Food systems are deeply affected by climate change and air pollution,while being key contributors to these environmental *** the complex interactions among food systems,climate change,and air pollution is crucial for ...
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Food systems are deeply affected by climate change and air pollution,while being key contributors to these environmental *** the complex interactions among food systems,climate change,and air pollution is crucial for mitigating climate change,improving air quality,and promoting the sustainable development of food ***,the literature lacks a comprehensive review of these interactions,particularly in the current phase of rapid development in the *** address this gap,this study systematically reviews recent research on the impacts of climate change and air pollution on food systems,as well as the greenhouse gas and air pollutant emissions from agri-food systems and their contribution to global climate change and air *** addition,this study summarizes various strategies for mitigation and adaptation,including adjustments in agricultural practices and food supply *** changes in food systems are urgently needed to enhance adaptability and reduce *** review offers a critical overview of current research on the interactions among food systems,climate change,and air pollution and highlights future research directions to support the transition to sustainable food systems.
Medical image registration can establish the spatial consistency of the corresponding anatomical structures between different medical images, which is important in medical image analysis. In recent years, with the rap...
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Accurate cross sections of neutron induced fission reactions are required in the design of advanced nuclear systems and the development of fission *** projection chambers(TPCs),with their track reconstruction and part...
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Accurate cross sections of neutron induced fission reactions are required in the design of advanced nuclear systems and the development of fission *** projection chambers(TPCs),with their track reconstruction and particle identification capabilities,are considered the best detectors for high-precision fission cross section *** TPC developed by the back-streaming white neutron source(Back-n)team of the China Spallation Neutron Source(CSNS)was used as the fission fragment detector in *** this study,the cross sections of the ^(232)Th(n,f)reaction at five neutron energies in the 4.50−5.40 MeV region were *** fission fragments and α particles were well identified using our TPC,which led to a higher detection efficiency of the fission fragments and smaller uncertainty of the measured cross *** is the first measurement of the ^(232)Th(n,f)reaction using a TPC for the detection of fission *** uncertainties less than 5%,our cross sections are consistent with the data in different evaluation libraries,including JENDL-4.0,ROSFOND-2010,CENDL-3.2,ENDF/B-VⅢ.0,and BROND-3.1,whose uncertainties can be reduced after future improvement of the measurement.
Developing electrocatalysts that exhibit both high activity and ammonia selectivity for nitrate reduction is a significant and demanding challenge,primarily due to the complex nature of the multiple-electron reduction...
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Developing electrocatalysts that exhibit both high activity and ammonia selectivity for nitrate reduction is a significant and demanding challenge,primarily due to the complex nature of the multiple-electron reduction process *** encouraging approach involves coupling highly active precious metals with transition metals to enhance catalytic performance through ***,we report a ruthenium-nickel alloy catalyst with nanosheets(Ru-Ni NSs)structure that achieves a remarkable ammonia Faradaic efficiency of approximately 95.93%,alongside a yield rate of up to 6.11 g·h^(−1)·cm^(−2).Moreover,the prepared Ru-Ni NSs exhibit exceptional stability during continuous nitrate reduction in a flow reactor for 100 h,maintaining a Faradaic efficiency of approximately 90%and an ammonia yield of 37.4 mg·L^(−1)·h^(−1)using 0.05 M nitrate alkaline *** studies reveal that the catalytic process follows a two-step pathway,in which HONO serves as a migration *** presence of a partially oxidized Ru(002)surface enhances the adsorption of nitrate and facilitates the release of the migration intermediate by adjusting the strength of the electrostatic and covalent interactions between the adsorbate and the surface,*** the other hand,the Ni(111)surface promotes the utilization of the migration intermediate and requires less energy for NH_(3)*** tandem process contributes to a high catalytic activity of Ru-Ni NSs towards nitrate reduction.
There are a wide variety of intelligence accelerators with promising performance and energy efficiency,deployed in a broad range of applications such as computer vision and speech ***,programming productivity hinders ...
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There are a wide variety of intelligence accelerators with promising performance and energy efficiency,deployed in a broad range of applications such as computer vision and speech ***,programming productivity hinders the deployment of deep learning *** low-level library invoked in the high-level deep learning framework which supports the end-to-end execution with a given model,is designed to reduce the programming burden on the intelligence ***,it is inflexible for developers to build a network model for every deep learning application,which probably brings unnecessary repetitive *** this paper,a flexible and efficient programming framework for deep learning accelerators,FlexPDA,is proposed,which provides more optimization opportunities than the low-level library and realizes quick transplantation of applications to intelligence accelerators for fast *** evaluate FlexPDA by using 10 representative operators selected from deep learning algorithms and an end-to-end *** experimental results validate the effectiveness of FlexPDA,which achieves an end-to-end performance improvement of 1.620x over the low-level library.
Text clustering is a critical step in text data analysis and has been extensively studied by the text mining community. Most existing text clustering algorithms are based on the bag-of-words model, which faces the hig...
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Mobile CrowdSensing (MCS) is a data sensing paradigm that recruits users carrying mobile terminals to collect data. As its variant, Sparse MCS has been further proposed for large-scale and fine-grained sensing task wi...
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Considering the problem that the optimal error dynamics can only converge at the terminal time,an impact angle/time constraint missile guidance law with finite-time convergence is designed in this paper,which is based...
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Considering the problem that the optimal error dynamics can only converge at the terminal time,an impact angle/time constraint missile guidance law with finite-time convergence is designed in this paper,which is based on the pure proportional navigation(PPN)guidance law and the fast terminal error dynamics(FTED)*** missile guidance model and FTED equation are given first,and the dynamic equation of impact angle/time error based on PPN is also ***,the guidance law is designed based on FTED,and the guidance error can converge to 0 in a finite ***,considering the field of view constraint,the guidance law is improved by using the saturation function mapping ***,a numerical simulation example is given to verify the effectiveness of the guidance law,which shows that the guidance law proposed in this paper can make the missile quickly adjust to the desired states in advance,and effectively relieve the overload saturation pressure of the actuator.
Carbon-based solid acids have been successfully employed as acidic catalysts for pollutant mitigation in *** fully tap the potentials of commercially viable carbons for the preparation of solid acids and enhance their...
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Carbon-based solid acids have been successfully employed as acidic catalysts for pollutant mitigation in *** fully tap the potentials of commercially viable carbons for the preparation of solid acids and enhance their catalytic performances is a challenging *** this work,three commercialized carbons including biochar,activated carbon and graphite were preprocessed(ball-milling,Hummer exfoliation,HNO3 soaking,and microwave heating in HNO_(3),etc.),sulfonated,and evaluated as solid-acid catalysts for tylosin ***-originated solid acid performed the best through a balling-milling preprocess,while biochar-originated solid acids behaved well under all preprocessing treatments,in which 40 mg L^(−1) of tylosin was mitigated within 8 min by 1 g L^(−1) of biochar-originated solid *** biochar solid acid through the ball-milling preprocess presented high total acidity and large amounts of-SO_(3)H groups,due to dramatically increased surface area and the rise of activation groups(hydroxyl,alkyl and alkoxy groups,etc.)facilitating electrophilic *** addition,decreased particle size and aromaticity and increased structural defects also *** calculation of average local ionization energy(ALIE)of condensed aromatic model molecules with substituted activation groups confirmed the promoting effects on sulfonation from strong to weak were 8.40-9.06 *** findings have deepened the knowledge in tuning carbon surface chemistry for better sulfonation,thus strengthening catalytic degradation of *** value of this study is in pulling a clear thread for maneuvering solid-acid catalysts using carbons,which holds a novel promise for rationally functionalizing biochar-based catalysts for the remediation of macrolide antibiotics in polluted water.
A typical gully sub-basin with a complex geomorphological form is used to do a model test of gravity erosion of loess by considering the sequence of slopes in a prototype gully creating a sequence of underlying surfac...
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A typical gully sub-basin with a complex geomorphological form is used to do a model test of gravity erosion of loess by considering the sequence of slopes in a prototype gully creating a sequence of underlying surface forms in the upper reaches. The results show that the runoff from heavy rainfall is the main external force for the erosion of loess, and also is an important influencing factor to stimulate and intensify the development of gravity erosion. The soil structure and the height of the critical surface have a direct impact on the possibility of gravity erosion. Spatially, the upper section of the drainage channel mainly experiences undercutting and headcut erosion, the middle section mainly experiences lateral erosion and gravity erosion, and the lower section alternately experiences sedimentation or alluvial erosion. Rainfall splash erosion produces a large amount of sand to yield high concentration mud flows in the middle and lower sections of the channel. Because of the mud flows the flood flow is obviously larger than the runoff volume formed by rainfall in a small watershed. The flood formed by high-intensity rainfall brings a large amount of sediment into the downstream rivers along the channel, indicating that under the condition that high-intensity rainfall on the Loess Plateau, lots sediment will enter the Yellow River, and the erosion deformation occurs on all slopes. Further the steep slope drainage flow causes undercutting and lateral erosion, and the soil body moves down along the slope under the action of gravity. The gully in the middle section still experience sediment washing in both depth and width,and the downstream gully continues to experiences sedimentation due to the reduction of the gradient,reflecting the adaptive adjustment of water flow and the boundary. Headcut erosion occurred on almost all slopes during different periods of rainfall, while gravity erosion mostly occurred on steep slope sections during periods of high-intensity
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