Photoreactivity, Optical Behavior and DFT Studies of 2,5-Bis[4-choloro-acetyl(thiophen-2-ylmethylene)]cyclopentanone BCTCP in Different Solvents.

Diarylidenecyclopentanone compound namely, 2,5-bis[4-choloroacetyl-(thiophen-2-ylmethylene)]cyclopentanone (BCTCP) was firstly synthesized using the normal condition of Friedel-Crafts method by reacting 2,5-bis(thiophen-2-ylmethylene)cyclopentanone (BTCP) with chloroacetyl chloride in the presence of aluminum chloride anhydrous. The structure of this compound was confirmed by elemental and spectral analyses including FT-IR, 1H-NMR, 13C-NMR and mass spectrometry. The electronic absorption and emission properties of BCTCP were studied in different solvents. BCTCP displays a slight solvatochromic effect of the absorption and emission spectrum, indicating a small change in dipole moment of BCTCP upon excitation. BCTCP displayed photodecomposition in chlorinated solvents upon irradiating with 365 nm light. Ground and excited states electronic geometric optimizations were performed using density functional theory (DFT) and time-dependent density functional theory (TD-DFT), respectively. A DFT natural bond orbital (NBO) analysis complemented the intramolecular charge transfer (ICT). The simulated maximum absorption and emission wavelengths are in line the observed ones in trend, and were proportionally red-shifted with the increase of the solvent polarity. The stability, hardness and electrophilicity of BCTCP in different solvents were correlated with the polarity of the elected solvents.

Assessment of Committed Effective Dose due to consumption of Red Sea coral reef fishes collected from the local market (Sudan).

An assessment of Committed Effective Dose (CED) due to consumption of Red Sea fish containing (210)Po and (137)Cs was performed for 23 different marine fish samples collected from the local market at Port Sudan. The fish were classified according to their feeding habits into three categories: carnivores, herbivores, and omnivores. Measured activity concentrations of (210)Po were found in the ranges 0.25-6.42 (carnivores), 0.7-5 (omnivores) and 1.5-3.8 (herbivores) Bq/kg fresh weight. In the same study, activity concentrations of Cs-137 were determined to be in the ranges 0.1-0.46 (carnivores), 0.09-0.35 (omnivores) and 0.09-0.32 (herbivores) Bq/kg fresh weight, which were several times lower than those of (210)Po. Appropriate conversion factors were used to derive the CED, which was found to be 0.012, 0.01 and 0.01 (microSv/yr) in carnivores, omnivores and herbivores, respectively, for (137)Cs. This contributes about 0.4% of the total dose exclusively by ingestion of fish. For (210)Po, it was found to be 3.47, 4.81 and 4.14 (microSv/yr) in carnivores, omnivores and herbivores, respectively, which represents 99.6% of the total dose (exclusively by ingestion of fish). The results of CED calculations suggest that the dose received by the Sudanese population from the consumption of marine fish is rather small and that the contribution of (137)Cs is negligible compared to (210)Po.