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Journal of Thermal Science 2021年第5期30卷 1625-1642页

作者： ismail BAKLOUTI Zied DRISS National School of Engineers of Monastir University of Monastir5019MonastirTunisia Laboratory of Electromechanical Systems(LASEM) National School of Engineers of SfaxUniversity of Sfax3038SfaxTunisia

The PVT-air solar system simultaneously generates electrical and thermal ***,increasing the cost-effectiveness of the system requires an appropriate choice of key parameters such as mass flow rate and air channel *** this paper,a PVT-air kit of a single module with a 30°slope was used to measure photovoltaic electricity and air heating power in the city of Sfax,***,a computer method was implemented using the ANSYS Fluent 17.0 software and the MATLAB program to analyse the properties of the airflow and to characterise PVT-air yields under different mass flow rates and *** the comparison of numerical and experimental data,the numerical method was validated with a good ***,we have found that increasing of the airflow rate improves the thermal efficiency with a slight change on electrical ***,the reduction in depth shows an improvement on thermal efficiency and a negligible effect on electrical ***,we have presented the thermal and electrical performance of PVT-air as a function of the key parameters with the Hottel-Whillier-Bliss formulation.

关键词： solar energy PVT-air thermal experimental numerical performance

The Role of Electrocardiogram DETERMINE Score in Prediction of Coronary Artery Disease Severity

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World Journal of Cardiovascular Diseases 2024年第9期14卷 567-580页

作者： ismail N. El-Sokkary Essam Ahmed Khalil Mohammed Wael Badawi Ibrahim K. Gamil Shousha Abdalla A. Elsebaey Mohamed Kamal Rehan Mahmoud Ibrahim Elshamy Yasser Ahmed Sadek Department of Cardiovascular & Thoracic Surgery Faculty of Medicine Al-Azhar University Cairo Egypt Department of Cardiology Al-Azhar University Cairo Egypt Department of Internal Medicine Beni-Sueif University Beni Suef Egypt Department of Radiology Al-Azhar University Cairo Egypt Department of Cardiology Helwan University Cairo Egypt

Background: A major cause of mortality and disability on a global scale is myocardial infarction (MI). These days, the most reliable way to detect and measure MI is via cardiovascular magnetic resonance imaging (CMR). Aims and Objectives: To evaluate the effectiveness of the Electrocardiogram DETERMINE Score in predicting the severity of coronary artery disease (CAD) in patients who have experienced an Acute Myocardial Infarction (AMI) & to assess improvements in left ventricular function at 6 months following coronary artery bypass grafting (CABG). Subjects and Methods: This Observational cohort study was done at the Cardiology and Radiology department and cardiac surgery department, Al-Azhar university hospitals and Helwan University hospital. The study involved 700 cases who patients diagnosed with Acute Myocardial Infarction and fulfilled specific criteria for selection. Result: There was highly statistically significant relation between Myocardial infarction size and ECG Marker Score as mean infarct size elevated When the number of ECG markers increased. There was a highly statistically significant relation between myocardial infarct segments, myocardial infarction size and improvement of cardiac function 6 months post-CABG. Conclusion: The study found that larger myocardial infarctions corresponded with higher DETERMINE Scores. It concluded that an ECG-based score better estimates infarct size than LVEF alone. Additionally, there was a significant statistical correlation between the size and segmentation of myocardial infarction and better cardiac function six months after CABG.

关键词： Electrocardiogram DETERMINE Score Coronary Artery Disease Outcome Acute Myocardial Infarction Coronary Artery Bypass Grafting

Availability of seismic vulnerability index(K_g) in the assessment of building damage in Van, Eastern Turkey

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Earthquake Engineering and Engineering Vibration 2020年第1期19卷 189-204页

作者： ismail Akkaya Van Yüzüncü Yil University Engineering FacultyDepartment of Geophysical Engineering

The seismic vulnerability index(Kg) is a parameter that depends on the dynamic properties of soil. With this parameter, it is possible to evaluate the vulnerability of a point-based site under strong ground motion. Since it is related to the natural vibration period and amplification factor, the parameter can be calculated for both soil and structure. In this study, HVSR microtremor measurements are recorded at more than 200 points in the Van region to generate a seismic vulnerability index map. After generating the map, it is determined that the hazard potential and seismic vulnerability index is high at the sites close to Van Lake and at the densely populated city center. Damage information of the buildings investigated after the 2011 Van earthquakes(Mw = 7.1) are placed on the seismic vulnerability index map and it is realized that there may be a correlation between the damage and the seismic vulnerability index. There is a high correlation, approximately 80 percent, between the damage rate map based on the damaged building data and the K_g values. In addition, vulnerability indexes of buildings are calculated and the effect of local soil conditions and building properties on the damage levels are determined. From the results of this study and the site observations after the 2011 Van earthquakes, it is found that structural damage is not only structure-dependent but is also related to the dynamic behavior of soil layers and local soil conditions.

关键词： seismic vulnerability index building damage HVSR soil-structure interaction

Observed failure modes of unreinforced masonry buildings during the 2015 Hindu Kush earthquake

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Earthquake Engineering and Engineering Vibration 2019年第2期18卷 301-314页

作者： Najif ismail Nouman Khattak Department of Civil and Environmental Engineering United Arab Emirates University

On 26 th October 2015, an Mw 7.5 earthquake struck northern Pakistan, with its epicenter located 45 km southwest of Jarm in the Hindu Kush region of Afghanistan. The earthquake resulted from reverse faulting at a depth of 210 km, resulting in 280 fatalities and substantial damage to some 109,123 buildings. Regional seismicity, characteristics of recorded strong motions, damage statistics, and building performance observations are presented. Earthquake damage was mostly constrained to seismic-deficient unreinforced masonry(URM) buildings. Typical failure modes included toppled minarets, partial or complete out of plane collapse of URM walls, diagonal shear cracking in piers, flexural cracking in spandrels, corner damage, pounding damage, and damage due to ground settlement. The majority of human loss resulted due to failure of URM walls and subsequent roof collapse. URM buildings located in rural hilly areas closer to the epicenter suffered more intense and frequent damage than urban URM buildings located farther away in larger cities.

关键词： Pakistan earthquake performance masonry buildings failure

Quasi-periodic variations of low energy cosmic rays

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Science China(Technological Sciences) 2016年第4期59卷 547-557页

作者： KUDELA Karel SABBAH ismail IEP SAS Kosice Slovakia Department of Natural Sciences College of Health Sciencesthe Public Authority for Applied Education and TrainingKuwait

Cosmic rays(CR)play an important role in space weather-related *** temporal variability,both of a quasi-periodic character as well as an irregular one,has been studied from ground-based direct measurements,as well as from cosmogenic nuclides,over a long *** attempt to describe the current knowledge of selected quasi-periodicities in CR flux in the energy range above the atmospheric threshold,from direct *** power spectrum density(PSD)of the CR time series as measured by neutron monitors(NMs)and by muon detectors has a rather complicated *** with the shape(slope)of the PSD,knowledge of the contribution of quasi-periodic variations(q-per)to the CR signal is of importance for the modulation,as well as for checking the links of CR to space weather,and/or to space climate *** rotation of the Earth and solar rotation cause two types of mechanisms behind the certain q-per observed in secondary CR on the Earth’s *** activity and solar magnetic field cyclicities contribute to the q-per signals in CR if studied over a longer *** complexity of the spatial structure of the interplanetary magnetic field(IMF)and its evolution within the heliosphere,in addition to the changes in the geomagnetic field,cause variability in contributions of the q-per in *** spectra are useful tools for checking the fine structure of q-per and their temporal *** a long time NMs and muon telescopes provide information about q-per in CR.

关键词： cosmic rays periodicities neutron monitors muon detectors

Nonlinear Intersubband Transitions in Square and Graded Quantum Wells Modulated by Intense Laser Field

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Chinese Physics Letters 2014年第12期31卷 95-98页

作者： Emine Ozturk ismail Sokmen Department of Physics Cumhuriyet University Sivas 58140 Turkey Department of Physics Dokuz Eylfil University Izmir 35160 Turkey

There has been increasing interest, both exper- imentally and theoretically, in the investigation of low-dimensional semiconductor heterostructures due to their intrinsic physical properties and technological applications in electronic and optoelectronic devices. The studies on quantum heterostructures have opened a new field in fundamental physics, and also offer a wide range of potential applications for optoelectronic devices. By varying the profile of a semiconductor quantum well （QW）, both the subband state energies and their wave functions change, and so do various physical properties depending on them.

关键词： Nonlinear Intersubband Square and Graded Quantum Intense Laser Field

Electronic Properties of p-Type δ-Doped GaAs Structure under Electric Field

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Chinese Physics Letters 2008年第4期25卷 1415-1418页

作者： Emine OZTURK ismail SOKMEN Department of Physics Cumhuriyet University 58140 SIVAS Turkey Department of Physics Dokuzeylul University IZMIR Turkey

We theoretically investigate the electronic properties of p-type δ-doped GaAs inserted into a quantum well under the electric field, at T = 0 K. We will investigate the influence of the electric field on the δ-doping concentration for a uniform distribution. The depth of confining potential, the density profile, the Fermi level, the subband energies and the subband populations calculate by solving the Schrodinger and Poisson equations self consistently. It is found that the changes of the electronic properties are quite sensitive to the applied electric field and the doping concentration. As different from single n-type δ-doped structure, we see a replace between the ground light-hole （lh1 ） subband and the first excited heavy-hole （hh2） subband whenever the external electric field reaches a critical value. We find the abrupt changing of the subband energies and the subband populations whenever the applied electric field reaches a certain value. Also, it is found that the heavy-hole subbands contain many more energy states than the light-hole ones, the population of the heavy-hole levels represent approximately 91% of all the carriers.

关键词： supernova explosion proto-neutron star shock wave

Advanced hydrogen storage of the Mg–Na–Al system:A review

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Journal of Magnesium and Alloys 2021年第4期9卷 1111-1123页

作者： N.A.Ali M.ismail Energy Storage Research Group Faculty of Ocean Engineering Technology and InformaticsUniversiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia

A solid-state storage system is the most practical option for hydrogen because it is more convenient and *** hydrides,especially MgH_(2),are the most promising materials that offer high gravimetric capacity and good ***,the practical application of MgH_(2) is restricted by slow sorption kinetics and high stability of thermodynamic *** storage performance of MgH_(2) was enhanced by introducing the Mg–Na–Al system that destabilises MgH_(2) with NaAlH_(4).The Mg–Na–Al system has superior performance compared to that of unary MgH_(2) and NaAlH_(4).To boost the performance of the Mg–Na–Al system,the ball milling method and the addition of a catalyst were *** Mg–Na–Al system resulted in a low onset decomposition temperature,superior cyclability and enhanced kinetics *** Al_(12)Mg_(17) and NaMgH_(3) that formed in situ during the dehydrogenation process modify the reaction pathway of the Mg–Na–Al system and alter the thermodynamic *** this paper,the overview of the recent progress in hydrogen storage of the Mg–Na–Al system is *** remaining challenges and future development of Mg–Na–Al system are also *** paper is the first review report on hydrogen storage properties of the Mg–Na–Al system.

关键词： Mg-Na-Al system MgH_(2) NaAlH_(4) Al_(12)Mg_(17) hydrogen storage

A Comparative Analysis on Surgical Outcomes and Complications of Endoscopic and Open Vein Harvesting Techniques

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Open Journal of Thoracic Surgery 2024年第2期14卷 29-39页

作者： Mohammed Fawzy Eltaweel ismail N. El-Sokkary Ahmed Alherazi Mohamed Wael Badawi Mohammed G. Abdellatif Bahaa A. Elkhonezy Ibrahim K. Gamil Haytham Mohamed Abd El Moaty Sarra Sadmi Mahmoud Khalil Department of Cardiothoracic Surgery Faculty of Medicine Menoufia University Shibin El Kom Egypt Department of Cardiovascular & Thoracic Surgery Faculty of Medicine Al-Azhar University Cairo Egypt Department of Cardiothoracic Surgery Faculty of Medicine Alexandria University Alexandria Egypt Faculty of Medicine University of Algiers Algiers Algeria Department of Cardiac Surgery Sabah Al-Ahmed Cardiac Center Al-Amiri Hospital Kuwait City Kuwait

Objective: The great saphenous vein (GSV) is commonly used as a conduit for grafting during CABG surgery, and open GSV harvesting (OVH), commonly used with long incision to expose the vein. However, endoscopic vein harvesting (EVH) is an alternative approach, utilizing specialized instruments and small incisions to harvest the vein. Methods: A retrospective analysis was conducted on a cohort of patients who underwent Coronary artery bypass graft (CABG) requiring great saphenous vein (GSV) harvesting which was done by EVH or OVH procedures. Demographic variables, including age and gender, were assessed for both groups. Intraoperative variables such as the number of grafts, cardiopulmonary bypass time, X clamp time, and type of procedure were analyzed. Postoperative variables, including infection and bleeding rates, were also evaluated. Results: The study included 30 patients each undergoing Coronary artery bypass graft (CABG) with need of great saphenous vein harvesting which was done by EVH and OVH. Demographic variables were well-matched between the two groups in terms of age, while a significant difference in gender distribution was observed. Obesity and smoking were more prevalent in the OVH group, and EVH was associated with a higher mean number of grafts compared to OVH. Conversion to an open technique occurred in a portion of the EVH cases, and infection rates did not significantly differ between the EVH and OVH groups. However, the incidence of postoperative bleeding was significantly higher in the EVH group. Conclusion: This study provides valuable insights into the demographic, intraoperative, and postoperative variables associated with EVH and OVH techniques. EVH demonstrated advantages in terms of reduced infection rates compared to OVH. However, the higher incidence of postoperative bleeding associated with EVH raises concerns about potential risks.

关键词： Endoscopic Vein Harvesting (EVH) Open Vein Harvesting (OVH) Coronary Artery Bypass Grafting (CABG) Great Saphenous Vein (GSV) Surgical Outcomes

Crystallization Conditions and Petrogenesis of the Paleoproterozoic Basement Rocks in Bangladesh:An Evaluation of Biotite and Coexisting Amphibole Mineral Chemistry

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Journal of Earth Science 2014年第1期25卷 87-97页

作者： ismail Hossain Toshiaki Tsunogae Department of Geology and Mining University of Rajshahi Faculty of Life and Environmental Sciences (Earth Evolution Sciences) University of Tsukuba Department of Geology University of JohannesburgAuckland Park 2006

The Paleoproterozoic （-1.73 Ga） basement rocks from Maddhapara, Bangladesh show a large range of chemical variations including diorite, quartz diorite, monzodiorite, quartz monzonite and granite. These are composed of varying proportions of quartz＋plagioclase＋K-feldspar＋biotite＋ hornblende±epidote＋titanite＋magnetite＋apatite and zircon. Amphibole and biotite, dominant ferro- magnesian minerals, have been analyzed with an electron microprobe. The biotite, Mg-dominant trioc- tahedral micas, is classified as phlogopitic nature. Relatively high Mg （1.33-1.53 pfu）, Mg^# （0.52-0.59） and low AIw （0.13-0.25 pfu） contents in the biotite reflect slightly fractionated magma, which might be a relative indicator for the origin of the parental magma. Biotite is also a very good sensor of oxidation state of the parental magma. Oxygen fugacity of the studied biotites estimate within the QFM and HM buffers and equilibrate at about -12.35 and -12.46, which exhibit the source materials were relatively higher oxidation state during crystallization and related to arc magmatism. Whereas, calcic amphi- boles, a parental member of arc-related igneous suite, display consistent oxygen fugacity values （-11.7 to -12.3）, low Al^# （0.16-0.21） with H2Omelt （5.6 wt.%-9.5 wt.%） suggest their reliability with the typical values of calc-alkaline magma crystallization. The oxygen fugacity of magma is related to its source material, which in turn depends on tectonic setting. Discrimination diagrams and chemical indices of both biotite and amphibole of dioritic rocks reveal calc-alkaline orogenic complexes; mostly I-type suite formed within subduction-related environments. Moreover, igneous micas are used as metal- logenic indicator. The biotites with coexisting amphibole compositions show an apparent calc-alkaline trend of differentiation. The study suggests that the trend of oxidized magmas is commonly associated with compressive tectonic and convergent plate boundaries.

关键词： oxygen fugacity biotite Paleoproterozoic basement rock Columbia supercontinent Bangladesh.