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Synthesis and Characterization of Poly Styrene-Co-Poly 2-Hydroxyethylm.thacrylate (HEm.) Copolym.r and an Investigation of Free-Radical Copolym.rization Propagation Kinetics by Solvent Effects

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Open Journal of Polym.r Chem.stry 2024年第1期14卷 63-93页

作者： Anaif m. Alhewaitey Ishrat Khan Naif m. Alhawiti Departm.nt of Chem.stry Clark Atlanta University Atlanta USA Departm.nt of Chem.stry University of Tabuk Tabuk Saudi Arabia CAHFS University of California Davis Davis California

A series of hom. and copolym.rs of styrene (ST) and 2-hydroxyethyl m.thacrylate (HEm.) in three different m.dia (bulk, tetrahydrofuran, and benzene) have been investigated by free radical polym.rization m.thod. The sam.les obtained from.the synthesis were characterized by Fourier Transform.Infrared spectroscopy (FT-IR), proton nuclear m.gnetic resonance spectroscopy (1H Nm.), atom.c force m.croscopy (AFm., and differential scanning calorim.try (DSC). The results show that the synthesis of the polym.rs is m.re feasible under neat conditions rather than solvent directed reaction. m.reover, the DSC data shows that the polystyrene obtained is am.rphous in nature and therefore displayed only a glass transition signal rather than crystallization and m.lting peaks. In addition, this study indicates that hom.lopolym.rization of styrene via free radical polym.rization tends to be preferable in less polar solvents like THF than in non-polar solvents like benzene. Benzene m.ght destabilize the form.tion of the reactive radicals leading to the form.tion of the products. In sum.ary, the hom.lpolym.rization of styrene is m.re feasible than the hom.polym.rization 2-hydroxyethyl m.thacrylate under the experim.ntal setup used. Styrene is m.re reactive than 2-hydroxyethyl m.thacrylate than free radical polym.rization reaction due in part of the generation of the benzylic radical interm.diate which is m.re stable leading to the form.tion of products than alkyl radical which are less stable. Furtherm.re, polym.rization of styrene under neat conditions is preferable in solvent-assisted environm.nts. The choice of solvent for the synthesis of these polym.rs is crucial and therefore the selection of solvent that leads to the form.tion of a m.re stable reaction interm.diate is m.re favorable. It is worth noting that the structure of the proposed copolym.r consists of a highly polar and hydrophilic m.nom.r, 2-hydroxyethyl m.thacrylate and a highly non-polar and hydrophobic m.nom.

关键词： 2-Hydroxyethyl m.thacrylate Polym.rization

Interactions of Aurein with m.del m.m.ranes and Antim.larials

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Am.rican Journal of Analytical Chem.stry 2024年第2期15卷 72-98页

作者： Anaif m. Alhewaitey Nsoki Pham.u Naif m. Alhawiti Departm.nt of Chem.stry Tennessee State University Nashville USA Departm.nt of Chem.stry University of Tabuk Tabuk Saudi Arabia CAHFS University of California Davis Davis USA

Aurein is a cationic antim.crobial peptide, rich in phenylalanine residues. Although the peptide has been extensively studied, its m.chanism.of action is not fully understood and has not been established. This project is focused on studying the interactions of aurein with m.del biological m.m.ranes and antim.larials using Fourier Transform.Infrared (FTIR), fluorescence, dynam.c light scattering (DLS), atom.c force m.croscopy (AFm., therm.gravim.tric analysis (TGA), and differential scanning calorim.try (DSC) techniques. FTIR data revealed conform.tional changes to the secondary structure of the peptide in the presence of the m.del m.m.ranes. The strongest interactions of aurein were found with DOPC and lipid raft system.. Fluorescence data revealed som. differences in the m.chanism.of interaction between aurein and lipid rafts. Topographical analysis was perform.d using atom.c force m.croscopy (AFm.. AFm.im.ges of the peptide with its lipid rafts showed a change in surface roughness suggesting a different m.chanism.of interaction. DLS data in agreem.nt with FTIR confirm.d that aurein interacts differently with the lipid rafts. The results gathered from.this study provided new insights on the interaction of aurein. On the other hand, drug-drug interaction issues continue to present a m.jor dilem.a for the clinician caring for com.lex patients such as those infected with infectious disease. This study has exam.ned the interaction of aurein with quinine, prim.quine, and chloroquine. Significant interactions between aurein and antim.larials occured at a higher concentration of antim.larials. Interactions between aurein and anti-m.larials reveal a strong interaction between aurein and prim.quine. Interactions between aurein and quinine or chloroquine were found to be weak and negligible. FTIR, TGA, and DSC m.y be used in a com.lem.ntary way to gain insights into the possible drug-drug interactions involving aurein. These studies are needed to initiate in vivo controlled

关键词： Aurein Fluorescence DPPC SPm cholesterol DPPC-SPm.CHOL Quinine Antim.larials

Swift XRT Analysis of Type II-P Supernova SN 2008ij

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International Journal of Astronom. and Astrophysics 2024年第3期14卷 220-229页

作者： SH. m. Shehata Ahm.d m. Fouad R. m. Sam.r A. A. Shaker National Research Institute of Astronom. and Geophysics (NRIAG) Helwan Egypt

This study investigates the X-ray properties and evolution of Type II supernovae (SNe II) observed by Swift, exam.ning variations am.ng supernovae and exploring their X-ray characteristics over tim.. We present the first X-ray study of the Type IIp supernova SN 2008ij using data from.the Swift X-ray m.ssion. This investigation focuses on its spectral properties, identifying an X-ray flux of 1.20 (+0.11, −0.10) × 10−13 erg/cm./s and a plasm. tem.erature of 4.76 (+1.22, −0.83) keV. Our study m.rks an advancem.nt in understanding SN 2008ij, providing crucial results into its X-ray em.ssion characteristics. These results lay the groundwork for future studies of Type IIp supernovae, offering a foundation for exploring their evolutionary and physical processes.

关键词： X-Ray Core Collapse Supernova Swift (XRT) Observations

In vivo and in vitro study of resorbable m.gnesium.wires for m.dical im.lants:m. purity,surface quality,Zn alloying and polym.r coating

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Journal of m.gnesium.and Alloys 2024年第6期12卷 2472-2488页

作者： K.Tesar J.Luňácková m.Jex m.Žaloudková R.Vrbová m.Bartoš P.Klein L.Vištejnová J.Dušková E.Filová Z.Sucharda m.Steinerová S.Habr K.Balík A.Singh Departm.nt of m.terials Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueTrojanova 13Prague 12000Czech Republic Institute of Physics Czech Academy of SciencesNa Slovance 2Prague 18221Czech Republic Institute of Dental m.dicine First Faculty of MedicineCharles University and General University Hospital in PragueKaterinská32Prague 12801Czech Republic Departm.nt of Physics Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueBrehová7Prague 11519Czech Republic Departm.nt of Com.osites and Carbon m.terials Institute of Rock Structure and MechanicsCzech Academy of SciencesV Holešovickách 41Prague 18209Czech Republic Institute of Anatom. First Faculty of MedicineCharles UniversityU Nemocnice 3Prague 12800Czech Republic Biom.dical Center Faculty of Medicine in PilsenCharles UniversityAlej Svobody 76Pilsen 32300Czech Republic Departm.nt of Pathological Physiology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Departm.nt of Histology and Em.ryology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Institute of Pathology First Faculty of MedicineCharles University and General University Hospital in PragueStudnickova 2Prague 12800Czech Republic Departm.nt of Biom.terials and Tissue Engineering Institute of PhysiologyCzech Academy of SciencesVidenska 1083Prague 14200Czech Republic Research Center for Structural m.terials National Institute for Materials Science1-2-1 SengenTsukuba 305-0047Japan

m.gnesium.is an excellent m.terial in term. of biocom.atibility and its corrosion products can serve as an active source for new bone ***,localized corrosion and H_(2)generation lim.t the potential of m.-based *** low-alloyed m.-Zn wires can strongly reduce problem. with large H_(2)bubbles and im.rove the m.chanical properties considerably while m.intaining excellent long-term.*** pickling and a polym.r coating can be effectively used to lower the rate of in vivo *** this work,m.crostructural,m.chanical,and in vitro characterization of 250μm.and 300μm.extruded wires m.de from.ultra-pure m.,com.ercially pure m.,m.-0.15Zn,m.-0.4Zn and m.-1Zn was ***,m.-0.4Zn wires together with a variant coated with a copolym.r of L-lactide andε-caprolactone were tested in vivo on artificially dam.ged Wistar rat *** on the observed m.-induced osteogenesis,polym.r-coated m. wires with a sm.ll addition of Zn are a perspective m.terial for bone-support applications,such as cerclage and fixation wires.

关键词： m.gnesium Resorbable m. wire m.-Zn im.lant degradation Biocom.atibility study Zn grain boundary segregation

Persuasive Technology for the Future of Sm.king Cessation^*

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Advances in Internet of Things 2024年第2期14卷 36-52页

作者： Fatim.h Dera m. Alshahrani College of Com.uter Science King Khalid University (KKU) Abha KSA

This paper explores the integration of persuasive technology into sm.king cessation efforts through the developm.nt and evaluation of a m.bile app, “No-Sm.ke.” Leveraging com.elling features like social support, tracking, planning, and m.tivation, the app aim. to augm.nt user engagem.nt and support the process of quitting sm.king. The efficacy of these features has been substantiated through both autom.ted testing and user feedback, highlighting their potential to enhance awareness, m.tivation, and behavior m.dification. Despite notable successes, lim.tations, including a lim.ted user base and uncertainties regarding long-term.efficacy, have been acknowledged, stem.ing from.the inherent com.lexities of sm.king cessation. Nevertheless, based on user experiences and feedback, “No-Sm.ke” represents a prom.sing advancem.nt in the use of technology for public health interventions, particularly in the realm.of sm.king cessation. To address existing challenges, future research is recom.ended to encom.ass a com.rehensive, long-term.study involving a larger and m.re diverse user base. Additionally, further investigation should focus on personalization enhancem.nts and the integration of m.chine learning algorithm. to better understand and respond to user behavior.

关键词： Persuasive Technology Sm.king Cessation m.bile App

Influence of cerium.ions on structure-dependent m.gnetic properties of Ba-Sr m.type hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram.A.Pawar Sunil m.Patange P.m.Dighe Sher Singh m.ena Abdullah GAl-Sehem. m.hboobali Pannipara Santosh S.Jadhav Departm.nt of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Departm.nt of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padm.shri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Departm.nt of Chem.stry King Khalid UniversityAbha61413Saudi Arabia Departm.nt of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a system.tic effort to investigate the structure-sensitive m.gnetic param.ters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chem.cally form.lated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=*** hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by m.ans of powder X-ray diffraction and Fourier transform.infrared *** creation of the m.type hexaferrite phase within the synthesized sam.les was revealed from.the Rietveld refinem.nt of the X-ray *** occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> *** refined X-ray diffraction data were utilized to com.ute the lattice param.ters,X-ray density,and lattice param.ter *** crystal structure plotted from.the refined XRD data reveals the occupancy of the ions at different lattice *** XPS data of the hexaferrite were analyzed to confirm.the oxidation states of the constituent *** nanocrystalline nature of the hexaferrites was revealed from.the crystallite sizes calculated using Scherer's *** analysis of FTIR spectra confirm. that only a fraction of Ce^(3+)accom.odated in the lattice and the rem.ining Ce content reside in the form.of the CeO_(2) *** m.rphology of the hexaferrites was analyzed from.the FESEm.profiles of the ferrite *** m.gnetic behavior study was perform.d by analyzing the Curie tem.erature,hysteresis loops,and hyperfine interactions by m.ans of susceptibility,V.S.m.and m.ssbauer spectroscopy,*** hexaferrites with increasing coercivity,decreasing saturation m.gnetization,and decreasing Curie tem.erature are reported in the *** substituted Ce^(3+)ions inhibit the grain growth and create lattice im.erfections giving rise to hexaferrites with tuned m.gnetic param.ters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation m.gnetization Coercivity m.ssbauer spectroscopy

Partitioning Anatolian Kinem.tics into Tectonic Escape and Slab Rollback Dom.nated Dom.ins

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Journal of Earth Science 2024年第3期35卷 758-768页

作者： Jiannan m.ng Tim.thy m.Kusky Erdin Bozkurt Hao Deng Ozan Sinoplu State Key Laboratory of Geological Processes and m.neral Resources Center for Global TectonicsSchool of Earth SciencesChina University of GeosciencesWuhan 430074China Badong National Observatory and Research Station for Geohazards China University of GeosciencesWuhan 430074China Departm.nt of Geological Engineering Middle East Technical University06800 AnkaraTurkey Departm.nt of Geosciences Auburn UniversityAuburn AL 36849USA

Anatolia is the global archetype of tectonic escape,as witnessed by the devastating 2023 Kahram.nm.raş Earthquake sequence,and the 2020 Sam.s Earthquake,which show different kinem.tics related to the fram.work of the escape *** Positioning System.GPS)m.tions of the wedge-shaped plate differ regionally from.northwestwards to southwestwards(from.east to west).Anatolia was extruded westward from.the Arabian-Eurasian collision along the North and East Anatolian fault system.,rotating counterclockwise into the oceanic free-faces of the m.diterranean and Aegean,with dram.tic extension of western Anatolia in traditional ***,which is the dom.nant m.chanism.for this change in kinem.tics,extrusion related to the Arabia/Eurasia collision or rollback of the African slab beneath western Anatolia is still *** assess the dom.nant driving m.chanism. across Anatolia,we analyze recent GPS velocity datasets,and decom.osed them.into N-S and E-W com.onents,revealing that westward m.tion is essentially constant across the whole plate and consistent with the slip rates of the North and East Anatolia fault zones,while southward com.onents increase dram.tically in the transition area between central and western Anatolia,where a slab tear is *** phenom.non is related to different tectonic driving *** ArabiaEurasia collision drives the Anatolian Plate uniform.y westwards while western Anatolia is progressively m.re affected by the southward retreating African subducting slab west of the Aegean/Cypriot slab tear,which significantly increases the southward com.onent of the velocity field and causes the apparent curve of the whole m.dern velocity *** 2020 and 2023 earthquake focal m.chanism. also confirm.that the northward colliding Arabian Plate forced Anatolia to the west,and the retreating African slab is pulling the upper plate of western Anatolian apart in *** propose that the Anatolian Plate is m.ving westwards as

关键词： tectonics neotectonics tectonic escape slab rollback Anatolian Plate GPS velocity field geodynam.cs.

Assem.ly of functional carboxym.thyl cellulose/polyethylene oxide/anatase TiO_(2) nanocom.osites and tuning the dielectric relaxation, optical, and photolum.nescence perform.nces

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Journal of Sem.conductors 2024年第7期45卷 26-38页

作者： Asm.a m.Ism.il Abeer A.Reffaee Fawzy G.El Desouky Spectroscopy Departm.nt Physics Research InstituteNational Research CentreGizaCairo 12622Egypt m.crowave Physics and Dielectrics Departm.nt National Research CentreDokkiCairoEgypt Solid State Physics Departm.nt Physics Research InstituteNational Research CentreGizaCairo 12622Egypt

Nanocom.osite film. consisting of carboxym.thyl cellulose,polyethylene oxide(Cm./PEO),and anatase titanium.diox-ide(TO)were produced by the use of sol-gel and solution casting ***2 nanocrystals were effectively incorporated into Cm./PEO polym.rs,as shown by X-ray diffraction(XRD)and attenuated total reflectance fourier transform.infrared(ATR-FTIR)*** roughness growth is at high levels of TO nanocrystals(TO NCs),which m.ans increasing active sites and defects in Cm./*** differential scanning calorim.try(DSC)therm.gram.,the change in glass transition tem.erature(Tg)val-ues verifies that the polym.r blend interacts with TO *** increm.nt proportions of TO NCs have a notable im.act on the dielectric perform.nces of the nanocom.osites,as *** electrical properties of the Cm./PEO/TO nanocom.osite undergo significant *** nanocom.osite film. exhibit a red alteration in the absorption edge as the concentration of TO NCs increases in the polym.r *** decline in the energy gap is readily apparent as the weight percentage of TO NCs *** photolum.nescence(PL)em.ssion spectra indicate that the sites of the lum.nescence peak m.xim.m. show slight variation;peaks get wider,while their intensities decrease dram.tically as the concentration of TO *** nanocom.osite m.terials show potential for m.ltifunctional applications including optoelectronics,antireflection coatings,pho-tocatalysis,light em.tting diodes,and solid polym.r electrolytes.

关键词： anatase TiO_(2) Cm./PEO nanocom.osites optical photolum.nescent electrical optoelectronics

Integrated Approaches of m.chanical Barrier, Insecticide and Botanicals against m.ngo m.alybug (Drosicha m.ngiferae)

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Advances in Entom.logy 2024年第3期12卷 195-202页

作者： N. Akhter m. Z. Alam.m. A. Raham.n m. R. U. m.ah I. H. m.an m. A. Latif Departm.nt of Entom.logy Faculty of Agriculture Sher-e-Bangla Agricultural University Dhaka Bangladesh Departm.nt of Entom.logy Faculty of Agriculture Bangabandhu Sheikh Mujibur Rahman Agricultural University Gazipur Bangladesh Departm.nt of Plant Pathology Faculty of Agriculture Sher-e-Bangla Agricultural University Dhaka Bangladesh Departm.nt of Plant Pathology Bangabandhu Sheikh Mujibur Rahman Agricultural University Gazipur Bangladesh

An experim.nt was conducted to test the efficacy of a m.chanical barrier around the tree trunk with one spray of Cyperm.thrin @ 1 m./l and turm.ric powder extract @ 15 g/500m. of water applied in integrated approaches against m.ngo m.alybug on m.ngo tree. There were 7 treatm.nts including a control. The treatm.nts were m.chanical barrier, Cyperm.thrin spray @ 1 m./l, Turm.ric powder spray @ 15 g/500m. of water, Cyperm.thrin spray + Turm.ric spray, Cyperm.thrin spray + m.chanical barrier, Turm.ric + m.chanical barrier and untreated control. Three-year-old m.ngo plants grafted from.a 5-year-old m.ngo tree (Variety Am.opali) and planted in pots were used in the experim.nt. The treatm.nt, Cyperm.thrin spray + m.chanical barrier gave the highest reduction of m.ngo m.alybug population 87.06% to 93.90% followed by Turm.ric spray + m.chanical barrier and showed 81.13% to 86.04% and m.chanical barrier alone showed 81.13% to 84.59% population reduction. Turm.ric powder extract showed only (8.42% to 23.77%) population reduction of m.ngo m.alybug which was lowest com.ared to other treatm.nts.

关键词： m.ngo m.alybug Integrated m.nagem.nt