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Chiral phase structure of the sixteen meson states in the SU(3) Polyakov linear-sigma model for finite temperature and chemical potential in a strong magnetic field

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Chinese Physics C 2019年第3期43卷 56-71页

作者： Abdel Nasser Tawfik Abdel magied Diab m.T.hussein Nile University Juhayna sq.of 26th-July-Corridor16453 GizaEgypt Frankfurt Institute for Advanced Studies Ruth Moufang Str.160438 FrankfurtGermany and World Laboratory for Cosmology And Particle Physics(WLCAPP)11571 CairoEgypt Egyptian Center for Theoretical Physics(ECTP) MTI University11571 CairoEgypt and World Laboratory for Cosmology And Particle Physics(WLCAPP)11571 CairoEgypt Physics Department Faculty of ScienceCairo University12613 GizaEgypt

In characterizing the chiral phase-structure of pseudoscalar(J^(pc) = 0^(-+)), scalar(J^(pc) = 0^(++)), vector(J^(pc) =1^(--)) and axial-vector(J^(pc) = 1^(++)t) meson states and their dependence on temperature, chemical potential, and magnetic field,we utilize the SU(3) Polyakov linear-sigma model(PLSm) in the mean-field approximation. We first determine the chiral(non)strange quark condensates,σ_l and σ_s, and the corresponding deconfinement order parameters, φ and φ~*, in thermal and dense(finite chemical potential) medium and finite magnetic field. The temperature and the chemical potential characteristics of nonet meson states normalized to the lowest bosonic matsubara frequency are analyzed. We note that all normalized meson masses become temperature independent at different critical temperatures. We observe that the chiral and deconfinement phase transitions are shifted to lower quasicritical temperatures with increasing chemical potential and magnetic field. Thus, we conclude that the magnetic field seems to have almost the same effect as the chemical potential, especially on accelerating the phase transition, i.e. inverse magnetic catalysis. We also find that increasing the chemical potential enhances the mass degeneracy of the various meson masses, while increasing the magnetic field seems to reduce the critical chemical potential, at which the chiral phase transition takes place. Our mass spectrum calculations agree well with the recent PDG compilations and PNJL, lattice QCD calculations, and QmD/UrQmD simulations.

关键词： Chiral transition magnetic fields magnetic catalysis critical temperature viscous properties of QGP

Search for dark matter production in association with the Z′ boson at the LHC in pp collisions at √s=8 TeV using monte Carlo simulations

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Chinese Physics C 2021年第8期45卷 1-11页

作者： S.Elgammal m.A.Louka A.Y.Ellithi m.T.hussein Centre for theoretical physics The British University in EgyptCairoEgypt Physics Department Faculty of ScienceCairo UniversityEgypt

This analysis evaluates the possibility of the search for Dark matter(Dm)particles using events with a Zf heavy gauge boson and a large missing transverse momentum at the Large Hadron Collider(LHC).We consider the muonic decay of Z'.The analyzed monte Carlo samples were the Open simulated files produced by the Compact muon Solenoid(CmS)collaboration for proton-proton collisions,corresponding to an integrated luminosity of the LHC run-I with 19.7 fb^(-1) at √s=8 *** scenarios,namely a simplified benchmark scenario,called Dark Higgs,and the effective field theory(EFT)formalism,were used for *** were set on Z′,dark matter masses,and the cutoff scale of the EFT.

关键词： dark matter new heavy gauge boson Large Hadron Collider Compact muon Solenoid

Synthesis and Spectral Properties of 4-（2,5-Dimethoxyphenyl- methelene）-2-phenyl-5-oxazolone （DmPO）

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Chinese Journal of Chemistry 2012年第3期30卷 563-569页

作者： EI-Daly, Samy A Asiri, Abdullah m Alamry, Khalid A hussein, mahmoud A Chemistry Department Faculty of Science King Abdulaziz University P.O. Box 80203 Jeddah 21589 Saudi Arabia The Center of Excellence for Advanced materials King Abdulaziz University Jeddah 21589 P.O. Box 80203 Saudi Arabia Department of Chemistry Faculty of Science Tanta University 31527 Tanta Egypt Chemistry Department Faculty of Science Assiut University Assiut 71516 Egypt

An interesting flourophore, 4-（2,5-dimethoxyphenylmethelene）-2-phenyl-5-oxazolone （DmPO） was synthesized by mixing an equivalent molar quantity of hippuric acid and 2,5-dimethoxybenzaldehyde in acetic anhydride in the presence of anhydrous sodium acetate. The absorption and fluorescence characteristics of 4-（2,5-dimethoxy-phenyl- methelene）-2-phenyl-5-oxazolone （DmPO） were investigated in different solvents. DmPO dye exhibits red shift in both absorption and emission spectra as solvent polarity increases, indicating change in the dipole moment of mole- cules upon excitation due to an intramolecular charge transfer interaction. The fluorescence quantum yield depends strongly on the properties of the solvents, which was attributed to positive and negative solvatokinetic effects. A crystalline solid of DmPO gave strong excimer like emission at 630 nm due to the excitation of molecular aggregates. This is expected from the idealized crystal structure of the dye that belongs to the B-type class of Steven＇s Classifica- tion. DmPO displayed fluorescence quenching by triethylamine via nonemissive exciplex formation.

关键词： 4-(2,5-dimethoxy-phenylmethelene)-2-phenyl-5-oxazolone (DmPO) effect of medium fluorescencequantum yield solid state emission

Predicting grain size-dependent superplastic properties in friction stir processed ZK30 magnesium alloy with machine learning methods

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Journal of magnesium and Alloys 2024年第5期12卷 1931-1943页

作者： farid Bahari-Sambran Fernando Carreno C.m.Cepeda-Jiménez Alberto Orozco-Caballero Physical metallurgy Department CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain Department of mechanical Engineering Chemistry and Industrial DesignPolytechnic University of MadridRonda de Valencia 328012MadridSpain

The aim of this work is to predict,for the first time,the high temperature flow stress dependency with the grain size and the underlaid deformation mechanism using two machine learning models,random forest(RF)and artificial neural network(ANN).With that purpose,a ZK30 magnesium alloy was friction stir processed(FSP)using three different severe conditions to obtain fine grain microstructures(with average grain sizes between 2 and 3μm)prone to extensive superplastic *** three friction stir processed samples clearly deformed by grain boundary sliding(GBS)deformation mechanism at high *** maximum elongations to failure,well over 400% at high strain rate of 10^(-2)s^(-1),were reached at 400℃ in the material with coarsest grain size of 2.8μm,and at 300℃ for the finest grain size of 2μ***,the superplastic response decreased at 350℃ and 400℃ due to thermal instabilities and grain coarsening,which makes it difficult to assess the operative deformation mechanism at such *** work highlights that the machine learning models considered,especially the ANN model with higher accuracy in predicting flow stress values,allow determining adequately the superplastic creep behavior including other possible grain size scenarios.

关键词： machine learning Artificial intelligence magnesium alloys Superplasticity Friction stir processing Grain coarsening

Assaying the allelopathic effects of Eucalyptus camaldulensis in a nursery bed incorporated with leaf litter

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Journal of Forestry Research 2018年第3期29卷 592-598页

作者： Romel Ahmed mohammad Shafioul Alam.farid Uddin Ahmed m.K.Hossain Department of Forestry and Environmental Science Shahjalal University of Science and TechnologySylhet 3114Bangladesh ministry of Public Administration TeknafCoxsbazarDhaka 4761Bangladesh Arannayk Foundation House 21 Western RoadDOHSBananiDhaka 1206Bangladesh Institute of Forestry and Environmental Science University of ChittagongChittagong 4331Bangladesh

Allelopathic effects of Eucalyptus camaldulensis Dehnh. were confirmed in Petri dish and pot experiments in our previous studies. However, the degree to which such effects under controlled experiments exist in more complex ecological settings remains to be tested. Thus, the present study was carried out by incorporating different proportions of ground litter of E. camaldulensis in soil. The growth of three agricultural crops: falen(Vigna unguiculata(L.) Walp.), chickpea(Cicer arietinum L.), and arhor(Cajanus cajan(L.) millsp.), and two tree species, kala koroi(Albizia procera(Roxb.) Benth.) and ipil ipil(Leucaena leucocephala(Lam.) de Wit) were tested. There were inhibitory effects of leaf litter on germination, shoot and root growth, leaf number, and collar diameter as well as a reduction of nodulation by legume crops(25–80%reduction). The extent of the effects was dependent on the proportion of leaf litter, the species and the type of traits. In contrast to shoot growth, the effect on root growth was more severe. No effect on germination was found with the agriculture crops while the two tree species showed reduced germination. The effect was greater in the presence of higher proportions of leaf litter mixed in soil while in some cases lower proportions stimulated growth. Not all species were suppressed; A. procera, C. cajan, V. unguiculata showed compatible growth while C. arietinum and *** were found incompatible. This study provides evidence that E. camaldulensis has allelopathic potential under field conditions and a careful selection of associated crops in agroforestry systems is highly recommended.

关键词： Allelopathy Eucalyptus camaldulensis Inhibitory effects Germination Growth Nodulation

An Investigation of ~4He+^(12)C and ~4He+^(16)O Reactions Using the Cluster model

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Communications in Theoretical Physics 2012年第7期58卷 135-140页

作者： A.H.Al-Ghamdi Awad A.Ibraheem m.El-Azab farid Physics Department Faculty of ScienceKing Abdul Aziz UniversityJeddahSaudi Arabia Physics Department Al-Azhar UniversityAssiut BranchAssiut 71524Egypt Physics Department King Khalid UniversityAbhaSaudia Arabia Physics Department Assiut UniversityAssiut 71516Egypt

The α-target semimicroscopic single folding potentials have been derived by folding a composite (repul-sive and attractive) effective α-α interaction with the α-cluster distribution density in the target nuclei. The obtained potentials are considered as the real part of the nuclear optical model potentials, while the imaginary parts are phe-nomenologicaly expressed using the Woods-Saxon form. Nine sets of measured experimental data of the 4He+12C and 4 He+16O elastic rainbow scattering over the energy range 80-240 meV are analyzed using the obtained potentials. The data are successfully reproduced using the extracted potentials. The resulted reaction cross sections are also investigated and compared with the available corresponding data.

关键词： optical model elastic scattering folding potential cluster model

Electroexcitation of Low-Lying Particle-Hole RPA States of ^(16)O with WBP Interaction

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Communications in Theoretical Physics 2014年第12期61卷 839-846页

作者： Ali H.Taqi R.A.Radhi Adil m.hussein Department of Physics College of Science Kirkuk University Department of Physics College of Science University of Baghdad Department of Physics College of Science University of Sulaimani

The nuclear structure of 16 O is studied in the framework of the particle–hole random phase approximation(ph RPA). The Hamiltonian is diagonalized within a model space with particle orbits {1d5/2,1d3/2, and 2s1/2} and the hole orbits {1p3/2and 1p1/2} using Warburton and Brown interaction WBP. The ph RPA calculations are tested, by comparing the electron scattering form factors with the available experimental data. The results of electron scattering form factors and reduced transition strength for the states: 1-, T = 0(7.116 me V); 2-, T = 1(12.968 me V); 2-, T = 1(20.412 me V); and 3-, T = 0(6.129 me V) are interpreted in terms of the harmonic-oscillator(HO) wave functions of size parameter b. The occupation probabilities of the single particle and hole orbits are calculated. The spurious states are removed by adding the center of mass(Cm) correction to the nuclear Hamiltonian. A comparison with the available experiments data is presented.

关键词： random-phase approximation collective excitations and electromagnetic form factors

Helicobacter pylori and gastric cancer in the middle East: A new enigma?

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World Journal of Gastroenterology 2010年第26期16卷 3226-3234页

作者： Nawfal R hussein Institute of Infection Immunity and Inflammation and the Centre for Biomolecular Sciences University of Nottingham Nottingham NG7 2RD United Kingdom

The middle East is the home of ethnic groups from three main backgrounds: Semitic (Arabs and Jews), Indo-European (Persians and Kurdish) and Turkic (Turkish and Turkmens). Its geographic location, which has been under continuous influences from Asia, Europe and Africa, has made it an ideal site for epidemiological studies on Helicobacter pylori (H. pylori) infection and genotyping. The gastric cancer rate differs in this region from very high in Iran (26.1/105) to low in Israel (12.5/105) and very low in Egypt (3.4/105). Epidemiological studies showed that the prevalence of H. pylori is almost similar in those countries with a high level of infection in childhood. Importantly, the frequency of vacA s1 and m1 regions and cagA+ genotypes were higher in non Semitic populations who inhabit the North than Semitic populations, the inhabitants of Southern parts of the middle East. H. pylori infection prevalence, distribution pattern of virulence factors, diet and smoking could not have explained the difference in cancer rate. This reflects the multifactorial aetiology of gastric cancer and suggests that H. pylori infection does not always directly correlate with the risk for gastrointestinal disease, such as gastric cancer. Further detailed investigations and international comparative studies of each risk factor needto be performed to investigate whether this represents a true enigma.

关键词： Helicobacter pylori middle East Gastric cancer dupA cagA vacA iceA

mechanical and thermodynamical stability of BiVO4 polymorphs using first-principles study

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Chinese Physics B 2017年第3期26卷 395-403页

作者： A K m.farid UI Islam md Nurul Huda Liton H m Tariqul Islam md Al Helal md Kamruzzaman Department of Computer Science and Engineering Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Physics Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Chemistry Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Physics and materials Science and Center of Super-Diamond and Advanced Films (COSDAF) City University of Hong Kong Hong Kong SAR China

First principles calculations of structural, electronic, mechanical, and thermodynamic properties of different poly- morphs of BiVO4 are performed using Bender-type plane/wave ultrasoft pseudopotentials within the generalized gradient approximation （GGA） in the flame of density functional theory （DFT）. The calculated structural and electronic properties are consistent with the previous theoretical and experimental results. The electronic structures reveal that m-BiVO4, op- BiVO4, and st-BiVO4 have indirect band gaps, on the other hand, zt-BiVO4 has a direct band gap. From the DOS and mulliken＇s charge analysis, it is observed that only m-BiVO4 has 6s2 Bi lone pair. Bond population analysis indicates that st-BiVO4 shows a more ionic nature and a similar result is obtained from the elastic properties. From the elastic prop- erties, it is observed that st-BiVO4 is more mechanically stable than the others, st-BiVO4 is more ductile and useful for high electro-optical and electro-mechanical coupling devices. Our calculated thermodynamic properties confirm the similar characteristics found from electronic and elastic properties, m-BiVO4 is useful as photocatalysts, solid state electrolyte, and electrode and other polymorphs are applicable in electronic device fabrications.

关键词： BiVO4 crystal structure lone pair mechanical stability