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 Journal of Environmental Protection (JEP) , 2014, DOI: 10.4236/jep.2014.53023 Abstract: The radium isotopes 226Ra and 228Ra were analyzed in surface water at six points in the neighborhood of a mine of phosphate, associated with uranium, in the region of Santa Quitéria, state of Ceará, Brazil. Water samples were collected during twenty months, filtered and the concentrations of activity determined in the soluble and particulate phases. The results were analyzed using the Principal Component Analysis (PCA) for ordination of environmental data, and also by ANOVA, Tukey and Z tests to compare sets of data considering the radionuclides, the two analyzed phases and the six collecting points. The PCA identified four groups that included all collecting points, using aggregation features such as radionuclide and analyzed phase. The first group is composed by the samples of 226Ra in the soluble phase; the second group by samples of 226Ra in the particulate phase; the third one by 228Ra in the soluble phase, and finally, the fourth group by 228Ra in the particulate phase. This last group has two discrepant points (01 and 06). Statistical analysis identified differences between the concentrations of activity of radionuclides (228Ra higher than 226Ra) and in analyzed phases (soluble phase higher than the particulate one) but showed no differences between sampled points.
 Physics , 2012, Abstract: Currently, thirty-nine astatine, thirty-nine radon, thirty-five francium, and thirty-four radium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.
 Journal of Environmental Protection (JEP) , 2016, DOI: 10.4236/jep.2016.79103 Abstract: An assessment of radiologically enhanced residual materials generated during oil and gas production in near Baku, Azerbaijan, was conducted. Distribution of the 228Ra/226Ra Activity Ratio (AR) with depth in a sediment core from radium lake was examined. The dashed line represented ingrowth assuming that 228Ra was below equilibrium with 232Th in the young sediments near the top and reached equilibrium at a depth around 10 cm. In this study the radium isotopic data are used to provide estimates of the age of formation of the radiobarite contaminant and age of oil field lake. The results indicate that, the upper two layers in the core (up to 4 cm) contain fallout 137Cs so at least these layers are no older than about 40 yrs. Formation waters that are sent to disposal ponds may consist of accumulated heavy hydrocarbons, paraffin, inorganic solids, and heavy emulsions. We report here results of chemical and radiochemical measurements from formation waters separated from oil pumped from approximately 700 m below ground near Baku, Azerbaijan. Our results also include data from a formation water storage pond (“radium lake”) where the waters are temporarily stored after oil is separated and then eventually disposed of by pumping into the Caspian Sea. We also analyzed the associated sediment for radiochemical components. Our study was intended to investigate how radium fractionated between the pond water and sediments.
 地球学报 , 2008, Abstract: This paper reports the results of initial research on radium isotopes of surface ocean waters in the Longjiao Bay on the western flank of Taiwan Strait. The main objective of this research is to assess the submarine groundwater discharge (SGD). In order to assess the spatial distribution of 224Ra and 226Ra, the authors collected 15 surface ocean water samples (ca. -1 m in depth) during the low tide. The collection was performed within a period of 2 hours in the direction from onshore to 9 km offshore by using 60 L polypropylene buckets. In the laboratory, the water samples were immediately treated through gravity-fed PVC column (4.5 cm in diameter, 50 cm in length), filled with manganese oxide-impregnated acrylic fiber at a flow rate of 300 ml/min to retain radium. After that, the activities of 224Ra absorbed on the Mn-fiber were measured through the continuous emanation method. Finally, the Mn-fiber was sealed for more than 7 days, and the activities of 226Ra absorbed on the Mn-fiber were measured through the direct emanation method. 226Ra distribution yields an activity gradient of -0.963 dpm100 l-1km-1. The short-lived 224Ra distribution in this region yields an eddy diffusion coefficient of 68.83 km2d-1. The interpretation is that the eddy diffusion is the primary controlling agent for the shore perpendicular distribution of the long-lived 226Ra. In order to estimate the seepage rate of groundwater in the study area, the authors applied the approach developed by Moore. The short-lived radium isotopes, 224Ra, were used to establish the eddy diffusion coefficient for the near-shore study area. The product of the eddy diffusion coefficient and the offshore 226Ra activity gradient established the 226Ra flux of 6.62×1011dpmkm-2d-1. It is expected that this flux must be balanced by Ra input from the submarine groundwater discharge (SGD). On the basis of the flux of SGD within the shore, 226Ra budget was calculated as 3.03×109 m3km-2d-1. This magnitude of SGD includes terrestrially-derived fresh SGD and recirculated seawater SGD, However, further researches should be required to determine the terrestrially-derived fresh SGD on the one hand, and recirculated seawater SGD on the other hand.
 Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2011, DOI: 10.4236/jasmi.2011.11001 Abstract: A method for determination of 226Ra and 228Ra in environmental samples using the α-β coincidence liquid scintillation counting (LSC) has been developed. Radium were preconcentrated from environmental samples by coprecipitation with BaSO4, then purified from others radionuclide interferences using the cation column exchange (Bio-Rad AG 50 W-X4 resin with 200-400 mesh size and H+ form) and operating in warm temperature which is between 70-80oC. Then, the Ba(Ra)SO4 precipitate was filtered through the Millipore filter paper, dried and weighed to calculate chemical yield. The activity concentration of radium isotopes in mixture of liquid scintillation cocktails were measured using LSC after being stored for over 21 days to allow the growth of the progeny nuclides. The method has been validated with a certi-fied reference material supplied by the International Atomic Energy Agency and reliable results were obtained. The radiochemical yields for radium were 59% - 90% and recovery was 97% and 80% for 226Ra and 228Ra, respectively. Sixteen seawater and fish flesh samples collected in Kapar coastal water have been analyzed with the developed method. The obtained radium activity concentrations in seawater were in the range of 02.08 ± 0.82 mBq/L to 3.69 ± 1.29 mBq/L for 226Ra and 6.01 ± 3.05 mBq/L to 17.07 ± 6.62 mBq/L for 228Ra. Meanwhile, the activity concentrations of 226Ra and 228Ra in fish flesh were in the range of 11.82 ± 5.23 – 16.53 ± 6.53 Bq/kg dry wt. and 43.52 ± 16.34 – 53.57 ± 19.86 Bq/kg dry wt., respectively.
 Nik Azlin Nik Ariffin EnvironmentAsia , 2010, Abstract: The concentration levels of natural radium isotopes such as 226Ra and 228Ra were measured in the atmospheric samples including rainwater, total suspended solids (TSSrw) and marine environment samples collected around the Kapar coal-fired power plant from September 2006 to February 2008. Activity concentration of 228Ra and 226Ra in rainwater showed the higher concentrations compared to the seawater. The mean activities of 226Ra and 228Ra in rainwater at Kapar were 20.45±4.50 mBq/L and 74.82±25.38 mBq/L, respectively. Meanwhile the levels in total suspended solids (TSSrw) of rainwater showed 226.99±52.57 Bq/kg for 226Ra and 439.92±186.17 Bq/kg for 228Ra. The measurements of radium isotopes concentration in rainwater at coal-fired power plant in Kapar are found in relation to their sources and application as tracers in lower atmosphere. The mean value of pH in rainwater during this study is pH 5.51 slightly acidic as lowest value for the standard of clean rainwater. Radium in seawater also strong adsorption onto total suspended solids with the distribution coefficient, Kd values of 228Ra and 226Ra ranged from 0.054 × 104 to 163.90 × 104 L/g and between 0.49 × 104 to 191.54 × 104 L/g, respectively.
 Physics , 2015, Abstract: Mean field calculations, based on the D1S, D1N and D1M parametrizations of the Gogny energy density functional, have been carried out to obtain the potential energy surfaces relevant to fission in several Ra isotopes with the neutron number 144 $\le$ N $\le$ 176. Inner and outer barrier heights as well as first and second isomer excitation energies are given. The existence of a well developed third minimum along the fission paths of Ra nuclei, is analyzed in terms of the energetics of the "fragments" defining such elongated configuration. The masses and charges of the fission fragments are studied as functions of the neutron number in the parent Ra isotope. The comparison between fission and $\alpha$-decay half-lives, reveals that the former becomes faster for increasing neutron numbers. Though there exists a strong variance of the results with respect to the parameters used in the computation of the spontaneous fission rate, a change in tendency is observed at N=164 with a steady increase that makes heavier neutron-rich Ra isotopes stable against fission, diminishing the importance of fission recycling in the r-process.
 Physics , 2009, DOI: 10.1016/j.nima.2009.05.007 Abstract: Short lived $^{212,213,214}$Ra isotopes have been produced at the TRI$\mu$P facility in inverse kinematics via the fusion-evaporation reaction $^{206}$Pb+$^{12}$C at 8 MeV/u. Isotopes are separated from other reaction products online using the TRI$\mu$P magnetic separator. The energetic radium (Ra) isotopes at the exit of the separator were converted into low energy ions with a thermal ionizer. Ra isotopes have been identified by observing their $\alpha$ decay and life times.