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Journal of Materials science & Technology 2015年第9期31卷 881-887页

作者： Camelia Matei Ghimbeu Aleksandr I.Egunov andrey s.ryzhikov Valeriy A.Luchnikov Institut de science des Matériaux de Mulhouse

Ensembles of freeze-dried self-rolled polymer micro-scrolls are explored as template media for produc- ing carbon-iron based composites with fibrous morphology. Polymer fibres impregnated with furfuryl alcohol and loaded with Fe2O3 particles, were thermally treated under inert atmosphere at 700 ℃ and subsequently analysed by scanning and transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, and nitrogen adsorption. The resulting material has a micro-fibrous mor- phology and is basically composed of metallic Fe^0 and FeO particles, i.e., more than 98 wt% of the carbon/ iron-based composite mass. These particles are held together by amorphous porous carbon foam obtained by in-situ carbonization of the polymer/Fe2O3 composite with evacuation of carbon from the system via COx gases released by carbo-reduction of Fe2O3. The material has significant activity in the reaction of catalytic decomposition of hydrogen peroxide in water solutions.

关键词： Composite materialsPorous carbonPolymersIron particles

Preface to the special Issue on Modeling and Data Analysis Methods for the sMILE mission

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Earth and Planetary Physics 2024年第1期8卷 1-4页

作者： TianRan sun Hyunju Connor andrey samsonov National space science Center Chinese Academy of SciencesBeijing 100190China NAsA Goddard space Flight Center US Mullard space science Laboratory University College LondonUK

The sMILE(solar wind Magnetosphere Ionosphere Link Explorer)project(http://***/smile/,https://***/web/smile/mission)is a joint spacecraft mission of the European space Agency(EsA)and the Chinese Academy of sciences(CAs)with an expected launch in *** aims to study the global interactions of solar wind–magnetosphere–ionosphere innovatively by imaging the Earth’s magnetosheath and cusps in soft X-rays and the northern auroral region in ultraviolet(UV)while simultaneously measuring plasma and magnetic field parameters in the solar wind and magnetosheath along a highly-elliptical and highly-inclined *** special issue is composed of 22 articles,presenting recent progress in modeling and data analysis techniques developed for the sMILE *** this preface,we categorize the articles into the following seven topics and provide brief summaries:(1)instrument descriptions of the soft X-ray Imager(sXI),(2)numerical modeling of the X-ray signals,(3)data processing of the X-ray images,(4)boundary tracing methods from the simulated images,(5)physical phenomena and a mission concept related to the scientific goals of sMILE-sXI,(6)studies of the aurora,and(7)ground-based support for sMILE.

关键词： sMILE X-ray imaging magnetosphere auroral ionosphere

Early Jurassic Climate Warming in Eastern siberia: First Macrofloristic Evidence from Irkutsk Basin, Russia

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Acta Geologica sinica(English Edition) 2024年第4期98卷 1035-1050页

作者： andrey FROLOV Irina MAsHCHUK Institute of the Earth's Crust Siberian Branch of the Russian Academy of SciencesIrkutsk664033Russia

Numerous new records of Ferganiella, Podozamites, and schidolepium, including a new species, Ferganiella ivantsovii sp. nov., are described from the Early Jurassic(Toarcian) Middle subformation of the Prisayan Formation from the Euro-sinian paleofloristic region in the Irkutsk Basin, Eastern siberia, Russia. An analysis of the paleogeographic distribution of Ferganiella and Podozamites shows that both genera were the most diverse and numerous in the East Asian province of the Euro-sinian region and in the Northern Chinese province of the siberian region during the Early and Middle Jurassic. These phytochoria were located in the subtropical and temperate subtropical climate zones, which allows us to consider Ferganiella and Podozamites as thermophilic plants, which are important indicators of the Early Toarcian climatic optimum. Their abundance in the Irkutsk Basin thus may indicate Early Toarcian warming;further abundant schidolepium cones, which produced Araucariacites pollen, typical for Euro-sinian flora complement the scenario. Thus, the new finds are the first macrofloristic indicators of the Toarcian climatic optimum in the Irkutsk Basin.

关键词： paleobotany Ferganiella Podozamites schidolepium Toarcian climatic optimum paleobiogeography siberian paleofloristic region Irkutsk

Irisin/BDNF signaling in the muscle-brain axis and circadian system: A review

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The Journal of Biomedical Research 2024年第1期38卷 1-16页

作者： Alexey N.Inyushkin Vitalii s.Poletaev Elena M.Inyushkina Igor s.Kalberdin andrey A.Inyushkin Department of Human&Animal Physiology Samara National Research UniversitySamara 443011Russia.

In mammals,the timing of physiological,biochemical and behavioral processes over a 24-h period is controlled by circadian *** entrain the master clock located in the suprachiasmatic nucleus of the hypothalamus to a precise 24-h rhythm,environmental zeitgebers are used by the circadian *** is done primarily by signals from the retina via the retinohypothalamic tract,but other cues like exercise,feeding,temperature,anxiety,and social events have also been shown to act as non-photic *** recently identified myokine irisin is proposed to serve as an entraining non-photic signal of *** is a product of cleavage and modification from its precursor membrane fibronectin typeⅢdomain-containing protein 5(FNDC5)in response to *** from well-known peripheral effects,such as inducing the"browning"of white adipocytes,irisin can penetrate the blood-brain barrier and display the effects on the *** data suggest that FNDC5/irisin mediates the positive effects of physical activity on brain *** several brain areas,irisin induces the production of brain-derived neurotrophic factor(BDNF).In the master clock,a significant role in gating photic stimuli in the retinohypothalamic synapse for BDNF is ***,the brain receptor for irisin remains *** the current review,the interactions of physical activity and the irisin/BDNF axis with the circadian system are reconceptualized.

关键词： irisin brain-derived neurotrophic factor peroxisome proliferator-activated receptorγcoactivator 1α circadian rhythm circadian system muscle-brain axis

simulation of the sMILE soft X-ray Imager response to a southward interplanetary magnetic field turning

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Earth and Planetary Physics 2024年第1期8卷 39-46页

作者： andrey samsonov Graziella Branduardi-Raymont steven sembay Andrew Read David sibeck Lutz Rastaetter Mullard space science Laboratory University College LondonDorking RH56NTUK Leicester University Leicester LE17RHUK Goddard space Flight Center National Aeronautics and Space AdministrationGreenbeltMD 20771USA

The solar wind Magnetosphere Ionosphere Link Explorer(sMILE)soft X-ray Imager(sXI)will shine a spotlight on magnetopause dynamics during magnetic *** simulate an event with a southward interplanetary magnetic field turning and produce sXI count maps with a 5-minute integration *** making assumptions about the magnetopause shape,we find the magnetopause standoff distance from the count maps and compare it with the one obtained directly from the magnetohydrodynamic(MHD)*** root mean square deviations between the reconstructed and MHD standoff distances do not exceed 0.2 RE(Earth radius)and the maximal difference equals 0.24 RE during the 25-minute interval around the southward turning.

关键词： magnetopause magnetic reconnection solar wind charge exchange southward interplanetary magnetic field numerical modeling solar wind Magnetosphere Ionosphere Link Explorer(sMILE) soft X-ray Imager

Impact of doping profiles on the formation of laser-active centers in bismuth-doped GeO_(2)–siO_(2)glass fibers

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Photonics Research 2024年第2期12卷 260-270页

作者： sERGEY ALYsHEV ALEXANDER VAKHRUsHEV ALEKsANDR KHEGAI ELENA FIRsTOVA KONsTANTIN RIUMKIN MIKHAIL MELKUMOV LYUDMILA IsKHAKOVA andrey UMNIKOV sERGEI FIRsTOV Prokhorov General Physics Institute of the Russian Academy of sciences Dianov Fiber Optics Research Center119333 MoscowRussia Devyatykh Institute of Chemistry of High-Purity substances of the Russian Academy of sciences 603951 Nizhny NovgorodRussia

Multi-wavelength-band transmission technology based on the exploitation of the extended spectral region is considered as a potential approach to increase the transmission capacity in the deployed fiber-optic communication *** development of optical amplifiers operating in the O-,E-,s-,and U-telecom bands is an extremely important challenge for the successful implementation of this ***-doped fibers are of increasing interest as gain materials,which can be used to provide broadband amplification in the mentioned telecom *** is due to the ability of Bi ions incorporated into glass network to form bismuth active centers(BACs)with specific optical properties,which are primarily determined by the glass *** this work,the impact of the doping profiles of both Ge atoms as glass modifiers and Bi ions on the BACs formation is studied using a series of bismuth-doped fibers fabricated by the modified chemical vapor deposition(MCVD)*** Bi-to-BACs conversion efficiency in various spatial regions of the studied samples is *** is turned out that for high-Bi concentration regions,the conversion efficiency is very low(less than 10%).In addition,the relationship of the conversion efficiency to the distribution of Bi ions and/or Ge atoms is ***,a continuous-wave laser at 1.46μm with a record slope efficiency of 80%is demonstrated using a Bi-doped fiber with confined doping profile,where the Bi-to-BACs conversion efficiency is 35%.This paper provides new information which might help to facilitate understanding of the features of Bi-doped fibers and their potentially achievable characteristics.

关键词： fiber fibers bismuth

Enhancing crystal integrity and structural rigidity of CsPbBr_(3) nanoplatelets to achieve a narrow colorsaturated blue emission

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Light(science & Applications) 2024年第5期13卷 985-997页

作者： Qianqian Huang Wenxu Yin Bo Gao Qingsen Zeng Dong Yao Hao Zhang Yinghe Zhao Weijia Zheng Jiaqi Zhang Xuyong Yang Xiaoyu Zhang andrey L.Rogach Key Laboratory of Automobile Materials MOE School of Materials Science&Engineeringand Jilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy MaterialsJilin UniversityChangchunChina. state Key Laboratory of supramolecular structure and Materials College of ChemistryJilin UniversityChangchunChina. state Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhanHubeiChina. Department of Chemistry University of VictoriaVictoriaBCCanada. Key Laboratory of Advanced Display and system Applications of Ministry of Education Shanghai UniversityShanghaiChina. Department of Materials science and Engineering and Centre for Functional Photonics(CFP)City University of Hong KongHong Kong S.A.RChina

Quantum-confined CsPbBr_(3) perovskites are promising blue emitters for ultra-high-definition displays,but their soft lattice caused by highly ionic nature has a limited ***,we endow CsPbBr_(3) nanoplatelets(NPLs)with atomic crystal-like structural rigidity through proper surface engineering,by using strongly bound N-dodecylbenzene sulfonic acid(DBsA).A stable,rigid crystal structure,as well as uniform,orderly-arranged surface of these NPLs is achieved by optimizing intermediate reaction stage,by switching from molecular clusters to mono-octahedra,while interaction with DBsA resulted in formation of a Cs_(x)O monolayer shell capping the NPL *** a result,both structural and optical stability of the CsPbBr3 NPLs is enhanced by strong covalent bonding of DBsA,which inhibits undesired phase transitions and decomposition of the perovskite phase potentially caused by ligand ***,rather small amount of DBsA ligands at the NPL surface results in a short inter-NPL spacing in their closely-packed films,which facilitates efficient charge injection and *** photoluminescence of the produced CsPbBr_(3) NPLs is bright(nearly unity emission quantum yield)and peaks at 457 nm with an extremely narrow bandwidth of 3.7 nm at 80 K,while the bandwidth of the electroluminescence(peaked at 460 nm)also reaches a record-narrow value of 15 nm at room *** value corresponds to the CIE coordinates of(0.141,0.062),which meets Rec.2020 standards for ultra-high-definition displays.

关键词： temperature stability narrow

Exploring van der Waals materials with high anisotropy:geometrical and optical approaches

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Light(science & Applications) 2024年第4期13卷 645-653页

作者： Aleksandr s.slavich Georgy A.Ermolaev Mikhail K.Tatmyshevskiy Adilet N.Toksumakov Olga G.Matveeva Dmitriy V.Grudinin Kirill V.Voronin Arslan Mazitov Konstantin V.Kravtsov Alexander V.syuy Dmitry M.Tsymbarenko Mikhail s.Mironov sergey M.Novikov Ivan Kruglov Davit A.Ghazaryan andrey A.Vyshnevyy Aleksey V.Arsenin Valentyn s.Volkov Kostya s.Novoselov Moscow Center for Advanced studies Kulakova str.20Moscow 123592Russia. Emerging Technologies Research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. Donostia International Physics Center(DIPC) Donostia/San-Sebastián 20018Spain. Institute of Materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. Laboratory of Advanced Functional Materials Yerevan State UniversityYerevan 0025Armenia. National Graphene Institute(NGI) University of ManchesterManchester M139PLUK. Department of Materials science and Engineering National University of SingaporeSingapore 03-09 EASingapore. Institute for Functional Intelligent Materials National University of Singapore117544 SingaporeSingapore

The emergence of van der Waals(vdW)materials resulted in the discovery of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless novel phenomena and *** success inspired an intensive search for the highest possible anisotropic properties among vdW ***,the identification of the most promising among the huge family of vdW materials is a challenging quest requiring innovative ***,we suggest an easy-to-use method for such a survey based on the crystallographic geometrical perspective of vdW materials followed by their optical *** our approach,we found As2s3 as a highly anisotropic vdW *** demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and over two times as large as calcite,high refractive index,and transparency in the visible range,overcoming the century-long record set by *** these benefits,As2s3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wave plate that combines classical and the Fabry–Pérot optical phase ***,our approach provides an effective and easy-to-use method to find vdW materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.W.Wi Y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil University

We investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence sensitizer Rare earths

First evidence for chiral wobbling of triaxial nuclei

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Nuclear science and Techniques 2024年第7期35卷 4-7页

作者： s.Frauendorf Department of Physics and Astronomy University of Notre DameNotre DameIN 46556USA

Chirality(Greek“handiness”)is a property of many com-plex *** molecules exist in two forms,one being the mirror image of the *** for our hands,it is impossible to make the images identical by a suitable *** two forms are called left-handed and *** have the same binding energy,because the electro-magnetic interaction,which holds the molecule together,does not change under a *** properties that are insensitive to the geometry are also the *** different geometry is the reason why the left-handed form turns the polarization plane of transmitted light in one direction by some angle while the right-handed form turns it in the oppo-site direction by the same ***,the geometrical differences between the two species may have other *** two species of the carvon molecule shown in Fig.1 taste quite differently.

关键词： turns Chiral mirror