383 research outputs found

    Members of the PbFCI-Type Family: Possible Candidates for Room-Temperature Photochemical Hole Burning

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    We report on crystal growth and about physico-chemical studies on SryBa1-yFClxBr1-x (y = 0, 0.5, and 1) compounds doped with Sm. Persistent spectral hole burning at 300 K is further reported on Sr0.5Ba0.5FCl0.5Br0.5:Sm single crystals

    Danger control programs cause tissue injury and remodeling.

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    Are there common pathways underlying the broad spectrum of tissue pathologies that develop upon injuries and from subsequent tissue remodeling? Here, we explain the pathophysiological impact of a set of evolutionary conserved danger control programs for tissue pathology. These programs date back to the survival benefits of the first multicellular organisms upon traumatic injuries by launching a series of danger control responses, i.e., 1. Haemostasis, or clotting to control bleeding; 2. Host defense, to control pathogen entry and spreading; 3. Re-epithelialisation, to recover barrier functions; and 4. Mesenchymal, to repair to regain tissue stability. Taking kidney pathology as an example, we discuss how clotting, inflammation, epithelial healing, and fibrosis/sclerosis determine the spectrum of kidney pathology, especially when they are insufficiently activated or present in an overshooting and deregulated manner. Understanding the evolutionary benefits of these response programs may refine the search for novel therapeutic targets to limit organ dysfunction in acute injuries and in progressive chronic tissue remodeling

    Danger control programs cause tissue injury and remodeling.

    Get PDF
    Are there common pathways underlying the broad spectrum of tissue pathologies that develop upon injuries and from subsequent tissue remodeling? Here, we explain the pathophysiological impact of a set of evolutionary conserved danger control programs for tissue pathology. These programs date back to the survival benefits of the first multicellular organisms upon traumatic injuries by launching a series of danger control responses, i.e., 1. Haemostasis, or clotting to control bleeding; 2. Host defense, to control pathogen entry and spreading; 3. Re-epithelialisation, to recover barrier functions; and 4. Mesenchymal, to repair to regain tissue stability. Taking kidney pathology as an example, we discuss how clotting, inflammation, epithelial healing, and fibrosis/sclerosis determine the spectrum of kidney pathology, especially when they are insufficiently activated or present in an overshooting and deregulated manner. Understanding the evolutionary benefits of these response programs may refine the search for novel therapeutic targets to limit organ dysfunction in acute injuries and in progressive chronic tissue remodeling

    Хранение, накопление и утилизация нефтешламов

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    Synthesis of a Bimetallic Dodecaborate LiNaB_(12)H_(12)with Outstanding Superionic Conductivity

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    Metal dodecaborates M_2/_nB_(12)H_(12) (n denotes the valence of the metal M), containing icosahedral polyatomic anion [B_(12)H_(12)]^(2−), have been attracting increasing interest as potential energy materials, especially in the context of hydrogen storage and superionic conductivity. M_2/_nB_(12)H_(12) are commonly formed as dehydrogenation intermediates from metal borohydrides M(BH_4)_n, like LiBH_4 and Mg(BH_4)_2, which are well-known as potential high-density hydrogen storage materials. The strong B−B bond in the icosahedral [B_(12)H_(12)]^(2−), however, is regarded to be the key factor that prevents the rehydrogenation of dodecaborates. In order to elucidate the mechanism as well as to provide effective solutions to this problem, a novel solvent-free synthesis route of anhydrous M_2/nB_(12)H_(12) (here M means Li, Na, and K) has been developed. Thermal stability and transformations of the anhydrous single phase Li_2B_(12)H_(12) suggested the formation of the high temperature polymorph of Li_2B_(12)H_(12) during the dehydrogenation of LiBH_4, while concurrently emphasized the importance of further investigation on the decomposition mechanism of metal borohydrides and metal dodecaborates. The high stability of icosahedral [B_(12)H_(12)]^(2−), on the other hand, favors its potential application as solid electrolyte. Recently, Na^+ conductivity of Na_2B_(12)H_(12) was reported to be 0.1 S/cm above its order−disorder phase transition at ∼529 K, which is comparable to that of a polycrystalline β”-Al_2O_3 (0.24 S/cm at 573 K) solid state Na-electrolyte. Mechanistic understanding on the diffusion behavior of cation and further improvement of ionic conductivity at a lower temperature, however, are important in order to facilitate the practical application of metal dodecaborates as superionic conductors

    Structural and dynamic studies of Pr(11^{11}BH4_{4})3_{3}

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    Rare earth borohydrides RE (BH4)(3) are studied in the context of energy storage, lumines-cence and magnetic applications. We have investigated the structural behavior of pra-seodymium borohydride Pr ((BH4)-B-11)(3) containing B-11 isotope because of the previously reported negative thermal expansion. Differential scanning calorimetry (DSC), in-situ var-iable temperature synchrotron radiation powder X-ray diffraction (SR-PXD) and infrared studies reveal that Pr ((BH4)-B-11)(3) undergoes to a volume contraction during the phase tran-sition from alpha alpha-Pr ((BH4)-B-11)(3) to rhombohedral r-Pr ((BH4)-B-11)(3) phase upon heating to 493 K. Surprisingly, the phase transition persists upon cooling at room temperature. Vibrational analysis also shows that the stretching frequency of BH4-3; anion does not change upon heating which indicates that the B-H bond length remains constant during the structural phase transition from alpha-Pr ((BH4)-B-11)(3) to r-Pr ((BH4)-B-11)(3) phase. Additionally, the energy barrier of reorientation motion of the BH4- anion in the alpha-phase was estimated to be ca 23 kJ/mol by quasi-elastic neutron scattering (QENS) and Raman spectroscopy. (C) 2021 The Authors. Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC
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