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

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

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WEIGHTED PSEUDO ALmOST-PERIODIC SOLUTIONS OF SHUNTING INHIBITORY CELLULAR NEURAL NETWORKS WITH mIXED DELAYS

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Acta mathematica Scientia 2016年第6期36卷 1662-1682页

作者： mohammed salah m'HAmDI Chaouki AOUITI Abderrahmane TOUATI Adel m. ALImI Vaclav SNASEL Department of mathematics University of Carthage Faculty of Sciences of Bizerta BP W 7021 Zarzouna Bizerta Tunisia REGIm-lab: Research Groups on Intelligent machines University of Sfax National Engineering School of Sfax (ENIS) BP 1173 Sfax 3038 Tunisia VSB Technical University of Ostrava Czech Republic

In this paper, we prove the existence and the global exponential stability of the unique weighted pseudo almost-periodic solution of shunting inhibitory cellular neural networks with mixed time-varying delays comprising different discrete and distributed time delays. Some sufficient conditions are given for the existence and the global exponential stability of the weighted pseudo almost-periodic solution by employing fixed point theorem and differential inequality techniques. The results of this paper complement the previously known ones. Finally, an illustrative example is given to demonstrate the effectiveness of our results.

关键词： weighted pseudo almost-periodic solution shunting inhibitory cellular neuralnetworks mixed delays global exponential stability

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Unconstrained Hand Dorsal Veins Image Database and Recognition System

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Computers, materials & Continua 2022年第12期73卷 5063-5073页

作者： mustafa m.Al Rifaee mohammad m.Abdallah mosa I.salah Ayman m.Abdalla Faculty of Science and Information Technology Al-Zaytoonah University of JordanAmman11733Jordan Faculty of Architecture and Design Al-Zaytoonah University of JordanAmman11733Jordan

Hand veins can be used effectively in biometric recognition since they are internal organs that,in contrast to fingerprints,are robust under external environment effects such as dirt and paper ***,they form a complex rich shape that is unique,even in identical twins,and allows a high degree of ***,most currently employed hand-based biometric systems rely on hand-touch devices to capture images with the desired *** the start of the COVID-19 pandemic,most handbased biometric systems have become undesirable due to their possible impact on the spread of the ***,new contactless hand-based biometric recognition systems and databases are desired to keep up with the rising hygiene *** contribution of this research is the creation of a database for hand dorsal veins images obtained contact-free with a variation in capturing distance and rotation *** database consists of 1548 images collected from 86 participants whose ages ranged from 19 to 84 *** the other research contribution,a novel geometrical feature extraction method has been developed based on the Curvelet *** method is useful for extracting robust rotation invariance features from vein *** database attributes and the veins recognition results are analyzed to demonstrate their efficacy.

关键词： Biometric recognition contactless hand biometrics veins recognition Curvelet transform image segmentation feature extraction

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A Proposed Design, Implementation and Control of Doubly Fed Switched Reluctance motor

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CES Transactions on Electrical machines and Systems 2019年第1期3卷 101-106页

作者： Eid Gouda m.salah H. the Electrical Engineering Department Faculty of EngineeringMansoura University35516Egypt

In this paper,rotor of switched reluctance motor(SRm)is employed by mounting copper windings on the rotor poles as well as the stator *** and stator windings are excited from DC supply in order to increase the developed electro-magnetic torque;thus enhancing the output power of the drive and keeping the system ***,the proposed SRm offers higher reliability than conventional one,if excitation of rotor windings is lost,the drive will turn into a conventional SRm,the drive will continue running as a conventional *** element method magnetics(FEmm)software is applied to obtain the magnetic characteristics of the proposed SRm.A control strategy for excitation of rotor and stator windings is ***/Simulink modeling of the proposed SRm is given and validated by practical *** Results on a prototype show that the proposed SRm is capable of achieving an increased torque compared with conventional SRm drive.

关键词： Doubly Fed SRm SRm Control Wounded Rotor.

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Testing the validity of the Ehrenfest theorem beyond simple static systems: Caldirola–Kanai oscillator driven by a time-dependent force

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Chinese Physics B 2016年第8期25卷 15-20页

作者： Salim medjber Hacene Bekkar salah menouar Jeong Ryeol Choi Department of material Science Faculty of Science University of M’sila Faculty of Technology University of Ferhat Abbas Setif 1 Laboratory of Optoelectronics and Compounds (LOC) Department of Physics Faculty of Science University of Ferhat Abbas Setif 1 Department of Radiologic Technology Daegu Health College

The relationship between quantum mechanics and classical mechanics is investigated by taking a Gaussian-type wave packet as a solution of the Schr o¨dinger equation for the Caldirola–Kanai oscillator driven by a sinusoidal force. For this time-dependent system, quantum properties are studied by using the invariant theory of Lewis and Riesenfeld. In particular,we analyze time behaviors of quantum expectation values of position and momentum variables and compare them to those of the counterpart classical ones. Based on this, we check whether the Ehrenfest theorem which was originally developed in static quantum systems can be extended to such time-varying systems without problems.

关键词： Ehrenfest theorem time-dependent Hamiltonian system invariant theory

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Fracture resistance of posterior teeth restored with modern restorative materials

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The Journal of Biomedical Research 2011年第6期25卷 418-424页

作者： Ibrahim m. Hamouda salah H. Shehata Department of Biomaterials Mansoura University Al-Gomhoria St Mansoura 35516 Egypt Department of Conservative Dentistry Mansoura University Al-Gomhoria St Mansoura 35516 Egypt

We studied the fracture resistance of maxillary premolars restored with recent restorative materials. Fifty maxillary premolars were divided into five groups： Group 1 were unprepared teeth; Group 2 were teeth prepared without restoration; Group 3 were teeth restored with tetric ceram HB; Group 4 were teeth restored with InTen S; and Group 5 were teeth restored with Admira. The samples were tested using a universal testing machine. Peak loads at fracture were recorded. The teeth restored with Admira had the highest fracture resistance followed by those restored with InTen-S and tetric ceram HB. Prepared, unrestored teeth were the weakest group. There was a significant difference between the fracture resistance of intact teeth and the prepared, unrestored teeth. There was also a significant difference among the tested restorative materials. Teeth restored with Admira showed no significant difference when compared with the unprepared teeth. It was concluded that the teeth restored with Admira exhibited the highest fracture resistance.

关键词： fracture resistance composite resin adhesives mesio-occlusal-distal (mOD) cavities

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Analysis and Characterization of Pore System and Grain Sizes of Carbonate Rocks from Southern Lebanon

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Journal of Earth Science 2023年第1期34卷 101-121页

作者： mohamed K.salah Hammad Tariq Janjuhah Josep Sanjuan Department of Geology American University of BeirutRiad El SolhBeirut11072020Lebanon Department of Geology Shaheed Benazir Bhutto UniversitySheringal KP10850Pakistan Department of Earth and Ocean Dynamics Faculty of Earth SciencesUniversity of BarcelonaBarcelona08028Spain

Carbonate rocks are common in many parts of the world, including the Eastern mediterranean, where they host significant groundwater supplies and are widely used as building and ornamental stones. The porosity of carbonate rocks plays a critical role in fluid storage and retrieval. The pore structure connectivity, in particular, controls many properties of geological formations, as well as the relationships between the properties of individual minerals and the bulk properties of the rock. To study the relationships between porosity, rock properties, pore structure, pore size, and their impact on reservoir characteristics, 46 carbonate rock samples were collected from four stratigraphic sections exposed near Sidon, South Lebanon. The studied carbonate rocks are related to marine deposits of different ages(e.g., Upper Cretaceous, Eocene, and Upper miocene). In order to understand the pore connectivity, the mICP(mercury injection capillary pressure) technique was conducted on ten representative samples. Results from the SEm analysis indicate the dominance of very fine and fine pore sizes, with various categories ranging in diameter from 0.1 to10 μm. The mICP data revealed that the pore throat radii vary widely from 0.001 to 1.4 μm, and that all samples are dominated by micropore throats. The grain size analysis indicated that the studied rocks have significant amounts of silt-and clay-size grains with respect to the coarser ‘sand-size’ particles, suggesting a high proportion of microporosity. Obtained results, such as the poorly-sorted nature of grains, high microporosity, and the high percentage of micropore throats, justify the observed low mean hydraulic radius, the high entry pressure, and the very low permeability of the studied samples. These results suggest that the carbonate rocks near Sidon(south of Lebanon) are possibly classified as non-reservoir facies.

关键词： petrophysics mercury injection capillary pressure(mICP) micrite microtexture microporosity platform carbonates southern Lebanon

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Large endoscopic mucosal resection for colorectal tumors exceeding 4 cm

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World Journal of Gastroenterology 2010年第5期16卷 588-595页

作者： Philippe Ah Soune Charles ménard Ezzedine salah Ariadne Desjeux Jean-Charles Grimaud marc Barthet Department of Gastroenterology Hpital NordChemin des Bourrely13915 Marseille cedex 20France

AIm:To evaluate the feasibility and the outcome of endoscopic mucosal resection(EmR)for large colorectal tumors exceeding 4 cm(LCRT)undergoing piecemeal resection. mETHODS:From January 2005 to April 2008,146 digestive tumors larger than 2 cm were removed with the EmR technique in our *** these,34 tumors were larger than 4 cm and piecemeal resection was carried out on 26 colorectal *** mean age of the patients was 71 *** mean follow-up duration was 12 mo. RESULTS:LCRTs were located in the rectum,left colon,transverse colon and right colon in 58%,15%, 4%and 23%of cases,*** were sessile tumors larger than 4 cm with a mean size of 4.9 cm (4-10 cm).According to the Paris classification,34%of the tumors were typeⅠs,58%typeⅡa,4%typeⅡb and 4%typeⅡ*** examination showed tubulous adenoma in 31%,tubulo-villous adenoma in 27%,villous adenoma in 42%,high-grade dysplasia in38%,in situ carcinoma in 19%of the cases and mucosal carcinoma(m2)in 8%of the *** two cases(7.7%)of procedural bleeding that occurred were managed endoscopically and one small perforation was treated with *** follow-up,recurrence of the tumor occurred in three patients(12%),three of whom received endoscopic treatment. CONCLUSION:EmR for tumors larger than 4 cm is a safe and effective procedure that could compete with endoscopic submucosal dissection,despite providing incomplete histological assessment.

关键词： Endoscopic mucosal resection Perforation Colorectal carcinoma Large polyps

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Effect of treating chronic hepatitis C with direct-acting antivirals on extrahepatic cutaneous manifestations

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World Journal of Hepatology 2020年第10期12卷 841-849页

作者： mohamed El Kassas Osama mO Hegazy Eman m salah Department of Endemic medicine Faculty of MedicineHelwan UniversityCairo 11795Egypt Department of Dermatology Venereology and AndrologyFaculty of MedicineHelwan UniversityCairo 11795Egypt

BACKGROUND Hepatitis C virus(HCV)is a disease with a significant global impact,affecting approximately 2%-2.5%of the world’s *** direct-acting antivirals(DAAs)have been introduced over the past few years with great success in viral *** association of chronic HCV infection with a wide spectrum of cutaneous manifestations has been widely reported in the *** To assess the effect of treating HCV with DAAs on the extrahepatic cutaneous manifestations of *** This prospective observational study included 1039 HCV positive Egyptian patients who were eligible to receive DAAs.A total of 30 patients were diagnosed with extrahepatic cutaneous manifestations and fulfilled the inclusion criteria of the *** these patients,6 had classic lichen planus,8 were diagnosed with psoriasis vulgaris and 16 had *** patients received DAAs from October 2018 to July 2019 in the form of a three-month course of sofosbuvir/daclatasvir *** with lichen planus or psoriasis were dermoscopically evaluated before treatment and 6 mo after treatment,while patients with hepatic pruritus were assessed using the 12-Item Pruritus Severity Scale over the same *** All patients with psoriasis showed significant improvement in all psoriatic plaques,and all patients with hepatic pruritus scored 0 on the 12-Item Pruritus Severity Scale indicating total improvement of *** addition,four of six patients with lichen planus showed complete *** Treatment of HCV with DAAs was significantly effective in improving virusrelated extrahepatic cutaneous manifestations.

关键词： Directly acting antivirals Extrahepatic manifestations Hepatitis C virus Lichen planus Pruritus Cutaneous manifestations

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Non-alcoholic fatty liver disease: The diagnosis and management

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World Journal of Hepatology 2015年第6期7卷 846-858页

作者： Shehab m Abd El-Kader Eman m salah El-Den Ashmawy Department of Physical Therapy Faculty of Applied Medical Sciences King Abdulaziz University Department of Physical Therapy for Cardiopulmonary Disorders and Geriatrics Faculty of Physical Therapy Cairo University

Non-alcoholic fatty liver disease(NAFLD) is now the most frequent chronic liver disease that occurs across all age groups and is recognized to occur in 14%-30% of the general population, representing a serious and growing clinical problem due to the growing prevalence of obesity and overweight. Histologically, it resembles alcoholic liver injury but occurs in patients who deny significant alcohol consumption. NAFLD encompasses a spectrum of conditions, ranging from benign hepatocellular steatosisto inflammatory nonalcoholic steatohepatitis, fibrosis, and cirrhosis. The majority of hepatocellular lipids are stored as triglycerides, but other lipid metabolites, such as free fatty acids, cholesterol, and phospholipids, may also be present and play a role in disease progression. NAFLD is associated with obesity and insulin resistance and is considered the hepatic manifestation of the metabolic syndrome, a combination of medical conditions including type 2 diabetes mellitus, hypertension, hyperlipidemia, and visceral adiposity. Confirmation of the diagnosis of NAFLD can usually be achieved by imaging studies; however, staging the disease requires a liver biopsy. Current treatment relies on weight loss and exercise, although various insulin-sensitizing agents, antioxidants and medications appear promising. The aim of this review is to highlight the current information regarding epidemiology, diagnosis, and management of NAFLD as well as new information about pathogenesis, diagnosis and management of this disease.

关键词： Non-alcoholic fatty liver disease Nonalcoholicsteatohepatitis Liver disease

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