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The isotopic abundance and atomic weight of natural uranium
Yongfu Liu,Shuchun Fu
Chinese Science Bulletin , 1997, DOI: 10.1007/BF02882489
Abstract: The published measurement data of atomic weight of uranium are shown in table 4[9]. The best results are those measured by Smith and Cowanet al. A r (U) = 238.028 79–238.028 90(3), their result error being ISD. The evaluated value of IUPAC-CAWIA is Ar(U)=238.028 9(1). In this work, the result is Ar(U) = 238.028 91(4). The combined uncertainty has been given according to 2SD of the measurement data through the calibration of a series of standard materials of uranium isotopes. It is reasonable to conclude that in this work the uncertainty which characterizes the measurement quality is better than other published data.
Distribution of uranium, thorium, and isotopic composition of uranium in soil samples of south Serbia: Evidence of depleted uranium
Sahoo Sarata Kumar,Fujimoto Kenzo,?elikovi? Igor,Uji? Predrag
Nuclear Technology and Radiation Protection , 2004, DOI: 10.2298/ntrp0401026s
Abstract: Inductively coupled plasma mass spectrometry and thermal ionization mass spectrom - etry were used to measure concentration of uranium and thorium as well as isotopic composition of uranium respectively in soil samples collected around south Serbia. An analytical method was established for a routine sample preparation procedure for uranium and thorium. Uranium was chemically separated and purified from soil samples by anion exchange resin and UTEVA extraction chromatography and its isotopic composition was measured using a thermal ionization mass spectrometry. There was a little deviation of U/Th ratio from the average values in some soil samples. Presence of 236U as well as depleted uranium was observed in 235U/238U ratio measurement in the same soil sample.
Matrix contribution of environmental swipe materials for safeguard to uranium isotopic measurement  [cached]
Jong-Sik Ryu,Youn-Joong Jeong,Hyun-Ju Cha,Hyung Seon Shin
Journal of Analytical Science & Technology , 2010,
Abstract: In order to investigate and quantify uranium content and isotope ratios in environmental swipe materials itself, the determinations of uranium isotope ratios in cotton swipes as well as working standard solutions are performed using multi collector inductively coupled plasma mass spectrometer (MC-ICPMS) and thermal ionization mass spectrometer (TIMS). We found that co-existing uranium in the swipes causes a serious shift of the measured data from the certified values. This study highlights the importance of mass balance correction for a precise uranium isotopic measurement of environmental swipe materials.
Teratogenicity of depleted uranium aerosols: A review from an epidemiological perspective
Rita Hindin, Doug Brugge, Bindu Panikkar
Environmental Health , 2005, DOI: 10.1186/1476-069x-4-17
Abstract: We reviewed toxicological data on both natural and depleted uranium. We included peer reviewed studies and gray literature on birth malformations due to natural and depleted uranium. Our approach was to assess the "weight of evidence" with respect to teratogenicity of depleted uranium.Animal studies firmly support the possibility that DU is a teratogen. While the detailed pathways by which environmental DU can be internalized and reach reproductive cells are not yet fully elucidated, again, the evidence supports plausibility. To date, human epidemiological data include case examples, disease registry records, a case-control study and prospective longitudinal studies.The two most significant challenges to establishing a causal pathway between (human) parental DU exposure and the birth of offspring with defects are: i) distinguishing the role of DU from that of exposure to other potential teratogens; ii) documentation on the individual level of extent of parental DU exposure. Studies that use biomarkers, none yet reported, can help address the latter challenge. Thoughtful triangulation of the results of multiple studies (epidemiological and other) of DU teratogenicity contributes to disentangling the roles of various potentially teratogenic parental exposures. This paper is just such an endeavor.In aggregate the human epidemiological evidence is consistent with increased risk of birth defects in offspring of persons exposed to DU.Depleted uranium (DU) is a man-made, radioactive, heavy metal derived from uranium ore. Naturally occurring uranium ore (rock in which the uranium concentration is approximately 1,000 or more parts per million) is mined and processed to yield a much more concentrated substance, one that is virtually pure uranium. Natural uranium exists in three isotopic forms and contains 99.274% U238, 0.72% U235, and 0.0057% U234 by weight. DU, a byproduct of uranium enrichment, has an isotopic content of 99.75% U238, 0.25% U235, and 0.005% U234. As part of
Influence of Biofield Energy Treatment on Isotopic Abundance Ratio in Aniline Derivatives
Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Gunin Saikia, Snehasis Jana
Modern Chemistry & Applications , 2015, DOI: 10.4172/2329-6798.1000168
Abstract: The aim of this study was to evaluate the impact of biofield energy treatment on the isotopic abundance of 13C/12C or 2H/1H or 15N/14N ≡ (PM 1)/PM in aniline; and (PM 1)/PM and 81Br/79Br ≡ (PM 2)/PM in 4-bromoaniline using Gas Chromatography-Mass Spectrometry (GC-MS). Aniline and 4-bromoaniline samples were divided into two parts: control and treated. The control part remained as untreated, while the treated part was subjected to Mr. Trivedi’s biofield energy treatment. The treated samples were subdivided in three parts named as T1, T2, and T3 for aniline and four parts named as T1, T2, T3, and T4 for 4-bromoaniline. The GC-MS data revealed that the isotopic abundance ratio of (PM 1)/PM in aniline was increased from -40.82%, 30.17% and 73.12% in T1, T2 and T3 samples respectively. However in treated samples of 4-bromoaniline the isotopic abundance ratio of PM 1/PM was increased exponentially from -4.36 % (T1) to 368.3% (T4) as compared to the control. A slight decreasing trend of the isotopic ratio of (PM 2)/ PM in 4-bromoaniline was observed after biofield energy treatment. The GC-MS data suggests that the biofield energy treatment has significantly increased the isotopic abundance of 2H, 13C and 15N in the treated aniline and 4-bromoaniline, while slight decreased the isotopic abundance of 81Br in treated 4-bromoaniline as compared to their respective control.
The Abundance of Atomic Sulfur in the Atmosphere of Io  [PDF]
Lori M. Feaga,Melissa A. McGrath,Paul D. Feldman
Physics , 2002, DOI: 10.1086/339500
Abstract: Observations with the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope have been used to constrain the atomic sulfur column density in Io's atmosphere. The SI 1479 dipole allowed and forbidden transition multiplets have been resolved for the first time at Io, enabling the study of both optically thick and thin transitions from a single atomic species. The allowed transitions contribute 62 +/- 8% and the forbidden transitions 38 +/- 8%, on average, to the total signal of the SI 1479 multiplets. Using the optically thick and thin transitions of SI 1479 observed near the limbs of Io, we derive a tangential atmospheric sulfur column abundance of 3.6*10^12 cm^-2 < N_s < 1.7*10^13 cm^-2, which is independent of electron temperature and density. A low density SO_2 atmosphere, N_so2 ~ 5-10*10^15 cm^-2, consistent with that inferred from other recent observations, is most consistent with these bounds.
Evaluation of Isotopic Abundance Ratio in Naphthalene Derivatives After Biofield Energy Treatment Using Gas Chromatography-Mass Spectrometry
Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Gunin Saikia, Snehasis Jana
American Journal of Applied Chemistry , 2015, DOI: 10.11648/j.ajac.20150306.13
Abstract: Naphthalene and 2-naphthol are two naphthalene derivatives, which play important roles in the chemical and pharmaceutical industries. The aim of this study was to evaluate the impact of biofield energy treatment on the isotopic abundance of 13C/12C or 2H/1H and 18O/16O in naphthalene and 2-naphthol using gas chromatography-mass spectrometry (GC-MS). Naphthalene and 2-naphthol samples were divided into two parts: control and treated. The control group remained as untreated, while the treated group was subjected to Mr. Trivedi’s biofield energy treatment. The treated samples were subdivided into four parts named as T1, T2, T3 and T4. Control and treated samples were characterized using GC-MS. The GC-MS data revealed that the isotopic abundance ratio of 13C/12C or 2H/1H, (PM 1)/PM and 18O/16O, (PM 2)/PM were increased significantly in treated naphthalene and 2-naphthol (where PM-primary molecule, (PM 1) isotopic molecule either for 13C or 2H and (PM 2) is the isotopic molecule for 18O). The isotopic abundance ratio of (PM 1)/PM in the treated T2 samples of naphthalene and 2-naphthol was increased up to 129.40% and 165.40%, respectively as compared to their respective control. However, the isotopic abundance ratio of (PM 1)/PM in the treated T1, T3 and T4 samples of naphthalene was decreased by 44.41%, 33.49% and 30.3%, respectively as compared to their respective control. While in case of 2-naphthol, the isotopic abundance ratio of (PM 1)/PM was decreased by 39.57% in T1 sample and then gradually increased up to 9.85% from T3 to T4 samples. The isotopic abundance ratio of (PM 2)/PM in treated T2 sample of 2-naphthol was increased up to 163.24%, whereas this value was decreased by 39.57% in treated T1 sample. The GC-MS data suggest that the biofield energy treatment has significantly altered the isotopic abundance of 2H, 13C in naphthalene and 2H, 13C and 18O in 2-naphthol as compared to the control.
Investigation of Isotopic Abundance Ratio of Biofield Treated Phenol Derivatives Using Gas Chromatography-Mass Spectrometry
Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Jana S
Journal of Chromatography & Separation Techniques , 2015, DOI: 10.4172/2157-7064.S6-003
Abstract: Butylatedhydroxytoluene (BHT) and 4-methoxyphenol (4-MP) are phenol derivatives that are generally known for their antioxidant properties and depigmenting activities. The aim of this study was to evaluate the impact of biofield energy treatment on the isotopic abundance in BHT and 4-MP using gas chromatography-mass spectrometry (GC-MS). BHT and 4-MP samples were divided into two parts: control and treated. The control group remained untreated while the treated group was subjected to Mr. Trivedi’s biofield treatment. Control and treated samples were characterized using GC-MS. The GC-MS data revealed that the isotopic abundance ratio of?13C/12C or?2H/1H(PM 1)/PM and?18O/16O (PM 2)/PM increased significantly in treated BHT and 4-MP (where PM- primary molecule, PM 1- isotopic molecule either for?13C or?2H and PM 2 is the isotopic molecule for?18O). The isotopic abundance ratio of (PM 1)/PM in the treated BHT and 4-MP was increased up to 181.27% and 380.73% respectively as compared to their respective control. Moreover, the isotopic abundance ratio of (PM 2)/PM in the treated BHT and 4-MP increased up to 185.99% and 355.33% respectively. GC-MS data suggests that the biofield treatment significantly increased the isotopic abundance of?2H,?13C and?18O in the treated BHT and 4-MP as compared to the control.
Silicon isotopic abundance toward evolved stars and its application for presolar grains  [PDF]
T. -C. Peng,E. M. L. Humphreys,L. Testi,A. Baudry,M. Wittkowski,M. G. Rawlings,I. de Gregorio-Monsalvo,W. Vlemmings,L. -A. Nyman,M. D. Gray,C. de Breuck
Physics , 2013, DOI: 10.1051/0004-6361/201322466
Abstract: Galactic chemical evolution (GCE) is important for understanding the composition of the present-day interstellar medium (ISM) and of our solar system. In this paper, we aim to track the GCE by using the 29Si/30Si ratios in evolved stars and tentatively relate this to presolar grain composition. We used the APEX telescope to detect thermal SiO isotopologue emission toward four oxygen-rich M-type stars. Together with the data retrieved from the Herschel science archive and from the literature, we were able to obtain the 29Si/30Si ratios for a total of 15 evolved stars inferred from their optically thin 29SiO and 30SiO emission. These stars cover a range of masses and ages, and because they do not significantly alter 29Si/30Si during their lifetimes, they provide excellent probes of the ISM metallicity (or 29Si/30Si ratio) as a function of time. The 29Si/30Si ratios inferred from the thermal SiO emission tend to be lower toward low-mass oxygen-rich stars (e.g., down to about unity for W Hya), and close to an interstellar or solar value of 1.5 for the higher-mass carbon star IRC+10216 and two red supergiants. There is a tentative correlation between the 29Si/30Si ratios and the mass-loss rates of evolved stars, where we take the mass-loss rate as a proxy for the initial stellar mass or current stellar age. This is consistent with the different abundance ratios found in presolar grains. We found that older objects (up to possibly 10 Gyr old) in our sample trace a previous, lower 29Si/30Si value of about 1. Material with this isotopic ratio is present in two subclasses of presolar grains, providing independent evidence of the lower ratio. Therefore, the 29Si/30Si ratio derived from the SiO emission of evolved stars is a useful diagnostic tool for the study of the GCE and presolar grains.
Precise Determination of Uranium Isotopes in Suez Canal Sediment  [PDF]
W. M. Abdellah
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2019, DOI: 10.4236/jasmi.2019.92004
Abstract:
The streambed sediments of the Suez Canal have been analyzed for determining the natural radionuclides and long-lived radionuclides such as uranium by gamma and alpha spectrometric techniques. The specific activities of 238U series, 232Th series and 40K (Bq/kg) were measured by gamma spectrometry based on Hyper-Pure Germanium detector (HPGe). The average specific activities of 226Ra(238U) series, 232Th series and 40K were ranged from 3.04 ± 1.10 to 14.70 ± 1.24 Bq/kg, from 1.12 ± 0.66 to 16.10 ± 1.30 and from 77 ± 4.90 to 350.50 ± 8.90 Bq/kg respectively. The concentration of 238U and 234U in the streambed sediments are ranged from 3.24 ± 0.21 to 13.34 ± 0.61 ppm and from 3.18 ± 0.02 to 13.77 ± 0.03 ppm in dry weight respectively. 234U/238U ratios of the sediments are relatively lower than unity in many locations indicating the preferential uranium leaching process. The results with the high ratios for 234U/238U were observed in the sediment collected from Port Said. This may be attributed to the sorption of uranium by sediment which has a relatively high content of organic matter. The geochemical behavior of sediment, the chemistry of uranium and the flow rates of water are considered as the most important factors controlling uranium isotopic composition of the streambed sediment. The result of radioactivity in sediment samples can be used to distinguish any future changes due to non-nuclear industries on the Suez Canal area.
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