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Elaboration of AlSi10Mg casting alloys using directional solidification processing

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 509-515页

作者： Khadoudja Ghedjati Eric fleury Mohamed Seghir hamani Mostefa Benchiheub Khaider Bouacha bernard Bolle Systems and Advanced Materials Laboratory (LASMA) Department of Physics Faculty of Science Badji Mokhtar University of Annaba Microstructure Investigation and Material Mechanic Laboratory (LEM3) CNRS Lorraine-Metz University Faculty of Science Souk Ahras University Foundry Research Laboratory (LRF) Department of Physics Faculty of Science Badji Mokhtar University of Annaba

The effects of pulling velocity on the solidification behavior and microstructural parameters of A1Sil0Mg alloys prepared in a Bridgman-type directional solidification furnace were investigated. The microstructure, particularly the secondary dendritic arm spacing （SDAS）, and the Brinell hardness （Bh） of the solidified A1Sil0Mg alloys were characterized for samples with cylindrical shapes and differ- ent conicities （θ = 0°, 5°, and 10°）. Microstructural studies revealed an increased density of ct-A1 phase dendrites and a decreased interden- dritic distance with increasing pulling velocity. The dendrites were found to be preferentially oriented along the pulling direction for low pulling velocities. For larger pulling velocities, the dendrites grew first in the cooling direction but then broke as others nucleated and coars- ened. The hB values of the solidified samples increased as the pulling velocity increased. In regard to sample conicity, smaller dendrites were observed for an apex angle of θ = 5°, resulting in the largest hB value. This result was interpreted in terms of the favorable orientation of the dendrite along the pulling direction.

关键词： aluminum-silicon-magnesium alloys directional solidification Bridgman technique mierostructure hardness heat flow growth

Carboxymethyl glycoside lactone(CMGL) synthons:Scope of the method and preliminary results on step growth polymerization of α-azide-ω-alkyne glycomonomers

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Science China Chemistry 2010年第9期53卷 1880-1887页

作者： ChAMBERT Stéphane bernard Julien fleury Etienne QUENEAU Yves INSA-Lyon Laboratoire de Chimie Organique et Bioorganique Bat.J.Verne 20 Avenue A.Einstein69621 Villeurbanne CedexFrance ICBMS Institut de Chimie et de Biochimie Moléculaires et SupramoléculairesUMR5246 CNRS université de Lyon université Lyon 1 INSA-Lyon CPE-Lyon Bat.Curien 43 Bd du 11 Novembre 1918F 69622 VilleurbanneFrance INSA-LYON IMP1ngénierie des Matériaux Polymères UMR5223 université de Lyon université Claude Bernard Lyon 1F-69621 Villeurbanne CedexFrance

Carboxymethyl glycoside lactones(CMGLs) are bicyclic synthons which open readily for accessing new types of pseudo-glycoconjugates,such as sugar-amino acid hybrids,neoglycolipids,pseudodisaccharides,and membrane imaging *** lactone opening,free Oh-2 is available for further functionalization,leading to 1,2-bisfunctionalized *** strategy is illustrated herein with new polymerizable systems of the AB type bearing both azide and alkyne functions prepared from α or β gluco-CMGL *** the reaction of lactones with propargylamine,an azido group was introduced by two different sequences leading to either the 2-manno-azido or the 6-gluco-azido *** capability of these AB monomers to undergo step growth polymerization through copper(I) catalyzed alkyne-azide cycloaddition(CuAAC) and generate glycopolytriazoles was evidenced.

关键词： carbohydrates glycopolymers lactones click chemistry step growth polymerization glycoconjugates azides alkynes huisgen cycloaddition

Identifying Suitable Sites for CSP Plants Using AhP,Fuzzy AhP,and Full Consistency Method:A Case Study of ChAD

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Energy Engineering 2025年第3期122卷 943-969页

作者： bernard Bayangbe Ababacar Thiam El hadji I.Cissé Kory Faye Efficiency and Energetic Systems Research Group Physics DepartmentAlioune Diop UniversityBambeyBP 30Senegal Water EnergyEnvironment and Industrial Processes LaboratoryPolytechnic SchoolCheikh Anta Diop UniversityDakarBP 5085Senegal

Concentrating Solar Power(CSP)is one of the most promising solar technologies for sustainable power generation in countrieswith high solar potential,*** suitable sites is of great importance for deploying solar power *** work focuses on the identification of potential sites for the installation of solar power plants in Chad as well as a comparative analysis using the Analytical hierarchy Process(AhP),Fuzzy Analytical hierarchy Process(FAhP),and Full Consistency Method(FUCOM).The results show that 35%of the Chadian territory,i.e.,an area of 449,400 km2,is compatible with the implementation of Concentrating Solar *** North,North,East,Southeast,and East zones are the most *** main criteria for influence are direct normal irradiation,the soil slope,and the water *** gave a weight of 41.9%for Direct Normal Irradiation(DNI)compared to 32.71%and 31.81%for AhP and *** method can be applied to other renewable energy technologies such as photovoltaics,wind power,and *** its different analyses will be a valuable tool for planning any renewable energy project in *** work should also facilitate the techno-economic analysis of future CSP plants in Chad.

关键词： Concentrating solar power analytical hierarchy process fuzzy analytical hierarchy process full consistency method geographic information system direct normal irradiation

Exploring Malnutrition Risk among Infants under Five Years in Guéra Province, Chad: A Cross-Sectional Study

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Food and Nutrition Sciences 2025年第1期16卷 95-119页

作者： Nassaradine Macki Minawir Donatien Serge Mbaga Mahamat Béchir bernard Sodio Alpha Seydou Yaro cole Doctorale des Sciences et des Technologies du Mali Universit des Sciences des Techniques et des Technologies de Bamako (USTTB) Bamako Mali cole Suprieure des Sciences de la Sant Siantou Institut Universitaire Siantou Yaound Cameroon Facult des Sciences de la Sant humaine Universit de N'Djamna N'Djamna Chad Laboratoire dEntomologie-Parasitologie Facult des Sciences et Techniques (FST) Universit des Sciences des Techniques et des Technologies de Bamako (USTTB) Bamako Mali Malaria Research and Training Center Point G Facult de Mdecine et dOdontostomatologie (FMOS) Universit des Sciences des Techniques et des Technologies de Bamako (USTTB) Bamako Mali

Background: Malnutrition, a serious public health concern, is influenced by various factors. Objective: The study aims to explore malnutrition issues among infants under five years old in Guéra Province. Methods: The study used a cross-sectional design and a two-stage cluster sampling method to select participants. The study population was infants aged between 0 - 24 months. Data collection was done between June 2023 and September 2024;it included anthropometric measurements, blood analyses, and interviews. Anthropometric parameters were calculated using ENA for SMART software. Statistical analyses were performed by R Studio to investigate associations between different characteristics, using logistic regression models to identify risk factors. A p-value less than 0.05 was considered significant. Results: The study included 377 infants in eight villages in Guéra Province, Chad. The sample was predominantly girls (55.3%), with a median age of 16 months. Most infants (94%) were mixed-fed, and only 6% were exclusively breastfed. We found that 7.3% of children were globally malnourished, with higher rates in boys 9.6%. A significant disparity existed between boys and girls in global acute malnutrition (GAM) rates, with boys having a higher prevalence of 17.9%. A substantial proportion of Infants were underweight, with males 27.4%. Stunting was prevalent 20.1%. Several factors were associated with malnutrition, including gender, feeding practices, infectious diseases, and socioeconomic factors. Diarrhea, malaria, limited access to drinking water, and early diet diversification were significantly associated with malnutrition. Conclusion: Targeted interventions are necessary to address these issues and improve the nutritional status of children in the Guéra province.

关键词： Malnutrition Undernutrition Overnutrition Stunting Wasting Infant

Profitability of Fertilizer Use for Citrus Production in Teso Sub-Region, Eastern Uganda

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Agricultural Sciences 2025年第1期16卷 215-225页

作者： Onesmus Semalulu Patrick Makhosi Edgar Samuel Tinyiro Isaac Obongo Patricia Driciru Doreen Namamya Park Taeseon Cho Ilho Caroline Asio bernard Opio Emannuel Ikwap John Adriko National Agricultural Research Laboratories (NARL) Kampala Uganda National Crops Resources Research Institute (NaCRRI) Kampala Uganda Korean Partnership for Innovation of Agriculture (KOPIA) Uganda Centre Kampala Uganda Kumi District Administration Kumi Uganda Teso Fruits Cooperative Union Soroti Uganda Ngora District Local Government Ngora Uganda National Forestry Resources Research Institute (NaFORRI) Kampala Uganda

Citrus is an important commercial crop in Uganda, especially the Eastern region. however, in spite of the increasing regional demand, citrus productivity is still low, attributed to pest and diseases, soil moisture stress, and low soil fertility, among others. Efforts to improve soil fertility are limited by inadequate supply of organic fertilizers due to competing demands. In addition, there is inadequate information on inorganic fertilizer requirements for citrus production in Uganda. The objective of this study was to develop optimum fertilizer recommendations for citrus production for Eastern Uganda. The study was conducted in Teso region, Eastern Uganda. Fertilizer (NPK, 17:17:17) was randomly applied to hamlin, Valencia and Washington varieties with fertilizer and variety factorially arranged for each farm and citrus age range, replicated three times. Fertilizer rates were 0, 139, 278 and 556 kg NPK/ha for the 4 - 7-year old trees, and 0, 278, 556 and 1111 kg NPK/ha for the mature (8 years and above) trees. For a given variety, each fertilizer rate was applied onto three representative trees per farmer, six farmers per district. Results showed that yields and net profits were highest for variety hamlin, and nearly the same for varieties Washington and Valencia. Fertilizer application increased fruit yield and profits for both the 4 to 7-year and 8 and above-year-old trees, with highest yield and profitability values observed at 556 kg NPK/ha. These results suggest applying 556 kg NPK/ha to citrus per year as an optimum fertilizer rate for citrus production in Teso region. The fertilizer should be applied in smaller splits of 800, 600, and 600 grams per tree, applied in April, June, and August.

关键词： Citrus Varieties Climate-Smart Agriculture Cost-Effectiveness Fertilizer Recommendations Soil Fertility Management

The influence of pressure waves in tidal gravity records

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Geodesy and Geodynamics 2023年第1期14卷 15-25页

作者： bernard Ducarme Catholic University of Louvain Georges Lemaître Centre for Earth and Climate Research(ELI)Louvain-la-NeuveBelgium

For the reduction of atmospheric effects,observed gravity has initially been corrected by using the computed barometric admittance k of the in situ measured pressure,expressed in nms-2/hPa units and estimated by least squares ***,the local pressure changes alone cannot account for the atmospheric mass attraction and loading when the coherent pressure field exceeds a specific size,i.e.,with increasing *** overcome this difficulty,it is necessary to compute the total atmospheric effect at each station using the global pressure ***,the direct subtraction of the total gravity effect,provided by the models of pressure correction,is not yet satisfactory for S2 and other tidal components,such as K2 and P1,which include solar heating pressure *** paper identifies the origin of the problem and presents strategies to obtain a satisfactory ***,we set up a difference vector between the tidal factors of M2 and S2 after correction of the pressure and ocean tides *** vector,hereafter denoted as RES,presents the advantage of being practically insensitive to calibration *** minimum discrepancy between the tidal parameters of M2 and S2 corresponds to the minimum of the RES vector norm *** we adopt the hybrid pressure correction method,separating the local and the global pressure contribution of the models and replacing the local contribution by the pressure measured at the station multiplied by an admittance *** tested this procedure on 8 stations from the IGETS superconducting gravimeters network(former GGP network).For stations at an altitude lower than 1000 m,the value of dopt is always smaller *** discrepancy between the tidal parameters of the M2 and S2 waves is always lower than0.05% on the amplitude factors and 0.025° on the *** these stations,a correlation exists between the altitude and the value *** results at the three Central European stations Conrad,Pecny and Vienna are

关键词： Atmospheric pressure waves Atmospheric pressure correction in tidal records Atmospheric pressure models ERA5 and MERRA-2

A Fresh Look at the Structures of Nylons and the Brill Transition

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Advanced Fiber Materials 2021年第4期3卷 203-209页

作者： bernard Lotz Institut Charles Sadron CNRS and Universitéde Strasbourg23Rue du Loess67034 StrasbourgFrance

The common knowledge of the crystal structures of nylons dates back to the early 1950s with the work of Bunn and *** describes the packing of sheets made of hydrogen-bonded stems in an extended chain *** alpha phase structures have a specific powder X-ray diffraction pattern with reflections at 4.4Åand 3.7Å.On heating,reflections trans-form progressively and merge at≈4.2Åat the so-called“Brill transition”.Other diffraction patterns have been recorded for different types of nylons and thermal *** patterns were interpreted only as indicating the existence of“variants”of the alpha ***,neither their structure,nor the origin of the Brill transition were *** structural analyses and molecular modeling approaches have provided new insights in these long-standing structural ***“variants”feature chain conformations that are“pleated”.The Brill transition does not involve the standard extended chains of the alpha phase but corresponds to a dynamic interconversion(≈10^(10)/s)between mirror conformations of these pleated stems.

关键词： Nylons Crystal structures Phase transitions Brill transition

After Sendai:Is Africa Bouncing Back or Bouncing Forward from Disasters?

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International Journal of Disaster Risk Science 2016年第1期7卷 41-53页

作者： bernard Manyena International Disaster Management Humanitarian and Conflict Response Institute University of Manchester

The 187 countries that adopted the Sendai Framework for Disaster Risk Reduction 2015–2030 at the March 2015 UN World Conference on Disaster Risk Reduction included most African countries. Many developing regions of the world, particularly in Asia and Latin America, made considerable progress in implementing the previous hyogo Framework for Action 2005–2015. But,despite the fact that Africa is one of the regions most vulnerable and least resilient to disasters, which continue to be exacerbated by poverty, climate change, rapid urbanization, and structural transformation, it saw only slow progress. This article considers the challenges Africa faces in implementing the Sendai Framework and recommends that besides ‘‘Africanizing'' Sendai goals and strengthening the region's political commitment to disaster risk reduction(DRR), Africa should also develop a single framework that integrates DRR, sustainable development, climate change adaptation, and conflict prevention. Equally important is the need for a strong recognition that disasters are created endogenously as well as exogenously, and thus require local solutions and local investment.

关键词： Sub-Saharan Africa Climate change adaptation Disaster risk reduction Resilience Sendai framework Sustainable development

The apical plasma membrane of chitin-synthesizing epithelia

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Insect Science 2013年第2期20卷 139-146页

作者： bernard Moussian Animal Genetics Interfaculty Institute for Cell Biology University of Tubingen 72076 TEtbingen Germany

Chitin is the second most abundant polysaccharide on earth. It is produced at the apical side of epidermal, tracheal, fore-, and hindgut epithelial cells in insects as a central component of the protective and supporting extracellular cuticle. Chitin is also an important constituent of the midgut peritrophic matrix that encases the food supporting its digestion and protects the epithelium against invasion by possibly ingested pathogens. The enzyme producing chitin is a glycosyltransferase that resides in the apical plasma membrane forming a pore to extrude the chains of chitin into the extracellular space. The apical plasma membrane is not only a platform for chitin synthases but, probably through its shape and equipment with distinct factors, also plays an important role in orienting and organizing chitin fibers. here, I review findings on the cellular and molecular constitution of the apical plasma membrane of chitin-producing epithelia mainly focusing on work done in the fruit fly Drosophila melanogaster.

关键词： apical undulae cuticle extracellular matrix epidermis microvilli