检索结果-南通市图书馆

Enhanced dielectric performance of dy-substituted YMn2O5 for high-frequency applications

Progress in Natural science:Materials International 2021年第5期31卷 762-771页

作者： H.Chouaibi K.Khirouni E.dhahri laboratoire de Physique Appliquée Faculté des Sciences Université de Sfax laboratoire de Physique des Matériaux et des Nanomatériaux Appliquée à l'environnement Faculté des Sciences de Gabès Cité Erriadh Université de Gabès

The dielectric performances as well as the effects of dy3+ions content at A sites of YMn2O5(YMO) [x=0(YdM0)and x=0.4(YdM0.4)] polycrystalline samples were *** compounds were synthesized via sol-gel method.X-Ray diffraction and Raman measurements proved the high quality of the compounds that crystallized in an orthorhombic structure with the Pbam space ***,impedance spectroscopy and electrical modulus studies revealed that both samples exhibited a non-debye’s type of *** decrease of impedance for YdM0.4compared to the pure YdM0,may be attributed to the decrease in charge transfer *** the fit of impedance spectra,they confirmed that both compounds were simultaneously capacitive and ***,the activation energies obtained from Modulus and complex impedance were proven to be neighboring,suggesting that the relaxation process refers to electron *** each compound,the evolution of ε’and tan & with temperature indicated a clearer relaxor behavior,namely the existence of two *** first one detected at low temperature is related to the charge carriers hopping between Mn3+and Mn4+and the second at high temperature is associated with oxygen *** reduced hopping rate with dy3+substitution for Y3+ions at A sites is responsible for the decrease in dielectric constant and dielectric *** significant findings demonstrate that these materials can be invested in a fruitful use in UV photo-detector and power applications in high frequency as microwave,millimeter wave signal processing,for civilian,military and space applications.

关键词： Multiferroic Relaxation phenomenon High dielectric constant Relaxor behavior

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

First principles study of structural, electronic and magnetic properties of snGe_n^((0, ±1)) (n = 1–17) clusters

引用

Journal of semiconductors 2018年第4期39卷 1-13页

作者： soumaia djaadi Kamal Eddine Aiadi sofiane Mahtout laboratoire de developpement des energies nouvelles et Renouvelables en Zones Aride Universite de Ouargla 30000 Ouargla Algeria laboratoire de physique Theorique Faculte des Sciences Exactes Universite de Bejaia 06000 Bejaia Algeria

The structures, relative stability and magnetic properties of pure Gen＋l, neutral cationic and anionic sn- Gen （n = 1-17） clusters have been investigated by using the first principles density functional theory implemented in sIEsTA packages. We find that with the increasing of cluster size, the Gen＋1 and snGen（1, ±1） clusters tend to ad- opt compact structures. It has been also found that the sn atom occupied a peripheral position for snGen clusters when n 〈 12 and occupied a core position for n 〉 12. The structural and electronic properties such as optimized geometries, fragmentation energy, binding energy per atom, HOMO-lUMO gaps and second-order differences in energy of the pure G%＋1 and snGen clusters in their ground state are calculated and analyzed. All isomers of neutral snG% clusters are generally nonmagnetic except for n = 1 and 4, where the total spin magnetic moments is 2μb. The total （dOs） and partial density of states of these clusters have been calculated to understand the origin of peculiar magnetic properties. The cluster size dependence of vertical ionization potentials, vertical electronic affinities, chemical hardness, adiabatic electron affinities and adiabatic ionization potentials have been calculated and discussed.

关键词： dFT calculations sn-Ge clusters structural properties electronic properties magnetic properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Photovoltaic waste management in sub-saharan Africa:current practices in Burkina Faso

引用

Waste disposal and sustainable Energy 2024年第2期6卷 271-282页

作者： Kodami Badza Yrebegnan Moussa soro Marie sawadogo laboratoire energies Renouvelables et EfficacitéEnergétique Institut International d'Ingenierie de I'Eau et de I'Environnement(2iE)01 BP 594 OuagadougouBurkina Faso

sub-saharan Africa is witnessing a proliferation of photovoltaic(PV)waste due to the increasing number of solar PV power *** waste(panels,batteries,electrical cables,mounting structures,and inverters)consists of elements such as mercury,cadmium,chromium,lead,copper,aluminum,fluorinated compounds,and plastics that are toxic to human health and the environment if a proper management system is not *** many studies worldwide have focused on PV waste management,very few have been conducted in sub-saharan *** study aims to investigate the current PV waste management system in Burkina Faso,determine stakeholder profiles,and propose strategies to enhance the existing *** research,interviews,questionnaires,and field visits were used in the *** survey showed that young people,mainly under 30 years of age and with a primary education,dominate(70%)in terms of PV waste collection and repair activities,while the more technical recycling and export activities are carried out mainly(88%)by stakeholders older than 40 years and with a secondary education(60%).Among the older stakeholders,100%are aware of the hazardous nature of PV waste,whereas 36%are young *** an environmental perspective,the main source of contamination observed is the release of lead-rich sulfuric acids into water and soil during the collection and repair *** the recycling of batteries and electrical cables,toxic fumes are emitted into the air,and recycling residues rich in toxic substances are *** reduce risks to human health and the environment when managing PV waste,the introduction of legislation,the multiplication of collection points and appropriate infrastructures,the training and awareness-raising of stakeholders,and the extended responsibility of manufacturers are *** on the economic feasibility of setting up formal management structures are needed to complete this work.

关键词： Photovoltaic waste sub-saharan Africa Waste management Recycling Batteries Incineration

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Optimization of Rubber seed Oil Transesterification to Biodiesel Using Experimental designs and Artificial Neural Networks

引用

Green and sustainable Chemistry 2018年第1期8卷 39-61页

作者： Konan Edmond Kouassi Abollé Abolle Abolle Kouassi Benjamin Yao david Boa Kopoin Adouby Patrick drogui Rajeshwar dayal Tyagi laboratoire de procédés industriels de Synthèse de l’Environnement et des Energies Nouvelles Groupe des Procédés et Environnement Institut National Polytechnique Félix Houphou&#235 t-Boigny Yamoussoukro C&#244 te d’Ivoire laboratoire de Thermodynamique et Physico-Chimie du Milieu UFR Sciences Fondamentales et Appliquées Université Nangui Abrogoua Abidjan C&#244 te d’Ivoire Institut National de la Recherche scientifique (INRs-Centre Eau Terre et Environnement) Université du Québec Québec Canada

The development of biofuels is driven both by concern about the greenhouse effect and by interest in the opportunities for exploitation of biomass of agricultural origin. In order to improve the yield and quality of biodiesel through modeling and optimization, several studies are in progress. In this paper, biodiesel produced from rubber seed oil in the homogeneous transesterification is studied using a Plackett-Burman experimental design, a full factorial design, a central composite design and an Artificial Neural Network (ANN) coupled with a Genetic Algorithm (GA).Variables such as temperature, stirring speed, reaction time, type of alcohol, and type of catalyst are studied to obtain the best specific gravity and kinematic viscosity. Type of alcohol and type of catalyst have the greatest effect on the two responses, with ethanol (alcohol) and sulphuric acid (catalyst) producing the best results. The specific gravity and kinematic viscosity changes recorded during the transesterification process followed the first and second order polynomial models, respectively. The ANN coupled with GA was used to optimize the two responses simultaneously. Global optimal values of specific gravity (0.883) and kinematic viscosity (6.76 cst) were recorded when a temperature of 90°C, a stirring speed of 305 rpm, and a treatment time of 141 min were imposed.

关键词： Rubber seed Oil Biodiesel Transesterification specific Gravity Kinematicviscosity

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Experimental study of a solar Thermal Incubator Using a Phase-Change Material for Off-Grid Use

引用

Open Journal of Applied sciences 2024年第9期14卷 2471-2481页

作者： Yéouélé Thio Bati Ernest Boya Bi Ekoun Paul Magloire Koffi Prosper Gbaha laboratoire des procds industriels de synthse de lEnvironnement et des Energies Nouvelles Institut National Polytechnique Flix Houphout-Boigny Yamoussoukro Cte dIvoire

The aim of this study was to provide a simple, easy-to-use incubation system for small-scale rural poultry farmers far from the electricity grid. To this end, a naturally ventilated solar thermal incubator was built and experimentally tested. A U-shaped evacuated tube collector and a wooden crate holding 50 eggs were used to build the solar thermal incubator. Water was used as the heat transfer fluid, and an EPCM was integrated into the incubation chamber for operation at night or when the sun was hidden. The heat generated by the solar collector and stored in the heat transfer fluid is transported to the incubation chamber by thermosiphon to heat the chamber. Temperature and humidity probes powered by a solar panel were placed at various locations to monitor the thermo-hygrometric efficiency of the incubation system. The incubator, heated by natural convection, proved to function normally, and the incubation chamber was maintained throughout the incubation period within a temperature range of 35.53˚C to 39.53˚C and relative humidity averaging 49.4% to 68.5%. The experiment was carried out by introducing 30 eggs and the results of the experimental study showed that the incubator’s efficiency was 87%. The performance tests gave a fertility rate of 93% and a hatching rate of 93%, i.e. 28 fertile eggs and 26 hatched eggs, respectively.

关键词： solar Incubator Vacuum Tube Collector Encapsulated PCM Poultry Eggs

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Elimination of Carbon, Nitrogen and Phosphorus in domestic Wastewater through a series of Anaerobic and Aerobic Reactors for a developing Country like Benin

引用

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 procédés 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 Appliquée (lERCA) Ecole Polytechnique d’Abomey-Calavi (EPAC) Université d’Abomey-Calavi (UAC) Cotonou Bénin

Waste water treatment in order to preserve water resources is one of the major concerns in developing countries. This study aims to test the operating effectiveness of a pilot designed on a basis of several laboratory experiments, which consists of an anaerobic and aerobic pond in series. The test was performed through monitoring global parameters of pollution. The results of the analysis of these parameters indicate an elimination of 91% of suspended solids, 68% of COd, 77% of BOd5, 61% of nitrate and 81% of phosphorus. It was also noticed that the anaerobic pond removes most, carbonaceous organic materials and especially suspended matters;and the aerobic pond most, nitrogen and especially phosphorus. This study reveals the effectiveness of the series connection of an anaerobic and aerobic pond for domestic wastewater treatment.

关键词： Wastewater Anaerobic/Aerobic Pond Pilot

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Optimization of Preparation Conditions of Activated Carbons Based on the shells of Ricinodendron heudoltii

引用

Journal of Materials science and Chemical Engineering 2022年第10期10卷 40-58页

作者： Kouakou Yao Urbain Karidioula daouda Zran Vanh Eric-simon Trokourey Albert Yao Kouassi Benjamin drogui Patrick UFR sciences et Technologies Université de Man Man C&#244 te d’Ivoire laboratoire de Constitution et Réaction de la Matière (lCRM) à l’UFR ssMT Université Félix Houphou&#235 t-Boigny (UFHB) de Cocody Abidjan C&#244 te d’Ivoire laboratoire des procédés industriels de synthèse de l’environnement et des energies nouvelles (lAPIseN) de l’Institut National Polytechnique Félix Houphouë t Boigny de Yamoussoukro Yamoussoukro C&#244 te d’Ivoire Institut National de la Recherche scientifique Département INRS-Eau Terre et Environnement Université du Québec Québec Canada

The purpose of this work is to prepare better activated carbons from the shells of Ricinodendron Heudelotii by chemical activation with sulfuric acid (H2sO4) and sodium hydroxide (NaOH). The process was optimized by a... 详细信息

The purpose of this work is to prepare better activated carbons from the shells of Ricinodendron Heudelotii by chemical activation with sulfuric acid (Hsub>2sub>sOsub>4sub>) and sodium hydroxide (NaOH). The process was optimized by a full factorial design (2sup>Ksup>) based on the analysis of the external specific surface area of sixteen (16) activated carbons prepared according to the parameters of the preparation. This active analysis reveals that under the preparation conditions, good carbons are obtained for a sodium hydroxide concentration equal to 1 M, an impregnation time of 24 h and carbonization at 500˚C for 1 h. The external specific surface of this carbon is 358 msup>2sup>sup> sup>•sup>sup> gsup>-1sup>. The characteristics of this prepared carbon are as follows: a pH at zero point charge (pHpzc) of 8.2, a predominantly amorphous structure, a basic character and a low ash content (4.2%). It also has surface functions;the lactonic and carbonyl groups (C=O) at 1600 cmsup>-1sup> and the carboxylate groups (O-H or C-O) at 1340 cmsup>-1sup>.

关键词： Activated Carbons Ricinodendron Heudelotii Chemical Activation Optimization specific surface

来源：

维普期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

dimensioning of an Anaerobic digester for the Treatment of Chicken Manure and for the Production of Biogas: The Case study of a Chicken Farm in Yaokokoroko (Côte d’Ivoire)

引用

Green and sustainable Chemistry 2022年第4期12卷 91-103页

作者： Kouakou Adjoumani Rodrigue Ehouman Ahissan donatien Konan Affoué Tindo sylvie Teki Adjoba Marie-Emmanuelle Kouadio Marc Cyril Adou Kouakou Eric Konan Gbangbo Remis laboratoire de Thermodynamique et de Physico-Chimie du Milieu (lTPCM) UFR Sciences Fondamentales Appliquées Université Nangui Abrogoua Abidjan C&#244 te d’Ivoire département de Formation et de Recherche des sciences de la Terre et des Ressources Minières Ressources en Eaux et Risques Hydrologiques Institut National Polytechnique Felix Houphou&#235 t-Boigny Yamoussoukro C&#244 te d’Ivoire Institut de Recherche sur les energies nouvelles Université Nangui Abrogoua Abidjan C&#244 te d’Ivoire laboratoire des procédés industriels de Synthèse de l’Environnement et des énergies Nouvelles (LAPISEN) Institut National Polytechnique Houphou&#235 t-Boigny Yamoussoukro C&#244 te d’Ivoire

This study allowed us to highlight the level of pollution of a BAYA River water near several poultry farms and the sizing of an anaerobic digester that will be able to treat chicken manure from a poultry farm (BRIN FOUNdATION). To evaluate this pollution, the parameters such as ammonium (NHsub>4sub>sup>+sup>), Phosphate (POsub>4sub>sup>3-sup>), Biochemical Oxygen demand (dBOsub>5sub>) and Nitrate (NOsub>3sub>sup>-sup>) were determined. For sampling point P1, the concentrations in mg/l of these parameters are (25.00 ± 4.25), (0.40 ± 0.20), (98.00 ± 6.35) and (96.00 ± 5.35), respectively. On the other hand, for sampling point P2, the concentrations in mg/l of these parameters are respectively (33.00 ± 9.05), (0.70 ± 0.12), (123 ± 7.13) and (93 ± 7.10). These values indicate a strong organic pollution of the BAYA River. The determination of the different concentrations of the organic pollution parameters allowed us to evaluate the degradation and the quality of the water of the BAYA River water, by the poultry activity. However, considering the physicochemical properties of the waste (chicken manure), which is the main source of organic pollution, we have considered an energy recovery through the production of biogas. This requires the design, sizing, and implementation of an anaerobic digester in a poultry farm. Therefore, the project would require the construction of an adapted masonry type anaerobic digester with a capacity of 10 msup>3sup>.

关键词： Biogas Organic Pollution surface Water Biodigester Chicken Manure Anaerobic digestion

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Assessment of Heavy Metals Contamination in sediments of the Vridi Canal (Côte d’Ivoire)

引用

Journal of Geoscience and Environment Protection 2016年第10期4卷 65-73页

作者： Kouakou Adjoumani Rodrigue Benjamin Yao Albert Trokourey Adouby Kopoin laboratoire de Chimie Physique Université Félix Houphou&#235t Boigny Abidjan C&#244te d’Ivoire laboratoire des procédés industriels de synthèse de l’Environnement et des Energies Nouvelles Institut National Polytechniques Felix Houphou&#235t Boigny (INPHB) Yamoussoukro CLaboratoire de Chimie Physique Université Félix Houphou&#235t Boigny Abidjan C&#244te d’Ivoirete d’Ivoire

The concentrations of cadmium, copper, lead and zinc in sediment samples from the Vridi Canal (Harbour area of economic capital of Cote d’Ivoire) were determined to evaluate the level of contamination. All metal concentrations in sediment samples, except Cu, were greater than the concentration of Upper Continental Crust (UCC). sediment pollution assessment was undertaken by using Enrichment Factor (EF), geoaccumulation index (Isub>geosub>) and Pollution load Index (PlI). The enrichment factor (Cd: EF = 20.04;Pb: EF = 3.43;Zn: EF = 1.56) and géoaccumulation index (Cd: Isub>geosub> = 4.29;Pb: Isub>geosub> = 1.81) showed that the sediments were polluted. The Pollution load Index (PlI > 1) indicated that the sediments of the studied area were heavily contaminated. Based on the comparison with sediment quality guidelines, the concentrations of cadmium, lead and zinc would be toxic to one or more species of aquatic organisms living in the sediments.

关键词： Heavy Metals Vridi Canal Contamination

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Novel Mannich Bases of Benzimidazole derivatives: An Antibacterial study of Environmental Bacterial strains

引用

Advances in Biological Chemistry 2023年第5期13卷 182-191页

作者： Evrard Ablo Ouehi dosso Bakary Coulibaly Kouassi Franscesco Adingra Penayori Marie-Aimée Coulibaly Armand Patrick Achi Tchambaga etienne Camara souleymane Coulibaly siomenan Coulibali laboratoire de Constitution et Réaction de la Matière UFR Sciences des Structures de la Matière et Technologie Université Félix Houphou&#235t-Boigny de Cocody Abidjan C&#244te d’Ivoire laboratoire des procédés industriels de synthèse de l’Environnement et des énergies Nouvelles (LAPISEN) Institut National Polytechnique Félix Houphou&#235t-Boigny Yamoussoukro C&#244te d’Ivoire laboratoire d’Agrovalorisation Département de Biochimie-Microbiologie UFR Agroforesterie Université Jean Lorougnon Guédé Daloa C&#244te d’Ivoire

A previous study was conducted on the synthesis and antibacterial evaluation of Mannich bases of 2-(thioalkyl)-1H-methylbenzimidazole derivatives. The results of this study showed that certain 2-(thioalkyl)-1H-methylbenzimidazole and 2-(thioalkyl)-methyl-1-(piperidin-1-ylmethyl)benzimidazole derivatives possess antibacterial activities against clinical strains, such as Escherichia coli, Klebsiella pneumonia (Gram-negative bacteria), staphylococcus aureus and Pseudomonas aeruginosa (Gram-positive bacteria). Following these favorable results, we extended the antibacterial evaluation of this series of molecules to environmental strains. The aim of this study was to assess the impact of the methyl-piperidine group fixed at position-1 of this new series of benzimidazoles on the antibacterial activity of environmental strains. In addition, we first evaluated the antibacterial activity of four 2-(thioalkyl)methylbenzimidazole derivatives and then that of five 2-(thioalkyl)-methyl-1-(piperidin-1-ylmethyl) benzimidazole derivatives. This study allowed us to show that compounds 1d and 1e could inhibit bacterial growth in vitro of the Enterobacteria P1 strain with inhibition diameters of 17.3 ± 0.6 mm and 10 ± 0.0 mm, respectively. However, addition of methyl-piperidinyl in this series showed that five (5) of 2-(thioalkyl)-methyl-1-(piperidin-1-ylmethyl) benzimidazole derivatives had an inhibitory effect on the in vitro growth of bacterial strains used except on Enterobacteria P2 with inhibition diameters between 10.0 ± 0.8 mm and 27.9 ± 1.4 mm. The introduction of the methyl-piperidinyl group at the 1-position of 2-(thioalkyl)-1H-methylbenzimidazole derivatives greatly improved the antibacterial activity against environmental bacteria such as Escherichia coli A1, A2, A3, and A4 and two Enterobacteria P1.

关键词： Methylbenzimidazole derivatives Inhibit Bacterial Growth Mannich Base Enterobacteria Escherichia coli

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：