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Fast jet proper motion discovered in a blazar at z=4.72

science Bulletin 2020年第7期65卷 525-530,M0003页

作者： Yingkang Zhang Tao An sándor frey shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of sciences Beijing 100049China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China Konkoly Observatory Research Centre for Astronomy and Earth SciencesKonkoly Thege Miklósút 15-17H-1121 BudapestHungary

High-resolution observations of high-redshift(z > 4) radio quasars offer a unique insight into jet kinematics at early cosmological epochs, as well as constraints on cosmological model *** to the general weakness of extremely distant objects and the apparently slow structural changes caused by cosmological time dilation, only a couple of high-redshift quasars(HRQs) have been studied with parsec-scale resolutions, and with limited number of observing epochs. Here we report on very long baseline interferometry(VLBI) observations of a high-redshift blazar J1430 + 4204(z=4.72) in the 8 GHz frequency band at five different epochs spanning 22 years. The source shows a compact core–jet structure with two jet components being identified within 3 milli-arcsecond(mas) scale. The long time span and multiple-epoch data allow for the kinematic studies of the jet components. That results in a jet proper motion of μ(J1) = 0.017 ± 0.002 mas a^-1 and μ(J2) = 0.156 ± 0.015 mas a^-1, respectively. For the fastest-moving outer jet component J2, the corresponding apparent transverse speed is (19.5 ± 1.9) *** inferred bulk jet Lorentz factor C=14.6 ± 3.8 and viewing angle θ=2.2°± 1.6°indicate highly relativistic beaming. The Lorentz factor and apparent proper motion are the highest measured to date among the z > 4 jetted radio sources, while the jet kinematics is still consistent with the cosmological interpretation of quasar redshifts.

关键词： Nuclei High-redshift Radio continuum Quasars Individual J1430+4204

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Improved Quantile Convolutional and Recurrent Neural Networks for Electric Vehicle Battery Temperature Prediction

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Big Data Mining and Analytics 2024年第2期7卷 512-530页

作者： Andreas M.Billert Runyao Yu stefan Erschen Michael frey Frank Gauterin Karlsruhe Institute of Technology(KIT) Institute of Vehicle System TechnologyKarlsruhe 76131Germanyand also with Bayerische Motoren Werke(BMW)AGMunich 80788Germany Technical University of Munich(TUM) Munich 80333Germany BMW AG Munich 80788Germany KIT Institute of Vehicle System TechnologyKarlsruhe 76131Germany

The battery thermal management of electric vehicles can be improved using neural networks predicting quantile sequences of the battery *** work extends a method for the development of Quantile Convolutional and Quantile Recurrent Neural Networks(namely Q*NN).Fleet data of 225629 drives are clustered and balanced,simulation data from 971 simulations are augmented before they are combined for training and *** Q*NN hyperparameters are optimized using an efficient Bayesian optimization,before the Q*NN models are compared with regression and quantile regression models for four *** analysis of point-forecast and quantile-related metrics shows the superior performance of the novel Q*NN *** median predictions of the best performing model achieve an average RMsE of 0.66°C and R^(2) of *** predicted 0.99 quantile covers 98.87%of the true values in the test *** conclusion,this work proposes an extended development and comparison of Q*NN models for accurate battery temperature prediction.

关键词： deep learning battery temperature convolutional and recurrent neural network quantile forecasting

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Recycled graphite for more sustainable lithium-ion batteries

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Carbon Energy 2024年第5期6卷 15-24页

作者： Mayokun Olutogun Anna Vanderbruggen Christoph frey Martin Rudolph Dominic Bresser stefano Passerini Helmholtz Institute Ulm(HIU) Ulm Germany Karlsruhe Institute of Technology(KIT) KarlsruheGermany Helmholtz Zentrum Dresden-Rossendorf(HZDR) Helmholtz Institute Freiberg for Resource Technology(HIF)FreibergGermany ProGraphite GmbH UntergriesbachGermany Chemistry Department Sapienza University of RomeRomeItaly

The demand for lithium-ion batteries(LIBs)is driven largely by their use in electric vehicles,which is projected to increase dramatically in the *** great success,however,urgently calls for the efficient recycling of LIBs at the end of their ***,we describe a froth flotation-based process to recycle graphite—the predominant active material for the negative electrode—from spent LIBs and investigate its reuse in newly assembled *** has been found that the structure and morphology of the recycled graphite are essentially unchanged compared to pristine commercial anode-grade graphite,and despite some minor impurities from the recycling process,the recycled graphite provides a remarkable reversible specific capacity of more than 350 mAh g^(−1).Even more importantly,newly assembled graphite‖NMC532 cells show excellent cycling stability with a capacity retention of 80%after 1000 cycles,that is,comparable to the performance of reference full cells comprising pristine commercial graphite.

关键词： anode graphite lithium-ion battery recycling sustainability

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Design of Geodetic sVLBI satellite Orbit and Its Tracking Network

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Geo-spatial Information science 2008年第1期11卷 6-12页

作者： WEI Erhu LIU Jingnan KULKARNI M.N. frey sándor school of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China the Key Laboratory of Geospace Environment and Geodesy Ministry of Education Wuhan University 129 Luoyu Road Wuhan 430079 China 不详

sVLBI （space very long baseline interferometry） has some important potential applications in geodesy and geodynamics, for which one of the most difficult tasks is to precisely determine the orbit of an sVLBI satellite. This work studies several technologies that will possibly be able to determine the orbit of a space VLBI satellite. Then, according to the types and charac- teristics of the satellite and the requirements for geodetic study and the geometry of the GNss （GPs, GALILEO） satellite to track the space VLBI satellite, the six Keplerian elements of the sVLBI satellite （TEsT-sVLBI） are determined. A program is designed to analyze the coverage area of space of different altitudes by the stations of the network, with which the tracking network of TEsT-sVLBI is designed. The efficiency of tracking TEsT-sVLBI by the network is studied, and the results are presented.

关键词： sVLBI precise orbit determination orbit design tracking network

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Nickela-electrocatalyzed sulfide and phosphine oxygenations with water

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science China Chemistry 2021年第6期64卷 873-874页

作者： Long Yang Johanna frey Lutz Ackermann Institut für Organische und Biomolekulare Chemie Georg-August-Universität GöttingenTammannstrasse 2Göttingen 37077Germany Wöhler Research Institute for sustainable Chemistry(WIsCh) Georg-August-Universität GöttingenTammannstrasse 2Göttingen 37077Germany

Molecular electrochemistry has emerged as an environmentally-friendly *** major recent momentum was gained in electrocatalyzed bond activations by earth-abundant 3 d transition metals[1],cost-effective nickela-electrocatalysis continuous to be underdevelopment for electrocatalysis[2].Nickel is an essential component of metalloproteins involved in catalytic aerobic oxygenation processes,for which nickel-dioxygen species were proposed as the key catalytic species[3].

关键词： catalyzed nickel Nickel

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Cherishing the Memory of My Father——In Commemoration of 10th Anniversary of Death of Richard frey

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Voice of Friendship 2014年第4期 49-52页

作者： Richard frey

November 16,2014 marked the10th anniversary of the passing of my father Richard *** that time,when sorting out books,writings and other materials left by him,I came to know more of family history and many parts of his life previously unfamiliar to *** has made me miss him all the *** father was born into a welloff middle-class Jewish family

关键词： father sorting Death anniversary marked shanxi Tia

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Prediction-based load balancing and resolution tuning for interactive volume raycasting

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Visual Informatics 2017年第2期1卷 106-117页

作者： Valentin Bruder steffen frey Thomas Ertl University of stuttgart Germany

We present an integrated approach for real-time performance prediction of volume raycasting that we employ for load balancing and sampling resolution *** volume rendering,the usage of acceleration techniques such as empty space skipping and early ray termination,among others,can cause significant variations in rendering performance when users adjust the camera configuration or transfer *** variations in rendering times may result in unpleasant effects such as jerky motions or abruptly reduced responsiveness during interactive *** avoid those effects,we propose an integrated approach to adapt rendering parameters according to performance *** assess performancerelevant data on-the-fly,for which we propose a novel technique to estimate the impact of early ray *** the basis of this data,we introduce a hybrid model,to achieve accurate predictions with minimal computational *** hybrid model incorporates aspects from analytical performance modeling and machine learning,with the goal to combine their respective *** show the applicability of our prediction model for two different use cases:(1)to dynamically steer the sampling density in object and/or image space and(2)to dynamically distribute the workload among several different parallel computing *** approach allows to reliably meet performance requirements such as a user-defined frame rate,even in the case of sudden large changes to the transfer function or the camera orientation.

关键词： Volume raycasting Performance prediction Load balancing

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Monomer-activated Copolymerization of Ethylene Oxide and Epichlorohydrin: In situ Kinetics Evidences Tapered Block Copolymer Formation

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Chinese Journal of Polymer science 2019年第9期37卷 912-918页

作者： Ann-Kathrin Danner Daniel Leibig Lea-Marie Vogt Holger frey Institute of Organic Chemistry Johannes Gutenberg- Universitat Mainz Duesbergweg 10-14 55128 Mainz Germany Graduate school Materials science in Mainz Staudinger Weg 9 55128 Mainz Germany

The monomer-activated anionic ring-opening copolymerization (AROP) of ethylene oxide (EO) and epichlorohydrin (ECH) using tetraoctylammonium bromide as an initiator and triisobutylaluminum (i-Bu3Al) as an activator was studied. The properties of the copolymers as well as the microstructure have been analyzed in detail via an in situ NMR kinetics study. The statistical copolymers exhibited molecular weights ranging from 2350 g·mol^-1 to 38000 g·mol^-1 (measured by sEC, PEG-standards) and moderate dispersities of 1.27-1.44. The thermal property tests revealed both a glass transition and melting for all copolymers, supporting a block-like nature. Applying in situ NMR kinetic measurements, the reactivity ratios of EO and ECH were determined to be strongly disparate, i.e., rEo = 9.2 and rECH = 0.10. This shows that the simple one-pot statistical anionic copolymerization of EO and ECH via the monomer-activated AROP resulted in the formation of strongly tapered, block-like structures. Furthermore, post-polymerization functionalization of the reactive chloromethyl groups by nucleophilic displacement was investigated for the copolymers. Copolymerization of EO and ECH offers a broad platform for further functionalization and therefore the possibility to prepare a variety of multifunctional PEGs.

关键词： Epichlorohydrin Polymerization Ring-opening Copolymerization Reactivity ratios Epoxide

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Cherishing the Memory of My Father——In Commemoration of 10th Anniversary of Death of Richard frey

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Voice of Friendship 2015年第1期 46-48页

作者： Richard frey Jr.

(Continued from the previous issue)My father,asa Chinesere volutionary of Austri and ecent,wasself-disciplined and low-key all his *** a 65-year revolutionary career in China—his second homeland—he witnessed the War of Resistance Against Japanese Aggression,War of Liberation,New China’s construction and development,the"cultural revolution"and reform and opening up;he underwent all kinds of hardships and suffered from *** unfairly treated and

关键词： revolution witnessed suffered father career Japane

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Adjustment of Forest Ecosystem Root Respiration as Temperature Warms

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Journal of Integrative Plant Biology 2008年第11期50卷 1467-1483页

作者： Andrew J.Burton Jerry M.Melillo serita D.frey Ecosystem science Center Michigan Technological University school of Forest Resources and Environmental science Michigan Technological University The Ecosystems Center Marine Biological Laboratory Department of Natural Resources University of New Hampshire

Adjustment of ecosystem root respiration to warmer climatic conditions can alter the autotrophic portion of soil respiration and influence the amount of carbon available for biomass production. We examined 44 published values of annual forest root respiration and found an increase in ecosystem root respiration with increasing mean annual temperature （MAT）, but the rate of this cross-ecosystem increase （Q10 = 1.6） is less than published values for short-term responses of root respiration to temperature within ecosystems （Q10 = 2-3）. When specific root respiration rates and root biomass values were examined, there was a clear trend for decreasing root metabolic capacity （respiration rate at a standard temperature） with increasing MAT. There also were tradeoffs between root metabolic capacity and root system biomass, such that there were no instances of high growing season respiration rates and high root biomass occurring together. We also examined specific root respiration rates at three soil warming experiments at Harvard Forest, UsA, and found decreases in metabolic capacity for roots from the heated plots. This decline could be due to either physiological acclimation or to the effects of co-occurring drier soils on the measurement date. Regardless of the cause, these findings clearly suggest that modeling efforts that allow root respiration to increase exponentially with temperature, with Q10 values of 2 or more, may over-predict root contributions to ecosystem CO2 efflux for future climates and underestimate the amount of C available for other uses, including net primary productivity.

关键词： acclimation climatic warming root biomass root respiration soil warming.

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