Sürdürülebilir Kalkınma Amaçları

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• MakaleAçık Erişim2019/r/munzur/5191
  Comparison of the public and private university campusses in Turkey in terms of the sustainable – ecological parameters

  Askin, Ali; Kaya, Sema Kayapinar; Dal, Murat

  In this study, it is aimed to highlight the properties of the increasing number of the university campusses in Turkey in terms of sustainable and ecological properties. 5 public (Boğaziçi, Bülent Ecevit, Karabük, İstanbul Teknik, Ege) and 5 private (Özyeğin, Yeditepe, Bahçeşehir, Bilgi and Bilkent) universities are investigated in terms of sustainable and ecological campus criterias such as “Energy Management”, “Sustainable Transportation”, “Waste Management”, “Water Management”, “Environmental Management” and “Sustainable Education”.

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  AtıfOpenAlex13·TR Dizin9

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• MakaleYalnız künye2019Scopus SJRQ2/r/munzur/3732
  Comprehensive study on the structural, optical, physical and gamma photon shielding features of B2O3-Bi2O3-PbO-TiO2 glasses using WinXCOM and Geant4 code

  Sayyed, M.I.; El-Mesady, I.A.; Abouhaswa, A.S.; Askin, A.; Rammah, Y.S.

  Glass samples of titanium-lead bismuth borate with the composition of (60B2O3 – 20Bi2O3 – (20-x)PbO – xTiO2), where 0 ≤ x ≤ 10 wt% labeled as BBPT0.0 (x = 0) to BBPT10.0 (x = 10) were synthesized. The melt quenching technique was used in the preparation. The amorphous character and vibrational groups for all samples were confirmed through XRD and FTIR measurements, respectively. The optical band gap (Eopt), Urbach's energy (Eurbach), and the optical dispersion constants have been determined using UV–Vis spectra. Results reveal that the values of the optical band gap energy exhibit a decrease with the TiO2 concentration, in contrast with Urbach's energy which displays a linear increase from 0.43 to 0.64 eV. In addition, the values of single-oscillator energy (Eo) has the same behavior of the optical energy gap (Eopt), while the dispersion energy parameter (Ed) has an inversely behavior. Mass attenuation coefficients (μ/ρ) of the investigated glasses have been computed using the Geant4 simulation toolkit and WinXCOM database software. Geant4 model of a HPGe detector has been employed to perform the Monte Carlo simulations for the glass samples with five thicknesses from 1 to 3 cm at the gamma ray energies in the range of 356–2510 keV. The transmission fractions as a function of the thickness at 356 keV photon energy for all studied glasses has been performed. Half value layer (HVL) was derived from the μ/ρ values. Results showed the studied glasses have good shielding capability according to their mass attenuation coefficients, transmission fractions and HVL values.

  AtıfScopus140·WoS136·OpenAlex144

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• MakaleYalnız künye2019Scopus SJRQ1/r/munzur/3693
  Investigation ofthe gamma ray shielding parameters of (100-x)[0.5Li2O–0.1B2O3–0.4P2O5]-xTeO2 glasses using Geant4 and FLUKA codes

  Aşkın, A.; Sayyed, M.I.; Sharma, Amandeep; Dal, M.; El-Mallawany, R.; Kaçal, M.R.

  In the present work, the radiation shielding proeprties of lithium borophosphtellurite glass system with the composition of (100-x) [0.5Li2O-0.1B2O3–0.4P2O5]-xTeO2 (x = 0, 10, 20, 30 and 40 mol%) were reported. The mass attenuation coefficient (μ/ρ) of the selected glass system (LiBPTe0, LiBPTe10, LiBPTe20, LiBPTe30 and LiBPTe40) was calculated at 356 keV, 662 keV, 1173 keV and 1330 keV photon energies by using Geant4 and FLUKA codes and the results were compared to the values obtained theoretically using WinXcom software. The correlation theory has been used to calculate the correlation coefficients (R2) between the results from WinXcom and the both simulations codes (Geant4 and FLUKA) for each sample. Moreover, some other radiation shielding parameters such as effective atomic number, photon transmission, mean free path and half value layer were calculated. The gamma photon transmission results showed that the transmission values of the 356 keV photons are lower than those of energies 662, 1173 and 1330 keV. At 356 keV, the transmission value for LiBPTe0 (at 6 cm thickness) is found to be 0.245 while at the same energy and thickness the transmission value is 0.088 for LiBPTe40. Out of all the glasses considered in present work, LiBPTe40 possesses the highest values of effective atomic number (Zeff). The Zeff values for the present glasses are 8.02, 9.55, 11.16, 12.85 and 14.64 for LiBPTe0, LiBPTe10, LiBPTe20, LiBPTe30 and LiBPTe40 respectively at 356 keV. The mass attenuation coefficient and effetive atomic number results showed that utilization 40% mol of TeO2 significantly improves the gamma ray shielding properties of the selected glass system. The shielding effectiveness of the selected samples was compared with other reference materials namely two radiation shielding glasses and four concretes used in different shielding purposes in terms of the mean free path (MFP) at 356 keV. The results revealed that the MFP of RS-253-G18 is lower than LiBPTe0sample. Moreover, the MFP of ordinary concrete is higher than the MFP of all glasses under examination, thus the investigated tellurite glasses have better attenuation features than the ordinary concrete.

  AtıfScopus106·OpenAlex107

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• MakaleYalnız künye2019Scopus SJRQ2/r/munzur/3642
  Synthesis, physical, structural and shielding properties of newly developed B2O3–ZnO–PbO–Fe2O3 glasses using Geant4 code and WinXCOM program

  Rammah, Y.S.; Askin, A.; Abouhaswa, A.S.; El-Agawany, F.I.; Sayyed, M.I.

  New zinc lead borate glasses with (50B2O3–10ZnO–(40 − y) PbO)–yFe2O3: 0 ≤ y ≤ 10 wt%) composition were synthesized by the conventional melt-quench technique. The amorphous nature of the glasses was tested by using X-ray diffraction spectroscopy. FTIR spectra for the glasses were recorded in the range of 4000–400 cm−1. Physical properties of the proposed glasses were evaluated. The mass attenuation coefficients (μ/ρ) for the glasses were calculated by the Geant4 simulation toolkit code and XCOM software within the photon energy range 365–2510 keV. Different γ-ray shielding parameters such as half-value layer, tenth value layer, and transmission fraction for the proposed glasses were evaluated using the obtained values of the (μ/ρ). Results reveal that for 1 cm glass thickness, the (50B2O3–10ZnO–30PbO)–10Fe2O3 sample has the highest transmission, due to the lower amount of Pb, and thus poorer shielding capability among the other glass samples. In addition, the probabilities of γ-ray interaction with the studied glasses were investigated.

  AtıfScopus62·OpenAlex64

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• MakaleYalnız künye2019Scopus SJRQ3/r/munzur/3411
  Assessment of the mass attenuation coefficients of granite, basalt, andesite and tuff stones with the Geant4 model of a high-purity germanium detector

  Aşkin, A.; Dal, M.

  In this work, the radiation shielding properties of various natural stones, such as granite, basalt, andesite and tuff, were determined by using Monte-Carlo simulations performed with the Geant4 model of a high-purity germanium (HPGe) detector. Mass attenuation coefficients were calculated for γ-ray energies of 80.9, 140.5, 356.5, 661.6, 1173.2 and 1332.5 keV and for the sample thicknesses between 1 and 7 cm. The results of this study indicate that the stone samples have lower mass attenuation values varying in the range from - 28.8 % to - 3.7 % compared to lead. Among the measured stone samples, the mass attenuation values of tuff stone are closest to lead (above 661.6 keV).

  AtıfScopus7·WoS6·OpenAlex8

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• MakaleAçık Erişim2019Scopus SJRQ1/r/munzur/3377
  An investigation on physical, structural and gamma ray shielding features of Dy3+ ions doped Telluroborate glasses

  Sathiyapriya, G.; Marimuthu, K.; Sayyed, M.I.; Askin, A.; Agar, O.

  Structural, physical and gamma ray shielding properties of Dy3+ doped telluroborate glasses have been discussed. The molar volume of the glasses is proportional to the TeO2 content. The FTIR studies investigate the expansion of TeO2 content and the dynamic change of tetrahedral [BO4] units into trigonal [BO3] units. Using the absorption spectra, optical band gap (Eg) and Urbach's energy (ΔE) values are calculated. The molar volume of oxygen (VO) and boron‑boron separation (<dB–B>) values are increasing while there is a fall in oxygen packing density (OPD) from 0% to 40% of TeO2. The ionic nature of the present glasses is analyzed from the bonding parameter (δ), optical basicity (Λth), covalent and ionic characteristic factors. The gamma photon attenuation investigated employing GEANT4 code. The transmission factor (TF) shows that 0TBD sample (0 wt% of TeO2) has the highest TF, while the 4TBD sample (40 wt% of TeO2) has the lowest TF.

  AtıfScopus42

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• MakaleYalnız künye2019Scopus SJRQ2/r/munzur/3334
  Physical, structural, optical, and radiation shielding properties of B2O3–Gd2O3–Y2O3 glass system

  Al-Hadeethi, Y.; Sayyed, M.I.; Kaewkhao, J.; Askin, A.; Raffah, Bahaaudin M.; Mkawi, E.M.; Rajaramakrishna, R.

  In the current paper, glass samples were prepared from the composition xGd2O3–(30-x)Y2O3–70B2O3 (where x = 5, 10, 15, 20 and 25 mol%) via the technique of melt-quenching. Various optical parameters and inter-atomic separation were evaluated for the fabricated samples. The results showed that the inter-substitution of Y2O3 content in replacement with Gd2O3 content in the glass matrix shows structural variation in the glass. The density increases from 3.5521 to 4.1613 g/cm3 with increase in Gd2O3 content that signifies the role of Gd2O3 being a glass modifier. The transmission spectra of the glass sample show more than 85% transmittance suggesting their superior transparency in the visible region. Also, several important shielding parameters of the prepared glass system have been computationally determined via the Geant4 model and the results were compared with Phy-X/PDS database software. The results revealed that the mass attenuation factor (µ/ρ) obtained by utilizing the two different toolkits are in agreement. The transmission fraction and the half value layer parameters of the glass system indicate that the glass sample with higher Gd concentration provides a better gamma blocking ability thanks to the high atomic number of Gd.

  AtıfScopus31·OpenAlex29

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• MakaleYalnız künye2019Scopus SJRQ1/r/munzur/3316
  Extensive study of newly developed highly dense transparent PbO-WO3-BaO-Na2O-B2O3 glasses for radiation shielding applications

  Sayyed, M.I.; Aşkın, A.; Ali, Atif Mossad; Kumar, Ashok; Rashad, M.; Alshehri, Ali M.; Singh, Mandeep

  Amorphous PbO – WO3 – BaO – Na2O – B2O3 glass system have fabricated using traditional melt quenching method. The XRD and FTIR spectra confirm the amorphous nature and the various structural properties of the glasses respectively. The various optical properties have been measured in the spectral range 400–4000 cm−1. Also, to understand the shielding ability of the fabricated glasses, we used the Geant4 model of a HPGe detector and WinXcom program to calculate the mass attenuation coefficient (MAC) at six energies between 356 and 2510 keV. In order to confirm the agreement between both methods, we used correlation theory and calculated the correlation coefficients (R2) for each sample. It is found that the R2 values are close to 1 for all samples. The MAC values at 356 keV for the prepared samples lies between 0.221 and 0.246 cm2/g. It is found that the usage of different concentration of PbO (from 50 to 70 mol%) affects the MAC values and thus the attenuation ability of the samples due to the heavier density of the PbO in comparison to B2O3. The effective atomic number results showed that Pb70B10 sample (contains 70 mol% of PbO) was higher than the other samples. Hence, Pb70B10 absorbs more photons than the rest of the prepared glasses.

  AtıfScopus33·OpenAlex33

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• Derleme MakaleAçık Erişim2018/r/munzur/5279
  Yapılarda kullanılan malzemelerden yayılan doğal radyasyonun araştırılmasına yönelik çalışmalar

  Askin, Ali; Dal, Murat

  Bu derlemede, çeşitli yapı malzemelerinde var olan 226Ra, 232Th, 40K radyoaktif izotoplarından yayılan gama radyasyonun aktivitesinin ve bu aktivitelere bağlı olan radyum eşdeğer aktivitesi, gama ve alfa indeksi, soğurulan gama doz oranı ile iç ve dış risk indeksleri gibi radyolojik parametrelerinin belirlenmesi amacıyla Türkiye’de ve diğer ülkelerde yapılmış araştırmalar ve sonuçları incelenerek okuyucuların dikkatine sunulmuştur. Yapılan çalışmaların genelinde granit ve kum örneklerindeki doğal radyoaktivite diğer malzemelere oranla daha yüksek bulunmuştur. Aktivitesi yüksek bulunan bazı çimento örneklerinde, yüksek radyoaktivtenin kaynağının çimentoda katkı malzemesi olarak kullanılan kül’den kaynaklandığı belirtilmiştir. Bu konuda yapılan çalışmaların sayıları ve elde edilen sonuçlar değerlendirildiğinde, yapı malzemelerinden yayılan doğal radyoaktivitenin belirlenmesinin uzun vadede insan sağlığının korunmasına önemli katkıları olacağı görülmektedir.

  AtıfOpenAlex1

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