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Modelling of compacted graphite cast iron solidification-Discussion of microstructure parameters

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China Foundry 2020年第2期17卷 144-149页

作者： Jacques Lacaze Urko de la Torre jon sertucha Anna Regordosa Centre Inter-universitaire de Recherche et d’Ingénierie des Matériaux(CIRIMAT) Universitéde ToulouseToulouseFrance Fundación AZTERLAN DurangoSpain

A melt maintained for hours in a press pour unit allowed the following changes over time from spheroidal graphite to compacted graphite iron by casting thermal cups at regular time *** provided extensive experimental information for checking the possibility of simulating solidification of compacted graphite irons by means of a microstructure modelling *** solidification,compacted graphite develops very much as lamellar graphite but with much less *** this basis,a simulation of the thermal analysis records was developed which considers solidification proceeding in a pseudo binary Fe-C *** simulated curves were compared with the experimental ones obtained from three representative alloys that cover the whole microstructure change during the holding of the *** most relevant result is that the parameter describing branching capability of graphite is the most important for reproducing the minimum eutectic temperature and the recalescence which are so characteristic of the solidification of compacted graphite cast irons.

关键词： compacted graphite irons thermal analysis stable eutectic metastable eutectic simulation

厚断面球铁部件凝固过程中蠕虫状石墨形成的热分析

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现代冶金（内蒙古） 2010年第2期 27-34页

作者： jon sertucha[西班牙] 乔林锁(译)

对近共晶球墨铸铁大试块中心的冷却曲线变化进行了分析，通过显微组织观察，给出蠕虫状石墨析出倾向。观察了低于共晶温度后的整个连续凝固过程：1）液态下初生石墨形核；2）奥氏体枝晶包围初生粒子的初始共晶反应过程；3）CHG晶粒大量... 详细信息

对近共晶球墨铸铁大试块中心的冷却曲线变化进行了分析，通过显微组织观察，给出蠕虫状石墨析出倾向。观察了低于共晶温度后的整个连续凝固过程：1）液态下初生石墨形核；2）奥氏体枝晶包围初生粒子的初始共晶反应过程；3）CHG晶粒大量形核和长大，以及第二相粒子的形核和长大，随后第二相粒子形成球状石墨共晶晶粒。共晶反应时，由于蠕虫状石墨的析出，再辉最大值首先增大，然后又减小。最有意义的是观察了由CHG影响的试块体积和由TA样杯检测的再辉之间的关系。

关键词：厚断面铸铁球铁石墨变质蠕虫状石墨热分析

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欧洲铸造业的新发展

欧洲铸造业的新发展

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

第十二届全国铸造年会暨2011中国铸造活动周

作者： Ramón Suárez Gorka Zarrabeitia jon sertucha 阿兹特兰工程及铸造部

随着国际铸造市场需求的不断增加及竞争的日趋激烈,欧洲铸造行业在生产工艺和铸件方面都达到了一个全新的高质量水平。不仅如此,这种高质量水平还使生产成本大幅削减,同时也满足了欧盟国家对铸造行业的环保要求。事实上,这几方面的要求...

随着国际铸造市场需求的不断增加及竞争的日趋激烈,欧洲铸造行业在生产工艺和铸件方面都达到了一个全新的高质量水平。不仅如此,这种高质量水平还使生产成本大幅削减,同时也满足了欧盟国家对铸造行业的环保要求。事实上,这几方面的要求也正是欧洲铸造业未来和发展的挑战,因此铸造厂家都在竭尽全力提高自己的铸造技术,加深对铸造原材料的了解。阿兹特兰中心就参与了许多客户在这方面的研究项目,例如:如何根据凝固过程来测量和控制熔融金属质量;具备更高机械性能的新等级铸造用铁的研究;模型板产量的提高（减少补缩系统）;铸件运送客户前对不增值操作流程的去除;加工过程中变量的改善及对变化结果的预计,从而稳定生产过程;铸件缺陷最小化;可替代原材料的灵活运用;降低能源成本等等。到目前为止,欧洲一些铸造厂家已经成功实现了以上研究项目,在铸造业发展方面占据了领先水平。

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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

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

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

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

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

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