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Ti3C2Tx-MXene-聚二烯丙基二甲基氯化铵-还原氧化石墨烯复合膜修饰电极检测碘酸盐

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分析化学 2024年第3期52卷 336-350页

作者：王焕焕张爱萍李开林李国荣于浩延安大学化学与化工学院陕西省化学反应工程重点实验室

通过静电组装法制备了Ti3C2Tx-MXene-聚二烯丙基二甲基氯化铵（PDDA）-还原氧化石墨烯（r GO）复合材料（Ti3C2Tx-MXene-PDDA-r GO），将其修饰在玻碳电极（GCE）表面，用于碘酸盐的电化学检测。采用氢氟酸（HF）刻蚀钛碳化铝（Ti3Al C... 详细信息

通过静电组装法制备了Ti3C2Tx-MXene-聚二烯丙基二甲基氯化铵（PDDA）-还原氧化石墨烯（r GO）复合材料（Ti3C2Tx-MXene-PDDA-r GO），将其修饰在玻碳电极（GCE）表面，用于碘酸盐的电化学检测。采用氢氟酸（HF）刻蚀钛碳化铝（Ti3Al C2）法制备了Ti3C2Tx-Mxene，以水合肼为还原剂制备了PDDA功能化的r GO（PDDA-r GO）。将MXene加入PDDA-r GO分散液中，通过带正电的PDDA与表面带负电荷的Ti3C2Tx-MXene间的静电相互作用，制得Ti3C2Tx-MXene-PDDA-r GO复合材料。采用扫描电镜（SEM）、能谱（EDS）、X射线粉末衍射仪（XRD）及拉曼光谱仪（Raman spectroscopy）等对其组成和形貌进行了表征。采用此材料修饰GCE，研究了碘酸根（IO3–）在修饰电极上的电化学行为。结果表明，带正电荷的聚电解质PDDA通过静电作用将带负电荷的Ti3C2Tx-MXene和r GO片层组装在一起，实现了MXene片层的超薄、高稳定性负载，增大了材料的活性面积。MXene和r GO提高了材料的电化学活性，PDDA对IO3–的静电吸引也加快了IO3–的传质效率。在各因素的协同作用下，此材料对碘酸盐的电化学还原表现出较强的催化活性。在0.10 mol/L HCl中，采用安培法检测碘酸盐的线性范围为1.0×10-7～4.7×10-3mol/L，检出限为4.5×10-8mol/L （S/N=3），灵敏度为192μA/（mmol/L）。此修饰电极具有检出限低、灵敏度高和线性范围宽的特点，可用于加碘食盐中碘酸盐含量的测定。

关键词： Ti3C2Tx-MXene 聚二烯丙基二甲基氯化铵还原氧化石墨烯电化学传感碘酸盐

Diagnosis,treatment and prevention of severe acute respiratory syndrome coronavirus 2 infection in children:experts'consensus statement updatedforthe Omicron variant

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World Journal of Pediatrics 2024年第3期20卷 272-286页

作者： Rong-Meng Jiang Zheng-De Xie Yi Jiang Xiao-Xia Lu Run-Ming Jin Yue-Jie Zheng Yun-Xiao Shang Bao-Ping Xu Zhi-Sheng liu Gen Lu Ji-Kui Deng Guang-Hua liu Xiao-Chuan Wang Jian-She Wang Lu-Zhao Feng Wei liu Yi Zheng Sai-Nan Shu Min Lu Wan-Jun Luo Miao liu Yu-Xia Cui Le-Ping Ye A-Dong Shen Gang liu li-Wei Gao li-Juan Xiong Yan Bai li-kai lin Zhuang Wei Feng-Xia Xue Tian-You Wang Dong-Chi Zhao Jian-Bo Shao Daniel Kwok-keung Ng Gary Wing-kin Wong Zheng-Yan Zhao Xing-Wang li Yong-Hong Yang Kun-ling Shen Diagnosis and Treatment Center of Infectious Diseases Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Beijing Key Laboratory of Pediatric Respiratory Infection Diseases Key Laboratory of Major Diseases in ChildrenMinistry of EducationNational Clinical Research Center for Respiratory DiseasesResearch Unit of Critical Infection in ChildrenChinese Academy of Medical Sciences2019RU016Laboratory of Infection and VirologyBeijing Pediatric Research InstituteBeijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBeijing 100045China Department of Pediatrics Renmin Hospital of Wuhan UniversityWuhan 430060China Department of Respiratory Wuhan Children's HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430016China Department of Pediatrics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Respiratory Shenzhen Children's HospitalShenzhen 518038China Department of Pediatric Respiratory Shengjing Hospital Affiliated to China Medical UniversityShenyang 110004China Department of Respiratory Beijing Children's HospitalCapital Medical UniversityNational Clinical Research Center for Respiratory DiseasesNational Center for Children's HealthBeijing 100045China Department of Neurology Wuhan Children's HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430016China Department of Respiratory Guangzhou Women and Children's Medical CenterGuangzhou 510623China Department of Infectious Diseases Shenzhen Children's HospitalShenzhen 518038China Department of Pediatrics Fujian Branch of Shanghai Children's Medical CenterFujian Children's HospitalFuzhou350005China Department of Clinical Immunology and Allergy Children's Hospital of Fudan UniversityNational Center for Children's HealthShanghai 201102China Department of Infectious Diseases Children's Hospital of Fudan UniversityNational Center for Children's Health.Shanghai

It has been more than 3 years since the novel coronavirus(SARS-CoV-2)pandemic raged *** coronavirus disease 2019(COVID-19)has greatly influenced human *** to data from the World Health Organization(WHO),there were ove... 详细信息

关键词： prevention infection statement

Path Planning and Tracking Control for Parking via Soft Actor-Critic Under Non-Ideal Scenarios

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 181-195页

作者： Xiaolin Tang Yuyou Yang Teng liu Xianke lin kai Yang Shen li IEEE the College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China the Clinical Research Center and Medical Pathology Center Chongqing University Three Gorges HospitalChongqing UniversityWanzhou 404000 the Department of Automotive and Mechatronics Engineering Ontario Tech UniversityOshawa ON LIG OC5Canada the School of Civil Engineering Tsinghua UniversityBeijing 100084China

Parking in a small parking lot within limited space poses a difficult task. It often leads to deviations between the final parking posture and the target posture. These deviations can lead to partial occupancy of adjacent parking lots, which poses a safety threat to vehicles parked in these parking lots. However, previous studies have not addressed this issue. In this paper, we aim to evaluate the impact of parking deviation of existing vehicles next to the target parking lot(PDEVNTPL) on the automatic ego vehicle(AEV) parking, in terms of safety, comfort, accuracy, and efficiency of parking. A segmented parking training framework(SPTF) based on soft actor-critic(SAC) is proposed to improve parking performance. In the proposed method, the SAC algorithm incorporates strategy entropy into the objective function, to enable the AEV to learn parking strategies based on a more comprehensive understanding of the environment. Additionally, the SPTF simplifies complex parking tasks to maintain the high performance of deep reinforcement learning(DRL). The experimental results reveal that the PDEVNTPL has a detrimental influence on the AEV parking in terms of safety, accuracy, and comfort, leading to reductions of more than 27%, 54%, and 26%respectively. However, the SAC-based SPTF effectively mitigates this impact, resulting in a considerable increase in the parking success rate from 71% to 93%. Furthermore, the heading angle deviation is significantly reduced from 2.25 degrees to 0.43degrees.

关键词： Automatic parking control strategy parking deviation(APS) soft actor-critic(SAC)

Nitrogen addition increased resistance of resident plant community to Solidago canadensis invasion by altering allelopathic effect

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JOURNAL OF PLANT ECOLOGY 2024年第2期17卷 110-121页

作者： Cai, Jing-Fang Sun, kai li, lin A, Si-Ha Shen, Yi-Luan li, Hong-li Beijing Forestry Univ Sch Ecol & Nat Conservat Beijing 100083 Peoples R China Beijing Forestry Univ Key Lab Ecol Protect Yellow River Basin Natl Forestry & Grassland Adm Beijing 100083 Peoples R China

Allelopathy plays an important role in the interaction between invasive and resident plants. Atmospheric nitrogen (N) deposition has become a global problem, but it is unclear whether N enrichment affects the interaction between invasive and resident plants by affecting their allelopathy. Thus, we performed a greenhouse experiment in which the resident plant community was grown under two levels of invasion by S. canadensis (invasion vs. no invasion) and fully crossed with two levels of allelopathy (with or without adding activated carbon) and two levels of N addition (with or without). The resident plant communities were constructed with eight herbaceous species that often co-occur with S. canadensis. The results showed that both allelopathy of S. canadensis and the resident plants had obvious positive effects on their own growth. Nitrogen addition had more obvious positive effects on the resident plants under invasion than those that were not invaded. Moreover, N addition also altered the allelopathy of resident plants. Specifically, N addition improved the allelopathy of resident plants when they were invaded but decreased the allelopathy of resident plants when they grew alone. Although nitrogen addition had no obvious effect on S. canadensis, it reduced the allelopathy of S. canadensis. These results suggest that N addition could improve the resistance of resident plants to invasion by improving the allelopathy of resident plants and reducing the allelopathy of S. canadensis. These findings provide a scientific basis to manage and control the S. canadensis invasion.

关键词： allelochemicals biological invasion nutrient input nitrogen addition resident plants Solidago canadensis DEPOSITION COMPETITION DIVERSITY EVOLUTION RESPONSES SUCCESS

Superhydrophobic melamine sponge prepared by radiation-induced grafting technology for efficient oil-water separation

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Nuclear Science and Techniques 2024年第9期35卷 103-114页

作者： Ying Sun Wen-Rui Wang Dan-Yi li Si-Yi Xu lin lin Man-li Lu kai Fan Chen-Yang Xing lin-Fan li Ji-Hao li Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Architecture and Materials Chongqing College of Electronic EngineeringChongqing 401331China Center for Stretchable Electronics and NanoSensors Key Laboratory of Optoelectronic Devices and Systems of Ministry of EducationCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

This paper presents a superhydrophobic melamine(ME)sponge(ME-g-PLMA)prepared via high-energy radiation-induced in situ covalent grafting of long-alkyl-chain dodecyl methacrylate(LMA)onto an ME sponge for efficient oil–water *** obtained ME-g-PLMA sponge had an excellent pore structure with superhydrophobic(water contact angle of 154°)and superoleophilic *** can absorb various types of oils up to 66–168 times its *** ME-g-PLMA sponge can continuously separate oil slicks in water by connecting a pump or separating oil underwater with a gravity-driven *** addition,it maintained its highly hydrophobic properties even after long-term immersion in different corrosive solutions and repeated oil *** modified ME-g-PLMA sponge exhibited excellent separation properties and potential for oil spill cleanup.

关键词： Radiation-induced graft polymerization Oil–water separation Sponge Superhydrophobic

Thermal Decomposition and Oxidative Decomposition Mechanism of HFC-134a by Experimental and DFT Method

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Journal of Thermal Science 2024年第5期33卷 1990-2003页

作者： XU Yunting ZHANG kai DAI Xiaoye SHI lin Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China

In response to the Kigali Amendment to the Montreal Protocol and global low-carbon emission environmental requirements,the phase-out and decomposition of numerous HFC refrigerants have become urgent,necessitating efficient and mild decomposition *** study investigates the thermal decomposition and oxidative thermal decomposition pathways of the typical hydrofluorocarbon refrigerant HFC-134a,employing a combination of experimental and quantum chemical DFT simulation *** chemical simulations reveal that the initial reaction bond cleavage serves as the rate-determining step during the thermal decomposition process,with the most easily detectable closed-shell products including CF_(2)=CHF,HF,CH_(3)F,CHF_(3),CH_(2)F_(2),and CF_(4).Reactive oxygen species can significantly reduce the Gibbs free energy barrier for HFC-134a *** achieve efficient degradation of HFC-134a,appropriate catalysts should be developed and selected to increase the level of reactive oxygen species in the reaction *** studies further corroborate that HFC-134a may undergo degradation through distinct reaction pathways under varying temperature(240℃to360℃)and pressure(0.1 MPa to 4.5 MPa)conditions,in agreement with simulation predictions.

关键词： HFC-134a pyrolysis oxidative thermal decomposition DFT refrigerant

Solid solution strategy modulated defects engineering of(Cr_(1-x)V_(x))_(2)AlC MAX phase toward superior electromagnetic wave absorption

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Rare Metals 2024年第7期43卷 3205-3219页

作者： Ji-lin Gou Yu-kai Chang Shu liu Peng-Hui li Ping-Hao Cui Qian-Ku Hu li-Bo Wang Xin Zhang Jun-kai Wang Qi-Xun Xia Ai-Guo Zhou School of Materials Science and Engineering Henan Polytechnic UniversityJiaozuo 454003China Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

Defects engineering is an effective strategy for manipulating electromagnetic parameters and enhancing electromagnetic wave(EMW)absorption ***,the relationship between them is not clear,especially in solid solution *** this work,a series of(Cr_(1-x)V_(x))_(2)AlC MAX phase solid solutions with layered structure were prepared via tuning the ratio of Cr and V to explore their EMW absorption *** experimental results indicated that the doping of V atoms at the M-site could effectively regulate its impedance matching and EMW absorption properties by introducing appropriate numbers of defects in the crystal,such as twin boundaries,dislocations and lattice *** them,if Cr:V=3:1,Cr_(1.5)V_(0.5)AlC,as radar absorption materials,could reach a strong reflection loss of-51.8 dB at the frequency of 12.8 GHz under an ultra-thin thickness of 1.3 *** reflection loss value could attain-10 dB in a wide frequency range of 2.7-18 GHz and thickness range of 1-5 *** addition,after high temperature and acid-alkali immersion treatment,this sample still had good EMW absorption capability,and the effective absorption bandwidth was enhanced from 2.3 to 2.6 GHz after concentrated acid immersion or 3.1 GHz after concentrated alkali *** work has great reference significance for the research and development of high-performance MAX-based EMW absorption materials in harsh environments.

关键词： MAX phases Solid solution Defects engineering Electromagnetic wave absorption Harsh environments

Universal and efficient hybrid modeling and direct slicing method for additive manufacturing processes

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Advances in Manufacturing 2024年第2期12卷 300-316页

作者： Sen-lin Wang li-Chao Zhang Chao Cai Ming-kai Tang Si Chen Jiang Huang Yu-Sheng Shi State Key Laboratory of Materials Processing and Die and Mould Technology Huazhong University of Science and TechnologyWuhan430074People’s Republic of China School of Machinery and Automation Wuhan University of Science and TechnologyWuhan430081People’s Republic of China

Model design and slicing contour generation in additive manufacturing(AM)data processing face challenges in terms of efficiency and scalability when stereolithography files generated by complex functionally graded structures have millions of *** paper proposes a hybrid modeling and direct slicing method for AM to efficiently construct and handle complex three-dimensional(3D)*** 3D solids,including conformal multigradient structures,were uniformly described using a small amount of data via signed distance *** hybrid representations were quickly discretized into numerous disordered directed lines using an improved marching squares *** establishing a directional HashMap to construct the topological relationship between lines,a connecting algorithm with linear time complexity is proposed to generate slicing contours for *** method replaces the mesh reconstruction and Boolean operation stages and can efficiently construct complex conformal gradient models of arbitrary topologies through hybrid ***,the time and memory consumption of direct slicing are much lower than those of previous methods when handling hybrid models with hundreds of millions of faces after mesh reconstruction.

关键词： Additive manufacturing(AM) Hybrid modeling Direct slicing Signed distance field

Discrete Boltzmann model with split collision for nonequilibrium reactive flows

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Communications in Theoretical Physics 2024年第8期76卷 164-186页

作者： Chuandong lin kai H Luo Huilin Lai Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Department of Mechanical Engineering National University of Singapore10 Kent Ridge Crescent119260Singapore Department of Mechanical Engineering University College LondonTorrington PlaceLondon WC1E 7JEUnited Kingdom School of Mathematics and Statistics Key Laboratory of Analytical Mathematics and Applications(Ministry of Education)Fujian Key Laboratory of Analytical Mathematics and Applications(FJKLAMA)Center for Applied Mathematics of Fujian Province(FJNU)Fujian Normal University350117 FuzhouChina

A multi-relaxation-time discrete Boltzmann model(DBM) with split collision is proposed for both subsonic and supersonic compressible reacting flows, where chemical reactions take place among various components. The physical model is based on a unified set of discrete Boltzmann equations that describes the evolution of each chemical species with adjustable acceleration, specific heat ratio, and Prandtl number. On the right-hand side of discrete Boltzmann equations, the collision,force, and reaction terms denote the change rates of distribution functions due to self-and crosscollisions, external forces, and chemical reactions, respectively. The source terms can be calculated in three ways, among which the matrix inversion method possesses the highest physical accuracy and computational efficiency. Through Chapman-Enskog analysis, it is proved that the DBM is consistent with the reactive Navier-Stokes equations, Fick's law and the Stefan-Maxwell diffusion equation in the hydrodynamic limit. Compared with the one-step-relaxation model, the split collision model offers a detailed and precise description of hydrodynamic, thermodynamic, and chemical nonequilibrium effects. Finally, the model is validated by six benchmarks, including multicomponent diffusion, mixture in the force field, Kelvin-Helmholtz instability, flame at constant pressure, opposing chemical reaction, and steady detonation.

关键词： discrete Boltzmann method reactive flow detonation nonequilibrium effect