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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

A staunch veteran Bolshevik——Celebrating the centennial of the Communist Party of China

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Voice of Friendship 2021年第3期 71-74页

作者： richard frey Jr. 不详

Last year marked the 100 th birthday of my late father,richard *** his 84-year lifetime,he was a member of the Communist Party of China for 60 years,apart from the years he held a membership of the Austrian Communist ... 详细信息

关键词： membership Communist lifetime

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

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

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.

Multiple forest structural elements are needed to promote beetle biomass, diversity and abundance

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Forest Ecosystems 2022年第5期9卷 585-595页

作者： Nolan J.Rappa Michael Staab Julian frey Nathalie Winiger Alexandra-Maria Klein Nature Conservation and Landscape Ecology University of FreiburgTennenbacherstrasse 479106Freiburg im BreisgauGermany Ecological Networks Technical University DarmstadtSchnittspahnstrasse 364287DarmstadtGermany Forest Growth and Dendroecology University of FreiburgTennenbacherstrasse 479106Freiburg im BreisgauGermany Wildlife Ecology and Management University of FreiburgTennenbacherstrasse 479106Freiburg im BreisgauGermany

Background:Retention forestry is a management strategy aiming to mitigate biodiversity loss by retaining structural elements such as dead trees that would otherwise be *** we analyze the biomass,diversity and abundance among forest beetles collected using window traps on 1281-ha forest sites reflecting gradients in the amount of structural elements in southwestern ***:We found that beetle biomass increased with mean diameter at breast height(a measure of tree size),and decreased with stand structural *** of individual feeding guilds responded differently to forest structural elements,namely lying deadwood,understory complexity,tree basal area and stand structural *** family diversity increased with the effective number of layers,i.e.1-m forest strata occupied by vegetation assessed via terrestrial laser *** of feeding guilds responded to only elevation and share of deciduous *** composition in terms of biomass was structured by forest elements similar to biomass of individual feeding guilds,with the addition of lying *** differed from community composition in terms of abundance of feeding guilds,which was structured by primarily standing deadwood volume and share of deciduous ***:Our results show that biomass,diversity and abundance respond differently to forest structural *** suggests that the concurrent prioritization of multiple forest elements is needed to promote forest beetles,with more focus placed on the differing resource needs among feeding *** addition,retention strategies should also consider the varying responses of beetle biodiversity metrics when assessing the importance of forest structural elements.

关键词： Allometry Biodiversity Coleoptera Forest management Terrestrial laser scanning Window trap

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

Anatomic relationship of extensor indicis propius and extensor digitorum communis: Implications for tendon transfer

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World Journal of Orthopedics 2022年第11期13卷 978-985页

作者： Joanne Zhou Christopher frey Nicole Segovia Jeffrey Yao Department of Orthopaedic Surgery Stanford University Medical CenterStanford UniversityRedwood cityCA 94063United States

BACKGROUND The extensor indicis proprius(EIP)tendon is a frequently used donor for a variety of tendon transfers,most commonly for reconstruction of the extensor pollicis longus(EPL).EIP is known to have frequent anatomic variants including split tendons and variations in tendon *** To characterize the anatomy of the EIP at the level of the extensor retinaculum,where tendon harvest is often performed,and share our preferred technique for EIP to EPL *** Twenty-nine fresh-frozen cadaveric forearms without history of forearm or hand injury or surgery were *** circumference and relationship of the EIP and extensor digitorum communis to the index(EDCI)at the metacarpophalangeal(MCP)joint and the distal extensor retinaculum were *** from the distal extensor retinaculum to the EIP myotendinous junction was *** EIP was ulnar to the EDCI in 96.5%of specimens(28/29)at the distal edge of the extensor *** the remaining specimen,EIP was volar to *** circumference at the distal extensor retinaculum averaged(9.3 mm±1.7 mm)for EDCI and 11.1 mm(±2.7 mm)for EIP(P=0.0010).The tendon circumference at the index MCP joint averaged 11.0 mm(±1.7 mm)for EDCI and 10.6 mm(±2.1 mm)for EIP(P=0.33).EIP had a greater circumference in 76%(22/29)of specimens at the distal extensor retinaculum whereas EIP had a greater circumference in only 31%(9/29)of specimens at the MCP *** The EIP tendon is frequently ulnar to and greater in circumference than the EDCI at the distal extensor retinaculum,which can be taken into consideration for tendon transfers involving EIP.

关键词： Surgical anatomy Tendon transfer Extensor digitorum communis Extensor indicis proprius Tendon harvest Cadaveric Dissection

东南沿海地区古近纪大陆岩石圈地幔特征及成因

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地学前缘 2003年第3期10卷 77-85页

作者：赵海玲 Fred a.frey HANG Shichun 于俊吉邓晋福刘振文李凯明狄永军赵国泉刘清华岩石圈构造深部过程及探测技术教育部重点实验室北京100083 中国地质大学地球科学与资源学院北京100083 美国麻省理工学院美国马萨诸塞州坎布里奇MA02139

东南沿海地区新生代玄武岩中的橄榄岩包体来自岩石圈地幔 ,上地幔橄榄岩包体的岩石学及地球化学特征都记录了地幔演化的历史。普宁橄榄岩包体斜方辉石含量与太古宙克拉通地幔类似 ,但在矿物学、REE、痕量元素和Sr Nd同位素上又与太古宙... 详细信息

东南沿海地区新生代玄武岩中的橄榄岩包体来自岩石圈地幔 ,上地幔橄榄岩包体的岩石学及地球化学特征都记录了地幔演化的历史。普宁橄榄岩包体斜方辉石含量与太古宙克拉通地幔类似 ,但在矿物学、REE、痕量元素和Sr Nd同位素上又与太古宙岩石圈地幔不同。橄榄岩包体的岩相学、矿物学、REE、痕量元素特征都提供了含H2 O富Si流体交代橄榄岩的证据 ,这种流体可能主要是洋壳物质局部熔融而成。流体交代使橄榄岩富Si,同时富Sr、Pb和强不相容元素等大洋岩石圈物质。这表明普宁大陆岩石圈地幔既保留太古宙岩石圈地幔的特征 ,又具有大洋俯冲地幔的特征 ,它是古老岩石圈地幔向大洋岩石圈地幔转换的一部分 ,这种转换可能是大洋岩石圈与大陆岩石圈地幔相互作用的结果。

关键词：东南沿海地区俯冲作用大陆岩石圈地幔地幔橄榄岩流体