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Globally, the accelerating use of renewable energy sources, enabled by increased efficiencies and reduced costs, and driven by the need to mitigate the effects of climate change, has significantly increased research in the areas o...
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Globally, the accelerating use of renewable energy sources, enabled by increased efficiencies and reduced costs, and driven by the need to mitigate the effects of climate change, has significantly increased research in the areas of renewable energy production, storage, distribution and end-use. Central to this discussion is the use of hydrogen, as a clean, efficient energy vector for energy storage. This review, by experts of Task 32, "Hydrogen-based Energy Storage" of the International Energy Agency, Hydrogen TCP, reports on the development over the last 6 years of hydrogen storage materials, methods and techniques, including electrochemical and thermal storage systems. An overview is given on the background to the various methods, the current state of development and the future prospects. The following areas are covered; porous materials, liquid hydrogen carriers, complex hydrides, intermetallic hydrides, electrochemical storage of energy, thermal energy storage, hydrogen energy systems and an outlook is presented for future prospects and research on hydrogen-based energy storage. (C) 2020 The Authors. Published by Elsevier B.V.
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Efficient storage and conversion of renewable energies is of critical importance to the sustainable growth of human society. With its distinguishing features of high hydrogen content, high energy density, facile storage/transporta...
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Efficient storage and conversion of renewable energies is of critical importance to the sustainable growth of human society. With its distinguishing features of high hydrogen content, high energy density, facile storage/transportation, and zero-carbon emission, ammonia has been recently considered as a promising energy carrier for long-term and large-scale energy storage. Under this scenario, the synthesis, storage, and utilization of ammonia are key components for the implementation of ammonia-mediated energy system. Being different from fossil fuels, renewable energies normally have intermittent and variable nature, and thus pose demands on the improvement of existing technologies and simultaneously the development of alternative methods and materials for ammonia synthesis and storage. The energy release from ammonia in an efficient manner, on the other hand, is vital to achieve a sustainable energy supply and complete the nitrogen circle. Herein, recent advances in the thermal-, electro-, plasma-, and photocatalytic ammonia synthesis, ammonia storage or separation, ammonia thermal/electrochemical decomposition and conversion are summarized with the emphasis on the latest developments of new methods and materials (catalysts, electrodes, and sorbents) for these processes. The challenges and potential solutions are discussed.
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In this paper, the exponential stability of delayed neural networks (DNNs) with delayed sampleddata inputs is investigated via extended bilateral looped functional approach. Firstly, a new extended bilateral looped functional is c...
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In this paper, the exponential stability of delayed neural networks (DNNs) with delayed sampleddata inputs is investigated via extended bilateral looped functional approach. Firstly, a new extended bilateral looped functional is constructed, which is differentiable at sampling intervals and can relax the constraints on positive definiteness when compared to traditional functionals. Then, less conservative criteria for exponential stability of DNNs with delayed sampled-data inputs expressed through linear matrix inequalities (LMIs) are obtained. Furthermore, the results are extended to T-S fuzzy DNNs with delayed sampled-data inputs, where corresponding stability conditions are likewise derived. Finally, two simulation examples are given to illustrate the validity of the main results.& COPY; 2023 The Franklin Institute. Published by Elsevier Inc. All rights reserved.
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Liquid hydrogen carriers are considered to be attractive hydrogen storage options because of their ease of integration into existing chemical transportation infrastructures when compared with liquid or compressed hydrogen. The dev...
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Liquid hydrogen carriers are considered to be attractive hydrogen storage options because of their ease of integration into existing chemical transportation infrastructures when compared with liquid or compressed hydrogen. The development of such carriers forms part of the work of the International Energy Agency Task 32: Hydrogen-Based Energy Storage. Here, we report the state-of-the-art for ammonia-based and liquid organic hydrogen carriers, with a particular focus on the challenge of ensuring easily regenerable, high-density hydrogen storage. (C) 2019 The Authors. Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC.
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A family of monomers, including 2,5-hexandiol, 2,7-octandiol, 2,5-furandicarboxylic acid (FDCA), terephthalic acid (TA), and branched-chain adipic and pimelic acid derivatives, all find a common derivation in the biomass-derived p...
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A family of monomers, including 2,5-hexandiol, 2,7-octandiol, 2,5-furandicarboxylic acid (FDCA), terephthalic acid (TA), and branched-chain adipic and pimelic acid derivatives, all find a common derivation in the biomass-derived platform molecule 5-(chloromethyl) furfural (CMF). The diol monomers, previously little known to polymer chemistry, have been combined with FDCA and TA derivatives to produce a range of novel polyesters. It is shown that the use of secondary diols leads to polymers with higher glass transition temperatures (T-g) than those prepared from their primary diol equivalents. Two methods of polymerisation were investigated, the first employing activation of the aromatic diacids via the corresponding diacid chlorides and the second using a transesterification procedure. Longer chain diols were found to be more reactive than the shorter chain alternatives, generally giving rise to higher molecular weight polymers, an effect shown to be most pronounced when using the transesterification route. Finally, novel diesters with high degrees of branching in their hydrocarbon chains are introduced as potential monomers for possible low surface energy materials applications.
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Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease associated with persistent multiarticular synovitis, cartilage destruction, and even loss of joint function. Although remarkable progress has been made in the ...
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Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease associated with persistent multiarticular synovitis, cartilage destruction, and even loss of joint function. Although remarkable progress has been made in the clinical treatment of RA, long-term administration of anti-rheumatic drugs still suffers quite a few drawbacks, including high dose and high frequency of drug use, as well as dysfunction of the heart, liver, kidney, and so forth. For the above problems, nanotherapeutic agents are developed to avert non-specific binding and upregulate the efficacy by improving the accumulation of drugs in lesion tissues. In this article, some of the most frequently used anti-RA agents were summarized, and the recent treatment of RA with passive or active targeting nanotheranostics was systematically illustrated. In addition, the prospect of nanovehicles in clinical therapy of RA was discussed and predicted. (C) 2017 Elsevier B. V. All rights reserved.
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We have synthesized a series of metal-organic coordination frameworks under solvothermal conditions, formulated as [Cu(L)(phen)](1), [Co-2(L)(2)(bib)]CH3OH(2), [Co(L)(btmb)(0.5)](3), [Zn(L)(bib)]2H(2)O(4), [Cu(L)(bib)]DMF(5), and ...
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We have synthesized a series of metal-organic coordination frameworks under solvothermal conditions, formulated as [Cu(L)(phen)](1), [Co-2(L)(2)(bib)]CH3OH(2), [Co(L)(btmb)(0.5)](3), [Zn(L)(bib)]2H(2)O(4), [Cu(L)(bib)]DMF(5), and [Mn-4(L)(4)(bimb)(CH3OH)](6) based on a flexible multicarboxylic bridging ligand 4,4-methylenebis(oxy)-dibenzoic acid (H2L) and flexible N-donor ligands 1,4-bis (1H-imidazol-1-yl)-butane (bib), 1,4-bis(1H-1,2,4-triazol- 1-ylmethyl)benzene (btmb), and 1,4-bis(1H-imidazol-1-ylmethyl)benzene (bimb). The structures of the frameworks have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, and thermogravimetric analyses. The crystal structure determinations reveal that 1 has a 1-D Z-shape chain. Compounds 2 and 3 are 2-D twofold parallel interpenetrating 4-connected net with the Schlafli symbol {4(4)6(2)}. Compound 4 is a 2-D threefold parallel interpenetrating 4-connected nets with the Schlafli symbol {4(4)6(2)}. Compound 5 is 3-D 4-connected net with the Schlafli symbol {6(5)8}. Compound 6 is characterized by a three-dimensional framework with one-dimensional homogeneous Mn-carboxylate chain. We found that flexible carboxylate ligands have different coordination modes under different synthetic conditions. The flexible skeleton of ligands and the coordination angle between the ligand and the metal ion is described. The luminescence and thermogravimetric properties of these compounds have been investigated.
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Heterogeneous catalysis using sole metal-organic frameworks (MOFs) remains an immature field because these MOFs have insufficient active sites. The "inorganic effect" allows MOFs to become solid supports to immobilize polyoxometal...
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Heterogeneous catalysis using sole metal-organic frameworks (MOFs) remains an immature field because these MOFs have insufficient active sites. The "inorganic effect" allows MOFs to become solid supports to immobilize polyoxometalates and metal nanoparticles, whereas the "organic effect" enables MOFs to function with organic groups such as -NH2 and -SO3H. These functionalized MOFs can be applied in various reactions, such as oxidation, hydrogenation, Knoevenagel condensation, dehydration, and hydrolysis. This review presents the catalytic transformation of organic molecules and biomass derivatives with MOFs.
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The ocean plays an essential role in regulating global and regional climate, which is mainly achieved through sea surface temperature anomaly (SSTA) changes. Studies on global sea surface temperature (GSST) are primarily carried o...
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The ocean plays an essential role in regulating global and regional climate, which is mainly achieved through sea surface temperature anomaly (SSTA) changes. Studies on global sea surface temperature (GSST) are primarily carried out under linear assumption, which is not capable of fully revealing the evolution characteristics of sea surface temperature (SST) due to the non-linear and non-stationary nature of the SST. Here, the evolution of the GSST trend in the past century is investigated by using an adaptive and local spatial-temporally multidimensional ensemble empirical mode decomposition method. The results show that the global ocean has been warming except for the subpolar North Atlantic, the equatorial central Pacific, and the Southern Ocean in the Pacific sector. The equatorial central Pacific turned from cooling to warming around the middle of the last century made it one of the fastest-warming regions in recent decades with other regions located in the Arctic Ocean and the western-boundary current regions and their mid-latitude extensions in both hemispheres. The strongest warming during recent decades is found in the Arctic Ocean, east of the continents in the northern hemisphere, the entire Indian Ocean, and especially in the tropical Pacific Ocean. From a zonal average perspective, warming (>0.1 K since 1900) first took place in the subtropical regions of the Northern Hemisphere and 50 degrees S of the Southern Hemisphere almost simultaneously around 1910, then followed by the subpolar warming in the Northern Hemisphere. The first two bands of warming both expanded equatorward leading to the fast warming of tropical oceans, especially for the Pacific Ocean.
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With the development of three-dimensional (3D) printing technology, porous metal scaffolds can be well fabricated. In contrast to conventional methods, 3D printing of porous scaffolds is characterized by a controllable and precise...
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With the development of three-dimensional (3D) printing technology, porous metal scaffolds can be well fabricated. In contrast to conventional methods, 3D printing of porous scaffolds is characterized by a controllable and precise manufacturing process, which makes it possible to form customized predesigned implants for individual patients and achieve regular pore distribution at the micro scale. As the microenvironment of bone ingrowth, pores must provide sufficient space for cell attachment and proliferation. The behaviors of cells and bone ingrowth can influence the effect of 3D printed porous metal scaffolds on bone ingrowth. This review introduces 3D printing techniques shortly and focuses on the factors that potentially influence bone ingrowth into 3D printed porous metal scaffolds, e.g., materials, pore size, porosity, pore structure, surface modification, and mechanical properties. In each chapter, the mechanisms underlying cell-scaffold interactions are discussed in detail. In addition, the clinical applications of 3D printing are also introduced shortly. Finally, we list the most appropriate parameters for an excellent porous metal scaffold and attempt to identify a combination of these parameters that predicts good bone ingrowth. (C) 2017 Elsevier B.V. All rights reserved.
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