Volume 108, Issue 10

In this work, a novel task specific ionic liquid (TSIL) [tributyl(hexyl)phosphonium] 2 [diglycolic acetate] ([P 6,4,4,4 ] 2 [DGA]) was prepared and used to construct a vesicle system. The addition of UO 2 2+ , La 3+ or Th 4+ exhibited different effects on the system. It was found that small amount of UO 2 2+ could induce large-sized aggregation of vesicles and make the precipitation happen, while La 3+ and Th 4+ did not have such capacity. The whole process was characterized by dynamic light scattering and freeze-fracture transmission electron microscopy. An extraction-precipitation strategy was then developed for the selective recovery of UO 2 2+ . Different factors were further studied to optimize the separation efficiency of the extraction-precipitation process.

The study demonstrates the accomplishment of single step, direct supercritical fluid carbon dioxide (SC CO 2 ) dissolution and extraction of uranium from crude matrices viz. yellow cakes (>90%) and rock phosphate ores (70%) employing adducts of trialkyl phosphates and nitric acid, thus avoiding free acid usage and eliminating number of process steps. Rock phosphate ore was made amenable for supercritical fluid extraction (SFE) system by unique strategy of pyrohydrolytic removal of fluorine. Pressure and temperature conditions, which were found to influence uranium extraction efficiency, were optimized at 150 atm. and 323 K. Two milliliter of adduct amount was found to be adequate. Adducts of branched alkyl phosphate, tri-isoamyl phosphate and tri-ethyl hexyl phosphate (TEHP), yield better purity in comparision to straight chain tri-butyl phosphate (TBP).

This paper reports volatilization behavior of RuO 4 from nitric acid medium using UV–Vis spectroscopy. Ruthenium (III) solution was oxidized to Ru (VIII) using potassium metaperiodate. The absorption peak of RuO 4 at 385 nm was used to measure Ru(VIII) concentration in solution. The volatilization kinetics has been studied at different temperature and used to derive rate constant and activation energy values. Almost 82% Ruthenium (VIII) has been volatilized from nitric acid medium at 70 °C whereas it is only 15% at 25 °C. Effect of different parameters like temperature, potassium metaperiodate concentration and nitric acid concentration on volatilization has been studied in depth and reported in this paper.

In this paper, sugarcane bagasse (SCB) was modified using phosphoric acid. The modified sugarcane bagasse (MSCB) has been used to remove 4-(2-pyridylazo)resorcinol (PAR) and Arsenazo-III (Ar-III) from liquid radioactive waste. The surface morphology and functional groups of the MSCB were studied using scanning electron microscopy (SEM), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Adsorption ability of MSCB has been tested by batch mode through some relevant factors like initial pH, reaction time, initial coloring reagents (PAR and Ar-III) concentrations, and adsorbent weight. At adsorption equilibrium time 180 min and pH values of 3 and 1 for PAR and Ar-III; the maximum removal (%) for both PAR and Ar-III were 93 and 57%, respectively. The adsorption isotherm data are representative well to Freundlich isotherm model. The mean free energy of adsorption, E (kJ/mol), has been estimated as 5.75 and 2.28 kJ/mol for PAR and Ar-III, respectively, which suggests that the adsorption occurred physically. The maximum adsorption capacity of MSCB for PAR and Ar-III is 96.62 and 15.18 mg/g, respectively. The adsorption kinetics are better fitted by the pseudo-second-order model. The partial film along with intra-particle diffusion controlled the diffusion of coloring reagents from the solution bulk to the particle interior pores. Application of MSCB for removing PAR and Ar-III from simulated liquid radioactive waste containing U(VI) and Th(VI) ions has been achieved successfully.

Removal of 137 Cs radionuclides from the environment has engrossed the concern of researchers after Fukushima accident. The leakage of radioactive cesium ions can lead up to surface and groundwater contamination, and this leads to pollution of drinking water sources. In this work, corchorus olitorius stalks has been used as a novel precursor for production of low-cost meso porous a ctivated c arbon ( Meso-AC ) and HNO 3 /H 2 O 2 - m odified Meso-AC ( m-Meso-AC ). The physicochemical properties of all adsorbents were evaluated. The influences of sorption parameters and presence of some ligands (humic acid, fulvic acid, and EDTA) on the sorption of 137 Cs were studied. The maximum 137 Cs capacity of m-Meso-AC was found to be 58.74 mg/g. Efficiency of the new adsorbent to remove 137 Cs radionuclides from natural waters (tap, river, and groundwater) was investigated. The studies showed that new adsorbent could be used as promising material for the retention of 137 Cs from real radioactive waste and natural water samples.

Targeted drug delivery system can reduce the side effects of high drug concentration by improving drug pharmacokinetics at lower doses. Citrate-gold nanoparticles (AuNPs) as a drug delivery system were synthesized via green nanotechnology technique to be used as a new imaging platform for tumor targeting. Citrate-AuNPs were synthesized with core size of 10 nm. Citrate-AuNPs were labeled with technetium-99m ( 99m Tc) with radiochemical yield of 95.20 ± 2.70% with good in-vitro stability in both saline and human serum and well in-vivo studied in both normal and solid tumor bearing mice. The in-vivo biodistribution study of [ 99m Tc]Tc-citrate-AuNPs in solid tumor bearing mice (as preliminary study) showed a high accumulation in tumor site with tumor/muscle of 4.35 ± 0.22 after 30 min post injection. The direct intratumoral (I.T) injection of [ 99m Tc]Tc-citrate-AuNPs showed that this complex was retained in the tumor up to 77.86 ± 1.90 % at 5 min and still around 50.00 ± 1.42 % after 30 min post injection (p.i.). The newly presented nano-platform could be presented as a new potential radiopharmaceutical tumor imaging probe.

Most of the rural Algerian communities believed that Pistacia lentiscus L . leaves have therapeutic capacities to treat many gastric diseases and abdomen aches, whereas, the rural habitants of Mitidja, Algeria powdered P. lentiscus L. leaves and consume it fresh in order to heal mild dyspeptic disorders and peptic ulcer. Therefore, the current study was conducted to investigate and monitor the amount of essential and toxic elements of these leaves. The leaf samples were collected from a place called Mitidja, Algeria in autumn 2014. Thereafter, those samples were subjected to an instrumental neutron activation analysis (INAA). Fourteen elements were assessed (As, Br, Ca, Co, Fe, K, La, Na, Rb, Sb, Sc, Sm, Th and Zn). Where, the elements Ca, Fe, K, Na and Zn presented significant concentrations. On the other hand, it was found that the tolerable daily intake (TDI) of these leaves for an adult person per day, is with the tolerance limits and satisfy the nutritional references. Moreover, P. lentiscus L. leaves might be an important nature supplier source of Ca, K, Na, Fe and Zn for the human body, since these elements are considered as the most dietary supplements recommended by doctors to maintain good health.

Thanks to its rich content, propolis has been used to protect the hive from all kinds of external influences and for disinfection by bees. Furthermore, it is an important marker for monitoring environmental pollution because the main sources of propolis are plant and secretions. So, the present study aimed to research radiation attenuation capability and the natural radioactivity level of propolis samples. For this reason, both natural radioactivity concentrations ( 226 Ra, 232 Th and 40 K) and attenuation coefficients (Linear and Mass) in the propolis samples collected from 10 different points in Turkey were measured using high purity germanium detector (HPGe). The average natural radioactivity concentrations in samples were found to be 0.56 ± 0.19, 2.65 ± 0.31 and 70.08 ± 2.42 Bq/kg for 226 Ra, 232 Th and 40 K, respectively. These values were much lower than the average world values (35 Bq/kg for 226 Ra, 30 Bq/kg for 232 Th and 400 Bq/kg for 40 K) reported by United Nations Scientific Committee on Effects of Atomic Radiation (UNSCEAR) in foodstuff. The average linear attenuation coefficient, mass attenuation coefficients and half value layer values for gamma rays with 59.54 keV energy were determined as 0.1970 cm −1 , 0.1831 cm 2 g −1 and 3.56 cm, respectively. In addition, antioxidant properties of the samples were measured using total phenolic content and ferric reducing antioxidant power. Their correlations with radioactivity were investigated.