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Phytochemical Constituents and Allelopathic Effects of Some Medicinal Plants Extract on the Soil Algal Diversity

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Journal of Agricultural Science and Technology(A) 2013年第12期3卷 1000-1009页

作者： Mustafa ahmed fawzy AwatiefFahmey Hifney ahmed Abdel-Salam Issa Gamal Gareib Botany & Microbiology Department Faculty of Science Assiut University Assiut 71516 Egypt

Phytochemical constituents of the shoots and roots extract of chosen eight medicinal plants （Plantago major, Verbesina encelioides, Glinus lotoides, Helotropium supinum, Mentha microphylla, Euphorbia hirta, Juncus subulatus and Convolvulus arvensis） were estimated using standard qualitative analysis. The extract contained alkaloids, glycosides, saponins, phenols, tannins, f[avonoids and terpenoids in some medicinal plants while others contain some only of these phytochemical components. Allelopathic effect of the various concentrations of the extracts on the soil algal diversity was also investigated. Wollea saccata was the only algal species disappeared from all applied investigated plant extracts. Phormidium richardsii, Monoraphidium braunii, Eunotia verneris and Nitzschia bilobata were the highly sensitive algal species to all applied shoot and root extract from all tested plants, they disappeared from most of the studied plants. On the other hand, Phormidium animale and Chlorella neustonice were highly tolerant algal species to all applied extracts. Counts of Cyanophyceae, Chlorophyceae and Bacillariophyceae were decreased by addition of some investigated medicinal plants extracts such as Juncus subulatus, Convolvulus arvensis and Euphorbia hirta. So the authors can use these plants extracts in biocontrol of the nuisance of algal bloom or any other microorganisms. Also, these plants may be useful to recover eutrophic water which needs further investigation.

关键词： Allelopathy allelochemicals Plantago major Verbesina encelioides Glinus lotoides Phormidium richardsii,Monoraphidium braunii.

Polymeric biomaterial hydrogels. I. Behavior of some ionotropic cross-linked metal-alginate hydrogels especially copper-alginate membranes in some organic solvents and buffer solutions

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Advances in Bioscience and Biotechnology 2012年第7期3卷 845-854页

作者： Refat Hassan Fahd Tirkistani Ishaq Zaafarany ahmed fawzy Mohamed Khairy Sayed Iqbal Chemistry Department Faculty of Applied Sciences Umm Al-Qura University Makkah KSA Chemistry Department Faculty of Science Assiut University Assiut Egypt Chemistry Department Faculty of Science Benha University Benha Egypt Chemistry Department Saifia College of Science and Education Bhopal India

The change in rheological and mechanical properties for some ionotropic cross-linked metal-alginate hydrogel complexes in particularly copper-alginate membranes in the presence of some organic solvents (benzene, toluene, xylene, carbon tetrachloride, ace-tone, chloroform, dichloroethane, isobutyl alcohol and ethyl alcohol) or buffer solutions (acetates, borates and universal buffers) have been investigated. The experimental results showed a remarkable tendency of the studied hydrogels for shrinking in polar solvents, whereas no influence was observed for the hydrogels in non-polar solvents. On the other hand, the gels were found to swell or shrink in the buffer solutions depending on the pH of the buffer used. The swelling extent for hydrogel spheres was found to decrease in the order Cu > Ba ≈ Ca > Zn > Pb-alginates in universal buffers of pH = 5.33. The factors affected this behavior have been examined and discussed.

关键词： Biomaterials Hydrogels Swelling Shrinking Metal-Alginates Biocatalysts

Performance Analysis on a Dual External Cavity Tunable Laser ECTL Source

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Journal of Electromagnetic Analysis and Applications 2015年第4期7卷 134-139页

作者： ahmed fawzy Osama M. El-Ghandour Hesham F. A. Hamed Department of Electrical Engineering Minia University Minia Egypt Department of Electronics Communications and Computer Engineering Helwan University Cairo Egypt

This paper presents the diffraction effects on the performance of a dual external cavity tunable laser source, whose external cavities are constructed by micro electro mechanical systems (MEMS). One of the main problems in these structures is the optical diffraction as the emitting surface of the laser diode is usually quite limited in the transverse directions. The emitted beam diffracts rapidly in the air and only a small amount of light is coupled back to the source that usually limits the tuning range of the source. Device characteristics such as tuning range, wavelength shift and sensitivity are evaluated. New expression is used and multiple reflections inside external cavities are considered. The simulation results have shown that single external cavity has limited tuning range. It is shown that multiple reflections have significant effect in our model. To get a better engineering for the dual ECTL dimensions, diffraction effects must be taken into account.

关键词： External Cavity Laser Tunable Laser MEMS Optical Diffraction

A Comparative Kinetic Study on the Efficacious Permanganate Oxidation of Fluorenes in Perchloric and Sulfuric Acid Media

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Open Journal of Physical Chemistry 2017年第2期7卷 35-49页

作者： Rabab S. Jassas ahmed fawzy Rami J. Obied Mohammed A. S. Abourehab Saleh A. ahmed Chemistry Department Faculty of Applied Science Umm Al-Qura University Makkah Saudi Arabia Chemistry Department Faculty of Science Assiut University Assiut Egypt Department of Pharmaceutics Faculty of Pharmacy Umm Al-Qura University Makkah Saudi Arabia Department of Pharmaceutics and Industrial Pharmacy Faculty of Pharmacy Minia University Minia Egypt

Oxidation kinetics of fluorene (Fl) and its halogenated derivatives, namely, 2,7-dichlorofluorene (Fl-Cl), 2,7-dibromofluorene (Fl-Br) and 2,7-diiodofluorene (Fl-I), by permanganate ion in both perchloric and sulfuric acid media have been investigated using conventional spectrophotometric technique. In both acidic media, the reactions manifested first order kineticsin [permanganate] and less than unit order each in [reductants] and [acid]. Increasing ionic strength had no effect on the oxidation rates. Oxidation rates of fluorenes in perchloric acid were higher than those in sulfuric acid and the order of the oxidation rates was: Fl > Fl-I > Fl-Br > Fl-Cl. Final oxidation products were identified by GC/MS and FT-IR analyses in all cases as 9H-fluorenone derivatives. Reaction constants as well as activation parameters of the second order rate constants were also evaluated.

关键词： Oxidation Kinetics Mechanism Fluorenes Permanganate

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深度学习计算机视觉实战

深度学习计算机视觉实战

Supersymmetric hybrid inflation in light of CMB experiments and swampland conjectures

作者： (埃及)艾哈迈德·法齐·迦得(ahmed fawzy Gad)

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Chinese Physics C 2025年第1期49卷 114-126页

作者： Waqas ahmed Shabbar Raza Center for Fundamental Physics and School of Mathematics and Physics Hubei Polytechnic UniversityHuangshi 435003China Department of Physics Federal Urdu University of ArtsScience and TechnologyKarachi 75300Pakistan

In this study,we revisit supersymmetric(SUSY)hybrid inflation within the context of considering the latest Cosmic Microwave Background(CMB)observations and swampland *** demonstrate that SUSY hybrid inflation remains consistent with Planck 2018 data when radiative,soft mass,and supergravity(SUGRA)corrections are applied to the scalar *** is commonly perceived that SUSY hybrid inflation with a minimal Kahler potential results in a gauge symmetry breaking scale M of O(10^(15))GeV,leading to issues with the proton decay *** our analysis,we introduce a novel parameter space that alleviates the proton decay issue by achieving M~10^(16) GeV with M_(S)^(2)*** scenario necessitates a soft SUSY breaking scale|M_(S)|■10^(6) ***,we find that the tensor-to-scalar ratio r spans from 10^(-16) to 10^(-6),indicating a very small *** small ratio allows the modified swampland criteria to hold,although satisfying the trans-Planckian censorship conjecture(TCC)remains *** address this,we also explo non-minimal Kahler *** fixing the spectral index at n_(S)=0.9665,consistent with the central value of Planck 2018 data,and setting M=2×10^(16)GeV,we present our *** show that the canonical measure of primordial gravitational waves,r,for M_(S)=1 TeV,m_(3/2)=1 TeV,and k_(S)<0 for N=1 and N=2,ranges from 10^(-5) to 0.01,rendering it detectable by Planck and upcoming experiments such as LiteBIRD,Simons Observatory,PRISM,PIXIE,CORE,CMB-S4,and ***,we outline the parametric space and provide benchmark points for the non-minimal case to ensure compatibility with both the modified swampland conjecture and TCC.

关键词： suppersymmetry hybrid inflation swampland conjectures

Generalized uncertainty principle from the regularized self-energy

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Communications in Theoretical Physics 2025年第1期77卷 92-100页

作者： Kimet Jusufi ahmed Farag Ali Physics Department State University of TetovoIlinden Street nn1200TetovoNorth Macedonia Essex County College 303 University AveNewarkNJ 07102United States America Department of Physics Faculty of ScienceBenha UniversityBenha13518Egypt

We use the Schrödinger–Newton equation to calculate the regularized self-energy of a particle using a regular self-gravitational and electrostatic potential derived in string *** particle mass M is no longer concentrated into a point but is diluted and described by a quantum-corrected smeared energy density resulting in corrections to the energy of the particle,which is interpreted as a regularized *** extend our results and find corrections to the relativistic particles using the Klein–Gordon,Proca and Dirac *** important finding is that we extract a form of the generalized uncertainty principle(GUP)from the corrected *** form of the GUP is shown to depend on the nature of particles;namely,for bosons(spin 0 and spin 1)we obtain a quadratic form of the GUP,while for fermions(spin 1/2)we obtain a linear *** correlation we find between spin and GUP may offer insights for investigating quantum gravity.

关键词： generalized uncertainty principle T-duality regularized self-energy

Nanosecond pulse and dual-wavelength Q-switched 1.5 μm fiber laser using MAX phase Cr_(2)TiAlC_(2) saturable absorber

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Optoelectronics Letters 2025年第1期21卷 7-12页

作者： ahmed Shakir AL-HITI Hiba HASSAN Department of Electrical Engineering Faculty of EngineeringUniversity of AnbarAnbar 31001Iraq Department of Laser and Optoelectronics Engineering University of Technology-IraqBaghdadIraq

We demonstrated a new type of MAX phase material,chromium titanium aluminum carbide(Cr_(2)TiAlC_(2)) polymer film,to generate a passively Q-switched erbium-doped fiber laser(EDFL).The film thickness was measured to be around 45 μm,which was fabricated using the embedding method with polyvinyl alcohol(PVA) polymer as *** saturable absorber(SA) film demonstrates a dual-wavelength passively Q-switched EDFL which operates at 1 531 nm and 1 560.19 nm,*** Q-switching pulse duration could be varied from 2.46 μs to 770 ns,while the repetition rate varied from 92.76 kHz to 106.6 kHz with an increasing input pumping range from 154 mW to 300 *** maximum output power and pulse energy of 15.05 mW and 141.18 nJ were obtained at the maximum input power of 300 mW,respectively.

关键词： switched pulse fiber

Role of Right Ventricular-Pulmonary Arterial Coupling Measured by Echocardiography in Predicting Right Ventricular Dysfunction after Cardiac Surgery

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World Journal of Cardiovascular Surgery 2025年第1期15卷 1-11页

作者： Ismail Nasr El-Sokkary Esam ahmed Khalil Mohammed fawzy Eltaweel ahmed Alherazi Mohammed Samy Bahaa Abdelgawad Elkhonezy Mohamed El Sayed Moussa Mohamed ahmed Mosaad Zaki Ibrahim Abdel Fattah Yassin Mohamed Kamal Rehan Department of Cardiothoracic Surgery Faculty of Medicine Al-Azhar University Cairo Egypt Department of Cardiology Al-Azhar University Faculty of Medicine Cairo Egypt Department of Cardiothoracic Surgery Faculty of Medicine Menoufia University Shibin El Kom Egypt Department of Cardiothoracic Surgery Faculty of Medicine Alexandria University Alexandria Egypt Department of Internal Medicine Faculty of Medicine Beni Suef University Cairo Egypt

Background: The tricuspid annular plane systolic excursion (TAPSE) and pulmonary artery systolic pressure (PASP) is an indirect estimate of right ventricular-pulmonary arterial (RV-PA) coupling that has been shown to correlate with invasive measures. We aimed to assess the ability of the tricuspid annular plane systolic excursion/pulmonary systolic pressure ratio (TAPSE/PASP) as a measure for RV-PA coupling to predict the development of RV dysfunction after cardiac surgery. Methods: This prospective study was conducted on 100 patients with ischemic heart disease and undergoing cardiac surgery (coronary artery bypass graft (CABG)) with normal preoperative right ventricular function, classified according to RV function outcomes into 2 groups: Normal RV group (65 patients) and RV dysfunction group (35 patients). All cases underwent per and postoperative transthoracic echocardiography. Results: By using receiver operating characteristic curve analysis, pre-operative TAPSE/PASP ratio could significantly predict the RV dysfunction (P 0.58, with AUC of 94%, 88.6% sensitivity, and 89.2% specificity. Post-operative TAPSE/PASP Ratio could significantly predict the RV dysfunction (P 0.39, with AUC of 84%, 100% sensitivity, and 76.9% specificity. Pre-operative TAPSE/PASP ratio could significantly predict mortality (P Conclusion: The TAPSE/PASP ratio is an excellent tool for CABG patients for its ability to detect and predict the development of RV dysfunction after cardiac surgery, along with the prediction of mortality in post-operative CABG patients.

关键词： Right Ventricular Pulmonary Arterial Coupling Echocardiography Cardiac Surgery