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Enhancement of the CO_(2)adsorption and hydrogenation to CH_(4)capacity of Ru–Na–Ca/γ–Al_(2)O_(3)dual function material by controlling the Ru calcination atmosphere

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Journal of Environmental Sciences 2024年第6期140卷 292-305页

作者： Alejandro Bermejo-López Beñat Pereda-Ayo jon a.onrubia-calvo JoséA.González-Marcos Juan R.González-Velasco Department of Chemical Engineering Faculty of Science and TechnologyUniversidad del País Vasco UPV/EHUBarrio Sarrienas/n48940 LeioaBizkaiaSpain

Integrated CO_(2)capture and utilization(ICCU)technology requires dual functional materials(DFMs)to carry out the process in a single reaction *** influence of the calcination atmosphere on efficiency of 4%Ru-8%Na_(2)CO_(3)-8%CaO/γ-Al_(2)O_(3)DFM is *** adsorbent precursors are first co-impregnated onto alumina and calcined in ***,Ru precursor is impregnated and four aliquotes are subjected to different calcination protocols:static air in muffle or under different mixtures(10%H_(2)/N_(2),50%H_(2)/N_(2)and N_(2))*** are characterized by XRD,N_(2)adsorption-desorption,H_(2)chemisorption,TEM,XPS,H_(2)-TPD,H_(2)-TPR,CO_(2)-TPD and *** catalytic behavior is evaluated,in cycles of CO_(2)adsorption and hydrogenation to CH_(4),and temporal evolution of reactants and products concentrations is *** calcination atmosphere influences the physicochemical properties and,ultimately,activity of *** data and catalytic performance discover the acccomodation of Ru nanoparticles disposition and basic sites is mostly influencing the catalytic *** calcined under N_(2)flow(RuNaCa-N_(2))shows the highest CH_(4)production(449μmol/g at 370℃),because a well-controlled decomposition of precursors which favors the better accomodation of adsorbent and Ru phases,maximizing the specific surface area,the Ru-basic sites interface and the participation of different basic sites in the CO_(2)methanation ***,the calcination in a N_(2)flow is revealed as the optimal calcination protocol to achieve highly efficient DFM for integrated CO_(2)adsorption and hydrogenation applications.

关键词： CO_(2)methanation Integrated CO_(2)capture and utilization(ICCU) Dual functional material(DFM) Ru calcination atmosphere

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On the rate of convergence of the maximum likelihood estimator of a k-monotone density

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Science China Mathematics 2009年第7期52卷 1525-1538页

作者： WELLNER jon A Department of Statistics University of Washington

Bounds for the bracketing entropy of the classes of bounded k-monotone functions on [0,A] are obtained under both the Hellinger distance and the Lp(Q) distance,where 1 p < ∞ and Q is a probability measure on [0,A].The result is then applied to obtain the rate of convergence of the maximum likelihood estimator of a k-monotone density.

关键词： bracketing metric entropy maximum likelihood estimator Hellinger distance 62G05 46B50

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Varieties for Cohomology with Twisted Coefficients

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Acta Mathematica Sinica,English Series 1999年第1期15卷 81-92页

作者： jon F.Carlson Department of Mathemtics University of GeorgiaAthensGA 30602 USA

Let G be a finite group and k a field of characteristic p>*** this paper we consider the support variety for the cohomology module ExtkG*（M,N） where M and N are *** is the subvariety of the maximal ideal spectrum of H*（G,k） of the annihilator of the cohomology module. For modules in the principal block we show that that the variety is contained in the intersections of the varieties of M and N and the difference between the that intersection and the support variety of the cohomology module is contained in the group theoretic *** other blocks a new nucleus is defined and a similar theorem is *** in the case of modules in a nonprincipal block several new difficulties are highlighted by some examples.

关键词： Group Cohomology Support varieties Cohomological varieties Annihilators of cohomology

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Phenotypic plasticity of labile traits in the wild

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Current Zoology 2013年第4期59卷 485-505页

作者： jon E. BROMMER Department of Biology University Hill 20014 University of Turku Finland ARONIA Research and Development Institute Novia Applied University and Abo Akademi University Raseborgsvaigen 9 10600 Ekenas Finland

Individual-based studies allow quantification ofphenotypic plasticity in behavioural, life-history and other labile traits The study of phenotypic plasticity in the wild can shed new light on the ultimate objectives （1） whether plasticity itself can evolve or is constrained by its genetic architecture, and （2） whether plasticity is associated to other traits, including fitness （selection）. I describe the main statistical approach for how repeated records of individuals and a description of the environment （E） allow quantification of variation in plasticity across individuals （IxE） and genotypes （GxE） in wild populations. Based on a literature review of life-history and behavioural studies on plasticity in the wild, I discuss the present state of the two objectives listed above. Few studies have quantified GxE of labile traits in wild populations, and it is likely that power to detect statistically sig- nificant GxE is lacking. Apart from the issue of whether it is heritable, plasticity tends to correlate with average trait expression （not fully supported by the few genetic estimates available） and may thus be evolutionary constrained in this way. Individ- ual-specific estimates of plasticity tend to be related to other traits of the individual （including fitness）, but these analyses may be anti-conservative because they predominantly concern stats-on-stats. Despite the increased interest in plasticity in wild popula- tions, the putative lack of power to detect GxE in such populations hinders achieving general insights. I discuss possible steps to invigorate the field by moving away from simply testing for presence of GxE to analyses that ＇scale up＇ to population level proce-sses and by the development of new behavioural theory to identify quantitative genetic parameters which can be estimated

关键词： Individual-level plasticity Life history Animal personality Linear mixed model Animal model Wild population Longitudinal study

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Some paradoxical observations about spheroidal graphite degeneracy

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China Foundry 2018年第6期15卷 457-463页

作者： Jacques Lacaze jon Sertucha CIRIMAT Université de ToulouseBP 44362F-31030ToulouseFrance Investigaeiòn y Desarrollo de Procesos Metalúrgicos IK4-AzterlanAliendalde auzunea 6E-48200Durango(Bizkaia)Spain

Differential thermal analysis experiments have been performed on samples machined from Y2-blocks cast with different high-silicon spheroidal graphite irons. Depending on magnesium, silicon, cerium and antimony content, the as-cast microstructure showed various levels of chunky graphite in the central part of the blocks. In contrast, the microstructure of the materials after remelting and resolidification during differential thermal analysis consisted of lamellar or compacted graphite. The formation of chunky graphite in the as-cast microstructure is rationalized using an index or silicon equivalent that has been recently suggested. The differences in the microstructures after differential thermal analysis are discussed in terms of available free magnesium. Emphasis is finally put on the striking differences in characteristic size of the microstructures made of compacted graphite as compared to lamellar graphite and chunky graphite. This leads to tentative conclusions about growth of compacted and chunky graphite which would be worthy of further experimental investigations.

关键词： high-silicon spheroidal graphite iron graphite degeneracy compacted graphite chunky graphite

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No trade-off between trichome production and tolerance to leaf and inflorescence damage in a natural population of Arabidopsis lyrata

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Journal of Plant Ecology 2014年第4期7卷 373-383页

作者： Adriana Puentes jonÅgren Department of Plant Ecology and Evolution Evolutionary Biology Centre(EBC)Uppsala UniversityNorbyvägen 18DSE-75236 UppsalaSweden

Aims Early models of plant defense conceived resistance and tolerance to herbivore damage as mutually exclusive *** for this idea has been equivocal and studies on these two strategies are still needed to understand the evolution of defenses in natural *** Arabidopsis lyrata,the production of trichomes,a documented resistance trait,has been associated with a fitness cost in the absence of *** examined whether trichome production is also associated with reduced tolerance to simulated herbivore *** We conducted a field experiment in a natural swedish population of *** where we inflicted leaf(0 vs.50%of the area of each leaf removed)and inflorescence damage(0 vs.50%of inflores-cences removed)to trichome-producing and glabrous plants in a factorial *** examined the response(survival,growth and reproduction)of the plants to the imposed damage over 2 *** Findingstrichome-producing plants were not less tolerant than glabrous plants to simulated herbivore damage(no significant morph×leaf damage or morph×inflorescence damage interactions).Inflorescence and leaf damage had independent negative effects on the performance of damaged *** damage reduced rosette size the year of damage,but effects on reproductive output in the year of damage,and on survival and reproductive performance the following year were weak and not statistically *** damage significantly reduced the number of flowers,fruits and seeds the year of damage,but not in the following *** of morph,the study population was more tolerant to leaf than to inflorescence *** results indicated no trade-off between trichome production and tolerance,suggesting that these two defense mechanisms have the potential to evolve indepen-dently in this *** population.

关键词： plant defense fitness costs resistance traits defoliation florivory

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New Evidence for a Cretaceous Age for a Mesozoic Nonmarine Bivalve Assemblage from Paekto-dong, Sinuiju City, The Democratic People’s Republic of Korea

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Acta Geologica Sinica(English Edition) 2019年第6期93卷 1607-1613页

作者： CholGuk WON KwangSik SO SuHyang jon Department of Paleontology Faculty of Geology Kim Il Sung University

The Sinuiju Formation in Paekto-dong,Sinuiju City in the Democratic People's Republic of Korea has yielded Mesozoic nonmarine bivalve fossils,which is the first occurrence of such in the *** on these fossil specimens,a new Cretaceous bivalve assemblage,the Arguniella yanshanensis-Sphaerium anderssoni Assemblage is *** assemblage includes Arguniella yanshanensis,*** and Sphaerium anderssoni and can be compared with the Jehol *** age of the Sinuiju Formation is also clarified and on the basis of the bivalves and the presence of a Eosestheria–Ephemeropsis–Lycoptera(E–E–L)assemblage,the formation is not Upper Jurassic,but Lower Cretaceous in age.

关键词： biostratigraphy nonmarine bivalves Sinuiju Formation Early Cretaceous DPRK

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Reducing the loss of genetic diversity associated with assisted colonization-like introductions of animals

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Current Zoology 2015年第5期61卷 827-834页

作者： Jaana KEKKONEN jon E. BROMMER Department of Biosciences University of Helsinki Helsinki Finland Department of Biology University of Turku Turku Finland

Translocations, especially assisted colonizations, of animals are increasingly used as a conservation management tool. In many cases, however, limited funding and other logistic challenges limit the number of individuals available for transloeation. In conservation genetics, small populations are predicted to rapidly lose genetic diversity which can deteriorate population survival. Thus, how worried should we be about the loss of genetic diversity when introducing small, isolated populations？ Historical species introductions provide a means to assess these issues. Here we review 13 studies of ＂assisted colonization-like＂ introductions of animals, where only a small known number of founders established an isolated population without secondary contact to the source population. We test which factors could be important in retaining genetic diversity in these cases. In many cases, loss in heterozygosity （-12.1%） was detected, and more seriously the loss in allelic richness （-27.8 %）. Number of founders seemed to have an effect but it also indicated that high population growth rate could help to retain genetic diversity, i.e. future management actions could be effective even with a limited number of founders if population growth would be enhanced. On the contrary, translocated organisms with longer generation times did not seem to retain more genetic diversity. We advocate that, where possible, future studies on translocated animals should report the loss of genetic diversity （both heterozygosity and allelic richness）, which is essential for meta-analyses like this one for deepening our understanding of the genetic consequences of assisted colonization, and justifying management decisions [Current Zoology 61 （5）： 827-834, 2015].

关键词： Introduced species Loss of genetic diversity Number of founders Conservation management Population growth rate Generation time

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Nanoscale electropolishing of high-purity nickel with an ionic liquid

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International Journal of Minerals,Metallurgy and Materials 2019年第5期26卷 649-656页

作者： jon Derek Loftis Tarek M.Abdel-Fattah Applied Research Center at Thomas Jefferson National Accelerator Facility and Department of Molecular Biology and Chemistry at Christopher Newport University Department of Physical Sciences Virginia Institute of Marine Science College of William and Mary Faculty of Sciences Alexandria University

High purity(>99.9% composition) nickel metal specimens were used in electropolishing treatments with an acid-free ionic liquid electrolyte prepared from quaternary ammonium salts as a green polishing solution. Voltammetry and chronoamperometry tests were conducted to determine the optimum conditions for electrochemical polishing. Atomic force microscopy(AFM) revealed nanoscale effectiveness of each polishing treatment. Atomic force microscopy provided an overall observation of the material interface between the treated and unpolished regions. Surface morphology comparisons summarized electrochemical polishing efficiency by providing root-mean-square roughness averages before and after electrochemical polishing to reveal a mirror finish six times smoother than the same nickel metal surface prior to electropolishing. This transition manifested in a marked change in root-mean-squared roughness from 112.58 nm to 18.64 nm and producing a smooth mirror finish. Finally, the mechanism of the ionic liquid during electropolishing revealed decomposition of choline in the form of a transient choline radical by acceptance of an electron from the nickel-working electrode to decompose to trimethylamine and ethanol.

关键词： electrochemical polishing ionic liquid Ni 2EG:1VB4

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Amine reclaiming technologies in post-combustion carbon dioxide capture

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Journal of Environmental Sciences 2015年第1期27卷 276-289页

作者： Tielin Wang jon Hovland Klaus J.Jens Telemark University College Tel-Tek Porsgrunn 3918 Norway

Amine scrubbing is the most developed technology for carbon dioxide（CO2） *** of amine solvents due to the presence of high levels of oxygen and other impurities in flue gas causes increasing costs and deterioration in long term performance,and therefore purification of the solvents is needed to overcome these problems. This review presents the reclaiming of amine solvents used for post combustion CO2capture（PCC）. Thermal reclaiming, ion exchange, and electrodialysis, although principally developed for sour gas sweetening, have also been tested for CO2 capture from flue *** three technologies all have their strengths and weaknesses, and further development is needed to reduce energy usage and costs. An expected future trend for amine reclamation is to focus on process integration of the current reclaiming technologies into the PCC process in order to drive down costs.

关键词： Carbon dioxide capture Amine reclaiming Distillation Ion exchange Electrodialysis

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