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Trace element characteristics of partial melts produced by melting of metabasalts at high pressures: Constraints on the formation condition of adakitic melts

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Science China Earth Sciences 2006年第9期49卷 915-925页

作者： J. adam T.H. Green GEMOC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia GEMOC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

Experiments were conducted on a natural basalt (with 5 wt.% added H2O) at 1.0―2.5 GPa and 900―1100℃. Experimental products include partial melts (quenched glasses) + residual mineral assemblages of amphibolite or eclogite. Electron microprobe and LAM-ICP-MS were used to determine major and trace element compositions of these quenched melts, respectively. Major ele- ment compositions of all the melts are tonalitic- trondhjemitic, similar to adakite. Their trace element characteristics are controlled by coexisting residual minerals. Signatures of adakite such as high Sr/Y, low HREE and negative Nb-Ta anomaly, etc. are present only in the melts coexisting with residual assemblages containing rutile and garnet (rutile-bearing eclogite or rutile-bearing amphibole-eclogite). Garnet leads to HREE depletion in melts, whereas rutile controls Nb and Ta partitioning during the partial melting and causes negative Nb-Ta anomaly in melts. Therefore, in addition to garnet, rutile is also a necessary residual phase during the generation of adakite or TTG magmas to account for the negative Nb-Ta anomaly of the magmas. The depth for the generation of adakite/TTG magmas via melting of metabasalt must be more than about 50 km based on the approximate 1.5 GPa mini- mum-pressure for rutile stability in the partial melting field of hydrous basalt.

关键词： trace element adakite/TTG magmas partial melting of metabasalt negativeNb-Ta anomaly rutile

Energy Aspects of CO_2 Sorption in the Context of Sequestration in Coal Deposits

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Journal of Earth Science 2014年第4期25卷 719-726页

作者： Pawe Baran Katarzyna Zarebska adam Nodzeński AGH University of Science and Technology Faculty of Energy and Fuels Al. Mickiewicza 30 30-059 Kraków Poland

This paper summarises the results of experimental testing of carbon dioxide sorption on five coal samples. Sorption tests were done at the temperature 288, 298, 313 and 323 K, in the pressure range 0-5 MPa. The analysis of sorption isotherms and the effects of temperature on sorption capacity reveal that in the case of samples NR1, Pn, Tu, Be the temperature increase from 298 to 323 K led to 1.3-fold decrease of the sorption value. In the ease of coal Th the decrease of sorption capacity was 3-fold. It appears that the analysis of maceral content plays a major role. In the case of coals, porosity is associated with the petrographic composition. The values of the isosteric heat of sorption and the work of expansion and desorption were derived for the investigated sorption systems. Test data reveal that for hard coals the isosteric heat is inversely proportional to the ＂reserve＂ of volumetric work-a major parameter triggering the sudden release of gas from the coalbed, thus enabling us to assess the potential risk involved in rapid unsealing of the coalbed.

关键词： coal carbon dioxide sequestration sorption energy isosteric heat.

含有硅酸钙和磷酸钠的新型牙膏对牙本质小管封闭作用的体外研究

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口腔护理用品工业 2024年第5期34卷 26-31页

作者：李昊择刘炜宁周奂君孙岳魁张美丽王进防 adam Limerb Gareth Owensb Andrew Joinerb 联合利华口腔护理中国研发中心临新路66号上海200335 联合利华口腔护理英国研发中心 Quamy Road EastBebingtonWiral CH633JWUnited Kingdom

通过体外实验,对含有硅酸钙和磷酸钠的新型含氟牙膏在缓解牙齿敏感方面进行研究,并探讨其作用机理。实验结果显示,经过数次体外刷牙处理后,活性物颗粒能够有效地沉积到牙本质表面和牙小管内部,在封闭牙本质小管的同时,诱导再矿化形成羟... 详细信息

通过体外实验,对含有硅酸钙和磷酸钠的新型含氟牙膏在缓解牙齿敏感方面进行研究,并探讨其作用机理。实验结果显示,经过数次体外刷牙处理后,活性物颗粒能够有效地沉积到牙本质表面和牙小管内部,在封闭牙本质小管的同时,诱导再矿化形成羟基磷灰石,所形成的矿化物能够有效地抵抗外部酸蚀。这种新型牙膏具有缓解牙齿敏感和保护牙本质抵抗酸蚀的潜在功效。

关键词：硅酸钙磷酸钠牙本质过敏症羟基磷灰石牙膏

SOLUTION OF OPTIMAL TR A NSPORTATION PROBLEMS USING A MULTIGRID LINEAR PROGR AMMING APPROACH

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Journal of Computational Mathematics 2020年第6期38卷 933-951页

作者： adam M.Oberman Yuanlong Ruan Department of Mathematics McGill UniversityMontrealCanada Department of Mathematics Beihang UniversityBeijing 100191China

We compute and visualize solutions to the Optimal Transportation(OT)problem for a wide class of cost *** standard linear programming(LP)discretization of the continuous problem becomes intractable for moderate grid sizes.A grid refinement method results in a linear cost *** convergence of solutions is established and barycentric projection of transference plans is used to improve the accuracy of *** maps between nonconvex domains,partial OT free boundaries,and high accuracy barycenters are presented.

关键词： Optimal Transportation Linear Programming Monge-Kantorovich Barycenter.

Risk of Flash Floods in Urban and Rural Municipalities Triggered by Intense Precipitation in Wielkopolska of Poland

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International Journal of Disaster Risk Science 2023年第3期14卷 440-457页

作者： Iwona Pińskwar adam Choryński Dariusz Graczyk Department of Land Improvement Environmental Development and Spatial ManagementFaculty of Environmental Engineering and Mechanical EngineeringPoznan University of Life Sciences60-649 PoznanPoland Meteorology Laboratory Department of Construction and GeoengineeringFaculty of Environmental Engineering and Mechanical EngineeringPoznan University of Life Sciences60-649 PoznanPoland

This research analyzed interventions of State Fire Service(SFS)units in the Wielkopolska region of Poland that were triggered by extreme precipitation for the period *** results demonstrated that the most populated and urbanized towns in the Wielkopolska(Greater Poland,west of Warsaw)region are at the most risk in the event of extreme precipitation occurrence as measured by the total number of interventions made by the *** number of SFS unit interventions in towns,standardized to 10,000 inhabitants,indicates that the highest proportional volume of interventions also occurred in smaller *** the rural municipalities the number of SFS unit interventions increases along with higher population density and proportion of infrastructure *** analyzed in this study,the 12 years from 2010 to 2021 were characterized by a higher number of days with heavy precipitation,for example,20,30,40,and 50 mm,in comparison to the previous periods 1961-2010 and *** databases collected by emergency services are a valuable source of information for hazard *** on those and other available data,a statistical model was created and factors influencing the local and regional occurrence of interventions were *** suburbanization,the rising proportion of impermeable surfaces,and the impact of climate change are of considerable importance in urban flood *** is necessary to help municipalities develop abilities to absorb larger amounts of rainwater.

关键词： Flash flood risk Poland Risk exposure Social vulnerability State Fire Service Wielkopolska

Materials structure genealogy and high-throughput topological classification of surfaces and 2D materials

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npj Computational Materials 2018年第1期4卷 222-231页

作者： Lauri Himanen Patrick Rinke adam Stuart Foster Department of Applied Physics Aalto UniversityP.O.Box 1110000076 AaltoEspooFinland Graduate School Materials Science in Mainz Staudinger Weg 9Mainz 55128Germany WPI Nano Life Science Institute(WPI-NanoLSI) Kanazawa UniversityKakuma-machiKanazawa 920-1192Japan

Automated and verifiable structural classification for atomistic structures is becoming necessary to cope with the vast amount of information stored in various computational materials *** we present a general recursive scheme for the structural classification of atomistic systems and introduce a structural materials map that can be used to organize the materials structure *** also introduce our implementation for the automatic classification of two-dimensional structures,especially focusing on surfaces and 2D *** classification procedure can automatically determine the dimensionality of a structure,further categorize the structure as a surface or a 2D material,return the underlying unit cell and also identify the outlier atoms,such as *** classification scheme does not require explicit search patterns and works even in the presence of defects and *** classification is tested on a wide variety of atomistic structures and provides a high-accuracy determination for all of the returned structural properties.A software implementation of the classification algorithm is freely available with an opensource license.

关键词： structure return becoming

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杀人鸟鹤鸵地球上最后的恐龙？

环球人文地理 2024年第9期 70-77页

作者：鲨鲨 ms＿pics＿and＿more luismicss SALTY RIVER karegg Arjan diegograndi wagner＿md adam Debra electra kay-smith Zorro Stock images

科学研究表明，这种能吞火炭，能杀人，得到过吉尼斯世界纪录认证的大鸟，也许是地球上最后的恐龙。6500万年前，恐龙的足迹终结在那场白垩纪-古近纪灭绝事件中，斗转星移，其中的一部分生物进化至今，演变成了近万种鸟类。鹤鸵就是其...

科学研究表明，这种能吞火炭，能杀人，得到过吉尼斯世界纪录认证的大鸟，也许是地球上最后的恐龙。6500万年前，恐龙的足迹终结在那场白垩纪-古近纪灭绝事件中，斗转星移，其中的一部分生物进化至今，演变成了近万种鸟类。鹤鸵就是其中一种。它们生活在巴布亚新几内亚森林深处，就像恐龙世界最后的碎片。

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Cutting the Gordian knot： Complex signaling in African cichlids is more than multimodal

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Current Zoology 2011年第2期57卷 237-252页

作者： Moira J. VAN STAADEN adam R. SMITH Department of Biological Sciences and JP Scott Center for Neuroscience Mind & Behavior Bowling Green State University OH 43403 USA Department of Biology University of Maryland College Park Maryland 20742 USA

The active transmission of information from sender to receiver is a fundamental component of communication, and is therefore a primary facet in evolutionary models of sexual selection. Research in several systems has underlined the importance of multiple sensory modalities in courtship signals. However, we still tend to think of individuals as having a relatively static signal in consecutive communicative events. While this may be true for certain traits such as body size or coloration, behaviorally modulated signals can quickly violate this assumption. In this work, we explore how intraspecific variation may be an important component of interspecific signal divergence using cichlid fishes from Lake Malawi. Behavioral analyses were made using six species of Malawian cichlids from two divergent genera. While interspecific differences were found between congeners based on species-level analyses of both acoustic and audiovisual signals, intraspecific variation was of a similar magnitude. Specifically, individual fishes were found to possess highly plastic signal repertoires. This finding was ubiquitous across all species and resuited in a great deal of overlap between heterospecific individuals, despite statistically distinct species means. These results demonstrate that some aspects of courtship in Malawian cichlids are more plastic than previously proposed, and that studies must account for signal variability within individuals. We propose here that behavioral variability in signaling is important in determining the communication landscape on which signals are perceived. We review potential complexity deriving from multimodal signaling, discuss the sources for such lability, and suggest ways in which this issue may be approached experimentally .

关键词： Cichlid Motivation Intraspecific variability Mate preference Multimodal

CONVERGENCE AND OPTIMALITY OF ADAPTIVE MIXED METHODS FOR POISSON’S EQUATION IN THE FEEC FRAMEWORK

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Journal of Computational Mathematics 2020年第5期38卷 748-767页

作者： Michael Holst Yuwen Li adam Mihalik Ryan Szypowski Department of Mathematics University of CaliforniaSan DiegoCA 92123USA Department of Mathematics and Statistics Cal Poly PomonaUSA

Finite Element Exterior Calculus (FEEC) was developed by Arnold, Falk, Winther andothers over the last decade to exploit the observation that mixed variational problems canbe posed on a Hilbert complex, and Galerkin-type mixed methods can then be obtained bysolving finite-dimensional subcomplex problems. Chen, Holst, and Xu (Math. Comp. 78(2009) 35–53) established convergence and optimality of an adaptive mixed finite elementmethod using Raviart–Thomas or Brezzi–Douglas–Marini elements for Poisson’s equationon contractible domains in R^2, which can be viewed as a boundary problem on the deRham complex. Recently Demlow and Hirani (Found. Math. Comput. 14 (2014) 1337–1371) developed fundamental tools for a posteriori analysis on the de Rham *** this paper, we use tools in FEEC to construct convergence and complexity resultson domains with general topology and spatial dimension. In particular, we construct areliable and efficient error estimator and a sharper quasi-orthogonality result using a noveltechnique. Without marking for data oscillation, our adaptive method is a contractionwith respect to a total error incorporating the error estimator and data oscillation.

关键词： Finite Element Exterior Calculus Adaptive finite element methods A posteriori error estimates,Convergence Quasi-optimality