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Interplant communication:an emerging battlefield in plant-aphid-virus interactions

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Science China(Life Sciences) 2024年第5期67卷 1069-1071页

作者： Yunjing Wang qian Gong Yule liu MOE Key Laboratory of Bioinformatics and Center for Plant Biology School of Life SciencesTsinghua UniversityBeijing 100084China Tsinghua-Peking Center for Life Sciences Beijing 100084China

Plants constantly face threats from various organisms,including pathogens and *** the pathogens,plant viruses are obligate intracellular parasites that infect plants and cause serious crop yield losses.

关键词： plant Plants communication

Two Matrix Theorems Arising from Nilpotent Groups

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Algebra Colloquium 2024年第3期31卷 499-504页

作者： Jing zhao Heguo liu School of Mathematics and Statistics Hainan University Haikou 570228China

For a nilpotent group G without π-torsion,and x,y ∈ G,if x^(n)=y^(n) for a T-number n,then x=y;if x^(m)y^(n)=y^(n)x^(m) for n-numbers m,n,then xy=*** is a wellknown result in group *** this paper,we prove two analogous theorems on matrices,which have independence ***,let m be a given positive integer and A a complex square matrix satisfying that(i)all eigenvalues of A are nonnegative,and(i)rank A^(2)=rank A;then A has a unique m-th root X with rank X^(2)=rank X,all eigenvalues of X are nonnegative,and moreover there is a polynomial f(λ)with X=f(A).In addition,let A and B be complex n×n matrices with all eigenvalues nonnegative,and rank A^(2)=rank A,rank B^(2)=rank B;then(i)A=B when A^(r)=B^(r) for some positive integer r,and(i)AB=BA when A^(s)B^(t)=B^(t)A^(s) for two positive integers s and t.

关键词： nilpotent group root matrix Chinese remainder theorem

Quantifying China's iron and steel industry's CO2 emissions and environmental health burdens:A pathway to sustainable transformation

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Environmental Science and Ecotechnology 2024年第4期20卷 189-197页

作者： Weiling Wu qian Tang Wenbo Xue Xurong Shi Dadi zhao Zeyuan liu Xin liu Chunlai Jiang Gang Yan Jinnan Wang State Environmental Protection Key Laboratory of Environmental Pollution and Greenhouse Gases Co-control Chinese Academy of Environmental PlanningBeijing100041China Center of Air Quality Simulation and System Analysis Chinese Academy of Environmental PlanningBeijing100041China State Environmental Protection Key Laboratory of Environmental Planning and Policy Simulation Chinese Academy of Environmental PlanningBeijing100041China College of Environmental&Resource Sciences Zhejiang UniversityHangzhou310058China

Assessing the iron and steel industry's(ISI)impact on climate change and environmental health is vital,particularly in China,where this sector significantly influences air quality and CO_(2)*** is a lack of comprehensive analyses that consider the environmental and health burdens of manufacturing processes for ISI ***,we present an integrated emission inventory that encompasses air pollutants and CO_(2)emissions from 811 ISI enterprises and five key manufacturing processes in *** analysis shows that sintering is the primary source of air pollution in the *** contributes 71%of SO_(2),73%of NO_(x),and 54%of PM_(2.5)*** the other hand,81%of total CO_(2)emissions come from blast ***,the contributions of ISI have resulted in an increase of 3.6 mg m^(-3)in national population-weighted PM_(2.5)concentration,causing approximately 59,035 premature deaths in *** from Hebei,Jiangsu,Shandong,Shanxi,and Inner Mongolia provinces contributed to 48%of PM_(2.5)-related deaths in ***,the transportation of air pollutants across provincial borders highlights a concerning trend of environmental health *** on the research findings,it is crucial for ISI manufacturers to prioritize the removal of outdated production capacities and adopt energy-efficient and advanced techniques,along with ultra-low emission *** is particularly important for those manufacturers with substantial environmental *** transformative actions are essential in mitigating the environmental and health impacts in the affected regions.

关键词： Iron and steel industry CO_(2)emissions Air pollutants emissions Environmental health

A path planning algorithm for a crop monitoring fixed-wing unmanned aerial system

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Science China(Information Sciences) 2024年第08期67卷 5-23页

作者： Longhao qian Yi Lok LO Hugh Hong-tao liu Institute of Aerospace Studies University of Toronto Department of Mechanical Engineering The University of Hong Kong

With the growing demand for automation in agriculture, industries increasingly rely on drones to perform crop monitoring and surveillance. In this regard, fixed-wing unmanned aerial systems(UASs)are viable platforms for scanning a large crop field, given their payload capacity and range. To achieve maximum coverage without landing for battery replacement, an algorithm for producing a minimal required energy survey path is essential. Hence, an energy-aware coverage path planning algorithm is proposed *** constraints for a fixed-wing UAS to fly at low altitudes while achieving full coverage of the crop field are first analyzed. Then, the full path is decomposed into straight-line and U-turn primitives. Finally, an algorithm to calculate a combination of straight-line segments and U-turns is proposed to obtain the path with minimum required energy consumption. The genetic algorithm is used to efficiently determine the order of the straight-line paths to traverse. Case studies show that the proposed algorithm can produce planning results for a convex-polygon-shaped crop field.

关键词： path planning genetic algorithm energy minimization fixed-wing UAS aerial survey

Transforming liquid flow fuel cells to controllable reactors for highlyefficient oxidation of 5-hydroxymethylfurfural to 2, 5-furandicarboxylic acid at low temperature

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Journal of Energy Chemistry 2024年第3期90卷 621-631,I0014页

作者： Ye qiang Xi liu Denghao Ouyang zhao Jiang Xuebing zhao Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084China Institute of Applied Chemistry Department of Chemical EngineeringTsinghua UniversityBeijing 100084China School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'an 710049ShaanxiChina

Highly-efficient oxidation of 5-hydroxymethylfurtural(HMF) to 2,5-furandicarboxylic acid(FDCA) at low temperature with air as the oxidant is still ***,inspired by the respirato ry electron transport chain(ETC) of living cells mediated by electron carriers,we constructed artificial ETCs and transformed liquid flow fuel cells(LFFCs) to flexible reactors for efficient oxidation of HMF to produce FDCA under mild *** LFFC reactor employed an electrodeposition modified nickel foam as an anode to promote HMF oxidation and(VO_(2))_(2)SO_(4) as a cathode electron carrier to facilitate the electron transfer to *** reaction rate could be easily controlled by selecting the anode catalyst,adjusting the external loading and changing the cathodic electron carrier or oxidants.A maximal power density of 44.9 mW cm^(-2) at room temperature was achieved,while for FDCA production,short-circuit condition was preferred to achieve quick transfer of *** a single batch operation with 0.1 M initial HMF,FDCA yield reached 97.1%.By fed-batch operation,FDCA concentration reached 144.5 g L^(-1) with a total yield of 96%.Ni^(2+)/Ni^(3+) redox couple was the active species mediating the electron transfer,while both experimental and DFT calculation results indicated that HMFCA pathway was the preferred reaction mechanism.

关键词： 5-Hydroxymethylfurfural 2 5-Furandicarboxylic acid Electrodeposition Electron transport chain Liquid flow fuel cell

Monitoring and evaluation of the water quality of the Lower Neches River, Texas, USA

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Water Science and Engineering 2024年第1期17卷 21-32页

作者： Qin qian Mengjie He Frank Sun Xinyu liu Department of Civil and Environmental Engineering Lamar UniversityBeaumontTX 77710USA Department of Industry Engineering Lamar UniversityBeaumontTX 77710USA Department of Computer Science Lamar UniversityBeaumontTX 77710USA

Increasing bacteria levels in the Lower Neches River caused by Hurricane Harvey has been of a serious *** study is to analyze the historical water sampling measurements and real-time water quality data collected with wireless sensors to monitor and evaluate water quality under different hydrological and hydraulic *** statistical and Pearson correlation analysis on historical water samples determines that alkalinity,chloride,hardness,conductivity,and pH are highly correlated,and they decrease with increasing flow rate due to *** flow rate has positive correlations with Escherichia coli,total suspended solids,and turbidity,which demonstrates that runoff is one of the causes of the elevated bacteria and sediment loadings in the *** correlation between *** and turbidity indicates that turbidity greater than 45 nephelometric turbidity units in the Neches River can serve as a proxy for *** to indicate the bacterial outbreak.A series of statistical tools and an innovative two-layer data smoothing filter are developed to detect outliers,fill missing values,and filter spikes of the sensor *** correlation analysis on the sensor data illustrates that the elevated sediment/bacteria/algae in the river is either caused by the first flush rain and heavy rain events in December to March or practices of land use and land ***,utilizing sensor measurements along with rainfall and discharge data is recommended to monitor and evaluate water quality,then in turn to provide early alerts on water resources management decisions.

关键词： Water quality Pearson correlation analysis Lower Neches River YSI wireless sensors Non-point pollution

Temperature trends and its elevation-dependent warming over the Qilian Mountains

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Journal of Mountain Science 2024年第2期21卷 500-510页

作者： zhao Peng HE Zhibin MA Dengke WANG Wen qian Lihui School of Computer Science Huainan Normal UniversityHuainan 232038China Linze Inland River Basin Research Station Key Laboratory of Inland River Basin ScienceNorthwest Institute of Eco-Environment and ResourceChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

Understanding temperature variability especially elevation dependent warming(EDW)in high-elevation mountain regions is critical for assessing the impacts of climate change on water resources including glacier melt,degradation of soils,and active layer *** means that temperature is warming faster with the increase of *** this study,we used observed temperature data during 1979-2017 from 23 meteorological stations in the Qilian Mountains(QLM)to analyze temperature trend with Mann-Kendall(MK)test and Sen’s slope *** showed that the warming trends for the annual temperature followed the order of T_min>T_mean>T_max and with a shift both occurred in *** and summer temperature have a higher increasing trend than that in autumn and winter.T_mean shifts occurred in 1996 for spring and summer,in 1997 for autumn and winter.T_max shifts occurred in 1997 for spring and 1996 for summer.T_min shifts occurred in 1997 for spring,summer and winter as well as in 1999 for *** mean diurnal temperature range(DTR)shows a significant decreasing trend(-0.18°C/10a)from 1979 to *** mean DTR shows a significant decreasing trend(-0.26°C/10a)from 1979 to 2017 with a shift occurred in *** removing longitude and latitude factors,we can learn that the warming enhancement rate of average annual temperature is 0.0673°C/km/10a,indicating that the temperature warming trend is accelerating with the continuous increase of *** increase rate of elevation temperature is 0.0371°C/km/10a in spring,0.0457°C/km/10a in summer,0.0707°C/km/10a in autumn,and 0.0606°C/km/10a in winter,which indicates that there is a clear EDW in the *** main causes of warming in the Qilian Mountains are human activities,cloudiness,ice-snow feedback and El Nino phenomenon.

关键词： Climate change Qilian Mountains Warming rates DTR Elevation-dependent warming

Porous TiFe_(2) intermetallic compound fabricated via elemental powder reactive synthesis

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 764-772页

作者： qian zhao Zhenli He Yuehui He Yue Qiu Zhonghe Wang Yao Jiang State Key Laboratory of Powder Metallurgy Powder Metallurgy Research InstituteCentral South UniversityChangsha 410083China

Porous intermetallics show potential in the field of filtration and separation as well as in the field of ***,porous Ti Fe2intermetallics were fabricated by the reactive synthesis of elemental *** phase transformation and pore formation of porous TiFe2intermetallics were investigated,and its corrosion behavior and hydrogen evolution reaction(HER)performance in alkali solution were *** TiFe2intermetallics with porosity in the range of 34.4%-56.4%were synthesized by the diffusion reaction of Ti and Fe elements,and the pore formation of porous TiFe2intermetallic compound is the result of a combination of the bridging effect and the Kirkendall *** porous TiFe2samples exhibit better corrosion resistance compared with porous 316L stainless steel,which is related to the formation of uniform nanosheets on the surface that hinder further corrosion,and porous TiFe2electrode shows the overpotential of 220.6 and 295.6 mV at 10 and 100 mA·cm-2,suggesting a good catalytic *** synthesized porous Fe-based intermetallic has a controllable pore structure as well as excellent corrosion resistance,showing its potential in the field of filtration and separation.

关键词： TiFe2 intermetallic compound porous materials reactive synthesis corrosion behavior hydrogen evolution reaction

A deep reinforcement learning approach to gasoline blending real-time optimization under uncertainty

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Chinese Journal of Chemical Engineering 2024年第7期71卷 183-192页

作者： Zhiwei Zhu Minglei Yang Wangli He Renchu He Yunmeng zhao Feng qian Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

The gasoline inline blending process has widely used real-time optimization techniques to achieve optimization objectives,such as minimizing the cost of ***,the effectiveness of real-time optimization in gasoline blending relies on accurate blending models and is challenged by stochastic ***,we propose a real-time optimization algorithm based on the soft actor-critic(SAC)deep reinforcement learning strategy to optimize gasoline blending without relying on a single blending model and to be robust against *** approach constructs the environment using nonlinear blending models and feedstocks with *** algorithm incorporates the Lagrange multiplier and path constraints in reward design to manage sparse product *** abstracted states facilitate algorithm convergence,and the normalized action vector in each optimization period allows the agent to generalize to some extent across different target production *** these well-designed components,the algorithm based on the SAC outperforms real-time optimization methods based on either nonlinear or linear *** even demonstrates comparable performance with the time-horizon based real-time optimization method,which requires knowledge of uncertainty models,confirming its capability to handle uncertainty without accurate *** simulation illustrates a promising approach to free real-time optimization of the gasoline blending process from uncertainty models that are difficult to acquire in practice.

关键词： Deep reinforcement learning Gasoline blending Real-time optimization Petroleum Computer simulation Neural networks