检索结果-南通市图书馆

Journal of modern Power systems and Clean Energy 2022年第2期10卷 450-458页

作者： Ahmed s.A.awad Dave Turcotte Tarek H.m.el-Fouly Natural Resources Canada Can-metENERGYVarennesCanadaon leave from the Electrical Power and Machines DepartmentFaculty of EngineeringAin Shams UniversityCairo 11566Egyp Natural Resources Canada CanmetENERGYVarennesCanada Advanced Power and Energy Center Khalifa UniversityAbu DhabiUnited Arab Emirates

The integration of renewable distributed generation(RDG)into distribution networks is promising and increasing ***,high penetration levels of distributed generation(DG)are often limited as they may have an adverse effect on the operation of distribution *** of the operation challenges is the interaction between DG and voltage-control equipment,e.g.,an under-load tap changer(ULTC),which is basically designed to compensate for voltage changes caused by slow load *** integration of variable DGs leads to rapid voltage fluctuations,which can negatively affect the tap operation of *** paper investigates the impact of high penetration levels of RDG on the tap operation of ULTC in distribution networks through *** mitigation techniques that can alleviate this impact are also *** these techniques,constant power-factor mode is regarded as the best trade-off between the simplicity and effectiveness of minimizing the number of tap *** are performed on a Canadian benchmark rural distribution feeder using OpenDss software.

关键词： Renewable energy distributed generation(DG) voltage regulator load tap changer distribution network.

Phosphoric Acid Pretreatment and saccharification of Paper sludge as a Renewable material for Cellulosic Fibers

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

Journal of Renewable materials 2024年第9期12卷 1573-1591页

作者： samar el-mekkawi Wafaa Abou-elseoud shaimaa Fadel Enas Hassan mohammad Hassan Chemical Engineering and Pilot Plant Department National Research CentreDokkiGiza12622Egypt Cellulose and Paper Department National Research CentreDokkiGiza12622Egypt

Recycling of paper sludge waste is crucial for establishing a sustainable green *** waste contains valuable sugars that can be converted into important chemicals such as ethanol,poly hydroxybutyrate,and lactic ***,the main challenge in obtaining sugars in high yield from paper sludge is the high crystallinity of cellulose,which hinders *** address this,pretreatment using phosphoric acid was optimized using response surface methodology to facilitate cellulose hydrolysis with minimal energy and *** created prediction model using the response surface method considered factors such as acid concentration(ranging from 60%to 85%),consistency(ranging from 4%to 10%),temperature(ranging from 25℃to 80℃),and time(ranging from 0.5 to 4 h).The results revealed that the model’s significant factors affecting the yield were acid concentration,reaction time,temperature,and the product of acid concentration and temperature,while the model’s significant factors affecting the crystallinity were the consistency,the temperature,and their *** results showed that the optimum conditions for pretreatment were using an acid concentration of 64%,temperature of 25℃,consistency of 10%,and time of 30 *** hydrolysis of the conditionally pretreated paper sludge resulted in a weight loss of 42%,compared to only 18%weight loss in non-pretreated paper ***,the optimized conditions led to low levels of furfurals and acetic acid,which are undesirable by-products that can interfere with sugar *** total sugar obtained under the optimized conditions was 0.43 g glucose/g sample(10.46 g/L),while the contents of methyl furfural,furfural,and acetic acid were 21.65,235.7,and 4.57 mg/L,*** study demonstrates the potential of phosphoric acid for pretreatment and hydrolysis of paper sludge,enabling efficient saccharification and the production of sugars with minimal undesired by-products.

关键词： Waste valorization fermentable sugars response surface methodology acid hydrolysis cellulose crystallinity

Efficiency of Bio-Fertilizing as One of the Natural Alternatives to Improve the Growth of Khaya senegalensis and swietenia mahagoni Trees and for sustainability

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Agricultural sciences 2024年第2期15卷 292-310页

作者： safaa A. s. Ghorab Nashwa H. mohamed Nader A. el-shanhorey Nabal s. el-shahat Amr R. Rabie Forestry and Timber Trees Department Horticulture Research Institute Agricultural Research Center Ismailia Egypt Forestry and Timber Trees Department Horticulture Research Institute Agricultural Research Center Alexandria Egypt Botanical Gardens Department Horticulture Research Institute Agricultural Research Center Alexandria Egypt Forestry and Timber Trees Department Horticulture Research Institute Agricultural Research Center Giza Egypt

A field experiment was carried out at Ismailia Research station, Ismailia Governorate from 2020-2022 to improve the growth of Khaya senegalensis and swietenia mahagoni by using a combination of mineral fertilizer (NPK) and biological fertilizer (Azotobacter chroococcum, Bacillus megatherium, and Bacillus circulant) as recommended dose under new sandy soils conditions. split plot designed with four treatments (Control, (50% mineral fertilizer (m.) + 50% Biological fertilizer (Bio.)), 100% m. and 100% Bio.) of each species. Vegetative growth, leaf area, tree biomass, stored carbon, basal area, tree volume, and in the soil both of microbial account and mineral content were determined. The experimental results showed no significant differences between studied species among the most studied parameters except for Khaya senegalensis which gave the highest significant difference in root biomass and below-stored carbon than swietenia mahagoni. Evidently, the highest significant growth parameters were 100% mineral fertilizer followed by (50% m. + 50% Bio.) as compared with control. No significant difference between 100% m. and (50% m. + 50% Bio.) of shoot dry biomass (15.19 and 12.02 kg, respectively) and above-stored carbon (0.28 and 0.22 mt, respectively). microbial account and mineral content in soil were improved after cultivation of tree species compared to before planting and control, especially with 50% mineral fertilizer and 50% bio-fertilizer treatment. In conclusion, a treatment containing 50% mineral fertilizer and 50% bio-fertilizer has led to the ideal Khaya senegalensis and swietenia mahagoni growth in sandy soil for cheaper and sustainable.

关键词： Khaya senegalensis swietenia mahagoni mineral Fertilizer Bio-Fertilizer Growth Parameters Tree Biomass stored Carbon sustainable

Thermodynamic Performance Analysis of Geothermal Power Plant Based on Organic Rankine Cycle (ORC) Using mixture of Pure Working Fluids

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy Engineering 2024年第8期121卷 2023-2038页

作者： Abdul sattar Laghari mohammad Waqas Chandio Laveet Kumar mamdouh el Haj Assad Department of mechanical Engineering Mehran University of Engineering and TechnologyJamshoro76062Pakistan Department of mechanical and Industrial Engineering College of EngineeringQatar UniversityDoha00000Qatar sustainable&Renewable Energy Engineering Department University of SharjahSharjah00000United Arab Emirates

The selection of working fluid significantly impacts the geothermal ORC’s *** a mixture as a working fluid is a strategy to improve the output of geothermal *** the current study,modelling and thermodynamic analysis of ORC,using geothermal as a heat source,is carried out at fixed operating *** model is simulated in the Engineering Equation solver(EEs).An environment-friendly mixture of fluids,i.e.,R245fa/R600a,with a suitable mole fraction,is used as the operating *** mixture provided the most convenient results compared to the pure working fluid under fixed operating *** impact of varying the evaporator pressure on the performance parameters,including energy efficiency,exergy efficiency and net power output is *** system provided the optimal performance once the evaporator pressure reached the maximum *** efficiencies:Energy and Exergy,and Net Power output of the system are 16.62%,64.08%and 2199 kW for the basic cycle and 20.72%,67.76%and 2326 kW respectively for the regenerative cycle.

关键词： Organic rankine cycle internal heat exchanger moderate-temperature geothermal source mixture of the fluid exergy

modelling the monthly hydrological balance using soil and Water Assessment Tool(sWAT)model:A case study of the Wadi mina upstream watershed

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Groundwater science and Engineering 2024年第2期12卷 161-177页

作者： Hanane mebarki Noureddine maref mohammed el-Amine Dris Civil Engineering and Environmental Laboratory(LGCE) University of Djillali LiabèsFaculty of TechnologyHydraulics departmentBen M'Hidi districtP.O.Box 8922000Sidi Bel AbbèsAlgeria.

modelling the hydrological balance in semi-arid zones is essential for effective water resource management,encompassing both surface water and *** study aims to model the monthly hydrological water cycle in the Wadi mina upstream watershed(northwest Algeria)by applying the soil and Water Assessment Tool(sWAT)hydrological *** modelling integrates spatial data such as the Digital elevation model(DEm),land use,soil types and various meteorological parameters including precipitation,maximum and minimum temperatures,relative humidity,solar radiation and wind *** sWAT model was calibrated and validated using data from January 2012 to December 2014,with a calibra-tion period from January 2012 to August 2013 and a validation period from september 2013 to December *** and parameter calibration were conducted using the sWAT-sA program,and model performance evaluation relied on comparing the observed discharge at the outlet of the basin with model-simulated discharge,assessed through statistical coefficients including Nash-sutcliffe Efficiency(NsE),coefficient of determination(R2)and Percent Bias(PBAIs).Calibration results indicated favourable objec-tive function values(NsE=0.79,R2=0.93,PBAIs=-8.53%),although a slight decrease was observed during validation(NsE=0.69,R2=0.86,and PBAIs=-11.41%).The application of the sWAT model to the Wadi mina upstream watershed highlighted its utility in simulating the spatial distribution of different components of the hydrological balance in this *** sWAT model revealed that approximately 71%of the precipitation in the basin evaporates,while only 29%contributes to surface runoff or infiltration into the soil.

关键词： sWAT model Performance Parameters Runoff Groundwater Wadi

Regulating microstructure and composition by carbonizing in-situ grown metal-organic frameworks on cotton fabrics for boosting electromagnetic wave absorption

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第8期17卷 7290-7300页

作者： Jie Jin Hongsen Long Hu Liu Yan Guo Tiantian Bai Ben Bin Xu mohammed A.Amin Hua Qiu mohamed H.Helal Chuntai Liu Changyu shen Zeinhom m.el-Bahy Zhanhu Guo state Key Laboratory of structural Analysis Optimization and CAE Software for Industrial EquipmentNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou 450002China China state Key Laboratory of Powder metallurgy Central South UniversityChangsha 410000China school of electronic Engineering North China University of Water Resources and Electric PowerZhengzhou 450046China Complex Conditions of High-end Tire Technology Innovation Center Shuguang Rubber Industry Research&Design Institute Co.LtdGuilin 541004China Integrated Composites Lab Department of Mechanical and Civil EngineeringNorthumbria UniversityNewcastle Upon TyneNE18STUK Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia shaanxi Key Laboratory of macromolecular science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Chemistry Faculty of Arts and ScienceNorthern Border UniversityRafha 73213Saudi Arabia Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt

High-temperature carbonized metal-organic frameworks(moFs)derivatives have demonstrated their superiority for promising electromagnetic wave(EmW)absorbers,but they still suffer from limited EmW absorption capacity and narrow *** the advantage of microstructure and chemical composition regulation for the design of EmW absorber,hierarchical heterostructured mos_(2)/Cos_(2)-Co_(3)O_(4)@cabonized cotton fabric(CF)(mCC@CCF)is prepared by growing ZIF-67 moFs onto CF surface,chemical etching,and *** from the dual loss mechanism of magnetic-dielectric multicomponent carbonized moFs,chemical etching and carbonization process can effectively introduce abundant micro-gap structure that can result in better impedance matching and stronger absorption capacity via internal reflection,doped heteroatoms(mo,N,s)to supply additional dipolar polarization loss,and numerous heterointerfaces among mos_(2),Cos_(2),Co_(3)O_(4),and CCF that produce promoted conduction loss and interfacial polarization ***,a minimal reflection loss of−52.87 dB and a broadest effective absorption bandwidth of 6.88 GHz were achieved via tunning the sample thickness and filler loading,showing excellent EmW absorption *** research is of great value for guiding the research on moFs derivatives based EmW absorbing materials.

关键词： metal-organic frameworks hierarchical structure chemical etching sulfurization electromagnetic wave absorption

Toward understanding the microstructure characteristics,phase selection and magnetic properties of laser additive manufactured Nd-Fe-B permanent magnets

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Extreme manufacturing 2024年第1期6卷 277-294页

作者： Bo Yao Nan Kang Xiangyu Li Dou Li mohamed el mansori Jing Chen Haiou Yang Hua Tan Xin Lin state Key Laboratory of solidiffcation Processing Northwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Arts et metiers Institute of Technology MSMPHESAM UniversitéF-51006 Chˆalons-en-ChampagneFrance Key Laboratory of metal High Performance Additive manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Texas A&m Engineering Experiment station Institute for Manufacturing SystemsCollege StationTX 77843United States of America

Nd-Fe-B permanent magnets play a crucial role in energy conversion and electronic *** essential magnetic properties of Nd-Fe-B magnets,particularly coercivity and remanent magnetization,are significantly infuenced by the phase characteristics and *** this work,Nd-Fe-B magnets were manufactured using vacuum induction melting(VIm),laser directed energy deposition(LDED)and laser powder bed fusion(LPBF)*** evolution and phase selection of Nd-Fe-B magnets were then clarified in *** results indicated that the solidification velocity(V)and cooling rate(R)are key factors in the phase *** terms of the VIm-casting Nd-Fe-B magnet,a large volume fraction of theα-Fe soft magnetic phase(39.7 vol.%)and Nd2Fe17Bxmetastable phase(34.7 vol.%)areformed due to the low R(2.3×10-1?C s-1),whereas only a minor fraction of the Nd2Fe14B hard magnetic phase(5.15 vol.%)is *** the LDED-processed Nd-Fe-B deposit,although the Nd2Fe14B hard magnetic phase also had a low value(3.4 vol.%)as the values of V(m s-1)and R(5.06×103?C s-1)increased,part of theα-Fe soft magnetic phase(31.7vol.%)is suppressed,and a higher volume of Nd2Fe17Bxmetastable phases(47.5 vol.%)*** a result,both the VIm-casting and LDED-processed Nd-Fe-B deposits exhibited poor magnetic *** contrast,employing the high values of V(>10-2m s-1)and R(1.45×106?C s-1)in the LPBF process resulted in the substantial formation of the Nd2Fe14B hard magnetic phase(55.8 vol.%)directly from the liquid,while theα-Fe soft magnetic phase and Nd2Fe17Bxmetastable phase precipitation are suppressed in the LPBF-processed Nd-Fe-B ***,crystallographic texture analysis reveals that the LPBF-processedNd-Fe-B magnets exhibit isotropic magnetic ***,the LPBF-processed Nd-Fe-B deposit,exhibiting a coercivity of 656 k A m-1,remanence of 0.79 T and maximum energy product of 71.5 k J m-3,achieved an acceptable magnetic perfor

关键词： laser additive manufacturing(LAm) Nd-Fe-B permanent magnets numerical simulation microstructure magnetic properties

electrochemical anodization of cast titanium alloys in oxalic acid for biomedical applications

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

Frontiers of Chemical science and Engineering 2024年第1期18卷 13-24页

作者： Engie m.safwat soha A.Abdel-Gawad madiha A.shoeib shimaa el-Hadad Restorative and Dental materials Department National Research CentreGiza 12622Egypt Chemistry Department Faculty of ScienceCairo UniversityGiza 12613Egypt Central metallurgical Research and Development Institute Helwan 11421Egypt

Titanium and its alloys have numerous biomedical applications thanks to the composition and morphology of their oxide *** this study,the colorful oxide films were formed by anodizing cast Ti-6Al-4V and Ti-6Al-7Nb alloys in a 10%oxalic acid solution for 30 s at different voltages(20–80 V)of a direct current power *** force microscopy was used as an accurate tool to measure the surface roughness of thin films on the nanometer *** electron microscopy and X-ray diffraction were performed to analyze surface morphology and phase *** to the results,the produced titanium oxide layer showed high surface roughness,which increased with increasing anodizing *** impact of anodizing voltages on the color and roughness of anodized layers was *** corrosion resistance of the anodized samples was studied in simulated body fluid at pH 7.4 and a temperature of 37℃ utilizing electrochemical impedance spectroscopy and the potentiodynamic polarization *** anodized samples for both alloys at 40 V were at the optimal voltage,leading to a TiO_(2) layer formation with the best compromise between oxide thickness and corrosion ***,findings showed that TiO_(2) films produced on Ti-6Al-7Nb alloys had superior surface roughness properties compared to those of Ti-6Al-4V alloys,making them more appropriate for orthopedic *** the obtained data and the fruitful discussion,it was found that the utilized procedure is simple,low-cost,and ***,anodization in 10%oxalic acid proved a viable alternative for the surface finishing of titanium alloys for biomedical applications.

关键词： DC anodization Ti-6Al-4V alloy Ti-6Al-7Nballoy oxidefilm corrosion

Planning Target Volume margin in Linac-Based stereotactic Radiosurgery for Brain metastases

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Cancer Therapy 2024年第7期15卷 265-272页

作者： Hany s. Attallah Radwa m. Hamed Khaled m. el-shahat Aliaa mahmoud mahmoud Abdallah Ibraheem Haggag Emad moustafa Adel Yassin Department of Radiation Oncology International Medical Center (IMC) Cairo Egypt Department of Radiation Oncology Armed Forces Medical Collogue (AFCM) Cairo Egypt Department of medical Physics Al Azhar University Cairo Egypt Department of medical Physics International Medical Center (IMC) Cairo Egypt Department of medical Physics Department of Clinical Oncology Faculty of Medicine Zagazig University Zagazig Egypt

Background: The treatment of brain metastases with radiotherapy has shifted to the use of stereotactic Radio-surgery (sRs). The technical issue of expanding the treatment volume around the Gross Tumor Volume (GTV) is a current debate. Radiotherapy centers use variable GTV-PTV margins, ranging from one to 2 mm. material and methods: We performed a dosimetric comparison in plans of twenty patients using three margins: PTV zero, PTV1, and PTV2. We also developed imaginary Peel volumes. These volumes are described as follows: Peel1 = PTV1 − GTV, Peel2 = PTV2 − GTV. Results: Our results showed that the mean PTV volume differed significantly across the different margins (p = 0.000). The V12 of the brain significantly varied as a function of PTV margin (p = 0.000). The target coverage and plan quality indices were not significantly different. The Peel volume dosimetric analysis showed that the mean dose was significantly higher in the nearby normal brain tissue: Peel1 (p = 0.022) and Peel 2 (p = 0.013). Conclusion: According to our dosimetric analysis, expanding the GTV into a PTV by 1 mm margin is more convenient than 2 mm.

关键词： sRs Brain metastases PTV

Exploring internship nursing students’ perception of gerontological nursing competencies: A descriptive study at Cairo University Hospitals

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Nursing 2023年第4期5卷 235-242页

作者： Naglaa el-s.yed elDARDERY ebtes.m mo’awad el-s.yed ebied Yousef moHAmmED Kholoud KHODARY Basmala moHAmmED sara moHAmmED Kholoud moHAmmED Ahmed KAmAL mostafa sHABAN Department of Geriatric Nursing Faculty of NursingCairo UniversityGizaEgypt

Objective:This research study explores the perceptions of gerontological nursing competencies,attitudes toward older individuals,and the willingness to provide care for the elderly among internship nursing *** and methods:A convenience sample of 350 internship nursing students from Cairo University Faculty of Nursing participated in the *** were collected using a set of comprehensive tools,including personal data and work experience assessment,the Hartford geriatric nurse competency tool,Kogan’s attitudes toward old people scale,and the modified elderly patient care ***:Descriptive analysis revealed balanced gender representation,with 60%identifying as *** percent of participants reported prior experience in gerontological ***-assessed competency scores indicated moderate proficiency in communication,physiological changes,and functional status *** such as pain management and restraint use demonstrated potential gaps in self-perceived *** toward older individuals were predominantly positive,and the willingness to provide care showed positive tendencies,with a minor degree of hesitation ***:The findings underscore the need for targeted interventions in nursing education to address competency gaps,enhance positive attitudes,and alleviate potential hesitations in caregiving for older *** the elderly population continues to grow,nursing education programs must prepare future practitioners to deliver comprehensive and compassionate care tailored to the unique needs of older adults.

关键词： Attitudes competencies elderly care gerontological nursing internship nursing students willingness