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Selective catalytic reduction of NO by NH3 on cerium modified faujasite zeolite prepared from aluminum scraps and industrial metasilicate

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Journal of Rare Earths 2020年第3期38卷 250-256页

作者： Rahma Abid gerard delahay Hassib Tounsi Laboratory of Advanced Materials National School of Engineers of SfaxUniversity of SfaxTunisia Institut Charles gerhardt ENSCM"Advanced Materials for Health and Catalysis"240 Av Professor Emile Jeanbrau34296 MontpellierFrance

This work was devoted to the study of the selective catalytic reduction of NO by NH3 on calcined and hydrothermal treated cerium loaded zeolite *** parent faujasite zeolite Na-F(Si/Al=1.32 and SBET=749 m^2/g) used as support for the preparation of the catalysts was obtained from industrial sodium metasilicate and aluminum *** expected,the NO conversion increases with increasing the percentage of cerium in the structure of the faujasite *** NO conversion into N2 is reached at 400℃at a space velocity of 250 000 h^-*** high conversion is due to the redox shift between Ce^3+/Ce^4+and the strong acid sites related to the rare earth present in the framework that is the key in SCR of NO ***,the highest loaded cerium catalyst retains almost its activity after hydrothermal treatment at 850℃.This higher loading is desirable for both activity and stability provided that two stages of preparation are used to put the Ce ions in the sodalite cages.

关键词： Aluminum scraps Ce-Y NH3-SCR Hydrothermal stability

Ultrasound-assistant preparation of Cu-SAPO-34 nanocatalyst for selective catalytic reduction of NO by NH_3

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Journal of Environmental Sciences 2015年第9期27卷 135-143页

作者： Parvaneh Nakhostin Panahi Ali Niaei Darush Salari Seyed Mahdi Mousavi gérard delahay Department of Chemistry Faculty of Science University of Zanjan Department of Chemical Engineering & Petroleum University of Tabriz Department of Applied Chemistry Faculty of Chemistry University of Tabriz Faculty of Chemistry University of Kashan Institut Charles gerhardt UMR 5253 CNRS/UM2/ENSCM/UM1 Equipe"Matériaux Avancés pour la Catalyse et la Santé"Ecole Nationale Supérieure de Chimie de Montpellier 8 rue de l'Ecole Normale34296 Montpellier cedex France

The influence of the various preparation methods of Cu-SAPO-34 nanocatalysts on the selective catalytic reduction of NO with NH3 under excess oxygen was studied. Cu-SAPO-34 nanocatalysts were prepared by using four techniques： conventional impregnation（IM）,ultrasound-enhanced impregnation（UIM）, conventional deposition precipitation（DP） using Na OH and homogeneous deposition precipitation（HDP） using urea. These catalysts were characterized in detail by various techniques such as N2-sorption, XRD, TEM, H2-TPR,NH3-TPD and XPS to understand the catalyst structure, the nature and the dispersed state of the copper species, and the acid sites for NH3 adsorption. All of the nanocatalysts showed high activities for NO removal. However, the activities were different and followed the sequence of Cu-SAPO-34（UIM）〉 Cu-SAPO-34（HDP）〉 Cu-SAPO-34（IM）〉 Cu-SAPO-34（DP）.Based on the obtained results, it was concluded that the NO conversion on Cu-SAPO-34 nanocatalysts was mainly related to the high reducibility of the isolated Cu^2＋ions and Cu O species, the number of the acid sites and the dispersion of Cu O species on SAPO-34.

关键词： NO NH3-SCR Cu-SAPO-34 Ultrasonic impregnation

Late-onset Very long-chain acyl-CoA dehydrogenase deficiency diagnosis complicated by fulminant myocarditis in adult patient

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Journal of Intensive Medicine 2024年第3期4卷 400-402页

作者： Martin gérard Clair Douillard Julien Poissy Mehdi Marzouk Christophe Vinsonneau Intensive Care Unit Centre Hospitalier de Bethune-BeuvryBethuneFrance Endocrinology diabetologymetabolism departmentLille reference centre of inborn errors of metabolismLille University HospitalLilleFrance Inserm U1285 CHU LillePôle de réanimationCNRSUMR 8576-UGSF-Unitéde Glycobiologie Structurale et FonctionnelleUniv.LilleLilleFrance

Introduction A 21-year-old woman presented to the emergency department with fatigue,abdominal pain and *** physical activity in school was strictly *** had no family medical history and no personal history but reported frequent episodes of nausea and vomiting lasting 2 to 7 days during the past two years,as well as a weight loss of 9 kg due to reactive anorexia(Body Mass Index 17.5),without triggering factors or *** gastrointestinal symptoms led to the detection of isolated elevated transaminases(aspartate aminotransferase[AST]190 U/L and alanine aminotransferase[ALT]170 U/L);however,the patient did not pursue the proposed etiological *** has been using cannabis once a day for several years,with an increase in consumption over the past year,but no *** reported no other recent change in her habits.

关键词： diagnosis patient elevated

Community Perception of Riparian Corridors Ecosystem Services and Implications for Environmental Education in Upper Oueme Catchment in Benin, West Africa

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Open Journal of Ecology 2024年第2期14卷 125-147页

作者： Socrate Mercator Dossou Kinnoumè Serge Adomou gérard Nounagnon gouwakinnou Thierry Dèhouégnon Houéhanou Laboratory of Ecology Botany and Plant Biology Faculty of Agronomy University of Parakou Parakou Republic of Benin

The assessment of the local community perception of the value of riparian corridors is relevant to understand their attitude towards the conservation of such ecosystem. We conducted a semi-structured survey on the perception and importance attributed to the ecosystem services (ESs) provided by riparian corridors in 368 households across 70 villages located in a buffer zone of 5 km of servitude around the permanent rivers of the Upper Oueme watershed in Benin. We found that local communities easily reported provisioning and cultural ESs than regulating and supporting ones, indicating their misunderstanding of the main role of riparian corridor. Moreover, the supply of cropping areas was perceived as the most important ES. Educated respondents and high-income households had more knowledge of regulating ESs and supporting ESs, respectively. Overall, the highly perceived importance of the provision of cropping areas indicates a potential risk of agricultural encroachment of riparian corridors. We suggest the consideration of the current local perception of riparian corridor’s role in designing a sound environmental education aiming at the change of local population’s perception. This perception shift will promote a sustainable management of the riparian corridors.

关键词： Local Knowledge Direct Use Value Soil Formation Migration Importance Value Benin

Assessment of the Recent Hydromorphological Features of Nokoue Lake and Its Channels (South-East Benin)

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Open Journal of Modern Hydrology 2024年第1期14卷 33-55页

作者： Tètchodiwèï Julie-Billard Yonouwinhi gérard Alfred Franck Assiom d’Almeida Felix Kofi Abagale Akuemaho Virgile Onésime Akowanou Laboratory of Applied Hydrology (LHA) National Institute of water (INE) African Centre of Excellence for Water and Sanitation (C2EA) University of Abomey-Calavi (UAC) Cotonou Benin International Chair in Mathematical Physics and Applications (ICMPA–UNESCO Chair) University of Abomey-Calavi (UAC) Cotonou Benin Laboratory of geology Mining and Environment (LGME) Faculty of Science and Technology (FAST) University of Abomey-Calavi (UAC) Cotonou Benin West African Centre for Water Irrigation and Sustainable Agriculture (WACWISA) University of Development Studies (UDS) Tamale Ghana Laboratory of Sciences and Technology for Water and Environment (LSTEE) University of Abomey-Calavi (UAC) Cotonou Benin

Based on 2022 and 2023 hydrometric data and satellite images (Sentinel 2022, SPOT 2010), this study aims to present the Nokoué Lake and its channels’ re-cent hydromorphological characteristics. Integrating flow, tributary morphology, and topography data determined specific power values along the axes studied. The values obtained range from 2.69 to 12.92 W/m2 for Ouémé River and 2.46 to 10.99 W/m2 for Sô River. The resulting water erosion on banks and bottoms is of linear, areolar, or gully and claw types. Lake bathymetry varies from -0.5 to -2.6 m (low flow period) and -1 to -4 m;in the Ouémé, Sô, and Totchè rivers, it varies from -5 m to -7 m, reaching -10 m at the Cotonou channel entrance (flood period). Bathymetric profiles reveal varied “U”, “V” and “Intermediate” bottom morphologies, influenced by erosion/sedimentation processes and human activities. The flow facies identified are lentic in the northern tributaries and lotic in the Cotonou and Totchè canals. Spatial analysis identified nine (09) thematic classes. In 2022, the surface area of the water body has increased from 274 km2 at low water to 280 km2 at high water, whereas in 2010 (a recent year of exceptional flooding), the surface area was 270 km2 at low water and 277 km2 at high water. Significant changes in land use are observed between 2010 and 2022. The floodplain area decreased slightly, from 421 km2 in 2010 (year of exceptional flooding) to 419 km2 in 2022. The evolution of land use shows a progressive expansion of the urban environment to the detriment of the natural environment. In the medium to long term, this trend could threaten the hydromorphological balance and even the existence of this important lagoon ecosystem.

关键词： Nokoué Lake Ouémé River Sô River Cotonou Channel Hydromorphology

Benign Nasosinus Tumors: Epidemiological, Clinical, Morphological, Therapeutic, and Evolutionary Aspects at the Adolphe SICE general Hospital in Pointe-Noire (Congo-Brazzaville)

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Open Journal of Pathology 2024年第1期14卷 1-10页

作者： Sylvain Diembi Sydney Frousse Christian Ngatali Harol Boris Otouana gérard Chidrel gouoni Franck Itiere Odzili Donatien Moukassa gontran Ondzotto ENT Department Adolphe SICE General Hospital Pointe-Noire Congo Oncology Department Loandjili General Hospital Pointe-Noire Congo ENT Department Brazzaville Hospital and University Center Brazzaville Congo Master’s Department Health & Human Biology FSSA UMNG Brazzaville Congo

Introduction: Benign nasosinus tumors (BNST) of epithelial origin are relatively rare and arise from the various lining tissues of the nasal and sinus cavities, and from glands developed from these epithelial invaginations. These include nasosinusal polyps, pleiomorphic adenoma and inverted papilloma. The aim of our study was to investigate the epidemiological, clinical, morphological, therapeutic, and evolutionary particularities of these three clinical entities, including two tumors with the potential for progressive malignancy (pleiomorphic adenoma and inverted papilloma) and one strictly benign tumor with a favorable evolution (nasosinus polyp or Schneider polyp). Materials and Methods: This was a retrospective, analytical, cross-sectional study conducted from January 1, 2006 to December 31, 2019 (13 years), in the Department of Otolaryngology and Cervicofacial Surgery at Adolphe SICE Hospital, Pointe-Noire, Congo-Brazzaville. Results: During the study period, 74 patients were registered for a nasosinus tumor, of which 23 were benign tumors of epithelial origin (31%) distributed as follows: 15 cases of nasosinus polyp, 5 cases of pleomorphic adenoma and 3 cases of inverted papilloma. The mean age was 42.5 for polyps, with an estimated median of 38, and 42.9 for the other two entities (pleomorphic adenoma and inverted papilloma), with an estimated median of 41. Nasosinus allergy accounted for 17% of cases, followed by chronic sinusitis (12%);however, in 49% of cases, the patient’s history was not specified. There was no sexual predominance, the sex ratio being 1.08. Occupation, socio-economic level, and education had no impact on the development of these tumors. Most of our patients (52%, 12 cases) had a consultation delay of more than one (1) year, whatever the histological nature of the tumor. The complete nasosinus syndrome (NSS) included nasal obstruction, rhinorrhea, epistaxis, and anosmia, and was found in 19 cases (83%), most often reflecting a nasosinus p

关键词： Nasosinus Polyp Pleomorphic Adenoma Inverted Papilloma Epidemiology Clinical Features Therapeutic Management

Socioenvironmental Drivers of Farmers’ Perceptions of Climate Change Risk in Agroforestry Parklands of West Atacora in Benin (West Africa)

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Open Journal of Ecology 2024年第1期14卷 54-65页

作者： Amos Baninwain Nambima Thierry Dèhouégnon Houehanou Narcisse Yehouenou Dowo Michée Adjacou Abdul Sodick Alassiri gérard gouwakinnou Laboratory of Ecology Botany and Plant Biology (LEB) Faculty of Agronomy (FA) University of Parakou (UP) Parakou Republic of Benin

Throughout the world, climate change is threatening the human population. In West Africa, smallholder farmers in indigenous agricultural societies typically hold considerable knowledge. Therefore, this study was conducted in West Atacora of Benin Republic to assess the drivers of farmers’ perceptions of climate change risk. We used a random sampling technique to select 360 households’ heads who were interviewed regarding different climate change risks perception. Binomial logistic regression was used to assess the drivers of farmers’ perceptions of climate change risks. The results showed that the farmers in drier areas had a higher perception of the global risk of climate change than those in humid areas. The same trend was observed for the seven different individual’s climate change risk investigated. The study identified also membership of farm organizations as main sociodemographic characteristic that explains farmers’ perception of climate change risk perception. These findings are helpful tools to sensitize the local people on climate change risk and cope with the risk in agricultural lands.

关键词： Climate Change Risk Local Ecological Knowledge Socio-Demographic Characteristics Benin West Africa

Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

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Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： gürel Cam Ali günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200 Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(WA-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(WAAM) 3-D printing High deposition rate

Recent research in mechanical properties of geopolymer-based ultrahigh-performance concrete:A review

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Defence Technology（防务技术） 2024年第2期32卷 67-88页

作者： g.Murali Division of Research&Innovation Uttaranchal UniversityDehradun 248007India

Due to the growing need for sustainable and ultra-high-strength construction materials,scientists have created an innovative ultra-high-performance concrete called geopolymer based ultra-highperformance concrete(gUHPC).Besides,in the last few decades,there have been a lot of explosions and ballistic attacks around the world,which have killed many civilians and fighters in border *** this context,this article reviews the fresh state and mechanical properties of ***,the ingredients of gUHPC and fresh properties such as setting time and flowability are briefly ***,the review of compressive strength,flexure strength,tensile strength and modulus of elasticity of fibrous ***,the blast and projectile impact resistance performance was ***,the microstructural characteristics were reviewed using the scanning electron microscope and X-ray Powder *** review outcome reveals that the mechanical properties were increased when 30%silica fume was added to a higher dose of steel fibre to improve the microstructure of *** is hypothesized that the brittleness of gUHPC was mitigated by adding 1.5%steel fibre reinforcement,which played a role in the decrease of contact explosion cratering and *** the need for cement in gUHPC was a key factor in the review,indicating a promising potential for lowering carbon ***,gUHPC research is still in its early stages,so more study is required before its full potential can be utilized.

关键词： Mechanical properties Blast Projectile impact Fibre geopolymer Silica fume Alkaline activators