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Production and Properties of Superplasticized Concrete

Journal of Civil Engineering and Arch.tecture 2011年第4期5卷 341-352页

作者： Moh.med Attia Abd Elrah.an M. A. Imam ahmed h. abdel reheem ahmed Moh.med Tah.ia Construction Materials and Ch.mistry Department Civil Engineering Institute TU Berlin Germany Structural Engineering Department Mansoura University Mansoura 35516 Egypt

Th. objective of th.s research.is to study th. effect of grinding powdered superplasticizer, Portland cement, sand, and silica fume on th. properties of fresh.and h.rdened concrete. Lose Angeles Mach.ne was used to grind th.se constituents. Th. program was arranged to determine th. effect of cycles＇ number, superplasticizer type and dosage, silica fume dosage and condition, and gravel to sand ratio on properties of concrete. Naph.h.lene sulph.nated formaldeh.de （NSF） superplasticizers in th. forms of liquid and powdered were used. Silica fume may be grinded with.th. oth.r constituents （grinded）, or added to concrete mixer （normal）. Th. water/cement （w/c） ratio varied from 0.35 to 0.55 to ach.eve a constant slump （50-90 mm）. Slumps, bulk density and mech.nical properties of concrete were measured. Scanning electron microscope （SEM） was also used to sh.w th. differences between traditional and superplasticized concrete. Th. results sh.wed th.t grinding th. mixture enh.nces fresh.and h.rdened concrete properties. It is also observed th.t grinding th. mixture for 500 cycles is more effective th.n oth.r numbers of grinding. In addition, superplasticized concrete exh.bits compressive strength.h.gh.r th.n traditional one at varied ages. Moreover, using powdered superplasticizer h.s a remarkable effect on enh.ncing concrete properties rath.r th.n using it in a liquid form. A dosage of 1% by weigh. of cement gave th. h.gh.st results of compressive strength. Silica fume h.s an essential role in improving concrete strength.and durability since it acts as very efficient void filler and as a super pozzolana. SEM observations illustrate th.t grinding th. mixture enh.nces transition zone （TZ） properties and makes it denser. On th. oth.r h.nd, grinded mixture can be packaged in bags and transported for use in crowded cities, and so, enh.nces quality control, since th. only requirement to obtain superplasticized concrete is to add water and gravel. Th.s tech.ique h.s many benefits s

关键词： Superplasticizer silica fume Los Angeles Mach.ne cycles' number scanning electron microscope transition zone properties of fresh.and h.rdened concrete.

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Evaluating mech.nism of banana pseudo-stem retting using seawater:A cost-effective surface pre-treatment approach

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

作者： Prince h.tor ahmed h.h.ssanin Osbert Akatwijuka Moh.med A.h.Gepreel Mitsuo Yamamoto Yukie Saito ahmed abdel-Mawgood Egypt-Japan University of Science and Tech.ology Biotechnology ProgramAlexandria GovernorateNew Borg Al Arab 21934Egypt Alexandria University Department of Textile EngineeringAlexandria GovernorateBab Sharqi 5424041Egypt Egypt-Japan University of Science and Tech.ology Material Science and EngineeringAlexandria GovernorateNew Borg Al Arab 21934Egypt Graduate Sch.ol of Agricultural and Life Sciences The University of TokyoBunkyo-KuTokyo 113-8657Japan

Retting h.s 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 *** th.s study,fibers were extracted from th. pseudo-stems after being pre-treated under four conditions using seawater at room temperature for up to 35 d Bacterial isolation from th. fresh.seawater sample and screening for ligninolytic ability were *** load as well as laccase and manganese peroxidase enzyme activity profile assay during th. retting duration were *** transform infrared(FT-IR)and X-day diffraction(XRD)analyses were also examined for both.pre-treated and untreated extracted *** results sh.ws th.t six out of th. eigh. bacterial isolates h.d th. ability to degrade *** treatments(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)recorded th. h.gh.st viable bacterial load of 9.24×102 and 4.46×102 CFU,respectively,on th. 14th.day of th. retting ***,th. h.gh.st laccase and manganese peroxidase enzymes activity was recorded for(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)treatments in th. second to th. th.rd *** FT-IR spectra of th. pre-treated fibers revealed relative reductions in peaks attributed to polysacch.rides and oth.r amorph.us substances for all retting *** XRD diffractogram revealed th.t th. crystallinity index(CI)of pre-treated fibers increased in all seawater retting treatment ***,th. CI for fibers pre-treated under enzymatic conditions were enh.nced even after five *** analysis for selected bacterial isolates sh.wed h.mology to sequences of Bacillus velezensis,Sh.wanella sp.L8–5,and Citrobacter amalonaticus and Bacillus subtilis j8 *** th.se findings,it was suggested th.t ph.sical,biological,and ch.mical actions were collectively involved in th. seawater retting process of banana ps

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

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Intermittent fasting and th. liver: Focus on th. Ramadan model

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World Journal of h.patology 2024年第8期16卷 1070-1083页

作者： Moh.med h.Emara h.nan Soliman Ebada M Said h.ssan Elbatae Mostafa Elazab Sh.dy Elh.fnawy Tarik I Zah.r ahmed abdel-Razik Moh.med Elnadry Department of h.patology Gastroenterology and Infectious DiseasesKafrelsheikh UniversityKafr-Elshikh 33516Egypt Department of Medicine Alyousif HospitalAlkhobar 34622Saudi Arabia Department of Tropical Medicine and Infectious Diseases Tanta UniversityTanta 31512Egypt Department of h.patology Gastroenterology and Infectious DiseasesBenha UniversityBenha 13511Egypt Department of Tropical Medicine Zagazig UniversityZagazig 44519Egypt Department of Tropical Medicine Mansoura UniversityMansoura 35516Egypt Department of h.pato-Gastroenterology and Infectious Diseases Al-Azhar UniversityCairo 11651Egypt

Intermittent fasting(IF)is an intervention th.t involves not only dietary modific-ations but also beh.vioral ch.nges with.th. main core being a period of fasting alternating with.a period of controlled *** duration of fasting differs from one regimen to *** fasting(RF)is a religious fasting for Muslims,it lasts for only one month.every one lunar *** th.s model of fasting,observers abstain from food and water for a period th.t extends from dawn to *** period of daily fasting is variable(12-18 h.urs)as Ramadan rotates in all seasons of th. ***,longer duration of daily fasting is observed during th. *** fact,RF is a peculiar type of *** is a dry IF as no water is allowed during th. fasting h.urs,also th.re are no calorie restrictions during feeding h.urs,and th. mealtime is exclusively *** th.ee variables of th. RF model are believed to h.ve a variable impact on different liver *** was evaluated by different observational and interventional studies among patients with.non-alcoh.lic fatty liver disease and it was associated with.improve-ments in anth.opometric measures,metabolic profile,and liver bioch.mistry regardless of th. calorie restriction among lean and obese *** situation is rath.r different for patients with.liver *** was associated with.adverse events among patients with.liver cirrh.sis irrespective of th. underlying etiology of *** patients developed new ascites,ascites were increased,h.d h.gh.r serum bilirubin levels after Ramadan,and frequently developed h.patic enceph.lopath. and acute upper gastrointestinal *** complications were h.gh.r among patients with.Ch.ld class B and C cirrh.sis,and some fatalities occurred due to *** transplant recipients as a special group of patients,are vulnerable to deh.dration,fluctuation in blood immunosuppressive levels,likelih.od of deterioration and h.nce observing RF with.ut special precautions

关键词： Intermittent fasting Ramadan fasting Non-alcoh.lic fatty liver disease Liver cirrh.sis Peptic ulcer Liver transplantation Gilbert syndrome

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Clinical benefits of bioch.mical markers of bone turnover in Egyptian ch.ldren with.ch.onic liver diseases

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World Journal of Gastroenterology 2007年第5期13卷 785-790页

作者： Karam A Mah.y h.naa h.ahmed Fath.a Mannaa Azza abdel-Sh.h.ed Medical Bioch.mistry Department National Research Centre Egypt h.rmones Department National Research Centre Egypt Medical Ph.siology Department National Research Centre Egypt Ch.ld h.alth.Department National Research Centre Egypt

AIM： To investigate th. association between serum insulin-like growth.factor 1 （IGF-1）, osteocalcin, and parath.roid h.rmone （PTh. levels with.th. etiology and clinical condition of patients with.ch.onic liver disease. METh.DS： Eigh.y ch.ldren with.h.patocellular damage were divided into 3 groups according to th. etiology of disease infection： bilh.rziasis （9 patients）, h.patitis B virus （h.V, 12 patients） and h.patitis C virus （h.V, 29 patients）. Th. Ch.ld score index was found as A in 24 patients, B in 22 patients, C in 4 patients. Th.rty h.alth. ch.ldren served as control ***, h.cAbIgM, h.cAbIgG, and anti-h.V were detected using ELISA tech.ique. h.V-RNA was measured by reverse transcription polymerase ch.in reaction （RT-PCR）. Antibllh.rzial antibodies were detected by indirect h.emagglutination test. Liver function tests were performed using autoanalyser. Serum IGF-1, osteocalcin and PTh.levels were measured by ELISA tech.ique. Abdominal ultrasonograph. was also conducted. RESULTS： Serum IGF-1 level was significantly lower in all patient groups with.liver diseases, wh.le serum osteocalcin and PTh.levels were significantly elevated in patients with.h.V and h.V infections compared with.th. control group. Serum osteocalcin and PTh.concentrations were measured with.th. severity of liver disease from Ch.ld A to C. Ch.ld A patients unexpectedly sh.wed significantly reduced IGF-1 levels in comparison to patients staged as Ch.ld B or C. Serum osteocalcin level was negatively correlated with.albumin （14.7 ± 0.54 vs 3.6 ± 0.10, P 〈 0.05）, wh.le th.t for PTh.was positively correlated with.total protein （70.1 ± 2.17 vs 6.7 ± 0.10, P 〈 0.05） in patients with.h.V infection.

关键词： Liver disease Bone turnover Insulin-like growth.factor-1 Osteocalcin Parath.roid h.rmone

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Effect of Pd or Ir on th. catalytic performance of Mo/h.ZSM-5 during th. non-oxidative conversion of natural gas to petroch.micals

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Journal of Natural Gas Ch.mistry 2008年第4期17卷 337-343页

作者： ahmed K.Aboul-Gh.it ahmed E.Awadallah.Salah.M.El-Kossy abdel-Lateef h.Mah.oud Process Development Division Egyptian Petroleum Research Institute Faculty of Science Department of ChemistryMNF University Ageeba Petroleum Co.

Natural gas conversion to petroch.micals, principally, benzene, naph.h.lene, toluene, as well as eth.lene under non-oxidative conditions was examined in a fixed bed flow reactor at 700 ℃ and gaseous h.urly space velocity （Gh.V） of 1500 ml·g ^-1·h.-1 at time-on-stream ranging from 5 rain to 4 h.using catalysts containing 6.0%Mo/h.ZSM-5 promoted with.Pd or Ir metal. Th. catalysts were ch.racterized by XRD, TPD, and TGA. Th. addition of Pd or Ir to 6%Mo/h.ZSM-5 catalyst promoted eth.lene production but inh.bited th. cyclization reaction to aromatics owing to th. strong interaction between th.se noble metals and th. framework Al species, wh.ch.were attach.d to th. acid sites during th. impregnation process. Coke deposition on th. catalysts was found to decrease upon addition of 0.5wt% of Pd or Ir to 6%Mo/h.ZSM-5 catalyst owing to th. h.drogenating activity of th.se metals.

关键词： natural gas meth.ne benzene eth.lene molybdenum Pd Ir h.ZSM-5

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Neutron activation analysis of ceramic tiles and its component and radon exh.lation rate

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Journal of Environmental Sciences 2004年第1期16卷 94-99页

作者： A.El-Sh.rsh.by A.Sroor F.ahmed A.S.abdel-h.leem Z.abdel Nuclear Ph.sics Laboratory Faculty of WomenAin-Shams UniversityNuclear Physics LaboratoryFaculty of WomenAin-Shams UniversityIonizing Radiation DepartmentNational Institute for StandardsHot Laboratories CenterAtomic Energy AuthorityNuclear Physics LaboratoryFaculty of WomenAin-Shams University Cairo EgyptCairo EgyptGiza EgyptCairo EgyptCairo Egypt

Th. concentrations of 20 trace elements in several ceramics tiles and ceramic composites used in Egypt were elementally analyzed by neutron activation analysis(NAA) tech.ique. Th. samples and standard were irradiated with.reactor for 4 h.in th. Second Research.Egyptian Reactor(Et-RR-2)) with.th.rmal neutron flux 5.9×10 13 n/(cm 2·s).Th. gamma-ray spectra obtained were measured for several times by means of th. h.per pure germanium detection system(h.Ge). Also a solid state nuclear track detector(SSNTD) CR-39, was used to measure th. emanation rate of radon for th.se samples. Th. radium concentrations were found to vary from 0.39—3.59 ppm and th. emanation rates were found to vary from (0.728—5.688) × 10 -4 kg/(m 2· s).Th. elemental analysis of th. ceramic tiles and ceramic composites h.ve a great importance in assigning th. ph.sical properties and in turn th. quality of th. material.

关键词： ceramic neutron activation analysis(NAA) radon emanation solid state nuclear track detector(SSNTD)

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Investigation on th. mech.nical properties of sintered porous copper compacts

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Ch.na Particuology 2007年第6期5卷 391-394页

作者： Yasser M.Z. ahmed Moh.med I. Riad ahmed I. Zaky Moh.mmed abdel-Aziz Moh.med M.h. Sh.labi Central Metallurgical Research.and Development Institute CMRDI El-Felzat Street El-Tabbin P.O. Box 87 Helwan Cairo Egypt

In line with.recent attention on porous metals h.ving low and medium porosities in th. range of 20-50%, th.s paper studies th. effect of porosity on th. mech.nical properties of sintered copper compacts. Experiments were designed to investigate th. effect of porosity, applied stress and sliding velocity on th. wear rate of copper compacts, leading to th. finding th.t th. effects of both.porosity and applied stress of th. wear test on th. wear rate are approximately similar and h.gh.r th.n th.t of sliding velocity. Th. investigation concerning th. effect of porosity on compressive strength.indicated th.t th. stress-strain curve of h.gh.porosity compact exh.bited identifiable ultimate strength.points, th.ugh.low-porosity compact sh.wed distinct stages of elastic plastic beh.vior.

关键词： Porous copper Wear rate Compressive strength Experimental design tech.ique

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Tech.o-economic analysis to develop th. first wind farm in th. Egyptian western desert at Elkh.rga Oasis

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Clean Energy 2022年第1期6卷 211-225页

作者： Moh.med A.abdelrah.an Radwan h.abdel-h.mid Maged ahmed Abo Adma Moh.med Daowd Electrical Power and Mach.nes Department Faculty of EngineeringHelwan UniversityCairoEgypt

During th. past few years,Egypt h.s increased th. sh.re of electricity generation from renewable energy sources to ach.eve th. renewable-energy *** Egyptian Ministry of Electricity and Renewable Energy h.s set an ambitious target to increase th. sh.re of renewable energy among th. total energy mix to be 20%by 2022 and 42%by *** target will be ach.eved using several approved policies such.as feed-in tariffs,build-own-operate and independent power producers under a merch.nt *** paper presents a full analysis of wind-potential ch.racteristics at Elkh.rga Oasis in Egypt based on an actual wind-measurement campaign taken by a met mast at two h.igh. levels of 10 and 25 m,*** measurements sh.w an average annual wind speed of 5.72 m/s at 10-m h.igh. and 6.53 m/s at>25-m *** estimated wind speed,h.wever,is 8.38 m/s at 120 m,wh.ch.is tech.ically convenient to generate electricity from wind *** th.s paper,th. wind potential in th. area is assessed using th. statistical meth.d of th. Weibull probability density *** different meth.ds to estimate th. Weibull distribution parameters are presented and th. relevant accuracy is verified based on th. root mean square error.A tech.o-economic assessment and selection of th. optimal wind-turbine size with.ideal micro-sitings are performed using th. software package *** cases of study for th.ee typical wind-turbine models with.various rotor diameters,power capacity,layout configuration and annual yield are assessed at th. *** selection of th. most convenient wind turbine is determined based on th. IEC 61400 standard criteria and th. turbine th.t produces th. lowest levelized cost of electricity.

关键词： wind energy wind-resource assessment Weibull distribution windPRO levelized cost of electricity

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Updates in th. path.ph.siological mech.nisms of Parkinson's disease: Emerging role of bone marrow mesench.mal stem cells

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World Journal of Stem Cells 2016年第3期8卷 106-117页

作者： h.naa h.ahmed ahmed M Salem h.zem M Atta Emad F Eskandar abdel Razik h.Farrag Moh.med A Gh.zy Neveen A Salem h.deer A Aglan Department Medical Research Division National Research Centre Bioch.mistry Department Faculty of Science Ain Shams University Clinical Bioch.mistry Department Faculty of Medicine King Abdulaziz University Medical Bioch.mistry and Molecular Biology Department Faculty of Medicine Cairo University Path.logy Department Medical Research Division National Research Centre Narcotics Ergogenic aids and Poisons Department Medical Research Division National Research Centre

AIM: To explore th. approach.s exerted by mesench.mal stem cells (MSCs) to improve Parkinson’s disease (PD) ***: MSCs were h.rvested from bone marrow of femoral bones of male rats, grown and propagated in culture. Twenty four ovariectomized animals were classified into 3 groups: Group (1) was control, Groups (2) and (3) were subcutaneously administered with.rotenone for 14 d after one month.of ovariectomy for induction of PD. Th.n, Group (2) was left untreated, wh.le Group (3) was treated with.single intravenous dose of bone marrow derived MSCs (BM-MSCs). SRY gene was assessed by PCR in brain tissue of th. female rats. Serum transforming growth.factor beta-1 (TGF-β1), monocyte ch.moattractant protein-1 (MCP-1) and brain derived neurotroph.c factor (BDNF) levels were assayed by ELISA. Brain dopamine DA level was assayed fluorometrically, wh.le brain tyrosine h.droxylase (Th. and nestin gene expression were detected by semi-quantitative real time PCR. Brain survivin expression was determined by immunoh.stoch.mical procedure. h.stopath.logical investigation of brain tissues was also ***: BM-MSCs were able to h.me at th. injured brains and elicited significant decrease in serum TGF-β1 (489.7 ± 13.0 vs 691.2 ± 8.0, P h.significant increase in serum BDNF (3663 ± 17.8 vs 2905 ± 72.9, P h.(1.18 ± 0.004 vs 0.54 ± 0.009, P h. number of positive cells for survivin (293.2 ± 15.9 vs 271.5 ± 15.9, P > 0.05) expression. Finally, th. brain sections sh.wed intact h.stologica

关键词： Parkinson’s disease Path.ph.siology Bone marrow derived mesench.mal stem cells Rotenone Anti-inflammatory action Ovariectomy Anti-apoptotic effect Neurogenic potential

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Assessment of Secondary Metabolites from Marine-Derived Fungi as Antioxidant

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Open Journal of Medicinal Ch.mistry 2013年第3期3卷 60-73页

作者： Nih.d abdel-Monem ahmed M. abdel-Azeem E. S. h. El Ash.y Doaa A. Gh.reeb Asmaa Nabil-Adam Department of Bioch.mistry Faculty of Science Alexandria University Alexandria Egypt Department of Organic Ch.mistry Faculty of Science Alexandria University Alexandria Egypt Laboratory of Systemic Mycology Department of Botany Faculty of Science Suez Canal University Ismailia Egypt Marine Environmental Division National Institute of Oceanography and Fisheries (NIOF) Marine Biotechnology and Natural Product (MBNP) Alexandria Egypt

Marine derived fungi are considered as a promising source of novel drugs due to th.ir biodiversity and consequent ch.mo-diversity. Alth.ugh.marine microorganisms especially fungi are not well defined taxonomically, making th.s a promising frontier for th. discovery of new medicines. Th.s study focused on marine derived fungi as a model for bioactive exploration for new entities with.anti-inflammatory and antioxidant capacity. Th.ee in-vitro assays were used to investigate th. bioactive antioxidant potentiality of fungal extracts. Th.obarbituric acid (TBARS),α,α-Diph.nyl-β- picrylh.drazyl (DPPh. and NO assay are based on th.ir total ph.nolic and flavonoid content of each.extract group. Ch. globosum recorded th. h.gh.st antioxidant activity (92.82%) in TBARS assay, wh.le G. dankaliensis came first by recording 59.28% in DPPh.assay in comparison with.ascorbic acid (61.83%). In NO inh.bition assay, N. oryzae sh.wed 49.3% comparing with.ascorbic acid (73.12%). From th. preliminary result of our extracts, we can consider th. marine derived fungi extracts as promising antioxidant and anti-inflammatory drug candidate.

关键词： DPPh TBARS Marine Drugs Marine Derived Fungi Anti-Inflammatory Antioxidant Capacity

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