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Manipulating the synergy between magnetic and optical characteristics in a predictable manner by an external stimulus is a highly desirable option to develop smart materials for advanced applications such as information processing and storage in multifunctional devices. Herein we report dinuclear complexes Ln2L2(depma2)Cl2 (1-Ln, Ln = Dy, Gd; H2L = N1,N3-bis(salicylideneimino)diethylenetriamine, depma2 = photodimerized 9-diethylphosphonomethylanthracene) where the lanthanide ions possess pseudo-D5h geometries with five equatorial positions occupied by L2− and the axial positions by depma2 and the Cl− anion. depma2 acts as a bridge between the equivalent LnIII ions and can be opened and closed upon heating and light irradiation. 1-Ln experience consecutive structural transformations, first separation of the depma2 at ca. 170 °C and second elimination of chloroethane at ca. 250 °C, accompanied by a synergetic switch of the photoluminescence and magnetic dynamics for 1-Dy. [ABSTRACT FROM AUTHOR]

Bimetallic MOF precursors can produce a homogeneous distribution of mixed-metal oxides after calcination, and thus may provide high efficiency as electrocatalysts in the water splitting process. We designed a layered bimetallic-organophosphonate containing Ir, Co and P because the metal-oxides are well-known for their efficiency in the oxygen-evolution reaction (OER), especially when the phosphate acts as a proton carrier. We describe the structure of the MOF and characteristics of the calcined form, which has outstanding OER characteristics in 1.0 M KOH with an overpotential of 317.7 mV at 10 mA cm−2 and a low Tafel slope of 59.1 mV dec−1. [ABSTRACT FROM AUTHOR]

In this paper, we present the synthesis of Ni nanoparticles supported on graphene (Ni/G) using graphene oxide (GO) and Ni2+ ions as starting materials. GO is mixed with NiCl2 solution and treated by hydrazine. Hydrazine both reduces the GO and forms a complex with nickel(ii). A treatment in the tubular furnace allows decomposing the nickel-hydrazine complex into Ni metallic nanoparticles as well as further reducing the GO into graphene. The materials are characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and thermogravimetry–mass spectrometry as well as tested for methanol electrooxidation in alkaline medium. [ABSTRACT FROM AUTHOR]

Direct melt/solid polycondensation of lactic acid (LA) was carried out to obtain high molecular weight poly(lactic acid) (PLA) by a process using various catalysts in the first-step melt polycondensation, and followed solid polycondensation by using p-toulenesulfonic acid monohydrate (TSA) as the catalyst in the second step. Effects of various catalysts and reaction temperature on the molecular weight and crystallinity of resulting PLA polymers were examined. It was shown that SnCl2·2H2O/TSA, SnCl2·2H2O/succinic anhydride, and SnCl2·2H2O/maleic anhydride binary catalysts should be effective binary catalysts to obtain high molecular weight PLA of more than 1.2 × 105. A conventional melt spinning method was used to spin PLA fibers, which displayed tensile strength of (382.76 ± 1.41) MPa and tensile modulus of (4.36 ± 0.07) GPa. [ABSTRACT FROM AUTHOR]

Ultrafine polyacrylonitrile (PAN) fibers, as a precursor of carbon nanofibers, with diameters in the range of 220–760 nm were obtained by electrospinning of PAN solution using N, N-dimethyl formamide (DMF) as solvent. Morphology of the nanofibers for varying concentration and applied voltage was investigated by field emission scanning electron microscopy (FESEM). The thermal properties and structural changes during the oxidative stabilization process were primarily investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and Fourier transform infrared (FT-IR) and Raman spectroscopy. The nanofiber diameters increase as the applied voltage is increased and they also increase with an increase in the concentration of the polymer solution. It was also concluded that the electrospun fibers displayed a very sharp exothermic peak at 297.34 °C. A transition temperature observed by FT-IR and Raman was approximately 300 °C, which was closely consistent with the results of DSC and TGA studies. It was also found that oxidative stabilization in air was accompanied by a change in color of nanofibers webs. [ABSTRACT FROM AUTHOR]

PMMAIPAN core/shell microspheres were synthesised by polymerising methyl methacrylate (MMA) or acrylonitrile(AN) at 75 °C for 5 h in a soapless emulsion system, using ammonium persulfate (APS) as a radical initiator. It has been shown that in the first-stage reaction the initiator APS significantly accelerated the reaction rate. However, when the APS concentration reached 0.9% (based on the amount of the monomers), this tendency lessened. In the second-stage core/shell reaction, the effect of initiator on reaction rate was not so pronounced. Transmission electron microscope (TEM), fourier transform infrared (FT-IR), thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) were used to characterise the structure and properties of seeded PMMA core and/or PMMA/PAN core/shell polymers. The core/shell morphology was clearly displayed and the diameter of the core is ca. 350 nm whereas the shell thickness was ca. 100 nm. Both the PMMA core and the PMMA/PAN core/ shell polymers had weak and strong endothermic peaks when heated in the range of 340-390 °C, but the latter showed a characteristic exothermic peak which corresponded with the crosslinking reaction of polyacrylonitrile macromolecules at ca. 600 °C. A mixture was obtained by blending the core/shell polymers with high density polyethylene, then spinning to form composite fibres, which were thermally stabilised in air at 180 °C for 1 h and carbonised in nitrogen at 1000 °C to obtain nanometre-sized carbon fibres. [ABSTRACT FROM AUTHOR]

Since knowledge of the structure and elastic properties of Ta at high pressures is critical for addressing the recent controversies regarding the high-pressure stable phase and elastic properties, we perform a systematical study on the high-pressure structure and elastic properties of the cubic Ta by using the first-principles method. Results show that the initial body-centered cubic phase of Ta remains stable even up to 500 GPa and the high-pressure elastic properties are excellently consistent with the available experimental results. Besides, the high-pressure sound velocities of the single- and poly-crystals Ta are also calculated based on the elastic constants, and the predications exhibit good agreement with the existing experimental data. [ABSTRACT FROM AUTHOR]

A new method, which combines non-equilibrium plasma reaction with template-controlled growth technology, has been developed for synthesizing aligned carbon nanotubes at atmospheric pressure and low temperature. Multiwall carbon nanotubes with diameters of approximately 40 nm were restrictedly synthesized in the channels of anodic aluminum oxide template from a methane/hydrogen mixture gas by a.c. corona discharge plasma reaction at a temperature below 200 °C. It was observed that amorphous carbon deposited on the tops of the carbon nanotubes. The formation mechanism of carbon nanotubes synthesized by corona discharge plasma method was discussed. [Copyright &y& Elsevier]

Atherosclerotic plaques form in the inner layer of arteries triggering heart attacks and strokes. Although T cells have been detected in atherosclerosis, tolerance dysfunction as a disease driver remains unexplored. Here we examine tolerance checkpoints in atherosclerotic plaques, artery tertiary lymphoid organs and lymph nodes in mice burdened by advanced atherosclerosis, via single-cell RNA sequencing paired with T cell antigen receptor sequencing. Complex patterns of deteriorating peripheral T cell tolerance were observed being most pronounced in plaques followed by artery tertiary lymphoid organs, lymph nodes and blood. Affected checkpoints included clonal expansion of CD4 + , CD8 + and regulatory T cells; aberrant tolerance-regulating transcripts of clonally expanded T cells; T cell exhaustion; T reg -TH 17 T cell conversion; and dysfunctional antigen presentation. Moreover, single-cell RNA-sequencing profiles of human plaques revealed that the CD8 + T cell tolerance dysfunction observed in mouse plaques was shared in human coronary and carotid artery plaques. Thus, our data support the concept of atherosclerosis as a bona fide T cell autoimmune disease targeting the arterial wall., Competing Interests: Competing interests S.K.M., A.J.R.H. and C.Y. declare competing interests. C.Y., S.K.M. and A.J.R.H. are owners of Easemedcontrol R&D & Co KG, Munich, Germany; C.Z., A.J.R.H. and C.Y. are inventors on a pending patent application related to the diagnostics and therapeutic usages of TCRs/B cell receptors to treat atherosclerosis. The remaining authors declare no competing interests.

Humidity-induced multiple-step single-crystal to single-crystal (SC-SC) transformations are observed in the cobalt phosphonate (NH4)3[Co2(bamdpH)2(HCOO)(H2O)2] (1), where bamdpH4 is (benzylazanediyl)bis(methylene)diphosphonic acid, [C6H5CH2N(CH2PO3H2)2]. Under high-humidity conditions (95% RH), compound 1 experiences hydrolysis at 60 °C which is accompanied by the transformation from a double-chain structure of compound 1 into a single-chain structure of [Co(bamdpH2)(H2O)2]·2H2O (2). When the humidity is below 10% RH, part of the lattice water in compound 2 can be released, forming a third phase, [Co(bamdpH2)(H2O)2]·H2O (3). The structural transformation processes have been monitored by infrared and proton conductivity measurements.