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Covalent organic frameworks:Design and applications in electrochemical energy storage devices

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InfoMat 2022年第6期4卷 1-35页

作者： Shikai Jin omar Allam Seung Soon Jang Seung Woo Lee George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGeorgiaUSA Computational NanoBio Technology Laboratory School of Material Science and EngineeringGeorgia Institute of TechnologyAtlantaGeorgiaUSA

As an emerging class of crystalline organic material,covalent organic frameworks(COFs)possess uniform porosity,versatile functionality,and precise control over designated *** from the favorable charge and mass transport pathways offered by the porous framework,COFs can also exhibit designed reversible redox *** the past few years,their potential has attracted a great deal of attention for charge storage and transport applications in various electrochemical energy storage devices,and numerous design strategies have been proposed to enhance the corresponding electrochemical *** review summarizes the working principle and synthesis methods of COFs and discusses significant findings for supercapacitors and various rechargeable battery systems,emphasizing the representative design strategies and their underlying relationship with electrochemical *** addition,key advances achieved by computations are highlighted along with the challenges and prospects in this field.

关键词： covalent organic frameworks rechargeable batteries redox-active electrodes solid electrolyte supercapacitors

Naked Eye and Selective Detection of Copper(II) in Mixed Aqueous Media Using a Cellulose-based Support

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Chemical Research in Chinese Universities 2019年第4期35卷 598-603页

作者： FETTOUCHE Souad BOUKHRISS Aicha TAHIRI Mohamed CHERKAOUI omar BAZI Fathallaah GMOUH Said Laboratoire Recherche sur les Materiaux Textile(REN4TEX) Ecole Supeneure des Induseries de Textile et de L'habillement(ESITH)CasablancaBP 7731Maroc Laboratoire Hydrogeochimie et Bassin versant Faculte des Sciences Ain ChockUniversite Hassan IICasablancaB. P 5366Maroc Laboratore Chimie Analytique et Physico-chimie des Materiaux Faculte des Sciences Ben M'sik Universitie Hassan II CasablancaBP 150Macro Laboratoire d'lngeniene et Materiaux(LIMAT) Faculte des Sciences Ben MsikUniv er site Hassan IICasablanceBP 150Maroc

A new colorimetric sensor based-azo dye for Cu^2+ detection was synthesized and characterized by FTIR and NMR spectroscopies. The results showed that the azo dye had a high selective and sensitive recognition toward Cu^2+. The solution containing the sensor changed color from pink to pale yellow with a hypsochromic shift in the presence of Cu^2+. The sensor selectivity and sensitivity toward Cu^2+ ions were investigated by colorimetry and UV-Vis spectroscopy. For practical applications, a cellulosic textile test strip for high-selectivity detection of Cu^2+ ions in aqueous solution was developed using the synthesized azo dye as chromogenic chemosensor molecule, while using a solid cellulose textile as a substrate. As a result, a spectacular color change of the test strip was observed do pending on the amount of copper ions in contact with the strip, which allows an estimation of Cu^2+ concentration by naked eye.

关键词： Copper(II) ions detection Azo dye Chromogenic chemosensor Cellulose-based probe

Epidemiology of inflammatory bowel disease in racial and ethnic migrant groups

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World Journal of Gastroenterology 2018年第3期24卷 424-437页

作者： Ravi Misra omar Faiz Pia Munkholm Johan Burisch Naila Arebi Department of Gastroenterology St.Marks Academic Institute Surgical Epidemiology Trials and Outcome CentreSt.Marks Academic Institute Department of Gastroen-terology North Zealand University Hospital

AIM To summarise the current literature and define patterns of disease in migrant and racial *** A structured key word search in Ovid Medline and EMBASE was undertaken in accordance with PRISMA guidelines. Studies on incidence, prevalence and disease phenotype of migrants and races compared with indigenous groups were eligible for inclusion. RESULTS Thirty-three studies met the inclusion criteria. Individual studies showed significant differences in incidence, prevalence and disease phenotype between migrants or race and indigenous groups. Pooled analysis could only be undertaken for incidence studies on South Asians where there was significant heterogeneity between the studies [95% for ulcerative colitis(UC), 83% for Crohn's disease(CD)]. The difference between incidence rates was not significant with a rate ratio South Asian: Caucasian of 0.78(95%CI: 0.22-2.78) for CD and 1.39(95%CI: 0.84-2.32) for UC. South Asians showed consistently higher incidence and more extensive UC than the indigenous population in five countries. A similar pattern was observed for Hispanics in the United States. Bangladeshis and African Americans showed an increased risk of CD with perianal disease. CONCLUSION This review suggests that migration and race influence the risk of developing inflammatory bowel disease. This may be due to different inherent responses upon exposure to an environmental trigger in the adopted country. Further prospective studies on homogenous migrant populations are needed to validate these observations, with a parallel arm for in-depth investigation of putative drivers.

关键词： Epidemiology Ethnicity Migration

Phase modification and dielectric properties of a cullet–paper ash–kaolin clay-based ceramic

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International Journal of Minerals,Metallurgy and Materials 2018年第3期25卷 350-356页

作者： K.A.Samah M.R.Sahar M.Yusop M.F.omar Advance Optical Material Research Group Department of Physics Faculty of Science Universiti Teknologi Malaysia

Novel ceramics from waste material made of(x) paper ash–(80-x) cullet–20 kaolin clay(10 wt% ≤ x ≤ 30 wt%) were successfully synthesized using a conventional solid-state reaction technique. Energy-dispersive X-ray analysis confirmed the presence of Si, Ca, Al, and Fe in the waste material for preparing these ceramics. The influence of the cullet content on the phase structures and the dielectric properties of these ceramics were systematically investigated. The impedance spectra were verified in the range from 1 Hz to 10 MHz at room temperature. The phase of the ceramics was found to primarily consist of wollastonite(CaSiO_3), along with minor phases of γ-dicalcium silicate(Ca_2SiO_4) and quartz(SiO_2). The sample with a cullet content of 55 wt% possessed the optimum wollastonite structure and exhibited good dielectric properties. An increase of the cullet content beyond 55 wt% resulted in a structural change from wollastonite to dicalcium silicate, a decrease in dielectric constant, and an increase in dielectric loss. All experimental results suggested that these novel ceramics from waste are applicable for electronic devices.

关键词： ceramics cullet glass paper ash wollastonite structural properties dielectric properties

Chemical composition of Mentha suaveolens and Pinus halepensis essential oils and their antibacterial and antioxidant activities

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Asian Pacific Journal of Tropical Medicine 2019年第3期12卷 117-122页

作者： Abdelhakim Bouyahya omar Belmehdi Jamal Abrini Nadia Dakka Youssef Bakri Laboratory of Human Pathologies Biology Department of BiologyFaculty of Sciencesand Genomic Center of Human PathologiesFaculty of Medicine and PharmacyMohammed V University in Rabat Biology and Health Laboratory Department of BiologyFaculty of SciencesAbdelmalek Essaadi University

Objective: To determin the chemical compounds of Mentha suaveolens(M. suaveolens) and Pinus halepensis(P. halepensis) essential oils(Eos) and evaluate their antioxidant and antibacterial activities. Methods: The chemical composition of P. halepensis and M. suaveolens EOs was determined by GC-MS analysis. The antioxidant activity was evaluated using DPPH,ABTS and FRAP assays. The antibacterial effect was tested against 6 bacterial strains using the well diffusion method and micro-dilution assay. Results: The major components of P. halepensis EOs were β-caryophyllene(28.04%),myrcene(23.81%) and α-pinene(12.02%). However,piperitenone oxid(56.28%),piperitenone(11.64%) and pulegone(6.16%) were the major components of M. suaveolens EOs. M. suaveolens EOs showed remarkable antioxidant activities compared with P. halepensis EOs,showing antioxidant capacity values of IC50=(64.76±2.24) μg/mL,IC50=(82.73±3.34) μg/mL,and IC50=(93.35±4.45) μg/mL,revealed by DPPH,ABTS and FRAP assays,respectively. However,P. halepensis EOs showed interesting antibacterial effects against all bacterial strains. The most sensible strains to P. halepensis EOs were Staphylococcus aureus [(34.00±0.50) mm],Listeria monocytogenes [(31.00±1.50)] mm and Proteus mirabilis [(29.00±2.25)mm]. Furthermore,the lowest minimal inhibitory concentration(MIC) and minimal bactericidal concentration(MBC) values were revealed by P. halepensis EOs against Staphylococcus aureus [MIC=MBC=0.125%(v/v)] and Listeria monocytogenes [MIC=MBC=0.25%(v/v)]. Conclusions: P. halepensis and M. suaveolens EOs contain bioactive compounds that could have potential applications against bacterial infections and oxidative stress related diseases as well as for food conservation. However,further investigations are necessary to isolate and investigate the action mechanisms of these bioactive compounds.

关键词： Mentha suaveolens Pinus halepensis Essential oil Antioxidant effect Antibacterial activity

An Optimized Data Fusion Paradigm for WSN Based on Neural Networks

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Computers, Materials & Continua 2021年第10期69卷 1097-1108页

作者： Moath Alsafasfeh Zaid A.Arida omar A.Saraereh Qais Alsafasfeh Salem Alemaishat Department of Computer Engineering Al-Hussein Bin Talal UniversityMa’anJordan School of Computing and Informatics Al Hussein Technical UniversityAmman11831Jordan Department of Electrical Engineering Hashemite UniversityZarqa13133Jordan Department of Electrical Power and Mechatronics Tafila Technical UniversityTafilaJordan School of Computing and Informatics Al-Hussein Technical University KHBPAmman11855Jordan

Wireless sensor networks(WSNs)have gotten a lot of attention as useful tools for gathering *** energy problem has been a fundamental constraint and challenge faced by many WSN applications due to the size and cost constraints of the sensor *** paper proposed a data fusion model based on the back propagation neural network(BPNN)model to address the problem of a large number of invalid or redundant *** three layeredbased BPNNs and a TEEN threshold,the proposed model describes the cluster structure and filters out unnecessary *** the information transmission process,the neural network’s output function is used to deal with a large amount of sensing data,where the feature value of sensing data is extracted and transmitted to the sink *** terms of life cycle,data traffic,and network use,simulation results show that the proposed data fusion model outperforms the traditional TEEN *** a result,the proposed scheme increases the life cycle of the network thereby lowering energy usage and traffic.

关键词： WSN clustering data collection neural networks

Numerical Investigation and Optimization of a Flat Plate Solar Collector Operating with Cu/CuO/Al_(2)O_(3)–Water Nanofluids

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Transactions of Tianjin University 2021年第1期27卷 64-76页

作者： Youssef Belkassmi Kamal Gueraoui Lahoucine El maimouni Najem Hassanain omar Tata ERMAM Polydisciplinary Faculty of OuarzazateIbn Zohr UniversityBox 638OuarzazateMorocco MSME Faculty of SciencesMohammed-V UniversityRabatMorocco Group of Semiconductors and Environmental Sensor Technologies-Energy Research Center Faculty of ScienceMohammed-V UniversityB.P.1014RabatMorocco GEMS Laboratory ENSAIbn Zohr UniversityB.P.1136AgadirMorocco

Nanofluids are a potential alternative to significantly improving the performance of heat transfer applications. In this work, a numerical analysis to examine the eff ect of dispersing copper(Cu), copper oxide(CuO), and aluminum(Al2O3) nanoparticles in pure water on the performance of a flat plate solar collector(FPSC) and a numerical model was proposed. The influence of the nanofluid type on the thermal efficiency was critically investigated and discussed. The eff ect of the mass flow rate on the performance was also analyzed and discussed. Based on correlations of the thermophysical properties of nanofluids, a sensitivity analysis was used to analyze the impact of the nanoparticles on the base fluid. The results indicate that the performance of the FPSC with Cu/water nanofluid was better than that of FPSCs using CuO/water or Al2O3/water nanofluids. When the mass flow rate of the nanofluids was 8.0 L/min, the efficiency of the FPSC was much greater than those at the flow rates of 5.0 L/min and 2.0 L/min. Mean enhancements in thermal efficiency of 4.44%, 4.27%, and 4.21% were observed when 2.0 L/min was applied using Cu/water, Cu O/water, and Al2O3/water nanofluids, respectively. Improvements in thermal efficiency of 2.76%, 2.53%, and 2.47% occurred when 8.0 L/min was applied.

关键词： Flat plate solar collector Solar energy Thermal efficiency Nanofluids Al_2O_3/water Cu/water CuO/water

Far and Near Optimization:A New Simple and Effective Metaphor-LessOptimization Algorithm for Solving Engineering Applications

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Computer Modeling in Engineering & Sciences 2024年第11期141卷 1725-1808页

作者： Tareq Hamadneh Khalid Kaabneh omar Alssayed Kei Eguchi Zeinab Monrazeri Mohammad Dehghani Department of Matematics Al Zaytoonah University of JordanAmman11733Jordan Jadara Research Center Jadara UniversityIrbid21110Jordan Faculty of Information Technology Al-Ahliyya Amman UniversityAmman19328Jordan Department of Mathematics Faculty of ScienceThe Hashemite UniversityP.O.Box 330127Zarqa13133Jordan Department of Information Electronics Fukuoka Institute of TechnologyFukuoka811-0295Japan Department of Electrical and Electronics Engineering Shiraz University of TechnologyShiraz***Iran

In this article,a novel metaheuristic technique named Far and Near Optimization(FNO)is introduced,offeringversatile applications across various scientific domains for optimization *** core concept behind FNO lies inintegrating global and local search methodologies to update the algorithm population within the problem-solvingspace based on moving each member to the farthest and nearest member to *** paper delineates the theoryof FNO,presenting a mathematical model in two phases:(i)exploration based on the simulation of the movementof a population member towards the farthest member from itself and(ii)exploitation based on simulating themovement of a population member towards the nearest member from ***’s efficacy in tackling optimizationchallenges is assessed through its handling of the CEC 2017 test suite across problem dimensions of 10,30,50,and 100,as well as to address CEC *** optimization results underscore FNO’s adeptness in exploration,exploitation,and maintaining a balance between them throughout the search process to yield viable *** analysis against twelve established metaheuristic algorithms reveals FNO’s superior *** findings indicate FNO’s outperformance of competitor algorithms,securing the top rank as the mosteffective optimizer across a majority of benchmark ***,the outcomes derived by employing FNOon twenty-two constrained optimization challenges from the CEC 2011 test suite,alongside four engineering designdilemmas,showcase the effectiveness of the suggested method in tackling real-world scenarios.

关键词： Optimization stochastic method far near metaheuristic algorithm exploration exploitation

Bone marrow-derived mesenchymal stem cells ameliorate sodium nitrite-induced hypoxic brain injury in a rat model

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Neural Regeneration Research 2017年第12期12卷 1990-1999页

作者： Elham H.A.Ali omar A.Ahmed-Farid Amany A.E.Osman Faculty of Women for Art Sciences and Education Ain Shams University Cairo Egypt National Organization for Drug Control and Research (NODCAR) Giza Egypt

Sodium nitrite（Na NO2） is an inorganic salt used broadly in chemical industry. Na NO2 is highly reactive with hemoglobin causing hypoxia. Mesenchymal stem cells（MSCs） are capable of differentiating into a variety of tissue specific cells and MSC therapy is a potential method for improving brain functions. This work aims to investigate the possible therapeutic role of bone marrow-derived MSCs against Na NO2 induced hypoxic brain injury. Rats were divided into control group（treated for 3 or 6 weeks）, hypoxic（HP） group（subcutaneous injection of 35 mg/kg Na NO2 for 3 weeks to induce hypoxic brain injury）, HP recovery groups N-2 w R and N-3 w R（treated with the same dose of Na NO2 for 2 and 3 weeks respectively, followed by 4-week or 3-week self-recovery respectively）, and MSCs treated groups N-2 w SC and N-3 w SC（treated with the same dose of Na NO2 for 2 and 3 weeks respectively, followed by one injection of 2 × 106 MSCs via the tail vein in combination with 4 week self-recovery or intravenous injection of Na NO2 for 1 week in combination with 3 week self-recovery）. The levels of neurotransmitters（norepinephrine, dopamine, serotonin）, energy substances（adenosine monophosphate, adenosine diphosphate, adenosine triphosphate）, and oxidative stress markers（malondialdehyde, nitric oxide, 8-hydroxy-2′-deoxyguanosine, glutathione reduced form, and oxidized glutathione） in the frontal cortex and midbrain were measured using high performance liquid chromatography. At the same time, hematoxylin-eosin staining was performed to observe the pathological change of the injured brain tissue. Compared with HP group, pathological change of brain tissue was milder, the levels of malondialdehyde, nitric oxide, oxidized glutathione, 8-hydroxy-2′-deoxyguanosine, norepinephrine, serotonin, glutathione reduced form, and adenosine triphosphate in the frontal cortex and midbrain were significantly decreased, and glutathione reduced form/oxidized glutathione and adenosine monophosphate/adenosine

关键词： nerve regeneration hypoxia bone marrow-derived mesenchymal stem cells sodium nitrite monoamine neurotransmitter cell energy neural regeneration