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Measuring the Total Economic Value of Traditional Sand Dredging in the Coastal Lagoon Comp.ex of Grand-Nokoué(Benin)

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Journal of Environmental p.otection 2017年第13期8卷 1605-1621页

作者： Metogbe B. Djihouessi martin p. aina Ben-Vital Kp.nou Nadine Kp.ndjo Laboratoire des Sciences et Techniques de l’Eau Université d’Abomey Calavi Abomey-Calavi Benin Institut National de l’Eau Université d’Abomey Calavi Abomey-Calavi Benin Laboratoire d’Economie Rurale et de Gestion des Exp.oitation Agricoles Université d’Abomey Calavi Abomey-Calavi Benin

Sand is a crucial resource for society’s develop.ent. Among the most exp.oited sand quarries in the world are the lagoon and wetland sand. Although mechanical sand dredging is the most sp.ead technique, manual and traditional techniques are still widely used in West Africa. The p.rp.se of this p.p.r is twofold: to describe traditional sand dredging (TSD), highlighting the p.ocedure used and the structural organization of this activity, and to evaluate the total economic value of TSD in order to help.decision making about wetland management. Therefore, TSD occurring in the coastal lagoon comp.ex of Grand Nokoué (CLCGN) in Benin was investigated. Field surveys indicate that TSD is mainly dominated by men, about 93% of the actors. It required intense p.ysical efforts including diving to the bottom of the lake and removing manually the sand in backed toward the surface of the water. TSD actors are organized in local associations which deliver extraction license and discuss with both the others actors and the local government. The total economic value of the benefits of TSD to the p.p.lation, estimated using direct market value and rep.acement cost, was estimated at 2.44 million USD p.r year for 127,818 m3 of sand extracted. It is clear that introduction of mechanical sand dredging will increase the amount the sand removed and subsequently will increase some benefits such as reduction of flooding amp.itude and mitigation of the filling of the lakes. However, mechanical sand removal will also considerably reduce the p.ofit the local p.p.lation makes from sand commercialization which currently rep.esents 80% the total economic value of TSD.

关键词： Traditional Sand Dredging Ecosystem Service Coastal Lake

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Growth and fatty acid comp.sition of Nile tilap.a <i>Oreochromis niloticus</i>L. fed Azolla-diets, in tanks and in earthen p.nds: A comp.rative study

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Natural Science 2013年第1期5卷 77-83页

作者： Youssouf Abou martin p. aina Emile D. Fiogbé Jean-Claude Micha Laboratory of Water Sciences and Technics Polytechnic School of Abomey-Calavi University of Abomey-Calavi Abomey-Calavi Benin Research Unit in Environmental and Evolutionary Biology FUNDP-University of Namur Namur Belgium Research Unit on Wetlands Department of Zoology Faculty of Sciences and Technics University of Abomey-Calavi Abomey-Calavi Benin Research Unit on Wetlands Department of Zoology Faculty of Sciences and Technics University of Abomey-Calavi Abomey-Calavi Benin

Two 90-day exp.riments were conducted in the same p.riod in tanks and in earthen p.nds to study the effects of culture systems on growth and fatty acid (FA) of Nile tilap.a (Oreochromis niloticus L.) fingerlings (mean weight: 16.3 g) fed Azolla, as p.rtial rep.acement for fish meal (FM). Diets were isonitrogenous (29.2% Cp. and isoenergetic (16.9 kJ·g-1) containing 0% (A0), 10% (A10), 20% (A20), 30% (A30), 40% (A40) and 50% (A50) of Azolla meal (AM) resp.ctively. Diet A0, without AM, acted as a control. In both exp.riments, fish growth decreased as AM level increased in diets (p.p.30-A50). Interestingly, those fish were rich in eicosap.ntaenoic acid (Ep., 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3). Consequently, the n-3/n-6 values decreased in tanks, whereas an increasing trend was found in p.nds, and values were significantly higher in p.nds than in tanks (0.35 - 0.53 vs. 0.08 - 0.17). The results suggest raising Nile tilap.a with Azolladiets in p.nds to imp.ove growth and p.oduce fish with a better FA comp.sition, for the wellbeing of consumers.

关键词： Azolla Oreochromis niloticus Concrete Tank p.nd Growth Fatty Acid p.ytop.ankton

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Elimination of Carbon, Nitrogen and p.osp.orus in Domestic Wastewater through a Series of Anaerobic and Aerobic Reactors for a Develop.ng Country like Benin

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American Journal of Analytical Chemistry 2015年第7期6卷 577-584页

作者： Senandemi E. R. Mahunon Akuemaho V. O. Akowanou martin p. aina Benjamin K. Yao Dominique K. C. Sohounhloué Laboratoire des Sciences et Techniques de l’Eau (LSTE) Université d’Abomey-Calavi (UAC) Cotonou Benin Laboratoire de p.océdés Industriels de Synthèse de l’Environnement et des Energies Nouvelles Institut National Polytechnique Félix Houphou&euml t-Boigny de Yamoussoukro Yamoussoukro C&ocirc te d’Ivoire Laboratoire d’Etude et de Recherche en Chimie Ap.liquée (LERCA) Ecole Polytechnique d’Abomey-Calavi (EPAC) Université d’Abomey-Calavi (UAC) Cotonou Bénin

Waste water treatment in order to p.eserve water resources is one of the major concerns in develop.ng countries. This study aims to test the op.rating effectiveness of a p.lot designed on a basis of several laboratory exp.riments, which consists of an anaerobic and aerobic p.nd in series. The test was p.rformed through monitoring global p.rameters of p.llution. The results of the analysis of these p.rameters indicate an elimination of 91% of susp.nded solids, 68% of COD, 77% of BOD5, 61% of nitrate and 81% of p.osp.orus. It was also noticed that the anaerobic p.nd removes most, carbonaceous organic materials and esp.cially susp.nded matters;and the aerobic p.nd most, nitrogen and esp.cially p.osp.orus. This study reveals the effectiveness of the series connection of an anaerobic and aerobic p.nd for domestic wastewater treatment.

关键词： Wastewater Anaerobic/Aerobic p.nd p.lot

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Alternative Strategy for Develop.ent of Dielectric Calcium Cop.er Titanate‑Based Electrolytes for Low‑Temp.rature Solid Oxide Fuel Cells

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Nano-Micro Letters 2025年第1期17卷 310-332页

作者： Sajid Rauf Muhammad Bilal Hanif Zuhra Tayyab Matej Veis MAKYousaf Shah Naveed Mushtaq Dmitry Medvedev Yibin Tian Chen Xia martin Motola Bin Zhu College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060People’s Republic of China Dep.rtment of Inorganic Chemistry Faculty of Natural SciencesComenius University BratislavaIlkovicova684215 BratislavaSlovakia Energy Storage Joint Research Center School of Energy and EnvironmentSoutheast UniversityNanjing 210096People’s Republic of China Hydrogen Energy Laboratory Ural Federal University620002 EkaterinburgRussia Laboratory of Electrochemical Devices Based on Solid Oxide p.oton Electrolytes Institute of High Temperature Electrochemistry620066 EkaterinburgRussia School of Microelectronics Hubei UniversityWuhan 430062People’s Republic of China

The develop.ent of low-temp.rature solid oxide fuel cells(LT-SOFCs)is of significant imp.rtance for realizing the widesp.ead ap.lication of *** has stimulated a substantial materials research effort in develop.ng high oxide-ion conductivity in the electrolyte layer of *** this context,for the first time,a dielectric material,CaCu_(3)Ti_(4)O_(12)(CCTO)is designed for LT-SOFCs electrolyte ap.lication in this *** individual CCTO and its heterostructure materials with a p.typ. Ni_(0.8)Co_(0.15)Al_(0.05)LiO_(2−δ)(NCAL)semiconductor are evaluated as alternative electrolytes in LT-SOFC at 450–550℃.The single cell with the individual CCTO electrolyte exhibits a p.wer outp.t of ap.roximately 263 mW cm^(-2) and an op.n-circuit voltage(OCV)of 0.95 V at 550℃,while the cell with the CCTO–NCAL heterostructure electrolyte cap.bly delivers an imp.oved p.wer outp.t of ap.roximately 605 mW cm^(-2) along with a higher OCV over 1.0 V,which indicates the introduction of high hole-conducting NCAL into the CCTO could enhance the cell p.rformance rather than inducing any p.tential short-circuiting *** is found that these p.omising outcomes are due to the interp.ay of the dielectric material,its structure,and overall p.op.rties that led to imp.ove electrochemical mechanism in CCTO–***,density functional theory calculations p.ovide the detailed information about the electronic and structural p.op.rties of the CCTO and NCAL and their heterostructure CCTO–*** study thus p.ovides a new ap.roach for develop.ng new advanced electrolytes for LT-SOFCs.

关键词： LT-SOFCs Dielectric CaCu_(3)Ti_(4)O_(12) Semiconductor Ni_(0.8)Co_(0.15)Al_(0.05)LiO_(2−δ) Ionic conductivity Heterostructure electrolyte

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A New Triassic p.imitive Ichthyosaur from Yuanan, South China

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Acta Geologica Sinica(English Edition) 2013年第3期87卷 672-677页

作者： CHEN Xiaohong p. martin SANDER CHENG Long WANG Xiaofeng Wuhan Centre of China Geological Survey Steinmann-Institut für Geologie Mineralogie und Palontologie Universitt Bonn

Based on the systematic study of two fossil skeleton sp.cimens collected from the top.of the third member of the marine Lower Triassic Jialingjiang Formation of Yuanan, Hubei p.ovince, South China, a new Early Triassic p.imitive ichthyosaur Chaohusaurus zhang]iawanensis sp. nov. is rep.rted and described. The beds yielding the typ. material are correlated with the Neosp.thodus homeri-N, triangularis Conodont zone. The new taxon is most similar to Chaohusaurus geishanensis Young and Dong, 1972 in the shap. and configuration of the scap.la, forefin, p.lvic girdle and hindfin, p.esacral vertebral count and well-develop.d caudal p.ak, but distinguished from the latter by its larger size, the p.sition of the p.neal foramen in the centre of the p.rietal, the occurrence of a larger calcaneum in hindfin and the first sacral rib with distal exp.nsion. The new sp.cies exhibits common features of p.imitive ichthyosaurs such as：（1） the p.efrontal has an antero-dorsal shelf p.ojecting towards the orbit; （2） the up.er temp.ral fenestra is small; （3） the p.storbital and the squamosal meet laterally to the up.er temp.ral fenestra; and （4） cylindrical centra. However, more derived ichthyosaur characters are seen with the frontal sep.rated from the orbital dorsal margin by the contact of the p.efrontal and p.stfrontal, which offer new clues to the early radiation of ichthyosaurs.

关键词： vertebrate p.leontology rep.ilian ichthyosauria Lower Triassic (Sp.thian) Hubei p.ovince

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Oscillation of fourth-order delay dynamic equations

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Science China Mathematics 2015年第1期58卷 143-160页

作者： ZHANG Cheng Hui AGARWAL Ravi p. BOHNER martin LI Tong Xing School of Control Science and Engineering Shandong University Dep.rtment of Mathematics Texas A&M University-Kingsville 700 University Blvd.Kingsville TX 78363-8202 USA Dep.rtment of Mathematics and Statistics Missouri University of Science and TechnologyRolla MO 65409-0020 USA Dep.rtment of Mathematics Linyi University

This p.p.r is concerned with oscillatory behavior of a class of fourth-order delay dynamic equations on a time *** the general time scales case,four oscillation theorems are p.esented that can be used in cases where known results fail to *** results obtained can be ap.lied to an equation which is referred to as Swift-Hohenberg delay equation on a time *** criteria imp.ove a number of related contributions to the *** illustrative examp.es are p.ovided.

关键词： Swift-Hohenberg equation oscillation delay dynamic equation fourth-order time scale

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Farm-scale evaluation of the imp.ct of CrylAb Bt maize on canop. nontarget arthrop.ds： a 3-year study

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Insect Science 2018年第1期25卷 87-98页

作者： Maria Arias-martin Matias Garcia p.dro Castanera Felix Ortego Gema p. Farinos Centro de Investigaciones Biologicas CSIC Departamento de Biologia Medioambiental Grupo de Interaccion Planta-lnsecto Ramiro deMaeztu 9 28040 Madrid Spain

The cultivation of CrylAb-exp.essing genetically modified MON810 （Bt maize） has led to p.blic concern in Europ., regarding its imp.ct on nontarget arthro- p.ds （NTAs）. We have assessed the p.tential effects of DKC 6451 YG （MON810） maize on canop. NTAs in a farm-scale study p.rformed in Central Sp.in during 3 years. The study focused on hemip.eran herbivores （leafhop.ers and p.anthop.ers） and hymenop.eran p.rasitic wasp. （mymarids） collected by yellow sticky trap., which accounted for 72% of the total number of insects studied. The dynamics and abundance of these group. varied among years, but no significant differences were found between Bt and non-Bt maize, indicating that Bt maize had no negative effect on these taxa. Nonetheless, the CrylAb toxin was detected in 2 different arthrop.ds collected from Bt maize foliage, the cicadellids Zyginidia scutellaris and Emp.asca sp.. A retrosp.ctive p.wer analysis on the arthrop.d abundance data for our field trials has determined that Z. scutellaris and the family My- maridae have high cap.city to detect differences between the Bt maize and its isogenic counterp.rt. The use of these canop. NTAs as surrogates for assessing environmental imp.cts of Bt maize is discussed.

关键词： Cicadellidae MON810 Mymaridae risk assessment surrogate sp.cies Zyginidia scutellaris

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Sustainability of Intensively Exp.oited Aquifer Systems in the North China p.ain: Insights from Multip.e Environmental Tracers

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Journal of Earth Science 2014年第3期25卷 605-611页

作者： aina Su Zongyu Chen Jun Liu Wen Wei Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences

Environmental tracers are p.oving to be a unique tool for assessing groundwater sustainability, such as characterization of recharge, identification of p.thways and sources of contaminants, and p.ediction of groundwater change in resp.nse to excessive abstraction. This p.p.r help. to better understand the groundwater sustainability in the Quaternary aquifer from the tracer data in the North China p.ain. Relatively modern ground waters occur in the p.edmont p.ain with 3H-3He age less than 40 a within a dep.h 100 m. These ground waters are mainly recharged from the local p.ecip.tation and irrigation return. The recharge rate estimated by tracers is in the range of 0.24 to 0.32 m/a. p.leowater which is dated from 10 000 a B.p. to more than 35 000 a B.p. by radiocarbon dating is found in highly-confined p.rtions of Quaternary aquifer systems. This indicates that water recharge took p.ace during the p.st glacial p.riod. The tracers have suggested a slow natural rep.enishment rates to the central p.ain. The aquifer has been overexp.oited currently. Some strategies that can be imp.emented to p.omote a sustainable groundwater sup.ly are needed to imp.ement in future.

关键词： sustainability groundwater exp.oited environmental tracer North China p.ain.

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Steady-State Radial Flow Modeling through the p.oduction Well in the Confined Aquifer of Monzoungoudo,Benin

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Op.n Journal of Fluid Dynamics 2019年第2期9卷 107-118页

作者： Francois de p.ule Codo Babilas Hountondji martin p.aina Laboratory for Water Sciences and Technology Department of Water and SanitationNational Water InstituteUniversity of Abomey-CalaviCotonouBenin p.ysical Mathematics and Ap.lications University of Abomey-CalaviCotonouBenin

This study aims to develop.a mathematical analysis for one-dimensional modeling of a radial flow through a p.oduction well drilled in a confined aquifer, in the case of steady-state flow conditions. An analytical solution has derived from that exp.ession for estimation of drawdowns according to different flowrates. Through that p.ocess, the evaluation of static p.essure, the calculation of hydraulic charge due to the waterflow through the well is evaluated, the drawdowns curves are drawn and at last, the obtained curves are analyzed. The curves obtained for the different flow rates have an asymp.otic direction, the axis of the hydraulic charges. The variation of the hydraulic charge dep.nds on the radial distance for different flow rates. The p.p.int, is a common p.int of all curves obtained for different p.oduction flowrates in the well. This p.int is where the well p.oduction flowrate is op.imum for the op.imal hydraulic charge.

关键词： Confined Aquifer p.oduction Well Radial Flow Steady-State Flow Drawdown Cone of Dep.ession

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Influence of p. on Water Hyacinth p.nds Treating and Recycling Wastewater

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Journal of Water Resource and p.otection 2022年第2期14卷 86-99页

作者： Sèna p.ace Hounkp. martin Crap.er Albant Sagbo Edmond Adjovi martin p.p.n aina Ecole Nationale Sup.rieure des Travaux p.blics Université des Sciences Technologies Ingénierie et Mathématiques d’Abomey Abomey Benin Institute of Infrastructure and Environment School of Engineering University of Edinburgh Edinburgh UK Institut National de l’Eau Université d’Abomey-Calavi Abomey-Calavi Benin

This work has examined the effects of p. on the treatment efficiency and biomass p.oduction rate of water hyacinth p.nds (WHp. treating domestic wastewater. Exp.riments were carried out outdoor in WHp. working under batch and subtrop.cal environmental conditions, using p.e-treated sewage with p. varying from 5 to 9. It was observed that the p.ants regulated the p. of the medium to within 6.4 to 7.1 during the treatment p.ocesses indep.ndently of influent wastewater p. ranges. This adjustment reduced the treatment p.rformances and the biomass p.oduction in p.nds, the alkaline conditions in p.nds being less favorable to the activities of the p.ants. The op.imal removal and biomass p.oduction was achieved with influent p. of 7 lying in the above interval. So the op.imum influent p. for the growth of p.ants and the removal of nutrients and organic matters in WHp.is within p. 6.4 to p. 7.1.

关键词： Sewage Treatment Biomass p.oduction Water Hyacinth p.

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