reveal that the multilayered structure is derived from different grain sizes in the nanocomposite. Due to the existence of h-BN phase, the friction coefficient of the coating is about 0.25.展开更多
Under aircondition,theinsitu TiCP/ Fecompositeshavebeen fabricated by a reactivecast ing route usingtheinexpensiveraw materials. The microstructuresofthecompositehavebeen studied by X ray diffraction,image analyz...Under aircondition,theinsitu TiCP/ Fecompositeshavebeen fabricated by a reactivecast ing route usingtheinexpensiveraw materials. The microstructuresofthecompositehavebeen studied by X ray diffraction,image analyzer and analyticalelectron microscopy. The me chanicalpropertiesand abrasive wearresistanceofboththeas castcompositeandthequenched composite havebeen measured. Theresultsshow thattheinsitu TiCparticles with a average sizeof 4 51μm exhibit a homogenous distribution inthe matrix, and an excellentinterface bonding between the particle and the matrix is achieved. As above microstructure features, thecomposite,especiallythequenched composite, hashigher mechanicalpropertiesand betterwear resistance,compared with high Cr whitecastiron.展开更多
The title complex [Sr3(pda)2(Hpda)2(H2O)2]n·2nH2O(H2pda = pyridine-2,6-dicar- boxylic acid) has been prepared under solvothermal conditions. It has been characterized by X-ray single-crystal diffraction, ...The title complex [Sr3(pda)2(Hpda)2(H2O)2]n·2nH2O(H2pda = pyridine-2,6-dicar- boxylic acid) has been prepared under solvothermal conditions. It has been characterized by X-ray single-crystal diffraction, IR and elemental analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 10.3795(8), b = 9.2225(7), c = 18.5726(14) , β = 104.377(2)o, V = 1722.2(2) 3, C28H22N4O20Sr3, Mr = 997.36, Z = 2, Dc = 1.923 g/cm3, μ = 4.722 mm-1, F(000) = 984, the final R = 0.0269 and wR = 0.0538. This complex possesses a 3-D structure which is constructed from 1-D chain motifs linked by carboxylate groups. The luminescent property of the title complex has been investigated.展开更多
A novel zinc complex [Zn(BIB)(bdc)]n(1, BIB = 1,3-bis(imidazol-1-yl)benzene, bdc = 1,3-benzenedicarboxylate) has been synthesized in solvothermal conditions. The title complex was characterized by elemental an...A novel zinc complex [Zn(BIB)(bdc)]n(1, BIB = 1,3-bis(imidazol-1-yl)benzene, bdc = 1,3-benzenedicarboxylate) has been synthesized in solvothermal conditions. The title complex was characterized by elemental analysis, IR spectra, thermal analysis, single-crystal and powder X-ray diffraction. The result proved that the alliance of BIB and aromatic carboxylic acids is good for the diversity of getatable structure. Complex 1 crystallizes in the monoclinic system of P2/c space group with a = 11.5591(10), b = 9.6239(8), c = 33.727(3)A, β = 103.816(3)°, V = 3643.4(5) A^3, Z = 8, μ = 1.385 mm^-1, F(000) = 1792, Dc = 1.603 g/cm^3 and Mr = 439.72 g/mol. Additionally, luminescent properties of complex 1 are also investigated and it shows good fluorescence.展开更多
A new complex [Co(4,4'-bpy)2(H2O)2(4-FBA)2]·(4,4'-bpy)(1) has been hydro-thermally synthesized using cobalt,4,4'-bipyridyl(4,4'-bpy) and 4-fluorobenzoic acid(4-HFBA),and characterized by thermal...A new complex [Co(4,4'-bpy)2(H2O)2(4-FBA)2]·(4,4'-bpy)(1) has been hydro-thermally synthesized using cobalt,4,4'-bipyridyl(4,4'-bpy) and 4-fluorobenzoic acid(4-HFBA),and characterized by thermal analysis,single-crystal X-ray diffraction and magnetic property.The complex crystallizes in the triclinic system,space group P,Z = 1.Crystal data:C54H44CoF2N8O6,Mr = 997.90,a = 9.134(2),b = 11.555(2),c = 12.867(3) ,α = 66.02(3),β = 77.96(3),= 73.11(3)°,V = 1180.9(4) 3,Dc = 1.403 g/cm3,μ(MoKα) = 0.433 mm-1,F(000) = 517,the final R = 0.0633 and wR = 0.1171 for 2152 observed reflections(I 〉 2σ(I)).The title complex is assembled into 1D supramolecular chains parallel to [001] based on the adjacent molecular ··· stacking interactions and hydrogen bonds.The variable temperature magnetic measurements show a weak ferromagnetic behavior over 300-160 K followed by antiferromagnetic behavior below 160 K for the title complex.展开更多
A new Cd(Ⅱ) complex([Cd(H2PIDC)2]n) with singly deprotonated 2-propyl-imidazole-4,5-dicarboxylate as bridging ligand was synthesized and characterized by X-ray diffraction method.Crystal data:monoclinic,space ...A new Cd(Ⅱ) complex([Cd(H2PIDC)2]n) with singly deprotonated 2-propyl-imidazole-4,5-dicarboxylate as bridging ligand was synthesized and characterized by X-ray diffraction method.Crystal data:monoclinic,space group P21/c,with a=8.2547(11),b=10.7071(15),c=13.9131(14)A,β=126.164(5)o,V=992.8(2)A^3,C16H18N4O8Cd,Mr=506.74,Z=2,Dc=1.695g/cm^3,F(000)=508,μ=1.151 mm^-1,R=0.0296 and wR=0.0812 for 1581 observed reflections.Singly deprotonated ligands(H2PIDC-) act as μ3-bridge and join the Cd(Ⅱ) atoms into a 2-D layer structure.The 2-D layers are further linked by intermolecular hydrogen bonds into a 3D network.The luminescent property of the complex was also investigated.展开更多
Making use of N-P-acetamidobenzenesulfonyl-glycine acid (abbreviated as abglyH2),two transitional metal complexes [Zn(abglyH)(phen)2]ClO4·H2O (1) and Co(abglyH)2(bipy)2(H2O)2 (2) (phen = 1,10-phe...Making use of N-P-acetamidobenzenesulfonyl-glycine acid (abbreviated as abglyH2),two transitional metal complexes [Zn(abglyH)(phen)2]ClO4·H2O (1) and Co(abglyH)2(bipy)2(H2O)2 (2) (phen = 1,10-phenanthroline,bipy = 4,4'-bipyridine) have been synthesized under mild conditions and characterized by IR,elemental analysis and X-ray diffraction analysis. Complex 1 is a monomeric compound which is further assembled by intermolecular hydrogen bonds and π-π interaction into a 2-D supramolecular network. Complex 2 is also a monomeric compound and further connected by intermolecular hydrogen bonds to form a 2-D supramolecular network. Fluorescent analysis shows that complex 1 has an emissive maximum at 364 nm in the solution state at room temperature.展开更多
The synthesis,structure and luminescent property of a tetranuclear gold(Ⅰ)complex with doubly bridging diethyldithiocarbamate(Et2dtc)and 1,1-bis(diphenylphosphino)ethene((Ph2P)2C=CH2)are described.The compl...The synthesis,structure and luminescent property of a tetranuclear gold(Ⅰ)complex with doubly bridging diethyldithiocarbamate(Et2dtc)and 1,1-bis(diphenylphosphino)ethene((Ph2P)2C=CH2)are described.The complex crystallizes in monoclinic space group C2/c with a=26.785(7),b=25.654(6),c=12.277(3)A,β=106.879(5)°,V=8073(4)A^3,Z=8,C31H32Au2F6NO3P2S2Sb,Mr=1222.32,Dc=2.011 g/cm^3,F(000)=4592,Rint=0.0529,T=293(2)K,μ=8.157 mm^(-1),the final R=0.0464 and wR=0.1444 for 5804 observed reflections with I〉2σ(Ⅰ).The intramolecular and intermolecular Au¨Au distances are 2.8670(9)and 3.2367(9)A,respectively.Weak emission appears at 517 nm at room temperature in the solid state.展开更多
A novel mononuclear copper(Ⅱ) complex [Cu(bbmc)Cl_2]·DMF,where bbmc is 1,1-bis(1H-benzoimidazol-2-ylmethyl)cyclohexane,was synthesized and characterized by X-ray single-crystal structure analysis.The compl...A novel mononuclear copper(Ⅱ) complex [Cu(bbmc)Cl_2]·DMF,where bbmc is 1,1-bis(1H-benzoimidazol-2-ylmethyl)cyclohexane,was synthesized and characterized by X-ray single-crystal structure analysis.The complex crystallizes in triclinic,space group P1 with a = 9.1088(5),b = 11.0075(4),c = 14.2326(6)A,α = 97.188(3),β = 96.394(4),γ = 111.430(4)°,V = 1298.73(10) A^3,Z = 2,D_c = 1.409 g/cm^3,μ(Mo Kα) = 1.074 mm^-1,F(000) = 572,S = 1.078,R = 0.0381 and w R = 0.0876 for 5593 observed reflections with I 〉 2σ(I).The central Cu(Ⅱ) ion adopts a distorted tetrahedral geometry coordinated by two nitrogen atoms of the ligand and two chloride ions.The complex showed its thermal decomposition temperature up to 226 ℃ and exhibited an irreversible one-electron transfer process involving Cu^Ⅱ/Cu^I couple.展开更多
Permeability is a key parameter for coalbed methane development.Although the absolute permeability of coal has been extensively studied,wettability and pore structure properties continue to challenge the microscopic d...Permeability is a key parameter for coalbed methane development.Although the absolute permeability of coal has been extensively studied,wettability and pore structure properties continue to challenge the microscopic description of water-gas flow in coal.For this purpose,we reconstructed the microstructures of low-rank coal using micro-computed tomography(micro-CT)images.Pore geometry and pore-throat parameters are introduced to establish a relationship with absolute permeability.A dual-porosity pore network model is developed to study water-gas displacement under different wetting and pore structure properties.Results show that absolute permeability is significantly affected by pore geometry and can be described using a binary quadratic function of porosity and fractal dimension.Water-gas relative permeability varies significantly and the residual gas saturation is lower;the crossover saturation first decreased and then increased with increasing porosity under hydrophobic conditions.While the water relative permeability is lower and a certain amount of gas is trapped in complex pore-throat networks;the crossover saturation is higher under hydrophilic conditions.Models with large percolating porosity and well-developed pore networks have high displacement efficiency due to low capillary resistance and avoidance of trapping.This work provides a systematic description of absolute permeability and water-gas relative permeability in coal microstructure for enhanced gas recovery.展开更多
基金Supported by National Natural Science Foundation of China(41771565)Henan Provincial Government Decision-Making Research Bidding Project(2017B189).
文摘In the reform process of the rural land property rights system,the incentive mechanism of the rural land property rights system has a crucial impact on the production activities of rural economic entities.Due to the different rights structures of the property rights system in different social and economic development stages,the land rights and interests enjoyed by rural economic subjects are different,and the degree of incentives for farmers is also different.This difference in incentives affects farmers investment in agricultural production factors,which in turn affects agricultural performance.This paper analyzes the incentive impacts of the structure of rural land property rights on the changes of farmers land rights and agricultural performance since the founding of the People s Republic of China,in order to further deepen the reform of the land system,protect the rights and interests of farmers,promote the modernization of agriculture and rural areas,and explore the realization form and operation mechanism of the rural collective land system in the new era.
基金Project supported by the Natural Science Foundation of Anhui Province(Grant No.1908085MA12)the National Natural Science Foundation of China(Grant No.21703222)。
文摘Cyclo[18]carbon has received considerable attention thanks to its novel geometric configuration and special electronic structure.Superalkalis have low ionization energy.Doping a superalkali in cyclo[18]carbon is an effective method to improve the optical properties of the system because considerable electron transfer occurs.In this paper,the geometry,bonding properties,electronic structure,absorption spectrum,and nonlinear optical(NLO)properties of superalkaline M_(3)O(M=Li,Na)-doped cyclo[18]carbon were studied by using density functional theory.M_(3)O and the C_(18) rings are not coplanar.The C_(18) ring still exhibits alternating long and short bonds.The charge transfer between M_(3)O and C_(18) forms stable[M_(3)O]+[C_(18)]-ionic complexes.C_(18)M_(3)O(M=Li,Na)shows striking optical nonlinearity,i.e.,their first-and second-order hyperpolarizability(βvec andγ||)increase considerably atλ=1907 nm and 1460 nm.
文摘In this paper, the microstructure change of one step-draw PET fiber has been studied byvarious methods, such as, Laser Raman Microscope, Wide-angle X-ray, Density-gradient andPolarizing Microscope. The computer has been used to resolve overlapped bands in the Ramanspectra. Then the band changes have been correlated with trans, gauche and stressed trans-conformations indicated by a conformational index. Based on these indices, the relationshipbetween the conformation change of glycol units in the fiber structure and the macromechanicalproperties of fiber is expounded.
基金Supported by the National Natural Science Foundation of China(No.21373132)the Science Foundation of Education Department of Shaanxi Provincial Government(No.12JK0637)
文摘A new Cd(Ⅱ) coordination polymer, namely, [Cd(1,3-bip)(3,5-pdc)]n (1,3-bip = 1,3-bis(imidazol)propane and 3,5-pdc = pyridine-3,5-dicarboxylic acid) has been synthesized under hydrothermal conditions. Compound 1 was characterized by infrared spectrum, elemental analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/c with a = 1.40178(7), b = 1.72502(12), c = 1.41635(6) ran, β = 92.653(4)°, V = 3.4212(3) nm3, Z = 4, C16HIsCdNsO4, Mr = 453.73, Dc = 1.762 g/cm3, F(000) = 1808,μ = 1.310 mm1, R = 0.0899 and wR = 0.1945. In compound 1, each 3,5-pdc ligand links three Cd(lI) ions and each Cd(Ⅱ) attaches to bip ligands to form a complicated 2D double-layer structure. In addition, the thermal stability and luminescent property of 1 have been studied in the solid state at room temperature.
文摘The structure of RE-Ag alloy was observed and analyzed using electron probe. The property changes of the alloy containing two rare earth elements AgLaY during cold forming and the high temperature softening-resistance during annealing were studied using Vickers hardness tester. The distribution and action of the rare earth elements in Ag-alloy were also analyzed. Experimental results show that AgLaY alloy has more remarkable work-hardening effect than AgLa and pure silver, and it also has better thermal-resistance. The effects of RE elements, La and Y, on the properties of Ag-alloy are attributable to their symbiotic distribution and complementary function. Because of the common properties of La and Y as RE elements, they have the completely similar distribution in Ag-alloy. At the same time, La and Y make full use of complementary role in the alloy since they belong to different periods in periodic table and have differences in atomic structure and properties.
基金Supported by the Youth Fund Project of Shaanxi University of Chinese Medicine(No.2015Qn22)the National Youth Natural Science Foundation of China(No.21603133)the Science Foundation of Shaanxi University of Technology(No.SLGKY15-36)
文摘A novel zero-dimensional heteronuclear cluster based on N-(phosphonomethyl)imi- no-diacetic acid (H4PMIDA) and Phen (1,10-phenanthroline), [Zn6Co9(PMIDA)6(Phen)6(NO3)4(H2O)6]·2NO3·16H2O, has been synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectrum, thermal analysis, and single-crystal X-ray diffraction. The isolated 15- nuclearity cluster [Zn6Co9(PMIDA)6(Phen)6(NO3)4(H2O)6]^2+ was constructed by four kinds of ligands, and its charges are balanced by NO3^–. Each isolated cluster is further extended into a 3D supramolecular network through π???π interaction and C–H…O hydrogen bonds. Moreover, the solid-state fluorescent property of this complex has also been investigated at room temperature.
基金Supported by the National Natural Science Foundation of China(90922021,20773130,20733003,20803080,20973175)"Knowledge Innovation Program of the Chinese Academy of Sciences"(KJCX2-YW-H20,CXJJ-11-M71)
文摘A new quaternary rare-earth sulfide, Cs0.75(6)Er443(5)In3.32(6)S12 (1), is discovered by high temperature solid state reactions with a slight excess of CsCI flux. The structure is characterized by single-crystal X-ray diffraction data, while crystallizes in hexagonal space group P63/m (No. 176) with a = 12.0329(6), c = 3.8693(5)A, V= 485.18(7) A3, Z = 1, Mr = 1606.57, Dc = 5.499 g/cm3,μ = 25.457 mm-1, F(000) = 752, the final R = 0.0337 and wR = 0.0904 for 328 observed reflections with I 〉 2σ(I). Its structure features a three-dimensional framework with hexagonal channels that are centered by Cs cations. Such channels are formed by double chains of edge-sharing M(1)S6 (M(1) = Er(1)/In(1)) octahedra and single chains of Er(2)S6 triprism interconnected by corner-sharing. The syntheses, single-crystal analyses, optical band gap and magnetic property are reported.
基金supported by the Startup Foundation for Doctors of Jinzhong University
文摘A new coordination framework, {[Zn(L1)(5-nipc)]·H2O}n(1, L1 = 4ˊ-(4-pyridyl)-4,2ˊ:6ˊ,4ˊˊ-terpyridine, 5-nipc = 5-nitroisophthalic acid), has been prepared under hydrothermal conditions, and determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR and powder X-ray diffraction. Complex 1 crystallizes in monoclinic, space group C2/c with a = 29.983(9), b = 13.709(3), c = 14.391(3)A, β = 114.93(4)°, V = 5364(2) A3, Dc = 1.493 g/cm^3, C28H19N5O7 Zn, Mr = 602.85, F(000) = 2464, μ(Mo Kα) = 0.972 mm^-1, Z = 8, R = 0.0935 and w R = 0.1509 for 4724 observed reflections(I 〉 2σ(I)). The structure of 1 exhibits a three-dimensional(3D) network with a layer-pillar structure. The fluorescence property of 1 is also investigated.
基金supported by the Natural Science Foundation of Henan Province(132300410326)the Foundation of the Education Department of Henan Province(13A150801 and 14A150040)
文摘The reaction of flexible bis(imidazole) ligand and 1,2-bis(imidazol-l'-yl)methane (bimm) with Co(Ⅱ) salt under ionothermal method resulted in the formation of a new coordination polymer {[Co(bimm)3]·(PF6)2}n (1). X-ray single-crystal diffraction determination reveals that 1 crystallizes in the triclinic Pi space group, with α = 8.647(6), b = 12.092(9), c = 14.967(1 l) A, α = 88.912(8), β = 81.199(8), ), = 89.395(8)°, V= 1546 (2) A3, Z = 2, Mr = 793.39, Dc= 1.704 Mg/m3,μ = 0.768 mm-1 F(000) = 798, the final R = 0.0626 and wR = 0.1634 for 4319 observed reflections with I〉 2σ(I). In compound 1, the Co(lI) ion is connected to another Co(ll) by two bimm ligands to form 1D double chains which are further linked by bimm ligands to form a 2D wavelike layer. Topologically, the structure of 1 represents a uninodal 2D 4-connected sq1/Shubnikov tetragonal plane net. Moreover, thermogravimetric analyses and photocatalytic property for 1 have also been investigated.
基金Supported by Higher Education Science Foundation of Jiangsu Province(No.15KJB150031)State Key Laboratory of Structural Chemistry Fund(No.20150009)+1 种基金Yangzhou University for the start-up grantthe Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘A new ternary neodymium zirconium sulfide Nd_2ZrS_5 was synthesized by high-temperature solid-state reaction and structurally characterized by single-crystal X-ray diffraction. It crystallizes in the orthorhombic space group Pnma(No. 62) belonging to the Y_2HfS_5 structure-type with a = 11.461(4), b = 8.009(3), c = 7.315(3) A, Z = 2 and V = 671.5(4)A3. Its structure features NdS_8 and ZrS_7 polyhedra-constructed a 3-D network. The data of magnetic susceptibility indicate its antiferromagnetic-like behavior without magnetic order down to 2 K.
基金Supported by the Fund of National Key Laboratory of High Power Microwave Technology under Grant No 2014-763.xy.kthe National Natural Science Foundation of China under Grant No 21573054the Joint Funds Key Project of the National Natural Science Foundation of China under Grant No U1537214
文摘A Ti-BN complex cathode is made from Ti and h-BN powders by the powder metallurgy technology, and TiBN coating is obtained by plasma immersion ion implantation and deposition with this Ti-BN composite cathode. The TiBN coating shows a self-forming multilayered nanocomposite structure while with relative uniform elemental distributions. High resolution transmission electron microscopy images reveal that the multilayered structure is derived from different grain sizes in the nanocomposite. Due to the existence of h-BN phase, the friction coefficient of the coating is about 0.25.
文摘Under aircondition,theinsitu TiCP/ Fecompositeshavebeen fabricated by a reactivecast ing route usingtheinexpensiveraw materials. The microstructuresofthecompositehavebeen studied by X ray diffraction,image analyzer and analyticalelectron microscopy. The me chanicalpropertiesand abrasive wearresistanceofboththeas castcompositeandthequenched composite havebeen measured. Theresultsshow thattheinsitu TiCparticles with a average sizeof 4 51μm exhibit a homogenous distribution inthe matrix, and an excellentinterface bonding between the particle and the matrix is achieved. As above microstructure features, thecomposite,especiallythequenched composite, hashigher mechanicalpropertiesand betterwear resistance,compared with high Cr whitecastiron.
基金Supported by the National Natural Science Foundation of China(21272167 and 21201127)a project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institution,Graduate Education Innovation Project in Jiangsu Province(CXZZ12_0808)+1 种基金Qinghai Science&Technology Department of China(2011-G-208 and 2011-Z-722)KLSLRC(KLSLRC-KF-13-HX-1)
文摘The title complex [Sr3(pda)2(Hpda)2(H2O)2]n·2nH2O(H2pda = pyridine-2,6-dicar- boxylic acid) has been prepared under solvothermal conditions. It has been characterized by X-ray single-crystal diffraction, IR and elemental analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 10.3795(8), b = 9.2225(7), c = 18.5726(14) , β = 104.377(2)o, V = 1722.2(2) 3, C28H22N4O20Sr3, Mr = 997.36, Z = 2, Dc = 1.923 g/cm3, μ = 4.722 mm-1, F(000) = 984, the final R = 0.0269 and wR = 0.0538. This complex possesses a 3-D structure which is constructed from 1-D chain motifs linked by carboxylate groups. The luminescent property of the title complex has been investigated.
基金supported by grants from Provincial Key Projects of Anhui Natural Science Research in Universities(No.KJ2015A203)the Natural Science Foundation of Anhui Province(No.1408085MB40)Projects of Anhui Key Laboratory of Spin Electron and Nanomaterials,Suzhou University(No.2014YKF51)
文摘A novel zinc complex [Zn(BIB)(bdc)]n(1, BIB = 1,3-bis(imidazol-1-yl)benzene, bdc = 1,3-benzenedicarboxylate) has been synthesized in solvothermal conditions. The title complex was characterized by elemental analysis, IR spectra, thermal analysis, single-crystal and powder X-ray diffraction. The result proved that the alliance of BIB and aromatic carboxylic acids is good for the diversity of getatable structure. Complex 1 crystallizes in the monoclinic system of P2/c space group with a = 11.5591(10), b = 9.6239(8), c = 33.727(3)A, β = 103.816(3)°, V = 3643.4(5) A^3, Z = 8, μ = 1.385 mm^-1, F(000) = 1792, Dc = 1.603 g/cm^3 and Mr = 439.72 g/mol. Additionally, luminescent properties of complex 1 are also investigated and it shows good fluorescence.
文摘A new complex [Co(4,4'-bpy)2(H2O)2(4-FBA)2]·(4,4'-bpy)(1) has been hydro-thermally synthesized using cobalt,4,4'-bipyridyl(4,4'-bpy) and 4-fluorobenzoic acid(4-HFBA),and characterized by thermal analysis,single-crystal X-ray diffraction and magnetic property.The complex crystallizes in the triclinic system,space group P,Z = 1.Crystal data:C54H44CoF2N8O6,Mr = 997.90,a = 9.134(2),b = 11.555(2),c = 12.867(3) ,α = 66.02(3),β = 77.96(3),= 73.11(3)°,V = 1180.9(4) 3,Dc = 1.403 g/cm3,μ(MoKα) = 0.433 mm-1,F(000) = 517,the final R = 0.0633 and wR = 0.1171 for 2152 observed reflections(I 〉 2σ(I)).The title complex is assembled into 1D supramolecular chains parallel to [001] based on the adjacent molecular ··· stacking interactions and hydrogen bonds.The variable temperature magnetic measurements show a weak ferromagnetic behavior over 300-160 K followed by antiferromagnetic behavior below 160 K for the title complex.
基金supported by the National Natural Science Foundation of China (No 20771054)the Foundation of Education Committee of Henan Province (2006150017)
文摘A new Cd(Ⅱ) complex([Cd(H2PIDC)2]n) with singly deprotonated 2-propyl-imidazole-4,5-dicarboxylate as bridging ligand was synthesized and characterized by X-ray diffraction method.Crystal data:monoclinic,space group P21/c,with a=8.2547(11),b=10.7071(15),c=13.9131(14)A,β=126.164(5)o,V=992.8(2)A^3,C16H18N4O8Cd,Mr=506.74,Z=2,Dc=1.695g/cm^3,F(000)=508,μ=1.151 mm^-1,R=0.0296 and wR=0.0812 for 1581 observed reflections.Singly deprotonated ligands(H2PIDC-) act as μ3-bridge and join the Cd(Ⅱ) atoms into a 2-D layer structure.The 2-D layers are further linked by intermolecular hydrogen bonds into a 3D network.The luminescent property of the complex was also investigated.
基金supported by the National Natural Science Foundation of China (Nos. 20771054 and 20471026) Henan Tackle Key Problem of Science and Technology (Nos. 072102270030 and 072102270034)
文摘Making use of N-P-acetamidobenzenesulfonyl-glycine acid (abbreviated as abglyH2),two transitional metal complexes [Zn(abglyH)(phen)2]ClO4·H2O (1) and Co(abglyH)2(bipy)2(H2O)2 (2) (phen = 1,10-phenanthroline,bipy = 4,4'-bipyridine) have been synthesized under mild conditions and characterized by IR,elemental analysis and X-ray diffraction analysis. Complex 1 is a monomeric compound which is further assembled by intermolecular hydrogen bonds and π-π interaction into a 2-D supramolecular network. Complex 2 is also a monomeric compound and further connected by intermolecular hydrogen bonds to form a 2-D supramolecular network. Fluorescent analysis shows that complex 1 has an emissive maximum at 364 nm in the solution state at room temperature.
基金financial supports from the NNSFC(20931006,U0934003,and 91122006)the NSF of Fujian Province(2011J01065)
文摘The synthesis,structure and luminescent property of a tetranuclear gold(Ⅰ)complex with doubly bridging diethyldithiocarbamate(Et2dtc)and 1,1-bis(diphenylphosphino)ethene((Ph2P)2C=CH2)are described.The complex crystallizes in monoclinic space group C2/c with a=26.785(7),b=25.654(6),c=12.277(3)A,β=106.879(5)°,V=8073(4)A^3,Z=8,C31H32Au2F6NO3P2S2Sb,Mr=1222.32,Dc=2.011 g/cm^3,F(000)=4592,Rint=0.0529,T=293(2)K,μ=8.157 mm^(-1),the final R=0.0464 and wR=0.1444 for 5804 observed reflections with I〉2σ(Ⅰ).The intramolecular and intermolecular Au¨Au distances are 2.8670(9)and 3.2367(9)A,respectively.Weak emission appears at 517 nm at room temperature in the solid state.
基金Financially supported from National Natural Science Foundation of China(No.21403191)Natural Science Foundation of Guangdong Province(Nos.2014A030307010 and 2015A0303010406)+2 种基金Special funds for public welfare research and capacity building in Guangdong Province(No.2015A010105031)Zhanjiang Science Technology Project(No.2013B01054)Lingnan Normal University Science Research Foundation(Nos.L1301 and LZL1504)
文摘A novel mononuclear copper(Ⅱ) complex [Cu(bbmc)Cl_2]·DMF,where bbmc is 1,1-bis(1H-benzoimidazol-2-ylmethyl)cyclohexane,was synthesized and characterized by X-ray single-crystal structure analysis.The complex crystallizes in triclinic,space group P1 with a = 9.1088(5),b = 11.0075(4),c = 14.2326(6)A,α = 97.188(3),β = 96.394(4),γ = 111.430(4)°,V = 1298.73(10) A^3,Z = 2,D_c = 1.409 g/cm^3,μ(Mo Kα) = 1.074 mm^-1,F(000) = 572,S = 1.078,R = 0.0381 and w R = 0.0876 for 5593 observed reflections with I 〉 2σ(I).The central Cu(Ⅱ) ion adopts a distorted tetrahedral geometry coordinated by two nitrogen atoms of the ligand and two chloride ions.The complex showed its thermal decomposition temperature up to 226 ℃ and exhibited an irreversible one-electron transfer process involving Cu^Ⅱ/Cu^I couple.
基金the National Natural Science Foundation of China(Nos.51934004,51974176)the Natural Science Foundation for Distinguished Young Scholars of Shandong Province(No.ZR2020JQ22)+1 种基金the Youth Science and Technology Innovation of Shandong Province(No.2019KJH006)the Special Funds for Taishan Scholar Project(No.TS20190935).
文摘Permeability is a key parameter for coalbed methane development.Although the absolute permeability of coal has been extensively studied,wettability and pore structure properties continue to challenge the microscopic description of water-gas flow in coal.For this purpose,we reconstructed the microstructures of low-rank coal using micro-computed tomography(micro-CT)images.Pore geometry and pore-throat parameters are introduced to establish a relationship with absolute permeability.A dual-porosity pore network model is developed to study water-gas displacement under different wetting and pore structure properties.Results show that absolute permeability is significantly affected by pore geometry and can be described using a binary quadratic function of porosity and fractal dimension.Water-gas relative permeability varies significantly and the residual gas saturation is lower;the crossover saturation first decreased and then increased with increasing porosity under hydrophobic conditions.While the water relative permeability is lower and a certain amount of gas is trapped in complex pore-throat networks;the crossover saturation is higher under hydrophilic conditions.Models with large percolating porosity and well-developed pore networks have high displacement efficiency due to low capillary resistance and avoidance of trapping.This work provides a systematic description of absolute permeability and water-gas relative permeability in coal microstructure for enhanced gas recovery.