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A bulk Poly(vinyl alcohol)/ZIF-8 (PVA/ZIF-8) porous composite with aligned porous structure was prepared by ice-templating method. The microstructure of PVA/ZIF-8 porous composites was characterized by scanning electron microscopy (SEM). The results showed that the composites had regular pore structure and ZIF-8 nanoparticles were evenly distributed on the skeleton of PVA. X-ray diffraction (XRD) test results showed that the crystalline structure of ZIF-8 was well preserved in the composites. The specific surface area of the composite was characterized by nitrogen adsorption/desorption test. The specific surface area of the composite was up to 1160 m2·gt1. PVA/ZIF-8 porous composites could also support a certain weight with almost no volume shrinkage. The carbon dioxide adsorption quantity of the composite was up to 11.3 cm3·gt1, proving that PVA/ZIF-8 porous composite has a good application prospect in the field of carbon dioxide adsorption. [ABSTRACT FROM AUTHOR]

The stability, geometric structure and electronic properties of a novel body-centered tetragonal carbon allotrope Bct C 8 are systematically investigated. Bct C 8 are formed by sp 3 -bonded carbon atoms and can be regarded as a compressed bundle of carbon nanotubes (CNT). The transition path from CNT to Bct C 8 has been simulated, indicating a possible approach to synthesize Bct C 8 . The X-Ray diffraction, phonon and Raman spectroscopies are presented as reference for experimental studies. Besides, Bct C 8 is a semiconductor with an indirect gap of 1.66 eV and will transform to semimetal when doping with boron and nitride atoms. Furthermore, considering its porous structural character, the lithium storage capability of Bct C 8 are also discussed, a directional fast lithium-ion mobility with a rather low 0.04 eV barrier is revealed. Therefore, the Bct C 8 , once synthesized experimentally, would have fruitful applications in carbon-based electronics and energy storage. [ABSTRACT FROM AUTHOR]

The joining of arc sprayed Al-Zn coating and AZ91D substrate was achieved by solid-liquid compound casting. The microstructure evolution and formation mechanism of the interface were investigated in this study. A scanning electron microscopy (SEM), an energy dispersive spectroscopy (EDS), and an X-ray diffraction (XRD) were used to analyze the microstructure of the Al-Zn/AZ91D interface, whose results showed that the interface could be divided into three different intermetallic compound layers, which confirmed that the bonding between arc sprayed Al-Zn coating and AZ91D substrate was metallurgical. Among the three layers, the layer adjacent to the AZ91D substrate was mainly composed of δ-Mg, Mg 17 (Al, Zn) 12 and a small amount of lamellar Φ-Mg 21 (Al, Zn) 17 intermetallic compounds. The layer which was close to the Al-Zn pseudo-alloy coating mainly consisted of δ-Al, Al 2 Mg 3 Zn 3 and a small amount of oxides. The intermediate layer was mainly comprised of τ-Mg 32 (Al, Zn) 49 intermetallic compound. Furthermore, the microhardness values of interface zone were much higher than that of AZ91D substrate. [ABSTRACT FROM AUTHOR]

A facile and template-free solvothermal method was developed for the synthesis of microspheric g-C3N4/Bi2MoO6 photocatalysts. The obtained g-C3N4/Bi2MoO6 composites were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photo-electron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and ultraviolet-visible diffuse reflection spectroscopy (DRS). The XRD, FTIR, and HRTEM characterization results confirmed the formation of heterojunction structures at the interfaces of g-C3N4 and Bi2MoO6. The DRS results showed that the absorption edges of g-C3N4/Bi2MoO6 composites were red shifted in the visible light region with the increase of g-C3N4 content. The SEM and TEM images revealed that the composites exhibited a microsphere-like morphology and were composed of smaller nanoplates. The elemental mapping images revealed that g-C3N4 and Bi2MoO6 nanoflakes uniformly assembled together to form hierarchical flowers. Compared with pure g-C3N4 and Bi2MoO6, the as-prepared samples exhibited superior photocatalytic activity towards the degradation of dyes (Rhodamine B and Methyl blue) under visible light irradiation. The enhanced photocatalytic activity of g-C3N4/Bi2MoO6 composites could be attributed to their strong visible light absorption, the high migration efficiency of photo-induced carriers, and the interfacial electronic interaction. The electrochemical impedance spectroscopy (EIS) confirmed that the interface charge separation efficiency was greatly improved by coupling g-C3N4 with Bi2MoO6. It was also confirmed that the photo-degradation of dye molecules is mainly attributed to the oxidizing ability of the generated holes (h+) and partly to the oxidizing ability of ·O2− and ·OH radicals. [ABSTRACT FROM AUTHOR]

Highlights: [•] Newly synthesized 5-(aryliminomethyl)quinaldine-8-ol derivatives. [•] Trinuclear complexes of zinc 5-(aryliminomethyl)quinaldin-8-olates. [•] X-ray diffraction study on zinc complex. [•] The luminescent properties enhanced through coordination. [Copyright &y& Elsevier]

Abstract: A new inorganic–organic hybrid compound constructed from Keggin-type polyoxometalate and cadmium-organic units, namely, [Cd(Htrz)3]2[SiW12O40]·2H2O (1), [Htrz=1-H-1,2,4-triazole], has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, TG, and UV–vis absorption spectra. In compound 1, each [SiW12O40]4− cluster is modified by six [Cd(Htrz)3]2+ metal–organic fragments, meanwhile, each [Cd(Htrz)3]2+ also connects with three [SiW12O40]4− to built up a binodal (3,6)-connected 2D planar network with the (43)2(46·66·83)-kgd topology. Interestingly, [SiW12O40]4− cluster exhibits a rare coordination mode acting as a hexadentate ligand, in which all of the six terminal oxygen atoms in the equatorial plane are synchronously participated in coordination. The diffuse reflectivity spectrum shows it can be regarded as a wide gap semiconductor. Moreover, the photocatalytic performance shows good photocatalytic activity for the degradation of Rhodamine B. [Copyright &y& Elsevier]

Abstract: A new one-dimensional Co(II) coordination polymer, Co(L)(N3)2 (L = pyridinio-N-acetate), has been synthesized by a diffusion method and characterized by single crystal X-ray diffraction. In the compound, Co(II) ions are linked by mixed triple bridges (two end-on azides and a syn–syn carboxylate), which transmit ferromagnetic coupling with J=13.96cm−1. The compound exhibits field-induced metamagnetic behaviors below TN =2.3K with Hc=100Oe, due to weak antiferromagnetic interactions between chains. [Copyright &y& Elsevier]

Abstract: Continuous silicon carbide (SiC) fiber with a diameter of about 100μm was fabricated by two-stage chemical vapor deposition on tungsten filament. Microstructure of the fiber was investigated by means of scanning electron microscopy, X-ray diffraction, transmission electron microscopy and Raman spectrometry. The results showed that the fiber consists of tungsten core, a W/SiC interfacial reaction zone with the reaction products of W5Si3 and WC, and a predominant β-SiC layer. The W/SiC interface can be described as W/W5Si3/WC/SiC. The SiC originates at the surface of the WC with a buffer layer, in which β-SiC crystallites nucleate and grow with their preferred (111) orientation, exhibiting strong 〈111〉 fiber texture. Raman spectra revealed that the SiC in the fiber is stoichiometric, which is composed of β-SiC and amorphous SiC. Furthermore, the formation mechanism of W/SiC interfacial reaction zone and structural evolution of SiC are discussed. [ABSTRACT FROM AUTHOR]

A polyoxoniobate, [Cu(en)2]4{[Nb6O19H2]K(H2O)5}2 ⋅ (H2en) ⋅ 17H2O (en = ethylenediamine) (1), has been synthesized and characterized by elemental analysis, IR, XPS, TGA, and single-crystal X-ray diffraction. Compound 1 crystallizes in the triclinic system, space group P1, with a = 12.3533(16) Å, b = 12.7188(16) Å, c = 29.626(4) Å, α = 93.235(2)°, β = 96.094(1)°, γ = 106.098(2)°, V = 4429.0(10) Å3, Z = 2. The polyoxoanion is composed of a Lindqvist-type [Nb6O19H2]6- dimer bi-bridged via two K+. K+ is 10-coordinate with 10 oxygens, three from one [Nb6O19H2]6-, one from a terminal oxygen of another [Nb6O19H2]6- moiety, and the other six from water molecule. Adjacent dimeric polyoxoanions are linked to form an infinite 1-D chain via O-H ··· O hydrogen-bonding interactions which exist between the two water trimers and the dimeric polyoxoanions. [ABSTRACT FROM AUTHOR]

Perovskite-type LaFeO3 and α-Fe2O3 with high specific surface areas were directly prepared with appropriate stearic acid–nitrates ratios by a novel stearic acid solution combustion method. The obtained powders were characterized by XRD, FT-IR and XPS techniques. The catalytic activities of perovskite-type LaFeO3 and α-Fe2O3 for the thermal decomposition of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) were investigated by TG and TG–EGA techniques. The experimental results show that the catalytic activity of perovskite-type LaFeO3 was much higher than that of α-Fe2O3 because of higher concentration of surface-adsorbed oxygen (Oad) and hydroxyl of LaFeO3. The study points out a potential way to develop new and more active perovskite-type catalysts for the HMX thermal decomposition. [Copyright &y& Elsevier]

Abstract: In this paper, InN thin films were deposited on Si (100) and K9 glass by reactive direct current magnetron sputtering. The target was In metal with the purity of 99.999% and the gases were Ar (99.999%) and N2 (99.999%). The properties of InN thin films were studied. Scanning electron microscopy (SEM) shows that the film surface is very rough and energy dispersive X-ray spectroscopy (EDX) shows that the film contains In, N and very little O. X-ray diffraction (XRD) and Raman scattering reveal that the film mainly contains hexagonal InN. The four-probe measurement shows that InN film is conductive. The transmission measurement demonstrates that the transmission of InN deposited on K9 glass is as low as 0.5% from 400nm to 800nm. [Copyright &y& Elsevier]

By assembling CoII ions and a combination of 5-(4-pyridyl)tetrazole (4-ptz) and formate ions, two distinct metal-organic frameworks, [Co3(4-ptz)5(HCOO)(H2O)2] and [Co3(4-ptz)4(dmf)2(HCOO)2 ] (dmf= N, N′-dimethylformamide), were synthesized. They were both characterized by single-crystal X-ray diffraction, IR spectroscopy, thermogravimetric analysis, and powder X-ray diffraction. Structural analyses revealed that by slightly modulating the coordination environment of the trinuclear cobalt cluster, two complexes were formed featuring unusual six-connected nets reminiscent of a pyrazole-type linear trinuclear cobalt cluster as compared with the classic eight-connected bcu topology. In addition, [Co3(4-ptz)5(HCOO)(H2O)2] interacted strongly with CO2, with an adsorption enthalpy of 29.2 kJ mol−1, and in a selectivity study, the uptake ratios of CO2/N2 (from a 15:85 mixture) and CO2/CH4 (50:50 mixture) were 77.6 and 37.7, respectively. Magnetic studies on both complexes revealed weak antiferromagnetic coupling between the CoII ions. [ABSTRACT FROM AUTHOR]

Abstract: Heterogeneous ion solution is an important method to improve the wanted property of polycrystalline materials. In this paper, for the purpose of infrared radiation property modification, different contents Fe2O3 were doped in MgO–Al2O3–SiO2 system glasses. The effects of Fe2O3 doping on nucleation mechanism, crystallization behaviors and especially infrared radiation properties of this cordierite-crystalline based glass-ceramics were systematically investigated by means of differential thermal analysis (DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The results show that, the doping of iron ion can promote the phase separation of this magnesium aluminosilicate glass, and therefore change the crystallization mechanism of this glass from surface crystallization to bulk crystallization. The iron ion incorporates into the crystal structure of cordierite by mean of substituting Mg2+ in M site. The substitution of Fe3+ to Mg2+ can form the vacant site of Mg2+ cations. For the effects of lattice distortion, impurity and vacancy defects which caused by the incorporation of iron ion, the infrared radiation performance of cordierite based glass-ceramics can be improved effectively. [ABSTRACT FROM AUTHOR]

A series of seven mixed-ligand coordination polymers, namely {[Cd4(H2L1)4(suc)4]·3H2O}n(1), {[Cd4(H2L1)3(suc)4]·5H2O}n(2), {[Cd2(HL1)2(suc)]·8H2O}n(3), {[Cd(H2L2)(suc)]·3H2O}n(4), {[Cd(H2L3)(suc)]·3H2O}n(5), {[Co(H2L1)(chdc)(H2O)]·H2O}n(6), {[Co(H2L2)(chdc)(H2O)]}n(7) have been produced by the reaction of three 2-amino-4,6-dipyridylpyrimidine isomers (H2L1, H2L2, H2L3) and secondary ligand 1,4-succinic acid (H2suc) or 1,4-cyclohexanedicarboxylic acid (H2chdc) with Cd(II) and Co(II) salts under hydrothermal conditions. All these compounds have been structurally determined by elemental analysis, IR and single-crystal X-ray diffraction. The three isomers are introduced in a mixed-ligand system for the first time. For the H2L1–H2suc–Cd(II) system, it is found that the structures of compounds 1–3exhibiting a 1-D double-chain, a rare 1-D quadruple nano-chain and a 2-D network with (6,3) topology, respectively, are influenced by the ratio of metal-to-ligand. When H2L2 and H2L3 were used instead of H2L1, two 1-D chains (compounds 4and 5) were obtained. Although they have the same molecular formula and structure motif, their supramolecular networks constructed by hydrogen-bondings and π–π stacking interactions are different. When H2L1 and H2L2 were introduced into the Co(NO3)2–H2chdc system, compounds 6and 7were successfully isolated, and display a zigzag chain and a helical chain, respectively. Interestingly, the cis- and trans-conformations of H2chdc were separated completely in the two compounds. The results reveal that both the coordination structure and the supramolecular assembly could be directed by the ligand isomers. Furthermore, several intriguing water clusters have been observed in these mixed-ligand compounds, such as a novel (H2O)10cluster in 2, a 2-D water net formed by (H2O)8clusters in 3, a 1-D undulated water chain in 4and a chair-shaped (H2O)6cluster in 5. The solid-state properties of compounds 1–7such as thermal stability and fluorescence have also been investigated. [ABSTRACT FROM AUTHOR]

Abstract: A new fluoride borate crystal, CdZn2KB2O6F, has been synthesized by flux-supported solid-state reaction. The crystal structure has been determined by single-crystal X-ray diffraction. It crystallizes in the trigonal space group with a=5.0381(6)Å, b=5.0381(6)Å, c=15.1550(19)Å, α=90.00°, β=90.00°, γ=120.00°, Z=2. The crystal represents a new structure type in which ZnBO3 layers are connected through bridging fluorine and cadmium atoms alternately along the c-axis. K+ cations are filled in the intralayer open channels to balance charge. IR and Raman spectra further confirm the crystal structure. Photoluminescent measurement reveals that CdZn2KB2O6F exhibits blue fluorescence at room temperature in the solid-state. [Copyright &y& Elsevier]

Abstract: InN thin films were fabricated by reactive direct current magnetron sputtering. Different Ar and N2 flow rates were tried in order to tune the properties of the obtained films. Scanning electron microscopy (SEM) shows that growth of InN on Si (100) follows island growth mode. Energy dispersive X-ray spectroscopy (EDX) shows that the film contains In, N and O. When Ar flow rate is 75sccm and N2 changes from 25sccm to 150sccm, the atomic ratio of N increases while that of In and O decreases. X-ray diffraction (XRD) and Raman scattering reveal that the film contains hexagonal InN and cubic In2O3. The XRD peak intensity related to cubic In2O3 decreases with the increase of N2 flow rate. The four probe measurement shows that all the samples have very low sheet resistances. The transmission of InN deposited on K9 glass is very low. [Copyright &y& Elsevier]

Abstract: Three new complexes Ln(BDC)1.5(DEF) [Ln=La(1), Ce(2), Nd(3); H2BDC=1,4-benzenedicarboxylic acid; DEF= N,N-diethylformamide] have been solvothermally synthesized and characterized by single-crystal X-ray diffraction. Complexes 1–3 are isostructural and crystallize in triclinic space group . They display three-dimensional frameworks and 18.7986Å×11.3230Å rhombic channels along the a axis without interpenetration. Two eight-coordinated metal centers are connected with two dimonodentate BDC groups and two chelating/bridging bidentate BDC groups to give a paddle-wheel building block. The building blocks are connected through two carboxyl groups to lead to a one-dimensional infinite inorganic chain (–M–O–C–O–M–) along the [100] direction. Thermogravimetric analyses (TGA) and X-ray powder diffraction (XPRD) were determined for the three complexes. An observed intense blue luminescence with an emission band peaking at 372nm for them may result from ligand-to-metal charge transfer (LMCT). Variable-temperature magnetic susceptibility of 2 and 3 was investigated and found deviated from the Curie–Weiss law. [Copyright &y& Elsevier]

Abstract: The reactions of divalent metal salts and 4,6-dipyridyl-2-aminopyrimidine ligands gave rise to three metal–organic coordination compounds: [ZnL1(OOCCH3)2] (1), [Co(L2)2(OH)2]·3H2O (2), and [Cu2(L2)2(OH)2(H2O)2](NO3)2·0.5H2O (3) [L1=4,6-bis(2-pyridyl)-2-aminopyrimidine; L2=4-(2-pyridyl)-6-(4-pyridyl)-2-aminopyrimidine] and their crystal structures were determined via single-crystal X-ray diffraction. In the three structures, L1 and L2 both exhibit terminal coordination mode. As the ligands contain both hydrogen bonding donors and acceptors, hydrogen bonding interactions play a crucial role in construction of supramolecular structures. In compound 1, the mono-nuclear complexes were connected to dimer structure by hydrogen bondings; in compound 2, dimer units were constructed through intermolecular hydrogen bondings and the crystallographic water molecules link the dimers into a 1-D supramolecular chain; and in compound 3, a complicated 3-D supramolecular architecture was formed via a series of hydrogen bondings. Moreover, the compounds 1–3 display room-temperature luminescent properties. [Copyright &y& Elsevier]

A structurally stable carbon allotrope with plentiful topological properties is predicted by means of first-principles calculations. This novel carbon allotrope possesses the simple space group C2/m, and contains simultaneously sp , sp 2 and sp 3 hybridized bonds in one structure, which is thus coined as carboneyane. The calculations on geometrical, vibrational, and electronic properties reveal that carboneyane, with good ductility and a much lower density 1.43 g/cm3, is a topological metal with a pair of nodal lines traversing the whole Brillouin zone, such that they can only be annihilated in a pair when symmetry is preserved. The symmetry and topological protections of the nodal lines as well as the associated surface states are discussed. By comparing its x-ray diffraction pattern with experimental results, we find that three peaks of carboneyane meet with the detonation soot. On account of the fluffy structure, carboneyane is shown to have potential applications in areas of storage, adsorption and electrode materials. Image 1 [ABSTRACT FROM AUTHOR]

A novel hierarchical BiOI/Bi 2 MoO 6 composites are prepared by a facile precipitation–deposition method. The prepared photocatalyst was characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM), diffuse reflectance spectroscopy (DRS), and X-ray photoelectron spectrometer (XPS). The resulting BiOI/Bi 2 MoO 6 composites exhibit excellent photocatalytic activity and stability towards the degradation of methylene blue (MB) and bisphenol A (BPA) in aqueous solution under visible light irradiation. The optimal composite with 25% BiOI content shows the highest photocatalytic activity for MB degradation. The enhanced photocatalytic activity is mainly attributed to the formation of BiOI/Bi 2 MoO 6 heterojunction that can facilitate the separation and transfer of the photo-generated charge carriers. The roles of active species in the photocatalytic process are discussed by using different types of active species scavengers. Meanwhile, combined with the photoluminescence (PL) and electrochemical impedance spectroscopy (EIS), the degradation mechanism of the photocatalysts is proposed. It is hoped that the work could provide valuable information on the design of specific structure materials with more excellent properties and set the foundation for the further industrial application. [ABSTRACT FROM AUTHOR]

Silicon carbide-reinforced graphite composites were prepared by hot-pressing mixtures of flake graphite and Si powder with various mass ratios under vacuum. The microstructure and phase compositions were characterized by SEM and XRD. Results indicated that SiC, resulting from the reaction between graphite and silicon, was uniformly dispersed in the graphite matrix. The bend strength of the composites increased from 112 to 206 MPa with increasing silicon content from 28.06 to 37.94 mass%. The oxidation resistance of the composites increased with their silicon content. The coefficient of friction of the composites remained at a low constant value of about 0.1 when the Si content was below 31.46 mass%. [New Carbon Materials 2015, 30(1): 92–96] [ABSTRACT FROM AUTHOR]

The cerium(III)-containing polyoxotungstates (III)-(VII) are characterized by single crystal XRD, IR spectroscopy, XPS, ESI-MS, and electrochemical measurements. [ABSTRACT FROM AUTHOR]

The jet swell effect in the wet spinning of polyacrylonitrile (PAN) fiber was studied by optical microscopy and the jet swell ratio was obtained through directly measuring the diameter of the freely extruded fibers. For reflecting the actual drawing situation of the fibers in the coagulation process, the jet stretches were then corrected from the apparent values to the true values, and their effect on the cross-sectional morphology, internal structure, and orientation of the wet-spun PAN fibers was studied by optical microscopy, scanning electron microscopy, and X-ray diffraction, respectively. The results showed that jet stretch plays an important role in eliminating the adverse effects caused by the jet swell effect and affects the fiber structure; PAN fibers of uniform denier, dense and homogenous structure, and high orientation can only be obtained at a suitable jet stretch. [ABSTRACT FROM PUBLISHER]

Abstract: N-doped TiO2/rectorite (NTR) mesoporous materials were synthesized and characterized by XRD, TEM, BET, XPS, FTIR, and UV–vis DRS. The XRD analysis indicated that the layered structure of rectorite was destroyed to some extent. TiO2 in the composites exists in anatase phase. The XPS and FTIR analyses confirm that nitrogen was doped into TiO2 lattices successfully. The UV absorption edges of the NTR samples showed a red shift as compared to that of the undoped TiO2. The NTR photocatalyst prepared at 400°C showed a strong adsorption capability and a high visible light photocatalytic activity, which could be attributed to the synergetic effects of the rectorite structure and the N-doping. [ABSTRACT FROM AUTHOR]

Abstract: Five novel complexes, Co(OBt)2 ·7H2O (1) (OBt=1-hydroxybenzotriazole ion), Ni3(OBt)6 ·6H2O (2), [Ag(OBt)(HOBt)] n (3), [Zn(OBt)2] n (4) and [Cu2(OBt)4 ·3H2O] n (5) were synthesized by hydrothermal method and characterized by elemental analysis, IR spectroscopy, TGA, XRPD, and single-crystal X-ray diffraction. The results from single-crystal X-ray diffraction indicate that 1–5 are zero-dimensional (0D), zero-dimensional, one-dimensional (1D), and three-dimensional (3D) frameworks, respectively. In particular, 3 is twin crystal; 4 possesses of double-stranded chains; 5 crystallizes in orthorhombic space group P212121 with a helical chain in its structure. The luminescence properties and the magnetic properties of the five complexes were investigated. [Copyright &y& Elsevier]

Abstract: In this study, the high-intensity ultrasound was applied in the preparation of chiral polyurethane/CdS–SiO2 nanocomposites. The polyurethane/CdS–SiO2 nanocomposites were analyzed by powder X-ray diffraction, thermogravimetric analysis (TGA), TEM and SEM. The results indicated that the heat stability of the nanocomposites was improved in the presence of CdS–SiO2 core-shell nanoparticles. The infrared emissivity (8–14μm) study revealed that the nanocomposites possessed much lower infrared values compared with those of the neat polymers and nanoparticles, respectively. A possible mechanism of ultrasonic induced composite reaction was proposed based on the experimental results. [Copyright &y& Elsevier]

A phytochemical investigation on the flowers of Sophora davidii resulted in the isolation of three unusual matrine–adenine hybrids, sophovicines A–C, together with biogenetically related analogue sophocarpine. Their structures and absolute configurations were determined by NMR analysis, single-crystal X-ray diffraction, and electronic circular dichroism (ECD) data. Since sophovicines represent the first example of matrine-adenine hybrids, a putative biosynthetic pathway toward sophovicines A–C was proposed. In addition, computational molecular modeling suggested that compounds sophovicines B and C may have potent activities against human cytomegalovirus (HCMV). So, the inhibit effects of isolates on HCMV were evaluated. The results show that sophovicines B and C can inhibit HCMV replication effectively with IC 50 values of 7.12 and 7.32 μ M, respectively. Three unusual matrine–adenine hybrids were isolated from the flowers of Sophora davidii. Compounds 2 and 3 showed significant activity to inhibit HCMV replication. [Display omitted] • Three unusual matrine–adenine hybrids (1–3) were isolated from Sophora viciifolia. • A putative biosynthetic pathway toward 1–3 was proposed. • Compounds 2 and 3 showed significant activity to inhibit HCMV replication. • Brief structure-activity relationships were analyzed. [ABSTRACT FROM AUTHOR]

Nanosized cobalt aluminate (CoAl2O4) spinel powders have been prepared by a hydrothermal method. Titration of Co–Al mixed solution by NaOH solution yields a precursor with crystalline Co–Al-layered double hydroxide (LDH) and bayerite aluminum hydroxide (β-Al(OH)3) phases. After the precursor is hydrothermally reacted at 245 °C for 20 h, CoAl2O4 powders with a size of 65–75 nm and with a surface area of about 32.3 m2/g are prepared. The formation process has been investigated by X-ray diffraction (XRD), FT-IR, BET surface area measurement, and transmission electron microscopy (TEM) techniques. [Copyright &y& Elsevier]

A Ni/Ta bilayer is deposited on n-type 6H–SiC and then annealed at different temperatures to form an ohmic contact. The electrical properties are characterized by I–V curve measurement and the specific contact resistance is extracted by the transmission line method. The phase formation and microstructure of the Ni/Ta bilayer are studied after thermal annealing. The crystalline and microstructure properties are analyzed by using glance incident x-ray diffraction (GIXRD), Raman spectroscopy, and transmission electron microscopy. It is found that the transformation from the Schottky to the Ohmic occurs at 1050 °C and the GIXRD results show a distinct phase change from Ta2C to TaC at this temperature. A specific contact resistance of 6.5× 10−5 Ω·cm2 is obtained for sample Ni(80 nm)/Ta(20 nm)/6H–SiC after being annealed at 1050 °C. The formation of the TaC phase is regarded as the main reason for the excellent Ohmic properties of the Ni/Ta contacts to 6H–SiC. Raman and TEM data reveal that the graphite carbon is drastically consumed by the Ta element, which can improve the contact thermal stability. A schematic diagram is proposed to illustrate the microstructural changes of Ni/Ta/6H–SiC when annealed at different temperatures. [ABSTRACT FROM AUTHOR]