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Thermal Decomposition of Olive-Solid Waste by TGA: Characterization and Devolatilization Kinetics under Nitrogen and Oxygen Atmospheres

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Journal of Power and Energy Engineering 2024年第3期12卷 31-47页

作者： yahya h. Khraisha Chemical Engineering Department University of Jordan Amman Jordan

Despite the fact that a few countries in the Mediterranean and the Middle East have limited crude oil reserves, they have abundant biomass feedstocks. For instance, Jordan relies heavily on the importation of natural gas and crude oil for its energy needs;but, by applying thermochemical conversion techniques, leftover olive oil can be used to replace these energy sources. Understanding the chemical, physical, and thermal characteristics of raw materials is essential to obtaining the most out of these conversion processes. Thermogravimetric analysis was used in this study to examine the thermal behavior of olive-solid residue (kernel) at three different heating rates (5, 20 and 40 C/min) in nitrogen and oxygen atmospheres. The initial degradation temperature, the residual weight at 500 and 700˚C and the thermal degradation rate during the devolatilization stage (below 400˚C) were all determined. It was found that in N2 and O2 atmospheres, both the initial degradation temperature and the degradation rate increase with increasing heating rates. As heating rates increase in the N2 atmosphere, the residual weight at 500 or 700˚C decreases slightly, but at low heating rates compared to high heating rates in the O2 atmosphere, it decreases significantly. This suggests that a longer lignin oxidation process is better than a shorter one. Coats and Redfern approach was used to identify the mechanism and activation energy for the devolatilization stage of pyrolysis and oxidation reactions. The process mechanism analysis revealed that the model of first-order and second-order reactions may adequately describe the mechanism of heat degradation of the devolatilization step of olive-solid waste for pyrolysis and oxidation processes, respectively.

关键词： Biomass Olive-Solid Waste Thermogravimetry Pyrolysis Oxidation heating Rates Kinetics

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Mitigating diabetes-related complications:Empowering metformin with cholecalciferol and taurine supplementation in type 2 diabetic rats

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World Journal of Diabetes 2024年第8期15卷 1778-1792页

作者： Mai S Attia Fadwa Ayman Mohamed S Attia Galal yahya Mansour h Zahra Magdi Mohamed Ibrahim Khalil Abdel Aziz A Diab Department of Zoology Faculty of ScienceZagazig 44519Egypt Department of Pharmaceutics Faculty of PharmacyZagazig 44519Egypt Department of Microbiology and Immunology Faculty of PharmacyZagazig UniversityZagazig 44519Egypt Department of Biochemistry Faculty of MedicineZagazig 44519Egypt

BACKGROUND Type 2 diabetes is one of the most prevalent chronic diseases worldwide,significantly impacting patients'quality of *** treatment options like metformin(MET)effectively counteract hyperglycemia but fail to alleviate diabetes-associated complications such as retinopathy,neuropathy,nephropathy,hepatopathy,and cardiovascular *** To propose the supplementation of cholecalciferol(ChO)and taurine(TAU)to enhance MET efficacy in controlling diabetes while minimizing the risk of associated *** The study involved sixty rats,including ten non-diabetic control rats and fifty experimental rats with type 2 diabetes induced by *** experimental rats were further subdivided into positive control and treatment *** four treatment groups were randomly allocated to a single MET treatment or MET combined with supplements either ChO,TAU,or *** Diabetic rats exhibited elevated levels of glucose,insulin,homeostasis Model Assessment of Insulin Resistance(hOMA-IR),glycated hemoglobin percentage,lipid markers,aspartate aminotransferase,and malondialdehyde,along with reduced levels of antioxidant enzymes(catalase and superoxide dismutase).The administration of ChO and TAU supplements alongside MET in diabetic rats led to a noticeable recovery of islet *** antioxidative,anti-inflammatory,and anti-apoptotic properties of the proposed combination therapy significantly ameliorated the aforementioned *** The supplementation of ChO and TAU with MET showed the potential to significantly improve metabolic parameters and protect against diabetic complications through its antioxidative,anti-inflammatory,and antiapoptotic effects.

关键词： Diabetes complications Metformin Cholecalciferol Taurine Glycated hemoglobin% Antioxidant

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Spinal dural arteriovenous fistula:a comprehensive review of the history,classification systems,management,and prognosis

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Chinese Neurosurgical Journal 2024年第1期10卷 48-56页

作者： Ali Alkhaibary Ahoud Alharbi Nada Alnefaie hajar Alammar Alshaymaa M.Arishy Noor Alghanim Yazeed M.Aldhfyan Arwa Albaiahy yahya h.khorm. Wael Alshaya Saad AlQahatani Ahmed Aloraidi Ahmed Alkhani Sami Khairy College of Medicine King Saud Bin Abdulaziz University for Health SciencesRiyadhSaudi Arabia King Abdullah International Medical Research Center RiyadhSaudi Arabia Division of Neurosurgery Department of SurgeryKing Abdulaziz Medical CityMinistry of National Guard-Health AffairsRiyadhSaudi Arabia Department of Neurosurgery National Neurosciences InstituteKing Fahad Medical CityRiyadhSaudi Arabia College of Medicine Jazan UniversityJazanSaudi Arabia Department of Neurosurgery King Faisal Specialist Hospital and Research CenterRiyadhSaudi Arabia Department of Surgery Faculty of MedicineJazan UniversityJazanSaudi Arabia

Spinal dural arteriovenous fistulas account for the majority of spinal vascular *** are typically located in the thoracolumbar region and are diagnosed in the middle-aged and elderly *** spinal dural arteriovenous fistulas have been postulated to be acquired,their exact development remains ***,the arteriovenous shunt is situated close to the spinal nerve root,inside the dura mater,where the blood from the radiculomeningeal artery and radicular vein *** history,there have been multiple classification systems of spinal arteriovenous shunts since *** were mainly based on the evolution of diagnostic studies as well as the treatment of these *** classification systems have undergone significant changes over the *** intracranial dural arteriovenous fistula,spinal dural arteriovenous fistula is progressive in *** neurological manifestations,due to venous congestion,tend to be insidious as well as *** include sensory deficits,such as paresthesia,bilateral and/or unilateral radicular pain affecting the lower limbs,and gait *** dural arteriovenous fistulas can be suspected on magnetic resonance imaging/magnetic resonance angiography and confirmed by digital subtraction angiography(DSA).The management includes surgery,endovascular therapy,and in selected cases,*** treatment goal of spinal dural arteriovenous fistula is to halt the progression of the *** prognosis depends on both the duration of symptoms as well as the clinical condition prior to *** present article comprehensively reviews the pathophysiology,changes in classification systems,natural history,clinical manifestations,radiological features,management,and prognosis.

关键词： Connection Endovascular Myelopathy Vascular

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Identification Schemes for Unmanned Excavator Arm Parameters

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International Journal of Automation and computing 2008年第2期5卷 185-192页

作者： yahya h.Zweiri Department of Mechanical Engineering Mu'tah University

Parameter identification is a key requirement in the field of automated control of unmanned excavators （UEs）. Furthermore, the UE operates in unstructured, often hazardous environments, and requires a robust parameter identification scheme for field applications. This paper presents the results of a research study on parameter identification for UE. Three identification methods, the Newton-Raphson method, the generalized Newton method, and the least squares method are used and compared for prediction accuracy, robustness to noise and computational speed. The techniques are used to identify the link parameters （mass, inertia, and length） and friction coefficients of the full-scale UE. Using experimental data from a full-scale field UE, the values of link parameters and the friction coefficient are identified. Some of the identified parameters are compared with measured physical values. Furthermore, the joint torques and positions computed by the proposed model using the identified parameters are validated against measured data. The comparison shows that both the Newton-Raphson method and the generalized Newton method are better in terms of prediction accuracy. The Newton-Raphson method is computationally efficient and has potential for real time application, but the generalized Newton method is slightly more robust to measurement noise. The experimental data were obtained in collaboration with QinetiQ Ltd.

关键词： Parameters identification complex dynamic systems Newton-Raphson method generalized Newton method least squares method full-scale validation

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Effects of Increasing Tungsten on Structural,Elastic and Optical Properties of xWO_3-(40-x)Ag_2O-60Te_2O Glass System

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Journal of Materials Science & Technology 2015年第1期31卷 83-90页

作者： MM.Umair A.K.yahya M.K.halimah h.A.A.Sidek School of Physics and Materials Studies Universiti Teknologi MARA Department of Physics Faculty of ScienceUniversiti Putra Malaysia

Ternary teiiurite glasses with composition of xWO3（40-x）Ag2O-60TeO2（x=0-40 mol%） have been prepared by melt-quenching *** and optical properties of the glass system were obtained by ultrasonic velocity measurements and UV-vis spectroscopy,respectively,while structural investigation was carried out by using Raman *** longitudinal and shear velocities,vLand vsshowed large increase at x from 0 to 20 mol%before decrease with further addition of *** longitudinal modulus CLand shear modulus μ bulk modulus KeYoung’s modulus Vand Debye temperature θDshowed similar behaviors to both *** large increase of the elastic moduli at x from 0 to 20 mol%is suggested to be due to the increase in WO6octahedral unit structure indicating the increase of bridging oxygen（BO） and formation of stronger Te-O-W bonds compared to Te-O-Te *** the other hand,forx> 20 mol%,the decrease in the elastic moduli was due to the increase of non-bridging oxygen（NBO） as a result of formation of WO4tetrahedral via breaking Te-O-W *** analysis by using bulk compression and ring deformation models showed a slight decrease in the ratio of ideal bulk modulus Kbcto the experimental bulk modulus Keand average atomic ring size,/ for× 20 mol%.Our analysis also indicates that limited ring deformation took place and the main compression mechanism in this glass system was mainly ideal isotropic *** the other hand,optical band gap Eoptshowed small variation for x=0-20 mol%but decreased upon higher WO3content while refractive index n showed the opposite *** optical behavior is suggested to be related to the changes in cross link density and NBO concentration in the glass system.

关键词： Elastic moduli Optical absorption Raman spectrosco

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Impact of device resistances in the performance of graphene-based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期 89-99页

作者： óscar Castelló Sofía M.López Baptista Kenji Watanabe Takashi Taniguchi Enrique Diez Jesús Enrique Velázquez-Pérez yahya M.Meziani José M.Caridad Juan A.Delgado-Notario Department of Applied Physics University of Salamanca Unidad de Excelencia en Luz y Materia Estructurada(LUMES) University of Salamanca Research Center for Electronic and Optical Materials National Institute for Materials Science Research Center for Materials Nanoarchitectonics National Institute for Materials Science Nanotechnology Group USAL–Nanolab University of Salamanca

In recent years, graphene field-effect-transistors(GFETs) have demonstrated an outstanding potential for terahertz(Thz) photodetection due to their fast response and high-sensitivity. Such features are essential to enable emerging Thz applications, including 6G wireless communications, quantum information, bioimaging and security. however, the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device, so-called access or parasitic resistances. In this work, we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFET detectors. Such dual-gate architectures allow us to fine tune(decrease) the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector, respectively. Our results can be well understood by a series resistance model, as shown by the excellent agreement found between the experimental data and theoretical calculations. These findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

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Catalytic effect of SrTiO_3 on the hydrogen storage behaviour of Mgh_2

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Journal of Energy Chemistry 2019年第1期28卷 46-53页

作者： M.S.yahya M.Ismail School of Ocean Engineering University Malaysia Terengganu

The effects of Sr TiO_3 on the hydrogen storage properties of Mgh_2 have been studied for the first *** onset dehydrogenation temperature of the Mgh_2-10 wt% SrTiO_3 is found to be 275 ℃, which is 55 ℃ lower as compared to the as-milled Mgh_2. The composite is able to absorb 4.3 wt% of hydrogen in 60 min instead of 1.1 wt% for the as-milled Mg h_2. Meanwhile, the composite is able to release 5.3 wt% of hydrogen in 17 min compared to 1.9 wt% by the as-milled Mg h_2 at 320 ℃. The calculated Eaof the Mg h_2-10 wt% SrTiO_3 is 109 k J/mol, which is 26.3 kJ/mol lower than the calculated Eaof the as-milled Mgh_2. The Sr TiO_3 is not decomposed during the ball milling and the re/dehydrogenation processes. The catalytic effect shown by the SrTiO_3 is owing to its ability to change the physical structure of the Mgh_2 particles during the ball milling process.

关键词： hydrogen storage Magnesium hydride Catalytic effect Sorption properties

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Influence of nickel addition on the microstructure and mechanical properties of Al2O3–5vol%ZrO2 ceramic composites prepared via precipitation method

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International Journal of Minerals,Metallurgy and Materials 2019年第7期26卷 908-914页

作者： Betül Kafkasl?o?lu Y?ld?z hüseyin Y?lmaz yahya Kemal Tür Department of Materials Science and Engineering Gebze Technical University

The aim of this work was to investigate the microstructure and mechanical properties of 1vol%-Ni-added yttria-stabilized zirconia (YSZ) toughened alumina composites. First, Ni powders were heterogeneously precipitated in an alumina–zirconia powder mixture suspended in water;the prepared specimens were then pressureless sintered at 1550°C/2 h in a 90vol%Ar/10vol% h2 atmosphere. The structure of phases and microstructure of the composites were characterized by X-ray diffraction and scanning electron microscopy, respectively. Mechanical characterization of the specimens was carried out through Vickers hardness, Vickers indentation toughness, and three-point flexural bending tests. The fine Ni particles were homogeneously dispersed throughout the alumina matrix because of the employed processing method. Furthermore, hardness and toughness values were found to increase by 8% and 50%, respectively, with Ni addition, whereas the relative densities and flexural strength values were found to remain unchanged.

关键词： alumina zirconia ceramic matrix microstructure hardness strength toughness

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Studies on product distribution of alkali promoted iron catalyst in Fischer-Tropsch synthesis

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Journal of Natural Gas Chemistry 2010年第1期19卷 31-34页

作者： Ali Nakhaei Pour Masoud Zare yahya Zamani Research Institute of Petroleum Industry National Iranian Oil Company P.O.Box 14665-137 Tehran Iran

The dependencies of hydrocarbon product distributions of alkali promoted iron catalyst in Fischer-Tropsch synthesis have been studied. The concept of two superimposed Anderson-Schulz-Flory distributions has been applied for the representation of the effects of Mg, La and Ca promoters on product distributions. The FTS performance of the catalysts was tested in a fixed bed reactor under the conditions 563 K, 1.7 MPa, h2/CO = 1 and space velocities 4.86 and 13.28 nl·h^-1·gFe^-1. The results indicate that appropriate amounts of these promoters enhance the break in ASF distributions in the order Ca 〉 Mg 〉 La because of the rising of the catalyst surface basicity.

关键词： chain length distribution Fischer-Tropsch synthesis Fe catalyst

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Arterial complication of irreversible electroporation procedure for locally advanced pancreatic cancer

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World Journal of Gastrointestinal Oncology 2016年第10期8卷 751-756页

作者： yahya Ekici Tugan Tezcaner hüseyin Onur Aydin Fatih Boyvat G?khan Moray Department of General Surgery Medical Faculty of Baskent University Department of Radiology Medical Faculty of Baskent University

Irreversible electroporation(IRE) is a non-thermal ablation technique used especially in locally advanced pancreatic carcinomas that are considered surgically *** present the first case of acute superior mesenteric artery(SMA) occlusion secondary to pancreatic IRE procedure that has not been reported before in the literature.A 66-year-old man underwent neoadjuvant chemoradiotherapy for locally advanced pancreatic ductal *** procedure was applied to the patient during laparotomy under general *** finishing the procedure,an acute intestinal ischemia was detected.A conventional vascular angiography was performed and a metallic stent was successfully placed to the SMA and blood flow was *** is important to be careful in such cases of tumor involvement of SMA when evaluating for IRE procedure of pancreatic tumor.

关键词： Irreversible electroporation Mesenteric artery occlusion Locally advanced pancreatic cancer Superior mesenteric artery

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