I. Dünya Savaşın'da Müslüman Halkın Rus İşgalinden Kaçışı ve Yaşamları (1914-1918)

Kafkas Cephesi’nde Rus ordusuyla girişilen mücadele Anadolu’nun doğusunu ve tüm savaş sahasının kaderini belirledi. Rus ilerleyişinin durdurulamaması ve Türk ordusunun geri çekilmesi beraberinde Müslüman ahalinin batıya doğru kitleler halinde göç etmesine neden oldu. Tüm varlıklarını Ruslara terk etmek mecburiyetinde kalan savunmasız bu insanlar, hayatlarını kurtarmak ve esarete düşmemek adına yurtlarını arkalarında bırakmak zorunda kaldı. Plansız ve hazırlıksız başlayan bu muhaceret, bölgenin zor iklim koşulları ve yetersiz ulaşım imkânları sebebiyle trajik bir manzara ortaya çıkardı. Bu çalışmada Rus işgal bölgelerinden hicret etmek zorunda kalan Müslüman ahalinin göç süreci ele alınmıştır. Yaşanan dram ağırlıklı olarak, hafıza kayıtlarının ışığında değerlendirilmeye çalışılmıştır.</p

Influence of Tb4O7 on structural, optical and gamma, charged particle and neutron shielding properties B2O3-Bi2O3-Na2O-Al2O3 glass system

The present study investigates the structural, optical, and radiation shielding properties against gamma rays, charged particles, and neutrons of the (75-x)B2O3 + 10Bi2O3 + 5Na2O + 10Al2O3 + xTb4O7 (x = 0, 1, 2, 3, 4 mol%) glass system. Experimental measurements included mass and linear attenuation coefficients (MAC and LAC), mean free path (MFP), half-value layer (HVL), and neutron absorbed dose rates. Theoretical calculations of shielding parameters were performed using EpiXS software. Additionally, mass stopping power and projected ranges for protons and alpha particles were obtained via the SRIM program. Raman spectroscopy revealed the vibrational modes, elucidating the molecular structure and bonding. UV-Vis spectroscopy assessed optical absorption and transparency, essential for applications requiring specific light transmission. FT-IR analysis identified various functional groups and bonding patterns. Both FT-IR and Raman results confirmed complex structural features, including Bi-O-Bi linkages in [BiO6] units, B-O-B connections, metaborate chains, and borate rings, highlighting the structural diversity of borate and bismuth groups. UV-Vis analysis showed direct and indirect band gaps ranging from 2.19 to 2.68 eV and 1.67-2.03 eV, respectively. The refractive index varied between 2.48 and 2.65, while the optical dielectric constant ranged from 5.15 to 6.02, indicating excellent optical transmission and structural compactness. It is noteworthy that incorporating 1 mol% Tb4O7 resulted in a 20.47 % enhancement of the MAC at 59.54 keV, while the increase was marginal-only 3.52 %-at 609.3 keV. When the concentration was raised to 4 mol%, the improvements reached 97.4 % at 59.54 keV and 8.45 % at 609.3 keV. These findings demonstrate that increasing Tb4O7 content significantly enhances the gamma shielding efficiency of the glass samples

BaF2-doped borosilicate glasses for next-generation radiation shielding and optical applications: A hybrid experimental and computational study

BaF2-doped borosilicate glasses were produced using the melt-quenching method with compositions of (56-x)B2O3 + 12SiO2 + 20CaO + 12Li2O + xBaF2 (x = 0, 2.5, 5, 7.5, and 10 mol%). The impact of BaF2 on the structural, optical, and radiation shielding characteristics was examined through experimental techniques and computational modelling. Density measurements indicated an increase from 2.2138 g/cm3 (BSCLB0) to 2.6549 g/cm3 (BSCLB10), attributed to the higher density of BaF2. Optical analysis revealed that the incorporation of BaF2 significantly altered the glass properties. The UV absorption edge shifted toward shorter wavelengths, decreasing the cut-off wavelength from 362.59 nm (BSCLB0) to 338.82 nm (BSCLB10), which suggests enhanced transparency in the UV region. The optical band gap energy for direct transitions increased from 3.835 eV to 4.145 eV, indicating a more compact glass structure. Meanwhile, the refractive index (n) declined from 1.769 (BSCLB0) to 1.558 (BSCLB10), demonstrating that BaF2 enhances optical clarity but may not be ideal for applications requiring a high refractive index. Additionally, the extinction coefficient (k) decreased, signifying reduced optical losses. The Urbach energy (EU), which reflects structural disorder, rose from 0.883 eV to 1.004 eV, implying slight modifications in the glass network due to BaF2 doping. The radiation shielding potential of BaF2-enriched borosilicate glasses was assessed using Monte Carlo simulations, EpiXS software, and Artificial Neural Networks (ANNs). The mass attenuation coefficient (MAC) exhibited a rise from 5.700 cm2/g (BSCLB0) to 17.093 cm2/g (BSCLB10) at 15 keV, indicating superior photon attenuation. Furthermore, the half-value layer (HVL) declined from 2.95 cm to 2.65 cm at 50 keV, confirming improved shielding performance. Glasses with higher BaF2 content displayed elevated effective atomic numbers (Zeff), reaching approximately 50 at 40 keV, which helps in minimizing secondary radiation generation. In terms of neutron shielding, the removal cross-section (ΣR) showed a modest increase, reaching 0.0956 cm−1 for BSCLB10, making these glasses comparable to boron carbide and graphite in neutron attenuation. These findings suggest that BaF2-doped borosilicate glasses are promising candidates for dual-purpose shielding applications, effectively attenuating both gamma rays and neutrons in nuclear and medical environments