检索结果-南通市图书馆

同方期刊数据库

Copper-catalyzed C–H bond functionalization enabled by programmed alternating current

在线全文

学校读者我要写书评

暂无评论

science China Chemistry 2025年第1期68卷 10-11页

作者： Zhoumei Tan Kun Xu Chengchu Zeng Beijing Key Laboratory of Environmental and Viral Oncology College of Chemistry and Life Science Beijing University of Technology

Synthetic electrochemistry has been selected as one of the Top Ten Emerging Technologies in Chemistry in 2023 by International Union of Pure and Applied Chemistry (IUPAC)[1]. It has emerged as a sustainable platform for organic synthesis and has exhibited a wide range of applications from academia to industry [2]. However, electrosynthesis has been predominantly performed by using direct current (DC).

关键词：

Electrocatalytic nitrite reduction to ammonia on isolated bismuth alloyed ruthenium

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 369-376页

作者： Shiyao Shang Fuzhou Wang Zeyi Sun Chaofan Qiang Ke Chu School of Materials science and Engineering Lanzhou Jiaotong University

Electrochemical reduction of NO2-to NH3（NO2-RR） is recognized as an appealing approach for achieving renewable NH3synthesis and waste ***,we report isolated Bi alloyed Ru （Bi1Ru） as an efficient NO2-RR *** calculations and in situ electrochemical measurements reveal the creation of Bi1-Ru dual sites which can remarkably promote NO2-activation and suppress proton adsorption,while accelerating the NO2-RR protonation energetics to render a high NO2--to-NH3conversion ***,Bi1Ru assembled in a flow cell delivers an NH3yield rate of 1901.4μmol h-1cm-2and an NH3-Faradaic efficiency of 94.3%at an industrial-level current density of 324.3 mA *** study offers new perspectives for designing and constructing p-block single-atom alloys as robust and high-current-density NO2-RR catalysts toward the ammonia electrosynthesis.

关键词： Ammonia

High affinity soluble ILT2 receptor:a potent inhibitor of CD8^(+)T cell activation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Protein & Cell 2010年第12期1卷 1118-1127页

作者： Ruth K.Moysey Yi Li Samantha J.Paston Emma E.Baston Malkit S.Sami Brian J.Cameron Jessie Gavarret Penio Todorov Annelise Vuidepot Steven M.Dunn Nicholas J.Pumphrey Katherine J.Adams Fang Yuan Rebecca E.Dennis Deborah H.Sutton Andy D.Johnson Joanna E.Brewer Rebecca Ashfield Nikolai M.Lissin Bent K.Jakobsen Immunocore Limited 57c Milton ParkAbingdonOxonOX144RXUK current address:Oxford Nanopore Technologies UK current address:Geneva Merck Serono S.A. Switzerland current address:Adaptimmune Limited UK

Using directed mutagenesis and phage display on a soluble fragment of the human immunoglobulin superfamily receptor ILT2(synonyms:LIR1,MIR7,CD85j),we have selected a range of mutants with binding affinities enhanced by up to 168,000-fold towards the conserved region of major histocompatibility complex(MHC)class I *** in a dimeric form,either by chemical cross-linking with bivalent polyethylene glycol(PEG)derivatives or as a genetic fusion with human IgG Fc-fragment,the mutants exhibited a further increase in ligand-binding strength due to the avidity effect,with resident half-times(t1/2)on the surface of MHC I-positive cells of many *** novel compounds antagonized the interaction of CD8 co-receptor with MHC I in vitro without affecting the peptide-specific binding of T-cell receptors(TCRs).In both cytokine-release assays and cell-killing experiments the engineered receptors inhibited the activation of CD8^(+)cytotoxic T lymphocytes(CTLs)in the presence of their target cells,with subnanomolar potency and in a dose-dependent *** a selective inhibitor of CD8^(+)CTL responses,the engineered high affinity ILT2 receptor presents a new tool for studying the activation mechanism of different subsets of CTLs and could have potential for the development of novel autoimmunity therapies.

关键词： CD8^(+)T cells cellular activation autoimmunity cell surface molecules binding affinity phage display

维普期刊数据库

Economic effect of China's carbon neutrality target under shared socioeconomic pathways

在线全文

学校读者我要写书评

暂无评论

science China Earth sciences 2025年第1期68卷 142-157页

作者： Zemiao LIU Xianjin HUANG Xinxian QI School of Geography and Ocean science Nanjing University Key Laboratory of Carbon Neutrality and Territory Optimization Ministry of Natural Resources Frontiers science Center for Critical Earth Material Cycling Nanjing University

Economic feasibility is crucial for achieving the carbon neutrality target. However, current integrated assessments often underestimate the economic impacts of mitigation policies due to the lack of consideration of their economic benefits. This study integrates a warming-labour productivity model with a typical integrated assessment model using shared socioeconomic pathways. It simulates China's economic development and carbon emission levels under both baseline and carbon-neutral policy scenarios, evaluating the economic costs and benefits of emission reduction policies aimed at achieving carbon neutrality. These findings reveal the following:(1) The economic costs of emission reduction policies are projected to peak between 2050 and 2060, ranging from 0.41% to 9.37% of total GDP in the baseline scenario, primarily due to increased energy prices and R&D investments. These costs are expected to decline rapidly after 2070.(2) China's carbon-neutral policies will mitigate global warming, with the economic benefits of mitigation projected to reach 5.65% to 17.24% of China's total GDP by 2100.(3) Lowcarbon scenarios SSP1 and SSP4 could significantly reduce initial economic costs and advance the onset of net economic gains to 2060. This integrated assessment confirms that China's carbon neutrality target offers substantial net economic benefits in the long term. To minimize initial economic costs, efforts should focus on enhancing consumption-side transitions, upgrading lowcarbon technologies, and adopting new energy sources.

关键词： Climate change China Carbon neutrality Economic effects Policy

同方期刊数据库

Extended finite element methods for optimal control problems governed by Poisson equation in non-convex domains

在线全文

学校读者我要写书评

暂无评论

science China Mathematics 2021年第8期64卷 1917-1934页

作者： Tao Wang Chaochao Yang Xiaoping Xie School of Mathematics Sichuan UniversityChengdu 610064China current address:School of science Chongqing University of TechnologyChongqing 400054China

This paper analyzes two extended finite element methods(XFEMs)for linear quadratic optimal control problems governed by Poisson equation in non-convex *** follow the variational discretization concept to discretize the continuous problems,and apply an XFEM with a cut-off function and a classic XFEM with a fixed enrichment area to discretize the state and co-state *** error estimates are derived for the state,co-state and *** results confirm our theoretical results.

关键词： extended finite element method optimal control non-convex domain variational discretization concept

维普期刊数据库

An embedded electron current layer observed at the edge of the plasma sheet in the Earth’s magnetotail

在线全文

学校读者我要写书评

暂无评论

Earth and Planetary Physics 2025年第1期9卷 148-158页

作者： ChenChen Zhan RongSheng Wang QuanMing Lu San Lu XinMin Li Deep Space Exploration Laboratory/School of Earth and Space sciences University of Science and Technology of ChinaHefei 230026China Chinese Academy of sciences(CAS)Center for Excellence in Comparative Planetology/CAS Key Laboratory of Geospace Environment/Anhui Mengcheng National Geophysical Observatory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical science and Technology Harbin 150001China

The formation of an embedded electron current sheet within the magnetotail plasma sheet has been poorly *** this article,we present an electron current layer detected at the edge of the magnetotail plasma *** ions were demagnetized inside the electron current layer,but the electrons were still frozen in with the magnetic field ***,this decoupling of ions and electrons gave rise to a strong Hall electric field,which could be the reason for the formation of the embedded thin current *** magnetized electrons,the absence of the nongyrotropic electron distribution,and negligible energy dissipation in the layer indicate that magnetic reconnection had not been triggered within the embedded thin current *** highly asymmetric plasma on the two sides of the current layer and low magnetic shear across it could suppress magnetic *** observations indicate that the embedded electric current layer,probably generated by the Hall electric field,even down to electron scale,is not a sufficient condition for magnetic reconnection.

关键词： magnetotail plasma sheet magnetic reconnection

Pulsed high-current discharge in water:adiabatic model of expanding plasma channel and acoustic wave

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plasma science and Technology 2022年第3期24卷 123-129页

作者： A KOZYREV A ZHERLITSYN N SEMENIUK Institute of High-current Electronics Russian Academy of SciencesTomsk 634055Russia

This paper presents the results of a theoretical and experimental study of the use of a pulsed discharge in water to obtain a strong acoustic wave in a liquid medium.A discharge with a current amplitude of 10 kA,a duration of 400 ns,and an amplitude pulsed power of 280 MW in water at atmospheric pressure created an expanding acoustic wave with an amplitude of more than 100 *** describe the formation of the discharge channel,an isothermal plasma model has been developed,which made it possible to calculate both the expansion dynamics of a high-current channel and the strong acoustic wave generated by *** calculations show that the number density of plasma in the channel reaches 10^(20) cm^(-3),while the degree of water vapor ionization is about 10%,and the channel wall extends with a velocity of 500 m s^(−1).The calculations for the acoustic wave are in good agreement with measurements.

关键词： plasma applications electrical discharge in water dense plasma channel

维普期刊数据库

Synthesis of High Magnetic Moment CoFe Nanoparticles via Interfacial Diffusion in Core/Shell Structured Co/Fe Nanoparticles

在线全文

学校读者我要写书评

暂无评论

Nano Research 2009年第5期2卷 380-385页

作者： Chao Wang Sheng Peng Lise-Marie Lacroix Shouheng Sun Department of Chemistry Brown UniversityProvidenceRhode Island 02912USA current address:Materials science Division Argonne National LaboratoryArgonneIL 60439USA

We report the synthesis of high magnetic moment CoFe nanoparticles via the diffusion of Co and Fe in core/shell structured Co/Fe *** an organic solution,Co nanoparticles were coated with a layer of Fe to form a Co/Fe core/shell *** raising the solution temperature led to inter-diffusion of Co and Fe and formation of CoFe alloy *** nanoparticles have high saturation magnetization of up to 192 emu/g CoFe and can be further stabilized by thermal annealing at 600℃.

关键词： CoFe nanoparticles core/shell nanoparticles magnetic nanoparticles chemical synthesis

Tectonic modes of mantle convection and their implications for Earth's tectonic evolution based on three-dimensional numerical simulations

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

science China Earth sciences 2025年第1期68卷 270-296页

作者： Song XIANG Jinshui HUANG Bingcheng WU School of Earth and Space sciences University of Science and Technology of China CAS Center of Excellence in Comparative Planetary Studies

Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell domain. The five tectonic convective modes are non-plate mobile-lid, plate-like mobile-lid, episodic plate-like mobile-lid, episodic stagnant-lid, and stagnant-lid convective modes, respectively. The typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness, mobility, and their standard deviations are presented and discussed. The results show that the yield stress of the lithosphere has profound effects on the tectonic convective *** the gradual increase of yield stress, the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five modes. Additionally, as the Rayleigh number increases, the range of yield stress for the platelike mobile-lid convective mode decreases, and the dimensionless transition stress between different tectonic modes ***, the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number, but decreases between other tectonic modes. Furthermore, we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate, with the transition stress decreasing as the internal heating rate increases. The fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa, which aligns with the strength of serpentinized mantle rock determined by experimental petrography. If the Archean mantle was 300°C warmer than it is today, then the Earth was in an episodic stagnant-lid convective mode. The tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal evolution. If the lithospheric strength w

关键词： Tectonic mode of mantle convection Plate-like mobile-lid convection Episodic plate-like mobile-lid convection Episodic stagnant-lid convection Plate tectonics and tectonic evolution of the Earth