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621.
622.
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. 相似文献
623.
Noof Ali Alenazi Khalid Ahmad Alamry Mahmoud Ali Hussein Mahmoud Abdelkhalek Elfaky Abdullah Mohamed Asiri 《先进技术聚合物》2019,30(6):1493-1505
Polyethersulfone (PES) has been widely used in membrane technology and used to purify water in water treatments application or as a dialyzer to purify blood in hemodialysis. In this work, PES was chemically modified by separately grafting two biomolecules, 4‐aminobenzenesulfonamide (ABS), and 4‐amino‐N‐(5‐methylisoxazol‐3‐yl)benzenesulfonamide (AMBS), on PES backbone, and these modified membranes were blended to unmodified PES, in 1:1 ratio, in order to obtain PES‐b‐PES‐ABS and PES‐b‐PES‐AMBS membranes. The first aim of this study is to measure the anticoagulant properties of the modified membrane by measuring the activated partial thromboplastin time (APTT) and prothrombin time (PT). The second aim of the study is to evaluate the antifouling properties of the modified PES membranes by examining its antimicrobial activity against two Gram‐negative bacteria, which are Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E. coli); two Gram‐positive bacteria, which are Bacillus subtilis (B. subtilis) and Staphylococcus aureus (S. aureus); and a fungus, which is Candida albicans (C. albicans). The results showed that grafting of ABS and AMBS improved overall the hydrophilicity properties of the modified PES membranes. PES‐b‐PES‐ABS membranes showed better anticoagulant properties with 13 seconds for PT and 38 seconds for APPT, in comparison with the control sample (pure plasma), which showed 12 seconds for PT and 30 seconds for APPT. For antimicrobial tests, both PES‐b‐PES‐ABS and PES‐b‐PES‐AMBS membranes did not show any antibacterial activity, but when zinc oxide (ZnO) nanoparticles were added to the modified PES membranes in concentrations between 3% to 5% w/w, PES‐b‐PES‐ABS‐ZnO (M‐4 and M‐5), and PES‐b‐PES‐AMBS‐ZnO (M‐8 and M‐9) nanocomposite membranes showed antibacterial activity against P. aeruginosa and S. aureus. 相似文献
624.
Hajiyan Mohammadhossein Ebadi Soroush Mahmud Shohel Biglarbegian Mohammad Abdullah Hussein 《Journal of Thermal Analysis and Calorimetry》2019,135(2):1451-1464
Journal of Thermal Analysis and Calorimetry - Thermophysical properties, such as thermal conductivity and viscosity, of magnetic nanofluids (MNFs) can be enhanced by applying external magnetic... 相似文献
625.
M. S. Hussein C. Y. Lin A. F. R. Toledo de Piza 《Zeitschrift für Physik A Hadrons and Nuclei》1974,267(2):165-168
We derive a consistency relation connected with the isospin dependence of the effective particle-hole interaction. This relation is applied to the nucleus208Pb and permits to determine one parameter of the effective interaction. 相似文献
626.
In a k-dimensional system of weakly interacting Bose atoms trapped by a spherically symmetric and harmonic external potential, an exact expression is obtained for the rotating ground states at a fixed angular momentum. The result is valid for arbitrary interactions obeying minimal physical requirements. Depending on the sign of a modified scattering length, it reduces to either a collective rotation or a condensed vortex state, with no alternative. The ground state can undergo a kind of quantum phase transition when the shape of the interaction potential is smoothly varied. 相似文献
627.
Dr. H. A. M. Hussein 《Zeitschrift für Physik A Hadrons and Nuclei》1970,230(4):358-370
The decays of the 206 day-Rh102g , 2.9 year-Rh102m and 4.35 min-Tc102 m have been investigated using several sizes of Ge(Li)-counters. From the analysis of gamma spectra from several Rh102-sources, measured over a period of 2.2 years, the gamma rays associated with each activity were identified. Energies and relative gamma intensities of 71 transitions have been determined. 22 transitions are assigned to the decay of 206 day-Rh102g , 16 to 2.9 year-Rh102 and 33, twenty five unreported, to 4.35 min-Tc102m . All except one transition are placed in a level scheme of Ru102. 相似文献
628.
629.
The formation of nonequilibrium thermodynamic system is assumed during the collision of relativistic heavy ions with target nuclei. A simple classical solution of the Boltzmann equation is found and compared with the spectra of particles produced in the Ne-U238 reaction at lab. energies of 250 and 400 MeV per nucleon. The model contains only one fitting parameter tc which is the time required by the system to reach the equilibrium state. 相似文献
630.
Fast-track construction projects have become more popular in recent years in response to growing industry demand. By allowing downstream construction activities to start with incomplete information from upstream design activities, fast-tracking (through overlapping) allows for shorter project duration at the expense of potential rework. This leaves practitioners with the challenge of determining the optimal fast-tracking strategy to meet project schedule requirements while avoiding excessive amounts of rework. This paper presents an optimization-based model that serves as a decision support tool in scheduling fast-track construction activities. The model takes into consideration information exchange between upstream and downstream activities and uses the concepts of sensitivity and evolution to maximize the net benefits of fast-tracking. The model is illustrated on an ongoing construction project, which was analysed under various overlapping scenarios. The results indicate substantial time savings depending on the speed of evolution and sensitivity. The project schedule can be shortened by up to 50 days without causing excessive amounts of rework. 相似文献