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Clean Energy 2023年第4期7卷 808-823页

作者： mohammed a.qasim Vladimir I.Velkin Sergey E.Shcheklein Nuclear Power Plants and Renewable Energy Sources Department Ural Federal University620002 YekaterinburgRussia Department of Projects and Engineering Services Ministry of HealthBaghdad 10047Iraq

The concept of employing thermoelectric generators(TEGs)to recover energy from waste heat has gained popularity,with applications that range from milliwatt to kilowatt levels of output *** this study,a hybrid photovoltaic panel and thermoelectric generator(HPVTEG)system consisting of an integrated heat exchanger,a commercial polycrystalline silicon photovoltaic(PV)panel and a commercial bismuth telluride TEG was ***,TE components can be used to cool PV modules,increasing their output power via the Seebeck *** main finding is that the hybrid system has a reduced average temperature of 16.01°*** average power of the stand-alone PV panel is 28.06 W,but that of the HPVTEG system is 32.76 W,which is an increase of 4.7 *** conversion efficiency and power of the hybrid system increased by 16.7%and 16.4%,respectively,compared with a stand-alone PV *** HPVTEG system achieved an average exergy efficiency of 12.79%compared with 10.98%for a stand-alone PV *** to the calculation results,the levelized cost of energy(LCOE)of the stand-alone PV panel can range from 0.06741 to 0.10251 US$/kWh depending on how many days it is in operation,while the LCOE of the HPVTEG system can range from 0.06681 to 0.10160 US$/kWh.

关键词： PV TEG waste heat hybrid system heat exchanger

An efficient energy-management strategy for a DC microgrid powered by a photovoltaic/fuel cell/battery/supercapacitor

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Clean Energy 2022年第6期6卷 827-839页

作者： Furqan A.Abbas Adel A.Obed mohammed a.qasim Salam J.Yaqoob Seydali Ferahtia Department of Electrical Engineering Electrical Engineering Technical CollegeMiddle Technical UniversityBaghdad 10001Iraq Department of Nuclear Power Plants and Renewable Energy Sources Ural Federal University19 Mira St620002 YekaterinburgRussia Department of Projects and Engineering Services Ministry of HealthBaghdad 10001Iraq Department of Research and Education Authority of the Popular CrowdPrime MinisterBaghdad 10001Iraq Laboratore d’Analyse des Signaux et Systemes Department of Electrical EngineeringUniversity of M’silaMsila 28000Algeria

The outcome of this paper is to suggest an efficient energy-management strategy(EMS)for a direct-current(DC)microgrid(MG).The typical MG is composed of two renewable energy sources[photovoltaic(PV)systems and fuel cells(FCs)]and two energy-storage elements(lithium-ion battery and supercapacitor).An EMS was proposed to ensure optimal bus voltage with a power-sharing arrangement between the load and the *** a result,in the suggested DC MG,non-linear flatness control theory was used instead of the traditional proportional-integral control *** suggested EMS is intended to supply high power quality to the load under varying load conditions with fluctuating solar irradiation while considering the FC *** validate and prove the effectiveness of the proposed EMS,a MATLAB®environment was *** addition,the output power of the PV system was maximized using the particle swarm optimization algorithm as a maximum power point tracking(MPPT)technique to track the MPP of the 3000-W PV system under different irradiance *** results show that the suggested EMS delivers a stable and smooth DC bus voltage with minimum overshoot value(0.1%)and improved ripple content(0.1%).As a result,the performance of the DC MG was enhanced by employing the flatness control theory,which provides higher power quality by stabilizing the bus voltage.

关键词： photovoltaic fuel cell lithium energy management flatness control supercapacitor non-linear control

Study of total phenol,flavonoids contents and phytochemical screening of various leaves crude extracts of locally grown Thymus vulgaris

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Asian Pacific Journal of Tropical Biomedicine 2013年第9期3卷 705-710页

作者： Mohammad Amzad Hossain Khulood Ahmed Salim AL-Raqmi Zawan Hamood AL-Mijizy Afaf mohammed Weli qasim Al-Riyami School of Pharmacy College of Pharmacy and NursingUniversity of Nizwa

Objective:To prepare various crude extracts using different polarities of solvent and to quantitatively evaluate their total phenol,flavonoids contents and phytochemical screening of Thymus vulgaris collected from Al Jabal Al Akhdar,*** of ***:The leave sample was extracted with methanol and *** it was defatted with water and extracted with different polarities organic solvents with increasing *** prepare hexane,chloroform,ethyl acetate,hutanol and methanol crude extracts were used for their evaluation of total phenol,flavonoids contents and phytochemical screening *** established conventional metliods were used for quantitative determination of total phenol,flavonoids contents and phytochemical ***:Phytochemical screening for various crude extracts were tested and shown positive result for flavonoids,saponins and steroids *** result for total phenol content was the highest in hutanol and the lowest in methanol crude extract whereas the total flavonoids contents was the highest in methanol and the lowest hexane crude ***:The crude extracts from locally grown Thymus vulgaris showed high concentration of flavonoids and it could be used as antibiotics for different curable and uncurable diseases.

关键词： Thymus vulgaris L., Various crude extracts Phytochemical screening Soxhlet extractor Total phenol Flavonoids contents.

Gas chromatography-mass spectrometry analysis of different organic crude extracts from the local medicinal plant of Thymus vulgaris L

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Asian Pacific Journal of Tropical Biomedicine 2013年第1期3卷 69-73页

作者： Laila Salim Al Hashmi Mohammad Amzad Hossain Afaf mohammed Weli qasim Al-Riyami Jamal Nasser Al-Sabahi School of Pharmacy College of Pharmacy and NursingUniversity of NizwaP.0.Box 33Postal Code 616NizwaSultanate of Oman Central Instrument Laboratory College of Agriculture and Marine SciencesSultan Qaboos UniversitySultanate of Oman

Objective:To isolate and analyze the chemical composition in different crude extracts of from the leaves of locally grown of Thymus vulgaris L(***)by gas chromatography-mass spectrometry(GC-MS).Methods:The shade dried leaves powder was extracted with methanol by using Soxhlet *** crude extracts of *** and the derived fractions of hexane,chloroform,ethyl acetate and butanol were ***:Qualitative analyses of various organic crude extracts of *** by using GC-MS showed that there were different types of high and low molecular weight *** of the isolated and identified compounds by GC-MS in the crude extracts are basically biologically ***,the *** leaf possessed certain characteristics that can be ascribed to cultivation on a domestic *** crude extracts were prepared from the powder leaves of *** for respective compounds can be chosen on the basis of above GC-MS ***:All the major compounds were identified and characterized by spectroscopic method in different organic crude extracts of *** are biologically active *** the identification of a good number of compounds in various crude extracts of *** might have some ecological role.

关键词： Thymus vulgaris L Preparation crude extracts Soxhlet extractor GC-MS analyses

Chemical composition of essential oils and in vitro antioxidant activity of fresh and dry leaves crude extracts of medicinal plant of Lactuca Sativa *** to sultanate of Oman

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Asian Pacific Journal of Tropical Biomedicine 2013年第5期3卷 353-357页

作者： Rahma Said Salim Al Nomaani Mohammad Amzad Hossain Afaf mohammed Weli qasim Al-Riyami Jamal Nasser Al-Sabahi School of Pharmacy College of Pharmacy and NursingUniversity of Nizwa Central Instrument Laboratory College of Agriculture and Marine SciencesSultan Qaboos University

Objective:To isolate and analyse the chemical composition in the essential oils and free radical scavenging activity of different crude extracts from the fresh and dry leaves of vegetable plants of Lactuca sativa L.(***).Methods:The essential oils and volatile chemical constituents were isolated from the fresh and dry leaves of ***(lettuce)grown in Sultanate of Oman by hydro distillation *** antioxidant activity of the crude extracts was carried out by well established free radical scavenging activity(DPPH)***:About 20 chemical compounds of different concentration representing 83.07%and 79.88%respectively were isolated and identified by gas chromatography-mass spectroscopy in the essential oils isolated from the fresh and dry leaves asα-pinene(5.11%and 4.05%).γ-cymene(2.07%and 1.92%),thymol(11.55%and 10.73%),durenol(52.00%and 49.79%),α-terpinene(1.66%and 1.34%),thymol acetate(0.99%and 0.67%),caryophyllene(2.11%and 1.98%),spathulenol(3.09%and 2.98%).camphene(4.11%and3.65%),limonene(1.28%and 1.11%)representing these major chemical ***,some other minor chemical constituents were also isolated and identified from the essential oil of lettuce including p-pinene,α-terpinolene,linalool,4-terpineol,α-terpineol,o-methylthymol,L-alloaromadendrene and ***:The chemical consliluents in the essential oils from the locally grown lettuce were identified in the following classes or groups of chemical compounds such as monoterpenes,sesquiterpenes volatile organic compounds and their oxygenated ***,the essential oils and the crude extracts from Omani vegetable species of lettuce are active candidates which would be used as antioxidant,antifungal or antimicrobial agents in new drugs preparation for therapy of infectious diseases.

关键词： Lactuca saliva Omani lettuce Clevenger apparatus Essential oil Durenol Thymol Soxhlet extractor Organic crude extracts Antioxidant activity GC-MS analyses

Studies on free-radical scavenging activity and identification of active ingredients of different plant crude extracts of Mentha piperita collected from Sur,Sultanate of Oman

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Journal of Coastal Life Medicine 2014年第10期 805-810页

作者： Mohammad Amzad Hossain Aqeela Said Hamed AL Orimi Afaf mohammed Weli qasim Al-Riyami Jamal Nasser Al-Sabahi School of Pharmacy College of Pharmacy and NursingUniversity of NizwaP.O.Box 33Postal Code 616NizwaSultanate of Oman Central Instrument Laboratory College of Agricultural and Marine SciencesSultan Qaboos UniversitySultanate of Oman

Objective:To determine free radical scavenging activity and active chemical ingredients of different plant crude extracts of Mentha piperita(***).Methods:The dried powder leaves of *** were extracted with polar organic solvent by Soxhlet *** crude extract and its fractions of hexane,chloroform,ethyl acetate and butanol crude extracts were *** antioxidant activity of different crude extracts from *** was carried out by DPPH method with minor modification,and the active chemical ingredients of different plant crude extracts of *** were analyzed by gas chromatography-mass spectrometry(GC-MS).Results:Qualitative analysis of different polarities crude extracts by GC-MS found different types of active organic *** antioxidant activity of different crude extracts were found to be in the order of chloroform extract>butanol extract>ethyl acetate extract>hexane extract>methanol *** identified compounds in the plant crude extracts by GC-MS were biologically ***:Therefore,the isolation,purification,identification and characterization of bioactive compounds from various crude extracts of *** might have ecological significance.

关键词： Mentha piperita Lamiaceae Crude extracts Antioxidant activity DPPH Gas chromatography-mass spectrometry analysis

Vibration Analysis of Frame Structure with Soil-Structure Interaction

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Journal of Environmental Science and Engineering(B) 2015年第5期4卷 262-281页

作者： Raft mohammed qasim Department of Environment and Pollution Engineering College of Engineering Technical University of Southern Technical Basrah 00964 Iraq

A common design practice for dynamic loading assumes the frame fixed at their bases. In reality, the supporting soil medium allows movement to some extent due to its property to deform. This may decrease the overall stiffness of the structural system and may increase the natural period of the system. The effect of soil flexibility is suggested to be accounted through consideration of springs which have specified stiffness and soil half space. Results show that the dynamic response of frame structure to vibrations is due to applied dynamic load and is highly dependent on the soil type and the method of modeling soil structure interaction. The response of frame structure under dynamic load is higher in case of linear discrete independent spring as comparing with perfect bond cases. Except the response of frame in case of piles embedded in soft clay, half space are higher than frame with piles and linear elastic spring due to the interaction between the frequencies of applied load and frequencies of frame structure. Also, result showed that it is important to include the soil-structure interaction in the analysis of the system in order to correctly simulate the dynamic problem for controlling on the resonance phenomena.

关键词：结构相互作用框架结构振动分析土壤介质结构系统桩身结构设计实践动态加载

Bearing Capacity Map for An-Najaf and Kufa Cities Using GIS

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Engineering（科研） 2018年第5期10卷 262-269页

作者： Laheab A. Jasem Al-Maliki Sohaib Kareem Al-Mamoori Khaled El-Tawel Hussain M. Hussain Nadhir Al-Ansari mohammed Jawad Al Ali Department of Hydraulic Engineering Structures Faculty of Water Resources Engineering Green University of Al Qasim Baghdad Iraq Department of Environmental Planning Faculty of Physical Planning University of Kufa Najaf Iraq Lebanese University Faculty of Engineering Beirut Lebanon Remote Sensing Center University of Kufa Najaf Iraq Department of Civil Environmental and Natural Resources Engineering Lulea University of Technology Lulea Sweden Department of Environmental Planning Faculty of Physical Planning University of Kufa Najaf Iraq

An-Najaf province is situated in south-western part of Iraq. It is 70 meters above the sea level in the dry desert environment. The city is considered as one of the most important cities in Iraq, facing a fast population growth and continuous development in constructions such as residential complexes, hotels, bridges and shopping malls. Soil investigation data for An-Najaf Province (An-Najaf and Kufa cities) from 464 boreholes drilled by the Na-tional Centre for Construction Laboratories & Researches (NCCLR)/Babylon laboratory were used in this research. The data were analysed and possessed using Excel program then represented on the Geographical Information System (GIS) program by Inverse Distance Weighted (IDW) tool to create an allowable bearing capacity map for the soil at depths 0 - 2 meters. The allowable bearing capacity is one of the most important soil characteristics to be considered when making a database for An-Najaf city soil. Geographical Information System GIS program enables to create reliable database for any characteristic and it is one of the best programs to produce an accurate map and allow ease in dealing with it. Those maps cover all the studied areas and by using contour lines, approximate values for no-data areas can be obtained. The results show that the allowable bearing capacity range is 5 - 20 Ton/m2 for both An-Najaf and Kufa cities. Kufa city has the range 5 - 9 Ton/m2. An-Najaf city has the range 7 - 18 at the center, 8 - 10 Ton/m2 at the north eastern part, 7 - 14 Ton/m2 for the north western part, 6 - 12 Ton/m2 at the south eastern and 12 - 19 Ton/m2 at the south western.

关键词： Allowable Bearing Capacity Geographical Information System GIS AN-Najaf and Kufa Cities Geotechnical Maps Standard Penetration Test (SPT)