检索结果-南通市图书馆

Performance Evaluation of Solar Chimney Draft: Application to Ventilation

Smart Grid and Renewable Energy 2024年第4期15卷 107-122页

作者： boukaré ouedraogo Adama ouedraogo Arouna Kabore Kalifa Palm Dieudonné Joseph Bahiebo Laboratoire dEnergies Thermiques Renouvelables (LETRE) Universit Joseph KI-ZERBO: UFR/SEA Ouagadougou Burkina Faso Laboratoire de Chimie Analytique Physique Spatiale et Energtique (LACAPSE) Universit Norbert ZONGO Koudougou Burkina Faso Centre Universitaire Polytechnique de Kaya (CUP-Kaya) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratoire des Systmes dEnergie Renouvelable et Environnement Institut de Recherche en Sciences Appliques et Technologies (IRSAT) Centre National de la Recherche Scientifique et Technologique (CNRST) Ouagadougou Burkina Faso

Ventilation is one of the factors contributing to energy consumption in buildings and food preservation. The solar chimney proves to be an alternative for reducing conventional energy consumption. Thus, in this study, the performance of a solar chimney with two active faces for thermally drawing air from a chamber for preserving agri-food products was evaluated. These performances were experimentally assessed through data measurements: temperatures and velocities within the chimney, and their analysis using Excel and MATLAB. The obtained results were compared with those from literature to verify their validity. From this study, it is found that the maximum temperature at the chimney outlet reaches 49.4˚C with an average value of 43.7˚C. Additionally, the heating evolution of the chimney air presents four (04) identical phases in pairs, reflecting the chimney’s operation throughout day. The temperature difference between the outlet and inlet of the chimney reaches a maximum of 17˚C with an average of 12.6˚C. Regarding airflow, the maximum air velocity at the chimney outlet is 0.8 m/s, and the average velocities have consistently been greater than or equal to 0.46 m/s. Thus, it can be concluded that the solar chimney is capable of providing ventilation for the preservation chamber through thermal draft.

关键词： Solar Chimney Natural Ventilation Thermal Draft Airflow Chimney Effect

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

Improvement of Mechanical Qualities of Clay Material through Coconut Fiber Stabilization

引用

Materials Sciences and Applications 2024年第7期15卷 201-212页

作者： boukaré ouedraogo Abdoulaye Compaore Moumouni Derra Kalifa Palm Dieudonné Joseph Bahiebo Laboratoire dEnergies Thermiques Renouvelables (LETRE) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratoire Chimie Analytique de Physique Spatiale et Energtique Universit Norbert ZONGO Koudougou Burkina Faso Institute de Recherche en Sciences Appliques et Technologies (IRSAT/CNRST) Ouagadougou Burkina Faso Laboratoire de Matriaux et Environnement (LAME) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso

The criticisms regularly formulated towards clay or soil, in general, are its weak mechanical qualities and low water quality. Therefore, it is necessary to find techniques to improve the properties of this material, which is widely used worldwide. Here, we propose stabilizing clay with coconut fiber as a solution to enhance its mechanical properties. To do this, we used an experimental method, first determining the geotechnical properties of the clay and then its mechanical properties. The geotechnical study using the Proctor Test revealed that the dry density of the clay is γb = 1.42 g/cm3, and its water content is W = 22.3%. By applying the rolling method, the Atterberg limits were determined: liquid limit Wl = 63.6, plastic limit Wp = 27.9, plasticity index Ip = 35.7, and consistency index Ic = 1.46. With 25 P = 35.7 1.3, according to the water classification, it falls into class A3ts. The mechanical part focused on compression and flexural strengths obtained using a PROETI hydraulic press. We obtained a flexural strength of 0.63 MPa for simple clay (BA);0.89 MPa for clay + 0.25% fiber (BAF1/4);1.68 MPa for clay + 0.5% fiber (BAF1/2);1.87 MPa for clay + 0.75% fiber (BAF3/4);and 3.91 MPa for clay + 1% fiber (BAF1). As for the compression strength, BA = 5.90 MPa, BAF1/4 = 6.395 MPa, BAF1/2 = 6.292 MPa, BAF3/4 = 6.065 MPa, and BAF1 = 5.423 MPa. The addition of fiber has thus improved the mechanical qualities of the simple clay. These stabilized bricks can be used for sustainable and bioclimatic construction, providing higher durability and good comfort.

关键词： Compression Strength Flexural Strength Coconut Fiber Clay Geotechnical Properties

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

Study Optimization of a Hybrid Solar-Wind System from an Individual in Ouagadougou

引用

Open Journal of Applied Sciences 2022年第11期12卷 1796-1808页

作者： Abdoulaye Compaore boukaré ouedraogo Kayaba Haro Rimnogdo Wilfried ouedraogo Yassia Belem Oumar Sanogo Institute of Research in Applied Sciences and Technologies (IRSAT/CNRST) Ouagadougou Burkina Faso Norbert ZONGO University Koudougou Burkina Faso University Joseph KI-ZERBO Ouagadougou Burkina Faso

This work is a contribution to the study of hybrid systems for converting solar and wind energy into electricity in Burkina Faso. The approach consists of evaluating and analyzing the production of a wind turbine and a solar field in order to optimize the production of all the technologies. The results obtained made it possible to evaluate the operating performance of the installation and to show the complementarity between the two energy sources with regard to temporary and seasonal variations in resources. During nighttime periods or periods of low sunlight, the wind turbine is a good alternative to energy storage by batteries, the output of the wind turbine can be up to 853.76 W. It was also a question of proposing solutions for optimizing the hybrid system through the automation of the hybrid charge regulator. A minimum height of 30 m above the ground has been chosen as the optimum height for the wind turbine.

关键词： Global Solar Flux Hybrid System Energy Conversion PV-Wind Turbine Automation

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

Polycrystalline Silicon Solar Cell p-n Junction Capacitance Behavior Modelling under an Integrated External Electrical Field Source in Solar Cell System

引用

Energy and Power Engineering 2020年第5期12卷 143-153页

作者： Adama ouedraogo boukaré ouedraogo Boureima Kaboré Dieudonné Joseph Bathiebo Laboratory of Thermal and Renewable Energies Department of Physics Unit of Training and Research in Pure and Applied Sciences Université Joseph KI-ZERBO Ouagadougou Burkina Faso Centre Universitaire Polytechnique de Kaya (CUP-Kaya) Kaya Burkina Faso Université Norbert ZONGO Koudougou Burkina Faso

The state of the p-n junction is very important to explain the performances of a solar cell. Some works give the influence of the electric field on the junction capacitance. However, these works do not relate the quality of the p-n junction under the electic field. The present manuscript is about a theoretical modelling of the p-n junction capacitance behavior of the polycrystalline silicon solar cell under an integration of the external electrical field source. An external electrical source is integrated in a solar cell system. The electronic carriers charge generated in the solar cell crossed mainly the junction with the great strength external electrical field. In open circuit, this crossing of the electronic charge carriers causes the thermal heating of the p-n junction by Joule effect. The p-n junction capacitance plotted versus the junction dynamic velocity and the photo-voltage for different external electrical fields. The electric field causes the decrease of the photo-voltage mainly the open-circuit photo-voltage. The decrease of the photo-voltage translates the narrowing of the Space Charge Region (SCR). The average value of the external electric field used in this study is not sufficient to cause the breakdown of the p-n junction of the solar cell system under integration of the external electrical field production source. The increase of the electrical field causes rather the narrowing of the SCR. That can provide an improvement of the solar cell’s electrical outputs.

关键词： Polycrystalline Silicon Solar Cell Space Charge Region Photo-Current Photo-Voltage Conversion Efficiency pn-Junction Capacitance External Electrical Field

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

Phytochemical Screening by High-Performance Thin-Layer Chromatography, Antioxidant Activities and Acute Toxicity of Trunk Barks Extracts of Lannea velutina A. Rich

引用

American Journal of Analytical Chemistry 2022年第10期13卷 365-381页

作者： boukaré Kaboré Moumouni Koala Mathieu Nitiema Windingoudi Rimwagna Christian ouedraogo Souleymane Compaoré Lazare Belemnaba Salfo ouedraogo Sylvain Ilboudo Noufou ouedraogo Constantin M. Dabiré Félix B. Kini Sylvin ouedraogo Eloi Palé Laboratoire de Chimie Organique et de Physique Appliquée (LCOPA) école Doctorale Sciences et Technologie UniversitéJoseph KI-ZERBO Ouagadougou Burkina Faso Département Médecine-Pharmacopée Traditionnelles/Pharmacie (MEPHATRA/Ph) Institut de Recherche en Sciences de la Santé (IRSS/CNRST) Ouagadougou Burkina Faso International ResearchLoboratory-Environnement Santé Sociétés (IRL 3189 ESS) CNRST/CNRS/UCAD/UGB/USTTB Burkina Faso Laboratoire de Chimie et énergies Renouvelables Université Nazi BONI Bobo Burkina Faso

Lannea velutina is a traditional herbal remedy used to treat various diseases, including hypertension (HBP). Herbal medicines are affordable, and some have minimal side effects;they are rich in bioactive components that encourage prevention and treatment. This work uses appropriate experimental paradigms to investigate the phytochemical composition, antioxidant activity, and acute oral toxicity of L. velutina trunk bark extracted in water, methanol, ethyl acetate, dichloromethane, and hexane. According to a high-performance thin-layer chromatography profile, this shrub’s bark contains sterols, saponosides, flavonoids, and tannins. Compared to ethyl acetate and aqueous extracts, the methanol extract had the highest total phenolic (607.06 ± 0.6 mg GAE/g DW), flavonoid (20.97 ± 0.23 mg QE/g DW), and condensed tannins (194.50 ± 0.75 CE/g DW) content. The methanol extract displayed the highest antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capability assay (IC50 = 8.59 g/mL;AAI = 4.66) compared to the other extracts. It exhibited antiradical action comparable to that of Trolox (IC50 = 15.16 g/mL), ascorbic acid (IC50 = 11.94 g/mL), and catechin (IC50 = 11.64 g/mL). The connection between flavonoid concentration and hydrophilic antioxidant activity was robust (r = 0.997). Mice were used to evaluate the acute oral toxicity of ethyl acetate, methanol, and aqueous extracts using guidelines 425 of the Organization for Economic Cooperation and Development. All tested extracts have an estimated LD50 greater than 2000 mg/kg body weight. The truncal bark of L. velutina could be an alternative source for HTA management.

关键词： Lannea velutina Phytochemicals Proanthocyanidins Antioxidants LD50

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

HPTLC Phytochemical Screening and Hydrophilic Antioxidant Activities of Apium graveolensL., Cleome gynandraL., and Hibiscus sabdariffaL. Used for Diabetes Management

引用

American Journal of Analytical Chemistry 2021年第1期12卷 15-28页

作者： Moumouni Koala Alphonsine Ramde-Tiendrebeogo Noufou ouedraogo Sylvain Ilboudo boukaré Kaboré Félix B. Kini Sylvin ouedraogo Institut de Recherche en Sciences de la Santé Centre National de la Recherche Scientifique et Technologique (IRSS/CNRST) Ouagadougou Burkina Faso Laboratoire de Chimie Organique et Physique Appliquées (L.C.O.P.A.) Université Joseph KI-ZERBO UFR/SEA Département de Chimie Ouagadougou Burkina Faso Unité Mixte Internationale Environnement-Santé-Société (UMI 3189 ESS) CNRST/CNRS/UCAD/UGB/USTTB-P&ocirc le Burkina Ouagadougou Burkina Faso

Diabetes mellitus is a socially significant disease characterized by chronic hyperglycemia and metabolic disorders of proteins, carbohydrates, and lipids due to reduced function of insulin. Medicinal plants, rich in bioactive components that promote prevention and treatment, are inexpensive and no side effects. Apium graveolens, Cleome gynandra, and Hibiscus sabdariffa from Burkina Faso were investigated for their phytochemical profile and antioxidant activities. The high-performance thin-layer chromatography profile revealed flavonoids, tannins, and sterols in these herbaceous. The Hibiscus sabdariffa methanolic extract exhibited the highest total phenolic (138.4 ± 0.5 mg GAE/g DW) and flavonoid (52.8 ± 0.6 mg RuE/g DW) contents comparatively to Cleome gynandra and Apium graveolens. Hibiscus sabdariffa methanolic extract also presented the highest antioxidant activity (IC50 = 0.31 ± 0.002 mg/mL) using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay. A high correlation between flavonoid contents and hydrophilic antioxidant activities (r = 0.99) was observed, indicating that flavonoids contribute significatively to these herbaceous antioxidant properties. Apium graveolens, Cleome gynandra, and Hibiscus sabdariffa constitute a natural source of phenolic compounds that could be exploited in diabetes mellitus management.

关键词： Diabetes Mellitus Medicinal Plants Flavonoids Contents Hydrophilic Antioxidant Activity HPTLC Screening

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

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

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：