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A new technique for fault diagnosis in transformer insulating oil based on infrared spectroscopy measurements

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High Voltage 2024年第2期9卷 319-335页

作者： mohamed m.F.Darwish mohamed H.A.hassan Nagat m.K.Abdel-Gawad matti Lehtonen Diaa-Eldin A.mansour Department of Electrical Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland Department of Electrical Power Engineering Egypt-Japan University of Science and Technology(E-JUST)New Borg El-Arab CityEgypt Department of Electrical Power and machines Engineering Faculty of EngineeringTanta UniversityTantaEgypt

Condition monitoring of the insulating system within power transformers has a m.s.ive importance according to the electrical *** gas analysis(DGA)is frequently used for this ***,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of ***,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault ***,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to ***,the contribution of this research is to use infrared spectroscopy measurements as a new effective technique substituting the DGA method for fault diagnosis in insulating *** inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°Cmperaturest cells were crafted especially for serving the simulation processes inside the laboratory for both types of inception ***,six samples of pure paraffinic mineral oil were taken to be degraded in the *** that,all of them besides another sample that were not subjected to any kind of faults were taken to be examined by Fourier transform infrared(FTIR)spectroscopy to obtain an overview of the oil's behaviour in each fault *** that,the FTIR analysis was initially verified utilising the DGA ***,for further affirmation,the dielectric dissipation factor(DDF)for all samples was *** the final analysis,the verification tests provide experimental evidence about the outperformance of this new optical technique in detecting the transformer's inception faults in addition to proving its potential for being a superior alternative to the well-known traditional diagnostic techniques.

关键词： fault diagnosis spectroscopy

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

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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

Green retrofitting of heritage buildings based on(3Ts)framework:An applied case study

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Frontiers of Architectural Research 2024年第4期13卷 776-798页

作者： Alaa O.shehata Asmaa m.hassan merhan m.s.ahda Naglaa A.megahed Architectural Engineering and Urban Planning Department Faculty of EngineeringPort Said UniversityPort SaidEgypt

Diverse heritage architecture characterizes Port said in Egypt,reflecting European and Arab *** Canal heritage villas comprise 25%of the total listed heritage buildings in the ***,it is important to retrofit them,aligning with the sustainable Development Goals(sDGs).By reviewing the previous literature related to the green retrofitting of heritage buildings,the(3Ts)framework can be considered a holistic framework that covers the latest trends due to its three components:targets,tools,and tasks,which help the success of the process through a holistic vision of supporting building information modeling(BIm)technologies and organizing stakeholders’*** paper aims to apply the(3Ts)framework to suez Canal heritage villas in Port said,*** applied study is based on how stakeholders perceive their input and decision-making,measuring the climate parameters,proposing several green retrofits,and integrating them into green *** of scenarios is conducted by utilizing the Design Builder simulation ***,the skelion plugin calculates the photovoltaic system.s.PVs)energy *** results indicated that the total energy savings could reach approximately 12%e74%and nearly 10%e73%CO₂em.s.ions reduction without affecting heritage values.

关键词： Green retrofitting Heritage buildings BIm BEs suez Canal heritage villas Port said/Egypt

Novel sustainable Cellulose Acetate Based Biosensor for Glucose Detection

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Journal of Renewable materials 2024年第2期12卷 369-380页

作者： m.F.Elkady E.m.El-sayed mahmoud samy Omneya A.Koriem H.shokry hassan Chemical and Petrochemical Engineering Department Egypt-Japan University of Science and TechnologyNew Borg El-ArabAlexandriaEgypt Fabrication Technology Research Department Advanced Technology and New Materials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-ArabAlexandria21934Egypt Department of Public Works Engineering Faculty of EngineeringMansoura UniversityMansoura35516Egypt Environmental Engineering Department Egypt-Japan University of Science and TechnologyNew Borg El-ArabAlexandriaEgypt Electronic materials Research Department Advanced Technology and NewMaterials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-ArabAlexandria21934Egypt

In this study,green zinc oxide(ZnO)/polypyrrole(Ppy)/cellulose acetate(CA)film has been synthesized via solvent *** film was used as supporting material for glucose oxidase(GOx)to sensitize a glucose *** nanoparticles have been prepared via the green route using olive leaves extract as a ***/Ppy nanocomposite has been synthesized by a simple in-situ chemical oxidative polymerization of pyrrole(Py)monomer using ferric chloride(FeCl3)as an oxidizing *** produced materials and the composite films were characterized using X-ray diffraction analysis(XRD),scanning electron microscope(sEm),Fourier transform infrared(FTIR)and thermogravimetric analysis(TGA).Glucose oxidase was successfully immobilized on the surface of the prepared film and then ZnO/Ppy/CA/GOx composite was sputtered with platinum electrode for the current determination at different initial concentrations of *** measurements proved the suitability and the high sensitivity of the constructed biosensor for the detection of glucose levels in different *** performance of the prepared biosensor has been assessed by measuring and comparing glucose concentrations up to 800 *** results affirmed the reliability of the developed biosensor towards real samples which suggests the wide-scale application of the proposed biosensor.

关键词： Biosensors composite films glucose polypyrrole green ZnO cellulose acetate

Facile synthesis of graphene anchored rare earth doped mixed metal ferrite nanorods:A potential candidate for azo dye mineralization

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Journal of Rare Earths 2024年第5期42卷 907-916,I0004页

作者： Tehmina Kousar muhammad Aadil sonia Zulfiqar sobhy mIbrahim.s.dra mubeen Warda hassan Kashuf shafiq Farzana mahmood Institute of Chemical sciences Bahauddin Zakariya UniversityMultan60800Pakistan Department of Chem.s.ry Rahim Yar Khan CampusThe Islarnia University of BahawalpurRahim Yar Khan64200Pakistan Department of Chem.s.ry Faculty of ScienceUniversity of Ostrava30.Dubna 22Ostrava70103Czech Republic Department of Chemical and Biological Engineering Iowa State UniversitySweeney Hall618 Bissell RoadAmeslowa50011United States Department of Biochem.s.ry College of ScienceKing Saud UniversityPO.Box 2455Riyadh11451Saudi Arabi Department of Chem.s.ry The Women University Multan66000Pakistan

Bandgap tuning using rare earth metals as dopants in ferrite-based photocatalytic materials has received a lot of interest because the Fermi 4f energy of these metals generates a sub-energy state in the bandgap generated by the overlapping of Fe-3d and O-2p ***,dysprosium-doped cobalt-nickel mixed ferrite(D-CNFO)and its graphene-reinforced composite(D-CNFO@G)were prepared and an ideal photocatalyst material for azo dye mineralization was proposed.A cost-effective combination of wetchemical and ultrasonication methods was used to prepare the doped and composite *** characterization methodologies were used to scrutinize the optical,compositional,structural,morphological,and photocatalytic characteristics of as-prepared *** X-ray diffraction analysis identified the spinel phase's(cubic)structure,while the electronic spectroscopy examination confirmed the prepared samples'rod-like *** UV/visible absorbance spectrum.s.ows the higher light harvesting behavior of the D-CNFO@G in the visible *** mineralization performance of the DCNFO and D-CNFO@G composites was analyzed using Congo-red(an anionic dye),a well-known azo *** D-CNFO@G sample removes Congo-red dye at a rate alm.s. 2.4%faster than the D-CNFO *** experiment involving trapping free radicals indicates that hydroxyl radical play s a crucial role in dye *** the D-CNFO@G catalyst is magnetic and can be isolated easily from the photocatalytic system,it shows an awkward cycle activity of more than 96%after five mineralization *** asprepared D-CNFO@G composite is proved as an excellent option for azo dye mineralization because of the combined impacts of rare earth doping,graphene reinforcement and nanotechnology.

关键词： azo-dye Composite Graphene Dy-doped Nanotechnology Rare earths

FlowBreakdown of Hybrid Nanofluid on a Rigid surface with Power Law Fluid as Lubricated Layers

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Computer modeling in Engineering & sciences 2024年第2期138卷 1485-1499页

作者： mirza Naveed Jahangeer Baig Nadeemsalamat sohail Nadeem NaeemUllah mohamed Bechir Ben Hamida hassan Ali Ghazwani sayed m.Eldin A.s.Al-shafay Instituite of mathematics Khwaja Fareed University of Engineering and Information TechnologyRahim yar Khan64200Pakistan Department of mathematics Quaid-I-Azam UniversityIslamabad44000Pakistan Department of mathematics Wenzhou UniversityWenzhou325035China College of Engineering Department of Mechanical EngineeringImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11564Saudi Arabia Research Laboratory of Ionized Backgrounds and Reagents studies(EmIR) Preparatory Institute for Engineering Studies of Monastir(IPEIM)University of MonastirMonastir5060Tunisia Higher school of sciences and Technology of Hammam.s.usse Department of PhysicsJazan82511Kingdom of Saudia Arabia Department of mechanical Engineering Faculty of engineeringJazan UniversityP.O.Box 45124JazanKingdom of Saudia Arabia Center of Research Faculty of EngineeringFuture University in EgyptNew Cairo11835Egypt Department of mechanical Engineering College of EngineeringPrince Sattam bin Abdulaziz UniversityAlkharj16436Saudi Arabia

Thiswork investigates an oblique stagnation point flowof hybrid nanofluid over a rigid surface with power lawfluidas lubricated layers. Copper (Cu) and silver (Ag) solid particles are used as hybrid particles acting in water H2O asa base fluid. The mathematical formulation of flow configuration is presented in terms of differential systemthat isnonlinear in nature. The thermal aspects of the flow field are also investigated by assuming the surface is a heatedsurface with a constant temperature T. Numerical solutions to the governing mathematical model are calculatedby the RK45 algorithm. The results based on the numerical solution against various flow and thermal controllingparameters are presented in terms of line graphs. The specific results depict that the heat flux increases over thelubricated-indexed parameter.

关键词： Oblique stagnation point flow hybrid nanofluid lubricated layer magnetohydrodynamics

Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： s.m.Yakout A.m.Youssef Inorganic Chem.s.ry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount *** the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on sEm images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher ch

关键词： semiconductor TiO_(2) Rare earths Congo red methylene blue solar spectrum Photodegradation

^(4)He monolayer on graphene:a quantum monte Carlo study

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Communications in Theoretical Physics 2024年第9期76卷 149-157页

作者： s Yu m Boninsegni Department of Physics University of AlbertaEdmontonAlbertaT6G 2H5Canada

We revisit the problem of adsorption of a single^(4)He layer on graphene,focusing on the commensurate(C_(1/3))crystalline phase,specifically on whether it may possess a nonzero superfluid response,and on the existence of superfluid phases,either(metastable)liquid or vacancy-doped *** make use of canonical quantum monte Carlo simulations at zero and finite temperature,based on a realistic microscopic model of the *** results confirm the absence of any superfluid response in the commensurate crystal,and that no thermodynamically stable uniform phase exists at lower *** evidence of a possibly long-lived,metastable superfluid phase at C_(1/3)coverage is ***,the results of ground-state projection methods and finite-temperature simulations are entirely consistent.

关键词： superfluidity low-dimensional systems quantum monte Carlo helium supersolids

Direct microwave leaching conditions of rare earth elements in fluorescent wastes

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Journal of Rare Earths 2024年第6期42卷 1165-1174,I0007页

作者： A.Bilen B.Birol m.N.saridede s.s.Kaplan m.s.sonmez Department of metallurgical and materials Engineering Yildiz Technical UniversityIstanbulTurkey Department of Chemical Engineering and materials science Stevens Institute of TechnologyNew JereyUSA Department of metallurgical and materials Engineering Istanbul Technical UniversityIstanbulTurkey

The luminescent phosphor powder in the fluorescent lamp constitutes 2%of the lamp’s *** can be mentioned that fluorescent wastes are a crucial raw material to produce rare earth *** the present study,microwave leaching process was conducted to dissolve rare earth elements yttrium(Y),europium(Eu),and remaining rare earth elements(REEs)present in the phosphor powder of the fluorescent *** the yields were *** the microwave leaching process,the effects of the temperature(80-160℃),acid type(hydrochloric acid(HCl),nitric acid(HNO_(3)),sulphuric acid(H_(2)sO_(4))),acid concentration(0.5-6 mol/L),solid to liquid ratio(0.1:10-0.5:10)and reaction time(5-90 min)parameters on leaching efficiencies of varying rare earth elements and calcium were *** highest yield was obtained in the direct microwave leaching of fluorescent waste with the experimental conditions of 6 mol/L HCl,160℃,0.1:10 solid-to-liquid ratio(s:L),and 90 *** energy calculations were made,and kinetic models of the reactions were obtained,and it is observed that Y and Eu dissolution is diffusion-controlled,on the other hand,lanthanum(La),cerium(Ce),and terbium(Tb)were examined to be chemical reaction ***,calcium(Ca)and gadolinium(Gd)seem coherent with the mixed ***,mathematical models of all experimental studies are created with the response surface Box-Behnken method and the correlation coefficients of all the models are over 90%.

关键词： Rare earth elements(REEs) Direct microwave leaching Fluorescent waste Kinetic models Response surface method