(n,p), (n,2n), (n,d), and (n,α) cross-section calculations of

Oxygen is one of the elements which interacts with emitted neutrons after fission reactions. Oxygen exists abundantly both in nuclear fuel (UO2) and moderators (H2O). Nuclear reactions of oxygen with neutrons are important in terms of stability of nuclear fuel and neutron economy. In this study, equilibrium and pre-equilibrium models have been used to calculate (n,p), (n,d), (n,2n) and (n,α) nuclear reaction cross-sections of 16O. In these calculations, neutron incident energy has been taken up to 40 MeV. Hybrid and Standard Weisskopf-Ewing Models in ALICE-2011 program, Weisskopf-Ewing and Full Exciton Models in PCROSS program, and Cascade Exciton Model in CEM03.01 program have been utilized. The calculated results have been compared with experimental and theroretical cross-section data which are obtained from libraries of EXFOR and ENDF/B VII.1

Calculation of photo-nuclear reaction cross sections for

Because of the high thermal expansion coefficient of uranium, the fuel used in nuclear power plants is usually in the form of UO2 which has ceramic structure and small thermal expansion coefficient. UO2 include one uranium atom and two oxygen atoms. After fission progress, total energy values of emitted gamma are about 14 MeV. This gamma energy may cause transmutation of 16O isotopes. Transmutation of 16O isotopes changes physical properties of nuclear fuel. Due to above explanations, it is very important to calculate photo-nuclear reaction cross sections of 16O. In this study; for (γ,p), (γ,np), (γ,n) and (γ,2n) reactions of 16O, photo-nuclear reaction cross-sections were calculated using different models for pre-equilibrium and equilibrium effects. Taking incident gamma energy values up to 40 MeV, Hybrid and Cascade Exciton Models were used for pre-equilibrium calculations and Weisskopf-Ewing (Equilibrium) Model was used for equilibrium model calculations. Calculation results were compared with experimental and theoretical data. While experimental results were obtained from EXFOR, TENDL-2013, JENDL/PD-2004 and ENDF/B VII.1 data base were used to get theoretical results

The investigation of the neutron emission spectra of Th-232 and U-238 for neutron incident energy from 2 to 18 MeV

WOS: 000236428200002In this study, experimental neutron-emission spectra produced by (n, xn) reactions on nuclei Th-232 have been compared with experimental U-238(n, xn) neutron-emission spectra from 2 to 18 MeV. Angle-integrated cross-sections in neutron induced reactions on targets U-238 have been calculated at the bombarding energies from 2 to 18 MeV. In the calculations, the geometry dependent hybrid model and the cascade exciton model including the effects of pre-equilibrium have been used. In addition, we have described how multiple pre-equilibrium emissions can be included in the Feshbach-Kerman-Koonin (FKK) fully quantum-mechanical theory. By analyzing (n, xn) reaction on U-238 with the incident energy from 2 to 18 MeV, the importance of multiple pre-equilibrium emission can be seen clearly. All A calculated results have been compared with experimental data. The obtained results have been discussed and compared with the available experimental data and found agreement with each other. (c) 2005 Elsevier Ltd. All rights reserved

The investigation of the neutron emission spectra of 232Th and 238U for neutron incident energy from 2 to 18 MeV

In this study, experimental neutron-emission spectra produced by (n, xn) reactions on nuclei 232Th have been compared with experimental 238U(n, xn) neutron-emission spectra from 2 to 18 MeV. Angle-integrated cross-sections in neutron induced reactions on targets 238U have been calculated at the bombarding energies from 2 to 18 MeV. In the calculations, the geometry dependent hybrid model and the cascade exciton model including the effects of pre-equilibrium have been used. In addition, we have described how multiple pre-equilibrium emissions can be included in the Feshbach-Kerman-Koonin (FKK) fully quantum-mechanical theory. By analyzing (n, xn) reaction on 238U with the incident energy from 2 to 18 MeV, the importance of multiple pre-equilibrium emission can be seen clearly. All calculated results have been compared with experimental data. The obtained results have been discussed and compared with the available experimental data and found agreement with each other. © 2005 Elsevier Ltd. All rights reserved

Calculations of proton-induced neutron production cross sections on Th-232 up to 1.6 GeV

WOS: 000238275300007The Th-232(p, xn) and Th-232(p, np) cross sections for incident proton energies in the range of 10 to 1600 MeV have been calculated by using a cascade-exiton model (CEM) combining essential features of the exciton model and intranuclear cascade models. The level density parameter effects are investigated. The calculation results are compared with the available measured data

Enhanced antibacterial and antiparasitic activity of multifunctional polymeric nanoparticles

Due to the resistance to drugs, studies involving the combination and controlled release of different agents are gradually increasing. In this study, two different active ingredients, known to have antibacterial and antiparasitic activities, were encapsulated into single polymeric nanoparticles. After co-encapsulation their antibacterial and antileishmanial activity was enhanced approximately 5 and 250 times, respectively. Antibacterial and antileishmanial activities of caffeic acid phenethyl ester and juglone loaded, multifunctional nanoformulations (CJ4-CJ6-CJ8) were also evaluated for the first time in the literature comparatively with their combined free formulations. The antibacterial activity of the multifunctional nanoformulation (CJ8) were found to have a much higher activity (MIC values 6.25 and 12.5 μg ml-1 for S. aureus and E. coli, respectively) than all other formulations. Similar efficacy for CJ8 was obtained in the antiparasitic study against the Leishmania promastigotes and the IC50 was reduced to 0.1263 μg ml-1. The high activity of multifunctional nanoparticles is not only due to the synergistic effect of the active molecules but also by the encapsulation into polymeric nanoparticles. Therefore, it has been shown in the literature for the first time that the biological activity of molecules whose activity is increased by the synergistic effect can be improved with nanosystems

Quercetin-loaded nanoparticles enhance cytotoxicity and antioxidant activity on C6 glioma cells

Erdemir, Aysegul/0000-0002-6099-4903; Mansuroglu, Banu/0000-0001-8440-9118;WOS: 000524166500001PubMed: 32192406Quercetin (Qu) is a natural flavonoid present in many commonly consumed food items. the dietary phytochemical quercetin prevents tumor proliferation and is a potent therapeutic cancer agent. the purpose of this study was to synthesize and characterize quercetin-loaded poly(lactic-co-glycolic acid) nanoparticles (Qu(1)NP, Qu(2)NP, and Qu(3)NP) with different size and encapsulation properties and to evaluate their in vitro activity on C6 glioma cells. Nanoparticles were synthesized by single emulsion solvent evaporation method. Then, particle size, zeta potential, polydispersity index and encapsulation efficiency of nanoparticles were determined. Particle size of Qu(1)NP, Qu(2)NP, and Qu(3)NPs were determined as 215.2 +/- 6.2, 282.3 +/- 7.9, and 584.5 +/- 15.2 nm respectively. Treating C6 glioma cells with all nanoparticle formulations effectively inhibited the cell proliferation. Qu(1)NPs were showed the lowest IC50 value in 48 h with 29.9 mu g/ml and achieved higher cellular uptake among other nanoparticles and Qu. Additionally, 48-h treatment with Qu(1)NPs significantly decreased MDA level (14.90 nmol/mu g protein) on C6 glioma cells which is related to reduced oxidative stress in cells. Findings of this study revealed that quercetin's cellular uptake and anti-oxidant activity is improved by small-sized Qu(1)NPs in C6 glioma cells.Research Foundation of Yildiz Technical UniversityYildiz Technical University [FKG-2017-3067]This work was supported by the Research Foundation of Yildiz Technical University under Grant [FKG-2017-3067]

Investigation of anti-cancer activity of hesperetin and hesperetin loaded polymeric nanoparticles on C6 glioma cells

WOS: 000437674105215

Chemical composition of the essential oils of Centaurea tomentella Hand.-Mazz. and C. haussknechtii Boiss. (Asteraceae) collected wild in Turkey and their activity on microorganisms affecting historical art craft

In the present study the chemical composition of the essential oils from aerial parts of Centaurea tomentella Hand.-Mazz. and C. haussknechtii Boiss. collected in Turkey was evaluated by GC and GC-MS. The main components of C. tomentella L. were hexadecanoic acid (19.7%), caryophyllene oxide (6.6%) and spathulenol (4.8%) whereas C. haussknechtii was rich in hexadecanoic acid (26.2%), (Z,Z)-9,12-octadecadienoic acid (19.3%), heptacosane (5.3%) and nonacosane (5.1%). Antibacterial and antifungal activities against some microorganisms infesting historical art craft, were also determined