WorldWideScience

Sample records for actinium 234

  1. Extraction of actinium with di-(2-ethylhexyl)phosphoric acid from hydrochloric and nitric acid solutions

    The extraction of actinium with HDEHP from Cl- and NO3- systems has been investigated. It was found that extraction of actinium from HCl solutions is much better than from HNO3 solutions. Stability constants of actinium complexes Ac(X-)+2 with Cl- and NO3- ligands were determined. Our results show that the actinium formed less stable complexes with Cl- than with NO3- ligands. 5 refs., 3 figs., 1 tab. (author)

  2. The sorption of polonium, actinium and protactinium onto geological materials

    This paper describes a combined experimental and modeling program of generic sorption studies to increase confidence in the performance assessment for a potential high-level radioactive waste repository in Japan. The sorption of polonium, actinium and protactinium onto geological materials has been investigated. Sorption of these radioelements onto bentonite, tuff and granodiorite from equilibrated de-ionized water was studied under reducing conditions at room temperature. In addition, the sorption of actinium and protactinium was investigated at 60 C. Thermodynamic chemical modeling was carried out to aid interpretation of the results

  3. Separation of Actinium 227 from the uranium minerals

    The purpose of this work was to separate Actinium 227, whose content is 18%, from the mineral carnotite found in Gomez Chihuahua mountain range in Mexico. The mineral before processing is is pre-concentrated and passed, first through anionic exchange resins, later the eluate obtained is passed through cationic resins. The resins were 20-50 MESH QOWEX and 100-200 MESH 50 X 8-20 in some cased 200-400 MESH AG 50W-X8, 1X8 in other cases. The eluates from the ionic exchange were electrodeposited on stainless steel polished disc cathode and platinum electrode as anode; under a current ODF 10mA for 2.5 to 5 hours and of 100mA for .5 of an hour. it was possible to identify the Actinium 227 by means of its descendents, TH-227 and RA-223, through alpha spectroscopy. Due to the radiochemical purity which the electro deposits were obtained the Actinium 227 was low and was not quantitatively determined. A large majority of the members of the natural radioactive series 3 were identified and even alpha energies reported in the literature with very low percentages of non-identified emissions were observed. We conclude that a more precise study is needed concerning ionic exchange and electrodeposit to obtain an Actinium 227 of radiochemical purity. (Author)

  4. Spectroscopic and computational investigation of actinium coordination chemistry.

    Ferrier, Maryline G; Batista, Enrique R; Berg, John M; Birnbaum, Eva R; Cross, Justin N; Engle, Jonathan W; La Pierre, Henry S; Kozimor, Stosh A; Lezama Pacheco, Juan S; Stein, Benjamin W; Stieber, S Chantal E; Wilson, Justin J

    2016-01-01

    Actinium-225 is a promising isotope for targeted-α therapy. Unfortunately, progress in developing chelators for medicinal applications has been hindered by a limited understanding of actinium chemistry. This knowledge gap is primarily associated with handling actinium, as it is highly radioactive and in short supply. Hence, Ac(III) reactivity is often inferred from the lanthanides and minor actinides (that is, Am, Cm), with limited success. Here we overcome these challenges and characterize actinium in HCl solutions using X-ray absorption spectroscopy and molecular dynamics density functional theory. The Ac-Cl and Ac-OH2O distances are measured to be 2.95(3) and 2.59(3) Å, respectively. The X-ray absorption spectroscopy comparisons between Ac(III) and Am(III) in HCl solutions indicate Ac(III) coordinates more inner-sphere Cl(1-) ligands (3.2±1.1) than Am(III) (0.8±0.3). These results imply diverse reactivity for the +3 actinides and highlight the unexpected and unique Ac(III) chemical behaviour. PMID:27531582

  5. Discovery of the actinium, thorium, protactinium, and uranium isotopes

    Fry, C; Thoennessen, M

    2012-01-01

    Currently, 31 actinium, 31 thorium, 28 protactinium, and 23 uranium 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.

  6. Production of high-purity radium-223 from legacy actinium-beryllium neutron sources.

    Soderquist, Chuck Z; McNamara, Bruce K; Fisher, Darrell R

    2012-07-01

    Radium-223 is a short-lived alpha-particle-emitting radionuclide with potential applications in cancer treatment. Research to develop new radiopharmaceuticals employing (223)Ra has been hindered by poor availability due to the small quantities of parent actinium-227 available world-wide. The purpose of this study was to develop innovative and cost-effective methods to obtain high-purity (223)Ra from (227)Ac. We obtained (227)Ac from two surplus actinium-beryllium neutron generators. We retrieved the actinium/beryllium buttons from the sources and dissolved them in a sulfuric-nitric acid solution. A crude actinium solid was recovered from the solution by coprecipitation with thorium fluoride, leaving beryllium in solution. The crude actinium was purified to provide about 40 milligrams of actinium nitrate using anion exchange in methanol-water-nitric acid solution. The purified actinium was then used to generate high-purity (223)Ra. We extracted (223)Ra using anion exchange in a methanol-water-nitric acid solution. After the radium was separated, actinium and thorium were then eluted from the column and dried for interim storage. This single-pass separation produces high purity, carrier-free (223)Ra product, and does not disturb the (227)Ac/(227)Th equilibrium. A high purity, carrier-free (227)Th was also obtained from the actinium using a similar anion exchange in nitric acid. These methods enable efficient production of (223)Ra for research and new alpha-emitter radiopharmaceutical development. PMID:22697483

  7. Radium, thorium, and actinium extraction from seawater using an improved manganese-oxide-coated fiber

    Laboratory experiments were conducted to determine the efficiency with which improved manganese-oxide-coated acrylic fibers extract radium, thorium, and actinium from seawater. Tests were made using surface seawater spiked with 227Ac, 227Th and 223Ra. For sample volumes of approximately 30 liters and flow rates up to 0.5 liters per minute, radium and actinium are removed quantitatively. Approximately 80-95% of the thorium is removed under these same conditions. (Auth.)

  8. Comment: 234 [Taxonomy Icon

    Full Text Available Dictyostelium discoideum Dictyostelium discoideum Dictyostelium_discoideum_L.png 234.png Hideko ... of Tsukuba) licensed under CC Attribution2.1 Japan 写真 提供:漆原秀子 (筑波大学) Photograph provided by Hid ...

  9. Production of Actinium-225 via High Energy Proton Induced Spallation of Thorium-232

    The science of cancer research is currently expanding its use of alpha particle emitting radioisotopes. Coupled with the discovery and proliferation of molecular species that seek out and attach to tumors, new therapy and diagnostics are being developed to enhance the treatment of cancer and other diseases. This latest technology is commonly referred to as Alpha Immunotherapy (AIT). Actinium-225/Bismuth-213 is a parent/daughter alpha-emitting radioisotope pair that is highly sought after because of the potential for treating numerous diseases and its ability to be chemically compatible with many known and widely used carrier molecules (such as monoclonal antibodies and proteins/peptides). Unfortunately, the worldwide supply of actinium-225 is limited to about 1,000mCi annually and most of that is currently spoken for, thus limiting the ability of this radioisotope pair to enter into research and subsequently clinical trials. The route proposed herein utilizes high energy protons to produce actinium-225 via spallation of a thorium-232 target. As part of previous R and D efforts carried out at Argonne National Laboratory recently in support of the proposed US FRIB facility, it was shown that a very effective production mechanism for actinium-225 is spallation of thorium-232 by high energy proton beams. The base-line simulation for the production rate of actinium-225 by this reaction mechanism is 8E12 atoms per second at 200 MeV proton beam energy with 50 g/cm2 thorium target and 100 kW beam power. An irradiation of one actinium-225 half-life (10 days) produces ∼100 Ci of actinium-225. For a given beam current the reaction cross section increases slightly with energy to about 400 MeV and then decreases slightly for beam energies in the several GeV regime. The object of this effort is to refine the simulations at proton beam energies of 400 MeV and above up to about 8 GeV. Once completed, the simulations will be experimentally verified using 400 MeV and 8 GeV protons

  10. Production of Actinium-225 via High Energy Proton Induced Spallation of Thorium-232

    Harvey, James T.; Nolen, Jerry; Vandergrift, George; Gomes, Itacil; Kroc, Tom; Horwitz, Phil; McAlister, Dan; Bowers, Del; Sullivan, Vivian; Greene, John

    2011-12-30

    The science of cancer research is currently expanding its use of alpha particle emitting radioisotopes. Coupled with the discovery and proliferation of molecular species that seek out and attach to tumors, new therapy and diagnostics are being developed to enhance the treatment of cancer and other diseases. This latest technology is commonly referred to as Alpha Immunotherapy (AIT). Actinium-225/Bismuth-213 is a parent/daughter alpha-emitting radioisotope pair that is highly sought after because of the potential for treating numerous diseases and its ability to be chemically compatible with many known and widely used carrier molecules (such as monoclonal antibodies and proteins/peptides). Unfortunately, the worldwide supply of actinium-225 is limited to about 1,000mCi annually and most of that is currently spoken for, thus limiting the ability of this radioisotope pair to enter into research and subsequently clinical trials. The route proposed herein utilizes high energy protons to produce actinium-225 via spallation of a thorium-232 target. As part of previous R and D efforts carried out at Argonne National Laboratory recently in support of the proposed US FRIB facility, it was shown that a very effective production mechanism for actinium-225 is spallation of thorium-232 by high energy proton beams. The base-line simulation for the production rate of actinium-225 by this reaction mechanism is 8E12 atoms per second at 200 MeV proton beam energy with 50 g/cm2 thorium target and 100 kW beam power. An irradiation of one actinium-225 half-life (10 days) produces {approx}100 Ci of actinium-225. For a given beam current the reaction cross section increases slightly with energy to about 400 MeV and then decreases slightly for beam energies in the several GeV regime. The object of this effort is to refine the simulations at proton beam energies of 400 MeV and above up to about 8 GeV. Once completed, the simulations will be experimentally verified using 400 MeV and 8 Ge

  11. Neutron-Induced Fission of Actinium-227, Protactinium-231 and Neptunium-237: Mass Distribution

    Results of radiochemical studies on the mass distribution in the neutron-induced fission of actinium-227, protactinium-231 and neptunium-237 have been presented. This work has been carried out as part of a programme to determine the mass distribution in the fission of heavy elements as a function of Z and A. All irradiations have been carried out in the core of the swimming-pool type reactor APSARA with cadmium shielding wherever necessary. Relative yields of several fission product nuclides have been obtained by a method involving a comparison of the fission product activities from the respective targets with those formed from uranium-235 simultaneously irradiated. Thermal-neutron fission yields of uranium-235 have been assumed. These results indicate a predominantly asymmetric mass distribution in all the three cases, and also a distinct though small symmetric peak in the case of actinium-227. (author)

  12. A new method for the determination of low-level actinium-227 in geological samples

    We developed a new method for the determination of 227Ac in geological samples. The method uses extraction chromatographic techniques and alpha-spectrometry and is applicable for a range of natural matrices. Here we report on the procedure and results of the analysis of water (fresh and seawater) and rock samples. Water samples were acidified and rock samples underwent total dissolution via acid leaching. A DGA (N,N,N',N'-tetra-n-octyldiglycolamide) extraction chromatographic column was used for the separation of actinium. The actinium fraction was prepared for alpha spectrometric measurement via cerium fluoride micro-precipitation. Recoveries of actinium in water samples were 80 ± 8 % (number of analyses n = 14) and in rock samples 70 ± 12 % (n = 30). The minimum detectable activities (MDA) were 0.017-0.5 Bq kg-1 for both matrices. Rock sample 227Ac activities ranged from 0.17 to 8.3 Bq kg-1 and water sample activities ranged from below MDA values to 14 Bq kg-1of 227Ac. From the analysis of several standard rock and water samples with the method we found very good agreement between our results and certified values. (author)

  13. 49 CFR 234.259 - Warning time.

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Warning time. 234.259 Section 234.259..., Inspection, and Testing Inspections and Tests § 234.259 Warning time. Each crossing warning system shall be tested for the prescribed warning time at least once every 12 months and when the warning system...

  14. 32 CFR 234.16 - Gambling.

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false Gambling. 234.16 Section 234.16 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS CONDUCT ON THE PENTAGON RESERVATION § 234.16 Gambling. Gambling in any form, or the operation of gambling devices,...

  15. 49 CFR 234.223 - Gate arm.

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Gate arm. 234.223 Section 234.223 Transportation... Maintenance Standards § 234.223 Gate arm. Each gate arm, when in the downward position, shall extend across... clearly viewed by approaching highway users. Each gate arm shall start its downward motion not less...

  16. 49 CFR 234.233 - Rail joints.

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Rail joints. 234.233 Section 234.233..., DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS Maintenance, Inspection, and Testing Maintenance Standards § 234.233 Rail joints. Each non-insulated rail joint...

  17. 49 CFR 234.251 - Standby power.

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Standby power. 234.251 Section 234.251 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., Inspection, and Testing Inspections and Tests § 234.251 Standby power. Standby power shall be tested at...

  18. 7 CFR 916.234 - Assessment rate.

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Assessment rate. 916.234 Section 916.234 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Assessment Rates § 916.234 Assessment rate. On and after March 1, 2009, an assessment rate of $0.0175 per...

  19. 49 CFR 234.229 - Shunting sensitivity.

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., Inspection, and Testing Maintenance Standards § 234.229 Shunting sensitivity. Each highway-rail...

  20. Analysis of the gamma spectra of the uranium, actinium, and thorium decay series

    Momeni, M.H.

    1981-09-01

    This report describes the identification of radionuclides in the uranium, actinium, and thorium series by analysis of gamma spectra in the energy range of 40 to 1400 keV. Energies and absolute efficiencies for each gamma line were measured by means of a high-resolution germanium detector and compared with those in the literature. A gamma spectroscopy method, which utilizes an on-line computer for deconvolution of spectra, search and identification of each line, and estimation of activity for each radionuclide, was used to analyze soil and uranium tailings, and ore.

  1. Analysis of the gamma spectra of the uranium, actinium, and thorium decay series

    This report describes the identification of radionuclides in the uranium, actinium, and thorium series by analysis of gamma spectra in the energy range of 40 to 1400 keV. Energies and absolute efficiencies for each gamma line were measured by means of a high-resolution germanium detector and compared with those in the literature. A gamma spectroscopy method, which utilizes an on-line computer for deconvolution of spectra, search and identification of each line, and estimation of activity for each radionuclide, was used to analyze soil and uranium tailings, and ore

  2. Dicty_cDB: SSH234 [Dicty_cDB

    Full Text Available SS (Link to library) SSH234 (Link to dictyBase) - - - Contig-U16581-1 SSH234E (Link... to Original site) - - - - - - SSH234E 564 Show SSH234 Library SS (Link to library) Clone ID SSH234 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/SS/SSH2-B/SSH234Q.Seq.d/ Representative seq. ID SSH23...4E (Link to Original site) Representative DNA sequence >SSH234 (SSH234Q) /CSM/SS/SSH2-B/SSH234Q.Seq.d/ CAATT...3 Translated Amino Acid sequence n*lkkkkknxkki**vlkwysfnkkkkkxtiisskkkikxkkkkxkkk***aipwdleki kkfkkkiknnkk*k

  3. 48 CFR 234.004 - Acquisition strategy.

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Acquisition strategy. 234..., DEPARTMENT OF DEFENSE SPECIAL CATEGORIES OF CONTRACTING MAJOR SYSTEM ACQUISITION 234.004 Acquisition strategy. (1) See 209.570 for policy applicable to acquisition strategies that consider the use of lead...

  4. In-source laser spectroscopy developments at TRILIS—towards spectroscopy on actinium and scandium

    Resonance Ionization Laser Ion Sources (RILIS) have become a versatile tool for production and study of exotic nuclides at Isotope Separator On-Line (ISOL) facilities such as ISAC at TRIUMF. The recent development and addition of a grating tuned spectroscopy laser to the TRIUMF RILIS solid state laser system allows for wide range spectral scans to investigate atomic structures on short lived isotopes, e.g., those from the element actinium, produced in uranium targets at ISAC. In addition, development of new and improved laser ionization schemes for rare isotope production at ISAC is ongoing. Here spectroscopic studies on bound states, Rydberg states and autoionizing (AI) resonances on scandium using the existing off-line capabilities are reported. These results allowed to identify a suitable ionization scheme for scandium via excitation into an autoionizing state at 58,104 cm − 1 which has subsequently been used for ionization of on-line produced exotic scandium isotopes.

  5. 8 CFR 234.2 - Landing requirements.

    2010-01-01

    ... permission from an immigration officer. (d) Emergency or forced landing. Should any aircraft carrying... emergency or forced landing. ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Landing requirements. 234.2 Section...

  6. 24 CFR 234.501 - Eligibility requirements.

    2010-04-01

    ... CONDOMINIUM OWNERSHIP MORTGAGE INSURANCE Eligibility Requirements-Projects-Conversion Individual Sales Units § 234.501 Eligibility requirements. The requirements set forth in 24 CFR part 200, subpart A, apply...

  7. 14 CFR 234.3 - Applicability.

    2010-01-01

    ... Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS AIRLINE SERVICE QUALITY PERFORMANCE REPORTS § 234.3 Applicability. This part applies to certain... voluntary reporting to on-time performance by carriers....

  8. Remeasurement of (234)U Half-Life.

    Varga, Zsolt; Nicholl, Adrian; Wallenius, Maria; Mayer, Klaus

    2016-03-01

    The half-life of (234)U has been measured using a novel approach. In this method, a uranium material was chemically purified from its thorium decay product at a well-known time. The ingrowth of the (230)Th daughter product in the material was followed by measuring the accumulated (230)Th daughter product relative to its parent (234)U nuclide using inductively coupled plasma mass spectrometry. Then, the (234)U decay constant and the respective half-life could be calculated using the radioactive decay equations based on the n((230)Th)/n((234)U) amount ratio. The obtained (234)U half-life is 244 900 ± 670 years (k = 1), which is in good agreement with the previously reported results in the literature with comparable uncertainty. The main advantages of the proposed method are that it does not require the assumption of secular equilibrium between (234)U and (238)U. Moreover, the calculation is independent from the (238)U half-life value and its uncertainty. The suggested methodology can also be applied for the remeasurement of the half-lives of several other long-lived radionuclides. PMID:26823129

  9. Dicty_cDB: SSI234 [Dicty_cDB

    Full Text Available SS (Link to library) SSI234 (Link to dictyBase) - - - Contig-U14087-1 SSI234E (Link... to Original site) - - - - - - SSI234E 708 Show SSI234 Library SS (Link to library) Clone ID SSI234 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/SS/SSI2-B/SSI234Q.Seq.d/ Representative seq. ID SSI23...4E (Link to Original site) Representative DNA sequence >SSI234 (SSI234Q) /CSM/SS/SSI2-B/SSI234Q.Seq.d/ GACCC...iiikkkkk Frame B: tqtnldilsstwkssitkmfiripw*ri*f*rg*nyi**fkktiiv*ttttlsrrrfqnr snscnn*lhfret*fsw*nqrrksksssm

  10. Developments towards in-gas-jet laser spectroscopy studies of actinium isotopes at LISOL

    Raeder, S.; Bastin, B.; Block, M.; Creemers, P.; Delahaye, P.; Ferrer, R.; Fléchard, X.; Franchoo, S.; Ghys, L.; Gaffney, L. P.; Granados, C.; Heinke, R.; Hijazi, L.; Huyse, M.; Kron, T.; Kudryavtsev, Yu.; Laatiaoui, M.; Lecesne, N.; Luton, F.; Moore, I. D.; Martinez, Y.; Mogilevskiy, E.; Naubereit, P.; Piot, J.; Rothe, S.; Savajols, H.; Sels, S.; Sonnenschein, V.; Traykov, E.; Van Beveren, C.; Van den Bergh, P.; Van Duppen, P.; Wendt, K.; Zadvornaya, A.

    2016-06-01

    To study exotic nuclides at the borders of stability with laser ionization and spectroscopy techniques, highest efficiencies in combination with a high spectral resolution are required. These usually opposing requirements are reconciled by applying the in-gas-laser ionization and spectroscopy (IGLIS) technique in the supersonic gas jet produced by a de Laval nozzle installed at the exit of the stopping gas cell. Carrying out laser ionization in the low-temperature and low density supersonic gas jet eliminates pressure broadening, which will significantly improve the spectral resolution. This article presents the required modifications at the Leuven Isotope Separator On-Line (LISOL) facility that are needed for the first on-line studies of in-gas-jet laser spectroscopy. Different geometries for the gas outlet and extraction ion guides have been tested for their performance regarding the acceptance of laser ionized species as well as for their differential pumping capacities. The specifications and performance of the temporarily installed high repetition rate laser system, including a narrow bandwidth injection-locked Ti:sapphire laser, are discussed and first preliminary results on neutron-deficient actinium isotopes are presented indicating the high capability of this novel technique.

  11. Neutron induced fission of 234U

    Pomp S.; Al-Adili A.; Oberstedt S.; Hambsch F.-J.

    2012-01-01

    The fission fragment properties of 234U(n,f) were investigated as a function of incident neutron energy from 0.2 MeV up to 5 MeV. The fission fragment mass, angular distribution and kinetic energy were measured with a double Frisch-grid ionization chamber using both analogue and digital data acquisition techniques. The reaction 234U(n,f) is relevant, since it involves the same compound nucleus as formed after neutron evaporation from highly excited 236U*, the so-called second-chance fission o...

  12. 49 CFR 234.245 - Signs.

    2010-10-01

    ... TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS Maintenance, Inspection, and Testing Maintenance Standards § 234.245 Signs. Each sign mounted on a highway-rail grade crossing signal post shall be maintained in good condition and be visible to the highway user. Inspections and Tests...

  13. 49 CFR 234.3 - Application.

    2010-10-01

    ... TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS General § 234.3 Application. With the... if one or more of the following exists on its line: (1) A public highway-rail crossing that is in use; (2) An at-grade rail crossing that is in use; (3) A bridge over a public road or waters used...

  14. 49 CFR 234.1 - Scope.

    2010-10-01

    ... TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS General § 234.1 Scope. This part imposes minimum maintenance, inspection, and testing standards for highway-rail grade crossing warning... particular identified States to develop State highway-rail grade crossing action plans. This part does...

  15. 49 CFR 234.213 - Grounds.

    2010-10-01

    ... TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS Maintenance, Inspection, and Testing Maintenance Standards § 234.213 Grounds. Each circuit that affects the proper functioning of a highway-rail... in the circuit. This requirement does not apply to: circuits that include track rail;...

  16. Dicty_cDB: CFJ234 [Dicty_cDB

    Full Text Available CF (Link to library) CFJ234 (Link to dictyBase) - - - Contig-U16517-1 CFJ234P (Link to Original ... *edmqvqv*ekviy*el kiffhlqevllnvvykvfqifilninhyymif*ivf *rtn*kkplihtyqqlnqerdhkm *lylwlvvslmkrh*pftllil*ilv ...

  17. 17 CFR 256.234 - Accounts payable to associate companies.

    2010-04-01

    ... companies. 256.234 Section 256.234 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) UNIFORM SYSTEM OF ACCOUNTS FOR MUTUAL SERVICE COMPANIES AND SUBSIDIARY SERVICE COMPANIES, PUBLIC UTILITY HOLDING COMPANY ACT OF 1935 7. Current and Accrued Liabilities § 256.234 Accounts payable...

  18. 24 CFR 234.65 - Nature of title.

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Nature of title. 234.65 Section 234.65 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued... OWNERSHIP MORTGAGE INSURANCE Eligibility Requirements-Individually Owned Units § 234.65 Nature of title....

  19. 32 CFR 234.12 - Restriction on animals.

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false Restriction on animals. 234.12 Section 234.12 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS CONDUCT ON THE PENTAGON RESERVATION § 234.12 Restriction on animals. Animals, except guide...

  20. 34 CFR 75.234 - The conditions of the grant.

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false The conditions of the grant. 75.234 Section 75.234 Education Office of the Secretary, Department of Education DIRECT GRANT PROGRAMS How Grants Are Made Procedures to Make A Grant § 75.234 The conditions of the grant. (a) The Secretary makes a grant to...

  1. 22 CFR 23.4 - Representative value in exchange.

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Representative value in exchange. 23.4 Section 23.4 Foreign Relations DEPARTMENT OF STATE FEES AND FUNDS FINANCE AND ACCOUNTING § 23.4 Representative value in exchange. Representative value in exchange for the collection of a fee means...

  2. 49 CFR 234.255 - Gate arm and gate mechanism.

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Gate arm and gate mechanism. 234.255 Section 234... Maintenance, Inspection, and Testing Inspections and Tests § 234.255 Gate arm and gate mechanism. (a) Each gate arm and gate mechanism shall be inspected at least once each month. (b) Gate arm movement shall...

  3. 50 CFR 648.234 - Gear restrictions. [Reserved

    2010-10-01

    ... Fishery § 648.234 Gear restrictions. ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Gear restrictions. 648.234 Section 648.234 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC...

  4. 49 CFR 234.235 - Insulated rail joints.

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Insulated rail joints. 234.235 Section 234.235..., DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS Maintenance, Inspection, and Testing Maintenance Standards § 234.235 Insulated rail joints. Each insulated rail joint...

  5. 24 CFR 234.270 - Condition of the multifamily structure.

    2010-04-01

    ... structure. 234.270 Section 234.270 Housing and Urban Development Regulations Relating to Housing and Urban... § 234.270 Condition of the multifamily structure. (a) When a family unit is conveyed or a mortgage is... principal rating organization doing business in the state. If the property is located in a state which...

  6. 12 CFR 23.4 - Investment in personal property.

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Investment in personal property. 23.4 Section 23.4 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY LEASING General Provisions § 23.4 Investment in personal property. (a) General rule. A national bank may acquire specific property to be leased only after the bank...

  7. Colloidal 234Th and the turnover of oceanic DOC

    234Th has been proposed to be a tracer for the labile, colloidal fraction of DOC in seawater. During the recent North Atlantic Bloom Experiment (NABE) the turnover of DOC was directly measured. 234Th and total suspended matter (Cp) were also measured by different research groups. Using the NABE 234Th data the authors have calculated the turnover rate of colloidal material using the Brownian Pumping model of Honeyman and Santschi and the 4-box particle cycling model of Moran and Buesseler. The rate constants for colloid cycling determined from the 234Th data agree well with the experimentally determined rate constants for turnover of DOC

  8. An Empirical Method for Determining 234U Percentage

    When isotopic information for uranium is provided, the concentration of 234U is frequently neglected. Often the isotopic content is given as a percentage of 235U with the assumption that the remainder consists of 238U. In certain applications, such as heat output, the concentration of 234U can be a significant contributing factor. For situations where only the 235U and 238U values are given, a simple way to calculate the 234U component would be beneficial. The approach taken here is empirical. A series of uranium standards with varying enrichments were analyzed. The 234U and 235U data were fit using a second order polynomial.

  9. Neutron induced fission of 234U

    Hambsch, F.-J.; Al-Adili, A.; Oberstedt, S.; Pomp, S.

    2012-02-01

    The fission fragment properties of 234U(n,f) were investigated as a function of incident neutron energy from 0.2 MeV up to 5 MeV. The fission fragment mass, angular distribution and kinetic energy were measured with a double Frisch-grid ionization chamber using both analogue and digital data acquisition techniques. The reaction 234U(n,f) is relevant, since it involves the same compound nucleus as formed after neutron evaporation from highly excited 236U*, the so-called second-chance fission of 235U. Experimental data on fission fragment properties like fission fragment mass and total kinetic energy (TKE) as a function of incident neutron energy are rather scarce for this reaction. For the theoretical modelling of the reaction cross sections for Uranium isotopes this information is a crucial input parameter. In addition, 234U is also an important isotope in the Thorium-based fuel cycle. The strong anisotropy of the angular distribution around the vibrational resonance at En = 0.77 MeV could be confirmed using the full angular range. Fluctuations in the fragment TKE have been observed in the threshold region around the strong vibrational resonance at En = 0.77 MeV. The present results are in contradiction with corresponding literature values. Changes in the mass yield around the vibrational resonance and at En = 5 MeV relative to En = 2 MeV show a different signature. The drop in mean TKE around 2.5 to 3 MeV points to pair breaking as also observed in 235,238U(n,f). The measured two-dimensional mass yield and TKE distribution have been described in terms of fission modes. The yield of the standard 1 (S1) mode shows fluctuations in the threshold of the fission cross section due to the influence of the resonance and levels off at about 20% yield for higher incident neutron energies. The S2 mode shows the respective opposite behaviour. The mean TKE of both modes decreases with En. The decrease in mean TKE overrules the increase in S1 yield, so the mean TKE is dropping

  10. Neutron induced fission of 234U

    Pomp S.

    2012-02-01

    Full Text Available The fission fragment properties of 234U(n,f were investigated as a function of incident neutron energy from 0.2 MeV up to 5 MeV. The fission fragment mass, angular distribution and kinetic energy were measured with a double Frisch-grid ionization chamber using both analogue and digital data acquisition techniques. The reaction 234U(n,f is relevant, since it involves the same compound nucleus as formed after neutron evaporation from highly excited 236U*, the so-called second-chance fission of 235U. Experimental data on fission fragment properties like fission fragment mass and total kinetic energy (TKE as a function of incident neutron energy are rather scarce for this reaction. For the theoretical modelling of the reaction cross sections for Uranium isotopes this information is a crucial input parameter. In addition, 234U is also an important isotope in the Thorium-based fuel cycle. The strong anisotropy of the angular distribution around the vibrational resonance at En = 0.77 MeV could be confirmed using the full angular range. Fluctuations in the fragment TKE have been observed in the threshold region around the strong vibrational resonance at En = 0.77 MeV. The present results are in contradiction with corresponding literature values. Changes in the mass yield around the vibrational resonance and at En = 5 MeV relative to En = 2 MeV show a different signature. The drop in mean TKE around 2.5 to 3 MeV points to pair breaking as also observed in 235,238U(n,f. The measured two-dimensional mass yield and TKE distribution have been described in terms of fission modes. The yield of the standard 1 (S1 mode shows fluctuations in the threshold of the fission cross section due to the influence of the resonance and levels off at about 20% yield for higher incident neutron energies. The S2 mode shows the respective opposite behaviour. The mean TKE of both modes decreases with En. The decrease in mean TKE overrules the increase in S1 yield, so the mean

  11. 27 CFR 46.234 - Tax payment deadline.

    2010-04-01

    ... Public Law 111-3 specifies a tax payment deadline of August 1, 2009. However, section 5703(b)(2)(E) of... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Tax payment deadline. 46.234 Section 46.234 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE...

  12. Dicty_cDB: VSH234 [Dicty_cDB

    Full Text Available VS (Link to library) VSH234 (Link to dictyBase) - G21453 DDB0220111 Contig-U06849-1 VSH234P (Lin ... eve... 48 0.37 1 ( EC313530 ) REPROTRACTF081141F16 POSSUM _01-POSSUM -C-REPROTRAC... 48 0.37 1 dna update 2009 ...

  13. 37 CFR 2.34 - Bases for filing.

    2010-07-01

    ... applicant must either: (A) Specify the filing date, serial number and country of the first regularly filed... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Bases for filing. 2.34 Section 2.34 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT...

  14. 15 CFR 23.4 - Cost and percentage estimates.

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Cost and percentage estimates. 23.4... LOCATION AND RECOVERY OF MISSING CHILDREN § 23.4 Cost and percentage estimates. It is estimated that this... estimate that 9% of its penalty mail will transmit missing children photographs and information when...

  15. 14 CFR 234.6 - Baggage-handling statistics.

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Baggage-handling statistics. 234.6 Section 234.6 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION... statistics. Each reporting carrier shall report monthly to the Department on a domestic system...

  16. 48 CFR 252.234-7002 - Earned Value Management System.

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Earned Value Management... of Provisions And Clauses 252.234-7002 Earned Value Management System. As prescribed in 234.203(2), use the following clause: Earned Value Management System (APR 2008) (a) In the performance of...

  17. Dicty_cDB: SFC234 [Dicty_cDB

    Full Text Available SF (Link to library) SFC234 (Link to dictyBase) - - - Contig-U10050-1 SFC234Z (Link to Original ... H chr... 38 0.23 ( Q19673 ) RecName: Full=Putative tyrosinase -like protein tyr-3; F... 37 0.66 protein update 20 ...

  18. 48 CFR 252.234-7001 - Notice of Earned Value Management System.

    2010-10-01

    ... Management System. 252.234-7001 Section 252.234-7001 Federal Acquisition Regulations System DEFENSE... CLAUSES Text of Provisions And Clauses 252.234-7001 Notice of Earned Value Management System. As prescribed in 234.203(1), use the following provision: Notice of Earned Value Management System (APR 2008)...

  19. Groundwater seepage from the Ranger uranium mine tailings dam: radioisotopes of radium, thorium and actinium. Supervising Scientist report 106

    Monitoring of bores near the Ranger uranium mine tailings dam has revealed deterioration in water quality in several bores since 1983. In a group of bores to the north of the dam, increases have been observed of up to 500 times for sulphate concentrations and of up to 5 times for 226Ra concentrations. Results are presented here of measurements of members of the uranium, thorium and actinium decay series in borewater samples collected between 1985 and 1993. In particular, measurements of all four naturally-occurring radium isotopes have been used in an investigation of the mechanism of radium concentration changes. For the most seepage-affected bores the major findings of the study include: 228Ra/226Ra 223Ra /226Ra and 224Ra/228Ra ratios all increased over the course of the study; barium concentrations show high seasonal variability, being lower in November than May, but strontium concentrations show a steady increase with time. Calculations show that the groundwater is probably saturated with respect to barite but not with respect to celestite or anglesite; sulphide concentrations are low in comparison with sulphate, and are higher in November than in May; and 227Ac concentrations have increased with time, but do not account for the high 223Ra/226Ra ratios. It is concluded on the basis of these observations that increases in Ra isotope concentrations observed in a number of seepage-affected bores arise from increases in salinity leading to desorption of radium from adsorption sites in the vicinity of the bore rather by direct transport of radium from the tailings. Increased salinity is also causing the observed increases in 227Ac and strontium concentrations, while formation of a barite solid phase in the groundwater is causing the removal of some radium from solution. This is the cause of the increasing radium isotope ratios noted above

  20. 24 CFR 234.280 - Cancellation of hazard insurance.

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Cancellation of hazard insurance... § 234.280 Cancellation of hazard insurance. The provisions of § 203.382 incorporated by reference shall apply to hazard insurance policies carried solely for the family unit....

  1. 10 CFR 72.234 - Conditions of approval.

    2010-01-01

    ... Spent Fuel Storage Casks § 72.234 Conditions of approval. (a) The certificate holder and applicant for a CoC shall ensure that the design, fabrication, testing, and maintenance of a spent fuel storage cask... that the design, fabrication, testing, and maintenance of spent fuel storage casks are conducted...

  2. 48 CFR 1852.234-2 - Earned Value Management System.

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Earned Value Management... and Clauses 1852.234-2 Earned Value Management System. As prescribed in 1834.203-70(b) insert the following clause: Earned Value Management System (NOV 2006) (a) In the performance of this contract,...

  3. 14 CFR 234.11 - Disclosure to consumers.

    2010-01-01

    ...) ECONOMIC REGULATIONS AIRLINE SERVICE QUALITY PERFORMANCE REPORTS § 234.11 Disclosure to consumers. Link to... public, the carrier shall disclose upon reasonable request the on-time performance code for any flight... public, the carrier shall disclose upon reasonable request the on-time performance code for any...

  4. 48 CFR 52.234-2 - Notice of Earned Value Management System-Pre-Award IBR.

    2010-10-01

    ... Management System-Pre-Award IBR. 52.234-2 Section 52.234-2 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.234-2 Notice of Earned Value Management System—Pre-Award IBR. As prescribed in 34.203(a) use the following provision: Notice of Earned Value Management System—Pre-Award IBR (JUL...

  5. 48 CFR 52.234-3 - Notice of Earned Value Management System-Post Award IBR.

    2010-10-01

    ... Management System-Post Award IBR. 52.234-3 Section 52.234-3 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.234-3 Notice of Earned Value Management System—Post Award IBR. As prescribed in 34.203(b) use the following provision: Notice of Earned Value Management System—Post Award IBR (JUL...

  6. 8 CFR 234.4 - International airports for entry of aliens.

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false International airports for entry of aliens. 234.4 Section 234.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS DESIGNATION OF PORTS OF ENTRY FOR ALIENS ARRIVING BY CIVIL AIRCRAFT § 234.4 International airports for...

  7. 48 CFR 1852.234-1 - Notice of Earned Value Management System.

    2010-10-01

    ... Management System. 1852.234-1 Section 1852.234-1 Federal Acquisition Regulations System NATIONAL AERONAUTICS... Provisions and Clauses 1852.234-1 Notice of Earned Value Management System. As prescribed in 1834.203-70(a), insert the following provision: Notice of Earned Value Management System (NOV 2006) (a) The offeror...

  8. 48 CFR 352.234-3 - Full earned value management system.

    2010-10-01

    ... management system. 352.234-3 Section 352.234-3 Federal Acquisition Regulations System HEALTH AND HUMAN....234-3 Full earned value management system. As prescribed in 334.203-70(c), the Contracting Officer shall insert the following clause: Full Earned Value Management System (October 2008) (a) The...

  9. 48 CFR 352.234-4 - Partial earned value management system.

    2010-10-01

    ... management system. 352.234-4 Section 352.234-4 Federal Acquisition Regulations System HEALTH AND HUMAN....234-4 Partial earned value management system. As prescribed in 334.203-70(d), the Contracting Officer shall insert the following clause: Partial Earned Value Management System (October 2008) (a)...

  10. 20 CFR 234.12 - 1937 Act lump-sum death payment.

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false 1937 Act lump-sum death payment. 234.12 Section 234.12 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD RETIREMENT ACT LUMP-SUM PAYMENTS Lump-Sum Death Payment § 234.12 1937 Act lump-sum death payment. (a) The 1937...

  11. Recovery and purification of uranium-234 from aged plutonium-238

    The current production methods used to recover and purify uranium-234 from aged plutonium-238 at Mound Laboratory are presented. The three chemical separation steps are described in detail. In the initial separation step, the bulk of the plutonium is precipitated as the oxalate. Successively lower levels of plutonium are achieved by anion exchange in nitrate media and by anion exchange in chloride media. The procedures used to characterize and analyze the final U3O8 are given

  12. distributions for the thermal neutron induced fission of 234U

    Al-Adili A.

    2016-01-01

    In addition, the analysis of thermal neutron induced fission of 234U(n,f will be discussed. Currently analysis of data is ongoing, originally taken at the ILL reactor. The experiment is of particular interest since no measurement exist of the mass and energy distributions for this system at thermal energies. One main problem encountered during analysis was the huge background of 235U(nth,f. Despite the negligible isotopic traces in the sample, the cross section difference is enormous. Solution to this parasitic background will be highlighted.

  13. Investigations on the biological behaviour and the decorporation of 234Th in the rat

    In this work the biological behaviour of 234Th in the rat has been studied as function of mass, chemical form and route of entry. Further it was investigated if there is a correlation between iron metabolism and distribution of 234Th in the organism. The mobilization of 234Th with Ca- und Zn-DTPA as well as with other chelators and their combinations with DTPA has been determined as basis for acceptable therapeutic procedures for decorporation. (orig.)

  14. 20 CFR 234.11 - 1974 Act lump-sum death payment.

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false 1974 Act lump-sum death payment. 234.11... LUMP-SUM PAYMENTS Lump-Sum Death Payment § 234.11 1974 Act lump-sum death payment. (a) The total amount... household” as the employee at the time of the employee's death. (Refer to § 234.21 for an explanation...

  15. 234U/238U signatures associated with uranium ore bodies: part 3 Koongarra

    The Koongarra ore body is an early Proterozoic U ore body in the Alligator Rivers U province, Northern Territory, Australia. It has surface expression with a redox front located ∼30 m below the surface. The 234U/238U activity ratios (AR) for the ground water and the amorphous phase of the solid have been analysed for the ore zone and dispersion halo as a function of depth. The results display a 234U/238U AR signature with depth which may be common to all U ore bodies. The 234U/238U AR is depressed below secular equilibrium in the weathered material above the redox front; rises significantly above secular equilibrium in the vicinity of the redox front; and is followed by a gradual decrease with depth below the redox front. The amplitude of the profile is a function of local conditions. A model is proposed for the signature in which oxidising waters preferentially leach the 234U sites at the redox front due to preconditioning of the 234U sites by α recoil during the decay of 238U to 234U. Mass balance requires the solid material left behind the redox front to have a 234U/238U AR reduced below 1. Local second order effects may be superimposed on the signature. The signature may have application to calibrating scenarios for nuclear waste repositories, assisting in understanding historical climates, economic evaluation of U ore bodies and U exploration. -- Highlights: ► The 234U/238U AR data of the Koongaara U deposit was re-examined. ► The 234U/238U AR was depressed below 1 above the redox front. ► The 234U/238U AR was elevated above 1 at the redox front. ► The 234U/238U AR was decreased beyond the redox front. ► The data indicates that U ore bodies have a generic 234U/238U AR signature

  16. Preparation and characterisation of 234U tracer for mass spectrometry and alpha spectrometry

    234U was milked from 15 years aged 238Pu prepared earlier by neutron irradiation of 237Np. Ion exchange procedure using Dowex 1 X 8 resin in the nitric acid medium was followed for this purpose, in a glove box. The purified 234U was characterised by alpha spectrometry and thermal ionisation mass spectrometry for its 238Pu content and the isotopic composition of uranium, respectively. Alpha activity ratio of 234U/238Pu was 0.015 and the abundance of 234U was about 99 atom percent. (author). 1 fig

  17. Neutron Capture Cross Sections of 236U and 234U

    Accurate neutron capture cross sections of the actinide elements at neutron energies up to 1 MeV are needed to better interpret archived nuclear test data, for post-detonation nuclear attribution, and the Advanced Fuel Cycle Initiative. The Detector for Advance Neutron Capture Experiments, DANCE, has unique capabilities that allow the differentiation of capture gamma rays from fission gamma rays and background gamma rays from scattered neutrons captured by barium isotopes in the barium fluoride scintillators. The DANCE array has a high granularity, 160 scintillators, high efficiency, and nearly 4-π solid angle. Through the use of cuts in cluster multiplicity and calorimetric energy the capture gamma-rays are differentiated from other sources of gamma rays. The preliminary results for the capture cross sections of 236U are in agreement with the ENDF/B-VI evaluation. The preliminary results for 234U lower are than ENDF/B-VI evaluation and are closer to older evaluations

  18. New $ubvri$ photometry of 234 M33 star clusters

    Ma, Jun

    2013-01-01

    This is the second paper of our series. In this paper, we present $UBVRI$ photometry for 234 star clusters in the field of M33. For most of these star clusters, there is photometry in only two bands in previous studies. The photometry of these star clusters is performed using archival images from the Local Group Galaxies Survey, which covers 0.8 deg$^2$ along the major axis of M33. Detailed comparisons show that, in general, our photometry is consistent with previous measurements, especially, our photometry is in good agreement with Zloczewski & Kaluzny. Combined with the star clusters' photometry in previous studies, we present some results: none of the M33 youngest clusters ($\\sim 10^7$ yr) have masses approaching $10^5$ $M_{\\odot}$; comparisons with models of simple stellar populations suggest a large range of ages of M33 star clusters, and some as old as the Galactic globular clusters.

  19. 45 CFR 234.11 - Assistance in the form of money payments.

    2010-10-01

    ... 45 Public Welfare 2 2010-10-01 2010-10-01 false Assistance in the form of money payments. 234.11... FINANCIAL ASSISTANCE TO INDIVIDUALS § 234.11 Assistance in the form of money payments. (a) Federal financial participation is available in money payments made under a State plan under title I, IV-A, X, XIV, or XVI of...

  20. 49 CFR 234.237 - Reverse switch cut-out circuit.

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Reverse switch cut-out circuit. 234.237 Section... Maintenance, Inspection, and Testing Maintenance Standards § 234.237 Reverse switch cut-out circuit. A switch, when equipped with a switch circuit controller connected to the point and interconnected with...

  1. 49 CFR 234.241 - Protection of insulated wire; splice in underground wire.

    2010-10-01

    ... underground wire. 234.241 Section 234.241 Transportation Other Regulations Relating to Transportation... of insulated wire; splice in underground wire. Insulated wire shall be protected from mechanical injury. The insulation shall not be punctured for test purposes. A splice in underground wire shall...

  2. 49 CFR 234.219 - Gate arm lights and light cable.

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Gate arm lights and light cable. 234.219 Section... Maintenance, Inspection, and Testing Maintenance Standards § 234.219 Gate arm lights and light cable. Each gate arm light shall be maintained in such condition to be properly visible to approaching...

  3. 14 CFR 234.4 - Reporting of on-time performance.

    2010-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS AIRLINE SERVICE QUALITY PERFORMANCE REPORTS § 234.4 Reporting of on-time performance. (a) Each reporting carrier shall file BTS Form 234 “On-Time Flight Performance Report” with the... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Reporting of on-time performance....

  4. Direct alpha-recoil as a process to generate U-234/U-238 disequilibrium in groundwater

    We discuss quantitatively the capability of direct α-recoil to create observable radioactive disequilibrium (U-234/U-238 activity ratio > 1) in flowing groundwater. Coupled equations for radioactive decay chain are formulated for the solid U source and for the corresponding groundwater receiving the recoiling U-234 atoms. U-rich fracture coating material and the water flowing in the fracture are discussed in detail. The novel modelling approach worked well and provides a useful tool for more detailed site-specific studies with more detailed input data. The approach appears feasible because the equations are based on straightforward mass balance considerations. α-recoil -induced enrichment of U-234 in groundwater is a slow process: the increase of U-234/U-238 activity ration to notable values above unity will take hundreds to thousands of years. Strong groundwater flow prevents any local recoil-induced U-234 enrichment in the water. (author)

  5. Preparation and characterization of 234U for mass spectrometry and alpha-spectrometry

    234U of high isotopic purity (>99 atom%) as well as of high radiochemical purity was separated from aged 238Pu prepared by neutron irradiation of 237Np. Methodologies based on ion exchange and solvent extraction procedures were used to achieve high decontamination factor from 238Pu owing to the very high α-specific activity of 238Pu (2800 times) in comparison to that of 234U. Isotopic composition of purified 234U was determined by thermal ionisation mass spectrometry. Alpha spectrometry was used for checking the radiochemical purity of 234U with respect to concomitant α-emitting nuclides. The separated 234U will be useful for different investigations using mass spectrometry and alpha spectrometry. (author)

  6. 234U/238U signatures associated with uranium ore bodies: part 2 Manyingee

    The Manyingee ore body is a roll-front U ore body located at depth in the Cretaceous sandstone sediments of a Proterozoic palaeo valley. It is located in a confined aquifer. The aquifer is recharged 4 km upstream by the Ashburton River. Groundwater samples were collected at and up to 4.7 km downstream of the ore body. The ground water 234U/238U activity ratios (AR) were elevated to 1.86 in the vicinity of the ore body and then declined to 1.06 over the 4.7 km transect. The elevated 234U/238U ARs are attributed to selective leaching of 234U sites by oxidising waters, with α recoil as a necessary precursor to produce activated 234U sites. Direct ejection into another phase following α recoil is considered to be a minor contributor to 234U –238U disequilibrium in this environment. The profile is considered to be typical of the 234U/238U AR profile at and down gradient of the redox front of a U ore body. -- Highlights: ► The 234U/238U AR of the ground water of a roll-front U deposit was determined. ► The ground water was sampled at and beyond the redox front. ► The 234U/238U AR was elevated to 1.8 at the redox front. ► The 234U/238U AR was decreased down gradient of the redox front. ► A generic 234U/238U AR signature is proposed for U ore bodies

  7. Transport of 234U in the Opalinus Clay on centimetre to decimetre scales

    The Opalinus Clay formation in North Switzerland is a potential host rock for a deep underground radioactive waste repository. The distribution of 238U, 234U and 230Th was studied in rock samples of the Opalinus Clay from an exploratory borehole at Benken (Canton of Zurich) using MC-ICP-MS. The aim was to assess the in situ, long-term migration behaviour of 234U in this rock. Very low hydraulic conductivities of the Opalinus Clay, reducing potential of the pore water and its chemical equilibrium with the host rock are expected to render both 238U and 230Th immobile. If U is heterogeneously distributed in the Opalinus Clay, gradients in the supply of 234U from the rock matrix to the pore water by the decay of 238U will be established. Diffusive redistribution separates 234U from its immobile parent 238U resulting in bulk rock 234U/238U activity disequilibria. These may provide a means of estimating the mobility of 234U in the rock if the diffusion rate of 234U is significant compared to its decay rate. Sampling was carried out on two scales. Drilling of cm-spaced samples from the drill-core was done to study mobility over short distances and elucidate possible small-scale lithological control. Homogenized 25-cm-long portions of a 2-m-long drill-core section were prepared to provide information on transport over a longer distance. Variations in U and/or Th content on the cm-scale between clays and carbonate-sandy layers are revealed by β-scanning, which shows that the (dominant) clay is richer in both elements. Samples were digested using aqua regia followed by total HF dissolution, yielding two fractions. In all studied samples U was found to be concentrated in the HF digestion fraction. It has a high U/Th ratio and a study by SEM-EDS points to sub-μm up to several μm in size zircon grains as the main U-rich phase. This fraction consistently has 234U/238U activity ratios below unity. The minute zircon grains constitute the major reservoir of U in the rock and act

  8. Analysis of common cause failure in Wolsong 2/3/4 NPPs PSA

    Wolsong 2/3/4 Nuclear Power Plants (WS 2/3/4 NPPs) are CANDU 6 type Pressurized Heavy Water Reactors (PHWRs) being built in Wolsong site of Korea by Korea Power Electric Corporation (KEPCO). WS 2/3/4 NPPs are designed by Atomic Energy of Canada Ltd. (AECL). AECL performs Probabilistic Safety Assessment (PSA) for these NPPs. In this PSA, however, the effect of Common Cause Failure (CCF) is not analyzed due to the limitation of CANDU reliability data. Since the CCF is regarded as one of the most dominant contributors to the total core damage frequency (CDF) in Pressurized Water Reactor (PWR) PSA. KEPCO and Korea Atomic Energy Research Institute (KAERI) initiated WS 2/3/4 NPPs Level 2 PSA which includes the CCF analysis and detailed HRA. In WS 2/3/4 NPPs Level 2 PSA, the authors reviewed the CCF data used in PWR PSA, and applied these data for WS 2/3/4 NPPs Level 2 PSA. The MGL method is implemented for the CCF analysis of WS 2/3/4 NPPs. The analyzed results show that the effect of CCF is not negligible in CANDU PSA as well as in PWR PSA. So the CCF data of CANDU plants should be collected and incorporated into CANDU PSA

  9. (234)U/(238)U signatures associated with uranium ore bodies: part 3 Koongarra.

    Lowson, Richard T

    2013-04-01

    The Koongarra ore body is an early Proterozoic U ore body in the Alligator Rivers U province, Northern Territory, Australia. It has surface expression with a redox front located ∼30 m below the surface. The (234)U/(238)U activity ratios (AR) for the ground water and the amorphous phase of the solid have been analysed for the ore zone and dispersion halo as a function of depth. The results display a (234)U/(238)U AR signature with depth which may be common to all U ore bodies. The (234)U/(238)U AR is depressed below secular equilibrium in the weathered material above the redox front; rises significantly above secular equilibrium in the vicinity of the redox front; and is followed by a gradual decrease with depth below the redox front. The amplitude of the profile is a function of local conditions. A model is proposed for the signature in which oxidising waters preferentially leach the (234)U sites at the redox front due to preconditioning of the (234)U sites by α recoil during the decay of (23)(8)U to (23)(4)U. Mass balance requires the solid material left behind the redox front to have a (234)U/(238)U AR reduced below 1. Local second order effects may be superimposed on the signature. The signature may have application to calibrating scenarios for nuclear waste repositories, assisting in understanding historical climates, economic evaluation of U ore bodies and U exploration. PMID:23142336

  10. Residual β activity of particulate (234)Th as a novel proxy for tracking sediment resuspension in the ocean.

    Lin, Wuhui; Chen, Liqi; Zeng, Shi; Li, Tao; Wang, Yinghui; Yu, Kefu

    2016-01-01

    Sediment resuspension occurs in the global ocean, which greatly affects material exchange between the sediment and the overlying seawater. The behaviours of carbon, nutrients, heavy metals, and other pollutants at the sediment-seawater boundary will further link to climate change, eutrophication, and marine pollution. Residual β activity of particulate (234)Th (RAP234) is used as a novel proxy to track sediment resuspension in different marine environments, including the western Arctic Ocean, the South China Sea, and the Southern Ocean. Sediment resuspension identified by high activity of RAP234 is supported by different lines of evidence including seawater turbidity, residence time of total (234)Th, Goldschmidt's classification, and ratio of RAP234 to particulate organic carbon. A conceptual model is proposed to elucidate the mechanism for RAP234 with dominant contributions from (234)Th-(238)U and (212)Bi-(228)Th. The 'slope assumption' for RAP234 indicated increasing intensity of sediment resuspension from spring to autumn under the influence of the East Asian monsoon system. RAP234 can shed new light on (234)Th-based particle dynamics and should benefit the interpretation of historical (234)Th-(238)U database. RAP234 resembles lithophile elements and has broad implications for investigating particle dynamics in the estuary-shelf-slope-ocean continuum and linkage of the atmosphere-ocean-sediment system. PMID:27252085

  11. Residual β activity of particulate 234Th as a novel proxy for tracking sediment resuspension in the ocean

    Lin, Wuhui; Chen, Liqi; Zeng, Shi; Li, Tao; Wang, Yinghui; Yu, Kefu

    2016-01-01

    Sediment resuspension occurs in the global ocean, which greatly affects material exchange between the sediment and the overlying seawater. The behaviours of carbon, nutrients, heavy metals, and other pollutants at the sediment-seawater boundary will further link to climate change, eutrophication, and marine pollution. Residual β activity of particulate 234Th (RAP234) is used as a novel proxy to track sediment resuspension in different marine environments, including the western Arctic Ocean, the South China Sea, and the Southern Ocean. Sediment resuspension identified by high activity of RAP234 is supported by different lines of evidence including seawater turbidity, residence time of total 234Th, Goldschmidt’s classification, and ratio of RAP234 to particulate organic carbon. A conceptual model is proposed to elucidate the mechanism for RAP234 with dominant contributions from 234Th-238U and 212Bi-228Th. The ‘slope assumption’ for RAP234 indicated increasing intensity of sediment resuspension from spring to autumn under the influence of the East Asian monsoon system. RAP234 can shed new light on 234Th-based particle dynamics and should benefit the interpretation of historical 234Th-238U database. RAP234 resembles lithophile elements and has broad implications for investigating particle dynamics in the estuary-shelf-slope-ocean continuum and linkage of the atmosphere-ocean-sediment system. PMID:27252085

  12. Residual β activity of particulate 234Th as a novel proxy for tracking sediment resuspension in the ocean

    Lin, Wuhui; Chen, Liqi; Zeng, Shi; Li, Tao; Wang, Yinghui; Yu, Kefu

    2016-06-01

    Sediment resuspension occurs in the global ocean, which greatly affects material exchange between the sediment and the overlying seawater. The behaviours of carbon, nutrients, heavy metals, and other pollutants at the sediment-seawater boundary will further link to climate change, eutrophication, and marine pollution. Residual β activity of particulate 234Th (RAP234) is used as a novel proxy to track sediment resuspension in different marine environments, including the western Arctic Ocean, the South China Sea, and the Southern Ocean. Sediment resuspension identified by high activity of RAP234 is supported by different lines of evidence including seawater turbidity, residence time of total 234Th, Goldschmidt’s classification, and ratio of RAP234 to particulate organic carbon. A conceptual model is proposed to elucidate the mechanism for RAP234 with dominant contributions from 234Th-238U and 212Bi-228Th. The ‘slope assumption’ for RAP234 indicated increasing intensity of sediment resuspension from spring to autumn under the influence of the East Asian monsoon system. RAP234 can shed new light on 234Th-based particle dynamics and should benefit the interpretation of historical 234Th-238U database. RAP234 resembles lithophile elements and has broad implications for investigating particle dynamics in the estuary-shelf-slope-ocean continuum and linkage of the atmosphere-ocean-sediment system.

  13. Human reliability analysis in Wolsong 2/3/4 nuclear power plants probabilistic safety assessment

    The Level 1 probabilistic safety assessment (PSA) for Wolsong(WS) 2/3/4 nuclear power plant(NPPs) in design stage is performed using the methodologies being equivalent to PWR PSA. Accident sequence evaluation program (ASEF) human reliability analysis (HRA) procedure and technique for human error rate prediction (THERP) are used in HRA of WS 2/3/4 NPPs PSA. The purpose of this paper is to introduce the procedure and methodology of HRA in WS 2/3/4 NPPs PSA. Also, this paper describes the interim results of importance analysis for human actions modeled in WS 2/3/4 PSA and the findings and recommendations of administrative control of secondary control area from the view of human factors

  14. Dissolution behaviour of 238U, 234U and 230Th deposited on filters from personal dosemeters

    Kinetics of dissolution of 238U, 234U and 230Th dust deposited on filters from personal alpha dosemeters was studied by means of a 26-d in vitro dissolution test with a serum ultra-filtrate simulant. Dosemeters had been used by miners at the uranium mine 'Dolni Rozinka' at Rozna, Czech Republic. The sampling flow-rate as declared by the producer is 4 l h-1 and the sampling period is typically 1 month. Studied filters contained 125 ± 6 mBq 238U in equilibrium with 234U and 230Th; no 232Th series nuclides were found. Half-time of rapid dissolution of 1.4 d for 238U and 234U and slow dissolution half-times of 173 and 116 d were found for 238U and 234U, respectively. No detectable dissolution of 230Th was found. (authors)

  15. An Optimization Model for Design of Asphalt Pavements Based on IHAP Code Number 234

    Ali Reza Ghanizadeh

    2016-01-01

    Pavement construction is one of the most costly parts of transportation infrastructures. Incommensurate design and construction of pavements, in addition to the loss of the initial investment, would impose indirect costs to the road users and reduce road safety. This paper aims to propose an optimization model to determine the optimal configuration as well as the optimum thickness of different pavement layers based on the Iran Highway Asphalt Paving Code Number 234 (IHAP Code 234). After deve...

  16. 234Th/238U disequilibrium and particulate organic carbon export in the northern South China Sea

    We utilized 234Th, a naturally occurring radionuclide, to quantify the particulate organic carbon (POC) export rates in the northern South China Sea (SCS) based on data collected in July 2000 (summer), May 2001 (spring) and November 2002 (autumn). Th-234 deficit was enhanced with depth in the euphotic zone, reaching a sub-surface maximum at the Chl-a maximum in most cases, as commonly observed in many oceanic regimes. Th-234 was in general in equilibrium with 238U at a depth of ∼100 m, the bottom of the euphotic zone. In this study the 234Th deficit appeared to be less significant in November than in July and May. A surface excess of 234Th relative to 238U was found in the summer over the shelf of the northern SCS, most likely due to the accumulation of suspended particles entrapped by a salinity front. Comparison of the 234Th fluxes from the upper 10 m water column between 2-D and traditional 1-D models revealed agreement within the errors of estimation, suggesting the applicability of the 1-D model to this particular shelf region. 1-D model-based 234Th fluxes were converted to POC export rates using the ratios of bottle POC to 234Th. The values ranged from 5.3 to 26.6 mmol C m-2d-1 and were slightly higher than those in the southern SCS and other oligotrophic areas. POC export overall showed larger values in spring and summer than in autumn, the seasonality of which was, however, not significant. The highest POC export rate (26.6 mmol C m-2d-1) appeared at the shelf break in spring (May), when Chl-a increased and the community structure changed from pico-phytoplankton (<2 μm) dominated to nano-phytoplankton (2-20 μm) and micro-phytoplankton (20-200 μm) dominated. (author)

  17. Testing a new small-volume technique for determining 234Th in seawater

    Thorium-234 is a naturally occurring radionuclide that has been widely studied in ocean sciences. These studies use the disequilibrium between the soluble parent uranium-238 (T1/2 = 4.5 x 109 y ), and its particle reactive daughter, 234Th (T1/2 = 24.1 d), to quantify the in--situ removal rates of 234Th on sinking particles. Additional experiments that test a new 2-1 procedure in which 234Th is co-scavenged with a MnO2 precipitate is presented. Unlike other techniques, this method can be easily applied at-sea with an overall precision and accuracy of ≤5%. Experiments have sought to elucidate the effects of delaying reagent addition and precipitate filtration, differences in sample bottle types, and issues related to sample backgrounds and 234Th particulate sampling. Most of these experiments were conducted using collected on repeated occupations of station ALOHA (22deg45.0'N,158deg00.0'W), 100km North of Oahu, Hawaii. (author)

  18. Understanding of 234U/238U activity ratio in groundwater of agricultural ecosystem

    This study was carried out to clarify the natural variation of 234U/238U ratio in groundwater of an agricultural ecosystem. Water samples were collected from 21 locations from Bathinda and Mansa districts, of Punjab state and analysed for uranium concentration and activity ratio of its isotopes. The activity concentration ratio of 234U/238U in the groundwater samples varied between 0.39-0.98 with a mean value of 0.86. The lower isotopic ratio (less than 1) of 234U/238U indicates higher dissolution rate of parent 238U. The results suggest that, most of the dissolved uranium in groundwater is derived from the surrounding host soil or bed rock rather than from anthropogenic input. (author)

  19. Recent measurements of 234U/238U isotope ratio in spring waters from the Hadzici area.

    Vidic, Alfred; Ilić, Zorana; Benedik, Ljudmila

    2013-06-01

    The Hadzici area has become interesting for investigation since depleted uranium ammunition had been employed in 1995 during the NATO air strike campaign in Bosnia and Herzegovina. The purpose of this study is to determine uranium concentration and (234)U/(238)U activity ratio in the spring waters of this area and to investigate their relationship, as well as spatial variations. The spring water samples were taken at 18 sites in total. For the determination of uranium radioisotopes, radiochemical separation procedure followed by alpha-particle spectrometry was applied. Uranium concentration in analyzed waters range from 0.15 to 1.12 μg/L. Spring waters from carbonate based sediments have a lower uranium concentration of between 0.15 and 0.43 μg/L, in comparison to waters sampled within sandstone-based sediments ranging from 0.53 to 1.12 μg/L. Dissolved uranium shows significant spatial variability and correlation with bedrock type confirmed by Principal Component Analysis and Hierarchical Cluster Analysis. The majority of the analyzed waters have a (234)U/(238)U activity ratio ranging from 1.02 to 1.90, of which half of the results range between 1.02 and 1.16. No apparent depleted uranium (DU) contamination was observed, as (234)U/(238)U activity ratio is dependent on geochemical conditions in the environment. Even though the tested spring waters demonstrate significant variability in uranium concentration, (234)U/(238)U activity ratio and (234)U excess, waters with similar uranium isotopic signatures are observable within the region. The guidelines on the spatial redistribution of dissolved uranium (corresponding to (238)U mass concentration), along with (234)U/(238)U activity ratios were provided by the Inverse Distance Weighting (IDW) method. Waters having similar isotopic signature have been delineated. PMID:23410592

  20. Activity disequilibrium between 234U and 238U isotopes in natural environment

    The aim of this work was to calculate the values of the 234U/238U activity ratio in natural environment (water, sediments, Baltic organisms and marine birds from various regions of the southern Baltic Sea; river waters (the Vistula and the Oder River); plants and soils collected near phosphogypsum waste heap in Wislinka (Northern Poland) and deer-like animals from Northern Poland. On the basis of the studies it was found that the most important processes of uranium geochemical migration in the southern Baltic Sea ecosystem are the sedimentation of suspended material and the vertical diffusion from the sediments into the bottom water. Considerable values of the 234U/238U are characterized for the Vistula and Oder Rivers and its tributaries. The values of the 234U/238U activity ratio in different tissues and organs of the Baltic organisms, sea birds and wild deer are varied. Such a large variation value of obtained activity ratios indicates different behavior of uranium isotopes in the tissues and organisms of sea birds and wild animals. This value shows that uranium isotopes can be disposed at a slower or faster rate. The values of the 234U/238U activity ratio in the analyzed plants, soils and mosses collected in the vicinity of phosphogypsum dumps in Wislinka are close to one and indicate the phosphogypsum origin of the analyzed nuclides. Uranium isotopes 234U and 238U are not present in radioactive equilibrium in the aquatic environment, which indicates that their activities are not equal. The inverse relationship is observed in the terrestrial environment, where the value of the of the 234U/238U activity ratio really oscillates around unity. (author)

  1. Radionuclides of 210Po, 234U and 238U in drinking bottled mineral water in Poland

    A study of the radioactive content of drinking mineral bottled water in Poland was carried out. 210Po, 238U and 234U activity concentrations were determined by alpha-spectrometry with low-level-activity silicon detectors. The results revealed that the mean concentration of 210Po, 238U and 234U in analyzed water sample were 1.28, 0.80 and 0.80 mBq x dm-3, respectively. The effective doses due to the polonium and uranium emissions were calculated for bottled drinking water. (author)

  2. 234Th-derived particulate organic carbon export in the Prydz Bay, Antarctica

    234Th activities in sea water were measured using Fe(OH)3 co-precipitation and beta counting at six stations in Prydz Bay in March 2008 during the 24th Chinese National Antarctic Research Expedition. Total 234Th activities ranged from 0.96 to 2.44 dpm L-1 with an average of 1.61 dpm L-1, showing an apparent deficit with respect to 238U due to scavenging and export with particles. With a one-dimensional steady state model, 234Th export fluxes were converted to particulate organic carbon (POC) export using bottle ratios of POC concentrations to particulate 234Th activities on suspended particles. POC fluxes at the depth of 100 m varied between 33 and 297 mmol m-2 day-1, comparable to prior work in the same region and higher than those of some other sea areas in the Southern Ocean, and indicated efficient running of biological pump in Prydz Bay. The results could be helpful to expand the knowledge of carbon cycle in seasonally ice-covered coastal regions around Antarctica. (author)

  3. 43 CFR 2.34 - Where can I get a copy of DOI's FOIA annual report?

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Where can I get a copy of DOI's FOIA... AND TESTIMONY; FREEDOM OF INFORMATION ACT FOIA Annual Report § 2.34 Where can I get a copy of DOI's FOIA annual report? Under 5 U.S.C. 552(e), DOI is required to prepare an annual report regarding...

  4. 234U/238U activity ratio in groundwater - an indicator of past hydrogeological processes

    In this report we describe the long-term behaviour of the uranium isotopes, U-234 and U-238 in groundwater systems. U is a redox sensitive element what for its behaviour is largely controlled by changes in the environmental conditions. A striking feature in U isotope geochemistry is seemingly different behaviour of U-238 and U-234. U isotopes fractionate at the rock-groundwater interface depending on chemical and radiological factors. Changes of the redox conditions in groundwater may thus affect the behaviour of U and its isotopes resulting in variable U concentration and U-234/U-238 activity ratios (AR). We examined the formation of ARs in different groundwater types from a geochemical and a physical/radiological point of view. It was envisaged that AR in groundwater is the consequence of radiological, chemical and hydrological processes. Groundwater condition (redox, flow, etc.) play a very important role in controlling the mass flow of U isotopes. Quantitative α-recoil modelling showed that α-recoil induced flux can be considered insignificant in cases of high-flow. This was an important finding because the exclusion of direct a-recoil means that it is groundwater chemistry and its variations which controls the U-234 mass flow and the formation of AR. Therefore, AR values could be used more confidently to indicate past redox changes and possibly flow paths. (orig.)

  5. 20 CFR 234.14 - Payment to an equitably entitled person.

    2010-04-01

    ... RETIREMENT ACT LUMP-SUM PAYMENTS Lump-Sum Death Payment § 234.14 Payment to an equitably entitled person. (a) An equitably entitled person's funds used to pay burial expenses may consist of: (1) The individual's... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Payment to an equitably entitled person....

  6. 20 CFR 234.61 - Assignment of interest by an eligible person.

    2010-04-01

    ... RETIREMENT ACT LUMP-SUM PAYMENTS Miscellaneous § 234.61 Assignment of interest by an eligible person. (a) Any person who is eligible to receive a share of a lump-sum payment may assign his or her share to another... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Assignment of interest by an eligible...

  7. Uses of uranium isotopes 234U and 238U in hydrology and hydrogeology

    This work describes the application of the uranium isotopes 234U, 238U as a practically usuable indicator in hydrology and hydrogeology as well as its value in scientific research. The emphasis is laid on the methods of interpretation of U-data and the application of these methods to special hydrologic and hydrogeologic problems in the GDR. (author)

  8. 49 CFR 234.11 - State highway-rail grade crossing action plans.

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false State highway-rail grade crossing action plans... RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS Reports and Plans § 234.11 State highway-rail grade crossing action plans. (a) Purpose....

  9. 49 CFR 234.271 - Insulated rail joints, bond wires, and track connections.

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Insulated rail joints, bond wires, and track...) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS Maintenance, Inspection, and Testing Inspections and Tests § 234.271 Insulated...

  10. 14 CFR 234.10 - Voluntary disclosure of on-time performance codes.

    2010-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS AIRLINE SERVICE QUALITY PERFORMANCE REPORTS § 234.10 Voluntary disclosure of on-time performance codes. (a) Any air carrier may determine, in accordance with the provisions... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Voluntary disclosure of on-time...

  11. 14 CFR 234.9 - Reporting of on-time performance codes.

    2010-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS AIRLINE SERVICE QUALITY PERFORMANCE REPORTS § 234.9 Reporting of... deliver, or arrange to have delivered, to each system vendor, as defined in 14 CFR part 255, the on-time... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Reporting of on-time performance codes....

  12. 14 CFR 234.8 - Calculation of on-time performance codes.

    2010-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS AIRLINE SERVICE QUALITY PERFORMANCE REPORTS § 234.8 Calculation of on-time performance codes. (a) Each reporting carrier shall calculate an on-time performance code... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Calculation of on-time performance...

  13. 18 CFR 367.2340 - Account 234, Accounts payable to associate companies.

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Account 234, Accounts... COMPANY ACT OF 2005, FEDERAL POWER ACT AND NATURAL GAS ACT UNIFORM SYSTEM OF ACCOUNTS FOR CENTRALIZED... POWER ACT AND NATURAL GAS ACT Balance Sheet Chart of Accounts Current and Accrued Liabilities §...

  14. 50 CFR 23.4 - What are Appendices I, II, and III?

    2010-10-01

    ... FLORA (CITES) Introduction § 23.4 What are Appendices I, II, and III? Species are listed by the Parties... permits and certificates (CITES documents). Such documents enable Parties to monitor the effects of the... appearance to other related CITES species. (c) Appendix III includes species listed unilaterally by a...

  15. 230Th/234U dating of coral limestones and vertical uplift at Djibouti

    Coral limestones sampled from marine terraces along the Afar coast have been dated by the 230Th/234U method. The ages confirm the stratigraphic unity of these formations and the existence of the paleo sea level dated 124 000 years ago in this region. These results permit to deduce the uplift rates of this littoral

  16. Recent measurements of 234U/238U isotope ratio in spring waters from the Hadzici area

    The Hadzici area has become interesting for investigation since depleted uranium ammunition had been employed in 1995 during the NATO air strike campaign in Bosnia and Herzegovina. The purpose of this study is to determine uranium concentration and 234U/238U activity ratio in the spring waters of this area and to investigate their relationship, as well as spatial variations. The spring water samples were taken at 18 sites in total. For the determination of uranium radioisotopes, radiochemical separation procedure followed by alpha-particle spectrometry was applied. Uranium concentration in analyzed waters range from 0.15 to 1.12 μg/L. Spring waters from carbonate based sediments have a lower uranium concentration of between 0.15 and 0.43 μg/L, in comparison to waters sampled within sandstone-based sediments ranging from 0.53 to 1.12 μg/L. Dissolved uranium shows significant spatial variability and correlation with bedrock type confirmed by Principal Component Analysis and Hierarchical Cluster Analysis. The majority of the analyzed waters have a 234U/238U activity ratio ranging from 1.02 to 1.90, of which half of the results range between 1.02 and 1.16. No apparent depleted uranium (DU) contamination was observed, as 234U/238U activity ratio is dependent on geochemical conditions in the environment. Even though the tested spring waters demonstrate significant variability in uranium concentration, 234U/238U activity ratio and 234U excess, waters with similar uranium isotopic signatures are observable within the region. The guidelines on the spatial redistribution of dissolved uranium (corresponding to 238U mass concentration), along with 234U/238U activity ratios were provided by the Inverse Distance Weighting (IDW) method. Waters having similar isotopic signature have been delineated. -- Highlights: ► Uranium concentration in analyzed spring waters ranges from 0.15 to 1.12 μg/L. ► Dissolved uranium shows correlation with bedrock type. ► Low 234U/238U

  17. Role of colloids in upper ocean biogeochemistry in the northeast Pacific Ocean elucidated from 238U-234Th disequilibria

    Detailed upper ocean profiles of 234Th is dissolved (0.45 μm) forms were measured at a station (46 degrees 45'N, 126 degrees W) in the northeast Pacific Ocean. On average, dissolved, colloidal, and particulate 234Th accounted for ∼ 78, 12 and 10% of the total 234Th in the euphotic zone (0-100 m). A highly positive correlation exists between colloidal 234Th and chlorophyll α; both are characterized by higher concentrations in surface waters, a subsurface maximum at 5 m in the seasonal thermocline, and undetectable levels below the euphotic zone. POC: Chl α ratios in the water column suggest phytoplankton as primary producers of the colloidal material. Scavenging residence times of dissolved, colloidal, and particulate 234Th with respect to their removal processes in the euphotic zone are ∼50, 6, and 8 d. The scavenging rate constant of Th apparently increases with the concentration of colloids. 23 refs., 3 figs., 1 tab

  18. Quantification of 234 Th recovery in small volume sea water samples by inductively coupled plasma-mass spectrometry

    Development of a small volume (2-4 liter) technique for measuring 234 Th in sea water has been instrumental in bringing to light small-scale structures in upper-ocean particle removal processes previously missed by standard 234Th measurement techniques. Further development of this method to evaluate removal efficiencies of 234Th via MnO2 precipitation quantified using ICP-MS are presented in this work. Advantages to this approach are precise knowledge of 234Th recovery, while maintaining high sample throughput afforded by ICP-MS analyzes. The improved technique includes the acidification of 4-liter sea water samples and the addition of 230Th as a yield monitor prior to MnO2 precipitation. Subsequent filtration and beta-counting of the high-energy daughter, 234mPa, was followed by a final background count after 6 half-lives (144 d) of decay. Filtered precipitates were dissolved with H2O2, and an internal standard of 229Th was added. Samples were purified using anion-exchange chromatography to remove high levels of manganese, and recoveries were determined by measured ratios of 230Th/229 Th by ICP-MS. Application of this procedure for 234Th derived export in the recent Southern Ocean Iron Experiment showed average recoveries of 91%. Corrections for rare low recoveries (25-80%) noticeably change 234Th profiles, thus impacting subsequent elemental flux calculations. (author)

  19. The inflow of 234U and 238U from the River Odra drainage basin to the Baltic Sea

    Bogdan Skwarzec

    2010-12-01

    Full Text Available In this study the activity of uranium isotopes 234U and 238U in Odra river water samples, collected from October 2003 to July2004, was measured using alpha spectrometry. The uranium concentrations were different in each of the seasons analysed; the lowest values were recorded in summer. In all seasons, uranium concentrations were the highest in Bystrzyca river waters (from 27.81 ± 0.29Bq m-3 of 234U and 17.82 ± 0.23 Bq m-3 of 238U in spring to 194.76 ± 3.43 Bq m-3 of 234U and 134.88 ± 2.85 Bq m-3 of 238U in summer. The lowest concentrations were noted in the Mała Panew (from 1.33 ± 0.02 Bq m-3 of 234U and 1.06 ± 0.02 Bq m-3 of 238U in spring to 3.52 ± 0.05 Bq m-3 of 234U and 2.59± 0.04 Bq m-3 of 238U in autumn. The uranium radionuclides 234U and 238U in the water samples were not in radioactive equilibrium. The 234U / 238U activity ratios were the highest in Odra water samples collected at Głogów (1.84 in autumn, and the lowest in water from the Noteć (1.03 in winter and spring. The 234U / 238U activity ratio decreases along the main stream of the Odra, owing to changes in the salinity of the river's waters. Annually, 8.19 tons of uranium (126.29 G Bq of 234U and 100.80 G Bq of 238U flow into the Szczecin Lagoon with Odra river waters.

  20. Treatment of 234 Cases of Dementia due to Cerebrovascular Disease by Acupoint Injection

    ZHAO Bao-yu; YUE Xiu-lan; FU Bao-zhen; CUI Xue-jun

    2003-01-01

    Objective To observe the effect of acupoint-injection on vascular dementia. Methods 1 ml of cytidine diphosphocholine was injected into Baihui ( GV 20) and Fengchi (GB 20, bilateral) respectively. 234 patients were treated. Results and conclusion: 49 cases were cured, 150 cases got improve, 35 cases had ineffectiveness, the total utility rate was 85.0%, so acupoint-injecting cytidine diphosphocholine is a utility method healing vascular dementia.

  1. Round-robin 230Th-234U age dating of bulk uranium for nuclear forensics

    In an inter-laboratory measurement comparison study, four laboratories determined 230Th-234U model ages of uranium certified reference material NBL U050 using isotope dilution mass spectrometry. The model dates determined by the participating laboratories range from 9 March 1956 to 19 October 1957, and are indistinguishable given the associated measurement uncertainties. These model ages are concordant with to slightly older than the known production age of NBL U050. (author)

  2. Measurement of the neutron capture cross section of 234U in n-TOF at CERN

    Accurate and reliable neutron capture cross sections are needed in many research areas, including stellar nucleosynthesis, advanced nuclear fuel cycles, waste transmutation, and other applied programs. In particular, the accurate knowledge of 234U(n, γ) reaction cross section is required for the design and realization of nuclear power stations based on the thorium fuel cycle. We have measured the neutron capture cross section of 234U at the recently constructed neutron time-of-flight facility n-TOF at CERN [2] in the energy range from 0.03 eV to 1 MeV with high accuracy due to a combination of features unique in the world: A high instantaneous neutron fluence and excellent energy resolution of the n-TOF facility, an innovative Data Acquisition System based on flash ADCs [3] and the use of a high performance 4Π BaF2 Total Absorption Calorimeter (TAC) as a detection device [4, 5], In this paper, we will describe the experimental apparatus including the various TAC components and its performance. We also will present results from the 234U(n, γ) measurement. A sample of 38.7 mg of 234U3O8 was pressed into a pellet and doubly encapsulated between Al and Ti foils which were 0.15 mm and 0.2 mm thick, respectively. Monte-Carlo simulations with GEANT4 [6] of the detector response have been performed. After the background subtraction and correction with dead time and pile-up, the capture yield from 0.03 eV up to 1.5 keV was derived. Preliminary analysis of the capture yield in terms of R-matrix resonance parameters is discussed. (authors)

  3. Residence times of 234Th and 7Be in Lake Geneva

    Dominik, J.; Schuler, Ch.; Santschi, P. H.

    1989-07-01

    The activities of two short-lived natural radionuclides, 234Th and 7Be, were measured in Lake Geneva water, suspended solids and sediments, in order to obtain their removal residence times in the lake. Four independent methods of estimation are presented and compared. The calcuated residence times of 234Th and 7Be vary from 60 to 280 days and from 60 to 1100 days, respectively, depending on season and the method used. In general, 7Be residence times are significantly longer than those of 234Th. For both nuclides the removal residence times are significantly longer than their respective radioactive mean-lives. As a consequence, the estimates based on their water column inventories are not as reliable as the estimates obtained from the measured fluxes of these nuclides into sediment traps. Estimates based on the bottom sediment inventories are similar in magnitude to those obtained from flux into sediment traps, but occasionally are erroneous because of small-scale sediment heterogeneity.

  4. Rates of sediment reworking at the HEBBLE site based on measurements of Th-234, Cs-137 and Pb-210

    Th-234, Cs-137 and Pb-210 measurements have been made on ten cores from the HEBBLE site on the Nova Scotian continental rise. Th-234 mixing coefficients from HEBBLE sediments show substantial lateral variability with values ranging from 1 to 33 cm2 yr-1. These mixing coefficients are one to two orders of magnitude greater than values from typical continental-rise and abyssal sediments because of high densities of benthic macrofauna. Th-234 data from HEBBLE cores indicate that particles at the sediment-water interface are mixed to depths of 1-5 cm on a 100-day time scale. Cs-137 and Pb-210 data indicate that on time scales of 30-100 yrs surface sediments are reworked to depths ranging from 1 to 12 cm. Based on Th-234 profiles from two HEBBLE cores collected less than 200 m apart during consecutive years, no temporal variability in mixing rate could be resolved. (Auth.)

  5. Precise measurements of 234U/238U and U concentrations in profiles of Pacific and Atlantic waters

    High precision measurement of 234U/238U ratios and U concentrations in profiles of Atlantic and Pacific waters have been made in order to determine the degree of heterogeneity of these parameters in the open ocean. The measurements were made possible by the development of mass spectrometric techniques to measure 234U/238U to +/- ∼ 5 per thousand (2σ) and U concentrations to +/- 2 per thousand with 2-5 x 109 atoms of 234U. A 233U-236U double spike is used to correct for instrumental mass fractionation. The average 234U/238U for 4 samples from the Pacific profile is 144 +/- 4 per thousand higher than the equilibrium atomic 234U/238U ratio (5.47 x 10-5). The average for 5 samples in the Atlantic profile is identical (144 +/- 4 per thousand). A comparison of 234U/238U values for samples above and below the thermocline shows similar homogeneity. U concentrations normalized to 35 per thousand salinity are the same within ∼ 1% (3.215 +/- 6 to 3.257 +/- 6 ppb) but clearly show variation greater than the +/- 2 per thousand error. The reason for this fine scale variation requires further investigation. The authors data suggest that 234U/238U in the open ocean is homogeneous to within 8 per thousand. This is consistent with the long residence time of U and the long 234U half life compared to the residence time of water in the deep ocean. Similar measurements on marine pore fluids which can easily be done using the authors technique should provide constraints on the U flux across the sediment-water interface

  6. High-precision determination of 234U/238U activity ratios in natural waters and carbonates by ICPMS

    A method has been developed for precise measurement of 234U/238U activity ratios in natural waters and carbonates using quadrupole inductively coupled plasma mass spectrometry. A recovery of 80--85% of seawater U is achieved by Fe(III) coprecipitation followed by extraction chromatography with a supported dipentyl pentane phosphonate material; 90--95% of U is recovered from carbonates, which are dissolved in HNO3 and subjected to the same extraction chromatographic preparation. Isotopic measurements are made via recirculating pneumatic nebulization of small volumes of solutions containing 0.5--5 mg/L U. 234U/235U is measured as a proxy for determination of 234U/238U; iridium is added to sample solutions and the ion ratio 191Ir40Ar+/193Ir40Ar+ is measured for internal mass discrimination correction 234U/238U activity ratios in the range 1.143--1.154 are observed for 13 seawater and contemporary corals, in agreement with the established marine 234U/238U activity ratio. For samples sizes of 5--25 microg U, ICPMS uncertainties of ± 0.2--0.5% relative, 2θ standard error, approach those obtained for 234U/238U activity ratios in bottled waters, Lake Erie surface waters, mollusk fossils, and fertilizers are also demonstrated

  7. The inflow of uranium 234U and 238U from the Vistula River catchment area to the Baltic Sea

    In the study, the activities of uranium 234U and 238U in the Vistula River water samples which were collected from November 2002 to October 2003, were measured using alpha spectrometry. In winter, the highest concentration of uranium isotopes and total uranium was in the Vistula River water from Malbork (13.13 ± 0.22 Bq m-3 for 234U, 12.45 ± 0.21 Bq m-3 for 238U and 1.02 ± 0.30 mg m-3 for total uranium), and the lowest was in water from Deblin (1.73 ± 0.07 Bq m-3 for 234U, 1.55 ± 0.07 Bq m-3 for 238U and 0.13 ± 0.09 mg m-3 for total uranium). In analyzed river samples uranium isotopes 234U and 238U are not in the radioactive equilibrium state. The values of 234U/238U activity ratio lie between 1.05-1.70. During spring, the highest concentration of uranium isotopes and total uranium was found in the Vistula River water from Malbork (12.36 ± 0.19 Bq m-3 for 234U, 10.77 ± 0.17 Bq m-3 for 238U and 0.88 ± 0.25 mg m-3 for total uranium), and the lowest was in water taken from Sandomierz (5.77 ± 0.14 Bq m-3 for 234U) and Krakow (4.08 ± 0.11 Bq m-3 for 238U and 0.33 ± 0.18 mg m-3 for total uranium). The values of 234U/238U activity ratio lie between 1.15-1.64. In summer, the highest concentration of uranium isotopes and total uranium was found in the Vistula River water samples taken from Malbork (8.22 ± 0.21 Bq m-3 for 234U, 7.60 ± 0.21 Bq m-3 for 238U and 0.62 ± 0.29 mg m-3 for total uranium), and the lowest was in water from Sandomierz (6.37 ± 0.12 Bq m-3 for 234U) and Krakow (3.56 ± 0.19 Bq m-3 for 238U and 0.29 ± 0.33 mg m-3 for total uranium). The values of 234U/238U activity ratio lie between 1.08-1.95. In autumn the highest concentration of uranium isotopes and total uranium was in the Vistula River water from Malbork (17.80 ± 0.25 Bq m-3 for 234U, 15.12 ± 0.23 Bq m-3 for 238U and 1.23 ± 0.34 mg m-3 for total uranium) and the lowest was in water from Torun (8.15 ± 0.49 Bq m-3 for 234U) and Krakow (6.34 ± 0.47 Bq m-3 for 238U and 0.52 ± 0

  8. Investigation of 234U(n,f) as a Function of Incident Neutron Energy

    Al-Adili, A.; Hambsch, F.-J.; Oberstedt, S.; Pomp, S.

    2011-10-01

    Measurements of the reaction 234U(n,f) have been performed at incident neutron energies from 0.2 MeV to 5 MeV at the 7 MV Van De Graaf accelerator at IRMM. A twin Frisch-grid ionization chamber was used for fission-fragment detection. Parallel digital and analogue data acquisitions were applied in order to compare the two techniques. First results on the angular anisotropy and preliminary mass distributions are presented along with a first comparison between the two techniques.

  9. Study of 234U(n,f) Resonances Measured at the CERN n_TOF Facility

    Leal-Cidoncha, E; Paradela, C; Tarrío, D; Leong, L S; Audouin, L; Tassan-Got, L; Praena, J; Berthier, B; Ferrant, L; Isaev, S; Le Naour, C; Stephan, C; Trubert, D; Abbondanno, U; Aerts, G; Álvarez, H; Álvarez-Velarde, F; Andriamonje, S; Andrzejewski, J; Badurek, G; Baumann, P; Bečvář, F; Berthoumieux, E; Calviño, F; Calviani, M; Cano-Ott, D; Capote, R; Carrapiço, C; Cennini, P.; Chepel, V; Chiaveri, E.; Colonna, N; Cortes, G; Couture, A; Cox, J; Dahlfors, M; David, S.; Dillmann, I; Domingo-Pardo, C; Dridi, W; Eleftheriadis, C; Embid-Segura, M; Ferrari, A.; Ferreira-Marques, R; Fujii, K; Furman, W; Gonçalves, I; González-Romero, E; Gramegna, F; Guerrero, C; Gunsing, F; Haas, B; Haight, R; Heil, M; Herrera-Martinez, A.; Igashira, M; Jericha, E; Kadi, Y.; Käppeler, F; Karadimos, D; Kerveno, M; Koehler, P; Kossionides, E; Krtička, M; Lampoudis, C; Leeb, H; Lindote, A; Lopes, I; Lozano, M; Lukic, S; Marganiec, J; Marrone, S; Martínez, T; Massimi, C; Mastinu, P; Mengoni, A; Milazzo, P M; Moreau, C; Mosconi, M; Neves, F; Oberhummer, H; O'Brien, S; Oshima, M; Pancin, J; Papadopoulos, C; Pavlik, A; Pavlopoulos, P.; Perrot, L; Pigni, M T; Plag, R; Plompen, A; Plukis, A; Poch, A; Pretel, C; Quesada, J; Rauscher, T.; Reifarth, R; Rubbia, C.; Rudolf, G; Rullhusen, P; Salgado, J; Santos, C; Sarchiapone, L.; Savvidis, I; Tagliente, G; Tain, J L; Tavora, L; Terlizzi, R; Vannini, G; Vaz, P; Ventura, A.; Villamarin, D; Vincente, M C; Vlachoudis, V.; Vlastou, R; Voss, F; Walter, S; Wiescher, M; Wisshak, K

    2014-01-01

    We present the analysis of the resolved resonance region for the U-234(n,f) cross section data measured at the CERN n\\_TOF facility. The resonance parameters in the energy range from 1 eV to 1500 eV have been obtained with the SAMMY code by using as initial parameters for the fit the resonance parameters of the JENDL-3.3 evaluation. In addition, the statistical analysis has been accomplished, partly with the SAMDIST code, in order to study the level spacing and the Mehta-Dyson correlation.

  10. Investigation of 234U(n,f) with a Frisch-grid ionization chamber

    Al-Adili, Ali

    2011-01-01

    This work treats three topics. The main topic concerns neutron-induced fission of 234U. The main goal is to investigate the fission-fragments properties  as a function of the incident neutron energy. The study was carried out using a twin Frisch-grid ionization chamber. The first fluctuations on fragment properties are presented, in terms of strong angular anisotropy oscillation. The second part of the work treats the data-acquisition systems in use, particularly for neutron-induced fission e...

  11. Characterization and Purification a Specific Xylanase Showing Arabinofuranosidase Activity from Streptomyces spp. 234P-16

    ALINA AKHDIYA; FAHRRUROZI; TRIO HENDARWIN; ANJA MERYANDINI; DEDEN SAPRUDIN; YULIN LESTARI

    2009-01-01

    Streptomyces spp 234P-16 producing xylanase was isolated from soil sample from Padang, West Sumatra, Indonesia. Crude enzyme (produced by centrifuging the culture at 14000 rpm for about 5 minutes) and purified xylanase have an optimum condition at pH 5 and 90oC. Crude xylanase have half life time of 4 hours, whereas purified xylanase have half life time of 2 ½ hours at 90oC. The molecular mass of purified xylanase was determined to be 42.4 kDa. The Arabinofuranosidase have a Km and Vmax value...

  12. 232Th, 233Pa, and 234U capture cross-section measurements in moderated neutron flux

    The Th-U cycle was studied through the evolution of a 100 μg 232Th sample irradiated in a moderated neutron flux of 8.01014 n/cm2/s, intensity close to that of a thermal molten salt reactor. After 43 days of irradiation and 6 months of cooling, a precise mass spectrometric analysis, using both TIMS and MC-ICP-MS techniques, was performed, according to a rigorous methodology. The measured thorium and uranium isotopic ratios in the final irradiated sample were then compared with integral simulations based on evaluated data; an overall good agreement was seen. Four important thermal neutron-capture cross-sections were also extracted from the measurements, 232Th (7.34±0.21 b), 233Pa (38.34±1.78 b), 234U (106.12±3.34 b), and 235U (98.15±11.24 b). Our 232Th and 235U results confirmed existing values whereas the cross-sections of 233Pa and 234U (both key parameters) have been redefined

  13. Measurements of 234U, 238U and 230Th in excreta of uranium-mill crushermen

    Uranium and thorium levels in excreta of uranium mill crushermen who are routinely exposed to airborne uranium ore dust were measured. The purpose was to determine whether 230Th was preferentially retained over either 234U or 238U in the body. Urine and fecal samples were obtained from fourteen active crushermen with long histories of exposure to uranium ore dust, plus four retired crushermen and three control individuals for comparison. Radiochemical procedures were used to separate out the uranium and thorium fractions, which were then electroplated on stainless steel discs and assayed by alpha spectrometry. Significantly greater activity levels of 234U and 238U were measured in both urine and fecal samples obtained from uranium mill crushermen, indicating that uranium in the inhaled ore dust was cleared from the body with a shorter biological half-time than the daughter product 230Th. The measurements also indicated that uranium and thorium separate in vivo and have distinctly different metabolic pathways and transfer rates in the body. The appropriateness of current ICRP retention and clearance parameters for 230Th in ore dust is questioned

  14. Microscopic study of positive-parity yrast bands of 224−234Th isotopes

    Daya Ram; Rani Devi; S K Khosa

    2013-06-01

    The positive-parity bands in 224−234Th are studied using the projected shell model (PSM) approach. The energy levels, deformation systematics, (2) transition probabilities and nuclear -factors are calculated and compared with the experimental data. The calculation reproduces the observed positive-parity yrast bands and (2) transition probabilities. Measurement of (2) transition probabilities for higher spins and -factors would be a stringent test for our predictions. The results of theoretical calculations indicate that the deformation systematics in 224−234Th isotopes depend on the occupation of low components of high j orbits in the valence space and the deformation producing tendency of the neutron–proton interaction operating between spin orbit partner (SOP) orbits, the $[(2g_{9/2}_{}) - (2g_{7/2})_{}]$ and $[(1i_{13/2})_{} - (1i_{11/2})_{}]$ SOP orbits in the present context. In addition, the deformation systematics also depend on the polarization of $(1h_{11/2})_{}$ orbit. The low-lying states of yrast spectra are found to arise from 0-quasiparticle (qp) intrinsic states whereas the high-spin states turn out to possess composite structure.

  15. Measurement of absolute gamma ray emission probability of 1001 keV from the decay of 234mPa

    In the direct γ-ray spectrometric measurements of 238U content, 1001 keV γ-ray of 234mPa is commonly used in recent years. 234mPa is the second daughter of 238U and rapidly reaches secular equilibrium with the parent nucleus. This clean peak is well resolved by high purity Ge detectors and gives more accurate indication of uranium content without requiring any self attenuation correction. Several measurements of the absolute emission probability of the 1001 keV γ-ray of 234mPa have resulted in doubts concerning the old recommended value 0.59±0.01 % obtained by a radiochemical method. Therefore, this old value is now absolute and a newly value of 0.835±0.004 % is recommended. In this study the γ-ray spectrometric measurements were carried out using the powdered U3O8 and the certified uranium samples. A new experimental value o 0.861±0.015 % for the absolute γ-ray emission probability for the 1001 keV gamma-ray of the 234mPa has been obtained. The present measured values agrees good with the most experimental results appeared in the literature and is close to the newly recommended values of 0.835±0.004 % and 0.837±0.012 % for the 1001 keV γ-ray of 234mPa

  16. 238U, 234U, 226Ra, 210Po concentrations of bottled mineral waters in Italy and their dose contribution

    Due to the importance of bottled mineral water in human diet with special regard to children in lactation period, a monitoring of natural radioactivity in some bottled mineral waters produced in Italy was performed. Gross alpha and beta activities and 226Ra, 238U, 234U, and 210Po concentrations were measured. Gross alpha and beta activities were determined by standards ISO 9696 and ISO 9697; for 226Ra determination liquid scintillation was used. The 238U and 234U concentrations were determined by alpha spectrometry after their separation from matrix by extraction chromatography and electroplating. 210Po was measured by alpha spectrometry. The results revealed that the concentrations (mBq L-1) of 226Ra, 238U, 234U, and 210Po ranged from -1; for infants (-1

  17. Effect of the addition of ultraviolet absorber (Tinuvin 234) on the quality of soybean oil packaged in polyethylene terephthalate (PET)

    In this work, the effect of the addition of the UV absorber Tinuvin 234 on the quality of soybean oil packaged in PET bottles stored at ambient temperature for 6 months under fluorescent light (634 lux). Along this period determinations were made of: peroxide value (PV), free fatty acids (FFA), specific extinction at 232 and 270 nm (EE) and sensorial evaluation (SE). The analysis of variance and resistance between the linear coefficients of each treatment indicates that significant difference does not exist (p0.0001) during the storage in relation to all determinations (PV, FFA, EE and SE). The results indicate that the addition of the absorbent Tinuvin 234 to PET bottles in the concentrations of 0.12% and 0.22% was not efficient in slowing down the deterioration of the oil exposed to the fluorescent light, when compared with soybean oil in PET bottles without addition of Tinuvin 234. (author)

  18. The distribution of Uranium-234 excess in the MAILUU-SUU river due to uranium tail deposits localization

    Full text : It is shown in a series of papers that for solution of a problem of technogenic uranium component separation the phenomenon of natural separation of uranium-234 and uranium -238 can be used. The consequence of this is a different degree of 234U and 238U fractioning in natural conditions during technological processes. There is a real opportunity to distinguish the uranium of natural water from technogenic uranium of tail deposists and leaches from uranium dumps by a value of activitiesratio 234U/238U = lambda. This, in turn, allows revealing areas of technogenic uranium distribution in ground water. The advantage of non-equilibrium uranium for revealing space regularities of thecnogenic uranium migration around the tail deposists and dumps is evident because there are no any other indicators at present which would be able to solve the pointed problem

  19. Fragment properties from fission of 234,238U induced by 6 -10 MeV bremsstrahlung

    Experiments to investigate the photon-induced fission of actinide nuclei at excitation energies in the vicinity of the fission barrier are carried out at the super conducting Darmstadt linear electron accelerator S-DALINAC. A twin Frisch grid ionization chamber is used to deduce mass, total kinetic energy, and angular distributions of the fission fragments. In this contribution results on fission fragment mass and total kinetic energy distributions from 234,238U are presented along with the currently on-going investigation of 234U and 232Th fragment angular distributions.

  20. The 234U neutron capture cross section measurement at the n TOF facility

    The neutron capture cross-section of 234U has been measured for energies from thermal up to the keV region in the neutron time-of-flight facility n-TOF, based on a spallation source located at CERN. A 4π BaF2 array composed of 40 crystals, placed at a distance of 184.9 m from the neutron source, was employed as a total absorption calorimeter (TAC) for detection of the prompt γ-ray cascade from capture events in the sample. This text describes the experimental setup, all necessary steps followed during the data analysis procedure. Results are presented in the form of R-matrix resonance parameters from fits with the SAMMY code and compared to the evaluated data of Endf in the relevant energy region, indicating the good performance of the n-TOF facility and the TAC. (authors)

  1. The {sup 234}U neutron capture cross section measurement at the n TOF facility

    Lampoudis, C.; Abbondanno, U.; Aerts, G.; A lvarez, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Audouin, L.; Badurek, O.; Baumann, P.; Becvar, F.; Berthoumieux, E.; Calvino, F.; Calviani, M.; Cano-Ott, D.; Capote, R.; Carrapico, C.; Cennini, P.; Chepel, V.; Chiaveri, E.; Colonna, N.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Domingo-Pardo, C.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Ferreira-Marques, R.; Fujii, K.; Furman, W.; Goncalves, I.; Gonzalez-Romero, E.; Gramegna, F.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Jericha, E.; Kappeler, F.; Kadi, Y.; Karadimos, D.; Karamanis, D.; Kerveno, M.; Koehler, P.; Kossionides, E.; Krticka, M.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marrone, S.; Martinez, T.; Massimi, C.; Mastinu, P.; Mengoni, A.; Milazzo, P.M.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O' Brien, S.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Pigni, M.T.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Praena, J.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Santos, C.; Sarchiapone, L.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J.L.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M.C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wiescher, M.; Wisshak, K

    2008-07-01

    The neutron capture cross-section of {sup 234}U has been measured for energies from thermal up to the keV region in the neutron time-of-flight facility n-TOF, based on a spallation source located at CERN. A 4{pi} BaF{sub 2} array composed of 40 crystals, placed at a distance of 184.9 m from the neutron source, was employed as a total absorption calorimeter (TAC) for detection of the prompt {gamma}-ray cascade from capture events in the sample. This text describes the experimental setup, all necessary steps followed during the data analysis procedure. Results are presented in the form of R-matrix resonance parameters from fits with the SAMMY code and compared to the evaluated data of Endf in the relevant energy region, indicating the good performance of the n-TOF facility and the TAC. (authors)

  2. Whole-genome sequencing of 234 bulls facilitates mapping of monogenic and complex traits in cattle

    Daetwyler, Hans D; Capitan, Aurélien; Pausch, Hubert;

    2014-01-01

    The 1000 bull genomes project supports the goal of accelerating the rates of genetic gain in domestic cattle while at the same time considering animal health and welfare by providing the annotated sequence variants and genotypes of key ancestor bulls. In the first phase of the 1000 bull genomes...... project, we sequenced the whole genomes of 234 cattle to an average of 8.3-fold coverage. This sequencing includes data for 129 individuals from the global Holstein-Friesian population, 43 individuals from the Fleckvieh breed and 15 individuals from the Jersey breed. We identified a total of 28.3 million...... variants, with an average of 1.44 heterozygous sites per kilobase for each individual. We demonstrate the use of this database in identifying a recessive mutation underlying embryonic death and a dominant mutation underlying lethal chrondrodysplasia. We also performed genome-wide association studies for...

  3. Determination of the 234Pa(n, f) reaction cross section by hybrid surrogate ratio method

    In an earlier work, we employed a new hybrid surrogate ratio approach to determine the 233Pa(n, f) cross sections for the first time in the equivalent neutron energy range of 11.5 MeV to 16.5 MeV using 6Li + 232Th transfer-fission correlation measurements. The 234Pa isotope produced in thorium-uranium fuel cycle is having half-life of 6.8 hrs. There is no neutron induced fission cross section data available in the literature for this system. We report first time results on 243Pa(n, f) cross sections in the equivalent neutron energy range of 10.5 MeV to 15.5 MeV using 7Li + 232Th transfer-fission correlation measurements with in the framework of hybrid surrogate method

  4. Characterization and Purification a Specific Xylanase Showing Arabinofuranosidase Activity from Streptomyces spp. 234P-16

    ALINA AKHDIYA

    2009-07-01

    Full Text Available Streptomyces spp 234P-16 producing xylanase was isolated from soil sample from Padang, West Sumatra, Indonesia. Crude enzyme (produced by centrifuging the culture at 14000 rpm for about 5 minutes and purified xylanase have an optimum condition at pH 5 and 90oC. Crude xylanase have half life time of 4 hours, whereas purified xylanase have half life time of 2 ½ hours at 90oC. The molecular mass of purified xylanase was determined to be 42.4 kDa. The Arabinofuranosidase have a Km and Vmax value of 1,98 mg/mL and 523 µmol/minute/mg, respectively.

  5. Fission-Fragment Angular, Energy, and Mass Division Correlations for the U234 (d, Pf) Reaction

    The fission of the compound nucleus U235 in the neighbourhood of its fission threshold has been studied by means of the U234 (d.pf) reaction. A three-parameter analyser was used to record simultaneously the two fission-fragment kinetic energies and the proton energy for each coincident event. The excitation energy at which fission occurs is defined by the kinetic energy of the stripped.proton. The variation of angular anisotropy with excitation energy shows considerably more structure than that obtained by Lamphere for the same nucleus resulting from fast-neutron bombardment of U234. At least eight fission channels at the saddle point have been observed for the energy region between threshold and 2 MeV above threshold. Nilsson-type calculations of single particle energies for deformed nuclei have been made for the larger deformations more nearly describing the saddle-point configuration. The single particle states identified by Lamphere are consistent with those calculated to be close to the Fermi surface for reasonable saddle-point deformations. The primary motivation for this experiment was to search for a possible correlation between mass asymmetry and angular anisotropy. Mass yields obtained from the correlated fragment energies show no variation of the anisotropy with mass ratio, in contrast with experiments where the excitation energy at which fission is occurring is not fixed and where a dependence of anisotropy on mass ratio has been observed. There is therefore no evidence from anisotropy measurements that the properties of the saddle point influence the final mass division. The average total kinetic energy release in fission varies by less than 0.5% for the different saddle-point channels observed. The variation of total kinetic energy with mass ratio has also been investigated. (author)

  6. Inadequate-1D and dynamic NMR of mesoion 3-phenyl-1-thio-2,3,4-triazole-5-methylides; INADEQUATE-1D i dynamiczny NMR mezojonowych 3-fenylo-1-tio-2,3,4-triazolo-5-metylidow

    Bocian, W.; Stefaniak, L. [Inst. Chemii Organicznej, Polska Akademia Nauk, Warsaw (Poland)

    1994-12-31

    The chemical shifts and coupling constants have been measured in series of mesoionic triazoles by means of inadequate atoms and dynamic NMR techniques. The electronic structure and other parameters of C5-C6 chemical bond in different derivatives of mesoionic 3-phenyl-1-thio-2,3,4-triazole-5 methyls have been determined. 14 refs, 3 figs, 2 tabs.

  7. Performance and application research of the dense direct dyes formaldehyde-free fixing agent TF-234Y%直接染料无醛固色剂TF-234Y浓的性能及应用研究

    张红燕; 陈庆文; 沈立; 金鲜花; 吴彬

    2013-01-01

      A new concentrated direct dyes formaldehyde-free fixing agent TF-234Y was prepared in view of the existing problems in direct dyes fixing agents, the environmental protection and market demands in this paper. The test and analysis of the formaldehyde content, heavy metal ions content and aromatic amine content which can cause cancer etc. proved that the dense fixing agent TF-234Y contained no harmful substances. Experiment results showed that when the fixing agent was applied to the medium or deep color cotton knitted fabric and cotton/brocade/ammonia(80/18/2)blended fabric dyed with direct dyes, the dense fixing agent TF-234Y was able to bviously improve various color fastness and was more excellently than fixing agent Y. Especially the effect of the dense fixing agent TF-234Y on the handle and color change of after treated fabrics was much less than that of fixing agent Y.%  针对目前直接染料固色剂存在的问题以及环保、市场需求,制备出了直接染料无醛固色剂TF-234Y浓。通过对甲醛、重金属离子、致癌芳香胺等指标的检测分析,证实TF-234Y浓不含有害物质,用其对直接染料所染的中、深色棉织物、棉/锦/氨(80/18/2)混纺织物进行固色并检测固色后织物的综合性能,发现TF-234Y浓可以明显提升染色物的各项色牢度,其固色性能优于固色剂Y,尤其是对染色物的手感、色差变化的影响比固色剂Y要小得多。

  8. 33 CFR 2.34 - Waters subject to tidal influence; waters subject to the ebb and flow of the tide; mean high water.

    2010-07-01

    ...; waters subject to the ebb and flow of the tide; mean high water. 2.34 Section 2.34 Navigation and....34 Waters subject to tidal influence; waters subject to the ebb and flow of the tide; mean high water. (a) Waters subject to tidal influence and waters subject to the ebb and flow of the tide are...

  9. State of disequilibrium between 238U, 234U, 226Ra and 222Rn in groundwater from bedrock

    Approximately one thousand drilled wells were investigated for their natural radioactivity. The determinations of 238U, 234U, 226Ra and 222Rn from 310 samples showed a high state of radioactive disequilibrium between the members of the uranium series present in water. The 238U/226Ra activity ratio usually fell in the range 1 to 20 and the 238U/222Rn activity ratio in the range 1 to 20 x 10-4, the highest activity ratios being from samples with an elevated uranium content. The 234U/238U activity ratio varied between 0.76 and 4.67, the most frequent values showing a 60% excess of 234U in the samples. Most of the 234U/238U activity ratios near unity were found in samples with a high uranium content. Several drilled wells with anomalously high uranium contents were found in southern Finland. The average 226Ra and 222Rn contents of these wells were not exceptionally high, which suggests high mobility of uranium in groundwater from the areas involved. (author)

  10. sup(234) Th scavenging and particle export fluxes from the upper 100 m of the Arabian Sea

    Sarin, M.M.; Rengarajan, R.; Ramaswamy, V.

    (238) U allows us to compute the vertical export flux of particulate sup(234) Th. The flux data for the upper 100 m show spatial variations with enhanced export fluxes centered around 22 degrees N 67 degrees E, a region characterized by higher rates...

  11. 230Th-234U Age-Dating Uranium by Mass Spectrometry

    Williams, R W; Gaffney, A M

    2012-04-18

    This is the standard operating procedure used by the Isotope Ratio Mass Spectrometry Group of the Chemical Sciences Division at LLNL for the preparation of a sample of uranium oxide or uranium metal for {sup 230}Th-{sup 234}U age-dating. The method described here includes the dissolution of a sample of uranium oxide or uranium metal, preparation of a secondary dilution, spiking of separate aliquots for uranium and thorium isotope dilution measurements, and purification of uranium and thorium aliquots for mass spectrometry. This SOP may be applied to uranium samples of unknown purity as in a nuclear forensic investigation, and also to well-characterized samples such as, for example, U{sub 3}O{sub 8} and U-metal certified reference materials. The sample of uranium is transferred to a quartz or PFA vial, concentrated nitric acid is added and the sample is heated on a hotplate at approximately 100 C for several hours until it dissolves. The sample solution is diluted with water to make the solution approximately 4 M HNO{sub 3} and hydrofluoric acid is added to make it 0.05 M HF. A secondary dilution of the primary uranium solution is prepared. Separate aliquots for uranium and thorium isotope dilution measurements are taken and spiked with {sup 233}U and {sup 229}Th, respectively. The spiked aliquot for uranium isotope dilution analysis is purified using EiChrom UTEVA resin. The spiked aliquot for thorium isotope dilution analysis is purified by, first, a 1.8 mL AG1x8 resin bed in 9 M HCl on which U adsorbs and Th passes through; second, adsorbing Th on a 1 mL AG1x8 resin bed in 8 M HNO{sub 3} and then eluting it with 9 M HCl followed by 0.1 M HCl + 0.005 M HF; and third, by passing the Th through a final 1.0 mL AG1x8 resin bed in 9 M HCl. The mass spectrometry is performed using the procedure 'Th and U Mass Spectrometry for {sup 230}Th-{sup 234}U Age Dating'.

  12. Fragment Characteristics from Photofission of 234U and 238U Induced by 6.0 - 9.0 Mev Bremsstrahlung

    Göök, A.; Barday, R.; Chernykh, M.; Eckardt, C.; Enders, J.; Neumann-Cosel, P. Von; Poltoratska, Y.; Wagner, M.; Richter, A.; Oberstedt, S.; Hambsch, F.-J.; Oberstedt, A.

    2011-10-01

    As a preparatory experiment for a search for parity violation in photofission, fission of 238U and 234U induced by 6 - 9 MeV bremsstrahlung has been investigated at the superconducting Darmstadt electron linear accelerator S-DALINAC. Using a twin Frisch grid ionization chamber fission fragment energy and mass distributions have been determined by means of the double kinetic energy technique. The experiment was performed in order to test the ionization chamber's performance in a bremsstrahlung environment. Results on the fission fragment characteristics from the 238U(γ,f) reaction are found to be in good agreement with literature values. In addition results on fission fragment mass and energy distributions from the 234U(γ,f) reaction are presented for the first time in this energy region.

  13. Study of some modern carbonated marine organisms, using U234/U238 activities and its uranium concentration

    Several types of alive carbonated organisms of marine fluvial or mixed environment origin were analized in its concentrations of Uranium and about its activity ratio U234/U238. In the same way measurements were made from the water of these three types of environments. The results indicate that the mollusks shells show a very low concentration compared with corals. Its concentration varies from 0.04 to 0.33 ppm. Inside the limit of errors we can say that the several types of carbonated organisms show the same disequilibrium U234/U238 which was found in associated waters. An analysis of a piece of wood from long time immersed in the sea water was made. The result indicates that there was a marked high in concentration of Uranium due to chelatation with organic matter. (C.D.G.)

  14. Determination of Photofission Fragment Characteristics of 234,238U and 232Th in the Barrier Region

    GÖÖK Alf

    2012-01-01

    The photofission of 232Th, 234U and 238U at excitation energies in the barrier region has been studied. The goal has been to extract information on the mass, total kinetic energy (TKE) and angular distributions of the fission fragments. The experiments were performed using bremsstrahlung, produced by an electron beam in a copper radiator at the injector of the Superconducting Darmstadt linear accelerator (S-DALINAC). Mass and TKE distributions were determined by means of the double kinet...

  15. Defense In-Depth Accident Analysis Evaluation of Tritium Facility Bldgs. 232-H, 233-H, and 234-H

    'The primary purpose of this report is to document a Defense-in-Depth (DID) accident analysis evaluation for Department of Energy (DOE) Savannah River Site (SRS) Tritium Facility Buildings 232-H, 233-H, and 234-H. The purpose of a DID evaluation is to provide a more realistic view of facility radiological risks to the offsite public than the bounding deterministic analysis documented in the Safety Analysis Report, which credits only Safety Class items in the offsite dose evaluation.'

  16. Rapid separation of thorium-234 from uranyl nitrate hexahydrate by adsorption on filter paper from ether solution

    A simple method was developed for the rapid separation of 234Th (UX1) from uranyl nitrate hexahydrate. The method is based on selective dissolution of uranyl nitrate by diethyl ether on a filter paper. It is shown that almost all UX1 is adsorbed by the filter paper which can be desorbed and brought into solution by 5N HCl or HNO3. The effect of different parameters on the separation was also investigated. (author)

  17. Sulphation of Rhizobium sp. NGR234 Nod factors is dependent on noeE, a new host-specificity gene.

    Hanin, M; Jabbouri, S; Quesada-Vincens, D; Freiberg, C; Perret, X; Promé, J C; Broughton, W J; Fellay, R

    1997-06-01

    Rhizobia secrete specific lipo-chitooligosaccharide signals (LCOs) called Nod factors that are required for infection and nodulation of legumes. In Rhizobium sp. NGR234, the reducing N-acetyl-D-glucosamine of LCOs is substituted at C6 with 2-O-methyl-L-fucose which can be acetylated or sulphated. We identified a flavonoid-inducible locus on the symbiotic plasmid pNGR234a that contains a new nodulation gene, noeE, which is required for the sulphation of NGR234 Nod factors (NodNGR). noeE was identified by conjugation into the closely related Rhizobium fredii strain USDA257, which produces fucosylated but non-sulphated Nod factors (NodUSDA). R. fredii transconjugants producing sulphated LCOs acquire the capacity to nodulate Calopogonium caeruleum. Furthermore, mutation of noeE (NGRdelta noeE) abolishes the production of sulphated LCOs and prevents nodulation of Pachyrhizus tuberosus. The sulphotransferase activity linked to NoeE is specific for fucose. In contrast, the sulphotransferase NodH of Rhizobium meliloti seems to be less specific than NoeE, because its introduction into NGRdelta noeE leads to the production of a mixture of LCOs that are sulphated on C6 of the reducing terminus and sulphated on the 2-O-methylfucose residue. Together, these findings show that noeE is a host-specificity gene which probably encodes a fucose-specific sulphotransferase. PMID:9218762

  18. Uranium separation by solvent extraction and determination of 234U/238U isotopic ratios using liquid scintillation spectrometry

    Liquid Scintillation Spectrometer (LSS) coupled with Pulse Shape Analysis has proved to be useful tool for determination of alpha emitting radionuclide, providing high counting efficiency, low background but only moderate energy resolution. Application of solvent extraction significantly reduces the extensive chemical separation needed for alpha spectroscopy technique using surface barrier detectors which allows many simple and effective nuclide separations as a part of sample preparation. LSS provides a nearly total rejection of β-γ emissions by means of pulse shape discrimination combined with counting efficiency higher than 99%. Liquid scintillation coupled with solvent extraction is a reliable, specific, very attractive and quick technique for the determination of U. In the present study, radiochemical separation method was used for the analysis of total uranium concentration as well as determination of 234U/238U isotopic ratios in standard U-ores by LSS. Measurements were carried out using Ultra Low Level LKB Wallac Quantulus 1220 LSS which has built-in Pulse Shape Discriminator and external standard 152Eu which allows the measurement of External Quench Parameter (SQP(E)). For determination of Uranium content in the ores, the direct extraction method by extractive cocktail was used. Liquid scintillation technique was successfully tested on the standard ores with total digestion of the samples to assess the possibility of faster analysis. Results was achieved as an effect of total digestion of the ores followed by extraction of Uranium by Toluene scintillator. Peak fitting procedure available in spectroscopy software was utilized for resolving the α peaks due to 4.17 MeV and 4.77MeV of 238U and 234U. It is seen that the 238U and 234U peaks are well resolved, allowing assessment of their ratio. The Uranium activity determined in the reference U ores is exemplified. The activity concentrations and isotopic Uranium activity ratios derived from LSS indicates

  19. Corrective Action Investigation Plan for Corrective Action Unit 234: Mud Pits, Cellars, and Mud Spills, Nevada Test Site, Nevada, Revision 0

    Corrective Action Unit 234, Mud Pits, Cellars, and Mud Spills, consists of 12 inactive sites located in the north and northeast section of the NTS. The 12 CAU 234 sites consist of mud pits, mud spills, mud sumps, and an open post-test cellar. The CAU 234 sites were all used to support nuclear testing conducted in the Yucca Flat and Rainier Mesa areas during the 1950s through the 1970s. The CASs in CAU 234 are being investigated because hazardous and/or radioactive constituents may be present in concentrations that could potentially pose a threat to human health and the environment. Existing information on the nature and extent of potential contamination is insufficient to evaluate and recommend corrective action alternatives for the CASs. Additional information will be generated by conducting a CAI before evaluating and selecting appropriate corrective action alternatives

  20. Redundant 230Th/ 234U/ 238U, 231Pa/ 235U and 14C dating of fossil corals for accurate radiocarbon age calibration

    Chiu, Tzu-Chien; Fairbanks, Richard G.; Mortlock, Richard A.; Cao, Li; Fairbanks, Todd W.; Bloom, Arthur L.

    2006-09-01

    230Th/ 234U/ 238U dating of fossil corals by mass spectrometry is remarkably precise, but some samples exposed to freshwater over thousands of years may gain and/or lose uranium and/or thorium and consequently yield inaccurate ages. Although a δ 234U initial value equivalent to modern seawater and modern corals has been an effective quality control criterion, for samples exposed to freshwater but having δ 234U initial values indistinguishable from modern seawater and modern corals, there remains a need for additional age validation in the most demanding applications such as the 14C calibration (Fairbanks et al., 2005. Radiocarbon calibration curve spanning 0 to 50,000 years BP based on paired 230Th/ 234U/ 238U and 14C dates on pristine corals. Quaternary Science Reviews 24(16-17), 1781-1796). In this paper we enhance screening criteria for fossil corals older than 30,000 years BP in the Fairbanks0805 radiocarbon calibration data set (Fairbanks et al., 2005) by measuring redundant 230Th/ 234U/ 238U and 231Pa/ 235U dates via multi-collector magnetic sector inductively coupled plasma mass spectrometry (MC-MS-ICPMS) using techniques described in Mortlock et al. (2005. 230Th/ 234U/ 238U and 231Pa/ 235U ages from a single fossil coral fragment by multi-collector magnetic-sector inductively coupled plasma mass spectrometry. Geochimica et Cosmochimica Acta 69(3), 649-657.). In our present study, we regard paired 231Pa/ 235U and 230Th/ 234U/ 238U ages concordant when the 231Pa/ 235U age (±2 σ) overlaps with the associated 230Th/ 234U/ 238U age (±2 σ). Out of a representative set of 11 Fairbanks0805 (Fairbanks et al., 2005) radiocarbon calibration coral samples re-measured in this study, nine passed this rigorous check on the accuracy of their 230Th/ 234U/ 238U ages. The concordancy observed between 230Th/ 234U/ 238U and 231Pa/ 235U dates provides convincing evidence to support closed system behavior of these fossil corals and validation of their 230Th/ 234U/ 238U

  1. 234Th, 210Pb, 210Po and stable Pb in the central equatorial Pacific: Tracers for particle cycling

    Murray, J.W.; Paul, B.; Dunne, J.P.; Chapin, T.

    2005-01-01

    Samples were collected during the 1992 US JGOFS EqPac Survey I and II cruises from 12??N to 12??S at 140??W in the central equatorial Pacific for water column profiles of dissolved, particulate and total 234Th, 210Pb and 210Po and total acid soluble stable Pb and sediment trap fluxes of 234Th, 210Pb and 210Po. Survey I occurred in February/March with moderate El Nino conditions while Survey II was conducted in September/October when there was a well developed cold-tongue. 234Th, 210Pb and 210Po are all particle reactive yet they partition differently between dissolved and particulate phases. Fractionation factors (the ratios of the distribution coefficients) show that the selectivity for suspended and sediment trap particles follows Th>Po>Pb. Scavenging residence times (??) for 234Th, 210Pb and 210Po ranged from 25 to 100 d, 3 to 8 years and 100 to 500 d, respectively. These particle reactive tracers have very different distributions in the water column, which reflect differences in their sources and sinks. The deficiency of 234Th relative to 238U was fairly uniformly distributed meridionally, though deficiencies were higher during Survey II when there was higher new production. Excess 210Pb relative to 226Ra was very asymmetrical with much higher excess values north of the equator. The distributions were similar for Surveys I and II. The deficiency of 210Po relative to 210Pb had a symmetrical distribution about the equator for both Survey I and II but the deficiencies were larger during Survey I when upwelling was smaller. Stable Pb was generally higher at the surface than at 250 m and there was no meridional trend from 12??N to 12??S. A mass balance for 210Pb was used to determine the atmospheric input of 210Pb. The average values for Surveys I and II were 0.12 and 0.32 dpm cm-2 year-1, respectively. There was no general increase in atmospheric input of 210Pb north of the equator but there was a strong maximum at 2-3??N during Survey I coincident with the

  2. Structure of the Cellulose Synthase Complex of Gluconacetobacter hansenii at 23.4 Å Resolution.

    Du, Juan; Vepachedu, Venkata; Cho, Sung Hyun; Kumar, Manish; Nixon, B Tracy

    2016-01-01

    Bacterial crystalline cellulose is used in biomedical and industrial applications, but the molecular mechanisms of synthesis are unclear. Unlike most bacteria, which make non-crystalline cellulose, Gluconacetobacter hansenii extrudes profuse amounts of crystalline cellulose. Its cellulose synthase (AcsA) exists as a complex with accessory protein AcsB, forming a 'terminal complex' (TC) that has been visualized by freeze-fracture TEM at the base of ribbons of crystalline cellulose. The catalytic AcsAB complex is embedded in the cytoplasmic membrane. The C-terminal portion of AcsC is predicted to form a translocation channel in the outer membrane, with the rest of AcsC possibly interacting with AcsD in the periplasm. It is thus believed that synthesis from an organized array of TCs coordinated with extrusion by AcsC and AcsD enable this bacterium to make crystalline cellulose. The only structural data that exist for this system are the above mentioned freeze-fracture TEM images, fluorescence microscopy images revealing that TCs align in a row, a crystal structure of AcsD bound to cellopentaose, and a crystal structure of PilZ domain of AcsA. Here we advance our understanding of the structural basis for crystalline cellulose production by bacterial cellulose synthase by determining a negative stain structure resolved to 23.4 Å for highly purified AcsAB complex that catalyzed incorporation of UDP-glucose into β-1,4-glucan chains, and responded to the presence of allosteric activator cyclic diguanylate. Although the AcsAB complex was functional in vitro, the synthesized cellulose was not visible in TEM. The negative stain structure revealed that AcsAB is very similar to that of the BcsAB synthase of Rhodobacter sphaeroides, a non-crystalline cellulose producing bacterium. The results indicate that the crystalline cellulose producing and non-crystalline cellulose producing bacteria share conserved catalytic and membrane translocation components, and support the

  3. Structure of the Cellulose Synthase Complex of Gluconacetobacter hansenii at 23.4 A Resolution.

    Juan Du

    Full Text Available Bacterial crystalline cellulose is used in biomedical and industrial applications, but the molecular mechanisms of synthesis are unclear. Unlike most bacteria, which make non-crystalline cellulose, Gluconacetobacter hansenii extrudes profuse amounts of crystalline cellulose. Its cellulose synthase (AcsA exists as a complex with accessory protein AcsB, forming a 'terminal complex' (TC that has been visualized by freeze-fracture TEM at the base of ribbons of crystalline cellulose. The catalytic AcsAB complex is embedded in the cytoplasmic membrane. The C-terminal portion of AcsC is predicted to form a translocation channel in the outer membrane, with the rest of AcsC possibly interacting with AcsD in the periplasm. It is thus believed that synthesis from an organized array of TCs coordinated with extrusion by AcsC and AcsD enable this bacterium to make crystalline cellulose. The only structural data that exist for this system are the above mentioned freeze-fracture TEM images, fluorescence microscopy images revealing that TCs align in a row, a crystal structure of AcsD bound to cellopentaose, and a crystal structure of PilZ domain of AcsA. Here we advance our understanding of the structural basis for crystalline cellulose production by bacterial cellulose synthase by determining a negative stain structure resolved to 23.4 Å for highly purified AcsAB complex that catalyzed incorporation of UDP-glucose into β-1,4-glucan chains, and responded to the presence of allosteric activator cyclic diguanylate. Although the AcsAB complex was functional in vitro, the synthesized cellulose was not visible in TEM. The negative stain structure revealed that AcsAB is very similar to that of the BcsAB synthase of Rhodobacter sphaeroides, a non-crystalline cellulose producing bacterium. The results indicate that the crystalline cellulose producing and non-crystalline cellulose producing bacteria share conserved catalytic and membrane translocation components, and

  4. Retrospective review of 234 scaphoid fractures and nonunions treated with arthroscopy for union and complications.

    Slade, J F; Gillon, T

    2008-01-01

    The purpose of this paper is to retrospectively review 234 consecutive cases of scaphoid fractures and nonunions treated using arthroscopy with the dorsal percutaneous implantation of a headless compression screw for healing and complications. Solid union of fracture is determined by CT scan. We identified 126 acute injuries, including 65 proximal pole fractures; 67 grossly displaced fractures; 12 trans-scaphoid perilunate dislocations including four trans-scaphoid trans-capitate fractures; and ten combined scaphoid and distal radius fractures. 108 scaphoid nonunions were identified. 98 were correctly aligned and ten had a humpback deformity which was correctable using arthroscopic assisted reduction techniques at the time of surgery. 82 presented with a fracture gap 2mm or greater requiring percutaneous bone grafting. 12 cases of avascular necrosis (AVN) were identified by MRI. 20 nonunions had surgery performed at other institutions. The mean time to surgery for the nonunions was 20 months. 99% union rate of acute scaphoid fractures was obtained by 12 weeks, as determined by CT scan. Two complications were identified (3%). One case of delayed healing was identified. this delayed union was treated with percutaneous bone grafting and continued on to heal uneventfully. The other complication was a case of volar trans-scaphoid peri-lunate dislocation. While the fracture healed, the patient developed a traumatic dislocation requiring a capitate-lunate arthrodesis. Treatment of scaphoid nonunions resulted in ten cases of delayed healing, which were treated with repeat percutaneous bone grafting. This represented a 9% complication rate. of the ten cases of delayed unions that were re-bone grafted, four failed to heal by nine months. This resulted in a 96% union rate of our nonunion group by nine months. when acute fracture healing was compared to nonunions the average healing of acute fractures as determined by CT scanning measuring trabecular bridging was 12 weeks

  5. Measurement of the U-234(n,f) cross section with PPAC detectors at the nTOF facility

    The aim of this work was twofold: to measure the 234U neutron-induced fission cross section in an extended energy range with an unprecedented resolution, and, in the process, to validate the experimental method we used at the new n-TOF-CERN facility. The experiment was designed in order to take advantage of the unique characteristics of the n-TOF facility: the long flight path offers a high energy resolution and the high-intensity, instantaneous neutron flux greatly reduces the background from the sample activities, making it possible to measure highly radioactive samples. The fission detection setup is based on an innovative technique that benefits from the use of very thin targets and detectors. Up to nine targets of high purity fission samples are sandwiched by Parallel Plate Avalanche Counters (PPAC). When a fission event happens, the two complementary fission fragments are detected by the PPACs adjacent to the fissioning target in a narrow time coincidence. Because several targets are simultaneously placed in-beam, relative measurements with respect to reference nuclei can be obtained. In this work, an original data-reduction method has been developed to deal with the particular characteristics of both the n-TOF data acquisition system, which is based on very accurate Flash-ADC digitizers, and the fission detection setup. The data reduction includes the coincidence windows and the signal amplitude requirements that we obtained from preliminary data analysis. The applied coincidence method is very powerful for dealing with the background rejection such as contamination by α activity, which is quite high for 234U, and the signals produced by highly energetic reactions in the detectors. The data-reduction method also implements the fission event reconstruction using the position information obtained from the stripped cathodes and the delay line readout, which makes it possible to determine the fission fragment angular distributions, and the time-of-flight to

  6. 234例胃癌淋巴结转移与病理特征的关系

    吴丽华; 尚士光; 封丽; 姜殿君

    2012-01-01

    Objective to explore the gastric cancer (EGC) state of lymph node metastasis and pathological characteristics of the correlation. Methods 234 cases of patients with gastric cancer pathological material to carry on the analysis, analysis of the state of lymph node metastasis and pathological characteristics of the correlation. Results 234 cases of patients with 36 cases of EGC have lymph node metastasis, the metastasis rate 15.39%. EGC lymph node metastasis and tumor diameter, gross type, histology, infiltration depth, lymphatic invasion is closely related to the (P < 0.05 or P < 0.01), and the patients age, sex, tumor site, lesions number, pathological types have nothing to do. Conclusion sure stomach cancer surgery scheme, may refer to tumor size, tumor differentiation degree, infiltration depth, lymphatic cancer bolt factors such as the judge lymph node metastasis risk, to decide whether to do lymph node dissections.%目的探讨胃癌(EGC)的淋巴结转移状态与病理特征的相关性.方法对234例胃癌患者病理资料进行分析,分析淋巴结转移状态与病理特征的相关性.结果234例EGC患者中36例有淋巴结转移,转移率15.39%.EGC淋巴结转移与肿瘤直径、大体类型、组织学类型、浸润深度、淋巴管侵犯密切相关(P<0.05或P<0.01),与患者年龄、性别、肿瘤部位、病灶数、病理类型无关.结论确定胃癌手术方案时,可参考肿瘤大小、肿瘤分化程度、浸润深度、淋巴管癌栓等因素判断淋巴结转移风险,决定是否行淋巴结清扫术.

  7. Study of the $^{234}$U(n,f) fission fragment angular distribution at the CERN n_TOF facility

    Cidoncha-Leal, E; Paradela, C; Tarrío, D; Leong, L S; Audouin, L; Tassan-Got, L; Altstadt, S; Andrzejewski, J; Barbagallo, M; Bécares, V; Becvár, F; Belloni, F; Berthoumieux, E; Billowes, J; Boccone, V; Bosnar, D; Brugger, M; Calviani, M; Calviño, F; Cano-Ott, D; Carrapiço, C; Cerutti, F; Chiaveri, E; Chin, M; Colonna, N; Cortés, G; Cortés-Giraldo, M A; Diakaki, M; Domingo-Pardo, C; Dressler, R; Dzysiuk, N; Eleftheriadis, C; Ferrari, A; Fraval, K; Ganesan, S; García, A R; Giubrone, G; Gómez-Hornillos, M B; Gonçalves, I F; González-Romero, E; Griesmayer, E; Guerrero, C; Gunsing, F; Gurusamy, P; Hernández-Prieto, A; Jenkins, D G; Jericha, E; Kadi, Y; Käppeler, F; Karadimos, D; Kivel, N; Koehler, P; Kokkoris, M; Krticka, M; Kroll, J; Lampoudis, C; Langer, C; Lederer, C; Leeb, H; Losito, R; Mallick, A; Manousos, A; Marganiec, J; Martínez, T; Massimi, C; Mastinu, P F; Mastromarco, M; Meaze, M; Mendoza, E; Mengoni, A; Milazzo, P M; Mingrone, F; Mirea, M; Mondalaers, W; Pavlik, A; Perkowski, J; Plompen, A; Praena, J; Quesada, J M; Rauscher, T; Reifarth, R; Riego, A; Robles, M S; Roman, F; Rubbia, C; Sabaté-Gilarte, M; Sarmento, R; Saxena, A; Schillebeeckx, P; Schmidt, S; Schumann, D; Tagliente, G; Tain, J L; Tsinganis, A; Valenta, S; Vannini, G; Variale, V; Vaz, P; Ventura, A; Versaci, R; Vermeulen, M J; Vlachoudis, V; Vlastou, R; Wallner, A; Ware, T; Weigand, M; Weiß, C; Wright, T; Zugec, P

    2014-01-01

    The angular distribution of the f ssion fragments (FFAD) produced in neutron- induced reactions of actinides have been measured with a f ssion detection setup based on parallel-plate avalanche counters (PPACs) at the Neutron Time- Of-Flight (n_TOF) facility at CERN. The main features of the setup and pre- liminary results are reported here forthe 234 U(n,f)reaction measurement show- ing a high concordance with previous data, while providing new results up to 100 MeV.

  8. Determination of photofission fragment characteristics of {sup 234,238}U and {sup 232}Th in the barrier region

    Goeoek, Alf

    2012-11-05

    The photofission of {sup 232}Th, {sup 234}U and {sup 238}U at excitation energies in the barrier region has been studied. The goal has been to extract information on the mass, total kinetic energy (TKE) and angular distributions of the fission fragments. The experiments were performed using bremsstrahlung, produced by an electron beam in a copper radiator at the injector of the Superconducting Darmstadt linear accelerator (S-DALINAC). Mass and TKE distributions were determined by means of the double kinetic energy technique using a twin Frisch grid ionization chamber. The angular distributions were derived simultaneously by measuring the drift time of ionization electrons. Results show that this drift-time method is comparable in accuracy to other more commonly used methods, but with a simplified procedure for setting up the experiment. Mass, TKE and angular distributions have been obtained from bremsstrahlung-induced fission of {sup 232}Th at average excitation energies left angle E{sub x} right angle =6.68 MeV and 7.26 MeV, for {sup 234}U at left angle E{sub x} right angle =5.80 MeV, 6.49 MeV and 7.23 MeV, and for {sup 238}U at left angle E{sub x} right angle =5.90 MeV, 6.11 MeV and 6.93 MeV. Results on fission fragment characteristics from {sup 238}U({gamma},f) show good agreement with literature data, which verifies the experimental procedure. The correlated mass and TKE data have been analyzed in terms of fission modes within the multi-modal random-neck-rupture model. The result exhibits a dominant yield of the mass asymmetric standard-2 mode in all the investigated fissioning nuclei, with a relative yield of {proportional_to}77 % in {sup 232}Th, {proportional_to}75 % in {sup 234}U and {proportional_to}67 % in {sup 238}U. No strong fluctuation of the mode yields were found as a function of the excitation energy. Correlations between mass, TKE and angular distributions have been investigated in {sup 232}Th and {sup 234}U. The correlation takes the form of an

  9. The most compact scission configuration of fragments from low energy fission of 234U and 236U

    Using a time of flight technique, the maximal values of the kinetic energy as a function of the primary mass of fragments from low energy fission of 234U and 236U were measured by Signarbieux et al. From calculations of scission configurations, one can conclude that, for those two fissioning systems, the maximal values of the total kinetic energy corresponding to fragmentations (42Mo62, 50Sn80) and (42Mo64, 50Sn80) respectively, are equal to the available energy, and that their scission configurations are composed of a spherical heavy fragment and a prolate light fragment, both in their ground state. (author).

  10. Priority rankings of the system modifications to reduce core damage frequency of Wolsong NPP units 2/3/4

    The analysis for priority rankings of the recommendations to reduce the total core damage frequency (CDF) of Wolsong nuclear power plant units 2/3/4 was performed in this paper. In order to derive the recommendations, the sensitivity analysis of CDF on which major contributors effect was performed based on the accident quantification results during Level 1 probabilistic safety assessments (PSA). Priorities were ranked in the way that compares the CDF reduction rate with the efforts required to implement those recommendations using risk matrix

  11. Absolute L X-ray intensities in the decays of 230Th, 234U, 238Pu and 244Cm

    The absolute L X-ray emission rates of 230Th, 234U, 238Pu and 244Cm have been measured. The rates were obtained by an alpha-particle gated photon spectrometry technique involving the use of a highly calibrated Ge(HP) detector in coincidence with a SiSB detector. The directional correlation between L X-rays and alpha-particles has been accounted for. The present results are compared with previous experimental values and theoretical estimates. Agreement with theoretical estimates is good, however few of the previous experimental values agree with the present work. Differences with previous work partly seem to lie with the detector calibration. (orig.)

  12. Coupled 230Th/234U-ESR analyses for corals: A new method to assess sealevel change

    Although coupled 230Th/234U-ESR analyses have become routine for dating teeth, they have never been used for corals. While the ESR age depends on, and requires assumptions about, the time-averaged cosmic dose rate, D-barcos(t), 230Th/234U dates do not. Since D-barcos(t) received by corals depends on the attenuation by any intervening material, D-barcos(t) response reflects changing water depths and sediment cover. By coupling the two methods, one can determine the age and a unique D-barcos,coupled(t) simultaneously. From a coral's water depth and sedimentary history as predicted by a given sealevel curve, one can predict D-barcos,sealevel(t). If D-barcos,coupled(t) agrees well with D-barcos,sealevel(t), this provides independent validation for the curve used to build D-barcos,sealevel(t). For six corals dated at 7-128 ka from Florida Platform reef crests, the sealevel curve by Waelbroeck et al. [2002. Sea-level and deep water temperature changes derived from benthonic foraminifera isotopic records. Quat. Sci. Rev. 21, 295-305] predicted their D-barcos,coupled(t) values as well as, or better than, the SPECMAP sealevel curve. Where a whole reef can be sampled over a transect, a precise test for sealevel curves could be developed

  13. IGRINS Near-IR High-Resolution Spectroscopy of Multiple Jets around LkH$\\alpha$ 234

    Oh, Heeyoung; Yuk, In-Soo; Park, Byeong-Gon; Park, Chan; Chun, Moo-Young; Pak, Soojong; Kim, Kang-Min; Oh, Jae Sok; Jeong, Ueejeong; Yu, Young Sam; Lee, Jae-Joon; Kim, Hwihyun; Hwang, Narae; Kaplan, Kyle; Pavel, Michael; Mace, Gregory; Lee, Hye-In; Le, Huynh Anh Nguyen; Lee, Sungho; Jaffe, Daniel T

    2016-01-01

    We present the results of high-resolution near-IR spectroscopy toward the multiple outflows around the Herbig Be star Lk{\\Ha} 234 using the Immersion Grating Infrared Spectrograph (IGRINS). Previous studies indicate that the region around Lk{\\Ha} 234 is complex, with several embedded YSOs and the outflows associated with them. In simultaneous H$-$ and K$-$band spectra from HH 167, we detected 5 {\\FeII} and 14 H$_{2}$ emission lines. We revealed a new {\\FeII} jet driven by radio continuum source VLA 3B. Position-velocity diagrams of H$_{2}$ 1$-$0 S(1) $\\lambda$2.122 $\\micron$ line show multiple velocity peaks. The kinematics may be explained by a geometrical bow shock model. We detected a component of H$_{2}$ emission at the systemic velocity (V$_{LSR}$ $=$ $-$10.2 {\\kms}) along the whole slit in all slit positions, which may arise from the ambient photodissociation region. Low-velocity gas dominates the molecular hydrogen emission from knots A and B in HH 167, which is close to the systemic velocity, {\\FeII} ...

  14. 230Th/234U dating of the quaternary spring travertines in the Arava Rift Valley of Israel and paleoclimatic implications

    Springs and lake deposits (travertines) sampled along the western margins of the Arava segment of the Dead Sea Rift Valley, Israel, were studied as a potential source of palaeoclimatic information. The 230Th/234U disequilibrium method was used to determine the age of the investigated deposits. The radiometric dating was supplemented by detailed petrographic and chemical analyses of the collected samples. Detailed petrographic observations of the analysed travertine samples suggest their deposition under moderately-arid conditions, alternating with arid to extremely arid periods. This evidence is consistent with the preliminary conclusions drawn from palynological studies in the area. Dating by the 230Th/234U disequilibrium method indicates that most travertine ages correspond to oceanic 18O stages 5 and 7. The good correspondence between apparent ages as deduced from the position of the travertines in vertical and lateral successions and the radiometric ages, lends credibility to the radiometric ages. The clustering of ages during the warm 18O stages bears similarity to the temporal distribution of middle to late Pleistocene sapropelic horizons in the Eastern Mediterranean Basin which further leads to suspicion that during insolation maxima monsoonal cells originating in the Indian Ocean have shifted northwards reaching the latitude of the Arava and Negev Highlands. Refs and figs

  15. Alpha Spectrometry for Determination of 238U, 235U, 234U, 232Th and 230Th in Soil Sample

    Monitoring of radioactivity in soil around the nuclear power plant is important. In this study, the radioactivity of uranium and thorium isotopes in soil (NIST SRM 2709a) is analyzed by alpha spectrometry. Alpha spectrometry is a powerful analytical tool for the identification and assay of the alpha-emitting sources primarily due to its high counting efficiency, high sensitivity and low price. Another aim of this study is to present the extent of disequilibrium of 238U/234U and 238U/230Th. The soil sample was decomposed by a fusion technique, and the source for the alpha spectrometry was prepared by electrodeposition of an alpha-emitting nuclides onto a metallic substrate. In this work, uranium and thorium isotopes were chemically separated from a soil sample (NIST SRM 2709a) using chromatographic columns, and electrodeposited on a stainless steel disc to measure the radioactivity concentration of the isotopes with an alpha spectrometer. The ratio of 238U/234U for the soil sample was ca. 1 which is considered to be in secular equilibrium

  16. Evidence of Planetesimal infall on to the very young Herbig Be star LkH$_\\alpha$234

    Chakraborty, A; Mahadevan, S

    2004-01-01

    We report here the first evidence for planetesimal infall onto the very young Herbig Be star LkH$_\\alpha$234. These results are based on observations acquired over 31 days using spectroscopy of the sodium D lines, the He I 5876\\AA, and hydrogen H$_\\alpha$ lines. We find Redshifted Absorption Components (RAC) with velocities up to 200 km/s and very mild Blueshifted Absorption Components (BEC) up to 100 km/s in the Na I lines. No correlation is observed between the appearance of the Na I RAC & BEC and the H$_\\alpha$ and He I line variability, which suggests that these (Na I RAC & BEC) are formed in a process unrelated to the circumstellar gas accretion. We interpret the Na I RAC as evidence for an infalling evaporating body, greater than 100 km in diameter, which is able to survive at distances between 2.0 to 0.1 AU from the star. The dramatic appearance of the sodium RAC and mild BEC is readily explained by the dynamics of this infalling body making LkH$_\\alpha$234 the youngest (age $\\sim$ 0.1 Myr) sys...

  17. 2,3,4-Trihydroxybenzyl-hydrazide analogues as novel potent coxsackievirus B3 3C protease inhibitors.

    Kim, Bo-Kyoung; Ko, Hyojin; Jeon, Eun-Seok; Ju, Eun-Seon; Jeong, Lak Shin; Kim, Yong-Chul

    2016-09-14

    Human coxsackievirus B3 (CVB3) 3C protease plays an essential role in the viral replication of CVB3, which is a non-enveloped and positive single-stranded RNA virus belonging to Picornaviridae family, causing acute viral myocarditis mainly in children. During optimization based on SAR studies of benserazide (3), which was reported as a novel anti-CVB3 3C(pro) agent from a screening of compound libraries, the 2,3,4-trihydroxybenzyl moiety of 3 was identified as a key pharmacophore for inhibitory activity against CVB3 3C(pro). Further optimization was performed by the introduction of various aryl-alkyl substituted hydrazide moieties instead of the serine moiety of 3. Among the optimized compounds, 11Q, a 4-hydroxyphenylpentanehydrazide derivative, showed the most potent inhibitory activity (IC50 = 0.07 μM). Enzyme kinetics studies indicated that 11Q exhibited a mixed inhibitory mechanism of action. The antiviral activity against CVB3 was confirmed using the further derived analogue (14b) with more cell permeable valeryl ester group at the 2,3,4-trihydroxy moiety. PMID:27191615

  18. Origin and geochemical behavior of uranium in marine sediments. Utilization of the 234U/238U ratio in marine geochemistry

    The first part of this thesis presents the current situation of knowledge of uranium in marine environment. The second part describes the methods of analysis as well as the material support of the study, i.e., the sediments and marine deposits investigated. The third part is dedicated to the study of uranium mobility in marine sediments characterized by detrital terrigenous composition (pelagic clays). This approach allowed quantifying the entering and leaving flux of uranium after the sediment settling and, to discuss, on this basis, the consequences on the uranium oceanic balance. In the third part the origin and behavior of uranium in zones of high surface productivity is studied. The uranium enrichments observed in the hemi-pelagic sediments of the EUMELI (J.G.O.F.S.-France) programme will constitute a material of study adequate for measuring the variations in the 234U/238U ratio in solid phase, in response to the oxido-reducing characteristics of the sediment. Thus establishing the origin of the trapped uranium has been possible. Also, the nature of the sedimentary phases related to uranium in bio-genetic sediments in the Austral Ocean was determined. Thus a relationship between the variations in the 234U/238 and the diagenetic transformations was possible to establish. Finally in the fifth part a study of the behavior of uranium in a polymetallic shell characteristic for deposits of hydrogenized origin

  19. Measurements of /sup 234/U, /sup 238/U and /sup 230/Th in excreta of uranium-mill crushermen

    Fisher, D.R.; Jackson, P.O.; Brodacynski, G.G.; Scherpelz, R.I.

    1982-07-01

    Uranium and thorium levels in excreta of uranium mill crushermen who are routinely exposed to airborne uranium ore dust were measured. The purpose was to determine whether /sup 230/Th was preferentially retained over either /sup 234/U or /sup 238/U in the body. Urine and fecal samples were obtained from fourteen active crushermen with long histories of exposure to uranium ore dust, plus four retired crushermen and three control individuals for comparison. Radiochemical procedures were used to separate out the uranium and thorium fractions, which were then electroplated on stainless steel discs and assayed by alpha spectrometry. Significantly greater activity levels of /sup 234/U and /sup 238/U were measured in both urine and fecal samples obtained from uranium mill crushermen, indicating that uranium in the inhaled ore dust was cleared from the body with a shorter biological half-time than the daughter product /sup 230/Th. The measurements also indicated that uranium and thorium separate in vivo and have distinctly different metabolic pathways and transfer rates in the body. The appropriateness of current ICRP retention and clearance parameters for /sup 230/Th in ore dust is questioned.

  20. Seasonal variations of total 234Th and dissolved 238U concentration activities in surface water of Bransfield Strait, Antarctica, from March to October 2011

    In this study the naturally occurring radionuclides 234Th and 238U were used to investigate the magnitude of upper ocean particulate organic carbon export in Bransfield Strait, Southern Ocean. This region is the largest oceanic high-nitrate low-chlorophyll (HNLC) area in the world and is known to contribute to regulate of the atmospheric CO2 via the biological pump. Due to its different geochemical behavior in seawater, the resulting U/Th disequilibria can be easily used to constrain the transport rates of particles and reaction processes between solution and particulate phases. Sampling occurred during the summer (March and November) 2011. Total 234Th activities in surface seawater samples ranged from 1.3 to 3.7 dpm L-1 (station EB 011) during March/11 campaign, while in October/11 total 234Th activity concentrations varied from 1.4 to 2.9 dpm L-1. Highest total 234Th activities were found late in the austral summer season. Activity concentrations of dissolved 238U in surface seawater varied from 2.1 to 2.4 dpm L-1. Taking into account all sampling stations established in March and October/11 the relative variability of total 234Th distribution was 22%. (author)

  1. Seasonal variations of total {sup 234}Th and dissolved {sup 238}U concentration activities in surface water of Bransfield Strait, Antarctica, from March to October 2011

    Lapa, Flavia V.; Oliveira, Joselene de; Costa, Alice M.R., E-mail: fvlapa@ipen.br, E-mail: jolivei@ipen.br, E-mail: lice_mrc@hotmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil). Laboratorio de Radiometria Ambiental; Braga, Elisabete S., E-mail: edsbraga@usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Inst. Oceanografico. Lab. de Nutrientes, Micronutrientes e Tracos nos Oceanos

    2013-07-01

    In this study the naturally occurring radionuclides {sup 234}Th and {sup 238}U were used to investigate the magnitude of upper ocean particulate organic carbon export in Bransfield Strait, Southern Ocean. This region is the largest oceanic high-nitrate low-chlorophyll (HNLC) area in the world and is known to contribute to regulate of the atmospheric CO{sub 2} via the biological pump. Due to its different geochemical behavior in seawater, the resulting U/Th disequilibria can be easily used to constrain the transport rates of particles and reaction processes between solution and particulate phases. Sampling occurred during the summer (March and November) 2011. Total {sup 234}Th activities in surface seawater samples ranged from 1.3 to 3.7 dpm L{sup -1} (station EB 011) during March/11 campaign, while in October/11 total {sup 234}Th activity concentrations varied from 1.4 to 2.9 dpm L{sup -1}. Highest total {sup 234}Th activities were found late in the austral summer season. Activity concentrations of dissolved {sup 238}U in surface seawater varied from 2.1 to 2.4 dpm L{sup -1}. Taking into account all sampling stations established in March and October/11 the relative variability of total {sup 234}Th distribution was 22%. (author)

  2. Fragment characteristics from fission of 238U and 234U induced by 6.5-9.0 MeV bremsstrahlung

    Göök, A.; Chernykh, M.; Eckardt, C.; Enders, J.; von Neumann-Cosel, P.; Oberstedt, A.; Oberstedt, S.; Richter, A.

    2011-02-01

    Fission of 238U and 234U induced by bremsstrahlung of 6.5-9.0 MeV endpoint energy has been investigated at the superconducting Darmstadt electron linear accelerator S-DALINAC. Using a twin Frisch grid ionization chamber, fission-fragment energy and mass distributions have been determined by means of the double kinetic-energy technique. Results on the fission-fragment characteristics from U238(γ,f) are in agreement with results from the literature. In addition fission-fragment mass and energy distributions from U234(γ,f) are presented for the first time in this energy region. An analysis of fission modes within the Brosa model has been performed. The relative yield of the S1 mode was found to be (13±3)% in 234U and (35±2)% in 238U.

  3. Vertical and horizontal particle transport in the coastal waters of a large lake: An assessment by sediment trap and thorium-234 measurements

    Waples, James T.; Klump, J. Val

    2013-10-01

    The horizontal and vertical flux of particulate material in the nearshore of southern Lake Michigan (0-40 m) was estimated with the naturally occurring radionuclide 234Th. Horizontal fluxes of 234Th supplemented apparent vertical fluxes of 234Th in the water column (based on local 234Th/238U disequilibria) by a factor of 7-14, reinforcing the importance of lateral transport in coastal environments. Calculated onshore transport of particulate material across the 40 m isobath was as high as 1.1 × 106 kg km-1 d-1, and exceeds estimates of terrigenous (riverine and bluff erosion) loading. Estimates of onshore flux of organic carbon exceeded areal primary productivity by as much as ˜300%, and should be considered in nearshore carbon budgets. Bottom-tethered sediment traps (placed 5 m above the bottom) measured sedimentation rates that were ˜1 order of magnitude lower than 234Th derived mass fluxes from the water column and ˜2 orders of magnitude lower than 234Th derived mass fluxes to the lakebed. We ascribe this difference to under collecting by the sediment trap either because of trap hydrodynamics or flux occurring below the trap capture plane. Cross-shore fluxes showed a periodicity of ˜4 days and correlated strongly with a topographic vorticity wave that is present throughout the year in southern Lake Michigan. The impact of this wave (as a driver of bidirectional cross-shore flux) on biogeochemical cycling and both nearshore and offshore food webs has not yet been explicitly considered.

  4. Particle-reactive radionuclides (234Th, 210Pb, 210 as tracers for the estimation of export production in the South China Sea

    P. H. Santschi

    2011-12-01

    Full Text Available The time-series station, SEATS (18° N, 116° E in the South China Sea was visited six times during October 2006–December 2008 to carry out seawater sampling and floating trap deployments for the determination of distributions and fluxes of POC, PIC, PN, 234Th, 210Pb, and 210Po in the upper 200 m of the water column. Radionuclide deficiencies resulted in removal fluxes from the euphotic layer of 1.1×103–1.8×103 dpm m−2d−1 and 7.1–40.2 dpm m−2d−1 for 234Th and 210Po, respectively. Due to atmospheric input, an excess of 210Pb relative to 226Ra is commonly observed in the upper water column. Sinking fluxes of total mass, POC, PIC, PN, 234Th, 210Pb, and 210Po measured at the euphotic depth were low in summer-fall and high in winter-spring, reflecting the seasonal variability of biological pumping. Excluding the suspiciously low primary productivity data point in July 2007, a relatively high e-ratio of 0.28–0.69 was estimated by the ratio of the POC flux at the euphotic depth and the integrated primary productivity. The ratios of 234Th, 210Pb, and 210Po to organic carbon, inorganic carbon, and nitrogen in the sinking particles were combined with the disequilibria of 234Th–238U, 210Pb–226Ra, and 210Po–210Pb to estimate export fluxes of POC, PIC, and PN from the euphotic layer. Compared with measured fluxes by the sediment trap and estimated fluxes by other approaches, it is concluded that the export production in the South China Sea, ranging from 1.8 to 21.3 mmol-C m−2d−1, can be reasonably estimated using 234Th, 210Pb, and 210Po as carbon proxies.

  5. The transfer of uranium isotopes 234U and 238U to the waters interacting with carbonates from Mendip Hills area (England)

    Laboratory time-scale experiments were conducted on limestone and dolomite gravels from the Mendip Hills area, England, with the purpose of evaluating the release of 238U and 234U to different aqueous solutions. The 234U/238U activity ratio (AR) lab data were reliable to interpret the field data. The obtained values do not indicate a reduction in the amount of dissolved U and an increase in the AR of the remaining dissolved U as commonly observed for groundwater systems close to redox boundaries

  6. Measurements of the 234U(n,f) Reaction with a Frisch-Grid Ionization Chamber up to En=5 MeV

    Al-Adili, Ali

    2013-01-01

    This study on the neutron-induced fission of 234U was carried out at the 7 MV Van de Graaff accelerator of IRMM in Belgium. A Twin Frisch-Grid Ionization Chamber (TFGIC) was used to study 234U(n,f) between En = 0.2 and 5.0 MeV. The reaction is important for fission modelling of the second-chance fission in 235U(n,f). The fission fragment (FF) angular-, energy and mass distributions were determined using the 2E-method highlighting especially the region of the vibrational resonance at En = 0.77...

  7. Lightcurves and Derived Rotation Periods for 18 Melpomene, 234 Barbara 236 Honoria, 520 Franziska, and 525 Adelaide

    Pilcher, Frederick

    2014-07-01

    From new lightcurves obtained near their 2014 oppositions rotation periods and amplitudes are found for 18 Melpomene 11.571 ± 0.002 hours, 0.16 ± 0.02 magnitudes; 234 Barbara 26.473 ± 0.002 hours, amplitude 0.16 ± 0.02 magnitudes; 236 Honoria 12.336 ± 0.001 hours, 0.23 ± 0.02 magnitudes; 520 Franziska 16.507 ± 0.001 hours, 0.35 ± 0.02 magnitudes; and 525 Adelaide 19.967 ± 0.001 hours, amplitude 0.35 ± 0.03 magnitudes near celestial longitude 180 degrees and 0.02 ± 0.01 magnitudes at celestial longitude 57 degrees, latitude -4 degrees. The amplitude - aspect method strongly suggests the latter position lies within a few degrees of one of the two rotational poles.

  8. Polonium 210Po, uranium (234U, 238U and plutonium (238Pu, 239+240Pu bioaccumulation in marine birds

    Strumińska-Parulska D. I.

    2013-04-01

    Full Text Available The aim of this work was the determination of 210Po, 234U, 238U, 238Pu and 239+240Pu concentration in marine birds which permanently or temporally live in the southern Baltic Sea coast. We chose 11 species of seabirds: three species permanently residing at southern Baltic Sea, four species of wintering birds and three species of migrating birds. The results show that analyzed radionuclides are non-uniformly distributed in the marine birds. The highest activities of 210Po were observed in feathers, muscles and liver. The highest uranium content was found in liver, rest of viscera and feathers, while plutonium in the digestion organs and feathers. Omnivore seabirds accumulated more polonium, plutonium than species that feed on fish, while herbivore seabirds accumulated more uranium than carnivore.

  9. Neutron emission effects on final fragments mass and kinetic energy distribution from low energy fission of 234U

    Montoya, M.; Rojas, J.; Lobato, I.

    2008-01-01

    Las mediciones sobre la desviación estándar de la distribución de energía cinetica final (σe) en función de la masa final (m) de los fragmentos de la fisión de baja energía del 234U, hechas por Belhafaf et al., presentan un pico alrededor de m = 109 y otro alrededor de m = 122. Los autores atribuyen el primer pico a la evaporación de un elevado número de neutrones alrededor del correspondiente número másico, es decir que no hay un pico en la desviación estándar de la distribución de ener...

  10. Fission Fragment Angular Distributions in the $^{234}$U(n,f) and $^{236}$U(n,f) reactions

    We propose to measure the fission fragment angular distribution (FFAD) of the $^{234}$U(n,f) and $^{236}$U (n,f) reactions with the PPAC detection setup used in previous n_TOF-14 experiment. This experiment would take advantage of the high resolution of the n_TOF facility to investigate the FFAD behaviour in the pronounced vibrational resonances that have been observed between 0.1 and 2 MeV for the thorium cycle isotopes. In addition, the angular distribution of these isotopes will be measured for the first time beyond 14 MeV. Furthermore, the experiment will also provide the fission cross section with reduced statistical uncertainty, extending the $^{236}$U(n,f) data up to 1 GeV

  11. Final results of the international 235U sample intercomparison and the half-life of 234U

    Finalized values were received from all laboratories which contributed samples to the 235U mass intercomparison carried out at Argonne National Laboratory. A least-squares fit was made which included the quoted masses and the absolute low-geometry and relative 2π-geometry alpha data as well as the relative fission ratios measured at ANL. Correlations between the measured values were taken into account. The values quoted by the contributing laboratories were found to be within +-0.35% of the values obtained from the LS fit. Very precise values for the isotopic composition were known for two of the sample materials which permitted a determination of the half-life of 234U. The value obtained is Tsub(1/2)=(2.457+-0.005)x105 years. Including this value in the present data base results in a current best value of Tsub(1/2)=(2.4566+-0.0044)x105 years. (author)

  12. Coupled {sup 230}Th/{sup 234}U-ESR analyses for corals: A new method to assess sealevel change

    Blackwell, Bonnie A.B. [Department of Chemistry, Williams College, Williamstown, MA 01267 (United States); RFK Science Research Institute, Glenwood Landing, NY 11547 (United States)], E-mail: bonnie.a.b.blackwell@williams.edu; Teng, Steve J.T. [RFK Science Research Institute, Glenwood Landing, NY 11547 (United States)], E-mail: mteng1584@gmail.com; Lundberg, Joyce A. [Department of Geography and Environmental Studies, Carleton University, Ottawa, ON, Canada K1S 5B6 (Canada)], E-mail: joyce_lundberg@carleton.ca; Blickstein, Joel I.B. [Department of Chemistry, Williams College, Williamstown, MA 01267 (United States); RFK Science Research Institute, Glenwood Landing, NY 11547 (United States); Skinner, Anne R. [Department of Chemistry, Williams College, Williamstown, MA 01267 (United States); RFK Science Research Institute, Glenwood Landing, NY 11547 (United States)], E-mail: anne.r.skinner@williams.edu

    2007-07-15

    Although coupled {sup 230}Th/{sup 234}U-ESR analyses have become routine for dating teeth, they have never been used for corals. While the ESR age depends on, and requires assumptions about, the time-averaged cosmic dose rate, D-bar{sub cos}(t), {sup 230}Th/{sup 234}U dates do not. Since D-bar{sub cos}(t) received by corals depends on the attenuation by any intervening material, D-bar{sub cos}(t) response reflects changing water depths and sediment cover. By coupling the two methods, one can determine the age and a unique D-bar{sub cos,coupled}(t) simultaneously. From a coral's water depth and sedimentary history as predicted by a given sealevel curve, one can predict D-bar{sub cos,sealevel}(t). If D-bar{sub cos,coupled}(t) agrees well with D-bar{sub cos,sealevel}(t), this provides independent validation for the curve used to build D-bar{sub cos,sealevel}(t). For six corals dated at 7-128 ka from Florida Platform reef crests, the sealevel curve by Waelbroeck et al. [2002. Sea-level and deep water temperature changes derived from benthonic foraminifera isotopic records. Quat. Sci. Rev. 21, 295-305] predicted their D-bar{sub cos,coupled}(t) values as well as, or better than, the SPECMAP sealevel curve. Where a whole reef can be sampled over a transect, a precise test for sealevel curves could be developed.

  13. Coupling groundwater residence time and 234U/238U isotopic ratios in a granitic catchment (Vosges, Eastern France)

    Viville, Daniel; Aquilina, Luc; Ackerer, Julien; Chatton, Eliot; Labasque, Thierry; Pierret, Marie-Claire; Granet, Mathieu; Perrone, Thierry; Chabaux, François

    2016-04-01

    Weathering processes are active in surface waters but groundwater also represents no neglectable chemical fluxes. As residence-time in groundwater are high, silicate weathering might take place and control Si, Ca and C fluxes. Weathering processes can be deduced from U isotopic ratios but the kinetics of these processes remain relatively poorly constrained. In order to better characterize these processes, we have coupled residence-times deduced from anthropogenic gases (CFC and SF6) analysis and 234U/238U isotopic ratios determination. Samples were collected in the Strengbach catchment (Hydro-geochemical Observatory OHGE, Vosges, eastern France). Two campaigns were carried out in May and August 2015 during two highly contrasted hydro-climatic periods. Both springs and boreholes down to 80 m depth have been sampled. A very clear geochemical distinction is observed between groundwater from surface springs and deeper groundwater from boreholes. Springs show much lower residence-time (few years) and specific chemical composition. Deeper groundwater have residence-time of several decades and different geochemical composition. A clear SF6 production is observed with increasing SF6 concentrations with residence-time. The campaign of May is characterized by highly groundwater levels and spring fluxes. All groundwater show very low residence time, except in the boreholes at depth greater than 40 m. Conversely, during low groundwater-level period in August, the residence times are much higher and CFC concentrations indicate a large mixing process between surface groundwater and deeper levels. The 234U/238U isotopic ratios confirm this vertical zonation in the boreholes, with much higher activity ratios in the deep ground-waters from borehole than in the surface and spring waters; Such high U activity ratios are indicative of long water-rock interactions, which is consistent with the long residence times deducted from the CFC and SF6 data.

  14. Direct comparison of {sup 210}Po, {sup 234}Th and POC particle-size distributions and export fluxes at the Bermuda Atlantic Time-series Study (BATS) site

    Stewart, Gillian, E-mail: gstewart@qc.cuny.ed [Queens College, CUNY Flushing, NY 11367 (United States); Moran, S. Bradley, E-mail: moran@gso.uri.ed [Graduate School of Oceanography, URI Narragansett, RI 02882 (United States); Lomas, Michael W., E-mail: Michael.Lomas@bios.ed [Bermuda Institute for Ocean Sciences, St. George' s, GE01 (Bermuda); Kelly, Roger P., E-mail: rokelly@gso.uri.ed [Graduate School of Oceanography, URI Narragansett, RI 02882 (United States)

    2011-05-15

    Particle-reactive, naturally occurring radionuclides are useful tracers of the sinking flux of organic matter from the surface to the deep ocean. Since the Joint Global Ocean Flux Study (JGOFS) began in 1987, the disequilibrium between {sup 234}Th and its parent {sup 238}U has become widely used as a technique to measure particle export fluxes from surface ocean waters. Another radionuclide pair, {sup 210}Po and {sup 210}Pb, can be used for the same purpose but has not been as widely adopted due to difficulty with accurately constraining the {sup 210}Po/{sup 210}Pb radiochemical balance in the ocean and because of the more time-consuming radiochemical procedures. Direct comparison of particle flux estimated in different ocean regions using these short-lived radionuclides is important in evaluating their utility and accuracy as tracers of particle flux. In this paper, we present paired {sup 234}Th/{sup 238}U and {sup 210}Po/{sup 210}Pb data from oligotrophic surface waters of the subtropical Northwest Atlantic and discuss their advantages and limitations. Vertical profiles of total and particle size-fractionated {sup 210}Po and {sup 234}Th activities, together with particulate organic carbon (POC) concentrations, were measured during three seasons at the Bermuda Atlantic Time-series Study (BATS) site. Both {sup 210}Po and {sup 234}Th reasonably predict sinking POC flux caught in sediment traps, and each tracer provides unique information about the magnitude and efficiency of the ocean's biological pump.

  15. 234U/238U isotope data from groundwater and solid-phase leachate samples near Tuba City Open Dump, Tuba City, Arizona

    Johnson, Raymond H.; Horton, Robert J.; Otton, James K.; Ketterer, Michael K.

    2012-01-01

    This report releases 234U/238U isotope data, expressed as activity ratios, and uranium concentration data from analyses completed at Northern Arizona University for groundwater and solid-phase leachate samples that were collected in and around Tuba City Open Dump, Tuba City, Arizona, in 2008.

  16. 20 CFR 408.234 - Can you continue to receive SVB payments if you stay in the United States for more than 1 full...

    2010-04-01

    ... your foreign residence to continue. We will continue to consider you to be a foreign resident and will... Qualification and Entitlement Residence Outside the United States § 408.234 Can you continue to receive SVB... you to have lost or abandoned your foreign resident status for SVB purposes and we will stop your...

  17. North Tien Shan: regularities in the distribution of excess uranium-234 anomalies in natural water with special reference to mineral occurrences

    It is shown, that correlation between the uranium-234 anomalous excess in underground waters and localization of non uranium ores is expressed in the areas of sedimentary and metamorphic ores. This regularity makes it possible to identify with higher probability large industrial deposits, which essentially change the uranium-isotope background in underground waters in the area of ores distribution

  18. Determination of technetium-99, thorium-230 and uranium-234 in soils by inductively coupled plasma mass spectrometry using flow injection preconcentration

    A new method is described for the determination of 99Tc, 230Th, and 234U at ultra-trace levels in soils. The method used flow injection (FI) for on-line preconcentration of 99Tc, 230Th and 234U prior to detection using inductively coupled plasma mass spectrometry (ICP-MS). The FI-ICP-MS method results in greater sensitivity and freedom from interferences compared with direct aspiration into an ICP mass spectrometer. Detection limits are improved by approximately a factor of 10. The FI-ICP-MS method is also faster, less labour intensive and generates less laboratory waste than traditional radiochemical methods. The accuracy of the method was tested for 99Tc by comparison to liquid scintillation counting and for 230Th and 234U by analysis of a US Department of Energy reference soil. Detection limits in the soil for 99Tc, 230Th and 234U were 11 mBq g-1 (0.02 ng g-1), 3.7 mBq g-1 (0.005 ng g-1) and 0.74 mBq g-1 (0.003 ng g-1), respectively. Sample preparation, analysis protocol, and method validation are described. (Author)

  19. Seasonal changes of 234Th scavenging in surface water across the western Black Sea: an implication of the cyclonic circulation patterns

    Two seasonal surveys of 234Th activity in surface water were carried out in November 1998 and June 1999 along the transect Sevastopol (Ukraine) - Istanbul (Turkey) crossing the entire western Black Sea between the SW Crimean Peninsula and the Bosphorus Strait entry. A steady-state model of 234Th/238U equilibrium in seawater was used to calculate the net removal flux of 234Th by particles. The results obtained from central stations of the transect were in good agreement with those observed seasonally in 1992-1994 within the western cyclonic gyre of the abyssal Black Sea, showing that in June 1999 the sampling was conducted during the peak summer bloom of coccolithophorids, while in November 1998 the samples were collected three weeks after the autumn phytoplankton bloom. The 234Th scavenging rates and the total mass fluxes were thus much higher in the June sampling period than in November at the stations located in the western cyclonic gyre and at the northern margin of the abyssal Black Sea basin. In contrast, the considerable seasonal differences were not found at the location near the Bosphorus Strait entry, suggesting a larger lateral input of particulate matter transported to this area from the western and northwestern shelf due to cyclonic circulation of the surface waters

  20. Sequence and analysis of the rpoN sigma factor gene of rhizobium sp. strain NGR234, a primary coregulator of symbiosis.

    van Slooten, J C; Cervantes, E; Broughton, W J; Wong, C H; Stanley, J

    1990-01-01

    We report the nucleotide sequence of the rpoN gene from broad-host-range Rhizobium sp. strain NGR234 and analyze the encoded RPON protein, a sigma factor. Comparative analysis of the deduced amino acid sequence of RPON from NGR234 with sequences from other gram-negative bacteria identified a perfectly conserved RPON box unique to RPON sigma factors. Symbiotic regulatory phenotypes were defined for a site-directed internal deletion within the coding sequence of the rpoN gene of Rhizobium strain NGR234: they included quantitative nodulation kinetics on Vigna unguiculata and microscopic analysis of the Fix- determinate nodules of V. unguiculata and Macroptilium atropurpureum. RPON was a primary coregulator of nodulation and was implicated in establishment or maintenance of the plant-synthesized peribacteroid membrane. Phenotypes of rpoN in Rhizobium strain NGR234 could be grouped as symbiosis related, rather than simply pleiotropically physiological as in free-living bacteria such as Klebsiella pneumoniae and Pseudomonas putida. Images PMID:2211497

  1. Determination of 234U and 238U activity concentrations in groundwaters from three deep wells drilled in Itu Intrusive Suite (SP)

    Activity concentrations of (234U) and (238U) were determined in groundwaters drawn from three deep wells drilled in rocks from Itu Intrusive Suite (SP), two located in Salto town (S and SY wells) and the other one in Itu (I well). Sampling was done from September, 2004 to December, 2005, and twelve samples of each well were collected monthly. For those determinations alpha spectrometry technique was used, providing high precision results, as shown by the very good agreement of the data obtained in the analyses of 23 duplicates. The waters from the three wells presented a considerable enrichment of 234U in relation to 238U, indicating an important radioactive disequilibrium of these isotopes. In well I, the activity concentrations of (238U) varied from (1,06 +- 0,03) to (2,1+- 0,2) mBq/L and those of (234U) spanned from (3,1 +- 0,2) to (6,0 +- 0,4) mBq/L, whereas (234U/238U) activity ratios did not present significant variation, during the sampling time interval, presenting an average of 2,8 +- 0,1. The S waters showed the lowest uranium concentrations and the largest diversity of (238U) and (234U) activity concentrations, which varied from (0,26 +- 0,02) to (1,07+- 0,08) mBq/L and from (1,8 +- 0,1) to (7,0 +- 0,5) mBq/L, respectively, and also presented variable (234U/238U) activity ratios, spanning from (2,79 +- 0,07) to (8,1+- 0,3). In SY well, (238U) activities varied between (0,8 +- 0,1) and (4,2 +- 0,3) mBq/L and those ones of (234U) from (14 +- 1) to (53 +- 4) mBq/L, whereas (234U/238U) ratios fell in the interval from 12,6 +- 0,3 to 18,3 +- 0,4, with the highest activities of both radioisotopes registered during the dry season and the lowest ones in the rainy time period. The (234U/238U) activity ratios, which were invariable during sampling period of well I, indicated the contribution of rainfall to recharge the aquifer. The observed correlation between those ratios and uranium concentrations, for S and SY wells, showed complex and distinct recharging

  2. Corrective Action Decision Document/Closure Report for Corrective Action Unit 234: Mud Pits, Cellars, and Mud Spills Nevada Test Site, Nevada, Revision 0

    Grant Evenson

    2008-05-01

    This Corrective Action Decision Document/Closure Report has been prepared for Corrective Action Unit (CAU) 234, Mud Pits, Cellars, and Mud Spills, located in Areas 2, 3, 4, 12, and 15 at the Nevada Test Site, Nevada, in accordance with the Federal Facility Agreement and Consent Order (FFACO, 1996; as amended February 2008). Corrective Action Unit 234 is comprised of the following 12 corrective action sites: •02-09-48, Area 2 Mud Plant #1 •02-09-49, Area 2 Mud Plant #2 •02-99-05, Mud Spill •03-09-02, Mud Dump Trenches •04-44-02, Mud Spill •04-99-02, Mud Spill •12-09-01, Mud Pit •12-09-04, Mud Pit •12-09-08, Mud Pit •12-30-14, Cellar •12-99-07, Mud Dump •15-09-01, Mud Pit The purpose of this Corrective Action Decision Document/Closure Report is to provide justification and documentation supporting the recommendation for closure of CAU 234 with no further corrective action. To achieve this, corrective action investigation (CAI) activities were performed as set forth in the Corrective Action Investigation Plan for Corrective Action Unit 234: Mud Pits, Cellars, and Mud Spills (NNSA/NSO, 2007). The purpose of the CAI was to fulfill the following data needs as defined during the data quality objective (DQO) process: •Determine whether contaminants of concern are present. •If contaminants of concern are present, determine their extent. •Provide sufficient information and data to complete appropriate corrective actions. The CAU 234 dataset from the investigation results was evaluated based on the data quality indicator parameters. This evaluation demonstrated the quality and acceptability of the dataset for use in fulfilling the DQO data needs.

  3. The behavior of particle-reactive tracers in a high turbidity environment: 234Th and 210Pb on the Amazon continental shelf

    Excess 234Th and 210Pb seabed inventories were measured in cores collected from the Amazon continental shelf to examine particle scavenging and seabed dynamics. Typical excess 210Pb inventories range from 100 to 300 dpm cm-2, and the total excess 210Pb inventory for the Amazon shelf was determined to be 2.7 x 1017 dpm. The 210Pb measurements indicate that particle-reactive species are scavenged not only form the Amazon River but also from the lateral advection of offshore water. In order to sustain the 210Pb inventories, the volume of water supplied by the lateral advection from offshore must be approximately five to ten times the water discharge of the Amazon River. This lateral advection supplies about 67% of the total excess 210Pb to the Amazon continental shelf with relatively small contributions from riverine input (31%), atmospheric fallout (2.3%), and in-situ production (0.1%). The 234Th inventories were measured on four cruises, which occurred during periods of differing river discharge, wind stress, and flow rates of the North Brazil Current. The 234Th excess seabed inventories show large spatial and seasonal variability, with a range from 0 to 22 dpm cm-2. This approach indicates that for most of the shelf, the inventories of the shorter-term tracer (234Th) are less than predicted by the inventories of the longer-term tracer (210Pb). There are two explanations for this trend. The first is that a larger portion of the 234Th inventory occurs in the fluid muds or the water column relative to 210Pb. The second is that the supply of offshore water, scavenging efficiency, and/or deposition have been lower over the two year study period relative to the last one hundred years. 38 refs., 7 figs

  4. Application of natural Ra isotopes and {sup 234}Th as tracers of organic carbon export in Bransfield Strait, Antarctica; Aplicacao dos isotopos naturais de Ra e do Th-234 como tracadores do carbono organico exportado para o Estreito de Bransfield, Antartica

    Vieira, Lucia Helena

    2011-07-01

    The Southern Ocean is the largest of several high-nutrient, low-chlorophyll (HNLC) regions in the world's oceans. This region plays a major role in regulating the global net transfer of carbon dioxide between the ocean and the atmosphere, in part because the annual photosynthetic uptake of CO{sub 2} by phytoplankton and resulting export of particulate organic carbon (POC) to the deep ocean. The element thorium has multiple radioisotopes that have emerged collectively as a powerful set of tracers for particle associated processes in the oceans. Of all the Th isotopes, {sup 234}Th (half-life 24.1 d) has been the focus of increasing attention and application in the past years. The production of {sup 234}Th from {sup 238}U, coupled with the conservative behavior of {sup 238}U in seawater, makes the source of {sup 234}Th easy to characterize. Moreover, the half-life of {sup 234}Th is sufficiently short to make it sensitive to the short-term (e.g. seasonal) changes that occur in the upper water column of the open ocean or in sediments or water column in coastal areas. Because of its very particle reactive behavior, {sup 234}Th is removed from a parcel of water in only two ways, through decay and through particle flux. Therefore, a steady-state 1D activity balance can be used to calculate its flux. Natural Ra isotopes have been also widely used in marine studies to trace water masses and to quantify mixing processes. This work presents results of a collaborative research on organic carbon fluxes distribution in the Bransfield Strait in order to evaluate its influence in the CO{sub 2} drawdown. Macro-nutrients, micro-nutrients and chlorophyll-a distributions were used to examine the pathway sources. Natural radium isotopes were applied as tracers to study the movement of shelf water, while {sup 234}Th was used as a tracer of particle flux in the upper ocean, since POC export via sinking particles is the primary mechanism of carbon sequestration in the Southern Ocean

  5. Accidental nuclear excursion Recuplex operation 234-5 facility. Final report: Date of incident: April 7, 1962

    1962-08-01

    On Saturday morning, April 7, 1962, at about 1059 Armed Forces time, an accidental nuclear excursion occurred in the plutonium waste recovery facility (Recuplex) of the 234-5 Building. This excursion did not result in any mechanical damage or spread of contamination. Three employees of the General Electric Company received overexposures to gamma and neutron radiation. None were fatally exposed; in each case the overexposure was recognized promptly, and following medical observation and testing the men were released to return to work. In compliance with AEC Manual Chapter 0703, an AEC-HAPO committee composed of two AEC employees and five General Electric employees was appointed by the Manger, HOO, with the concurrence of the General Manager, HAPO, to conduct an investigation of the incident. The committee`s purpose was to determine the cause, nature, and extent of the incident, and recommend action to be taken by others to minimize or preclude future incidents of this magnitude. A study of operating practices and operating conditions that appeared to exist prior to, during, and subsequent to the accident was made by the committee. The committee believes that this report provides sufficient information to answer questions which may arise as a result of the criticality incident except those relating to its cause.

  6. Prognosis of 234 rosacea patients according to clinical subtype: The significance of central facial erythema in the prognosis of rosacea.

    Lee, Woo Jin; Lee, Ye Jin; Lee, Mi Hye; Won, Chong Hyun; Chang, Sung Eun; Choi, Jee Ho; Lee, Mi Woo

    2016-05-01

    Rosacea has a wide spectrum of clinical features, which include persistent facial redness, flushing, telangiectasia, inflammatory papules/pustules, hypertrophy and/or ocular features. The prognosis of rosacea according to clinical subtype has not been evaluated. We analyzed the prognosis of rosacea in 234 patients, which included 120 patients with mixed subtype, 75 with the erythematotelangiectatic rosacea subtype and 39 with the papulopustular rosacea (PPR) subtype. The prognosis of rosacea was classified as: (i) no improvement; (ii) partial remission; and (iii) complete remission. The frequencies of complete remission, time to complete remission and 1-year complete remission rate were compared between subtypes. Follow-up periods ranged 2-72 months (median follow-up, 17.5). Aggravation of the disease was found in 50.4% of patients during follow up. Partial or complete remission was noted in 61.5% and 20.9% of patients, respectively. The median time to complete remission was 56.0 months. The prognosis of disease was more favorable for patients with the PPR subtype than for patients with other subtypes with respect to the frequency of complete remission, median time to complete remission and the 2-year complete remission rate. In conclusion, papulopustular rosacea without remarkable centrofacial erythema showed a more favorable prognosis than other subtypes. Erythematotelangiectatic lesions in rosacea patients present a challenge for the treatment of rosacea. PMID:26507367

  7. Determination of distribution coefficients for 134 Cs, 60 Co and 234 Th radionuclides in Pinheiro river sediment

    The distribution coefficients (K α) were determined in order to foresee the fate of the radionuclides discharged to the environment. Based upon the source-term released by IPEN's facilities in Pinheiros River during the year of 1988, three radionuclides were chosen as being the more critical, according to the radiation protection standards: 137 Cs, 60 Co and 232 Th. Their K α were determined experimentally in laboratory by using the corresponding radioactive tracers 134 Cs, 60 Co and 234 Th. Three different experimental methodologies were used: the static method, the shaken method and the dynamic method. The parameters studied were the effects of pH, aerobic condition and time of contact. The results obtained experimentally for the Kds confirm the predictions that: the cesium is slowly retained by the sediment along the Pinheiros River, the cobalt is an unstable element, therefore its retention by the sediment is affected by variations in the pH values, and finally, the thorium is almost completely retained in the vicinity of the discharge point. (author)

  8. SMA observations towards the compact, short-lived bipolar water maser outflow in the LkH{\\alpha} 234 region

    Girart, J M; Estalella, R; Curiel, S; Anglada, G; Gómez, J F; Carrasco-González, C; Cantó, J; Rodríguez, L F; Patel, N A; Trinidad, M A

    2016-01-01

    We present Submillimeter Array (SMA) 1.35 mm subarcsecond angular resolution observations toward the LkH{\\alpha} 234 intermediate-mass star-forming region. The dust emission arises from a filamentary structure of $\\sim$5 arcsec ($\\sim$4500 au) enclosing VLA 1-3 and MM 1, perpendicular to the different outflows detected in the region. The most evolved objects are located at the southeastern edge of the dust filamentary structure and the youngest ones at the northeastern edge. The circumstellar structures around VLA 1, VLA 3, and MM 1 have radii between $\\sim$200 and $\\sim$375 au and masses in the $\\sim$0.08-0.3 M$_{\\odot}$ range. The 1.35 mm emission of VLA 2 arises from an unresolved (r$< 135$ au) circumstellar disk with a mass of $\\sim$0.02 M$_{\\odot}$. This source is powering a compact ($\\sim$4000 au), low radial velocity ($\\sim$7 km s$^{-1}$) SiO bipolar outflow, close to the plane of the sky. We conclude that this outflow is the "large-scale" counterpart of the short-lived, episodic, bipolar outflow ob...

  9. Gamma-Ray Emission Spectra as a Constraint on Calculations of 234 , 236 , 238U Neutron-Capture Cross Sections

    Ullmann, J. L.; Krticka, M.; Kawano, T.; Bredeweg, T. A.; Baramsai, B.; Couture, A.; Haight, R. C.; Jandel, M.; Mosby, S.; O'Donnell, J. M.; Rundberg, R. S.; Vieira, D. J.; Wilhelmy, J. B.; Becker, J. A.; Wu, C. Y.; Chyzh, A.

    2015-10-01

    Calculations of the neutron-capture cross section at low neutron energies (10 eV through 100's of keV) are very sensitive to the nuclear level density and radiative strength function. These quantities are often poorly known, especially for radioactive targets, and actual measurements of the capture cross section are usually required. An additional constraint on the calculation of the capture cross section is provided by measurements of the cascade gamma spectrum following neutron capture. Recent measurements of 234 , 236 , 238U(n, γ) emission spectra made using the DANCE 4 π BaF2 array at the Los Alamos Neutron Science Center will be presented. Calculations of gamma-ray spectra made using the DICEBOX code and of the capture cross section made using the CoH3 code will also be presented. These techniques may be also useful for calculations of more unstable nuclides. This work was performed with the support of the U.S. Department of Energy, National Nuclear Security Administration by Los Alamos National Security, LLC (Contract DE-AC52-06NA25396) and Lawrence Livermore National Security, LLC (Contract DE-AC52-07NA2734).

  10. Bioaccumulation of polonium (210Po, uranium (234U, 238U isotopes and trace metals in mosses from Sobieszewo Island, northern Poland

    Boryło A.

    2013-04-01

    Full Text Available The objective of this study was determination of the polonium (210Po, uranium (234U and 238U radionuclides and trace metals (Pb, Fe, Zn, Cu, Ni, Cd, Hg concentrations in mosses samples from Sobieszewo Island near the phosphogypsum waste dump in Wiślinka (northern Poland. The obtained results revealed that the concentrations of 210Po, 234U, and 238U in the two analyzed kinds of mosses: Pleurozium schreberi and Dicranum scoparium were similar. Among the analyzed trace metals the highest concentration in mosses was recorded for iron, while the lowest for nickel, cadmium and mercury. The obtained studies showed that the sources of polonium and uranium isotopes, as well as trace metals in analyzed mosses are air city contaminations transported from Gdańsk and from existing in the vicinity the phosphogypsum waste heap in Wiślinka (near Gdańsk.

  11. Desequilibri 234Th/238U per a l'estudi del cicle de partícules al Mediterrani nord-occidental

    Bermejo Cisneros, Mercè; Masqué Barri, Pere

    2010-01-01

    El desequilibri 238U/234Th s'utilitza per traçar el cicle de les partícules a la part més superficial dels oceans. Això és possible degut a les diferències entre els seus períodes de semidesintegració (T1/2 (234Th)=24,1 d; T1/2 (238U)=4,5 10 9 anys) i a les seves característiques biogeoquímiques: el Th presenta una gran afinitat per les partícules mentre que l'U és conservatiu en aigua de mar. En absència de partícules s'esperaria tenir equilibri secular entre ambdós radionúclids, però com qu...

  12. Evaluation of the extractive procedure for determination of 238U and 234U in groundwater and comparison with traditional α-spectrometry technique

    Photon/Electron Rejecting Alpha Liquid Scintillation (PERALS) spectrometry has been used for the determination of uranium radionuclides in the ground water samples. The technique utilizes a commercially available extractive scintillant URAEX, which is selective for uranium. The cocktail extracted uranium from aqueous medium quantitatively and the efficiency of extraction was nearly 100% with no self-absorption or geometry problems. This method applies to pulse-shape discrimination of PERALS counting spectrometry and completely separates the alpha activity from the beta/gamma background. The resolutions of the 238U, 234U and 232U obtained in this method were good enough to for measurement of uranium isotopes in a quantitative way. The lower limit of detection was found to be 2.0 mBq l-1 for 2 hours counting time for a sample volume of 200 ml. The levels of 238U and 234U concentrations in groundwater samples of several locations were found to range from 12.8 ± 1.0 to 148.3 ± 10.8 mBq l-1 and 16.1 ± 1.2 to 106.7 ± 8.2 mBq l-1, respectively. For the bottled drinking water samples collected from markets, the 238U and 234U concentrations were found to range from below detectable level (BDL) to 38.7 ± 2.4 mBq l-1 and 47.3 ± 2.8 mBq l-1, respectively. The results of uranium radionuclides (238U and 234U) in groundwater and bottled water samples measured by PERALS method were compared with that obtained by alpha spectrometric method. (author)

  13. Temporal evolution of natural radionuclides distributions 238U, 234Th, 226Ra, 228Ra, 210Pb and 210Po in the Bransfield strait, Antarctica peninsula

    Research on the distribution of natural radionuclides in Antarctica is rare and thus, there is great interest in to know their occurrence and factors related to its mobilization, transference and accumulation in this extremely fragile environment. Natural radionuclides have been used intensively as tracers in the ocean, helping to better understand processes as sinking and particle resuspension, water masses mixture and oceanic circulation. 234Th (t½ = 24.1 days) is a particle-reactive radionuclide produced continuously in seawater by the decay of its soluble precursor conservative with salinity 238U (t½ = 4.5 109 years). Since 234Th presents relatively short half-life, it is used to quantify processes that occur in temporal scale varying from days to weeks. The disequilibrium 234Th/238U in the surface ocean has been applied to estimate carbon fluxes exported via sinking material. The flux of particles biologically productive out of the euphotic zone in the Southern Ocean has special attention due to its importance in the control of CO2 atmospheric concentrations. The radionuclides 210Pb (t½ = 22.3 years) and 210Po (t½ = 138 days) are also particle-reactive. The disequilibrium 210Po/210Pb has been used to estimate fluxes of particles exported in the ocean in the time scale of weeks. The long-lived Ra isotopes, 226Ra (t½ = 1,600 years) and 228Ra (t½ = 5.75 years) are soluble in seawater, presenting unique properties that make them excellent tracers of water masses. This research work had the aim to study the distributions of natural radionuclides 238U, 234Th, 22'6Ra, 22'8Ra, 210Pb and 210Po in the Bransfield Strait during 2 samplings carried out in the 2011 Austral Summer (OPERANTAR XXIX and XXX). (author)

  14. Application of 234U/238U isotope ratio data for the study of geochemical problems associated with local water sources from Aguas da Prata (SP, Brazil)

    The uranium-238, uranium-234 and radon content of spring waters of Aguas da Prata (SP) - Platina, Paiol, Villela, Sao Bento, Prata-Radioativa, Prata-Nova, Boi, Vitoria and Prata-Antiga - was found; the activity ratio AR (234U/238U) was applied to the geochemistry of local water sources. The uranium analysis procedure consisted of the following steps: adition of 232U-228Th spike to the samples, coprecipitation with iron, iron extraction with organic solvent, separation on anion-exchange resin, extraction with TTA, deposition on stainless steel disc and determination of uranium content by alpha spectrometry. The uranium-238 content changed from 0,10 to 11,56 ppb (average value = 2,3 ppb). The higher values were observed for the waters circulating through sandstones and the lower through volcanic rocks. The inverse correlation (r sub(s) =-0,76) between pH and uranium-238 content confirmed the contribution of this factor on its solubility. The significative correlation r sub(s) = 0,76 between dissolved oxygen and uranium-238 content also confirmed the higher uranium on the more oxidizing zones. The AR changed from 2,84 to 11,68 (average value = 6). These values defined the regional aquifer systems as mineralized in uranium. The higher AR were observed for the deep groundwaters and the lower for the shallow one. Because the 238U→234Th decay, the 234Th ejection to the solution was confirmed as the most important factor responsible for the extreme observed isotopic fractionation. (Author)

  15. Mutation of G234 amino acid residue in candida albicans drug-resistance-related protein Rta2p is associated with fluconazole resistance and dihydrosphingosine transport.

    Zhang, Shi-Qun; Miao, Qi; Li, Li-Ping; Zhang, Lu-Lu; Yan, Lan; Jia, Yu; Cao, Yong-Bing; Jiang, Yuan-Ying

    2015-01-01

    Widespread and repeated use of azoles has led to the rapid development of drug resistance in Candida albicans. Our previous study found Rta2p, a membrane protein with 7 transmembrane domains, was involved in calcineurin-mediated azole resistance and sphingoid long-chain base release in C. albicans. Conserved amino acids in the transmembrane domain of Rta2p were subjected to site-directed mutagenesis. The sensitivity of C. albicans to fluconazole in vitro was examined by minimum inhibitory concentration and killing assay, and the therapeutic efficacy of fluconazole in vivo was performed by systemic mice candidiasis model. Furthermore, dihydrosphingosine transport activity was detected by NBD labeled D-erythro-dihydrosphingosine uptake and release assay, and the sensitivity to sphingolipid biosynthesis inhibitors. We successfully constructed 14 mutant strains of Rta2p, screened them by minimum inhibitory concentration and found Ca(2+) did not completely induce fluconazole resistance with G158E and G234S mutations. Furthermore, we confirmed that G234S mutant enhanced the therapeutic efficacy of fluconazole against systemic candidiasis and significantly increased the accumulation of dihydrosphingosine by decreasing its release. However, G158E mutant didn't affect drug therapeutic efficacy in vivo and dihydrosphingosine transport in C. albicans. G234 of Rta2p in C. albicans is crucial in calcineurin-mediated fluconazole resistance and dihydrosphingosine transport. PMID:26220356

  16. Experimental study of the neutron induced fission cross-section of 234U, 237Np and 243Am with time-of-flight spectrometry technics

    The current work concentrates on the measurements of the nuclear data needed for solving the problem of transmutation of radiotoxic waste. It includes fission cross-section of 234U in the energy range from thermal to 1 MeV, 237Np and 243Am in the resonance region and average group capture cross-section of 234U and 236U. Almost all of these data are recommended by IAEA as a first priority needs for transmutation problem. Another objective is to obtain the high resolution data of the fission cross-section of the 234U on the fission barrier to confirm the existence of the fine structure, attributed to the vibrational resonances in the third well of the fission barrier. The Dissertation summarizes more, than 10 years of the experiments, performed on the pulsed neutron sources IBR-2 and IBR-30 of Frank Laboratory of Neutron Physics of the Joint Institute for Nuclear Research (FLNP JINR) in Dubna, Russia; 'Fakel' of Russian Scientific Center 'Kurchatov's Institute' and n-TOF of CERN. The TOF technique was used for neutron energy spectrometry and various kinds of detectors to mark the fission events. The independent measurements of the same isotopes done on different neutron sources and sometimes with different techniques gives strong, self-consistent set of data. (author)

  17. Early diagenesis of travertine deposits from the Tibetan Plateau - implications for 230Th/234U dating and palaeoenvironmental reconstruction

    Wang, Zhijun; Meyer, Michael; Hoffmann, Dirk; Spötl, Christoph; Aldenderfer, Mark; Sanders, Diethard

    2014-05-01

    Travertine is calcium carbonate precipitated from hydrothermal springs. These terrestrial carbonate deposits can be used as high-resolution archives for reconstructing palaeoclimatic and palaeoenvironmental change and are also suitable for uranium-series disequilibrium (230Th/234U) dating. In many instances such spring deposits are associated with archaeological remains (e.g. stone artifacts and other traces of prehistoric human activity) and are therefore of interest for palaeoclimatologists and archaeologists alike. However, travertines are often affected by early diagenesis that can impact on the closed-system U-series behavior and on their geochemical signature. Hence, careful evaluation of the travertine microfabrics is required before these types of hot spring deposits can be accurately dated and used for paleoenviromental reconstruction. The Tibetan plateau hosts numerous hydrothermal spring deposits that occur along neotectonic faults. In this study, samples were collected from two archaeological travertine sites, i.e. Chusang and Tirthapuri, located in southern and western Tibet, respectively. Microscopic analysis of thin sections reveals a wide variety of crystal fabrics, including micrite, microspar and sparite, the latter can be composed of columnar or mosaic crystals, respectively. Areas where dendritic crystals are preserved are identified in our micrographs as well. Many of the Chusang and Tirthapuri travertine samples are porous. Drusy sparite is rimming most of the pore walls and a complex succession of secondary calcite phases precipitated in these pore spaces as well. The different generations of pore cement comprise micrite and sparite that can be laminated or fibrous in character and show sometimes evidence of an aragonite precursor. Detrital material like quartz, feldspar and other grains as well as humic and fulvic acids have been washed into the travertine pores too. Based on our microscopic analysis a complex growth history can be

  18. Catalytic and kinetic spectrophotometric method for determination of vanadium(V by 2,3,4-trihydroxyacetophenonephenylhydrazone

    P.V. Chalapathi

    2014-12-01

    Full Text Available A new catalytic and kinetic spectrophotometric method for the determination of vanadium(V was studied using 2,3,4-trihydroxyacetophenonephenylhydrazone (THAPPH as an analytical reagent. The present method was developed on the catalytic effect of vanadium on oxidation of THAPPH by hydrogen peroxide in hydrochloric acid–potassium chloride buffer (pH = 2.8 at the 20th minute. The metal ion has formed 1:2 (M:L complex with THAPPH. Beer’s law was obeyed in the range 20–120 ng/mL of V(V at λmax 390 nm. The sensitivity of the method was calculated in terms of molar absorptivity (1.999 × 105 L mol−1cm−1 and Sandell’s sensitivity (0.000254 μg cm−2, shows that this method is more sensitive. The standard deviation (0.0022, relative standard deviation (0.56%, confidence limit (±0.0015 and standard error (0.0007 revealed that the developed method has more precision and accuracy. The stability constant was calculated with the help of Asmu’s (9.411 × 10−11 and Edmond’s & Birnbaum’s (9.504 × 10−11 methods at room temperature. The interfering effect of various cations and anions was also studied. The present method was successfully applied for the determination of vanadium(V in environmental and alloy samples. The method’s validity was checked by comparing the results obtained with atomic-absorption spectrophotometry and also by evaluation of results using F-test.

  19. 'Destined for the downfall and rise of many in Israel': Luke 2:34b in patristic (and modern exegesis

    J. H. Barkhuizen

    1995-01-01

    Full Text Available A close reading of both patristic and modem exegetes points towards the existence of two main schools of thought, and the aim of this short paper is to introduce the main proponents of each school, stating both the basic notion of each and the biblical evidence serving as the basis for their subsequent argumentation. The paper concludes with some suggestions for further discussion What did Simeon mean when he referred to the child Jesus in Luke 2:34b, as the downfall and rise of many in Israel? A close reading of both patristic and modem exegetes points towards the existence of two main schools of thought 1. The prophecy of Simeon 'has usually been interpreted as the fall of some and the rising of others, that is a process of self-judgement in which men determine the verdict to be passed on their lives, by tile response they make to the coming of the Messiah' (Caird 1979:64. One very typical commentary within this school of thought is for example the following by Fritz Rienecker (1977:69: Es zeugt von einem tiefen Blick des alten Simeon, dass er die Verheis-sung des Jesaja (Kap  8,13-15 in  Christus sich erftillen sieht. Alle mussen in Israel an Ihm vorbei und keiner kann Ihn unbeachtet lassen. Israel ist 'Wie ein Strom, der sich an Christus, dem Felsen, brechen und zwiegeteilt weiterstromen wird. Dem einen zum Fall, dem andem zum Reil.

  20. Be-7 and Th-234 as tracers of sediment mixing on seasonal time at the water-sediment interface of the Thau pond

    We report detailed depth profiles of the particle-reactive radionuclides 234Th (24.1 days) and 7Be (53.3 days) in sediment cores collected at different seasons in the Thau Lagoon, located in the south of France. Cores were collected at two selected sites with contrasting characteristics: C4 in the middle of the lagoon and C5 nearby oyster farming. Both sites were visited six times between December 2001 and May 2003. 234Th in excess (234Thxs; i.e. supplied to sediment by settling particles) and 7Be both show seasonal variations in activities and in penetration within the sediment. Uppermost activities of 234Thxs and 7Be range between 20 and 72 mBq g-1 at site C4 and between 30 and 166 mBq g-1 at site C5. With their very short half-lives and moderate sedimentation rates at both sites (around 0.1 - 0.3 cm per year), 234Thxs and 7Be should be present only at the water-sediment interface. However all the profiles show penetration of both short-lived radionuclides to variable depths, from 1 up to 8 cm, that indicates efficient mixing of upper sediments, usually referred as bioturbation. The simplest way to calculate Db from radionuclide profiles assumes bioturbation as a diffusive process occurring at a constant rate within a surface mixed layer under steady state. For site C4, steady-state bioturbation rates range between 1 and 12 cm2 yr-1, with a weak seasonal signal. The mixing of surface sediments at site C5 presents a greater range (1 34 cm2 yr-1) with the highest values observed in summer. Such a time-series of short radionuclides at the water sediment is most unusual. It provides the opportunity to develop a non-steady state modeling in order to test the significance of bioturbation rates based on steady state assumption. Results of this test will be discussed. (author)

  1. Physical and underway data collected aboard the THOMAS G. THOMPSON during cruise TN234 in the South Pacific Ocean from 2009-05-05 to 2009-05-13 (NODC Accession 0104351)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104351 includes physical and underway data collected aboard the THOMAS G. THOMPSON during cruise TN234 in the South Pacific Ocean from 2009-05-05 to...

  2. Coulex fission of 234U, 235U, 237Np, and 238Np studied within the SOFIA experimental program

    SOFIA (Studies On FIssion with Aladin) is an experimental project which aims at systematically measuring the fission fragments' isotopic yields as well as their total kinetic energy, for a wide variety of fissioning nuclei. The PhD work presented in this dissertation takes part in the SOFIA project, and covers the fission of nuclei in the region of the actinides: 234U, 235U, 237Np and 238Np. The experiment is led at the heavy-ion accelerator GSI in Darmstadt, Germany. This facility provides intense relativistic primary beam of 238U. A fragmentation reaction of the primary beam permits to create a secondary beam of radioactive ions, some of which the fission is studied. The ions of the secondary beam are sorted and identified through the FR-S (Fragment Separator), a high resolution recoil spectrometer which is tuned to select the ions of interest.The selected - fissile - ions then fly further to Cave-C, an experimental area where the fission experiment itself takes place. At the entrance of the cave, the secondary beam is excited by Coulomb interaction when flying through an target; the de-excitation process involves low-energy fission. Both fission fragments fly forward in the laboratory frame, due to the relativistic boost inferred from the fissioning nucleus.A complete recoil spectrometer has been designed and built by the SOFIA collaboration in the path of the fission fragments, around the existing ALADIN magnet. The identification of the fragments is performed by means of energy loss, time of flight and deviation in the magnet measurements. Both fission fragments are fully (in mass and charge) and simultaneously identified.This document reports on the analysis performed for (1) the identification of the fissioning system, (2) the identification of both fission fragments, on an event-by-event basis, and (3) the extraction of fission observables: yields, TKE, total prompt neutron multiplicity. These results, concerning the actinides, are discussed, and the

  3. 230Th/ 234U/ 238U and 231Pa/ 235U ages from a single fossil coral fragment by multi-collector magnetic-sector inductively coupled plasma mass spectrometry

    Mortlock, Richard A.; Fairbanks, Richard G.; Chiu, Tzu-chien; Rubenstone, James

    2005-02-01

    The 230Th/ 234U/ 238U age dating of corals via alpha counting or mass spectrometry has significantly contributed to our understanding of sea level, radiocarbon calibration, rates of ocean and climate change, and timing of El Nino, among many applications. Age dating of corals by mass spectrometry is remarkably precise, but many samples exposed to freshwater yield inaccurate ages. The first indication of open-system 230Th/ 234U/ 238U ages is elevated 234U/ 238U initial values, very common in samples older than 100,000 yr. For samples younger than 100,000 yr that have 234U/ 238U initial values close to seawater, there is a need for age validation. Redundant 230Th/ 234U/ 238U and 231Pa/ 235U ages in a single fossil coral fragment are possible by Multi-Collector Magnetic Sector Inductively Coupled Plasma Mass Spectrometry (MC-MS-ICPMS) and standard anion exchange column chemistry, modified to permit the separation of uranium, thorium, and protactinium isotopes from a single solution. A high-efficiency nebulizer employed for sample introduction permits the determination of both 230Th/ 234U/ 238U and 231Pa/ 235U ages in fragments as small as 500 mg. We have obtained excellent agreement between 230Th/ 234U/ 238U and 231Pa/ 235U ages in Barbados corals (30 ka) and suggest that the methods described in this paper can be used to test the 230Th/ 234U/ 238U age accuracy. Separate fractions of U, Th, and Pa are measured by employing a multi-dynamic procedure, whereby 238U is measured on a Faraday cup simultaneously with all minor isotopes measured with a Daly ion counting detector. The multi-dynamic procedure also permits correcting for both the Daly to Faraday gain and for mass discrimination during sample analyses. The analytical precision of 230Th/ 234U/ 238U and 231Pa/ 235U dates is generally better than ±0.3% and ±1.5%, respectively (2 Relative Standard deviation [RSD]). Additional errors resulting from uncertainties in the decay constant for 231Pa and from undetermined

  4. 90Sr, 238U, 234U, 137Cs, 40K and 239/240Pu in Emmental type cheese produced in different regions of Western Europe

    A method is presented for the determination of 90Sr and uranium in Emmental type cheese collected in dairy plants from different European countries. Results display a significant correlation (r=0.708, Student t-test=6.02) between the 90Sr content of the cheese and the altitude of grazing. The highest 90Sr activity is 1.13 Bq kg-1 of cheese and the lowest is 0.29 Bq kg-1. Uranium activity is very low with a highest 238U value of 27 mBq kg-1. In addition, 234U/238U ratio shows a large enrichment in 234U for every location. Without any significant indication of the geographic origin of the cheese, this enrichment is believed to be due to the geological features of the pasture, soil and underground water. These results tend to prove that the contamination of milk by uranium originates principally from the water that the cows drink instead of the forage. This finding may have a great importance in models dealing with dairy food contamination by radionuclides following a nuclear accident. Also, the 90Sr content and to a lesser extent the 234U/238U ratio could be used to trace the authenticity of the origin of the cheese. 137Cs activity is lower than the detection limit of 0.1 Bq kg-1 in all the samples collected (n=20). Based on natural 40K activity in cheese (15-21 Bq kg-1), the decontamination factor for the alkaline cations from milk to cheese is about 20. Plutonium activity stays below the detection limit of 0.3 mBq kg-1

  5. Contribution of 238U-234U-230Th to the mineralogical and geochemical study of alteration profiles. The case of two African lateritic profiles

    In weathering profiles, water-rock interactions generate chemical fluxes from continents to oceans, as dissolved elements or particles. Laterites cover one third of the continents' surface and their formation processes are discussed. It is proposed to study such profiles to decipher their formation and evolution and to recognize the active weathering processes affecting them. Whole rock samples were analysed as well as fine clay fractions (238U-234U-230Th disequilibria in characterising recent mobilities were particularly considered. Two laterites were studied: a ferri-crete from Burkina Faso, and a latosol from Cameroon. The superposed petrographical horizons of lateritic profiles derive from different weathering conditions of the bedrock, and not from a continuous and progressive weathering process. The autochthonous formation of the ferruginous caps is evidenced by mineralogical and geochemical arguments. Remobilization and redistribution of chemical elements occur during the evolution of the profiles, as shown by the lanthanide distribution, which also modifies the signature of long period isotopic systems. Recent, or present, chemical mobilities affect the whole profiles, as evidenced by the 238U-234U-230Th disequilibria. The characteristics of U mobilization processes can be evaluated by use of radioactive decay equations for simple systems affected by a single U mobilization process and then evolving as closed systems. In the case of open systems affected by both U leaching and U input, an appropriate modelling allow to estimate the characteristics of U mobilities (flux, variations). The 238U-234U-230Th disequilibria are useful to detect and characterise the recent chemical mobilities affecting the weathering profiles. It appears that several processes presently affect each horizon of the lateritic profiles, and thus participate to the exported chemical fluxes. (author)

  6. Identification of groundwater recharge sources by using excess 234U and 34S for the arid Ejina-Badain Jaran Interior Basin of Alxa Plateau, inner Mongolia

    The Ejina-Badain Jaran depression of the Alxa Plateau of Inner Mongolia covers an area of 81,380 km2 with annual mean precipitation of about 50 to 80 mm. It is composed of Gobi, Badain Jaran Shamo (Dune Desert) and two grasslands, Gurinai and Wendu Golei. The intermittent Black River ends into lakes in this depression. Precipitation, surface water and ground water from dug wells, boreholes and springs were sampled. Big variations of U, 234Uex, 34Ssulphate and 18O, T, 14C of waters were found especially that of U and 234Uex with ranges of 0.06 ppb to 1455 ppb and -0.408 eU to 13.91 eU respectively. It leads to the differentiation of groundwaters into groups as Gobi, Shamo and the grasslands. The 34Ssulphate was also used for this purpose due to the sulphate in this huge nomads area is mainly the naturally sourced. The recharge sources of groundwaters were identified by using end members with special reference to the Gurinai grassland. Three source waters of its phreatic ground water are: the local precipitation, the Gobi groundwater and the leakage from deep aquifers. Three source waters of deep groundwater are: the Gobi groundwater, the deep groundwater from Shamo and, the palacowater. These recharge sources were checked by other isotopic relationships especially that of 34Ssulphate . The Gobi water appears the mixing of local precipitation, deep percolation from the Black River and, the deep groundwater from different areas including that from Mongolia. From data of all the sampling sites distributed in Gurinai, an areal averaged contribution of every source water for both the phreatic and deep groundwaters were estimated by using U and 234Uex . (author)

  7. Daily intake of /sup 234,235,238/U, /sup 228,230,232/Th and /sup 226,228/Ra by New York City residents

    The daily intake of long-lived alpha-emitting members of the U, Th and Ac series by New York City residents has been estimated from measurements of diet, water and air samples. The total daily intakes from inhalation, food and water consumption in mBq are 18 (234U), 0.7 (235U), 16 (238U), 6 (230Th), 4 (232Th) and 52 (226Ra). From this, we infer that the total daily intakes of 228Th and 228Ra are 4 and 35 mBq, respectively

  8. Accurate measurements of fission-fragment yields in 234,235,236,238U(γ,f) with the SOFIA set-up

    Chatillon, A.; Taïeb, J.; Martin, J.-F.; Pellereau, E.; Boutoux, G.; Gorbinet, T.; Grente, L.; Bélier, G.; Laurent, B.; Alvarez-Pol, H.; Ayyad, Y.; Benlliure, J.; Caamaño, M.; Audouin, L.; Casarejos, E.; Cortina-Gil, D.; Farget, F.; Fernández-Domínguez, B.; Heinz, A.; Jurado, B.; Kelić-Heil, A.; Kurz, N.; Lindberg, S.; Löher, B.; Nociforo, C.; Paradela, C.; Pietri, S.; Ramos, D.; Rodriguez-Sanchez, J.-L.; Rodrìguez-Tajes, C.; Rossi, D.; Schmidt, K.-H.; Simon, H.; Tassan-Got, L.; Törnqvist, H.; Vargas, J.; Voss, B.; Weick, H.; Yan, Y.

    2016-03-01

    SOFIA (Studies On Fission with Aladin) is a new experimental set-up dedicated to accurate measurement of fission-fragments isotopic yields. It is located at GSI, the only place to use inverse kinematics at relativistic energies in order to study the (γ,f) electromagnetic-induced fission. The SOFIA set-up is a large-acceptance magnetic spectrometer, which allows to fully identify both fission fragments in coincidence on the whole fission-fragment range. This paper will report on fission yields obtained in 234,235,236,238U(γ,f) reactions.

  9. Study on the radioactivity and soil-to-plant transfer factor of (226)Ra, (234)U and (238)U radionuclides in irrigated farms from the northwestern Saudi Arabia.

    Al-Hamarneh, Ibrahim F; Alkhomashi, N; Almasoud, Fahad I

    2016-08-01

    The present study addresses the soil-to-plant transfer factors (TFs) of (226)Ra, (234)U and (238)U for 13 types of vegetables and agricultural crops planted under semi-arid environment in the northwestern part of Saudi Arabia. Crop plants along with plant-growing soils were collected from selected farms, which are irrigated from the non-renewable Saq aquifer, and investigated for their radioactivity content by means of alpha spectrometry after applying a radiochemical separation procedure. Hence, TF data for plant roots, green parts (stem and leaves) and fruits were calculated and contrasted to those reported in the literature. Substantial differences were observed in the TFs of Ra and U radioisotopes among plant species. In crop fruits, eggplant exhibited the highest uptake of (226)Ra (TF value of 0.11), while beans (0.16) have the highest TF for (234)U and (238)U. The geometric mean TF values indicated that the crop roots tend to accumulate Ra and U about four to six-folds higher than fruits. The relation between TF values and soil concentrations showed a weak correlation. Activity ratios between radionuclides in crop plants indicated the preferential translocation of U in fruits than Ra even though Ra is more available for root uptake. The fruit/root (F/R) ratios obtained for the investigated plants shown that pepper had the smallest F/R ratios (0.07 ± 0.01, 0.12 ± 0.02 and 0.11 ± 0.02 for (226)Ra, (234)U and (238)U, respectively), while the highest F/R ratios were observed in potatoes (0.71 ± 0.15, 0.44 ± 0.10 and 0.40 ± 0.08 for (226)Ra, (234)U and (238)U, respectively). The TF and F/R ratios data of natural radionuclides in the study region can hopefully improve the scientific knowledge for future studies. PMID:27108351

  10. Bioaccumulation of polonium ({sup 210}Po) and uranium ({sup 234}U, {sup 238}U) in plants around phosphogypsum waste heap in Wislinka (northern Poland)

    Borylo, A.; Skwarzec, B. [Gdansk Univ. (Poland). Faculty of Chemistry

    2011-07-01

    In the study the activities of polonium {sup 210}Po and uranium {sup 234}U, {sup 238}U in plants, collected near phosphogypsum waste heap in Wis'linka (northern Poland), were determined by using the alpha spectrometry. The obtained results revealed that the concentrations of {sup 210}Po, {sup 234}U, and {sup 238}U in the analyzed plants were differentiated. In the analyzed flora organisms the highest amounts of polonium and uranium were found in ruderal plant samples as well as willow samples (Salix viminalis) from protection zone of phosphogypsum waste heap. The concentrations of {sup 210}Po, {sup 234}U and {sup 238}U in the analyzed plants were higher in roots than in green parts of plants. The higher concentrations of {sup 210}Po and {sup 238}U radionuclides were estimated for hydrophyte (common sedge Carex nigra Reichard), the favourite habitat of which is particularly wet meadow and for plants collected in the vicinity of phosphogypsum waste heap. The major source of polonium and uranium in analyzed plants is root system. The values of {sup 234}U/ {sup 238}U activity ratio in all analyzed plants are closed to one, what indicated that source of uranium in analyzed plants is phosphogypsum. The highest uranium and polonium concentrations were characterized for plants, which are covered with tomentose. The comparability polonium and uranium contents were confirmed in edible plants, but higher accumulation was determined in ripe species than immature species of vegetables. The higher polonium and uranium concentrations were noticed in green parts of plant, the lower in roots. Polonium concentration in cultivated plants samples was not species diverse. Therefore, the significant source of polonium and uranium in analyzed plants is wet and dry atmospheric falls gathering the soil and air dust from phosphogypsum waste dump. The maximum {sup 210}Po and {sup 238}U radionuclides concentrations were found in green parts of red beet (Beta vulgaris esculenta), the

  11. IRMM-1000a and IRMM-1000b: uranium reference materials certified for the production date based on the 230Th/234U radiochronometer Part II: Certification

    VENCHIARUTTI CELIA; VARGA ZSOLT; Richter, Stephan; Nicholl, Adrian; KRAJKO JUDIT; JAKOPIC Rozle; Mayer, Klaus; AREGBE Yetunde

    2015-01-01

    The IRMM-1000a and IRMM-1000b uranium reference materials, of 20 mg uranium and 50 mg uranium, respectively, were produced by the European Commission Joint Research Centre’s Institute for Reference Materials and Measurements (EC-JRC-IRMM) in collaboration with the Institute for Transuranium Elements (EC-JRC-ITU). They are the first uranium reference materials certified for the production date based on the 230Th/234U radiochronometer, i.e. the date of the last chemical separation of these two ...

  12. Resuspension and particle transport in the Benthic Nepheloid Layer in and near Fram Strait in relation to faunal abundances and 234Th depletion

    Rutgers v. d. Loeff, Michiel; R. Meyer; Rudels, B.; Rachor, Eike

    2002-01-01

    The West Spitsbergen Current, flowing northward through Fram Strait, causes a benthic nepheloid layer (BNL) on the western slope of the Yermak Plateau. This BNL is weaker on the eastern side of the Plateau and absent on the Greenland side of the Fram Strait where the East Greenland Current flows south. In this BNL we find throughout a depletion of 234Th relative to its parent 238U, and we use this to study the particle dynamics in the BNL. The export flux from the ice-covered surface ocean an...

  13. Accurate measurements of fission-fragment yields in 234,235,236,238U(γ,f with the SOFIA set-up

    Chatillon A.

    2016-01-01

    Full Text Available SOFIA (Studies On Fission with Aladin is a new experimental set-up dedicated to accurate measurement of fission-fragments isotopic yields. It is located at GSI, the only place to use inverse kinematics at relativistic energies in order to study the (γ,f electromagnetic-induced fission. The SOFIA set-up is a large-acceptance magnetic spectrometer, which allows to fully identify both fission fragments in coincidence on the whole fission-fragment range. This paper will report on fission yields obtained in 234,235,236,238U(γ,f reactions.

  14. A study on possible use of Urtica dioica (common nettle) plants as uranium (234U, 238U) contamination bioindicator near phosphogypsum stockpile

    The aim of this study was to determine uranium concentrations in common nettle (Urtica dioica) plants and corresponding soils samples which were collected from the area of phosphogypsum stockpile in Wislinka (northern Poland). The uranium concentrations in roots depended on its concentrations in soils. Calculated BCF and TF values showed that soils characteristics and air deposition affect uranium absorption and that different uranium species have different affinities to U. dioica plants. The values of 234U/238U activity ratio indicate natural origin of these radioisotopes in analyzed plants. Uranium concentration in plants roots is negatively weakly correlated with distance from phosphogypsum stockpile. (author)

  15. Sub-barrier resonance fission and its effects on fission fragment properties, exemplified on 234,238U(n,f)

    Oberstedt S.; Hambsch F.-J.; Tudora A.

    2013-01-01

    The correlation between the sub-barrier resonant behaviour of fission crosssection of non-fissile actinides (pre-scission stage) and the visible fluctuations of their fission fragment and prompt neutron data (post-scission stage) around the incident energies of sub-barrier resonances is outlined and supported by quantitative results for two fissioning systems 234,238U(n,f). These quantitative results refer to both stages of the fission process: a) The pre-scission stage including the calculat...

  16. Collective and single-particle excitations in the heavy deformable nuclei 234U, 233U, 231Th, 230Pa and 232Pa

    In this thesis five heavy deformed isotopes from the mass region A≥230, namely 234U, 233U, 231Th, 230Pa and 232Pa, were investigated by means of deuteron-induced neutron transfer reactions. The even-even isotope 234U has been studied with the 4π-γ-spectrometer MINIBALL at the Cologne Tandem accelerator. Excited nuclei in the isotope 234U were produced using the reaction 235U(d,t) at a beam energy of 11 MeV. The target thickness was 3.5 mg/cm2. The analysis of the γγ-coincidence data yielded a reinterpretation of the level scheme in 12 cases. Considering its decay characteristics, the 4+ state at an excitation energy of 1886.7 keV is a potential candidate for a two-phonon vibrational state. The isotopes 233U, 231Th, 230Pa and 232Pa were investigated at the Munich Q3D spectrometer. For each isotope an angular distribution with angles between 5 and 45 were measured. In all four cases the energy of the polarized deuteron beam (vector polarization of 80%) was 22 MeV. As targets 234U (160 μg/cm2), 230Th (140 μg/cm2) and 231Pa (140 μg/cm2) were used. The experimental angular distributions were compared to results of DWBA calculations. For the odd isotope 233U spin and parity for 33 states are assigned and in the other odd isotope 231Th 22 assignments are made. The excitation spectra of the two odd-odd isotopes 230Pa and 232Pa were investigated for the first time. For the isotope 230Pa 63 states below an excitation energy of 1.5 MeV are identified. Based on the new experimental data the Nilsson configuration of the ground state is either 1/2[530]p-5/2[633]n or 1/2[530]p+3/2[631]n. In addition 12 rotational bands are proposed and from this six values for the GM splitting energy are deduced as well as two new values for the Newby shift. In the other odd-odd isotope 232Pa 40 states below an excitation energy of 850 keV are observed and suggestions for the groundstate band and its GM partner are made. From this one GM splitting energy was determined.

  17. Bioaccumulation of the artificial Cs-137 and the natural radionuclides Th-234, Ra-226, and K-40 in the fruit bodies of Basidiomycetes in Greece.

    Kioupi, Vasiliki; Florou, Heleny; Kapsanaki-Gotsi, Evangelia; Gonou-Zagou, Zacharoula

    2016-01-01

    The bioaccumulation of artificial Cs-137 and natural radionuclides Th-234, Ra-226, and K-40 by Basidiomycetes of several species is studied and evaluated in relation to their substratum soils. For this reason, 32 fungal samples, representing 30 species of Basidiomycetes, were collected along with their substratum soil samples, from six selected sampling areas in Greece. The fungal fruit bodies and the soil samples were properly treated and the activity concentrations of the studied radionuclides were measured by gamma spectroscopy. The measured radioactivity levels ranged as follows: Cs-137 from natural radionuclides and Cs-137 is dependent on the species and the functional group of the fungi. Fungi were found to accumulate Th-234 and not U-238. What is more, potential bioindicators for each radionuclide among the 32 species studied could be suggested for each habitat, based on their estimated concentration ratios (CRs). The calculation of the CRs' mean values for each radionuclide revealed a rank in decreasing order for all the species studied. PMID:26330322

  18. Synthesis and Insecticidal Activity of Spinosyns with C9-O-Benzyl Bioisosteres in Place of the 2',3',4'-Tri-O-methyl Rhamnose.

    Oliver, M Paige; Crouse, Gary D; Demeter, David A; Sparks, Thomas C

    2015-06-17

    The spinosyns are fermentation-derived natural products active against a wide range of insect pests. They are structurally complex, consisting of two sugars (forosamine and rhamnose) coupled to a macrocyclic tetracycle. Removal of the rhamnose sugar results in a >100-fold reduction in insecticidal activity. C9-O-benzyl analogues of spinosyn D were synthesized to determine if the 2',3',4'-tri-O-methyl rhamnose moiety could be replaced with a simpler, synthetic bioisostere. Insecticidal activity was evaluated against larvae of Spodoptera exigua (beet armyworm) and Helicoverpa zea (corn earworm). Whereas most analogues were far less active than spinosyn D, a few of the C9-O-benzyl analogues, such as 4-CN, 4-Cl, 2-isopropyl, and 3,5-diOMe, were within 3-15 times the activity of spinosyn D for larvae of S. exigua and H. zea. Thus, although not yet quite as effective, synthetic bioisosteres can substitute for the naturally occurring 2',3',4'-tri-O-methyl rhamnose moiety. PMID:25993441

  19. Seasonal cycles of particle and solute transport processes in nearshore sediments: 222Rn/226Ra and 234Th/238U disequilibrium at a site in Buzzards Bay, MA

    Particle mixing rates and irrigation rates in the sediments of a site in Buzzards Bay, Massachusetts, have been estimated over two nearly full seasonal cycles. Seasonal variability is consistent with biologically driven transport mechanisms. 234Th/238U disequilibrium measurements were used to estimate particle mixing rates, a cold-season average rate of 5.6 cm2/yr and a warm-season average rate of 17 cm2/yr were found. Excess 234Th inventories in the upper 5 cm of the sediments also varied seasonally, with a cold-season average value of 1.8 dmp/cm2, and a warm-season value of 3.4 dpm/cm2. 222Rn/226Ra disequilibrium in sediment pore waters was used to estimate sediment irrigation. Three seasonal groupings of results were made: (1) December through March, when 222Rn deficits could be explained by vertical molecular diffusion alone, (2) early summer (June), when irrigation was important to at least 20 cm, (3) early fall, when irrigation was important to about 10 cm. A nonlocal exchange/vertical molecular diffusion model (Emerson et al., 1984) was used to obtain quantitative estimates of irrigation rates; model Rn deficit profiles could be fitted to measured profiles quite well. (author)

  20. Determination of the neutron fission cross-section for 233Pa from 0.5 to 10 MeV using the transfer reaction 232Th(3He,pf)234Pa

    Neutron induced fission cross-section of 233Pa in the fast neutron energy range from 0.5 to 10 MeV was determined for the first time as a two term product of the fission probability of 234Pa nucleus and the same compound nucleus formation cross-section. The first term was measured with the transfer reaction 232Th(3He,p) 234Pa while the second one was calculated. The tendency of the resulting data to agree with the existing evaluated one, is a proof for the validity of the utilised method. (author)

  1. Reliability discussion of the sea level dating by mollusk shells using 230-Th/ 234-U method related to the site conservation and the radiochemical results

    In order to study the reliability of the sea levels dating by the means of fossil mollusk shells, 47 samples of different specimens sampled from four unconsolidated terraces at north of the Agadir city were analyzed. Specimen, uranium concentration and isotope ratios have been determined for each sample. The obtained results show that the mollusk shell ages are frequently rejuvenated since the post-mortem uranium uptake by their system, which could be continuous or discontinuous. Except for the trend of younger ages for the high uranium concentration (> 3 ppm) and high 234-U/ 238-U activity ratios (>= 1.2), the radiochemical results of the 47 analyzed samples have not permit to establish obvious methodological criterions which could be used to validate the measured age before confronting it to the stratum geological context which release the mollusk shell. 7 figs., 1 tabs.,18 refs. (au)

  2. IRMM-1000a and IRMM-1000b. Uranium reference materials certified for the production date based on the 230Th/234U radiochronometer. Part II. Certification

    The IRMM-1000a and IRMM-1000b uranium reference materials, of 20 and 50 mg uranium, respectively, were produced by the European Commission Joint Research Centre's Institute for Reference Materials and Measurements (EC-JRC-IRMM) in collaboration with the Institute for Transuranium Elements (EC-JRC-ITU). They are novel uranium reference materials certified for the production date based on the 230Th/234U radiochronometer, i.e. the date of the last chemical separation of these two radionuclides. The certified reference value and its uncertainty, homogeneity and stability of the material were established in accordance with the ISO Guide 34:2009 and the 'Guide to the Expression of Uncertainty in Measurement'. (author)

  3. Revised vibrational band assignments for the experimental IR and Raman spectra of 2,3,4-trifluorobenzonitrile based on ab initio, DFT and normal coordinate calculations

    Hiremath, C. S.; Kalkoti, G. B.; Aralakkanavar, M. K.

    2009-09-01

    In the present study, a systematic vibrational spectroscopic investigation for the experimental IR and Raman spectra of 2,3,4-trifluorobenzonitrile (TFB), aided by electronic structure calculations has been carried out. The electronic structure calculations - ab initio (RHF) and hybrid density functional methods (B3LYP) - have been performed with 6-31G* basis set. Molecular equilibrium geometries, electronic energies, IR intensities, harmonic vibrational frequencies, depolarization ratios and Raman activities have been computed. The results of the calculations have been used to simulate IR and Raman spectra for TFB that showed excellent agreement with the observed spectra. Potential energy distribution (PED) and normal mode analysis have also been performed. The assignments proposed based on the experimental IR and Raman spectra have been reviewed. A complete assignment of the observed spectra has been proposed.

  4. The dietary intake of 238U, 234U, 230Th, 232Th, 228Th and 226Ra from food and drinking water by inhabitants of the Walbrzych region

    Intake with food and water of the natural radionuclides of the uranium and thorium series was determined for adult population of the south-western region in Poland, where in the 1950-ies an exploration of uranium ore was conducted. Concentration of the radionuclides was determined in food products and drinking water and their annual intake was estimated on the basis of the average annual consumption. The intake of 238U, 234U and 230Th occurred mainly with water (33% to 68%), whereas the intake of 232Th, 228Th and 226Ra was mainly with vegetables, potatoes, milk and flour. From the intake and dose coefficients the annual effective doses from the ingested radionuclides were calculated. The total dose was 5.6μSv, of which 74% originated from 226Ra. (author)

  5. Daily intakes of 238U, 234U, 232Th, 230Th, 228Th and 226Ra in the adult population of central Poland

    Activity concentration of the uranium and thorium series radionuclides was determined in foodstuffs and drinking water in central Poland. Annual and daily intake for the adult population was estimated from the concentrations determined and average annual consumption of food and water. The daily intakes (in mBq) were 22.1 (238U), 26.5 (234U), 2.38 (232Th), 4.06 (230Th), 11.2 (228Th) and 42.2 (226Ra). The intake of uranium isotopes occurred mainly with water; the main intake of thorium isotopes was with animal products, vegetables, cereals and potatoes, whereas 226Ra entered mainly with animal products, cereals and vegetables. From the intake and dose coefficients, the annual effective doses for the ingested radionuclides were calculated. The annual effective dose was 5.95 μSv, of which 72.4% originated from 226Ra

  6. Realization of the Temperature Scale in the Range from 234.3 K (Hg Triple Point) to 1084.62°C (Cu Freezing Point) in Croatia

    Zvizdic, Davor; Veliki, Tomislav; Grgec Bermanec, Lovorka

    2008-06-01

    This article describes the realization of the International Temperature Scale in the range from 234.3 K (mercury triple point) to 1084.62°C (copper freezing point) at the Laboratory for Process Measurement (LPM), Faculty of Mechanical Engineering and Naval Architecture (FSB), University of Zagreb. The system for the realization of the ITS-90 consists of the sealed fixed-point cells (mercury triple point, water triple point and gallium melting point) and the apparatus designed for the optimal realization of open fixed-point cells which include the gallium melting point, tin freezing point, zinc freezing point, aluminum freezing point, and copper freezing point. The maintenance of the open fixed-point cells is described, including the system for filling the cells with pure argon and for maintaining the pressure during the realization.

  7. Widely tunable and monochromatic terahertz difference frequency generation with organic crystal 2-(3-(4-hydroxystyryl)-5,5-dime-thylcyclohex-2-enylidene) malononitrile

    Liu, Pengxiang [The Institute of Laser and Optoelectronics, College of Precision Instruments and Opto-electronics Engineering, Tianjin University, Tianjin 300072 (China); The Key Laboratory of Weak-Light Nonlinear Photonics, Ministry of Education, School of Physics and TEDA Applied Physics Institute, Nankai University, Tianjin 300071 (China); Zhang, Xinyuan [Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Yan, Chao; Xu, Degang, E-mail: xudegang@tju.edu.cn; Shi, Wei; Yao, Jianquan [The Institute of Laser and Optoelectronics, College of Precision Instruments and Opto-electronics Engineering, Tianjin University, Tianjin 300072 (China); Li, Yin; Zhang, Guochun; Wu, Yicheng [Beijing Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Zhang, Xinzheng [The Key Laboratory of Weak-Light Nonlinear Photonics, Ministry of Education, School of Physics and TEDA Applied Physics Institute, Nankai University, Tianjin 300071 (China)

    2016-01-04

    We report an experimental study on widely tunable terahertz (THz) wave difference frequency generation (DFG) with hydrogen-bonded crystals 2-(3-(4-hydroxystyryl)-5,5-dime-thylcyclohex-2-enylidene) malononitrile (OH1). The organic crystals were pumped by a ∼1.3 μm double-pass KTiOPO{sub 4} optical parametric oscillator. A tuning range of 0.02–20 THz was achieved. OH1 crystals offer a long effective interaction length (also high output) for the generation below 3 THz, owing to the low absorption and favorable phase-matching. The highest energy of 507 nJ/pulse was generated at 1.92 THz with a 1.89-mm-thick crystal. Comprehensive explanations were provided, on the basis of theoretical calculations. Cascading phenomenon during the DFG process was demonstrated. The photon conversion efficiency could reach 2.9%.

  8. Daily intakes of 238U, 234U, 232Th, 230Th, 228Th and 226Ra in the adult population of central Poland

    Pietrzak-Flis, Z.; Rosiak, L.; Suplinska, M.M.; Chrzanowski, E.; Dembinska, S. [Central Laboratory for Radiological Protection, Konwaliowa 7, 03-194 Warsaw (Poland)

    2001-06-12

    Activity concentration of the uranium and thorium series radionuclides was determined in foodstuffs and drinking water in central Poland. Annual and daily intake for the adult population was estimated from the concentrations determined and average annual consumption of food and water. The daily intakes (in mBq) were 22.1 (238U), 26.5 (234U), 2.38 (232Th), 4.06 (230Th), 11.2 (228Th) and 42.2 (226Ra). The intake of uranium isotopes occurred mainly with water; the main intake of thorium isotopes was with animal products, vegetables, cereals and potatoes, whereas 226Ra entered mainly with animal products, cereals and vegetables. From the intake and dose coefficients, the annual effective doses for the ingested radionuclides were calculated. The annual effective dose was 5.95 {mu}Sv, of which 72.4% originated from 226Ra.

  9. Direct uranium quantitative detection in high precision γ-logging by 1.001 MeV 234mPa γ-ray

    Uranium detection from natural y-ray logging is an indirect method, because the uranium content must be corrected for influence factors from uranium-radium balance and radon escaping. In this article, relationship of the natural radio-nuclides and their characteristic gamma-rays is analyzed. A direct uranium quantitative detection method is proposed, based on high-precision γ-logging and the photoelectric-peak (or energy-window) from 234mPa γ-ray of 1.001 MeV. In standard-model well experiments using a γ-spectrum logging instrument developed in our laboratory, and a LaBr3(Ce) detector, feasibility of this new method is verified. (authors)

  10. Allelic imbalance and cytogenetic deletion of 1p in colorectal adenomas: a target region identified between DIS199 and DIS234

    Bomme, L; Heim, S; Bardi, G;

    1998-01-01

    Both cytogenetic and molecular genetic analyses have shown that many colorectal adenomas carry an acquired deletion distally in the short arm of one chromosome 1, but the two methods have never been brought to bear on the same tumors. The major part of this study was the analysis of 53 previously...... short-term cultured and karyotyped colorectal adenomas for allelic imbalance at eight microsatellite loci in 1p. Allelic imbalances were detected in seven of the 12 adenomas that had cytogenetically visible abnormalities of chromosome 1, as well as in four adenomas that either had a normal karyotype...... (one case) or had clonal chromosome abnormalities that did not seem to involve chromosome 1 (three cases); i.e., 30% of the adenomas had abnormalities involving 1p by the combined approach. A minimal region of overlap seemed to map to between DIS199 and DIS234, suggesting that this is a relevant target...

  11. Widely tunable and monochromatic terahertz difference frequency generation with organic crystal 2-(3-(4-hydroxystyryl)-5,5-dime-thylcyclohex-2-enylidene) malononitrile

    We report an experimental study on widely tunable terahertz (THz) wave difference frequency generation (DFG) with hydrogen-bonded crystals 2-(3-(4-hydroxystyryl)-5,5-dime-thylcyclohex-2-enylidene) malononitrile (OH1). The organic crystals were pumped by a ∼1.3 μm double-pass KTiOPO4 optical parametric oscillator. A tuning range of 0.02–20 THz was achieved. OH1 crystals offer a long effective interaction length (also high output) for the generation below 3 THz, owing to the low absorption and favorable phase-matching. The highest energy of 507 nJ/pulse was generated at 1.92 THz with a 1.89-mm-thick crystal. Comprehensive explanations were provided, on the basis of theoretical calculations. Cascading phenomenon during the DFG process was demonstrated. The photon conversion efficiency could reach 2.9%

  12. Tracing uranium mobility if mesozoic formations on the site of Bure based of radioactive disequilibria (234U/238U): survey/modelling

    Within the frame of investigations performed by the French national agency for the management of radioactive wastes (ANDRA, Agence nationale pour la gestion des dechets radioactifs) in the Eastern part of the Parisian Basin in order to assess the feasibility of a radioactive waste storage in deep geological formations, the authors characterized the mobility of natural radionuclides in the target clayey formation and in its surrounding carbonated formations. The original aims were to determine the radioactive equilibrium or disequilibrium state 234U/238U in the deep formations where the experimental laboratory has been located, to characterize the processes responsible of the observed radioactive disequilibria, and then to determine the chronological implications regarding the chemical stability of these formations

  13. Functional analysis of NopM, a novel E3 ubiquitin ligase (NEL domain effector of Rhizobium sp. strain NGR234.

    Da-Wei Xin

    Full Text Available Type 3 effector proteins secreted via the bacterial type 3 secretion system (T3SS are not only virulence factors of pathogenic bacteria, but also influence symbiotic interactions between nitrogen-fixing nodule bacteria (rhizobia and leguminous host plants. In this study, we characterized NopM (nodulation outer protein M of Rhizobium sp. strain NGR234, which shows sequence similarities with novel E3 ubiquitin ligase (NEL domain effectors from the human pathogens Shigella flexneri and Salomonella enterica. NopM expressed in Escherichia coli, but not the non-functional mutant protein NopM-C338A, showed E3 ubiquitin ligase activity in vitro. In vivo, NopM, but not inactive NopM-C338A, promoted nodulation of the host plant Lablab purpureus by NGR234. When NopM was expressed in yeast, it inhibited mating pheromone signaling, a mitogen-activated protein (MAP kinase pathway. When expressed in the plant Nicotiana benthamiana, NopM inhibited one part of the plant's defense response, as shown by a reduced production of reactive oxygen species (ROS in response to the flagellin peptide flg22, whereas it stimulated another part, namely the induction of defense genes. In summary, our data indicate the potential for NopM as a functional NEL domain E3 ubiquitin ligase. Our findings that NopM dampened the flg22-induced ROS burst in N. benthamiana but promoted defense gene induction are consistent with the concept that pattern-triggered immunity is split in two separate signaling branches, one leading to ROS production and the other to defense gene induction.

  14. Application of 234U/238U activity ratios to investigations of subterranean groundwater discharge in the Cádiz coastal area (SW Spain)

    The activity ratios of 234U/238U were used to investigate processes of subterranean groundwater discharge into coastal marine waters in a study location at Bay of Cádiz (southwest Spain). Marine waters in the bay and surrounding open ocean exhibited U concentrations of 3.4 ± 0.1 μg/L and activity ratios of 1.15 ± 0.01, in agreement with the expected composition of seawater (234U/238U activity ratio = 1.148 ± 0.002). Three water samples obtained from the discharge zone of the Guadalete River exhibited activity ratios of 1.17–1.22 along with slightly lower U concentrations compared to seawater, which is likely due to mixing between seawater and a groundwater end-member. One possible source of groundwater was characterized by sampling and analyzing a well water sample collected in the neighboring village of El Puerto de Santa María; this water sample exhibited an activity ratio of 1.34 ± 0.03 and a U concentration of 1.22 μg/L. Water from the Guadelete River estuarine zone can be explained to result from a two-component mixture of seawater and groundwater from the El Puerto de Santa María well; however, if there are several groundwater reservoirs with different U activity ratios that discharge to the coastal water, then, it may be difficult and more studies are being conducted to address this issue. - Highlights: • The U concentrations are very similar to those expected for average seawater, though in wells closest to the coast are evident lower. • There is some evidence of the existence of submarine groundwater discharge (SGD) based on the obtained values of U concentrations and U ratios. • This methodology could be applied to others study areas within the region and obtain an overview of the movements of water masses in the zone as a hole

  15. 234U/238U isotope ratios in groundwater from Southern Nevada: a comparison of alpha counting and magnetic sector ICP-MS.

    Cizdziel, James; Farmer, Dennis; Hodge, Vernon; Lindley, Kazumasa; Stetzenbach, Klaus

    2005-11-01

    The 234U/238U activity ratio (AR) is extensively used as a geochemical tool to investigate movement and flow relationships in major hydrological units, information that is particularly important when considering nuclear waste disposal. It is usually determined by radiochemical separation and concentration of U, followed by energy-specific alpha particle counting. Alternatively, sector field inductively coupled plasma mass spectrometry (SF-ICP-MS) can be used to measure U isotopic signatures directly in groundwater samples. Here, we compare the two methods for samples of spring and groundwater from southern Nevada. Results for samples stripped from stainless steel disks, previously used for alpha counting, and for splits of groundwater samples show good agreement between the methods. However, SF-ICP-MS is faster, requires much less sample, and produces essentially no waste. We demonstrate applicability of the SF-ICP-MS method for groundwater collected from over 25 wells on and near the Nevada Test Site during 2003. Uranium concentrations ranged from 0.17 to 9.87 ppb with a mean of 2.9 ppb, while 234U/238U AR values ranged from 1.9 to 11.5 with a mean of 4.3. Groundwater collected from deep wells in the northern part of the study area tended to have moderate to high U concentrations and AR values, possibly representative of older volcanic-type waters, whereas groundwater from wells in the Fortymile Wash area had relatively low AR and U concentrations, suggesting younger waters with a possible local recharge component. PMID:16227084

  16. A statistical study of 238U and 234U/238U distributions in coral samples from the Egyptian shoreline of the north-western Red sea and in fossil mollusk shells from the Atlantic coast of High Atlas in Morocco: implications for 230Th/234U dating

    In this work, radiochemical analysis results of 126 uncrystallized coral samples from the Egyptian shoreline of northwestern Red Sea and 120 fossil mollusk shell samples from the Atlantic coast of Moroccan High Atlas at the North of Agadir City in Morocco are presented and discussed. The coral samples were collected in Egypt from the emerged coral reef terraces over 500 km from The Ras Gharib-Ras Shukeir depression (28 10') in the north to Wadi Lahami (north of Ras Banas, 24 10') in the south. The fossil mollusk shells were collected in Morocco from Agadir-Harbour in the south to Tamri village in the north extending over about 50 km. The statistical distributions of results (238U content, 234U/238U activity ratio and ages) obtained on the dated materials in the two different regions were compared for three fossil sea levels corresponding to three different climatic stages (Holocene, 5e, 7 and/or 9) in the aim to establish methodological criteria for judging validity of the measured ages. For corals, 238U content varies in narrow interval around the same average value of 3 ppm for the three sea levels, the calculated initial 234U/238U values are in agreement with the actual sea water ratio (1.15) with some values slightly higher than for the older sea levels. The obtained ages are in good agreement with the ages reported previously for the three emerged fossil sea levels on unrecrystallized corals by alpha spectrometry and by mass spectrometry. For mollusk shells, except for Holocene sea level, 238U and initial 234U/238U activity ratios vary for the older levels in wide intervals, independent of species and calcite contents of samples. The high 238U contents and 234U/238U activity ratio are due eventually to a post-incorporation of secondary uranium from sea water or from continental waters drained away rivers. This incorporation leads to a rejuvenation of mollusk shell ages and is responsible for the wide dispersion of their apparent ages according to the mode and

  17. Temporal evolution of natural radionuclides distributions {sup 238}U, {sup 234}Th, {sup 226}Ra, {sup 228}Ra, {sup 210}Pb and {sup 210}Po in the Bransfield strait, Antarctica peninsula; Evolucao temporal das distribuicoes dos radionuclideos naturais {sup 238}U, {sup 234}Th, {sup 226}Ra, {sup 228}Ra, {sup 210}Pb and {sup 210}Po no estreito de Bransfiel, peninsula Antartica

    Lapa, Flavia Valverde

    2013-07-01

    Research on the distribution of natural radionuclides in Antarctica is rare and thus, there is great interest in to know their occurrence and factors related to its mobilization, transference and accumulation in this extremely fragile environment. Natural radionuclides have been used intensively as tracers in the ocean, helping to better understand processes as sinking and particle resuspension, water masses mixture and oceanic circulation. {sup 234}Th (t½ = 24.1 days) is a particle-reactive radionuclide produced continuously in seawater by the decay of its soluble precursor conservative with salinity {sup 238}U (t½ = 4.5 10{sup 9} years). Since {sup 234}Th presents relatively short half-life, it is used to quantify processes that occur in temporal scale varying from days to weeks. The disequilibrium {sup 234}Th/{sup 238}U in the surface ocean has been applied to estimate carbon fluxes exported via sinking material. The flux of particles biologically productive out of the euphotic zone in the Southern Ocean has special attention due to its importance in the control of CO{sub 2} atmospheric concentrations. The radionuclides {sup 210}Pb (t½ = 22.3 years) and {sup 210}Po (t½ = 138 days) are also particle-reactive. The disequilibrium {sup 210}Po/{sup 210}Pb has been used to estimate fluxes of particles exported in the ocean in the time scale of weeks. The long-lived Ra isotopes, {sup 226}Ra (t½ = 1,600 years) and {sup 228}Ra (t½ = 5.75 years) are soluble in seawater, presenting unique properties that make them excellent tracers of water masses. This research work had the aim to study the distributions of natural radionuclides {sup 238}U, {sup 234}Th, {sup 22}'6Ra, {sup 22}'8Ra, {sup 210}Pb and {sup 210}Po in the Bransfield Strait during 2 samplings carried out in the 2011 Austral Summer (OPERANTAR XXIX and XXX). (author)

  18. Origin and geochemical behavior of uranium in marine sediments. Utilization of the {sup 234}U/{sup 238}U ratio in marine geochemistry; Origine et comportement geochimique de l`uranium dans les sediments marins. Utilisation du rapport ({sup 234}U/{sup 238}U) en geochimie marine

    Organo, Catherine [Paris-11 Univ., 91 - Orsay (France)

    1997-01-20

    The first part of this thesis presents the current situation of knowledge of uranium in marine environment. The second part describes the methods of analysis as well as the material support of the study, i.e., the sediments and marine deposits investigated. The third part is dedicated to the study of uranium mobility in marine sediments characterized by detrital terrigenous composition (pelagic clays). This approach allowed quantifying the entering and leaving flux of uranium after the sediment settling and, to discuss, on this basis, the consequences on the uranium oceanic balance. In the third part the origin and behavior of uranium in zones of high surface productivity is studied. The uranium enrichments observed in the hemi-pelagic sediments of the EUMELI (J.G.O.F.S.-France) programme will constitute a material of study adequate for measuring the variations in the {sup 234}U/2{sup 38U} ratio in solid phase, in response to the oxido-reducing characteristics of the sediment. Thus establishing the origin of the trapped uranium has been possible. Also, the nature of the sedimentary phases related to uranium in bio-genetic sediments in the Austral Ocean was determined. Thus a relationship between the variations in the {sup 234}U/{sup 238} and the diagenetic transformations was possible to establish. Finally in the fifth part a study of the behavior of uranium in a polymetallic shell characteristic for deposits of hydrogenized origin 146 refs., 57 figs., 23 tabs.

  19. Measurement of the neutron capture cross section of U{sup 234} in n-TOF at CERN for Generation IV nuclear reactors; Mesure de la section efficace de capture neutronique de l'{sup 234}U a n-TOF au CERN pour les reacteurs nucleaires de generation 4

    Dridi, W

    2006-11-15

    Accurate and reliable neutron capture cross sections are needed in many research areas, including stellar nucleosynthesis, advanced nuclear fuel cycles, waste transmutation, and other applied programs. In particular, the accurate knowledge of U{sup 234}(n,{gamma}) reaction cross section is required for the design and realization of nuclear power plants based on the thorium fuel cycle. We have measured the neutron capture cross section of U{sup 234}, with a 4{pi} BaF{sub 2} Total Absorption Calorimeter, at the recently constructed neutron time-of-flight facility n-TOF at CERN in the energy range from 0.03 eV to 1 MeV. Monte-Carlo simulations with GEANT4 and MCNPX of the detector response have been performed. After the background subtraction and correction with dead time and pile-up, the capture yield from 0.03 eV up to 1.5 keV was derived. The analysis of the capture yield in terms of R-matrix resonance parameters is discussed. We have identified 123 resonances and measured the resonance parameters in the energy range from 0.03 eV to 1.5 keV. The mean radiative width <{gamma}{sub {gamma}}> is found to be (38.2 {+-} 1.5) meV and the mean spacing parameter is (11.0 {+-} 0.2) eV, both values agree well with recommended values.

  20. Sub-barrier resonance fission and its effects on fission fragment properties, exemplified on 234,238U(n,f)

    The correlation between the sub-barrier resonant behaviour of fission cross-section of non-fissile actinides (pre-scission stage) and the visible fluctuations of their fission fragment and prompt neutron data (post-scission stage) around the incident energies of sub-barrier resonances is outlined and supported by quantitative results for two fissioning systems 234,238U(n,f). These quantitative results refer to both stages of the fission process: a) the pre-scission stage including the calculation of neutron induced cross-sections with focus on fission. Calculations are done in the frame of the refined statistical model for fission with sub-barrier effects also extended to take into account the multi-modal fission; b) the post-scission stage including the prompt neutron emission treated in the frame of the Point-by-Point model. Total quantities characterizing the fission fragments and the prompt neutrons obtained by averaging the Point-by-Point results as a function of fragment over the fission fragment distributions reveal variations around the energies of sub-barrier resonances in the fission cross-section. (authors)

  1. Sub-barrier resonance fission and its effects on fission fragment properties, exemplified on 234,238U(n,f

    Oberstedt S.

    2013-03-01

    Full Text Available The correlation between the sub-barrier resonant behaviour of fission crosssection of non-fissile actinides (pre-scission stage and the visible fluctuations of their fission fragment and prompt neutron data (post-scission stage around the incident energies of sub-barrier resonances is outlined and supported by quantitative results for two fissioning systems 234,238U(n,f. These quantitative results refer to both stages of the fission process: a The pre-scission stage including the calculation of neutron induced cross-sections with focus on fission. Calculations are done in the frame of the refined statistical model for fission with sub-barrier effects also extended to take into account the multi-modal fission. b The post-scission stage including the prompt neutron emission treated in the frame of the Point-by-Point model. Total quantities characterizing the fission fragments and the prompt neutrons obtained by averaging the Point-by-Point results as a function of fragment over the fission fragment distributions reveal variations around the energies of sub-barrier resonances in the fission crosssection.

  2. Molecular level characterization of diatom-associated biopolymers that bind 234Th, 233Pa, 210Pb, and 7Be in seawater: A case study with Phaeodactylum tricornutum

    Chuang, Chia-Ying; Santschi, Peter H.; Xu, Chen; Jiang, Yuelu; Ho, Yi-Fang; Quigg, Antonietta; Guo, Laodong; Hatcher, Patrick G.; Ayranov, Marin; Schumann, Dorothea

    2015-09-01

    In order to investigate the importance of biogenic silica associated biopolymers on the scavenging of radionuclides, the diatom Phaeodactylum tricornutum was incubated together with the radionuclides 234Th, 233Pa, 210Pb, and 7Be during their growth phase. Normalized affinity coefficients were determined for the radionuclides bound with different organic compound classes (i.e., proteins, total carbohydrates, uronic acids) in extracellular (nonattached and attached exopolymeric substances), intracellular (ethylene diamine tetraacetic acid and sodium dodecyl sulfate extractable), and frustule embedded biopolymeric fractions (BF). Results indicated that radionuclides were mostly concentrated in frustule BF. Among three measured organic components, Uronic acids showed the strongest affinities to all tested radionuclides. Confirmed by spectrophotometry and two-dimensional heteronuclear single quantum coherence-nuclear magnetic resonance analyses, the frustule BF were mainly composed of carboxyl-rich, aliphatic-phosphoproteins, which were likely responsible for the strong binding of many of the radionuclides. Results from this study provide evidence for selective absorption of radionuclides with different kinds of diatom-associated biopolymers acting in concert rather than as a single compound. This clearly indicates the importance of these diatom-related biopolymers, especially frustule biopolymers, in the scavenging and fractionation of radionuclides used as particle tracers in the ocean.

  3. Impact of functional monomers, cross-linkers and porogens on morphology and recognition properties of 2-(3,4-dimethoxyphenyl)ethylamine imprinted polymers

    The main objective of this paper was to examined the impact of synthetic reagents on morphology and recognition properties of 2-(3,4-dimethoxyphenyl)ethylamine imprinted polymers. The effect of nine different functional monomers, five porogens and four cross-linkers on the binding capacity of particles was analyzed. The results revealed that the highest imprinting factor (1.81) showed the polymer obtained from methacrylic acid and ethylene glycol dimethacrylate in toluene. The binding capacities of imprinted (MIP1) and non-imprinted (NIP1) materials were 135.3 ± 9.8 and 74.8 ± 7.8 μmol g-1, respectively. The specific surface areas were 55.05 ± 3.89 for MIP1 and 38.72 ± 2.40 m2 g-1 for NIP1. The SEM analysis confirmed that the surface of MIP1 is rougher and denser than NIP1. Structural analysis supported by 13C CP/MAS NMR spectra was also performed. The binding abilities of homoveratrylamine and eight structurally related compounds to MIP1 showed that strong interactions between carboxylic group in the polymer and amine group in the analyte together with its molecular volume govern the recognition mechanism.

  4. Synthesis and antimicrobial activity of some new 2-(3-(4-Aryl-1-phenyl-1H-pyrazol-4-yl chroman-4-ones

    O Prakash

    2011-01-01

    Full Text Available Seven new 2-(3-(4-aryl-1-phenyl-1H-pyrazol-4-yl chroman-4-ones (4a-4g have been synthesized by cyclization of 2-hydroxychalcone analogues of pyrazole 3a-3g using conc. HCl in acetic acid. The structures of the compounds 4a-4g were established by the combined use of 1 HNMR, IR and mass spectra. All the seven compounds were tested in vitro for their antibacterial activity against two Gram positive bacteria namely Staphylococcus aureus and Bacillus subtilis and two Gram negative bacteria Escherichia coli and Pseudomonas aeruginosa. The compounds 4b, 4c, 4e, 4f, 4g have displayed good antibacterial activity when compared with commercially available antibiotic, ciprofloxacin. These compounds also were screened for their antifungal activity against two ear pathogenic fungi, namely Aspergillus Niger and A. flavus. The compounds 4a, 4c, 4d, 4g exhibited good antifungal activity when compared with commercially available antifungal, fluconazole.

  5. EC comparison on the determination of {sup 226}Ra, {sup 228}Ra, {sup 234}U and {sup 238}U in water among European monitoring laboratories

    Waetjen, U., E-mail: uwe.waetjen@ec.europa.e [European Commission, Joint Research Centre, Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440 Geel (Belgium); Benedik, L.; Spasova, Y.; Vasile, M.; Altzitzoglou, T. [European Commission, Joint Research Centre, Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440 Geel (Belgium); Beyermann, M. [Bundesamt fuer Strahlenschutz (BfS), Koepenicker Allee 120-130, D-10318 Berlin (Germany)

    2010-07-15

    In anticipation of new European requirements for monitoring radioactivity concentration in drinking water, IRMM organized an interlaboratory comparison on the determination of low levels of activity concentrations (about 10-100 mBq L{sup -1}) of the naturally occurring radionuclides {sup 226}Ra, {sup 228}Ra, {sup 234}U and {sup 238}U in three commercially available mineral waters. Using two or three different methods with traceability to the International System of Reference (SIR), the reference values of the water samples were determined prior to the proficiency test within combined standard uncertainties of the order of 3%-10%. An overview of radiochemical separation and measurement methods used by the 45 participating laboratories are given. The results of the participants are evaluated versus the reference values. Several of the participants' results deviate by more than a factor of two from the reference values, in particular for the radium isotopes. Such erroneous analysis results may lead to a crucial omission of remedial actions on drinking water supplies or to economic loss by an unjustified action.

  6. Sorption behavior of U(VI), 234U(VI) and 238U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in China

    MIN; Maozhong; LUO; Xingzhang; WANG; Ju; JIN; Yuanxin; WAN

    2005-01-01

    The first results of sorption experiments of U(VI), 234U(VI) and 238U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, China are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in China. The present experimental results show that the maximum U(VI) sorption reached 92% at near-neutral Ph and the distribution coefficient (Kd) was 1226 Ml/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive elements is necessary for HLW deep geological disposal repository. No preferential sorption of 234U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

  7. High resolution measurement of the 234U(n,f) cross section in the neutron energy range from 0.5 eV to 100 keV

    The 234U(n,f) cross section has been measured in the energy range from 0.5 eV to 100 keV at the GELINA neutron time-of flight facility of the Institute for Reference Materials and Measurements in Geel using highly enriched 234U samples. Two independent measurements were performed: one in a low detection geometry (15% of 2 π) and another in a 2 π detection geometry. A235U(n,f) cross-section measurement was performed under the same experimental conditions, allowing a reliable correction for the 235U(n,f) contribution to the yield. Special attention has been given to the strongest resonance at 5.16 eV and to the fission resonance integral If for which large discrepancies are reported in the literature. (authors)

  8. Development of sequential analytical method for the determination of U-238, U-234, Th-232, Th-230, Th-228, Ra-226 and Ra-228 and its application in mineral waters

    A sequential analytical method for the determination of U-238, U-234, Th-232, Th-230, Th-228, Ra-226 and Ra-228 in environmental samples and applied to the analysis of mineral waters is studied. Thorium isotopes are coprecipitated with lanthanium fluoride before counting in alpha spectrometer, the uranium isotopes are determined by alpha spectrometry following extraction with TOPO onto a polymenic membrane. Radium-226 is determined with the radom emanation technique. (M.J.C.)

  9. Determination of the 233Pa(n, f) reaction cross section from 0.5 to 10 MeV neutron energy using the transfer reaction 232Th(3He, p)234Pa

    The fission probability distributions of 232,233,234Pa and 231Th have been measured up to an excitation energy of 15 MeV, using the transfer reactions 232Th(3He, t)232Pa, 232Th(3He, d)233Pa, 232Th(3He, p)234Pa and 232Th(3He, 4He)231Th. From these measurements, the neutron induced fission cross sections of 231Pa, 233Pa and 230Th have been determined from the product of the fission probabilities of 232Pa, 233Pa and 231Th respectively with the calculated compound nucleus formation cross sections in the 231Pa+n, 233Pa+n and 230Th+n reactions. The validity of the applied method has been successfully tested with the existing neutron induced fission cross sections of 230Th and 231Pa. Special emphasis is put on the 233Pa(n, f) reaction which is of importance for thorium fueled nuclear reactors. Based on a statistical model analysis of the neutron induced fission cross section as a function of neutron energy, it has been possible to determine the barrier parameters of the 234Pa fissioning nucleus. Cross sections for the compound nucleus inelastic scattering 233Pa(n, n') and radiative capture 233Pa(n, γ) reactions have also been calculated and compared with recent evaluations

  10. Determination of the 233Pa(n, γ) capture cross section up to neutron energies of 1 MeV using the transfer reaction 232Th(3He, p)234Pa*

    The γ-ray emission probability distribution of 234Pa* has been measured between 5.2 and 6.2 MeV excitation energy using the transfer reaction 232Th(3He, p)234Pa* at an incident 3He energy of 24 MeV. The experimental set-up is made of four liquid scintillator C6D6 detectors and four Si telescopes arranged to detect γ rays and charged particles in coincidence. In order to determine the total number of γ-ray cascades in a given nucleus, the raw experimental detected gamma-ray events have to be corrected by the weighting function technique. This weighting requires complete knowledge of the efficiency and response functions for the C6D6 detector set-up and surroundings. These have been determined experimentally using gamma-ray sources, inelastic scattering reactions and transfer reactions on light nuclei. Simulations which reproduce successfully the detector response and efficiency are presented. From these measurements, the (n, γ) capture cross section of 233Pa, in the neutron energy range 0 to 1 MeV, has been deduced via the product of the measured γ emission probability of 234Pa* with the calculated compound nucleus formation cross section of the reaction 233Pa + n. A comparison between existing data bases or recent predictions and the present results is also made

  11. 234U/238U and δ87Sr in peat as tracers of paleosalinity in the Sacramento-San Joaquin Delta of California, USA

    Drexler, Judith Z.; Paces, James B.; Alpers, Charles N.; Windham-Myers, Lisamarie; Neymark, Leonid; Bullen, Thomas D.; Taylor, Howard E.

    2013-01-01

    The purpose of this study was to determine the history of paleosalinity over the past 6000+ years in the Sacramento-San Joaquin Delta (the Delta), which is the innermost part of the San Francisco Estuary. We used a combination of Sr and U concentrations, d87Sr values, and 234U/238U activity ratios (AR) in peat as proxies for tracking paleosalinity. Peat cores were collected in marshes on Browns Island, Franks Wetland, and Bacon Channel Island in the Delta. Cores were dated using 137Cs, the onset of Pb and Hg contamination from hydraulic gold mining, and 14C. A proof of concept study showed that the dominant emergent macrophyte and major component of peat in the Delta, Schoenoplectus spp., incorporates Sr and U and that the isotopic composition of these elements tracks the ambient water salinity across the Estuary. Concentrations and isotopic compositions of Sr and U in the three main water sources contributing to the Delta (seawater, Sacramento River water, and San Joaquin River water) were used to construct a three-end-member mixing model. Delta paleosalinity was determined by examining variations in the distribution of peat samples through time within the area delineated by the mixing model. The Delta has long been considered a tidal freshwater marsh region, but only peat samples from Franks Wetland and Bacon Channel Island have shown a consistently fresh signal (<0.5 ppt) through time. Therefore, the eastern Delta, which occurs upstream from Bacon Channel Island along the San Joaquin River and its tributaries, has also been fresh for this time period. Over the past 6000+ years, the salinity regime at the western boundary of the Delta (Browns Island) has alternated between fresh and oligohaline (0.5-5 ppt).

  12. 234U/238U - δ7Li - δ11B isotope systematics on aquifer groundwaters from deep scientific boreholes from the Meuse-Haute Marne site. Preliminary results

    Document available in extended abstract form only. Groundwater data have been acquired all around the Underground Research Laboratory, in deep boreholes, to determine the origin and residence time of water circulations in limestones of Oxfordian and Dogger age, surrounding the Callovo-Oxfordian argillites, and to determine the hydrogeologic role of the argillites regarding aquifers. In this work, U, Li and B isotopes have been analyzed in the framework of two research projects funded by BRGM and ANDRA (projects IsoBLiFe and BULiTh). In the Meuse/Haute-Marne area, the Dogger and Oxfordian limestones have a very weak permeability and pass through a free aquifer flow regime in the southeastern part where they join the captive underground aquifer in the centre and Northwest. Most U activity ratios are lower than the secular equilibrium value, especially for Oxfordian waters that may be very depleted in 234U (with activity ratios as low as 0.54), whereas Dogger groundwaters are on average closer to the equilibrium. In addition, U concentrations are generally lower in Dogger groundwaters. For Dogger groundwaters, iso-value (activity) curves follow approximately a NE-SW axis, parallel to both outcropping areas of Dogger limestones (∼ 30-35 km East of the Bure region) and the Gondrecourt Graben. This is compatible with a downflow return-to-equilibrium through time, but the lower activity ratios (close to 0.8) measured West of the Graben (on a Joinville - Commercy line) show that other processes have to be involved to explain U data. These lower activities might result from water-rock interaction processes and/or from an input of waters very depleted in 234U, which would 'contaminate' the Dogger groundwaters. In contrast, U activities measured in Oxfordian groundwaters cannot be explained a priori by any process of downflow return-to-equilibrium, as the recharge zone is located a few km East to the study area. Indeed, U activity iso-value curves follow a

  13. CREATING THE KULTUK POLYGON FOR EARTHQUAKE PREDICTION: VARIATIONS OF (234U/238U AND 87SR/86SR IN GROUNDWATER FROM ACTIVE FAULTS AT THE WESTERN SHORE OF LAKE BAIKAL

    S. V. Rasskazov

    2015-12-01

    Full Text Available Introduction. Determinations of (234U/238U in groundwater samples are used for monitoring current deformations in active faults (parentheses denote activity ratio units. The cyclic equilibrium of activity ratio 234U/238U≈≈(234U/238U≈γ≈1 corresponds to the atomic ratio ≈5.47×10–5. This parameter may vary due to higher contents of 234U nuclide in groundwater as a result of rock deformation. This effect discovered by P.I. Chalov and V.V. Cherdyntsev was described in [Cherdyntsev, 1969, 1973; Chalov, 1975; Chalov et al., 1990; Faure, 1989]. In 1970s and 1980s, only quite laborious methods were available for measuring uranium isotopic ratios. Today it is possible to determine concentrations and isotopic ration of uranium by express analytical techniques using inductively coupled plasma mass spectrometry (ICP‐MS [Halicz et al., 2000; Shen et al., 2002; Cizdziel et al., 2005; Chebykin et al., 2007]. Sets of samples canbe efficiently analysed by ICP‐MS, and regularly collected uranium isotope values can be systematized at a new quality level for the purposes of earthquake prediction. In this study of (234U/238U in groundwater at the Kultuk polygon, we selected stations of the highest sensitivity, which can ensure proper monitoring of the tectonic activity of the Obruchev and Main Sayan faults. These two faults that limit the Sharyzhalgai block of the crystalline basement of the Siberian craton in the south are conjugated in the territory of the Kultuk polygon (Fig 1. Forty sets of samples taken from 27 June 2012 to 28 January 2014 were analysed, and data on 170 samples are discussed in this paper.Methods. Isotope compositions of uranium and strontium were determined by methods described in [Chebykin et al., 2007; Pin et al., 1992] with modifications. Analyses of uranium by ISP‐MS technique were performed using an Agilent 7500ce quadrapole mass spectrometer of the Ultramicroanalysis Collective Use Centre; analyses of

  14. His-234是毛白杨对香豆酸∶CoA连接酶的重要酶催化活性残基%His-234 is an Essential Residue for Populus tomentosa 4-coumarate ∶ CoA Ligase Enzymatic Mechanisms

    任百光; 李德峰; 郑彩霞; 盖颖; 蒋湘宁; 胡永林

    2013-01-01

    对香豆酸∶CoA连接酶(4-coumarate∶ coenzyme A ligase,4CL)是植物苯丙烷类代谢途径中的一个重要的酶.4CL以肉桂酸衍生物(香豆酸、咖啡酸、阿魏酸等)、ATP和CoA为底物合成相应的酰基-CoA酯,这些酰基-CoA酯是一系列重要化合物(如木质素)的前体.4CL的酶催化反应分两步进行:第一步以肉桂酸衍生物和Mg2+-ATP为底物合成酰基-AMP,第二步用CoA取代AMP,产生酰基-CoA酯,催化过程中酶的构象产生明显的变化.因为4CL在木质素的合成中所起的作用,这个酶是通过蛋白质工程方法改进林产品质量的重要靶标.我们通过X射线衍射技术,解析了毛白杨对香豆酸∶CoA连接酶l(Pt4CLl)与其中间产物对香豆酰-AMP的复合物晶体结构,与同家族成员结构比对,确定所获得的蛋白质结构为Pt4CL1催化第二步反应,即酰基-CoA酯合成的构象.结构分析表明:His-234残基在Pt4CL1的酶催化机理中起着多重作用,即通过侧链与AMP磷酸基团形成氢键,降低磷酸基团的负电荷,催化CoA的亲核取代反应;侧链可以采取两种不同的构象以调节CoA进入Pt4CL1的催化中心;His-234的侧链还可能夺取CoA巯基的质子,从而增强CoA的亲核反应活性.突变体酶活数据结果也显示His-234对Pt4CL1的活性非常重要,是Pt4CL1催化中心的活性残基.

  15. {sup 90}Sr, {sup 238}U, {sup 234}U, {sup 137}Cs, {sup 40}K and {sup 239/240}Pu in Emmental type cheese produced in different regions of Western Europe

    Froidevaux, P. E-mail: pascal.froidevaux@inst.hospvd.ch; Geering, J.-J.; Pillonel, L.; Bosset, J.-O.; Valley, J.-F

    2004-07-01

    A method is presented for the determination of {sup 90}Sr and uranium in Emmental type cheese collected in dairy plants from different European countries. Results display a significant correlation (r=0.708, Student t-test=6.02) between the {sup 90}Sr content of the cheese and the altitude of grazing. The highest {sup 90}Sr activity is 1.13 Bq kg{sup -1} of cheese and the lowest is 0.29 Bq kg{sup -1}. Uranium activity is very low with a highest {sup 238}U value of 27 mBq kg{sup -1}. In addition, {sup 234}U/{sup 238}U ratio shows a large enrichment in {sup 234}U for every location. Without any significant indication of the geographic origin of the cheese, this enrichment is believed to be due to the geological features of the pasture, soil and underground water. These results tend to prove that the contamination of milk by uranium originates principally from the water that the cows drink instead of the forage. This finding may have a great importance in models dealing with dairy food contamination by radionuclides following a nuclear accident. Also, the {sup 90}Sr content and to a lesser extent the {sup 234}U/{sup 238}U ratio could be used to trace the authenticity of the origin of the cheese. {sup 137}Cs activity is lower than the detection limit of 0.1 Bq kg{sup -1} in all the samples collected (n=20). Based on natural {sup 40}K activity in cheese (15-21 Bq kg{sup -1}), the decontamination factor for the alkaline cations from milk to cheese is about 20. Plutonium activity stays below the detection limit of 0.3 mBq kg{sup -1}.

  16. Identification of groundwater recharge sources by using of 234U excess and 34S for the arid Ejina-Badain Jaran Interior Basin of Alxa Plateau in Inner Mongolia

    The Ejina-Badain Jaran depression of the Alxa Plateau of Inner Mongolia covers an area of 81,380 km2 with annual mean precipitation of about 50 to 80 mm. It is composed of Gobi, Badain Jaran Shamo (Dune Desert) and two grasslands, Gurinai and Wendu Golei. The intermittent Black River ends into lakes in this depression. Precipitation, surface water, groundwater from dug wells, boreholes and springs are sampled. Big variations of U, 234Uex, 34Ssulphate, 18O, 3H, and 14C of waters are found especially that of U and 234Uex with ranges of 0.06 ppb to 1455 ppb and, - 0.408 eU to 13.91 eU respectively, it leads to the differentiation of groundwaters into groups as Gobi, Shamo and the grasslands. The 34Ssulphate is also used for this purpose due to the sulphate in this huge nomad area. The recharge sources of groundwater are identified by using the end members with special reference to the Gurinai grassland. Three source waters of its phreatic groundwater are: the local precipitation, the Gobi groundwater and the leakage from deep aquifers. Three source waters of deep groundwater are: the Gobi groundwater, the deep groundwater from Shamo and the palaeowater. These recharge sources are checked by other isotopic ratios especially that of 34Ssulphate. The Gobi water appears to be the mixing of local precipitation, deep percolation from the Black River and the deep groundwater from different areas including that from Mongolia. From data of all the sampling sites distributed in Gurinai, an areal averaged contribution of every source water for both the phreatic and deep groundwaters are estimated by using of U and 234Uex. (author)

  17. Obtention of agricultural gypsum traced on 34 S (Ca34 SO4.2H2O), by chemical reaction between H234 SO4 and Ca(OH)2

    The gypsum (CaSO4.2H2O) has double function in the soil: as source of calcium and sulfur and reducing agent of aluminum saturation. The sulfur for the plants has acting in the vital functions and it is proven fact increase of the S deficiency in Brazilian soils. The isotope tracer 34 S can elucidate important aspects in the sulfur cycle. The Ca34 SO4.2H2O was obtained by chemical reaction between Ca(OH)2 and H234 SO4 solution. The acid was obtained by chromatography ionic change, using cationic resin Dowex 50WX8 and Na234 SO4 solution. The reaction was realized under slow agitation. After the reaction, the precipitate was separated and dried in ventilated stove at 60 deg C temperature. The Mass of the Ca34 SO4.2H2O produced was determined by method gravimetric. This way, a system contends resin 426 cm3, considering volume of 2.2 liters can be obtained a solution contends 44.2 g of H234 SO4, theoretically could be produced 78.0 g of Ca34 SO4.2H2O approximately. With results of the tests were verified that there was not total precipitation of the Ca34SO4.2H2O. Were produced 73.7± 0.6 g of Ca34 SO4.2H2O representing average income 94.6±0.8 %. The purity of the produced CaSO4.2H2O was 98%. (author)

  18. Principio de justícia universal : de modelo absoluto a model restrictivo, a propósito de sucesivas modificacions del Art. 23.4 L.O. Poder judicial

    Bonet Esteva, Margarita

    2015-01-01

    Este artículo tiene por objeto exponer la progresión del Principio de Justicia Universal en el ordenamiento español. En primer lugar se ubicará la cuestión en el contexto amplio. Luego se expondrá la historia legislativa del art. 23.4 LOPJ y sus reformas más significativas. Se demostrará como se ha abandonado la concepción absoluta del principio de Justicia universal para derivar hacia un sistema de justicia universal aplicada restrictivamente. Esa aplicación restrictiva se basa en la relevan...

  19. The particulate 7Be/210Pbxs and 234Th/210Pbxs activity ratios as tracers for tidal-to-seasonal particle dynamics in the Gironde estuary (France): implications for the budget of particle-associated contaminants.

    Saari, Hanna-Kaïsa; Schmidt, Sabine; Castaing, Patrice; Blanc, Gérard; Sautour, Benoît; Masson, Olivier; Cochran, J Kirk

    2010-09-15

    The short-lived natural radionuclides (7)Be (T(1/2)=53 days), (234)Th(xs) (T(1/2)=24.1 days) and (210)Pb(xs) (T(1/2)=22.3 years), i.e. (234)Th and (210)Pb in excesses of that supported within particles by the decay of their parent isotopes, were analysed in suspended particulate matter (SPM) to study the particle dynamics in the Gironde fluvial estuarine system (France), strongly impacted by heavy metal pollution. From surveys of this land-ocean interface in 2006 and 2007, we established a times series of these radioisotopes and of their activity ratios ((7)Be/(210)Pb(xs) and (234)Th/(210)Pb(xs) ARs) in particles sampled under different hydrological conditions. The particulate (7)Be/(210)Pb(xs) AR varies along the fluvial estuarine system mainly due to variations in (7)Be activities, controlled by riverine, oceanic and atmospheric inputs and by resuspension of old (7)Be-deficient sediments. These processes vary with river discharge, tidal cycle and season. Therefore, seasonal particle transport processes can be described using variations of the SPM (7)Be/(210)Pb(xs) ARs. During high river discharge, the SPM (7)Be/(210)Pb(x) ARs decrease from river to the ocean. The turbidity maximum zone (TMZ) is dispersed and the particles, and the associated contaminants, are rapidly transported from river to coastal waters, without significant retention within the TMZ. During low river discharge, the TMZ intrudes into the fluvial estuary, and the lowest (7)Be/(210)Pb(x) ARs are observed there due to resuspension of (7)Be-deficient sediments. Away from the TMZ, from the middle to lower estuary, SPM (7)Be/(210)Pb(x) ARs increase, indicating that the particles have been recently tagged with (7)Be. We explain this trend as being caused by marine input of dissolved radionuclides, as traced by SPM (234)Th/(210)Pb(xs) ARs, followed by scavenging in the estuary. This result indicates that particle transport models based on (7)Be and trace-metal budgets must consider oceanic dissolved

  20. Fragment-mass, kinetic energy, and angular distributions for 234U(, ) at incident neutron energies from n = 0.2 MeV to 5.0 MeV

    AL-ADILI ALI; Hambsch, Franz-Josef; Pomp, S.; Oberstedt, Stephan; Vidali, Marzio

    2015-01-01

    This work investigates the neutron-induced fission of 234U and the fission-fragment properties for neutron energies between n = 0.2 MeV and 5.0 MeV with a special highlight on the prominent vibrational resonance at n = 0.77 MeV. Angular-, energy- and mass distributions were determined based on the double-energy (2E) technique by means of a Twin Frisch-Grid Ionization Chamber. The experimental data are parametrized in terms of fission modes based on the Multi-Modal Random Neck-Rupture model...

  1. The particulate 7Be/210Pbxs and 234Th/210Pbxs activity ratios as tracers for tidal-to-seasonal particle dynamics in the Gironde estuary (France): Implications for the budget of particle-associated contaminants

    The short-lived natural radionuclides 7Be (T1/2 = 53 days), 234Thxs (T1/2 = 24.1 days) and 210Pbxs (T1/2 = 22.3 years), i.e. 234Th and 210Pb in excesses of that supported within particles by the decay of their parent isotopes, were analysed in suspended particulate matter (SPM) to study the particle dynamics in the Gironde fluvial estuarine system (France), strongly impacted by heavy metal pollution. From surveys of this land-ocean interface in 2006 and 2007, we established a times series of these radioisotopes and of their activity ratios (7Be/210Pbxs and 234Th/210Pbxs ARs) in particles sampled under different hydrological conditions. The particulate 7Be/210Pbxs AR varies along the fluvial estuarine system mainly due to variations in 7Be activities, controlled by riverine, oceanic and atmospheric inputs and by resuspension of old 7Be-deficient sediments. These processes vary with river discharge, tidal cycle and season. Therefore, seasonal particle transport processes can be described using variations of the SPM 7Be/210Pbxs ARs. During high river discharge, the SPM 7Be/210Pbx ARs decrease from river to the ocean. The turbidity maximum zone (TMZ) is dispersed and the particles, and the associated contaminants, are rapidly transported from river to coastal waters, without significant retention within the TMZ. During low river discharge, the TMZ intrudes into the fluvial estuary, and the lowest 7Be/210Pbx ARs are observed there due to resuspension of 7Be-deficient sediments. Away from the TMZ, from the middle to lower estuary, SPM 7Be/210Pbx ARs increase, indicating that the particles have been recently tagged with 7Be. We explain this trend as being caused by marine input of dissolved radionuclides, as traced by SPM 234Th/210Pbxs ARs, followed by scavenging in the estuary. This result indicates that particle transport models based on 7Be and trace-metal budgets must consider oceanic dissolved inputs as an additional source of 7Be and, possibly, of contaminants to

  2. Improvements in 230Th dating, 230Th and 234U half-life values, and U-Th isotopic measurements by multi-collector inductively coupled plasma mass spectrometry

    Cheng, Hai; Lawrence Edwards, R.; Shen, Chuan-Chou; Polyak, Victor J.; Asmerom, Yemane; Woodhead, Jon; Hellstrom, John; Wang, Yongjin; Kong, Xinggong; Spötl, Christoph; Wang, Xianfeng; Calvin Alexander, E.

    2013-06-01

    We have developed techniques for measuring 234U and 230Th on Faraday cups with precisions of 1-3 epsilon units (1 ɛ-unit=1 part in 104) using multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). Using a Thermo-Scientific Neptune with desolvation nebulization, we obtained ionization/transmission efficiencies of 1-2% for both U and Th. We set up protocols to correct for tailing, prepared U and Th gravimetric standards, tested a Th mass fractionation correction procedure based on U isotopes, and identified natural calcite samples likely to be in U-Th isotopic secular equilibrium. The measured atomic ratios, 234U/238U=54.970 (±0.019)×10-6 and 230Th/238U=16.916 (±0.018)×10-6, for these calcite samples were identical within errors (quoted 2σ uncertainties calculated combining all sources of error). Half-life values calculated from these ratios are consistent with previous values, but have much smaller errors: 245,620±260 a for 234U and 75,584±110 a for 230Th (quoted 2σ uncertainties calculated using all sources of error). In calculating a 230Th age, some of the systematic errors included in estimating the full error in the half-lives effectively cancel. Removing these uncertainties (uncertainty in the 238U half-life value, uncertainty in our gravimetric uranium and thorium standards, and uncertainty in the absolute isotopic composition of the uranium standard), yields effective uncertainties for the purposes of 230Th dating of ±70 a for the 234U half-life value and ±30 a for the 230Th half-life value. Under ideal circumstances, with our methods, the 2σ uncertainty in age, including uncertainty in half-life values is ±10 a at 10 ka, ±100 a at 130 ka, ±300 a at 200 ka, ±1 ka at 300 ka, ±2 ka at 400 ka, ±6 ka at 500 ka, and ±12 ka at 600 ka. The isotopic composition of a sample with an age <800 ka can clearly be resolved from the isotopic composition of a sample in secular equilibrium, assuming closed system behavior. Using these

  3. Cloning and Induced Expression Analysis of GhSAMDC2/3/4 in Cotton(Gossypium hirsutum L.)%棉花S-腺苷蛋氨酸脱羧酶基因(GhSAMDC2/3/4)的克隆及其诱导表达分析

    王凡龙; 朱华国; 程文翰; 刘永昌; 成新琪; 孙杰

    2015-01-01

    利用电子克隆结合RT-PCR技术克隆获得陆地棉(Gossvpium hirsutum L.)S-腺苷蛋氨酸脱羧酶(S-adenosylmethionine decarboxylase,SAMDC)基因家族3个基因,分别命名为GhSAMDC2、GhSAMDC3和GhSAMDC4.序列分析显示,该基因cDNA包含的upstream ORF(uORF)和main ORF(mORF)为植物SA MDC基因特征ORF,其中mORF长度分别为1068 bp、1110 bp和1032 bp,分别编码355、369和343个氨基酸.聚类分析表明,GhSAMDC2/3蛋白与可可树(Theobroma cacao) SAMDC聚为一类,且GhSAMDC2与Gh-SAMDC3蛋白亲缘关系最近;GhSAMDC4与拟南芥AtSAMDC4聚为一类.实时荧光定量PCR分析表明,GhSAMDC2在茎中表达相对较高,随着纤维发育其表达量不断增加,在纤维发育后期其表达量达到最高;GhSAMDC2/3/4在不同的胁迫条件下表现出不同的表达模式,GhSAMDC2受低温和干旱胁迫诱导最强烈,GhSAMDC3响应盐胁迫显著,GhSAMDC4受ABA诱导强烈.上述结果为进一步研究棉花SAMDC基因功能奠定了一定基础.

  4. Development of an analytical method for the determination of U-238, U-234, Th-232, Th-230, Th-228, Ra-228, Ra-226, Pb-210 and Po-210 and its application on environmental samples

    A comparison between the environmental impact by nuclear facilities with the burden suffered from natural radioactivity calls for studying the long-lived radionuclides of the U-238 and Th-232 decay series U-238, U-234, Th-232, Th-230, Th-228, Ra-228, Ra-226, Pb-210 and Po-210. This work describes the development of a fast isotope dilution analysis method allowing to separate with one sample solution U, Th, Ra, Pb and Po both from each other and, at the same time, from the matrix. To test its applicability, the method was used with samples consisting of soil, sediments, plants, water, carbon and air dust filter. The detection limit for the chemical yield attained of approx. 70% was 0.27 mBq per sample for Th-232, Th-230, Th-228, U-238, U-234 and Po-210. The detection limit for Pb-210 was 10 mBq per sample. On account of the influence by Ra-226 in the Ra-228 measurement and vice versa the detection limit is a function of the Ra-226 and Ra-228 concentrations, respectively, in the sample. The detection limits for the pure nuclides are 0.9 mBq per sample and 10 mBq per sample, respectively, for Ra-226 and Ra-228. (orig./HP)

  5. Determination of 234U/238U ratio: Comparison of multi-collector ICPMS and ICP-QMS for water, hair and nails samples, and comparison with alpha-spectrometry for water samples

    The 234U/238U ratio in water, hair and nails samples was determined by multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) and inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) and by alpha-spectrometry for the water samples only. A correlation of 0.99 was found between the two ICPMS methods and of 0.98 with alpha-spectrometry. The range of activity ratios was between 0.9 and 2.6 according to the MC-ICPMS measurements. The reproducibility of both ICPMS techniques was better than 4% for water samples containing 1μg l-1 of uranium and a 234U/238U atom ratio of 54.9 x 10-6. Sample preparation for the ICPMS consisted of dilution of water samples containing >10 μg l-1 of uranium and measurement time was ∼1 min, while alpha-spectrometry involved pre-concentration and separation of the uranium and counting times of 1000 min. (authors)

  6. Determination of the concentration of {sup 238}U, {sup 234}U, {sup 232}Th, {sup 228}Th, {sup 228}Ra, {sup 226}Ra and {sup 210}Pb in the feces of workers from a mining company of niobium and their families; Determinacao da concentracao de {sup 238}U, {sup 234}U, {sup 232}Th, {sup 228}Th, {sup 228}Ra, {sup 226}Ra e {sup 210}Pb na excrecao fecal de trabalhadores de uma mineradora de niobio e de seus familiares

    Oliveira, Roges de; Lopes, Ricardo T. [Coordenacao dos Programas de Pos-Graduacao de Engenharia (LIN/COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Nuclear. Lab. de Intrumentacao Nuclear; Melo, Dunstana R.; Juliao, Ligia M.Q.C. [Instituto de Radioprotecao e Dosimetria (SEMINIRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Servico de Monitoracao Individual Interna

    2005-07-01

    The object of this study consists of an open mine from which Niobium ore (pyrochlore) is extracted and a metallurgy company, where Fe-Nb alloys are produced for export. For geological reasons, the main ore is associated to natural radionuclides U and Th, and its decay products. The concentration of {sup 234}U, {sup 238}U, {sup 232}Th, {sup 226}Ra and {sup 228}Ra, {sup 228}Th, including {sup 210}Pb in fecal excretion of 12:0 am, 29 workers and 13 family members were determined. The technique employed for the determination of the elements was the sequential method of radiochemical separation, followed by alpha spectrometry and counting {alpha} and {beta} in proportional detector. Statistically significant difference was observed in the concentration of {sup 234}U and {sup 238}U, in feces samples, among the group of mining workers and family members; as well as for {sup 232}Th in the feces of workers of crushing and metallurgy groups when compared with the Family Group. No statistically significant difference was detected at a concentration of {sup 226}Ra, {sup 228}Ra and {sup 210}Pb, in feces of any group of workers of the installation in relation to the family group.

  7. 安徽铜陵地区矿山234例职业伤害者生存质量调查及其影响因素分析%Effect of occupational injury on quality of life: 234 cases in the mining area of Tongling, Anhui

    石小河; 胡志平

    2007-01-01

    背景:生存质量作为一种较全面体现新的健康观和医学模式的评价体系引入职业伤害领域,是对传统的治疗与康复效果评价方法的补充.目的:分析安徽铜陵地区矿山职业伤害者生存质量现状及其影响因素.设计:病例对照问卷调查,Logistic单因素分析和多因素分析.单位:铜陵有色职工总医院、铜陵有色公司矿山安全科.对象:选择2000-01/2005-12安徽铜陵有色金属(集团)公司下属4个矿山234例职业伤害者为工伤组,伤害等级均经该企业安全生产部门鉴定认可;选取本单位(部门)同性别206名等情况相似职工为对照组,所有受试对象均对检测项目知情同意.方法:问卷调查在2006-12完成,调查方法采用问卷调查法,由调查对象本人填写,对小学及以下文化程度或病情严重者,由他人通过询问其本人情况和感受而代为填写.①对两组人群社会人口学特征进行调查.②采用信度、效度及敏感度均较好的世界卫生组织生存质量-100量表作为主要调查工具,调查内容包括:影响因素调查(性别、年龄、职业、学历、婚姻、吸烟、饮酒、工资、工种、伤害等级、受伤部位、类型、患其它疾病、家庭人均收入、人均住房面积、事故类型、性格类型、睡眠状况等);反映生存质量不同维度调查:分别是生理机能领域(躯体疼痛、精力、睡眠),心理状态领域(幸福感、信心等5个方面),独立性领域(日常生活能力、工作能力等4个方面),社会关系领域(人际关系、社会交往等3个方面),物质生活环境领域(安全性、住房环境等8个方面),信仰领域(个人信仰),共计24个方面,每个方面有4个条目,再加上总体健康方面的4个条目,总计100个条目.每个条目采用线性评分法,最高5分、最低1分,生存质量自评总分条目1个,按百分制打分.③对工伤组受试对象生存质量一般情况进行

  8. Ultrafast thin-disk multipass laser amplifier delivering 1.4 kW (4.7 mJ, 1030 nm) average power converted to 820 W at 515 nm and 234 W at 343 nm.

    Negel, Jan-Philipp; Loescher, André; Voss, Andreas; Bauer, Dominik; Sutter, Dirk; Killi, Alexander; Ahmed, Marwan Abdou; Graf, Thomas

    2015-08-10

    We report on an Yb:YAG thin-disk multipass laser amplifier delivering sub-8 ps pulses at a wavelength of 1030 nm with 1420 W of average output power and 4.7 mJ of pulse energy. The amplifier is seeded by a regenerative amplifier delivering 6.5 ps pulses with 300 kHz of repetition rate and an average power of 115 W. The optical efficiency of the multipass amplifier was measured to be 48% and the beam quality factor was better than M2 = 1.4. Furthermore we report on the external second harmonic generation from 1030 nm to 515 nm using an LBO crystal leading to an output power of 820 W with 2.7 mJ of energy per pulse. This corresponds to a conversion efficiency of 70%. Additionally, 234 W of average power were obtained at the third harmonic with a wavelength of 343 nm. PMID:26367957

  9. The fission cross sections of 230Th, 232Th, 233U, 234U, 236U, 238U, 237Np, 239Pu and 242Pu relative 235U at 14.74 MeV neutron energy

    The measurement of the fission cross section ratios of nine isotopes relative to 235U at an average neutron energy of 14.74 MeV is described with particular attention to the determination of corrections and to sources of error. The results are compared to ENDF/B-V and to other measurements of the past decade. The ratio of the neutron induced fission cross section for these isotopes to the fission cross section for 235U are: 230Th - 0.290 +- 1.9%; 232Th - 0.191 +- 1.9%; 233U - 1.132 +- 0.7%; 234U - 0.998 +- 1.0%; 236U - 0.791 +- 1.1%; 238U - 0.587 +- 1.1%; 237Np - 1.060 +- 1.4%; 239Pu - 1.152 +- 1.1%; 242Pu - 0.967 +- 1.0%. 40 refs., 11 tabs., 9 figs

  10. Fragment-mass, kinetic energy, and angular distributions for 234U(n ,f ) at incident neutron energies from En=0.2 MeV to 5.0 MeV

    Al-Adili, A.; Hambsch, F.-J.; Pomp, S.; Oberstedt, S.; Vidali, M.

    2016-03-01

    This work investigates the neutron-induced fission of 234U and the fission-fragment properties for neutron energies between En=0.2 and 5.0 MeV with a special highlight on the prominent vibrational resonance at En=0.77 MeV. Angular, energy, and mass distributions were determined based on the double-energy technique by means of a twin Frisch-grid ionization chamber. The experimental data are parametrized in terms of fission modes based on the multimodal random neck-rupture model. The main results are a verified strong angular anisotropy and fluctuations in the energy release as a function of incident-neutron energy.

  11. Determination of 234U and 238U in seawater samples by alpha spectrometry after concentration of U(VI) onto hydrotalcite and co-precipitation with LaF3

    This paper presents a simple and accurate method for determination of uranium isotopes (234U and 238U) in seawater samples using alpha spectrometry. Uranium is pre-concentrated from seawater samples via adsorption on hydrotalcite at pH 6.5. The absorbent is dissolved into 50 ml of 8M HNO3; then filtered through a Dowex-1 column. U(VI) in the elution solution is reduced to U(IV) using zinc metal in 4M solution of HCl and then co-precipitated with LaF3. The chemical separation efficiency is found to be 97.12 ± 2.68%, eliminating the need of using 232U tracer in other published methods. This method is validated via comparison with results obtained using inductively coupled plasma mass spectrometry (ICP-MS) and neutron activation analysis (NAA) for three seawater samples. (orig.)

  12. Determination of 234U/238U, 235U/238U and 236U/238U Isotope Ratios in Urine Using Sector Field Inductively Coupled Plasma Mass Spectrometry (SF-ICP-MS)

    Xiao, Ge; Jones, Robert L.; Saunders, David; Caldwell, Kathleen L.

    2016-01-01

    Quantification of the isotopic composition of uranium in urine at low levels of concentration is important for assessing both military and civilian populations’ exposures to uranium. However, until now there has been no convenient, precise method established for rapid determination of multiple uranium isotope ratios. Here we report a new method to measure 234U/238U, 235U/238U and 236U/238U. It uses solid phase chelation extraction (via TRU columns) of actinides from the urine matrix, followed by measurement using a magnetic sector field inductively coupled plasma mass spectrometer (SF-ICP-MS - Thermo Element XR) equipped with a high efficiency nebulizer (Apex PFA microflow) and coupled with a membrane desolvating introduction system (Aridus II™). This method provides rapid and reliable results, and has been used successfully to analyze Certified Reference Materials (CRM). PMID:24563523

  13. Tracing of natural radionuclides mobility in deep sedimentary environment using radioactive (234U/238U) disequilibria: application to the Mesozoic formations of the Eastern part of the Paris Basin

    This thesis forms part of the geological investigations undertaken by the French agency for nuclear waste management, ANDRA, around the Meuse/Haute-Marne Underground Research Laboratory (URL) located in the Eastern part of the Paris Basin in order to evaluate the feasibility of high-level radioactive waste repository in deep argilite formations. The aim of the study is to examine the radionuclide migration in the deep Callovo-Oxfordian target argilite layer and its surrounding low- permeability Bathonian and Oxfordian limestone formations in order to assess the long term confining capacities of the sedimentary series. This study is based on measurement of radioactive disequilibria within U-series by Multiple- Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS). The high precision and accuracy achieved allowed to demonstrate the 234U/238U radioactive equilibrium in the Callovo-Oxfordian argilites. This result shows the uranium immobility in the target formation and provides a strong evidence for the current chemical stability and closure of the system for uranium and most probably for the other actinides. This is a fundamental result with respect to the problematic of disposal of high level radioactive waste in deep geological formation since it provides a in situ indication of the confining capacities of the clayey target formation in the current settings. Conversely, (234U/238U) disequilibria are systematically observed within zones, located in the surrounding carbonate formations, that are characterized by pressure dissolution structures (stylolites or dissolution seams). These disequilibria provide evidence for a discrete uranium relocation during the last two million years in the vicinity of stylolitic structures. This is a surprising result since it is generally supposed that these deep, low permeability, compact formations behave as closed system at the time scale of the U-series. (author)

  14. Multi-Institution Prospective Trial of Reduced-Dose Craniospinal Irradiation (23.4 Gy) Followed by Conformal Posterior Fossa (36 Gy) and Primary Site Irradiation (55.8 Gy) and Dose-Intensive Chemotherapy for Average-Risk Medulloblastoma

    Purpose: Limiting the neurocognitive sequelae of radiotherapy (RT) has been an objective in the treatment of medulloblastoma. Conformal RT to less than the entire posterior fossa (PF) after craniospinal irradiation might reduce neurocognitive sequelae and requires evaluation. Methods and Materials: Between October 1996 and August 2003, 86 patients, 3-21 years of age, with newly diagnosed, average-risk medulloblastoma were treated in a prospective, institutional review board-approved, multi-institution trial of risk-adapted RT and dose-intensive chemotherapy. RT began within 28 days of definitive surgery and consisted of craniospinal irradiation (23.4 Gy), conformal PF RT (36.0 Gy), and primary site RT (55.8 Gy). The planning target volume for the primary site included the postoperative tumor bed surrounded by an anatomically confined margin of 2 cm that was then expanded with a geometric margin of 0.3-0.5 cm. Chemotherapy was initiated 6 weeks after RT and included four cycles of high-dose cyclophosphamide, cisplatin, and vincristine. Results: At a median follow-up of 61.2 months (range, 5.2-115.0 months), the estimated 5-year event-free survival and cumulative incidence of PF failure rate was 83.0% ± 5.3% and 4.9% ± 2.4% (± standard error), respectively. The targeting guidelines used in this study resulted in a mean reduction of 13% in the volume of the PF receiving doses >55 Gy compared with conventionally planned RT. The reductions in the dose to the temporal lobes, cochleae, and hypothalamus were statistically significant. Conclusion: This prospective trial has demonstrated that irradiation of less than the entire PF after 23.4 Gy craniospinal irradiation for average-risk medulloblastoma results in disease control comparable to that after treatment of the entire PF

  15. Tracing of natural radionuclides mobility in deep sedimentary environment using radioactive ({sup 234}U/{sup 238}U) disequilibria: application to the Mesozoic formations of the Eastern part of the Paris Basin; Tracage de la mobilite des radionucleides naturels en milieu sedimentaire profond a l'aide des desequilibres radioactifs ({sup 234}U/{sup 238}U): application aux formations mesozoiques de l'est du Bassin de Paris

    Deschamps, P

    2003-11-01

    This thesis forms part of the geological investigations undertaken by the French agency for nuclear waste management, ANDRA, around the Meuse/Haute-Marne Underground Research Laboratory (URL) located in the Eastern part of the Paris Basin in order to evaluate the feasibility of high-level radioactive waste repository in deep argilite formations. The aim of the study is to examine the radionuclide migration in the deep Callovo-Oxfordian target argilite layer and its surrounding low- permeability Bathonian and Oxfordian limestone formations in order to assess the long term confining capacities of the sedimentary series. This study is based on measurement of radioactive disequilibria within U-series by Multiple- Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS). The high precision and accuracy achieved allowed to demonstrate the {sup 234}U/{sup 238}U radioactive equilibrium in the Callovo-Oxfordian argilites. This result shows the uranium immobility in the target formation and provides a strong evidence for the current chemical stability and closure of the system for uranium and most probably for the other actinides. This is a fundamental result with respect to the problematic of disposal of high level radioactive waste in deep geological formation since it provides a in situ indication of the confining capacities of the clayey target formation in the current settings. Conversely, ({sup 234}U/{sup 238}U) disequilibria are systematically observed within zones, located in the surrounding carbonate formations, that are characterized by pressure dissolution structures (stylolites or dissolution seams). These disequilibria provide evidence for a discrete uranium relocation during the last two million years in the vicinity of stylolitic structures. This is a surprising result since it is generally supposed that these deep, low permeability, compact formations behave as closed system at the time scale of the U-series. (author)

  16. The importance of tides for sediment dynamics in the deep sea—Evidence from the particulate-matter tracer 234Th in deep-sea environments with different tidal forcing

    Peine, Florian; Turnewitsch, Robert; Mohn, Christian; Reichelt, Theresa; Springer, Barbara; Kaufmann, Manfred

    2009-07-01

    Key aspects of deep-ocean fluid dynamics such as basin-scale (residual) and tidal flow are believed to have changed over glacial/interglacial cycles, with potential relevance for climatic change. To constrain the mechanistic links, magnitudes and temporal succession of events analyses of sedimentary paleo-records are of great importance. Efforts have been underway for some time to reconstruct residual-flow patterns from sedimentary records. Attempts to reconstruct tidal flow characteristics from deep-sea sediment deposits, however, are at a very early stage and first require a better understanding of the reflection of modern tides in sediment dynamics. In this context internal (baroclinic) tides, which are formed by the surface (barotropic) tide interacting with seafloor obstacles, are believed to play a particularly important role. Here we compare two modern deep-sea environments with respect to the effect of tides on sediment dynamics. Both environments are influenced by kilometre-scale topographic features but with vastly different tidal forcing: (1) two sites in the Northeast Atlantic (NEA) being surrounded by, or located downstream of, fields of short seamounts (maximum barotropic tidal current velocities ˜5 cm s -1); and (2) a site next to the Anaximenes seamount in the Eastern Mediterranean (EMed) (maximum barotropic tidal current velocities ˜0.5 cm s -1). With respect to other key fluid-dynamical parameters both environments are very similar. Signals of sedimentary particle dynamics, as influenced by processes taking place in the bottom boundary layer, were traced by the vertical water-column distribution of radioactive disequilibria (daughter/parent activity ratios≠1) between the naturally occurring, short-lived (half-life: 24.1 d) particulate-matter tracer 234Th relative to its very long-lived and non-particle-reactive parent nuclide 238U. Activity ratios of 234Th/ 238U1). The results of this study, therefore, add to the evidence suggesting that tides

  17. Potential Human Health Risk by Metal(loids, 234,238U and 210Po due to Consumption of Fish from the “Luis L. Leon” Reservoir (Northern México

    Mayra Y. Luna-Porres

    2014-06-01

    Full Text Available Concentrations of As, Cu, Fe, Hg, Pb and Zn and activity concentrations from 234,238U and 210Po in water, fillet, liver and gills were determined in three stocked fish species from the Luis L. Leon reservoir, located in Northern Mexico. The considered species were Lepomis cyanellus, Cyprinus carpio and Ictalurus furcatus. 238U and 234U activity concentration (AC in fillet samples showed values of 0.007–0.014 and 0.01–0.02 Bq∙kg−1 wet weight (ww, respectively. Liver samples for L. cyanellus, C. carpio and I. furcatus present 210Po AC of 1.16–3.26, 0.70–1.13 and 0.93–1.37 Bq∙kg−1 ww. Arsenic, mercury and lead concentration intervals in fillet samples were 0.13–0.39, 0.005–0.126 and 0.009–0.08 mg∙kg−1 ww, respectively, while in gill samples they were 0.11–0.43, 0.002–0.039 and 0.02–0.26 mg∙kg−1 ww. The elemental Bioaccumulation Factor (BAF for fish tissues with respect to their concentrations in water was determined. L. cyanellus showed the highest BAF values for As and total U, being BAFAs = 37 and 40 L∙kg−1 in fillet and gills, respectively, and BAFU total = 1.5 L∙kg−1 in fillet. I. furcatus showed the highest BAF values for Hg and Pb, being BAFHg = 40 and 13 L∙kg−1 in fillet and gills, and BAFPb = 6.5 and 22 L∙kg−1 in fillet and gills, respectively. Some metal(loid concentrations are slightly higher than European regulations for fish fillets. The difference in concentrations of metal(loids in fillet among the studied species is probably due to their differences in diet and habitat.

  18. Potential Human Health Risk by Metal(loid)s, 234,238U and 210Po due to Consumption of Fish from the “Luis L. Leon” Reservoir (Northern México)

    Luna-Porres, Mayra Y.; Rodríguez-Villa, Marco A.; Herrera-Peraza, Eduardo F.; Renteria-Villalobos, Marusia; Montero-Cabrera, María E.

    2014-01-01

    Concentrations of As, Cu, Fe, Hg, Pb and Zn and activity concentrations from 234,238U and 210Po in water, fillet, liver and gills were determined in three stocked fish species from the Luis L. Leon reservoir, located in Northern Mexico. The considered species were Lepomis cyanellus, Cyprinus carpio and Ictalurus furcatus. 238U and 234U activity concentration (AC) in fillet samples showed values of 0.007–0.014 and 0.01–0.02 Bq∙kg−1 wet weight (ww), respectively. Liver samples for L. cyanellus, C. carpio and I. furcatus present 210Po AC of 1.16–3.26, 0.70–1.13 and 0.93–1.37 Bq∙kg−1 ww. Arsenic, mercury and lead concentration intervals in fillet samples were 0.13–0.39, 0.005–0.126 and 0.009–0.08 mg∙kg−1 ww, respectively, while in gill samples they were 0.11–0.43, 0.002–0.039 and 0.02–0.26 mg∙kg−1 ww. The elemental Bioaccumulation Factor (BAF) for fish tissues with respect to their concentrations in water was determined. L. cyanellus showed the highest BAF values for As and total U, being BAFAs = 37 and 40 L∙kg−1 in fillet and gills, respectively, and BAFU total = 1.5 L∙kg−1 in fillet. I. furcatus showed the highest BAF values for Hg and Pb, being BAFHg = 40 and 13 L∙kg−1 in fillet and gills, and BAFPb = 6.5 and 22 L∙kg−1 in fillet and gills, respectively. Some metal(loid) concentrations are slightly higher than European regulations for fish fillets. The difference in concentrations of metal(loid)s in fillet among the studied species is probably due to their differences in diet and habitat. PMID:24968208

  19. The hyperfine structure of the 1s2ns2S and 1s2np2P states (n =2,3,4, and 5) for the lithium isoelectronic sequence

    The non-relativistic hyperfine structure parameters, the Fermi contact, the spin-dipolar, the orbital and the electronic quadrupole terms, of the lithium-like ground state and low-lying states, 1s2ns2S and 1s2np2P (n=2,3,4, and 5), are calculated with the full core plus correlation (FCPC) wave functions. With the 794- and 1185-term Slater-type expansions, the Fermi contact interactions of the 22S and 22P states in 7LiI are determined to be 2.90313 a.u. and -0.21359 a.u., respectively. By using the global identities, the Fermi contact term is also given for the ground state in LiI. The typical patterns of convergence of the expectation values of the Fermi contact interaction for the lithium 1s22s and 1s22p states are analyzed. The contribution from the core polarization is examined. The calculated results of the lithium-like systems from LiI to NeVIII are compared with the previous theoretical results obtained with other methods, and with the experimental data available in the literature. (orig.)

  20. Stoichiometric and catalytic activation of the alpha- and beta-2,3,4-tri-O-acetyl-5-thioxylopyranosyl bromide inside the cavity of the Pd3(dppm)3(CO)2+ cluster.

    Brevet, David; Mugnier, Yves; Lemaître, Frédéric; Lucas, Dominique; Samreth, Soth; Harvey, Pierre D

    2003-08-11

    The title cluster (Pd(3)(2+)) exhibits a pronounced affinity for Br(-) ions to form the very stable Pd(3)(Br)(+) adduct. Upon a 2-electron reduction, a dissociative process occurs generating Pd(3)(0) and eliminating Br(-) according to an ECE mechanism (electrochemical, chemical, electrochemical). At a lower temperature (i.e. -20 degrees C), both ECE and EEC processes operate. This cluster also activates the C-Br bond, and this work deals with the reactivity of Pd(3)(2+) with 2,3,4-tri-O-acetyl-5-thioxylopyranosyl bromide (Xyl-Br), both alpha- and beta-isomers. The observed inorganic product is Pd(3)(Br)(+) again, and it is formed according to an associative mechanism involving Pd(3)(2+).Xyl-Br host-guest assemblies. In an attempt to render the C-Br bond activation catalytic, these species are investigated under reduction conditions at two potentials (-0.9 and -1.25 V vs SCE). In the former case, the major product is Xyl-H, issued from a radical intermediate Xyl(*) abstracting an H atom from the solvent. Evidence for Xyl(*) is provided by the trapping with TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy) and DMPO (5,5'-dimethylpyrroline-N-oxyde). In the second case, only one product is observed, 3,4-di-O-acetyl-5-thioxylal, which is issued from the Xyl(-)() intermediate anion. PMID:12895115

  1. 32 CFR 234.1 - Definitions.

    2010-07-01

    .... Possession. Exercising direct physical control or dominion, with or without ownership, over property. State..., by compressed gas, or by spring power; any bow and arrow, crossbow, blowgun, spear gun,...

  2. 49 CFR 234.5 - Definitions.

    2010-10-01

    ... or more pairs of flashing lights are provided, there is not at least one flashing light pair... yellow green or fluorescent versions of these colors or other generally accepted high visibility colors... portion of a gate arm is missing if that portion normally had a gate arm flashing light attached....

  3. 32 CFR 234.7 - Disorderly conduct.

    2010-07-01

    ..., with intent to cause public alarm, nuisance, jeopardy, or violence, or knowingly or recklessly creating... injury or incite an immediate breach of the peace. (c) Makes noise that is unreasonable, considering...

  4. 24 CFR 234.26 - Project requirements.

    2010-04-01

    ... meet this occupancy requirement. (f) Limitations on conversion of rental housing to condominium use... entity (the same individual, investor group, partnership, or corporation) may own more than 10 percent...

  5. Energy Magazine. V. 23(4)

    The present issue contains a summary on energetic interconnections and regional integration schemes in Latin America and the Caribbean. A section is dedicated to Guyana and the impulse that it carries out in its energy sector considered as one of the fundamental pillars of its economic development. It also includes an article on the programs of energetic efficiency that OLADE executes. Besides it includes an article on the regulation of the environmental area linked to reform process of the energetic sector

  6. 49 CFR 234.231 - Fouling wires.

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS Maintenance...-rail grade crossing train detection circuit shall consist of at least two discrete conductors....

  7. 49 CFR 234.107 - False activation.

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS Response to Reports... false activation, a railroad having maintenance responsibility for the highway-rail grade...

  8. 14 CFR 234.2 - Definitions.

    2010-01-01

    ... schedule and availability of which are listed in a computer reservation system (CRS) regulated by 14 CFR... part 241 of this title. Qualifying airports will be specified periodically in accounting and reporting... title. Reporting carriers will be identified periodically in accounting and reporting directives...

  9. ISO/TC 234, Fisheries and Aquaculture

    Ramona I. Costea

    2009-01-01

    The largest standard developing organization, ISO, works these days at International Standards for Fisheries and Aquaculture. They created a technical committee divided in six work groups that will have to establish cage technology, aquaculture environmental management, aquaculture technology, food safety for aquaculture farms, traceability of fishery products and environmental monitoring on the seabed’s impact from marine finfish farms. These standards will promote the sustainable developmen...

  10. ISO/TC 234, Fisheries and Aquaculture

    Ramona I. Costea

    2009-01-01

    Full Text Available The largest standard developing organization, ISO, works these days at International Standards for Fisheries and Aquaculture. They created a technical committee divided in six work groups that will have to establish cage technology, aquaculture environmental management, aquaculture technology, food safety for aquaculture farms, traceability of fishery products and environmental monitoring on the seabed’s impact from marine finfish farms. These standards will promote the sustainable development of the fisheries and aquaculture sectors, will develop specifications for technical equipment adapted to the local environment, will improve surveillance and management of marine resources, will enable international agreement on sampling methods, will improve the safety of employees and will establish a common terminology.

  11. 32 CFR 234.10 - Weapons.

    2010-07-01

    ... are prohibited: (1) Possessing a weapon. (2) Carrying a weapon. (3) Using a weapon. (b) This section... use a weapon in support of a security, law enforcement, or other lawful purpose while on the...

  12. Reflection asymmetry in odd-A and odd-odd actinium nuclei

    Theoretical calculations and measurements indicate that octupole correlations are at a maximum in the ground states of the odd-proton nuclei Ac and Pa. It has been expected that odd-odd nuclei should have even larger amount of octupole-octupole correlations. We have recently made measurements on the structure of 224Ac. Although spin and parity assignments could not be made, two bands starting at 354.1 and 360.0 keV have properties characteristic of reflection asymmetric shape. These two bands have very similar rotational constants and also similar alpha decay rates, which suggest similarity between the wavefunctions of these bands. These signatures provide evidence for octupole correlations in these nuclides

  13. Bestimmung der Ionisationsenergie von Actinium und Ultraspurenanalyse von Plutonium mit resonanter Ionisationsmassenspektrometrie (RIMS)

    Waldek, Achim Marcus

    2001-01-01

    ZusammenfassungDie Resonanzionisationsmassenspektrometrie (RIMS) verbindet hohe Elementselektivität mit guter Nachweiseffizienz. Aufgrund dieser Eigenschaften ist die Methode für Ultraspurenanalyse und Untersuchungen an seltenen oder schwer handhabbaren Elementen gut geeignet. Für RIMS werden neutrale Atome mit monochromatischem Laserlicht ein- oder mehrfach resonant auf energetisch hoch liegende Niveaus angeregt und anschließend durch einen weiteren Laserstrahl oder durch ein elektrisches Fe...

  14. Radium-228 analysis of natural waters by Cherenkov counting of Actinium-228

    The activities of 228Ra in natural waters were determined by the Cherenkov counting of the daughter nuclide 228Ac. The radium was pre-concentrated on MnO2 and the radium purified via ion exchange and, after a 2-day period of incubation to allow for secular equilibrium between the parent-daughter 228Ra(228Ac), the daughter nuclide 228Ac was isolated by ion exchange according to the method of Nour et al. [2004. Radium-228 determination of natural waters via concentration on manganese dioxide and separation using Diphonix ion exchange resin. Appl. Radiat. Isot. 61, 1173-1178]. The Cherenkov photons produced by 228Ac were counted directly without the addition of any scintillation reagents. The optimum Cherenkov counting window, sample volume, and vial type were determined experimentally to achieve optimum Cherenkov photon detection efficiency and lowest background count rates. An optimum detection efficiency of 10.9±0.1% was measured for 228Ac by Cherenkov counting with a very low Cherenkov photon background of 0.317±0.013 cpm. The addition of sodium salicylate into the sample counting vial at a concentration of 0.1 g/mL yielded a more than 3-fold increase in the Cherenkov detection efficiency of 228Ac to 38%. Tests of the Cherenkov counting technique were conducted with several water standards of known activity and the results obtained compared closely with a conventional liquid scintillation counting technique. The advantages and disadvantages of Cherenkov counting compared to liquid scintillation counting methods are discussed. Advantages include much lower Cherenkov background count rates and consequently lower minimal detectable activities for 228Ra and no need for expensive environmentally unfriendly liquid scintillation cocktails. The disadvantages of the Cherenkov counting method include the need to measure 228Ac Cherenkov photon detection efficiency and optimum Cherenkov counting volume, which are not at all required when liquid scintillation analysis is used

  15. Linear free energy relationship applied to trivalent cations with lanthanum and actinium oxide and hydroxide structure

    Linear free energy relationships for trivalent cations with crystalline M2O3 and, M(OH)3 phases of lanthanides and actinides were developed from known thermodynamic properties of the aqueous trivalent cations, modifying the Sverjensky and Molling equation. The linear free energy relationship for trivalent cations is as ΔGf,MvX0=aMvXΔGn,M3+0+bMvX+βMvXrM3+, where the coefficients aMvX, bMvX, and βMvX characterize a particular structural family of MvX, rM3+ is the ionic radius of M3+ cation, ΔGf,MvX0 is the standard Gibbs free energy of formation of MvX and ΔGn,M3+0 is the standard non-solvation free energy of the cation. The coefficients for the oxide family are: aMvX=0.2705, bMvX=-1984.75 (kJ/mol), and βMvX=197.24 (kJ/molnm). The coefficients for the hydroxide family are: aMvX=0.1587, bMvX=-1474.09 (kJ/mol), and βMvX=791.70 (kJ/molnm).

  16. Actinium: A RESTful Runtime Container for Scriptable Internet of Things Applications

    Kovatsch, Matthias; Lanter, Martin; Duquennoy, Simon

    2012-01-01

    Programming Internet of Things (IoT) applications is challenging because developers have to be knowledgeable in various technical domains, from low-power networking, over embedded operating systems, to distributed algorithms. Hence, it will be challenging to find enough experts to provide software for the vast number of expected devices, which must also be scalable and particularly safe due to the connection to the physical world. To remedy this situation, we propose an architecture that pr...

  17. New method for large scale production of medically applicable Actinium-225 and Radium-223

    Alpha-emitters (211At, 212Bi, 213Bi, 223Ra, 225Ac) are promising for targeted radiotherapy of cancer. Only two alpha decays near a cell membrane result in 50% death of cancer cell and only a single decay inside the cell is required for this. 225Ac may be used either directly or as a mother radionuclide in 213Bi isotope generator. Production of 225Ac is provided by three main suppliers - Institute for Transuranium Elements in Germany, Oak Ridge National Laboratory in USA and Institute of Physics and Power Engineering in Obninsk, Russia. The current worldwide production of 225Ac is approximately 1.7 Ci per year that corresponds to only 100-200 patients that could be treated annually. The common approach for 225Ac production is separation from mother 229Th or irradiation of 226Ra with protons in a cyclotron. Both the methods have some practical limitations to be applied routinely. 225Ac can be also produced by irradiation of natural thorium with medium energy protons . Cumulative cross sections of 225Ac, 227Ac, 227Th, 228Th formations have been obtained recently. Thorium targets (1-9 g) were irradiated by 114-91 MeV proton beam (1-50 μA) at INR linear accelerator. After dissolution in 8 M HNO3 + 0.004 M HF thorium was removed by double LLX by HDEHP in toluene (1:1). Ac and REE were pre-concentrated and separated from Ra and most fission products by DGA-Resin (Triskem). After washing out by 0.01 M HNO3 Ac was separated from REE by TRU Resin (Triskem) in 3 M HNO3 media. About 6 mCi 225Ac were separated in hot cell with chemical yield 85%. The method may be upscaled for production of Ci amounts of the radionuclide. The main impurity is 227Ac (0.1% at the EOB) but it does not hinder 225Ac from being used for medical 225Ac/213Bi generators. (author)

  18. Synthesis of chelating agents for actinium 225 complexation and its application in radioimmunotherapy

    Immunotherapy with radiolabeled antibodies should allow fairly specific targeting of certain cancers. However, iodine 131 may not be the best isotope for tumor therapy because of its limited specific activity, low beta-energy, relatively long half life and strong gamma emission. Another approach to improve therapeutic efficacy is the use of replacement isotopes with better physical properties. Chelator that can hold radio-metals with high stability under physiological conditions are essential to avoid excessive damage to non-target cells; Moreover, the development of new bifunctional chelating agents is essential for this purpose. Accordingly, our efforts have been directed, for several years, to the synthesis of original chelating agents likely to form stable complexes in vivo with the numerous potential candidates for such applications. Therefore, we have developed a new simple and efficient synthesis pathway of 2-(4-iso-thio-cyanate-benzyl)-1,4,7,10,13,16- hexa-aza-cyclo-hexadecane- 1,4,7,10,13,16-hexa-acetic acid, though functionalized on the cycle by a termination allowed coupling to an antibody or any other biological substance such as a hapten. (author)

  19. Purification of selenium from thorium, uranium, radium, actinium and potassium impurities for low background measurements

    A technique of selenium purification from 232Th, 238U, 226,228Ra, 227Ac and 40K was developed. This technique is simple to perform and employs a minimum number of highly pure reagents (bidistilled water, nitric acid). Operations carried out during purification (elution, evaporation) practically exclude losses of the target product (chemical yields of Se > 99%). A test purification of 100 g of selenium was carried out using this technique. The efficiency of this technique was confirmed by low background gamma spectrometry of the purified selenium sample. Distribution coefficients of Th, U, Ra and Ac on DOWEX 50W- x 8 cation-exchange resin at different concentrations of selenium and nitric acid were experimentally determinated. Instrumental neutron activation analysis of bidistilled water, deionized water and nitric acid was performed. (orig.)

  20. Purification of selenium from thorium, uranium, radium, actinium and potassium impurities for low background measurements

    Rakhimov, A.V. [Joint Institute for Nuclear Research (JINR), Dubna (Russian Federation); Uzbek Academy of Sciences, Tashkent (Uzbekistan). Inst. of Nuclear Physics (INP AS RUz); Warot, G. [CEA-CNRS, Modane (France). Laboratoire Souterrain de Modane (LSM); Karaivanov, D.V. [Joint Institute for Nuclear Research (JINR), Dubna (Russian Federation); Institute for Nuclear Research and Nuclear Energy (INRNE), Sofia (Bulgaria); Kochetov, O.I.; Lebedev, N.A.; Filosofov, D.V. [Joint Institute for Nuclear Research (JINR), Dubna (Russian Federation); Mukhamedshina, N.M.; Sadikov, I.I. [Uzbek Academy of Sciences, Tashkent (Uzbekistan). Inst. of Nuclear Physics (INP AS RUz)

    2013-07-01

    A technique of selenium purification from {sup 232}Th, {sup 238}U, {sup 226,228}Ra, {sup 227}Ac and {sup 40}K was developed. This technique is simple to perform and employs a minimum number of highly pure reagents (bidistilled water, nitric acid). Operations carried out during purification (elution, evaporation) practically exclude losses of the target product (chemical yields of Se > 99%). A test purification of 100 g of selenium was carried out using this technique. The efficiency of this technique was confirmed by low background gamma spectrometry of the purified selenium sample. Distribution coefficients of Th, U, Ra and Ac on DOWEX 50W- x 8 cation-exchange resin at different concentrations of selenium and nitric acid were experimentally determinated. Instrumental neutron activation analysis of bidistilled water, deionized water and nitric acid was performed. (orig.)

  1. Overexpression of the catalytically impaired Taspase1 T234V or Taspase1 D233A variants does not have a dominant negative effect in T(4;11 leukemia cells.

    Carolin Bier

    Full Text Available BACKGROUND: The chromosomal translocation t(4;11(q21;q23 is associated with high-risk acute lymphoblastic leukemia of infants. The resulting AF4•MLL oncoprotein becomes activated by Taspase1 hydrolysis and is considered to promote oncogenic transcriptional activation. Hence, Taspase1's proteolytic activity is a critical step in AF4•MLL pathophysiology. The Taspase1 proenzyme is autoproteolytically processed in its subunits and is assumed to assemble into an αββα-heterodimer, the active protease. Therefore, we investigated here whether overexpression of catalytically inactive Taspase1 variants are able to interfere with the proteolytic activity of the wild type enzyme in AF4•MLL model systems. METHODOLOGY/FINDINGS: The consequences of overexpressing the catalytically dead Taspase1 mutant, Taspase1(T234V, or the highly attenuated variant, Taspase1(D233A, on Taspase1's processing of AF4•MLL and of other Taspase1 targets was analyzed in living cancer cells employing an optimized cell-based assay. Notably, even a nine-fold overexpression of the respective Taspase1 mutants neither inhibited Taspase1's cis- nor trans-cleavage activity in vivo. Likewise, enforced expression of the α- or β-subunits showed no trans-dominant effect against the ectopically or endogenously expressed enzyme. Notably, co-expression of the individual α- and β-subunits did not result in their assembly into an enzymatically active protease complex. Probing Taspase1 multimerization in living cells by a translocation-based protein interaction assay as well as by biochemical methods indicated that the inactive Taspase1 failed to assemble into stable heterocomplexes with the wild type enzyme. CONCLUSIONS: Collectively, our results demonstrate that inefficient heterodimerization appears to be the mechanism by which inactive Taspase1 variants fail to inhibit wild type Taspase1's activity in trans. Our work favours strategies targeting Taspase1's catalytic activity

  2. The particulate {sup 7}Be/{sup 210}Pb{sub xs} and {sup 234}Th/{sup 210}Pb{sub xs} activity ratios as tracers for tidal-to-seasonal particle dynamics in the Gironde estuary (France): Implications for the budget of particle-associated contaminants

    Saari, Hanna-Kaisa [Universite de Bordeaux, UMR5805 EPOC, F-33405 Talence Cedex (France); Schmidt, Sabine, E-mail: s.schmidt@epoc.u-bordeaux1.fr [CNRS, UMR5805 EPOC, F-33405 Talence Cedex (France); Castaing, Patrice; Blanc, Gerard [Universite de Bordeaux, UMR5805 EPOC, F-33405 Talence Cedex (France); Sautour, Benoit [Universite de Bordeaux, UMR5805 EPOC, Station Marine d' Arcachon, F-33120 Arcachon (France); Masson, Olivier [IRSN, BP 3, 13115 Saint Paul Lez Durance (France); Cochran, J. Kirk [Marine Sciences Research Center, School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York 11794-5000 (United States)

    2010-09-15

    The short-lived natural radionuclides {sup 7}Be (T{sub 1/2} = 53 days), {sup 234}Th{sub xs} (T{sub 1/2} = 24.1 days) and {sup 210}Pb{sub xs} (T{sub 1/2} = 22.3 years), i.e. {sup 234}Th and {sup 210}Pb in excesses of that supported within particles by the decay of their parent isotopes, were analysed in suspended particulate matter (SPM) to study the particle dynamics in the Gironde fluvial estuarine system (France), strongly impacted by heavy metal pollution. From surveys of this land-ocean interface in 2006 and 2007, we established a times series of these radioisotopes and of their activity ratios ({sup 7}Be/{sup 210}Pb{sub xs} and {sup 234}Th/{sup 210}Pb{sub xs} ARs) in particles sampled under different hydrological conditions. The particulate {sup 7}Be/{sup 210}Pb{sub xs} AR varies along the fluvial estuarine system mainly due to variations in {sup 7}Be activities, controlled by riverine, oceanic and atmospheric inputs and by resuspension of old {sup 7}Be-deficient sediments. These processes vary with river discharge, tidal cycle and season. Therefore, seasonal particle transport processes can be described using variations of the SPM {sup 7}Be/{sup 210}Pb{sub xs} ARs. During high river discharge, the SPM {sup 7}Be/{sup 210}Pb{sub x} ARs decrease from river to the ocean. The turbidity maximum zone (TMZ) is dispersed and the particles, and the associated contaminants, are rapidly transported from river to coastal waters, without significant retention within the TMZ. During low river discharge, the TMZ intrudes into the fluvial estuary, and the lowest {sup 7}Be/{sup 210}Pb{sub x} ARs are observed there due to resuspension of {sup 7}Be-deficient sediments. Away from the TMZ, from the middle to lower estuary, SPM {sup 7}Be/{sup 210}Pb{sub x} ARs increase, indicating that the particles have been recently tagged with {sup 7}Be. We explain this trend as being caused by marine input of dissolved radionuclides, as traced by SPM {sup 234}Th/{sup 210}Pb{sub xs} ARs

  3. The identification of soil radionuclides in the area of Puspiptek and surrounding

    The area of PUSPIPTEK and the surrounding are potentially exposed by radionuclides, because the operation of the nuclear research plant. The PPTN Serpong was operated long than 10 years, therefore soil radioactivity need to evaluate. The determination of radioactivity in the soil samples which be taken from research location using gamma spectrometry on June-August. The result of the research identified natural radionuclides K-40; Thorium decay series Ac-228, Bi-212, Pb-212, Tl-208, Ra-224 and Rn-220; Uranium decay series Bi-214, Pa-234, Pb-214 and Actinium decay series Bi-211, Po-211. There are no identification radionuclides produce from the activation of PPTN Serpong

  4. The Technological Enhancement of Normally Occurring Radioactive Materials in Red Mud due to the Production of Alumina

    Maurice O. Miller

    2016-01-01

    Full Text Available This study investigates the level of technological enhancement of normally occurring radioactive materials (TENORM in the red mud waste due to the production of alumina in Jamaica. Technological enhancements factors (TEF were determined for the uranium, thorium, actinium series, their progenies, and the nonseries potassium-40 using gamma spectrometry. The study concluded that bauxite production technologically enhances the uranium progenies Th-234, Pb-214, Bi-214, and Pa-234 and the thorium-232 progenies Ac-228, Pb-212, and Bi-212 in red mud. The actinium series was technologically enhanced, but K-40 and the thorium daughter, Tl-208, were reduced. The spectrometric comparison of Tl-208 (at 510 keV was unexpected since its other photopeaks at 583 keV, 934 keV, and 968 keV were markedly different. An explanation for this anomaly is discussed. An explanation regarding the process of accumulation and fractionation of organically derived phosphate deposits and potassium-feldspar is offered to explain the spectrometric differences between the alumina product and its waste material, red mud.

  5. Purification of radium-226 for the manufacturing of actinium-225 in a cyclotron for alpha-immunotherapy; Radium-Aufreinigung zur Herstellung von Actinium-225 am Zyklotron fuer die Alpha-Immuntherapie

    Marx, Sebastian Markus

    2014-09-23

    The thesis describes the development of methods for the purification of Ra-226. The objective was to obtain the radionuclide in the quality that is needed to be used as starting material in the manufacturing process for Ac-225 via proton-irradiated Ra-226. The radionuclide has been gained efficiently out of huge excesses of impurities. The high purity of the obtained radium affords its use as staring material in a pharmaceutical manufacturing process.

  6. Renal uptake of bismuth-213 and its contribution to kidney radiation dose following administration of actinium-225-labeled antibody

    Schwartz, J; O' Donoghue, J A; Humm, J L [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Jaggi, J S [Bristol-Myers Squibb, Plainsboro, NJ (United States); Ruan, S; Larson, S M [Nuclear Medicine Service Department of Radiology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); McDevitt, M; Scheinberg, D A, E-mail: schwarj1@mskcc.org [Molecular Pharmacology and Chemistry, Sloan-Kettering Institute, 1275 York Avenue, New York, NY 10065 (United States)

    2011-02-07

    Clinical therapeutic studies using {sup 225}Ac-labeled antibodies have begun. Of major concern is renal toxicity that may result from the three alpha-emitting progeny generated following the decay of {sup 225}Ac. The purpose of this study was to determine the amount of {sup 225}Ac and non-equilibrium progeny in the mouse kidney after the injection of {sup 225}Ac-huM195 antibody and examine the dosimetric consequences. Groups of mice were sacrificed at 24, 96 and 144 h after injection with {sup 225}Ac-huM195 antibody and kidneys excised. One kidney was used for gamma ray spectroscopic measurements by a high-purity germanium (HPGe) detector. The second kidney was used to generate frozen tissue sections which were examined by digital autoradiography (DAR). Two measurements were performed on each kidney specimen: (1) immediately post-resection and (2) after sufficient time for any non-equilibrium excess {sup 213}Bi to decay completely. Comparison of these measurements enabled estimation of the amount of excess {sup 213}Bi reaching the kidney ({gamma}-ray spectroscopy) and its sub-regional distribution (DAR). The average absorbed dose to whole kidney, determined by spectroscopy, was 0.77 (SD 0.21) Gy kBq{sup -1}, of which 0.46 (SD 0.16) Gy kBq{sup -1} (i.e. 60%) was due to non-equilibrium excess {sup 213}Bi. The relative contributions to renal cortex and medulla were determined by DAR. The estimated dose to the cortex from non-equilibrium excess {sup 213}Bi (0.31 (SD 0.11) Gy kBq{sup -1}) represented {approx}46% of the total. For the medulla the dose contribution from excess {sup 213}Bi (0.81 (SD 0.28) Gy kBq{sup -1}) was {approx}80% of the total. Based on these estimates, for human patients we project a kidney-absorbed dose of 0.28 Gy MBq{sup -1} following administration of {sup 225}Ac-huM195 with non-equilibrium excess {sup 213}Bi responsible for approximately 60% of the total. Methods to reduce renal accumulation of radioactive progeny appear to be necessary for the success of {sup 225}Ac radioimmunotherapy.

  7. Purification of radium-226 for the manufacturing of actinium-225 in a cyclotron for alpha-immunotherapy

    The thesis describes the development of methods for the purification of Ra-226. The objective was to obtain the radionuclide in the quality that is needed to be used as starting material in the manufacturing process for Ac-225 via proton-irradiated Ra-226. The radionuclide has been gained efficiently out of huge excesses of impurities. The high purity of the obtained radium affords its use as staring material in a pharmaceutical manufacturing process.

  8. Distribution of trace elements in land plants and botanical taxonomy with special reference to rare earth elements and actinium

    Distribution profiles of trace elements in land plants were studied by neutron activation analysis and radioactivity measurements without activation. Number of botanical samples analyzed were more than three thousand in which more than three hundred botanical species were included. New accumulator plants of Co, Cr, Zn, Cd, rare earth elements, Ac, U, etc., were found. Capabilities of accumulating trace elements can be related to the botanical taxonomy. Discussions are given from view points of inorganic chemistry as well as from botanical physiology

  9. Association between ε2/3/4, Promoter Polymorphism (−491A/T, −427T/C, and −219T/G at the Apolipoprotein E Gene, and Mental Retardation in Children from an Iodine Deficiency Area, China

    Jun Li

    2014-01-01

    Full Text Available Background. Several common single-nucleotide polymorphisms (SNPs at apolipoprotein E (ApoE have been linked with late onset sporadic Alzheimer’s disease and declining normative cognitive ability in elder people, but we are unclear about their relationship with cognition in children. Results. We studied -491A/T, -427T/C, and -219G/T promoter polymorphisms and ε2/ε3/ε4 at ApoE among children with mental retardation (MR, n=130, borderline MR (n=124, and controls (n=334 from an iodine deficiency area in China. The allelic and genotypic distribution of individual locus did not significantly differ among three groups with Mantel-Haenszel χ2 test (P>0.05. However, frequencies of haplotype of -491A/-427T/-219T/ε4 were distributed as MR > borderline MR > controls (P uncorrected = 0.004, indicating that the presence of this haplotype may increase the risk of disease. Conclusions. In this large population-based study in children, we did not find any significant association between single locus of the four common ApoE polymorphisms (-491A/T, -427T/C, -219T/G, and ε2/3/4 and MR or borderline MR. However, we found that the presence of ATTε4 haplotype was associated with an increased risk of MR and borderline MR. Our present work may help enlarge our knowledge of the cognitive role of ApoE across the lifespan and the mechanisms of human cognition.

  10. Les isotopes radioactifs de la série de l’uranium-238 (222Rn, 226Ra, 234U et 238U) dans les eaux thermales de Suisse: sites d’Yverdon-les-Bains, Moiry, Loèche-les-Bains, Saxon, Val d’Illiez, Bad Ragaz, Delémont, Lavey-les-Bains, Brigerbad et Combioula

    Gainon, François; Zwahlen, François

    2008-01-01

    Les isotopes radioactifs de la série de désintégration de l’uranium-238 sont présents en quantité variable dans les eaux souterraines. Cette étude a pour but de mesurer quatre isotopes de cette chaîne de désintégration (222Rn, 226Ra, 238U et 234U) dans le contexte des systèmes d’écoulement profonds, d’en étudier leur mobilité et d’en déduire les informations qu’ils peuvent apporter à la compréhension des aquifères profonds. L’étude a été menée sur onze sites situés en Suisse, en partie dans l...

  11. Dicty_cDB: VFL234 [Dicty_cDB

    Full Text Available |pid:none) Homo sapiens acid sphingomyelinase (SM... 128 4e-28 protein update 200...gomyelinase. 128 4e-28 AE013599_4075( AE013599 |pid:none... AK292388_1( AK292388 |pid:none) Homo sapiens cDNA FLJ77600 complet... 129 3e-28 X59960_1( X59960 |pid:none) H.sapiens mRNA for sphin

  12. 16 CFR 23.4 - Misrepresentation as to gold content.

    2010-01-01

    ... items having surfaces and parts of surfaces that are subject to different degrees of wear, the thickness... descriptions of industry products and parts thereof are subject to the applicable tolerances of the...

  13. Dicty_cDB: SSL234 [Dicty_cDB

    Full Text Available PID:g7747, mRNA sequence. 46 0.001 2 AI534743 |AI534743.1 SD07749.5prime SD Drosophila melanogaster Schneider...uence. 46 0.002 2 AI532687 |AI532687.1 SD04275.5prime SD Drosophila melanogaster Schneider

  14. 48 CFR 52.234-4 - Earned Value Management System.

    2010-10-01

    ... an Integrated Baseline Review (IBR). If a pre-award IBR has not been conducted, a post award IBR... an IBR at— (1) Exercise of significant options; or (2) Incorporation of major modifications....

  15. 2-(3,4-Difluorophenyl-1H-benzimidazole

    M. S. Krishnamurthy

    2013-11-01

    Full Text Available In the title molecule, C13H8F2N2, the dihedral angle between the benzimidazole ring system and the difluoro-substituted benzene ring is 30.0 (1°. In the crystal, molecules are linked by N—H...N hydrogen bonds, forming chains along [010]. In addition, weak C—H...F hydrogen bonds connect chains into a two-dimensional network parallel to (001. A weak C—H...π interaction is observed between an H atom of the benzimidazole ring sytem and the π system of the difluoro-substituted benzene ring.

  16. 49 CFR 234.217 - Flashing light units.

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS Maintenance... interior of the unit. Roundels and reflectors shall be clean and in good condition. (c) All light...

  17. Teenage Suicide: What Can the Schools Do? Fastback 234.

    Pfeifer, Jerilyn K.

    This document is a short summary of teenage suicide issues intended for use by teachers. Possible causes for teenage suicide are discussed, including: (1) chemical abuse; (2) unrealistic view of death; (3) the nuclear threat; (4) societal changes; (5) family changes; (6) lifestyle decisions; (7) academic pressures; and (8) the success code.…

  18. Ramp compression of magnesium oxide to 234 GPa

    Single-crystal magnesium oxide (MgO) samples were ramp compressed to above 200 GPa pressure at the Omega laser facility. Multi-stepped MgO targets were prepared using lithography and wet etching techniques. Free surface velocities of ramp-compressed MgO were measured with a VISAR. The sound velocity and stress-density response were determined using an iterative Lagrangian analysis. The measured equation of state is consistent with expectations from previous shock and static data as well as with a recent X-ray diffraction measurement under ramp loading. The peak elastic stresses observed in our samples have amplitudes of 3–5.5 GPa, decreasing with propagation distance.

  19. 24 CFR 234.255 - Cross-reference.

    2010-04-01

    ....389Waived title objections. 203.420Nature of Mutual Mortgage Insurance Fund. 203.421Allocation of Mutual Mortgage Insurance Fund income or loss. 203.422Right and liability under Mutual Mortgage Insurance Fund...) to section 203 of the Act, one- to four-family, and the Mutual Mortgage Insurance Fund, shall...

  20. 49 CFR 234.275 - Processor-based systems.

    2010-10-01

    ... made subject to 49 CFR part 236, subpart H, by submitting a Product Safety Plan as prescribed in § 236... justifications. The Product Safety Plan in accordance with 49 CFR 236.907—or a PTC Development Plan and PTC Safety Plan required to be filed in accordance with 49 CFR 236.1013 and 236.1015—must explain how...

  1. 49 CFR 234.211 - Security of warning system apparatus.

    2010-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS.... Highway-rail grade crossing warning system apparatus shall be secured against unauthorized entry....

  2. 49 CFR 234.201 - Location of plans.

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS Maintenance... maintenance and testing shall be kept at each highway-rail grade crossing warning system location. Plans...

  3. 49 CFR 234.225 - Activation of warning system.

    2010-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS...-rail grade crossing warning system shall be maintained to activate in accordance with the design of the... operation of through trains before the grade crossing is occupied by rail traffic....

  4. 36 CFR 223.234 - Determination of responsibility.

    2010-07-01

    ... declared high bidder has a satisfactory record of integrity and business ethics; (4) The declared high... arose from circumstances beyond their reasonable control. (c) Affiliated concerns, as defined in 36...

  5. Dicty_cDB: VHE234 [Dicty_cDB

    Full Text Available *xvsvsifmmspstlmpstxvvvks sqllvvysmlln*lppqlx*nqft**kllpxktllvvftlysivvxvlllvknvvsvphy xls...llsrnycpxkrywwyllctqssxrycyw*rtxyrfpii xcqssftsirilrfhr*ftfphcrssfptmcfrslgfnwccqqx*esh*srfshqkxkrf sprnprs*qiprktlnxlsrxls

  6. 二苯乙烯苷对2型糖尿病大鼠氧化应激、炎症反应及主动脉细胞凋亡相关基因的影响%Effects of 2,3,4', 5-tetrahydroxystilbene-2-O-beta-D-glucoside on oxidative stress, inflammation and aorta cell apoptosis gene in type 2 diebetes rats

    张园; 董林; 许晓乐; 王玉琴; 张伟

    2012-01-01

    目的 研究二苯乙烯苷(TSG)对T2DM大鼠氧化应激、炎症反应及主动脉细胞凋亡相关基因的影响,并探讨其可能机制. 方法 采用高脂喂养联合低剂量STZ(40 mg/kg)的方法建立T2DM大鼠模型后,TSG(60、120mg/kg)、辛伐他汀(SV,2 mg/kg)灌胃治疗6周. 结果 与模型组比较,SV治疗组、TSG治疗组超氧化物歧化酶(SOD)活性、HDL-C水平升高(P<0.05),TG、TC、LDL-C、丙二醛(MDA)、FFA、TNF-α、单核细胞趋化蛋白-1(MCP-1)水平降低(P<0.05).免疫组化测大鼠主动脉核因子κB(NF-κB)、Fas表达下降(P<0.05),Bcl-2表达增强(P<0.05). 结论 TSG对T2DM大鼠有抗氧化、抗炎作用,并能抑制主动脉细胞凋亡相关基因的表达.%Objective To discuss the effects of 2,3,4', 5-tetrahydroxystilbene-2-Obeta-D-glucoside (TSG) on oxidative stress, inflammation and aorta cell apoptosis gene in type 2 diabetic rats in vivo, and explore its potential mechanisms. Methods Type 2 diabetes of SD rats was induced by high-fat diet and single intraperitoneal injection of STZ (40 mg/kg). The successful diabetic rat models were randomized into normal control group, diabetes group, simvastatin (2 mg/kg) in the positive control group, low-and high-dose treatment groups (TSG 60 mg/kg, 120 mg/kg). After 6 weeks' treatment of gavage, the level of oxidative stress, inflammation and aorta cell apoptosis were measured. Results Compared with the model group, in the SV and TSG groups, the levels of SOD and HDLC increased (P<0. 05) , while the levels of TG, TC, LDLC, MDA, FFA, TNF-α, and MCP-1 decreased (P<0. 05). Detected by immuno-histochemistry in aorta, the expressions of NF-kB and Fas protein were lower (P<0. 05) and expression of Bcl-2 protein was higher (P

  7. 2-[3-(4-Methoxyphenyl-1-phenyl-1H-pyrazol-5-yl]phenol

    2009-03-01

    Full Text Available The title compound, C22H18N2O2, was derived from 1-(2-hydroxyphenyl-3-(4-methoxyphenylpropane-1,3-dione. The central pyrazole ring forms dihedral angles of 16.83 (5, 48.97 (4 and 51.68 (4°, respectively, with the methoxyphenyl, phenyl and hydroxyphenyl rings. The crystal packing is stabilized by O—H...N hydrogen bonding.

  8. Dichlorido{2-[(3,4-dimethylphenyliminomethyl]pyridine-κ2N,N′}copper(II

    Mehdi Khalaj

    2011-11-01

    Full Text Available In the title complex, [CuCl2(C14H14N2], the CuII atom exhibits a very distorted tetrahedral coordination geometry involving two chloride ions and two N-atom donors from the Schiff base ligand. The range for the six bond angles about the Cu2+ cation is 81.49 (11–145.95 (9°. The chelate ring including the CuII atom is approximately planar, with a maximum deviation of 0.039 (4 Å for one of the C atoms; this plane forms a dihedral angle of 46.69 (9° with the CuCl2 plane.

  9. Preparing for High Technology: CAD/CAM Programs. Research & Development Series No. 234.

    Abram, Robert; And Others

    This guide is one of three developed to provide information and resources to assist in planning and developing postsecondary technican training programs in high technology areas. It is specifically intended for vocational-technical educators and planners in the initial stages of planning a specialized training option in computer-aided design (CAD)…

  10. Carbonation of concrete incorporating high volumes of fly ash[ACI SP-234-19

    Bouzoubaa, N.; Tamtsia, B.; Chevrier, R.L.; Bilodeau, A.; Malhotra, V.M. [Natural Resources Canada, Ottawa, ON (Canada). CANMET International Centre for Sustainable Development of Cement and Concrete; Zhang, M.H. [National Univ. of Singapore (Singapore). Dept. of Civil Engineering

    2006-07-01

    Carbonation of concrete involves the chemical interaction of atmospheric carbon dioxide (CO{sub 2}) and calcium hydroxide (Ca(OH){sub 2}) liberated during cement hydration. In high-volume fly ash (HVFA) concrete, the amount of calcium hydroxide and the binding of carbon dioxide will be greatly reduced due to its lower portland cement content and the pozzolanic-reaction. Therefore, the carbonation resistance of the HVFA concrete is reduced. This study investigated 3 HVFA concrete mixtures incorporating 58 per cent of fly ash, each made with a different fly ash. The mixtures also incorporated 2 control portland cement concrete mixtures, one with a water to cementitious materials ratio of 0.32 and the other with a 28-day compressive strength equivalent to that of the HVFA concrete. Before the accelerated carbonation test, the concrete was subjected to 3 different curing modes. The compressive strength of the hardened concrete was summarized along with the slump, unit weight and air content of the fresh concrete. The study showed that the effect of fly ash on the carbonation resistance of concrete is mainly due to the reactivity of fly ash and its effect on the microstructure of the hardened cement paste in the concrete. A concrete composed of low reactivity fly ash will develop a microstructure that becomes denser with a longer moist curing period. Therefore, the penetration of CO{sub 2} into the concrete will be slower. For both the HVFA and the control portland cement concrete, the carbonation depth of the concrete was found to decrease with an increase in the duration of moisture curing from 7 to 28 days. It was concluded that carbonation is not an issue for well-cured HVFA concrete because of the low water-cementitious materials ratio, the dense structure and low permeability of the concrete. 19 refs., 6 tabs., 11 figs.

  11. 77 FR 234 - Rules and Regulations Under the Textile Fiber Products Identification Act

    2012-01-04

    .... SUPPLEMENTARY INFORMATION: On November 7, 2011, the Commission published its ANPR (76 FR 68690) seeking comment...; ] FEDERAL TRADE COMMISSION 16 CFR Part 303 Rules and Regulations Under the Textile Fiber Products... section below. Write ``Textile Rules, 16 CFR Part 303, Project No. P948404'' on your comment, and...

  12. Assessing the durability of concrete regarding ASR[ACI SP-234-15

    Stark, J.; Giebson, C. [Bauhaus Univ., Weimar (Germany). F.A. Finger-Inst. for Building Materials Sciences

    2006-07-01

    Damages on concrete structures caused by alkali-aggregate reaction (AAR) were discussed. In Germany, the first damage caused by the alkali-silica reaction (ASR) occurred on a bridge that was built in 1964 and which had to be demolished in 1968 due to the loss of structural stability. As a result of intensive research into the cause of damage, the first Alkali-Guideline was published in 1974 by the German Committee for Reinforced Concrete. The guideline made it possible to classify alkali-reactive aggregates which contained opaline sandstone and flint. In order to prevent deleterious ASR, the guidelines proposed clear measures for moisture, external alkali supply and cement content. The guidelines were revised many times over the past decades to include other rock type aggregates that also posed problems. The guideline is going to be revised one more time to include testing methods that assess the influence of an external alkali supply, such as de-icing solutions, for pavement concretes. The cyclic climate storage was used and proved as an appropriate method. It was concluded that the new mortar bar test and cyclic climate storage represent more opportunities to assess the durability of concretes regarding ASR due to alkali-reactive slow/late aggregates. 17 refs., 2 tabs., 11 figs.

  13. 5-(4-Bromophenyl-2-(3,4-methylenedioxyphenyl-3-methylsulfanyl-1-benzofuran

    Hong Dae Choi

    2009-10-01

    Full Text Available The title compound, C22H15BrO3S, crystallizes with four molecules in the asymmetric unit. The 4-bromophenyl rings are rotated out of the benzofuran planes, with dihedral angles for the four molecules of 20.8 (2, 17.8 (2, 23.5 (4 and 23.9 (4°. The dihedral angles between the 3,4-methylenedioxyphenyl ring and the benzofuran plane are 13.5 (2, 7.1 (2, 18.6 (3 and 14.2 (3° in the four molecules. The crystal structure is stabilized by weak nonclassical intermolecular C—H...O hydrogen bonds. The crystal structure also exhibits intermolecular aromatic π–π interactions between the benzene and furan rings and between the 4-bromophenyl and 3,4-methylenedioxyphenyl rings from molecules of the same type; the centroid–centroid distances are 3.92 (1 and 3.79 (1, 3.91 (1, 3.77 (1 and 3.77 (1, and 3.79 (1 and 3.75 (1Å in the four molecules.

  14. Roger COLOMBANI, Des escrocs magnifiques. Les grands destins, Paris, Flammarion, 1994, 234 p.

    Bayard, Françoise

    2008-01-01

    Par un spécialiste du grand banditisme et du fait divers contemporain, la présentation, en quelques pages chacun de seize "escrocs" : le marquis de Rayes qui au XIXe siècle vend la Nouvelle-Irlande au prix fort, John Law, Ferdinand de Lesseps, Wilson (le gendre de Grévy), Thérèse Humbert qui vit 17 ans à crédit, Bolo Pacha, le banquier Oustric, Marthe Hanau, le comte Lustig qui vendit la Tour Eiffel, Stavisky, le ferrailleur Joanovici, Marius Jacob (le monte en l'air modèle d'Arsène Lupin), P...

  15. Molecular Properties and Evaluation of Indion 234–Ondansetron Resinates

    Shah, S; Pandya, S.; Bhalekar, MR

    2010-01-01

    Ondansetron is a serotonin 5HT3 antagonist; anti-emetic drug. Bitter taste of the ondansetron is a major problem in ensuring patient compliance. The study was designed to formulate tasteless complexes of ondansetron with ion exchange resin and evaluate molecular properties of drug complex. The drug-loading process was carried out using various resins and was optimized using different drug:resin ratio and pH. Resinates were characterized by infrared spectroscopy, thermal analysis, and X-ray po...

  16. 24 CFR 234.259 - Claim procedure-graduated payment mortgages.

    2010-04-01

    ... HOUSING AND URBAN DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES CONDOMINIUM OWNERSHIP MORTGAGE INSURANCE Contract Rights and Obligations-Individually Owned...

  17. 24 CFR 234.260 - Assignment of mortgage and certificate by mortgagee.

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Assignment of mortgage and... COMMISSIONER, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES CONDOMINIUM OWNERSHIP MORTGAGE INSURANCE Contract Rights and...

  18. Explaining the Decline in Teen Labor Force Participation. Chicago Fed Letter. Number 234

    Aaronson, Daniel; Park, Kyung-Hong; Sullivan, Daniel

    2007-01-01

    Fewer teenagers are participating in the labor force today than at any point since WWII. At just under 44 percent teen labor force participation is 15 percentage points below its peak in the late 1970s. The authors investigate the long-run decline in the work activity of young adults, and the acceleration of this trend during the last five years.…

  19. Poly[(μ5-5-carboxylatotetrahydrofuran-2,3,4-tricarboxylic acidsodium

    Jie Xu

    2009-11-01

    Full Text Available The search for the novel metal-organic frameworks (MOFs materials using tetrahydrofuran-2,3,4,5-tetracarboxylic acid (THFTCA as a versatile multi-carboxyl ligand, lead to the synthesis and the structure determination of the title compound, [Na(H3THFTCA] or [Na(C8H7O9]n, which was obtained by a solution reaction at room temperature. The ligand is mono-deprotonated, coordinating five sodium ions through one furan oxygen atom and six carboxyl oxygen atoms. The sodium ion exhibits a distorted pentagonal-bipyramidal NaO7 geometry consisting of seven O atoms derived from five surrounding ligands. Two adjacent pentagonal bipyramids share an O—O edge, forming a dinuclear sodium cluster. Finally, these clusters are effectively linked by the carboxyl groups of THFTCA ligands, forming a firm metal organic framework and O—H...O hydrogen bonds contribute to the crystal packing.

  20. 77 FR 234 - Rule Concerning Disclosures Regarding Energy Consumption and Water Use of Certain Home Appliances...

    2012-01-04

    ... CFR Part 305 RIN 3084-AB03 Rule Concerning Disclosures Regarding Energy Consumption and Water Use of... FR 72872) solicited comments on possible disclosures for heating and cooling equipment to help... involve overlapping issues. DOE's comment period ends February 6, 2012. \\1\\ 76 FR 76328 (Dec. 7, 2011)....

  1. 45 CFR 234.70 - Protective payments for the aged, blind, or disabled.

    2010-10-01

    ... selection will be made preferably from the staff of an agency or that part of the agency providing... adequate staff for this purpose. The selection will not include: The executive head of the agency...) Standards will be established for selection of protective payees who are interested in or concerned with...

  2. 49 CFR 234.207 - Adjustment, repair, or replacement of component.

    2010-10-01

    ...) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND..., repair, or replacement of component. (a) When any essential component of a highway-rail grade...

  3. 45 CFR 234.130 - Assistance in the form of institutional services in intermediate care facilities.

    2010-10-01

    ... under the provisions of 42 CFR 449.33 as to a facility's eligibility to receive payments for... services in intermediate care facilities, available income will be applied, first for personal and... of safety and sanitation as are applicable to nursing homes under State law; and (iv)...

  4. Thermoluminescence and 234U/230Th dating investigations of hellenic materials

    Thermoluminescence dating has been applied to pottery and kiln materials from Neolithic and Bronze age sites, using the quartz inclusion method. Uranium disequilibrium dating techniques were used to resolve the age of a skull of an early hominid. (author)

  5. Structure of the Cellulose Synthase Complex of Gluconacetobacter hansenii at 23.4 Å Resolution

    Juan Du; Venkata Vepachedu; Sung Hyun Cho; Manish Kumar; B Tracy Nixon

    2016-01-01

    Bacterial crystalline cellulose is used in biomedical and industrial applications, but the molecular mechanisms of synthesis are unclear. Unlike most bacteria, which make non-crystalline cellulose, Gluconacetobacter hansenii extrudes profuse amounts of crystalline cellulose. Its cellulose synthase (AcsA) exists as a complex with accessory protein AcsB, forming a 'terminal complex' (TC) that has been visualized by freeze-fracture TEM at the base of ribbons of crystalline cellulose. The catalyt...

  6. 49 CFR 234.205 - Operating characteristics of warning system apparatus.

    2010-10-01

    ... limits within which the system is designed to operate. ... 49 Transportation 4 2010-10-01 2010-10-01 false Operating characteristics of warning system...) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY...

  7. Accidental nuclear excursion recuplex operation 234-5 facility: Final medical report

    Fuqua, P. A.

    1962-04-07

    The April 7, 1962 criticality accident involving human exposures was the first to have occurred in any production facility at Hanford. The accidental nuclear excursion did not result in any mechanical damage or spread of contamination. Three employees received over-exposure to gamma and neutron radiation. None were fatally exposed and in each case the over-exposure was recognized promptly. Following an initial period of medical observation and testing, the men were released to work. They continued to be followed clinically. Clinical studies performed were hematological procedures including leukocyte chromosome aberrations, morphologically aberrant blood cells, bone marrow evaluations, blood chemistry determinations, amino acid excretion studies, seminal fluid, urinary gonadotropins and estrogen excretion studies, testicular biopsies and crystalline lens examinations. These studies, along with a brief description of the accident and of the dosimetry, are summarized in this report by those participating in the studies. In view of the dose ranges received in these cases, both the negative and positive findings are considered to be of unusual interest due to the lack of knowledge of effects following human exposures at these levels.

  8. Editorial Revista Contaduría y Administración No. 234

    López Herrera Francisco; Garcia Narvaez Alberto

    2011-01-01

    En un contexto de fuerte competencia, el análisis minucioso y preciso de las relaciones mercado-producto es un elemento indispensable para el diseño de estrategias de mercado que puedan contar con buenas probabilidades de éxito. Johan H. Martínez, Hugo Alberto Rivera R., Carlos E. Maldonado y Rubén Iván A. Mendoza presentan su trabajo de investigación Adquisición de ventajas competitivas mediante la generación de un territorio estratégico. En él se muestra la propuesta mediante la cual dichos...

  9. Study on laser atomic spectroscopy

    Laser atomic spectroscopic study on actinium element has been performed in many areas of spectroscopy. The study on characteristic of atomic vapor has been proceeded for copper atom and the spatial density distribution of copper vapor is measured. This experimental data has been compared with the theoretically calculated data. In spectroscopic experiment, the first and second excited states for actinium element are identified and the most efficient ionization scheme for actinium element is identified. In addition, the corrosion problem for filament material due to the heating of the actinium element has been studied. (Author)

  10. Neutron measurements with miniature fission chambers

    This report analyses the use and qualification of miniature fission chambers for two types of neutron measurements: 1) relative measurements in nuclear power reactors, or nuclear irradiation reactors. We consider the problem of burnable fissile material in detectors, under important neutron exposures and conclude on recommending the use of regenerating neutron detectors. 2) Measurements of integral physical parameters in experimental reactors. This method has been applied to measurements of fission rates in detectors with strong alpha-rays emitter deposits in order to establish standard tables of physical parameters. It has been used in particular for detectors including very radioactive actinium series. After a discussion of the instrumentation choice and data processing, specific to each measurements, we provide results on: 1) the technological and neutron behaviour of regenerating miniature fission chambers, in the swimming pool reactor 'TRITON', under a neutron exposure of 7.1020 n cm-2 and a gamma-rays exposure of 1,5.1011 rads about. The fissile material is 235U and the fertile material 234U. 2) The integral measurements of effective cross sections for 241Am and 238Pu in the experimental reactor 'MINERVE' use for study of problems of fast neutron reactors

  11. Removal of actinium from europium for the determination of specific radioactivity of ultra low-level Eu-152 in a sample exposed to atomic-bomb neutrons in Nagasaki

    Measurements of specific radioactivities of residual neutron-induced radionuclides such as 152Eu and 60Co have been carried out to check the validity of a series of computer calculations employed for the atomic-bomb neutron dosimetry in Hiroshima (exposed to uranium bomb) and Nagasaki (exposed to plutonium bomb). The use of these nuclides for atomic-bomb neutron dosimetry, however, has been limited by the following difficulties: (1) today, these radionuclides are found only at extremely low concentrations in materials exposed to the atomic-bomb and (2) the neutrons that induced these radionuclides were thermal and epithermal, while the neutron dose received in Hiroshima and Nagasaki is attributable to fast neutrons. In order to overcome the first difficulty, we established a chemical procedure to extract Eu and Co from materials exposed to the atomic-bomb, and the chemical procedure has been successful for the materials exposed to atomic-bomb within 1400 m in slant distance from the explosion point. As for Nagasaki, materials exposed in the distances farther than 1200 m have never been subjected to the measurement of residual neutron-induced radionuclides. In this work, determination of specific radioactivity of 152Eu (half-life: 13.542 y) in a sample exposed to Nagasaki atomic-bomb at a distant place from the explosion point was undertaken. But, because of radioactive decay during this ∝60 years since 1945 and long distance from the explosion point, the present specific radioactivity of 152Eu in the sample is extremely low (estimated to be ∝3 x 10-4 Bq-152Eu/mg-Eu), and a serious problem is interferences from daughters of 227Ac (half-life: 21.8 y) in the measurement of ultra low-level radioactivity of 152Eu. Hence, our chemical procedure to obtain Eu-enriched counting source should be improved, and much attention is being denoted to removal of Ac from Eu. (orig.)

  12. 企业“234”班组安全管理的创新实践%Innovative Practice of“234”Team and Group Safety Management

    袁忠军

    2012-01-01

      The paper analyzes how Datang Yantan Hydropower Co., Ltd. to draw lessons from the theory about risk man-agement. Based on four key parts, the management of risky source, process control, contingency plan and continuous im-provement, it also holds that controllable and controlling ways about team and group safe production can be realized, by pro-moting“Two Table, Three Cards and Four Graphs”team management mode.%  文章分析了大唐岩滩水力发电有限责任公司借鉴风险管理理论,围绕风险源头管理、过程控制、应急处置、持续改进4个关键环节,通过推行“两表三卡四图”班组管理模式,实现班组安全生产风险可控、在控、能控的主要路径和方法。

  13. TINGKAT KANDUNGAN UNSUR RADIOAKTIF AIR SUNGAI AYUNG DI DENPASAR BALI

    Dewa Nyoman Alit Ardana

    2012-11-01

    Full Text Available Ayung river is one of the longest rivers in Bali. The upstream of the river is in regency of Bangli, Badung, Buleleng, Tabananand downstream is located in Padang Galak beach, East Denpasar Sub-regency. As the sample of the study, the water of the river wastaken from the stream entering the city of Denpasar. The sample was taken in five different points and for each point was taken twice. Thefirst was taken at 5 p.m, and the second was at 6 a.m. This study aims at finding out the rate of radioactive content of Ayung river water inthe city of Denpasar.The water sample was analyzed in Radiometry Analysis Group of Radiation Physics and environmental research centre andNuclear Technique Development, Jalan Taman Sari 71 Bandung – 40132. The process of counting was conducted in this place in order toknow the rate of the element activities and then identification of elements contens in the sample. The result of the counting and identifyingwas compered with standard grade of radioactivity in the area.The element of identification result and the amount of activity rate found showed that the element were natural radioactiveelements, the content: 40K (Kalium-40, 234Th (Thorium-234, 233Th (Thorium-233, 228Ac (Actinium-288, 114mIn (Indium-114m. Thehighest activity of radioactive elements in each sample point: in E2 point content element 40K with the activity 2.08 Bq/lt, in point A1 234Thwith the activity 16.34 Bq/lt, in point E1 containts 233Th with activity 598.29 Bq/lt, in point E1 and E2 contain 228Ac with the activity939.63 Bq/lt. The height of activity value of the counting and identifying elements was still under the rate of the highest level.The result of the study showed that radioactive elements 40K had the tendency of increasing radioactivity. The same thinghappened to 233Th at the peak of energi 185.00 keV. The content of its radioactive tends to exist in each point of sample point and theactivity tends to increase. Though the rate of

  14. Μελέτη των χαρακτηριστικών της δέσμης νετρονίων και προσδιορισμός παραμέτρων συντονισμού της σύλληψης νετρονίων στο 234U με την μέθοδο της ολικής απορρόφησης, στην πειραματική διάταξη n_TOF του CERN

    Lampoudis, Christos

    At an international level several issues accompany the long-term development of nuclear science and its applications: nuclear waste management, new reactor design, increasingly safety requirements, public acceptance etc. This has triggered many sophisticated R&D activities, such as Accelerator Driven Systems or next generation reactor concepts and enhanced the ongoing effort to expand and improve the existing nuclear data. Among other measurements of special interest, is the neutron capture cross section determination for several isotopes related to the nuclear fuel cycle. This text mainly presents the obtained results from the (n,γ) cross section measurement of 234U that was performed at n_TOF facility (CERN). In detail we describe the main features of the facility, the TAC (Total Absorption Calorimeter) detection arrangement and its performance under specific experimental conditions. Results in the form of R-matrix resonance parameters and cross sections are discussed in parallel with the existing ENDF...

  15. Unilateral pollution control in the Northwest Passage : the Canadian NORDREG regulations in the context of UNCLOS, Article 234

    Raspotnik, Andreas

    2011-01-01

    To safeguard the Canadian Arctic marine environment, Canada established an Arctic marine traffic system, known as the Northern Canada Vessel Traffic Services Zone Regulations (NORDREG). These mandatory regulations require most nongovernmental vessels to report information prior to entering, while operating within and upon exiting Canada’s northern/Arctic waters. Canada asserts that the traffic system is consistent with international law concerning ice-covered areas, in particular with the “Ar...

  16. SU-E-J-234: Application of a Breathing Motion Model to ViewRay Cine MR Images

    Purpose: A respiratory motion model previously used to generate breathing-gated CT images was used with cine MR images. Accuracy and predictive ability of the in-plane models were evaluated. Methods: Sagittalplane cine MR images of a patient undergoing treatment on a ViewRay MRI/radiotherapy system were acquired before and during treatment. Images were acquired at 4 frames/second with 3.5 × 3.5 mm resolution and a slice thickness of 5 mm. The first cine frame was deformably registered to following frames. Superior/inferior component of the tumor centroid position was used as a breathing surrogate. Deformation vectors and surrogate measurements were used to determine motion model parameters. Model error was evaluated and subsequent treatment cines were predicted from breathing surrogate data. A simulated CT cine was created by generating breathing-gated volumetric images at 0.25 second intervals along the measured breathing trace, selecting a sagittal slice and downsampling to the resolution of the MR cines. A motion model was built using the first half of the simulated cine data. Model accuracy and error in predicting the remaining frames of the cine were evaluated. Results: Mean difference between model predicted and deformably registered lung tissue positions for the 28 second preview MR cine acquired before treatment was 0.81 +/− 0.30 mm. The model was used to predict two minutes of the subsequent treatment cine with a mean accuracy of 1.59 +/− 0.63 mm. Conclusion: Inplane motion models were built using MR cine images and evaluated for accuracy and ability to predict future respiratory motion from breathing surrogate measurements. Examination of long term predictive ability is ongoing. The technique was applied to simulated CT cines for further validation, and the authors are currently investigating use of in-plane models to update pre-existing volumetric motion models used for generation of breathing-gated CT planning images

  17. Crystal structure of (E-5,5-dimethyl-2-[3-(4-nitrophenylallylidene]cyclohexane-1,3-dione

    Jae Kyun Lee

    2015-07-01

    Full Text Available In the title compound, C17H17NO4, the cylohexane-1,3-dione ring adopts an envelope conformation with the dimethyl-subsituted C atom as the flap. Its mean plane is inclined to the benzene ring by 7.99 (19°. The molecule has a trans conformation about the bridging C=C bonds of the allyidene chain. In the crystal, molecules are linked via pairs of C—H...O hydrogen bonds, forming inversion dimers. The dimers are linked by further C—H.·O hydrogen bonds, forming sheets lying parallel to (10-1.

  18. Contributions to Th-230/U-234 dating of speleothems; comparison of the results with those of other absolute dating methods

    Calcite speleothems, e.g. stalagmites, have been investigated by α-spectrometry using Si-surface boundary layer detectors after radiochemical separation. The findings are compared with those of other physical/chemical/nuclear physics techniques. (HP)

  19. How information technology can help sustainability and aid in combating global warming[ACI SP-234-44

    Kondratova, I.L.; Goldfarb, I. [National Research Council of Canada, Ottawa, ON (Canada). Inst. for Information Technology

    2006-07-01

    This presentation addressed the need to reduce the environmental impact of concrete production. Unit based carbon dioxide emissions in cement production vary from 0.73 to 0.99 kg carbon dioxide per kg of cement. As such, annual cement manufacturing contributes significantly to global warming. The challenge facing the concrete industry regarding sustainable growth was discussed. It was suggested that sustainable development in the cement industry can be accomplished not only by making an industry wide shift to conservation of energy and materials, but by making greater use of the Internet for information technology on sustainable construction materials such as lightweight aggregates and lightweight concrete. The paper outlined the evolution of various methods of disseminating research results on the durability of concrete at the United States Army Corps of Engineers Treat Island marine exposure site. The results indicated that structural lightweight and semi-lightweight concrete provides long-term durability in a marine environment. It was noted that knowledge utilization includes technology transfer, information dissemination and utilization, research utilization, innovation, and organizational change. The paper emphasized the use of web portals as a tool for improving access to practical information on a full range of sustainable industry practices, products and resources. These tools allow side-by side comparison of testing results for different concrete mixtures and support decision-making on the choice of environmentally sound and durable concrete. The authors demonstrated by advantages of using modern information technology tools by suggesting that with the development of a full scale Portal, the Expanded Shale, Clay, and Slate Institute (ESCSI) could become a global source of credible information and expertise in the area of lightweight concrete. As such ESCSI could be in a position to influence innovation and technology transfer to the industry. The paper presented the conceptual model and identified business needs. 36 refs., 4 figs.

  20. Postsecondary and Labor Force Transitions among Public High School Career and Technical Education Participants. Issue Tables. NCES 2011-234

    Bersudskaya, Vera; Chen, Xianglei

    2011-01-01

    Career and technical education (CTE) is a significant component of high school education. For the last several decades, more than 90 percent of public high school graduates have earned at least some credits in CTE, with graduates from the class of 2005 earning an average of 4.0 CTE credits (Hudson and Laird 2009; Levesque 2003; Levesque et al.…

  1. Diiodo{N,N´-bis(2,3,4-trimethoxybenzaldehyde)-ethylenediimine}mercury(II): synthesis and crystal structure

    Khalaji, A.D.; Fejfarová, Karla; Dušek, Michal

    2013-01-01

    Roč. 39, č. 1 (2013), s. 68-71. ISSN 1070-3284 Institutional support: RVO:68378271 Keywords : mercury (II) * Schiff base * single crystal * structure analysis Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.629, year: 2013

  2. Outcome in patients transferred for percutaneous coronary intervention (a national registry of myocardial infarction 2/3/4 analysis).

    Shavelle, David M; Rasouli, M Leila; Frederick, Paul; Gibson, C Michael; French, William J

    2005-11-01

    Hospital transfer is associated with delays in performance of primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction. Given the limited number of interventional centers in the United States, the transfer of patients is widely practiced. We compared the outcome of patients who were transferred for primary PCI and determined whether prolonged door-to-balloon times were associated with increased mortality. Patients who presented within 12 hours with ST-segment elevation myocardial infarction and underwent transfer for primary PCI were identified from the National Registry of Myocardial Infarction database (NRMI databases 2, 3, and 4, n = 7,133). The short-term outcome of those who received early (2 hours) using multivariate logistic regression analyses and propensity score methods. The door-to-balloon time for the early PCI group compared with the delayed PCI group was 99 +/- 16 versus 264 +/- 178 minutes, respectively (p <0.0001). The early PCI group had less recurrent ischemia and angina (5.8% vs 10.1%, p <0.001), less cardiogenic shock (5.1% vs 8.9%, p <0.001), and shorter length of hospital stay (4.4 +/- 3.5 vs 5.4 +/- 4.7 days, p <0.001). In-hospital mortality was lower for the early PCI group than for the delayed PCI group (2.7% vs 6.2%, p < 0.001; entire cohort 5.7%). Comparison of patients matched on propensity score (n = 993) showed that mortality was lower in the early than in the delayed PCI group (2.6% vs 4.6%, p = 0.014, c-statistic 0.67). In conclusion, <4% of patients who received PCI were treated within the recommended guideline of < 120 minutes by the American College of Cardiology/American Heart Association. Door-to-balloon times <2 hours in patients who undergo transfer for PCI is associated with a significant decrease in short-term mortality, which suggests that efforts must be made to decrease transfer delays. PMID:16253587

  3. Generator method of 225Ac production without a carrier for nuclear medicine

    The two-steps isotope generator scheme of 225Ac production from 229Th has been developed. The first step is used for separation of thorium, actinium, radium and daughter decay products (DDP), and removals of parent radionuclide. The second step provides additional separation of actinium from traces of radium and DDP, and conversion of actinium in the nitrate form. The chosen solutions provide optimal conditions for carry out of process. The yield of the 225Ac was 99.9% at minimal losses of parent 229Th (less than 0.1%)

  4. An aerial radiological survey of the Nevada Test Site

    A team from the Remote Sensing Laboratory conducted an aerial radiological survey of the US Department of Energy's Nevada Test Site including three neighboring areas during August and September 1994. The survey team measured the terrestrial gamma radiation at the Nevada Test Site to determine the levels of natural and man-made radiation. This survey included the areas covered by previous surveys conducted from 1962 through 1993. The results of the aerial survey showed a terrestrial background exposure rate that varied from less than 6 microroentgens per hour (mR/h) to 50 mR/h plus a cosmic-ray contribution that varied from 4.5 mR/h at an elevation of 900 meters (3,000 feet) to 8.5 mR/h at 2,400 meters (8,000 feet). In addition to the principal gamma-emitting, naturally occurring isotopes (potassium-40, thallium-208, bismuth-214, and actinium-228), the man-made radioactive isotopes found in this survey were cobalt-60, cesium-137, europium-152, protactinium-234m an indicator of depleted uranium, and americium-241, which are due to human actions in the survey area. Individual, site-wide plots of gross terrestrial exposure rate, man-made exposure rate, and americium-241 activity (approximating the distribution of all transuranic material) are presented. In addition, expanded plots of individual areas exhibiting these man-made contaminations are given. A comparison is made between the data from this survey and previous aerial radiological surveys of the Nevada Test Site. Some previous ground-based measurements are discussed and related to the aerial data. In regions away from man-made activity, the exposure rates inferred from the gamma-ray measurements collected during this survey agreed very well with the exposure rates inferred from previous aerial surveys

  5. Alpha-emitting isotopes and chromium in a coastal California aquifer

    Densmore, Jill N.; Izbicki, John A.; Murtaugh, Joseph M.; Swarzenski, Peter W.; Bullen, Thomas D.

    2014-01-01

    The unadjusted 72-h gross alpha activities in water from two wells completed in marine and alluvial deposits in a coastal southern California aquifer 40 km north of San Diego were 15 and 25 picoCuries per liter (pCi/L). Although activities were below the Maximum Contaminant Level (MCL) of 15 pCi/L, when adjusted for uranium activity; there is concern that new wells in the area may exceed MCLs, or that future regulations may limit water use from the wells. Coupled well-bore flow and depth-dependent water-quality data collected from the wells in 2011 (with analyses for isotopes within the uranium, actinium, and thorium decay-chains) show gross alpha activity in marine deposits is associated with decay of naturally-occurring 238U and its daughter 234U. Radon activities in marine deposits were as high as 2230 pCi/L. In contrast, gross alpha activities in overlying alluvium within the Piedra de Lumbre watershed, eroded from the nearby San Onofre Hills, were associated with decay of 232Th, including its daughter 224Ra. Radon activities in alluvium from Piedra de Lumbre of 450 pCi/L were lower than in marine deposits. Chromium VI concentrations in marine deposits were less than the California MCL of 10 μg/L (effective July 1, 2014) but δ53Cr compositions were near zero and within reported ranges for anthropogenic chromium. Alluvial deposits from the nearby Las Flores watershed, which drains a larger area having diverse geology, has low alpha activities and chromium as a result of geologic and geochemical conditions and may be more promising for future water-supply development.

  6. Determination of 234Pa(n,f), 239Np(n,f) and 240Np(n,f) reaction cross sections by hybrid surrogate ratio method

    The neutron induced fission (n,f) cross section data are important for their applications in nuclear energy, national security and nuclear astrophysics. Unfortunately for large number of nuclear species from actinide region, the relevant data cannot be measured directly in laboratory or reliably predicted by calculations. The (n,f) cross section data on many actinide nuclei which are produced in the nuclear fuel cycles such as Pa in Th-U fuel cycle or Np, Cm, Pu, Am in U-Pu fuel cycle, are not readily available. The direct measurement of (n,f) cross section on these unstable isotopes is particularly affected since the relevant nuclei are difficult to produce by present day experimental techniques or too short lived to serve as target. Calculations are highly nontrivial since they typically require a thorough understanding of both direct and statistical mechanism and detailed knowledge of the nuclear structure involved

  7. Accurate measurements of fission-fragment yields in $^{234,235,236,238}$U(γ,f) with the SOFIA set-up

    Chatillon A.; Taïeb J.; MARTIN J. - F.; Pellereau E.; Boutoux G.; Gorbinet T.; Grente L.; Bélier G.; Laurent B.; Alvarez-Pol H.; Ayyad Y.; Benlliure J.; Caamaño M.; Audouin L.; Casarejos E.

    2015-01-01

    SOFIA (Studies On Fission with Aladin) is a new experimental set-up dedicated to accurate measurement of fission-fragments isotopic yields. It is located at GSI, the only place to use inverse kinematics at relativistic energies in order to study the (γ,f) electromagnetic-induced fission. The SOFIA set-up is a large-acceptance magnetic spectrometer, which allows to fully identify both fission fragments in coincidence on the whole fission-fragment range. This paper will report on fission yields...

  8. Preparation of Ca-alginate bio-polymer beads and investigation of their decorporation characteristics for 85Sr, 238U and 234Th by in vitro experiments

    The aim of this work was to investigate whether Ca-alginate bio-polymer beads (CaABBs) can be used to reduce the bioavailability of radionuclides in the gastrointestinal tract of humans. The uptake of strontium, uranium and thorium from a simulated gastrointestinal system was studied by in vitro techniques using CaABBs. This agent was prepared from Na-alginate through cross-linking with divalent calcium ions according to the egg-box model. The effects of process variables such as pH of the gastrointestinal juice, incubation time and solid-to-solution ratio for the removal of radionuclides from the gastrointestinal juice were investigated. The results suggest that CaABBs are a potent material for reducing the bioavailability of radionuclides with a high uptake efficiency in the gastrointestinal tract.Copy; Author 2012. Published by Oxford Univ. Press. All rights reserved. (authors)

  9. Moderator analysis of the Wolsong Units 2/3/4 for the case of 35% RIH breaks with a loss of ECC injection using CFX-4.4

    A 3-D CFD model was developed for the transient simulation of the moderator circulation inside the Calandria vessel, using a commercial code CFX-4.4. To reduce the discretization errors in the reflector region, a set of butterfly-shaped grid structures were generated and used. The porous media approach was applied for the core region containing 380 Calandria tubes. A 3-dimensional hydraulic model for the porous core region has been developed based on the empirical pressure drop correlations. The transient moderator analysis was performed for the 35% RIH(Reactor Inlet Header) break with a loss of ECC(Emergency Core Cooling) injection, which gives the largest heat load to the moderator out of all the DBA's. During the initial 1200 seconds in the LOCA transient, the local subcooling near any PT/CT contact location does not go down below the minimum subcooling margin of 28oC, the experimentally derived threshold. It is concluded that film boiling on the Calandria tube surfaces would not occur during the selected LOCA scenario and thus the fuel channel integrity is maintained in the CANDU-6 reactor. (author)

  10. Measurement of uranium in small quantities in phosphates by use of γ-ray spectrometry and the 1001 keV peak of 234mPa

    Phosphates, naturally containing trace amounts of uranium, were examined using direct γ-ray spectrometry. Both normal and Compton-suppressed counting modes were utilized. The 1001 keV photo peak of the second daughter of 238U was chosen because of its isolation from other, potentially interfering peaks. The findings suggest that with the aid of Compton suppression, it is possible to quantify low uranium levels in phosphates using samples sizes of order 10 grams within an accuracy of 5%. The uranium content was determined in several sample types and was found to range from 60±4 to 70±8 μg/g, depending on the sample composition. This investigation also considered the effects of sample size, counting time, and counting technique as sources of precision maximization. This work has shown that only a small amount of phosphate is needed to determine the constituent concentration, instead of the standard several hundred grams of material. (author)

  11. Fission barrier determinations and fragment angular correlations for the 244Pu, 242Pu, 240U, 238U, 234Th, and 232Th compound nuclei from (t, pf) reactions

    Fission probabilities and the angular distribution of the fission fragments have been measured for six even-even compound nuclear systems using the (t, pf) reaction. Angular correlations of fission fragments obtained in these experiments provide information about the low-lying collective excitations or transition states at the fission barrier. The (t, p) reaction in particular leads to neutron-rich residual nuclei unobtainable by other methods. The absence of spin coupling for (t, p) reactions on even-even targets provides angular distributions with well defined structure in the region of the fission barrier. The experimental data were obtained using an 18-MeV triton beam on targets of 242Pu, 240Pu, 238U, 236U, 232Th and 230Th at Los Alamos Van-de-Graaff accelerator facility. Outgoing protons were detected at 140 deg relative to the incident triton beam. Excitation energies ranging from 3.0 to 9.0 MeV were obtained in these experiments. Fission fragment angular distributions were measured at 24 angles from 0 deg to 140 deg relative to the kinematic recoil angle. The data were fitted to a series of even Legendre polynomials W(θ) = A0 [1 + ΣL gL PL (cos θ)] and the coefficients g2 through g12 and A0 were determined as a function of excitation energy. The fission probability Pf was obtained from the ratio of A0 to the (t, p) cross-section for the target nucleus. The results exhibit well defined structure in the angular coefficients which correlates with structure in the fission probability for most of the nuclei studied. In an attempt to interpret this observed structure the experimentally determined fitting parameters Pf and g are compared with calculated results of a microscopic model. This model takes into consideration the penetrability and angular dependence of fission through each member of the various transition bands at the saddle point and appropriately sums the results for comparison with the data. The effects of barrier penetration through a two-peaked deformation potential are explored in this analysis. This survey of the fission properties of several nuclei indicates some general trends relating the saddle point deformation to the character of the transition level structure. (author)

  12. A study on possible use of Urtica dioica (common nettle) plants as uranium (234U, 238U) contamination bioindicator near phosphogypsum stockpile

    Olszewski, Grzegorz; Boryło, Alicja; Skwarzec, Bogdan

    2015-01-01

    The aim of this study was to determine uranium concentrations in common nettle (Urtica dioica) plants and corresponding soils samples which were collected from the area of phosphogypsum stockpile in Wiślinka (northern Poland). The uranium concentrations in roots depended on its concentrations in soils. Calculated BCF and TF values showed that soils characteristics and air deposition affect uranium absorption and that different uranium species have different affinities to U. dioica plants. The...

  13. Fusion hybrids for generation of advanced (231Pa+232U+233U+234U)-fuel in closed (U-Pu-Th)-fuel cycle

    Technology of controlled thermonuclear fusion (CTF) is traditionally regarded as a practically inexhaustible energy source. However, development, mastering, broad deployment of fast breeder reactors and closure of nuclear fuel cycle (NFC) can also extend fuel base of nuclear power industry (NPI) up to practically unlimited scales. Under these conditions, it seems reasonable to introduce into a circle of the CTF-related studies the works directed towards solving some principal problems which can appear in a large-scale NPI in closed NFC. The first challenge is a large scale of operations in NFC back-end that should be reduced by achieving substantially higher fuel burn-up in power nuclear reactors. The use of 231Pa-232Th-232U-233U fuel in light-water reactor (LWR) opens a possibility of principle to reach very high (about 30% HM) or even ultra-high fuel burn-up. The second challenge is a potential unauthorized proliferation of fissionable materials. As is known, a certain remarkable quantity of 232U being introduced into uranium fraction of nuclear fuel can produce a serious barrier against switching the fuel over to non-energy purposes. Involvement of hybrid thermonuclear reactors (HTR) into NPI structure can substantially facilitate resolving these problems. If HTR will be involved into NPI structure, then main HTR mission consists not in energy generation but in production of nuclear fuel with a certain isotope composition. The present paper analyzes some neutron-physical features in production of advanced nuclear fuels in thorium HTR blankets. The obtained results demonstrated that such a nuclear fuel may be characterized by very stable neutron-multiplying properties during full LWR operation cycle and by enhanced proliferation resistance too. The paper evaluates potential benefits from involvement of HTR with thorium blanket into the international closed NFC. (author)

  14. 14 CFR 13.234 - Petition to reconsider or modify a final decision and order of the FAA decisionmaker on appeal.

    2010-01-01

    ... AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PROCEDURAL RULES INVESTIGATIVE AND ENFORCEMENT... prospective witnesses and authenticated documents that would be introduced in support of the new material....

  15. Silicene versus two-dimensional ordered silicide: atomic and electronic structure of Si-(√19×√19)R23.4◦/Pt(111)

    Švec, Martin; Hapala, Prokop; Ondráček, Martin; Merino, P.; Blanco-Rey, M.; Mutombo, Pingo; Vondráček, Martin; Polyak, Yaroslav; Cháb, Vladimír; Martín Gago, J.A.; Jelínek, Pavel

    2014-01-01

    Roč. 89, č. 20 (2014), "201412-1"-"201412-5". ISSN 1098-0121 R&D Projects: GA MŠk(CZ) LM2011029; GA ČR(CZ) GA14-02079S Grant ostatní: SAFMAT(XE) CZ.2.16/3.1.00/22132 Institutional support: RVO:68378271 Keywords : silicene * silicide * surface alloy * STM * photoemission spectroscopy * ARUPS * DFT Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.736, year: 2014

  16. Oral conditions in patients with Sjögren’s Syndrome: a Systematic Review - doi:10.5020/18061230.2006.p234

    Marina Fernandes de Sena

    2012-01-01

    Full Text Available The aim of this study was to investigate through a systematic review, the oral manifestations of Sjögren’s syndrome. It had as research sources: manual searches in publications, sites and electronic data bases such as MEDLINE, LILACS and BBO. As its inclusion criteria: cross-sectional, case-control and cohort studies which data collection was done by means of clinical indexes for dental caries, periodontal disease and oral mucosa. The selected idioms were: Portuguese, English and Spanish; in the period of 1990 to 2003. Searching strategies used included the following words: Sjögren, dmf, caries, decay, periodontal, plaque and gingivitis. Thirteen studies were selected, one of these in Spanish and the others in English. All delineations were case-control, 54% of these aimed at evaluating the relationship between patients with the syndrome and caries presence, 85% with periodontal disease and 32% relating to the alterations of oral mucosa. The analyzed studies showed that the main symptom of Sjögren’s syndrome is xerostomy and that exist a slight association between syndromic patients and dental caries index and some alterations of oral mucosa and a weak association with periodontal diseases.

  17. Gamma-Ray Emission Spectra as a Constraint on Calculations of 234,236,238U Neutron-Capture Cross Sections

    Ullmann, John Leonard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kawano, Toshihiko [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bredeweg, Todd Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Baramsai, Bayarbadrakh [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Couture, Aaron Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Haight, Robert Cameron [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jandel, Marian [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mosby, Shea Morgan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); O' Donnell, John M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rundberg, Robert S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Vieira, David J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wilhelmy, Jerry B. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Becker, John A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wu, Ching-Yen [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Krticka, Milan [Charles Univ., Prague (Czech Republic)

    2015-05-28

    Neutron capture cross sections in the “continuum” region (>≈1 keV) and gamma-emission spectra are of importance to basic science and many applied fields. Careful measurements have been made on most common stable nuclides, but physicists must rely on calculations (or “surrogate” reactions) for rare or unstable nuclides. Calculations must be benchmarked against measurements (cross sections, gamma-ray spectra, and <Γγ>). Gamma-ray spectrum measurements from resolved resonances were made with 1 - 2 mg/cm2 thick targets; cross sections at >1 keV were measured using thicker targets. The results show that the shape of capture cross section vs neutron energy is not sensitive to the form of the strength function (although the magnitude is); the generalized Lorentzian E1 strength function is not sufficient to describe the shape of observed gamma-ray spectra; MGLO + “Oslo M1” parameters produces quantitative agreement with the measured 238U(n,γ) cross section; additional strength at low energies (~ 3 MeV) -- likely M1-- is required; and careful study of complementary results on low-lying giant resonance strength is needed to consistently describe observations.

  18. Design procedures for the use of composites in strengthening of reinforced concrete structures state-of-the-art report of the RILEM Technical Committee 234-DUC

    Sena-Cruz, José

    2016-01-01

    This book analyses the current knowledge on structural behaviour of RC elements and structures strengthened with composite materials (experimental, analytical and numerical approaches for EBR and NSM), particularly in relation to the above topics, and the comparison of the predictions of the current available codes/recommendations/guidelines with selected experimental results. The book shows possible critical issues (discrepancies, lacunae, relevant parameters, test procedures, etc.) related to current code predictions or to evaluate their reliability, in order to develop more uniform methods and basic rules for design and control of FRP strengthened RC structures. General problems/critical issues are clarified on the basis of the actual experiences, detect discrepancies in existing codes, lacunae in knowledge and, concerning these identified subjects, provide proposals for improvements. The book will help to contribute to promote and consolidate a more qualified and conscious approach towards rehabilitation...

  19. Biological evaluation of the prototype standing tree debarking system (STDS) used for direct control of mountain pine beetle in lodgepole pine. FRDA report No. 234

    Whitney, H.S.; Safranyik, L.; Moulson, D.C.

    1995-12-31

    The standing tree debarking system (STDS) consists of a tree-climbing delimber/debarker machine and a hand-held debarking machine. The tree-climbing machine is powered by a chain saw engine which, through a hydraulic system, operates a delimbing saw on ascent and a debarker on descent. The hand-held machine consists of a debarking head that replaces the cutter on a gasoline-powered brush saw. Prototypes of the STDS have been developed for mechanical removal of bark from standing lodgepole pine trees that have been attacked by the mountain pine beetle (Dendroctonus ponderosae). This paper presents results of work conducted to ascertain the potential effectiveness of the STDS (the degree of bark disruption required to prevent mountain pine beetle from producing increased numbers of new beetles in infested trees of various size), the degree of bark disruption by the STDS, and brood survival in patches of bark remaining after STDS treatment.

  20. 49 CFR 234.247 - Purpose of inspections and tests; removal from service of relay or device failing to meet test...

    2010-10-01

    ... TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY AND STATE ACTION PLANS Maintenance, Inspection, and Testing... are required at highway-rail grade crossings located on in service railroad tracks and shall be...

  1. [N,N´-Bis(2,3,4-trimethoxybenzylidene)ethane-1,2-diamine-κ.sup.2./sup.N,N´]dibromidomercury(II)

    Khalaji, A.D.; Dušek, Michal; Fejfarová, Karla

    2012-01-01

    Roč. 68, Part 8 (2012), "m1044"-"sup7". ISSN 1600-5368 Grant ostatní: AVČR(CZ) Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : single crystal X-ray diffraction * structure analysis * mercury * twinning * Schiff bases Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.347, year: 2011

  2. The experimental study on protective effects and mechanisms of chelating agents of catechols amino carboxylic acid for radiation injury induced by actimides(Th-234)

    The decorporative efficacy and antioxidative action of prompt and delayed consecutive administration of catecholicpolyaminopolycarboxylate ligands, 7601 and 9501 for radiothorium in mice were investigated. DTPA and Vitamin E were used as positive controls. The competitive abilities of 7601 and 9501 to mobilize the thorium with BSA were studied. Their inhibition effects on superoxide anionas radicals were measured with electron spin resonance. The results showed that 7601 and 9501 are able to effectively prevent the internal radiation injury induced radiothorium, attributing to their double functions of pronounced removal effectiveness and antioxidative action. Their protective effects were better than DTPA and Vitamin E. The mechanisms of protective effects of 7601 and 9501 for internal radiation injury was close related to competitive ability of chelating agent to chelate the thorium with BSA and oxygen free radical scavenging activities

  3. Operations Support of Phase 2 Integrated Demonstration In Situ Bioremediation. Volume 2, Final report: Data in tabular form, Disks 2,3,4

    Hazen, T.C. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1993-09-01

    This document consists solely of data acquired during phase 2 of the integrated demonstration project concerning in situ bioremediation performed at the Savannah River Site, Aiken, South Carolina. The data is presented in tabular form.

  4. SU-E-T-234: Modulated Photon Radiotherapy (XMRT):The Impact of Incorporating Energy Modulation Into Intensity Modulated Radiotherapy (IMRT) Optimization

    McGeachy, P; Khan, R [University of Calgary, Calgary, Alberta (Canada)

    2014-06-01

    Purpose: To develop a new radiotherapy plan optimization technique that, for a given organ geometry, will find the optimal photon beam energies and fluences to produce a desirable dose distribution. This new modulated (both in energy and fluence) photon radiotherapy (XMRT) was compared with intensity modulated radiotherapy (IMRT) for a simple organ geometry. Methods: The XMRT optimization was formulated using a linear programming approach where the objective function is the mean dose to the healthy organs and dose-point constraints were assigned to each organ of interest. The organ geometry consisted of a target, two organs at risk (OARs), and normal tissue. A seven-equispaced-coplanar beam arrangement was used. For conventional IMRT, only 6 MV beams were available, while XMRT was optimized using 6 and 18 MV beams. A prescribed dose (PD) of 72 GY was assigned to the target, with upper and lower bounds of 110% and 95% of the PD, respectively. Both OARs were assigned a maximum dose of 64 Gy, while the normal tissue was assigned a maximum dose of 66 Gy. A numerical solver, Gurobi, generated solutions for the XMRT and IMRT problems. The dose-volume histograms from IMRT and XMRT solutions were compared. Results: The maximum, minimum, mean, and homogeneity of the dose to the target were comparable between IMRT and XMRT. Though IMRT had improved dose conformity relative to XMRT, XMRT reduced the mean dose to both OARs by more than 1 Gy. For normal tissue, an increase of 5 Gy in mean dose and 27 percent in integral dose was seen for IMRT relative to XMRT. Conclusion: This work demonstrates the benefits of simultaneously modulating photon beam energy and fluence using our XMRT approach in a given phantom geometry. While target coverage was comparable, dose to healthy structures was reduced using XMRT.

  5. Ethyl 2-(3,4-dimethyl-5,5-dioxo-1H,4H-benzo[e]pyrazolo[4,3-c][1,2]thiazin-1-ylacetate

    Sana Aslam

    2012-10-01

    Full Text Available In the title molecule, C15H17N3O4S, the heterocyclic thiazine ring adopts a twist-boat conformation, which differs from that in related compounds, with adjacent S and C atoms displaced by 0.981 (4 and 0.413 (5 Å, respectively, on the same side of the mean plane formed by the remaining ring atoms. The mean plane of the benzene ring makes a dihedral angle of 23.43 (14° with the mean plane of the pyrazole ring. In the crystal, molecules are connected by weak C—H...O hydrogen bonds to form a three-dimensional network. The H atoms of the methyl group attached to the pyrazole ring were refined over six sites with equal occupancies.

  6. Natural and manmade radionuclides in the environment

    Human beings are constantly exposed to ionizing radiations in nature. These natural background radiations have both terrestrial and extraterrestrial origin. The extraterrestrial radiation is largely due to cosmic rays. Earth's atmosphere is continuously bombarded with high energy cosmic rays which originate from our own cosmos. The primary interaction of high energy cosmic rays with the atmosphere produces a number of secondary radiations in the form of neutrons and protons of various energies which in turn produce a variety of radionuclides through nuclear reactions with nitrogen, oxygen and other nuclei in atmosphere and through other processes. In addition, sub-atomic particles like mesons, muons and electrons are also produced. The radiation dose rate in India at sea level due to cosmic rays is 32 nGy h-1. The naturally occurring terrestrial radionuclides can be divided into those that occur singly and those that are components of the three chains of radioactive series namely, the Uranium series, the Thorium series and the Actinium series. Among the singly occurring radionuclides Potassium-40 with half life of 1.3x109 years is the most prominent and is widely distributed in rocks and soil. 40K is fairly abundant, forming about 0.012% of' total potassium, and is widely distributed in environmental matrix and it is an essential element for most life forms. Uranium-238 and Thorium 232 and their daughters generate the bulk of natural ionising radiation in our environment. Uranium-238 is the head of a series of 15 principal radionuclides, It is the most abundant (99.28%) isotope of natural uranium and is found in all rocks and soil in varied concentration. The radionuclide 238U decays through 234U and 230Th to 226Ra, which has a relatively long half life of 1628 years. 226Ra and its daughter products constitute an important part of natural radiation exposure. About 98% of the external dose from uranium series is delivered by 226Ra and its daughter products

  7. Use of gamma-ray spectrometry for analysis of Uranium isotopic composition in soil of Iran

    The use of depleted uranium (DU) in various weaponry and ammunition during the Iraq war in April, 2003 caused serious concern in Iran over possible uranium contamination of the Iran environment and consequently long health effect. After a shell explosion, uranium is discharged by the fire in the air in the form of oxidized particles and can be dispersed within a radius of several kilometers. Gamma-ray spectrometry was used to determine uranium concentration in soil samples collected from 8 sites in Iranian sectors of Iraq border. All soil samples were dried ,gently grounded and passed through a 2 mm sieve. Three hundred grams of each sample were placed in plastic container and sealed for at least 20 days to allow equilibrium in uranium, thorium and actinium series. Gamma-ray intensities were measured with 40% HPGe (CANBERRA) detector. The detector was shielded by 10 cm lead on all sides with cadmium-copper in inner sides. The system is equipped with software for data acquisition and analyzing. The counting time was 6x104 seconds and background spectra were also collected for the same period of time. The concentrations of 238U assessed from 63.3 keV and 92.4 keV emission of its first daughter nuclide, 234Th. To assess the isotopic ratio of 238U/235 U, secular equilibrium was ensured and the concentration of 235U under the 186 keV was deduced. The 226Ra was determined through the 295 keV and 352 keV gamma-rays of 214Pb. The concentrations of 238U and activity ratio of 238U/235U is given. The average of measurement activity ratio is 21,very close to the value of 21.5 for natural uranium, while the activity ratio of DU can be as high as 76.9. The 238U activity ranges within typically accepted levels from 14-33 Bq kg-1, while the typical range given by UNSCEAR (1988) for different soil samples is 10 to 50 Bq kg-1. The analysis of eight surface soil samples of Iranian sites of Iraq border, showed that uranium isotopes are in their natural abundances

  8. Alpha-emitting isotopes and chromium in a coastal California aquifer

    Highlights: • Alluvium in Piedra de Lumbre basin higher radionuclides likely from natural Th. • Natural uranium decay-chain isotopes, including Ra, present in marine deposits. • Marine deposits also contain low concentrations of chromium. • Radionuclides and chromium concentrations lower in alluvium in the Las Flores basin. - Abstract: The unadjusted 72-h gross alpha activities in water from two wells completed in marine and alluvial deposits in a coastal southern California aquifer 40 km north of San Diego were 15 and 25 picoCuries per liter (pCi/L). Although activities were below the Maximum Contaminant Level (MCL) of 15 pCi/L, when adjusted for uranium activity; there is concern that new wells in the area may exceed MCLs, or that future regulations may limit water use from the wells. Coupled well-bore flow and depth-dependent water-quality data collected from the wells in 2011 (with analyses for isotopes within the uranium, actinium, and thorium decay-chains) show gross alpha activity in marine deposits is associated with decay of naturally-occurring 238U and its daughter 234U. Radon activities in marine deposits were as high as 2230 pCi/L. In contrast, gross alpha activities in overlying alluvium within the Piedra de Lumbre watershed, eroded from the nearby San Onofre Hills, were associated with decay of 232Th, including its daughter 224Ra. Radon activities in alluvium from Piedra de Lumbre of 450 pCi/L were lower than in marine deposits. Chromium VI concentrations in marine deposits were less than the California MCL of 10 μg/L (effective July 1, 2014) but δ53Cr compositions were near zero and within reported ranges for anthropogenic chromium. Alluvial deposits from the nearby Las Flores watershed, which drains a larger area having diverse geology, has low alpha activities and chromium as a result of geologic and geochemical conditions and may be more promising for future water-supply development

  9. I. The metabolic properties of plutonium and allied materials

    Hamilton, J.G.

    1948-05-24

    This report on the metabolic properties of plutonium and related radioactive materials presents experimental information in the following areas: radioautographic studies; tracer studies (with tables of accumulation in tissues) of actinium, radio-zirconium, technetium, radio-rubidium, radio-germanium, beryllium, and cadmium; decontamination and bone metabolism studies; and radio-chemical isolation.

  10. Dicty_cDB: Contig-U11222-1 [Dicty_cDB

    Full Text Available ccgatatagcaaacgtttgtaatgaaggtgcattggttgccgcaaga 234 ||||||||||||||||||||||||||||||||...|||||||||||||||||||||||||||| Sbjct: 175 ggtttcagtggtgccgatatagcaaacgtttgtaatgaaggtgcattggttgccgcaaga... 234 Query: 235 aaagatgcaacctctgccaatttcgatcactttgaagaggcaatcgagagagtattggtt 294 ||||||||...|||||||||||||||||||||||||||||||||||||||||||||||||||| Sbjct: 235 aaagatgcaacctctgccaatttcgatcactttgaagaggcaatcgagagagtattg...acgtactatcgtagctcatcat 354 Query: 355 gaagctggtcatgctgttgttggttggttccttgaacatactgatccacttc

  11. Nontypical iodine–halogen bonds in the crystal structure of (3 E )-8-chloro-3-iodomethylidene-2,3-dihydro-1,4-oxazino[2,3,4- ij ]quinolin-4-ium triiodide

    Bartashevich, E.V.; Batalov, V.I.; Yushina, I.D.; Stash, A.I.; Chen, Y.S. (South Ural); (Karpov); (UC)

    2016-04-29

    Two kinds of iodine–iodine halogen bonds are the focus of our attention in the crystal structure of the title salt, C12H8ClINO+·I3-, described by X-ray diffraction. The first kind is a halogen bond, reinforced by charges, between the I atom of the heterocyclic cation and the triiodide anion. The second kind is the rare case of a halogen bond between the terminal atoms of neighbouring triiodide anions. Lastly, the influence of relatively weakly bound iodine inside an asymmetric triiodide anion on the thermal and Raman spectroscopic properties has been demonstrated.

  12. Comparison of 230Th/234U Dating Results Obtained on Fossil Mollusk Shell from Morocco and Fossil Coral Samples from Egypt. Research of Methodological Criteria to Valid the Measured Age

    Radiochemical ages of 126 unrecrystallized coral samples from the Egyptian shoreline and 125 fossil mollusk shell samples from the Atlantic coast of Moroccan High Atlas are discussed.For corals, the obtained ages are in good agreement with the ages reported previously on urecristallized corals except in some sites where some samples are affected by a cementation of younger aragonite.For mollusk shells, the obtained ages are in the most of cases, rejuvenated.This rejuvenation is due eventually to a post-incorporation of secondary uranium that is responsible of the wide dispersion of apparent ages of mollusk shells.

  13. Entwicklung und Validierung einer kombinierten Schnellanalysenmethode zur Bestimmung der natürlichen Radionuklide 210Pb, 210Po, 226Ra, 228Ra, 234U und 238U in Trinkwasser

    Schuster, Martina

    2015-01-01

    Der Richtwert der effektiven Dosis für den Verzehr von Trinkwasser beträgt 0,1 mSv pro Jahr. Zur Berechnung der Dosis müssen die Aktivitätskonzentrationen der relevanten Radionuklide bestimmt werden. Einige Analysenmethoden zur Bestimmung dieser natürlichen Radionuklide sind bekannt, jedoch benötigt man für jedes Nuklid einen komplett anderen und zeitaufwändigen Trennungsgang. In dieser Arbeit wird eine Analysenmethode vorgestellt, mit der die natürlichen Radionuklide 210Pb, 210Po, 226Ra, 228...

  14. Accumulation of polonium 210Po, uranium (234U and 238U and plutonium (238Pu and 239+240Pu in tissues and organs of deer Carvidae from northern Poland

    Strumińska-Parulska D. I.

    2013-04-01

    Full Text Available Livers, kidneys and muscles of large herbivorous animals: roe deer (Capreolus capreolus, red deer (Cervus elaphus and fallow deer (Dama dama, collected in northern Poland, were the subject of the investigation. Polonium, uranium and plutonium activities were measured using alpha spectrometry along with relevant radiochemical procedures. The average concentrations of 210Po ranged between 0.02±0.01 Bq kg−1 ww in muscles and 7.15±0.12 Bq kg−1 ww in kidneys. The concentration of 238U ranged widely between 2.49±0.18 and 69.37±5.45 mBq kg−1 ww. The average concentrations of 239+240Pu ranged between 0.18±0.04 mBq kg−1 ww in muscle and 2.77±0.60 mBq kg−1 ww in kidneys. Statistical analysis showed that the sampling location, sex, age and species did not influence on the radioisotope activities in the analyzed samples.

  15. “The Woman Warrior versus The Chinaman Pacific: Must a Chinese American Critic Choose between Feminism and Heroism?” Conflicts in Feminism. Ed. Marianne Hirsch and Evelyn Fox Keller. New York: Routledge, 1990. 234-251

    Cheung, KK

    1991-01-01

    The chapter examines the tension between white feminism and ethnic feminism as well as between men and women in Asian American literary circles. Specifically it addresses Frank Chin’s attack on Maxine Hong Kingston over her depiction of Chinese sexism in The Woman Warrior and my own position as a literary critic torn between cultural nationalism and feminism. Using the opening of Kingston’s “China Men” as my point of departure, I urge Asian American men who feel “emasculated” by white culture...

  16. War and Peace in Qajar Persia. Implications Past andPresent. Londres et New York, Routledge, 2008, XI+234 p., cartes, photos, index. (History and Society in the Islamic World)

    Calmard, Jean

    2013-01-01

    Cet ouvrage collectif constitue l’édition d’une conférence tenue à Cambridge en juillet 2005. Dans son introduction, Mme Farmanfarmaian met l’accent sur l’impulsion donnée aux études qâjâres par l’établissement de l’International Qajar Association (IQSA) en 2000 qui nous a valu, notamment, « a plethora of new publications » (de valeurs très inégales à notre avis). Dans sa présentation des contributions de ce recueil, elle insiste sur le fait que les théories politiques, économiques et sociale...

  17. Multibeam collection for TN234: Multibeam data collected aboard Thomas G. Thompson from 2009-05-05 to 2009-05-10, departing from Apia, Western Samoa and returning to Apia, Western Samoa

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set is part of a larger set of data called the Multibeam Bathymetry Database (MBBDB) where other similar data can be found at...

  18. Optical and scintillation properties of Ce.sup.3+./sup.-doped YGd.sub.2./sub.Al.sub.5-x./sub.Ga.sub.x./sub.O.sub.12./sub. (x=2,3,4) single crystal scintillators

    Chewpraditkul, Wa.; Brůža, P.; Pánek, D.; Pattanaboonmee, N.; Wantong, K.; Chewpraditkul, W.; Babin, Vladimir; Bartosiewicz, Karol; Kamada, K.; Yoshikawa, A.; Nikl, Martin

    2016-01-01

    Roč. 169, Jan (2016), s. 43-50. ISSN 0022-2313 R&D Projects: GA ČR GAP204/12/0805; GA MŠk(CZ) LH14266 EU Projects: European Commission(XE) 316906 - LUMINET Institutional support: RVO:68378271 Keywords : YGd 2 Al 5-x Ga x O 12 :Ce * light yield * luminescence * scintillation Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.719, year: 2014

  19. Decree 234/003. Is derogate decree 317/987, from the date of entry into force the safe exercise regulation of the packing activities and the distribution of liquefied petroleum gas (LPG) that will dictate the URSEA

    This decree allows the entry into force the safe exercise regulation of the packing activities and the distribution of liquefied petroleum gas (LPG) that will dictate the URSEA (The regulatory unit of energy and water service)

  20. Procedures for determination of 239,240Pu, 241Am, 237Np, 234,238U, 228,230,232Th, 99Tc and 210Pb-210Po in environmental material

    Since 1987, the Department of Nuclear Safety Research, Risoe National Laboratory has developed procedures for analysis of low-level amounts of radioactivity in large samples of 200 liters seawater, 10 gram sediment, soil and other environmental materials. These analytical procedures provide high chemical yields, good resolution and excellent decontamination factors for large environmental samples analysed by alpha spectrometry and mass spectrometry (ICPMS). The procedures have been checked through practical analysis work and are used in Norway, the Netherlands, Germany, Spain, France and Denmark. (au)

  1. Analysis on the Polymorphism in Exons 2,3,4 of the MICA Genes in Han Nationality Population from Anhui Province%皖籍汉族人群MICA等位基因多态性的分布

    苏虹; 王保龙; 张秀军; 郝加虎; 肖琴; 叶冬青

    2006-01-01

    目的了解皖籍汉族正常人群中MICA(major histocompatibility complex class Ⅰchain-related gene A)等位基因的分布,为进一步研究MICA关联疾病的发病机制奠定基础.方法采用聚合酶链反应-序列特异性寡核苷酸探针杂交(polymerase chain reaction and sequence-specific oligonucleotide probing,PCR-SSOP)技术对112例正常人群进行MICA基因外显子2、3、4的多态性分析. 结果本研究人群的MICA基因多态性以MICA*008等位基因频率最高,达30.36%,其次为*010(16.96%)、*002(13.84%)和*009(12.05%).单倍型分析显示,MICA基因与多个HLA-B位点间存在连锁不平衡现象,有统计学意义的有MICA*008-B40、B07、B13,MICA*010-B46、B15,MICA*002-B35、B15和MICA*009-B52. 结论皖籍汉族正常人群的MICA等位基因分布具有其基本特点,MICA基因与HLA-B位点间存在广泛连锁不平衡.

  2. A Porcine Circovirus Type 2 (PCV2) Mutant with 234 Amino Acids in Capsid Protein Showed More Virulence In Vivo, Compared with Classical PCV2a/b Strain

    Guo, Longjun; Fu, Yujie; Wang, Yiping; Lu, Yuehua; Wei, Yanwu; Tang, Qinghai; Fan, Peihu; Liu, Jianbo; Zhang, Long; Zhang, Feiyan; Huang, Liping; Liu, Dan; Li, Shengbin; Wu, Hongli; Liu, Changming

    2012-01-01

    Background Porcine circovirus type 2 (PCV2) is considered to be the primary causative agent of postweaning multisystemic wasting syndrome (PMWS), which has become a serious economic problem for the swine industry worldwide. The major genotypes, PCV2a and PCV2b, are highly prevalent in the pig population and are present worldwide. However, another newly emerging PCV2b genotype mutant, which has a mutation in its ORF2-encoded capsid protein, has been sporadically present in China, as well as in...

  3. A porcine circovirus type 2 (PCV2 mutant with 234 amino acids in capsid protein showed more virulence in vivo, compared with classical PCV2a/b strain.

    Longjun Guo

    Full Text Available BACKGROUND: Porcine circovirus type 2 (PCV2 is considered to be the primary causative agent of postweaning multisystemic wasting syndrome (PMWS, which has become a serious economic problem for the swine industry worldwide. The major genotypes, PCV2a and PCV2b, are highly prevalent in the pig population and are present worldwide. However, another newly emerging PCV2b genotype mutant, which has a mutation in its ORF2-encoded capsid protein, has been sporadically present in China, as well as in other countries. It is therefore important to determine the relative virulence of the newly emerging PCV2b genotype mutant, compared with the existing PCV2a and PCV2b genotypes, and to investigate whether the newly emerging mutant virus induces more severe illness. METHODOLOGY/PRINCIPAL FINDINGS: Twenty healthy, 30-day-old, commercial piglets served as controls or were challenged with PCV2a, PCV2b and the newly emerging mutant virus. A series of indexes representing different parameters were adopted to evaluate virulence, including clinical signs, serological detection, viral load and distribution, changes in immune cell subsets in the peripheral blood, and evaluation of pathological lesions. The newly emerging PCV2 mutant demonstrated more severe signs compatible with PMWS, characterized by wasting, coughing, dyspnea, diarrhea, rough hair-coat and depression. Moreover, the pathological lesions and viremia, as well as the viral loads in lymph nodes, tonsils and spleen, were significantly more severe (P<0.05 for piglets challenged with the newly emerging mutant compared with those in the groups challenged with PCV2a and PCV2b. In addition, a significantly lower average daily weight gain (P<0.05 was recorded in the group challenged with the newly emerging PCV2 mutant than in the groups challenged with the prevailing PCV2a and PCV2b. CONCLUSIONS: This is believed to be the first report to confirm the enhanced virulence of the newly emerging PCV2 mutant in vivo.

  4. Measurements of the Electric Form Factor of the Neutron up to Q2=3.4 GeV2 using the Reaction He3(e,e'n)pp

    Riordan, S; Craver, B; Kelleher, A; Kolarkar, A; Miller, J; Cates, G D; Liyanage, N; Wojtsekhowski, B; Acha, A; Allada, K; Anderson, B; Aniol, K A; Annand, J R M; Arrington, J; Averett, T; Beck, A; Bellis, M; Boeglin, W; Breuer, H; Calarco, J R; Camsonne, A; Chen, J P; Chudakov, E; Coman, L; Crowe, B; Cusanno, F; Day, D; Degtyarenko, P; Dolph, P A M; Dutta, C; Ferdi, C; Fernandez-Ramirez, C; Feuerbach, R; Fraile, L M; Franklin, G; Frullani, S; Fuchs, S; Garibaldi, F; Gevorgyan, N; Gilman, R; Glamazdin, A; Gomez, J; Grimm, K; Hansen, J O; Herraiz, J L; Higinbotham, D W; Holmes, R; Holmstrom, T; Howell, D; deJager, C W; Jiang, X; Jones, M K; Katich, J; Kaufman, L J; Khandaker, M; Kelly, J J; Kiselev, D; Korsch, W; LeRose, J; Lindgren, R; Markowitz, P; Margaziotis, D J; Beck, S May-Tal; Mayilyan, S; McCormick, K; Meziani, Z E; Michaels, R; Moffit, B; Nanda, S; Nelyubin, V; Ngo, T; Nikolenko, D M; Norum, B; Pentchev, L; Perdrisat, C F; Piasetzky, E; Pomatsalyuk, R; Protopopescu, D; Puckett, A J R; Punjabi, V A; Qian, X; Qiang, Y; Quinn, B; Rachek, I; Ransome, R D; Reimer, P E; Reitz, B; Roche, J; Ron, G; Rondon, O; Rosner, G; Saha, A; Sargsian, M; Sawatzky, B; Segal, J; Shabestari, M; Shahinyan, A; Shestakov, Yu; Singh, J; Sirca, S; Souder, P; Stepanyan, S; Stibunov, V; Sulkosky, V; Tajima, S; Tobias, W A; Udias, J M; Urciuoli, G M; Vlahovic, B; Voskanyan, H; Wang, K; Wesselmann, F R; Vignote, J R; Wood, S A; Wright, J; Yao, H; Zhu, X

    2010-01-01

    The electric form factor of the neutron was determined from studies of the reaction He3(e,e'n)pp in quasi-elastic kinematics in Hall A at Jefferson Lab. Longitudinally polarized electrons were scattered off a polarized target in which the nuclear polarization was oriented perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons that were registered in a large-solid-angle detector. More than doubling the Q2-range over which it is known, we find GEn = 0.0225 +/- 0.0017 (stat) +/- 0.0024 (syst), 0.0200 +/- 0.0023 +/- 0.0018, and 0.0142 +/- 0.0019 +/- 0.0013 for Q2 = 1.72, 2.48, and 3.41 GeV2, respectively.

  5. Measurements of the electric form factor of the neutron up to Q2=3.4 GeV2 using the reaction 3He(e,e'n)pp.

    Riordan, S; Abrahamyan, S; Craver, B; Kelleher, A; Kolarkar, A; Miller, J; Cates, G D; Liyanage, N; Wojtsekhowski, B; Acha, A; Allada, K; Anderson, B; Aniol, K A; Annand, J R M; Arrington, J; Averett, T; Beck, A; Bellis, M; Boeglin, W; Breuer, H; Calarco, J R; Camsonne, A; Chen, J P; Chudakov, E; Coman, L; Crowe, B; Cusanno, F; Day, D; Degtyarenko, P; Dolph, P A M; Dutta, C; Ferdi, C; Fernández-Ramírez, C; Feuerbach, R; Fraile, L M; Franklin, G; Frullani, S; Fuchs, S; Garibaldi, F; Gevorgyan, N; Gilman, R; Glamazdin, A; Gomez, J; Grimm, K; Hansen, J-O; Herraiz, J L; Higinbotham, D W; Holmes, R; Holmstrom, T; Howell, D; de Jager, C W; Jiang, X; Jones, M K; Katich, J; Kaufman, L J; Khandaker, M; Kelly, J J; Kiselev, D; Korsch, W; LeRose, J; Lindgren, R; Markowitz, P; Margaziotis, D J; Beck, S May-Tal; Mayilyan, S; McCormick, K; Meziani, Z-E; Michaels, R; Moffit, B; Nanda, S; Nelyubin, V; Ngo, T; Nikolenko, D M; Norum, B; Pentchev, L; Perdrisat, C F; Piasetzky, E; Pomatsalyuk, R; Protopopescu, D; Puckett, A J R; Punjabi, V A; Qian, X; Qiang, Y; Quinn, B; Rachek, I; Ransome, R D; Reimer, P E; Reitz, B; Roche, J; Ron, G; Rondon, O; Rosner, G; Saha, A; Sargsian, M M; Sawatzky, B; Segal, J; Shabestari, M; Shahinyan, A; Shestakov, Yu; Singh, J; Sirca, S; Souder, P; Stepanyan, S; Stibunov, V; Sulkosky, V; Tajima, S; Tobias, W A; Udias, J M; Urciuoli, G M; Vlahovic, B; Voskanyan, H; Wang, K; Wesselmann, F R; Vignote, J R; Wood, S A; Wright, J; Yao, H; Zhu, X

    2010-12-31

    The electric form factor of the neutron was determined from studies of the reaction 3He(e,e'n)pp in quasielastic kinematics in Hall A at Jefferson Lab. Longitudinally polarized electrons were scattered off a polarized target in which the nuclear polarization was oriented perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons that were registered in a large-solid-angle detector. More than doubling the Q2 range over which it is known, we find G(E)(n)=0.0236±0.0017(stat)±0.0026(syst), 0.0208±0.0024±0.0019, and 0.0147±0.0020±0.0014 for Q(2)=1.72, 2.48, and 3.41 GeV2, respectively. PMID:21231649

  6. Effect of CuO2 planes on the structural and superconducting transport properties of [CuTl ‑ 12(n ‑ 1)n;n = 2,3,4] superconductor family

    Muzaffar, M. Usman; Khan, Nawazish A.

    2016-06-01

    Cu0.5Tl0.5Ba2Can‑1CunO2n+4‑δ (n = 2, 3, 4) superconducting bulk samples have been synthesized by using two-step solid state reaction method. We investigated the effects of CuO2 planes on the structural and superconducting transport properties of [CuTl ‑ 12(n ‑ 1)n; n = 2, 3, 4] superconducting family. These samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) absorption spectroscopy and DC-resistivity (ρ) measurements. These samples are c-axis length oriented and have shown orthorhombic crystal structure. All the samples have shown metallic variations of resistivity from room temperature down to onset of superconductivity. The zero resistivity critical temperature Tc(R = 0) increases with the increase in superconducting planes and normal state resistivity systematically decreases, which show the density of inadvertent defects decreases in the final compound. The apical oxygen phonon modes are hardened as observed in the FTIR absorption measurements. The intrinsic microscopic superconducting parameters, such as the cross-over temperatures, coherence length along c-axis (ξc(0)) at 0 K, inter-layer coupling (J), inter-grain coupling (α) and fermi velocity (VF), were extracted from the fluctuation-induced conductivity (FIC) analysis. FIC analysis also showed the improvement in superconductivity with the increase in CuO2 planes.

  7. Anti-inflammatory effect of 3,4-DHPEA-EDA [2-(3,4 -hydroxyphenyl) ethyl (3S, 4E)-4-formyl-3-(2-oxoethyl)hex-4-enoate] on primary human vascular endothelial cells.

    Sindona, G; Caruso, A; Cozza, A; Fiorentini, S; Lorusso, B; Marini, E; Nardi, M; Procopio, A; Zicari, S

    2012-01-01

    Diets in which fat is significantly provided by olive oil and are relatively rich in vegetables, have been associated with a low incidence of cardiovascular diseases, mostly due to the presence of several phenolic compounds which have anti-oxidant and antiinflammatory properties. [1]. In this work, we describe the anti-inflammatory effect of 3,4-DHPEA-EDA in a cell model that we developed to mimic inflammatory injury of endothelium. This was based on the production of the proinflammatory chemokine CCL2, following in vitro stimulation of primary human endothelial cells. Pre-treatment of cells with 3,4-DHPEA-EDA resulted in a dose-dependent inhibition of CCL2 secretion. The effect of 3,4-DHPEA-EDA on CCL2 expression was observed at the transcriptional level. Functional data have shown that 3,4-DHPEA-EDA diminished monocyte adhesion to HUVECs. These results point on the use of 3,4- DHPEA-EDA as a novel drug aimed to prevent or reduce inflammation of endothelium. PMID:22680639

  8. Sorption studies of radioelements on geological materials

    Batch sorption experiments have been carried out to study the sorption of uranium, technetium, curium, neptunium, actinium, protactinium, polonium, americium and plutonium onto bentonite, granodiorite and tuff. Mathematical modelling using the HARPHRQ program and the HATCHES database was carried out to predict the speciation of uranium and technetium in the equilibrated seawater, and neptunium, americium and plutonium in the rock equilibrated water. Review of the literature for thermodynamic data for curium, actinium, protactinium and polonium was carried out. Where sufficient data were available, predictions of the speciation and solubility were made. This report is a summary report of the experimental work conducted by AEA Technology during April 1991-March 1998, and the main results have been presented at Material Research Society Symposium Proceedings and published as proceedings of them. (author)

  9. Investigation for determining the retention properties of rock over the ASSE II mine for dissolved radionuclides

    For a model consideration of groundwater movement and the associated transport of dissolved substance in deep groundwater, the retention properties of the ASSE II mine for radionuclides dissolved in water were determined. A series of properties of rocks were examined and described for this purpose. Apart from the chemical, mineralogical and petrophysical characteristics of the rocks, the retention was determined by 3 different methods and stated in the form of distribution coefficients for specific elements. A comparison of the results of vibration and diffusion experiments gave good agreement, while the results in through column experiments only reached the same order of magnitude after an expensive determination with the aid of a place concentration distribution. The distribution coefficients for the elements carbon, selenium, strontium, technetium, iodine, caesium, lead, radium, actinium, proto-actinium, uranium, neptunium, plutonium, americium and curium are listed and collected for model rock packages. (orig./HP)

  10. Sorption studies of radioelements on geological materials

    Berry, J. A; 油井 三和; 北村 暁

    2007-01-01

    Batch sorption experiments have been carried out to study the sorption of uranium, technetium, curium, neptunium, actinium, protactinium, polonium, americium and plutonium onto bentonite, granodiorite and tuff. Mathematical modelling using the HARPHRQ program and the HATCHES database was carried out to predict the speciation of uranium and technetium in the equilibrated seawater, and neptunium, americium and plutonium in the rock equilibrated water. Review of the literature for thermodynamic ...

  11. Purification of cerium, neodymium and gadolinium for low background experiments

    Boiko R.S.; Barabash A.S.; Belli P.; Bernabei R.; Cappella F.; Cerulli R.; Danevich F.A.; Incicchitti A.; Laubenstein M.; Mokina V.M.; Nisi S.; Poda D.V.; Polischuk O.G.; Tretyak V.I.

    2014-01-01

    Cerium, neodymium and gadolinium contain double beta active isotopes. The most interesting are 150Nd and 160Gd (promising for 0ν2β search), 136Ce (2β+ candidate with one of the highest Q2β). The main problem of compounds containing lanthanide elements is their high radioactive contamination by uranium, radium, actinium and thorium. The new generation 2β experiments require development of methods for a deep purification of lanthanides from the radioactive elements. A combination of physical an...

  12. LASL experience in decontamination of the environment

    This discussion represents one part of a major effort in soil decontamination at the Los Alamos site. A contaminated industrial waste line in the Los Alamos townsite was removed, and a plutonium incineration facility, and a filter building contaminated with actinium-227 were dismantled. The former plutonium handling facility has been decontaminated, and canyons and an old firing site contaminated with strontium-90 have been surveyed

  13. Study of the origin of elements of the uranium-235 family observed in excess in the vicinity of the experimental nuclear EL4 reactor under dismantling. Lessons got at this day and conclusions; Etude de l'origine des elements de la famille de l'uranium-235 observes en exces dans les environs du reacteur nucleaire experimental EL4 en cours de demantelement. Enseignements retires a ce jour et conclusion

    NONE

    2007-07-01

    This study resumes the discovery of an excess of actinium 227 found around by EL4 nuclear reactor actually in dismantling. The search for the origin of this excess revealed a real inquiry of investigation during three years. Because a nuclear reactor existed in this area a particular attention will have concerned this region. The doubt became the line of conduct to find the answer to the human or natural origin of this excess. Finally and against any evidence, it appears that the origin of this phenomenon was natural, consequence of the particular local geology. The detail of the different investigations is given: search of a possible correlation with the composition of elevations constituent of lanes, search (and underlining) of new sites in the surroundings of the Rusquec pond and the Plouenez station, study of the atmospheric deposits under winds of the nuclear power plant and in the east direction, search of a possible relationship with the gaseous effluents of the nuclear power plant in the past, historical study of radioactive effluents releases in the fifty last years by the analysis of the sedimentary deposits in the Saint-Herbiot reservoir, search of a possible correlation between the excess of actinium 227 and the nuclear power plant activity; search of a possible correlation with a human activity without any relationship with the nuclear activities, search of a correlation with the underground waters, search of a correlation with the geological context, collect of information on the possible transfers in direction of the food chain, determination of the radiological composition of the underground waters ( not perturbed by human activity), search of the cause of an excess of actinium 227 in the old channel of liquid effluents release of the nuclear power plant. The results are given and discussed. And contrary to all expectations the origin of the excess of actinium 227 is completely natural. (N.C.)

  14. The discoveries of uranium 237 and symmetric fission — From the archival papers of Nishina and Kimura

    IKEDA, Nagao

    2011-01-01

    Shortly before the Second World War time, Nishina reported on a series of prominent nuclear physical and radiochemical studies in collaboration with Kimura. They artificially produced 231Th, a member of the natural actinium series of nuclides, by bombarding thorium with fast neutrons. This resulted in the discovery of 237U, a new isotope of uranium, by bombarding uranium with fast neutrons, and confirmed that 237U disintegrates into element 93 with a mass number of 237. They also identified t...

  15. History of the unraveling of the natural decay series

    Milestones in the subject of radioactivity, which were important to the unraveling of natural decay series, have been identified and described. The interplay between all these issues is very complex, and some aspects of the development of the uranium series is discussed as an example, the thorium and actinium series evolved in a similar way from research by many of the same people. All three series as understood in 1913 are compared with their present-day representation. (orig.)

  16. History of the unraveling of the natural decay series

    Milestones in the subject of radioactivity, which were important to the unraveling of natural decay series, have been identified and described. The interplay between all these issues is very complex, and some aspects of the development of the uranium series is discussed as an example, the thorium and actinium series evolved in a similar way from research by many of the same people. All three series as understood in 1913 are compared with their present-day representation. (author)

  17. Dicty_cDB: [Dicty_cDB

    Full Text Available VF (Link to library) VFC234 (Link to dictyBase) - - - Contig-U16464-1 VFC234P (Link... to Original site) VFC234F 292 VFC234Z 462 VFC234P 754 - - Show VFC234 Library VF (Link to library) Clone ID VFC234 (Link to dict...yBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig Contig-U16464-1 Original site URL http://dict...2 5e-06 6 AL844509 |AL844509.1 Plasmodium falciparum chromosome 13. 48 4e-04 4 AC117075 |AC117075.2 Dict...brane 4.0 %: Golgi 4.0 %: vesicles of secretory system >> prediction for VFC234 is nuc 5' end seq. ID VFC234

  18. System for recovery of daughter isotopes from a source material

    Tranter, Troy J [Idaho Falls, ID; Todd, Terry A [Aberdeen, ID; Lewis, Leroy C [Idaho Falls, ID; Henscheid, Joseph P [Idaho Falls, ID

    2009-08-04

    A method of separating isotopes from a mixture containing at least two isotopes in a solution is disclosed. A first isotope is precipitated and is collected from the solution. A daughter isotope is generated and collected from the first isotope. The invention includes a method of producing an actinium-225/bismuth-213 product from a material containing thorium-229 and thorium-232. A solution is formed containing nitric acid and the material containing thorium-229 and thorium-232, and iodate is added to form a thorium iodate precipitate. A supernatant is separated from the thorium iodate precipitate and a second volume of nitric acid is added to the thorium iodate precipitate. The thorium iodate precipitate is stored and a decay product comprising actinium-225 and bismuth-213 is generated in the second volume of nitric acid, which is then separated from the thorium iodate precipitate, filtered, and treated using at least one chromatographic procedure. A system for producing an actinium-225/bismuth-213 product is also disclosed.

  19. Behaviour of uranium series radionuclides in surface water (Crouzille, Limousin). Geochemical implications

    Understanding natural radionuclides behaviour in surface water is a required step to achieve uranium mine rehabilitation and preserve water quality. The first objective of this thesis is to determine which are the radionuclides sources in a drinking water reservoir. The second objective is to improve the knowledge about the behaviour of uranium series radionuclides, especially actinium. The investigated site is a brook (Sagnes, Limousin, France) which floods a peat bog contaminated by a former uranium mine and which empties into the Crouzille lake. It allows studying radionuclides transport in surface water and radionuclides retention through organic substance or water reservoir. Radionuclides distribution in particulate, colloidal and dissolved phases is determined thanks to ultra-filtrations. Gamma spectrometry allows measuring almost all natural radionuclides with only two counting stages. However, low activities of 235U series radionuclides impose the use of very low background well-type Ge detectors, such as those of the Underground Laboratory of Modane (France). Firstly, this study shows that no or few radionuclides are released by the Sagnes peat bog, although its radioactivity is important. Secondly, it provides details on the behaviour of uranium series radionuclides in surface water. More specifically, it provides the first indications of actinium solubility in surface water. Actinium's behaviour is very close to uranium's even if it is a little less soluble. (author)

  20. Efficiency defense and administrative fuzziness in merger regulation

    Medvedev, Andrei

    -, č. 234 (2004), s. 1-42. ISSN 1211-3298 Institutional research plan: CEZ:AV0Z7085904 Keywords : merger regulation * efficiency defense Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/wp/Wp234.pdf

  1. Extraction of selected compounds of mercury from the real samples for speciation analysis using RP-HPLC-UV-CVG-QTAAS

    Kolorosová, A.; Linhart, O.; Červený, V.; Kratzer, Jan; Hraníček, J.; Rychlovský, P.

    2015. s. 234-234. [Colloquium Spectroscopicum Internationale /39./. 30.08.2015-03.09.2015, Figueira da Foz] Institutional support: RVO:68081715 Keywords : mercury * speciation analysis * UV generation Subject RIV: CB - Analytical Chemistry, Separation

  2. Pediatric Palliative Care: A Personal Story

    Full Text Available ... total__ Find out why Close Pediatric Palliative Care: A Personal Story NINRnews Subscribe Subscribed Unsubscribe 234 234 ... later? Sign in to add this video to a playlist. Sign in Share More Report Need to ...

  3. EST Table: FS829498 [KAIKOcDNA[Archive

    Full Text Available FS829498 E_FL_fmgV_32C07_R_0 10/09/28 34 %/210 aa ref|XP_001656347.1| bestrophin 2,...3,4 [Aedes aegypti] gb|EAT45610.1| bestrophin 2,3,4 [Aedes aegypti] 10/09/10 32 %/234 aa FBpp0113082|Best1-P

  4. 49 CFR 212.231 - Highway-rail grade crossing inspector.

    2010-10-01

    ... Grade Crossing Signal System Safety Rules (49 CFR part 234); (3) Knowledge of operating practices and... the Grade Crossing Signal System Safety Rules (49 CFR part 234), including the remedial action... determining compliance with Grade Crossing Signal System Safety Rules (49 CFR part 234), to make reports...

  5. Comment on Spracklandus Hoser, 2009 (Reptilia, Serpentes, ELAPIDAE): request for confirmation of availability of the generic name and for the nomenclatural validation of the journal in which it was published (Case 3601; BZN 70:234–237; 71:30–38; 133-135,181-182 ,252-253)

    Rhodin, Anders G.J.; Kaiser, Hinrich; van Dijk, Peter Paul; Wüster, Wolfgang; O’Shea, Mark; Archer, Michael; Auliya, Mark; Boitani, Luigi; Bour, Roger; Clausnitzer, Viola; Contreras-MacBeath, Topiltzin; Crother, Brian I.; Daza, Juan M.; Driscoll, Carlos A.; Flores-Villela, Oscar; Frazier, Jack; Fritz, Uwe; Gardner, Alfred L.; Gascon, Claude; Georges, Arthur; Glaw, Frank; Grazziotin, Felipe G.; Groves, Colin P.; Haszprunar, Gerhard; Havaš, Peter; Hero, Jean-Marc; Hoffmann, Michael; Hoogmoed, Marinus S.; Horne, Brian D.; Iverson, John B.; Jäch, Manfred; Jenkins, Christopher L.; Jenkins, Richard K.B.; Kiester, A. Ross; Keogh, J. Scott; Lacher, Thomas E., Jr.; Lovich, Jeffrey E.; Luiselli, Luca; Mahler, D. Luke; Mallon, David P.; Mast, Roderic; McDiarmid, Roy W.; Measey, John; Mittermeier, Russell A.; Molur, Sanjay; Mosbrugger, Volker; Murphy, Robert W.; Naish, Darren; Niekisch, Manfred; Ota, Hidetoshi; Parham, James F.; Parr, Michael J.; Pilcher, Nicolas J.; Pine, Ronald H.; Rylands, Anthony B.; Sanderson, James G.; Savage, Jay M.; Schleip, Wulf; Scrocchi, Gustavo J.; Shaffer, H. Bradley; Smith, Eric N.; Sprackland, Robert; Stuart, Simon N.; Vetter, Holger; Vitt, Laurie J.; Waller, Tomás; Webb, Grahame; Wilson, Edward O.; Zaher, Hussam; Thomson, Scott

    2015-01-01

    In Case 3601 Raymond Hoser has asked the Commission to validate for the purposes of nomenclature the name Spracklandus Hoser, 2009, and ‘the journal in which it was published,’ issue 7 of the Australasian Journal of Herpetology (AJH). We note that the entire run of AJH has been written, edited, and published solely by Hoser. Although his requests to the Commission were presented as narrow and, in his words, ‘routine matters,’ we are convinced that they represent an important tipping-point with broad implications of major concern for zoological taxonomy and nomenclature as a whole and, by extension, the greater scientific community. Since Hoser’s actions and works have failed to follow scientific best practices (e.g. Turtle Taxonomy Working Group, 2007, 2014; Kaiser et al., 2013; Kaiser, 2014) and both the Commission’s general Recommendations and Code of Ethics in Appendix A, the global herpetological community has widely rejected his taxonomic decisions and resultant nomenclature. This has unfortunately caused a confusing dual nomenclature to develop in the herpetological community, with most boycotting or ignoring Hoser’s 700+ new names coined in the AJH, while he and a few personal followers actively promote their usage. We believe that suppression of the name Spracklandus, and all issues of AJH, is the only effective way to bring this contentious and confusing issue to resolution. The plenary power available under Article 81.1 of the Code exist specifically to allow the Commission to make rulings in individual cases that disturb stability and cause confusion, whether the works are Code-compliant or not. We maintain that it is in the interest of nomenclatural stability, not only for herpetology, but for all of zoological taxonomy, that the plenary power be invoked to declare the works in AJH unavailable, regardless of any narrow interpretation of their technical Code-compliance. We present our arguments for rejection of the validity of AJH in the following commentary. In view of the wide-reaching implications of this case for all of zoology, and reflecting the deep and broad-based community concern over these issues, our contributing authors include 70 global scientific leaders and accomplished amateurs from a wide variety of zoological disciplines.

  6. 兔TLR2、TLR3和TLR4部分cDNA序列的克隆及分析%Cloning and sequence analysis of cDNA encoding rabbit Toll-like receptor2,3,4

    聂奎; 曾兴艳; 周作勇; 王裕文

    2012-01-01

    In this study, Toll-like receptor 2 (R TLR2 ), Toll-like receptor-3 (R TLR3) and Toll-like receptor-4 (R TLR4 ) gene were cloned from Japanese white rabbits spleen by reverse transcription-polymerase chain reaetion(RT-PCR). Sequence analysis indicated that the RTLR2,RTLR3 and RTLR4 eDNA cloned were 128,150 and 139 bp in length and that the nucleotide sequence of RTLR2 shared 99 % homology with the published sequence Oryctolagus cuniculus TLR2(NM_001082781),while RTLR3 and RTLR4 shared 100% homology with the published sequence TLR3 (NM_001082219)and TLR4 (NM_001082732). The predicted amino acid sequence of RTLR2,RTLR3 and RTLR4 gene was compared to that of the partial cDNA fragments of Oryctolagus cuniculus TLR2, TLR3 and TLR4, with 100% similarity. The comparison of the deduced amino acids sequence of R TLR2,RTLR3 and R TLR4 with that of horse,dog,cat, orangutan,human, cattle sheep and mouse showed that the amino acids homology similarity were 80%,78%,78%,78%,78%,76%,73% and 61% in TLR2,97%,97%,95%,95%,95%,95%,93%and 93% in TLR3, and 75 %, 75 %, 75 %, 73 %,71 %, 66 %,66 % and 62 % in TLR4, respectively. Based on the phylogenetic tree and alignment of predicted animo sequence,we concluded that R TLR2,RTLR3 and RTLR4 were partial eDNA fragments of Oryctolagus cuniculus TLR2,TLR3 and TLR4,individually. Likewise,it was suggested that there was species-specific of TLRs in different kinds of animials.%用RT-PCR技术从日本大耳白兔脾脏组织克隆出兔Toll样受体2、3、4基因(拟命名为RTLR2、R TLR3和RTLR4)的cDNA序列并进行测序,获得的3个Toll样受体基因序列长分别为128、150和139bp,并将其测序结果与GenBank中登录的穴兔(Oryctolagus cuniculus)的Toils核苷酸序列进行比对,发现本次克隆到的RTLR2与穴兔TLR2的基因序列(NM_001082781)相似性为99%,而RTLR3与TLR3(NM_001082219)和RTLR4与TLR4(NM_001082732)相似性均为100%。Protein Blast同源性结果显示,RTLR2、RTLR3和RTLR4的氨基酸序列与穴兔TLR2、TLR3和TLR4的同源性皆为100%,与马、人、野猪等其他8种动物TLRs的比较,与RTLR2同源性最高的是马的80%,其他的只有61%~78%;与RTLR3同源性最高是马和野猪的97%,其他也较高达93%~95%;而RTLR4与其他8种动物的同源性均较低75%以下。结果表明:RTLR2、RTLR3和RTLR4分别为免TLR2、TLR3和TLR4的部分cDNA基因序列;TLRs在不同物种的进化过程中存在种属特异性。

  7. Comment on "Radiocarbon Calibration Curve Spanning 0 to 50,000 Years B.P. Based on Paired 230Th/234U/238U and 14C Dates on Pristine Corals" by R.G. Fairbanks, R. A. Mortlock, T.-C. Chiu, L. Cao, A. Kaplan, T. P. Guilderson, T. W. Fairbanks, A. L. Bloom, P

    Reimer, P J; Baillie, M L; Bard, E; Beck, J W; Blackwell, P G; Buck, C E; Burr, G S; Edwards, R L; Friedrich, M; Guilderson, T P; Hogg, A G; Hughen, K A; Kromer, B; McCormac, G; Manning, S; Reimer, R W; Southon, J R; Stuiver, M; der Plicht, J v; Weyhenmeyer, C E

    2005-10-02

    Radiocarbon calibration curves are essential for converting radiocarbon dated chronologies to the calendar timescale. Prior to the 1980's numerous differently derived calibration curves based on radiocarbon ages of known age material were in use, resulting in ''apples and oranges'' comparisons between various records (Klein et al., 1982), further complicated by until then unappreciated inter-laboratory variations (International Study Group, 1982). The solution was to produce an internationally-agreed calibration curve based on carefully screened data with updates at 4-6 year intervals (Klein et al., 1982; Stuiver and Reimer, 1986; Stuiver and Reimer, 1993; Stuiver et al., 1998). The IntCal working group has continued this tradition with the active participation of researchers who produced the records that were considered for incorporation into the current, internationally-ratified calibration curves, IntCal04, SHCal04, and Marine04, for Northern Hemisphere terrestrial, Southern Hemisphere terrestrial, and marine samples, respectively (Reimer et al., 2004; Hughen et al., 2004; McCormac et al., 2004). Fairbanks et al. (2005), accompanied by a more technical paper, Chiu et al. (2005), and an introductory comment, Adkins (2005), recently published a ''calibration curve spanning 0-50,000 years''. Fairbanks et al. (2005) and Chiu et al. (2005) have made a significant contribution to the database on which the IntCal04 and Marine04 calibration curves are based. These authors have now taken the further step to derive their own radiocarbon calibration extending to 50,000 cal BP, which they claim is superior to that generated by the IntCal working group. In their papers, these authors are strongly critical of the IntCal calibration efforts for what they claim to be inadequate screening and sample pretreatment methods. While these criticisms may ultimately be helpful in identifying a better set of protocols, we feel that there are also several erroneous and misleading statements made by these authors which require a response by the IntCal working group. Furthermore, we would like to comment on the sample selection criteria, pretreatment methods, and statistical methods utilized by Fairbanks et al. in derivation of their own radiocarbon calibration.

  8. Francisco García González, Familia y sociedad en Zacatecas. La vida de un microcosmos minero novohispano, 1750-1830, México, El Colegio de México-Universidad Autónoma de Zacatecas, 2000, 234 pp.

    Langue, Frédérique

    2005-01-01

    Dentro de un nutrido panorama de investigaciones dedicadas a la ciudad y a su entorno desde las perspectivas y para los períodos más diversos, esta entrega se focaliza en un aspecto algo descuidado por la historiografía zacatecanista. Partiendo tanto del concepto de vida privada como de los métodos propios de la historia de la familia, el autor centra su aproximación en el "nuevo pasado familiar", y busca ofrecer un estudio sistemático de la familia en el lapso de tiempo considerado, en la lí...

  9. María Judith Ress, Sin visiones nos perdemos. Reflexiones sobre Teología Ecofeminista Latinoamericana (Traducción de Maruja González Torre), Edición de Colectivo Cons-pirando, Santiago, 2012, 234 p.

    Pozzoli, María Teresa

    2012-01-01

    Este comentario sobre el texto “Sin visiones nos perdemos” parte considerando la premisa del Pensamiento Complejo que refiere a que el ‘sujeto’ (la autora) y el ‘objeto’ (el texto) están inseparablemente unidos. En el método “implexo” que he desarrollado y aplico para realizar intervenciones educativas y comunitarias, las realidades particulares del sujeto y su biografía son herramientas que activan sus procesos de ampliación de la conciencia. En ese sentido, es necesario también centralizar ...

  10. Synthesis and Characterization of Mixed Chalcogen Triangular Complexes with New Mo-3(mu(3)-S)(mu(2)-Se-2)(3)(4+) and M-3(mu(3)-S)mu(2)-Se)(3)(4+) (M = Mo, W) Cluster Cores

    Gushchin, Artem; Ooi, Bee Lean; Harris, Pernille;

    2009-01-01

    In our pursuit of mixed chalcogen-bridged cluster complexes, solids of the compositions Mo3SSe6Br4 and W3SSe6Br4 were prepared using high-temperature synthesis from the elements. Treatment of Mo3SSe6Br4 with Bu4NBr in a vibration mill yielded (Bu4N)(3)([Mo-3(mu(3)-S)(mu(2)-Se-2)(3)Br-6]Br} (I). I...

  11. DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS

    P. Bernot

    2005-07-13

    The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this activity is to predict dissolved concentrations or solubility limits for elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) relevant to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are provided in the form of tabulated functions with pH and log fCO{sub 2} as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. Even though selection of an appropriate set of radionuclides documented in Radionuclide Screening (BSC 2002 [DIRS 160059]) includes actinium, transport of Ac is not modeled in the total system performance assessment for the license application (TSPA-LA) model because of its extremely short half-life. Actinium dose is calculated in the TSPA-LA by assuming secular equilibrium with {sup 231}Pa (Section 6.10); therefore, Ac is not analyzed in this report. The output data from this report are fundamental inputs for TSPA-LA used to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for the actinides discussed in this report. These models cover broad ranges of environmental conditions so they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or

  12. DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS

    The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this activity is to predict dissolved concentrations or solubility limits for elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) relevant to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are provided in the form of tabulated functions with pH and log fCO2 as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. Even though selection of an appropriate set of radionuclides documented in Radionuclide Screening (BSC 2002 [DIRS 160059]) includes actinium, transport of Ac is not modeled in the total system performance assessment for the license application (TSPA-LA) model because of its extremely short half-life. Actinium dose is calculated in the TSPA-LA by assuming secular equilibrium with 231Pa (Section 6.10); therefore, Ac is not analyzed in this report. The output data from this report are fundamental inputs for TSPA-LA used to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for the actinides discussed in this report. These models cover broad ranges of environmental conditions so they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or otherwise

  13. Detection of rare earth elements in Powder River Basin sub-bituminous coal ash using laser-induced breakdown spectroscopy (LIBS)

    Tran, Phuoc [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United State; Mcintyre, Dustin [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United State

    2015-10-01

    We reported our preliminary results on the use of laser-induced breakdown spectroscopy to analyze the rare earth elements contained in ash samples from Powder River Basin sub-bituminous coal (PRB-coal). We have identified many elements in the lanthanide series (cerium, europium, holmium, lanthanum, lutetium, praseodymium, promethium, samarium, terbium, ytterbium) and some elements in the actinide series (actinium, thorium, uranium, plutonium, berkelium, californium) in the ash samples. In addition, various metals were also seen to present in the ash samples

  14. An aerial radiological survey of the Sandia National Laboratories and surrounding area

    A team from the Remote Sensing Laboratory conducted an aerial radiological survey of the area surrounding the Sandia National Laboratories and Kirtland Air Force Base in Albuquerque, New Mexico, during March and April 1993. The survey team measured the terrestrial gamma radiation at the site to determine the levels of natural and man-made radiation. This survey includes the areas covered by a previous survey in 1981. The results of the aerial survey show a background exposure rate which varies between 5 and 18 μR/h plus an approximate 6 μR/h contribution from cosmic rays. The major radioactive isotopes found in this survey were: potassium-40, thallium-208, bismuth-214, and actinium-228, which are all naturally-occurring isotopes, and cobalt-60, cesium-137, and excess amounts of thallium-208 and actinium-228, which are due to human actions in the survey area. In regions away from man-made activity, the exposure rates inferred from this survey's gamma ray measurements agree almost exactly with the exposure rates inferred from the 1981 survey. In addition to the aerial measurements, another survey team conducted in situ and soil sample radiation measurements at three sites within the survey perimeter. These ground-based measurements agree with the aerial measurements within ± 5%

  15. Mixed valency of the RE and Ac ions in solid states

    Full text: This review is devoted to consideration of the methods and results of the theoretical and experimental investigations of the electronic state of the rare earths and actinium ions in the separate compound. The methods of the high resolution X ray spectroscopy were used for our consideration. Energy of the X ray lines of the rare earths and actinium ions in free state and solid states was study carefully. Valency shifts of X Ray lines under change of electronic state of nf - ions in different oxide, fluoride and chloride compounds were determined for K -, L- and M - lines for these ions with accuracy near 10 -100 MeV. We studied the electronic state of nf- ions which is changed from '+2' to '+4' and determined the concentration of ions in different electronic state. Relative error for theoretical energy of the most lines for HFP - approach in comparison with experiment is less than 0.5%, and deviation for concentration is less than 5%

  16. A study of uranium and thorium migration at the Koongarra uranium deposit with application to actinide transport from nuclear waste repositories

    One way to gain confidence in modelling possible radionuclide releases is to study natural systems which are similar to components of the multibarrier waste repository. Several such analogues are currently under study and these provide useful data about radionuclide behaviour in the natural environment. One such system is the Koongarra uranium deposit in the Northern Territory. In this dissertation, the migration of actinides, primarily uranium and thorium, has been studied as an analogue for the behaviour of transuranics in the far-field of a waste repository. The major findings of this study are: 1. the main process retarding uranium migration in the dispersion fan at Koongarra is sorption, which suppresses dissolved uranium concentrations well below solubility limits, with ferrihydrite being a major sorbing phase; 2. thorium is extremely immobile, with very low dissolved concentrations and corresponding high distribution ratios for 230Th. Overall, it is estimated that colloids are relatively unimportant in Koongarra groundwater. Uranium migrates mostly as dissolved species, whereas thorium and actinium are mostly adsorbed to larger, relatively immobile particles and the stationary phase. However, of the small amount of 230Th that passes through a 1μm filter, a significant proportion is associated with colloidal particles. Actinium appears to be slightly more mobile than thorium and is associated with colloids to a greater extent, although generally present in low concentrations. These results support the possibility of colloidal transport of trivalent and tetravalent actinides in the vicinity of a nuclear waste repository. 112 refs., 23 tabs., 32 figs

  17. Purification of cerium, neodymium and gadolinium for low background experiments

    Boiko R.S.

    2014-01-01

    Full Text Available Cerium, neodymium and gadolinium contain double beta active isotopes. The most interesting are 150Nd and 160Gd (promising for 0ν2β search, 136Ce (2β+ candidate with one of the highest Q2β. The main problem of compounds containing lanthanide elements is their high radioactive contamination by uranium, radium, actinium and thorium. The new generation 2β experiments require development of methods for a deep purification of lanthanides from the radioactive elements. A combination of physical and chemical methods was applied to purify cerium, neodymium and gadolinium. Liquid-liquid extraction technique was used to remove traces of Th and U from neodymium, gadolinium and for purification of cerium from Th, U, Ra and K. Co-precipitation and recrystallization methods were utilized for further reduction of the impurities. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe gamma spectrometry. As a result of the purification procedure the radioactive contamination of gadolinium oxide (a similar purification efficiency was reached also with cerium and neodymium oxides was decreased from 0.12 Bq/kg to 0.007 Bq/kg in 228Th, from 0.04 Bq/kg to <0.006 Bq/kg in 226Ra, and from 0.9 Bq/kg to 0.04 Bq/kg in 40K. The purification methods are much less efficient for chemically very similar radioactive elements like actinium, lanthanum and lutetium.

  18. Low background counting of 222Rn, 220Rn and 219Rn with electrostatic counters

    Mong, Brian; EXO-200 Collaboration; nEXO Collaboration

    2014-09-01

    The radon counting technique based on electrostatic precipitation of progenies in gas followed by alpha spectroscopy has been applied to support the material selection programs of low background, neutrino and dark matter experiments with emphasis on EXO. An array of 8 counters operated by Laurentian University at SNOLAB and the Waste Isolation Pilot Plant have reached the sensitivity of 10 atoms/day in the uranium, thorium and actinium chains. Hardware improvements are underway to further increase the capacity and sensitivity in support of nEXO. The radon counting technique based on electrostatic precipitation of progenies in gas followed by alpha spectroscopy has been applied to support the material selection programs of low background, neutrino and dark matter experiments with emphasis on EXO. An array of 8 counters operated by Laurentian University at SNOLAB and the Waste Isolation Pilot Plant have reached the sensitivity of 10 atoms/day in the uranium, thorium and actinium chains. Hardware improvements are underway to further increase the capacity and sensitivity in support of nEXO. Supported by NSERC Project Grants ``Search for Double Beta Decay with EXO.''

  19. Purification of cerium, neodymium and gadolinium for low background experiments

    Boiko, R. S.; Barabash, A. S.; Belli, P.; Bernabei, R.; Cappella, F.; Cerulli, R.; Danevich, F. A.; Incicchitti, A.; Laubenstein, M.; Mokina, V. M.; Nisi, S.; Poda, D. V.; Polischuk, O. G.; Tretyak, V. I.

    2014-01-01

    Cerium, neodymium and gadolinium contain double beta active isotopes. The most interesting are 150Nd and 160Gd (promising for 0ν2β search), 136Ce (2β+ candidate with one of the highest Q2β). The main problem of compounds containing lanthanide elements is their high radioactive contamination by uranium, radium, actinium and thorium. The new generation 2β experiments require development of methods for a deep purification of lanthanides from the radioactive elements. A combination of physical and chemical methods was applied to purify cerium, neodymium and gadolinium. Liquid-liquid extraction technique was used to remove traces of Th and U from neodymium, gadolinium and for purification of cerium from Th, U, Ra and K. Co-precipitation and recrystallization methods were utilized for further reduction of the impurities. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe gamma spectrometry. As a result of the purification procedure the radioactive contamination of gadolinium oxide (a similar purification efficiency was reached also with cerium and neodymium oxides) was decreased from 0.12 Bq/kg to 0.007 Bq/kg in 228Th, from 0.04 Bq/kg to <0.006 Bq/kg in 226Ra, and from 0.9 Bq/kg to 0.04 Bq/kg in 40K. The purification methods are much less efficient for chemically very similar radioactive elements like actinium, lanthanum and lutetium.

  20. AcEST: BP916351 [AcEST

    Full Text Available YMU001_000086_F12 527 Adiantum capillus-veneris mRNA. clone: YMU001_000086_F12. BP916351 CL1202C ... QLLFGIEKGTELLDVVRPAGSPLVDNWDCL 430 Query: 234 KAMVQAFE DHCGLLTSYGLKHMRAFANICNAGVDVCKMERVCSDVC 371 K MV+ FE ... KILFGISRGPEVLNKVRSAGQPLVDDWNCL 431 Query: 234 KAMVQAFE DHCGLLTSYGLKHMRAFANICNAGVDVCKMERVCSDVC 371 K V+AFE ... HCG L+ YG+KHMR+FANICNAG+ + +ME S C Sbjct: 432 KNQVRAFE RHCGSLSQYGIKHMRSFANICNAGIQMEQMEEAASQAC 477 Score = ... KLLFGIEKGPEILNTVRPAGQPLVDDWGCL 431 Query: 234 KAMVQAFE DHCGLLTSYGLKHMRAFANICNAGVDVCKMERVCSDVCD 374 K++V+ F ...

  1. Dicty_cDB: Contig-U09091-1 [Dicty_cDB

    Full Text Available 53 Score = 180 bits (91), Expect = 1e-45 Identities = 253/253 (100%) Strand = Plus / Plus Query: 234 tcccnat...ntanactaccnctggncaaantaaaactggtttngcnccnantgcaancggnt 293 |||||||||||||||||||||||...||||||||||||||||||||||||||||||||||||| Sbjct: 234 tcccnatntanactaccnctggncaaantaaaactggtttngcnccnantgcaancggn...acncgncnttggangnattgga 413 Query: 414 aancngnccttttaggggcnggnttancnggntttgcccnaaa...nttanttggnaannattggacncgncnttgg 152 Query: 404 angnattggaaancngnccttttaggggcnggnttancnggntttgcccna

  2. Drug: D00505 [KEGG MEDICUS

    Full Text Available D00505 Drug Phenelzine sulfate (USP); Nardil (TN) C8H12N2. H2SO4 234.0674 234.2728 D00505.gif Antidepress...129) Dopaminergic synapse map07027 Antidepressants map07216 Catecholamine transfe... Phenelzine sulfate (USP) USP drug classification [BR:br08302] Antidepressants Mo

  3. Evaluation of antioxidant activity of medicinal plants containing polyphenol compounds. Comparison of two extraction systems

    Kratchanova, M.; Denev, P.; Číž, Milan; Lojek, Antonín; Mihailov, A.

    2010-01-01

    Roč. 57, č. 2 (2010), s. 229-234. ISSN 0001-527X R&D Projects: GA MŠk(CZ) OC08058 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : medicinal plants * ORAC * polyphenols Subject RIV: BO - Biophysics Impact factor: 1.234, year: 2010

  4. 77 FR 38747 - Reports by Air Carriers on Incidents Involving Animals During Air Transport

    2012-06-29

    ... Privacy Act statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you may... implementing section 710 of AIR-21. See 68 FR 47798. The rule required air carriers that provide scheduled... regulations. See 70 FR 7392. The rule is codified at 14 CFR 234.13. Section 234.13 requires air carriers...

  5. AcEST: DK960456 [AcEST

    Full Text Available +1 Query: 121 AVCMRCK--VNFKGLERWIRSSQSPEEWRVGKPIRGIRNM 234 A+ + C +N KG E E+WR GKP+R +RNM Sbjct: 504 ALALNCHSPINE...WRVGKPIRGIRNM 234 A+ + C +N KG E E+WR GKP+R +RNM Sbjct: 512 ALALNCHSPINEKGAEA----

  6. Home Health Care and Discharged Hospice Care Patients: United States, 2000 and 2007

    ... 239) Malignant neoplasm . . . . . . . . . . . . . . .(140–208,230–234) Endocrine, nutritional, and metabolic diseases and immunity disorders . . . . . . . . . . . . . . . . . . . . . . . . . . . .(240–279) Diabetes mellitus. . . . . . . . . . . . . . . . . . . . . . . . . .(250) ... 198.7,198.82–199,230–234) Endocrine, nutritional, and metabolic diseases and immunity disorders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .(240–279) Diabetes mellitus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .(250) ...

  7. EST Table: FS735977 [KAIKOcDNA[Archive

    Full Text Available FS735977 E_FL_bmmt_04J24_R_0 11/12/09 n.h 10/09/28 36 %/182 aa ref|XP_001865897.1| best...rophin 2,3,4 [Culex quinquefasciatus] gb|EDS42461.1| bestrophin 2,3,4 [Culex quinquefasciatus] 10/09/03

  8. EST Table: FY748702 [KAIKOcDNA[Archive

    Full Text Available FY748702 E_FL_famL_39P03_F_0 11/11/04 79 %/157 aa ref|XP_001656347.1| bestrophin 2,...3,4 [Aedes aegypti] gb|EAT45610.1| bestrophin 2,3,4 [Aedes aegypti] 11/11/04 63 %/157 aa FBpp0251679|DwilGK2

  9. Listing Triangles

    Björklund, Andreas; Pagh, Rasmus; Vassilevska Williams, Virginia;

    2014-01-01

    DOI added. Bibliographic info: Automata, Languages, and Programming Lecture Notes in Computer Science Volume 8572, 2014, pp 223-234 /PFOR 06-01-2015......DOI added. Bibliographic info: Automata, Languages, and Programming Lecture Notes in Computer Science Volume 8572, 2014, pp 223-234 /PFOR 06-01-2015...

  10. EST Table: FS908191 [KAIKOcDNA[Archive

    Full Text Available FS908191 E_FL_fufe_13H10_F_0 10/09/28 76 %/234 aa ref|XP_970542.1| PREDICTED: similar to brix...B12626-PA 10/09/10 76 %/234 aa gi|91090402|ref|XP_970542.1| PREDICTED: similar to brix domain-containing protein 2 [Tribolium castaneum] FS911686 fufe ...

  11. 14 CFR 399.81 - Unrealistic or deceptive scheduling.

    2010-01-01

    ... Part 234 of Department regulations (14 CFR Part 234). (2) For the purposes of this section, a... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Unrealistic or deceptive scheduling. 399.81... Unrealistic or deceptive scheduling. (a) It is the policy of the Board to consider unrealistic scheduling...

  12. Spina Bifida Clinic Directory

    ... 798,163.html Back to top Missouri Children’s Mercy Hospital & Clinics Spinal Defects Clinic (pediatric only-will ... 234-3790 or (816) 234 3005 www.childrens-mercy.org/ Cardinal Glennon Children’s Medical Center Myelomeningocele Clinic ( ...

  13. Gene : CBRC-TSYR-01-1411 [SEVENS

    Full Text Available CBRC-TSYR-01-1411 Novel UN B UNKNOWN ALS_HUMAN 6e-12 18% ref|YP_002824783.1| conserved hypotheti ... l protein, contains ice nucleation protein domain [Rhizobium ... sp. NGR234] gb|ACP24030.1| conserved hypothetical ... protein, contains ice nucleation protein domain [Rhizobium ... sp. NGR234] 7e-47 19% MPSNRLVAVPSNRLVAVPSNQLVAVPSS ...

  14. Purification system of gram-amount neptunium using anion exchange chromatography

    To develop a purification system of gram-amount neptunium using anion exchange chromatography, adsorption elution of excess amount of actinium in 6M HNO3 aqueous solution was studied using thorium and uranium tracer. The partition coefficient (Kd) of Th (IV) decreased from Kd=99.1 of tracer to Kd=44.0, 5% load. By decreasing the partition coefficient, we can wash until 30 Vs under the purification conditions of 1% load and 95% recovery. The retention volume of U (IV) was about 300 Vs, a large value. The partition coefficient of Np (IV) may be larger than it and the large amount of washable eluting solution may be obtained. Washing of impurity of 3d transition metal and actinide (VI) can be done until 20Vs. With washing of 150Vs, impurity of alkali earth metal, metals (III) and platinum group metals decreased less than 0.1%. (S.Y.)

  15. A francium-223 reservoir source

    By improving and accelerating a method which had been earlier tried for caesium-rubidium separation on a cellulose column, i.e. elution with 2N HCl-equilibrated phenol, the author succeeded in obtaining consecutive and quasi-selective elutions of francium-223, starting with actinium-227 fixed at the top of a small cellulose column to which ZrO2 had been added. The francium-223, rapidly eluted under pressure, is extracted by water while the phenol is extracted by ether; it can easily be cleared of any residual traces of radioactive contaminants (thallium-207, radium-223, thorium-227) by two consecutive BaSO4 precipitations. The preparation of a Fr223 solution (HCl-H2SO4) requires approximately 20 min; the time noted for Fr223 was closer to 22 than to 21 min. (author)

  16. Radionuclide interactions with marine sediments

    A critical review of the literature on the subject of the interactions of radionuclides with marine sediments has been carried out. On the basis of the information available, an attempt has been made to give ranges and 'best estimates' for the distribution ratios between seawater and sediments. These estimates have been based on an understanding of the sediment seawater system and the porewater chemistry and mineralogy. Field measurements, laboratory measurements and estimates based on stable-element geochemical data are all taken into account. Laboratory measurements include distribution-ratio and diffusion-coefficient determinations. The elements reviewed are carbon, chlorine, calcium, nickel, selenium, strontium, zirconium, niobium, technetium, tin, iodine, caesium, lead, radium, actinium, thorium, protactinium, uranium, neptunium, plutonium, americium and curium. (author)

  17. Formerly utilized MED/AEC sites Remedial Action Program. Radiological survey of the St. Louis Airport Storage Site, St. Louis, Missouri. Final report

    Results of two radiological surveys of the St. Louis-Lambert Airport property, formerly known as the Airport Storage Site, St. Louis, Missouri, are presented. Uranium- and radium-bearing waste materials were stored from the 1940's to the late 1960's in this area. The surveys included direct measurements of beta-gamma radiation; determination of uranium, actinium, and radium concentrations in soil samples and from bore holes; determination of radionuclide concentrations in groundwater and surface water; measurement of radon flux from the ground surface; and measurements of 222Rn in air near the site. Results indicate that some offsite drainage pathways are becoming contaminated, probably by runoff from the site; no migration of 222Rn from the site was observed

  18. JAEA thermodynamic database for performance assessment of geological disposal of high-level and TRU wastes. Refinement of thermodynamic data for trivalent actinoids and samarium

    Within the scope of the JAEA thermodynamic database project for performance assessment of geological disposal of high-level radioactive and TRU wastes, the refinement of the thermodynamic data for the inorganic compounds and complexes of trivalent actinoids (actinium(III), plutonium(III), americium(III) and curium(III)) and samarium(III) was carried out. Refinement of thermodynamic data for these elements was based on the thermodynamic database for americium published by the Nuclear Energy Agency in the Organisation for Economic Co-operation and Development (OECD/NEA). Based on the similarity of chemical properties among trivalent actinoids and samarium, complementary thermodynamic data for their species expected under the geological disposal conditions were selected to complete the thermodynamic data set for the performance assessment of geological disposal of radioactive wastes. (author)

  19. Theoretical Study on Properties of New Isotope 265Bh

    2006-01-01

    The properties of nuclei belonging to the newly observed α-decay chain starting from 265Bh have been studied. The axially deformed relativistic mean-field calculation with the force NL-Z2 has been performed in the blockedBCS approximation. Some ground state properties such as binding energies, deformations, spins, and parities, as well as Q-values of the α-decay for this decay chain have been calculated and compared with known experimental data. Good agreement is found. The single-particle spectrum of the nucleus 265 Bh is studied and some new magic numbers are found,while the magnitudes of the shell gaps in superheavy nuclei are much smaller than those of nuclei before the actinium region, and the Fermi surfaces are close to the continuum. Thus the superheavy nuclei are usually not stable. The The methods which give good agreement with the data are selected.

  20. Proposed training program for construction personnel involved in remedial action work at sites contaminated by naturally occurring radionuclides

    Many sites used during the early days of the US atomic energy program are contaminated with radionuclides of the primordial decay chains (uranium, thorium, and actinium series). This contamination consists of residues resulting from refining and processing uranium and thorium. Preparation of these sites for release to unrestricted private use will involve the assistance of construction workers, many of whom have limited knowledge of the hazards associated with radioactive materials. Therefore, there is a need to educate these workers in the fundamentals of radioactive material handling to minimize exposures and possible spread of contamination. This training should disseminate relevant information at an appropriate educational level and should instill a cautious, common-sense attitude toward the handling of radioactive materials. The training should emphasize basic information concerning environmental radiation within a context of relative risk. A multi-media format, including colorful visual aids, demonstration, and discussion, should be used to maximize motivation and retention. A detailed, proposed training program design is presented

  1. Origin of elements of the Uranium-235 family observed in the Ellez river near the EL-4 experimental nuclear reactor in dismantling (Monts d'Arree- Finistere department); Origine des elements de la famille de l'uranium-235 observes dans la riviere Ellez a proximite du reacteur nucleaire experimental EL4 en cours de demantelement (Mont d'Arree - departement du Finistere). Resultats et premiers constats annee 2006

    NONE

    2006-07-01

    In a previous study which concerned the catchment basin of the harbour of Brest, the A.C.R.O. put in evidence a marking by artificial radioelements around the power plant of Brennilis which can be imputed without ambiguities to the nuclear installation. It also put in evidence abnormalities concerning the natural radioactivity which justifies this new study. In the area of the Monts d'Arree, actinium 227 ({sup 227}Ac), non born by its ascendents which are {sup 235}U and {sup 231}Pa is observed. This phenomenon is characterized by mass activities superior to these ones of {sup 235}U and able to reach these ones of {sup 238}U. Its presence corresponds with the drainage of the Ellez river since the former channel of radioactive effluents releases from the nuclear power plant EL-4 up to the reservoir Saint-Herblot situated 6 km downstream. The strongest values of radioactivity are registered near the disused power plant, at this place a relationship exists between the level of actinium 227 and this one of the artificial radioactivity as it exists a relationship with the decay products of radon exhaled from the subsoil ({sup 210}Pb). But its presence is not limited to a part of the Ellez river, it is equally observed in terrestrial medium, in places in priori not influenced by the direct liquid effluents of the power plant. This place is situated at more than 4 km and without any connection with the Ellez waters. At this stage of the study, it is not possible to answer with certainty the question of the origin of this phenomenon. A new reorientation is considered indispensable to clarify definitively the origin of this unknown phenomenon in the scientific publications and the environmental monitoring. (N.C.)

  2. origin of elements of the Uranium-235 family observed in the Ellez river near the EL-4 experimental nuclear reactor in dismantling (Monts d'Arree- Finistere department)

    In a previous study which concerned the catchment basin of the harbour of Brest, the A.C.R.O. put in evidence a marking by artificial radioelements around the power plant of Brennilis which can be imputed without ambiguities to the nuclear installation. It also put in evidence abnormalities concerning the natural radioactivity which justifies this new study. In the area of the Monts d'Arree, actinium 227 (227Ac), non born by its ascendents which are 235U and 231Pa is observed. This phenomenon is characterized by mass activities superior to these ones of 235U and able to reach these ones of 238U. Its presence corresponds with the drainage of the Ellez river since the former channel of radioactive effluents releases from the nuclear power plant EL-4 up to the reservoir Saint-Herblot situated 6 km downstream. The strongest values of radioactivity are registered near the disused power plant, at this place a relationship exists between the level of actinium 227 and this one of the artificial radioactivity as it exists a relationship with the decay products of radon exhaled from the subsoil (210Pb). But its presence is not limited to a part of the Ellez river, it is equally observed in terrestrial medium, in places in priori not influenced by the direct liquid effluents of the power plant. This place is situated at more than 4 km and without any connection with the Ellez waters. At this stage of the study, it is not possible to answer with certainty the question of the origin of this phenomenon. A new reorientation is considered indispensable to clarify definitively the origin of this unknown phenomenon in the scientific publications and the environmental monitoring. (N.C.)

  3. Physical Measurements and Clinical Findings of Persons with Radium Burdens

    Results of physical measurements and some clinical findings of persons with radium burdens are reported and discussed. Ten workers of the dial painting industry, two chemists, who have been working for between 10 and 20 yr in the radium- industry, one technician, who has been- working for over 20 yr with high-emanation radium preparations and one person with high radium intake of rather unknown history were measured in a whole-body counter for evaluation of the body burdens of radium-226 and radium-228+ actinium-228. In some cases the radon concentration of expired air was also measured. For four of the measured persons the radium-226 burden is of the order of the maximum permissible amount (MPA : 10-7 c) or more. In one case the burden amounts to more than three times the MPA, (3.4 x 10-7 c), in another case to more than 100 times the MPA (160 x 10-7 c). In one case the radium-228 + actinium-228 burden exceeds the MPA (6 x 10-8 c in bone). The measured radon concentrations in the expired air were used to calculate the excretion rate of radon. The average was 67%. Clinical findings with some of the measured persons are related to the measured body burdens. The patient with the high body burden of 160 x 10-7 c radium-226 shows heavy bone changes leading to spontaneous bone fractures. The blood picture shows a decrease in the number of erythrocytes and a low haemoglobin content but puncture of the sternum indicates normal haematopoiesis. It seems that the low number of erythrocytes is caused by chronic nephropathia, the reason for which might be an additional intake of uranium because.uranium was found in the urine by gamma spectroscopy. The results are discussed with respect to the MPA of radium-226 recommended by the International Commission on Radiological Protection. (author)

  4. Gastrointestinal absorption of uranium in man

    A method has been established for determining the fractional absorption of uranium directly in man. Measurements are made of the urinary excretion rates of uranium for individuals whose drinking water has a high 234U to 238U activity ratio and is the primary source of 234U in their diets. For two individuals, the values obtained for the fractional absorption of 234U were 0.004 and 0.006. The values obtained for the fractional absorption of 238U, using a literature value for the 238U intake from food, were 0.008 and 0.015. The present ICRP value is 0.20. 7 references, 1 table

  5. Toward a radiometric ice clock: uranium ages of the Dome C ice core

    Aciego, S.; Institute of Geochemistry and Petrology, ETH Zurich, Switzerland; Bourdon, B.; Department of Geological Sciences, University of Michigan, Ann Arbor, MI, USA; Schwander, J.; Climate and Environmental Physics, Physics Institute, University of Bern, Switzerland; Baur, H.; Institute of Geochemistry and Petrology, ETH Zurich, Switzerland; Forieri, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia

    2011-01-01

    Ice sheets and deep ice cores have yielded a wealth of paleoclimate information based on continuous dating methods while independent radiometric ages of ice have remained elusive. Here we demonstrate the application of (234U/238U) measurements to dating the EPICA Dome C ice core based on the accumulation of 234U in the ice matrix from recoil during 238U decay out of dust bound within the ice. Measured (234U/238U) activity ratios within the ice generally increase with depth while the surface a...

  6. Soil biochemical activity and phosphorus transformations and losses from acidified forest soils

    Šantrůčková, Hana; Vrba, Jaroslav; Picek, T.; Kopáček, Jiří

    2004-01-01

    Roč. 36, - (2004), s. 1569-1576. ISSN 0038-0717 Institutional research plan: CEZ:AV0Z6066911 Keywords : phosphatase * microbial P * C mineralisation Subject RIV: EH - Ecology, Behaviour Impact factor: 2.234, year: 2004

  7. Bias Corrected Spatially Downscaled Monthly CMIP5 Climate Projections

    U.S. Geological Survey, Department of the Interior — This archive contains 234 projections of monthly BCSD CMIP5 projections of precipitation and monthly means of daily-average, daily maximum and daily minimum...

  8. DESIGN AND DEVELOPMENT OF LEVOFLOXACIN HEMIHYDRATE FAST DISSOLVING TABLETS USING FENUGREEK POWDER

    Naveen chakravarthi.B

    2012-12-01

    Full Text Available Levofloxacin hemihydrate is an antibiotic used for bacterial infections. It belongs to flouroquinolones class. Fast dissolving tablets gaining popularity over conventional tablets due to their convenience in administration and suitability for patients like geriatrics and pediatric patients because of their swallowing difficulties. The half-life of the drug is 6-8 hrs and it is rapidly and completely absorbed after oral use for that levofloxacin prepared as fast dissolving tablets. Tablets were prepared by direct compression technique by using MCC as binder. Super disintegrants used are SSG(2%,3%,4% and 5%,CCS(AC-DI-SOL (2%,3%,4%and 5%, CP(2%,3%,4%and5%and FGP(2%,3%,4%and 5%,.Among these 4 super disintegrants, Fenugreek powder (FGP was show best results in the evaluation tests.

  9. Partial Molar Volumes of Air-Component Gases in Several Liquid n-Alkanes and 1-Alkanols at 313.15 K

    Izák, Pavel; Cibulka, I.; Heintz, A.

    1995-01-01

    Roč. 109, č. 2 (1995), s. 227-234. ISSN 0378-3812 Keywords : data density * partial molar volume * gas-liquid mixture Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.024, year: 1995

  10. Faecalibacterium prausnitzii Strain HTF-F and Its Extracellular Polymeric Matrix Attenuate Clinical Parameters in DSS-Induced Colitis

    Rossi, O.; Khan, M.T.; Schwarzer, Martin; Hudcovic, Tomáš; Šrůtková, Dagmar; Duncan, S.H.; Stolte, E.H.; Kozáková, Hana; Flint, H. J.; Samson, J.M.; Harmsen, H.J.M.; Wells, J. M.

    2015-01-01

    Roč. 10, č. 4 (2015). E-ISSN 1932-6203 Institutional support: RVO:61388971 Keywords : COMMENSAL BACTERIUM * DENDRITIC CELLS * MICROBIOTA Subject RIV: EC - Immunology Impact factor: 3.234, year: 2014

  11. 19 CFR 141.61 - Completion of entry and entry summary documentation.

    2010-04-01

    ... Statistical Note 1(b)(ii), HTSUS, except Canadian rail and truck charges, he must place either “(estimate... 15422(a) of the Food, Conservation, and Energy Act of 2008 (Pub. L. 110-234), for all goods entered...

  12. Fragment properties from fission of actinide nuclei induced by 6-10 MeV bremsstrahlungI

    Gook, A.; Eckardt, C.; Enders, J.; Freudenberger, M.; von Neumann-Cosel, P.; Oberstedt, A.; Oberstedt, S.; Richter, A.

    Experiments to investigate the photon-induced fission of actinide nuclei at excitation energies in the vicinity of the fission barrier are carried out at the superconducting Darmstadt linear electron accelerator S-DALINAC. A twin-Frisch-grid ionization chamber is used to deduce mass, total kinetic energy, and angular distributions of the fission fragments. First experiments on 238U and 234U have shown that the experimental setup provides excellent conditions for investigating low-energy bremsstrahlung induced fission. Further experiments on 234U and 232Th are currently in progress. In this contribution results from the first experiment on fission fragment mass and total kinetic energy distributions from 234,238U are presented along with preliminary data from an on-going investigation of angular distributions from 234U(γ, f)

  13. Ten-Competence: Life-Long Competence Development and Learning

    Koper, Rob; Specht, Marcus

    2006-01-01

    Koper, R., & Specht, M. (2008). Ten-Competence: Life-Long Competence Development and Learning. In M-A. Cicilia (Ed.), Competencies in Organizational e-learning: concepts and tools (pp. 234-252). Hershey: IGI-Global.

  14. Androgüüni kummaline pilk : fotograaf Ly Lestberg uurib androgüüni motiivi kaudu inimese hinge / Kärt Hellerma

    Hellerma, Kärt, 1956-

    1999-01-01

    Kunstnik-fotograafi Ly Lestbergi näitus "Insomnia" Raatuse galeriis ja Cafe Anglais: 9 mustvalget suureformaadilist fotot noorest naisest. Ilmunud ka kogumikus: Avanenud ruum / Kärt Hellerma. Tallinn, 2006, lk. 232-234

  15. Combining Rational and Random Strategies in beta-Glucosidase Zm-p60.1 Protein Library Construction

    Turek, D.; Klimeš, P.; Mazura, P.; Brzobohatý, Břetislav

    -, SEP2014 (2014). E-ISSN 1932-6203 Institutional support: RVO:68081707 Keywords : SUBSTRATE AGLYCONE SPECIFICITY * CRYSTAL-STRUCTURES * MAIZE Subject RIV: BO - Biophysics Impact factor: 3.234, year: 2014

  16. Synthesis, characterization and antibacterial activity of new fluorescent chitosan derivatives

    Přichystalová, H.; Almonasy, N.; Abdel-Mohsen, A. M.; Abdel-Rahman, R. M.; Fouda, M. M. G.; Vojtova, L.; Kobera, Libor; Spotz, Z.; Burgert, L.; Jancar, J.

    2014-01-01

    Roč. 65, April (2014), s. 234-240. ISSN 0141-8130 Institutional support: RVO:61389013 Keywords : chitosan derivatives * fluorescence * antibacterial activity Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.858, year: 2014

  17. Historie v uvozovkách: Pár poznámek k myšlení Marjorie Garberové

    Müller, Richard

    2012-01-01

    Roč. 60, č. 2 (2012), s. 225-234. ISSN 0009-0468 Institutional support: RVO:68378068 Keywords : history * new historicism * cultural studies * quotation * psychoanalysis * deconstruction * bisexuality * transvestism * Garber, Marjorie Subject RIV: AJ - Letters, Mass-media, Audiovision

  18. High Resolution Stellar Spectroscopy with VBT Echelle Spectrometer

    N. Kameswara Rao; S. Sriram; K. Jayakumar; F. Gabriel

    2005-06-01

    The optical design and performance of the recently commissioned fiber fed echelle spectrometer of 2.34 meter Vainu Bappu Telescope are described. The use of it for stellar spectroscopic studies is discussed.

  19. Pediatric Palliative Care: A Personal Story

    Full Text Available ... count__/__total__ Find out why Close Pediatric Palliative Care: A Personal Story NINRnews Subscribe Subscribed Unsubscribe 234 ... and her family. The story demonstrates how palliative care can positively influence a patient's and family's experience ...

  20. Drug: D03238 [KEGG MEDICUS

    Full Text Available nts 234 Antacids 2343 Aluminum-containing agents D03238 Hydrotalcite (JAN/INN) Anat...07038 Antiulcer drugs Therapeutic category of drugs in Japan [BR:br08301] 2 Agents affecting individual organs 23 Digestive organ age