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CO oxidation and 4-nitrophenol reduction over ceria-promoted platinum nanoparticles impregnated with ZSm-5 zeolite

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Journal of Rare Earths 2022年第8期40卷 1247-1254页

作者： Zeinhom m.El-Bahy mohammed T.Alotaibi salah m.El-Bahy Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City11884CairoEgypt Department of Chemistry Turabah University CollegeTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

Active new ceria-promoted platinum supported on ZSm-5 catalysts were prepared and characterized by X-ray diffraction(XRD),Fourier transform infrared spectra(FTIR),transform electron microscopy(TEm),temperature programmed desorption(TPD),and FTIR of CO *** samples were prepared by the incipient wetness impregnation method and calcined at 500℃.The XRD patterns and FTIR spectra prove that the zeolite framework is kept unaltered after metal *** images prove the presence of Pt nanoparticles with particle size starting from 14 to 27 *** FTIR data suggest the formation of Pt-O-Ce ***-situ FTIR of CO adsorption over reduced samples proves the presence of Pt~0 only,and no Pt^(n+)-CO species are *** prepared catalysts were tested in both oxidation reaction(CO oxidation) in the gas phase and in reduction reaction(4-nitrophenol reduction) in the aqueous ***,CO oxidation by O_(2) results in the formation of a CO_(2) peak at 2347 cm^(-1) as the only CO oxidation product in the studied frequency *** intensity of the CO_(2) peak increases after the addition of Ce,and it is 4 times higher in Pt_(1) Ce_(0.5)ZSm-5 than that in the Ce-free *** to the FTIR data and previous reports,the increase in the catalytic activity may be due to the formation of Pt-O-Ce ***,Ce-promoted Pt_(1) ZSm5 also exhibits enhanced catalytic activity towards the reduction of 4-nitrophenol to 4-aminophenol by NaBH_(4) in the aqueous *** first-order rate constant of the reduction increases ≈13 times after incorporating equal ratios of Pt and Ce(Pt_(1) Ce_(1)ZSm-5),and the activation energy(E_(a)) decreases to 40% of that in the reaction over Pt_(1) ZSm-5.

关键词： 4-Nitrophenol CO oxidation TPD-CO Platinum-cerium ZSm-5 Rare earths

Industrial Food Quality Analysis Using New k-Nearest-Neighbour methods

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Computers, materials & Continua 2021年第5期67卷 2681-2694页

作者： Omar Fetitah Ibrahim m.Almanjahie mohammed Kadi Attouch salah Khardani Laboratory of Statistics and Stochastic Processes University of Djillali LiabesSidi Bel Abbes22000Algeria Department of mathematics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia Statistical Research and Studies Support Unit King Khalid UniversityAbha62529Saudi Arabia Facultédes sciences de Tunis Laboratoire des Réseaux Intelligents et NanotechnologieTunisTunisia

The problem of predicting continuous scalar outcomes from functional predictors has received high levels of interest in recent years in many fields,especially in the food *** k-nearest neighbor(k-NN)method of Near-Infrared Reflectance(NIR)analysis is practical,relatively easy to implement,and becoming one of the most popular methods for conducting food quality based on NIR *** k-NN is often named k nearest neighbor classifier when it is used for classifying categorical variables,while it is called k-nearest neighbor regression when it is applied for predicting noncategorical *** objective of this paper is to use the functional Near-Infrared Reflectance(NIR)spectroscopy approach to predict some chemical components with some modern statistical models based on the kernel and k-Nearest Neighbour *** this paper,three NIR spectroscopy datasets are used as examples,namely Cookie dough,sugar,and tecator ***,we propose three models for this kind of data which are Functional Nonparametric Regression,Functional Robust Regression,and Functional Relative Error Regression,with both kernel and k-NN approaches to compare between *** experimental result shows the higher efficiency of k-NN predictor over the kernel *** predictive power of the k-NN method was compared with that of the kernel method,and several real data sets were used to determine the predictive power of both methods.

关键词： Functional data analysis classical regression robust regression relative error regression kernel method k-NN method near-infrared spectroscopy

Robust nonlinear control strategy to maximize energy capture in a variable speed wind turbine with an internal induction generator

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控制理论与应用（英文版） 2012年第2期10卷 184-194页

作者： Erhun IYASERE mohammed H. salah Darren m. DAWSON John R. WAGNER Enver TATLICIOGLU Jacobsen a Textron CompanyCharlotteNCU.S.A. Department of mechatronics Engineering Hashemite UniversityZarqaJordan Department of Electrical & Computer Engineering Clemson UniversityClemsonSCU.S.A. Department of mechanical Engineering Clemson UniversityClemsonSCU.S.A. Department of Electrical & Electronics Engineering Izmir Institute of TechnologyIzmirTurkey

This paper proposes a control strategy to maximize the wind energy captured in a variable speed wind turbine, with an internal induction generator, at low to medium wind speeds. The proposed strategy controls the tipspeed ratio, via the rotor angular speed, to an optimum point at which the efficiency constant （or power coefficient） is maximum for a particular blade pitch angle and wind speed. This control method allows for aerodynan^c rotor power maximization without exact wind turbine model knowledge. Representative numerical results demonstrate that the wind turbine can be controlled to achieve near maximum energy capture.

关键词： Robust nonlinear control maximum energy capture Wind turbine

multi-mode Frequency Reconfigurable Conformal Antenna for modern Electronic Systems

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Computers, materials & Continua 2022年第11期73卷 3861-3877页

作者： Abir Zaidi Esraa mousa Ali Abdullah G.Alharbi salah Ud-Din Khan mohammad Alsharef mohammed S.Alzaidi Sherif S.m.Ghoneim Laboratory EEA&TI Faculty of Science and Techniques(FSTM)MohammediaHassan II UniversityCasablancaMorocco Faculty of Aviation Sciences Amman Arab UniversityAmman11953Jordan Department of Electrical Engineering Faculty of EngineeringJouf UniversitySakaka42421Saudi Arabia Sustainable Energy Technologies Center College of EngineeringKing Saud UniversityP.O.Box 800Riyadh11421Saudia Arabia Electrical Engineering Department College of EngineeringTaif UniversityP.O.Box 11099Taif21944Saudi Arabia

The article presents a miniaturized monopole antenna dedicated to modern flexible electronic *** antenna combines three fundamental properties in a single ***,it is characterized by a compact size compared to the state-of-the-art literature with an overall size of 18×18×0.254 mm3,secondly,the proposed antenna integrates the reconfigurability function of frequency,produced by means of a Positive-IntrinsicNegative(PIN)diode introduced into the radiating ***,the antenna is able to switch between different frequencies and different modes,making it suitable to meet the ever-changing demands of communication ***,the antenna is equipped by the property of *** fact,a conformability test is performed and has demonstrated the stability of the antenna performance under normal and bending ***,in order to demonstrate the potential of the proposed antenna,a comparison between the simulated and measured results is made and turned out to be a strong agreement,making the antenna an excellent candidate for future miniaturized rigid and conformal devices.

关键词： monopole antenna frequency reconfigurable co-planar waveguide(CPW)fed flexible electronics compact size

Reactivity of 1-methylisoquinoline synthesis of pyrazolyl triazoloisoquinoline and thia-diazolyl isoquinoline derivatives

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Natural Science 2011年第8期3卷 651-660页

作者： hamdi m Hassaneen Huwaida m. E Hassaneen Yasmin Sh mohammed Department of Chemistry Faculty of Science Cairo University Cairo Egypt

The reaction of 1-methylisoquinoline 1 with hy-drazonoyl halides 2 in ethanol in the presence of chitosan under microwave irradiation affords triazoloisoquinoline 4. Product 4 reacts with dimethylformamide-dimethylacetal to give ena- minones 7 which react with hydrazonoyl halides to give pyrazolyl triazoloisoquinoline 13. Also, 1-methylisoquinoline 1 reacts with arylisothio-cyanate to give thioanilide 15 which reacts with hydrazonoyl halides to give the corresponding thiadiazolyl isoquinoline derivatives 20, 24.

关键词： [1 2 4]Triazolo[3 4-a]isoquinolines Enaminones Hydrazonoyl Halides Cycloaddition Reactions Chitosan Thioanilides 3 4]Thiadiazolylisoquinoline Derivatives

Outcome of Early Surgical Decompression in Traumatic Incomplete Spinal Cord Injury

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Open Journal of modern Neurosurgery 2020年第3期10卷 353-363页

作者： mohammed Ahmed Eissa Ahmed Elsharkawy Hieder Al-Shami Aya Ouf Ahmed m. salah El-Din Department of Neurosurgery Cairo University Cairo Egypt Department of Neurosurgery Al-Ahly Bank Hospital Cairo Egypt School of medicine Cairo University Cairo Egypt

Objectives: Central cord syndrome has been reported to occur with particular frequency among older persons with cervical spondylosis who sustain hyperextension neck injury. This study aims to determine the efficacy of early surgical decompression (within 24 hours) of traumatic central cord syndrome patients in comparison with conservative management for central cord syndrome to determine a line of management to these cases. methods: 60 patients suffering from acute traumatic central cord syndrome with various neurological deficits were divided into 2 groups, group A (conservatively managed) and group B (surgically managed). Patients in group B were operated upon within 24 hr. of trauma by posterior decompression. Clinical assessment of each patient on admission, discharge and 3 months follow-ups was done using the ASIA Impairment Scale, FIm, Ashworth scale, bladder function, and neuropathic pain symptoms. Results: Data collected from both groups showed, group A (the conservative group) consisted of 22 male (73.3%) and 8 female subjects (26.6%) with a mean age of 57.5 years while in group B (surgical group) the sample consisted of 20 male (66.6%) and 10 female subjects (33.3%) with a mean age of 58.6 years. There was an improvement in our study—according to ASIA and FIm scales—in 8 patients of 30 (26.6%) in the conservative group. In the surgical group, improvement in 16 patients (53.3%). Conclusions: Early surgical decompression with laminectomy and duroplasty can be considered a reliable modality in the management of traumatic CCS and can effectively reduce the secondary injury of the spinal cord and consequent deterioration with less hospital stay.

关键词： Central Cord Syndrome “CCS” Early Surgical Decompression Laminectomy Duroplasty

Square Patch Antenna for Breast Cancer Diagnosis at 2.45 GHz

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Circuits and Systems 2019年第4期10卷 45-53页

作者： mussa Elsaadi Hend muhmed mohammed Abd Alraheem Hajir miftah Omar salah Electronic and Electrical Engineering Tobruk University Tobruk Libya

This paper presents a model of cancer diagnosis using principal electrical parameters of tumor cells such as the relative permittivity and the conductivity. The proposed model involves a square microstrip antenna and breast phantom comprising a tumor cell. The radiation properties of the designed antenna at the ISm bands, such as the Return Loss (RL), the current density, the electrical field and the Specific Absorption Rate (SAR) are exploited for diagnosing purposes. The Ansoft HFSS (13.0) simulated results show that the difference in terms of the RL, the current density, the electrical field and the SAR is higher than 2 dB, 40 A/m2, 100 V/m and 20 W/kg respectively, once the tumor exists inside the breast model. This proposed technique in turn can be exploited to distinguish malignant cells inside the women breast in earlier stages as compared to other traditional techniques such as mammography, X-ray, ultra-sound, tomography and mRI.

关键词： Breast Cancer Tumor Cells microstrip Antenna Cancer Detection

Intensive care unit readmission in adult Egyptian patients undergoing living donor liver transplant:A single-centre retrospective cohort study

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World Journal of Hepatology 2022年第6期14卷 1150-1161页

作者： manar salah Iman Fawzy montasser Hanaa A El Gendy Alaa A Korraa Gamal m Elewa Hany Dabbous Hossam R mahfouz mostafa Abdelrahman mohammed Hisham Goda mohamed mohamed Bahaa El-Din mahmoud El-meteini Heba A Labib Department of Tropical medicine Ain Shams Center for Organ TransplantationAin Shams UniversityCairo 11566Egypt Department of Anaesthesia and Critical Care Ain Shams Centre for Organ TransplantationAin Shams UniversityCairo 11566Egypt Department of General Surgery and Liver Transplantation Ain Shams Centre for Organ TransplantationAin Shams UniversityCairo 11566Egypt

BACKGROUND Patients who undergo living donor liver transplantation(LDLT)may suffer complications that require intensive care unit(ICU)*** To identify the incidence,causes,and outcomes of ICU readmission after *** A retrospective cohort study was conducted on patients who underwent *** collected data included patient demographics,preoperative characteristics,intraoperative details;postoperative stay,complications,causes of ICU readmission,and *** were divided into two groups according to ICU readmission after hospital *** factors for ICU readmission were identified in univariate and multivariate *** The present study included 299 ***-one(10.4%)patients were readmitted to the ICU after *** who were readmitted to the ICU were older in age(53.0±5.1 vs 49.4±8.8,P=0.001)and had a significantly higher percentage of women(29%vs 13.4%,P=0.032),diabetics(41.9%vs 24.6%,P=0.039),hypertensives(22.6%vs 6.3%,P=0.006),and renal(6.5%vs 0%,P=0.010)patients as well as a significantly longer initial ICU stay(6 vs 4 d,respectively,Pmission included recipient age(OR=1.048,95%CI=1.005-1.094,P=0.030)and length of initial hospital stay(OR=0.836,95%CI=0.789-0.885,Pmay help provide optimal care and tailor follow-up to reduce the rate of ICU readmission.

关键词： Intensive care units Liver transplantation Patient readmission Risk factors

High prevalence of chronic viral hepatitis B and C in minnesota Somalis contributes to rising hepatocellular carcinoma incidence

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World Journal of Gastroenterology 2022年第35期28卷 5217-5229页

作者： Essa A mohamed Nasra H Giama Abubaker O Abdalla Hassan m Shaleh Abdul m Oseini hamdi A Ali Fowsiyo Ahmed Wesam Taha Hager Ahmed mohammed Jessica Cvinar Ibrahim A Waaeys Hawa Ali Loretta K Allotey Abdiwahab O Ali Safra A mohamed William S Harmsen Eimad m Ahmmad Numra A Bajwa mohamud D Afgarshe Abdirashid m Shire Joyce E Balls-Berry Lewis R Roberts Division of Gastroenterology and Hepatology Mayo ClinicRochesterMN 55905United States Center for Clinical and Translational Science Mayo ClinicRochesterMN 55905United States School of Nursing University of MinnesotaMinneapolisMN 55455United States Division of Digestive Diseases Emory School of MedicineAtlantaGA 30322United States Department of Laboratory medicine and Pathology Mayo ClinicRochesterMN 55905United States Department of Internal medicine NewYork-Presbyterian QueensFlushingNY 11355United States Department of Pediatrics University of Nevada Las VegasLas VegasNV 89154United States Department of Quantitative Health Sciences Mayo ClinicRochesterMN 55905United States Department of medicine Gargar Urgent Care and ClinicMinneapolisMN 55406United States Office of the Director Shire ScientificMinneapolisMN 55405United States Department of Neurology Washington University School of Medicine in St LouisSt LouisMO 63130United States Knight Alzheimer Disease Research Center Washington University School of MedicineSt LouisMO 63130United States

BACKGROUND Chronic hepatitis B virus(HBV)and hepatitis C virus(HCV)infections are known risk factors for liver disease,cirrhosis and hepatocellular carcinoma(HCC).There is substantial global variation in HBV and HCV prevalence resulting in variations in cirrhosis and *** previously reported high prevalence of HBV and HCV infections in Somali immigrants seen at an academic medical center in *** To determine the prevalence of chronic viral hepatitis in Somali immigrants in minnesota through a community-based screening *** We conducted a prospective community-based participatory research study in the Somali community in minnesota in partnership with community advisory boards,community clinics and local mosques between November 2010 and December 2015(data was analyzed in 2020).Serum was tested for hepatitis B surface antigen,hepatitis B core antibody,hepatitis B surface antibody and anti-HCV *** Of 779 participants,15.4%tested positive for chronic HBV infection,50.2%for prior exposure to HBV and 7.6%for chronic HCV *** age-adjusted frequencies in males and females for chronic HBV were 12.5%and 11.6%;for prior exposure to HBV were 44.8%and 41.3%;and for chronic HCV were 6.7%and 5.7%,*** participants developed incident HCC during follow *** Chronic HBV and HCV are major risk factors for liver disease and HCC among Somali immigrants,with prevalence of both infections substantially higher than in the general United States ***-based screening is essential for identifying and providing health education and linkage to care for diagnosed patients.

关键词： Viral hepatitis Liver disease Community engagement African Immigrant health