检索结果-南通市图书馆

Acta Geologica Sinica(english edition) 2021年第5期95卷 1568-1582页

作者： Mohamed A.ALI ahmed e.abdel gawad Mohamed M.GHONeIM Nuclear Materials Authority 530 El-MaadiCairoEgypt

The garnet muscovite granitic pegmatite of Um Solimate,in southern egypt,represents a promising asset for strategic and economic metals,especially Bi-Ni-Ag-Nb-Ta as well as U and *** ore bodies occur as large masses,pockets and/or veins of very coarse-grained pegmatites,which consist mainly of K-feldspar,quartz and albite with subordinate muscovite,garnet,and *** data revealed that e U-and e Th-contents of the pegmatites reach up to 39 ppm and 82 ppm,*** studied pegmatites are enriched in primary U and Th minerals(uraninite,coffinite,thorianite and uranothorite)as well as Hf-rich zircon and monazite,which give rise to anomalous radioactive ***-tantalium-bearing minerals(***,microlite and uranopyrochlore),xenotime,barite,galena,fluorite,and apatite are ubiquitous,and,consequently,the studied pegmatites belong tothe Niobium-Yttrium-Fluorine-type(NYF)*** noble metal mineralization includes argentite(Ag_(2)S),native Ni and Bi as well as bismite and *** addition,beryl and tourmaline are observed in pegmatites near the contact with metasediments and ultramafic *** observed compositional variations of Ta/(Ta+Nb)and Mn/(Mn+Fe)ratios in columbite(0.08-0.45 and 0.11-0.57,respectively)and Hf contents in zircon(3.54-6.46 wt%)may reflectan extreme degree of magmatic fractionation leading to formation of the pegmatite orebody.

关键词： radioactivity rare-metal mineralization pegmatites U/Th-bearing minerals Um Solimate egypt

Long-term outcomes of urethral balloon dilation for anterior urethral stricture: A prospective cohort study

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

Asian Journal of Urology 2024年第3期11卷 480-485页

作者： ahmed M.abdel gawad Abhijit Patil Abhishek Singh Arvind P.Ganpule Ravindra B.Sabnis Mahesh R.Desai Department of Urology Muljibhai Patel Urological HospitalNadiadIndia Department of Urology Faculty of MedicineAl-Azhar UniversityDamiettaEgypt

Objective:To prospectively follow up a cohort of anterior urethral stricture disease patients managed with balloon dilation(BD)for 3 years to evaluate the long-term outcomes and to study factors that contribute to ***:This study included men who had urethral BD for significant anterior urethral stricture disease between January 2017 and March *** about the patient age,stricture characteristics,and recurrence date were recorded,along with information on postoperative indwelling catheter use and operative ***,information about the self-calibration procedure was collected and where available,free flow(FF)measurements during the follow-up period were recorded and *** was defined as a lack of symptoms and acceptable FF rates(maximum flow rate>12 mL/s).Results:The final analysis was conducted on 187 *** mean follow-up period was 37 *** long-term overall success rate at the end of our study was 66.8%.Our recurrence rate was 7.4%at 12 months,24.7%at 24 months,and reached 33.2%at the end of our *** time to recurrence ranged from 91 days to 1635 days,with a mean of 670 *** stricture-free survival was significantly shorter with lengthy peno-bulbar(p=0.031)and multiple strictures(p=0.015),and in the group of patients who were not committed to self-calibration protocol(pever,post-procedural self-calibration was the most important factor that may have decreased the incidence of recurrence(odds ratioZ5.85).Adjuvant self-calibration after BD not only reduced the recurrence rate from 85.4%in the non-self-calibration group to 15.1%in the self-calibration one(ped the overall stricture-free survival and FF parameters.

关键词： Balloon dilation Internal urethrotomy Recurrence Self-calibration Urethral stricture

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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 massive 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°Cemperatureegarding that,two test 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

Ultralong hydroxyapatite-based forward osmosis membrane for freshwater generation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and engineering 2024年第9期18卷 37-49页

作者： Mohamed Gamal Gomaa Hamdy Maamoun abdel-Ghafar Francesco Galiano Francesca Russo Alberto Figoli el-Sayed Ali abdel-Aal abdel-Hakim Taha Kandil Bahaa ahmed Salah Central Metallurgical Research and Development Institute(CMRDI) 11421 CairoEgypt Chemistry Department Faculty of ScienceHelwan University11795 CairoEgypt Institute on Membrane Technology(CNR-ITM) 87036 RendeItaly

Increasing global water shortages are accelerating the pace of membrane manufacturing,which generates many environmentally harmful *** challenges need a radical rethink of developing innovative membranes that can address freshwater production without generating environmentally harmful *** work utilized the synthesized ultra-long hydroxyapatite(UHA)by the solvothermal method using the green solvent oleic acid in preparing UHA-based forward osmosis *** membranes were developed using different loading ratios of graphene oxide(GO)by vacuum-assisted filtration *** prepared GO/UHA membranes were identified using X-ray diffraction,scanning electron microscope,Fourier-transform infrared spectroscopy,and X-ray photoelectron *** contact angle and pore size distribution were determined for the obtained GO/UHA *** obtained hierarchical porous structure in the prepared membranes with interconnected channels results in a stable water flux with reverse salt *** best water flux rate of 42±2 L·m^(–2)·h^(–1)was achieved using the 50 mg GO/UHA membrane,which is 3.3 times higher than the pristine membrane,and a reverse salt flux of 67 g·m^(-2)·h^(–1).The obtained results showed a promising capability of a new generation of sustainable inorganic-based membranes that can be utilized in freshwater generation by energy-efficient techniques such as forward osmosis.

关键词： forward osmosis ultra-long hydroxyapatite graphene oxide inorganic-based membrane

Influence of anodization conditions on deposition of Hydroxyapatite on α/β Ti alloys for Osseointegration: Atomic Force Microscopy Analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2024年

作者： Rania e.Hammam engie M.Safwat Soha A.abdel-gawad Madiha Shoeib Shimaa el-Hadad Faculty of engineering， Modern University for Technology and Information (MTI) Restorative and Dental Materials Department， National Research Centre Giza Chemistry Department， Faculty of Science， Cairo University Central Metallurgical Research and Development Institute P.O.87

Integrating titanium-based implants with the surrounding bone tissue remains challenging. This study aims to explore the impact of different anodization voltages （20-80V） on the surface topography of two-phase （α/β） Ti alloys and to produce TiO2films with enhanced bone formation abilities. Scanning electron microscopy coupled with energy dispersive spectroscopy （SeM-eDS） and atomic force microscopy （AFM） were applied to investigate the morphological， chemical， and surface topography of the prepared alloys and to confirm the growth of hydroxyapatite （HA） on their surfaces. Results disclosed that the surface roughness of TiO2films formed on Ti-6Al-7Nb alloys was superior to that of Ti–6Al–4V alloys. Ti-6Al-7Nb alloy anodized at 80 V had the highest yields of HA after immersion in SBF with enhanced HA surface coverage. The developed HA layer had a mean thickness of 128.38 ± 18.13 μm， suggesting its potential use as an orthopedic implantable material due to its promising bone integration and， hence， remarkable stability inside the human body.

关键词：

evaluating mechanism of banana pseudo-stem retting using seawater:A cost-effective surface pre-treatment approach

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

Journal of Bioresources and Bioproducts 2024年第3期9卷 322-335页

作者： Prince Hotor ahmed H.Hassanin Osbert Akatwijuka Mohamed A.H.Gepreel Mitsuo Yamamoto Yukie Saito ahmed abdel-Mawgood egypt-Japan University of Science and Technology Biotechnology ProgramAlexandria GovernorateNew Borg Al Arab 21934Egypt Alexandria University Department of Textile EngineeringAlexandria GovernorateBab Sharqi 5424041Egypt egypt-Japan University of Science and Technology Material Science and EngineeringAlexandria GovernorateNew Borg Al Arab 21934Egypt Graduate School of Agricultural and Life Sciences The University of TokyoBunkyo-KuTokyo 113-8657Japan

Retting has been employed to extract natural fibers from agricultural wastes as a biological and cost-effective approach for *** its global abundance,banana pseudo-stem is a promising agro-waste for lignocellulosic fiber *** this study,fibers were extracted from the pseudo-stems after being pre-treated under four conditions using seawater at room temperature for up to 35 d Bacterial isolation from the fresh seawater sample and screening for ligninolytic ability were *** load as well as laccase and manganese peroxidase enzyme activity profile assay during the retting duration were *** transform infrared(FT-IR)and X-day diffraction(XRD)analyses were also examined for both pre-treated and untreated extracted *** results shows that six out of the eight bacterial isolates had the ability to degrade *** treatments(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)recorded the highest viable bacterial load of 9.24×102 and 4.46×102 CFU,respectively,on the 14th day of the retting ***,the highest laccase and manganese peroxidase enzymes activity was recorded for(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)treatments in the second to the third *** FT-IR spectra of the pre-treated fibers revealed relative reductions in peaks attributed to polysaccharides and other amorphous substances for all retting *** XRD diffractogram revealed that the crystallinity index(CI)of pre-treated fibers increased in all seawater retting treatment ***,the CI for fibers pre-treated under enzymatic conditions were enhanced even after five *** analysis for selected bacterial isolates showed homology to sequences of Bacillus velezensis,Shewanella sp.L8–5,and Citrobacter amalonaticus and Bacillus subtilis j8 *** these findings,it was suggested that physical,biological,and chemical actions were collectively involved in the seawater retting process of banana ps

关键词： Seawater retting Banana pseudo-stem Natural fiber enzyme activity Colony forming unit

experimental validation of double-fed induction generator in oscillating water column using circulatory system-based optimization

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CLeAN eNeRGY 2024年第2期8卷 127-143页

作者： elnaghi, Basem e. Ismaiel, ahmed M. abdel-Kader, Fathy el Sayed Mohammed, Reham H. Abelwhab, M. N. Suez Canal Univ Elect Power & Machine Dept Ismailia Egypt Menoufia Univ Fac Engn Elect Machine & Power Dept Menoufia Egypt Suez Canal Univ Comp & Control Dept Ismailia Egypt

This paper validates the optimal operation for a grid-connected double-fed induction generator (DFIG) in an oscillating water column power plant (OWCPP). This study presents a novel optimization technique called the circulatory system-based optimization (CSBO) approach to develop six adaptive fuzzy logic controllers (AFLCs) with 30 parameters and compare them to chaotic-billiards optimization (C-BO) and genetic algorithm (GA). The proposed controller is also compared with a proportional-integral differential (PID) controller based on a self-adaptive global-best harmony search (SGHS). CSBO-based AFLCs are fully investigated under different scenarios and experimented with using a real-time interface DSP1104. The results of using CSBO-AFLCs revealed a fast time response, fast convergence, less overshoot and minimal error compared with those achieved with C-BO-AFLC, SGHS-PID and GA-AFLC during different case studies. The CSBO-based AFLCs ensure maximum power from the DFIG in an OWCPP and enhance dynamic response with very low errors. The results show that the CSBO shows better power tracking by 25% as compared with C-BO, by 45% when compared with the GA and by 56% when compared with PID. Moreover, the integral absolute errors of six controllers are investigated to demonstrate the feasibility of CSBO-AFLC. The root mean square of the errors of six controllers using CSBO is improved by 68.27% when compared with GA, by 22.57% when compared with C-BO and by 38.42% when compared with PID. These indicators demonstrate the feasibility of CSBO when compared with other algorithms with the same OWCPP. This paper validates the optimal operation of a grid-connected double-fed induction generator in an oscillating water column using a novel optimization technique called the circulatory system-based optimization approach. experiments using a real-time simulator demonstrate the feasibility of the approach when compared with other algorithms. Graphical Abstract

关键词： circulatory system-based optimization approach adaptive fuzzy logic controller grid-tied oscillating water column power plant maximum power point tracking WAVe eNeRGY-CONVeRSION DeSIGN OPTIMIZATION ALGORITHM CONTROLLeR TURBINe

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

在线全文

维普期刊数据库

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

Intravesical instillation of platelet-rich plasma for treatment of interstitial cystitis/bladder pain syndrome:A pilot study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Urology 2024年第1期18卷 49-54页

作者： ahmed S.el Hefnawy Mohamed Attya ahmed Hasan esam el Sawy Mohamed abdel-Razik Nasr el-Tabey Mansoura Urology and Nephrology Center Faculty of MedicineMansoura UniversityMansouraEgypt

Objective:The aim of this study was to evaluate the feasibility of intravesical instillation of platelet-rich plasma(PRP)to treat interstitial cystitis/bladder pain syndrome(IC/BPS).Materials and methods:Twenty PRP samples were tested in vitro for stability after exposure to urine samples with different pH.A pilot study involving 21 female patients with IC/BPS was conducted,and 6 weekly doses of autologous PRP(50 mL)were *** were followed up at the 2nd,4th,8th,and 12th weeks after terminating *** primary endpoint was the visual analog scale(VAS)for pain,and the secondary endpoints included the IC symptom index,IC problem index of the O'Leary-Sant questionnaire and global response assessment,urine culture,and *** was defined as a reduction in VAS by 30%or more compared with basal level,and adverse events were ***:The mean±SD of VAS was significantly reduced compared with basal level(4.4±2.6 vs.8.8±1.1,respectively,p=0.001).Meanwhile,80%of cases were considered successful,with a 50.1%reduction in the mean score compared with the basal *** mean±SD of IC symptom index and IC problem index significantly improved compared with the basal *** response assessment was markedly,moderately,and slightly improved in 2(10%),10(50%),and 5(25%)patients,respectively,and showed no change in 3(15%).Three patients had positive urine cultures at follow-up,but 1 withdrew after 2 sessions because of a lack of ***:Repeated intravesical instillation of PRP could be considered an effective and safe approach for treating IC/BPS.

关键词： Bladder pain syndrome Interstitial cystitis Platelet-rich plasma

Novel design of a compact tunable dual band wireless power transfer(TDB-WPT)system for multiple WPT applications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Information Technology & electronic engineering 2024年第4期25卷 616-628页

作者： Hany A.ATALLAH Rasha Hussein ahmed Adel B.abdel-RAHMAN Department of Communications and electronics Faculty of EngineeringSouth Valley UniversityQena 83523Egypt egypt-Japan University of Science and Technology Alexandria 21934Egypt

In this study we present the design and realization of a tunable dual band wireless power transfer(TDB-WPT)coupled resonator *** frequency response of the tunable band can be controlled using a surface-mounted *** transmitter(Tx)and the receiver(Rx)circuits are *** top layer contains a feed line with an impedance of 50Ω.Two identical half rings defected ground structures(HR-DGSs)are loaded on the bottom using a varactor *** propose a solution for restricted WPT systems working at a single band application according to the operating *** effects of geometry,orientation,relative distance,and misalignments on the coupling coefficients were *** validate the simulation results,the proposed TDB-WPT system was fabricated and *** system occupied a space of 40 mm×40 *** can deliver power to the receiver with an average coupling efficiency of 98%at the tuned band from 817 to 1018 MHz and an efficiency of 95%at a fixed band of 1.6 GHz at a significant transmission distance of 22 *** results of the measurements accorded well with those of an equivalent model and the simulation.

关键词： Defected ground structure(DGS) Surface-mounted Tunable dual band wireless power transfer(TDB-WPT) Varactor