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Repeated kimberlite magmatism beneath Yakutia and its relationship to Siberian flood volcanism:insights from in situ U–Pb and Sr–Nd perovskite isotope analysis

Repeated kimberlite magmatism beneath Yakutia and its relati...

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中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Jing Sun Chuan-Zhou Liu Sebastian Tappe sergey i.kostrovitsky Fu-Yuan Wu Dmitry Yakovlev Yue-Heng Yang Jin-Hui Yang State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences De Beers Group Exploration School of Geosciences University of the Witwatersrand institute of Geochemistry Siberian Branch of the Russian Academy of Sciences

We report combined U–Pb ages and Sr–Nd isotope compositions of perovskites from 50 kimberlite occurrences,sampled from 9 fields across the Yakutian kimberlite province on the Siberian *** new U–Pb ages,together with previously reported geochronological constraints,suggest that kimberlite magmas formed repeatedly during at least 4 episodes:Late Silurian–Early Devonian(419–410 Ma),Late Devonian–Early Carboniferous(376–347 Ma),Late Triassic(231–215 Ma),and Middle/Late Jurassic(171–156 Ma).Recurrent kimberlite melt production beneath the Siberian craton–before and after flood basalt volcanism at 250 Ma–provides a unique opportunity to test existing models for the origin of global kimberlite *** internally consistent Sr and Nd isotope dataset for perovskites reveals that the Paleozoic and Mesozoic kimberlites of Yakutia have distinctly different initial radiogenic isotope *** exists a notable increase in the initial 143Nd/144Nd ratios through time,with an apparent isotopic evolution that is intermediate between that of Bulk Earth and Depleted MORB *** the Paleozoic samples range between initial 87Sr/86Sr of 0.7028–0.7034 and 143Nd/144Nd of 0.51229–0.51241,the Mesozoic samples show values between 0.7032–0.7038 and 0.51245–0.51271,***,perovskites from all studied Yakutian kimberlite fields and age groups have moderately depleted initialεNd values that fall within a relatively narrow range between+1.8 and+*** perovskite isotope systematics of the Yakutian kimberlites are interpreted to reflect magma derivation from the convecting upper mantle,which appears to have a record of continuous melt depletion and crustal recycling throughout the *** analyzed perovskites neither record highly depleted nor highly enriched isotopic components,which had been previously identified in likely plume-related Siberian Trap *** Siberian craton has frequently been suggested to represent a type example of an a

关键词： perovskite recurrent kimberlite magmatism Siberian craton large igneous provinces(LiPs) SiMS

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Arctic sea-ice extent: No record minimum in 2023 or recent years

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola M.Johannessen Tor i.Olaussen Nansen Scientific Society BergenNorway Nansen Environmental and Remote Sensing Center BergenNorway

Arctic sea-ice extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. in general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic Minimum ice Climate

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Coarse to Fine: The Role of Severe Plastic Deformation in Advancing Titanium-Based Medical implants - A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 295-306页

作者： Dragana R Mihajlović Bojan i Međo ivana Lj Cvijović-Alagić Veljko R Djokić Faculty of Technology and Metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Vinča institute of Nuclear Sci-ences-National institute of the Republic of Serbia University of Belgrade11001BeogradSerbia innovation Centre of the Faculty of Technology and Metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic deformation(SPD)procedures,which are utilized to form an ultrafine-grained structure in metallic *** the SPD process,a solid material sample is subjected to very high loads without a significant change in sample *** the present work,the high-pressure torsion(HPT)process,as one of the SPD techniques,which achieves a high degree of deformation and ensures refinement of the microstructure,will be discussed in more *** that grain size control is accepted as a method to obtain materials with desired characteristics,an overview of the properties of ultrafine-grained titanium-based biomaterials to be used in medicine is ***,particular attention is dedicated to the influences of HPT process parameters,primarily hydrostatic pressure,and number of revolutions during torsion,on the grain size and physical and mechanical characteristics(modulus of elasticity,microhardness,and tensile properties),corrosion resistance,and biocompatibility of the titanium-based biomaterials.A review of the literature indicates that titanium-based materials obtained by the SPD process show improved mechanical and physical properties without losing biocompatibility and corrosion resistance,which suggests that these methods of obtaining implants are something that should be further developed in the future.

关键词： high-pressure torsion process ultrafine-grained titanium-based materials electrochemical anodization physical properties mechanical properties

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Bifunctional gap-plasmon metasurfaces for visible light: polarization-controlled unidirectional surface plasmon excitation and beam steering at normal incidence

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Light(Science & Applications) 2017年第1期6卷 7-14页

作者： Fei Ding Rucha Deshpande sergey i Bozhevolnyi SDU Nano Optics University of Southern DenmarkCampusvej 55Odense DK-5230Denmark

integration of multiple diversified functionalities into a single,planar and ultra-compact device has become an emerging research area with fascinating possibilities for realization of very dense integration and miniaturization in photonics that requires addressing formidable challenges,particularly for operation in the visible *** we design,fabricate and experimentally demonstrate bifunctional gap-plasmon metasurfaces for visible light,allowing for simultaneous polarization-controlled unidirectional surface plasmon polariton(SPP)excitation and beam steering at normal *** designed bifunctional metasurfaces,consisting of anisotropic gap-plasmon resonator arrays,produce two different linear phase gradients along the same direction for respective linear polarizations of incident light,resulting in distinctly different functionalities realized by the same *** proof-of-concept fabricated metasurfaces exhibit efficient(425%on average)unidirectional(extinction ratio 420 dB)SPP excitation within the wavelength range of 600–650 nm when illuminated with normally incident light polarized in the direction of the phase *** the same time,broadband(580–700 nm)beam steering(30.6°–37.9°)is realized when normally incident light is polarized perpendicularly to the phase gradient *** bifunctional metasurfaces developed in this study can enable advanced research and applications related to other distinct functionalities for photonics integration.

关键词： beam steering bifunctional gap-plasmon metasurfaces surface plasmon polaritons

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Flash Lamps as ignition and initiation Sources of the VS-2 Pyrotechnic Composition

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含能材料 2022年第4期30卷 370-378页

作者： sergey i.Gerasimov Mikhail A.ilyushin sergey M.Putis sergey A.Dushenok irina V.Shugalei Andrey M.Sudarikov Russian Federal Nuclear Center‑All‑Russian Research institute of Experimental Physics SarovRussia Sarov institute of Physics and Technology is a Branch of the Scientific Research Nuclear University MEPhi SarovRussia Nizhny Novgorod State Technical University Named after R.E.Alekseev Nizhny NovgorodRussia RAS institute for Studying Problems in Mechanical Engineering ‑is a Branch of the RAS Applied Physics InstituteNizhny NovgorodRussia "Technologist"Special Design and Technological Bureau St.PetersburgRussia Saint‑Petersburg State institute of Technology(Technical University) St.PetersburgRussia Russian State Hydro‑meteorological University St.PetersburgRussia

in the present work it is found that the pyrotechnic composition VS⁃2 can be initiated with flash lamps iFC⁃500 and ***⁃2 pyrotechnic composition contains 90%of mercury(Ⅱ)5⁃hydrazinotetrazolate perchlorate and 10%of optically trans⁃parent copolymer of 2⁃methyl⁃5⁃vinyltetrazole and methacrylic acid(PVMT).We have found that the flash lamps make it possi⁃ble to initiate combustion of VS⁃2 composition with its transition to detonation both in cylindrical charges placed in brass caps of 5 mm diameter and 2 mm high,and film charges with 10 mm×80 mm in size and surface weights of 60 mg·cm^(-2)and 90 mg·cm^(-2),showing ignition delay times 10μs and 3μs,*** also measured detonation velocities for VS⁃2 composition film charges,which were 4375-4505 m·s^(-1)(of the charge being surface mass 60 mg·cm^(-2))and 4221-4281 m·s^(-1)(of the charge be⁃ing surface mass 90 mg·cm^(-2))and their blasting action on the aluminum *** depths of the normal shock wave imprints at the charge⁃barrier interface were 0.6-0.7 mm(for surface mass of the film charges 60 mg·cm^(-2))and 1.2-1.3 mm(for surface mass of the film charges 90 mg·cm^(-2))

关键词： VS⁃2 pyrotechnic composition flash lamps ignition transition of combustion to detonation blasting action

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Multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review

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Neural Regeneration Research 2025年第1期20卷 82-92页

作者： Stiven Roytman Rebecca Paalanen Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico i.Bohnen Department of Radiology University of MichiganAnn ArborMIUSA Department of Neurology University of MichiganAnn ArborMIUSA Morris K.Udall Center of Excellence for Parkinson’s Disease Research University of MichiganAnn ArborMIUSA institute for Kinesiology Research Science and Research Centre KoperKoperSlovenia Department of Health Sciences Alma Mater Europaea–ECMMariborSlovenia Parkinson’s Foundation Research Center of Excellence University of MichiganAnn ArborMIUSA Department of Neurology University of GroningenUniversity Medical Center GroningenGroningenThe Netherlands Neurology Service and GRECC VA Ann Arbor Healthcare SystemAnn ArborMIUSA

Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging *** and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous *** effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory *** mechanisms which underpin the integration of these multisensory signals are the principal topic of the present *** multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older *** emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and *** the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s *** also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older ***,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases.

关键词： aging balance encephalography functional magnetic resonance imaging gait multisensory integration Parkinson’s disease positron emission tomography somatosensory vestibular visual

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BER Performance of Finite in Time Optimal FTN Signals for the Viterbi Algorithm

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Journal of Electronic Science and Technology 2020年第1期18卷 42-51页

作者： sergey B.Makarov ilya i.Lavrenyuk Anna S.Ovsyannikova sergey V.Zavjalov Higher School of Applied Physics and Space Technologies Peter the Great St.Petersburg Polytechnic UniversitySt.Petersburg 195251

in this article, we consider the faster than Nyquist(FTN) technology in aspects of the application of the Viterbi algorithm(VA). Finite in time optimal FTN signals are used to provide a symbol rate higher than the "Nyquist barrier" without any encoding. These signals are obtained as the solutions of the corresponding optimization problem. Optimal signals are characterized by intersymbol interference(iSi). This fact leads to significant bit error rate(BER) performance degradation for "classical" forms of signals. However, iSi can be controlled by the restriction of the optimization problem. So we can use optimal signals in conditions of increased duration and an increased symbol rate without significant energy losses. The additional symbol rate increase leads to the increase of the reception algorithm complexity. We consider the application of VA for optimal FTN signals reception. The application of VA for receiving optimal FTN signals with increased duration provides close to the potential performance of BER,while the symbol rate is twice above the Nyquist limit.

关键词： Bit error rate(BER)performance faster than Nyquist(FTN) Nyquist limit optimal signals Viterbi algorithm(VA)

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A review of ferroelectric materials for high power devices

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Journal of Materiomics 2022年第4期8卷 739-752页

作者： sergey i.Shkuratov Christopher S.Lynch Loki incorporated 1334 Royal RoadNorwoodMO65717USA Bourns College of Engineering University of California at RiversideCA92521USA

Compact autonomous ultrahigh power density energy storage and power generation devices that exploitthe spontaneous polarization of ferroelectric materials are capable of producing hundreds of kilovoltvoltages,multi-kiloampere currents,and megawatt power levels for brief interval of *** storagelife of these devices is four orders of magnitude longer than that for electrochemical batteries andelectrochemical *** is an up to date survey of ferroelectric materials used for these highpower *** types of ferroelectric ceramics possess the ability to be depolarized under adia-batic compression and can be successfully used for high power *** addition to bulk ferro-electric ceramics,multilayer ferroelectric films are very efficient materials for high power *** importance is the ability of relaxor ferroelectric single crystals to produce significantly higherelectric charge density and energy density than ceramics,making them promising materials for highpower *** provided is a brief survey of recent developments of ferroelectric materials forhigh energy density and power density dielectric *** ceramics have been developed,including antiferroelectric and relaxor antiferroelectric solid solutions,providing high energy densityand efficiency simultaneously.

关键词： Energy storage Ferroelectric Antiferroelectric Relaxor High power density

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Apolipoprotein A-i binding protein-mediated neuroprotection in glaucomatous neuroinflammation and neurodegeneration

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Neural Regeneration Research 2025年第5期20卷 1414-1415页

作者： Sinwoo Hwang Seunghwan Choi Soo-Ho Choi Keun-Young Kim Yury i.Miller Won-Kyu Ju Hamilton Glaucoma Center and Shiley Eye institute The Viterbi Family Department of OphthalmologyUniversity of California San DiegoLa JollaCAUSA Department of Medicine University of California San DiegoLa JollaCAUSA National Center for Microscopy and imaging Research Department of NeurosciencesUniversity of California San DiegoLa JollaCAUSA

Glaucoma is a multifactorial eye disorder that can cause vision loss and irreversible blindness,affecting individ uals aged 40 to 80 yea rs *** to the aging population,it is expected that the number of people affected by glaucoma will surpass 111 million by 2040 as the disease becomes more *** primarily contributes to optic nerve axon loss and the progressive degeneration of retinal ganglion cells (RGCs),subsequently leading to vision impairment.

关键词： irreversible pass primarily

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Single and multi domain buckled germanene phases on Al(111)surface

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Nano Research 2019年第12期12卷 2988-2996页

作者： Dmitriy A.Muzychenko sergey i.Oreshkin Vladimir i.Panov Chris Van Haesendonck Andrey i.Oreshkin Faculty of Physics Lomonosov Moscow State University119991 MoscowRussia Sternberg Astronomical institute Lomonosov Moscow State University119234 MoscowRussia Solid-State Physics and Magnetism Section KU LeuvenBE-3001 LeuvenBelgium

The simultaneous formati on of single domain(3×3)and multi domai n(√7×√7)R(±19.1°)germa nene phases on Al(111)surface in thesub-monolayer range was studied using seanning tunneling microscopy(STM)and density functional theory(DFT)based *** results revealed that both germa nene phases nu cleate and grow in dependently from each other and regardless of Al substratetemperature within significantly expanded range Ts=27-200℃.Our results unambiguously showed that STM images with hexagonalcontrast yield correct-resolved structure for both germanene phases,while honeycomb contrast is a result of an artificial tip-induced STM ***-principles calculations suggested atomic models with strongly buckled germanene(2×2)/Al(111)(3×3)and(√3×√3)R30°/Al(111)(√7×√7)R(±19.1°)with one of eight and one of six Ge atoms protruding upward respectively,that consistently describe the experimentally observed STM images both for single and multi domai n surface *** to the DFT based simulati ons both germa nene(2×2)and(√3×√3)R30°superstructures have a stretched lattice strain with respect to the ideal free-standing germa nene by 6.2%and 13.9%,***,numerous small domains separated by domain boundaries in the(√3×√3)R30°/Al(111)(√7×√7)R(±19.1°)germanenephase tend to reduce the surface energy and prevent the formation of extended single domains,in contrast to the(2×2)/Al(111)(3×3)***,our experimental results showed that the nucleation and growth of germa nene on Al(111)surface yield strong modifications of Alsurface even at room temperature(RT),which may be contributed to the formation of Al-Ge alloy due to Ge surface solid-states reactivitythat was ignored in recent *** is already evident from our present findings that the role of Al atoms in the formation of(3×3)and(√7×√7)R(±19.1°)germa nene phases is worthy to be carefully studied in the future,which could be an important knowledge for large-quantityfabrication of germane

关键词： germanene two-dimensional(2D)materials scanning tunneling microscopy density functional theory aluminum

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