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Abstract In the past four years, transition metal vanadates have received booming attention as anode materials for lithium ion batteries (LIBs) due to their outstanding specific capacities, decent cycling performance and superior rate properties. Among them, Co 3 V 2 O 8 is the most reported species. However the cobalt is expensive, thus the replacement of cobalt would be a favorable route. So far, mixed vanadates have been rarely reported because of the remarkable difficulty in fabrication, among which cobalt/nickel mixed vanadates are the most attractive. In this work, a facile and green hydrothermal method with organic linker has been developed, to achieve modulated cobalt/nickel mixtures. It was corroborated by the X-ray diffraction (XRD) patterns and cyclic voltammetry (CV) profiles that single phase of cubic Co 3 V 2 O 8 crystal structures were formed. The mixed vanadates demonstrated ultrahigh reversible capacity of over ∼1800 mAh/g at the current density of 0.2 A/g after ∼200 cycles and superb rate capability of ∼600 mAh/g at 4 A/g. The enhanced electrochemical performances of the higher-nickel-ratio indicated their considerable potential as high-capacity anode materials in LIBs. Graphical abstract Image 1 Highlights • Cobalt/nickel mixed vanadates were obtained via one-step and green hydrothermal process. • The mixed vanadates maintain the cubic crystal of Co 3 V 2 O 8 with nickel doping. • Higher concentration of doped nickel induced uniform nanoparticles smaller than 100 nm. • CoNi 2 V 2 O 8 delivered reversible capacity of 1800 mAh/g at 0.2 A/g and 600 mAh/g at 4 A/g. [ABSTRACT FROM AUTHOR]

Abstract: Liquid lubricant is widely used in macro sheet forming. However, it is not wise to use liquid lubricant for micro sheet forming because of friction size effects. Three kinds of solid lubrication films were proposed to treat SKD11 sample in this study. TiN and diamond-like carbon (DLC) films were fabricated by plasma immersion ion implantation and deposition (PIIID). However, MoS2 film was fabricated by magnetron sputtering. Raman spectrum, X-ray diffraction (XRD), atomic force microscope (AFM), ball-on-disc test and scratch test were used to investigate the structure, tribological property, and adhesion strength of the films. The results showed that comprehensive properties of the DLC film were much better than TiN and MoS2 films and can be chosen as a suitable lubricant for micro sheet forming. To further investigate the effect of DLC film to micro sheet forming, a micro deep drawing experiment was carried out by using a DLC film-coated micro blanking-deep drawing multiple operation mould. The results showed that the limiting drawing coefficient (LDC) and drawing force were dramatically decreased. [Copyright &y& Elsevier]

Abstract: Three new tetranuclear nickel(II) complexes of general formula [Ni4(L)2(N3)2(CH3COO)2(CH3O)2]2·xCH3OH·yH2O (HL=HL1, HL2 and HL3; x =0, y =1 for 1; x =2, y =0 for 2 and x =2, y =4 for 3) were synthesized and characterized by single crystal X-ray diffraction and magnetic measurements. Single crystal X-ray studies reveal that all three complexes exhibit similar tetranuclear face-shared defective double-cubane structure, having azido-, alk/phenoxido- and acetato-bridges. Magnetic susceptibility measurements on the complexes in the range of 300–2K indicate ferromagnetic coupling between the metal ions. The slightly different magnetic behaviors observed are probably caused by subtle structural differences between the respective [Ni4O4N2] cores induced by ligand variation. [Copyright &y& Elsevier]

A novel samarium(III) polymer, [Sm(CHCOO)(CHOH)]·CHOH ( 1) has been synthesized and characterized by single crystal X-ray diffraction and magnetic measurements. Polymer 1 crystallizes in monoclinic space group P2(1)/ c, with a = 15.1247(6), b = 18.3351(7), c = 21.1266(6) Å, β = 126.830(2)°, V = 4689.4(3) Å, and Z = 4. Single crystal X-ray analysis reveals a chain-like structure of 1 consisted of alternating eight- and nine-coordinate Sm(III) ions bridged by benzoate ligands in different coordination modes. A treatment of the variable-temperature magnetic susceptibility using an expression deduced from free-ion approximation and molecular field theory suggests the existence of a weak antiferromagnetic coupling between the samarium ions. Graphical Abstract: A novel one-dimensional samarium polymer containing alternating eight- and nine-coordinate Sm(III) ions has been generated by incorporating benzoic acid in three different binding modes in its deprotonated state.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: A novel polymeric carboxylato-bridged praseodymium(III) complex of fumarate, [Pr2(fum)3(H2O)4]·5H2O (fum, fumarate dianion) has been synthesized and characterized by single-crystal X-ray diffraction studies, magnetic measurements and thermal studies. Single crystal X-ray structural determination reveals that it is a new porous three dimensional pillared layer framework with 1D channel for the accommodation of tetrameric water clusters. A preliminary treatment of the variable-temperature magnetic susceptibility using an expression including the ligand field effects and molecular field approximation leads to zJ′=−1.60cm−1, Δ =0.5cm−1 and g =0.84, suggesting the existence of a weak antiferromagnetic coupling between the praseodymium ions. [ABSTRACT FROM AUTHOR]

Abstract: A novel Coordination polymer, [{Er4(μ3-OH)4 (bpdc)4(H2O)6}2] (H2O)16.5 (1) was obtained by hydrothermal reaction. The cubane-like [Er4(μ3-OH)4]8+ as building block, it was further assembled into two-dimensional network structure through the linkage of 2,2′-bipyridine-3,3′-dicarboxylate (bpdc) with four different coordination modes. The magnetic property of the compound was discussed further. [Copyright &y& Elsevier]

Abstract: Four lanthanide coordination polymers, [{Ln2(bpdc)3(phen)2(H2O)2}·(H2O)6] n (Ln=Sm (1); Eu (2); Gd (3), Tb (4)), were self-assembled from 2,2′-bipyridine-3,3′-dicarboxylic acid (H2bpdc),1,10-phenanthroline(phen) and corresponding lanthanide oxides by hydrothermal synthesis. Compounds 1–4 are found to be isomorphous and isostructural. Single-crystal X-ray diffraction studies show that compounds 1–4 are all of one-dimensional zigzag chain structures and extend to two-dimensional networks through π–π interactions and hydrogen bonds. The pyridyl nitrogen atoms of the 2,2′-bipyridyl unit in the bpdc ligand are uncoordinated in an anti-conformation along the central C–C bond of the ligand. Thermogravimetric analysis of 1–4 showed an obvious thermal stability indicating that the coordination habit of the metal ions with bpdc and phen has an effect on the overall framework. Photoluminescence measurement indicates that compound 2 and compound 4 are strong red and green emitters, respectively. [Copyright &y& Elsevier]

Abstract: Two lanthanide coordination polymers, [{Ln2(bpdc)3(phen)2(H2O)2}·(H2O)6] n (Ln=Dy (1); Ho (2)) were obtained from 2,2′-bipyridine-3,3′-dicarboxylic acid (H2bpdc), 1,10-phenanthroline (phen) and corresponding lanthanide oxides by hydrothermal synthesis. Polymers 1–2 are found to be isostructural. Single-crystal X-ray diffraction shows that 1–2 are all one-dimensional zigzag chain structures and extend to two-dimensional networks through π–π interactions and hydrogen bonds. Thermogravimetric analysis of 1–2 displays a considerable thermal stability. The variable-temperature magnetic susceptibility of both compounds was measured. Photoluminescence measurement indicates that 1 is a strong yellow emitter. [Copyright &y& Elsevier]

To optimize the mechanical properties of Ti(C,N)-based cermets used as tool materials, the cermets with different Ni–Co binder contents and Co/(Ni + Co) weight ratios were prepared. The effects of metal binder content and Co/(Ni + Co) ratio on the microstructure and mechanical properties of Ti(C,N)-based cermets were investigated by scanning electron microscope (SEM) with energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and measuring the transverse rupture strength (TRS), Vickers hardness ( HV ) and fracture toughness ( K IC ). The experimental results reveal that increasing Ni–Co binder content can increase the thickness of rim phases by improving the solid solution reaction and the wetting of hard phases. The cermets with 25 wt.% binder addition present good comprehensive mechanical properties, which is attributed to the moderate rim phases and uniformly distributed Ti(C,N) grains. The Co/(Ni + Co) weight ratios in binder have a great influence on the grain sizes and microstructure features of Ti(C,N)-based cermets, in virtue of the synergic effects between the wettability of Co and the solubilizing capacity of Ni on hard phases. The cermets with pure Co as binder exhibit optimal mechanical properties with a TRS of 1767 ± 81 MPa, a hardness of 12.26 ± 0.10 GPa and a K IC of 8.40 ± 0.47 MPa m 1/2 , which meet the requirements for tool materials. And the cermets with a Co/(Ni + Co) ratio of 0.2 have the second best mechanical properties with a TRS of 1848 ± 201 MPa, a hardness of 11.12 ± 0.40 GPa and a K IC of 9.43 ± 0.54 MPa m 1/2 , in which the lower hardness can be further improved by optimizing the compositions and sintering process. [ABSTRACT FROM AUTHOR]

Reactions of lanthanide(III) perchlorate (Ln = Dy, Tb, and Gd), nickel(II) acetate, and ditopic ligand 2-(benzothiazol-2-ylhydrazonomethyl)-6-methoxyphenol (H2L) in a mixture of methanol and acetone in the presence of NaOH resulted in the successful assembly of novel Ln2Ni2 heterometallic clusters representing a new heterometallic 3d-4f motif. Single-crystal X-ray diffraction reveals that all compounds are isostructural, with the central core composed of distorted [Ln2Ni2O4] cubanes of the general formula [Ln2Ni2(μ3-OH)2(OH)(OAc)4(HL)2(MeOH)3](ClO4)·3MeOH [Ln = Dy (1), Tb (2), and Gd (3)]. The magnetic properties of all compounds have been investigated. Magnetic analysis on compound 3 indicates ferromagnetic Gd⋯Ni exchange interactions competing with antiferromagnetic Ni⋯Ni interactions. Compound 1 displays slow relaxation of magnetization, which is largely attributed to the presence of the anisotropic DyIII ions, and thus represents a new discrete [Dy2Ni2] heterometallic cubane exhibiting probable single-molecule magnetic behavior. [ABSTRACT FROM AUTHOR]

Two new dysprosium(III) coordination compounds, namely, [Dy4(HL)4(C6H4NH2COO)2(μ3-OH)4(u-OH)2(H2O)4] ·4CH3CN· 12H2O (1) and Dy8(HL)10(C6H4NH2COO)2(μ3-OH)8(OH)2(NO3)2(H2O)4] (2), have been synthesized from the Schiff-base ligand 2-{[(2-hydroxy-3-methoxyphenyl)methylidene]amino}benzoic acid (H2L) and dysprosium chloride (1) or dysprosium nitrate (2). Single-crystal X-ray diffraction studies reveal that compound 1 exhibits a tetranuclear cubane-like structure and that 2 is an octanuclear, bis-cubane complex. The [Dy4(μ3-OH)μ] cubane cores of 1 and 2 are structurally related; however, the magnetic properties of 1 and 2 are drastically different. Indeed, 2 shows slow relaxation of magnetization while no out-of-phase alternating current (ac) signal is noticed for 1. These significant disparities are most likely due to the different M-O-M angles observed for the respective cubane cores. [ABSTRACT FROM AUTHOR]

Five new complexes based on rare-earth-radical [Ln(hfac)3(NIT-5-Br-3py)]2 (Ln=Pr (1), Sm (2), Eu (3), Th (4), Tm (5); hfac = hexafluoroacetylacetonate; NIT-5-Br-3py = 2-(4,4,5,5-tetramethyl-3-oxylimidazoline-1 -oxide)-5-bromo-3-pyddine) have been synthesized and charactetized by X-ray crystal diffraction. The single-crystal stnjctures show that these complexes have similar slnictures, in which a NIT-5-Br-3py molecule acts as a bridging ligand linking two Ln(Ill) ions through the oxygen atom of the N-O group and nitrogen atom from the pytidine ting to form a four-spin system. Both static and dynamic magnetic properties were measured for complex 4, which exhibits single-molecule magnetism behavior. [ABSTRACT FROM AUTHOR]

Two novel three-dimensional (3D) 3d–4f mixed complexes [Ln-(H2O)4][Ni2TTHA(SCN)2]·H3O+ [Ln = Pr (1), Ce (2); H6TTHA = triethylenetetraaminehexaacetic acid], based on the building blocks of [Ni2TTHA(SCN)2]4-, were synthesized and characterized by X-ray crystal diffraction and magnetic properties. The single-crystal structures show that these complexes form a 3D framework, comprised of an unusual infinite one-dimensional chain based on heterometallic Ln2Ni2 rings. The temperature-dependent magnetic susceptibilities were analyzed by an approximate model, leading to g = 2.06. Δ = 2.83, zJ′ = -0.6 cm-1 for complex 1 and g = 2.07, Δ = 1.00, zJ′ = -0.5 cm-1 for complex 2. [ABSTRACT FROM AUTHOR]