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Understanding the catalytic performance and deactivation behaviour of second-promoter doped Pt/WO_(χ)/γ-Al_(2)O_(3) catalysts in the glycerol hydrogenolysis for selective and cleaner production of 1,3-propanediol

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Journal of Energy Chemistry 2024年第7期94卷 486-507页

作者： Rafik Rajjak shaikh Sittichai Damruang Rais Ahmad Khan Supareak Praserthdam Piyasan Praserthdam Center of Excellence on Catalysis and Catalytic Reaction Engineering(CECC) Department of Chemical EngineeringFaculty of EngineeringChulalongkorn UniversityBangkok 10330Thailand Department of Chemistry College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia High-Performance Computing Unit(CECC-HCU) Centre of Excellence on Catalysis and Catalytic Reaction Engineering(CECC)Department of Chemical EngineeringFaculty of EngineeringChulalongkorn UniversityBangkok 10330Thailand

The selective aqueous-phase glycerol hydrogenolysis is a promising reaction to produce commercially useful 1,3-propanediol(1,3-PDO).The Pt-WOx bifunctional catalyst can catalyse the glycerol hydrogenol-ysis but the catalyst deactivation via sintering,metal leaching,and coking can predominantly occur in the aqueous phase *** this work,the effect of reaction temperature,pressure and second promoter(Cu,fe,Rh,Mn,Re,Ru,Ir,Sn,B,and P)on catalytic performance and deactivation behaviour of Pt/WOx/-Al2O3 was *** doped with Rh,Mn,Re,Ru,Ir,B,and P,the second promoter boosts catalytic activity by promoting great dispersion of Pt on support and increasing Pt surface *** increased Bronsted acid sites lead to selective synthesis of 1,3-PDO than 1,2-propanediol(1,2-PDO).The characterization studies of fresh and spent catalysts reveal that the main cause of catalyst deactivation is the Pt sintering,as interpreted based on XRD,CO chemisorption,and TEM *** Pt sintering is affected depending on the second promoter that can either or reduce the interaction between Pt,WO_(χ)/γ and Al_(2)O_(3).As an electron acceptor of Pt in Pt/WO_(χ)/γ-Al_(2)O_(3),Re and Mn as second promoters resulted in increased Pt^(2+) on the catalytic surface,which strengthens the contact between Pt andγ-Al_(2)O_(3) and WO_(χ),resulting in a decrease in Pt *** metal leaching and coking are not affected by the presence of second *** catalyst modified with a second promoter possesses improved catalytic activity and 1,3-PDO production,however the stability continues to remain a *** present work unrav-elled the determining parameters of catalytic activity and deactivation,thus providing a promising pro-tocol toward effective catalysts for glycerol hydrogenolysis.

关键词： Glycerol hydrogenolysis 1,3-propanediol Metal-support interaction Second promoter Liquid phase Catalyst deactivation

Assessing Wind Erosion: A Review of Recent Measurement Techniques

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Open Journal of Soil Science 2024年第9期14卷 499-529页

作者： Hetti Hewage Suranjith Ariyasena Xuerui Gao sohail Ahmad Jiaqiong Zhang Xining Zhao College of Soil and Water Conservation Science and Engineering Northwest A&F University Yangling China Institute of Soil and Water Conservation Northwest A&F University Yangling China

Wind erosion represents a formidable environmental challenge and has serious negative impacts on soil health and agricultural productivity, particularly in arid and semi-arid areas. The complex dynamics of wind erosion make its large-scale monitoring and quantification a daunting task. To facilitate the monitoring and quantification of wind erosion, various scientific approaches and methods have been employed. These include sophisticated wind erosion equations and models, wind tunnel experiments, and the application of radionuclides. Additionally, researchers have assessed soil physicochemical properties, used anemometers for wind speed measurement, and deployed dust collectors for particle capture. Remote sensing technologies, wind erosion monitoring stations, and evaluations of wind barriers have also been utilized. Recently, the adoption of machine learning methods has gained popularity. Despite their value, each of these techniques has limitations in capturing the full spectrum of the wind erosion process. This paper examines these limitations and assesses the effectiveness of each method in the context of wind erosion studies. It also outlines directions for future research and suggests pathways that could enhance the understanding and management of wind erosion.

关键词： Wind Erosion Wind Erosion Models Remote Sensing Machine Learning

One-pot hydrothermal preparation of hierarchical manganese oxide nanorods for high-performance symmetric supercapacitors

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Journal of Energy Chemistry 2022年第2期31卷 116-126页

作者： Bidhan Pandit Emad S.Goda Mahmoud H.Abu Elella Aafaq ur Rehman Sang Eun Hong Sachin R.Rondiya Pranay Barkataki Shoyebmohamad f.shaikh Abdullah M.Al-Enizi Salah MEl-Bahy Kuk Ro Yoon Department of Materials Science and Engineering and Chemical Engineering Universidad Carlos III de MadridAvenida de la Universidad 3028911 LeganésMadridSpain Organic Nanomaterials Lab Department of ChemistryHannam UniversityDaejeon 34054Republic of Korea fire Protection Laboratory National Institute of Standards136Giza 12211Egypt Chemistry Department Faculty of ScienceCairo UniversityGiza 12613Egypt Graduate School of Energy Science and Technology Chungnam National University99 Daehak-roYuseong-guDaejeon 34134Republic of Korea School of Chemistry Cardiff UniversityMain BuildingPark PlaceCardiffCF103AT WalesUnited Kingdom Department of Physics Visvesvaraya National Institute of TechnologySouth Ambazari RoadNagpur-440010MaharashtraIndia Department of Chemistry College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia Department of Chemistry Turabah University CollegeTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

An eco-friendly,new,and controllable approach for the preparation of manganese oxide(a-MnO_(2))nanorods has been introduced using hydrothermal reaction for supercapacitor *** in-depth crystal structure analysis ofα-MnO_(2) is analyzed by X-ray Rietveld refinement by using full Prof program with the help of pseudo-Voigt profile *** developed a-MnO_(2) electrode attains a remarkable capacitance of 577.7 f/g recorded at a current density value of 1 A/g with an excellent cycle life when is used for 10,000 repeated cycles due to the porous nanorod-morphology assisting the ease penetration of electrolyte ions into the electroactive *** diffusive and capacitive contributions of the electrode have been estimated by considering standard numerical packages in *** successfully assembling the aqueous symmetric supercapacitor(SSC)cell by utilizing the as-preparedα-MnO_(2),an excellent capacitance of 163.5 f/g and energy density of 58.1 Wh/kg at the constant current density of 0.5 A/g are obtained with an expanded potential frame of 1.6 ***,the cell has exceptionally withstood up to 10,000 cycles with an ultimate capacitance retention of 94.1%including the ability to light an LED for 18 *** findings recommend the developed a-MnO_(2) electrode to be a highly felicitous electrode for the field of energy storage.

关键词： α-MnO_(2)nanorods Rietveld refinement Symmetrical supercapacitors High energy density

Biomathematical study of time-dependent flow of a Carreau nanofluid through inclined catheterized arteries with overlapping stenosis

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Journal of Central South University 2017年第11期24卷 2725-2744页

作者： Ashfaq Ahmed sohail Nadeem Department of Mathematics Quaid-I-Azam UniversityIslamabad 45320Pakistan

This work is concerned with the analysis of blood flow through inclined catheterized arteries having a balloon(angioplasty) with time-variant overlapping stenosis. The nature of blood in small arteries is analyzed mathematically by considering it as a Carreau nanofluid. The highly nonlinear momentum equations of nanofluid model are simplified by considering the mild stenosis case. The formulated problem is solved by a homotopy perturbation expansion in terms of a variant of the Weissenberg number to obtain explicit forms for the axial velocity, the stream function, the pressure gradient, the resistance impedance and the wall shear stress distribution. These solutions depend on the Brownian motion number, thermophoresis number, local temperature Grashof number G_r and local nanoparticle Grash of number B_r. The results were also studied for various values of the physical parameters, such as the Weissenberg number W_i, the power law index n, the taper angle φ, the maximum height of stenosis δ~*, the angle of inclination α, the maximum height of balloon σ~*, the axial displacement of the balloon z_d~*,the flow rate f and the froud number fr. The obtained results show that the transmission of axial velocity curves through a Newtonian fluid(Wi=0, n=1, Gr=0, Br=0, Nt=0, Nb≠0) is substantially lower than that through a Carreau nanofluid near the wall of balloon while the inverse occurs in the region between the balloon and stenosis. The streamlines have a clearly distinguished shifting toward the stenotic region and this shifting appears near the wall of the balloon, while it has almost disappeared near the stenotic wall and the trapping bolus in the case of horizontal arteries and Newtonian fluid(Wi=0, n=1, Gr=0, Br=0, Nt=0, Nb≠0) does not appear but for the case of Carreau nanofluid bolus appears.

关键词： overlapping stenosed artery nanofluid Grashof number Brownian motion thermophoresis pharmacology

Numerical Solutions for Heat Transfer of An Unsteady Cavity with Viscous Heating

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Computers, Materials & Continua 2021年第7期68卷 319-336页

作者： H.f.Wong Muhammad sohail Z.Siri N.f.M.Noor Institute of Mathematical Sciences Faculty of ScienceUniversity of Malaya50603 Kuala LumpurMalaysia Unit of Engineering Design and Product Development Technology and Engineering DivisionMalaysian Rubber Board47000 Sungai BulohMalaysia Department of Applied Mathematics&Statistics Institute of Space Technology44000 IslamabadPakistan

The mechanism of viscous heating of a Newtonian fluid filled inside a cavity under the effect of an external applied force on the top lid is evaluated numerically in this *** investigation is carried out by assuming a two-dimensional laminar in-compressible fluid flow subject to Neumann boundary conditions throughout the numerical iterations in a transient *** the walls of the square cavity are perfectly insulated and the top moving lid produces a constant finite heat flux even though the fluid flow attains the steady-state *** objective is to examine the effects of viscous heating in the fully insulated lid-driven cavity under no-slip and free-slip Neumann boundary conditions coupled with variations in Reynolds and Prandtl *** partial differential equations of time-dependent vorticity-stream function and thermal energy are discretized and solved using a self-developed finite difference code in MATLAB®*** dependence of fluid thermodynamics is envisaged through contour and image plots.A commercial simulation software,Ansys fluent®utilizing a finite element code is employed to verify the finite difference results *** the effect of viscous heating is very minimal,Neumann no-slip and free-slip boundary conditions are able to trap the heat inside the fully insulated cavity as the heat flux is constantly supplied at the top lid.A lower Reynolds number and a greater Prandtl number with free-slip effects reduce temperature distribution in the cavity with a faster velocity than in the no-slip condition as the free-slip behaves as a lubricant.

关键词： Lid-driven viscous heating vorticity-stream function finite difference method finite element method

Wavelet Decomposition Impacts on Traditional forecasting Time Series Models

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Computer Modeling in Engineering & Sciences 2022年第3期130卷 1517-1532页

作者： W.A.shaikh S.f.Shah S.M.Pandhiani M.A.Solangi Department of Mathematics and Statistics Quaid-e-Awam University of EngineeringScience&TechnologyNawabshahSindhPakistan Department of Basic Sciences&Related Studies Mehran University of Engineering&TechnologyJamshoroSindhPakistan Department of General Studies Jubail University CollegeAl JubailSaudi Arabia

This investigative study is focused on the impact of wavelet on traditional forecasting time-series models,which significantly shows the usage of wavelet *** Decomposition(WD)algorithm has been combined with various traditional forecasting time-series models,such as Least Square Support Vector Machine(LSSVM),Artificial Neural Network(ANN)and Multivariate Adaptive Regression Splines(MARS)and their effects are examined in terms of the statistical *** WD has been used as a mathematical application in traditional forecast modelling to collect periodically measured parameters,which has yielded tremendous constructive ***,it is observed that the wavelet combined models are classy compared to the various time series models in terms of performance ***,combining wavelet forecasting models has yielded much better results.

关键词： Impact wavelet decomposition combined traditional forecasting models statistical analysis

Non-Invasive Early Diagnosis of Obstructive Lung Diseases Leveraging Machine Learning Algorithms

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Computers, Materials & Continua 2022年第9期72卷 5681-5697页

作者： Mujeeb Ur Rehman Maha Driss Abdukodir Khakimov sohail Khalid Department of Electrical Engineering Riphah International UniversityIslamabad44000Pakistan Security Engineering Lab Prince Sultan UniversityRiyadh12435Saudi Arabia RIADI Laboratory National School of Computer ScienceUniversity of ManoubaManouba2010Tunisia Peoples’friendship University of Russia(RUDN University) Moscow117198Russia

Lungs are a vital human body organ,and different Obstructive Lung Diseases(OLD)such as asthma,bronchitis,or lung cancer are caused by shortcomings within the ***,early diagnosis of OLD is crucial for such patients suffering from OLD since,after early diagnosis,breathing exercises and medical precautions can effectively improve their health state.A secure non-invasive early diagnosis of OLD is a primordial need,and in this context,digital image processing supported by Artificial Intelligence(AI)techniques is reliable and widely used in the medical field,especially for improving early disease ***,this article presents an AIbased non-invasive and secured diagnosis for OLD using physiological and iris *** research work implements different machine-learning-based techniques which classify various subjects,which are healthy and effective *** iris features include gray-level run-length matrix-based features,gray-level co-occurrence matrix,and statistical *** features are extracted from iris ***,ten different classifiers and voting techniques,including hard and soft voting,are implemented and tested,and their performances are evaluated using several parameters,which are precision,accuracy,specificity,f-score,and *** on the statistical analysis,it is concluded that the proposed approach offers promising techniques for the non-invasive early diagnosis of OLD with an accuracy of 97.6%.

关键词： Obstructive lung disease non-invasive diagnosis machine learning physiological features voting techniques

Enhanced acetone sensing performance of nanostructured Sm2O3 doped SnO2 thick films

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Journal of Rare Earths 2017年第8期35卷 813-823页

作者： f.I.shaikh L.P.Chikhale J.Y.Patil I.S.Mulla S.S.Suryavanshi School of Physical Sciences Solapur University Solapur 413255 (M.S.) lndia Council of Scientific and Industrial Research Pashan Pune 411008 India

In the present work, we synthesized Sm2O3 doped SnO2 in order to prepare a selective acetone sensor with fast response, quick recovery and good repeatability. Pure as well as 2 mol.%, 4 mol.%, 6 mol.% and 8 mol.% Sm2O3 doped SnO2 nanostructured samples were synthesized by using a co-precipitation method. The characterization of the samples was done by thermogravimetric and differential thermo-gravimetric analysis（TG-DTA）, X-ray diffraction（XRD）, field emission gun-scanning electron microscopy（fEG-SEM）, energy dispersive analysis by X-rays（EDAX）, high resolution scanning electron microscopy（HR-TEM）, selected area X-ray diffraction（SAED）, Brunauer-Emmet-Teller（BET） and ultraviolet-visible-near infrared（UV-Vis-NIR） spectroscopy techniques. The gas response studies of liquid petroleum gas, ammonia, ethanol and acetone vapor were carried out. The results showed that Sm doping systematically lowered operating temperature and enhanced the gas response and selectivity for acetone. The response and recovery time for 6 mol.% Sm2O3 doped SnO2 thick film at the operating temperature of 250 °C were 15 and 24 s, respectively.

关键词： tin oxide samarium oxide screen printing thick film acetone sensor rare earths

National guidelines for the diagnosis and treatment of hilar cholangiocarcinoma

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World Journal of Gastroenterology 2024年第9期30卷 1018-1042页

作者： faisal Saud Dar Zaigham Abbas Irfan Ahmed Muhammad Atique Usman Iqbal Aujla Muhammad Azeemuddin Zeba Aziz Abu Bakar Hafeez Bhatti Tariq Ali Bangash Amna Subhan Butt Osama Tariq Butt Abdul Wahab Dogar Javed Iqbal farooqi faisal Hanif Jahanzaib Haider Siraj Haider Syed Mujahid Hassan Adnan Abdul Jabbar Aman Nawaz Khan Muhammad Shoaib Khan Muhammad Yasir Khan Amer Latif Nasir Hassan Luck Ahmad Karim Malik Kamran Rashid sohail Rashid Mohammad Salih Abdullah Saeed Amjad Salamat Ghias-un-Nabi Tayyab Aasim Yusuf Haseeb Haider Zia Ammara Naveed Department of Hepatopancreatic Biliary Surgery&Liver Transplant Pakistan Kidney and Liver Institute&Research CentreLahore 54000Pakistan Department of Hepatogastroenterology and Liver Transplantation Dr.Ziauddin University HospitalKarachi 75600SindhPakistan University of Aberdeen Aberdeen B243FXUnited Kingdom Department of Pathology Pakistan Kidney and Liver Institute&Research CentreLahore 54000Pakistan Department of Gastroenterology&Hepatology Pakistan Kidney and Liver Institute&Research CentreLahore 54000Pakistan Department of Radiology Aga Khan UniversityKarachi 74800Pakistan Department of Oncology Hameed Latif HospitalLahore 54000Pakistan Division of Hepatopancreatic Biliary Surgery&Liver Transplantation Shifa International HospitalIslamabad 44000Pakistan Department of Hepatopancreatic Biliary Surgery&Liver Transplant Shaikh Zayed Hospital and Post Graduate Medical InstituteLahore 54000Pakistan Department of Medicine Aga Khan University HospitalKarachi 74800Pakistan Department of Liver Transplant Pir Abdul Qadir Shah Jeelani Institute of Medical SciencesGambat 66020Pakistan Department of Medicine&Gastroenterology Lifecare Hospital and Research CentrePeshawar 25000Khyber PakhtunkhwaPakistan Department of Hepatopancreatobiliary&Liver Transplant Bahria International HospitalLahore 54000Pakistan Department of Surgery Hepatopancreatobiliary&Liver TransplantDow University of Health SciencesKarachi 74800Pakistan Department of Gastroenterology Hepatology&NutritionPir Abdul Qadir Shah Jeelani Institute of Medical SciencesGambat 66020Pakistan Department of Oncology Dr.Ziauddin HospitalKarachi 74800Pakistan Department of Radiology Rehman Medical InstitutePeshawar 25000Pakistan Army Liver Transplant Unit Pak Emirates Military HospitalRawalpindi 46000Pakistan Department of Gastroenterology Sindh Institute of Urology and TransplantationKarachi 75500Pakistan Rashid Nursing Home and Cancer Clinic Rashid Nursing Home and Cancer ClinicRawalpindi 46000Pakistan Department of Gastroentero

A consensus meeting of national experts from all major national hepatobiliary centres in the country was held on May 26,2023,at the Pakistan Kidney and Liver Institute&Research Centre(PKLI&RC)after initial consultations with the *** Pakistan Society for the Study of Liver Diseases(PSSLD)and PKLI&RC jointly organised this *** effort was based on a comprehensive literature review to establish national practice guidelines for hilar cholangiocarcinoma(hCCA).The consensus was that hCCA is a complex disease and requires a multidisciplinary team approach to best manage these *** coordinated effort can minimise delays and give patients a chance for curative treatment and effective *** diagnostic and staging workup includes high-quality computed tomography,magnetic resonance imaging,and magnetic resonance *** cytology or biopsy utilizing endoscopic retrograde cholangiopancreatography is a mainstay for ***,histopathologic confirmation is not always required before *** ultrasound with fine needle aspiration of regional lymph nodes and positron emission tomography scan are valuable adjuncts for *** only curative treatment is the surgical resection of the biliary tree based on the Bismuth-Corlette *** patients with unresectable hCCA can be considered for liver *** chemotherapy should be offered to patients with a high risk of *** use of preoperative biliary drainage and the need for portal vein embolisation should be based on local multidisciplinary *** with acute cholangitis can be drained with endoscopic or percutaneous biliary *** chemotherapy with cisplatin and gemcitabine has shown improved survival in patients with irresectable and recurrent hCCA.

关键词： Hilar cholangiocarcinoma Bismuth-Corlette classification Memorial Sloan Kettering Cancer Centre Staging Preoperative biliary drainage Portal vein embolisation Surgical resection Hepatectomy