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中国有色金属学会会刊：英文版 2010年第S3期20卷 734-738页

作者： S.TERZI L.SALVO M.SUERY A.DAHLE E.BOLLER Australian Research Council centre of Excellence for design in Light Metals Materials EngineeringThe University of QueenslandBrisbane Queensland 4072Australia Université de Grenoble Science et Ingénierie des Matériaux et ProcédésGénie Physique et Mécanique des MatériauxUMR CNRS 5266Grenoble INPUniversité Joseph FourrierBP4638402 Saint-Martin d'Hères CedexFrance European Synchrotron Radiation Facility 6 rue Jules HorowitzBP22038043 Grenoble CedexFrance

The aim of this paper is to report the results of experiments carried out on Al-Cu alloys with different Cu contents,studying the microstructure evolution during holding in the semi-solid *** 3-D microstructure was observed by in situ X-ray microtomography carried out at ESRF Grenoble,*** variation of the solid-liquid interface area per unit volume during holding was *** addition,local observations show that two coarsening mechanisms of the solid particles occur simultaneously:dissolution of small particles to the benefit of larger ones by an Ostwald-type mechanism and the growth of necks between solid particles due to *** observations confirm that in situ X-ray tomography is a very powerful tool to study the microstructure evolution in the semi-solid state and the influencing mechanisms in real-time.

关键词： Al-Cu alloys microtomography remelting microstructure

Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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Journal of Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： S.Pérez-Rodríguez M.Gutiérrez-Roa C.Giménez-Rubio D.Ríos-Ruiz P.Arévalo-Cid M.V.Martínez-Huerta A.Zitolo M.J.Lázaro D.Sebastián Instituto de Carboquímica(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y Petroleoquímica(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 M KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide

The Sword of Damocles behind the Curtain of the Earth’s Global Warming: A Review

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International Journal of Geosciences 2024年第2期15卷 119-136页

作者： Jacques Bourgois Institut des Sciences de la Terre Paris (iSTeP) Unité Mixte de Recherche (UMR) 7193 Université Pierre et Marie Curie (UPMC)/Université Paris 06 Paris France iSTeP UMR 7193 Centre National de la Recherche Scientifique (CNRS) Paris France

The “mainstream” climatology (MSC)—i.e. which includes the Intergovernmental Panel on Climate Change (IPCC) community—considers the present day massive release of greenhouse gases into the atmosphere as the main cause of the current global warming trend. The main inference from this stance is that the increase in temperature must occur after the release of greenhouse gases originating from the anthropic activities. However, no scientific evidence has been provided for this basic notion. Earth paleoclimatic records document the antecedence of temperature over CO2 levels. For the past 65 Ma, the temperature parameter has controlled the subsequent increase in CO2. This includes the three rapid aberrant shifts and extreme climate transients at 55 Ma, 34 Ma, and 23 Ma REF _Ref159913672 \r \h \* MERGEFORmat [1]. The simple fact of their existence points to the potential for highly nonlinear responses in climate forcing. Whatever these shifts and transients are, CO2 remains a second order parameter in their evolution through time. Confronted with the past, a suitable response must therefore be given to the unresolved question of whether the CO2 trends precede the temperature trends in the current period, or not. The assertion that the current global warming is anthropogenic in origin implicitly presupposes a change of paradigm, with the consequence (the increase in CO2 levels) that occurred in Earth’s past being positioned as the cause of the warming for its present day climatic evolution. The compulsory assumption regarding the antecedence of CO2 levels over the temperature trends is associated with the haziness of the methodological framework—i.e. the paradigm—and tightens the research fields on the likely origins of global warming. The possible involvement of an “aberrant” natural event, hidden behind the massive release of greenhouse gases, has not been considered by the MSC.

关键词： Climate CO2 Temperature Paleoclimate Warming

Study of the Optimal Conditions for Anaerobic Digestion of Cow Dung in Households in Cote d’Ivoire

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Open Journal of Applied Sciences 2024年第9期14卷 2679-2696页

作者： Sahi Louh Theophile Roch Ori Kamenan Blaise Koua Prosper Gbaha Laboratoire de Technologie Unit de Formation et Recherche Sciences des Structures de la Matire et de Technologie (UFR SSMT) Universit Flix Houphout Boigny Abidjan Cte dIvoire Laboratoire des Sciences de la matire de lEnvironnement et de lEnergie Solaire Unit de Formation et Recherche Sciences des Structures de la Matire et de Technologie (UFR SSMT) Universit Flix Houphout Boigny Abidjan Cte dIvoire Laboratoire des Procds Industriels de Synthse de lEnvironnement et des Energies Nouvelles Institut National Polytechnique Flix Houphout Boigny Yamoussoukro Cte dIvoire

This paper investigates the optimal conditions for methanisation applied to cow dung. Four experimental 25 liters digesters were used in this work. The best biogas yield is obtained when the digester is installed in a metal box and exposed to sunlight. The temperature in this digester varied between 25˚C and 37˚C. The dry matter content of the collected cow dung was 15.5%. The digester was fed with 9 kg of cow dung mixed with 8.5 litres of water, one litre of cassava effluent and 200 ml of human urine. After a retention period of 22 days, the biogas obtained was 67% methane and 21% carbon dioxide. The use of human urine and cassava effluent improved the quality of the biogas.

关键词： Methanisation Cassava Effluent Human Urine Cow Dung Biogas

Decomposition behavior of yttria-stabilized zirconia and its effect on directed energy deposited Ti-based composite material

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Journal of materials Science & Technology 2022年第17期112卷 138-150页

作者： Gwanghyo Choi Won Seok Choi Yoon Sun Lee Dahye Kim Ji Hyun Sung Seungjun An Chang-Seok Oh Amine Hattal Madjid Djemai Brigitte Bacroix Guy Dirras Pyuck-Pa Choi Department of materials Science and Engineering Korea Advanced Institute of Science and TechnologyDaejeon 34141Republic of Korea 3D Additive Manufacturing Application Tech.Center Korea Institute of Industrial TechnologyDaegu 42994Republic of Korea InssTek Co. Daejeon 04763Republic of Korea Korea Institute of materials Science 797 ChangwondaeroChangwon 51508Republic of Korea UniversitéSorbonne Paris Nord Laboratoire des Sciences des Procédés et des MatériauxLSPMCNRSUPR 3407F-93430VilletaneuseFrance Z3Dlab Parc Technologique26 Rue des SablonsMontmagny 95360France CNRS UPR3407Laboratoire des Sciences des Procédés et des MatériauxLSPMUniversitéSorbonne Paris NordF-93430VilletaneuseFrance

We report on the microstructure and the strengthening mechanisms of additively manufactured parts fabricated by directed energy deposition of Ti-6Al-4V(Ti64)powders blended with yttria-stabilized zirconia(YSZ)*** specimens showed refined microstructures as compared to bare as-deposited Ti64,where theαand columnar priorβgrain sizes decreased with increasing YSZ *** YSZ nanoparticles decomposed during the deposition process and led to the formation of yttrium oxide and some excess oxygen in the Ti64 *** decrease in the sizes of the priorβgrains could be attributed to the increasing amount of dissolved oxygen and yttrium,which promoted constitutional ***,the reduction in the size of theαgrains could be ascribed to a shift of the onset of theβ→α+βtransformation to a higher temperature and shorter time with increasing concentration of dissolved ***,the contributions of the underlying strengthening mechanisms for the as-deposited specimens were quantitatively determined.

关键词： Additive manufacturing Directed energy deposition Metal matrix composites Titanium alloys Yttrium-stabilized zirconia

Physico-Chemical Characterization of Some Honeys from the Savannah-Gallery Forest Complex and Primary Forest in Gabon

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Open Journal of Applied Sciences 2024年第7期14卷 1904-1917页

作者： Charline Obone Madi Guirema Abaker Silas Davy Mbadinga Boubala Estelle Dumont Gino Boussiengui-Boussiengui Alexis Nicaise Lepengue Dpartement Sciences Fondamental de lIngnieur Institut National Suprieur dAgronomie et de Biotechnologies Universit des Sciences et Techniques de Masuku Franceville Gabon Dpartement de Biochimie Facult des Sciences Universit des Sciences et Techniques de Masuku Franceville Gabon LAboratoire de Recherche Multidisciplinaire en Environnement (LARME) USTM Franceville Gabon Dpartement de Phytotechnologie Institut National Suprieur dAgronomie et de Biotechnologies Universit des Sciences et Techniques de Masuku Franceville Gabon

Honey harvesting throughout beekeeping is a technology recently introduced in Gabon comparing to the other African countries well known in international honey trade. The purpose of this study is to contribute to the knowledge of the quality of multi-flower honeys from the savannah-gallery forest complex and primary forest not well documented in Gabon. Physical and chemical parameters of different honeys were analyzed using the official methods of analysis of the Association of Official Analytical Chemists. The results of physico-chemical analysis show variations in pH (3.4 to 3.9), free acidity (37.12 to 76.65 meq∙kg−1), water content (17.49% to 21.21%), electrical conductivity (0.64 to 1.24 mS∙cm−1), density (1.02 to 1.03) and total sugar content (77% to 82%). These variations were significantly different (p < 0.05) between certain honeys, but independent of the type of ecosystem considered. The pH values confirmed the botanical origin of the five honeys. The physico-chemical parameters of the honeys show significant correlations (p < 0.05). Moisture content is negatively correlated with conductivity (r = −0.628), pH (r = −0.631), density (r = −0.552) and total sugar content (r = −0.890). Conductivity is positively correlated with free acidity (r = 0.688) and total sugar content (r = 0.776), and negatively correlated with water content (r = −0.628). All honeys were in line with Codex Alimentarius standards, except for 3 types of honey (M1, M2 and M4) for free acidity and electrical conductivity, showing possible fermentation of these honeys.

关键词： Physico-Chemical Parameters Honey Gabon Codex Alimentarius

Prediction model for the diffusion length in silicon-based solar cells

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Journal of Semiconductors 2009年第7期30卷 3-6页

作者： Cheknane A Benouaz T Laboratoire d'Etude et Dveloppement des matriaux Semiconducteurs et Dilectrques Universit Amar Telidji de Laghouat Laboratoire de Modlisation UniversitAbou BakarBelkaid de Tlemcen Algrie

A novel approach to compute diffusion lengths in solar cells is presented. Thus, a simulation is done; it aims to give computational support to the general development of a neural networks （NNs）, which is a very powerful predictive modelling technique used to predict the diffusion length in mono-crystalline silicon solar cells. Furthermore, the computation of the diffusion length and the comparison with measurement data, using the infrared injection method, are presented and discussed.

关键词： diffusion length minority-cartier lifetime infrared injection solar cell prediction modelling

Thermoluminescent response of gamma irradiated Na^(+)–Cu^(+) ionexchanged silicate glass in large dose range

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Nuclear Science and Techniques 2023年第5期34卷 22-32页

作者： Safa Toumi Khaled Farah Laboratoire de Physico‑Chimie des matériaux Département de PhysiqueFacultédes Sciences de MonastirUniversitéde MonastirMonastirTunisia Institut Supérieur du Transport et de la Logistique de Sousse Universitéde Sousse4023 SousseTunisia Laboratoire de Recherche en Energie et matière Développement des Sciences Nucléaires(LR16CNSTN02)Centre National des Sciences et Technologies Nucléaires2020 Sidi‑ThabetTunisia

The introduction of metals into vitreous matrices is the origin of various interesting phenomena;in particular,the presence of copper ions in glass has been the subject of considerable research because of its numerous *** ion-exchange process is primarily used to introduce copper ions into glass *** thermoluminescence(TL)of silicate glass was studied to evaluate its potential as gamma-sensitive material for dosimetric applications;the effect of copper doping on the thermoluminescent sensitivity was investigated using the Cu-Na ion-exchange technique for different concentrations and doping conditions,over a wide dose range of 10 mGy to 100 *** results showed that Cu doping significantly improved the sensitivity of the glasses to gamma *** the ion-exchange,two peaks appeared in the glow curves at approximately 175 and 230°C,respectively,which possibly originated from the Cu^(+) centers,along with a weak TL peak at around 320℃.We also attempted to explain the origin of the observed thermoluminescence by exploiting the Electron paramagnetic resonance(EPR)*** results clearly show quenching of the TL emission with increasing copper *** present work indicates that the thermoluminescence response of these glasses to gamma rays can be reasonably measured in the range of 0.001-100 *** study also facilitates the understanding of the basic TL mechanism in this glass system.

关键词： Cu-Na ion-exchange Silicate glass Thermoluminescence Gamma irradiation Electron paramagnetic resonance

Serrated plastic flow behavior and microstructure in a Zr-based bulk metallic glass processed by surface mechanical attrition treatment

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Journal of Iron and Steel Research International 2017年第4期24卷 475-482页

作者： Juan-juan Liu Qing Wang Kang Sun Sebastien Gravier Jean-jacque Blandin Bao-an Sun Jian Lu Laboratory for Microstructures Institute of MaterialsShanghai UniversityShanghai 200072China Department of Mechanical and Biomedical Engineering City University of Hong Kong Science et Ingenierie des matériaux et des Procédés(SIMAP) University of Grenoble/CNRSGrenoble-INPSaint-Martin d'Heres Cedex 38402France

The serrated plastic flow,microstructure and residual stress of a Zr_（55）Cu_（30）Ni_5Al_（10） bulk metallic glass（BMG）undergone surface mechanical attrition treatment（Smat）have been investigated by a combination of compression tests with scanning electron microscopy（SEM）,high resolution transmission electron microscopy（HRTEM）and the incremental hole-drilling strain-gage *** is found that Smat leads to various microstructural modifications and residual stress distribution in the surface layers of the Zrbased BMG due to the mechanically-induced nanocrystallization and generation of shear *** a result,the BMG alloy exhibits a remarkable work-hardening like behavior and significant increase of plastic strain from less than 1%to 15%,and its plastic deformation dynamics yields a power-law distribution of shear *** upon the analysis of the experimental results,it is indicated that this can be connected to the Smat-induced microstructural modifications and the resulting residual compressive stress in the Zr-based BMG.

关键词： Bulk metallic glass Surface mechanical attrition treatment Serrated flow Microstructure Residual stress

Trends of Land Use and Land Cover Change in the Savannah Ecological of the Protected Area Reserve Partielle de Dosso, Niger

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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