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Natural Resources 2024年第3期15卷 61-68页

作者： Amadou Issoufou Abdourhimou Moussa Boubacar Habou Rabiou Soumana Idrissa Mahamane Ali Faculté des Sciences Agronomiques Université de Diffa Diffa Niger Institut National de la Recherche Agronomique du Niger Niamey Niger Faculté des Sciences et Techniques Université Abdou Moumouni de Niamey Niamey Niger

Information on the dynamics of savannah is important to a country's plan to overcome the problems of uncontrolled development and environmental hazards. Taking the reserve partielle de Dosso, Niger as the case study area, this paper analyzed the long-term land use land cover change from 2002 to 2022. Satellite images were processed by using Google Earth Engine (GEE). Therefore, four major land cover classes were identified based on spectral characteristics of Land sat, namely, built-up, vegetation, cropland, bare land and water. The result revealed that barren and built-up areas increased at the expense of vegetation and water. From the four major land use land cover the large area is covered by vegetation which comprises about 192963.5 hectares followed by cropland and water consisting of 32506.43 and 1596.4 hectares respectively. The built-up area gained substantial area (most) during the study period. The reduction in some of the land cover/uses underlines the dangerous trend of the pressure poised by population growth and the changing functionality. Land cover change is influenced by a variety of societal factors operating on several spatial and temporal levels. The area estimates and spatial distributions of the LULC classes produced from the current study will assist local authorities, managers, and other stakeholders in decision-making and planning regarding forest land cover and uses.

关键词： Land Use/Cover Change detection Classification Dosso

Electrochemical Analysis of Zirconiumin Aqueous and Organic Media

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American Journal of Analytical Chemistry 2024年第2期15卷 99-118页

作者： Paul Mendy Démo Koita Theodore Tzedakis Cheikhou Kane Codou Guèye Mar-Diop Ecole Supérieure Polytechnique Université Cheikh Anta DIOP Dakar Sénégal Laboratoire de Génie Chimique Université de Toulouse III—Paul Sabatier Toulouse France

For the challenging nature of the zirconium environment analysis, this study consists to analyze the electrochemical behavior of Zirconium in both aqueous and organic media. To that end first the electrolytic media was selected on the basis of the Pourbaix potential-pH diagram, which provides informations on the predominance of Zr(IV) ion and Zr in aqueous media. In aqueous media, analyzes were first carried out in acidic media then in basic media. Studies have thus revealed that the acidic environment is not favourable for the electrochemical analysis of zirconium. Voltammograms obtained in an acidic environment show no zirconium detection signal;this is due to the strong presence of H+ ions in the solution. We have also observed in acidic media the phenomenon of passivation of the electrode surface. In aqueous alkaline media (pH = 13), we have drawn in reduction several Intensity-Potential curves by fixingsome technical parameterslike scanning speed, rotation speed of the electrode. The obtained voltammograms show cathodic waves, starting from -1.5 V/DHW and attributed to the reduction of Zr (IV) to Zr (0). The last phase of this study focused on the electrochemical analysis of zirconium in an organic media. In this media, several intensity-potential curves were plotted in reduction and in cyclic voltammetry with various parameters. Through several reduction analysis, the Zr (IV) was reduced to Zr (0) to the potential of -1.5 V/DHW. The electrochemical analysis of zirconium in organic media seems globally easier to achieve thanks to its large solvent window (i.e. dimethylformamide (DMF) solvent window > 6 V).

关键词： Zirconium Electrochemical Reduction Cyclic Voltammetry Voltammogram Dymethylformamide

Vaccination effect on a stochastic epidemic model with healing and relapse

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International Journal of Biomathematics 2024年第1期17卷 29-59页

作者： M.M.Abdeslami L.Basri M.El Fatini I.Sekkak R.Taki Laboratory of Partial Differential Equations Spectral Algebra and Geometry department of Mathematics Faculty of Sciences Ibn Tofail UniversityBP 133KénitraMorocco Centre de Recherche en Sante Publique Montréal(Québec)H3N 1X9 Canada Departement de Medecine Sociale et Preventive Ecole de SantéPublique de I'Universitéde Montreal 101Avenue du ParcMontréal(Quebec)H3N 1X9Canada EST Sidi Bennour Chouaib Doukkali UniversityEl JadidaMorocco

In this work,we consider a stochastic epidemic model with vaccination,healing and *** prove the existence and the uniqueness of the positive *** establish sufficient conditions for the extinction and the persistence in mean of the stochastic ***,we also establish sufficient conditions for the existence of ergodic stationary distribution to the model,which reveals that the infectious disease will *** graphical illustrations of the approximate solutions of the stochastic epidemic model have been performed.

关键词： Stochastic epidemic model with relapse and healing vaccination extinction persistence in mean Markov semigroup stationary distribution

Synchronized off-harmonic probe laser with highly variable pulse duration for laser-plasma interaction experiments

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High Power Laser Science and Engineering 2024年第1期12卷 99-107页

作者： J.Hornung Y.Zobus H.Lorenté C.Brabetz B.Zielbauer V.Bagnoud GSI Helmholtzzentrum für Schwerionenforschung GmbH DarmstadtGermany Institut d’Optique UniversitéParis-SaclayPalaiseauFrance Institut für Angewandte Physik Technische Universität DarmstadtDarmstadtGermany

This paper presents the development and experimental utilization of a synchronized off-harmonic laser system designed as a probe for ultra-intense laser±plasma interaction experiments. The system exhibits a novel seed-generation design,allowing for a variable pulse duration spanning over more than three orders of magnitude, from 3.45 picoseconds to 10 nanoseconds. This makes it suitable for various plasma diagnostics and visualization techniques. In a side-view configuration, the laser was employed for interferometry and streaked shadowgraphy of a laser-induced plasma while successfully suppressing the self-emission background of the laser±plasma interaction, resulting in a signal-to-self-emission ratio of 110 for this setup. These properties enable the probe to yield valuable insights into the plasma dynamics and interactions at the PHELIX facility and to be deployed at various laser facilities due to its easy-to-implement design.

关键词： interferometry laser-plasma interaction off-harmonic probe laser streaked shadowgraphy

Electrifying Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ) for focalized heating in oxygen transport membranes

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Journal of Energy Chemistry 2024年第4期91卷 99-110页

作者： Marwan Laqdiem Julio García-Fayos Laura Almar Alfonso J.Carrillo Álvaro Represa JoséM.López Nieto Sonia Escolástico David Catalán-Martinez Jose M.Serra Instituto de Tecnología Química(universitat Politècnica de València–Consejo Superior de Investigaciones Científicas) Av.Los Naranjos s/nE-46022 ValenciaSpain

Industry decarbonization requires the development of highly efficient and flexible technologies relying on renewable energy resources,especially biomass and solar/wind *** the case of pure oxygen production,oxygen transport membranes(OTMs)appear as an alternative technology for the cryogenic distillation of air,the industrially-established process of producing ***,OTMs could provide oxygen from different sources(air,water,CO_(2),etc.),and they are more flexible in adapting to current processes,producing oxygen at 700^(-1)000℃.Furthermore,OTMs can be integrated into catalytic membrane reactors,providing new pathways for different *** first part of this study was focused on electrification on a traditional OTM material(Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)),imposing different electric currents/voltages along a capillary *** to the emerging Joule effect,the membrane-surface temperature and the associated O_(2) permeation flux could be ***,the OTM is electrically and locally heated and reaches 900℃on the surface,whereas the surrounding of the membrane was maintained at 650℃.The O_(2)permeation flux reached for the electrified membranes was~3.7 NmL min^(-1)cm^(-2),corresponding to the flux obtained with an OTM non-electrified at 900℃.The influence of depositing a porous Ce_(0.8)Tb_(0.2)O_(2-δ) catalytic/protective layer on the outer membrane surface revealed that lower surface temperatures(830℃)were detected at the same imposed electric ***,the electrification concept was demonstrated in a catalytic membrane reactor(CMR)where the oxidative dehydrogenation of ethane(ODHE)was carried *** reaction is very sensitive to temperature,and here,we demonstrate an improvement of the ethylene yield by reaching moderate temperatures in the reaction chamber while the O_(2) injection into the reaction can be easily fine-tuned.

关键词： Oxygen permeation Oxidative dehydrogenation of ethane Oxygen transport membranes Joule effect Mixed ionic-electronic conductors Catalytic membrane reactors

All-electron basis sets for H to Xe specific for ZORA calculations:Applications in atoms and molecules

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Chinese Physics B 2024年第8期33卷 238-246页

作者： C.S.Gomes F.E.Jorge A.Canal Neto departamento de Fisica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil departamento de Fisica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA *** set was augmented with diffuse functions to describe electrons farther away from the nuclei *** the ZORA-CCSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were *** addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular *** atomization energies,a similar observation emerges when considering spin-orbit *** the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.

关键词： QZP-ZORA and AQZP-ZORA basis sets elements from H to Xe CCSD(T)method atomic and molecular properties

Litter production and leaf nutrient concentration and remobilization in response to climate seasonality in the central Amazon

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Journal of Forestry Research 2024年第3期35卷 131-141页

作者： Ricardo Antonio Marenco Saul Alfredo Antezana-Vera Daniela Pereira Dias Luiz Antonio Candido Instituto Nacional de Pesquisas da Amazonia Coordenagao de Uso da Terra e Mudanca ClimaticaAv.Andre Araujo 2936ManausAM69067-375Brazil Programa de pos-Graduagao em Agricultura no Tropico Umido Instituto Nacional de Pesquisas da Amazonia-INPAManausAMBrazil Unidade Academica de Ciencias Agrarias Universidade Federal de JataiBR 364km 195JataiGO 75801-615Brazil

Litterfall is the largest source of nutrients to for-est soils of tropical ***,variability in lit-terfall production,nutrient remobilization,and changes in leaf nutrient concentration with climate seasonality remain largely unknown for the central *** study meas-ured litterfall production,leaf nutrient remobilization,and leaf area index on a forest plateau in the central *** was measured at monthly intervals during 2014,while nitrogen,phosphorus,potassium,calcium and mag-nesium concentrations of leaf litter and canopy leaves were measured in the dry and rainy seasons,and remobilization rates *** area index was also recorded in the dry and rainy *** litterfall varied from 33.2(in the rainy season)to 87.6 g m^(-2) in the dry season,while leaf area index increased slightly in the rainy *** seasonality had no effect on concentrations of nitrogen,calcium,and magnesium,whereas phosphorous and potassium responded to rainfall seasonality *** phosphorous increased,potassium decreased during the dry *** seasons,nitrogen,potassium,and phosphorous decreased in leaf litter;calcium increased in leaf litter,while magnesium remained unaffected with leaf ***,the five nutrients had similar remobilization rates over the *** absence of climate seasonality on nutrient remobilization suggests that the current length of the dry season does not alter nutrient remobilization rates but this may change as dry periods become more prolonged in the future due to climate change.

关键词： Throughfall Nutrient cycling Climatic seasonality Leaf mass per area

New Fusion Approach of Spatial and Channel Attention for Semantic Segmentation of Very High Spatial Resolution Remote Sensing Images

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Open Journal of Applied Sciences 2024年第2期14卷 288-319页

作者： Armand Kodjo Atiampo Gokou Hervé Fabrice Diédié Unité de Recherche et d’Expertise du Numerique (UREN) Université Virtuelle de Céte d’Ivoire Abidjan Ivory Coast Laboratoire de Mathématiques et Informatique Université Peleforo Gon Coulibaly Korhogo Ivory Coast

The semantic segmentation of very high spatial resolution remote sensing images is difficult due to the complexity of interpreting the interactions between the objects in the scene. Indeed, effective segmentation requires considering spatial local context and long-term dependencies. To address this problem, the proposed approach is inspired by the MAC-UNet network which is an extension of U-Net, densely connected combined with channel attention. The advantages of this solution are as follows: 4) The new model introduces a new attention called propagate attention to build an attention-based encoder. 2) The fusion of multi-scale information is achieved by a weighted linear combination of the attentions whose coefficients are learned during the training phase. 3) Introducing in the decoder, the Spatial-Channel-Global-Local block which is an attention layer that uniquely combines channel attention and spatial attention locally and globally. The performances of the model are evaluated on 2 datasets WHDLD and DLRSD and show results of mean intersection over union (mIoU) index in progress between 1.54% and 10.47% for DLRSD and between 1.04% and 4.37% for WHDLD compared with the most efficient algorithms with attention mechanisms like MAU-Net and transformers like TMNet.

关键词： Spatial-Channel Attention Super-Token Segmentation Self-Attention Vision Transformer

Tribologically induced nanostructural evolution of carbon materials: A new perspective

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Friction 2024年第1期12卷 144-163页

作者： Guilherme Oliveira NEVES Nicolás ARAYA Diego Berti SALVARO Thiago de Souza LAMIM Renan Oss GIACOMELLI Cristiano BINdeR Aloisio Nelmo KLEIN JoséDaniel Biasoli de MELLO Laboratório de Materiais Universidade Federal de Santa CatarinaSanta Catarina 88040-900Brazil departamento de Ingeniería Mecánica Facultad de IngenieríaUniversidad del Bío-BíoConcepcion 4070-386Chile Universidad de Concepción Concepcion 4070-386Chile SENAI Innovation Institute for Laser Processing Santa Catarina 89218-153Brazil Universidade Federal de Uberlândia Minas Gerais 38408-100Brazil

Carbon-based solid lubricants are excellent options to reduce friction and wear,especially with the carbon capability to adopt different allotropes *** the macroscale,these materials are sheared on the contact along with debris and contaminants to form tribolayers that govern the tribosystem *** a recently developed advanced Raman analysis on the tribolayers,it was possible to quantify the contactinduced defects in the crystalline structure of a wide range of allotropes of carbon-based solid lubricants,from graphite and carbide-derived carbon particles to multi-layer graphene and carbon *** addition,these materials were tested under various dry sliding conditions,with different geometries,topographies,and solid-lubricant application *** of the initial tribosystem conditions and allotrope level of atomic ordering,there is a remarkable trend of increasing the point and line defects density until a specific saturation limit in the same order of magnitude for all the materials tested.

关键词： carbon nanostructures tribology Raman spectroscopy defects quantification tribolayer solid lubrication

Exploring the effects of dietary inulin in rainbow trout fed a high‑starch,100%plant‑based diet

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Journal of Animal Science and Biotechnology 2024年第2期15卷 713-732页

作者： Raphaël defaix Jep Lokesh Laura Frohn Mickael Le Bechec Thierry Pigot Vincent Veron Anne Surget Sandra Biasutti Frederic Terrier Sandrine Skiba-Cassy Jerome Roy Stephane Panserat Karine Ricaud universite de Pau Et des Pays de L’Adour E2S UPPAINRAENUMEASaint‑Pee‑Sur‑NivelleFrance universite de Pau Et des Pays de L’Adour E2S UPPACNRSIMT Mines AlesIPREMPauFrance universite de Pau Et des Pays de L’Adour E2S UPPAIUT des Pays de l’AdourDepartement Genie BiologiqueMont de MarsanFrance.

Background High dietary carbohydrates can spare protein in rainbow trout(Oncorhynchus mykiss)but may affect growth and ***,a prebiotic,could have nutritional and metabolic effects,along with anti-inflammatory properties in teleosts,improving growth and *** tested this hypothesis in rainbow trout by feeding them a 100%plant-based diet,which is a viable alternative to fishmeal and fish oil in aquaculture *** a two-factor design,we examined the impact of inulin(2%)as well as the variation in the carbohydrates(CHO)/plant protein ratio on rainbow *** assessed the influence of these factors on zootechnical parameters,plasma metabolites,gut microbiota,production of short-chain fatty acids and lactic acid,as well as the expression of free-fatty acid receptor genes in the mid-intestine,intermediary liver metabolism,and immune markers in a 12-week feeding *** The use of 2%inulin did not significantly change the fish intestinal microbiota,but interestingly,the high CHO/protein ratio group showed a change in intestinal microbiota and in particular the beta diversity,with 21 bacterial genera affected,including Ralstonia,Bacillus,and 11 lactic-acid producing *** were higher levels of butyric,and valeric acid in groups fed with high CHO/protein diet but not with *** high CHO/protein group showed a decrease in the expression of pro-inflammatory cytokines(il1b,il8,and tnfa)in liver and a lower expression of the genes coding for tight-junction proteins in mid-intestine(tjp1a and tjp3).However,the 2%inulin did not modify the expression of plasma immune ***,inulin induced a negative effect on rainbow trout growth performance irrespective of the dietary *** With a 100%plant-based diet,inclusion of high levels of carbohydrates could be a promising way for fish nutrition in aquaculture through a protein sparing effect whereas the supplementation of 2%inulin does not appear to improve the use of CHO wh

关键词： Aquaculture Fish nutrition Gut microbiota Immune markers Intermediary metabolism Inulin Prebiotic Rainbow trout Short-chain fatty acids