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Strength and Wear Behavior of Mg Alloy AE42 Reinforced with Carbon Short Fibers

Acta Metallurgica Sinica(English Letters) 2019年第1期32卷 31-40页

作者： Sabbah Ataya naser a.alsaleh Mohamed M.El-Sayed Seleman Metallurgical and Materials Engineering Department Faculty of Petroleum and Mining Engineering Suez University Department of Mechanical Engineering College of Engineering Al Imam Mohammad Ibn Saud University

In addition to the advantage of the lightweight of magnesium alloys, magnesium composites have moderate strength and elastic modulus. The proposed application of magnesium composites as diesel truck pistons makes it necessary to assess their wear performance. Little research data have been discussed on wear behavior of Mg alloy AE42 matrix and its composites. Thus, this paper reports wear behavior of magnesium alloy AE42(Mg–Al–Mn—RE; rare earth) and its composite AE42-C, which contains 23 vol% of randomly oriented carbon short fibers. Materials characterization, including density measurements, hardness testing, microstructures investigation, and compression testing at temperatures of 25, 150,and 300 °C, were conducted. Wear tests were performed under various loads and sliding distances. Wear mechanisms were also proposed based on the examination of worn surfaces using optical microscopy and scanning electron microscopy equipped with EDX(energy-dispersive X-ray spectrometry) analysis system. The hardness of AE42-23 vol% C composite is twice the hardness of the Mg matrix alloy AE42. Significant improvements to yield stress and compressive strength at temperatures of 25, 150, and 300 °C of the composite versus the AE42 alloy are achieved. Wear resistance of the composite is improved considerably versus that of the Mg alloy AE42 at the various sliding distances. Smearing of graphite on the worn surface produces a lubricating film that delays change from mild to severe wear of the composite, especially at high loads. EDX analysis of the worn surface shows oxidation of the matrix alloy at higher wear loads, and this mechanism decreases in the presence of carbon fibers under the same loads. Abrasive wear, oxidation, and plastic deformation are the dominant wear mechanisms for the alloy matrix AE42, whereas mainly abrasive wear is the wear mechanism of AE42-23 vol% C composite under the proposed testing conditions.

关键词： Magnesium composites Carbon short fibers Compressive strength Wear resistance Wear mechanisms

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Fire resistance evaluation through synthetic fire tests and generative adversarial networks

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 587-614页

作者： AybikeÖzyükselÇiftçioğlua M.Z.naser Department of Civil Engineering Manisa Celal Bayar University45140Türkiye School of Civil&Environmental Engineering and Earth Sciences(SCEEES) Clemson UniversityClemsonSC 29631USA Artificial Intelligence Research Institute for Science and Engineering(AIRISE) Clemson UniversityClemsonSC 29631USA

This paper introduces a machine learning approach to address the challenge of limited data resulting from costly and time-consuming fire experiments by enlarging small fire test data sets and predicting the fire resistance of reinforced concrete *** approach begins by creating deep learning models,namely generative adversarial networks and variational autoencoders,to learn the spatial distribution of real fire *** then use these models to generate synthetic tabular samples that closely resemble realistic fire resistance values for reinforced concrete *** generated data are employed to train state-of-the-art machine learning techniques,including Extreme Gradient Boost,Light Gradient Boosting Machine,Categorical Boosting Algorithm,Support Vector Regression,Random Forest,Decision Tree,Multiple Linear Regression,Polynomial Regression,Support Vector Machine,Kernel Support Vector Machine,Naive Bayes,and K-Nearest Neighbors,which can predict the fire resistance of the columns through regression and *** learning analyses achieved highly accurate predictions of fire resistance values,outperforming traditional models that relied solely on limited experimental *** study highlights the potential for using machine learning and deep learning analyses to revolutionize the field of structural engineering by improving the accuracy and efficiency of fire resistance evaluations while reducing the reliance on costly and time-consuming experiments.

关键词： deep learning fire resistance generative adversarial networks machine learning

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Rice Husk at a Glance:From Agro-Industrial to Modern Applications

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Rice science 2024年第1期31卷 14-32页

作者： Masoumeh KORDI naser FARROKHI Martin I.PECH-CANUL Asadollah AHMADIKHAH Department of Cell&Molecular Biology Faculty of Life Sciences and BiotechnologyShahid Beheshti UniversityTehran ***Iran 1062 Metallurgical Industry Avenue Industrial Park Saltillo-Ramos ArizpeRamos ArizpeCoahuila 25900Mexico

Excessive waste production has led to the concept of a circular bioeconomy to deliver valuable by-products and improve environmental *** annual worldwide rice production accounts for more than 750 million tons of grain and 150 million tons of *** husk(RH)contains valuable biomaterials with extensive applications in various *** proportions of each component depend primarily on rice genotype,soil chemistry,and climatic *** and its derivatives,including ash,biochar,hydrochar,and activated carbon have been placed foreground of applications in agriculture and other *** the investigation on RH’s compositions,microstructures,and by-products has been done copiously,owing to its unique features,it is still an open-ended area with enormous scope for innovation,research,and ***,we reviewed the latest applications of RH and its derivatives,including fuel and other energy resources,construction materials,pharmacy,medicine,and nanobiotechnology to keep this versatile biomaterial in the spotlight.

关键词： circular bioeconomy rice husk activated carbon rice husk ash rice husk biochar rice husk hydrochar rice husk application

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Tilt Angle Optimality Criteria for Stand Alone PV Systems

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Journal of Power and Energy Engineering 2024年第3期12卷 1-18页

作者： Mohammad Abu-naser Faculty of Engineering and Technology Philadelphia University Amman Jordan

The conventional approach to optimizing tilt angles for fixed solar panels aims to maximize energy generation over the entire year. However, in the context of a supply controlled electric grid, where solar energy availability varies, this criterion may not be optimal. This study explores two alternative optimization criteria focused on maximizing baseload supply potential and minimizing required storage capacity to address seasonality in energy generation. The optimal tilt angles determined for these criteria differed significantly from the standard approach. This research highlights additional factors crucial for designing solar power systems beyond gross energy generation, essential for the global transition towards a fully renewable energy-based electric grid in the future.

关键词： Electric Grid Fixed Solar Panels Optimal PV Tilt Angle Seasonal Solar Variability Renewable Energy Supply-Demand Balance

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Cardiovascular risk factors affecting COVID-19 outcomes at a tertiary referral hospital in northwest Iran: A prospective cohort study

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Journal of Acute Disease 2024年第1期13卷 8-13页

作者： Mahsa Behnemoon Mojdeh Mehrno naser Gharebaghi Milad Hamdi Department of Cardiology School of MedicineUrmia University of Medical ScienceUrmiaIran Medical Center Urmia University of Medical ScienceUrmiaIran Department of Dermatology and Infectious Disease School of MedicineUrmia University of Medical ScienceUrmiaIran

Objective:To investigate cardiovascular risk factors affecting COVID-19 outcomes in a tertiary referral ***:This prospective cohort study analyzed 269 participants with *** primary outcomes were ICU admission,prolonged hospital stay duration,and in-hospital *** secondary outcomes included death,chronic symptoms,and NYHA functional class during follow-up ***:A total of 412 patients with COVID-19 symptoms were enrolled in the study,and out of which 269 patients had complete medical records and positive SARS-CoV-2 PCR test results,fulfilling the study criteria were *** patients were divided into two groups,with cardiovascular comorbidities(group A,n=122),such as established cardiovascular disease,diabetes mellitus,and hypertension,and without cardiovascular comorbidities(group B,n=147).Binary logistic regression analysis showed that patients with underlying hypertension,diabetes,and established cardiovascular disease had a 1.55(95%CI:1.28-2.26),1.62(95%CI:1.34-2.13),and 1.63(95%CI:1.07-5.34)-fold risk of mortality,respectively in the adjusted ***:Hospitalized COVID-19 patients with predisposing cardiovascular risk factors are more susceptible to develop worse *** attention should be paid to the management and follow-up of these patients.

关键词： COVID-19 Outcome Cardiovascular Chronic symptoms Diabetes mellitus Hypertension

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Pediatric and adult liver transplantation in Bahrain: The experiences in a country with no available liver transplant facilities

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World Journal of Transplantation 2024年第1期14卷 96-111页

作者： Hasan M Isa Fatema A Alkharsi Jawad K Khamis Sawsan A Hasan Zainab A naser Zainab N Mohamed Afaf M Mohamed Shaikha A Altamimi Department of Pediatrics Salmaniya Medical ComplexManama 26671Bahrain Department of Pediatrics Arabian Gulf UniversityManama 26671Bahrain Department of Medicine Salmaniya Medical ComplexManama 26671Bahrain Public Health Directorate Ministry of HealthManama 26671Bahrain The Overseas Office Supreme Committee for Treatment AbroadMinistry of HealthManama 26671Bahrain

BACKGROUND Liver transplantation(LT)is a life-saving procedure for patients with end-stage liver disease and has become the standard and most effective treatment method for these *** are many indications for LT that vary between countries and *** outcome of LT depends on the available facilities and surgical expertise,as well as the types of liver graft donors *** To assess the clinical characteristics of patients from Bahrain who underwent LT overseas,and analyze factors affecting their *** In this retrospective cohort study,we reviewed the medical records and overseas committee registry information of all pediatric and adult patients who were sent overseas to undergo LT by the Pediatric and Medical Departments of Salmaniya Medical Complex and Bahrain Defence Force Hospital via the Overseas Treatment Office,Ministry of Health,Kingdom of Bahrain,between 1997 and *** data,LT indication,donor-recipient relationship,overseas LT center,graft type,post-LT medications,and LT complications,were *** measured included the overall and 5-year LT survival ***’s exact,Pearsonχ2,and Mann-Whitney U tests were used to compare the pediatric and the adults’group in terms of clinical characteristics,donor-recipient relationship,medication,complications,and *** analysis was estimated via the Kaplan-Meier’s *** and multivariate analyses were used to detect predictors of *** Of the 208 eligible patients,170(81.7%)were sent overseas to undergo LT while 38(18.3%)remained on the waiting *** the 170 patients,167(80.3%)underwent LT and were included in the *** majority of the patients were Bahraini(91.0%),and most were males(57.5%).One-hundred-and-twenty(71.8%)were adults and 47(28.3%)were *** median age at transplant was 50.0[interquartile range(IQR):14.9–58.4]*** main indication for pediatric LT was biliary atresia(31.9%),while that of adult LT was

关键词： Overseas liver transplantation End-stage liver disease Liver transplant facilities Liver donor Biliary atresia Hepatitis C

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Analyzing uncertainties involved in estimating collapse risk with and without considering uncertainty probability distribution parameters

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Earthquake Engineering and Engineering Vibration 2022年第1期21卷 101-116页

作者： Mohammad Amin Bayari naser Shabakhty Esmaeel Izadi Zaman Abadi Department of Civil Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran School of Civil Engineering Iran University of Science and TechnologyTehran 16844Iran

In the present study,modified Ibarra,Medina and Krawinkler moment-rotation parameters are used for modeling the uncertainties in concrete moment frame *** of model parameters in a component and between two structural components were considered to analyze these *** the first step,the structural collapse responses were obtained by producing 281 samples for the uncertainties using the Latin hypercube sampling(LHS)method,considering the probability distribution of the uncertainties and performing incremental dynamic *** the second step,281 new samples were produced for the uncertainties by the central composite design(CCD)method without considering the probability distribution of the uncertainties and calculating the structural collapse ***,using the response surface method(RSM)and artificial neural network(ANN)for the two simulation modes,structural collapse responses were *** results indicated that the collapse responses at levels of 0 to 100%obtained from the two simulations have a high correlation coefficient of 98%.This suggests that random variables can be simulated without considering the probability distribution of uncertainties,by performing uncertainty analysis to determine structural collapse responses.

关键词： uncertainty analysis collapse response artificial neural network response surface method

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Protective efficacy of dark chocolate in letrozole-induced ovary toxicity model rats: hormonal, biochemical, and histopathological investigation

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Journal of Traditional Chinese Medicine 2022年第5期42卷 741-748页

作者： naser Mirazi Sheida Hesami Alireza Nourian Abdolkarim Hosseini Department of Biology Faculty of Basic SciencesBu-Ali Sina UniversityHamedan ***Iran Department of Pathobiology Faculty of Veterinary ScienceBu-Ali Sina UniversityHamedan ***Iran Department of Animal Sciences and Biotechnology Faculty of Life Sciences and BiotechnologyShahid Beheshti UniversityTehran ***Iran

OBJECTIVE: To assess the protective effect of dark chocolate(DC) on the letrozole-induced rat model of polycystic ovary syndrome(PCOS). METHODS: In this experimental study, 32 female Wistar rats, weighing(200 ± 20) g, were randomly categorized into 4 groups including control, letrozole(1 mg·kg-1·d-1), metformin(500 mg·kg-1·d-1) along with letrozole, and DC(500 mg·kg-1·d-1) along with letrozole for 28 d by oral gavage. Twenty-four hours after the last supplementation, direct blood sampling was taken from the heart to obtain blood serum for evaluation of sex hormones and gonadotropins, oxidative parameters, inflammatory cytokines, and ovarian tissue was examined for histology. RESULTS: The DC treatment significantly improved PCOS signs, as demonstrated by the significant restoration of ovarian morphology and physiological functions as compared with the letrozole group. DC treatment also decreased ovarian interleukin-1β and tumor necrosis factor-α levels and improved total oxidative/antioxidative status as compared with the letrozole group. CONCLUSIONS: Treating the animals with DC could alleviate the PCOS symptoms and reduced the toxic effects of letrozole in the ovary. This effect may mediate through antioxidant and antiinflammatory properties.

关键词： chocolate letrozole metformin polycystic ovary syndrome antioxidants anti-inflammatory agents

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Plasma-Assisted Antimicrobial Finishing of Textiles: A Review

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Engineering 2022年第5期8卷 145-163页

作者： Maryam Naebe Abu naser Md Ahsanul Haque Aminoddin Haji Deakin University Institute for Frontier MaterialsGeelongVIC 3216Australia Textile Engineering Department Yazd UniversityYazd 89138-75639Iran

Owing to the ongoing pandemic,the importance of and demand for antimicrobial textiles have reached new *** addition to being used for medical purposes,antimicrobial textiles could be a self-defense entity against microbes for the general *** textiles are widely used,they can effectively be used to prevent the spread of microbes *** conventional antibacterial finishing process of textiles is the wet treatment method using either the pad–dry–cure or exhaustion ***,the textile wet treatment industries are major contributors to worldwide pollution,which is extremely *** the current and near-future high demand,it is imperative to include plasma in antimi-crobial finishing to achieve high efficiency in production,while retaining a safe ***,this paper reviews the rationale of plasma use in textile antimicrobial finishing through a critical analysis of recent studies and emphasizes the types and mechanisms of plasma techniques available for application.

关键词： Plasma Grafting Polymerization Sputtering Nanomaterials Antimicrobial

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Carbon Isotope Stratigraphy of the Uppermost Aptian-Lower Cenomanian Strata from the Lut Block,East Iran

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Journal of Earth Science 2023年第6期34卷 1793-1799页

作者： Javad Sharifi Seyed naser Raisossadat Maryam Mortazavi Mehrizi Maryam Motamedalshariati Department of Geology Faculty of ScienceUniversity of BirjandBirjandIran Earth Sciences Research Group University of BirjandBirjandIran

The Mid-Cretaceous interval has been recognized as a crucial period in Earth’s history,and a number of studies on Neo-Tethyan successions illustrate intense evolutions in the nature of Mid-Cretaceous ocean chemistry,sea level,and marine faunal ***,much less investigations have been conducted in the Sistan Ocean,in the eastern ***,the Nimbolook Section(Lut Block,central Iran)has provided an opportunity to address these shortcomings and provide a better understanding of the paleoenvironmental changes in this *** biostratigraphic analysis and age interpretation of the Nimbolook Section have been performed in earlier investigations by means of planktonic foraminifera,ammonites and calcareous *** provides a reliable age framework for the chemostratigraphic *** the Nimbolook Section,the δ^(13)C stratigraphy was carried out on a total of 41 samples,which ranged between -3.26‰and 2.86‰ with an average of 1.09‰(standard deviation=1.15‰),and expanded within the upper Aptian to lower Cenomanian ***,there is a prominent negative shift at the base of the section,accompanied by episodes of sea-level ***,according to the age-diagnostic calcareous nannofossils records,this carbon isotope negative shift(0.88‰ to -3.26‰)straddle between late Aptian and early Albian ***,these new chemostratigraphic observations could be interpreted as being the coeval data from the reference well-studied successions in the other parts of the world,tentatively reflecting the oceanic anoxic event(OAE)1b.

关键词： Aptian-Albian Lut Block carbon isotope stratigraphy geochemistry Iran

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