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A charge-density-based general cation insertion algorithm for generating new Li-ion cathode materials

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npj Computational Materials 2020年第1期6卷 336-342页

作者： Jimmy-Xuan Shen Matthew Horton Kristin A.persson Department of Materials Science and Engineering University of CaliforniaBerkeleyBerkeleyCA 94720USA Energy Technologies Area Lawrence Berkeley National LaboratoryBerkeley 94720USA

Future lithium(Li)energy storage technologies,in particular solid-state configurations with a Li metal anode,opens up the possibility of using cathode materials that do not necessarily contain Li in its as-made *** accelerate the discovery and design of such materials,we develop a general,chemically,and structurally agnostic methodology for identifying the optimal Li sites in any crystalline *** a given crystal structure,we attempt multiple Li insertions at symmetrically in-equivalent positions by analyzing the electronic charge density obtained from first-principles density functional *** this report,we demonstrate the effectiveness of this procedure in successfully identifying the positions of the Li ion in well-known cathode materials using only the empty host(charged)material as ***,applying the algorithm to over 2000 candidate cathode empty host materials we obtain statistics of Li site preferences to guide future developments of novel Li-ion cathode materials,particularly for solid-state applications.

关键词： charge insertion algorithm

Emissions and deposit properties from combustion of wood pellet with magnesium additives

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燃料化学学报 2013年第5期41卷 530-539页

作者： Tomas persson Jochen Riedel Jonas Berghel Ulf Bexell Kaung Myat Win School of Technology and Business Studies Dalarna University Department of Energy Environmental and Building TechnologyKarlstad University

This work studies the amount of gaseous and particle emissions and deposits on heat exchanger surfaces in a boiler firedwith commercially available pellets and with pellets primed with magnesium oxide and magnesium *** combustionexperiments were performed on a residential boiler of 20 *** placed in the heat exchanger was analysed with SEM-EDX-mapping to evaluate the chemical composition of the *** results show that particle emissions(PM 2.5)using the additivesincreased by about 50%and the mass of the deposits in the flue gas heat exchanger(excluding loose fly ash)increased by about25%compared to the combustion of pellets without *** amount of additives was found to be eight times higher than theamount of the main alkali metals potassium(K)and sodium(Na)which leads to the assumption that the additives were overdosedand therefore caused the problems *** SEM analysis of the substrates placed in the flue gas heat exchanger indicate that thedeposits of sodium(Na),potassium(K),chlorine(Cl)and sulphur(S)decrease using the *** this was due to theexpected chemical reactions or due to the loose fly ash covering the substrates after the test,could not be determined in this study.

关键词： softwood pellets magnesium additives particle emissions deposit formation

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Rubber–ice friction

Friction 2023年第8期11卷 1534-1543页

作者： Toshi TADA Satoshi KAWASAKI Ryouske SHIMIZU Bo N.J.persson Sumitomo Rubber Industries Ltd.Material Research&Development HQ.2-1-1Kobe 651-0071Japan Peter Grünberg Institute(PGI-1) Forschungszentrum JülichJülich 52425Germany MultiscaleConsulting Jülich 52428Germany

We study the friction when a rectangular tire tread rubber block is sliding on an ice surface at different temperatures ranging from−38 to−2℃,and sliding speeds ranging from 3μm/s to 1 cm/*** low temperatures and low sliding speeds we propose that an important contribution to the friction force is due to slip between the ice surface and ice fragments attached to the rubber *** temperatures above−10℃ or for high enough sliding speeds,a thin premelted water film occurs on the ice surface and the contribution to the friction from shearing the area of real contact is *** this case the dominant contribution to the friction force comes from viscoelastic deformations of the rubber by the ice *** comment on the role of waxing on the friction between skis and snow(ice particles).

关键词： ice friction rubber friction ice premelting

Topgrafting as a tool in operational Scots pine breeding

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Journal of Forestry Research 2024年第6期35卷 160-172页

作者： Alisa Heuchel David Hall Curt Almqvist Ulfstand Wennström Torgny persson Department of Ecology and Environmental Science UmeåPlant Science CenterUmeåUniversity90187 UmeåSweden The Forestry Research Institute of Sweden(Skogforsk) P.O.Box 391821 SävarSweden

Effective breeding requires multiplying desired genotypes,keeping them at a convenient location to perform crosses more efficiently,and building orchards to generate material for *** some of these aims can be achieved by conventional grafting involving only rootstock and scion,topgrafting is known to deliver all in a shorter time *** this study,Scots pine scions were grafted onto the upper and lower tree crowns in two clonal archives with the aim of inducing early female and male strobili produc-tion,*** survival rates and strobili production were analyzed with generalized linear mixed ***-vival was low(14%)to moderate(41%),and mainly affected by the topgraft genotype,interstock genotype,crown posi-tion and weather conditions in connection with the grafting *** was not affected by the cardinal position in the crown(south or north).Male flowering was ample three years after grafting and reached 56%in the first year among live scions,increasing to 62 and 59%in consecutive *** flowering was scarce and was 9%at first,later increasing to 26 and 20%of living scions but was strongly affected by the topgraft *** one subset of scions,female flowering was observed 1 year after ***,flowering success was mainly affected by the topgraft and interstock genotypes,and secondary growth of *** is one of few reports on topgrafting in functional Scots pine clonal archives.

关键词： Pinus sylvestris Conifer breeding Flowering stimulation Topgrafting

Carbon Supply and the Regulation of Cell Wa Synthesis

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Molecular Plant 2018年第1期11卷 75-94页

作者： Jana Verbancic John Edward Lunn Mark Stitt Staffan persson Max Planck Institute of Molecular Plant Physiology Am Muhlenberg 1 14476 Potsdam-Golm Germany School of Biosciences University of Melbourne Parkville VIC 3010 Australia

All plant cells are surrounded by a cell wall that determines the directionality of cell growth and protects the cell against its environment. Plant cell walls are comprised primarily of polysaccharides and represent the largest sink for photosynthetically fixed carbon, both for individual plants and in the terrestrial biosphere as a whole. Cell wall synthesis is a highly sophisticated process, involving multiple enzymes and metabolic intermediates, intracellular trafficking of proteins and cell wall precursors, assembly of cell wall polymers into the extracellular matrix, remodeling of polymers and their interactions, and recycling of cell wall sugars. In this review we discuss how newly fixed carbon, in the form of UDP-glucose and other nucleotide sugars, contributes to the synthesis of cell wall polysaccharides, and how cell wall synthesis is influenced by the carbon status of the plant, with a focus on the model species Arabidopsis （Arabidopsis thaliana）.

关键词： carbon availability cell walls nucleotide sugars sucrose synthase

T-DNA-Induced Chromosomal Translocations in feronia and anxur2 Mutants Reveal Implications for the Mechanism of Collapsed Pollen Due to Chromosomal Rearrangements

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Molecular Plant 2014年第10期7卷 1591-1594页

作者： Colin Ruprecht[a],, Andrew Carroll[b] Staffan persson[a],[c], a Max-Planck-Institute for Molecular Plant Physiology Am Muehlenberg 1 14476 Potsdam Germanyb Department of Biology Stanford University Stanford CA 94305 USAc ARC Centre of Excellence in Plant Cell Walls School of Botany University of Melbourne Parkville 3010 Victoria Australia

Dear Editor, Approximately every fifth Arabidopsis T-DNA inser- tion line contains chromosomal translocations caused by the inserted T-DNA （Clark and Krysan, 2010）. Albeit broad use of T-DNA lines for mutant analysis, little is known about the consequences of these chromosomal rearrangements and only a few studies describe chromosomal aberrations in the mutant lines. While plant growth in general is not affected by such chromosomal translocations, defects in gametophyte development have been observed in lines that are heterozygous for the T-DNA insertion （Ray et al., 1997; Curtis et al., 2009）.

关键词： T-DNA插入染色体易位染色体重排突变系体显示苹果属机制花粉

Noble gas as a functional dopant in ZnO

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npj Computational Materials 2019年第1期5卷 822-827页

作者： Oleksandr I.Malyi Kostiantyn V.Sopiha Clas persson Centre for Materials Science and Nanotechnology Department of PhysicsUniversity of OsloP.O.Box 1048BlindernNO-0316 OsloNorway Ångström Solar Center Solid State ElectronicsDepartment of Engineering SciencesUppsala UniversityBox 534SE-75121 UppsalaSweden

Owing to fully occupied orbitals,noble gases are considered to be chemically inert and to have limited effect on materials properties under standard ***,using first-principles calculations,we demonstrate herein that the insertion of noble gas(***,Ne,or Ar)in ZnO results in local destabilization of electron density of the material driven by minimization of an unfavorable overlap of atomic orbitals of the noble gas and its surrounding ***,the noble gas defect(interstitial or substitutional)in ZnO pushes the electron density of its surrounding atoms away from the ***,the host material confines the electron density of the noble *** a consequence,the interaction of He,Ne,or Ar with O vacancies of ZnO in different charge states q(ZnO:VO^(q))affects the vacancy stability and their electronic ***,we find that the noble gas is a functional dopant that can delocalize the deep in-gap VO^(q) states and lift electrons associated with the vacancy to the conduction band.

关键词： dopant noble vacancy

Improving rail vehicle dynamic performance with active suspension

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High-Speed Railway 2023年第1期1卷 23-30页

作者： Sebastian Stichel Rickard persson Rocco Giossi KTH Royal Institute of Technology KTH Railway GroupTeknikringen 8S-10044 StockholmSweden

Today,it is difficult to further improve the dynamic performance of rail vehicles with conventional passive ***,simplified vehicle respectively running gear layouts that significantly could reduce vehicle weights are difficult to realize with modern requirements on passenger vibration comfort and wheel and rail *** suspension is a powerful technology that can improve the vehicle dynamic performance and make simplified vehicle concepts *** KTH Railway group has,together with external partners,investigated active suspensions both numerically and experimentally for 15 *** paper provides a summary of the activities and the most important *** major project carried out in close collaboration with the vehicle manufacturer Bombardier and the Swedish Transport Administration was the Green Train project,where a 2-car EMU test bench was used to demonstrate different active *** ongoing projects,a concept of single axle-single suspension running gear is developed with active suspension both for comfort improvement and reduced wheel wear in *** results from on-track tests in the Green Train project were so good that the technology is now implemented in commercial trains and the simulation results for the single-axle running gear are very promising.

关键词： Rail Vehicle dynamics Active suspension Ride comfort Active wheelset steering Wheel wear

High-throughput prediction of the ground-state collinear magnetic order of inorganic materials using Density Functional Theory

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npj Computational Materials 2019年第1期5卷 588-598页

作者： Matthew Kristofer Horton Joseph Harold Montoya Miao Liu Kristin Aslaug persson Energy Technologies Area Lawrence Berkeley National LaboratoryBerkeleyCAUSA Institute of Physics Chinese Academy of SciencesBeijingChina Department of Materials Science University of California BerkeleyBerkeleyCA 94720USA

We present a robust,automatic high-throughput workflow for the calculation of magnetic ground state of solid-state inorganic crystals,whether ferromagnetic,antiferromagnetic or ferrimagnetic,and their associated magnetic moments within the framework of collinear spin-polarized Density Functional *** is done through a computationally efficient scheme whereby plausible magnetic orderings are first enumerated and prioritized based on symmetry,and then relaxed and their energies determined through conventional DFT+U *** automated workflow is formalized using the atomate code for reliable,systematic use at a scale appropriate for thousands of materials and is fully *** performance of the workflow is evaluated against a benchmark of 64 experimentally known mostly ionic magnetic materials of non-trivial magnetic order and by the calculation of over 500 distinct magnetic orderings.A non-ferromagnetic ground state is correctly predicted in 95% of the benchmark materials,with the experimentally determined ground state ordering found exactly in over 60% of *** of the ground state magnetic order at scale opens up the possibility of high-throughput screening studies based on magnetic properties,thereby accelerating discovery and understanding of new functional materials.

关键词： state ground ferromagnetic