Publications

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Journal Article
Mahmoud, M. A., A. Poncheri, Y. Badr, and M. G. Abd El Waned, "Photocatalytic degradation of methyl red dye", South African Journal of Science, vol. 105, no. 7-8, pp. 299-303, 2009. AbstractWebsite
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Badr, Y., M. G. Abd El-Wahed, and M. A. Mahmoud, "Photocatalytic degradation of methyl red dye by silica nanoparticles", Journal of Hazardous Materials, vol. 154, no. 1-3, pp. 245-253, 2008. AbstractWebsite
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Ahmed, S. M., P. Szymanski, M. A. El-Sayed, Y. Badr, and L. M. El-Nadi, "The photoluminescence properties of undoped & Eu-doped ZnO thin films grown by RF sputtering on sapphire and silicon substrates", Applied Surface Science, vol. 359, pp. 356-363, 2015. AbstractWebsite
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Al-Shamiri, H. A. S., I. M. Azzouz, M. S. Shafik, and Y. A. Badr, "Photostablity and amplified spontaneous emission in dye-activated new organic-inorganic hybrid material", Journal of Sol-Gel Science and Technology, vol. 41, no. 1, pp. 65-69, 2007. AbstractWebsite
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Adel, D., A. A. M. Ward, N. Lotfy, A. Nassar, S. L. Abd-El-Messieh, M. A. Hafez, and Y. A. Badr, "PMMA nanocomposites based on laser fragmented Fe3O4nanoparticles", KGK Kautschuk Gummi Kunststoffe, vol. 70, no. 9, pp. 32-38, 2017. AbstractWebsite
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El-Kabbany, F., N. H. Taher, Y. Badr, and S. Taha, "POLYMORPHISM IN POTASSIUM SULPHATE.", Applied physics communications, vol. 6, no. 4, pp. 313-323, 1986. AbstractWebsite
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Anis, B., H. El Fllah, T. Ismail, W. M. Fathallah, A. S. G. Khalil, O. M. Hemeda, and Y. A. Badr, "Preparation, characterization, and thermal conductivity of polyvinyl-formaldehyde/MWCNTs foam: A low cost heat sink substrate", Journal of Materials Research and Technology, vol. 9, issue 3, pp. 2934–2945, 2020.
Badr, Y. A., M. A. Kereim, M. A. Yehia, O. O. Fouad, and A. Bahieldin, "Production of fertile transgenic wheat plants by laser micropuncture", Photochemical and Photobiological Sciences, vol. 4, no. 10, pp. 803-807, 2005. AbstractWebsite
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Gad, S., M. Fathy, Y. Badr, and A. E. - H. B. Kashyout, "Pulsed Laser Deposition of In0.1Ga0.9N Nanoshapes by Nd:YAG Technique ", Coatings, vol. 10,, 2020.
El‐Kabbany, F., Y. Badr, and G. Said, "Pyroelectric and dielectric behaviour of ammonium nitrate at the phase transition II–I", physica status solidi (a), vol. 63, no. 1, pp. 355-362, 1981. AbstractWebsite
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Badr, Y. A., K. M. Abd El-Kader, and R. M. Khafagy, "Raman spectroscopy study of CdS, PVA composite films", Journal of Applied Polymer Science, vol. 92, no. 3, pp. 1984-1992, 2004. AbstractWebsite
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Badr, Y. A. -kh., S. V. Karpov, and A. A. Shultin, "RAMAN SPECTRUM OF THE LATTICE VIBRATIONS OF RUBIDIUM AND CESIUM NITRATE CRYSTALS IN THE REGION OF THE LOW-TEMPERATURE ANOMALY OF THE DIELECTRIC CONSTANT.", Sov Phys Solid State, vol. 16, no. 8, pp. 1515-1516, 1975. AbstractWebsite
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Badr, I. H. A., M. Gouda, R. Abdel-Sattar, and H. E. M. Sayour, "Reduction of thrombogenicity of PVC-based sodium selective membrane electrodes using heparin-modified chitosan", Carbohydrate Polymers, vol. 99, pp. 783 - 790, 2014. AbstractWebsite

Abstract Heparin-modified chitosan (H-chitosan) membrane was utilized to enhance biocompatibility of sodium selective membrane electrode based on the highly thrombogenic polyvinyl chloride (PVC). Sodium ion sensing film was prepared using PVC, sodium ionophore-X, potassium tetrakis(chlorophenyl)-borate, and o-nitrophenyloctylether. The PVC-based sensing film was sandwiched to chitosan or H-chitosan to prevent platelet adhesion on the surface of PVC. Potentiometric response characteristics of PVC-chitosan and PVC-H-chitosan membrane electrodes were found to be comparable to that of a control \{PVC\} based sodium-selective electrode. This indicates that chitosan and H-chitosan layers do not alter the response behaviour of the PVC-based sensing film. Biocompatibility of H-chitosan was confirmed by in vitro platelet adhesion study. The platelet adhesion investigations indicated that H-chitosan film is less thrombogenic compared to PVC, which could result in enhancement of biocompatibility of sodium selective membrane electrodes based on PVC, while maintaining the overall electrochemical performance of the PVC-based sensing film.

Badr, I. H. A., M. Gouda, R. Abdel-Sattar, and H. E. M. Sayour, "Reduction of thrombogenicity of PVC-based sodium selective membrane electrodes using heparin-modified chitosan", Carbohydrate Polymers, vol. 99, pp. 783 - 790, 2014. AbstractWebsite

Abstract Heparin-modified chitosan (H-chitosan) membrane was utilized to enhance biocompatibility of sodium selective membrane electrode based on the highly thrombogenic polyvinyl chloride (PVC). Sodium ion sensing film was prepared using PVC, sodium ionophore-X, potassium tetrakis(chlorophenyl)-borate, and o-nitrophenyloctylether. The PVC-based sensing film was sandwiched to chitosan or H-chitosan to prevent platelet adhesion on the surface of PVC. Potentiometric response characteristics of PVC-chitosan and PVC-H-chitosan membrane electrodes were found to be comparable to that of a control \{PVC\} based sodium-selective electrode. This indicates that chitosan and H-chitosan layers do not alter the response behaviour of the PVC-based sensing film. Biocompatibility of H-chitosan was confirmed by in vitro platelet adhesion study. The platelet adhesion investigations indicated that H-chitosan film is less thrombogenic compared to PVC, which could result in enhancement of biocompatibility of sodium selective membrane electrodes based on PVC, while maintaining the overall electrochemical performance of the PVC-based sensing film.

Mohamed, T. A., A. M. Mustafa, W. M. Zoghaib, M. S. Afifi, R. S. Farag, and Y. Badr, "Reinvestigation of benzothiazoline-2-thione and 2-mercaptobenzothiazole tautomers: Conformational stability, barriers to internal rotation and DFT calculations", Journal of Molecular Structure: THEOCHEM, vol. 868, no. 1-3, pp. 27-36, 2008. AbstractWebsite
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Samsonov, A. V., M. M. Bogina, E. V. Bibikova, A. Y. Petrova, and A. A. Shchipansky, "The relationship between adakitic, calc-alkaline volcanic rocks and TTGs: implications for the tectonic setting of the Karelian greenstone belts, Baltic Shield", Lithos, vol. 79, no. 1–2, pp. 83 - 106, 2005. AbstractWebsite

Two types of coeval acid-intermediate rocks with different petrological, geochemical and isotopic features have been discovered among volcanic rocks and surrounding synkinematic tonalite–trondhjemite–granodiorite (TTG) plutons of Late Archaean greenstone belts in the Karelian granite–greenstone terrane. Type-1 rocks comprise trondhjemites and sub-volcanic, occasionally volcanic dacite–rhyolite rocks. They are characterized by high Sr, low Y and \{HREE\} contents, high Sr/Y ratios, and strongly fractionated \{REE\} patterns with no significant positive or negative Eu anomaly. Initial ɛNd is positive, indicating a generation from juvenile source with little or no contribution of ancient continental crust. Type 2 is represented by diorite–granodiorites and calc-alkaline basalt–andesite–dacite–rhyolite (BADR) series. As compared to type 1, these rocks differ by their lower Sr, higher Y and \{HREE\} contents, lower Sr/Y ratios and less fractionated \{HREE\} patterns with negative Eu anomalies. Initial ɛNd varies from negative to positive values, thus indicating a variable contribution of sialic crust. Geochemistry of the two magmatic series suggests their formation in a convergent plate margin setting. The type-1 rocks resemble Phanerozoic adakites, which represent slab-derived melts contaminated by overlying mantle wedge. The type-2 rocks resemble \{BADR\} series, which were derived from a mantle wedge metasomatized by slab-derived fluids and melts, with subsequent variable crustal contamination. The spatial distribution of these two types of magmatic series defines the asymmetry of the studied granite–greenstone structures, which presumably reflects the primary lateral zoning of island arc formed under specific thermal conditions in the Archaean mantle. Adakite melts upraised to the surface in the frontal part of the island arc, where mantle wedge was thin, showing no or little interaction with metasomatized mantle, and formed adakite-type plutonic and sub-volcanic rocks. At greater depths, adakitic melts and fluids interacted with the overlying mantle wedge and caused its partial melting with generation of calc-alkaline \{BADR\} volcanic rocks and diorite–granodiorite plutons in the rear part of the island arc. Our data suggest that greenstone belt volcano-plutonic arcs were initiated on different types of crust, which presumably determined the petrogenetic and isotope variations of the studied BADR- and adakite-type island-arc complexes.

Hegazy, S. F., Y. A. Badr, and S. S. A. Obayya, "Relative-phase and time-delay maps all over the emission cone of hyperentangled photon source", Optical Engineering, vol. 56, no. 2, 2017. AbstractWebsite
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Mabhaudhi, T., A. T. Modi, and Y. G. Beletse, "Response of taro (Colocasia esculenta L. Schott) landraces to varying water regimes under a rainshelter", Agricultural Water Management, vol. 121, pp. 102 - 112, 2013. AbstractWebsite

Taro [Colocasia esculenta (L.) Schott] is an underutilised crop in sub-Saharan Africa due to lack of agronomic research on it. There is no information describing water-use and drought tolerance of local taro landraces. Therefore, the objective of this study was to evaluate growth, yield and water-use of three South African landraces of taro under varying water regimes. Three taro landraces [Dumbe Lomfula (DL), KwaNgwanase (KW) and Umbumbulu (UM)] were planted in a rainshelter (14, October, 2010 and 8, September, 2011) at Roodeplaat, Pretoria, South Africa. Three levels of irrigation [30%, 60% and 100% crop water requirement (ETa)] were applied three times a week using drip irrigation. Emergence, plant height, leaf number, leaf area index (LAI) and stomatal conductance were measured in situ. Root length, fresh and dry mass were obtained by destructive sampling. Yield, yield components and water-use efficiency were determined at harvest. Taro landraces showed slow and uneven emergence. Stomatal conductance was respectively, 4% and 23% lower at 60% and 30% \{ETa\} relative to 100% ETa. Such a decline was clearer in the \{UM\} landrace, suggesting greater stomatal regulation in the \{UM\} landrace compared with \{KW\} and \{DL\} landraces. Plant growth parameters (plant height, leaf number and LAI) were shown to decrease by between 5% and 19% at 60% and 30% ETa, respectively, evapotranspiration relative to 100% ETa. The \{KW\} and \{DL\} landraces were shown to decrease the most while the \{UM\} landrace had moderate reductions in growth. Taro yield was 15% and 46% higher at optimum irrigation relative to 60% \{ETa\} and 30% ETa, respectively. Water-use efficiency was relatively unchanged (0.22–0.24 kg m−3) across varying water regimes. On average, the \{UM\} landrace had 113% higher \{WUE\} than the \{KW\} landrace. These findings can be used to differentiate the landraces on the basis of potential drought tolerance.

Taha, H. M., N. El-Bendary, A. E. Hassanien, Y. Badr, and V. Snasel, "Retinal feature-based registration schema", Communications in Computer and Information Science, vol. 252 CCIS, no. PART 2, pp. 26-36, 2011. AbstractWebsite
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Chehouri, A., R. Younes, A. Ilinca, and J. Perron, "Review of performance optimization techniques applied to wind turbines", Applied Energy, vol. 142, pp. 361 - 388, 2015. AbstractWebsite

Abstract This paper presents a review of the optimization techniques and strategies applied to wind turbine performance optimization. The topic is addressed by identifying the most significant objectives, targets and issues, as well as the optimization formulations, schemes and models available in the published literature. The current energy demand combined with depletion of fossil-fuel reserves and stricter environmental regulations have led to the development of alternative renewable energy solutions like wind energy. The current 2030 United States target is to have at least 20% of the \{US\} energy supply by onshore and offshore wind farms. To meet these demands, wind energy costs have to be able to compete with traditional fossil fuel sources. Hence, it is essential and vital that wind turbine designers and manufactures search the optimal solution that fits the objectives under a set of design constraints. Throughout the last 30 years, the objective function has evolved from the earlier maximized metric of the power coefficient to the maximization of the annual energy production. Common alternatives such as blade mass minimization and maximization of the rotor thrust and torque have been examined. However, the main objective has been focused on the minimization of the cost of energy in order for wind energy to become more competitive and economically attractive. The purpose of this paper is to review previous work that undertakes the performance optimization of horizontal wind turbines by highlighting the main aspects when tackling the wind turbine optimization problem such as: objective functions, design constraints, tools and models and optimization algorithms. In addition, in a conclusion of the review, a discussion and argument about the challenges, issues and future developments are identified.

Badr, Y., S. Abd El-wanees, and M. A. Mahmoud, "The ro-vibrational spectra of CO molecule resulting from the photolysis of acetone", Journal of Photochemistry and Photobiology A: Chemistry, vol. 167, no. 2-3, pp. 159-162, 2004. AbstractWebsite
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Selvaggi, R., L. Tarpani, A. Santuari, S. Giovagnoli, and L. Latterini, "Silica nanoparticles assisted photodegradation of acridine orange in aqueous suspensions", Applied Catalysis B: Environmental, vol. 168–169, pp. 363 - 369, 2015. AbstractWebsite

Abstract Silica nanostructured materials are often used as catalyst support but their catalytic role has not been deeply investigated yet. In the present study, the photocatalytic degradation of acridine orange zinc chloride double salt (AO) has been studied using silica nanoparticles (NPs) as catalysts. \{NPs\} of different size (55 and 146 nm) were prepared by a sol–gel procedure and their surface was modified with amino groups to investigate the role of the chemical groups linked to the silica surface on the dye degradation. The silica nanomaterials were fully characterized by use of transmission electron microscopy (TEM), zeta potential measurements and UV–vis spectrophotometric methods. The photodegradation experiments were carried out irradiating at 313 or 490 nm for 50 min the aqueous samples containing the dye and the silica \{NPs\} of 55 or 146 nm in diameter. The photocatalytic degradation of the dye was determined from the decrease of its fluorescence intensity. \{AO\} fluorescence intensity did not change when bare SiO2 beads were used as catalysts, whereas an efficient decoloration (up to 58%) was achieved with amino functionalized NPs, with a photodegradation rate constant value of 0.136 m−1. The data collected from the degradation experiments demonstrated that the functional groups on the silica surface have a fundamental role in the efficiency of the degradation processes.

Cerón, E. M., R. C. Mateos, and F. García-Río, "Síndrome de apneas-hipopneas del sueño y diabetes tipo 2. ¿Una relación de ida y vuelta?", Archivos de Bronconeumología, vol. 51, no. 3, pp. 128 - 139, 2015. AbstractWebsite

Resumen Diversos datos epidemiológicos muestran que el síndrome de apneas-hipopneas del sueño (SAHS) se relaciona independientemente con el desarrollo de resistencia a la insulina e intolerancia a la glucosa. Además, y pese a la existencia de notables limitaciones metodológicas, algunos estudios refieren una elevada prevalencia de \{SAHS\} en pacientes con diabetes tipo 2 (DM2). Un reciente metaanálisis muestra que el \{SAHS\} moderado-grave se asocia a un mayor riesgo de \{DM2\} (riesgo relativo = 1,63 [1,09-2,45]), en relación con la ausencia de apneas-hipopneas. La existencia de alteraciones comunes de diversas vías patogénicas le proporciona plausibilidad biológica a esta relación. La hipoxia intermitente y la fragmentación del sueño, originadas por la sucesión de episodios de apneas-hipopneas, inducen diversos trastornos intermedios, como la activación del sistema nervioso simpático, el estrés oxidativo, la inflamación sistémica, alteraciones en las hormonas reguladoras del apetito y activación del eje hipotálamo-hipófiso-suprarrenal, que favorecen el desarrollo de resistencia a la insulina, así como su progresión a intolerancia a la glucosa y, en última instancia, a DM2. La coexistencia del \{SAHS\} parece agravar la evolución de la DM2, al empeorar el control glucémico y potenciar el efecto de la aterosclerosis en el desarrollo de complicaciones macrovasculares. Además, el \{SAHS\} podría asociarse al desarrollo de complicaciones microvasculares, particularmente la retinopatía, nefropatía o neuropatía diabéticas. Aunque todavía escasos, algunos datos sugieren que la \{DM2\} también podría empeorar la evolución del SAHS, al favorecer la colapsabilidad de la vía aérea superior y potenciar la aparición de apneas-hipopneas centrales. Abstract Epidemiological data suggest that sleep apnea-hypopnea syndrome (SAHS) is independently associated with the development of insulin resistance and glucose intolerance. Moreover, despite significant methodological limitations, some studies report a high prevalence of \{SAHS\} in patients with type 2 diabetes mellitus (DM2). A recent meta-analysis shows that moderate-severe \{SAHS\} is associated with an increased risk of \{DM2\} (relative risk = 1.63 [1.09 to 2.45]), compared to the absence of apneas and hypopneas. Common alterations in various pathogenic pathways add biological plausibility to this relationship. Intermittent hypoxia and sleep fragmentation, caused by successive apnea-hypopnea episodes, induce several intermediate disorders, such as activation of the sympathetic nervous system, oxidative stress, systemic inflammation, alterations in appetite-regulating hormones and activation of the hypothalamic-pituitary-adrenal axis which, in turn, favor the development of insulin resistance, its progression to glucose intolerance and, ultimately, to DM2. Concomitant \{SAHS\} seems to increase \{DM2\} severity, since it worsens glycemic control and enhances the effects of atherosclerosis on the development of macrovascular complications. Furthermore, \{SAHS\} may be associated with the development of microvascular complications: retinopathy, nephropathy or diabetic neuropathy in particular. Data are still scant, but it seems that \{DM2\} may also worsen \{SAHS\} progression, by increasing the collapsibility of the upper airway and the development of central apneas and hypopneas.

Badr, Y., and M. A. Mahmoud, "Size-dependent spectroscopic, optical, and electrical properties of PbSe nanoparticles", Crystal Research and Technology, vol. 41, no. 7, pp. 658-663, 2006. AbstractWebsite
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Badr, Y., and M. A. Mahmoud, "Size-dependent surface-enhanced Raman scattering of sodium benzoate on Silver nanoparticles", Journal of Molecular Structure, vol. 749, no. 1-3, pp. 187-192, 2005. AbstractWebsite
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