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Two novel 3d–4f coordination polymers [Ln(NiL)(Nipt)(C2O4)0.5 · H2O] · H2O (Ln = Er (I), Eu (II) (H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclopentadeca-7,13-dien; H2Nip = 5-nit-roisophthalic acid) were obtained by using 5-nitroisophthalate and mononuclear macrocyclic oxamide complex NiL as co-ligand to react with Ln(NO3)3 ⋅ 6H2O (Ln = Er, Eu) under solvothermal condition, and characterized by single crystal X-ray diffraction (CIF files CCDC nos. 1587618 (I) and 1587619 (II)). Two complexes are isostructural structure and exhibit a two-dimensional network architecture formed by [Ln(III)Ni(II)] units via the oxamide, 5-nitroisophthalate and oxalate bridges, and adjacent 2D structures are linked together with C–H⋅⋅⋅O and O–H⋅⋅⋅O intermolecular hydrogen bonds to form a 3D superamolecular architectures. The fluorescence properties of I and II are also characterized.

Three novel 3d–4f heterometal complexes [Ln(NiL)3(Btca)(NO3)] · xH2O (Ln = Sm(III) (I), Pr(III) (II), Eu(III) (III) (H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien, H2Btca = benzotriazole-5-carboxylic acid) were solvothermally synthesized and characterized by singlecrystal X-ray diffraction (CIF files CCDC nos. 1555557 (I), 1555555 (II), 1555556 (III)). They crystallized in the monoclinic space group P21/n for I (x = 1.5) and C2/c for (II) and (III) (x = 1), respectively. In these complexes, the central Ln(III) and external nickel ions are bridged by macrocyclic oxamide groups. The metal center of Ln(III) resides in a distorted bicapped square antiprism surrounding with six oxygen atoms of three oxamide groups, two oxygen atoms of Btca2– ion and two oxygen atoms of NO3-. Furthermore, there are C–H···O and/or C–H···N hydrogen bond interactions among nitrate, benzotriazole-5-carboxylate, macrocyclic oxamide and water to form three-dimensional superamolecular architecture. The fluorescence properties of the compounds I and II are also discussed.

A novel heterometallic coordination polymer {[Cd2(NiL)2(Btca)4] · H2O} n (I) (H2L = 2,3-dioxo5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien, H2Btca = benzotriazole-5-carboxylic acid) was synthesized and structurally characterized by elemental analysis, IR spectroscopy, and single crystal X-ray diffraction (CIF file CCDC no. 1043065). Complex I exhibits a two-dimensional network structure formed by Cd2Ni2 units via the oxamide and benzotriazole-5-carboxylate bridges. It crystallizes in the monoclinic system, space group P21/c. The lattice parameters are: a = 1.24488(8), b = 2.75370(19), c = 1.49336(10) A, β = 103.1070(10)° and V = 4.9859(6) A3, Z = 4. The fluorescence properties of compound I are also discussed.

Three complexes with the formula [Co(Ip)(CuL)(H2O)2] · H2O (I), [Co(Ip)(NiL)(H2O)2] · H2O (II), [Co(CuL)2(Hbtc)(H2O)] (III), (H2Ip = m-isophthalic acid; H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien; H3Btc = 1,3,5-benzenetricarboxylic acid) were synthesized and structurally characterized by elemental analysis, IR and UV spectroscopy. Single-crystal X-ray analyses reveal that the complexes I and II contain neutral heterometallic binuclear CoM (for I and II, M = Cu, Ni, respectively) moieties, and complex III contains discrete neutral trinuclear CoCu2 moieties. The structures of I–III consist of two-dimensional supramolecular architecture formed by strong O-H…O intermolecular hydrogen bonds. Furthermore, the magnetic properties of complex I were investigated and discussed in detail.

One novel heterometallic trinuclear complex of macrocyclic oxamide [Ni(CuL)2(HBTC)H2O] (I) (H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclopentadeca-7,13-dien; H3BTC = 1,3,5-benzenetricarboxylic acid) has been solvothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy, XRD, and single-crystal X-ray diffraction. The crystals crystallize in the monoclinic system, space group P21/c, a = 11.435(3), b = 20.646(5), c = 18.430(5) A, β = 94.131(4)°. The structure of I has oxamido-bridged trinuclear [Cu2IINiII] units and consists of two-dimensional supramolecular architecture formed by strong intermolecular hydrogen bonds. Furthermore, the magnetic properties of complex I was investigated and discussed in detail.

Multi-walled carbon nanotubes and one-dimensional (1D) carbon nanowires have been successfully fabricated through a solid-phase assembly of metal-containing C60 at 700 °C. From the microscopic observations on the morphologies and microstructures of the nanotubes and the nanowires, it is shown that the solid-phase assembly obeys a stepwise evolution process: C60 first assemble into carbon nanoparticles, and nanoparticles are organized into 1D nanowires, which finally transform into nanotubes via particle coalescence and structural crystallization and extension. In this process, the 1D wire-like nanoassemblies can be viewed as the intermediates of carbon nanotube formation, which record rich and convincible traces about nanotube evolution.

Single-crystal cuprous iodide semiconductor nanospheres were fabricated via a mild low-temperature solution route by using polyvinyl pyrrolidone as capping agent and the mixture of water and polyethylene glycol 400 as solvent. The structure, morphology, and properties of the products were characterized by powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, thermal gravimetry and photoluminescence spectrometry. The results showed that the products were CuI nanospheres of ca. 280–650 nm in diameter and were composed of quasi-trigonal particles of ca. 20–40 nm. The phase transformation temperature and the melting point of the products decreased by ca. 12 and 8 °C compared with the bulk CuI. The possible formation mechanism was discussed on the basis of experimental results.

Macrocyclic and supermolecular complexes [Cu2(NiL)2Cl4] (I) and [Cd2(CuL)2Cl4] (II) (H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-diene) have been synthesized and structurally determined by X-ray diffraction and IR spectrum. Complex I crystallizes in the monoclinic system with P21/n group, a = 10.9019(15), b = 14.3589(19), c = 12.4748(17) 0A, β = 108.645(2)°, Z = 4. Complex II crystallizes in the monoclinic system with P21/n group, a = 10.9784(16), b = 14.580(2), c = 12.8904(18) A, β = 109.339(2)°, Z = 4.

Planar nonpolar (1120) a-plane GaN films have been grown by metalorganic chemical-vapor deposition directly on cone-shaped patterned r-plane sapphire substrates (PRSS) fabricated by dry etching. High-resolution X-ray diffractometers 2θ-ω scan confirmed that the films grown on PRSS are solely a-plane oriented, and the full width at half maximum values (FWHM) of the X-ray rocking curves for (1120) GaN along [0001]GaN and [1100]GaN were found to be 684 and 828″, respectively. As compared to the film grown on conventional r-plane sapphire substrate which typically has (1120) omega FWHM values of 900 and 2124″ along [0001]GaN and [1100]GaN respectively, the film grown on PRSS exhibits overall reduced omega FWHM values, and much smaller anisotropy behavior of crystallinity with respect to the in-plane orientation. The surface morphology is also improved by utilizing the PRSS technique. Cross-sectional transmission electron microscopy analysis shows that the density of threading dislocations has been greatly reduced from ~ 1.0 × 1010 cm− 2 above the flat sapphire regions to ~ 1.0 × 107 cm− 2 above the protruding cone patterns. The improvement of crystal quality and the increase of light extraction efficiency by using cone-shaped PRSS technique lead to a strong enhancement in the light emission of a-plane GaN films. These results indicate that growth of a-plane GaN films on cone-shaped PRSS shows promise for use in high-quality and high-cost-performance nonpolar GaN based devices.

The complex incorporating macrocyclic oxamide of the formula [(CuL)2Cd(NCS)2] (H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-diene) has been synthesized and structurally characterized. The crystals crystallize in the monoclinic system, space group C2/c, a = 13.865(3), b = 14.390(3), c = 38.252(8) A, β = 92.45(3)°, Z = 8. The crystal structure unit is a trianuclear complex in which the Cd2+ and Cu2+ ions are bridged by the macrocyclic oxamide groups. The [(CuL)2Cd(NCS)2] units are alternately bridged by C-H···O to C-H···S hydrogen bond to form a 2D framework. The luminescent property of the compound is also discussed.

In this work, we have comparatively investigated the effects of the GaN, AlGaN, and AlN low-temperature buffer layers (BL) on the crystal quality of a-plane GaN thin films grown on r-plane sapphire substrates. Scanning electron microscopy images of the a-plane GaN epilayers show that using an AlGaN BL can significantly reduce the density of surface pits. The full-width at half-maximum values of the $$ (11\overline{2} 0) $$ x-ray rocking curve (XRC) are 0.19°, 0.36°, and 0.48° for the films grown using Al0.15Ga0.85N, GaN, and AlN BLs, respectively, indicating that an AlGaN BL can effectively reduce the mosaicity of the films. Room-temperature photoluminescence shows that the AlGaN BL results in lower impurity incorporation in the subsequent a-plane GaN films, as compared with the case of GaN and AlN BLs. The higher crystal quality of a-plane GaN films produced by the Al0.15Ga0.85N BL could be due to improvement of BL quality by reducing the lattice mismatch between the BL and r-sapphire substrates, while still keeping the lattice mismatch between the BL and epitaxial a-plane GaN films relatively small.

C9H18O3S6, orthorhombic, Pbca (no. 61), a = 17.419(2) Å, b = 10.6391(9) Å, c = 17.445(2) Å, V = 3232.9 Å3, Z = 8, Rgt(F) = 0.079, wRref(F2) = 0.252, T = 293 K.

This investigation examined the hydrogeochemical characteristics of different sulfide-containing gangue samples from the Hancheng mining area in Shaanxi, China. The changes in the hydrogeochemical properties during the leaching experiments on gangue samples containing different levels of sulfur (LSG-Low sulfur gangue, MSG-Moderate sulfur gangue and HSG-High sulfur gangue) were investigated by analyzing the major physical and chemical constituents (pH, EC, TDS, Ca2+, Mg2+, Na+, K+, Cl-, SO4 2-, HCO3 -, F-, and Fe). The results indicated that the release of SO4 2- and H+ from the dissolution of sulfide minerals resulted in low Ca2+ and HCO3 - concentrations at pH levels below 4.7 for the HSG leachate. Also for the HSG samples, the molar ratio of SO4 2-/Fe exceeded twice that which was expected, meaning the higher SO4 2- concentrations in the HSG samples result from more than just the oxidation of pyrite. Additionally, the leachate of three sulfide-containing gangue samples exhibited changes in the hydrogeochemical facies with the majority of changes occurring in the cation-type and anion-type facies. The HSG samples were of a [O-SO4] type for sulfide dissolution, the unaffected LSG samples were of a [Ca-HCO3] type, and the MSG samples were of a [Ca-HCO3-SO4] type.

C9H18S6, triclinic, P1̅ (no. 2), a = 5.637(1) Å, b = 14.748(4) Å, c = 17.913(4) Å, α= 86.663(5)°, β = 82.988(4)°, γ = 83.742(4)°, V = 1467.7 Å3, Z = 4, Rgt(F) = 0.072, wRref(F2) = 0.166, T = 293 K.

The dislocation structure in γ' in deformed single crystals of nickel-based superalloy SRR99 has been observed by weak-beam electron microscopy. Super-dislocations in γ', dissociated into Shockley partials, are continuous across the γ/γ' interface becoming a pair of unit dissociated dislocations in γ'. In γ' most dislocations are screws and their configurations are those of Kear-Wilsdorf locks; the complex stacking faults between the Shockleys lie on {111} and the antiphase boundaries between the superpartials lie on the cube cross-slip plane (010). Despite this sessile configuration of screw dislocation dissociation, the screw dislocations move on the primary slip plane (111) by the propagation of kinks whose four partials lie entirely on (111). Models of the anomalous increase of yield stress at high temperatures that assume a planar dissociation of screws on (111) require reconsideration in the light of these observations.