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Alternating current characterization of nano-Pt(Ⅱ)octaethylporphyrin(PtOEP) thin film as a new organic semiconductor

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Chinese Physics B 2016年第6期25卷 426-432页

作者： m Dongol m m el-Nahass A el-Denglawey A A Abuelwafa T soga Nano and Thin Film Laboratory Physics DepartmentFaculty of ScienceSouth Valley University Physics Department Faculty of EducationAin Shams University Physics Department Faculty of Applied Medical ScienceTaif University Department of Frontier materials Nagoya Institute of Technology

Alternating current（AC） conductivity and dielectric properties of thermally evaporated Au/Pt OEP/Au thin films are investigated each as a function of temperature（303 K–473 K） and frequency（50 Hz–5 mHz）.The frequency dependence of AC conductivity follows the Jonscher universal dynamic *** AC-activation energies are determined at different *** is found that the correlated barrier hopping（CBH） model is the dominant conduction *** variation of the frequency exponent s with temperature is analyzed in terms of the CBH *** barrier height Wm,hopping distance Rω,and the density of localized states N（EF） are valued at different *** constant ε1（ω,T） and dielectric loss ε2（ω,T） are discussed in terms of the dielectric polarization *** dielectric modulus shows the non-Debye relaxation in the *** extracted relaxation time by using the imaginary part of modulus（m’’）is found to follow the Arrhenius law.

关键词： PtOEP thin films AC conductivity dielectric constants organic semiconductors solar cell nano materials

Investigation of charge transfer complexes formed between 3,3′-dimethylbenzidine (o-toluidine) donor and DDQ, p-chloranil and TCNQ as π-acceptors

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Chinese science Bulletin 2011年第19期56卷 1993-2000页

作者： REFAT moamen s el-mETWALLY Nashwa m Department of Chemistry Faculty of Science Port Said University Department of Chemistry Faculty of Science Taif University Department of Chemistry Faculty of Education King Khaled University

Charge-transfer (CT) complex of o-toluidine (o-tol) with the π-acceptor tetrachloro-p-benzoquinone (p-chloranil; CHL) has been synthesized and characterized, along with the products of the elimination reaction of o-toluidine (o-tol) with 2,3-dichloro-5,6dicyano-p-benzoquinone (DDQ) and 7,7,8,8-tetracyanoquinodimethane (TCNQ). Their properties and structures have been investigated using electronic absorption and IR spectroscopy as well as elemental analyses of the isolated compounds. The o-tol/p-CHL CT complex is shown to consist of a CHL radical anion and o-tol + radical cation. The formations of all three compounds result in the appearance of new UV-Vis spectral bands that peaked in intensity at a stoichiometric ratio of 1 : 1. 1 H-NmR and mass spectra were used to confirm the formation of the o-tol/DDQ and o-tol/TCNQ products. The new 7,8-dicyano-7′,8′-o-toluidilequinodimethane and 2,3-dichloro-5-cyano-6-o-toluidil-p-benzoquinone products resulted from the rapid reaction of o-tol with TCNQ and DDQ, respectively. Thermogravimetric studies showed that the CT-complex decomposes in three steps whereas the new compounds decompose in a single step. Thermodynamic parameters were computed from the thermal decomposition data.

关键词：电荷转移复合物四氯对苯醌 TCNQ DDQ 甲基苯胺受体二甲基电子吸收光谱

Production of geopolymer composites enhanced by nano‐kaolin material

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Journal of Advanced Ceramics 2015年第4期4卷 245-252页

作者： mahmoud m.HAssAAN Hisham m.KHATER medhat s.el-mAHLLAWY Abdeen m.el NAGAR Al Azhar University Nasr CityCairoEgypt Housing and Building National Research Centre(HBRC) 87 El-Tahrir St.DokkiGizaP.O.Box 1770CairoEgypt

Nowadays kaolin raw material is usually used to produce nano-kaolin for geopolymer enhancement by using firing *** the present study,kaolin used was taken from the Naqus Formation(Cambro-Ordovician age),west of Gabal el Gunna,sinai,***-kaolin material is an ultrafine material and was prepared from the taken kaolin by the firing process at 800 for 2℃h with a heating rate of 5/*** mixes were prepared and their laboratory specimens were made℃and cured up to 90 *** cooled slag was used as starting material,and sodium hydroxide and sodium silicate were used in the study as activators for the used *** formed geopolymer mixes with different ratios(1%,1.5%,3%,5%,and 7%)of nano-kaolin as a partial replacement for the raw kaolin were *** Ace super plasticizer was added in the ratio of 4%from the dry weight to ensure good dispersing of the used nano *** showed that increasing the percentage of nano-kaolin up to 3%results in an enhancement in the mechanical properties as compared with the control mix up to 90 days of curing,while higher ratios are not preferable where they lead to agglomeration of the added nano materials and matrix dilution.

关键词： geopolymer nano-kaolin sodium silicate slag

Plasma ignition threshold disparity between silver nanoparticle-based target and bulk silver target at different laser wavelengths

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Plasma science and Technology 2019年第1期21卷 63-71页

作者： A m el sHERBINI m m HAGRAss m R m RIZK E A el-BADAWY Laboratory of Laser and New materials Faculty of Science Cairo University Faculty of Engineering Electrical Engineering Department Alexandria University

Plasma ignition threshold of nanoparticle-based and bulk silver targets was measured in air. The plasma was initiated by a Nd:YAG laser at wavelengths of 355, 532, and 1064 nm. The plasma ignition was monitored utilizing the prominent Ag I line at 546.5 nm. Lower ignition thresholds of the nanoparticle-based silver target were estimated at 0.4?±?0.02, 0.34?±?0.04, and 0.27?±?0.035 J cm^(-2) coupled with the different laser wavelengths, respectively. In contrast, the bulk silver target plasma exhibited an order of magnitude higher ignition threshold. A three orders of magnitude enhanced emission intensity from the nano-based target over the bulk target was achieved at lower levels of laser irradiation. A reduction of the thermal diffusion length of the nanosilver was assumed in order to theoretically predict this reduction in the plasma threshold. In addition, the effect of self-reversal on the resonance lines was taken into consideration.

关键词： NelIBs enhancement nanosilver laser plasma threshold

Transport Properties of Bi_2s_3 single Crystals

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Journal of materials science & Technology 2008年第5期24卷 757-760页

作者： H.T.shaban m.m.Nassary m.s.el-sadek Physics Department Faculty of ScienceSouth Valley Univ.QenaEgypt.

Bi2s3 single crystals were grown by using a modification of Bridgman method. measurements of the electrical conductivity, Hall effect and thermoelectric power （TEP） were preformed in two crystallographic directions （parallel and perpendicular to the c-axis）. The measurements showed that the electrical conductivity, Hall mobility, and seebeck coefficient have anisotropic nature. From these measurements some physical parameters were estimated and the crystals showed n-type of conduction mechanism. Also, values of the energy gap were found to be different in the two directions.

关键词： Bi2s3 Hall effect Thermoelectric power electrical conductivity

Brain-penetrating neurotrophic factor mimetics: HER-096 as a disease-modifying therapy for Parkinson’s disease

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Neural Regeneration Research 2025年第4期20卷 1094-1095页

作者： Natalia Kulesskaya Kira m.Holmström Henri J.Huttunen Herantis Pharma Plc EspooFinland

Neurotrophic factors as a therapeutic approach in neurodegenerative diseases:A major unmet need in the field of central nervous system diseases is disease-modifying *** for decades there have been various symptomatic treatments available to alleviate the symptoms of the disease,disease-modification,*** that stop,significantly delay,or reverse the progression of the disease,has been turned out to a difficult goal to achieve.

关键词： diseases treatment therapeutic

Exponentiated Generalized Inverse Flexible Weibull Distribution:Bayesian and Non-Bayesian Estimation Under Complete and TypeⅡCensored samples with Applications

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Communications in mathematics and statistics 2022年第3期10卷 413-434页

作者： m.el-morshedy m.s.eliwa A.el-Gohary Ehab m.Almetwally R.el-Desokey Department of mathematics College of Science and Humanities in Al-KharjPrince Sattam Bin Abdulaziz UniversityAl-Kharj 11942Saudi Arabia Department of mathematics Faculty of ScienceMansoura UniversityMansoura 35516Egypt Faculty of Business Administration Delta University of Science and TechnologyMansouraEgypt Faculty of Graduate studies for statistical Research Cairo UniversityGiza 12613Egypt

In this paper,a new 4-parameter exponentiated generalized inverse flexible Weibull distribution is *** of its statistical properties are *** aim of this paper is to estimate the model parameters via several approaches,namely,maximum likelihood,maximum product spacing and *** to Bayesian approach,several techniques are used to get the Bayesian estimators,namely,standard error function,Linex loss function and entropy loss *** estimation herein is based on complete and censored *** Chain monte Carlo simulation is used to discuss the behavior of the estimators for each ***,two real data sets are analyzed to obtain the flexibility of the proposed model.

关键词： Weibull distribution Hazard rate function maximum likelihood estimation maximum product spacing estimation Bayesian estimation Censored samples simulation

Geochemistry, mineralogy, and radioactivity of the Abu Furad Area, Central Eastern Desert, Egypt

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Acta Geochimica 2019年第2期38卷 307-326页

作者： A.m.el mezayen E.K.Abu Zeid W.s.Hosny m.G.el-Feky s.m.Omar s.A.Taalab Geology Department Faculty of Science Al Azhar University Nuclear material Authority Cairo Egypt

Abu Furad is in the Central Eastern Desert,Egypt. It comprises metasediments, metavolcanics,metagabbros, syn-to late-orogenic granites, and post-orogenic granites, in addition to numerous dykes and veins of different shapes and composition invading all the older rocks cropping out in the study area. Field, petrographic,mineralogical, and chemical investigations led to the classification of Abu Furad granites as quartz diorite, tonalite,granodiorite, and *** oxide and trace element data revealed that the syn-to late-orogenic granites and post-orogenic granites are peraluminous. syn-to lateorogenic granites originated from calc-alkaline volcanic arc–related magma; while the post-orogenic granites(syenogranite) are highly fractionated, calc-alkaline granite from a within plate regime. Radiometrically, the studied quartz diorite, tonalite, and granodiorite had lower uranium and thorium contents and higher eU/eTh ratios than the syenogranites. This may indicate that the syn-to late-orogenic rocks originated from sources depleted in these elements. The average e Th/eU ratio of syenogranites was higher than that of average continental crust, suggesting that the syenogranites are relatively depleted in U. The studied altered syenogranites were strongly enriched in U and Th compared to the Earth's crust. On the other hand, the average of e U in pegmatites is lower than the global average for uraniferous pegmatites. The most recorded accessory minerals in the altered syenogranites were thorite, fergusonite, samarskite, columbite, zircon, monazite, xenotime,apatite, fluorite, sphene, atacamite, and malachite, in addition to chromium and nickel inclusions.

关键词： Hydrothermal alterations major oxide and trace elements Radiometry mineralogy Geochemistry Altered syenogranites Egypt

Physico-analytical studies on salicylaldehyde Thiosemicarbazone Complexes

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Journal of materials science & Technology 1998年第5期14卷 434-440页

作者： Abo el Fetoh, s.H. Abd el-Kareem, A.T. Wassel, m.A. Eid, A.E. Faculty of Girls-Ain shams University Egypt National Research Centre Egypt Faculty of science El-Menoufia University Egypt Faculty of science Al-Azhar University Egypt

The complexes of salicylaldehyde thiosemicarbazone with Pd, Cu and Ru were prepared. The prepared complexes were characterized by spectroscopic, element and thermal analyses and D.C. conductivity measurements. The antimicrobial activity of all the prepared compounds against gram-positive, gram-negative and fungi was studied. From these studies, it has been obtained that the ligand is bonded to the metals through O, N and s, but to palladium in [Pd (H//2L//2)] Cl//2 only through N and O. Biological studies confirm that the organic effect on both gram-positive and gram-negative bacteria is very weak and their complexes have no effect on fungi, but Cu-complex has strong influence on both types of bacteria. (Edited author abstract) 22 Refs.

关键词： metallorganic polymers