The study conducted in the northwest region of Jordan aimed to assess the levels of natural radioactivity in soil and olive mill pomace (OMP) samples. The researchers used Nal (TI) gamma-ray spectrometry to measure the activity concentrations of ²²⁶Ra, ²³²Th, ⁴⁰K, and ¹³⁷Cs in the samples. The average activity concentrations of ²²⁶Ra, ²³²Th, ⁴⁰K, and ¹³⁷Cs in the soil samples were found to be 18.624 ± 5.82, 12.276 ± 5.728, 518.33 ± 212.57, and 0.140 ± 0.09 ($Bq,{\mathrm{kg}}^{-1}$), respectively. In the OMP samples, the average activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K were 7.272 ± 4.386, 3.454 ± 1.503, and 169.997 ± 81.873 ($Bq{\mathrm{kg}}^{-1}$), respectively, and no ¹³⁷Cs was detected. The study also investigated fundamental parameters associated with radon, specifically the radon emanation coefficient ($R{n}_{EC}$) and radon mass exhalation rate ($E_x$). The $R{n}_{EC}$ values ranged from 0.621 to 0.78 ($Bq{\mathrm{kg}}^{-1}$), with an average value of 0.71 ± 0.06 ($Bq{\mathrm{kg}}^{-1}$). The estimated $E_x$ from the soil samples ranged from 65.83 to 124.86 ($mBq{\mathrm{kg}}^{-1}{\mathrm{h}}^{-1}$), with an average value of 99.74 ± 21.73 ($mBq{\mathrm{kg}}^{-1}{\mathrm{h}}^{-1}$). Regarding radiological hazards, the study examined various parameters, including radium equivalent activity, external and internal hazard indices, gamma and alpha indices, absorbed gamma dose rate, and excess lifetime cancer risk. All of these assessed values were found to be below the worldwide recommended limits for radiological safety. Additionally, the study analyzed the concentrations of gross alpha and gross beta radioactivities in soil and OMP samples. The soil samples had an average gross alpha activity of 4.642 ± 1.04 ($Bq{\mathrm{kg}}^{-1}$) and an average gross beta activity of 48.13 ± 14.50 ($Bq{\mathrm{kg}}^{-1}$). The OMP samples showed an average gross alpha activity of 0.32 ± 0.27 ($Bq{\mathrm{kg}}^{-1}$) and an average gross beta activity of 59.19 ± 12.94 ($Bq{\mathrm{kg}}^{-1}$). Overall, the obtained results are crucial for evaluating the radiological risks associated with natural radioactivity in the northwest region of Jordan. The findings establish baseline data for comparison and reference for radioactivity levels in the environment.

We investigated the influence of transition metal coordination on the optical dispersion and thermo-optic behavior of the ionic liquid 1-butyl-3-methylimidazolium thiocyanate ([BMIM][SCN]). Refractive index measurements in the visible–near-infrared range (400–1000 nm), combined with temperature-dependent characterization (298–323 K), demonstrate that coordination with Al³⁺, Cd²⁺, Zn²⁺, and Mn²⁺ consistently increases the refractive index relative to the neat ionic liquid. All systems exhibit normal dispersion, following the hierarchy n(Al) > n(Cd) ≳ n(Zn) > n(Mn) > n([BMIM][SCN]), which reflects cooperative contributions from metal-centerd polarizability and coordination-induced modifications to density and electronic structure. Negative thermo-optic coefficients are measured for all samples, with [BMIM]₃[Al(SCN)₆] displaying the highest temperature sensitivity. Abbe diagrams and group-velocity dispersion analyses confirm a predictable index–dispersion trade-off and show that dispersion-related transport parameters are less temperature dependent than n(T). Collectively, these findings establish a structure–property framework for tuning refractive index, chromatic dispersion, and thermo-optic response via coordination chemistry, supporting the targeted design of thiocyanate-based ionic liquids for photonic components, thermal lenses, and dispersion-managed optical devices.