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Entropy analysis in electrical magnetohydrodynamic(MHD) flow of nanofluid with effects of thermal radiation,viscous dissipation,and chemical reaction

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Theoretical & Applied Mechanics Letters 2017年第4期7卷 235-242页

作者： Yahaya Shagaiya Daniel Zainal Abdul Aziz Zuhaila Ismail faisal salah UTM Centre for Industrial and Applied Mathematics Universiti Teknologi Malaysia Department of Mathematics Faculty of Science University of Kordofan

The unsteady mixed convection flow of electrical conducting nanofluid and heat transfer due to a permeable linear stretching sheet with the combined effects of an electric field, magnetic field, thermal radiation, viscous dissipation, and chemical reaction have been investigated. A similarity transformation is used to transform the constitutive equations into a system of nonlinear ordinary differential *** resultant system of equations is then solved numerically using implicit finite difference *** velocity, temperature, concentration, entropy generation, and Bejan number are obtained with the dependence of different emerging parameters examined. It is noticed that the velocity is more sensible with high values of electric field and diminished with a magnetic field. The radiative heat transfer and viscous dissipation enhance the heat conduction in the system. Moreover, the impact of mixed convection parameter and Buoyancy ratio parameter on Bejan number profile has reverse effects. A chemical reaction reduced the nanoparticle concentration for higher values.

关键词： Entropy generation MHD nanofluid Thermal radiation Bejan number Chemical reaction Viscous dissipation

An End-to-End Transformer-Based Automatic Speech Recognition for Qur’an Reciters

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Computers, Materials & Continua 2023年第2期74卷 3471-3487页

作者： Mohammed Hadwan Hamzah A.Alsayadi salah AL-Hagree Department of Information Technology College of ComputerQassim UniversityBuraydah51452Saudi Arabia Department of Computer Science College of Applied SciencesTaiz UniversityTaiz6803Yemen Computer Science Department Faculty of Computer and Information SciencesAin Shams UniversityCairo11566Egypt Computer Science Department Faculty of SciencesIbb UniversityYemen Department of Computer Sciences&Information Ibb UniversityYemen

The attention-based encoder-decoder technique,known as the trans-former,is used to enhance the performance of end-to-end automatic speech recognition(ASR).This research focuses on applying ASR end-toend transformer-based models for the Arabic language,as the researchers’community pays little attention to *** Muslims Holy Qur’an book is written using Arabic diacritized *** this paper,an end-to-end transformer model to building a robust Qur’an *** is *** acoustic model was built using the transformer-based model as deep learning by the PyTorch framework.A multi-head attention mechanism is utilized to represent the encoder and decoder in the acoustic *** filter bank is used for feature *** build a language model(LM),the Recurrent Neural Network(RNN)and Long short-term memory(LSTM)were used to train an n-gram word-based *** a part of this research,a new dataset of Qur’an verses and their associated transcripts were collected and processed for training and evaluating the proposed model,consisting of 10 h *** recitations performed by 60 *** experimental results showed that the proposed end-to-end transformer-based model achieved a significant low character error rate(CER)of 1.98%and a word error rate(WER)of 6.16%.We have achieved state-of-the-art end-to-end transformer-based recognition for Qur’an reciters.

关键词： Attention-based encoder-decoder recurrent neural network long short-term memory qur’an reciters recognition diacritized arabic text

Can lanthanum doping enhance catalytic performance of silver in direct propylene epoxidation over NaMoAg/SiO_2?

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Journal of Rare Earths 2019年第5期37卷 500-507页

作者： Hany M.Abdel Dayem Shar S.Al-Shihry salah A.Hassan Chemistry Department Faculty of Science Ain Shams University Chemistry Department College of Science King Faisal University

In the attempt to reduce surface free energy of silica to improve interaction of silica with silver, silica was doped by different amounts of low surface energy lanthanum, La_2O_3, through impregnation. The doped and undoped silica were used as supports for preparation of Na/Ag/Mo/La_2O_3-SiO_2 catalysts. Catalytic performances of the catalysts were evaluated in direct epoxidation of propylene(DPO) using molecular oxygen under atmospheric pressure and without adding hydrogen. Adding 5 wt%La to the Na/Ag/Mo/SiO_2 catalyst improves both the catalysts electivity in DPO and its stability over 20h of *** characterization results show that La_2O_3 species interact strongly with silver particles on the silica surface which result in significant improvement in the dispersion profile of silver and marked decrease in the size of silver nanoparticles(AgNPs). The estimated mean diameter of AgNPs is ca. 4.0 nm in Na/Ag/Mo/5 wt%La_2O_3-SiO_2, which is smaller than that(53.9 nm) found in Na/Ag/SiO_2. The presence of subnanometer AgNPs on Ag/La_2O_3-SiO_2 prior addition of MoO_3 and NaCl to the sample can enhance the mutual electronic synergism between Ag, MoO_3 and Na for selective production of propylene oxide.

关键词： Direct epoxidation Propylene Gas phase Silver Subnanometer Lanthanum

Rare earth oxides doped NiO/γ-Al_2O_3 catalyst for oxidative dehydrogenation of cyclohexane

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Journal of Rare Earths 2015年第6期33卷 611-618页

作者： Hany M.AbdelD ayem M.Faiz Hesham S.Abdel-Samad salah A.Hassan Center of Research Excellence in Petroleum Refining & Petrochemicals (CoR E-PRP) King Fahd University of Petroleum & Minerals Chemistry Department College of Science King Faisal University Chemistry Department Faculty of Science Ain Shams University Surface Science Laboratory Physics Department King Fahd University of Petroleum &Minerals Department of Basic Sciences and Technology Community College Taibah University

The effect of rare earth oxides （RE=Ce, La, Gd, and Dy） doping of alumina support in NiO/7-A1203 system was investi- gated on its catalytic performance in oxidative dehydrogenation （ODH） of cyclohexane. The physicochemical properties of various samples were followed up through N2 physisorption, temperature programmed reduction （H2-TPR）, X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS） and potentiometric acid-base titration techniques. In the parent NiO/y-A1203 catalyst, Ni species were found to be strongly interacted with alumina surface. Addition of rare earth dopants to ）＇-A1203 in the catalyst system affected the nickel-alumina interaction and resulted in significant modifications in the catalytic performances in the ODH reaction. The results re- vealed the beneficial role of both La203 and Gd2Os doping in enhancing the ODH catalytic activity and selectivity to cyclohexene. H2-TPR and XPS results indicated that majority of Ni species in NiO/La203 modified T-A1203 were more weakly interacted with La203 and alumina whereas both NiO like species and nickel aluminate were present on the surface. Doping with cerium or dyspro- sium increased the nickel-support interaction and led to a decrease in surface nickel concentration. In case of doping with Ce, surface concentration of cerium oxide was higher than those of the other RE oxides; the doped catalyst reached its steady state activity faster than the other catalysts. The acid-base results suggested that RE metals were interacted most likely with acidic surface hydroxyl groups. The degree of nickel-alumina interaction decreased in the following order： LaAI〉GdAI〉CeAI〉DyA1.

关键词： nickel oxide rare-earth oxides doping Ni-A1203 interaction surface acidity oxidative dehydrogenation cyclohexane rare earths

Cutaneous leishmaniasis in Al Hassa, Saudi Arabia: Epidemiological trends from 2000 to 2010

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Asian Pacific Journal of Tropical Medicine 2013年第8期6卷 667-672页

作者： Tarek Tawfik Amin Hamdan Ibrahim Al-Mohammed Feroze Kaliyadan Balghonaim salah Mohammed King faisal University Cairo University Vector Control Unit Preventive Medicine Department Local Health Directorate Al Hofuf Ministry of Health

Objective: To study epidemiological trends related to cutaneous leishmaniasis (CL) in Al Hassa, an endemic area in Saudi Arabia. Methods: This retrospective study included the spatial/ temporal analysis of the reported cases of CL using the available surveillance database for the disease at the regional Vector Control Unit, from 2000 to 2010. Results: The incidence of CL was declining at a stable rate especially during the last 3 years of the study (2008-2010). An interesting finding was the percentage of expatriates affected was increasing over the last 10 years compared to that of the Saudis. Conclusions: A definite declining trend in the incidence of CL was observed in Al Hassa. Further studies are warranted to assess whether special public health measures are needed for better control of CL in expatriate populations in Saudi Arabia.

关键词： Cutaneous leishmaniasis Epidemiology Saudi Arabia

Microbial Loads and Physicochemical Characteristics of Fruits from Four Saudi Date Palm Tree Cultivars: Conformity with Applicable Date Standards

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Food and Nutrition Sciences 2014年第4期5卷 316-327页

作者： salah M. Aleid Bakri H. Hassan salah A. Almaiman Safar H. Al-Kahtani Sobhy M. Ismail College of Food and Agriculture Sciences King Saud University Riyadh Saudi Arabia Date Palm Research Center of Excellence King Faisal University Alahsa Saudi Arabia Department of Food Science and Nutrition King Saud University Riyadh Saudi Arabia.

The conformity of Saudi dates cultivars to date standards has not been studied extensively. In this study, microbial loads and physicochemical characteristics of four Saudi date cultivars (Sukkary, Khalas, Sugai and Anbara) were determined. Anbara cultivar had significantly higher mould and yeast counts than recommended under Saudi technical regulation and standards for packaged whole dates. Moisture content and insect damage for all studied cultivars fell within Codex standards. Single fruit weight for pitted and unpitted dates was higher than recommended under international standards. Date cultivar had a significant effect on fruit color thus fruit color should be included in Saudi technical regulation and standards for date grading.

关键词： Saudi Dates Standards Microbial Load Physicochemical Characteristics

Nutritional Quality of Biscuit Supplemented with Wheat Bran and Date Palm Fruits (<i>Phoenix dactylifera</i>L.)

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Food and Nutrition Sciences 2012年第3期3卷 322-328页

作者： Gamal A. El-Sharnouby salah M. Aleid Mutlaq M. Al-Otaibi Date Palm Research Centre of Excellence King Faisal University Al-Ahsa Saudi Arabia. Department of Food and Nutrition Sciences College of Agricultural and Food Sciences King Faisal University Al-Ahsa Saudi Arabia

Fruits of date palm (Phoenix dactylifera L.) are consumed throughout the world and are a vital component of the diet in most Arabian countries. The effect of partial replacement of wheat flour with a 1:1 mixture of wheat bran and date palm fruit powder on rheological properties of the biscuit dough was studied. Levels of mixture used were 10%, 20%, 30% and 40%. Dough rheology (farinograph, extensograph properties) and biscuit quality (physical properties, colour, sensory evaluation) were assessed. Results obtained indicated that water absorption gradually increased by increasing the levels of wheat bran: palm date powder, meanwhile mixing tolerance index decreased. Dough stability, which indicates the dough strength, also found to decrease by increasing mixture of wheat bran and date powder (1:1). Furthermore, dough development time gradually increased by increasing the mixture at all levels. It was 6.04 min at level of 40% compared to the control (2.5 min). Extensograph results showed that dough energy and dough resistance to extension and proportional number also increased compared with control sample. The proportional number (R/E) ratios increased largely from 3.20 to 5.27 at the level of 40.0%. Ash and fibre contents gradually increased as the mixture levels increased. However, mineral content progressively increased by increasing the level of date powder in the mixture. Incorporation of wheat bran and date powder mixture decreased the spread of the biscuits from 55.66 to 52.82 mm without change in the thickness of the biscuits. Organoleptic properties revealed that quality of biscuits was acceptable at mixture level of 30%.

关键词： Wheat Flour Wheat Bran Palm Date Fruit Biscuit Dough Rheological Properties Nutritional Quality

Selected Aspects of Camel Immune System and Immune Responses

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Open Journal of Veterinary Medicine 2021年第6期11卷 177-211页

作者： Saeed Y. Al Ramadan Kazem T. Al-Mohammed Salem Ibrahim H. Alshubaith Ahmed M. Al-Ali salah Abohelaika Mohammed S. Moqbel Ahmed M. Alluwaimi Department of Anatomy College of Veterinary Medicine King Faisal University Al-Ahsaa Saudi Arabia Animal Resources Management Ministry of Environment Water and Agriculture Al-Ahsaa Saudi Arabia Environmental Health Department Al-Ahsaa Municipality Al-Ahsa Saudi Arabia Central Biotechnology Laboratory Veterinary Teaching Hospital College of Veterinary Medicine King Faisal University Al-Ahsaa Saudi Arabia Clinical Pharmacology Department Qatif Central Hospital Ministry of Health Saudi Arabia Department of Microbiology and Parasitology College of Veterinary Medicine King Faisal University Al-Ahsaa Saudi Arabia

The camel economy is of considerable importance for arid countries. In the last decade, studies about camel immune system and immune responses have recorded increasing interest. However, drawing a comprehensive picture of the camel immune system remains far from reached. A major part of this review is to cover the studies of the primary and secondary immune organs and the markers of the camel immune cells and certain lymphoid tissues. At the same time, immune responses to different diseases and the nature of effective immunity were included, with an emphasis on the most important zoonotic diseases in camels such as MERS CoV;brucellosis. New findings on the diversity mechanisms of camel immunoglobulin genes were addressed. However, detail of the mechanism of MHC-restricted cellular immunity and the mechanism of B lymphocyte activation in camels await further attention. Interestingly, the gross and the histological structure of the lymphoid tissues of the camel’s thymus, tonsils, and peyer’s patches have indicated significant differences from other animals in terms of structure and function. The most peculiar CD expression, such as LPAM-I, MAdCAM-1 and CX3CR1, in certain camel cells and tissues refers to possible extraordinary mechanisms of immune hemostasis in camel in comparison to other ruminants. The widely applied immunodiagnostic techniques to control camel diseases and to assist in improving the camel resistance were considered. Extensive studies of the camel immune system were greatly hampered by lack of specific reagents to camel markers and low funds in the field of camel i

关键词： Camel CX3CR1 Heavy Chain Antibody MERS-CoV Peyer’s Patches

向丙泊酚麻醉患者血管内注射含肾上腺素的硬膜外试验剂量观察灌注指数的预测效能

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麻醉与镇痛 2010年第4期6卷 53-57页

作者： Hany A. Mowafi salah A. Ismail Mohammed A. Shaft AbdulMohsin A. Al-Ghamdi 谢珺田(译) 宋文阁(校) Department of Anesthesiology Faculty of Medicine King Faisal University Saudi Arabia 不详

背景灌注指数是一种无创性的来自干血氧饱和度监测的反映外周循环灌注的指标。本研究评估了灌注指数做为探索成人丙泊酚麻醉过程中血管内注入包含15μg肾上腺素的硬膜外试验剂量药物后变化指标的有效性；同时将它与常规评估标准-心率（H... 详细信息

背景灌注指数是一种无创性的来自干血氧饱和度监测的反映外周循环灌注的指标。本研究评估了灌注指数做为探索成人丙泊酚麻醉过程中血管内注入包含15μg肾上腺素的硬膜外试验剂量药物后变化指标的有效性；同时将它与常规评估标准-心率（HR）（如果升高≥10bpm则为阳性）及收缩压（SBP）（如果升高≥15mmHg则为阳性）进行了可靠性比较。方法40例全静脉麻醉、择期行普外科手术的患者随机静脉注射3ml含5μg/ml肾上腺素浓度为15mg／ml的利多卡因或3ml生理盐水（每组n=20）。监测注射后5分钟的心率、收缩压和灌注指数（PI）。结果注射试验剂量在39±15秒后平均最大灌注指数降低65％±13％。心率和血压的最大增量分别为49±25秒后19±8bpm和102±34秒后17±7mmHg。用灌注指数作为血管内注射的评估指标（如果灌注指数较注射前降低≥10％则为阳性），其敏感性、特异性、阳性预期值和阴性预期值是100％（95％可信区间CI=83％-100％）。相对地，心率和血压指标的敏感性分别为95％（CI=76％-99％）和90％（CI=70％-97％）。结论灌注指数是评价成年丙泊酚静脉麻醉患者血管内注射硬膜外试验剂量药物后常规血流动力学变化的可靠的选用指标。

关键词：肾上腺素浓度血管内注射试验剂量麻醉过程硬膜外丙泊酚灌注患者