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New insights into 3D-oriented strain-induced crystallization of natural rubber/cellulose nanocrystal (NR/CNC) composites have been obtained by 2D wide-angle X-ray diffraction (2D-WAXD). Upon CNC content exceeding 10 wt%, the mechanical behavior of the material exhibits a yield point that resembles those observed in plastics. Taking into account the influence of filler content of CNCs and thickness, the three-dimensional orientation degree of NR crystallites can be quantitatively assessed. The formation of 3D NR crystallites can be established when the CNC content surpasses 10%, and concurrently, the degree of three-dimensional orientation of crystallites increases as thickness decreases. It was found that not only do CNCs enhance the confinement effect, leading to a decrease in the onset strain, but it is also beneficial for the formation of 3D-oriented strain-induced NR crystallites. The current study not only helps in the comprehensive understanding of the mechanism of 3D-oriented strain-induced NR crystallites by the constrained rigid filler network, but also provides the potential application of uniaxial tensile stretching in creating 3D functional materials. [ABSTRACT FROM AUTHOR]

The carrot has a high water content, and dehydration is an important means to extend its edible period and reduce storage and transportation costs. In the case of infrared (IR) drying, the porosity of the product is low and the structure is compact; the textural properties of the product are improved by using combined ultrasound and infrared (US-IR) drying; however, there is a lack of reports on the mechanism of this. Pectin has an important influence on the formation of the textural properties of fruit and vegetable tissues. In order to investigate the mechanism of the change in endogenous pectin properties in the carrot cell wall under US-IR drying on the improvement of the textural properties of the product, different fractions of pectins (water-soluble pectin, chelating pectin, alkali-soluble pectin) of the carrot were extracted, separated, and analysed. The thermal stability, component and content changes, Fourier infrared (FTIR), X-ray diffraction (XRD), esterification degree, molecular weight, monosaccharide composition, Ca ion content, and atomic force microscopy (AFM) of the pectins were determined. The results showed that the changes in the contents and properties of the carrot pectins under US-IR conditions had a positive effect on the improvement of the textural properties of the carrot tissues. [ABSTRACT FROM AUTHOR]

Revealing and clarifying the chemical reaction processes and mechanisms inside the batteries will bring a great help to the controllable preparation and performance modulation of batteries. Advanced characterization techniques based on synchrotron radiation (SR) have accelerated the development of various batteries over the past decade. In situ SR techniques have been widely used in the study of electrochemical reactions and mechanisms due to their excellent characteristics. Herein, the three most wide and important synchrotron radiation techniques used in battery research were systematically reviewed, namely X‐ray absorption fine structure (XAFS) spectroscopy, small‐angle X‐ray scattering (SAXS), and X‐ray diffraction (XRD). Special attention is paid to how these characterization techniques are used to understand the reaction mechanism of batteries and improve the practical characteristics of batteries. Moreover, the in situ combining techniques advance the acquisition of single scale structure information to the simultaneous characterization of multiscale structures, which will bring a new perspective to the research of batteries. Finally, the challenges and future opportunities of SR techniques for battery research are featured based on their current development. [ABSTRACT FROM AUTHOR]

In general, β-Ga2O3 films with (2¯01) out-of-orientation have been widely obtained and reported on (0001) sapphire substrates by various growth methods. In this paper, the unusual (3¯10)-oriented β-Ga2O3 films have been epitaxially grown on (0001) sapphire substrates with high crystal-quality under Ga-rich conditions by halide vapor phase epitaxy (HVPE). The out-of-plane epitaxial relationship as (3¯10) β-Ga2O3//(0001) α-Al2O3 has been confirmed by XRD and HRTEM analysis. Under most growth conditions, β-Ga2O3 films exhibit the coexistence of (3¯10) and (2¯01) out-of-plane orientation domains, and increasing the growth temperatures and HCl flow-rates can enhance the growth of (3¯10)-oriented β-Ga2O3. Off-angled (0001) sapphire substrates with off-angles (Δa) toward 〈112¯0〉 have been introduced to control the in-plane domains. It was indicated that the (2¯01)-oriented domains have been gradually eliminated with increasing the off-angles, and pure (3¯10)-oriented β-Ga2O3 films with the best crystal quality reported so far have been obtained while the off-angle was ∼7°. The decrease of the domain boundaries and defects caused by the in-plane rotational domains have led to the improvement of the crystal quality of the as-grown films. [ABSTRACT FROM AUTHOR]

Two mononuclear complexes, [(tfnb)3Ln(phen)] (Ln = Tb or Dy, tfnb = 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedione, phen = 1,10-phenanthroline), were isolated and structurally determined using single crystal X-ray diffraction techniques. The crystallographic data reveal that the two complexes are isostructural and adopt a trigonal dodecahedral geometry. The dysprosium complex exhibits a slow relaxation of the magnetization in the absence of a dc field. A combination of QTM, Raman and Orbach processes was considered in energy barrier fitting, giving the effective barrier Ueff = 193 K. The magnetic easy axis calculated using an electrostatic model follows the direction of the two tfnb− ligands in the trans position. [ABSTRACT FROM AUTHOR]

Advanced battery characterization techniques contribute to revealing and clarifying the chemical reaction processes and mechanisms inside the batteries. From atomic scale to nanoscale to long‐range periodic scale, from single scale to multiscale structure detection, this review comprehensively overviews the recent advances in battery characterization using in‐situ synchrotron XAFS, SAXS, XRD, and their combining techniques..By Weidong Cheng; Mengyuan Zhao; Yuecheng Lai; Xin Wang; Huanyan Liu; Peng Xiao; Guang Mo; Bin Liu and Yunpeng LiuReported by Author; Author; Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

This study accomplished the one-pot hydrothermal synthesis of cubic WO 3 nanocubes both in their pure form and doped with In (3 wt%, 5 wt%, and 7 wt%). The morphological and microstructural features of these cubic nanoblocks were assessed using various techniques including XRD, SEM, TEM, XPS, and BET analysis. Gas sensing tests were conducted on pure and In-doped WO 3 cubic nanoblocks, using triethylamine (TEA) as the test gas. Among all tested samples, the 5% In-WO 3 sensor showed the highest response to 50 ppm TEA (R a /R g = 11.2). The gas sensor additionally demonstrates rapid responses and recovery times, long-term stability, and outstanding selectivity, all of which are crucial for the construction of effective TEA gas sensors. The improvement of gas sensing performance may be due to the increase of oxygen vacancies and surface adsorbed oxygen after In-doping and the large specific surface area. • Pure WO 3 and In-doped WO 3 cubic nanoblocks were synthesized via a one-pot hydrothermal method. • At a lower operating temperature of 115 °C, In-doped WO 3 has higher response than pure WO 3. • In-doped WO 3 also has good repeatability, long-term stability and high selectivity. • The improvement of gas sensitivity may be mainly due to the increase of oxygen vacancy and surface adsorbed oxygen. [ABSTRACT FROM AUTHOR]

Two DMTCNQ (DMTCNQ = 2,5‐dimethyl‐7,7,8,8‐tetracyano‐p‐quinodimethane) and DETCNQ (DETCNQ = 2,5‐diethyl‐7,7,8,8‐tetracyano‐p‐quinodimethane) gadolinium complexes [Gd(DMTCNQ)2(CH3OH)(H2O)6][DMTCNQ]·4H2O (1) and [Gd(DETCNQ)(H2O)7][2DETCNQ] (2) were synthesized by reactions of GdCl3·6H2O with Li(DMTCNQ) or Li(DETCNQ). X‐ray diffraction analysis reveals that complexes 1 and 2 are discrete complexes. The central metal atom in 1 is coordinated by two DMTCNQ ligand radicals whereas that in 2 is coordinated by just one DETCNQ ligand radical. The adjacent molecules are connected by the intermolecular hydrogen bonds to form the two‐dimensional (2D) supramolecular layer structures, which are further packed into a three‐dimensional (3D) supramolecular architecture through the π–π interactions between ligand radicals in 1 and 2. Magnetic investigation indicates that the antiferromagnetic interactions between spin carriers exists in 1 and 2. [ABSTRACT FROM AUTHOR]

A new free carbon radical was obtained in a microwave‐assisted solvothermal reaction of the primary amine (1‐methyl‐1H‐benzo[d]imidazol‐2‐yl)methanamine with FeCl3⋅6 H2O in methanol at 140 °C. Through a combination of crystallography and electrospray ionization mass spectrometry, the reaction process was studied. The longest domino reaction includes 14 steps and forms up to 12 new covalent bonds (9 C−N and 3 C−C bonds) and 3 five‐membered heterocycles. For the first time, the homolytic cleavage of a C−O bond was used to synthesize a triarylmethyl radical. A free carbon radical was obtained in a domino reaction of a primary amine with FeCl3⋅6 H2O in methanol under solvothermal conditions. In this process, which was studied by crystallography and ESI mass spectrometry, the longest domino reaction features 14 steps, and methanol is sequentially activated; in addition, the homolytic cleavage of a C−O bond is proposed. [ABSTRACT FROM AUTHOR]

Utilization of microbes is one of the most promising methods to remediate potentially toxic metals (PTMs) from soil. In this study, a systematic investigation was conducted to study the influence of Bacillus subtilis on PTMs occurrence, fractionation, translocation, and accumulation in the rhizosphere soil of Maize (Zea mays L.) in pot experiments. B. subtilis showed strong effects on the fate and mobility of Pb, Sb, Ni, Zn, Cu, and Cr, and it also affected PTMs' distribution in the rhizosphere soil, maize growth, and microbial community structure. Results showed that it was easier for Zn to accumulate in maize roots than other PTMs. According to chemical fractionation, B. subtilis tended to immobilize Pb, Sb, Ni, Zn, and Cu in the rhizosphere soil. Compared with other PTMs, Cr tended to be more available and more mobile, which indicated a higher health risk to the eco-environment. These findings suggested that B. subtilis could be used as a geomicrobiological stabilizer to immobilize PTMs (Pb, Sb, Ni, Cu, Zn) in alkaline soils and decrease their uptake by plants, thus reducing the risks of a potential transfer into the food chain. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Sulfiding agent could effectively react with the supported Mo oxide to form intermediate thiosalts. • The usage of sulfiding agent could generate mononuclear and polynuclear ammonium thiosulfate. • The sulfiding conditions could modify the final morphology of active phase. • The large number of Mo nuclear would lead to the high stacking of MoS 2 slabs. • The catalyst with optimal Mo dispersion and ratios of edge sites to rim sites showed high HDS activity. Abstract The influence of sulfiding conditions in the ex-situ presulfidation process on the morphology and performances of CoMoS/γ-Al 2 O 3 catalysts was studied in details for hydrodesulfurization (HDS) of dibenzothiophene. Surface and bulk characterization using XRD, HRTEM, XPS, TPR and FT-IR confirmed that the sulfiding agent mixture of (NH 4) 2 S and elemental S effectively react with the supported Mo oxide to form intermediate thiosalts from mononuclear ammonium thiomolybdates to polynuclear ammonium thiomolybdates, namely the formed thiosalts from (NH 4) 2 MoS 4 to (NH 4) 2 Mo 2 S 12 and (NH 4) 2 Mo 3 S 13 ,which weaken the strong interaction between the γ-Al 2 O 3 support and Mo oxide, resulting in maximum sulfidation of Mo oxide species. Mo species tend to agglomerate as the number of Mo nuclear increases, which further induces significant changes in the morphology of MoS 2 particles. Such observation was further correlated with HDS activity and selectivity. The CoMoS/γ-Al 2 O 3 catalyst with (NH 4) 2 Mo 2 S 12 as intermediate exhibits suitable slab lengths and stacking numbers of MoS 2 slabs with optimal compromise between the Mo dispersion and ratios of edge sites to rim sites, and show the highest HDS activity. Therefore, a tailor-made catalyst with excellent HDS performance could be developed by adjusting the sulfiding conditions through ex-situ presulfidation method. [ABSTRACT FROM AUTHOR]

Abstract A carbon-containing FeCoCrNiAl 0.5 high entropy alloys (HEAs) with high tensile strength was fabricated by powder metallurgy (P/M) method. The P/M process includes gas atomization and hot extrusion of pre-alloyed HEA powder. The microstructural evolution and mechanical properties were systematically investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and tensile tests. The results showed that the gas-atomized HEA powder was of dual phase, including face centered cubic (fcc) phase and B2 phase. Hot extrusion caused the precipitation of M 23 C 6 carbides, the formation of dislocations and the refinement of microstructure. The as-extruded HEA exhibited a tensile strength as high as 1093 MPa and an elongation of ∼12.4%. The contributions of different strengthening mechanisms were quantitatively calculated, and it was found that the grain boundary strengthening and the dislocation strengthening are the main strengthening mechanism. Highlights • A novel, non-equiatomic HEA with fine and homogeneous microstructures was prepared by hot extruding pre-alloyed powder. • Formation M 23 C 6 carbide phases in f.c.c phase. • The as-extruded HEA exhibits a tensile strength of 1093 MPa, and a ductility of 12.4%. • The grain boundary strengthening and dislocation strengthening are main effecting mechanisms. [ABSTRACT FROM AUTHOR]

The sulfide oxygenation activities of both heptamolybdate ([Mo7O24]6−, [1]6−) and its peroxo adduct [Mo7O22(O2)2]6− ([2]6−) were examined in this contribution. [Mo7O22(O2)2]6− was prepared in a yield of 65% from (NH4)6[Mo7O24] (1a) upon treatment of 10 equiv. of H2O2 and structurally identified through single crystal X-ray diffraction study. (nBu4N)6[Mo7O22(O2)2] (2b) is an efficient catalyst for the sequential oxygenation of methyl phenyl sulfide (MPS) by H2O2 to the corresponding sulfoxide and subsequently sulfone with a 100% utility of H2O2. Surprisingly, (nBu4N)6[Mo7O24] (1b) is a significantly faster catalyst than 2b for MPS oxygenation under identical conditions. The pseudo-first order kcat constants from initial rate kinetics are 54 M−1 s−1 and 19 M−1 s−1 for 1b and 2b, respectively. Electrospray ionization mass spectrometry (ESI-MS) investigation of 1b under the catalytic reaction conditions revealed that [Mo2O11]2− is likely the main active species in sulfide oxygenation by H2O2. [ABSTRACT FROM AUTHOR]

Fluorescent thermometers display great advantages over conventional analytical methods in terms of its high sensitivity, fast response, simple operation, high spatial resolution, non-destructive inspection, as well as potential bioimaging applications. It has emerged as an effective analytical tool particularly for applications in large surface area, microfluids and biological systems. This review focuses on the recent research progress of fluorescence thermometers based on organic materials, including organic small molecules, macromolecules, and nanoassemblies. The importance of the thermometers, design principles, fluorescence response modes, as well as their biological applications are all thoroughly described in this review. Finally, the sensing performances of thermometers are analyzed highlighting the challenges which need to be addressed urgently and future directions in design and application of organic fluorescent thermometers. [ABSTRACT FROM AUTHOR]

Abstract: Fluorocarbons have important applications in industry, but are environmentally unfriendly, and can cause ozone depletion and contribute to the global warming with long atmospheric lifetimes and high global warming potential. In this work, the metal–organic framework UiO‐66(Zr) is demonstrated to have excellent performance characteristics to separate fluorocarbon mixtures at room temperature. Adsorption isotherm measurements of UiO‐66(Zr) display high fluorocarbon sorption uptakes of 5.0 mmol g−1 for R22 (CHClF2), 4.6 mmol g−1 for R125 (CHF2CF3), and 2.9 mmol g−1 for R32 (CH2F2) at 298 K and 1 bar. Breakthrough data obtained for binary (R22/R32 and R32/R125) and ternary (R32/R125/R134a) mixtures reveal high selectivities and capacities of UiO‐66(Zr) for the separation and recycling of these fluorocarbon mixtures. Furthermore, the UiO‐66(Zr) saturated with R22 and R125 can be regenerated at temperatures as low as 120 °C with excellent desorption–adsorption cycling stabilities. [ABSTRACT FROM AUTHOR]

Grain boundaries (GBs) are the most abundant structural defects in nanostructured nuclear fuels and play an important role in determining fission product behavior, which further affects the performance of nuclear fuels. In this work, cerium dioxide (CeO 2 ) is used as a surrogate material for mixed oxide fuels to understand gaseous fission product behavior, specifically Xe. First-principles calculations are employed to comprehensively study the behavior of Xe and trap sites for Xe near the Σ 3 (111)/[1 1 ¯ 0] grain boundary in CeO 2 , which will provide guidance on overall trends for Xe stability and diffusion at grain boundaries vs in the bulk. Significant segregation behavior of trap sites, regardless of charge states, is observed near the GB. This is mainly ascribed to the local atomic structure near the GB, which results in weaker bond strength and more negative segregation energies. For Xe, however, the segregation profile near the GB is different. Our calculations show that, as the size of trap sites increases, the segregation propensity of Xe is reduced. In addition, under hyper-stoichiometric conditions, the solubility of Xe trapped at the GB is significantly higher than that in the bulk, suggesting higher Xe concentration than that in the bulk. The results of this work demonstrate that the diffusion mechanism of Xe in CeO 2 is comparable to that in UO 2 . The diffusion activation energies of Xe atoms in the Σ 3 GB are lower than that in the bulk CeO 2 . These results suggest that the diffusivity of Xe atoms is higher along the GB than that in the bulk, which enhances the aggregation of Xe atoms near the GB. [ABSTRACT FROM AUTHOR]

High-Al-content Al x Ga 1−x N films with x varying from 0.33 to 0.79 were grown on GaN templates with the high temperature AlN (HT-AlN) interlayer by metal organic chemical vapor deposition (MOCVD). The best crystalline quality, among these Al x Ga 1−x N alloys, can be obtained for an AlN mole fraction x = 0.55, where the full-width at half-maximum of the Al 0.55 Ga 0.45 N ( 0002 ) diffraction peak was measured to be 259 arcsec by high resolution X-ray diffraction (HRXRD). The screw threading dislocation (TDs) density was 2 × 10 8 cm −2 evaluated by transmission electron microscope (TEM), which agreed with the calculations from Williamson-Hall plots. Moreover, cross-sectional TEM indicated that the HT-AlN interlayer could sufficiently reduce the threading dislocations (TDs) through generation of V trenches in the HT-AlN interlayer, since the TDs propagated along the V trenches, then bent into basal planes and annihilated with other dislocations. The study of optical properties indicated that obvious S-shape of temperature dependence on emission energy was observed for Al 0.55 Ga 0.45 N layers, which was attributed to exciton localization with energy (E loc ) ∼14.95 meV at 10 K resulting from potential fluctuation and band tail states. The time-resolved photoluminescence (TRPL) curves showed a bi-exponential decay at low temperature. The fast decay time implied the presence of the localized excitons enhancing radiative recombination, while the quite slow one was due to the dominance of trapping mechanisms originating from cation vacancy complexes and the V III -related complexes. [ABSTRACT FROM AUTHOR]

Manganese (IV) oxide (MnO) nano-sheets were synthesized using tetramethylamine, HO, and MnCl·4HO and used in suspension for removal of methylene blue (MB). Up to 95 % removal was achieved for MB concentrations less than 500 mg/L. The adsorption data fitted better with the Freundlich isotherm model than the Langmuir model, indicating a heterogeneous adsorption of MB on MnO nano-sheets. The maximum adsorption capacity of MnO nano-sheets was approximately 4300 mg/g, which is the highest yet reported. Suspensions of MnO nano-sheets aggregated as precipitates after adsorption of MB. Using a suite of analyses, including X-ray diffraction and X-ray photoelectron spectroscopy, the high adsorption capacity was mainly attributed to ion exchange, coordination, and a fishing-net effect. The term, 'fishing-net effect,' is proposed here for the first time, to explain the extremely high adsorption capacity of nano-sheets, which increased with increasing ionic strength and sorbate concentration. Our results demonstrate that dispersive MnO nano-sheets have a potential application in adsorption of organics from strongly basic solutions with high salinity. [ABSTRACT FROM AUTHOR]

Three novel inorganic–organic hybrid compounds based on different types of isopolymolybdates and CuII(bbx) complexes, namely, [Cu2II(bbx)2(β-Mo8O26)]·2H2O (1), [Cu2II(bbx)4(γ-Mo8O26)] (2) and H2[Cu2I(bbx)2(Mo2O8)] (3) (bbx = 1,3-bis(1-imidazolyl)benzene), have been successfully synthesized by adjusting the pH value under hydrothermal conditions. Compound 1, which was hydrothermally prepared at pH = 3.5, exhibits a unique 3D (2,5,6)-connected net with a (43·64·82·10)2(44·68·83)(4)2 topology, constructed by sexadentate Mo8O26)4− anions coordinated to CuII ions of one-dimensional [CuII(bbx)]n chains. When the pH value was adjusted to 4.5, a structurally different complex 2 was obtained. Compound 2 shows a 3D (2,5)-connected framework with an (86·124)2(8)5 topology, constructed by bidentate γ-(Mo8O26)4− polyanions linking 2D layers composed of [CuII(bbx)2]n. Moreover, when the pH value was adjusted to 7.5, an interesting complex 3 was obtained. Compound 3 shows a 2D (4)-connected framework with a (44·62) topology, constructed by bidentate (Mo2O8)4− polyanions linking [Cu2I(bbx)2]n ladder-like double-chains. The (Mo2O8)4− unit has never been observed before, which is composed of two rare distorted {MoO5} tetragonal pyramids connected via edge-sharing. All compounds were characterized by elemental analysis, TG analysis, powder X-ray diffraction, single-crystal X-ray diffraction analysis and solid diffuse reflectance spectroscopy. In addition, the electrochemical properties of compounds 1–3 have been investigated in 1 M H2SO4 aqueous solution. Moreover, compounds 1 and 3 have definite catalytic activities to activate peroxymonosulfate (PMS) in the reduction of methylene blue (MB). [ABSTRACT FROM AUTHOR]

Crystalline nanotube array would create great opportunity for novel electrical application. Herein we report the first example of a metal halide based crystalline nanotube array which is constructed from an unprecedented giant [PbII18I54(I2)9] wheel cluster, as determined by synchrotron Xray diffraction. The electrical properties of the single crystal were studied and the present compound shows typical semiconductivity and highly anisotropic conductivity. [ABSTRACT FROM AUTHOR]

A new diruthenium compound, Ru 2 (η 2 -D m AniF) 2 (μ-D m AniF) 2 (OAc)(O) ( 1 ), where D m AniF is N , N ′-di( m -methoxyphenyl)formamidinate, was isolated as a secondary product from the reaction between Ru 2 (D m AniF) 3 (OAc)Cl and K 2 CO 3 , and its formulation was established using both single crystal X-ray diffraction and high resolution mass-spectrometry techniques. Compound 1 has an S = 3/2 ground state, and exhibits an unusually large zero-field splitting ( D = 308 cm −1 ) as revealed by the measurement of temperature dependent magnetism. [ABSTRACT FROM AUTHOR]

A β-stabilized Ti–45Al–7Nb–0.4W–0.15B (at.%) alloy was hot deformed by uniaxial compression and the phase evolution during the compression was characterized with X-ray diffraction, scanning electron microscopy and electron probe microanalysis. The results show that modest deformation stress during hot compression restrains the γ → α transformation and the decomposition of β phase. The restrained γ → α transformation is a result of a modified equilibrium of the γ and α phases due to the applied stress, and the restrained β decomposition is a kinetic effect due to the decelerated diffusion of β-stabilizing elements caused by the compressive stress. [ABSTRACT FROM AUTHOR]

A new organic–inorganic hybrid tungstoantimonate, Na 4 [Ni 2 (apy)(H 2 O) 10 ] 1/2 [(Ni(Hapy)) 3 (Na(H 2 O) 2 ) 3 (SbW 9 O 33 ) 2 ]·23H 2 O (1) (apy = aminopyrazine), has been synthesized and fully characterized. Single crystal X-ray diffraction analysis indicates that the polyanion [(Ni(Hapy)) 3 (Na(H 2 O) 2 ) 3 (SbW 9 O 33 ) 2 ] 6 − displays a sandwich-type dimeric structure in which the Ni 2 + ions in the central belt are modified by aminopyrazine ligands. The contrast experiment analyses show that the existence of organic amine ligand is a key role to the formation of the stable Hervé-type tungstoantimonate containing trinuclear nickel(II) ions, which crystallized with dinuclear nickel complex constructed from an aminopyrazine bridging two [Ni(H 2 O) 5 ] 2 + ions as part of counterions. The variable-temperature magnetic measurements of 1 exhibit the weak antiferromagnetic exchange interactions among Ni(II) clusters in 1. [ABSTRACT FROM AUTHOR]

The 1D complex [(CuL0.5H2O) ⋅H2O] n ( 1) (H4L=2,2′-bipyridine-3,3′,6,6′-tetracarboxylic acid) undergoes an irreversible thermally triggered single-crystal-to-single-crystal (SCSC) transformation to produce the 3D anhydrous complex [CuL0.5] n ( 2). This SCSC structural transformation was confirmed by single-crystal X-ray diffraction analysis, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD) patterns, variable-temperature powder X-ray diffraction (VT-PXRD) patterns, and IR spectroscopy. Structural analyses reveal that in complex 2, though the initial 1D chain is still retained as in complex 1, accompanied with the Cu-bound H2O removed and new O(carboxyl)Cu bond forming, the coordination geometries around the CuII ions vary from a distorted trigonal bipyramid to a distorted square pyramid. With the drastic structural transition, significant property changes are observed. Magnetic analyses show prominent changes from antiferromagnetism to weak ferromagnetism due to the new formed Cu1-O-C-O-Cu4 bridge. The catalytic results demonstrate that, even though both solid-state materials present high catalytic activity for the synthesis of 2-imidazolines derivatives and can be reused, the activation temperature of complex 1 is higher than that of complex 2. In addition, a possible pathway for the SCSC structural transformations is proposed. [ABSTRACT FROM AUTHOR]

Six salts, ([(H2L1)(ZnCl4)] (1) (L1 = 1,1′-bis(benzimidazolyl)methane), [(H2L1)(CuCl4)]·H2O (2), [(H2L2)(ZnCl4)] (3) (L2 = 1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole), [( H2L2)(CuCl4)] (4), [(H2L3)(CuCl4)]·H2O (5) (L3 = 1- (4-(1H-benzimidazol-1-yl)butyl)-1H-benzimidazole), and [(H2L4)(ZnCl4)]·H2O (6) (L4 = 3,6-bis(imidazol-1-yl)pyridazine)), derived from bis(benzimidazole)/bis(imidazole) and metal(II) chloride dihydrate (zinc(II) chloride and copper(II) chloride dihydrate) were prepared and characterized by IR, X-ray structure analysis, elemental analysis, and TG analysis. The aromatic rings of the cations in all of the compounds are planar. X-ray diffraction analysis revealed that all the complexes have 3-D layer network structures built from hydrogen bonds between the cations and chlorometallate anions. Water molecules also play an important role in structure extension in2,5,and6. The arrangements of the anions and cations in their solid state are dominated not only by size and symmetry of the cations, but also by the non-covalent interactions existing in the crystal structures. Due to the weak interactions, the compound displays 3-D layer structure. [ABSTRACT FROM AUTHOR]

MnO/graphene oxide sheet composite (MnO/GOS) has been co-electrodeposited on the thermally treated carbon paper (TTCP) in phosphate buffer solution containing GOS and KMnO. The resulted samples have been characterized by scanning and transmission electron microscopy, Raman, X-ray diffraction, and X-ray photoelectron energy spectroscopy. The results show that the synthesized MnO may be δ-MnO and the morphology of MnO/GOS is very different from that of MnO, indicating that the introduction of GOS in electrolyte can influence the morphology during the deposition. The capacitive properties of the samples are investigated by using cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy. The specific capacitance of MnO for MnO/GOS can reach about 829 F g at discharged current density of 1.0 A g in 1 M NaSO aqueous solution, which is larger than that of MnO deposited on TTCP. The composite of MnO/GOS also exhibits excellent cyclic stability with a decrease of 18.5 % specific capacitance after 1,500 cycles. [ABSTRACT FROM AUTHOR]

Abstract: A non-enzymatic glucose sensor based on Cu nanowires (CuNWs) modified graphene transparent electrode (GTE) was developed as a substitute for indium tin oxide (ITO) electrode or glassy carbon electrode (GCE). GTE was prepared by four steps on the polyethylene terephthalate sheet, and then Cu nanowires were deposited onto GTE to achieve the hybrid electrode of CuNWs/GTE by spin-coating. The morphology and phase structures were characterized by scanning electron microscopy and X-ray power diffraction, respectively. The resistance and electrochemical properties of CuNWs/GTE were investigated by four point probe and cyclic voltammetry, respectively. Results indicated that the as-prepared sensor showed higher electrocatalytic activity toward glucose than pristine CuNWs and GTE; The sensor also showed wider linear response for glucose over concentrations ranging from 0.005 to 6.0mM with a sensitivity of 1100μA/(mMcm2), low detection limit of 1.6μM (S/N=3), and excellent anti-interference ability. More importantly, the as-prepared sensor had the similar or even better performances compared to those reported on ITO and GCE. [Copyright &y& Elsevier]

A series of polylactic acid (PLA) based nanocomposite fibrous membranes, including neat PLA, PLA/hydroxyapatite (HA) and PLA/HA/graphene oxide (GO), were fabricated via electrospinning method. The morphology and composition were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) respectively. The thermal stability was determined by thermogravimetric analysis (TGA). To estimate the cytocompatibility of asprepared PLA/HA/GO fibrous membrane, MC3T3-E1 cells were cultured, and the corresponding cell adhesion and differentiation capability were investigated by fluorescence microscopy, SEM and MTT test. The electrospun ternary PLA/HA/GO membrane exhibited three-dimensional fibrous structure with relatively rough surface morphology, which made itself ideal for cell attachment and proliferation in bone tissue regeneration. The fluorescence microscopy, SEM and MTT test confirmed that the PLA/HA/GO nanocomposite fibrous membrane created a proper environment for the seeding and proliferation of MC3T3-E1 cells. [ABSTRACT FROM AUTHOR]

Abstract: A molecularly imprinted polymers (MIPs) electrochemical sensor based on graphene (GR)–chitosan (CS) composite was constructed, finally used in dopamine (DA) measurement. The MIPs-GR sensor was prepared through electrodepositing DA–GR–CS composited film on the glass carbon electrode (GCE) and then removing DA from the film via electrochemical induced elution. X-ray diffraction (XRD), attenuated total reflection infrared spectroscopy (ATR-IR), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and differential pulse voltammetry (DPV) characterizations indicated that MIPs-GR/GCE formed an affinity film. Owing to excellent electronic properties, unique two-dimensional structure and large surface area of GR, the prepared sensor exhibited highly sensitive response to the oxidation of DA with enhanced current signal and short response time. The oxidation peak current of DPV was well-proportional to the concentration of DA in the range from 1.0×10−9 to 8.0×10−8 and 1.0×10−7 to 1.0×10−4 M. The developed sensor obtained a recovery of 96.7–105.0% in the DA determination of blood serum, resulted from the specific recognition to DA against the structural analog and coexisting interferences. [Copyright &y& Elsevier]

Abstract: A scale-up preparation of high-loading Pt/C (40wt%) to 3g per pot has been achieved with a microwave-assisted organic colloid method, followed by appropriate heat treatment in alternating atmospheres (nitrogen, oxygen, and hydrogen). The catalysts prepared in this work were characterized by thermogravimetric analysis, X-ray diffraction analysis, and transmission electron microscopy etc., and were found to be competitive with state-of-the-art HiSPEC 4100 Pt/C catalyst in terms of their activities towards the anodic oxidation of methanol and the cathodic reduction of oxygen. They also displayed better cathodic activity and stability in a hydrogen/air single-cell test. The particle size was as small as 2.3nm, which is smaller than HiSPEC 4100 Pt/C catalyst. The scale-up work reported in this paper provides a practicable method to achieve the volume production of a high-loading Pt/C catalyst for fuel cell applications. [Copyright &y& Elsevier]

Abstract: Three new ionic crystals based on Keggin anion and mixed-valent diruthenium tetracetate, [Ru2(CH3CO2)4(H2O)2]2[H n XW12O40]·[Ru2(CH3CO2)4(H2O)Cl]·12H2O {X = B, n = 3 (1); X = Si, n = 2 (2); X = Ge, n = 2 (3)}, have been prepared in acidic aqueous solution at about pH 3.0 by reaction of K4BW12O40·mH2O, K8SiW11O39·mH2O and K8GeW11O39·mH2O with diruthenium tetracetate Ru2(CH3COO)4Cl, respectively, and their structures were determined by X-Ray diffraction analysis. They are isostructural structure with the ratio of heteropolytungstate anion, Ru2(CH3CO2)4 + cation and neutral molecular Ru2(CH3CO2)4Cl of 1:2:1. The cyclic voltammetry in 0.5 M KNO3 aqueous solution at pH 3.0 show the respective electrochemical behaviors of the W-centers and Ru2-centers for these three complexes. Magnetic data analysis shows that diruthenium units display the ground state electronic configuration π*2 δ* with large positive D value. [Copyright &y& Elsevier]

Four new charge-transfer salts based on the ferrocenyl cationic donors ((CpFeCpCH2N+(CH3)3, CpFeCpCH2N+(CH3)2C2H5 and CpFeCpCH2P+(Ph)3)) and Lindqvist and Keggin polyoxoanion acceptors (([M6O19]2− (M = Mo, W) and [PMo12O40]3−)) with the ratio of ferrocenyl : polyoxoanions of 1 : 1, 2 : 1 or 4 : 1, [NBu4][CpFeCpCH2N(CH3)3][Mo6O19] (1), [CpFeCpCH2P(Ph)3]2[Mo6O19] (2), [CpFeCpCH2P(Ph)3]2[W6O19] (3) and [CpFeCpCH2N(CH3)2C2H5]4[PMo12O40] (4), were synthesized and characterized by IR, solid diffuse reflectance spectroscopy, fluorescence spectroscopy, electrospray ionization mass spectrometry (ESI-MS) and single crystal X-ray diffraction. X-Ray crystallographic studies reveal that 1 crystallizes in the monoclinic space group Pn, 2 and 3 are isomorphous and crystallize in the triclinic space group P1̅, and 4 crystallizes in the monoclinic space group P21/n. In 1–4, the ferrocenyl cations and the polyoxoanions are cocrystallized by Coulombic forces and C–H…O hydrogen bonds. Diffuse reflectance spectra indicate the presence of a broad charge-transfer band between 300 and 800 nm for 1–4. Studies of the photoluminescent properties show that formation of the charge-transfer salts 1–4 leads to the fluorescence quenching of the starting materials owing to the occurrence of an efficient electron transfer process from the ferrocenyl donors to POM acceptors. ESI-MS studies of 1–4 dissolved in acetonitrile show the formation of ion pairs of [NBu4][Mo6O19]−, [CpFeCpCH2N(CH3)3][Mo6O19]−, [CpFeCpCH2P(Ph)3][Mo6O19]−, [CpFeCpCH2P(Ph)3][W6O19]−, [CpFeCpCH2N(CH3)2C2H5]2[PMo12O40]2− and H[CpFeCpCH2N(CH3)2C2H5]2[PMo12O40]−. All the results provide the proof of the close interactions and the charge-transfer between the ferrocenyl and polyoxometalate moieties in 1–4 both in the solid state and in solution. [ABSTRACT FROM AUTHOR]

A novel complex of the zinc (II) nitrate with 1,5-diamino-3-oxapentane (Ldao), with the composition [Zn (Ldao) (NO3)2], was synthesized and characterized by elemental analyses and IR spectra. The crystal structure of the complex has been determined by the single-crystal X-ray diffraction. The molecular structure consists of an Ldao, two nitrate radicals, and a Zn (II) atom. In the complex, the Zn (II) atom is N, O, N’-chelated by an Ldao and is further coordinated by two nitrate anions in a distorted trigonal-bipyramidal geometry (τ = 0.66). The crystal structure is mainly stabilized by the intermolecular hydrogen bond. [ABSTRACT FROM AUTHOR]

The tridentate ligand 1,3-bis(benzimidazol-2-yl)-2-oxopropane (OBB) and its manganese(II) picrate complex, with composition [Mn(OBB)·(EtOH)2·(H2O)](pic)2·2EtOH (pic = picrate), have been synthesized and characterized. Single-crystal X-ray diffraction revealed that the Mn(II) ion is six-coordinated with a N2O4 ligand set, resulting in a distorted octahedral coordination geometry. The interaction of the ligand and its Mn(II) complex with calf thymus DNA was investigated by electronic absorption titration and viscosity measurements. The experimental results suggest that the ligand and its Mn(II) complex bind to DNA via an intercalation binding mode, and their binding affinity to DNA follows the order of complex > ligand. [ABSTRACT FROM AUTHOR]

Abstract: LiBH4+1/2MgH2 is a promising reactive hydride composite for hydrogen storage. In the present study, three Ce-based additives were used as catalysts to enhance the hydrogen storage performance of LiBH4+1/2MgH2 composites. The composites with Ce additives demonstrated significantly improved dehydrogenation kinetics and cyclic stability compared with the pure composite. X-ray diffraction and scanning electron microscopy analyses clearly revealed the phase transitions and morphological evolution during the hydriding-dehydriding cycling. The composites with Ce-based additives displayed stable nanostructures, in contrast to the rapid microstructural deterioration in the uncatalyzed composite. The CeB6 formed in the composites had a particle size of 10 nm after five cycles. It may act as the nucleus for MgB2 formation during dehydrogenation and thus account for the structural and performance stability of the composites upon cycling. [Copyright &y& Elsevier]

Four new Cu(ii) complexes {[Cu4(bpy)4(OH)4(H2O)2]}(NO3)2(C7H5O2)2·6H2O 1, {[Cu4(bpy)4(OH)4(H2O)2]}(NO3)2(C5H6O4)·8H2O 2, {[Cu4(bpy)4(OH)4(H2O)2]}(C5H6O4)2·16H2O 3and {[Cu6(bpy)6(OH)6(H2O)2]}(C8H7O2)6·12H2O 4were synthesized (bpy = 2,2′-bipyridine, H2(C5H6O4) = glutaric acid, H(C7H5O2) = benzoic acid, H(C8H7O2) = phenyl acetic acid). The building units in 1–3are the tetranuclear [Cu4(bpy)4(H2O)2(μ2-OH)2(μ3-OH)2]4+complex cations, and in 4the hexanuclear [Cu6(bpy)6(H2O)2(μ2-OH)2(μ3-OH)4]6+complex cations, respectively. The tetra- and hexanuclear cluster cores [Cu4(μ2-OH)2(μ3-OH)2] and [Cu6(μ2-OH)2(μ3-OH)4] in the complex cations could be viewed as from step-like di- and trimerization of the well-known hydroxo-bridged dinuclear [Cu2(μ2-OH)2] entities viathe out-of-plane Cu–O(H) bonds. The complex cations are supramolecularly assembled into (4,4) topological networks viaintercationic ππ stacking interactions. The counteranions and lattice H2O molecules are sandwiched between the 2D cationic networks to form hydrogen-bonded networks in 1–3, while the phenyl acetate anions and the lattice H2O molecules generate 3D hydrogen-bonded anionic framework to interpenetrate with the (4,4) topological cationic networks with the hexanuclear complex cations in the channels. The ferromagnetic coupling between Cu(ii) ions in the [Cu4(μ2-OH)2(μ3-OH)2] cores of 1–3is significantly stronger viaequatorial-equatorial OH−bridges than viaequatorial-apical ones. The outer and the central [Cu2(OH)2] unit within the [Cu6(μ2-OH)2(μ3-OH)4] cluster cores in 4exhibit weak ferromagnetic and antiferromagnetic interactions, respectively. Results about i.r. spectra, thermal and elemental analyses are presented. [ABSTRACT FROM AUTHOR]

A five-coordinate cadmium(II) complex with 1,3-bis(1-benzylbenzimidazol-2-yl)2-thiapropane (L), [Cd(L)Br2] · DMF, has been synthesized and characterized by elemental analysis, electrical conductivities, IR, and UV-Vis spectral measurements. The crystal structure of the complex has been determined by single-crystal X-ray diffraction. The Cd(II) is five-coordinate with two nitrogens and a sulfur from one ligand, and two bromides. The N2SBr2 donors are in a distorted square-pyramidal geometry (τ = 0.32). Electronic absorption titration spectra, EB (ethidium bromide) competitive experiment, and viscosity measurement indicated that the complex can bind to DNA via intercalation. [ABSTRACT FROM AUTHOR]

A seven-coordinate manganese(II) complex with the tripod tetradentate ligand tris(N-methylbenzimidazol-2-ylmethyl)amine (Mentb), [Mn(Mentb)(salicylate)(DMF)](ClO4) ⋅ (DMF), was synthesized and characterized by elemental, electrical conductivity, infrared, and UV-Vis spectral measurements. The crystal structure of the complex has been determined by single-crystal X-ray diffraction. MnII is bonded to a Mentb, a salicylate and dimethylformamide through four nitrogens and three oxygens, resulting in seven-coordination. Cyclic voltammograms of the complex indicate a quasi-reversible Mn3+/Mn2+ couple. The X-band electron paramagnetic resonance spectrum exhibits a six-line manganese hyperfine pattern with g = 2, A = 93, confirming that the material is high-spin Mn(II). [ABSTRACT FROM AUTHOR]

Abstract: A microwave-assisted hydrothermal method was employed to synthesize nitrogen doped titania nanoparticles. Due to the high heating efficiency of microwave, rapid synthesis could be achieved in comparison with the conventional oven. Mixed crystal lattice was found existing in the obtained product, and the phase transformation behaviour under calcination was studied by XRD measurement together with Raman spectroscopy in details. The obtained nitrogen doped titania showed high specific surface area, about 300m2 g−1. Photocatalytic activity in destructing NO x gas by the prepared sample exceeded that of commercial titania (P 25) or nitrogen doped titania synthesized by conventional hydrothermal method, under both visible-light and ultraviolet-light irradiation. [Copyright &y& Elsevier]

A new family of heteropolytungstate complexes (NH4)21[Ln(H2O)5{Ni(H2O)}2As4W40O140]·xH2O(Ln=Y, Ce, Pr, Nd, Sm, Eu, Gd) were prepared by the reaction of Na27[NaAs4W40O140]·60H2O with NiCl2·6H2O and Ln(NO3)3·xH2O at pH≈4.5. The crystal structures of (NH4)21[Gd(H2O)5{Ni(H2O)}2As4W40O140]·51H2O was determined by X-ray diffraction analysis and element analysis. The compound crystallizes in the monoclinic space group P21/n with a=19.754(3), b=24.298(4), c=39.350(6) A˚, β=100.612(3)°, V=18564(5) A˚3, Z=2, R1(wR2)=0.0544(0.0691). The central site S1 and two opposite sites S2 of the big cyclic ligand [As4W40O140]28− are occupied by one Ln3+and two Ni2+, respectively, each site supply four Od coordinating to metal ion, another one water molecule and other five water molecules coordinate, respectively, to Ni2+and Ln3+. Polyanion [Ln(H2O)5{Ni(H2O)}2As4W40O140]21− has C2v symmetry. IR and UV–vis spectra of [NaAs4W40O140]27− of the title compounds are discussed. [Copyright &y& Elsevier]

A convenient method was developed to synthesize potassium borohydride by a mechano-chemical reaction of saline hydrides with dehydrated borates with a planetary ball mill. Among the tested saline hydrides, MgH2 was the most effective reactant for borohydride formation. In order to improve the borohydride yield, it was necessary to add an excessive amount of MgH2. When a 35% excess of MgH2 was added, potassium borohydride yield reached 100%. The borohydride formation was strongly dependent on the water content in reactants. When the water content in KBO2 samples was over 24.8 wt.% (equivalent to KBO2·1.5H2O), no borate was converted into borohydride by the mechano-chemical reaction. [Copyright &y& Elsevier]

Two types of linear tetranuclear heterometallic clusters with identical formulas but different structures have been successfully synthesized and structurally characterized. Their photoluminescent and magnetic properties have been investigated. • Eight linear tetranuclear heterometallic clusters have been successfully synthesized and structurally characterized. • They possess identical formulas but different structures. • Their photoluminescent and magnetic properties have been investigated. Eight 3d-4f heterometallic complexes, Ln 2 Ni 2 (3,4-DCB) 10 (phen) 2 [Ln = Nd (1), Sm (2), Eu (3), Gd (4), Tb (5), Dy (6), Er (7) and Yb (8)], were successfully prepared through the self-assembly reactions of Ln(NO 3) 3 · n H 2 O, NiCl 2 ·6H 2 O, 3,4-dichlorobenzoic acid (3,4-HDCB), NaOH and 1,10-phenanthroline (phen) under solvothermal conditions. These eight complexes were characterized by single-crystal X-ray diffraction, elemental analysis, FT-IR, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA). Complexes 1 – 8 have identical formulas, but different molecular structures. Complexes 1 – 6 and 7 – 8 are isostructural. In 1 – 8 , the 3,4-DCB anions link the Ni(II) and Ln(III) ions by different coordination modes to form two types of linear tetranuclear heterometallic clusters. Adjacent tetranuclear clusters are connected by π–π interactions between 3,4-DCB and phen into a one-dimensional (1D) supramolecular chain. The photoluminescent properties of 3 and the magnetic properties of 1 – 2 and 4 – 8 were investigated. [ABSTRACT FROM AUTHOR]

InxGa1-xN alloys with low indium composition x in the range 0.13 ≤ x ≤ 0.23 are systematically studied mainly based on a Raman scattering technique. Scanning electron microscopy and x-ray diffraction results show that our samples can be divided into two groups: pseudomorphic (0.13 ≤ x ≤ 0.16) and relaxed (0.18 ≤ x ≤ 0.23). The prominent enhancement of A1 longitudinal-optical (LO) mode is found with 325nm laser excitation. For pseudomorphic samples, the frequencies of A1 (LO) phonons agree well with the theoretical predictions, which verifies that the samples are fully strained. For relaxed InxGa1-xN samples, a linear dependence of the A1 (LO) mode frequency is obtained: Ω0(x) = (740.8 ± 3.3) -- (143.1 ± 16.0)x, which is the evidence of one-mode behavior in InxGa1-xN ternary alloys. Residual strains in these partially relaxed samples are also evaluated. [ABSTRACT FROM AUTHOR]

Abstract: A new sandwich-type polyoxometalate based on Keggin-type monolacunary anion, [Zr(α-BW11O39)2]14− was synthesized and characterized by IR spectroscopy, UV electronic spectroscopy, cyclic voltammetry and single-crystal X-ray diffraction. This is the first report of crystal structure for the sandwich Keggin-type polyoxotungstoborate. [Copyright &y& Elsevier]

Domino Reactions. In their Communication on page 3748 ff., M.‐H. Zeng et al. describe the synthesis of a free carbon radical through the domino reaction of a primary amine with FeCl3⋅6 H2O in methanol under solvothermal conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] The simple preparation of mesoporous NiS 2 //MoS 2 composite catalyst through a one-pot solvothermal method is presented. The improvement of the specific surface area (220 m2/g) and the construction of the porous structure are realized by this method in the case of no support. The organics acts as a microscopic binder contribute to uniform stacking of MoS 2 with NiS 2 clusters. The composite structure including NiS 2 and MoS 2 was obtained (proved by XRD, XPS, TEM, IR, UV–vis and RAMAN) and changed the microelectronic environment of the active metal surface (DFT calculation). The mesoporous NiS 2 //MoS 2 catalyst (Ni 1 Mo 1 -200) showed an excellent hydrodesulfurization performance of dibenzothiophene (DBT conversion: 78 % at 260 °C) and a high ratio of direct desulfurization pathway (S DDS/HYD = 16.6) at a low reaction temperature. By combining the characterization and theoretical calculation results, the advantages of this NiS 2 //MoS 2 composite structure in synergistic catalysis was further confirmed. [ABSTRACT FROM AUTHOR]