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Harmonic Distortion Rate Analysis of H-Bridges Multilevel Inverter

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材料科学与工程（中英文B版） 2011年第3期1卷 308-315页

作者： Mohamed Nejib Ben nasr Khammassi Anis Kebir Faouzi Ben Ammar Unite de recherche SICISI ESSTT 5av. Taha Hussein BP 56 Bab Mnara-1008 Universite de Tunis Tunisia Unite de recherche. LSE INSAT Centre Urbain Nord BP 676 1080 Tunisia

Electronic Transport Study of ZnTe and ZnSe

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Materials Sciences and Applications 2011年第5期2卷 364-369页

作者： Siham Khedim nasr-Eddine Chabane Sari Boumediene Benyoucef Benyounes Bouazza 不详

The transport properties of electrons in ZnTe and ZnSe are of great interest because of their numerous technological applications. This paper investigates several calculation results of Monte Carlo device simulation. The average quantities directly accessible by the simulation are the drift velocity, the carriers’ energy and diffusion. The method we choosed to study the transport phenomena uses a three valley model (Γ, L, X) non-parabolic. The results have been obtained by applying the electric field in the direction . Finally we compared our results with those obtained previously.

关键词： Transport Properties Monte Carlo Method Three Valley Model Semiconductor Materials

Cascaded H-Bridges Asymmetrical 11-Levels Optimization

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材料科学与工程（中英文B版） 2011年第4期1卷 496-503页

作者： Mohamed Nejib Ben nasr Khammassi Anis Kebir Faouzi Ben Ammar Unite de Recherche SICISI ESSTT 5av. Taha Hussein BP 56 Bab Mnara-lO08 Universite de Tunis Tunisia Unitd de Recherche.＂ LSE INSA T Centre Urbain Nord BP 676 1080 Tunis

Efficient Fast Multiplication Free Integer Transformation for the 1-D DCT of the H.265 Standard

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Journal of Software Engineering and Applications 2010年第8期3卷 784-795页

作者： Mohamed nasr Haggag Mohamed El-Sharkawy Gamal Fahmy Maher Rizkalla German University at Cairo New Cairo City Cairo Egypt Egypt Japan University of Science and Technology Borg Al Arab Alexandria Egypt Electrical Engineering Dept. Assiut University Egypt

In this paper, efficient one-dimensional (1-D) fast integer transform algorithms of the DCT matrix for the H.265 stan-dard is proposed. Based on the symmetric property of the integer transform matrix and the matrix operations, which denote the row/column permutations and the matrix decompositions, along with using the dyadic symmetry modification on the standard matrix, the efficient fast 1-D integer transform algorithms are developed. Therefore, the computational complexities of the proposed fast integer transform are smaller than those of the direct method. In addition to computational complexity reduction one of the proposed algorithms provides transformation quality improvement, while the other provides more computational complexity reduction while maintaining almost the same transformation quality. With lower complexity and better transformation quality, the first proposed fast algorithm is suitable to accelerate the quality-demanding video coding computations. On the other hand, with the significant lower complexity, the second proposed fast algorithm is suitable to accelerate the video coding computations.

关键词： Fast Algorithm HDTV H.265 ICT Order-16 Transform Video Coding

Amplitude EEG Changes in Preterm Infants at NICU of Al-Zahraa University Hospital

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Open Journal of Pediatrics 2021年第3期11卷 450-459页

作者： Yomna Reda Zeinab Farag Oshaiba Eatemad Nabil Mansour Haidy Mahmoud nasr Al-Zahraa University Abbassya Egypt

Background: With increase in the incidence of preterm birth, quality of life in premature infants who suffer from perinatal brain injury has become a major concern. Amplitude electroencephalogram has the advantages of being simple bedside monitoring for assessment of brain function and follow up in preterm neonates. Aim of Study: To evaluate the aEEG changes in preterm infants and compare it to cranial ultrasound. Patients and Methods: This was a prospective observational study conducted at the NICU of Al Zahraa University Hospital for a period from May 2020 to May 2021. Our study was conducted on 60 preterm infants (26 - 36 w) in the first 7 days of life with exclusion of obvious congenital anomalies and hypoxic ischemic encephalopathy patients. Cranial ultrasound was performed on all the studied groups then aEEG recording was done for 4 hours. Results: The pattern of aEEG was discontinuous in patients with low gestational age and in infants small for gestational age. The pattern was also discontinuous in infants who had convulsions. Among our studied infants who had PROM, pre-eclampsia and experienced prolonged delivery, some infants had low voltage amplitude recording as well as infants with intraventricular hemorrhage grade III. Conclusion:

关键词： Preterm Convulsions Amplitude EEG

Unusual Catalytic Process Involving OH and NH Exchange

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International Journal of Organic Chemistry 2012年第1期2卷 64-70页

作者： Ramadan M. Ramadan Ahmad K. Abu Al-nasr Applied Chemistry Department Faculty of Applied Science Taibah University Almadinah Almunawrah Kingdom of Saudi Arabia

Interaction of some transition metals species with a Schiff base, 1, derived from 4,6-diacetylresorcinol and 2-amino- 5-methylphenol (1:2 mole ratio) yielded the two compounds 4-ethanimidoyl-6-[(1E)-N-(2-hydroxy-4-methylphenyl) ethanimidoyl]benzene-1,3-diol, 2, and 4,6-diacetyl-1,3-diaminobenzene, 4 via unusual catalytic process involving OH and NH exchange. All the compounds are characterized by elemental analysis, IR, mass and 1H NMR. The structure of the two compounds 2 and 4 are also determined by X-ray analysis. The crystal structure analysis revealed that the two compounds crystallized in the monoclinic space group P21/c with a Z value of 4.

关键词： Bicompartment Ligand Schiff Bases Diaminobenzene X-Ray Analysis

Analytical Study of a Heat Recovery/Desiccant Cooling System under Tunisian Climatic Conditions

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Analytical Study of a Heat Recovery/Desiccant Cooling System...

Effect of Egyptian propolis on cryptosporidiosis in immunosuppressed rats with special emphasis on oocysts shedding,leukogram,protein profile and ileum histopathology

作者： Seifennasr Sabek Kaouther Ben nasr Ridha Chouikh Amenallah Guizani the Centre des Recherches et des Technologies de l’Energie (CRTEn) the Ecole Nationale d’Architecture et d’Urbanisme the Institut Supérieur de Mathématiques Appliquées et d’ Informatique (ISMAI)

The solar potential energy in Tunisia can be used like a principal factor for the operation of new technologies of air *** could be carried out like approaches of simulation,analyzes experimental or both *** this paper,we present an analytical solution of heat and mass transfer processes in regenerator and air conditioning system(ACS) cores of a heat recovery/desiccant cooling system(HRDCS) under Tunisia weather *** programs were carried out to test the principal components of the HRDC *** results show that the coefficient of performance of system improves when we use the renewable energy for heating and *** study is significant and effective to prove the efficiency of such HRDC systems in this country.

关键词： Air conditioning liquid desiccant cooling system simulations Tunisian climatic conditions

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Asian Pacific Journal of Tropical Medicine 2017年第3期10卷 240-248页

作者： Hamdy Soufy Nadia M.El-Beih Soad M.nasr Tamer H.Abd El-Aziz Fathia A.M.Khalil Youssef F.Ahmed Hala A.A.Abou Zeina Department of Parasitology and Animal Diseases National Research Centre Department of Zoology Faculty of ScienceAin Shams University Department of Reproduction and Artificial Insemination National Research Centre

Objective:To investigate the activity of Egyptian propolis extracts(ethanol and water)on cryptosporidiosis in experimentally infected dexamethasone-immunosuppressed ***:A total of 180 male rats(190-220)g BWt were randomly divided into 9 equal groups(G1-G9).Groups of rats were kept as(G1):normal control,(G2-G9):immunosuppressed with dexamethasone and(G3-G9):infected with Cryptosporidium *** from(G4to G9)were given orally ethanol and water extract of propolis(at a dose of 50 mg/kg BWt)and nitazoxanide(standard anti-cryptosporidial drug at a dose of 100 mg/kg BWt)to infected rats with different *** pellets were collected from all groups to monitor oocysts shedding from the 2nd to the 15th day post *** the end of the experiment,blood was collected from all groups for determination of leukogram and serum *** specimens were also examined ***:The highest reduction of oocysts shedding in faecal samples was 88%in rats prophylactically treated with propolis ethanol extract at the 4th dpi,and in rats prophylactically treated with water extract of propolis,was91%at the 6th *** was a marked increase in neutrophils count and α_2-andβ-globulins levels in infected rats treated with both extracts,while a significant decrease was detected in lymphocytes compared to the infected non treated group.β-globulin level markedly increased in the rats administered *** changes were observed in the ileum of rats infected with ***:Egyptian propolis extracts have an activity on cryptosporidiosis in ***,propolis modulated the immunity in dexamethasone-immunosuppressed rats.

关键词： Cryptosporidiosis Propolis Rat model Leukogram Serum proteins Histopathology

The Influence of Polyurethane Foam on the Insulation Characteristics of Mortar Pastes

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Journal of Minerals and Materials Characterization and Engineering 2017年第2期5卷 49-61页

作者： Ahmed Adel Mahmoud Elsayed Abdel Ader nasr Ahmed Abdel Hamed Maamoun Department of Physics and Mathematics Faculty of Engineering Ain Shams University Cairo Egypt Department of Structural Engineering Ain Shams University Cairo Egypt

Rigid polyurethane foam is found virtually everywhere in our modern world and is used in sound and thermal insulation applications such as refrigerators, insulated buildings, thermosets. Organometallic compounds are used as polyurethane catalysts since they are very highly selective towards the isocyanate-polyol reaction. Also, amine catalysts are used to balance both the gelling reaction and the gas-forming or foaming reaction responsible for foam formation. In this work, the effect of a tin octoate catalyst on the mechanical properties and morphology of polyurethane foam were investigated. Also, the thermal conductivity and sound absorption coefficient for polyurethane foam mortar formulations were measured. The morphological properties of polyurethane foam were investigated using scanning electron microscope to determine the influence of varying the concentration of tin octoate. It was clear from the results that polyurethane foam has good thermal and sound insulation capabilities.

关键词： Polyurethane Foam Organometallic Catalyst Compressive Strength Thermal Conductivity Sound Absorption Coefficient