51 research outputs found

    Using a Knowledge Graph to Discover Earth Science Information

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    Knowledge graphs link key entities within a specific domain to other entities via relationships. Researchers are able to mine these relationships from numerous sources to infer new knowledge. Text extraction from peer-reviewed papers and scientific reports are untapped resources that can be leveraged by knowledge graphs to accelerate scientific discovery

    The Paramagnetic or Spin Crossover Iron(III) Complexes Based-on Pentadentate Schiff Base Ligand: Crystal Structure, and Magnetic Property Investigation

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    A series of bi- or mononuclear hexacoordinate iron(III) complexes, [Fe(L)][Fe(bpb)(CN)2]·CH3OH·0.5H2O (1), [Fe(L)][Co(bpb)(CN)2]·CH3OH (2) [(Fe (L))2(4,4’-bipy)](BPh4)2 (3), [Fe(L)(py)](BPh4) (4) and [Fe(L)(dmap)](BPh4) (5) (bpb = 1,2-bis(pyridine-2-carboxamido)benzenate, L = N,N’-bis(2-hydroxybenzyliden)-1,7-diamino-4-azaheptane, dmap = 4-dimethylaminopyridine), have been prepared with the pentadentate Schiff base iron(III) compound as assemble precursor and characterized by element analysis, IR and X-ray diffraction. Single crystal structural determination revealed the neutral cyanide-bridged binuclear entity for complexes 1 and 2 and the cationic di- or mononuclear structure for complexes 3–5 with the positive charge(s) balanced by BPh4– ion(s). The experimental study and theoretical simulation of the magnetic property discovered the ferromagnetic coupling between the Fe(III) ions bridged by cyanide group in complex 1 and the always high spin state of the Fe(III) ion coordinated to the Schiff base ligand in both complexes 1 and 2. The temperature dependent magnetic susceptibility investigation over complexes 3–5 showed the occurrence of the thermo-induced gradual complete spin crossover (SCO) property at about 115, 170 and 200 K, respectively

    Liquid-crystalline circularly polarised fluorescent emitters with a high luminescence dissymmetry factor

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    Chiral liquid-crystalline emitters based on 9,9-dimethyl-10-(4-(phenylsulfonyl)phenyl)-9,10-dihydroacridine and a functionalised binaphthol show smectic liquid crystal phases and circularly polarised blue fluorescence with a high luminescence dissymmetry factor |glum| of 0.13. Solution-processable organic light-emitting diodes (OLEDs) based on the enantiomers were explored

    Spin Crossover in a Series of Non-Hofmann-Type Fe(II) Coordination Polymers Based on [Hg(SeCN)3]-; or [Hg(SeCN)4]2-; Building Blocks

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    This document is the Accepted Manuscript version of a Published Work that appeared in final form in Inorganic Chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acs.inorgchem.1c00802.[EN] Self-assembly of [Hg(SeCN)(4)](2)-tetrahedral building blocks, iron(II) ions, and a series of bis-monodentate pyridyltype bridging ligands has afforded the new heterobimetallic Hg-II-Fe-II coordination polymers {Fe[Hg(SeCN)(3)](2)(4,4'-bipy)(2)}(n) (1), {Fe[Hg(SeCN)(4)](tvp)}(n) (2), {Fe[Hg(SeCN)(3)](2)(4,4'-azpy)(2)}(n) (3), {Fe[Hg(SeCN)(4)](4,4'-azpy)(MeOH)} n (4), {Fe[Hg(SeCN)(4)](3,3'- bipy)} n (5) and {Fe[Hg(SeCN)4](3,3'-azpy)}(n) (6) (4,4-bipy = 4,4'-bipyridine, tvp = trans-1,2-bis(4-pyridyl)ethylene, 4,4'-azpy = 4,4'-azobispyridine, 3,3-bipy = 3,3'bipyridine, 3,3'-azpy = 3,3'-azobispyridine). Single-crystal X-ray analyses show that compounds 1 and 3 display a two-dimensional robust sheet structure made up of infinite linear [(FeL)n]2n+ (L = 4,4'-bipy or 4,4'-azpy) chains linked by in situ formed {[Hg(L)(SeCN)(3)](2)}(2)-anionic dimeric bridges. Complexes 2 and 4-6 define three-dimensional networks with different topological structures, indicating, in combination with complexes 1 and 3, that the polarity, length, rigidity, and conformation of the bridging organic ligand play important roles in the structural nature of the products reported here. The magnetic properties of complexes 1 and 2 show the occurrence of temperature-and light-induced spin crossover (SCO) properties, while complexes 4-6 are in the high-spin state at all temperatures. The current results provide a new route for the design and synthesis of new SCO functional materials with non-Hofmann-type traditional structures.This work was supported by the Natural Science Foundation of China (21671121and 21773006), the Spanish Ministerio de Ciencia e Innovacion (MICINN) and FEDER funds (PID2019-106147GB-I00), and Unidad de Excelencia Maria de Maeztu (CEX2019-000919-M).Cao, T.; Valverde-Muñoz, FJ.; Duan, X.; Zhang, M.; Wang, P.; Xing, L.; Sun, F.... (2021). Spin Crossover in a Series of Non-Hofmann-Type Fe(II) Coordination Polymers Based on [Hg(SeCN)3]-; or [Hg(SeCN)4]2-; Building Blocks. Inorganic Chemistry. 60(15):11048-11057. https://doi.org/10.1021/acs.inorgchem.1c008021104811057601

    2020 roadmap on two-dimensional materials for energy storage and conversion

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    Energy storage and conversion have attained significant interest owing to its important applications that reduce CO2 emission through employing green energy. Some promising technologies are included metal-air batteries, metal-sulfur batteries, metal-ion batteries, electrochemical capacitors, etc. Here, metal elements are involved with lithium, sodium, and magnesium. For these devices, electrode materials are of importance to obtain high performance. Two-dimensional (2D) materials are a large kind of layered structured materials with promising future as energy storage materials, which include graphene, black phosporus, MXenes, covalent organic frameworks (COFs), 2D oxides, 2D chalcogenides, and others. Great progress has been achieved to go ahead for 2D materials in energy storage and conversion. More researchers will join in this research field. Under the background, it has motivated us to contribute with a roadmap on ‘two-dimensional materials for energy storage and conversion

    Typological Features and Determinants of Men’s Marriage Expenses in Rural China: Evidence from a Village-Level Survey

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    Poverty due to the high marriage expenses in rural China has drawn considerable attention. In this paper, based on the data of the “Hundreds of Villages Survey in China” conducted in 2018, we analyze the characteristics, trends, and typological features of rural men’s marriage expenses, and identify the determinants of rural men’s marriage expenses types under the guidance of marriage exchange theory. With the help of latent profile analysis, multinomial logit analysis, and OLS analysis, this study firstly identifies four types of marriage expenses for Chinese rural men including the “bride price & marital house”, the “mixed”, the “bride price biased”, and the “marital house biased”, and secondly finds significant associations of educational level matching, occupational level matching, and type of urbanization with different types of rural men’s marriage expenses. If a rural man has a higher education than his wife, his marriage costs are less likely to be “bride price biased”, and when his occupational level is higher, his marriage cost is more likely to be “marital house biased”, which means greater financial pressure on him. Our research verifies the theory of marriage exchange into the quantitative analysis of marriage expenses for the first time, which effectively explains the reasons for the rising cost of marriage and provides an empirical basis for effectively managing this social problem

    Research on High-Speed Railway Pricing and Financial Sustainability

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    With the steady increase of corporate system reform in the railway transportation industry, high-speed railways have accelerated their steps toward marketization, and the market competition they face has become increasingly fierce. In this context, enterprises need to make quick adjustments to new changes in order to seize the market share, obtain stable ticket income, and eventually, achieve financial sustainability while ensuring the healthy development of high-speed railways. Thus, it is particularly important to determine a reasonable ticket price. While considering supply and demand, market competition, and passenger utility, this study constructs a model of the passenger flow sharing rate and applies it to modeling the optimal ticket price for high-speed railways, taking the Beijing–Shanghai High-speed Railway as an example for calculating this model. Using the results calculated, this study analyzes the influence of the optimal ticket price on the financial sustainability of the enterprise through use of the evaluation system of financial sustainability established above. The results show that the existing price for a train ticket from of Beijing to Shanghai is not the optimal one, and there is still room for a price increase; the ticket price has an impact on financial sustainability by affecting corporate operating income and cash flow. The study provides a method for formulating the optimal ticket price for high-speed railway travel and enriches the research on the financial sustainability of high-speed railways

    The Relationship between Mindfulness and Social Adaptation among Migrant Children in China: The Sequential Mediating Effect of Self-Esteem and Resilience

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    Social adaptation of migrant children is not only related to the physical and mental health and development of individuals, but also reflects the level of urban social integration and stable development. Mindfulness has a protective effect on individual social adaptation. Self-esteem and resilience were found to be positively associated with mindfulness and social adaptation. Based on the Positive Youth Development Perspective, this study aimed to explore whether self-esteem and resilience sequentially mediated the associations among mindfulness and social adaptation. A total of 526 migrant children were assessed with the questionnaires regarding mindfulness, self-esteem, resilience, and social adaptation. The results indicated that mindfulness was positively associated with social adaptation of migrant children. Self-esteem and resilience played the sequential mediating roles between mindfulness and social adaptation. The present study revealed the influence and mechanism of mindfulness on social adaptation and provided some guidance for the intervention programs to promote migrant children’s adaptability
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