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An ex-Press implant versus trabeculectomy in a fibrotic bleb with late failure after previous trabeculectomy

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International Journal of Ophthalmology(english edition) 2021年第3期14卷 383-387页

作者： Faried Wagdy Tharwat h.Mokbel hisham elsorogy Ahmed Alnagdy Dina abd elfattah abd-elmonem A.elhesy Menofia University hospital Menofia UniversityMenofia 32511Egypt Mansoura Ophthalmic Center Faculty of MedicineMansoura UniversityMansoura 35516Egypt

AIM: To compare the outcome of an ex-Press implant and subscleral trabeculectomy(SST) in the management of glaucoma after previous trabeculectomy on a fibrotic ***: This randomized prospective study included 28 eyes from 28 patients(age range: 42-55 y) with primary open angle glaucoma(POAG) presented with elevated intraocular pressure(IOP) with fibrotic bleb despite previous SST for more than 4 mo. The eyes enrolled in the study were divided into two groups: group I(subjected to ex-Press implant surgery) and group II [subjected to SST with mitomycin C(MMC)]. The follow-up continued one year after surgery to evaluate IOP, visual acuity(VA), visual field(VF), and postoperative complications. ReSULTS: A significant decrease in IOP was found in both groups with a higher reduction in ex-Press implant surgery with the mean IOP of 14.50 mm hg(P=0.001), while the SST group recorded the mean IOP of 16.50 mm hg(P=0.001) after one year. however, the difference between the two groups in terms of the decrease in IOP was insignificant. Fewer postoperative complications were recorded in the ex-Press implant surgery and more cases requiring further anti-glaucomatous medications were seen in the SST group. Both groups showed stability in terms of VA and ***: ex-Press implant surgery and SST with MMC are two surgical alternatives for controlling IOP in late failure that occurs more than 4 mo after previous SST with a fibrotic bleb. however, ex-Press shunt is a safer surgery with fewer complications.

关键词： ex-Press implant trabeculectomy glaucoma fibrotic bleb

Permutation-substitution image encryption scheme based on a modified chaotic map in transform domain

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Journal of Central South University 2017年第9期24卷 2049-2057页

作者： Ramadan Noha Ahmed hossameldin h el-khamy Said e abd el-Samie Fathi e Faculty of electronic engineering Menofia University Faculty of engineering Alexandria University

A new chaotic image encryption scheme based on permutation and substitution in the Fourier domain is *** Fourier Transform(FRFT)is used before the encryption scheme to get a large degree of *** permutation is achieved by Baker map and the substitution by a key-related-to-plain-image algorithm based on the modified Logistic *** of the Logistic map is developed to increase the space of the encryption key,and hence increase the *** key of the encryption algorithm dependents on the plain image,and thus,the cipher image is sensitive to both the initial key and the plain image to resist known-plaintext and chosen plaintext *** key space is large and hence the algorithm can effectively resist brute-force *** proposed scheme is examined using different performance evaluation metrics and the results prove that the proposed scheme is highly secure,and it can effectively resist different attacks.

关键词： Backer map chaotic encryption fractional Fourier transform (FRFT) modified Logistic map

Oxidation Resistance of the Aluminide Coating Formed on Carbon Steels

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Journal of Materials Science & Technology 1997年第5期13卷 383-388页

作者： Soliman, h.M. Ohamed, K.e. abd el-Azim, M.e. hammad, F.h. Metallurgy Dept. Atomic Energy Authority Cairo Egypt

Low and medium carbon steels were aluminized by the pack aluminizing technique using halideactivated pure-Al and Fe-Al packs. The effect of mixture composition, aluminizing temperatureand time and C content of the steel substrate on the structure and thickness of the aluminidelayer, and on the oxidation resistance was investigated. The optimum oxidation resistance canbe achieved with a low carbon steel substrate when the intermetallic phases Fe3Al and FeAlform the surface of the aluminide layer. In this case, the Al concentration at the surface of thealuminide coating is at least ≥15 wt pct. Formation of high Al concentration phases (FeAl3 andFe2Al5) during aluminizing should be avoided as they tend to embrittle the aluminide layer andreduce its oxidation resistance.

关键词： OO Figure Oxidation Resistance of the Aluminide Coating Formed on Carbon Steels

eco-toxicity and health risk assessment of polycyclic aromatic hydrocarbons in surface sediments of Burullus Lake in egypt

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China Geology 2024年第3期7卷 460-468页

作者： hanan e Osman Mohamed h e el-Morsy hazem T abd el-hamid Department of Biology Faculty of Applied ScienceUmm Al-Qura UniversityMecca 24382Saudi Arabia Deanship of Scientific Research Umm Al-Qura UniversityMakkah 24372Saudi Arabia National Institute of Oceanography and Fisheries(NIOF) Cairo 11865Egypt Botany and Microbiology Department Faculty of ScienceAl-Azhar UniversityCairo 11651Egypt

Polycyclic aromatic hydrocarbons(PAhs)are ubiquitous environmental contaminants of growing concern due to their potential ecological and human health *** study presents a comprehensive assessment of PAhs contamination in the surface sediments of Burullus Lake,a vital and second largest delta lake in *** aim was to evaluate the eco-toxicity and potential health risks associated with the presence of these *** seven sediment samples were collected from various drains in the southern part of Burullus *** extraction method was employed to extract PAhs(16PAhs)from the sediment ***,target compounds were located using *** results showed that samples contained PAhs levels ranging from 0.038×10^(-6)to 0.459×10^(-6),which is considered heavily polluted by the european standard for PAhs ***,there was no apparent source of PAhs in the elKhashah drain or the Brinbal Canal,as hPLC found none of the *** most prevalent compound in sediment samples along the study area was *** diagnostic indices in the present study indicated that the hydrocarbons in the region originated from pyrolytic and man-made sources along the drains of Burullus *** principal component analysis(PCA)and diagnostic ratios revealed that coal combustion and pyrolytic sources were responsible for the PAhs contamination in the surface *** non-carcinogenic risk(hI),which is the product of the hQs for the adult and child populations,respectively,was *** values under 1,therefore,demonstrated that they had no carcinogenic effects on human *** and MeQs in the sediments of Burullus Lake do not have a cancer-causing impact on *** the safety of nearby wildlife,aquatic life,and people,all activities that raise petroleum hydrocarbon levels in Burullus Lake must be adequately regulated and *** to the ecological risk assessment,there is little chance that PAhs will be found

关键词： Polycyclic aromatic hydrocarbons Diagnostic indices Toxicity Delta lake sediment Burullus Lake human health risk Aquatic ecosystem hPLC Coal combustion

Transport Properties of K_xV_2O_5·nh_2O Nanocrystalline Films

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Journal of Materials Science & Technology 2011年第10期27卷 865-872页

作者： A.A.Bahgat h.A.Mady A.S.abdel Moghny A.S.abd-Rabo Samia e.Negm Department of Physics Faculty of ScienceAl-Azhar University

Five different compositions of KxV2O5-nh2O （where prepared by the sol-gel process. electrical conductiv x=0.00, 0.0017, 0.0049, 0.0064 and 0.0091 mol） were ty and thermoelectric power were measured parallel to the substrate surface in the temperature range of 300-480 K. The electrical conductivity showed that all samples were semiconductors and that conductivity increased with increasing K content. The conductivity of the present system was primarily determined by hopping carrier mobility. The carrier density was evaluated as well. The conduction was confirmed to obey non-adiabatic small polaron hopping. The thermoelectric power or Seebeck effect, increased with increasing K ions content. The results obtained indicated that an n-type semiconducting behavior within the temperature range was investigated.

关键词： Vanadium pentoxide xerogel Nanocrystalline film electrical conductivity Small polaron hopping

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

Pack Aluminizing of Copper

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Journal of Materials Science & Technology 1997年第2期13卷 127-132页

作者： M.e.abd el-Azim h.M.Soliman (Metallurgy Dept., Atomic energy Authority Cairo, egypt) Metallurgy Dept. Atomic Energy Authority Cairo Egypt

Aluminizing of Cu by a pack cementation process was performed to improve its surface *** effect of variation of pack aluminizing temperature from 800 to 900℃ and aluminizing time from 1 to 6 h on the microstructure and the thickness of the aluminide coating of Cu was investigated. Pack aluminizing of Cu significantly improved the microhardness and the oxidation resistance. The microhardness was increased about seven times and the oxidation resistance,after 96 h exposure in air at 900℃, was extremely increased ten times by aluminizing Cu at 900℃ for 3 h.

关键词： VhN Pack Aluminizing of Copper

Performance of the Aluminide Coating of SomeLow Alloy Steels

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Journal of Materials Science & Technology 1997年第6期13卷 462-466页

作者： h.M.Soliman and M.e.abd e1-Azim(Metallurgy Dept., Atomic energy Authority, Cairo, egypt ) Metallurgy Dept. Atomic Energy Authority Cairo Egypt

Two low alloy steels 0.5Cr-0.5Mo-0.25V and h85 were pack-aluminized at 900°for 4 h by using Fe-Al powder mixture containing 48% Fe, 20.6% Al- 29.4% Al2O3 and 2% Nh4Cl by weight. The microhardness and oxidation resistance at 900℃ of the aluminide coatings were studied. It was found that pack-aluminizing improves the microhardness of the 0.5Cro.5Mo-0.25V steel while it reduces the microhardness of the h85 steel. Pack aluminizing highly improves the oxidation resistance after 20h exposure at 900℃ in air for the investigated steels.

关键词： Cr Performance of the Aluminide Coating of SomeLow Alloy Steels

Cylindrical Three-Dimensional Dust-Ion Acoustic Propagation in Plasmas

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Communications in Theoretical Physics 2018年第9期69卷 325-330页

作者： S.K.el-Labany e.K.el-Shewy h.N.abd el-Razek A.A.el-Rahman Theoretical Physics Group Faculty of Science Domietta University Department of Physics Taibah University Theoretical Physics Group Faculty of Science Mansoura University Department of Physics Faculty of Science Assiut University

Wave properties of solitons in an unmagnetized four-component dusty plasma system contains isothermal distributed electrons, mobile ions, and negative-positive dusty grains have been examined. To study DIA wave properties,a reductive perturbation (RP) analysis is used. By a reductive perturbation (RP) analysis under convenient coordinate transformation, the three dimension Kadomtsev-Petviashvili equation in cylindrical coordinates is obtained. The effects of dust grain charge on soliton pulse structures are studied. More specifically, solitary profile depending on the axial,radial, and polar angle coordinates with time is discussed. This investigation may be viable in plasmas of the earth’s mesosphere.

关键词： dust plasmas 3D-CKP equation dusty-ion acoustic solitary waves isothermal electrons