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Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.sardar M.D.Hossain M.s.sikder M.N.I.Khan M.r.rahman Physics Discipline Khulna UniversityKhulna9208Bangladesh Department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Department ofComputer science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh Material science Division Atomic Energy CentreDhaka1000Bangladesh

spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XrD),Fourier transform infrared spectroscopy(FTIr),field emission scanning electron microscopy(FEsEM),energy dispersive X-ray(EDX),vibrating sample magnetometer(VsM),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XrD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTIr analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FEsEM images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EDX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites raree arths Coercivity Permeability EDX resistivity

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New Approach to rock Classification Based on sparse representations

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Open Journal of Applied sciences 2024年第1期14卷 145-158页

作者： Wognin Joseph Vangah Bi g. Théodore Toa Alico Nango Jerôme Ouattara sie Alain Clément Unité de recherche et d’expertise Numérique (UrEN) Université Virtuelle de C&#244te d’Ivoire (UVCI) Abidjan C&#244te d’Ivoire UFr sciences et technologique Département de Physique Université polytechnique de Man (UPM) Man C&#244te d’Ivoire Classe Préparatoire des grandes Ecoles (CPgE) Université de San Pédro (USP) San Pédro C&#244te d’Ivoire Institut National Polytechnique Houphouë t (INPHB) Yamoussoukro C&#244te d’Ivoire Laboratoire Angevin de recherche en Ingénierie des systèmes (LArIs) Institut Universitaire de Technologie (IUT) Université d’Angers Angers France

In geology, classification and lithological recognition of rocks plays an important role in the area of oil and gas exploration, mineral exploration and geological analysis. In other fields of activity such as construction and decoration, this classification makes sense and fully plays its role. However, this classification is slow, approximate and subjective. Automatic classification curbs this subjectivity and fills this gap by offering methods that reflect human perception. We propose a new approach to rock classification based on direct-view images of rocks. The aim is to take advantage of feature extraction methods to estimate a rock dictionary. In this work, we have developed a classification method obtained by concatenating four (4) K-sVD variants into a single signature. This method is based on the K-sVD algorithm combined with four (4) feature extraction techniques: DCT, gabor filters, D-ALBPCsF and g-ALBPCsF, resulting in the four (4) variants named K-gabor, K-DCT, KD-ALBPCsF and KD-ALBPCsF respectively. In this work, we developed a classification method obtained by concatenating four (4) variants of K-sVD. The performance of our method was evaluated on the basis of performance indicators such as accuracy with other 96% success rate.

关键词： rock recognition Dictionary signature Color Texture K-sVD Variants KD-ALBPCsF Et Kg-ALBPCsF

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Optimising Energy Consumption in sD-DCN Networks (software Defined-Data Center Network)

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Open Journal of Applied sciences 2024年第8期14卷 2223-2235页

作者： Narcisse Tahi Etienne soro Pacôme Brou Olivier Asseu UMrI sTI INPHB INPHouphout Boigny Yamoussoukro Cte dIvoire Ecole suprieure Africaine des Technologies de lInformation et de la Communication (EsATIC) LASTIC Laboratory of ESATIC Abidjan Cte dIvoire

Over the last decade, the rapid growth in traffic and the number of network devices has implicitly led to an increase in network energy consumption. In this context, a new paradigm has emerged, software-Defined Networking (sDN), which is an emerging technique that separates the control plane and the data plane of the deployed network, enabling centralized control of the network, while offering flexibility in data center network management. some research work is moving in the direction of optimizing the energy consumption of sD-DCN, but still does not guarantee good performance and quality of service for sDN networks. To solve this problem, we propose a new mathematical model based on the principle of combinatorial optimization to dynamically solve the problem of activating and deactivating switches and unused links that consume energy in sDN networks while guaranteeing quality of service (Qos) and ensuring load balancing in the network.

关键词： DCN Optimisation Energy Consumption Qos sDN

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summary of a Life in Observational Ultraviolet/Optical Astronomy

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research in Astronomy and Astrophysics 2024年第1期24卷 1-43页

作者： Donald g.York Department of Astronomy and Astrophysics The University of Chicago5801 South Ellis Ave.Chicago 60637ILUSA

I reminisce on my early life in section 1;on my education in sections 2 and 3;on the years at Princeton as a research astronomer in section 4;on the years on the faculty at Chicago in section 5;on research on Diffuse Interstellar Bands(DIBs) in section 6;on construction of the 3.5 m telescope at Apache Point Observatory(APO)in section 7;on work on the sloan Digital sky survey(sDss) in section 8;on work in public education in Chicago in section 9;and on my travels in section 10. My main science research is of an observational nature,concerning galactic and intergalactic interstellar gas. Highlights for me included my work on the orbiting telescope Copernicus, including the discovery of interstellar deuterium;early observations of absorption associated with fivetimes ionized oxygen;and discoveries concerning the phases of gas in the local interstellar medium, based on previously unobservable interstellar UV spectral lines. With other instruments and collaborations, I extended interstellar UV studies to the intergalactic cool gas using quasi-stellar object QsO absorption lines redshifted to the optical part of the spectrum;provided a better definition of the emission and morphological character of the source of absorption lines in QsO spectra;and pursued the identification of the unidentified DIBs. For several of these topics, extensive collaborations with many scientists were essential over many years. The conclusions developed slowly, as I moved from being a graduate student at Chicago, to a research scientist position at Princeton and then to a faculty position at Chicago. At each stage of life, I was exposed to new technologies adaptable to my science and to subsequent projects. From high school days, I encountered several management opportunities which were formative. I have been extremely fortunate both in scientific mentors I had and in experimental opportunities I encountered.

关键词： Interstellar medium(IsM) Nebulae (galaxies:)quasars:absorption lines ultraviolet:stars

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Ovarian Tumors in senegalese Women: Impact of D-Loop Mutations between Healthy and Cancerous Tissues

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Open Journal of genetics 2024年第2期14卷 37-46页

作者： rouguiyatou Ka Fatimata Mbaye Bineta Kénéme Mbacké sembène genomics Laboratory Department of Animal Biology Faculty of Science and Technology Cheikh Anta Diop University Dakar Senegal

In senegal in particular, ovarian cancer, which is one of the most common gynecological cancers, accounts for 2.8% of deaths. The most important risk factor is genetic, with 10% of cases occurring in a context of genetic predisposition. The sequencing of the human genome, which has led to the discovery of millions of sequence variations, makes it possible to study variations within sequences. These variations are limited to single Nucleotide Polymorphisms (sNPs) and this common form of polymorphism occurs approximately every 1000 bases in the human genome and 1.8 million sNPs are currently listed according to [1]. The aim of this study is to gain a better understanding of the impact of mutations in the D-loop region of mtDNA on ovarian cancer in senegalese women. This study involved searching for mutations in our study population after DNA extraction and sequencing. Mutations were found after a comparison of our sequences with the Cambridge reference sequence (NC_012920). The mutations found in the DNA studied extend from position 7 to position 16568 and most of these mutations are located in the hypervariate zones (HV1 and HV2). Heteroplasmy with three mutant alleles was also found in certain variants. Common mutations were found in both healthy and cancerous tissues, with almost identical frequencies in both types of tissue. This enabled us to understand the spread of tumor cells throughout the ovary.

关键词： Ovarian Cancer Mutations D-Loop Heteroplasmy

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Flow Dynamics during the Hydrocarbon Exploitation for Prevention and Management of Water Venues in Oil Field: A study Case of Crystal Field in Badila/Chad

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International Journal of geosciences 2024年第5期15卷 433-448页

作者： Issakha Tidjani Djimet Huguette Christiane Emvoutou Nicodème Djiedeu Jean-Pierre Nguenang Laboratory of Fundamental Physics Department of Physics Faculty of Science University of Douala Douala Cameroon Laboratory of geosciences Natural Resources and Environment Department of Earth Sciences Faculty of Science University of Douala Cameroon

The southern part of the Lake Chad basin is under the gas and oil petroleum industry due to its hydrocarbon potential for about twenty years. This project stands out as the main challenges of the hydrocarbon production and the management of fluxes particularly the groundwater venues. A comprehensive study is thus conducted to develop a dynamic and analytic model for diagnosing the production performances with a particular view on the management of groundwater venues. The three main concerned reservoirs subdivided on subunits evidence their proper characteristics. The porous media, their densities, the internal flows and the water injection techniques such as water flooding were thus adopted. The oil viscosity variability within the reservoirs creates different levels of mobility between water and oil, highlighting the challenges of water management. The material balance model and the behavior of the well analysis were taken in consideration within the identified aquifer, emphasizing the importance of keeping the pressure through injection. The control of water productions, the management of the reservoir, the well strategical position and the specific completions lead to the model functioning. In addition, the CO log and the Pulsed Neutron indicate their limitations as a result of the water salinity and the porosity of the aquifer. The management of groundwater venues at Badila requires various approaches throughout the lifetime of the Crystal field such as the data acquisition and remediation actions and prevention, under a permanent monitoring of the dynamic fluxes in the reservoirs.

关键词： groundwater Venues Analytic and Dynamic Model Water Flooding Optimization of Production

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Influence of Microorganisms Effective against Basal rot and on Agronomic Parameters of Onion [Allium cepa L. (Amaryllidaceae)]

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Journal of Agricultural Chemistry and Environment 2024年第3期13卷 282-299页

作者： Henriette Doukahonon guigui Bi Zaï Pacôme Zaouli Alain serge Coulibaly Juliette Ky Dedi Training and research Unit of sciences of Nature Laboratory of Biology and Improvement of Plant Production Nangui Abrogoua University Abidjan Cte dIvoire Department of Plant Biology Training and Research Unit (UFR) of Biological Sciences Peleforo Gon Coulibaly University Korhogo Cte dIvoire

Onions are a horticultural crop of great economic, dietary and medicinal importance, and are highly prized by the Ivorian population. However, production remains low, due to a number of constraints, including parasitic attacks. The most frequent is fusariosis caused by Fusarium sp., a pathogen that causes enormous damage to onion crops. Faced with these attacks, chemical control appears to be ineffective, with consequences for human health and the environment. This is why the search for effective alternative methods that respect the environment and human health is so necessary. It is in this context that this study was carried out, with the general aim of controlling fusarium wilt in onion crops, with a view to improving onion production in Ivory Coast through the use of effective microorganisms. The experimental set-up used for this purpose was a fisher block with complete randomization, comprising three replicates. A fungal spore concentration of 106 spore/mL of Fusarium sp., three doses (1%;2.5% and 5% v/v) of EM and one dose of a chemical fungicide (30 mL/16L) were tested on young onion plants. Each block consisted of nine sub-plots with nine treatments. Health parameters (incidence and severity) and agronomic parameters (growth and yield) were assessed. Microbiological analysis of the EM revealed the presence of nine morphotypes of Trichoderma sp., Aspergillus clavatus, Aspergillus flavus, Aspergillus sp., Penicillium sp., rhizopus sp., lactic acid bacteria of the Bacillus family and the yeast saccharomyces cerevisiae. Field experimentation showed that the 5% EM microbial solution reduced the incidence and severity of fusariosis compared with the chemical fungicide, and proved to be the best. This dose reduced yield losses by 7.14%, while improving onion growth and yield by over 5%. The results demonstrated the ability of the EM solution to effectively control the causal agent of basal rot in onion crops.

关键词： Basal rot Effective Microorganisms (EM) Fusarium sp. Onion

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Distribution, Mobility, and Health risks Assessment of Trace metals in river sediments from Intense Agricultural Activity Areas in West Africa

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Journal of Materials science and Chemical Engineering 2024年第8期12卷 12-42页

作者： Ahbeauriet Ahmed Ouattara Maley-Pacôme soro Albert Brou Kouadio Horo Koné Albert Trokourey Dpartment des sciences et Technique Universit Alassane Ouattara Bouak Cte dIvoire Laboratoire de Thermodynamique et de Physico-Chimie du Milieu Universit Nangui Abrogoua Abidjan Cte dIvoire Laboratoire de Chimie Physique Universit Flix Houphout Boigny Abidjan Cte dIvoire

The economy of West African countries is mainly based on agriculture. However, the trace metal(loid)s contamination status in rivers is relatively unknown in the region. In this work, 45 surface sediments collected from the Bandama, Comoé, and Bia rivers in south and south eastern Côte d’Ivoire (West Africa), were analyzed for total metal concentrations and chemical speciation. The results showed that the river sediments were considerably contaminated by Cd and moderately contaminated by As, Cu, Pb, and Zn. significant spatial variations were observed among the stations but not between the rivers. metals Cd and Cu were likely to cause more ecological risks. The speciation analysis unravelled that the metal(loid)s partitioned mainly in the residual fraction, with the potential mobile fraction varying from 14% to 28%. The study calls for establishment of strict policies relative to the application of fertilizers and agrochemicals and mining activities to protect the environment and human health risks.

关键词： river sediment Trace metal (Loid)s Multivariate Analysis Potential Ecological risk Assessments sequential Extraction geochemical Indices

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小渔村里的Elkano 探访西班牙传奇烤鱼餐厅

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环球人文地理 2024年第17期 74-79页

作者：王洁 Elkano LACrème

在西班牙巴斯克地区的一个小渔村里，藏着一家餐厅，它与巴黎世家并列为渔村的双生瑰宝，吸引着世界各地的游客前去一探究竟。西班牙风情只是热情奔放的弗拉明戈舞和斗牛？西班牙海滩就是清澈碧蓝的地中海式海滩？西班牙美食只有海鲜饭...

在西班牙巴斯克地区的一个小渔村里，藏着一家餐厅，它与巴黎世家并列为渔村的双生瑰宝，吸引着世界各地的游客前去一探究竟。西班牙风情只是热情奔放的弗拉明戈舞和斗牛？西班牙海滩就是清澈碧蓝的地中海式海滩？西班牙美食只有海鲜饭？如果你对以上三个问题的回答都是“YEs”，那不得不说：你对西班牙的认识过于简单啦！

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gastrointestinal Ulcers Treatment: Plants and recipes Used by Herbalists of Abomey-Calavi and Cotonou Districts, southern Benin

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American Journal of Plant sciences 2024年第9期15卷 699-725页

作者： Brice Dangnon Durand Dah-Nouvlessounon sêmassa Mohamed Ismaël Hoteyi Abdelmalick Abdelrahman Moubachar Abdelkerim Mahamat Nicodème Worou Chabi sina Haziz Farid Baba-Moussa Adolphe Adjanohoun Lamine Baba-Moussa Laboratory of Biology and Molecular Typing in Microbiology Department of Biochemistry and Cell Biology Faculty of Science and Technology University of Abomey-Calavi Cotonou Benin Unit of Biochemistry and Molecular Markers in Nutrition Laboratory of Research in Applied Biology Polytechnic School of Abomey-Calavi University of Abomey-Calavi Cotonou Benin Laboratoire de Microbiologie et de Technologie Alimentaire Faculty of Science and Technology University of Abomey-Calavi Cotonou Benin Institut National des recherches Agricoles du Bnin Cotonou Benin

This study set out to identify plants and recipes used by herbalists in the municipalities of Abomey-Calavi and Cotonou to treat gastrointestinal ulcers and to characterize the distribution of their knowledge. An ethno-pharmacological survey was carried out in which informants who agreed freely were interviewed using a semi-structured questionnaire. A total of 85 herbalists were surveyed. The data were processed with Microsoft Excel to calculate the relative frequencies of citation of the various species mentioned by the herbalists and various indices including simpson’s Index were adapted to test the distribution of their knowledge. Multiple regression and correspondence analysis were performed using r studio. Our results revealed that the Dendi, Ifè and Mina, all equitable in their knowledge of anti-ulcer plants, are likely to know more than the other ethnic groups. On the other hand, respondents practicing Islam are more likely to know many antiulcer plants than those practicing Vodoun and Christianity. This constant distribution of knowledge of anti-ulcer plants among the Dendi, Ifè and Mina, three different ethnic groups seems normal and attests to the fusion between these different ethnic groups in view of this knowledge. A total of 70 anti-ulcer recipes, made from 71 species of medicinal plants or non-floristic resources were recorded. Vitellaria paradoxa, Parkia biglobosa and Ocimum gratissimum were the top 03 most frequently cited in descending order of frequency. All the species cited are grouped into 44 botanical families among which the Fabaceae, Lamiaceae and sapotaceae were strongly represented. Benin’s flora abounds in a diversity of medicinal plant species known to herbalists in Abomey-Calavi and Cotonou for the treatment of gastrointestinal ulcers. The results of this study constitute a good archive for the selection of plant species for in-depth studies with a view to formulating improved traditional medicines for gastrointestinal ulcers.

关键词： gastrointestinal Ulcer Ethnomedicine Herbalist Nature Plant Material

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