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A field parcel-oriented approach to evaluate the crop cover-management factor and time-distributed erosion risk in Europe

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International Soil and Water Conservation Research 2023年第1期11卷 43-59页

作者： francis Matthews Gert Verstraeten Pasquale Borrelli Panos Panagos European Commission Joint Research Centre(JRC)IspraItaly Department of Earth and Environmental Sciences KU LeuvenBelgium Department of Science Roma Tre University00146RomeItaly

the crop cover-management(C-)factor in arable landscapes describes the soil erosion susceptibility associated with seasonally cultivated *** informatic and computational limitations have led many modelling studies to prescribe C-factor values and assume spatial and temporal ***,the multiple influencing factors ranging from parcel-scale crop cultivation and management to regional-scale rainfall regimes motivates new methods to capture this variation when identifying at-risk ***,we define a multi-component method to derive the C-factor by associating time series of canopy and residue surface cover from Sentinel-2 and climate-specific rainfall erosivity with Integrated Administration and Control System(IACS)field parcel data from European Union member states.A scalable and standardised method is emphasised to increase the future interoperability and inter-comparability of soil erosion modelling studies deploying the ***,field parcel simu-lation units with associated crop declarations provide a new reference scale to link predictions of soil erosion risk with specific management decisions and declarations by *** implementing the method on a homogenised subsample of 8600 field parcels covering available IACS regions,several key findings are outlined:1)time series information provides new opportunities to predict the time-criticality of erosion in specific crop cultivations,2)the varying(a-)synchronicity between seasonal crop canopy cover and heavy rainstorms means that spatial variability is inherent within the C-factor across Europe,and 3)the addition of agricultural management practices(*** practice de-scriptions)to open-access IACS repositories can facilitate more comprehensive evaluations of the C-factor and soil erosion risk.

关键词： C-factor Soil erosion Modelling Remote sensing Crop-phenology IACS data Soil conservation Europe

Disinfection byproduct regulatory compliance surrogates and bromide-associated risk

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Journal of Environmental Sciences 2017年第8期29卷 191-207页

作者： Chelsea Kolb Royce A.francis Jeanne M.VanBriesen Department of Ciuil and Environmental Engineering Carnegie Mellon Uniuersity Pittsburgh PA 15213 USA Department of Engineering Management and Systems Engineering The George Washington University Washington DC 20052 USA Department of Engineering and Public Policy Carnegie Mellon University Pittsburgh PA 15213 USA

Natural and anthropogenic factors can alter bromide concentrations in drinking water sources. Increasing source water bromide concentrations increases the formation and alters the speciation of disinfection byproducts（DBPs） formed during drinking water *** DBPs are more toxic than their chlorinated analogs, and thus have a greater impact on human health. However, DBPs are regulated based on the mass sum of DBPs within a given class（e.g., trihalomethanes and haloacetic acids）, not based on species-specific risk or extent of bromine incorporation. the regulated surrogate measures are intended to protect against not only the species they directly represent, but also against unregulated DBPs that are not routinely measured. Surrogates that do not incorporate effects of increasing bromide may not adequately capture human health risk associated with drinking water when source water bromide is elevated. the present study analyzes trihalomethanes（tHMs）, measured as ttHM,with varying source water bromide concentrations, and assesses its correlation with brominated tHM, ttHM risk and species-specific tHM concentrations and associated *** potential surrogates are evaluated to assess their ability to capture tHM risk under different source water bromide concentration conditions. the results of the present study indicate that ttHM does not adequately capture risk of the regulated species when source water bromide concentrations are elevated, and thus would also likely be an inadequate surrogate for many unregulated brominated species. Alternative surrogate measures,including tHM3 and the bromodichloromethane concentration, are more robust surrogates for species-specific tHM risk at varying source water bromide concentrations.

关键词： Disinfection byproducts Bromide Disinfection byproduct regulation trihalomethanes Disinfection byproduct risk

Local measurement of terahertz field-induced second harmonic generation in plasma filaments

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Frontiers of Optoelectronics 2023年第4期16卷 135-178页

作者： Kareem J.Garriga francis Xi‑Cheng Zhang the Institute of Optics University of RochesterRochesterNY 14627USA

the concept of terahertz Field-Induced Second Harmonic(tFISH)Generation is revisited to introduce a single-shot detection scheme based on third order *** specifcally on the further development of tHz plasma-based sources,we begin our research by reimagining the tFISH system to serve as a direct plasma *** this work,an optical probe beam is used to mix directly with the strong ponderomotive current associated with laser-induced ionization.A four-wave mixing(FWM)process then generates a strong second-harmonic optical wave because of the mixing of the probe beam with the nonlinear current components oscillating at tHz *** observed conversion efciency is high enough that for the frst time,the tFISH signal appears visible to the human *** perform spectral,spatial,and temporal analysis on the detected second-harmonic frequency and show its direct relationship to the nonlinear ***,a method to detect incoherent and coherent tHz inside plasma flaments is devised using spatio-temporal *** single-shot detection confgurations are theoretically described using a combination of expanded FWM models with Kostenbauder and Gaussian *** show that the retrieved temporal traces for tHz radiation from single-and twocolor laser-induced air-plasma sources match theoretical descriptions very *** temporal resolution is shown with a detection bandwidth limited only by the spatial extent of the probe laser *** detection bandwidth and temporal characterization is shown for tHz radiation confned to under-dense plasma flaments induced bythe relativistic intensity limit.

关键词： terahertz detection-Plasma characterization-Spectral characterization Single-shot detection

Recent advances in acoustofluidic separation technology in biology

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Microsystems & Nanoengineering 2022年第5期8卷 1-16页

作者： Yanping Fan Xuan Wang Jiaqi Ren francis Lin Jiandong Wu School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China Institute of Biomedical and Health Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Department of Physics and Astronomy University of ManitobaWinnipegMB R3T 2N2Canada

Acoustofluidic separation of cells and particles is an emerging technology that integrates acoustics and *** the last decade,this technology has attracted significant attention due to its biocompatible,contactless,and labelfree *** has been widely validated in the separation of cells and submicron bioparticles and shows great potential in different biological and biomedical *** review first introduces the theories and mechanisms of acoustofluidic ***,various applications of this technology in the separation of biological particles such as cells,viruses,biomolecules,and exosomes are ***,we discuss the challenges and future prospects of this field.

关键词： fluid separation acoustics

Fiber and colorectal diseases: Separating fact from fiction

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World Journal of Gastroenterology 2007年第31期13卷 4161-4167页

作者： Kok-Yang tan francis Seow-Choen Department of Surgery Alexandra Hospital Singapore Seow-Choen Colorectal Centre Pte Ltd Singapore

Whilst fruits and vegetables are an essential part of our dietary intake, the role of fiber in the prevention of colorectal diseases remains controversial. the main feature of a high-fiber diet is its poor digestibility. Soluble fiber like pectins, guar and ispaghula produce viscous solutions in the gastrointestinal tract delaying small bowel absorption and transit. Insoluble fiber, on the other hand, pass largely unaltered through the gut. the more fiber is ingested, the more stools will have to be passed. Fermentation in the intestines results in build up of large amounts of gases in the colon. this article reviews the physiology of ingestion of fiber and defecation. It also looks into the impact of dietary fiber on various colorectal diseases. A strong case cannot be made for a protective effect of dietary fiber against colorectal polyp or cancer. Neither has fiber been found to be useful in chronic constipation and irritable bowel syndrome. It is also not useful in the treatment of perianal conditions. the diverticulosis theory should also be challenged. the authors urge clinicians to keep an open mind about fiber. One must be aware of the truths and myths about fiber before recommending it.

关键词： Fiber Physiology Colorectal cancer Constipation Irritable bowel syndrome Diverticulosis Hemorrhoids

Synthesis of nanostructured zinc oxide and its composite with carbon dots for DSSCs applications using flexible electrode

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Materials Reports(Energy) 2024年第3期4卷 77-83页

作者： Habtamu Fekadu Etefa francis Birhanu Dejene Department of Physics Walter Sisulu UniversityPrivate Bag X-1Mthatha5117South Africa

ZnO nanowires(ZnO NWs),ZnO nanoparticles(ZnO NPs)and carbon dots(C-dots)were synthesized by hydrothermal,sol-gel and hydrothermal methods *** were also characterized and applied for dye sensitized solar cells(DSSCs).the effects of C-dots on ZnO NWs and ZnO NPs have been *** C-dots were used at a mole ratio of citric acid(CA)to ethylene diamine(EDA)of 1:*** C-dots were found to enhance the performance of the flexible electrode *** the addition of C-dots,the power conversion efficiency(PCE)of ZnO NPs was boosted to be two times higher than that of ZnO NPs DSSCs without ***,the ultraviolet(UV)-band revealed a blue shift,resulting in a lower band gap and a reduced charge transfer resistance,which can enhance the PCE of *** loaded quantity on the flexible electrode substrate made of polyethylene terephthalate(PEt)was optimized(50 mg).For DSSCs,the PEt flexible electrode conductive polymer has produced positive *** ZnO NWs and ZnO NWs@C-dots,the PCE values were 1.45%and 4.25%;while for ZnO NPs and ZnO NPs@C-dots,they were 2.34%and 5.81%,*** work achieved remarkable and competitive performance when compared to solid(indium tin oxides/glass)-based substrate.

关键词： ZnO NWs@C-dots ZnO NPs@C-dots PEt DSSCs Flexible electrode

Deterministic approaches for noncoherent communicationswith chaotic carriers

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Journal of Systems Engineering and Electronics 2005年第2期16卷 253-257页

作者： LiuXiongying QiuShuisheng francis.C.M.Lau CollegeofElectronicandInformationEngineering SouthChinaUniversityofTechnologyGuangzhou510640P.R.China DepartmentofElectronicandInformationEngineering HongkongPolytechnicUniversityHongkongP.R.China

two problems are proposed. the first one is the noise decontamination of chaotic carriers using a deterministic approach to reconstruct pseudo trajectories, the second is the design of communications schemes with chaotic carriers. After presenting our deterministic noise decontamination algorithm, conventional chaos shift keying (CSK) communication system is applied. the difference of Euclidean distance between noisy trajectory and decontaminated trajectory in phase space could be utilized to non-coherently detect the sent symbol simply and effectively. It is shown that this detection method can achieve the bit error rate performance comparable to other non-coherent systems.

关键词： gradient descent reconstruction chaotic communications noncoherent detection.

Impact of a Phosphate Amendment on the Environmental Availability and Phytoavailability of Cd and Pb in Moderately and Highly Carbonated Kitchen Garden Soils

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Pedosphere 2017年第3期27卷 588-605页

作者： Christophe WAtERLOt Christelle PRUVOt Franck MAROt francis DOUAY Yncréa Hauts-de-France Laboratoire Génie Civil et géo Environnement (LGCgE) Agence De l’Environnement et de la Matrise de l’Energie (ADEME) Direction Villes et Territoires Durables Services Friches Urbaines et Sites Pollués

the behaviour of metals mainly depends on soil p H, carbonate contents and contamination level, which should be considered for the management of contaminated soils. In this study, kitchen garden topsoils(0–25 cm) were sampled from the area around three smelters in France, with different Cd and Pb contamination levels. Effect of a phosphate amendment(a mixture of diammonium phosphate and hydroxyapatite) on the environmental availability and phytoavailability of Cd and Pb was evaluated by different chemical extractions and cultivating lettuce(Lactuca sativa L.), respectively. Changes in the distribution of Cd and Pb were found in most contaminated soils after phosphate amendment. An increase of Cd and Pb in the residual phase was highlighted in almost all carbonated contaminated soils, whereas a decrease of Pb in the exchangeable, water and acid-soluble phase was observed in most contaminated soils with the lowest carbonate contents. the concentrations of extractable Cd and Pb using calcium chloride and acetic and citric acids generally decreased after the soil amendment. Lettuces grown on amended soils were acceptable for human consumption as regard to Pb concentration. In contrast, some lettuces were unacceptable for human consumption, since the concentrations of Cd in the leaves were higher than the European legislation limit. Surprisingly, in carbonated soils with very low concentration of Cd, the Cd concentrations in lettuce reached up to the European legislation limit, making the lettuce unacceptable for human *** study highlighted the fact that the total metal concentration in soils does not always allow to predict the metal accumulation in the edible parts of vegetables in order to make a judgement about their acceptability or unacceptability for human consumption.

关键词： chemical amendment contamination immobilisation lettuce metal urban soil

Landfill Site Suitability Assessment Using Geographic Information System (GIS) and Analytic Hierarchy Process (AHP) in Butuan City, Philippines

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Journal of Environmental & Earth Sciences 2023年第1期5卷 95-107页

作者： francis Jhun t.Macalam Kaleb P.Arreza Angelica t.Magpantay Kristine Y.Rabaño Department of Environmental Science and technology College of Science and MathematicsUniversity of Science and Technology of Southern PhilippinesCagayan de Oro Campus9000Philippines Department of Environmental Science College of Forestry and Environmental StudiesMindanao State University9023Philippines Interdisciplinary Studies Center for Integrated Natural Resources and Environment Management College of Forestry and Natural ResourcesUniversity of the Philippines Los BañosLaguna4031Philippines School of Environmental Science and Management University of the Philippines Los BaňosLaguna4031Philippines

Landfilling is one of the most effective and responsible ways to dispose of municipal solid waste(MSW).Identifying landfill sites,however,is a challenging and complex undertaking because it depends on social,environmental,technical,economic,and legal *** study aims to map the optimal sites that were environmentally suitable for locating a landfill site in Butuan City,*** reference to the policy requirements from DENR Section I,Landfill Site Identification Criteria and Screening Guidelines of National Solid Waste Management Commission,the integration of a Geographic Information System(GIS)model builder and Analytical Hierarchy Process(AHP)has been used in this study to address the aforementioned challenges related to the landfill site suitability *** on the generated sanitary landfill suitability map,results showed that Barangay tungao(1131.42967 ha)and Florida(518.48 ha)were able to meet and consider the three(3)main components,namely economic,environmental,and physical criteria,and are highly suitable as landfill site locations in Butuan *** is recommended that there will conduct a geotechnical evaluation,involving rigorous geological and hydrogeological assessment employing a combination of site investigation and laboratory *** addition,additional specific social,ecological,climatic,and economic factors need to be considered(*** impact on humans,flora,fauna,soil,water,air,climate,and landscape).

关键词： Geographic information system Sanitary landfill Analytic hierarchy process Butuan City Site suitability