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Multiply Charged Anions,Maximum Charge Acceptance,and Higher Electron Affinities of Molecules,Superatoms,and Clusters

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物理化学学报 2018年第6期34卷 675-682页

作者： VON SZENTPálY lászló Institut fur Theoretische Chemie Universitat Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany.

The addition of electrons to form gas-phase multiply charged anions(MCAs)normally requires sophisticated experiments or *** this work,the factors stabilizing the MCAs,the maximum electron uptake of gas-phase molecules,X,and the electronic stability of MCAs X^(Q-),are *** drawbacks encountered when applying computational and/or conceptual density functional theory(dFT)to MCAs are *** develop and test a different model based on the valence-state *** in dFT,the electronic energy,E(N,v_(ex)),is a continuous function of the average electron number,N,and the external potential,v_(ex),of the *** valence-state-parabola is a second-order polynomial that allows extending E(N,v_(ex))to dianions and higher *** model expresses the maximum electron acceptance,Q_(max),and the higher electron affinities,A_Q,as simple functions of the firstelectron affinity,A_1,and the ionization energy,I,of the"ancestor"***,the maximum electron acceptance is Q_(max,calc)=1+12A_1/7(I-A_1).The ground-state parabola model of the conceptual dFT yields approximately half of this value,and it is termed Q_(max,GS)=?+A_1/(I-A_1).A large variety of molecules are evaluated including fullerenes,metal clusters,super-pnictogens,super-halogens(OF_3),super-alkali species(Oli_3),and neutral or charged transition-metal complexes,AB_(m )l_n^(0/+/-).The calculated second electron affinity A_(2,calc)=A_1-(7/12)(I-A_1)is linearly correlated to the literature references A_(2,lit) with a correlation coefficient R=0.998.A_2 or A_3 values are predicted for further 24 *** appearance sizes,n_(ap)^(3-),of triply charged anionic clusters and fullerenes are calculated in agreement with the literature.

关键词： Multiply charged negative ions Their appearance sizes Second electron affinity Third electronaffinity Conceptual density-functional theory Valence-state parabola model of electronegativity

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多参数Z谱MRI对临床胶质瘤分层诊断可能有更好的作用

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国际医学放射学杂志 2022年第2期 239-240页

作者： C.l.Su S.J.Xu d.l.lin H.Q.He Z.H.Chen F.C.damen 朱能谨

摘要目的利用多重对比Z谱MRI对胶质瘤级别、异柠檬酸脱氢酶（IdH）基因型以及1p/19q共缺失状态进行全面、无创的风险因素分层。方法回顾性研究了113例胶质瘤

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Improved data gap-filling schemes for estimation of net ecosystem exchange in typical East-Asian croplands

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Science China Earth Sciences 2016年第8期59卷 1652-1664页

作者： ZHAO Peng Johannes lüERS department of Micrometeorology University of Bayreuth Institute of Ecology University of Innsbruck Member of Bayreuth Center of Ecology and Environmental Research (BayCEER) University of Bayreuth

The estimation of carbon exchange between ecosystems and the atmosphere suffers unavoidable data gaps in eddy-covariance technique, especially for short-living and fast-growing croplands. In this study we developed a modified gap-filling scheme introducing a leaf area index factor as the vegetation status information based on the conventional light response function for two East-Asian cropland sites (rice and potatoes). This scheme’s performance is comparable to the conventional time window scheme, but has the advantage when the gaps are large compared to the total length of the time series. To investigate how the time binning approach performs for fast-growing croplands, we tested different widths of the time window, showing that a four-day window for the potato field and an eight-day time window for the rice field perform the best. The insufficiency of the conventional temperature binning approach was explained as well as the influence of vapor pressure deficit. We found that vapor pressure deficit plays a minor role in both the potato and the rice fields under Asian monsoon weather conditions with the exception of the early pre-monsoon growing stage of the potatoes. Consequently, we recommend using the conventional time-window scheme together with our new leaf-light response function to fill data gaps of net ecosystem exchange in fast-growing croplands.

关键词： Eddy-covariance Gap-filling Net ecosystem exchange lAI

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Effects of human disturbance on nest placement of the woodpigeon (Columba palumbus): a case study from the Middle Atlas, Morocco

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Integrative Zoology 2014年第3期9卷 349-359页

作者： Saâd HANANE Forest Research Center High Commissariat for WaterForests and Desertification ControlRabat-AgdalMorocco

The woodpigeon(Columba palumbus)is a common and widespread bird in Morocco(North Africa).I examined,over 2 years(2010 and 2011),the breeding density and nest placement of this game species in relation to nest site habitat and degree of human *** study area was in the Middle Atlas Tighboula mountain forest,Morocco,in a disturbed and an undisturbed *** data collected in the 2 study sites,I aimed to identify the factors influencing the placement of nests within holm oak trees(Quercus rotundifolia)and their densities.I found that habitat structures,influenced by grazing disturbance,have affected nesting density and the location of nests of this *** place their nests in a higher position(3.42±0.19 m)when disturbance intensity is high and lower(1.68±0.1 m)when disturbance intensity is low,and show higher nesting density in less disturbed zone(3.1±0.4 nests/ha)than in highly disturbed zones(1.4±0.2 nests/ha).Grazing disturbance could pose a threat to population persistence at a broader scale and could potentially reduce the abundance of this species by altering the composition and the structure of the forest nesting *** multi-scale studies are needed to assess the effects of different levels of grazing disturbance on woodpigeon nest density and placement,and to enhance our knowledge of the breeding behavior of this game species under variable environments.

关键词： breeding density Columba palumbus holm oak Middle Atlas Morocco nest location woodpigeon

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ANAlYSIS ON THE BEHAVIOR OF PRECIPITATES IN UlTRA-THIN HOT STRIP OF PlAIN lOW CARBON STEEl PROdUCEd BY COMPACT STRIP PROdUCTION

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Acta Metallurgica Sinica(English letters) 2002年第4期15卷 375-379页

作者： H.Yu,Y.l.Kang,H.B.dong,d.l.liu and J.FuUniversity of Science and Technology Beijing, Beijing 100083, China Manuscript received 10 October 2001 in revised form 25 January 2002 Univ. of Sci. and Technol. Beijing Beijing 100083 China

This paper investigated the mechanism of precipitation and its influence upon prop-erties of ultra-thin hot strips of low carbon steel produced by CSP techniques using experiment and thermodynamics theory. The experimental results show that there are lots of fine and dispersive precipitates in microstructures. By analysis, most of aluminum nitrides are in grains, while coexisted precipitates of MnS are along grain boundaries. Coexisted precipitates compose cation-vacancy type oxides such as Al2O3 in the core, while MnS is at the fringe of surface. The precipitation behavior of AIN and MnS in the hot strip is studied by thermodynamic calculation. At last, implica-tions between strengthening effect and techniques are analyzed using obtained solubility products.

关键词： CSP precipitation thermodynamics strengthening

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A review of challenges and opportunities in micropillar compression studies in Mg alloys

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Journal of Magnesium and Alloys 2023年第11期11卷 4043-4053页

作者： A.Kodam M.S.Gundi Y.l.Chiu I.P.Jones S.S.Singh J.Jain department of Materials Science and Engineering Indian Institute of Technology DelhiNew Delhi 110016India School of Metallurgy and Materials University of BirminghamEdgbastonBirmingham B152TTUK department of Materials Science and Engineering Indian Institute of Technology KanpurUttar Pradesh 208016India

This review paper provides an overview of the micropillar compression technique as applied to magnesium(Mg) and its alloys. It explores the influence of various factors, such as pillar size, shape, temperature, and strain rate on the mechanical properties of ***, the impact of alloying elements, aging, and precipitates in Mg alloys has been extensively examined, revealing their significant influence on mechanical performance. The study highlights the strength and strain hardening improvements in Mg with decreasing pillar size in micropillar compression. Furthermore, the role of precipitates as strengthening agents, affecting deformation mechanisms and overall mechanical response, is explored. These valuable insights are crucial for designing Mg-based materials with enhanced mechanical properties for advanced engineering applications.

关键词： A review of challenges and opportunities in micropillar compression studies in Mg alloys

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Gravitational collapse with standard and dark energy in the teleparallel equivalent of general relativity

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Chinese Physics B 2012年第6期21卷 57-62页

作者： Gamal G.l.Nashed Mathematics department Faculty of ScienceKing Faisal UniversityP.O.Box 380 Al-Ahsaa 31982the Kingdom of Saudi Arabia Mathematics department Faculty of ScienceAin Shams UniversityCairo11566Egypt Center for Theoretical Physics British University of EgyptSherouk City 11837P.O.Box 43Egypt

A perfect fluid with self-similarity of the second kind is studied within the framework of the teleparallel equivalent of general relativity （TEGR）. A spacetime which is not asymptotically fiat is derived. The energy conditions of this spacetime are studied. It is shown that after some time the strong energy condition is not enough to satisfy showing a transition from standard matter to dark energy. The singularities of this solution are discussed.

关键词： perfect fluid with self-similarity of second kind teleparallel equivalent of general relativ-ity asymptotically nonflat spacetime energy conditions

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Retraced longitudinal stacks low-frequency mosaic cylinder transducer

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Chinese Journal of Acoustics 2022年第2期41卷 143-153页

作者： lü Kejia lI Junbao lI Yuan Institute of Acoustics Chinese Academy of SciencesBeijing 100190 Beijing Engineering Technology Research Center of Ocean Acoustic Equipment Beijing 100190

A small-size low-frequency horizontal omni-directional cylinder transducer is *** is composed of four cylinder-shaped head mass blocks and four retraced piezoelectric ceramic longitudinal stacks sharing with one back mass *** transducer is analyzed and designed by using finite element method(FEM).A prototype is manufactured and *** results show that the maximum diameter of the transducer is 180 mm,the resonance frequency is 1.5 kHz,the maximum transmitting voltage response level is 131 dB and the maximum source level is above 188 dB,and the directivity of the transducer is horizontal *** transducer has the advantages of low frequency,small size and horizontal omni-directional,and has some good application prospects.

关键词： cylinder directional ceramic

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Cultured meat in western media: The disproportionate coverage of vegetarian reactions, demographic realities, and implications for cultured meat marketing

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Journal of Integrative Agriculture 2015年第2期14卷 264-272页

作者： Patrick d Hopkins department of Philosophy Millsaps College Center for Bioethics University of Mississippi Medical CenterJackson MS 39210USA

This paper examines the media coverage of the 2013 london cultured meat tasting event, particularly in the United States, Canada, and the United Kingdom. Using major news outlets, prominent magazines covering food and science issues, and advocacy websites concerning meat consumption, the paper characterizes the overall emphases of the coverage, the tenor of the coverage, and compares the media portrayal of the important issues to the demographic and psychological realities of the actual consumer market into which cultured meat will compete. In particular, the paper argues that Western media gives a distorted picture of what obstacles are in the path of cultured meat acceptance, especially by overemphasizing and overrepresenting the importance of the reception of cultured meat among vegetarians. Promoters of cultured meat should recognize the skewed impression that this media coverage provides and pay attention to the demographic data that suggests strict vegetarians are a demographically negligible group. Resources for promoting cultured meat should focus on the empirical demographics of the consumer market and the empirical psychology of mainstream consumers.

关键词： cultured meat vegetarianism vegans Mark Post in vitro meat moral psychology consumer market disgust

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Nitric oxide(NO) decomposition on catalysts, containing oxides of lanthanum and cerium, supported on γ-alumina

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Journal of Rare Earths 2019年第2期37卷 151-159页

作者： d.Stoyanova P.Georgieva I.Avramova K.Aleksieva d.Marinova d.Mehandjiev Institute of General and Inorganic Chemistry-BAS Institute of Catalysis-BAS

The present work was devoted to study the catalytic activity of lanthanum and cerium oxides separately,deposited on g-alumina in the reaction of decomposition of nitric oxide. The catalyst samples were prepared by the method of impregnation of g-Al_2 O_3 using solutions, containing nitrates of lanthanum and cerium. The prepared samples were calcined for 4 h at temperature 650℃ in an oven in air atmosphere. The catalysts were characterized by: chemical analysis by inductively coupled plasma atomic emission spectrometry(ICP-AES), X-ray diffraction(XRd), X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM) combined with energy-dispersive X-ray spectroscopy(EdS), electron paramagnetic resonance(EPR) and infrared(IR) spectroscopy, as well as measurement of the specific surface area. The results show that the catalysts based on lanthanum oxide and cerium oxide deposited on alumina display high catalytic activity over 60% conversion degree with respect to decomposition of nitric oxide in the absence of reducing agent. In the presence of reducer the activity reaches 90% conversion degree.

关键词： Rare earths Catalysts Catalytic activity decomposition of nitric oxide

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