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Chinese Journal of Polymer Science 2010年第4期28卷 589-596页

作者： khalil faghihi Meisam Shabanian Atena Izadkhah Organic Polymer Chemistry Research Laboratory Department of ChemistryFaculty of ScienceArak UniversityArak 38156Iran

Five new optically active polyamides （PAs） 6a-6e were prepared by direct polycondensation reaction of 2-（1,3- isoindolinedione-2-yl）-glutaric acid 4 as a new chiral diacid with various aromatic diamines 5a-Se in a medium consisting of triphenyl phosphite （TPP）, calcium chloride, pyridine （Py） and N-methyl-2-pyrrolidone （NMP）. The polycondensation reaction produced a series of polyamids 6a-6e in quantitative yields with inherent viscosities of 0.26-0.39 dL/g. The resulting polymers were fully characterized by means of ^1H-NMR, FT-1R spectroscopy, elemental analysis, inherent viscosity and specific rotation. Thermal properties of these polymers were investigated using thermal gravimetric analysis （TGA） and differential thermal gravimetry （DTG）. Phthalimide rings as a bulky pendent group in the polymer chains disturb the interchain and intrachain interactions and make these PAs readily soluble in polar, aprotic solvents such as N,N-dimethyl acetamide （DMAc）, N,N-dimethyl formamide （DMF）, dimethyl sulfoxide （DMSO）, N-methyl-2-pyrrolidone （NMP） and sulfuric acid.

关键词： Polyamide Optically active polymers Thermally stable polymers

New thermally stable polyesters based on 2,5-pyridinedicarbonyl dichloride and aromatic diols:Synthesis and characterization

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Chinese Chemical Letters 2009年第7期20卷 885-888页

作者： Hossein Nasr Isfahani khalil faghihi Faculty of Chemistry Shahrood University of TechnologyShahroodIran Organic Polymer Chemistry Research Laboratory Department ofChemistryFaculty ofScienceArak UniversityArak 38156 Iran

Six new thermally stable polyesters （4a-f） were synthesized through the solution polycondensation reaction of 2,5-pyridine dicarbonyldichloride （2） with six aromatic diols in N,N＇-dimethyl acetamide （DMAc） solution and in the presence of pyridine as a base. The polycondensation reactions produce a series of new polyesters （4a-f） in high yields, and inherent viscosity between 0.30 and 0.55 dL/g. The resulting polyesters were characterized by elemental analysis, viscosity measurements, thermal gravimetric analysis （TGA and DTG）, solubility test, Fourier transform infrared （FT-IR） spectroscopy and gel permeation chromatography （GPC）. C 2009 khalil faghihi. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： High performance polymers Polyesters Pyridyl moiety

Synthesis and characterization of new optically active and organosoluble poly(ester-imide)s based on bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic diimide by direct polycondensation

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Science China Chemistry 2010年第4期53卷 898-904页

作者： faghihi khalil SHABANIAN Meisam HAJIBEYGI Mohsen Organic Polymer Chemistry Research Laboratory Department of ChemistryFaculty of ScienceArak University

New optically active poly(ester-imide)s PEIs were prepared from newly synthesized N,N′-(bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic)-bis-L-isoleucine diacid 4 via direct polycondensation with various aromatic diols in a system of tosyl chloride (TsCl), pyridine (Py), and N,N-dimethylformamide (DMF). The reactions with bicyclo TsCl were significantly promoted by controlling alcoholysis with diols, in the presence of catalytic amounts of DMF, to give a series of optically active PEIs, with good yield and moderate inherent viscosity ranging from 0.44 to 0.66 dL/g. The diacid 4 was synthesized by the condensation reaction of [2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride 1 with L-isoleucine 2 in acetic acid. All of these polymers were highly organosoluble in solvents such as N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dimethylsulfoxide (DMSO), and N-methyl-2-pyrrolidone (NMP) at room temperature. They were fully characterized by means of NMR spectroscopy, FTIR spectroscopy, gel permeation chromatography (GPC), elemental analyses, inherent viscosity, solubility test, and specific rotation, and thermal properties of the poly(ester-imide)s were investigated using TGA/DTG.

关键词： poly(ester-imide)s direct polycondensation optically active polymers L-isoleucine

Polyimide-silver nanocomposite containing phosphine oxide moieties in the main chain:Synthesis and properties

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Chinese Chemical Letters 2010年第11期21卷 1387-1390页

作者： khalil faghihi Mohsen Hajibeygi Meisam Shabanian Organic Polymer Research Laboratory Department of ChemistryFaculty of ScienceArak University

New flame-retardant polyimide-silver nanocomposite containing phosphine oxide moiety in the main chain was synthesized by a convenient ultraviolet irradiation technique.A precursor such as AgNO_3 was used as the source of the silver *** 6 as a source of polymer was synthesized by polycondensation reaction of bis（3-aminophenyl） phenyl phosphine oxide 4 with pyromellitic anhydride 5 in the presence of iso-quinoline as base and in m-cresol *** resulting composite film was characterized by FTIR spectroscopy,X-ray diffraction（XRD）,transmission electron microscopy（TEM）,thermogravimetry（TGA） and differential scanning calorimetry（DSC）.The average size of the nanometer Ag particles is about 10 *** temperature of 5 and 10%weight loss and also the char yield at 600℃of polyimide-silver nanocomposite 6a were higher than the pure PI 6.

关键词： Flame-retardant Polyimide-silver nanocomposite Phosphine oxide moiety

Magnetic and Heat Resistant Poly(imide-ether) Nanocomposites Derived from Methyl Rich 9H-xanthene: Synthesis and Characterization

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Chinese Journal of Polymer Science 2018年第7期36卷 822-834页

作者： khalil faghihi Hassan Moghanian Fatemeh Mozafari Meisam Shabanian Organic Polymer Chemistry Research Laboratory Department of Chemistry Faculty of Science Arak University Department of Chemistry Dezful Branch Islamic Azad University Faculty of Chemistry and Petrochemical Engineering Standard Research Institute (SRI)

In this study a new series of magnetic and heat resistant nanocomposites were prepared based on a highly soluble poly（imideether）（PIE） reinforced with two different types of magnetic nanoparticles via a solution intercalation technique. New PIE with good solubility and desired molar mass containing bulky xanthene rings and amide groups in the side chains was synthesized via thermal cyclization of the poly（amic acid） precursor, obtained from the reaction of a new diamine derived from 9H-xanthene and 4,4＇- oxydiphthalic dianhydride （ODPA）. Improved solubility was attributed to the presence of xanthene group and flexible ether linkage in the polyimide backbones that reduce the chain-chain interaction and enhance solubility by penetrating solvent molecules into the polyimide chains. Fe3O4 nanoparticles （MNPs） which synthesized from chemical co-precipitation route were coated with silica （SiO2）, sequentially with （3-aminopropyl）triethoxysilane and poly-melamine-terephthaldehyde （MNPs-PMT）, and then separately dispersed in the poly（amic acid） solutions and thermally imidized to form PIE/Fe3O4 and PIE/MNPs-PMT nanocomposites. The nanostructures and properties of the resultant materials were investigated using FTIR spectroscopy, X-ray diffraction （XRD）, field emission scanning electron microscopy （FE-SEM）, transmission electron microscopy （TEM）, vibrating sample magnetometer （VSM）, thermal gravimetric analysis （TGA） and differential scanning calorimetry （DSC）. The properties of the nanocomposites were strongly related to the dispersion and interaction between the nanoparticles and PIE matrix. The thermogravimetric analysis （TGA） results showed that the addition of MNPs-PMT nanoparticles resulted in a substantial increase in the thermal stability of the corresponding PIEN. The temperature at 10% weight loss （T10） was increased from 416℃to 428℃ for PIEN containing 3 wt% MNPs-PMT as compared to neat PIE, as well the char yield enhanced. Furthermore, the MNPs-PMT nanoparticles

关键词： Poly(imide-ether) Nanocomposite 9H-xanthene Magnetic nanoparticles

Thermally Stable and Organo-soluble Polyamides Containing Triazine Rings and Ether Linkages in the Main Chain: Synthesis and Characterization

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Chinese Journal of Polymer Science 2015年第1期33卷 109-117页

作者： Mohsen Hajibeygi khalil faghihi Majid Khodaei-Tehrani Zeinab Mirzakhanian Faculty of Chemistry Kharazmi University 15719-14911 Tehran Iran Department of Chemistry Faculty of Science Arak University Arak 38156-8-8349 Iran Department of Chemistry Arak Branch Islamic Azad UniversityArak Iran

In order to synthesize new polyamide（PA） 5 and copolyamides（Co PA） 7a-7d, a new-type of dicarboxylic acid containing triazine ring was successfully synthesized from 2,4-dichloro-6-methoxy-s-triazine 1 and 4-aminobenzoic acid. New polyamide 5 containing triazine moiety was prepared from 4,4＇-（6-methoxy-1,3,5-triazine-2,4-diyl）bis（azanediyl）dibenzoic acid 3 and 4,4′-diaminodiphenylether by direct polycondensation reaction. Then new series thermally stable copolyamides 7a-7d with high solubility in common organic solvents were synthesized from the direct polycondensation reaction of diacid 3 as a first monomer, aliphatic-aromatic diacids 6a-6d as second diacids and 4,4′-diaminodiphenylether. All of the above polymers were fully characterized by 1H-NMR and FTIR spectroscopy, elemental analysis（CHN）, inherent viscosity, solubility tests, gel permeation chromatography（GPC）, differential scanning calorimetry（DSC） and thermogravimetric analysis（TGA）. The resulted Co PAs 7a-7d have shown good inherent viscosities, solubility and thermal properties.

关键词： Polyamide Thermally stable Organo-soluble Polycondensation Triazine.

Effects of polyethyleneimine-functionalized MCM-41 on flame retardancy and thermal stability of polyvinyl alcohol

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Particuology 2015年第2期13卷 14-21页

作者： Meisam Shabanian Mehdi Khoobi Farideh Hemati Hossein Ali Khonakdar khalil faghihi Udo Wagenknecht Seyed esmaeil Sadat ebrahimia Abbas Shafiee Department of Medicinal Chemistry Faculty of Pharmacy and Pharmaceutical Sciences Research CenterTehran University of Medical Sciences Faculty of Chemistry and Petrochemical Engineering Standard Research Institute(SRI) Department of Chemistry Faculty of ScienceArak University Iran Polymer and Petrochemical Institute Leibniz-Institute of Polymer Research

Hyperbranched polyethylenimine （PEl）-functionalized mesoporous silica （MCM@PEI） was synthesized and used to produce poly（vinyl alcohol）（PVA） nanocomposites. The modified nanofiller was charac- terized with infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and N2 adsorption. When compared with pure meso- porous silica （MCM）, the MCM@PEI nanoparticles exhibited better dispersion in the PVA matrix. The effects of MCM@PEI on the thermal and flame properties of PVA nanocomposites were also studied. Improvement in the thermal properties was confirmed by enhanced thermal stability and char yield. Incorporation of MCM@PEI in PVA led to a significant drop in the heat release rate and the total heat release.

关键词： Nanocomposite PVA Nanofiller MCM-41

Secure Channel Estimation Using Norm Estimation Model for 5G Next Generation Wireless Networks

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Computers, Materials & Continua 2025年第1期82卷 1151-1169页

作者： khalil Ullah Song Jian Muhammad Naeem Ul Hassan Suliman Khan Mohammad Babar Arshad Ahmad Shafiq Ahmad Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650500China Department of Computer Science Abbottabad University of Science and TechnologyHavelianAbbottabad22500Pakistan Department of Computing and Electronics Engineering Middle East CollegeMuscat124Oman Department of CS&IT Pak-Austria Fachhochschule Institute of Applied Sciences and Technology MangHaripur22621Pakistan Industrial Engineering Department College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia

The emergence of next generation networks(NextG),including 5G and beyond,is reshaping the technological landscape of cellular and mobile *** networks are sufficiently scaled to interconnect billions of users and *** in academia and industry are focusing on technological advancements to achieve highspeed transmission,cell planning,and latency reduction to facilitate emerging applications such as virtual reality,the metaverse,smart cities,smart health,and autonomous *** continuously improves its network functionality to support these *** input multiple output(MIMO)technology offers spectral efficiency,dependability,and overall performance in *** article proposes a secure channel estimation technique in MIMO topology using a norm-estimation model to provide comprehensive insights into protecting NextG network components against adversarial *** technique aims to create long-lasting and secure NextG networks using this extended *** viability of MIMO applications and modern AI-driven methodologies to combat cybersecurity threats are explored in this ***,the proposed model demonstrates high performance in terms of reliability and accuracy,with a 20%reduction in the MalOut-RealOut-Diff metric compared to existing state-of-the-art techniques.

关键词： Next generation networks massive mimo communication network artificial intelligence 5G adversarial attacks channel estimation information security

Correction:Deep Learning-Enhanced Brain Tumor Prediction via Entropy-Coded BPSO in CIELAB Color Space

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Computers, Materials & Continua 2025年第1期82卷 1461-1461页

作者： Mudassir khalil Muhammad Imran Sharif Ahmed Naeem Muhammad Umar Chaudhry Hafiz Tayyab Rauf Adham E.Ragab Department of Computer Engineering Bahauddin Zakariya UniversityMultan60000Pakistan Department of Computer Science Kansas State UniversityManhattanKS 66506USA Department of Computer Science University of Management and TechnologyLahore54000Pakistan Independent Researcher BradfordBD80HSUK Industrial Engineering Department Collage of EngineeringKing Saud UniversityP.O.Box 800Riyadh11421Saudi Arabia

In the article“Deep Learning-Enhanced Brain Tumor Prediction via Entropy-Coded BPSO in CIELAB Color Space”by Mudassir khalil,Muhammad Imran Sharif,Ahmed Naeem,Muhammad Umar Chaudhry,Hafiz Tayyab Rauf,Adham *** Computers,Materials&Continua,2023,Vol.77,No.2,pp.2031–***:10.32604/cmc.2023.043687,URL:https://***/cmc/v77n2/54831,there was an error regarding the affiliation for the author Hafiz Tayyab *** of“Centre for Smart Systems,AI and Cybersecurity,Staffordshire University,Stoke-on-Trent,ST42DE,UK”,the affiliation should be“Independent Researcher,Bradford,BD80HS,UK”.

关键词： Deep Code CIELAB

Robust Stabilization of Non-minimum Phase Switched Nonlinear Systems with Uncertainty

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Journal of Systems Science & Complexity 2020年第2期33卷 289-311页

作者： khalil Jouili Laboratory of Advanced Systems Polytechnic School of Tunisia(EPT) B.P.7432078 MarsaTunisia

This paper investigates the problem of robust stabilization of a class of switched nonlinear system with uncertain dynamics where each subsystem represents a non-minimum *** authors first construct a stabilizing sliding mode controller for each subsystem to stabilize individually its own unstable internal ***,a switching strategy is introduced to select the most appropriate diffeomorphism through an infinity of *** conditions are specifically given for the exponential stability and the exponential upper bound of the trajectory of the switched subsystem,which guarantees the global asymptotical stability of the resulting switched ***,the proposed control approach can improvemore the transient state,compared to a feedback linearization based on only one *** studies illustrate the effectiveness of the suggested approach.

关键词： Exponential stability sliding mode control switching control uncertain non-minimum phase systems