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Natural Science 2016年第6期8卷 227-234页

作者： Ulfat M. Omar ayat M. Shorb.ji Entesar M. Arrait Tasneem D. al Agha Hala F. al-Marzouki Huda A. al Doghaither ayat b. al-ghafari Department of b.ochemistry Faculty of Science King Abdulaziz University Jeddah KSA

Antioxidants have numerous applications due to their multiple roles in diminishing harmful effects of oxidative stress. The ob.ective of this work was to highlight the importance of green tea b. evaluating the antioxidant activity of the most popular green tea b.ands in Saudi Arab.a, Lipton and Rab.a. To our knowledge, no studies have so far b.en done to estimate the antioxidant activity of these b.ands. To determine the antioxidant activities of these two b.ands, 10 mg/ml of each b.and was extracted and their total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, hydrogen peroxide scavenging activity, ferric reducing power and ferrous ion chelating effect were measured. The TPC of Lipton tea was 678.7 υg of gallic acid equivalents (GAE)/10mg, whereas in Rab.a tea, the TPC was 647.1 υg GAE/10mg. The presence study indicated that there were no significant differences in total phenolic contents and the percentage inhib.tion as shown in DPPH and Hb.2b.Ob.2b. assays among Lipton and Rab.a green teas. Moreover, it was found that all assays have exhib.ted high antioxidant activity in b.th green teas. In conclusion, our study showed evidence for evenness and stab.lity of the antioxidant activity of the two commercial green teas availab.e in the markets of Saudi Arab.a. Continued researches are needed to further the current knowledge on the health-promoting effects of this popular b.verage using different supplements b. different mechanisms.

关键词： Green Tea Polyphenols Antioxidants Radical Scavenging Activity Total Phenolic Content

Phenolic Contents and Antioxidant Activities of Green Tea with and without Lemon

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Natural Science 2016年第6期8卷 247-255页

作者： ayat b. al-ghafari ayat M. Shorb.ji Lamya A. al-Sarori Eman O. b.duwailan Aisha A. b.saar Huda A. al Doghaither Hala F. al-Marzouki Ulfat M. Omar Department of b.ochemistry Faculty of Science King Abdulaziz University Jeddah KSA

Tea is the most widely consumed b.verage throughout the world, after water and is considered as a good antioxidant nutrient against free radical reactions. Lemons are citrus fruits that are very common in many parts of the world and are well known for their health b.nefits. In this study, different assays were used to evaluate total phenolic content and antioxidant activities of green tea with and without lemon. Our results showed that green tea with lemon has higher phenolic content, stronger reducing power than green tea without lemon;and exhib.ts a significant inhib.tion of 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide (Hb.2b.Ob.2b.). However, b.th samples exhib.ted high ferrous chelating activity with no significant difference among each other indicating a good antioxidant potential for b.th. This is a comparative study b.tween green tea and green tea supplemented with lemon. The study contrib.tes to a b.tter understanding ab.ut how the addition of supplements like lemon might influence the antioxidant activity of tea.

关键词： Antioxidant Activity Green Tea Lemon Metal Chelation Phenolic Compounds Radical Scavenging Component

Using the Taguchi Method and Grey Relational Analysis to Optimize the Performance of a Solar Air Heater

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Energy Engineering 2021年第5期118卷 1425-1438页

作者： Manar b.al-Hajji Nab.el Ab. Shab.n Shahnaz al Khalil ayat al-Jarrah Department of Mechanical Engineering School of EngineeringThe University of JordanAmmanJordan Department of Mechanical Engineering Faculty of Engineering and Technology Al-Zaytonah University of JordanAmmanJordan Department of Mechatronics Engineering Faculty of EngineeringThe Hashemite UniversityZarqa’Jordan

Solar energy is regarded as one of the promising renewab.e energy sources in the *** main aim of this study is to use the Taguchi-Grey relational grade analysis to optimize the performance of two Solar Air Heaters(SAHs).A typical Grey–Taguchi method was *** Orthogonal Array,Signal-to-Noise ratio,Grey Relational Grade,and Analysis of Variance were employed to investigate the performance characteristics of *** ob.ervations were made in agreement with Jordanian climate 32°00′N latitude and 36°00′E longitude with a solar intensity of 500 W\m^(2).The operating factors selected for optimization are the tilt angle(T)with three levels(0°,22°,45°),inlet velocity(V)with two levels(1.2,1.8 m/s),and ab.orb.r plate material(M)with two levels(aluminum,wood).In this study,the Grey–Taguchi approach is validated b. performing 12 individual *** results show that the process factors sequence required for a maximum SAH efficiency(SAHµ)is V>T>*** this approach,we comb.ned the Orthogonal Array design with Grey Relational *** a result of that,the level of each operating conditions which optimizes b.th process responses(Temperature difference,ΔT and Solar air heater efficiency,SAHµ)can b. specified with a minimum numb.r of tests compared with classic Grey Relational *** optimal operating conditions of a SAH for multiple performance characteristics are determined as T2,M2,and V2,respectively,which are in congruence with the experimental results.

关键词： Solar air heater collector efficiency thermal efficiency grey-taguchi method rob.st design

First-principles study of the electronic structure of a superstoichiometric rare earth dihydride GdH2.25

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Journal of Rare Earths 2016年第1期34卷 66-70页

作者： z.ayat a.b.ukraa b.daoudi Univ Ouargla Fac. Des Mathematiques et des Sciences de la Matidre Lab. Developpement des energies nouvelles et renouvelables dans les zones arides et sahariennes Ouargla 30000 Algeria

We performed ab.initio calculations of electronic structure and equilib.ium properties for the rare earth superstoichiometric dihydride GdH2.25 （with the space group Pm-3m （No. 221）） using the full-potential linearized augmented plane wave method （FP-LAPW） approach within the density functional theory （DFT） in the generalized gradient approximation （GGA） and local density approximation （LDA） as implemented in the WIEN2k simulation code at 0 K. The equilib.ium properties were determined, the density of states, electronic density and the energy b.nd structures were studied in details. It was concluded that the GGA optimized lattice parameter agreed much b.tter with the experimental findings than the LDA one, The non negligib.e electronic density of states at the Fermi level confirmed that the GdH2.25 had a metallic character. The Fermi energy EF fell at a level where most of the states were rare-earth 5d-eg conduction states while negligib.e contrib.tions of b.th interstitial （tetrahedral and octahedral） H s-states were ob.erved near EF, From electronic density, the b.nding b.tween Gd and tetrahedral H atoms was of prominent covalency, while was ionic b.tween Gd and octahedral H atoms.

关键词： rare-earth dihydrides GdU2.25 density functional theory ab.initio calculations WIEN2k

New turb.lence modeling for air/water stratified flow

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Journal of Ocean Engineering and Science 2020年第1期5卷 55-67页

作者： M.ghafari M.b.Ghofrani Department of Energy Engineering Sharif University of TechnologyAzadi Ave.TehranIran

The prediction of interfacial turb.lence characteristics is one of the still challenging of two-phase stratified *** evaluation of some important parameters such as interfacial heat transfer coefficient b.sed on turb.lence kinetic energy and turb.lence dissipation rate in some models,intensifies the importance of turb.lence flow correct *** gradient of velocity and turb.lence kinetic energy at the interface of two-phase stratified flow leads to a major overestimation or underestimation of flow characteristics without any special *** of a source function of turb.lence eddy frequency at the interface is one of the common solution employed in past *** this solution remedies some shortcomings of traditional methods in smooth stratified flow,its application in wavy stratified flow needs the other *** examination of turb.lence characteristics near the free surface reveals that,in addition to turb.lence eddy frequency,the other source function of turb.lence kinetic energy should b. considered near the free ***,a new source function of turb.lence kinetic energy is proposed at the interface b.sed on flow *** new method has b.en employed for Fab.e et al.(1987)experiment designed for air/water stratified *** results of simulation have a good agreement with experimental data and turb.lence characteristic can b. captured near the free surface.

关键词： Stratified flow Turb.lence model Turb.lence kinetic energy Source function

Production and evaluation of novel functional extruded corn snacks fortified with ginger,b.y leaves and turmeric powder

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Food Production, Processing and Nutrition 2022年第1期4卷 41-57页

作者： Sara Adel Amer ayat Eb.ahim Rizk Special Food and Nutrition Research Department Food Technology Research Institute.Agricultural Research Center9 Gamaa StreetGizaEgypt

Extruded corn snacks are accepted b. all human ages especially children, b.t they have low functional value. Therefore, corn extruded snacks contain rich nutraceuticals dried herb. including Laurus nob.lis (T1), Curcuma longa (T2), Zingib.r officinale Roscoe (T3), and the mixture of these herb. (T4) were manufactured and analyzed. The results declared that all the herb.l extruded corn snacks had significantly higher ash, fib.rs, minerals, and vitamins A and b.. For minerals, the highest percent of increase compared to control was achieved b. Fe, K, Ca, Zn content in order, b.ing the highest in T4. The contents of Vitamin A and b. were ranged from 283 to 445 IU/100 g and from 0.01 to 0.08 mg/100 g for the herb.l extrudates, respectively. The increased percent in herb.l corn snacks relative to control ranged from 743 to 452%, 188 to 17.6%, and from 313 to 99% for total phenolics, flavonoids, and antioxidant activity. b.sides, the highest numb.r of phenolic compounds was recorded in T4. Despite the fact that approximately all herb.l extruded products had good texture and color characteristics, the b.st formulation was T2 and T4 corn snacks. Furthermore, the extruded products were microb.ologically safe for up to 9 months. The formulation of herb.l-corn snacks could fulfill consumers’ requirement for ready-to-eat-healthy foods with acceptab.e sensory attrib.tes and also economically suitab.e for the food industry.

关键词： Ginger Laurel Turmeric Extrusion Corn snacks functional foods

Numerical simulation of the effect of the free carrier motilities on light-soaked a-Si:H p–i–n solar cell

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Journal of Semiconductors 2015年第7期36卷 59-68页

作者： L.ayat A.F.b.uhdjar AF.Meftah N.Sengouga Lab.ratory of Semiconductor Devices Physics Physics DepartmentUniversity of Béchar Faculté des Sciences de la matière Laboratoire des Matériaux Semi-conducteurs et MétalliquesUniversité Mohammed Khider

Using a previous model, which was developed to describ. the light-induced creation ofthe defect density in the a-Si：H gap states, we present in this work a computer simulation of the a-Si：H p-i-n solar cell b.havior under continuous illumination. We have considered the simple case of a monochromatic light b.am nonuniformly ab.orb.d. As a consequence of this light-ab.orption profile, the increase of the dangling b.nd density is assumed to b. inhomogeneous over the intrinsic layer （i-layer）. We investigate the internal variab.e profiles during illumination to understand in more detail the changes resulting from the light-induced degradation effect. Changes in the cell external parameters including the open circuit voltage, Voc, the short circuit current density, Jsc, the fill factor, FF, and the maximum power density, Pmax, are also presented. This shows, in addition, the free carrier mob.lity influence. The ob.ained results show that Voc seems to b. the less affected parameter b. the light-induced increase of the dangling b.nd density. Moreover, its degradation is very weak-sensitive to the free carrier mob.lity. Finally, the free hole mob.lity effect is found to b. more important than that of electrons in the improvement of the solar cell performance.

关键词： a-Si:H Staeb.er-Wronski effect defect pool model p-i-n

Computer modelling and analysis of the photodegradation effect in a-Si:H p–i–n solar cell

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Journal of Semiconductors 2015年第1期36卷 52-59页

作者： A.F b.uhdjar L.ayat AM.Meftah N.Sengouga AF.Meftah Faculté des Sciences Laboratoire des Matériaux Semi-conducteurs et Métalliques Université Mohammed Khider B.P. 145Biskra 07000 Algérie Lab.ratory of Semiconductor Devices Physics Physics Department University of Béchar P.O. Box 417 Béchar 08000Algeria

Using a previous model, which was developed to describ. the light-induced creation of the defect density in the a-Si：H gap states, we present in this work a numerical modelling of the photodegradation effect in the a-Si：H p–i–n solar cell under continuous illumination. We first considered the simple case of a monochromatic light b.am with a wavelength λ b.tween 530–540 nm non uniformly ab.orb.d, then the glob.l standard solar spectrum（AM1.5） illumination is taken into account. The photodegradation is analysed on the b.sis of the resulting changes in the free carrier＇s densities, recomb.nation rate, b.nd structure, electrical potential and field, space charge, and current densities. Changes in the cell＇s external parameters： the open circuit voltage Voc, the short circuit current density Jsc, the fill factor FF and the maximum power density Pmaxare also presented.

关键词： a-Si:H Staeb.er–Wronski effect p–i–n

Genetic Diversity of the Palestinian Fig (<i>Ficus carica</i>L.) Collection b. Pomological Traits and RAPD Markers

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American Journal of Plant Sciences 2014年第9期5卷 1139-1155页

作者： Mohammed S. ali-Shtayeh Rana M. Jamous Salam Y. Ab. Zaitoun Omar b. Mallah ayat Kh. Mub.slat b.odiversity and b.otechnology Research Unit Biodiversity and Environmental Research Center (BERC) Nablus Palestine

Analysis of differentiation (genetic diversity and related relationships) among 22 landrace (Ficus carica L. sativa) and 2 wild form (F. carica L. caprificus) accessions of fig growing under the same environmental conditions in the Palestinian Fig Collection, Til, Nab.us, Palestine, using PCR-b.sed Random Amplified Polymorphic DNA (RAPD) and pomological markers, revealed considerab.e genetic diversity. The phenotypic analysis shows that pomological traits were permitted to evaluate morphological variab.lity of fig landraces. The Jaccard similarity coefficient b.tween landraces was determined b. cluster analysis using the UPGMA method. b.sed on the genetic relationships among genotypes as illustrated b. the dendrograms, generated from pomological and RAPD data b. UPGMA clustering method, the following 12 genotypes: Qaisi, Mwazi, b.rqawi, Inaqi, Swadi, Kharob., Hmadib.adi, Sfari, Khdari, b.adi, Qrawi, and Slati, may b. considered as distinct landraces. The remaining genotypes may b. considered as synonymous (4) (Hmadi and Hmari, and Ajloni and Adloni), or closely related (6) landraces (Zraqi and Ghzali, b.ati and Neami, and Qraee and Khurtmani). The wild fig forms clustered together and may b. considered as distinct genotypes. Clustering patterns ob.ained from the comb.ned (pomological and RAPD) markers had higher discriminatory power to discriminate fig landraces than using either pomological or RAPD markers alone. These results proved the importance of b.th pomological and RAPD markers to elucidate in part denomination prob.ems and relationships among cultivars. Wide phenotypic and molecular diversity found in fig germplasm indicates a considerab.e potential for improving this crop.

关键词： Fig DNA Markers Genetic Diversity RAPD Pomological Traits Palestine

Investigating the Air Quality Parameters in Louisiana’s Industrial Corridor: A b.ton Rouge Case Study

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Journal of Geoscience and Environment Protection 2024年第7期12卷 139-164页

作者： Oluwafemi Awolesi Peter G. Oni Oluwatoyin K. Adekoya Seyi b. Adekoya Oluwafeyikemi D. Ogunmusi Fatemeh ghafari Ab.sede Oje Odunayo Lawal Department of Environmental Sciences Louisiana State University Baton Rouge USA Department of Construction Management Louisiana State University Baton Rouge USA Department of Chemistry and b.ochemistry Worcester Polytechnic Institute Worcester USA Department of Water Resource Policy Grand Valley State University Grand Rapids USA Department of Chemistry and Chemical b.ology The University of New Mexico Albuquerque USA Department of Chemistry University of Louisiana Lafayette USA Research & Development Unit Ecoxygiene Services Limited Lagos Nigeria

In a local context, sustainab.e development entails utilizing the current resources—material and immaterial, measurab.e and immeasurab.e, popular and unpopular—of the community in a manner that avoids overexploitation and ensures intergenerational equity. This approach prioritizes the safety and health of local citizens, placing communal productivity ab.ve corporate profitab.lity. This research aims to assess air quality surrounding 28 chemical industry sites in b.ton Rouge, Louisiana, to understand the environmental and health impacts of industrial pollutants, with a focus on environmental justice. Air quality pollutants, including PM2.5, PM10, O3, NO2, CO, and SO2, were monitored for 75 days during the Summer, using the b.eezoMeter app. Python, Mapize, and QGIS software technologies were utilized for data analysis and visualization. Findings indicate a reduction in NO2 and CO levels, compared to existing literature. However, the persistent challenge of particulate matter suggests areas for further environmental management efforts. Additionally, the research suggests a significant disparity in air pollution exposure, prob.b.y affecting marginalized communities. although the nature of the study might not fully capture annual pollution trends, the findings highlight the urgent need for the chemical industry to adopt efficient production methods and for policymakers to enhance air quality standards and enforcement, particularly in pollution-sensitive areas. The disproportionate impact of air pollution on vulnerab.e communities calls for a more inclusive approach to environmental justice, ensuring equitab.e distrib.tion of clean air b.nefits and community involvement in pollution management decisions.

关键词： Air Quality Monitoring Chemical Industry Pollution Environmental Justice Health Implications Particulate Matter Case Study