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Wheat straw return can lead to biogenic toluene emissions

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Journal of Environmental Sciences 2023年第2期124卷 281-290页

作者： Ting Wu xiaoyu zhao Mengdi Liu Juan zhao Xinming Wang School of Ecology and Environment Anhui Normal UniversityWuhu 241000China Center of Cooperative Innovation for Recovery and Reconstruction of Degraded Ecosystem in Wanjiang City Belt Wuhu 241000China State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

As a common practice in agricultural system,straw return has been reported to release a large number of trace gases and attractedmuch ***,the role of straw return in toluene emission remains poorly *** this study we measured the emissions of toluene as well as other 50 volatile organic compounds(VOCs)from wheat straw return for 66 days under flooded and non-flooded conditions,*** results showed that substantial toluene was released from the returned wheat straw particularly under flooded condition,and primarily derived from the secondary *** emissions from the returned wheat straw were 36.8 and 8.45 mg C/kg,sharing 28.0%and 8.6%of total VOCs released,and over 90% of toluene emissions occurred between days 24-56 and 0-17 under flooded and non-flooded conditions,*** emission rates of toluene were relatively high but decreased sharply at the beginning 2 days,and then was steady until 24 days under the two moisture *** the initial decrease these rose again to form one“peak emission window”between days 24-56 under flooded condition,while these were still very low and steady until the end under non-flooded *** toluene emission rates significantly positively correlated with microbial biomass C under flooded condition,but negatively associated with bacteria and fungus number,microbial biomass C,and CO_(2) flux under non-flooded condition,suggesting that microorganism might play an important role in toluene emissions from wheat straw return.A rough estimate indicated that straw return might be important for biogenic toluene.

关键词： Toluene Boigenic volatile organic compounds(BVOCs) Emission profile Straw return

Blocking the defect sites on ultrathin Pt nanowires with Rh atoms to optimize the reaction path toward alcohol fuel oxidation

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Chinese Chemical Letters 2020年第7期31卷 1782-1786页

作者： xiaoyu zhao Huachao zhao Jiefang Sun Gang Li Rui Liu Tianjin Key Laboratory of Brine Chemical Engineering and Resource Eco-utilization College of Chemical Engineering and Materials ScienceTianjin University of Science and TechnologyTianjin 300457China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences.Beijing 100085China Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning Beijing Center for Disease Prevention and ControlBeijing 100013China

Anodic electrocatalyst plays the co re role in direct alcohol fuel cells(DAFCs),while traditional Pt-catalysts suffer from limited catalytic activity,high over potential and severe CO ***,by selectively depositing Rh atoms on the defective-sites of Pt nanowires(NWs),we developed a new Pt@Rh NW electrocatalyst that exhibited enhanced electrocatalytic performance for both methanol oxidation(MOR)and ethanol oxidation(EOR).Both cyclic voltammetry(CV) and in-situ infrared spectroscopy revealed that the presence of Rh atoms suppressed the generation of poisonous intermediates and completely oxidized alcohols molecule into *** resolusion spherical aberration corrected high-angle annular dark field scanning transmission electron microscopy(CS-HAADF-STEM) and energy-dispersive X-ray spectroscopy(EDS) mapping analysis revealed that Rh atoms were primarily deposited on the defective sites of Pt ***,the presence of Rh atoms also modified the electronic state of Pt atoms and therefore lowered the onset potential for alcohols oxidation *** work gives the first clear clue on the role of the defective sites of Pt nanocatalyst poisoning,and propose that selectively blocking these sites with trace amount of Rh is an effective strategy in designing advantageous electrocatalysts.

关键词： Nanowire catalyst Ethanol electrooxidation In situ FTIR Defect regulation Fuel cells

Monte Carlo simulations for two-dimensional Ising system far from equilibrium

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Chinese Science Bulletin 2007年第3期52卷 307-312页

作者： LEI XiaoWei ZHENG Ji zhao xiaoyu Department of Physics and Information Engineering Chongqing University of Arts and Sciences Chongqing 402160 China College of Applied Science and Technology Chongqing University of Art and Sciences Chongqing 402160 China

With a dynamic Monte Carlo simulation, which is free of critical slowing down, the critical behavior of two-dimensional Ising model at non-equilibrium states is investigated. We focus on the two-time autocorrelation function A(t, t' ) to identify the dynamic exponent z in two different evolution stages, quenched from a high temperature state and a completely ordered state to the critical state at TC, re-spectively. By using the heat-bath algorithm, the dynamic critical exponent is estimated as z ≈ 2.16. As a result, the universality of the scaling behavior is verified numerically, and the exponent λC is deter-mined complete by λC = β /ν for the evolutions from an initial completely ordered state.

关键词：二维Ising系统临界行为非平衡态弛豫相变蒙特卡洛模拟

A machine learning surrogate modeling benchmark for temperature field reconstruction of heat source systems

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Science China(Information Sciences) 2023年第5期66卷 162-181页

作者： Xiaoqian CHEN Zhiqiang GONG xiaoyu zhao Weien ZHOU Wen YAO Defense Innovation Institute Chinese Academy of Military Science

The temperature field reconstruction of heat source systems(TFR-HSS) with limited monitoring sensors in thermal management plays an important role in the real-time health detection systems of electronic equipment in engineering. However, prior methods with common interpolations usually cannot provide accurate reconstruction performance as required. In addition, no public dataset exists for the wide research of reconstruction methods to further boost reconstruction performance and engineering applications. To overcome this problem, this work develops a machine learning surrogate modeling benchmark for the TFRHSS task. First, the TFR-HSS task is mathematically modeled from a real-world engineering problem, and four types of computational modelings are constructed to transform the problem into discrete mapping ***, this work proposes a set of machine learning surrogate modeling methods, including general machine learning methods and deep learning methods, to advance the state-of-the-art methods over temperature field reconstruction. More importantly, this work develops a novel benchmark dataset, namely the temperature field reconstruction dataset(TFRD), to evaluate these machine learning surrogate modeling methods for the TFR-HSS task. Finally, a performance analysis of typical methods is given on the TFRD, which can serve as the baseline results on this benchmark.

关键词： temperature field reconstruction heat-source systems computational modeling temperature field reconstruction dataset machine learning surrogate modeling deep learning

Trajectory planning and base attitude restoration of dual-arm free-floating space robot by enhanced bidirectional approach

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Frontiers of Mechanical Engineering 2022年第1期17卷 2-17页

作者： Zongwu XIE xiaoyu zhao Zainan JIANG Haitao YANG Chongyang LI State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China Robotic System Department Jiangsu Jitri-Hust Intelligent Equipment TechnologyWuxi 214000China

When free-floating space robots perform space tasks,the satellite base attitude is disturbed by the dynamic *** disturbance of the base orientation may affect the communication between the space robot and the control center on *** this paper,the enhanced bidirectional approach is proposed to plan the manipulator trajectory and eliminate the final base attitude variation.A novel acceleration level state equation for the nonholonomic problem is proposed,and a new intermediate variable-based Lyapunov function is derived and solved for smooth joint trajectory and restorable base *** the method,the state equation is first proposed for dual-arm robots with and without end constraints,and the system stability is analyzed to obtain the system *** input modification further increases the system stability and simplifies the calculation *** are carried out in the end,and the proposed method is validated in minimizing final base attitude change and trajectory ***,the minute internal force during the coordinated operation and the considerable computing efficiency increases the feasibility of the method during space tasks.

关键词： free-floating space robot dual arm coordinated operation base attitude restoration bidirectional approach

Towards sparse sensor annotations:Uncertaintybased active transfer learning for airfoil flow field prediction

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Chinese Journal of Aeronautics 2024年第12期37卷 87-98页

作者： Yunyang ZHANG Xiaohu ZHENG Zhiqiang GONG Wen YAO xiaoyu zhao Defense Innovation Institute Chinese Academy of Military ScienceBeijing 100071China Intelligent Game and Decision Laboratory Beijing 100071China

Deep learning has been widely applied in surrogate modeling for airfoil flow field *** success of deep learning relies heavily on large-scale,high-quality labeled ***,acquiring labeled samples with complete annotations is prohibitively expensive,and the available annotations in practical engineering are often sparse due to limited *** leverage samples with sparse annotations,this paper proposes an uncertainty-based active transfer learning *** most valuable positions in the flow field are selected based on uncertainty for annotation,effectively improving prediction accuracy and reducing annotation *** method involves a novel active annotation based on synchronous quantile regression,which can mitigate the computational cost of query ***,a novel quantile levels-based consistency regularization is proposed to constrain the remaining unlabeled regions and further improve the model *** show that our method can significantly reduce prediction errors with only 1%extra annotations,and is a promising tool for achieving rapid and accurate flow field prediction.

关键词： Active transfer learning Uncertainty analysis Surrogate model Flow fields Sparse annotations

A Differential Game Based Approach Against Objective Function Attack in Cognitive Networks

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Chinese Journal of Electronics 2018年第4期27卷 879-888页

作者： FENG Guangsheng LIN Junyu zhao Qian WANG Huiqiang LYU Hongwu zhao xiaoyu HAN Jizhong LI Bingyang College of Computer Science and Technology Harbin Engineering University Institute of Information Engineering Chinese Academy of Sciences School of Computer and Information Engineering Harbin University of Commerce

We study the problem of defense strategy against Objective function attack(OFA) in Cognitive networks(CNs), where the network can be operated at the optimal state by adapting the parameters of its objective function. An OFA attacker can disrupt the parameter adaptation by interfering measures, which results in some operating parameters of the objective function deviating from their optimal settings. We first model the interactive process between the OFA attacker and defense system using differential game theory, and propose a defense strategy by introducing a new metric, namely, threat factor. Then,we obtain the optimal defense strategy by proving the existence of the saddle point of the proposed model. Moreover,this defense strategy is scale-free such that it can conquer a large number of OFAs in a decentralized way. Finally, we conduct extensive simulations to show that the proposed approach is effective.

关键词： Cognitive networks Objective function Operating parameter Saddle point

Monitoring the Status of Multi-Wave Omicron Variant Outbreaks-71 Countries,2021–2023

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China CDC weekly 2024年第41期6卷 1054-1058页

作者： Chuanqing Xu Lianjiao Dai Songbai Guo xiaoyu zhao Xiaoling Liu School of Science Beijing University of Civil Engineering and ArchitectureBeijingChina School of Mathematics Shandong UniversityJinan CityShandong ProvinceChina Hanshan Normal University Chaozhou CityGuangdong ProvinceChina.

What is already known about this topic?Analyzing the characteristics of epidemic development after the emergence of the severe acute respiratory syndrome virus 2 Omicron variants with its subvariants and the impact of income level inequalities on the coronavirus disease 2019(COVID-19)case-fatality ratio helps to better understand the spread of novel coronavirus *** is added by this report?The median time interval between the first and second waves of Omicron sub-variants was 70 days(interquartile spacing:43.75–91),and between the second and third waves was 87.5 days(interquartile spacing:49–119),which obeyed a lognormal *** case-fatality ratio of the first wave was significantly higher than that of the second and third *** the initial epidemic period,there was no significant geographic differences in the case-fatality ratio of the first wave,while the case-fatality ratio in countries with high income levels was significantly lower than in countries with other income *** are the implications for public health practice?We still need to pay attention to the COVID-19 pandemic,as inequalities in income levels have an impact on the case-fatality ratio during the early stages of Omicron *** most countries,strains of the virus are likely to move from low to high population prevalence after 2–4 months.

关键词： spacing inequalities wave

Hybrid ZnO@Au Nanorod Array for Fast and Repeatable Bacteria Inactivation

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Chinese Journal of Chemistry 2023年第17期41卷 2132-2142页

作者： Yu Liu xiaoyu zhao Xiaosa Zhang Xiaodan Jia Lie Wu Xiue Jiang College of Science Shenyang University of Chemical TechnologyShenyangLiaoning 110142China Shenyang National Laboratoryfor Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyangLiaoning 110016China State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of Scienc ChangchunJilin 130022China

Comprehensive Summary,The worldwide abuse of antibiotics and resultant antimicrobial resistance made the development of new antibacterial materials an urgent and significant ***,a hybrid ZnO@Au nanorod array with fast bacterial inactivation and excellent recyclability was reported.93%bacteria could be inactivated within 5 min ultra-sonication under indoor daylight,and the killing rate maintains above 90%after seven repeated using *** mechanism involves extracellular reactive oxygen species(ROS)generated from photocatalysis and piezoelectricity of nanorod array,intracellular ROS generation and decrease of adenosine-triphosphate(ATP)originated from electron transfer(ET)from bacteria to nanorod array,as well as mechanical effect from the nanorod,among which ET mechanism plays a major *** Schottky barrier from the hybrid interface not only enhances the ROS generation by promoting the charge transfer and carrier separation as well as light utilization,but also enables one-direction electron transfer from bacteria to nanorod *** resultant continuous electron loss breaks the energy metabolism and disturbs the redox equilibrium,leading to bacterial *** study demonstrates the great potential of hybrid structure in antibacterial applications and indicates ET as a novel effective antibacterial mechanism for semiconductor materials,which provides insights into the design of next-generation antibacterial materials.

关键词： Antibacterial Hybrid structure Zinc oxide nanorod Electron transfer Reactive oxygen species Microarrays Nanocomposites Semiconductors