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111.
Murat Belivermis Önder Kılıç Yavuz Çotuk Sayhan Topçuoğlu Mahmut Coşkun Akın Çayır 《辐射效应与固体损伤》2013,168(11):903-913
The activity concentrations of gamma emitting radionuclides were measured in surface soil samples from the Thrace region. 232Th, 238U, 226Ra, 40K and 137Cs activities and physico-chemical parameters of the soil samples were determined in samples collected from 73 sampling stations. Radionuclide concentrations measured were compared with those found in the samples from other locations of Turkey and from different countries. The average activity concentrations of 232Th, 238U, 226Ra, 40K and 137Cs were found to be 24.71 ± 8.79, 22.30 ± 7.93, 32.09±12.44, 509.00±160.05, 32.74±29.24 Bq kg?1, respectively. The mean value of the annual effective dose equivalent from the outdoor terrestrial gamma radiation was calculated as 57.2 μ Sv. 相似文献
112.
Exposure of powder forms of DL-2-aminoadipic acid and ammonium acetate to gamma radiation results in the formation of free radicals detected by the electron paramagnetic resonance spectroscopy at room temperature. In these compounds, the observed paramagnetic species were attributed to the HOOCCH2CH2CH2CHCOOH and CH2COONH4 radicals, respectively. The g values and the hyperfine coupling constants of the unpaired electron with the environmental protons were determined for these two radicals. In work, the observed paramagnetic species were found to be stable at room temperature for more than two months. Also, these compounds were characterised by FT-IR and UV–VIS. Their thermal stabilities were determined by TGA and DTA measurements. Thermal analyses were shown to be unstable of the HOOCCH2CH2CH2CH(NH2)COOH and CH3COONH4 against thermo-oxidative decomposition. 相似文献
113.
In this article, we discuss the analytic solution of the fully developed shock waves. The homotopy perturbation method is used to solve the shock wave equation, which describes the flow of gases. Unlike the various numerical techniques, which are usually valid for short period of time, the solution of the presented equation is analytic for 0 < t < ∞. The results presented converge very rapidly, indicating that the method is reliable and accurate. 相似文献
114.
115.
Murat Alan 《代数通讯》2013,41(11):4089-4099
Let R be a commutative ring with identity. R is a finite factorization ring (FFR) if every nonzero nonunit of R has only a finite number of factorizations up to order and associates. In this article, we give a characterization of R for R[X] and R[[X]] to be an FFR. 相似文献
116.
Mahmut Akyiğit Hidayet Hüda Kösal Murat Tosun 《Advances in Applied Clifford Algebras》2013,23(3):535-545
Starting from ideas given by Horadam in [5] , in this paper, we will define the split Fibonacci quaternion, the split Lucas quaternion and the split generalized Fibonacci quaternion. We used the well-known identities related to the Fibonacci and Lucas numbers to obtain the relations between the split Fibonacci, split Lucas and the split generalized Fibonacci quaternions. Moreover, we give Binet formulas and Cassini identities for these quaternions. 相似文献
117.
Murat Adivar 《Mathematica Slovaca》2013,63(4):817-828
By means of the shift operators we introduce a new periodicity concept on time scales. This new approach will enable researchers to investigate periodicity notion on a large class of time scales whose members may not satisfy the condition there exists a P > 0 such that $t \pm P \in \mathbb{T}$ for all $t \in \mathbb{T}$ , which is being currently used. Therefore, the results of this paper open an avenue for the investigation of periodic solutions of q-difference equations and more. 相似文献
118.
The purpose of this article is to introduce an implicit iteration process for approximating common fixed points of three finite families nonexpansive mappings and to prove weak and strong convergence theorems in uniformly convex Banach spaces. 相似文献
119.
120.
The epoxy resins containing imine bonding were prepared from hydroxyl substituted Schiff base monomers in two steps. At the first step, hydroxyl substituted Schiff base monomers were synthesized via condensation reaction. At the second step, epoxy resins were synthesized from the reaction between Schiff base monomers and epichlorohydrine (EPC). Then curing processes of epoxy resins were achieved by p-phenylenediamine compound. The structures of resulting compounds were confirmed by FT-IR, UV-Vis and 1H-NMR. TG-DTA and DSC measurements were performed for thermal characterizations of the compounds. Chemical resistances of the cured epoxy-amine systems were determined for coating applications in acidic, alkaline and organic solvents. HCl (10%, aqueous solution), NaOH (10%, aqueous solution), DMSO, DMF, N-methylpyrrolidone, ethanol, THF and acetone were used for corrosion tests. Chemical resistance data of the synthesized epoxy resins demonstrated that they have good chemical resistance against various acid, alkaline and common organic solvents. Surface morphologies of epoxy resin and the cured epoxy resin were determined with scanning electron microscopy (SEM) measurements. Also, optical band gap (Eg) values of Schiff base monomers and epoxy resins were calculated from UV-Vis measurements. 相似文献