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External stimuli controlled multiferroic charge-transfer crystals

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Nano Research 2016年第4期9卷 925-932页

作者： Wei Qin Xiaomin Chen Jessica Lohrman Maogang Gong Guoliang Yuan manfred Wuttig Shenqiang Ren Department of Mechanical Engineering Temple University Philadelphia Pennsylvania 19122 USA Department of Matefials Science and Engineering University of Maryland College Park Maryland 20742 USA School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China Department of Chemistry University of Kansas Lawrence Kansas 66045 USA

Multiferroic charge-transfer crystals have drawn significant interest due to their simultaneous dipolar and spin ordering. Numerous theoretical and experimental studies have shown that the molecular stacking between donor and acceptor complexes plays an important role in tuning charge-transfer enabled multifunctionality. Herein, we show that the charge-transfer interactions can be controlled by the segregated stack, consisting of polythiophene donor- and fuUerene acceptor-based all-conjugated block copolymers. Room temperature magnetic field effects, ferroelectricity, and anisotropic magnetism are observed in charge-transfer crystals, which can be further controlled by photoexcitation and charge doping. Furthermore, the charge-transfer segregated stack crystals demonstrate external stimuli controlled polarization and magnetization, which opens up their multifunctional applications for all-organic multiferroics.

关键词： organic multiferroics charge-transfer room temperature block copolymer

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L'Arme secrète

法语学习 2001年第5期 11-12页

作者： Claude et Jacqueline held

The phylogeny of selected Phylloporus species,inferred from NUC-LSU and ITS sequences,and descriptions of new species from the Old World

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Fungal Diversity 2012年第4期55卷 109-123页

作者： Maria Alice Neves manfred Binder Roy Halling David Hibbett Kasem Soytong Departamento de Botânica Universidade Federal de Santa CatarinaFlorianópolisSC 88040-900Brazil Biology Department Lasry Center for BiosciencesClark University15 Maywood StreetWorcesterMA 01601USA Institute of Systematic Botany The New York Botanical GardenBronxNY 10458-5126USA Faculty of Agricultural Technology King Mongkut’s Institute of TechnologyLadkrabangBangkokThailand

The phylogeny of Phylloporus(Boletaceae)has not been well studied,and the taxonomic relationships of this genus have varied considerably among *** following study presents phylogenetic relationships of Phylloporus based on two nuclear ribosomal DNA regions,ITS and *** ITS dataset includes 39 collections and the LSU dataset contains 50 collections of Phylloporus.A combined analysis of both genes did not resolve the deeper nodes in the phylogeny,but the results suggest that Phylloporus is monophyletic and a sister group of the Xerocomus subtomentosus *** lamellate hymenophore configuration is a synapomorphy that distinguishes Phylloporus from the other genera in the *** placement of a lamellate genus within Boletaceae suggests that hymenophore evolution is not well understood in the *** is the first phylogeny of Phylloporus and includes 20 species from different geographic *** taxa of Phylloporus from the Old World are here *** cyanescens is a new combination for an Australasian taxon formerly named as a variety of ***(Massee)*** pumilus is described from Indonesia,and 4 species are described from Thailand:***,***,***,and ***.

关键词： Boletaceae Agaricomycotina Taxonomy Distribution

Spatial and temporal variability of soil water in drylands:plant water potential as a diagnostic tool

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Forestry Studies in China 2008年第2期10卷 74-80页

作者： Maik VESTE Markus STAUDINGER manfred KüPPERS Research Center for Landscape Development and Mining Landscapes Brandenburg University of TechnologyCottbus D-03046Germany Institute of Botany and Botanical GardenUniversity of HohenheimStuttgart D-70599Germany AVL-ARGE Vegetation Ecology and Landscape Planing GmbH Wien A-1060Austria Institute of Botany and Botanical Garden University of HohenheimStuttgart D-70599Germany

Arid and semi-arid regions are characterized by low rainfall and high potential evaporative demand. Here, water is the major limiting factor for plant growth and productivity. Soil and surface hydrology properties （e.g. field capacity, infikration rates） effectively control the water re-distribution in the ecosystem, a fact that is aggravated in arid environments. Information of the spatial and temporal accessibility of soil water in desert ecosystems is limited. The purpose of the studies is the application of plant water potential to estimate the spatial and temporal variations of soil water availability in different arid ecosystems of the Negev （Israel） and southern Morocco. As model plants the evergreen shrubs Retama raetam, Thymelaea hirsuta and trees （Acacia tortilis） were chosen. Seasonal and spatial variations of the pre-dawn water potential （ψpd） were examined as diagnostic tool to determine water availability on the landscape level. The seasonal differences in the pre-dawn water potential were less pronounced on the dune compared to the interdune. This showed a better water availability on the dune slope. Also in the investigated wadis systems spatial differences of the water potential could be detected and related to the vegetation pattern.

关键词： soil water pattern predawn potential deserts Nizzana Negev

德国南部落叶阔叶林下常见植物的光适应性研究——以德国Kraichtal地区落叶阔叶林为例

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Acta Botanica Sinica 2001年第9期43卷 960-966页

作者：江源 manfred MEURER 北京师范大学资源科学研究所 Institute of Geography and Geoecology

通过在 13个样地中测定林下相对照度和多个植物物种的盖度指标 ,建立了林下相对照度与林下植物盖度变化的相关关系 ,对德国南部落叶阔叶林下 12种植物的光适应性进行了分析。结合植物的生态因子指示值和种在群落中的恒有度等生态指标 ,... 详细信息

通过在 13个样地中测定林下相对照度和多个植物物种的盖度指标 ,建立了林下相对照度与林下植物盖度变化的相关关系 ,对德国南部落叶阔叶林下 12种植物的光适应性进行了分析。结合植物的生态因子指示值和种在群落中的恒有度等生态指标 ,探讨了林下植物群落地位的形成原因。结果表明 :1)在散射光条件下进行森林群落中的光照分布特征测定 ,能够降低光斑造成的干扰 ,获得相对稳定的光分布 ;2 )在被研究的 12个物种中 ,有 9种植物在林下的分布与光照条件相关显著 ,其中 7种植物的盖度与相对照度之间具有正相关关系 ,2种植物具有负相关关系。其余 3种植物的盖度与相对照度之间无显著的线性相关 ;3)与光指示值相比 ,盖度与照度之间关系的定量分析能够更清楚地反映林下植物的光适应性 ,揭示植物的光生态幅特征 ;4)光适应性直接影响着林下植物的种间关系 ,也影响着物种的群落地位和作用。光生态幅广的植物 ,在群落中具有较强的适应能力 ,因此能够在多种群落类型中出现 ,表现出较高的恒有度值。

关键词：德国南部植物光适应性指示值种间关系落叶阔叶林林下植物

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Truth & Dare

世界建筑导报 1999年第S1期14卷 8-11页

作者： WeronicaRonnefalk AgnetaEriksson-heldén

Rupert Gardner was born in the County of Kent in southerm *** was educated at Canterbury College ofArchltectureand at the Royal College of Art in London with tutors such asNorman Foster and James Stirling,amongst others After that he worked for Ricardo Bofill's office Taller de arquitectura in Barcelona He settled in Sweden in 1976 and started Rupert GardnerDesign AB in

关键词：餐馆项目介绍上图

Why implantation of bio-loggers may improve our understanding of how animals cope within their natural environment

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Integrative Zoology 2019年第1期14卷 48-64页

作者： Marie-Amélie FORIN-WIART manfred R.ENSTIPP Yvon LE MAHO Yves HANDRICH Universitéde Strasbourg CNRSIPHCDépartement EcologiePhysiologie et EthologieUMR 7178StrasbourgFrance Centre d’Etudes Biologiques de Chizé CNRSUMR 7372Villiers en BoisFrance Centre Scientifique de Monaco Département de Biologie PolaireMonaco

Bio-loggers are miniaturized autonomous devices that record quantitative data on the state of free-ranging ani-mals(***,position and physiology)and their natural *** is especially relevant for spe-cies where direct visual observation is difficult or ***,ongoing technical development allows the monitoring of numerous parameters in an increasing range of species over extended ***,the ex-ternal attachment of devices might affect various aspects of animal performance(energetics,thermoregulation,foraging as well as social and reproductive behavior),which ultimately affect *** attachment might also increase entanglement risk and the conspicuousness of animals,leaving them more vulnerable to *** contrast,implantation of devices can mitigate many of these undesirable effects and might be prefera-ble,especially for long-term studies,provided that the many challenges associated with surgical procedures can be *** may then allow us to gather data that would be impossible to obtain otherwise and thereby may provide new and ecologically relevant insights into the life of wild ***,we:(i)discuss the pros and cons of attachment methods;(ii)highlight recent field studies that used implanted bio-loggers to address eco-physiological questions in a wide range of species;and(iii)discuss logger implantation in light of ethical considerations.

关键词： behavior bio-logging device implantation eco-physiology long-term deployment

Electronic properties of wurtzite GaAs： A correlated structural, optical, and theoretical analysis of the same polytypic GaAs nanowire

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Nano Research 2018年第9期11卷 4708-4721页

作者： Alexander Senichev Pierre Corfdir Oliver Brandt manfred Ramsteiner Steffen Breuer Jorg Schilling Lutz Geelhaar Peter Werner Max-Planck-lnstitut fur Mikrostrukturl)hysik Halle 06120 Germany PauI-Drude-lnstitut for Festkorperelektronik Berlin 10117 Germany Centre for Innovation Competence SiLi-nano Martin-Luther-Universitat Halle 06120 Germany Present address: Birck Nanotechnology Center Purdue University West Lafayette Indiana 47907 USA Present address: Fraunhofer HHI Berlin 10587 Germany Present address: ABB Corporate Research Baden-Dattwi15405 Switzerland

III-V compound semiconductor nanowires are generally characterized by the coexistence of zincblende and wurtzite structures. So far, this polytypism has impeded the determination of the electronic properties of the metastable wurtzite phase of GaAs, which thus remain highly controversial. In an effort to obtain new insights into this topic, we cross-correlate nanoscale spectral imaging by near-field scanning optical microscopy with a transmission electron microscopy analysis of the very same polytypic GaAs nanowire dispersed onto a Si wafer. Thus, spatially resolved photoluminescence spectra could be unambiguously assigned to nanowire segments whose structure is known with lattice-resolved accuracy. An emission energy of 1.528 eV was observed from extended zincblende segments, revealing that the dispersed nanowire was under uniaxial strain presumably due to interaction with its supporting substrate. These crucial information and the emission energy obtained for extended pure wurtzite segments were used to perform envelope function calculations of zincblende quantum disks in a wurtzite matrix as well as the inverse structure. In these calculations, we varied the fundamental bandgap, the electron mass, and the band offset between zincblende and wurtzite GaAs. From this multi-parameter comparison with the experimental data, we deduced that the bandgap between the F8 conduction and A valence band ranges from 1.532 to 1.539 eV in strain-free wurtzite GaAs, and estimated values of 1.507 to 1.514 eV for the F7-A bandgap.

关键词： nanowires crystal-phase quantumstructures wurtzite GaAs strain near-field scanning optical microscopy photoluminescence

Environmental control of daily stem radius increment in the montane conifer Cedrus libani

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Journal of Forestry Research 2020年第4期31卷 1159-1171页

作者： Aylin Güney Serkan Gülsoy Ozdemir Sentürk Armin Niessner manfred Küppers Institute of Botany University of HohenheimStuttgartGermany Faculty of Forestry Isparta University of Applied SciencesIspartaTurkey Golhisar Vocational School Burdur Mehmet Akif Ersoy UniversityBurdurTurkey

Growth response of conifers is species-specific and depends on site and climate *** on daily radial stem growth use different analytical approaches to determine species reactions to environmental *** results contribute to improve forecasts of tree growth under a changing *** 2013 and2014,radial stem growth of 33 mature Cedrus libani individuals growing under different climatic conditions in Turkey and Germany was monitored hourly using high precision point *** radius increments(SRI)were extracted from dendrometer *** annual course of SRI showed site-specific patterns with mean daily values ranging between 9.9 and 29.3μm over the growing *** and principal component analyses indicated that humidity and low temperatures during the growing season favored *** regression analyses demonstrated that precipitation and relative air humidity were the most important factors influencing daily ***-growth relationships were further evaluated using the regression tree *** was the most significant factor on daily SRI for all *** close coupling of SRI to relative air humidity and precipitation underlines the importance of stem water status for radial stem growth of *** which is native to regions with summer *** further explains the superior growth of *** in Germany.

关键词： CART Climate-growth relationship Dendrometer Lebanon cedar Regression tree