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Sample records for 245cm nejtronnye secheniya

  1. Synthesis of the isotopes of elements 118 and 116 in the 249Cf and 245Cm+48Ca fusion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Oganessian, Y T; Utyonkov, V K; Lobanov, Y V; Abdullin, F S; Polyakov, A N; Sagaidak, R N; Shirokovsky, I V; Tsyganov, Y S; Voinov, A A; Gulbekian, G G; Bogomolov, S L; Gikal, B N; Mezentsev, A N; Iliev, S; Subbotin, V G; Sukhov, A M; Subotic, K; Zagrebaev, V I; Vostokin, G K; Itkis, M G; Moody, K J; . Patin, J B; Shaughnessy, D A; Stoyer, M A; Stoyer, N J; Wilk, P A; Kenneally, J M; Landrum, J H; Wild, J F; Lougheed, R W

    2006-01-31

    The decay properties of {sup 290}116 and {sup 291}116, and the dependence of their production cross sections on the excitation energies of the compound nucleus, {sup 293}116, have been measured in the {sup 245}Cm({sup 48}Ca,xn){sup 293-x}116 reaction. These isotopes of element 116 are the decay daughters of element 118 isotopes, which are produced via the {sup 249}Cf+{sup 48}Ca reaction. They performed the element 118 experiment at two projectile energies, corresponding to {sup 297}118 compound nucleus excitation energies of E* = 29.2 {+-} 2.5 and 34.4 {+-} 2.3 MeV. During an irradiation with a total beam dose of 4.1 x 10{sup 19} {sup 48}Ca projectiles, three similar decay chains consisting of two or three consecutive {alpha} decays and terminated by a spontaneous fission (SF) with high total kinetic energy of about 230 MeV were observed. The three decay chains originated from the even-even isotope {sup 294}118 (E{sub {alpha}} = 11.65 {+-} 0.06 MeV, T{sub {alpha}} = 0.89{sub -0.31}{sup +1.07} ms) produced in the 3n-evaporation channel of the {sup 249}Cf+{sup 48}Ca reaction with a maximum cross section of 0.5{sub -0.3}{sup +1.6} pb.

  2. Fission Cross-section Measurements of (233)U, (245)Cm and (241,243)Am at CERN n_TOF Facility

    CERN Document Server

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

    2011-01-01

    Neutron-induced fission cross-sections of minor actinides have been measured using the n_TOF white neutron source at CERN, Geneva, as part of a large experimental program aiming at collecting new data relevant for nuclear astrophysics and for the design of advanced reactor systems. The measurements at n_TOF take advantage of the innovative features of the n_TOF facility, namely the wide energy range, high instantaneous neutron flux and good energy resolution. Final results on the fission cross-section of 233U, 245Cm and 243Am from thermal to 20 MeV are here reported, together with preliminary results for 241Am. The measurement have been performed with a dedicated Fast Ionization Chamber (FIC), a fission fragment detector with a very high efficiency, relative to the very well known cross-section of 235U, measured simultaneously with the same detector.

  3. Measurement of the Neutron Capture Cross Sections of $^{233}$U, $^{237}$Np, $^{240,242}$Pu, $^{241,243}$Am and $^{245}$Cm with a Total Absorption Calorimeter at n_TOF

    CERN Multimedia

    Beer, H; Wiescher, M; Cox, J; Rapp, W; Embid, M; Dababneh, S

    2002-01-01

    Accurate and reliable neutron capture cross section data for actinides are necessary for the poper design, safety regulation and precise performance assessment of transmutation devices such as Fast Critical Reactors or Accelerator Driven Systems (ADS). The goal of this proposal is the measurement of the neutron capture cross sections of $^{233}$U, $^{237}$Np, $^{240,242}$Pu, $^{241,243}$Am and $^{245}$Cm at n_TOF with an accuracy of 5~\\%. $^{233}$U plays an essential role in the Th fuel cycle, which has been proposed as a safer and cleaner alternative to the U fuel cycle. The capture cross sections of $^{237}$Np,$^{240,242}$Pu, $^{241,243}$Am and $^{245}$Cm play a key role in the design and optimization of a strategy for the Nuclear Waste Transmutation. A high accuracy can be achieved at n_TOF in such measurements due to a combination of features unique in the world: high instantaneous neutron fluence and excellent energy resolution of the facility, innovative Data Acquisition System based on flash ADCs and t...

  4. Above-threshold structure in {sup 244}Cm neutron-induced fission cross section

    Energy Technology Data Exchange (ETDEWEB)

    Maslov, V.M. [Radiation Physics and Chemistry Problems Inst., Minsk-Sosny (Belarus)

    1997-03-01

    The quasi-resonance structure appearing above the fission threshold in neutron-induced fission cross section of {sup 244}Cm(n,f) is interpreted. It is shown to be due to excitation of few-quasiparticle states in fissioning {sup 245}Cm and residual {sup 244}Cm nuclides. The estimate of quasiparticle excitation thresholds in fissioning nuclide {sup 245}Cm is consistent with pairing gap and fission barrier parameters. (author)

  5. Above-threshold structure in {sup 244}Cm neutron-induced fission cross section

    Energy Technology Data Exchange (ETDEWEB)

    Maslov, V.M. [Radiation Physics and Chemistry Problems Inst., Minsk-Sosny (Belarus)

    1997-03-01

    The quasi-resonance structure appearing above the fission threshold in neutron-induced fission cross section of {sup 244}Cm(n,f) is interpreted. It is shown to be due to excitation of few-quasiparticle states in fissioning {sup 245}Cm and residual {sup 244}Cm nuclides. The estimate of quasiparticle excitation thresholds in fissioning nuclide {sup 245}Cm is consistent with pairing gap and fission barrier parameters. (author)

  6. Theoretical predictions on production of neutron-deficient nuclei with Z ≥ 93 in multinucleon transfer reactions

    Science.gov (United States)

    Zhu, Long; Su, Jun; Zhang, Feng-Shou

    2017-08-01

    Within the framework of dinuclear system model, the transfer reactions 58Ni + 233U, 58Ni + 238U, and 64Ni + 238U are investigated. The influences of projectile and target neutron numbers on cross sections of producing neutron-deficient actinide nuclei in transfer reactions are studied. It is found that the system 58Ni + 233U with smaller neutron excess is favorable to produce neutron-deficient nuclei. We predict the production cross sections of neutron-deficient nuclei with Z = 93- 98 in transfer reactions 58Ni + 233U and 40Ca + 245Cm with different incident energies. We find the transfer reactions 58Ni + 233U and 40Ca + 245Cm are feasible for producing neutron-deficient actinide nuclei in future experiments.

  7. Average resonance parameters evaluation for actinides

    Energy Technology Data Exchange (ETDEWEB)

    Porodzinskij, Yu.V.; Sukhovitskij, E.Sh. [Radiation Physics and Chemistry Problems Inst., Minsk-Sosny (Belarus)

    1997-03-01

    New evaluated <{Gamma}{sub n}{sup 0}> and values for {sup 238}U, {sup 237}Np, {sup 243}Cm, {sup 245}Cm, {sup 246}Cm and {sup 241}Am nuclei in the resolved resonance region are presented. The applied method based on the idea that experimental resonance missing results in correlated changes of reduced neutron widths and level spacings distributions is discussed. (author)

  8. Annual report of the project CIS-03-95, `evaluation of actinide nuclear data`

    Energy Technology Data Exchange (ETDEWEB)

    Maslov, V.M. [Radiation Physics and Chemistry Problems Inst., Minsk-Sosny (Belarus)

    1997-03-01

    The evaluation of neutron data for {sup 243}Cm, {sup 245}Cm and {sup 246}Cm is made in the energy region from 10-5 eV up to 20 MeV. The results of the evaluation are compiled in the ENDF/B-VI format. This work is performed under the Project Agreement CIS-03-95 with the International Science and Technology Center (Moscow). This is the annual report of the project CIS-03-95. (author)

  9. Measurements of Fission Cross Sections of Actinides

    CERN Multimedia

    Wiescher, M; Cox, J; Dahlfors, M

    2002-01-01

    A measurement of the neutron induced fission cross sections of $^{237}$Np, $^{241},{243}$Am and of $^{245}$Cm is proposed for the n_TOF neutron beam. Two sets of fission detectors will be used: one based on PPAC counters and another based on a fast ionization chamber (FIC). A total of 5x10$^{18}$ protons are requested for the entire fission measurement campaign.

  10. Annual report of the project CIS-03-95, `evaluation of actinide nuclear data`

    Energy Technology Data Exchange (ETDEWEB)

    Maslov, V.M. [Radiation Physics and Chemistry Problems Inst., Minsk-Sosny (Belarus)

    1997-03-01

    The evaluation of neutron data for {sup 243}Cm, {sup 245}Cm and {sup 246}Cm is made in the energy region from 10-5 eV up to 20 MeV. The results of the evaluation are compiled in the ENDF/B-VI format. This work is performed under the Project Agreement CIS-03-95 with the International Science and Technology Center (Moscow). This is the annual report of the project CIS-03-95. (author)

  11. Average resonance parameters evaluation for actinides

    Energy Technology Data Exchange (ETDEWEB)

    Porodzinskij, Yu.V.; Sukhovitskij, E.Sh. [Radiation Physics and Chemistry Problems Inst., Minsk-Sosny (Belarus)

    1997-03-01

    New evaluated <{Gamma}{sub n}{sup 0}> and values for {sup 238}U, {sup 237}Np, {sup 243}Cm, {sup 245}Cm, {sup 246}Cm and {sup 241}Am nuclei in the resolved resonance region are presented. The applied method based on the idea that experimental resonance missing results in correlated changes of reduced neutron widths and level spacings distributions is discussed. (author)

  12. Technical note: Test of a low-cost and animal-friendly system for measuring methane emissions from dairy cows

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Lund, Peter; Weisbjerg, Martin Riis;

    2012-01-01

    and validated. The system uses the same principles as systems for open-circuit indirect calorimetry, but to lower the costs, the chamber construction and air-conditioning system were simpler than described for other open-circuit systems. To secure the highest possible animal welfare, the system is located...... in the cow’s daily environment. The system consists of 4 transparent polycarbonate chambers placed in a square so that the cows are facing each other. The chamber dimensions are 183 (width), 382 (length), and 245cm (height) with a volume of 17 m3. Flow and concentrations of O2, CO2, CH4, and H2 are measured...

  13. Neutron induced fission cross section measurements aimed at nuclear technology development

    CERN Document Server

    Belloni, Francesca; Rui, R

    2010-01-01

    Neutron induced fission cross sections of 233U, 238U, 241Am, 243Am and 245Cm in the energy range between 500 keV and 20 MeV obtained at the n_TOF Neutron Time of Flight facility at CERN (Genève) are presented. Fission fragments had been detected by a gas counter with good discrimination between nuclear fission products and background events. A comparison between the extracted cross sections, previous experimental results and evaluated libraries is reported.

  14. Self-Powered Intelligent Sensor Node Concept for Monitoring of Road and Traffic Conditions

    Directory of Open Access Journals (Sweden)

    Sebastian Strache

    2012-03-01

    Full Text Available A promising approach for future road construction is based on a surface, which is manufactured in a production plant and can be unrolled on a conventional basis. This paper deals with an idea of making the road “intelligent” by integrating a net of sensor nodes. Equipped with acceleration sensors these systems can detect the actual traffic situation. With the knowledge of the exact position and velocity of each car a driver assistance system is able to find the fastest route or provide exact and reliable warnings to prevent e.g. accidents at the end of traffic jams. This paper describes the main idea of a low cost, energy harvesting sensor node containing a MEMS accelerometer with a frontend, a processing unit, a photovoltaic energy harvesting power supply and a wireless communication link. Measurements show that the detection of passing vehicles using structure borne sound and MEMS accelerometers is feasible. Furthermore the described functionality can be integrated into a size of less than 2.45 cm ´ 2.45 cm x 1 cm and each senor node can be operated stand alone.

  15. Detailed investigation of neutron emitters in the transmutation of Minor Actinides

    Energy Technology Data Exchange (ETDEWEB)

    Letourneau, A.; Bringer, O.; Dupont, E.; Panebianco, S.; Veyssiere, Ch. [CEA/Saclay/DSM/IRFU - Gif-sur-Yvette (France); Al Mahamid, I. [Wadsworth Center, New York State Department of Health, Albany, NY 12201 (United States); Chartier, F. [CEA/Saclay/DEN/DPC/SECR - Gif-sur-Yvette (France); Mutti, P. [Institut Laue-Langevin, Grenoble (France); Oriol, L. [CEA/Cadarache/DEN/DER/SPEX - Saint-Paul-lez-Durances (France)

    2008-07-01

    The production of neutron emitters during the incineration process of minor actinides could be very penalizing for the reprocessing of the targets when transmuted in heterogeneous mode, either in dedicated systems (ADS) or in generation IV reactors. Therefore their production has to be carefully evaluated. The reliability of such evaluation really depends on nuclear data (capture and fission cross sections) and their accuracy. In this paper we present a work we have done to investigate the production of neutron emitters in the incineration of {sup 237}Np and {sup 241}Am targets in fast and thermal nuclear reactor concepts. The impact of nuclear data uncertainties on the production of those neutron-emitters was evaluated by sensitivity calculations. The reduction for some of these uncertainties in the thermal energy region was done by measuring more precisely the {sup 244}Cm(n,gamma){sup 245}Cm, {sup 245}Cm(n,f) and {sup 249}Cf(n,gamma){sup 250}Cf capture cross sections at the Laue-Langevin Institute (ILL). It amounts to (15.6+-2.4) b for the first one, (1923+-49) b for the second and (389+-10) b for the third one. (authors)

  16. Ternary particles with extreme N/Z ratios from neutron-induced fission

    Energy Technology Data Exchange (ETDEWEB)

    Koster, U.; Faust, H.; Friedrichs, T.; Oberstedt, S.; Fioni, G.; Grob, M.; Ahmad, I. J.; Devlin, M.; Heinz, A.; Kondev, F. G.; Lauritsen, T.; Sarantites, D. G.; Siem, S.; Sobotka, L. G.; Sonzogni, A.

    2000-05-16

    The existing ternary fission models can well reproduce the yields of the most abundant light charged particles. However, these models tend to significantly overestimate the yields of ternary particles with an extreme N/Z ratio: {sup 3}He, {sup 11}Li, {sup 14}Be, etc. The experimental yields of these isotopes were investigated with the recoil separator LOHENGRIN down to a level of 10{sup {minus}10} per fission. Results from the fissioning systems {sup 233}U (n{sub th}, f), {sup 235}U(n{sub th},f), {sup 239}Pu(n{sub th},f) {sup 241}Pu(n{sub th},f) and {sup 245}Cm(n{sub th},f) are presented and the implications for the ternary fission models are discussed.

  17. EFFECTS OF SUBSTRATUM AND CONTAINERS IN ACCLIMATION OF PINEAPPLE SEEDLINGS [Ananas comosus (L. Merril] CV. PÉROLA EFEITOS DE SUBSTRATOS E RECIPIENTES NA ACLIMATAÇÃO DE PLÂNTULAS DE ABACAXIZEIRO [Ananas comosus (L. Merril] CV. PÉROLA

    Directory of Open Access Journals (Sweden)

    Sarah Brandão Santa Cruz Barboza

    2007-09-01

    Full Text Available

    After the removal of the in vitro culture medium, the survival and growth of micropropagated seedlings are among the main difficulties found in several crops. The objective of this study was to evaluate the behavior of pineapple cv. Pérola seedlings produced in vitro and acclimated in different substrates and containers. The experimental design was completely randomized split plot, with four replicates. The plots (twenty plants consisted of three substrates (sand/plant fiber/humus, Plantmax and sand and the subplots consisted of three containers (a tubet 5cm in diameter by 13cm high, a tubet 5cm in diameter by 24.5cm high and a 10cm x 8cm plastic bag. The combinations of sand/plant fiber/humus with 5x13cm tubet or with a plastic bag, and of Plantmax with 5x13cm tubet provide better growth in ex vitro conditions.

    KEY-WORDS: Culture in vitro; micropropagation; fruitculture.

    A sobrevivência e o crescimento de plântulas micropropagadas, após a remoção do meio de cultivo in vitro, estão entre as principais dificuldades encontradas em várias culturas. O objetivo deste trabalho foi avaliar o comportamento de plântulas de abacaxi cv. Pérola, produzidas in vitro e submetidas a aclimatação em diferentes substratos e recipientes. O delineamento experimental foi inteiramente ao acaso em parcelas subdivididas, com quatro repetições. As parcelas (com vinte plântulas foram constituídas de três substratos (areia/xaxim/húmus, Plantmax e areia e as subparcelas, de três recipientes (tubete com 5cm de diâmetro x 13cm de altura, tubete com 5cm de diâmetro x 24,5cm de altura e saco plástico, com 10cm x 8cm. As combinações areia/xaxim/húmus com tubete pequeno ou com saco plástico e Plantmax com tubete de 5cm diâmetro x 13cm de altura proporcionaram melhores respostas ao crescimento em condições ex vitro.

    PALAVRAS-CHAVE: Cultivo in vitro; micropropagação; fruticultura; parcelas subdivididas.

  18. Yields and spectroscopy of radioactive isotopes at LOHENGRIN and ISOLDE

    CERN Document Server

    Köster, U

    1999-01-01

    Yields of radioactive nuclei were measured at two facilities: the recoil separator LOHENGRIN at the Institut Laue Langevin in Grenoble and the on-line isotope separator ISOLDE at CERN in Geneva. At LOHENGRIN the yields of light charged particles were measured from thermal neutron induced ternary fission of several actinide targets: 233U, 235U, 239Pu, 241Pu and 245Cm. Thin targets are brought into a high neutron flux. The produced nuclei leave these with the recoil obtained in the fission reaction. They are measured at different energies and ionic charge states. After corrections for the experimental acceptance, the time behaviour of the fission rate and the ionic charge fraction, the yields are integrated over the kinetic energy distribution. Comparing these yields with the predictions of various ternary fission models shows that the most abundant nuclides are well reproduced. On the other hand the models overestimate significantly the production of more "exotic" nuclides with an extreme N/Z ratio. Therefore ...

  19. Measurement of fission cross-section of actinides at n_TOF for advanced nuclear reactors

    CERN Document Server

    Calviani, Marco; Montagnoli, G; Mastinu, P

    2009-01-01

    The subject of this thesis is the determination of high accuracy neutron-induced fission cross-sections of various isotopes - all of which radioactive - of interest for emerging nuclear technologies. The measurements had been performed at the CERN neutron time-of-flight facility n TOF. In particular, in this work, fission cross-sections on 233U, the main fissile isotope of the Th/U fuel cycle, and on the minor actinides 241Am, 243Am and 245Cm have been analyzed. Data on these isotopes are requested for the feasibility study of innovative nuclear systems (ADS and Generation IV reactors) currently being considered for energy production and radioactive waste transmutation. The measurements have been performed with a high performance Fast Ionization Chamber (FIC), in conjunction with an innovative data acquisition system based on Flash-ADCs. The first step in the analysis has been the reconstruction of the digitized signals, in order to extract the information required for the discrimination between fission fragm...

  20. Ecr Driven Multicusp Volume h- Source

    Science.gov (United States)

    Bacal, M.; Ivanov, A. A., Jr.; Rouille, C.; Bechu, S.; Pelletier, J.

    2004-11-01

    The plasma of the source is created by seven elementary multi-dipolar ECR sources (2.45GHz). Each of these sources consists of a permanent magnet mounted at the extremity of a coaxial feedthrough. This plasma is confined by a cylindrical multicusp configuration, which traps the hot electrons at the outer boundary of the system thus favoring the creation of optimum plasma conditions necessary for H^- generation (in particular, the electron temperature of the order of 0.6 1.0 eV). We studied the density and temperature of the plasma and of the hydrogen negative ions in the center of the source, as well as the extracted currents, in the pressure range 1 to 4 mTorr, with a microwave power of 1 kW. The negative ion density measured at 4.5 to 9.5 cm from the ECR sources is going up with pressure, while the extracted current (measured at 19.5 to 24.5 cm from the sources) attains a maximum at 1.5 mTorr. Approaching the multi-dipolar sources to the extractor leads to the increase of the extracted negative ion current. Tantalum evaporation also leads to the increase of the extracted negative ion current . The effect of a collar in front of the plasma electrode will also be described. . The support of EEC (Contract HPRI-CT-2001-50021) is gratefully acknowledged.

  1. REPRODUCTIVE CHARACTERISTICS OF INDONESIA MAHSEER (Tor tambroides, Bleeker, 1854, IN TWO DIFFERENT RIVERS IN WESTERN SUMATERA

    Directory of Open Access Journals (Sweden)

    Arif Wibowo

    2014-12-01

    Full Text Available The reproductive characteristics of mahseer, Tor. tambroides, were studied in Manna River and Batang Tarusan River, which are located on each side of Western Sumatera River. The reproductive period of T. tambroides is largely consistent with that described for the species in other areas, however monthly variations in the extent and timing of peak spawning are recorded. The analysis of the sex ratio indicates an increase in the percentage of females with size, more marked in largest sizes. Seasonal patterns in the occurrences of spawning showed that the spawning season in Manna River lasted was similar with that in Batang Tarusan River, although a second prominent increase of GSI was observed in April and September in Manna River, meanwhile the GSI of Batang Tarusan River fish were below 2 without an apparent variation. L50s of Manna River and Batang Tarusan River mahseer were estimated as 24.5 cm and 20.66 cm, respectively, indicating a high variability in size at first maturity of the mahseer population. Our study provides some important information on the reproductive biology of T. tambroides that will be helpful in similar studies and contributed to fisheries management of this species.

  2. Reinvestigation of the α-decays of 249Cf and 233U

    Science.gov (United States)

    Aka, A. Koua; Ardisson, G.; Barci, V.; El Samad, O.; Trubert, D.; Ahmad, I.

    1996-02-01

    The alpha-particle decay of 249Cf has been reinvestigated using coaxial and planar HPGe detectors. Energies and emission probabilities of thirty γ-rays were measured, of which nine are reported for the first time. All transitions have been included in the 245Cm level scheme suggested in this work: 14 excited states are found to be fed and assigned to 4 rotational bands. The Iπ = {11}/{2}- member of the {7}/{2} [743] Nilsson state was found to be fed at 772.3 keV. Alpha-particle transition probabilities were calculated from the revised 249Cf decay scheme. The alpha-particle decay of 233U has been reinvestigated using a UO 22+ source purified continuously from daughters by ion exchange chromatography. Energies and intensities of 178 γ-rays were determined, of which 49 are reported for the first time. γ-γ coincidence studies were also performed to help in the construction of the 229Th level scheme.

  3. The Fission Programme at the CERN n_TOF Facility

    Science.gov (United States)

    Tsinganis, A.; Barbagallo, M.; Berthoumieux, E.; Calviani, M.; Chiaveri, E.; Colonna, N.; Diakaki, M.; Duran, I.; Guerrero, C.; Gunsing, F.; Leal-Cidoncha, E.; Leong, L.-S.; Paradela, C.; Tarrio, D.; Tassan-Got, L.; Vlastou, R.

    Since 2001, the scientific programme of the CERN n_TOF facility has focused mainly on the study of radiative neutron capture reactions, which are of great interest to nuclear astrophysics and on neutron-induced fission reactions, which are of relevance for nuclear technology, as well as essential for the development of theoretical models of fission. In particular, taking advantage of the high instantaneous neutron flux and high energy resolution of the facility, as well as of high-performance detection and acquisition systems, accurate new measurements on several long-lived major and minor actinides, from 232Th to 245Cm, have been performed so far. Data on these isotopes are needed in order to improve the safety and efficiency of conventional reactors, as well as to develop new systems for nuclear energy production and treatment of nuclear waste, such as Generation IV reactors, Accelerator Driven Systems and reactors based on innovative fuel cycles. A review of the most important results on fission cross-sections and fragment properties obtained at n_TOF for a variety of (radioactive) isotopes is presented along with the perspectives arising from the coming on line in the second half of 2014 of a new 19 m flight-path, which will allow n_TOF to expand its measurement capabilities to even more rare or short-lived isotopes, such as 230Th, 232U, 238,240Pu and 244Cm.

  4. Low energy neutrons from a sup 2 sup 3 sup 9 PuBe isotopic neutron source inserting in moderating media

    CERN Document Server

    Vega, H R

    2002-01-01

    Several neutron applications share a common problem: the neutron source design. In this work MCNP computer code has been used to design a moderated sup 2 sup 3 sup 9 PuBe neutron source to produce low energy neutrons. The design involves the source located at the center of a spherical moderator. Moderator media studied were light water, heavy water and a heterogeneous combination of light water and heavy water. Similar moderating features were found between the 24.5 cm-radius container filled with heavy water (23.0-cm-thick) and that made with light water (3.5-cm-thick) plus heavy water (19.5-cm-thick). A sup 2 sup 3 sup 9 PuBe neutron source inserted in this moderator produces, at 27 cm, a neutron fluence of 1.8 x 10 sup - sup 4 n-cm sup - sup 2 per source neutron, with an average neutron energy of 0.34 MeV, where 47.8 % have an energy <= 0.4 eV. A further study of this moderator was carried out using a reflector medium made of graphite. Thus, 15-cm-thickness reflector improves the neutron field producing...

  5. Powering-up Wireless Sensor Nodes Utilizing Rechargeable Batteries and an Electromagnetic Vibration Energy Harvesting System

    Directory of Open Access Journals (Sweden)

    Salar Chamanian

    2014-10-01

    Full Text Available This paper presents a wireless sensor node (WSN system where an electromagnetic (EM energy harvester is utilized for charging its rechargeable batteries while the system is operational. The capability and the performance of an in-house low-frequency EM energy harvester for charging rechargeable NiMH batteries were experimentally verified in comparison to a regular battery charger. Furthermore, the power consumption of MicaZ motes, used as the WSN, was evaluated in detail for different operation conditions. The battery voltage and current were experimentally monitored during the operation of the MicaZ sensor node equipped with the EM vibration energy harvester. A compact (24.5 cm3 in-house EM energy harvester provides approximately 65 µA charging current to the batteries when excited by 0.4 g acceleration at 7.4 Hz. It has been shown that the current demand of the MicaZ mote can be compensated for by the energy harvester for a specific low-power operation scenario, with more than a 10-fold increase in the battery lifetime. The presented results demonstrate the autonomous operation of the WSN, with the utilization of a vibration-based energy harvester.

  6. Review and Assessment of Neutron Cross Section and Nubar Covariances for Advanced Reactor Systems

    Energy Technology Data Exchange (ETDEWEB)

    Maslov,V.M.; Oblozinsky, P.; Herman, M.

    2008-12-01

    In January 2007, the National Nuclear Data Center (NNDC) produced a set of preliminary neutron covariance data for the international project 'Nuclear Data Needs for Advanced Reactor Systems'. The project was sponsored by the OECD Nuclear Energy Agency (NEA), Paris, under the Subgroup 26 of the International Working Party on Evaluation Cooperation (WPEC). These preliminary covariances are described in two recent BNL reports. The NNDC used a simplified version of the method developed by BNL and LANL that combines the recent Atlas of Neutron Resonances, the nuclear reaction model code EMPIRE and the Bayesian code KALMAN with the experimental data used as guidance. There are numerous issues involved in these estimates of covariances and it was decided to perform an independent review and assessment of these results so that better covariances can be produced for the revised version in future. Reviewed and assessed are uncertainties for fission, capture, elastic scattering, inelastic scattering and (n,2n) cross sections as well as prompt nubars for 15 minor actinides ({sup 233,234,236}U, {sup 237}Np, {sup 238,240,241,242}Pu, {sup 241,242m,243}Am and {sup 242,243,244,245}Cm) and 4 major actinides ({sup 232}Th, {sup 235,238}U and {sup 239}Pu). We examined available evaluations, performed comparison with experimental data, taken into account uncertainties in model parameterization and made use state-of-the-art nuclear reaction theory to produce the uncertainty assessment.

  7. Extended-gate-type IGZO electric-double-layer TFT immunosensor with high sensitivity and low operation voltage

    Science.gov (United States)

    Liang, Lingyan; Zhang, Shengnan; Wu, Weihua; Zhu, Liqiang; Xiao, Hui; Liu, Yanghui; Zhang, Hongliang; Javaid, Kashif; Cao, Hongtao

    2016-10-01

    An immunosensor is proposed based on the indium-gallium-zinc-oxide (IGZO) electric-double-layer thin-film transistor (EDL TFT) with a separating extended gate. The IGZO EDL TFT has a field-effect mobility of 24.5 cm2 V-1 s-1 and an operation voltage less than 1.5 V. The sensors exhibit the linear current response to label-free target immune molecule in the concentrations ranging from 1.6 to 368 × 10-15 g/ml with a detection limit of 1.6 × 10-15 g/ml (0.01 fM) under an ultralow operation voltage of 0.5 V. The IGZO TFT component demonstrates a consecutive assay stability and recyclability due to the unique structure with the separating extended gate. With the excellent electrical properties and the potential for plug-in-card-type multifunctional sensing, extended-gate-type IGZO EDL TFTs can be promising candidates for the development of a label-free biosensor for public health applications.

  8. The hydrogen tunneling splitting in malonaldehyde: A full-dimensional time-independent quantum mechanical method

    Science.gov (United States)

    Wu, Feng; Ren, Yinghui; Bian, Wensheng

    2016-08-01

    The accurate time-independent quantum dynamics calculations on the ground-state tunneling splitting of malonaldehyde in full dimensionality are reported for the first time. This is achieved with an efficient method developed by us. In our method, the basis functions are customized for the hydrogen transfer process which has the effect of greatly reducing the size of the final Hamiltonian matrix, and the Lanczos method and parallel strategy are used to further overcome the memory and central processing unit time bottlenecks. The obtained ground-state tunneling splitting of 24.5 cm-1 is in excellent agreement with the benchmark value of 23.8 cm-1 computed with the full-dimensional, multi-configurational time-dependent Hartree approach on the same potential energy surface, and we estimate that our reported value has an uncertainty of less than 0.5 cm-1. Moreover, the role of various vibrational modes strongly coupled to the hydrogen transfer process is revealed.

  9. Transcatheter Arterial Embolization Alone for Giant Hepatic Hemangioma

    Science.gov (United States)

    Zhang, Yue-Lin; Zhou, Guan-Hui; Ai, Jing; Zhou, Tan-Yang; Zhu, Tong-Yin; Zhang, Ai-Bin; Wang, Wei-Lin; Zheng, Shu-Sen

    2015-01-01

    Giant hepatic hemangioma is a benign liver condition that may be treated using surgery. We studied the digital subtraction angiographic (DSA) characteristics of giant hepatic hemangioma, and the effectiveness of transcatheter arterial embolization (TAE) alone for its treatment. This was a retrospective study of 27 patients diagnosed with giant hepatic hemangioma and treated with TAE alone (using lipiodol mixed with pingyangmycin) at the Division of Hepatobiliary and Pancreatic Surgery, First Affiliated Hospital, Zhejiang University, between January 2010 and March 2013. The feeding arteries were identified using DSA. All patients were followed up for between three weeks and 12 months. Changes in tumor diameter and symptoms were observed. The 27 patients included had giant hepatic hemangiomas ranging from 5.3 to 24.5 cm (mean, 11.24±5.08 cm) in the right (n = 13), left (n = 1) or both (n = 13) lobes. Preoperative hepatic angiography showed multiple abnormal vascular lakes in the early phase, known as the “early leaving but late returning, hanging nut on a twig” sign. On the day after TAE, hepatic transaminase levels were increased (ALT: 22.69±17.95 to 94.88±210.32 U/L; ALT: 24.00±12.37 to 99.70±211.54 U/L; both Phemangioma. TAE may be a useful alternative to surgery for the treatment of hepatic hemangioma. PMID:26287964

  10. Kidney volume correlates with tumor diameter in renal cell carcinoma and is associated with histological poor prognostic features.

    Science.gov (United States)

    Hayes, Brian D; Finn, Stephen P

    2014-02-01

    We aimed to correlate kidney volume (KV) in renal cell carcinoma nephrectomy specimens with tumor diameter (TD), macroscopic growth pattern, and histological features associated with poor prognosis. Histopathology reports, macroscopic specimen photographs, and selected glass slides were retrospectively reviewed. KV was approximated to the volume of an ellipsoid. A total of 273 specimens were identified with median KV 245 cm(3). Kidneys larger than this contained larger tumors (7.5 vs 4.5 cm). KV was significantly greater in tumors of high grade, involving perinephric fat, exhibiting venous invasion, and involving renal sinus. There was a robust linear correlation between KV and TD (r = 0.602) and a weaker correlation between kidney diameter (KD) and TD (r = 0.53). In pT1 tumors, KV (r = 0.40) also correlated better with TD than did KD (r = 0.27). By multiple regression analysis, both TD and venous invasion independently predicted both KD (R (2) = 38.27%) and KV (R (2) = 51.97%). KV and KD correlate well with TD and histopathological features of aggressiveness, although KD correlates better overall and in the pT1 subset.

  11. Extension and validation of the TRANSURANUS burn-up model for helium production in high burn-up LWR fuels

    Science.gov (United States)

    Botazzoli, Pietro; Luzzi, Lelio; Brémier, Stephane; Schubert, Arndt; Van Uffelen, Paul; Walker, Clive T.; Haeck, Wim; Goll, Wolfgang

    2011-12-01

    The TRANSURANUS burn-up model (TUBRNP) calculates the local concentration of the actinides, the main fission products, and 4He as a function of the radial position across a fuel rod. In this paper, the improvements in the helium production model as well as the extensions in the simulation of 238-242Pu, 241Am, 243Am and 242-245Cm isotopes are described. Experimental data used for the extended validation include new EPMA measurements of the local concentrations of Nd and Pu and recent SIMS measurements of the radial distributions of Pu, Am and Cm isotopes, both in a 3.5% enriched commercial PWR UO 2 fuel with a burn-up of 80 and 65 MWd/kgHM, respectively. Good agreement has been found between TUBRNP and the experimental data. The analysis has been complemented by detailed neutron transport calculations (VESTA code), and also revealed the need to update the branching ratio for the 241Am(n,γ) 242mAm reaction in typical PWR conditions.

  12. Synovectomy by Neutron capture; Sinovectomia por captura de neutrones

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H.R.; Torres M, C. [Centro Regional de Estudios Nucleares, Universidad Autonoma de Zacatecas, C. Cipres 10, Fracc. La Penuela, 98000 Zacatecas (Mexico)

    1998-12-31

    The Synovectomy by Neutron capture has as purpose the treatment of the rheumatoid arthritis, illness which at present does not have a definitive curing. This therapy requires a neutron source for irradiating the articulation affected. The energy spectra and the intensity of these neutrons are fundamental since these neutrons induce nuclear reactions of capture with Boron-10 inside the articulation and the freely energy of these reactions is transferred at the productive tissue of synovial liquid, annihilating it. In this work it is presented the neutron spectra results obtained with moderator packings of spherical geometry which contains in its center a Pu{sup 239} Be source. The calculations were realized through Monte Carlo method. The moderators assayed were light water, heavy water base and the both combination of them. The spectra obtained, the average energy, the neutron total number by neutron emitted by source, the thermal neutron percentage and the dose equivalent allow us to suggest that the moderator packing more adequate is what has a light water thickness 0.5 cm (radius 2 cm) and 24.5 cm heavy water (radius 26.5 cm). (Author)

  13. Morphological leaf variability in natural populations of Pistacia atlantica Desf. subsp. atlantica along climatic gradient: new features to update Pistacia atlantica subsp. atlantica key

    Science.gov (United States)

    El Zerey-Belaskri, Asma; Benhassaini, Hachemi

    2016-04-01

    The effect of bioclimate range on the variation in Pistacia atlantica Desf. subsp. atlantica leaf morphology was studied on 16 sites in Northwest Algeria. The study examined biometrically mature leaves totaling 3520 compound leaves. Fifteen characters (10 quantitative and 5 qualitative) were assessed on each leaf. For each quantitative character, the nested analysis of variance (ANOVA) was used to examine relative magnitude of variation at each level of the nested hierarchy. The correlation between the climatic parameters and the leaf morphology was examined. The statistical analysis applied on the quantitative leaf characters showed highly significant variation at the within-site level and between-site variation. The correlation coefficient ( r) showed also an important correlation between climatic parameters and leaf morphology. The results of this study exhibited several values reported for the first time on the species, such as the length and the width of the leaf (reaching up to 24.5 cm/21.9 cm), the number of leaflets (up to 18 leaflets/leaf), and the petiole length of the terminal leaflet (reaching up to 3.4 cm). The original findings of this study are used to update the P. atlantica subsp. atlantica identification key.

  14. Early surgical outcomes of coronary heart disease with severe ischemic mitral regurgitation%冠心病合并重度缺血性二尖瓣关闭不全的外科治疗早期疗效

    Institute of Scientific and Technical Information of China (English)

    麦明杰; 陈星权; 郑少忆; 吴若彬; 郭惠明; 黄劲松

    2011-01-01

    目的 总结对冠心病合并重度缺血性二尖瓣关闭不全外科治疗的经验.方法 自2006年1月~2009年12月,45例冠心病合并重度缺血性二尖瓣关闭不全(ischemic mitral valve regurgitation,IMR珩冠状动脉旁路移植术时同期行二尖瓣成形术24例,瓣膜置换术21例.男35例,女10例;年龄32~74岁[平均(58.46±12.51)岁].结果 围术期死亡2例,死于多器官功能衰竭(multiple organ failure,MOF).超声心动图检查提示:术后二尖瓣反流面积与术前比较明显下降[(11.80±2.45)cm2和(2.83±0.98)cm2,t=22.80,P=0.00],术后左心室舒张期末内径(left ventricular end diastolic diameter,LVEDD) 与术前比较明显减小[(57.61±10.06)mm和(51.84±8.98)mm,t=2.85,P=0.005)].左心室射血分数(left ventricular ejection fraction,LVEF)无明显差异(52.7%±15.4%和53.2%±13.2%,t=0.16,P=0.87).结论 治疗冠心病合并重度缺血性二尖瓣关闭不全,对二尖瓣病变进行必要的外科手术矫正,早期可改善左心室收缩功能,长期预后有待更多的追踪.%Objective To summarize the experience with surgical treatment of coronary artery disease with severe ischemic mitral valve regurgitation (IMR). Methods From January 2006 to December 2009, 45 patients (35 males, 10 females aged 32-74 years) with the diagnosis of coronary artery disease complicated by IMR underwent coronary artery bypass grafting (CABG) combined with mitral valve plasty (MVP, 24 cases) or mitral valve replacement (MVR, 21 cases). Results Perioperative deaths occurred in 2 cases due to multiple organ failure (MOF). Echocardiography showed a significant reduction of the mitral regurgitation area (from 11.80±2.45 cm2 to 2.83±0.98 cm2, t=22.80, P=0.00) after CABG combined with mitral valve surgery, with also significantly reduced postoperative left ventricular end diastolic diameter (LVEDD) (from 57.61±10.06 mm to 51.84±8.98 mm, t=2.85, P=0.005). No significant difference was detected in the left ventricular ejection fraction after the operation [(52.7±15.4)% vs (53.2±13.2)%, t=0.16, P=0.87)]. Conclusion CABG combined with mitral valve surgery can improve early postoperative left ventricular function in patients with ischemic coronary heart disease complicated by severe mitral regurgitation, but further follow-up study is still needed for evaluation of the long-term results.

  15. First direct evidence of chalcolithic footwear from the near eastern highlands.

    Directory of Open Access Journals (Sweden)

    Ron Pinhasi

    Full Text Available In 2008, a well preserved and complete shoe was recovered at the base of a Chalcolithic pit in the cave of Areni-1, Armenia. Here, we discuss the chronology of this find, its archaeological context and its relevance to the study of the evolution of footwear. Two leather samples and one grass sample from the shoe were dated at the Oxford Radiocarbon Accelerator Unit (ORAU. A third leather sample was dated at the University of California-Irvine Accelerator Mass Spectrometry Facility (UCIAMS. The R_Combine function for the three leather samples provides a date range of 3627-3377 Cal BC (95.4% confidence interval and the calibrated range for the straw is contemporaneous (3627-3377 Cal BC. The shoe was stuffed with loose, unfastened grass (Poaceae without clear orientation which was more than likely used to maintain the shape of the shoe and/or prepare it for storage. The shoe is 24.5 cm long (European size 37, 7.6 to 10 cm wide, and was made from a single piece of leather that wrapped around the foot. It was worn and shaped to the wearer's right foot, particularly around the heel and hallux where the highest pressure is exerted in normal gait. The Chalcolithic shoe provides solid evidence for the use of footwear among Old World populations at least since the Chalcolithic. Other 4th millennium discoveries of shoes (Italian and Swiss Alps, and sandals (Southern Israel indicate that more than one type of footwear existed during the 4th millennium BC, and that we should expect to discover more regional variations in the manufacturing and style of shoes where preservation conditions permit.

  16. Transcatheter Arterial Embolization Alone for Giant Hepatic Hemangioma.

    Directory of Open Access Journals (Sweden)

    Jun-Hui Sun

    Full Text Available Giant hepatic hemangioma is a benign liver condition that may be treated using surgery. We studied the digital subtraction angiographic (DSA characteristics of giant hepatic hemangioma, and the effectiveness of transcatheter arterial embolization (TAE alone for its treatment. This was a retrospective study of 27 patients diagnosed with giant hepatic hemangioma and treated with TAE alone (using lipiodol mixed with pingyangmycin at the Division of Hepatobiliary and Pancreatic Surgery, First Affiliated Hospital, Zhejiang University, between January 2010 and March 2013. The feeding arteries were identified using DSA. All patients were followed up for between three weeks and 12 months. Changes in tumor diameter and symptoms were observed. The 27 patients included had giant hepatic hemangiomas ranging from 5.3 to 24.5 cm (mean, 11.24±5.08 cm in the right (n = 13, left (n = 1 or both (n = 13 lobes. Preoperative hepatic angiography showed multiple abnormal vascular lakes in the early phase, known as the "early leaving but late returning, hanging nut on a twig" sign. On the day after TAE, hepatic transaminase levels were increased (ALT: 22.69±17.95 to 94.88±210.32 U/L; ALT: 24.00±12.37 to 99.70±211.54 U/L; both P<0.05, but not total bilirubin. Six patients complained of abdominal pain, and 12 experienced transient fever. In the months after TAE, tumor size decreased (baseline: 11.24±5.08; 3 months: 8.95±4.33; 6 months: 7.60±3.90 cm; P<0.05, and the patients' condition improved. These results indicated that TAE was effective and safe for treating giant hepatic hemangioma. TAE may be a useful alternative to surgery for the treatment of hepatic hemangioma.

  17. [Lattice vibration of Sr3TaGa3Si2O14 single crystal].

    Science.gov (United States)

    Yang, Hong; Lu, Gui-Wu; Yu, Ying-Hui; Li, Ying-Feng; Wang, Zeng-Mei

    2008-03-01

    Based on the space group theory, the normal vibration modes of Sr3 TaGa3Si2O14 (STGS) single crystal were predicted, and the Raman scattering intensities of non-polar and polar modes were calculated. The Raman spectrum of STGS crystal was measured, and lattice vibration modes of STGS crystal were assigned. For symmetry species A1, six typical Raman-active optical modes have been recorded at 126, 245, 557, 604, 896 and 991 cm(-1), respectively. It is easy to assign the mode of 126 cm(-1) as the relative translation between SiO4, Sr and the TaO6. The mode 245 cm(-1) corresponds to the twisting vibration of SiO4 correlating with the Sr-TaO6-Sr stretching vibration. The mode 557 cm(-1) was assigned as the O-Ta-O stretching vibration, while the mode 604 cm(-1) as the O-Ga-O stretching vibration. The band at 896 cm(-1) in the Raman spectrum was assigned to be the O-Si-O stretching vibration of the two SiO4 tetrahedra in the primitive cell of STGS single crystal. Meanwhile, the band at 991 cm(-1) in the Raman spectrum was assigned to be the Si-O stretching vibration of the two SiO4 tetrahedra in the primitive cell of STGS single crystal. The layer structure of STGS crystal was identified by both theory study and Raman spectroscopy experiment results. The small anisotropy and piezoelectric modulus of STGS crystal were ascribed to the weak distortion of decahedral unit.

  18. Application of Geospatial Information System for the Study of Illuminance in Carpet Weaving Workshops in Bokan, Iran

    Directory of Open Access Journals (Sweden)

    Faramarz Madjidi

    2015-12-01

    Full Text Available Background: Carpet weaving is an occupation that requires sufficient and appropriate lighting. The lighting in carpet weaving workshops affects the productivity and the physical and mental health of workers. Therefore, the evaluation of the illumination and the identification of work stations requiring lighting modifications will be helpful in promotion of the health and safety of workers in carpet weaving workshops. Methods: This study was carried out for the evaluation of illumination on the basis of Geospatial Information System (GIS technology in two carpet weaving workshops of Bokan city. As per the norms of Illumination Engineering Society, the sensors of the photometer Testo 545 were placed at lowest and highest of 35 and 163 cm in workshop I, and at 40 and 245 cm in workshop II, which correspond to the lowest and highest work surfaces in the respective workshops. Total, natural, and artificial illuminance was measured in the center of each measurement station using the photometer, and data was analyzed using the Arc GIS software. The maximum and minimum illuminances as well as isolux curves were obtained for each workshop. Results: The illuminance in workshops I and II were found to be lower and higher, respectively, than 200 lux, which is considered the standard for carpet weaving workshops. Thus, improving the artificial lighting system or redesigning it is essential for ensuring that the standard conditions of illuminance (200–300 lux are provided. Discussion: This study showed that the application of GIS technology renders the assessment of illumination in carpet weaving workshops possible. This assessment method could also prove useful for determining the exact stations in the carpet weaving workshops that need modifications, thereby leading to cost reduction.

  19. Highly enriched isotope samples of uranium and transuranium elements for scientific investigation

    Science.gov (United States)

    Vesnovskii, Stanislav P.; Polynov, Vladimir N.; Danilin, Lev. D.

    1992-02-01

    The paper describes the production of highly enriched isotopes of uranium, plutonium, americium and curium by electromagnetic separation for scientific and applied researches in physics, chemistry, geology, medicine, biology and other fields. Using the equipment described, the isotopes are produced in quantities sufficient to set up nuclear physical experiments, to produce nuclear reference materials and standard sources for calibration of radiometrical and mass spectrometrical equipment, in radionuclide metrology, etc. For the following isotopes the indicated degrees of isotopic enrichment were achieved: 233U - 99.97%; 235U - 99.97%; 236U - 98.0%; 238U - 99.997%; 238Pu - 99.6%; 239Pu - 99.9977%; 240Pu - 99.9-100%; 241Pu - 96.998%; 242Pu - 97.8-99.96%; 244Pu - 96.7%; 241Am - 99.6%; 242Am - 73.6%; 243Am - 99.2-99.94%; 243Cm - 99.99%; 245Cm - 99.998%; 246Cm - 99.8%; 247Cm - 90%; 248Cm - 97%. Methods for preparing layers of highly enriched isotopes on various substances are presented: - electrochemical deposition of transuranic elements from aqueous-organic and organic media and vacuum spraying: - the method of foil and coating formation via compounds in the vapour phase; - the method of fabrication of layers of transuranic elements on superthin (1-2 μm) metal substrates with additional isolating polymer-metal coatings (0.2-0.4 μm), that substantially decrease material transfer from the active layer and increase safety of product handling.

  20. On-board hydrogen generation for transport applications: the HotSpot™ methanol processor

    Science.gov (United States)

    Edwards, Neil; Ellis, Suzanne R.; Frost, Jonathan C.; Golunski, Stanislaw E.; van Keulen, Arjan N. J.; Lindewald, Nicklas G.; Reinkingh, Jessica G.

    In the absence of a hydrogen infrastructure, development of effective on-board fuel processors is likely to be critical to the commercialisation of fuel-cell cars. The HotSpot™ reactor converts methanol, water and air in a single compact catalyst bed into a reformate containing mainly CO2 and hydrogen (and unreacted nitrogen). The process occurs by a combination of exothermic partial oxidation and endothermic steam reforming of methanol, to produce 750 l of hydrogen per hour from a 245-cm3 reactor. The relative contribution of each reaction can be tuned to match the system requirements at a given time. Scale-up is achieved by the parallel combination of the required number of individual HotSpot reactors, which are fed from a central manifold. Using this modular design, the start-up and transient characteristics of a large fuel-processor are identical to that of a single reactor. When vaporised liquid feed and air are introduced into cold reactors, 100% output is achieved in 50 s; subsequent changes in throughput result in instantaneous changes in output. Surplus energy within the fuel-cell powertrain can be directed to the manifold, where it can be used to vaporise the liquid feeds and so promote steam reforming, resulting in high system efficiency. The small amount of CO that is produced by the HotSpot reactions is attenuated to <10 ppm by a catalytic clean-up unit. The HotSpot concept and CO clean-up strategy are not limited to the processing of methanol, but are being applied to other organic fuels.

  1. Effect of ZnCl{sub 2} activation on CO{sub 2} adsorption of N-doped nanoporous carbons from polypyrrole

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Long-Yue [Department of Chemical Engineering, Yanbian University, Yanji 133002 (China); Department of Chemistry, Inha University, 253 Nam-gu, Incheon 402-751 (Korea, Republic of); Park, Soo-Jin, E-mail: sjpark@inha.ac.kr [Department of Chemistry, Inha University, 253 Nam-gu, Incheon 402-751 (Korea, Republic of)

    2014-10-15

    In this study, N-doping nanoporous carbons (NNCs) were prepared from polypyrrole (PPY) by ZnCl{sub 2} activation. The activation process was carried out under set conditions (PPY/ZnCl{sub 2}=1/4) at 300–800 °C for 2 h. With increasing activation temperature, the specific surface area and total pore volume of the NNCs increased significantly from 539 m{sup 2}/g (300 °C) to 1268 m{sup 2}/g (700 °C) and from 0.245 cm{sup 3}/g (300 °C) to 0.561 cm{sup 3}/g (700 °C), respectively. In addition, the use of PPY carbon precursors allowed the integration of high N content (9.28 wt%) and resulted in a large narrow micropore distribution (<1 nm) in the prepared NNCs. The CO{sub 2} adsorption isotherms showed that PZ-600 exhibited the best CO{sub 2} adsorption capacity of 167 mg/g at 1 bar and 25 °C when the activation temperature was 600 °C. - Graphical abstract: CO{sub 2}/298 K adsorption/desorption isotherms of the N-enriched porous carbons. - Highlights: • N-doping nanoporous carbons were prepared from polypyrrole by ZnCl{sub 2} activation. • Through ZnCl{sub 2} activation, the specific surface area and total pore volume increased. • PZ-600 exhibited the best CO{sub 2} adsorption capacity of 167 mg/g at 1 bar and 25 °C.

  2. OSMOSE program : statistical review of oscillation measurements in the MINERVE reactor R1-UO2 configuration.

    Energy Technology Data Exchange (ETDEWEB)

    Stoven, G.; Klann, R.; Zhong, Z.; Nuclear Engineering Division

    2007-08-28

    The OSMOSE program is a collaboration on reactor physics experiments between the United States Department of Energy and the France Commissariat Energie Atomique. At the working level, it is a collaborative effort between the Argonne National Laboratory and the CEA Cadarache Research Center. The objective of this program is to measure very accurate integral reaction rates in representative spectra for the actinides important to future nuclear system designs, and to provide the experimental data for improving the basic nuclear data files. The main outcome of the OSMOSE measurement program will be an experimental database of reactivity-worth measurements in different neutron spectra for the heavy nuclides. This database can then be used as a benchmark to verify and validate reactor analysis codes. The OSMOSE program (Oscillation in Minerve of isotopes in Eupraxic Spectra) aims at improving neutronic predictions of advanced nuclear fuels through oscillation measurements in the MINERVE facility on samples containing the following separated actinides: {sup 232}Th, {sup 233}U, {sup 234}U, {sup 235}U, {sup 236}U, {sup 238}U, {sup 237}Np, {sup 238}Pu, {sup 239}Pu, {sup 240}Pu, {sup 241}Pu, {sup 242}Pu, {sup 241}Am, {sup 243}Am, {sup 244}Cm, and {sup 245}Cm. The first part of this report provides an overview of the experimental protocol and the typical processing of a series of experimental results which is currently performed at CEA-Cadarache. In the second part of the report, improvements to this technique are presented, as well as the program that was created to process oscillation measurement results from the MINERVE facility in the future.

  3. Validation of minor actinides fission neutron cross-sections

    Directory of Open Access Journals (Sweden)

    Pešić Milan P.

    2015-01-01

    Full Text Available Verification of neutron fission cross-sections of minor actinides from some recently available evaluated nuclear data libraries was carried out by comparison of the reaction rates calculated by the MCNP6.1 computer code to the experimental values. The experimental samples, containing thin layers of 235U, 237Np, 238,239,240,241Pu, 242mAm, 243Cm, 245Cm, and 247Cm, deposited on metal support and foils of 235U (pseudo-alloy 27Al + 235U, 238U, natIn, 64Zn, 27Al, and multi-component sample alloy 27Al + 55Mn + natCu + natLu + 197Au, were irradiated in the channels of the tank containing fluorine salts 0.52NaF + 0.48ZrF4, labelled as the Micromodel Salt Blanket, inserted in the lattice centre of the MAKET heavy water critical assembly at the Institute for Theoretical and Experimental Physics, Moscow. This paper is a continuation of earlier initiated scientific-research activities carried out for validation of the evaluated fission cross-sections of actinides that were supposed to be used for the quality examination of the fuel design of the accelerator driven systems or fast reactors, and consequently, determination of transmutation rates of actinides, and therefore, determination of operation parameters of these reactor facilities. These scientific-research activities were carried out within a frame of scientific projects supported by the International Science and Technology Center and the International Atomic Energy Agency co-ordinated research activities, from 1999 to 2010. Obtained results confirm that further research is needed in evaluations in order to establish better neutron cross-section data for the minor actinides and selected nuclides which could be used in the accelerator driven systems or fast reactors.

  4. MRI at the completion of chemoradiotherapy can accurately evaluate the extent of disease in women with advanced urethral carcinoma undergoing anterior pelvic exenteration

    Energy Technology Data Exchange (ETDEWEB)

    Gourtsoyianni, S.; Hudolin, T. [Department of Radiology, Memorial Sloan-Kettering Cancer Centre, 1275 York Avenue, New York, NY (United States); Sala, E. [Department of Radiology, Box 218, Addenbrooke' s Hospital, Hills Road, Cambridge (United Kingdom); Goldman, D. [Department of Radiology, Memorial Sloan-Kettering Cancer Centre, 1275 York Avenue, New York, NY (United States); Bochner, B.H. [Department of Urology, Memorial Sloan-Kettering Cancer Centre, 1275 York Avenue, New York, NY (United States); Hricak, Hedvig, E-mail: muellnea@mskcc.org [Department of Radiology, Memorial Sloan-Kettering Cancer Centre, 1275 York Avenue, New York, NY (United States)

    2011-11-15

    Aim: To demonstrate the value of pelvic magnetic resonance imaging (MRI) in mapping tumour extension after chemoradiotherapy and before anterior pelvic exenteration in patients with primary carcinoma of the urethra. Materials and methods: The Institutional Review Board approved and issued a waiver of informed consent for this retrospective study, which was compliant with the Health Insurance Portability and Accountability Act. Six women (median age 51 years, range 39-63 years) with histopathology-proven urethral carcinoma who underwent neoadjuvant chemoradiotherapy before anterior pelvic exenteration were included in the study. All had MRI performed at first presentation and after completion of chemoradiotherapy. MRI images were analysed by an experienced reader, who was blinded to the clinical data. The tumour location, signal intensity, size, local extension, and presence of enlarged lymph nodes were recorded for each patient at baseline and after chemoradiotherapy. Surgical histopathology constituted the reference standard. Results: All tumours were locally advanced (stage T3) at baseline MRI. The mean maximum diameter of the tumour at baseline MRI was 3.7 cm (range 2.4-5 cm). After chemoradiotherapy, the mean reduction in maximum tumour diameter on MRI was 44% (range 13-67%), but only three cases were down-staged. MRI was accurate in the evaluation of tumour extension after completion of chemoradiotherapy in all cases. Persistence of bladder neck and anterior vaginal wall invasion was correctly identified in three cases. Conclusion: In women with advanced primary urethral cancer, MRI is an excellent tool for monitoring neo-adjuvant chemoradiotherapy changes and evaluating the extent of disease before exenterative surgery.

  5. Capillary electrophoresis of heparin and other glycosaminoglycans using a polyamine running electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Loegel, Thomas N.; Trombley, John D.; Taylor, Richard T. [Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056 (United States); Danielson, Neil D., E-mail: danielnd@muohio.edu [Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056 (United States)

    2012-11-13

    Highlights: Black-Right-Pointing-Pointer Ethylenediamine is likely acting as an ion-pairing agent. Black-Right-Pointing-Pointer Oversulfated chondroitin sulfate is last peak instead of first peak. Black-Right-Pointing-Pointer There is about a factor of five improved detectability with a 12.5 min analysis time. Black-Right-Pointing-Pointer Use of a 50 {mu}m ID capillary is possible. - Abstract: This study involves the use of polyamines as potential resolving agents for the capillary electrophoresis (CE) of glycosaminoglycans (GAGs), specifically heparin, dermatan sulfate, chondroitin sulfate, over-sulfated chondroitin sulfate (OSCS), and hyaluronan. All of the compounds can be separated from each other with the exception of chondroitin sulfate and hyaluronan. Using optimization software, the final run conditions are found to be 200 mM ethylenediamine and 45.5 mM phosphate as the electrolyte with -14 V applied across a 50 {mu}m ID Multiplication-Sign 24.5 cm fused silica capillary at 15 Degree-Sign C. The ion migration order, with OSCS as the last instead of the first peak, is in contrast to previous reports using either a high molarity TRIS or lithium phosphate run buffer with narrower bore capillaries. Total analysis time is 12. 5 min and the relative standard deviation of the heparin migration time is about 2.5% (n = 5). The interaction mechanism between selected polyamines and heparin is explored using conductivity measurements in addition to CE experiments to show that an ion-pairing mechanism is likely.

  6. Generic Selection Criteria for Safety and Patient Benefit [IV] - Physicochemical and pharmaceutical properties of brand-name and generic ketoprofen tapes.

    Science.gov (United States)

    Wada, Yuko; Kihara, Maki; Nozawa, Mitsuru; Shimokawa, Ken-Ichi; Ishii, Fumiyoshi

    2015-06-01

    The physicochemical and pharmaceutical properties (pH, peel force, water-vapor permeability, and stretchability) of brand-name and generic ketoprofen products were evaluated and compared. The pHs of Mohrus as a brand-name product and Teikoku as a generic product were low (about 4). Among the other generic products, Patell and Nichi-Iko had a pH of about 4.3 while Frestol, Raynanon, BMD, and Touchron showed a pH of 4.6-5.2, which was in the pH range of normal healthy skin (4.5-6.5). The adhesive force was high (≥ 1.38) for Mohrus as a brand-name product as well as for Teikoku and Patell as generic products, but it was low (≤ 0.57) for the other 5 generic products. The water-vapor permeabilities of Mohrus as a brand-name product and Teikoku and Patell as generic products were low, being less than 1/6 of those for the other 5 generic products. Among the 5 generic products, BMD showed the highest water-vapor permeability (1,330 g/m²), and the other products also showed a value ≥ 1,100 g/m². The elongatedness of Mohrus was the lowest (15.5 cm), and that of Raynanon was the highest (24.5 cm); the difference was 9 cm. In this study, the physiochemical and pharmaceutical properties of ketoprofen tapes were clarified, which will allow pharmacists to provide products according to the needs of each patient when a brand-name product is changed to a generic one.

  7. Ennis Nursing Home, Showgrounds Road, Drumbiggle, Ennis, Clare.

    LENUS (Irish Health Repository)

    Pinhasi, Ron

    2010-01-01

    In 2008, a well preserved and complete shoe was recovered at the base of a Chalcolithic pit in the cave of Areni-1, Armenia. Here, we discuss the chronology of this find, its archaeological context and its relevance to the study of the evolution of footwear. Two leather samples and one grass sample from the shoe were dated at the Oxford Radiocarbon Accelerator Unit (ORAU). A third leather sample was dated at the University of California-Irvine Accelerator Mass Spectrometry Facility (UCIAMS). The R_Combine function for the three leather samples provides a date range of 3627-3377 Cal BC (95.4% confidence interval) and the calibrated range for the straw is contemporaneous (3627-3377 Cal BC). The shoe was stuffed with loose, unfastened grass (Poaceae) without clear orientation which was more than likely used to maintain the shape of the shoe and\\/or prepare it for storage. The shoe is 24.5 cm long (European size 37), 7.6 to 10 cm wide, and was made from a single piece of leather that wrapped around the foot. It was worn and shaped to the wearer\\'s right foot, particularly around the heel and hallux where the highest pressure is exerted in normal gait. The Chalcolithic shoe provides solid evidence for the use of footwear among Old World populations at least since the Chalcolithic. Other 4th millennium discoveries of shoes (Italian and Swiss Alps), and sandals (Southern Israel) indicate that more than one type of footwear existed during the 4th millennium BC, and that we should expect to discover more regional variations in the manufacturing and style of shoes where preservation conditions permit.

  8. Study of calculated and measured time dependent delayed neutron yields. [TX, for calculating delayed neutron yields; MATINV, for matrix inversion; in FORTRAN for LSI-II minicomputer

    Energy Technology Data Exchange (ETDEWEB)

    Waldo, R.W.

    1980-05-01

    Time-dependent delayed neutron emission is of interest in reactor design, reactor dynamics, and nuclear physics studies. The delayed neutrons from neutron-induced fission of /sup 232/U, /sup 237/Np, /sup 238/Pu, /sup 241/Am, /sup 242m/Am, /sup 245/Cm, and /sup 249/Cf were studied for the first time. The delayed neutron emission from /sup 232/Th, /sup 233/U, /sup 235/U, /sup 238/U, /sup 239/Pu, /sup 241/Pu, and /sup 242/Pu were measured as well. The data were used to develop an empirical expression for the total delayed neutron yield. The expression gives accurate results for a large variety of nuclides from /sup 232/Th to /sup 252/Cf. The data measuring the decay of delayed neutrons with time were used to derive another empirical expression predicting the delayed neutron emission with time. It was found that nuclides with similar mass-to-charge ratios have similar decay patterns. Thus the relative decay pattern of one nuclide can be established by any measured nuclide with a similar mass-to-charge ratio. A simple fission product yield model was developed and applied to delayed neutron precursors. It accurately predicts observed yield and decay characteristics. In conclusion, it is possible to not only estimate the total delayed neutron yield for a given nuclide but the time-dependent nature of the delayed neutrons as well. Reactors utilizing recycled fuel or burning actinides are likely to have inventories of fissioning nuclides that have not been studied until now. The delayed neutrons from these nuclides can now be incorporated so that their influence on the stability and control of reactors can be delineated. 8 figures, 39 tables.

  9. First direct evidence of chalcolithic footwear from the near eastern highlands.

    LENUS (Irish Health Repository)

    Pinhasi, Ron

    2010-01-01

    In 2008, a well preserved and complete shoe was recovered at the base of a Chalcolithic pit in the cave of Areni-1, Armenia. Here, we discuss the chronology of this find, its archaeological context and its relevance to the study of the evolution of footwear. Two leather samples and one grass sample from the shoe were dated at the Oxford Radiocarbon Accelerator Unit (ORAU). A third leather sample was dated at the University of California-Irvine Accelerator Mass Spectrometry Facility (UCIAMS). The R_Combine function for the three leather samples provides a date range of 3627-3377 Cal BC (95.4% confidence interval) and the calibrated range for the straw is contemporaneous (3627-3377 Cal BC). The shoe was stuffed with loose, unfastened grass (Poaceae) without clear orientation which was more than likely used to maintain the shape of the shoe and\\/or prepare it for storage. The shoe is 24.5 cm long (European size 37), 7.6 to 10 cm wide, and was made from a single piece of leather that wrapped around the foot. It was worn and shaped to the wearer\\'s right foot, particularly around the heel and hallux where the highest pressure is exerted in normal gait. The Chalcolithic shoe provides solid evidence for the use of footwear among Old World populations at least since the Chalcolithic. Other 4th millennium discoveries of shoes (Italian and Swiss Alps), and sandals (Southern Israel) indicate that more than one type of footwear existed during the 4th millennium BC, and that we should expect to discover more regional variations in the manufacturing and style of shoes where preservation conditions permit.

  10. PRELIMINARY CROSS SECTION AND NU-BAR COVARIANCES FOR WPEC SUBGROUP 26

    Energy Technology Data Exchange (ETDEWEB)

    ROCHMAN,D.

    2007-01-31

    We report preliminary cross section covariances developed for the WPEC Subgroup 26 for 45 out of 52 requested materials. The covariances were produced in 15- and 187-group representations as follows: (1) 36 isotopes ({sup 16}O, {sup 19}F, {sup 23}Na, {sup 27}Al, {sup 28}Si, {sup 52}Cr, {sup 56,56}Fe, {sup 58}Ni, {sup 90,91,92,94}Zr, {sup 166,167,168,170}Er, {sup 206,207,208}Pb, {sup 209}Bi, {sup 233,234,236}U, {sup 237}Np, {sup 238,240,241,242}Pu, {sup 241,242m,243}Am, {sup 242,243,244,245}Cm) were evaluated using the BNL-LANL methodology. For the thermal region and the resolved and unresolved resonance regions, the methodology has been based on the Atlas-Kalman approach, in the fast neutron region the Empire-Kalman method has been used; (2) 6 isotopes ({sup 155,156,157,158,160}Gd and {sup 232}Th) were taken from ENDF/B-VII.0; and (3) 3 isotopes ({sup 1}H, {sup 238}U and {sup 239}Pu) were taken from JENDL-3.3. For 6 light nuclei ({sup 4}He, {sup 6,7}Li, {sup 9}Be, {sup 10}B, {sup 12}C), only partial cross section covariance results were obtained, additional work is needed and they do not report the results here. Likewise, the cross section covariances for {sup 235}U, which they recommend to take from JENDL-3.3, will be included once the multigroup processing is successfully completed. Covariances for the average number of neutrons per fission, total {nu}-bar, are provided for 10 actinides identified as priority by SG26. Further work is needed to resolve some of the issues and to produce covariances for the full set of 52 materials.

  11. Phytoremediation: role of terrestrial plants and aquatic macrophytes in the remediation of radionuclides and heavy metal contaminated soil and water.

    Science.gov (United States)

    Sharma, Sunita; Singh, Bikram; Manchanda, V K

    2015-01-01

    Nuclear power reactors are operating in 31 countries around the world. Along with reactor operations, activities like mining, fuel fabrication, fuel reprocessing and military operations are the major contributors to the nuclear waste. The presence of a large number of fission products along with multiple oxidation state long-lived radionuclides such as neptunium ((237)Np), plutonium ((239)Pu), americium ((241/243)Am) and curium ((245)Cm) make the waste streams a potential radiological threat to the environment. Commonly high concentrations of cesium ((137)Cs) and strontium ((90)Sr) are found in a nuclear waste. These radionuclides are capable enough to produce potential health threat due to their long half-lives and effortless translocation into the human body. Besides the radionuclides, heavy metal contamination is also a serious issue. Heavy metals occur naturally in the earth crust and in low concentration, are also essential for the metabolism of living beings. Bioaccumulation of these heavy metals causes hazardous effects. These pollutants enter the human body directly via contaminated drinking water or through the food chain. This issue has drawn the attention of scientists throughout the world to device eco-friendly treatments to remediate the soil and water resources. Various physical and chemical treatments are being applied to clean the waste, but these techniques are quite expensive, complicated and comprise various side effects. One of the promising techniques, which has been pursued vigorously to overcome these demerits, is phytoremediation. The process is very effective, eco-friendly, easy and affordable. This technique utilizes the plants and its associated microbes to decontaminate the low and moderately contaminated sites efficiently. Many plant species are successfully used for remediation of contaminated soil and water systems. Remediation of these systems turns into a serious problem due to various anthropogenic activities that have

  12. Changes in central retinal artery blood flow after ocular warming and cooling in healthy subjects

    Directory of Open Access Journals (Sweden)

    Shamshad M

    2010-01-01

    Full Text Available Context: Retinal perfusion variability impacts ocular disease and physiology. Aim: To evaluate the response of central retinal artery (CRA blood flow to temperature alterations in 20 healthy volunteers. Setting and Design: Non-interventional experimental human study. Materials and Methods: Baseline data recorded: Ocular surface temperature (OST in °C (thermo-anemometer, CRA peak systolic velocity (PSV and end diastolic velocity (EDV in cm/s using Color Doppler. Ocular laterality and temperature alteration (warming by electric lamp/cooling by ice-gel pack were randomly assigned. Primary outcomes recorded were: OST and intraocular pressure (IOP immediately after warming or cooling and ten minutes later; CRA-PSV and EDV at three, six and nine minutes warming or cooling. Statistical Analysis: Repeated measures ANOVA. Results: (n = 20; μ±SD: Pre-warming values were; OST: 34.5±1.02°C, CRA-PSV: 9.3±2.33cm/s, CRA-EDV: 4.6±1.27cm/s. OST significantly increased by 1.96°C (95% CI: 1.54 to 2.37 after warming, but returned to baseline ten minutes later. Only at three minutes, the PSV significantly rose by 1.21cm/s (95% CI: 0.51to1.91. Pre-cooling values were: OST: 34.5±0.96°C, CRA-PSV: 9.7±2.45 cm/s, CRA-EDV: 4.7±1.12cm/s. OST significantly decreased by 2.81°C (95% CI: -2.30 to -3.37 after cooling, and returned to baseline at ten minutes. There was a significant drop in CRA-PSV by 1.10cm/s (95% CI: -2.05 to -0.15 and CRA-EDV by 0.81 (95% CI: -1.47 to -0.14 at three minutes. At six minutes both PSV (95% CI: -1.38 to -0.03 and EDV (95% CI: -1.26 to -0.02 were significantly lower. All values at ten minutes were comparable to baseline. The IOP showed insignificant alteration on warming (95% CI of difference: -0.17 to 1.57mmHg, but was significantly lower after cooling (95% CI: -2.95 to -4.30mmHg. After ten minutes, IOP had returned to baseline. Conclusion : This study confirms that CRA flow significantly increases on warming and decreases on cooling, the latter despite a significant lowering of IOP.

  13. Growth Characteristics and Growth Strain of Eucalyptus dunnii%邓恩桉生长特性与生长应变研究

    Institute of Scientific and Technical Information of China (English)

    叶露; J.Doland Nichols; Carolyn A.Raymond; Kevin Glencross

    2013-01-01

    [目的]通过研究邓恩桉的生长特性和生长应变,为邓恩桉木材利用提供科学数据.[方法]以9.5年生人工林邓恩桉为研究对象,测定和评估树高(Ht)、胸径(DBH)、胸高比(DBH/Ht)、生长应变,并分析生长应变与生长性状的相关性.[结果]邓恩桉树高、胸径和生长应变的小区间差异显著.胸径和生长应变的变化幅度分别为10.2~ 24.5 cm,-0.227 ~-0.0M mm.生长应变水平在上坡方向显著高于下坡方向.邓恩桉生长应变与树高、胸径、胸高比无显著相关性.[结论]邓恩桉可作为速生材培育,邓恩桉木材的生长应力不受生长性状的影响.实现高生长和选择低应力水平的速生邓恩桉作为实木加工是可行的.%The aim was to provide the scientific data for utilization of E.dunnii wood through investigating its growth and growth strain.[Method] With 9.5-year-old E.dunnii plantation as study object,tree height (Ht),diameter at breast height (DBH),ratio of diameter to tree height (DBH/Ht),growth strain and their correlations were estimated and analyzed.[Result] There were significant differences in Ht,DBH and growth strain between plots.DBH and growth strain were in the range of 10.2-24.5 cm,-0.227--0.064 mm,respectively.Uphill growth strain was significantly greater than the downhill growth strain.Growth strain had no significant correlations with Ht,DBH or DBH/Ht ratio in E.dunnii.[Conclusion] E.dunnii was a potentially fast-growing species.It was feasible to obtain fast-growing E.dunnii trees with low level of growth strain as the strain was not affected by its growth.

  14. Doppler and Elastography as complementary diagnostic methods for mammary neoplasms in female cats

    Directory of Open Access Journals (Sweden)

    M.A.R. Feliciano

    2015-06-01

    Full Text Available Objetivou-se descrever a utilização das técnicas Doppler e elastografia ARFI (acoustic radiation force impulse na avaliação de neoplasias mamárias de gatas, métodos ainda não utilizados para tal estudo em fêmeas felinas. Após a avaliação física e específica das neoplasias mamárias de duas gatas, foram realizadas as avaliações ultrassonográfica modo-B (ecogenicidade, ecotextura e margeamento, Doppler colorido (característica do fluxo sanguíneo e espectral (velocidade sistólica/VS; diastólica/VD; e índice de resistência/IR e a eslatografia ARFI qualitativa (escala de cores e quantitativa (velocidade de cisalhamento dos nódulos mamários, avaliando a aplicabilidade destas técnicas para determinar a malignidade dos tumores mamários. Após mastectomia e histopatologia foram diagnosticados: caso 1: carcinoma tubular; e caso 2: carcinoma mamário cribiforme. As características do modo-B foram similares para ambos os casos (heterogeneidade e margens regulares e não invasivas. Ao Doppler verificou-se presença de neovascularização e valores considerados elevados para os índices vasculares (quando comparado com tecidos benignos de outras espécies, como por exemplo caninos (caso 1 - VS: 23,1cm/s, VD: 8,5cm/s e IR: 0,63; caso 2 - VS: 47,4 e 24,5cm/s; VD: 16,1 e 6,1cm/s e IR: 0,66 e 0,75; assim como os valores da velocidade de cisalhamento dos tecidos (caso 1: 4,07 m/s; caso 2: 4,54 e 6,85 m/s na elastografia quantitativa; sendo que na avaliação qualitativa observou-se predominante rigidez e não deformidade tecidual, características que podem indicar a malignidade tecidual. Conclui-se que estas técnicas podem auxiliar no estudo de neoplasias mamárias em felinos, sugerindo a implementação destas técnicas de imagem para estudos de tumores mamários em felinos.

  15. Morphological and mechanical analysis of electrospun shape memory polymer fibers

    Energy Technology Data Exchange (ETDEWEB)

    Budun, Sinem [Institute of Pure and Applied Science, Marmara University, 34722 Istanbul (Turkey); İşgören, Erkan [Textile Technology, Technical Education Faculty, Marmara University, 34722 Istanbul (Turkey); Erdem, Ramazan, E-mail: ramazanerdem@akdeniz.edu.tr [Textile Technologies, Serik G-S. Sural Vocational School of Higher Education, Akdeniz University, 07500 Antalya (Turkey); Yüksek, Metin [Textile Engineering, Technology Faculty, Marmara University, 34722 Istanbul (Turkey)

    2016-09-01

    Highlights: • Fiber morphology of PU based shape memory fibers varied especially with polymer concentration and applied voltage. • The smallest diameter (381 ± 165 nm) and almost uniform (without bead) fibers were belonged to the sample Y10K30 with a feeding rate of 1 ml/h and an applied voltage of 30 kV at 24.5 cm distance. • All calculated shape fixity results were above 80% and the best value (92 ± 4%) was obtained for Y10K30. • All gained shape recovery results were determined above 100% and the highest measurement (130 ± 4%) was belonged to Y15K39. • The greatest tensile property was obtained for Y10K30 (14.7 ± 3.2 MPa) in machine direction and for Y10K39 (12.9 ± 0.8 MPa) in transverse direction. Y15K39 (411 ± 24%) and Y20K30 (402 ± 34%) possessed the highest elongation results compared with the other electrospun webs. - Abstract: Shape memory block co-polymer Polyurethane (PU) fibers were fabricated by electrospinning technique. Four different solution concentrations (5 wt.%, 10 wt.%, 15 wt.% and 20 wt.%) were prepared by using Tetrahydrofuran (THF)/N,N-dimethylformamide (DMF) (50:50, v/v) as solvents, and three different voltages (30 kV, 35 kV and 38.9 kV) were determined for the electrospinning process. Solution properties were explored in terms of viscosity and electrical conductivity. It was observed that as the polymer concentration increased in the solution, the conductivity declined. Morphological characteristics of the obtained fibers were analyzed through Scanning Electron Microscopy (SEM) measurements. Findings indicated that fiber morphology varied especially with polymer concentration and applied voltage. Obtained fiber diameter ranged from 112 ± 34 nm to 2046 ± 654 nm, respectively. DSC analysis presented that chain orientation of the polymer increased after electrospinning process. Shape fixity and shape recovery calculations were realized. The best shape fixity value (92 ± 4%) was obtained for Y10K30 and the highest shape recovery measurement (130 ± 4%) was belonged to Y15K39. Mechanical properties of the electrospun webs were also investigated in both machine and transverse directions. Tensile and elongation values were also affected from fiber diameter distribution and morphological characteristics of the electrospun webs.

  16. Effects of lanthanoid cations on the first electronic transition of liquid water studied using attenuated total reflection far-ultraviolet spectroscopy: ligand field splitting of lanthanoid hydrates in aqueous solutions.

    Science.gov (United States)

    Goto, Takeyoshi; Ikehata, Akifumi; Morisawa, Yusuke; Higashi, Noboru; Ozaki, Yukihiro

    2012-10-15

    The effects of the lanthanoid cations (Ln(3+)) on the first electronic transition (à ← X̃) of liquid water were studied from the attenuated total reflection far-ultraviolet (ATR-FUV) spectra of trivalent Ln(3+) electrolyte solutions (1 M), except Pm(3+). The à ← X̃ transition energies of the Ln(3+) electrolyte solutions show a distinct tetrad in their dependence on the number of 4f electrons of the Ln(3+) cations. For the half occupation period of the 4f electrons, the à ← X̃ transition energies decrease from La(3+) (4f(0), 8.0375 eV) to Nd(3+) (4f(3), 8.0277 eV) and increase from Sm(3+) (4f(5), 8.0279 eV) to Gd(3+) (4f(7), 8.0374 eV). For the complete occupation period, there are two local minima at Dy(3+) (4f(9), 8.0349 eV) and Yb(3+) (4f(13), 8.0355 eV). The à ← X̃ transition energies of the tetrad nodes (La(3+), Gd(3+), Ho(3+) (4f(10)), and Lu(3+) (4f(14))) increase slightly, as the nuclear charge increases in accordance with the hydration energies of the Ln(3+) cations. The energy difference (ΔE) between the à ← X̃ transition energies and the line between La(3+) and Lu(3+) is largest at Nd(3+) (80.5 cm(-1)) for the half occupation period and at Dy(3+) (26.1 cm(-1)) and Yb(3+) (24.5 cm(-1)) for the complete occupation period. The order of magnitude of ΔE is comparable to the ligand field splitting (LFS) of the ground state multiplets of Ln(3+) complexes. The observed tetrad trend of the à ← X̃ transition energies of the Ln(3+) electrolyte solutions across the 4f period reflects the hydration energies of the Ln(3+) cations and the LFS induced by water ligands.

  17. Actividad antimicrobiana de Weissella confusa y sus metabolitos frente a Escherichia coli y Klebsiella pneumoniae

    Directory of Open Access Journals (Sweden)

    Liliana Serna Cock

    2013-12-01

    Full Text Available Título en ingles: Antimicrobial activity of Weissella confuse and its metabolites against Escherichia coli and  Klebsiella pneumoniaeResumen: Con el fin evaluar el campo de aplicación potencial de una bacteria ácido láctica y de sus metabolitos, se realizó la cinética de la actividad antimicrobiana de W. confusa y de sus  metabolitos contra E. coli, y K. pneumoniae, dos patógenos causantes de enfermedades transmitidas por alimentos. La producción de W. confusa se realizó por fermentación discontinua en sustrato comercial MRS. Se realizaron tres fermentaciones durante 6 horas, sin aireación, agitación continúa 33°C y 100 rpm. Cada hora de fermentación se separaron tres sustancias biológicas, W. confusa con sus metabolitos (W+W10b, células de W. confusa libres de metabolitos (W y metabolito (W10b y se midió la actividad antimicrobiana contra los patógenos E. coli, y K. pneumoniae. Se encontraron diferencias estadísticas significativas entre tratamientos y tiempo de fermentación. Para E. coli el tratamiento W presentó la mayor actividad antimicrobiana, la cual se obtuvo entre la cuarta y sexta hora de fermentación (2.45 cm de diámetro promedio de inhibición. Para K. pneumoniae, los tratamientos W y W+W10b presentaron actividad antimicrobiana entre la cuarta y quinta hora de fermentación, sin diferencia significativa entre ellos. W. confusa y el metabolito W10b demostraron poseer capacidad antimicrobiana contra E. coli y K. pneumoniae, lo cual sugiere que W. confusa y W10b podrían utilizarse como alternativa de bioconservación o bioprotección de alimentos frescos y procesados, para alimentación humana y animal; y podría convertirse en una alternativa al uso de antibióticos para enfermedades causadas por E. coli y K. pneumoniae.Palabras clave: bioconservación, alimentos, enfermedades, aplicaciones biotecnológicas.Summary: The kinetic of antimicrobial activity ofWeissella confusa and their metabolites against E. coli, and K. pneumoniae, (two pathogens causing foodborne illness was evaluated, in order to know the possible use in food processing. W. confusa was produced by batch fermentation using MRS commercial substrate. Three fermentations, of 6 hours at 33 ° C, without aeration, stirring continuously (100 rpm were performed. In every hour of fermentation, three biological substances, W. confusa with their metabolites (W + W10b, W. confusa free cells metabolites (W, and metabolite (W10b were separated, and subsequently the antimicrobial activity against pathogenic E. coli and K. pneumoniae was measured. Statistically significant differences between treatments and fermentation time were found. Treatment (W against E. coli, showed the greatest antimicrobial activity, it was obtained between the fourth and the sixth hours of fermentation (2.45 cm inhibition diameter average. In treatments W and W + W10b against K. pneumoniae, statistically significant differences between them were not found. The antimicrobial activity was shown between the fourth and fifth hour of fermentation. W. confusa and W10b have antimicrobial activity against E. coli andK. pneumoniae, suggesting that W and W10b could be used as an alternative to biopreservation or bioprotection of fresh and processed food for human and animal consumption, and could become an alternative to antibiotics used for diseases caused by E. coli and K. pneumoniae.Key words: bioconservation, food, diseases, biotechnology applications.

  18. Validation of live animal ultrasonic measurements of body composition in market lambs.

    Science.gov (United States)

    Emenheiser, J C; Greiner, S P; Lewis, R M; Notter, D R

    2010-09-01

    Market lambs from the state fair of Virginia (n = 172) were ultrasonically evaluated by 4 scan technicians and 3 image interpreters to determine accuracy of ultrasonic estimates of loin muscle area (ULMA), backfat thickness (UBF), and body wall thickness (UBW). Lambs were initially scanned at the preferred magnification setting of each technician; 2 chose 1.5x and 2 chose 2.0x. Lambs were then scanned a second time for ULMA and UBF with machine magnification settings changed from 1.5 to 2.0x, or vice versa, midway through the second scan. Lambs were then slaughtered, and analogous measurements [carcass loin muscle area, carcass backfat thickness, and carcass body wall thickness (CBW)] were recorded on chilled carcasses. Pooled, residual correlation coefficients within technicians and interpreters between ultrasonic measurements from the first scan and carcass measurements were 0.66 for loin muscle area, 0.78 for backfat thickness, and 0.73 for body wall thickness, but were reduced to 0.43, 0.69, and 0.50, respectively, by inclusion of linear effects of carcass weight in the model. Mean bias for technicians and interpreters ranged from -1.30 to -2.66 cm(2) for loin muscle area, -0.12 to -0.17 cm for backfat thickness, and 0.14 to -0.03 cm for body wall thickness; prediction errors ranged from 1.86 to 2.22 cm(2), 0.12 to 0.14 cm, and 0.35 to 0.38 cm, respectively. Pooled correlations between repeated measures were 0.67 for ULMA, 0.79 for UBF, and 0.68 for UBW at the same magnification and 0.73 for ULMA and 0.76 for UBF across different magnification settings. Mean differences between repeated measures were more variable among technicians and interpreters than statistics comparing ultrasound to carcass measures. Standard errors of repeatability ranged from 1.61 to 2.45 cm(2) for ULMA, 0.07 to 0.11 cm for UBF, and 0.36 to 0.42 cm for UBW. The effect of changing magnification setting on technician and interpreter repeatability was small for UBF and ULMA. The accuracy of prediction of CBW from UBW was similar to that achieved for backfat thickness; further assessment of the value of ultrasonic measurements of body wall thickness in lambs is warranted. These results indicate that ultrasound scanning can reliably predict carcass loin muscle area and backfat thickness in live lambs and, accordingly, has value in selection programs to improve composition. Development of certification standards for US lamb ultrasound technicians based on results of this study and others is proposed.

  19. Technical success and short-term results of surgical treatment of gastrointestinal stromal tumors: an experience of three centers.

    Science.gov (United States)

    Gluzman, Mark Igorevich; Kashchenko, Victor Anatolevich; Karachun, Aleksei Mikhailovich; Orlova, Rashida Vakhidovna; Nakatis, Iakov Aleksandrovich; Pelipas, Iurii Vasilevich; Vasiukova, Evgenia Leonidovna; Rykov, Ivan Vladimirovich; Petrova, Veronika Vladimirovna; Nepomniashchaia, Svetlana Leonidovna; Klimov, Anton Sergeevich

    2017-01-01

    Gastrointestinal stromal tumors (GIST) comprise about 80% of gastrointestinal sarcomas. In patients with localized disease, surgery is considered as "Gold Standard" treatment. Organ-sparing radical en-block resection is widely accepted practice. Since lymph node dissection is not routinely indicated, minimally invasive approach is of particular interest. The aim of this study is to investigate the short-term outcomes of different surgical treatment of GISTs. We analyzed data of 116 patients who received surgical treatment for localized forms of GIST. Tumors were located in the stomach in 87 (75%) cases, in the small intestine in 26 (22.4%) cases, and extragastrointestinal GISTs were found in 3 (2.6%) patients. Four different approaches were used-open surgery (OpS, n=48), laparoscopic surgery (LS, n=40), endoscopic procedures (EP, n=22) and hybrid rendezvous (HR, n=6). Patient demographics, clinical presentation of tumors, characteristics of operation procedures (duration, intraoperative blood loss, frequency of R0-resection and fragmentation of tumor), postoperative complications and length of hospital stay were examined in all these groups. Radical treatment (R0-resection) was performed in all patients. There were no cases of tumor ruptures during surgical procedure. Mean size of GIST in OpS was 9.1±2.0 [2-35] cm; in LS: 4.9±0.8 (1.5-15) cm; in HR: 3.5±0.8 (2-4.5) cm and in EP: 2.3±0.3 (0.4-3.5) cm. Intraoperative blood loss in OpS was 369.7±209.5 [0-4,000] mL; LS: 63.9±16.0 [0-150] mL; in HR: 96.7±44.3 [50-200] mL; in EP: 33.3±11.0 [0-150] mL. Duration of operation in OpS was 160±20.4 [50-310] min; in LS: 104.7±12.7 [50-185]; in HR: 176.7±44.0 [110-260] min and in EP: 89.8±15.5 [25-190] min. Complication rate in OpS was 5 (10.4%); in LS: 3 (7.5%); in HR: 0% and in EP: 3 (13.6%). Length of hospital stay in OpS was 13.8±2.2 [7-52] days; in LS: 11, 4±2.2 [4-21] days; in HR: 11±3.2 [7-15] days and in EP: 11, 9±2.1 [5-22] days. There were no postoperative deaths. There is a diversity of surgical approaches for GISTs treatment. From our point of view, the main selection criteria for certain procedure are size, localization, growth type of the tumor and status of overlying mucosa. Nevertheless, due to relative rarity and heterogeneity of this pathology, individualization is necessary in each specific case. Laparoscopic and endoscopic surgery is proved to be safe and feasible for resection of the gastric GISTs, with a reasonable operation time, low blood loss, and an acceptable complication rate. Immediate results indicate that all interventions were performed radically without mortality or serious morbidity.

  20. PLANT SPACING AND WEED MANAGEMENT TECHNIQUES INFLUENCE WEED COMPETITIVENESS OF DRUM SEEDED RICE (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    B N Sandeep Nayak

    2014-11-01

    Full Text Available Direct wet seeded-rice sown through drum seeder, a potential wise rice production system in the present-day scenario, is subject to severe weed infestation and, therefore, development of a sustainable weed management strategy is crucial for its wide spread adoption. The present study was conducted in kharif 2012 at department of agronomy division with NLR-33358 (SOMASILA using six planting densities under five weed management conditions. The plant spacing tried were: 20cm x 7cm, 20 cm x 10.5 cm, 20 cm x 14 cm, 20 cm x 17.5 cm and 20 cm x 24.5cm and 20 cm x15cm. with a plant density of 71, 47, 35, 28, 20 and 33 hills m-2, respectively and five weed management practices viz., weedy check (W1, hand weeding at 20 and 40 DAS (W2, cono weeding at 20 and 40 with modified cono weeder (W3, pre-emergence application of anilofos @ 0.375 kg a.i ha-1 followed by post-emergence application of 2, 4 D sodium salt @ 1.0 kg a.i ha-1 20-25 DAS (W4, pre-emergence application of pendimethalin @1.0 kg a.i ha-1 followed by post-emergence application of bispyribac sodium @ 20 g a.i ha-1 30 DAS ( W5. . The experiment was laid out in strip- plot design with three replications assigning weed management techniques in vertical factor and plant spacing in horizontal factor. Direct wet seeded rice field was infested with 12 and 22 weed species, kharif -2012 season having Echinochloa colona, Leptochloa chinensis, Digitaria aescendens, Cyperus iriaand Eleusine indicaas the predominant weeds. Rice spacing exerted significant influence on both weed pressure and yield performance of crop. With the increase in plant spacing weed dry matter decreased but rice yield increased. In this season, among different plant densities, the highest density of 71 hills m-2(D1 resulted in minimum weed density, weed drymatter, and more number of tillers m-2 and maximum drymatter production at all stages of plant growth. closest spacing resulted in maximum weed suppression, but among various rice plant densities, a medium level population of 47 hills m-2 (D2 significantly increased the paddy yield over all other treatments except D1 treatments with a plant density of 71 hills m-2 .The highest grain yield of 3476 kg ha-1 was observed with a plant density of 47 hills m-2 and it was significantly superior to 71, 35, 28, 20 hills m-2drum seeded and 33 hills m-2 transplant paddies. which ultimately produced the highest rice yield. Weed inflicted relative yield loss was also minimized by the closest spacing. Present findings imply rice spacing mostly determines rice-weed competition, and can play a decisive role to minimize weed pressure. Therefore, closer spacing could be considered as a vital tool in the integrated weed management program for direct wet-seeded rice sown through drum seeder.

  1. Case Analysis of a Giant Myoepithelial Carcinoma in Nasal Cavity and Nasal Sinus%侵及鼻腔鼻窦的罕见巨大肌上皮癌病例分析

    Institute of Scientific and Technical Information of China (English)

    刘娅; 郭红光; 宁浩勇; 李进让

    2014-01-01

    Objective To study the clinical characteristics, diagnosis and management of myoepithelial carcinoma in nasal cavity and nasal sinus;to prevent misdiagnosis or mistherapy. Methods Retrospectively analysis of the clinical data of a patient with giant myoepithelial carcinoma in nasal cavity undergoing surgical removal was made. Results The patient was a 56-year-old male with a giant massive protruding from his face for 3 years and intermittent hemorrhage for 1 month. After careful examination of the head and neck region and assaying the results of computer tomography ( CT) as well as magnetic resonance imaging ( MRI) , malignancy from pleomorphic adenoma in minor salivary glands or other rare tumors was suspec-ted. Sufficient preoperative preparations were performed, including multi-disciplinary consultation, sufficient volume of blood and transvascular embolization. The giant 3 kg mass of 24. 5 cm × 16. 0 cm × 12. 0 cm was successfully removed by surgery. The pathological diagnosis was myoepithelial carcinoma ( invading nasal cavity and sinus) . Conclusion Attention should be paid to unilateral nasal cavity and nasal sinus tumor;and immunohistochemistry is helpful for early diagnoses and therapy.%目的:探讨鼻腔鼻窦肌上皮癌的诊治要点,防范误诊误治。方法对行手术切除的1例巨大鼻腔鼻窦肌上皮癌的临床资料进行回顾性分析,并复习国内外相关文献。结果本例为56岁男性,因左侧面部凸出巨大肿物3年余,肿物表面间断出血1个月入院。根据专科查体情况及鼻窦CT、MRI检查结果考虑来源于小涎腺的多形性腺瘤恶变或其他罕见肿瘤。经充分术前准备,包括多学科会诊、备足血源、术前肿瘤血管栓塞,术中完整切除一重3 kg、约24.5 cm ×16.0 cm ×12.0 cm大小的肿瘤。术后病理诊断:肌上皮癌(侵及鼻腔鼻窦)。结论鼻科医师应警惕单侧鼻腔鼻窦病变,加强对肌上皮癌病理特点及免疫组织化学的认识,以期对该病早诊断、早治疗。

  2. Multibeam tomotherapy: a new treatment unit devised for multileaf collimation, intensity-modulated radiation therapy.

    Science.gov (United States)

    Achterberg, Nils; Müller, Reinhold G

    2007-10-01

    organ-at-risk sparing, and comparable mean integral dose to the normal tissue a reduction in treatment time by more than 50% to only a few minutes in comparison to high-quality 3-D conformal and IMRT treatments. As a result, it will be possible to incorporate features for better patient positioning and image guidance, while sustaining reasonable overall treatment times at the same time. The virtual multibeam tomotherapy design study TOM'5-CT contains a dedicated electron beam CT (TOM'AGE) and an objective optical topometric patient positioning system (TOPOS). Thanks to the wide gantry bore of 120 cm and slim gantry depths of 70 cm, patients can be treated very comfortably, in all cases tumor-isocentrically, as well as with noncoplanar beam arrangements as in stereotactic radiosurgery with a couch rotation of up to +/- 54 degrees. The TOM'5 treatment unit on which this theoretical concept is based has a stand-alone depth of 40 cm and an outer diameter of 245 cm; the focus-isocenter distance of the heads is 100 cm with a field size of 40 cm x 7 cm and 0.5 cm leaves, which operate perpendicular to the axis of table motion.

  3. Effects of two-step alkaline pretreatment on components and structure of corn stover%两步碱法预处理对玉米秸秆组分及结构的影响

    Institute of Scientific and Technical Information of China (English)

    朱圆圆; 顾夕梅; 朱均均; 徐勇; 勇强; 余世袁

    2015-01-01

    Aimed at the effects of acetic acid on ethanol fermentation and its generation mechanism during the pretreatment process,sodium hydroxide combined with calcium hydroxide on the compositions and enzymatic hydrolysis of corn stover were in-vestigated.Corn stover after the first-step NaOH pretreatment could realize the removal of acetyl groups and separate acetic acid from the sugars from the source.The deacetylated corn stover further pretreated by Ca(OH)2 could improve the enzymatic hy-drolysis yield.And the fiber structure characteristics of corn stover were analyzed by Fourier transform infrared spectrometry (FT-IR),X-rays diffraction (XRD)and scanning electron microscope (SEM).The results showed that the removal of acetyl groups and the retention ratio of xylan were 95.2% and 87.8%,respectively and cellulose was not degraded after corn stover was pretreated by the first-step pretreatment.The optimal conditions of the second-step pretreatment of deacetylated corn stover by using orthogonal experiment were that calcium hydroxide dosage 0.100 g/g(based on dry corn stover),reaction temperature 90℃ and time 36 h.The corresponding enzymatic hydrolysis yield of 36 h was 85.1%.The obtained recovery yields of cellulose and hemicellulose in the solid residue were 92.1% and 65.5%,respectively and the lignin remove ratio was 63.0%.The fiber surface was rough and appeared a large number of cracks and slivers,separation occur between fiber bundles of corn stover after two-step alkaline pretreatment.The relative crystallization degree of corn stover increased from 55.1% to 60.6%,and the stretching vi-bration peak of C=O group at 1 245 cm-1 decreased significantly due to the removal of acetyl group.Combined with the increase of enzymatic yield,it also indicated that this two-step pretreatment could improve access of cellulose to cellulase.%针对乙酸对乙醇发酵的影响及其在预处理过程中的产生机制,采用氢氧化钠-氢氧化钙2

  4. Transmutation of radioactive nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Toor, A; Buck, R

    2000-03-15

    Lack of a safe disposal method for radioactive nuclear waste (RNW) is a problem of staggering proportion and impact. A typical LWR fission reactor will produce the following RNW in one year: minor actinides (i.e. {sup 237}Np, {sup 242-243}Am, {sup 243-245}Cm) {approx}40 kg, long-lived fission products (i.e, {sup 99}Tc, {sup 93}Zr, {sup 129}I, {sup 135}Cs) {approx}80 kg, short lived fission products (e.g. {sup 137}Cs, {sup 90}Sr) {approx}50kg and plutonium {approx}280 kg. The total RNW produced by France and Canada amounts to hundreds of metric tonnes per year. Obtaining a uniform policy dealing with RNW has been blocked by the desire on one hand to harvest the energy stored in plutonium to benefit society and on the other hand the need to assure that the stockpile of plutonium will not be channeled into future nuclear weapons. In the meantime, the quantity and handling of these materials represents a potential health hazard to the world's population and particularly to people in the vicinity of temporary storage facilities. In the U.S., societal awareness of the hazards associated with RNW has effectively delayed development of U.S. nuclear fission reactors during the past decade. As a result the U.S. does not benefit from the large investment of resources in this industry. Reluctance to employ nuclear energy has compelled our society to rely increasingly on non-reusable alternative energy sources; coal, oil, and natural gas. That decision has compounded other unresolved global problems such as air pollution, acid rain, and global warming. Relying on these energy sources to meet our increasing energy demands has led the U.S. to increase its reliance on foreign oil; a policy that is disadvantageous to our economy and our national security. RNW can be simplistically thought of as being composed of two principal components: (1) actinides with half lives up to 10{sup 6} years and (2) the broad class of fission fragments with typical half lives of a few hundred

  5. Sr, C and O isotopes as markers of alkaline disturbances in the Toarcian argillites of the Tournemire experimental platform (France). Case of a 15-years old engineered analogue.

    Science.gov (United States)

    Techer, I.; Boulvais, P.; Bartier, D.; Tinseau, E.

    2009-04-01

    argillites close to the cement-concrete contact. These data are detailed in another session of this meeting (Techer et al., ERE6 session). In order to precise the spatial extent of the disturbances and to discuss the nature of the responsible fluids, a systematic chemical and isotopic study was performed focusing on the Sr, C and O isotopes known to be very good markers of alkaline fluids percolation (Fourcade et al. 2006). Four studied levels were selected according to their location on the DM overcore and the nature of the cementitious material in contact to the argillites: -155 cm level (DM155) and -180 cm level (DM180) where argillites were in contact with a 1.5 to 3 cm thick concrete; -245 cm level (DM245) and -300 cm level (DM300) where the cementitious material was represented by a fine grained Portland cement 2 to 5 cm thick. Samples of the cementitious materials were collected at each level. Argillites were sampled perpendicularly to the cement-concrete contact with a continuous sampling every 2 to 5 mm millimeters (P1). Micro-fissures developed perpendicularly to the cement-concrete contact were opened and infilling secondary minerals were collected by scrap as a function of the distance to the cement-concrete (P3). Along P1 and P3, no significant variation of the carbonates d18O isotopic values was observed in the argillites. On the opposite d13C and 87Sr/86Sr values of these minerals changed significantly in the direct contact with the cement-concrete over a distance of 15 to 25 mm. Beyond this distance, argillites were again well bedded and showed values similar to those measured in a reference sample. Negative d13C values measured in the disturbed zone and close to those encountered in the cement and the concrete argued for a perturbation induced by an alkaline solution. 87Sr/86Sr isotopic ratios showed a progressive evolution in the disturbed zone, with increasing trends towards the cementitious material. Thanks to complementary Sr elementary contents

  6. Applying Advanced Neutron Transport Calculations for Improving Fuel Performance Codes

    Energy Technology Data Exchange (ETDEWEB)

    Botazzoli, P.; Luzzi, L. [Politecnico di Milano, Department of Energy, Nuclear Engineering Division - CeSNEF, Milano (Italy); Schubert, A.; Van Uffelen, P. [European Commission, Joint Research Centre, Institute for Transuranium Elements, Karlsruhe (Germany); Haeck, W. [Institute de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France)

    2009-06-15

    depletion code with any version of MCNP or MCNPX for reaction rate calculation. By means of a new efficient approach to Monte Carlo burn-up implemented into VESTA (the multi-group binning approach), the speed and accuracy of any burn-up and activation calculation has been drastically improved to an optimal level. One of the MOX configurations (with a Pu content of 5.6%) and the 3.5% enriched UO{sub 2} have been selected to be simulated by means of the VESTA code both considering the ENDF/B VII.0 and the JEFF 3.1 libraries. Considering the concentrations and the cross sections computed by VESTA, an overestimation in the TRANSURANUS formula can be noticed at the end of the irradiation history due to the fact that only the main fissile isotopes are considered, but at high burn-ups (especially for the MOX fuels), also the fissions of {sup 242m}Am and {sup 245}Cm play a non-negligible role thanks to their high fission cross sections. Including these isotopes the agreement is satisfactory. As a second step, in order to check the correctness of the implemented models, the fission and capture cross sections computed by VESTA have been fitted as a function of burn-up and implemented in the TRANSURANUS code. The results of the TRANSURANUS code have been compared with VESTA. The agreement of the predictions of all the considered isotopes is good, and the overestimation of the Helium production has been eliminated. Two conclusions can be drawn from the present analysis: - The ENDF/B VII.0 library as well as the ORIGEN fission yield database does not consider the ternary fission yield. Hence the results obtained by VESTA with the ENDF/B VII.0 library or with the ORIGEN fission yield database have to be corrected adding the ternary fission contribution. - The set of nuclides selected in TUBRNP are sufficient for a satisfactory description of the nuclide concentrations. As a final step, a sensitivity analysis has been performed by means of the Taguchi method. In particular, the effect of

  7. Electrochemical removal of Cd from bioashes in pilot scale and evaluation of possibilities for utilizing treated ashes in concrete; Elektrokemisk fjernelse af Cd fra bioasker i pilotskala og vurdering af mulighederne for nyttiggoerelse af behandlet aske i beton

    Energy Technology Data Exchange (ETDEWEB)

    Juul Pedersen, A.; Ottosen, L.M. [BYG-DTU, Copenhagen (Denmark); Simonsen, P. [Energi E2 A/S, Copenhagen (Denmark); Aune, J. [MT Hoejgaard A/S, Soeborg (Denmark)

    2006-07-01

    Electrochemical removal of cadmium from bio ashes has been demonstrated in pilot scale, and the remediated ashes have been evaluated for possible reuse as either fertilizers, or in concrete products. 5 remediation experiments have been completed, using straw combustion fly ash or fly ash from cocombustion of wood and fuel oil. During these emediation experiments the process has been upscaled stepwise, from an initial distance between the electrodes of 35 cm and a tank volume of 300 L ash suspension, to a final electrode distance of 245 cm, a total tank volume of 2.1 m3, and inclusion of up to 6 'concentration-units'. The ash volumes to be remediated made up to between 8.4 and 82.5 kg dry matter, prior to eventual pre-wash. The first four remediation experiments were made with straw combustion fly ash, the fifth contained both straw combustion fly ash and cocombustion fly ash, in separate compartments. The demonstration experiments have in many ways confirmed the results obtained in smaller scale in the previous project PSO FU 3206. It is demonstrated that electrochemical removal of cadmium from bioashes is possible also in larger scale than laboratory scale and benchscale, as final concentrations of cadmium below the regulatory limits for recycling of straw ashes have been reached. Furthermore, new findings such as the importance of choosing more acid resistant materials for the plant have showed up. The use of concentration units contributed positively to the separation of cadmium from the ash suspension, but when using concentration units the 'natural' acidification of the ash during the remediation process is delayed, and thus it is recommended to add acid to the ash before and eventually during the remediation process to decrease pH more rapidly. The ashes were analyzed before and after remediation for evaluation of the potential of reusing the ashes in concrete products, or recycle them as fertilizers. It was found that the fertilizing

  8. Soil fertility and {sup 137} Cs redistribution as related to land use, landscape and texture in a watershed of Paraiba State; Fertilidade do solo e redistribuicao de {sup 137} Cs em funcao da cobertura vegetal, relevo, e classes texturais, em uma microbacia hidrografica do Estado da Paraiba

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Antonio Clementino dos

    2004-03-15

    Intensive land use and growing deforestation of the natural vegetation in Northeastern Brazil have contributed to the degradation of resources, particularly the decrease of soil fertility. As a result, biodiversity and ecosystem capacity to restore its resources after disturbances have been diminished. The decrease in soil fertility is more substantial in areas dominated by an undulating topography. In these areas, erosion is intensified when crops or pasture replaces natural vegetation. Even though degradation processes are reflected in environmental, social, and economical changes, there is a lack of information regarding the interrelationship between these changes and soil fertility and erosion. Thus, the 'Vaca Brava' watershed (14,04 km{sup 2}), located in the 'Agreste' region of Paraiba State, was selected to study the interrelationships between land use, landscape, particle size distribution, soil fertility and erosion using {sup 137} Cs redistribution. Small farms, where subsistence agriculture is intensive, are common in this watershed, as well as areas for environmental protection. A georreferenced survey of the watershed topography was initially carried out. Based on the survey data, the watershed was digitalized using a scale of 1:5000, and a 3-D map was created. Each landform element had its area determined on a area (absolute value) and percentage (relative value) basis. Shoulder, backslope and footslope positions represented 83% of the cultivated area in the watershed. A data base of 360 georreferenced soil samples (0-20 cm), collected using a stratified sampling scheme, was further created. Sites were stratified based on their landscape position (summit, shoulder, backslope, footslope, and toeslope) in factorial combination with land use (annual crops, pasture, Pennisetum purpureum, Mimosa caesalpiniae folia, bush fallow, and native forest). Physical analyses of the soil samples included particle size distribution and bulk density, whereas soil chemical analyses were total C and N, extractable P (Mehlich-1), pH (water, exchangeable acidity and cations). The soils of the watershed generally exhibited low fertility, regardless of their landscape position (p<0.05). However, land use and texture contributed significantly to the soil fertility (p<0.05). The contents of C, N, Ca, Mg, and ECEC were significantly higher (p<0.05) for the forest soils, whereas P, K, and exchangeable acidity were higher (p<0,05) in the cultivated soils. Forest soils were classified as sandy clay and sandy clay loam (65%), whereas cultivated soils were identified as sand and sandy loam (64%). Particle size distribution and topography were interrelated as sand contents decreased with the increase in slope. Overall, soils with finer texture showed higher fertility levels, regardless of the landscape position. Catchment sites were not discriminated as areas of significant gain of nutrients. It was observed a strong P deficiency, regardless of the landscape position, land use or particle size distribution. The catena segmentation, based on landform elements, land use and soil depths, was an efficient tool to understand the erosion/sedimentation processes by using the {sup 137} Cs redistribution approach. Soils of the topossequences under native forest (n 2) and pasture (n = 3) were sampled for this purpose. It was observed a significant correlation between clay content and {sup 137} Cs activity in the soil (r = 0.75, p<0.01). At the summit positions of the forest soil, the average {sup 137} Cs stock down to a depth of 28 cm was 38,7 Bq m{sup -2}. At the backslope positions the {sup 137} Cs stock was similar for the same depth range. On the other hand, the average {sup 137} Cs stock in soils under pasture at the summit landscape position was 58,0 Bq m{sup -2}, with a maximum of 74,9 Bq m{sup -2}. Levels of {sup 137} Cs were below detection limit (0,03 Bq kg{sup -1}) on soils under pasture from the shoulder and backslope positions. The redistribution of {sup 137} Cs within the shoulder landscape position resulted in an estimated loss of 219,7 kg soil m{sup -2}, which is equivalent to a soil layer of 20,0 cm. Soil losses were higher on the backslope position, which reached a value of 268 kg m{sup -2}. This loss corresponds to the removal of a 24,5 cm soil layer. Given that the topossequences were representative of the area, these results indicate intense sediment redistribution within the watershed, which probably caused the transport of organic matter and nutrients associated with the clay fraction into the fluvial system. (author)