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Mixed-dimensional SWCNT–MoS2 films demonstrate a strong photothermoelectric (PTE) effect for constructing a high-performance PET photodetector with polarization sensitivity.

Three kinds of cellulose nanocrystals (CNCs) were added into waterborne polyurethane (WPU), and nanocomposite films were prepared by solution casting method. The influence of different ionic function groups on microstructure and properties of composite films was investigated, and interaction mechanism between these two components was analyzed. Results show that thermal stability of these composite films are improved by 15℃. Compared with sulfated CNCs （SCNCs） and TEMPO oxidized CNCs (TOCNCs), FE-SEM results prove that cationized CNCs (CaCNCs) have better dispersion in composite films. In addition, fracture surface did not display large cavities, which indicates the interface binding force between WPU and CaCNCs is stronger. The tensile strength and fracture work of CaCNC/WPU composite film increase by 11.9% and by 8.4%, respectively. The oxygen permeability of CaCNC/WPU composite film is the lowest in these composite films, which is 5.00 cm3•cm (cm2•s•Pa)-1. Water vapor permeability of composite films may have a close positive correlation with their hygroscopicity. In all, composite film with CaCNCs has optimal strength, toughness, light transmittance and oxygen barrier properties. There may be opposite ion attraction superimposed hydrogen bond between CaCNCs and WPU in the composite film. The composite films are expected to have applications in food packaging, furniture coatings and biomedical applications.

C21H24N2O3, orthorhombic, P212121 (no. 19), a = 9.7186(12) Å, b = 13.4479(16) Å, c = 13.6679(17) Å, V = 1786.3(4) Å3, Z = 4, R gt(F) = 0.0393, wR ref(F 2) = 0.0937, T = 173 K.

This paper presented a new method to evaluate Remote Sensing image quality, by comparing ZY1-02C, ZY3, and SPOT5 images on the engineering quality and spectral quality. It is important to explore new options to evaluate different Remote Sensing image sources quality, in order to ensure the users could apply a best fit data source to environmental monitoring, ecological monitoring and so on. In this article, there were three aspects in the engineering quality assessment part, including the statistical character, the texture and the energy. And in the spectral quality assessment part, the imaging space, the curve space and the characteristic space were built to compare and measure different spectral ability of extracting ground objects among ZY1-02C, ZY3 and SPOT5 images. The result shows such a Remote Sensing image quality assessment can be generalized to choose suitable data source for some specific field.

Current methods that use hyperspectral remote sensing imagery in the detection and extraction of marine oil spills are quite popular. Because the mixed pixels exist broadly in the hyperspectral images, the automatic and accurate end member extraction technology plays most essential role in the hyperspectral unmixing. This paper proposed a data field-spectral preprocessing module prior to end member extraction. We compared it with other existing preprocessing algorithms by different image size, different dataset, different end member number, different noises, and combined them with different end member extraction algorithms. It is proved that the proposed algorithm provides accurate end member detection, including anomaly end member, so it has greater accuracy, stronger noise resistance and saves more time. Especially the proposed method is effective in marine oil spill monitoring.

A series of LMOFs, consisting of three groups of isostructural compounds, [Ln(3-H-5-phenoxonicotinato)(ox)(H2O)2]n 1 (Ln = La(1a), Pr(1b), Nd(1c), 5-Hydroxynicotinic acid = C6H5NO3, ox = C2O42 −), {[Ln(3-H-5-hydroxynicotinato)(ox)1.5(H2O)]⋅H2O}n 2 (Ln = Sm(2a), Gd(2b), Tb(2c), and {[Ln(3-H-5-phenoxonicotinato)(ox)(H2O)]⋅H2O}n 3 (Ln = Dy(3a), Er(3b), have been hydrothermally synthesized and structurally determined by X-ray diffraction analyses. Compounds in group 1 are constructed by mixed μ3-3-H-5-phenoxonicotinato and oxalate bridging ligands and Ln3 + ions, exhibiting a 3D covalent network with empty 1D microchannels, featuring a 3,5-connected topology symbol of {42⋅ 65⋅ 83}⋅{42⋅ 6}. Compounds in group 2 present a brick-well-liked 2D network generated by both metal ions and oxalate groups at a side-by-side way. Compounds in group 3 are isotopological to those in group 1, accompanying 1D microchannels being occupied by coordinated water molecules. Antiferromagnetic interactions between praseodymium metal centers are observed from the magnetic susceptibility of compound 1b. In addition, luminescence measurements indicate that the terbium complex 2c is a strong green luminescence emitter.

Three new coordination polymers, namely [Mn2(5-phenoxonicotinato)2] ( 1 ), [Cd2(5-phenoxonicotinato)2] ( 2 ), and [Fe2(5-phenoxonicotinato)2] ( 3 ), have been synthesized under hydrothermal conditions and characterized structurally by single-crystal X-ray diffraction. The structure of compound 1 can be described as a 3D metal-organic framework which is constructed by two kinds of crystallographical unique Mn cations and one kind of μ6-5-phenoxonicotinato bridging ligand, featuring a 6,6-connected {3·410·64}{49·66} topology structure. Taking Cd and Fe ions in place of Mn ions respectively, two new compounds 2 and 3 are successfully obtained which are isostructural with 1. In addition, the magnetic property of compound 1 is investigated in detail.

One-dimensional manganese(II) complex, [Mn2(5-nbdc)2(imH)6] · 2H2O (1) (5-nbdcH2 = 5-nitro-1,3-benzenedicarboxylic acid and imH = imidazole), has been hydrothermally synthesized and structurally characterized by X-ray crystallography with the following data: orthorhombic, space group Pna2(1), M r = 972.63 for Mn2C34H34N14O14, a = 13.3391(12) A, b = 16.4657(15) A, c = 18.2177(16) A; V = 4001.3(6) A3, Z = 4, D calcd 1.615 g cm−3, µ = 0.718 mm−1, the final R = 0.0490 and wR = 0.1277 for 7278 observed reflections (I > 2σ(I)). Complex 1 exhibits very weak intra-chain ferromagnetic coupling (J k−1 = 0.001 K) with g = 1.930. The magnetism of a one-dimensional cobalt(II) complex [Co(5-nbdc)2(imH)2] n (2) indicates weak intra-chain anti-ferromagnetic coupling (J k−1 = −0.067 K) with g = 2.0791.

Two one-dimensional cobalt (II) and copper (II) complexes, [Co(5-nbdc)2(imH)2]n (1) and [Cu3(5-nbdc)2(OH)2(imH)2]n (2) (5-nbdcH2 = 5-nitro-1,3-benzenedicarboxylic acid and imH = imidazole) have been synthesized and structurally characterised. Complex 2, a molecular ladder consisting of the linear trinuclear copper (II) subunits and featuring the mixed μ-hydroxo and μ-carboxylato bridges, indicated a strong intra-trimer antiferromagnetic coupling (J/k = −43.8 K) and a weak inter-trimer antiferromagnetic coupling (J′/k = −2.5 K) with the corresponding g value 2.011.

Four polymeric complexes [M(SCN)2(4-abaH)2]n [M=Co(II) (1) or Cd(II) (2), 4-abaH=4-aminobenzoic acid], [Zn(N3)(4-aba)]n (3) and [Cd(N3)(4-aba)(H2O)]n (4) were prepared from the reactions of 4-abaH with M(SCN)2 [M=Co(II) or Cd(II)] and M(N3)2 [M=Zn(II) or Cd(II)] at different pH values. Their crystal structures have been determined by single-crystal X-ray diffraction. Both 1 and 2 consist of one-dimensional chains [M(μ-1,3-SCN)2(4-abaH)2]n, in which each pair of the lateral carboxylic groups form double hydrogen bonds to furnish infinite two-dimensional sheets. In 3, the Zn(II) atoms are bridged by μ-1,1-azide groups and μ2-carboxylate-O,O′ groups into an infinite zigzag chain featuring six-membered (ZnNZnOCO)n rings, which are further connected by the 4-aba-N,O,O′ groups to generate a two-dimensional network. In 4, however, adjacent Cd(II) atoms are bridged by μ-1,1,3-azide groups to form an infinite chain with both four-membered Cd2(μ-1,1-N3)2 and eight-membered Cd2(μ-1,3-N3)2 rings. These chains are further connected by the 4-aba-N,O groups to generate a three-dimensional brickwall-like network. The results show significant effect of pH on the formation of the network structures.

Four infinite complexes X 1 [Ni(NCS) 2 (4,4'-oda) 2 ], X 2 [Co(NCS) 2 (4,4'-oda) 2 ] and X 2 [M(N 3 )(4,4'-oda) 2 ]NO 3 [M=Cd II ( 3 ) or Co II ( 4 )] were obtained by reactions 4,4'-oxydianiline (4,4'-oda) with Ni(SCN) 2 , Co(SCN) 2 , Cd(N 3 ) 2 and Co(N 3 ) 2 , respectively which have been structurally established by single-crystal X-ray diffraction. Complex 1 contains one-dimensional double-stranded chains comprising 24-membered Ni 2 (4,4'-oda) 2 macrocycles, each formed by two 4,4'-oda ligands and two octahedral Ni II centers. Complex 2 exhibits two-dimensional non-interpenetrating networks consisting of large 48-membered macrocycles each formed by four 4,4'-oda ligands and four octahedral Co II centers. The crystal structures of 3 and 4 are isomorphous and both contain one-dimensional double-stranded chains comprising 24-membered M 2 (4,4'-oda) 2 macrocycles, which are interlinked by w -1,3-azide groups to generate cationic two-dimensional sheets. These sheets are further connected by hydrogen bonds ...

Two isomorphous molecular ladders formulated as [M2(4,4‘-bpy)3(phba)2(H2O)2](NO3)2·4H2O (4,4‘-bpy = 4,4‘-bipyridine; phba = 4-hydroxybenzoate; M = Cu2+ or Co2+), shown by X-ray, feature a novel ladder motif having different inner rungs (4,4‘-bpy) and lateral arms (phba). Penetration of the lateral arms into the squares of adjacent ladders results in a novel 3-D network.

Three compounds [4,4′-bipyH2][M(NCS)4] (M = Mn2+, Co2+ or Zn2+; 4,4′-bipy = 4,4′-bipyridine) were obtained from the reactions of 4,4′-bipy with M(SCN)2 in acidic solution and their crystal structures determined by single-crystal X-ray diffraction. All crystallise isomorphously in the chiral orthorhombic space group P21212. The tetrahedral [M(NCS)4]2− anions are inter-connected by S⋯S contacts (ca. 3.63 A) and are hydrogen bonded with the diprotonated [4,4′-bipyH2]2+ cations [N⋯S 3.241 A in 1; 3.235 A in 2; 3.239 A in 3] to form two-dimensional, highly wavy networks with hourglass-shaped cavities (ca. 12.3 A long; 9.4 A wide at the ends, 6.8 A at the waist). These two-dimensional networks are stacked with each other to furnish a channel accommodating the diprotonated [4,4′-bipyH2]2+ cations. The three organic–inorganic hybrid compounds are thermally stable with melting points above 230 °C. The powder second harmonic generation efficiencies were measured as moderate.

The title complex, [Zn(N3)(C6H4NO2)]n, formed from Zn cations, nicotinate and azide groups, exhibits a three-dimensional non-centrosymmetric covalent network. The coordin­ation sphere of the central metal ions is completed by an N3O2 five-coordinate coordination model showing distorted trigonal–bipyramidal geometry. Adjacent Zn atoms are bonded by μ2-carboxyl­ate groups and a μ2-azide bridge into one-dimensional helical double-stranded chains with the six-membered ring running along the a axis, and these chains are further linked by μ3-nicotinate groups via covalent bonds, extending into two-dimensional sheets and further generating a non-centrosymmetric three-dimensional covalent network.

Closed-form expressions of three-dimensional effective moduli of symmetric laminates, which are based on the assumption of constant in-plane strains and constant interlaminar stresses through the thickness, had been proposed by Chou and Carleone (1972) and later re-proposed by Sun and Li (1988). This article modified the effective interlaminar shear moduli to account for the effect of stacking sequence by assuming the parabolic distribution of interlaminar shear stresses through the thickness. In this article, the effective three-dimensional moduli are also re-presented in such forms that it could be seen that several particular forms of the rule of mixture apply for individual stiffness or compliance components. As a result, four stiffness invariants and one compliance invariant are developed. The invariance is helpful in checking the reliability of measurements. The effective moduli predicted by this article are found to be in good agreement with the experimental data measured by ultrasonic methods.

An integrated equivalent stiffness model is developed to describe a grid structure with or without laminate skins. The in-plane bending and shear of ribs are included without introducing any extra degree of freedom so that Mindlin's plate theory can still be adopted. As a result, the model can be directly incorporated with the existing FEM technique and take advantage of commercial codes. The proposed model is demonstrated to be efficient and reasonably accurate. If high precision is required, the equivalent stiffness model can be incorporated with the exact FEM modeling to obtain a refined stress analysis. Hygrothermal behavior and local buckling are also taken into account. Using the model as a tool, the performance of composite grid structures can be compared to traditional laminates, sandwich plates and metal grid structures. A method of optimum design is established to design a grid structure with or without laminated skins. Multiple loads and multiple failure mechanisms are considered. Discrete design is also included. Furthermore, the method can be easily incorporated with FEM to perform structural optimization. The optimization code is demonstrated to be a very powerful design tool. Finally, a user-friendly computer code is developed to perform the above tasks.

In the title compound, {[Ho(2)(C(6)H(4)NO(3))(2)(C(2)O(4))(2)(H(2)O)(2)]·2H(2)O}(n), the Ho(III) atom is coordinated by three O atoms from three 5-hy-droxy-nicotinate ligands, four O atoms from two oxalate ligands, each lying on an inversion center, and one water mol-ecule in a distorted square-anti-prismatic geometry. The 5-hy-droxy-nicotinate ligand is protonated at the N atom and deprotonated at the hy-droxy group. The Ho(III) atoms are bridged by the carboxyl-ate and phenolate O atoms, forming a three-dimensional framework. N-H⋯O and O-H⋯O hydrogen bonds, as well as π-π inter-actions between the pyridine rings [centroid-centroid distance = 3.794 (2) Å], are observed.

The two-dimensional hydrogen-bonded honeycomb networks formulated as (4,4′-H2bipy)2[Ni(NCS)4(H2O)2](NO3)2(4,4′-H2bipy=4,4′-bipyridinium) with R1012(64) rings and ca. 24×20 A internal dimensions are triply interwoven to generate two-dimensional `chicken-coop' sheets, featuring unusual hydrogen bonds involving the NO3− groups.

Nanoporous thin films fabricated by both a core-shell-shaped organic-inorganic hybrid sphere (octa(2,4-dinitrophenyl)silsesquioxane, ODNPSQ) and a four-leg-numbered surfactant (polyoxyethylene sorbitan monolaurate, Tween-20) for porogens in a higher molecular weight precursor (polyphenylsilsesquioxane, PPSQ) were characterized, respectively, by grazing incidence small-angle X-ray scattering (GISAXS), and the measured 2D GISAXS profiles were analyzed quantitatively by using a GISAXS formula based on the distorted wave Born approximation (DWBA). The fitted 2D GISAXS data show that the PPSQ porous thin films imprinted with ODNPSQ porogen exhibit sphere-shaped closed pores with the average pore size within a range of 1.18-3.12 nm and pore size distribution widths about 3.0 nm when the porogen loadings increase from 10 to 40 wt % and those imprinted with Tween-20 porogen give out an average pore size of 1.07-1.29 nm and pore size distribution widths about 2.0 nm with the porogen loading varying from 5 to 30 wt %. The nanoporous dielectric thin films imprinted with ODNPSQ porogen show a reducing to the molecular aggregation of porogens and significant antiphase separation behavior in the cross-linked matrix.

The title coordination polymer, [Zn(C6H4NO3)2]n, was prepared under hydrothermal conditions by the reaction of zinc nitrate with 5-hydroxynicotinic acid in the presence of malonic acid. In the structure, the ZnIIion is coordinated by two carboxylate O atoms and two pyridine N atoms of four 5-hydroxynicotinate ligands in a distorted tetrahedral coordination environment. The μ2-bridging mode of each anion leads to the formation of a three-dimensional framework structure. Intermolecular hydrogen bonds between the hydroxy groups of one anion and the non-coordinating carboxylate O atoms of neighbouring anions consolidate the crystal packing.

In the title compound, [Eu2(C6H5NO3)2(C2O4)3(H2O)4] n , the Eu(III) atom is bonded to one O atom from a monodentate 5-hy-droxy-pyridin-1-ium-3-carboxyl-ate ligand, six O atoms from three oxalate ligands and two water mol-ecules, exhibiting a highly distorted tricapped trigonal geometry. Three independent oxalate ligands, each lying on an inversion center, bridge the Eu(III) atoms, forming a brickwall-like layer parallel to (001), which is stabilized by intra-layer O-H⋯O hydrogen bonds. The layers are further linked through inter-layer O-H⋯O and N-H⋯O hydrogen bonds and π-π inter-actions between the pyridine rings [centroid-centroid distance = 3.5741 (14) Å] into a three-dimensional supra-molecular network.

The title compound, [Ni(C7H5O2)2], exhibits a mononuclear structure in which the central NiII atom is located on an inversion centre and is coordinated by four O atoms from two salicylaldehyde ligands in a distorted square-planar geometry. The complex was obtained by the reaction of salicylaldehyde and nickel(II) nitrate hexahydrate in ethanol, using 3-amino-1,2-propanediol as a growth-directing reagent.

The title polymeric complex, poly[tetraaquatricadmium(II)-hexa-mu-nicotinato], [Cd(3)(C(6)H(4)NO(2))(6)(H(2)O)(4)](n), exhibits two types of metal centers, i.e. a seven-coordinated Cd atom and a six-coordinated Cd atom located on an inversion center. The seven-coordinated Cd atoms are linked by kappa(3)N:O,O'-nicotinate bridges into one-dimensional chains that are further linked by kappa(2)N,O-nicotinate-Cd2-kappa(2)N,O-nicotinate bridges into a two-dimensional network which is parallel to the xy plane and which contains large 24- and 36-membered rings.

In the title compound, [Nd(2)(C(6)H(3)BrNO(2))(6)(H(2)O)(4)]·2H(2)O, the Nd(III) ion is coordinated by nine O atoms from one chelating 5-bromo-nicotinate ligand, four bridging 5-bromo-nicotinate ligands and two water mol-ecules, exhibiting a distorted three-capped triangular-prismatic geometry. Two Nd(III) ions are bridged by four carboxyl-ate groups in bi- and tridentate modes, forming a centrosymmetric dinuclear unit, with an Nd⋯Nd distance of 4.0021 (5) Å, and intra-molecular π-π inter-actions between the pyridine rings [centroid-centroid distance = 3.960 (2) Å]. Inter-molecular π-π inter-actions [centroid-centroid distances = 3.820 (2) and 3.804 (2) Å] and O-H⋯N and O-H⋯O hydrogen bonds connect the dinuclear mol-ecules into a three-dimensional supra-molecular network.

The crystal structure of the coordination polymer [Mn3(N3)2(nta)4(H2O)2]n (nta = nicotinate) consists of trinuclear subunits bridged by mixed μ-1,1-azide and μ-carboxylate-O,O groups, which are linked by μ3-nta-N,O,O ligands into a three-dimensional network exhibiting ferrimagnetic-like ordering.

The title compound, C(25)H(28)O(7), was prepared by the base-catalysed reaction of 3,4,5-trimethoxy-benzaldehyde with cyclo-penta-none. The mol-ecule has crystallographic twofold rotation symmetry and adopts an E-configuration about the central olefinic bonds. The two benzene rings and the central cyclo-penta-none ring are almost coplanar [dihedral angle = 4.7 (2)°].

In the title compound, C21H26N2O3, the mol­ecule adopts an E configuration about the central C=N double bond and exists in the phenol–imine tautomeric form. The two benzene rings make a dihedral angle of 38.5 (4)°. Intra­molecular O—H⋯N hydrogen bonding is present.