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Cobalt-catalyzed reductive alkynylation to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))bonds

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Chinese Chemical Letters 2024年第7期35卷 253-258页

作者： Lei Wan Yizhou tong Xi lu yao Fu Hefei National Research Center for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China

Transition-metal-catalyzed cross-electrophile coupling has emerged as a reliable method for constructing carbon–carbon ***,we report a general method,cobalt-catalyzed reductive alkynylation,to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))*** presented reaction has a broad substrate scope,enabling the efficient cross-electrophile coupling between alkynyl bromides with alkyl halides and aryl or alkenyl(pseudo)*** presented reaction is conducted under mild conditions,tolerating many functional groups,thus suitable for the modification and synthesis of biologically active molecules.

关键词： Cobalt-catalysis Cross-electrophile coupling Carbon-carbon bond formation Reductive alkynylation Alkyne synthesis

Visible-light-driven photocatalysis degradation of antibiotic pollutants by La-doped CeO_(2) nanorods:synergy of La doping and oxygen vacancy

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Rare Metals 2024年第7期43卷 3134-3145页

作者： Shi-Hai Cao Jing-Ru Qu Yu-Qi Zhao Yun-tong Sun Wen-tong Gao Bing Han yao lu College of Environmental Engineering Nanjing Institute of TechnologyNanjing 211167China School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing 211167China School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological UniversitySingapore 637459Singapore Institute of Environmental Health and Ecological Security School of Environment and Safety EngineeringJiangsu UniversityZhenjiang 212013China Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment Suzhou University of Science and TechnologySuzhou215009China

Elemental doping is an effective strategy to enhance photocatalytic activity and extend the light absorption range of single-component *** this work,a series of La-doped CeO_(2) nanorods(La-CeO_(2)-x) with La content of 1 wt%-15 wt% are synthesized by a simple hydrothermal method and further used as photocatalyst for sulfamerazine(SMR) *** prepared La-CeO_(2)-x nanorods exhibit a great improvement in electron-hole pair migration and visible-light response due to the synergistic effect of abundant oxygen vacancies and heterogeneous elements(La).Consequently,La-CeO_(2)-x exhibited excellent visible-light photocatalytic performances and chemical stability for SMR degradation,the La-CeO_(2)-5 sample achieved the highest SMR degradation rate of 81%,which was 3.4 times higher than that of the original CeO_(2).Furthermore,three possible degradation pathways of SMR in La-CeO_(2) photocatalytic reactions were proposed by liquid chromatography-mass spectrometry ***,density functional theory calculations were carried out to provide an in-depth understanding of the structure-performance *** its excellent properties and better photocatalytic performance,this study demonstrates that La doping in CeO_(2) is an effective way to increase oxygen vacancy and improve the photochemical properties of photocatalysts.

关键词： CeO_(2)nanorod La-doped Photocatalysis Oxygen vacancy Sulfamerazine

Selection Method for New Energy Output Guaranteed Rates Considering Optimal Energy Storage Configuration

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 539-547页

作者： Xin Cheng tong Wu Wei yao Yan Yang Guangdong Power Grid Corporation Guangzhou 510620China State Key Laboratory of Advanced Electromagnetic Engineering and Technology and School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The output of new energy represented by wind power and photovoltaic power features volatility and randomness. It is a practical approach to use the guaranteed rate with statistical characteristics to analyze the output coefficient of new energy. However, there is a lack of analysis and demonstration on the value of the new energy output guaranteed rate. To solve this problem, a selection method for the new energy output guaranteed rate considering optimal energy storage configuration is proposed. First, the influence of the new energy output guaranteed rate on the new energy output coefficient is analyzed. Secondly, with the goal of minimizing the comprehensive costs, an optimal configuration model of energy storage based on the output guaranteed rate of new energy is constructed, and particle swarm optimization is used for the optimization solution. Then, according to the optimal energy storage configuration results under different guaranteed rates, a reasonable new energy output guaranteed rate is determined by maximizing the comprehensive benefits obtained from energy storage. Finally, an example applied to the power grid in an area of Guangdong in Southern China is provided to illustrate the effectiveness of the proposed method.

关键词： Energystorage optimization guaranteed output guaranteed rate new energy consumption

Initial costates derived by near-optimal reference sequence and least-squares method

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Chinese Journal of Aeronautics 2024年第5期37卷 377-391页

作者： Shaozhao lu yao ZHANG Quan HU School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

In this paper,we present a novel initial costates solver for initializing time-optimal trajectory problems in relative motion with continuous low *** proposed solver consists of two primary components:training a Multilayer Perceptron(MLP)for generating reference sequence and Time of Flight(TOF)to the target,and deriving a system of linear algebraic equations for obtaining the initial *** overcome the challenge of generating training samples for the MLP,the backward generation method is proposed to obtain five different training *** training database and sample form are determined by analyzing the input and output correlation using the Pearson correlation *** best-performing MLP is obtained by analyzing the training results with various hyper-parameter combinations.A reference sequence starting from the initial states is obtained by integrating forward with the near-optimal control vector from the output of ***,a system of linear algebraic equations for estimating the initial costates is derived using the reference sequence and the necessary conditions for *** results demonstrate that the proposed initial costates solver improves the convergence ratio and reduce the function calls of the shooting ***,Monte-Carlo simulation illustrates that the initial costates solver is applicable to different initial velocities,demonstrating excellent generalization ability.

关键词： Relative motion Expanding training database Multilayer perceptron Initial costates Least-squares method

Dual-assisted high-precision tracking technique for wideband multiplexed signals in new generation GNSS

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Satellite Navigation 2024年第1期5卷 52-73页

作者： Yunhan Qi Zheng yao Mingquan lu Department of Electronic Engineering Tsinghua UniversityBeijing100084China Beijing National Research Center for Information Science and Technology Beijing100084China

With the evolution of Global Navigation Satellite System(GNSS),new generation GNSS signals have adopted the dual-frequency multiplexing modulation techniques,which jointly modulate multiple signals located on multiple sub-frequencies into a Wideband Multiplexed Signal(WMS).Although WMSs were proposed initially to reduce the complexity of satellite transmitters and improve the transmission efficiency of signals,their multi-component structures and wide root mean square bandwidths introduced by high-frequency subcarriers also provide the possibility to improve the GNSS ranging ***,this paper proposes a Dual-assisted Multi-component Tracking(DMT)technique,which can not only fully use high-frequency subcarriers in WMSs,but also effectively track carrier,subcarrier,and code by jointly utilizing all components in *** this paper,the tracking and ranging performances of DMT are comprehensively analyzed theoretically and by simulation and real *** results show that compared with existing WMS tracking methods,DMT can achieve tracking results with lower tracking jitters and ranging results with higher precision,providing a highly advantageous solution for new generation GNSS signal processing.

关键词： Wideband multiplexed signal Dual-assisted Multi-component High precision tracking

A state-of-the-art review of the development of self-healing concrete for resilient infrastructure

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 151-169页

作者： Dong lu Xi JIANG yao ZHANG Shaowei ZHANG Guoyang lu Zhen LENG Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China Laboratory of Fire Safety School of Safety Engineering and Emergency ManagementShijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Architecture and Civil Engineering City University of Hong KongHong Kong 999077China

The brittleness of cement composites makes cracks almost inevitable,producing a serious limitation on the lifespan,resilience,and safety of concrete *** address this brittleness,self-healing concrete has been developed for regaining its mechanical and durability properties after becoming cracked,thereby promising sustainable development of concrete *** paper provides a comprehensive review of the latest developments in self-healing *** begins by summarizing the methods used to evaluate the self-healing efficiency of ***,it compares strategies for achieving healing *** then discusses the typical approaches for developing self-healing ***,critical insights are proposed to guide future studies on the development of novel self-healing *** review will be useful for researchers and practitioners interested in the field of self-healing concrete and its potential to improve the durability,resilience,and safety of concrete infrastructure.

关键词： resilient infrastructure sustainable concrete self-healing cracks

Facile interfacial synthesis of gold micronails with adjustable length and roughness and their superior SERS properties for the detection of p-aminothiophenol Author links open overlay panel

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Particuology 2024年第8期91卷 333-340页

作者： Hang Li Kaisheng yao Tianhang Liu Weiwei lu School of Chemistry and Chemical Engineering Henan University of Science and TechnozlogyLuoyang471023China School of Physics and Engineering Henan University of Science and TechnologyLuoyang471023China

Au hierarchical architectures with special morphology and structures are strongly desired in varied ***,a simple synthesis method was developed for the one-step preparation of Au micronails(MNs)at the planar liquid-liquid interface under mild *** well-defined Au MNs were grown and constructed at CHCl_(3)-H_(2)O interface at room temperature using aniline in CHCl_(3)as reducing agent and HAuCl_(4)in H_(2)O as precursor and no surfactant or seed is *** intriguing Au MNs with rough surface consist of big heads and thin rods,just like iron nails in ***,through simple changing the reagent concentrations,the length and surface roughness of Au MNs can be adjusted *** effects of a series of factors on the morphology and structure of the products are studied in *** p-aminothiophenol as a molecular probe,the as-obtained Au MNs all exhibit dramatically improved surface enhanced Raman scattering sensitivity and high reproducibility,the enhancement factor and limit of detection of Au MNs are 5.4×10^(5)and 1.0×10^(-10),respectively.

关键词： Au micronails Liquid-liquid interface synthesis Surface enhanced Raman scattering P-aminothiophenol

Ambient particle composition and toxicity in 31 major cities in China

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Fundamental Research 2024年第3期4卷 505-515页

作者： lu Zhang Maosheng yao State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

Current assessment of air quality or control effectiveness is solely based on particulate matter(PM)mass levels,without considering their toxicity differences in terms of health ***,we collected a total of 465 automo-bile air conditioning filters from 31 major Chinese cities to study the composition and toxicity of PM at a national *** assay showed that normalized PM toxicity(NIOG)in different Chinese cities varied greatly from the highest 4.99×10^(-3)for Changsha to the lowest 7.72×10^(-4)for ***0G values were observed to have significant correlations with annual PM_(10) concentration(r=-0.416,p=0.020)and some PM components(total fungi,so.2-and calcium element).The concentrations of different elements and water-soluble ions in PM also varied by several orders of magnitude for 31 cities in *** concentrations in PM analyzed using limulus amebocyte lysate assay ranged from 2.88 EU/mg PM(Hangzhou)to 62.82 EU/mg PM(Shijiazhuang)among 31 Chinese ***,real-time qPCR revealed 10~100-fold differences in total bacterial and fungal levels among 31 Chinese *** concentrations of chemical(water soluble ions and trace elements)and bi-ological(fungi,bacteria and endotoxin)components in PM were found to be significantly correlated with some meteorological factors and gaseous pollutants such as SO_(2).Our results have demonstrated that PM toxicity from 31 major cities varied greatly up to 6.5 times difference;and components such as fungi and SO_(4)^(2-)in PM could play important roles in the observed PM *** city-specific air pollution control strategy that integrates toxicity factors should be enacted in order to maximize health and economic *** work also provides a comprehensive view on the overall PM pollution situation in China.

关键词： PM toxicity Oxidative potential Biologicals Chemical components Endotoxin

Experimental Study on the Sinking and Leveling of A Large-Capacity Offshore Wind Turbine Five-Bucket Foundation in Sand

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China Ocean Engineering 2024年第4期38卷 586-601页

作者： LIAN Ji-jian ZHU Hang GUO yao-hua WANG Hai-jun YU tong-shun State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China Tianjin University of Technology Tianjin 300384China College of Engineering Ocean University of ChinaQingdao 266100China

As offshore wind farms expand into deeper and farther ocean regions and the unit capacity of offshore wind turbines(OWTs)increases,there is a pressing need for a new foundation structure that can accommodate deep-sea conditions and support large capacities while maintaining economical and *** meet this goal of integrated transportation and one-step installation,a novel five-bucket jacket foundation(FBJF),with its suction installation and leveling methods in sand,has been proposed,analyzed and experimentally ***,seepage failure experiments of the FBJF at various depths were conducted,and a formula for calculating the critical suction of seepage failure suitable for the FBJF in sand was chosen and recommended for use with a range of values for the permeability coefficient ***,through leveling experiments of the FBJF at different depths,the maximum adjustable leveling angle during the sinking process was defined using seepage failure and the adjustable leveling angle of the foundation as control *** leveling control strategies were proposed and ***,an automatic sinking and leveling control system for the FBJF was developed and experimentally verified for feasibility.

关键词： offshore wind turbine(OWT) bucket foundation seepage failure suction installation