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Sample records for barium 137 target

  1. Targeting CD137 enhances the efficacy of cetuximab

    Science.gov (United States)

    Kohrt, Holbrook E.; Colevas, A. Dimitrios; Houot, Roch; Weiskopf, Kipp; Goldstein, Matthew J.; Lund, Peder; Mueller, Antonia; Sagiv-Barfi, Idit; Marabelle, Aurelien; Lira, Ruth; Troutner, Emily; Richards, Lori; Rajapaska, Amanda; Hebb, Jonathan; Chester, Cariad; Waller, Erin; Ostashko, Anton; Weng, Wen-Kai; Chen, Lieping; Czerwinski, Debra; Fu, Yang-Xin; Sunwoo, John; Levy, Ronald

    2014-01-01

    Treatment with cetuximab, an EGFR-targeting IgG1 mAb, results in beneficial, yet limited, clinical improvement for patients with head and neck (HN) cancer as well as colorectal cancer (CRC) patients with WT KRAS tumors. Antibody-dependent cell-mediated cytotoxicity (ADCC) by NK cells contributes to the efficacy of cetuximab. The costimulatory molecule CD137 (4-1BB) is expressed following NK and memory T cell activation. We found that isolated human NK cells substantially increased expression of CD137 when exposed to cetuximab-coated, EGFR-expressing HN and CRC cell lines. Furthermore, activation of CD137 with an agonistic mAb enhanced NK cell degranulation and cytotoxicity. In multiple murine xenograft models, including EGFR-expressing cancer cells, HN cells, and KRAS-WT and KRAS-mutant CRC, combined cetuximab and anti-CD137 mAb administration was synergistic and led to complete tumor resolution and prolonged survival, which was dependent on the presence of NK cells. In patients receiving cetuximab, the level of CD137 on circulating and intratumoral NK cells was dependent on postcetuximab time and host FcyRIIIa polymorphism. Interestingly, the increase in CD137-expressing NK cells directly correlated to an increase in EGFR-specific CD8+ T cells. These results support development of a sequential antibody approach against EGFR-expressing malignancies that first targets the tumor and then the host immune system. PMID:24837434

  2. Metabolism of {sup 137}cesium, {sup 137}barium in the rat. Therapeutics of the contamination; Metabolisme du {sup 137}cesium, {sup 137}baryum chez le rat. Therapeutique de la contamination

    Energy Technology Data Exchange (ETDEWEB)

    Remy, J.; Philippon, A.; Lafuma, J.; Walter, C. [Commissariat a l' Energie Atomique, 92 - Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires. Departement de la Protection Sanitaire, Laboratoire de Radiopathologie

    1967-07-01

    The authors carry out research into the distribution kinetics, the metabolism and the excretion of {sup 137}Cs - {sup 137}Ba in the rat. They show that these phenomena are independent of the method of applying a single dose. The distribution tends to adopt in all cases a typical shape which remains the same depending on the body burden. Biological analysis of the state of the cesium in the biological media shows that it is transported in the free and ionised form. Considering the problem of the method of penetration of the cesium ion in the intracellular medium, and in particular by the in vivo and in vitro kinetic study of the plasma - red cell system, the authors make the assumption that an active transport of cesium occurs by the cell membrane. They thus arrive at an overall picture of the cesium distribution in the organism which is essentially characterized by a dynamic distribution equilibrium between two compartments: 99 per cent of the cesium accumulates in the intracellular pool, 1 per cent in the extracellular liquids. This latter compartment is open to the emunctories. Because, of the active transport by the cell membranes, the intracellular pool is filled rapidly but discharge is slow. This phenomenon is the limiting factor in the decrease of the body burden. From this representation, the authors deduce the reasons for the relative failure of the various therapeutic methods examined up till now by themselves or by other authors. The stimulation of the natural emunctories in the case of diuretics for example, can only improve the purification of the extracellular compartment. Now this latter contains only 1 per cent of the body burden and recharging is slow. Furthermore the methods designed to counteract or inhibit the active transport of cesium by the cell membrane are still at the present time incompatible with the survival of the cell. (authors) [French] Les auteurs etudient experimentalement la cinetique de distribution, le metabolisme et l

  3. Potential Impact of miR-137 and Its Targets in Schizophrenia.

    Science.gov (United States)

    Wright, Carrie; Turner, Jessica A; Calhoun, Vince D; Perrone-Bizzozero, Nora

    2013-01-01

    The significant impact of microRNAs (miRNAs) on disease pathology is becoming increasingly evident. These small non-coding RNAs have the ability to post-transcriptionally silence the expression of thousands of genes. Therefore, dysregulation of even a single miRNA could confer a large polygenic effect. Schizophrenia is a genetically complex illness thought to involve multiple genes each contributing a small risk. Large genome-wide association studies identified miR-137, a miRNA shown to be involved in neuronal maturation, as one of the top risk genes. To assess the potential mechanism of impact of miR-137 in this disorder and identify its targets, we used a combination of literature searches, ingenuity pathway analysis (IPA), and freely accessible bioinformatics resources. Using TargetScan and the schizophrenia gene resource (SZGR) database, we found that in addition to CSMD1, C10orf26, CACNA1C, TCF4, and ZNF804A, five schizophrenia risk genes whose transcripts are also validated miR-137 targets, there are other schizophrenia-associated genes that may be targets of miR-137, including ERBB4, GABRA1, GRIN2A, GRM5, GSK3B, NRG2, and HTR2C. IPA analyses of all the potential targets identified several nervous system (NS) functions as the top canonical pathways including synaptic long-term potentiation, a process implicated in learning and memory mechanisms and recently shown to be altered in patients with schizophrenia. Among the subset of targets involved in NS development and function, the top scoring pathways were ephrin receptor signaling and axonal guidance, processes that are critical for proper circuitry formation and were shown to be disrupted in schizophrenia. These results suggest that miR-137 may indeed play a substantial role in the genetic etiology of schizophrenia by regulating networks involved in neural development and brain function. PMID:23637704

  4. Potential impact of miR-137 and its targets in schizophrenia

    Directory of Open Access Journals (Sweden)

    Carrie eWright

    2013-04-01

    Full Text Available The significant impact of microRNAs (miRNAs on disease pathology is becoming increasingly evident. These small non-coding RNAs have the ability to post-transcriptionally silence the expression of thousands of genes. Therefore, dysregulation of even a single miRNA could confer a large polygenic effect. Schizophrenia is a genetically complex illness thought to involve multiple genes each contributing a small risk. Large genome-wide association studies identified miR-137, a miRNA shown to be involved in neuronal maturation, as one of the top risk genes. To assess the potential mechanism of impact of miR-137 in this disorder and identify its targets, we used a combination of literature searches, Ingenuity Pathway Analysis (IPA, and freely accessible bioinformatics resources. Using TargetScan and the Schizophrenia Gene Resource (SZGR database, we found that in addition to CSMD1, C10orf26, CACNA1C, TCF4, and ZNF804A, five schizophrenia risk genes whose transcripts are also validated miR-137 targets, there are other schizophrenia-associated genes that may be targets of miR-137, including ERBB4, GABRA1, GRIN2A, GRM5, GSK3B, NRG2 and HTR2C. IPA analyses of all the potential targets identified several nervous system functions as the top canonical pathways including synaptic long-term potentiation, a process implicated in learning and memory mechanisms and recently shown to be altered in patients with schizophrenia. Among the subset of targets involved in nervous system development and function, the top scoring pathways were ephrin receptor signaling and axonal guidance, processes that are critical for proper circuitry formation and were shown to be disrupted in schizophrenia. These results suggest that miR-137 may indeed play a substantial role in the genetic etiology of schizophrenia by regulating networks involved in neural development and brain function.

  5. Barium Sulfate

    Science.gov (United States)

    Barium sulfate is used to help doctors examine the esophagus (tube that connects the mouth and stomach), stomach, and ... pictures of the inside of the body). Barium sulfate is in a class of medications called radiopaque ...

  6. miR-137, a new target for post-stroke depression?

    Institute of Scientific and Technical Information of China (English)

    Lixia Zhao; Huazi Li; Ruiyou Guo; Teng Ma; Rongyao Hou; Xiaowei Ma; Yifeng Du

    2013-01-01

    Expression of miR-137 is downregulated in brain tissue from patients with depression and suicidal behavior, and is also downregulated in peripheral blood from stroke patients. However, it is not yet known if miR-137 acts as a bridge between stroke and depression. To test this, we used middle cerebral artery occlusion and chronic mild stress to establish a post-stroke depression model in rats. Compared with controls, we found significantly lower miR-137 levels in the brain and peripheral blood from post-stroke depression rats. Injection of a miR-137 antagonist into the brain ventricles upregulated miR-137 levels, and improved behavioral changes in post-stroke depression rats. Lu-ciferase assays showed miR-137 bound to the 3′UTR of Grin2A, regulating Grin2A expression in a neuronal cel line. Grin2A gene overexpression in the brain of post-stroke depression rats, noticea-bly suppressed the inhibitory effect of miR-137 on post-stroke depression. Overal , our results show that miR-137 suppresses Grin2A protein expression through binding to Grin2A mRNA, thereby ex-erting an inhibitory effect on post-stroke depression. Our results offer a new therapeutic direction for post-stroke depression.

  7. Potential Impact of miR-137 and Its Targets in Schizophrenia

    OpenAIRE

    Wright, Carrie; Turner, Jessica A.; Calhoun, Vince D.; Perrone-Bizzozero, Nora

    2013-01-01

    The significant impact of microRNAs (miRNAs) on disease pathology is becoming increasingly evident. These small non-coding RNAs have the ability to post-transcriptionally silence the expression of thousands of genes. Therefore, dysregulation of even a single miRNA could confer a large polygenic effect. Schizophrenia is a genetically complex illness thought to involve multiple genes each contributing a small risk. Large genome-wide association studies identified miR-137, a miRNA shown to be in...

  8. Radioisotope analyzer of barium

    International Nuclear Information System (INIS)

    Principle of operation and construction of radioisotope barium sulphate analyzer type MZB-2 for fast determination of barium sulphate content in barite ores and enrichment products are described. The gauge equipped with Am-241 and a scintillation detector enables measurement of barium sulphate content in prepared samples of barite ores in the range 60% - 100% with the accuracy of 1%. The gauge is used in laboratories of barite mine and ore processing plant. 2 refs., 2 figs., 1 tab. (author)

  9. Evaluation of Transmutation of 137Cs(r,n) 136Cs Using Ultra-Intense Lasers in Solid Targets

    Institute of Scientific and Technical Information of China (English)

    R. Sadighi-Bonabi; O. Kokabee

    2006-01-01

    Relativistic electrons produced in ultra-intense laser-solid interaction generate highly collimated γ-ray beams through Bremsstrahlung that can be used to induce photonuclear reactions. Photonuclear transmutation (of (γ, n) type) of 137Cs, one of the hazardous nuclear wastes with half-life of 30.17 years which cannot be transmuted practically with neutron bombardment due to its very low neutron capture cross section, has been considered. Nuclear activity of produced 136Cs with half-life of 13.16 days has been evaluated analytically using available experimental data. With irradiating a 137Cs sample by p-polarized laser light of 1020 Wcm-2 and the repetition rate of 10 Hz for 30mm, the activity of 0.24 Bq is obtained. It is found that intensity has a large effect in yield around 1021 Wcm-2. For similar laser with intensity of 5×1021 Wcm-2, the activity increases with a factor of 105.

  10. Lower GI Series (Barium Enema)

    Science.gov (United States)

    ... barium into a bedpan or nearby toilet. A health care professional may give you an enema to flush out the rest of the barium. An x-ray technician and a radiologist perform a lower gastrointestinal (GI) series at a ...

  11. New barium tantalum sulphides

    International Nuclear Information System (INIS)

    The authors discuss a new barium tantalum sulphide, Ba3Ta2S8, prepared by sulphurization of a mixture of BaCO3 and Ta2O5. The electron and powder X-ray diffraction patterns of the compound are indexed on the basis of a monoclinic cell with lattice constants. A structure model is proposed. The refinement based on the powder X-ray diffraction intensities is performed

  12. Cesium-137

    International Nuclear Information System (INIS)

    This sheet belongs to a collection which relates to the use of radionuclides essentially in unsealed sources. Its goal is to gather on a single document the most relevant information as well as the best prevention practices to be implemented. These sheets are made for the persons in charge of radiation protection: users, radioprotection-skill persons, labor physicians. Each sheet treats of: 1 - the radio-physical and biological properties; 2 - the main uses; 3 - the dosimetric parameters; 4 - the measurement; 5 - the protection means; 6 - the areas delimitation and monitoring; 7 - the personnel classification, training and monitoring; 8 - the effluents and wastes; 9 - the authorization and declaration administrative procedures; 10 - the transport; and 11 - the right conduct to adopt in case of incident or accident. This sheet deals specifically with Cesium-137

  13. Individual-specific transgenerational marking of fish populations based on a barium dual-isotope procedure.

    Science.gov (United States)

    Huelga-Suarez, Gonzalo; Moldovan, Mariella; Garcia-Valiente, America; Garcia-Vazquez, Eva; Alonso, J Ignacio Garcia

    2012-01-01

    The present study focuses on the development and evaluation of an individual-specific transgenerational marking procedure using two enriched barium isotopes, (135)Ba and (137)Ba, mixed at a given and selectable molar ratio. The method is based on the deconvolution of the isotope patterns found in the sample into four molar contribution factors: natural xenon (Xe nat), natural barium (Ba nat), Ba135, and Ba137. The ratio of molar contributions between Ba137 and Ba135 is constant and independent of the contribution of natural barium in the sample. This procedure was tested in brown trout ( Salmo trutta ) kept in captivity. Trout were injected with three different Ba137/Ba135 isotopic signatures ca. 7 months and 7 days before spawning to compare the efficiency of the marking procedure at long and short term, respectively. The barium isotopic profiles were measured in the offspring by means of inductively coupled plasma mass spectrometry. Each of the three different isotopic signatures was unequivocally identified in the offspring in both whole eggs and larvae. For 9 month old offspring, the characteristic barium isotope signatures could also be detected in the otoliths even in the presence of a high and variable amount of barium of natural isotope abundance. In conclusion, it can be stated that the proposed dual-isotope marking is inheritable and can be detected after both long-term and short-term marking. Furthermore, the dual-isotope marking can be made individual-specific, so that it allows identification of offspring from a single individual or a group of individuals within a given fish group.

  14. On Barium Oxide Solubility in Barium-Containing Chloride Melts

    Science.gov (United States)

    Nikolaeva, Elena V.; Zakiryanova, Irina D.; Bovet, Andrey L.; Korzun, Iraida V.

    2016-08-01

    Oxide solubility in chloride melts depends on temperature and composition of molten solvent. The solubility of barium oxide in the solvents with barium chloride content is essentially higher than that in molten alkali chlorides. Spectral data demonstrate the existence of oxychloride ionic groupings in such melts. This work presents the results of the BaO solubility in two molten BaCl2-NaCl systems with different barium chloride content. The received data together with earlier published results revealed the main regularities of BaO solubility in molten BaO-BaCl2-MCl systems.

  15. MR Colonography with fecal tagging: Barium vs. barium ferumoxsil

    DEFF Research Database (Denmark)

    Achiam, M.P.; Chabanova, E.; Logager, V.B.;

    2008-01-01

    and Methods. Twenty patients referred to CC underwent dark lumen MRC prior to the colonoscopy. Two groups of patients received two different oral contrast agents (barium sulfate and barium sulfate/ferumoxsil) as a laxative-free fecal tagging prior to the MRC. After MRC, the contrast agent was rated...... qualitatively (with the standard method using contrast-to-wall ratio) and subjectively (using a visual analog scale [VAS]) by three different blinded observers. Results. Evaluated both qualitatively and subjectively, the tagging efficiency of barium sulfate/ferumoxsil was significantly better (P ... barium sulfate alone. The VAS method for evaluating the tagging efficiency of contrast agents showed a high correlation (observer 11, r = 0.91) to the standard method using contrast-to-wall ratio and also a high interclass correlation (observer 11 and III = 0.89/0.85). MRC found I of 22 (5%) polyps

  16. Doped barium titanate nanoparticles

    Indian Academy of Sciences (India)

    T K Kundu; A Jana; P Barik

    2008-06-01

    We have synthesized nickel (Ni) and iron (Fe) ion doped BaTiO3 nanoparticles through a chemical route using polyvinyl alcohol (PVA). The concentration of dopant varies from 0 to 2 mole% in the specimens. The results from X-ray diffractograms and transmission electron micrographs show that the particle diameters in the specimen lie in the range 24–40 nm. It is seen that the dielectric permittivity in doped specimens is enhanced by an order of magnitude compared to undoped barium titanate ceramics. The dielectric permittivity shows maxima at 0.3 mole% doping of Fe ion and 0.6 mole% of Ni ion. The unusual dielectric behaviour of the specimens is explained in terms of the change in crystalline structure of the specimens.

  17. New barium tantalum sulphides

    International Nuclear Information System (INIS)

    A new barium tantalum sulphide has been synthesized by the reaction of CS2 with a mixture of BaCO3 and Ta2O5. The chemical analysis of the compound was performed for 3 components (Ba, Ta and S), and the chemical composition was found to be BaTa2S5. The powder X-ray diffraction peaks were indexable on the basis of a hexagonal cell with lattices constants of a=3.32A, c=25.13A. However, the electron diffraction measurements show that the structure is more complex than that observed by powder X-ray diffraction. The compound indicates metallic behavior and Pauli paramagnetism

  18. Abundance analysis of barium and mild barium stars

    CERN Document Server

    Smiljanic, R; Silva, L

    2007-01-01

    High signal to noise, high resolution spectra were obtained for a sample of normal, mild barium, and barium giants. Atmospheric parameters were determined from the FeI and FeII lines. Abundances for Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, La, Ce, Nd, Sm, Eu, and Gd, were determined from equivalent widths and model atmospheres in a differential analysis, with the red giant Eps Vir as the standard star. The different levels of s-process overabundances of barium and mild barium stars were earlier suggested to be related to the stellar metallicity. Contrary to this suggestion, we found in this work no evidence for barium and mild barium to have a different range in metallicity. However, comparing the ratio of abundances of heavy to light s-process elements, we found some evidence that they do not share the same neutron exposure parameter. The exact mechanism controlling this difference is still not clear. As a by-product of this analysis we identify two normal red giants misclass...

  19. Discovery of the Barium Isotopes

    OpenAIRE

    SHORE, A.; A. Fritsch; Ginepro, J. Q.; Heim, M.; Schuh, A.; Thoennessen, M

    2009-01-01

    Thirty-eight barium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  20. Barium light source method and apparatus

    Science.gov (United States)

    Curry, John J. (Inventor); MacDonagh-Dumler, Jeffrey (Inventor); Anderson, Heidi M. (Inventor); Lawler, James E. (Inventor)

    2002-01-01

    Visible light emission is obtained from a plasma containing elemental barium including neutral barium atoms and barium ion species. Neutral barium provides a strong green light emission in the center of the visible spectrum with a highly efficient conversion of electrical energy into visible light. By the selective excitation of barium ionic species, emission of visible light at longer and shorter wavelengths can be obtained simultaneously with the green emission from neutral barium, effectively providing light that is visually perceived as white. A discharge vessel contains the elemental barium and a buffer gas fill therein, and a discharge inducer is utilized to induce a desired discharge temperature and barium vapor pressure therein to produce from the barium vapor a visible light emission. The discharge can be induced utilizing a glow discharge between electrodes in the discharge vessel as well as by inductively or capacitively coupling RF energy into the plasma within the discharge vessel.

  1. Decorporation of cesium-137

    International Nuclear Information System (INIS)

    Cesium radio-isotopes, especially cesium-137 (137Cs) are among the radionuclides of main importance produced by a fission reaction in reactor or a nuclear weapon explosion. In the environment, 137Cs is a major contaminant which can cause severe β, γirradiations and contaminations. 137Cs is distributed widely and relatively uniformly throughout the body with the highest concentration in skeletal muscles. A treatment becomes difficult afterwards. The purposes of this report are Firstly to compare the Prussian blue verses cobalt and potassium ferrocyanide (D.I. blue) efficiency for the 137Cs decorporation and secondly to assess a chronological treatment with D.I. blue. (author)

  2. Analysis of europium doped luminescent barium thioaluminate

    Institute of Scientific and Technical Information of China (English)

    张东璞; 喻志农; 薛唯; 章婷; 丁瞾; 王武育

    2010-01-01

    Europium-doped barium thioaluminate sputtering target was synthesized by powder sintering method and thin film was deposited by radio frequency(RF) sputtering.X-ray diffractometer(XRD) pattern indicated that the main compound of the target was BaAl4S7.Oxygen was the main impurity which led to the formation of BaAl2O4.It was shown that both BaAl4S7 and BaAl2S4 were contained in the as-grown thin films and a 471.7 nm emission peak in the PL spectra appeared due to a combination of BaAl4S7:Eu2+ and BaAl2S4:Eu2...

  3. Comparison of Barium and Arsenic Concentrations in Well Drinking Water and in Human Body Samples and a Novel Remediation System for These Elements in Well Drinking Water

    Science.gov (United States)

    Kato, Masashi; Kumasaka, Mayuko Y.; Ohnuma, Shoko; Furuta, Akio; Kato, Yoko; Shekhar, Hossain U.; Kojima, Michiyo; Koike, Yasuko; Dinh Thang, Nguyen; Ohgami, Nobutaka; Ly, Thuy Bich; Jia, Xiaofang; Yetti, Husna; Naito, Hisao; Ichihara, Gaku; Yajima, Ichiro

    2013-01-01

    Health risk for well drinking water is a worldwide problem. Our recent studies showed increased toxicity by exposure to barium alone (≤700 µg/L) and coexposure to barium (137 µg/L) and arsenic (225 µg/L). The present edition of WHO health-based guidelines for drinking water revised in 2011 has maintained the values of arsenic (10 µg/L) and barium (700 µg/L), but not elements such as manganese, iron and zinc. Nevertheless, there have been very few studies on barium in drinking water and human samples. This study showed significant correlations between levels of arsenic and barium, but not its homologous elements (magnesium, calcium and strontium), in urine, toenail and hair samples obtained from residents of Jessore, Bangladesh. Significant correlation between levels of arsenic and barium in well drinking water and levels in human urine, toenail and hair samples were also observed. Based on these results, a high-performance and low-cost adsorbent composed of a hydrotalcite-like compound for barium and arsenic was developed. The adsorbent reduced levels of barium and arsenic from well water in Bangladesh and Vietnam to <7 µg/L within 1 min. Thus, we have showed levels of arsenic and barium in humans and propose a novel remediation system. PMID:23805262

  4. Comparison of Barium and Arsenic Concentrations in Well Drinking Water and in Human Body Samples and a Novel Remediation System for These Elements in Well Drinking Water.

    Directory of Open Access Journals (Sweden)

    Masashi Kato

    Full Text Available Health risk for well drinking water is a worldwide problem. Our recent studies showed increased toxicity by exposure to barium alone (≤700 µg/L and coexposure to barium (137 µg/L and arsenic (225 µg/L. The present edition of WHO health-based guidelines for drinking water revised in 2011 has maintained the values of arsenic (10 µg/L and barium (700 µg/L, but not elements such as manganese, iron and zinc. Nevertheless, there have been very few studies on barium in drinking water and human samples. This study showed significant correlations between levels of arsenic and barium, but not its homologous elements (magnesium, calcium and strontium, in urine, toenail and hair samples obtained from residents of Jessore, Bangladesh. Significant correlation between levels of arsenic and barium in well drinking water and levels in human urine, toenail and hair samples were also observed. Based on these results, a high-performance and low-cost adsorbent composed of a hydrotalcite-like compound for barium and arsenic was developed. The adsorbent reduced levels of barium and arsenic from well water in Bangladesh and Vietnam to <7 µg/L within 1 min. Thus, we have showed levels of arsenic and barium in humans and propose a novel remediation system.

  5. Management of cesium loaded AMP- Part I preparation of 137Cesium concentrate and cementation of secondary wastes

    International Nuclear Information System (INIS)

    Separation of 137cesium from High Level Waste can be achieved by use of composite-AMP, an engineered form of Ammonium Molybdo-Phosphate(AMP). Direct vitrification of cesium loaded composite AMP in borosilicate glass matrix leads to separation of water soluble molybdate phase. A proposed process describes two different routes of selective separation of molybdates and phosphate to obtain solutions of cesium concentrates. Elution of 137Cesium from composite-AMP by decomposing it under flow conditions using saturated barium hydroxide was investigated. This method leaves molybdate and phosphate embedded in the column but only 70% of total cesium loaded on column could be eluted. Alternatively composite-AMP was dissolved in sodium hydroxide and precipitation of barium molybdate-phosphate from the resultant solution, using barium nitrate was investigated by batch methods. The precipitation technique gave over 99.9% of 137Cesium activity in solutions, free of molybdates and phosphates, which is ideally suited for immobilization in borosilicate glass matrix. Detailed studies were carried out to immobilize secondary waste of 137Cesium contaminated barium molybdate-phosphate precipitates in the slag cement matrix using vermiculite and bentonite as admixtures. The cumulative fraction of 137Cs leached from the cement matrix blocks was 0.05 in 140 days while the 137Cs leach rate was 0.001 gm/cm2/d. (author)

  6. Rationale for anti-CD137 cancer immunotherapy.

    Science.gov (United States)

    Makkouk, Amani; Chester, Cariad; Kohrt, Holbrook E

    2016-02-01

    The consideration of the complex interplay between the tumour microenvironment (TME) and the immune response is the key for designing effective immunotherapies. Therapeutic strategies that harness co-stimulatory receptors have recently gained momentum in the clinic. One such strategy with promising clinical applications is the targeting of CD137, a member of the tumour necrosis factor receptor superfamily. Its expression on both innate and adaptive immune cells, coupled with its unique ability to potentiate antitumour responses through modulating the TME and to ameliorate autoimmune responses, has established it as an appealing target. In this review, we will discuss the various CD137-targeted immunotherapeutics that have reached clinical development, with a focus on recent advances and novel modalities such as CD137 chimeric antigen receptors and CD137 bispecific antibodies. We will also highlight the effect of CD137 targeting on the TME and discuss the importance of probing TME changes for predicting and testing the efficacy of CD137-mediated immunotherapy.

  7. Radioisotope barium sulphate gauge MZB-2

    International Nuclear Information System (INIS)

    A method and the gauge for measuring content of barium sulphate are described. The gauge is intended for fast determination of barium sulphate in barite ore and in output products of the enrichment process. The measuring range 60-100% of BaSO4, accuracy ±1% and measuring time 60 s were reached. The barium sulphate gauge is used in barite mine ''Boguszow'' in Poland. (author)

  8. The problem of the barium stars

    Science.gov (United States)

    Bohm-Vitense, E.; Nemec, J.; Proffitt, C.

    1984-01-01

    Ultraviolet observations of barium stars and other cool stars with peculiar element abundances are reported. Those observations attempted to find hot white dwarf companions. Among six real barium stars studied, only Zeta Cap was found to have a white dwarf companion. Among seven mild, or marginal, barium stars studied, at least three were found to have hot subluminous companions. It is likely that all of them have white dwarf companions.

  9. Barium aspiration and alveolarisation of barium in an infant: A case report and review of management

    Directory of Open Access Journals (Sweden)

    Alan F. Isles

    2014-05-01

    Full Text Available We describe a case of bilateral inhalation and alveolarisation of barium in an infant following a barium swallow for investigation of dusky spells associated with feeds. A bronchoscopy subsequently revealed the presence of a mid-tracheal tracheo-oesophageal cleft. We review the literature on barium aspiration, its consequences and make recommendations for management.

  10. ONE CASE REPORT OF ACUTE POISONING BY BARIUM CARBONATE

    Institute of Scientific and Technical Information of China (English)

    GE Qin-min; BIAN Fan; WANG Shu-yun; SHEN Sheng-hui

    2009-01-01

    @@ Most barium poisoning cases were caused by oral intake by mistake. Recent years, barium carbonate poisoning has been rare to be reported. Here we reported a case of acute barium carbonate toxication taken orally on purpose.

  11. Cesium-137 in biosphere

    International Nuclear Information System (INIS)

    The behaviour of cesium-137 in environment is reviewed. Problems on 137Cs migration in environment, on metabolism andbiological effects are considered. Data on nuclide accumulation in various plants, ways of their entering the man's organism are presented. It is marked that the rate of 137Cs metabolism in the man's organism depends considerably on age, sex, temperature of environment, conditions for activity, water and mineral metabolism and some other factors. It is shown that the annual effective equivalent dose per capita will increase to 2000 yr. up to 1 μSv, that constitutes 0.05% of the average value of irradiation by a natural source

  12. Processing science of barium titanate

    Science.gov (United States)

    Aygun, Seymen Murat

    Barium titanate and barium strontium titanate thin films were deposited on base metal foils via chemical solution deposition and radio frequency magnetron sputtering. The films were processed at elevated temperatures for densification and crystallization. Two unifying research goals underpin all experiments: (1) To improve our fundamental understanding of complex oxide processing science, and (2) to translate those improvements into materials with superior structural and electrical properties. The relationships linking dielectric response, grain size, and thermal budget for sputtered barium strontium titanate were illustrated. (Ba 0.6Sr0.4)TiO3 films were sputtered on nickel foils at temperatures ranging between 100-400°C. After the top electrode deposition, the films were co-fired at 900°C for densification and crystallization. The dielectric properties were observed to improve with increasing sputter temperature reaching a permittivity of 1800, a tunability of 10:1, and a loss tangent of less than 0.015 for the sample sputtered at 400°C. The data can be understood using a brick wall model incorporating a high permittivity grain interior with low permittivity grain boundary. However, this high permittivity value was achieved at a grain size of 80 nm, which is typically associated with strong suppression of the dielectric response. These results clearly show that conventional models that parameterize permittivity with crystal diameter or film thickness alone are insufficiently sophisticated. Better models are needed that incorporate the influence of microstructure and crystal structure. This thesis next explores the ability to tune microstructure and properties of chemically solution deposited BaTiO3 thin films by modulation of heat treatment thermal profiles and firing atmosphere composition. Barium titanate films were deposited on copper foils using hybrid-chelate chemistries. An in-situ gas analysis process was developed to probe the organic removal and the

  13. Laser cooling and trapping of barium

    NARCIS (Netherlands)

    De, Subhadeep

    2008-01-01

    Laser cooling and trapping of heavy alkaline-earth element barium have been demonstrated for the first time ever. For any possible cycling transition in barium that could provide strong cooling forces, the excited state has a very large branching probability to metastable states. Additional lasers a

  14. CT-Guided Percutaneous Transthoracic Localization of Pulmonary Nodules Prior to Video-Assisted Thoracoscopic Surgery Using Barium Suspension

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Nyoung Keun; Park, Chang Min; Kang, Chang Hyun; Jeon, Yoon Kyung; Choo, Ji Yung; Lee, Hyun Ju; Goo, Jin Mo [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2012-11-15

    To describe our initial experience with CT-guided percutaneous barium marking for the localization of small pulmonary nodules prior to video-assisted thoracoscopic surgery (VATS). From October 2010 to April 2011, 10 consecutive patients (4 men and 6 women; mean age, 60 years) underwent CT-guided percutaneous barium marking for the localization of 10 small pulmonary nodules (mean size, 7.6 mm; range, 3-14 mm): 6 pure ground-glass nodules, 3 part-solid nodules, and 1 solid nodule. A 140% barium sulfate suspension (mean amount, 0.2 mL; range, 0.15-0.25 mL) was injected around the nodules with a 21-gauge needle. The technical details, surgical findings and pathologic features associated with barium localizations were evaluated. All nodules were marked within 3 mm (mean distance, 1.1 mm; range, 0-3 mm) from the barium ball (mean diameter, 9.6 mm; range, 8-16 mm) formed by the injected barium suspension. Pneumothorax occurred in two cases, for which one needed aspiration. However, there were no other complications. All barium balls were palpable during VATS and visible on intraoperative fluoroscopy, and were completely resected. Both the whitish barium balls and target nodules were identifiable in the frozen specimens. Pathology revealed one invasive adenocarcinoma, five adenocarcinoma-in-situ, two atypical adenomatous hyperplasias, and two benign lesions. In all cases, there were acute inflammations around the barium balls which did not hamper the histological diagnosis of the nodules. CT-guided percutaneous barium marking can be an effective, convenient and safe pre-operative localization procedure prior to VATS, enabling accurate resection and diagnosis of small or faint pulmonary nodules.

  15. Synthesis of barium titanium oxide from barium sulphate and anatase. Study of equimolar mixtures under different atmospheres

    International Nuclear Information System (INIS)

    To enable the ceramization of a barium sulphate-rich radioactive waste the synthesis of barium titanium oxide is studied by using anatase and barium sulphate. As a function of the calcination atmosphere, helium (or air) and Ar/H2, two reactions are studied. A mechanism of barium titanium oxide synthesis in helium (or in air) is proposed

  16. Double contrast barium meal and acetylcysteine

    International Nuclear Information System (INIS)

    In a prospective double blind study, acetylcysteine, a local and systemic respiratory tract mucolytic agent, or a placebo, were given to 100 patients prior to a double contrast barium meal to decrease the gastric mucus viscosity and to make the mucus layer thinner, in order to permit barium to outline the furrows surrounding the areae gastricae instead of the overlying thick mucus. However, acetylcysteine failed to improve either visualization of the areae gastricae or the general quality of the double contrast barium meal. (orig.)

  17. Neutral Barium Cloud Evolution at Different Altitudes

    Institute of Scientific and Technical Information of China (English)

    李磊; 徐荣栏

    2002-01-01

    Considering the joint effects of diffusion, collision, oxidation and photoionization, we study the evolution of the barium cloud at different altitudes in the space plasma active experiment. The results present the variation of the loss rate, number density distribution and brightness of the barium cloud over the range from 120 to 260km.This can be divided into oxidation, oxidation plus photoionization and photoionization regions.

  18. Small barium rail gun for plasma injection.

    Science.gov (United States)

    Kiwamoto, Y

    1980-03-01

    A small rail gun with a barium electrode can be operated at higher than one shot per second to produce more than 2x10(16) barium ions with energy 10-20 eV. The operation of the gun takes advantage of the external magnetic field for cross-field plasma injection into a trap. Up to 7 kG of the magnetic field examined, the gun performance improves with the increased magnetic field strength.

  19. Bacterial Reduction Of Barium Sulphate By Sulphate-Reducing Bacteria

    Directory of Open Access Journals (Sweden)

    Luptáková Alena

    2015-12-01

    Full Text Available Acid mine drainage (AMD is a worldwide problem leading to contamination of water sources. AMD are characterized by low pH and high content of heavy metals and sulphates. The barium salts application presents one of the methods for the sulphates removing from AMD. Barium chloride, barium hydroxide and barium sulphide are used for the sulphates precipitation in the form of barium sulphate. Because of high investment costs of barium salts, barium sulphide is recycled from barium sulphate precipitates. It can be recycled by thermic or bacterial reduction of barium sulphate. The aim of our study was to verify experimentally the possibility of the bacterial transformation of BaSO4 to BaS by sulphate-reducing bacteria. Applied BaSO4 came from experiments of sulphates removal from Smolnik AMD using BaCl2.

  20. Venous barium embolization, a rare, potentially fatal complication of barium enema: 2 case reports

    International Nuclear Information System (INIS)

    Venous embolization of barium has been recognized for 4 decades as one of the most dreaded complications of barium enema. Fortunately, the condition is extremely rare. In this report, the radiographic findings in 2 cases of venous embolization (one involving the portal vein and one systematic) are described, and ways to decrease the risk of this complication are discussed. (author)

  1. Thermochemical hydrogen production via a cycle using barium and sulfur - Reaction between barium sulfide and water

    Science.gov (United States)

    Ota, K.; Conger, W. L.

    1977-01-01

    The reaction between barium sulfide and water, a reaction found in several sulfur based thermochemical cycles, was investigated kinetically at 653-866 C. Gaseous products were hydrogen and hydrogen sulfide. The rate determining step for hydrogen formation was a surface reaction between barium sulfide and water. An expression was derived for the rate of hydrogen formation.

  2. Fabrication of thin target of 138Ba by vacuum evaporation

    International Nuclear Information System (INIS)

    Target fabrication is a highly sophisticated and crucial step in nuclear physics experiments. The success of any nuclear experiment is primarily determined by the quality and quantity of the target. 138Ba target is prepared for the evaporation residue cross section measurement of 188Pt populated through the reaction with 50Ti ion beam. Barium is a highly reactive metal and upon exposure to air at room temperature it will readily react with oxygen. Presently no information is available in the literature for the thin barium target fabrication through vacuum evaporation method. The two previous attempts available in literature were in sputtering method using barium nitrate or barium carbonate

  3. Synthesis of barium mercaptides and application of antimony/barium mercaptides

    Institute of Scientific and Technical Information of China (English)

    瞿龙; 张露露; 舒万艮

    2001-01-01

    Mercaptoacetic acid, isooctyl thioglycolate and barium hydroxide used as start materials, barium bis (2-ethylhexyl thioglycolate) (Ba(2EHTG)2), barium thioglycolate (Ba(TG)) and barium bisthioglycolate (Ba(TG)2) were synthesized. Their optimum synthetic techniques were discussed, and some physicochemical data were reported. Infrared spectroscopy and elemental analysis methods were used to identify the structures. They were put into PVC plastic products together with antimony tris (2-ethylhexyl thioglycolate) (Sb(2EHTG)3) under the suitable compounding, and their heat stability to PVC was studied. It is shown that these barium mercaptides have remarkable synergisms with antimony mercaptides and the long-term stabilizing effect of organoantimony stabilizer can be effectively improved, reducing the amount of antimony compounds so as to avoid the decrease of its stabilizing effect.

  4. Chemical abundances and kinematics of barium stars

    Science.gov (United States)

    de Castro, D. B.; Pereira, C. B.; Roig, F.; Jilinski, E.; Drake, N. A.; Chavero, C.; Sales Silva, J. V.

    2016-07-01

    In this paper, we present an homogeneous analysis of photospheric abundances based on high-resolution spectroscopy of a sample of 182 barium stars and candidates. We determined atmospheric parameters, spectroscopic distances, stellar masses, ages, luminosities and scaleheight, radial velocities, abundances of the Na, Al, α-elements, iron-peak elements, and s-process elements Y, Zr, La, Ce, and Nd. We employed the local thermodynamic equilibrium model atmospheres of Kurucz and the spectral analysis code MOOG. We found that the metallicities, the temperatures and the surface gravities for barium stars cannot be represented by a single Gaussian distribution. The abundances of α-elements and iron peak elements are similar to those of field giants with the same metallicity. Sodium presents some degree of enrichment in more evolved stars that could be attributed to the NeNa cycle. As expected, the barium stars show overabundance of the elements created by the s-process. By measuring the mean heavy-element abundance pattern as given by the ratio [s/Fe], we found that the barium stars present several degrees of enrichment. We also obtained the [hs/ls] ratio by measuring the photospheric abundances of the Ba-peak and the Zr-peak elements. Our results indicated that the [s/Fe] and the [hs/ls] ratios are strongly anticorrelated with the metallicity. Our kinematical analysis showed that 90 per cent of the barium stars belong to the thin disc population. Based on their luminosities, none of the barium stars are luminous enough to be an asymptotic giant branch star, nor to become self-enriched in the s-process elements. Finally, we determined that the barium stars also follow an age-metallicity relation.

  5. Improved thermal stability and wettability behavior of thermoplastic polyurethane / barium metaborate composites

    Energy Technology Data Exchange (ETDEWEB)

    Baştürka, Emre; Madakbaş, Seyfullah; Kahraman, Memet Vezir, E-mail: smadakbas@marmara.edu.tr [Department of Chemistry, Marmara University, Istanbul (Turkey)

    2016-03-15

    In this paper, it was targeted to the enhance thermal stability and wettability behavior of thermoplastic polyurethane (TPU) by adding barium metaborate. TPU-Barium metaborate composites were prepared by adding various proportions of barium metaborate to TPU. The chemical structures of the composites were characterised by fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. All prepared composites have extremely high Tg and thermal stability as determined from DSC and TGA analysis. All composite materials have the Tg ranging from 15 to 35 °C. The surface morphologies of the composites were investigated by a scanning electron microscopy. Mechanical properties of the samples were characterized with stress-strain test. Hydrophobicity of the samples was determined by the contact angle measurements. The obtained results proved that thermal, hydrophobic and mechanical properties were improved. (author)

  6. Improved thermal stability and wettability behavior of thermoplastic polyurethane / barium metaborate composites

    International Nuclear Information System (INIS)

    In this paper, it was targeted to the enhance thermal stability and wettability behavior of thermoplastic polyurethane (TPU) by adding barium metaborate. TPU-Barium metaborate composites were prepared by adding various proportions of barium metaborate to TPU. The chemical structures of the composites were characterised by fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. All prepared composites have extremely high Tg and thermal stability as determined from DSC and TGA analysis. All composite materials have the Tg ranging from 15 to 35 °C. The surface morphologies of the composites were investigated by a scanning electron microscopy. Mechanical properties of the samples were characterized with stress-strain test. Hydrophobicity of the samples was determined by the contact angle measurements. The obtained results proved that thermal, hydrophobic and mechanical properties were improved. (author)

  7. Coherent Dark Resonances in Atomic Barium

    CERN Document Server

    Dammalapati, U; Jungmann, K; Willmann, L

    2007-01-01

    The observation of dark-resonances in the two-electron atom barium and their influence on optical cooling is reported. In heavy alkali earth atoms, i.e. barium or radium, optical cooling can be achieved using n^1S_0-n^1P_1 transitions and optical repumping from the low lying n^1D_2 and n^3D_{1,2} states to which the atoms decay with a high branching ratio. The cooling and repumping transition have a common upper state. This leads to dark resonances and hence make optical cooling less inefficient. The experimental observations can be accurately modelled by the optical Bloch equations. Comparison with experimental results allows us to extract relevant parameters for effective laser cooling of barium.

  8. Suicide with cesium 137

    International Nuclear Information System (INIS)

    Report on first case of suicide with radioactive substance in Bulgaria is given. A defectoscopist with cyclothymic structure of character and psychotraumatic family environment made a second and successful attempt at suicide, this time by means of external irradiation with 137Cs with an activity of 5.3 C in the course of two hours. He irradiated his heart region and the first three fingers of his right hand. A grave picture of acute, local irradiation injury lasting four months with lethal outcome. The authors treat the psychological motives in the behaviour of these suicides and the reasons which determine the small number of suicide carried out with radioactive substance. (author)

  9. Refractory oxides containing aluminium and barium

    OpenAIRE

    Davies T.J.; Biedermann M.; Q-G. Chen; Emblem H. G.; Al-Douri W. A.

    1998-01-01

    Oxides containing aluminium and barium, optionally with chromium, are refractory with several possible industrial uses. A gel precursor of an oxide having the formula BaO.n(Al2xCr2yO3), where 1barium salt with a solution of an aluminium salt or a solution of an aluminium salt and a chromium III salt, then forming a gel which was fired to obtain the desired oxide. Filaments may be drawn as the gel is forming or extr...

  10. Electronic structure of nanograin barium titanate ceramics

    Institute of Scientific and Technical Information of China (English)

    DENG Xiangyun; WANG Xiaohui; LI Dejun; LI Longtu

    2007-01-01

    The density of states and band structure of 20 nm barium titanate(BaTiO3,BT)ceramics are investigated by first-principles calculation.The full potential linearized augmented plane wave(FLAPW)method is used and the exchange correlation effects are treated by the generalized gradient approximation(GGA).The results show that there is substantial hybridization between the Ti 3d and O 2p states in 20 nm BT ceramics and the interaction between barium and oxygen is typically ionic.

  11. Printed Barium Strontium Titanate capacitors on silicon

    Energy Technology Data Exchange (ETDEWEB)

    Sette, Daniele [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Luxembourg Institute of Science and Technology LIST, Materials Research and Technology Department, L-4422 Belvaux (Luxembourg); Kovacova, Veronika [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Defay, Emmanuel, E-mail: emmanuel.defay@list.lu [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Luxembourg Institute of Science and Technology LIST, Materials Research and Technology Department, L-4422 Belvaux (Luxembourg)

    2015-08-31

    In this paper, we show that Barium Strontium Titanate (BST) films can be prepared by inkjet printing of sol–gel precursors on platinized silicon substrate. Moreover, a functional variable capacitor working in the GHz range has been made without any lithography or etching steps. Finally, this technology requires 40 times less precursors than the standard sol–gel spin-coating technique. - Highlights: • Inkjet printing of Barium Strontium Titanate films • Deposition on silicon substrate • Inkjet printed silver top electrode • First ever BST films thinner than 1 μm RF functional variable capacitor that has required no lithography.

  12. Thermal decomposition of barium valerate in argon

    DEFF Research Database (Denmark)

    Torres, P.; Norby, Poul; Grivel, Jean-Claude

    2015-01-01

    The thermal decomposition of barium valerate (Ba(C4H9CO2)(2)/Ba-pentanoate) was studied in argon by means of thermogravimetry, differential thermal analysis, IR-spectroscopy, X-ray diffraction and hot-stage optical microscopy. Melting takes place in two different steps, at 200 degrees C and 280...

  13. 75 FR 19657 - Barium Chloride From China

    Science.gov (United States)

    2010-04-15

    ... Commission found that the domestic interested party group response to its notice of institution (74 FR 31757... COMMISSION Barium Chloride From China AGENCY: United States International Trade Commission. ACTION: Notice of... chloride from China. SUMMARY: The Commission hereby gives notice that it will proceed with a full...

  14. 75 FR 20625 - Barium Chloride From China

    Science.gov (United States)

    2010-04-20

    ... established a schedule for the conduct of this review (74 FR 62587, November 30, 2010). Subsequently, counsel... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Barium Chloride From China AGENCY: United States International Trade Commission. ACTION:...

  15. Decorporation of cesium-137; Decorporation du cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    Le Fleche, Ph.; Destombe, C.; Grasseau, A.; Mathieu, J.; Chancerelle, Y.; Mestries, J.C. [GMR, Direction des Recherches, Etudes et Techniques, 94 - Arcueil (France)

    1997-12-31

    Cesium radio-isotopes, especially cesium-137 ({sup 137}Cs) are among the radionuclides of main importance produced by a fission reaction in reactor or a nuclear weapon explosion. In the environment, {sup 137}Cs is a major contaminant which can cause severe {beta}, {gamma}irradiations and contaminations. {sup 137}Cs is distributed widely and relatively uniformly throughout the body with the highest concentration in skeletal muscles. A treatment becomes difficult afterwards. The purposes of this report are Firstly to compare the Prussian blue verses cobalt and potassium ferrocyanide (D.I. blue) efficiency for the {sup 137}Cs decorporation and secondly to assess a chronological treatment with D.I. blue. (author)

  16. Barium carbonate as an agent to improve the electrical properties of neodymium-barium-copper system at high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, J.P. [Post-Graduate Program in Chemical Engineering, Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC, 88040-900 (Brazil); Duarte, G.W. [Post-Graduate Program in Chemical Engineering, Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC, 88040-900 (Brazil); Research Group in Technology and Information, Centro Universitário Barriga Verde (UNIBAVE), Santa Catarina, SC (Brazil); Caldart, C. [Post-Graduate Program in Science and Materials Engineering, Universidade do Extremo Sul Catarinense (UNESC), Criciúma, SC, 88806-000 (Brazil); Kniess, C.T. [Post-Graduate Program in Professional Master in Management, Universidade Nove de Julho, São Paulo, SP (Brazil); Montedo, O.R.K.; Rocha, M.R. [Post-Graduate Program in Science and Materials Engineering, Universidade do Extremo Sul Catarinense (UNESC), Criciúma, SC, 88806-000 (Brazil); Riella, H.G. [Post-Graduate Program in Chemical Engineering, Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC, 88040-900 (Brazil); Fiori, M.A., E-mail: fiori@unochapeco.edu.br [Post-Graduate Program in Environmental Science, Universidade Comunitária da Região de Chapecó (UNOCHAPECÓ), Chapecó, SC, 89809-000 (Brazil); Post-Graduate Program in Technology and Management of the Innovation, Universidade Comunitária da Região de Chapecó (UNOCHAPECÓ), Chapecó, SC, 89809-000 (Brazil)

    2015-11-15

    Specialized ceramics are manufactured under special conditions and contain specific elements. They possess unique electrical and thermal properties and are frequently used by the electronics industry. Ceramics containing neodymium-barium-copper (NBC) exhibit high conductivities at low temperatures. NBC-based ceramics are typically combined with oxides, i.e., NBCo produced from neodymium oxide, barium oxide and copper oxide. This study presents NBC ceramics that were produced with barium carbonate, copper oxide and neodymium oxide (NBCa) as starting materials. These ceramics have good electrical conductivities at room temperature. Their conductivities are temperature dependent and related to the starting amount of barium carbonate (w%). - Highlights: • The new crystalline structure were obtained due presence of the barium carbonate. • The NBCa compound has excellent electrical conductivity at room temperature. • The grain crystalline morphology was modified by presence of the barium carbonate. • New Phases α and β were introduced by carbonate barium in the NBC compound.

  17. Performance of cement solidification with barium for high activity liquid waste including sulphate

    International Nuclear Information System (INIS)

    The target liquid waste to be solidified is generated from PWR primary loop spent resin treatment with sulphate acid, so, its main constituent is sodium sulphate and the activity of this liquid is relatively high. Waste form of this liquid waste is considered to be a candidate for the subsurface disposal. The disposed waste including sulphate is anticipated to rise a concentration of sulphate ion in the ground water around the disposal facility and it may cause degradation of materials such as cement and bentonite layer and comprise the disposal facility. There could be two approaches to avoid this problem, the strong design of the disposal facility and the minimization of sulphaste ion migration from the solidified waste. In this study, the latter approach was examined. In order to keep the low concentration of sulphate ion in the ground water, it is effective to make barium sulphate by adding barium compound into the liquid waste in solidification. However, adding equivalent amount of barium compound with sulphate ion causes difficulty of mixing, because production of barium sulphate causes high viscosity. In this study, mixing condition after and before adding cement into the liquid waste was estimated. The mixing condition was set with consideration to keep anion concentration low in the ground water and of mixing easily enough in practical operation. Long term leaching behavior of the simulated solidified waste was also analyzed by PHREEQC. And the concentration of the constitution affected to the disposal facility was estimated be low enough in the ground water. (author)

  18. Suicide with 137 cesium

    International Nuclear Information System (INIS)

    A case report is presented of suicide by radiation exposure after a preceding attempt with potassium ferrocyanide. The subject, a 30-year-old nondestructive-testing technician, held with his right fingers and then placed in his left shirt pocket a metal-canned 5,3-Ci 137Cs source. Despite appearance of signs of severe topical injury by day 3 after the incident and development of systemic toxicity symptoms with indications of affection of internal organs by day 16, medical aid was not sought until day 21 when efforts at management proved unable to prevent fatal outcome. A prominent distinguishing characteristic of this mode of suicide is that the deed's sequelae are delayed in coming into effect. Cases known to have occurred are extremely rare (only two have been described in the literature). This is likely to be related to a distinct unpopularity of radioactive materials as well as their limited availability to the general public. The subjects that did use them were radiation workers having access to such substances; being acquainted with the biological effects of radiation, they, nevertheless, have chosen this protracted and distressful way of taking their lives. (A.B.)

  19. A buffer gas cooled beam of barium monohydride

    Science.gov (United States)

    Iwata, Geoffrey; Tarallo, Marco; Zelevinsky, Tanya

    2016-05-01

    Significant advances in direct laser cooling of diatomic molecules have opened up a wide array of molecular species to precision studies spanning many-body physics, quantum collisions and ultracold dissociation. We present a cryogenic beam source of barium monohydride (BaH), and study laser ablation of solid precursor targets as well as helium buffer gas cooling dynamics. Additionally, we cover progress towards a molecular magneto-optical trap, with spectroscopic studies of relevant cooling transitions in the B2 Σ <--X2 Σ manifold in laser ablated molecules, including resolution of hyperfine structure and precision measurements of the vibrational Frank-Condon factors. Finally, we examine the feasibility of photo dissociation of trapped BaH molecules to yield optically accessible samples of ultracold hydrogen.

  20. Recovery and purification of 4.66 TBq(126 Ci) of {sup 137}Cs from a 20-year-old spent sealed source

    Energy Technology Data Exchange (ETDEWEB)

    Dash, Ashutosh, E-mail: adash@barc.gov.in [Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Varma, R.N. [Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Sastry, K.V.S.; Patil, B.N. [Board of Radiation and Isotope Technology (BRIT), Engineering Programme, Trombay, Mumbai 400085 (India); Ram, Ramu [Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Nikam, Seema [Board of Radiation and Isotope Technology (BRIT), Engineering Programme, Trombay, Mumbai 400085 (India); Venkatesh, Meera [Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2009-09-15

    An attempt to recover and purify 4.66 TBq(126 Ci) of {sup 137}Cs as solution from a 20-year-old doubly encapsulated sealed source containing {sup 137}CsCl was made successfully. The primary capsule was first cut open to retrieve the secondary capsule. The top end of the secondary SS capsule was then cut to render it as an open cylinder and the {sup 137}CsCl pellet inside was dissolved in small aliquots of water. Each aliquot of the {sup 137}CsCl solution was dispensed into glass vials, sealed, assayed and stored. Barium formed during the radioactive decay of {sup 137}Cs was removed by carbonate precipitation. Chloride was removed by heating with HNO{sub 3} and evaporation. About 91.8% of the total activity could be recovered and used subsequently for making brachytherapy sources.

  1. Radioactive Barium Ion Trap Based on Metal-Organic Framework for Efficient and Irreversible Removal of Barium from Nuclear Wastewater.

    Science.gov (United States)

    Peng, Yaguang; Huang, Hongliang; Liu, Dahuan; Zhong, Chongli

    2016-04-01

    Highly efficient and irreversible capture of radioactive barium from aqueous media remains a serious task for nuclear waste disposal and environmental protection. To address this task, here we propose a concept of barium ion trap based on metal-organic framework (MOF) with a strong barium-chelating group (sulfate and sulfonic acid group) in the pore structures of MOFs. The functionalized MOF-based ion traps can remove >90% of the barium within the first 5 min, and the removal efficiency reaches 99% after equilibrium. Remarkably, the sulfate-group-functionalized ion trap demonstrates a high barium uptake capacity of 131.1 mg g(-1), which surpasses most of the reported sorbents and can selectively capture barium from nuclear wastewater, whereas the sulfonic-acid-group-functionalized ion trap exhibits ultrafast kinetics with a kinetic rate constant k2 of 27.77 g mg(-1) min(-1), which is 1-3 orders of magnitude higher than existing sorbents. Both of the two MOF-based ion traps can capture barium irreversibly. Our work proposes a new strategy to design barium adsorbent materials and provides a new perspective for removing radioactive barium and other radionuclides from nuclear wastewater for environment remediation. Besides, the concrete mechanisms of barium-sorbent interactions are also demonstrated in this contribution.

  2. Production of translationally cold barium monohalide ions

    OpenAIRE

    DePalatis, M. V.; Chapman, M.S.

    2013-01-01

    We have produced sympathetically cooled barium monohalide ions BaX$^+$ (X = F, Cl, Br) by reacting trapped, laser cooled Ba$^+$ ions with room temperature gas phase neutral halogen-containing molecules. Reaction rates for two of these (SF$_6$ and CH$_3$Cl) have been measured and are in agreement with classical models. BaX$^+$ ions are promising candidates for cooling to the rovibrational ground state, and our method presents a straightforward way to produce these polar molecular ions.

  3. Chemical abundances and kinematics of barium stars

    CERN Document Server

    de Castro, D B; Roig, F; Jilinski, E; Drake, N A; Chavero, C; Silva, J V Sales

    2016-01-01

    In this paper we present an homogeneous analysis of photospheric abundances based on high-resolution spectroscopy of a sample of 182 barium stars and candidates. We determined atmospheric parameters, spectroscopic distances, stellar masses, ages, luminosities and scale height, radial velocities, abundances of the Na, Al, $alpha$-elements, iron-peak elements, and s-process elements Y, Zr, La, Ce, and Nd. We employed the local-thermodynamic-equilibrium model atmospheres of Kurucz and the spectral analysis code {\\sc moog}. We found that the metallicities, the temperatures and the surface gravities for barium stars can not be represented by a single gaussian distribution. The abundances of $alpha$-elements and iron peak elements are similar to those of field giants with the same metallicity. Sodium presents some degree of enrichment in more evolved stars that could be attributed to the NeNa cycle. As expected, the barium stars show overabundance of the elements created by the s-process. By measuring the mean heav...

  4. Lanthanide doped strontium-barium cesium halide scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Bizarri, Gregory; Bourret-Courchesne, Edith; Derenzo, Stephen E.; Borade, Ramesh B.; Gundiah, Gautam; Yan, Zewu; Hanrahan, Stephen M.; Chaudhry, Anurag; Canning, Andrew

    2015-06-09

    The present invention provides for a composition comprising an inorganic scintillator comprising an optionally lanthanide-doped strontium-barium, optionally cesium, halide, useful for detecting nuclear material.

  5. 137Cs metabolism during pregnancy

    International Nuclear Information System (INIS)

    Data from two pregnant women contaminated with 137 Cs, body burdens of 0.2 and 300 MBq, respectively, at the time of the Goiania accident, were compared. The first one, with lower 137 Cs body burden was exposed during the fourth month of pregnancy, while the second became pregnant three years and eight months after 137 Cs intake. For the first woman 137 Cs concentrations were similar for the mother, infant and placenta, indicating an easy and homogeneous transport of 137 Cs from mother to fetus. The whole-body monitoring data from the second woman, who became pregnant four years after intake, did not show a reduction in biological half-life during the pregnancy. Cs concentration in the mother was found to be 13 times higher than in the infant. One possible reason for this result is that four after intake. Cs is supposed to be concentrated mainly in skeletal muscle tissue. During the pregnancy the blood flux becomes higher in most of organs and tissues except brain, liver and skeletal muscle tissue. In this case, the physiological changes due to pregnancy did not modify the cesium retention. (author)

  6. Europium-doped barium bromide iodide

    Energy Technology Data Exchange (ETDEWEB)

    Gundiah, Gautam; Hanrahan, Stephen M.; Hollander, Fredrick J.; Bourret-Courchesne, Edith D.

    2009-10-21

    Single crystals of Ba0.96Eu0.04BrI (barium europium bromide iodide) were grown by the Bridgman technique. The title compound adopts the ordered PbCl2 structure [Braekken (1932). Z. Kristallogr. 83, 222-282]. All atoms occupy the fourfold special positions (4c, site symmetry m) of the space group Pnma with a statistical distribution of Ba and Eu. They lie on the mirror planes, perpendicular to the b axis at y = +-0.25. Each cation is coordinated by nine anions in a tricapped trigonal prismatic arrangement.

  7. Barium dithionate as an EPR dosemeter.

    Science.gov (United States)

    Baran, M P; Bugay, O A; Kolesnik, S P; Maksimenko, V M; Teslenko, V V; Petrenko, T L; Desrosiers, M F

    2006-01-01

    Electron paramagnetic resonance (EPR) dosimetry is growing in popularity and this success has encouraged the search for other dosimetric materials. Previous studies of gamma-irradiated barium dithionate (BaS(2)O(6) x 2H(2)O) have shown promise for its use as a radiation dosemeter. This work studies in greater detail several essential attributes of the system. Special attention has been directed to the study of EPR response dependences on microwave power, irradiation temperature, minimum detectable dose and post-irradiation stability. PMID:16565205

  8. Scattering lengths of calcium and barium isotopes

    OpenAIRE

    Dammalapati, U.; Willmann, L.; Knoop, S.

    2011-01-01

    We have calculated the s-wave scattering length of all the even isotopes of calcium (Ca) and barium (Ba), in order to investigate the prospect of Bose-Einstein condensation (BEC). For Ca we have used an accurate molecular potential based on detailed spectroscopic data. Our calculations show that Ca does not provide other isotopes alternative to the recently Bose condensed 40Ca that suffers strong losses because of a very large scattering length. For Ba we show by using a model potential that ...

  9. Barium enema findings of milk allergy in infants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Gyoung Ju; Kim, Mi Jeong; Lee, Hee Jung [Keimyung University School of Medicine, Daegu (Korea, Republic of)

    2006-09-15

    We wanted to evaluate the barium enema findings of milk allergy in infants. Retrospective evaluation of the plain abdominal radiography and barium enema findings was performed in fifteen young infants suffering with milk allergy. The presence of gaseous distension, rectal gas, paralytic ileus and mechanical obstruction was evaluated on the plain radiography. The presence of spasm, a transitional zone, a reversed rectosigmoid index and mucosal irregularity was analyzed on the barium enema; the presence of barium retention was also evaluated on 24-hour-delayed plain radiography. Paralytic ileus was the most common finding on the plain radiography (93%). On the barium enema, continuous spasm of the colon, ranging from the rectum to the descending colon, was revealed in ten infants (67%). A transitional zone was observed in one infant and a reversed rectosigmoid index was revealed in four. Mucosal irregularity was observed in two infants. Barium retention was demonstrated in 11 of fifteen cases: throughout the entire colon (n = 3), from the rectum to the descending colon (n = 7), and up to the transverse colon (n = 1). The most common barium enema finding of milk allergy in infants was spasm of the distal colon. The other findings were a transitional zone, a reversed rectosigmoid index, mucosal irregularity and barium retention.

  10. Barium and radium migration in unconsolidated Canadian geological materials

    International Nuclear Information System (INIS)

    This report describes the results of laboratory studies on the distribution coefficients of radium and barium in samples of unconsolidated geologic materials. Graphs of Ksub(d) versus solution concentration for the respective elements showed constant Ksub(d) values in the low concentration range suggesting that, at low concentrations, a distribution coefficient is a valid means of representing the geochemical reactions of both barium and radium. The Ksub(d) values for barium range between 60 and 3500 ml/g. The values appear to be influenced by the amount of barium occurring naturally in the soil materials and thus there is little possiblility of using barium as an analog of radium in laboratory experiments. The Ksub(d) values of radium vary from 50 to 1000 ml/g indicating that a wide range of geological materials have a substantial capacity to retard the migration of radium

  11. Barium appendicitis: A single institution review in Japan

    Science.gov (United States)

    Katagiri, Hideki; Lefor, Alan Kawarai; Kubota, Tadao; Mizokami, Ken

    2016-01-01

    AIM To review clinical experience with barium appendicitis at a single institution. METHODS A retrospective review of patients admitted with a diagnosis of acute appendicitis, from January 1, 2013 to December 31, 2015 was performed. Age, gender, computed tomography (CT) scan findings if available, past history of barium studies, pathology, and the presence of perforation or the development of complications were reviewed. If the CT scan revealed high density material in the appendix, the maximum CT scan radiodensity of the material is measured in Hounsfield units (HU). Barium appendicitis is defined as: (1) patients diagnosed with acute appendicitis; (2) the patient has a history of a prior barium study; and (3) the CT scan shows high density material in the appendix. Patients who meet all three criteria are considered to have barium appendicitis. RESULTS In total, 396 patients were admitted with the diagnosis of acute appendicitis in the study period. Of these, 12 patients (3.0%) met the definition of barium appendicitis. Of these 12 patients, the median CT scan radiodensity of material in the appendix was 10000.8 HU, ranging from 3066 to 23423 HU (± 6288.2). In contrast, the median CT scan radiodensity of fecaliths in the appendix, excluding patients with barium appendicitis, was 393.1 HU, ranging from 98 to 2151 HU (± 382.0). The CT scan radiodensity of material in the appendices of patients with barium appendicitis was significantly higher than in patients with nonbarium fecaliths (P < 0.01). CONCLUSION Barium appendicitis is not rare in Japan. Measurement of the CT scan radiodensity of material in the appendix may differentiate barium appendicitis from routine appendicitis.

  12. Immunotherapy with Agonistic Anti-CD137: Two Sides of a Coin

    Institute of Scientific and Technical Information of China (English)

    YonglianSun; JonathanH.Chen; YangxinFu

    2004-01-01

    CD137 (4-1BB), a member of the TNF receptor superfamily, is an inducible T cell costimulatory receptor primarily expressed on activated CD4+ and CD8+ T cells. Agonistic monoclonal antibodies (mAbs) against CD137 greatly enhance T cell-mediated immune responses against many types of tumors and viruses. Surprisingly, these agonists also showed therapeutic effects in several autoimmune diseases. These findings suggest that in different disease environments, CD137 engagement with agonist mAb in vivo can diametrically modulate immune response outcomes. Therefore, CD137 agonists represent a promising immunotherapeutic approach to a wide array of disparate immune disorders. However, CD137's potency in modulating immune response necessitates caution when targeting CD137 clinically. Cellular & Molecular Immunology. 2004;1(1):31-36.

  13. Immunotherapy with Agonistic Anti-CD137: Two Sides of a Coin

    Institute of Scientific and Technical Information of China (English)

    Yonglian Sun; Jonathan H.Chen; Yangxin Fu

    2004-01-01

    CD137 (4-1BB), a member of the TNF receptor superfamily, is an inducible T cell costimulatory receptor primarily expressed on activated CD4+ and CD8+ T cells. Agonistic monoclonal antibodies (mAbs) against CD137 greatly enhance T cell-mediated immune responses against many types of tumors and viruses. Surprisingly, these agonists also showed therapeutic effects in several autoimmune diseases. These findings suggest that in different disease environments, CD137 engagement with agonist mAb in vivo can diametrically modulate immune response outcomes. Therefore, CD137 agonists represent a promising immunotherapeutic approach to a wide array of disparate immune disorders. However, CD137's potency in modulating immune response necessitates caution when targeting CD137 clinically. Cellular & Molecular Immunology. 2004;1(1):31-36.

  14. High resolution studies of barium Rydberg states

    International Nuclear Information System (INIS)

    The subtle structure of Rydberg states of barium with orbital angular momentum 0, 1, 2 and 3 is investigated. Some aspects of atomic theory for a configuration with two valence electrons are reviewed. The Multi Channel Quantum Defect Theory (MQDT) is concisely introduced as a convenient way to describe interactions between Rydberg series. Three high-resolution UV studies are presented. The first two, presenting results on a transition in indium and europium serve as an illustration of the frequency doubling technique. The third study is of hyperfine structure and isotope shifts in low-lying p states in Sr and Ba. An extensive study of the 6snp and 6snf Rydberg states of barium is presented with particular emphasis on the 6snf states. It is shown that the level structure cannot be fully explained with the model introduced earlier. Rather an effective two-body spin-orbit interaction has to be introduced to account for the observed splittings, illustrating that high resolution studies on Rydberg states offer an unique opportunity to determine the importance of such effects. Finally, the 6sns and 6snd series are considered. The hyperfine induced isotope shift in the simple excitation spectra to 6sns 1S0 is discussed and attention is paid to series perturbers. It is shown that level mixing parameters can easily be extracted from the experimental data. (Auth.)

  15. NANOSCALE BARIUM HYDROSILICATES: CHOOSING THE SYNTHESIS TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    GRISHINA Anna Nikolaevna

    2013-08-01

    Full Text Available Cement concretes are the most used materials in modern civil engineering. Due to that such materials draw great attention both in the Russian Federation and abroad. The possibility to enhance the manufacturability and operational properties of concretes results in significant reduction of overall operating costs. Many enhancement methods have been elaborated. Among them there is one based on introduction of calcium hydrosilicates into construction composition. The authors set up a hypothesis that similarity between properties and structures of different hydrosilicates (for example, alkaline earth metals and metals of the second group will provide similar increased operational characteristics. The specialists of Research and Educational Center «Nanotechnology» are developing cement composites nanomodification methods which include introduction of nanodimensional barium hydrosilicates particles. The synthesis of barium hydrosilicates particles can be done with the use of many technologies, different by energy consumption or performing complexity. Taking into account both these factors, one can assume that low-temperature sol-gel synthesis from diluted water solutions is the proper technology. The present paper shows that this assumption is correct. The selection of certain technology is made by the means of multiobjective optimization, which is in turn is performed by the means of linear scalarization. This method, while not always giving the Pareto optimal solutions, can be easily implemented. The particle size distribution is taken into consideration during selection of objectives and weights. It is shown that selected technology allows manufacturing nanoparticles with median size about 30 nm.

  16. The Novel Formation of Barium Titanate Nanodendrites

    Directory of Open Access Journals (Sweden)

    Chien-Jung Huang

    2014-01-01

    Full Text Available The barium titanate (BaTiO3 nanoparticles with novel dendrite-like structures have been successfully fabricated via a simple coprecipitation method, the so-called BaTiO3 nanodendrites (BTNDs. This method was remarkable, fast, simple, and scalable. The growth solution is prepared by barium chloride (BaCl2, titanium tetrachloride (TiCl4, and oxalic acid. The shape and size of BaTiO3 depend on the amount of added BaCl2 solvent. To investigate the influence of amount of BaCl2 on BTNDs, the amount of BaCl2 was varied in the range from 3 to 6 mL. The role of BaCl2 is found to have remarkable influence on the morphology, crystallite size, and formation of dendrite-like structures. The thickness and length of the central stem of BTND were ~300 nm and ~20 μm, respectively. The branchings were found to occur at irregular intervals along the main stem. Besides, the formation mechanism of BTND is proposed and discussed.

  17. Coprecipitation of europium with barium sulphate

    International Nuclear Information System (INIS)

    The distribution behaviour of the trivalent europium ion at a micro-component scale, between barium sulphate and aqueous solution, was studied at ambient temperature. Experiments were carried out using radioactive tracers. Results indicate an enrichment of the micro component in the solid phase relative to the solution. The effects of the concentrations of the micro and macro-elements on the coprecipitation have been examined. Europium distribution coefficient DEu increases from 1.1 ± 0.2 to 3.2 ± 0.4 when initial europium concentration decreases from more than 17 x 10-5 to 1.4 x 10-5 M, in sulphuric media with SO42- in excess or CBa2+/CSO42- Eu. The coprecipitation of europium with barium sulphate as a heterovalent solid-solution is described by heterogeneous model obeying the Doerner and Hoskins logarithmic partition law. The weaker partition coefficients lower than unity (λ = 0.25 when CEu(III) ∼ 1.4 x 10-5 M and λ = 0.13 when CBa2+/CSO42- -5 ≤ CEu(III) = 153.5 x 10-5 M) lead to crystals increasingly enriched in the trace element. (orig.)

  18. Strengthening mechanism of steels treated by barium-bearing alloys

    Institute of Scientific and Technical Information of China (English)

    Zhouhua Jiang; Yang Liu

    2008-01-01

    The deoxidation, desulfurization, dephosphorization, microstructure, and mechanical properties of steels treated by barium-bearing alloys were investigated in laboratory and by industrial tests. The results show that barium takes part in the deoxidation reaction at the beginning of the experiments, generating oxide and sulfide compound inclusions, which easily float up from the molten steel, leading to the rapid reduction of total oxygen content to a very low level. The desulfurization and dephosphorization capabilities of calcium-bearing alloys increase with the addition of barium. The results of OM and SEM observations and mechanical property tests show that the structure of the steel treated by barium-bearing alloys is refined remarkably, the iamellar thickness of pearlitic structure decreases, and the pearlitic morphology shows clustering distribution. Less barium exists in steel substrate and the enrichment of barium-bearing precipitated phase mostly occurs in grain boundary and phase boundary, which can prevent the movement of grain boundary and dislocation during the heat treatment and the deformation processes. Therefore, the strength and toughness of barium-treated steels are improved by the effect of grain-boundary strengthening and nail-prick dislocation.

  19. Designed microstructures in textured barium hexaferrite

    Science.gov (United States)

    Hovis, David Brian

    It is a fundamental principle of materials science that the microstructure of a material defines its properties and ultimately its performance for a given application. A prime example of this can be found in the large conch shell Strombus gigas, which has an intricate microstructure extending across five distinct length scales. This microstructure gives extraordinary damage tolerance to the shell. The structure of Strombus gigas cannot be replicated in a modern engineering ceramic with any existing processing technique, so new processing techniques must be developed to apply this structure to a model material. Barium hexaferrite was chosen as a model material to create microstructures reminiscent of Strombus gigas and evaluate its structure-property relations. This work describes novel processing methods to produce textured barium hexaferrite with no coupling between the sample geometry and the texture direction. This technique, combining magnetic field-assisted gelcasting with templated grain growth, also allows multilayer samples to be fabricated with different texture directions in adjacent layers. The effects of adding either B2O3 or excess BaCO 3 on the densification and grain growth of barium hexaferrite was studied. The texture produced using this technique was assessed using orientation imaging microscopy (OIM) at Oak Ridge National Laboratory. These measurements showed peak textures as high as 60 MRD and sharp interfaces between layers cast with different texture directions. The effect of oxygen on the quality of gelcasting is also discussed, and it is shown that with proper mold design, it is possible to gelcast multiple layers with differing texture directions without delamination. Monolithic and multilayer samples were produced and tested in four point bending to measure the strength and work of fracture. Modulus measurements, made with the ultrasonic pulse-echo technique, show clear signs of microcracking in both the isotropic and textured samples

  20. Cesium-137, a drama recounted; Cesio-137, um drama recontado

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Suzane de Alencar

    2013-01-15

    The radiological accident with Cesium-137, which started on Goiania in 1987, did not stop with the end of radiological contamination and continues in a judicial, scientific and narrative process of identification and recognition of new victims. The drama occupies a central place on the dynamics of radiological event, as it extends its limits, inflects its intensity and updates the event. As a narrative of the event, the ethnography incorporates and brings up to date the drama as an analysis landmark and the description of the theme as it is absorbed by a dramatic process. Cesium-137, a drama recounted is a textual experimentation based on real events and characters picked out from statements reported in various narratives about the radiological accident. (author)

  1. Chemical composition of Eu2+ luminescence in the barium hexaaluminates

    International Nuclear Information System (INIS)

    This paper consists of two parts. In the first part the chemical composition of two kinds of barium hexaaluminate (one poor and one rich in barium) is explained using the local electroneutrality concept. In the second part a reinvestigation of the Eu2+ luminescence in these compounds is reported. The emission spectrum of each of the two compounds shows a blue and a green emission bank. The blue emission bank is ascribed to Eu2+ ions at barium sites, whereas the green emission band is identified with Eu2+ ions incorporated at aluminum sites within spinel blocks of the structure

  2. Barium concentration in grain of Aegilops and Triticum species

    Directory of Open Access Journals (Sweden)

    Denčić Srbislav S.

    2015-01-01

    Full Text Available The aim of this study was to evaluate the concentration of barium in grain of various Aegilops and Triticum species with different genomes. The studied species differed significantly with respect to the concentration of barium. The grain of wild diploid Aegilops speltoides, the donor of B genome, contained significantly higher Ba concentration than all other analyzed genotypes. Wild and cultivated tetraploid wheats (Triticum diciccoides, Triticum dicoccon, Triticum turgidum and Triticum durum had the lowest Ba concentration in grain. The modern cultivated hexaploid varieties presented substantial variation in grain concentration of barium. The highest Ba concentration (3.42 mg/kg occurred in Serbian winter wheat variety Panonnia.

  3. Structure of barium sodium trimetaphosphate trihydrate

    Energy Technology Data Exchange (ETDEWEB)

    Averbuch-Pouchot, M.T.; Durif, A.

    1987-03-15

    BaNaP/sub 3/O/sub 9/ . 3H/sub 2/O, M/sub r/=451.29, triclinic, Panti 1, a=7.067(3), b=9.071(3), c=9.906(4) A, ..cap alpha..=116.46(5), ..beta..=95.97(5), ..gamma..=74.03(5)/sup 0/, V=546.4 A/sup 3/, Z=2, D/sub m/ not measured, D/sub x/=2.743 Mg m/sup -3/, lambda(Mo K..cap alpha..)=0.7107 A, ..mu..=4.28 mm/sup -1/, F(000)=428, T=293 K, R=0.028 for 3775 independent reflexions. The P/sub 3/O/sub 9/ ring anions and the water molecules build up a three-dimensional network through hydrogen bonds. Inside this network barium and sodium have respectively nine- and sevenfold coordinations.

  4. Chemical abundance analysis of 19 barium stars

    CERN Document Server

    Yang, G C; Spite, M; Chen, Y Q; Zhao, G; Zhang, B; Liu, G Q; Liu, Y J; Liu, N; Deng, L C; Spite, F; Hill, V; Zhang, C X

    2016-01-01

    We aim at deriving accurate atmospheric parameters and chemical abundances of 19 barium (Ba) stars, including both strong and mild Ba stars, based on the high signal-to-noise ratio and high resolution Echelle spectra obtained from the 2.16 m telescope at Xinglong station of National Astronomical Observatories, Chinese Academy of Sciences. The chemical abundances of the sample stars were obtained from an LTE, plane-parallel and line-blanketed atmospheric model by inputting the atmospheric parameters (effective temperatures, surface gravities, metallicity and microturbulent velocity) and equivalent widths of stellar absorption lines. These samples of Ba stars are giants indicated by atmospheric parameters, metallicities and kinematic analysis about UVW velocity. Chemical abundances of 17 elements were obtained for these Ba stars. Their light elements (O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn and Ni) are similar to the solar abundances. Our samples of Ba stars show obvious overabundances of neutron-capture (n-ca...

  5. A novel barium polymeric membrane sensor for selective determination of barium and sulphate ions based on the complex ion associate barium(II)-Rose Bengal as neutral ionophore

    Energy Technology Data Exchange (ETDEWEB)

    Othman, A.M. [Genetic Engineering and Biotechnology Research Institute (GEBRI), Minufiya University, Sadat City (Egypt); El-Shahawi, M.S. [Chemistry Department, Faculty of Science at Damiatta, Mansoura University, Damiatta, Dumyat 34517 (Egypt)]. E-mail: mohammad_el_shahawi@yahoo.co.uk; Abdel-Azeem, M. [Chemistry Department, Faculty of Science at Damiatta, Mansoura University, Damiatta, Dumyat 34517 (Egypt)

    2006-01-12

    A simple, long life, rapid response and sensitive barium(II)-PVC membrane sensor that typically follows Nernstian behavior has been developed for the assay of barium(II) ions. The developed sensor has been made by incorporating the complex ion associate of barium(II)-Rose Bengal (Ba-RB) as an ionophore into a plasticized PVC matrix. The sensor is stable and exhibited fast potential response of 20 s and gave a good linear response with a Nernstian slope of 28.5 {+-} 0.4 mV/decade of activity within the concentration range 5 x 10{sup -5} to 10{sup -1} M over a wide range of pH 4.5-10.0 for barium(II) ions. The developed sensor showed comparatively good selectivity for barium(II) ions with respect to other alkali, alkaline earth, transition and heavy metal ions. The plasticizer o-nitrophenyloctyl ether controlled significantly the calibration slope and the lifetime of the fabricated sensor. The proposed sensor was used successfully for the analysis of barium(II) ions in wastewater samples and in lithophone pigment with excellent recovery percentages in the range 98.9-99.8 {+-} 1.6%. The determination of sulphate in fresh and potable water samples with the developed sensor has been also achieved successfully. The described sensor provides a reliable means with good correlation with the data obtained by atomic absorption spectrometry (AAS) and other spectrophotometric methods for the analysis of trace amounts of barium(II) and/or sulphate ions in different matrices.

  6. A novel barium polymeric membrane sensor for selective determination of barium and sulphate ions based on the complex ion associate barium(II)-Rose Bengal as neutral ionophore

    International Nuclear Information System (INIS)

    A simple, long life, rapid response and sensitive barium(II)-PVC membrane sensor that typically follows Nernstian behavior has been developed for the assay of barium(II) ions. The developed sensor has been made by incorporating the complex ion associate of barium(II)-Rose Bengal (Ba-RB) as an ionophore into a plasticized PVC matrix. The sensor is stable and exhibited fast potential response of 20 s and gave a good linear response with a Nernstian slope of 28.5 ± 0.4 mV/decade of activity within the concentration range 5 x 10-5 to 10-1 M over a wide range of pH 4.5-10.0 for barium(II) ions. The developed sensor showed comparatively good selectivity for barium(II) ions with respect to other alkali, alkaline earth, transition and heavy metal ions. The plasticizer o-nitrophenyloctyl ether controlled significantly the calibration slope and the lifetime of the fabricated sensor. The proposed sensor was used successfully for the analysis of barium(II) ions in wastewater samples and in lithophone pigment with excellent recovery percentages in the range 98.9-99.8 ± 1.6%. The determination of sulphate in fresh and potable water samples with the developed sensor has been also achieved successfully. The described sensor provides a reliable means with good correlation with the data obtained by atomic absorption spectrometry (AAS) and other spectrophotometric methods for the analysis of trace amounts of barium(II) and/or sulphate ions in different matrices

  7. 49 CFR 176.137 - Portable magazine.

    Science.gov (United States)

    2010-10-01

    ... type 3 magazine under 27 CFR part 55 subpart K may be used for the stowage of Class 1 (explosive... 49 Transportation 2 2010-10-01 2010-10-01 false Portable magazine. 176.137 Section 176.137... Requirements for Class 1 (Explosive) Materials Stowage § 176.137 Portable magazine. (a) Each portable...

  8. 21 CFR 137.190 - Cracked wheat.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Cracked wheat. 137.190 Section 137.190 Food and... Related Products § 137.190 Cracked wheat. Cracked wheat is the food prepared by so cracking or cutting into angular fragments cleaned wheat other than durum wheat and red durum wheat that, when tested...

  9. 21 CFR 137.195 - Crushed wheat.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Crushed wheat. 137.195 Section 137.195 Food and... Related Products § 137.195 Crushed wheat. Crushed wheat, coarse ground wheat, is the food prepared by so crushing cleaned wheat other than durum wheat and red durum wheat that, when tested by the...

  10. 21 CFR 137.350 - Enriched rice.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Enriched rice. 137.350 Section 137.350 Food and... Related Products § 137.350 Enriched rice. (a) The foods for which definitions and standards of identity are prescribed by this section are forms of milled rice (except rice coated with talc and glucose...

  11. 5 CFR 185.137 - Initial decision.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Initial decision. 185.137 Section 185.137 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PROGRAM FRAUD CIVIL REMEDIES § 185.137 Initial decision. (a) The ALJ shall issue an initial decision based only on the record,...

  12. 14 CFR 125.137 - Oil valves.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Oil valves. 125.137 Section 125.137....137 Oil valves. (a) Each oil valve must— (1) Comply with § 125.155; (2) Have positive stops or... the valve. (b) The closing of an oil shutoff means must not prevent feathering the propeller,...

  13. 7 CFR 58.137 - Excluded milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Excluded milk. 58.137 Section 58.137 Agriculture... Milk § 58.137 Excluded milk. A plant shall not accept milk from a producer if: (a) The milk has been in...) Three of the last five milk samples have exceeded the maximum bacterial estimate of 500,000 per...

  14. 25 CFR 137.6 - Power development.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Power development. 137.6 Section 137.6 Indians BUREAU OF... CARLOS INDIAN IRRIGATION PROJECT, ARIZONA § 137.6 Power development. The cost of the power development at... power development shall be disposed of as required by the terms and conditions of the act of March...

  15. 25 CFR 137.1 - Water supply.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Water supply. 137.1 Section 137.1 Indians BUREAU OF... CARLOS INDIAN IRRIGATION PROJECT, ARIZONA § 137.1 Water supply. The engineering report dealt with in... capacity of the San Carlos reservoir created by the Coolidge Dam and the water supply therefor over...

  16. 45 CFR 96.137 - Payment schedule.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Payment schedule. 96.137 Section 96.137 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION BLOCK GRANTS Substance Abuse Prevention and Treatment Block Grant § 96.137 Payment schedule. (a) The Block Grant money that may be...

  17. 21 CFR 211.137 - Expiration dating.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Expiration dating. 211.137 Section 211.137 Food... § 211.137 Expiration dating. (a) To assure that a drug product meets applicable standards of identity, strength, quality, and purity at the time of use, it shall bear an expiration date determined...

  18. The Karlsruhe 4π barium fluoride detector

    International Nuclear Information System (INIS)

    A new experimental approach has been implemented for accurate measurements of neutron capture cross sections in the energy range from 5 to 200 keV. The Karlsruhe 4π Barium Fluoride Detector consists of 42 crystals shaped as hexagonal and pentagonal truncated pyramids forming a spherical shell with 10 cm inner radius and 15 cm thickness. All crystals are supplied with reflector and photomultiplier, thus representing independent gamma-ray detectors. Each detector module covers the same solid angle with respect to a gamma-ray source located in the centre. The energy resolution of the 4π detector is 14% at 662 keV and 7% at 2.5 MeV gamma-ray energy, the overall time reslution is 500 ps and the peak efficiency 90% at 1 MeV. The detector allows to register capture cascades with 95% probability above a threshold energy of 2.5 MeV in the sum energy spectrum. Neutrons are produced via the 7Li(p,n)7Be reaction using the pulsed proton beam of a Van de Graaff accelerator. The neutron spectrum can be taylored according to the experimental requirements in an energy range from 5 to 200 keV by choosing appropriate proton energies. A collimated neutron beam is passing through the detector and hits the sample in the centre. The energy of captured neutrons is determined via time of flight, the primary flight path being 77 cm. The combination of short primary flight path, a 10 cm inner radius of the spherical BaF2 shell, and the low capture cross section of barium allows to discriminate background due to capture of sample scattered neutrons in the scintillator by time of flight, leaving part of the neutron energy range completely undisturbed. (orig./HSI)

  19. Experimental determination of barium isotope fractionation during diffusion and adsorption processes at low temperatures

    Science.gov (United States)

    van Zuilen, Kirsten; Müller, Thomas; Nägler, Thomas F.; Dietzel, Martin; Küsters, Tim

    2016-08-01

    Variations in barium (Ba) stable isotope abundances measured in low and high temperature environments have recently received increasing attention. The actual processes controlling Ba isotope fractionation, however, remain mostly elusive. In this study, we present the first experimental approach to quantify the contribution of diffusion and adsorption on mass-dependent Ba isotope fractionation during transport of aqueous Ba2+ ions through a porous medium. Experiments have been carried out in which a BaCl2 solution of known isotopic composition diffused through u-shaped glass tubes filled with silica hydrogel at 10 °C and 25 °C for up to 201 days. The diffused Ba was highly fractionated by up to -2.15‰ in δ137/134Ba, despite the low relative difference in atomic mass. The time-dependent isotope fractionation can be successfully reproduced by a diffusive transport model accounting for mass-dependent differences in the effective diffusivities of the Ba isotope species (D137Ba /D134Ba =(m134 /m137) β). Values of β extracted from the transport model were in the range of 0.010-0.011. Independently conducted batch experiments revealed that adsorption of Ba onto the surface of silica hydrogel favoured the heavier Ba isotopes (α = 1.00015 ± 0.00008). The contribution of adsorption on the overall isotope fractionation in the diffusion experiments, however, was found to be small. Our results contribute to the understanding of Ba isotope fractionation processes, which is crucial for interpreting natural isotope variations and the assessment of Ba isotope ratios as geochemical proxies.

  20. Determination of {sup 135}Cs and {sup 137}Cs in environmental samples: A review

    Energy Technology Data Exchange (ETDEWEB)

    Russell, B.C., E-mail: ben.russell@npl.co.uk [GAU-Radioanalytical, Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH (United Kingdom); National Physical Laboratory, Hampton Road, Teddington, Middlesex, TW11 0LW (United Kingdom); Croudace, Ian W.; Warwick, Phil E. [GAU-Radioanalytical, Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH (United Kingdom)

    2015-08-26

    Radionuclides of caesium are environmentally important since they are formed as significant high yield fission products ({sup 135}Cs and {sup 137}Cs) and activation products ({sup 134}Cs and {sup 136}Cs) during nuclear fission. They originate from a range of nuclear activities such as weapons testing, nuclear reprocessing and nuclear fuel cycle discharges and nuclear accidents. Whilst {sup 137}Cs, {sup 134}Cs and {sup 136}Cs are routinely measurable at high sensitivity by gamma spectrometry, routine detection of long-lived {sup 135}Cs by radiometric methods is challenging. This measurement is, however, important given its significance in long-term nuclear waste storage and disposal. Furthermore, the {sup 135}Cs/{sup 137}Cs ratio varies with reactor, weapon and fuel type, and accurate measurement of this ratio can therefore be used as a forensic tool in identifying the source(s) of nuclear contamination. The shorter-lived activation products {sup 134}Cs and {sup 136}Cs have a limited application but provide useful early information on fuel irradiation history and have importance in health physics. Detection of {sup 135}Cs (and {sup 137}Cs) is achievable by mass spectrometric techniques; most commonly inductively coupled plasma mass spectrometry (ICP-MS), as well as thermal ionisation (TIMS), accelerator (AMS) and resonance ionisation (RIMS) techniques. The critical issues affecting the accuracy and detection limits achievable by this technique are effective removal of barium to eliminate isobaric interferences arising from {sup 135}Ba and {sup 137}Ba, and elimination of peak tailing of stable {sup 133}Cs on {sup 135}Cs. Isobaric interferences can be removed by chemical separation, most commonly ion exchange chromatography, and/or instrumental separation using an ICP-MS equipped with a reaction cell. The removal of the peak tailing interference is dependent on the instrument used for final measurement. This review summarizes and compares the analytical procedures

  1. A NOVEL HYDROTHERMAL SYNTHESIS METHOD FOR BARIUM FERRITE

    Institute of Scientific and Technical Information of China (English)

    Kang Li; Hongchen Gu; Qun Wei

    2004-01-01

    In the present work, fine barium ferrite powder has been synthesized through a one-step hydrothermal process in an autoclave at [OH-]/[Cl-] ratio of 2:1 in the temperature range from 180 to 260 ℃ using barium chloride (BaCl2), ferrous chloride (FeCl2) and potassium nitrate (KNO3) as the starting materials. Both particle size and saturation magnetization (Ms) increase with increasing hydrothermal reaction temperature, while the intrinsic coercivity (iHc) peaks at 685 Oe at 230 ℃. Morphology progress from the barium ferrite precursor particles to the barium hexaferrite particles has been monitored with increasing hydrothermal reaction time at 230 ℃ in the autoclave.

  2. Upper gastrointestinal barium evaluation of duodenal pathology: A pictorial review

    Institute of Scientific and Technical Information of China (English)

    Pankaj; Gupta; Uma; Debi; Saroj; Kant; Sinha; Kaushal; Kishor

    2014-01-01

    Like other parts of the gastrointestinal tract(GIT), duodenum is subject to a variety of lesions both congenital and acquired. However, unlike other parts of the GIT viz. esophagus, rest of the small intestine and large intestine, barium evaluation of duodenal lesions is technically more challenging and hence not frequently reported. With significant advances in computed tomography technology, a thorough evaluation including intraluminal, mural and extramural is feasible in a single non-invasive examination. Notwithstanding, barium evaluation still remains the initial and sometimes the only imaging study in several parts of the world. Hence,a thorough acquaintance with the morphology of various duodenal lesions on upper gastrointestinal barium examination is essential in guiding further evaluation. We reviewed our experience with various common and uncommon barium findings in duodenal abnormalities.

  3. Liquid-phase-deposited barium titanate thin films on silicon

    International Nuclear Information System (INIS)

    Using a mixture of hexafluorotitanic acid, barium nitrate and boric acid, high refractive index (1.54) barium titanate films can be deposited on silicon substrates. The deposited barium titanate films have featureless surfaces. The deposition temperature is near room temperature (800C). However, there are many fluorine and silicon incorporations in the films. The refractive index of the as-deposited film is 1.54. By current-voltage measurement, the leakage current of the as-deposited film with a thickness of 1000 A is about 9.48x10-7 A cm-2 at the electrical field intensity of 0.3 MV cm-1. By capacitance-voltage measurement, the effective oxide charge of the liquid-phase-deposited barium titanate film is 3.06x1011 cm-2 and the static dielectric constant is about 22. (author)

  4. Peritonite por bário Barium peritonitis

    Directory of Open Access Journals (Sweden)

    Gerson Alves Pereira Júnior

    1999-10-01

    Full Text Available We report a case of a 49 years-old man who underwent a barium meal examination for an epigastric pain. A perforated gastric ulcer with barium extravasation into peritoneal cavity was seen on X-rays. During an emergency laparotomy, a perforated pyloric ulcer was noted, along with barium contamination in the peritoneal cavity. The ulcer was closed with an omental patch and an extensive peritoneal lavage with saline was performed. During the postoperative period, the patient developed signs of peritonitis and underwent a new laparotomy was at the 9th day showing a subfrenic abscess with a large barium contamination. The patient presented septic shock and multiple organ failure. dying on the 21th day.

  5. Electrorheological behavior of rare earth-doped barium titanate suspensions

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Doping Y, La, Ce into barium titanate is found to be able to improve its electrorheological (ER) effect in DC electrical field. The yield stress of a typical doped barium titanate/silicone oil suspension is approximately 3.2 -*7〗kPa at 3.5 -*7〗kV/mm, which is 10 times larger than that of pure barium titanate/silicone oil suspensions. The ER effect increases with the decrease of ionic radius of rare earth (RE) dopant when RE concentration remains constant, and the suspensions exhibit a relatively high shear stress when Y, La, Ce mole fractions are 15%, 10%~15%, and 5%, respectively. Dielectric measurements show that the suitable doping with RE element increases dielectric loss of barium titanate and causes very marked dielectric relaxation at low frequency. By measuring X-ray diffraction patterns of doped barium titanate, it is considered that the occurrence of lattice distortion or defects may be responsible for the change of dielectric properties which results in the improvement of ER effect of barium titanate in DC electrical field.

  6. Lifetime Measurement for 6snp Rydberg States of Barium

    Institute of Scientific and Technical Information of China (English)

    SHEN Li; WANG Lei; YANG Hai-Feng; LIU Xiao-Jun; LIU Hong-Ping

    2011-01-01

    @@ We present a simple and efficient method for measuring the atomic lifetimes in order of tens of microseconds and demonstrate it in the lifetime determination of barium Rydberg states.This method extracts the lifetime information from the time-of-flight spectrum directly, which is much more efficient than other methods such as the time-delayed field ionization and the traditional laser induced fluorescence.The lifetimes determined with our method for barium Rydberg 6snp(n=37-59)series are well coincident with the values deduced from the absolute oscillator strengths of barium which were given in the literature [J.Phys.B 14(1981)4489, 29(1996)655]on experiments.%We present a simple and efficient method for measuring the atomic lifetimes in order of tens of microseconds and demonstrate it in the lifetime determination of barium Rydberg states. This method extracts the lifetime information from the time-of-flight spectrum directly, which is much more efficient than other methods such as the time-delayed field ionization and the traditional laser induced fluorescence. The lifetimes determined with our method for barium Rydberg 6snp (n=37-59) series are well coincident with the values deduced from the absolute oscillator strengths of barium which were given in the literature [J. Phys. B 14 (1981) 4489, 29 (1996) 655] onexperiments.

  7. Investigation of neutron-deficient isotopes in the barium-region

    International Nuclear Information System (INIS)

    Bombarding targets of 106Cd, 108Cd and 110Cd with 16O ions of 52.5-66.0 MeV neutron deficient barium, cesium and xenon isotopes were produced and have been studied using excitation functions and neutron-gamma, proton-gamma, alpha-gamma and gamma-gamma coincidence measurements. Partial level schemes for 123Ba and 121Ba were proposed. A number of gamma transitions was assigned to the different product nuclei. The measured particle emission probabilities from the compound nuclei are compared with different evaporation models. The models mostly underestimate neutron emission and often overestimate the emission of alpha particles. (orig.)

  8. Capacitively coupled electrolyte-conductivity sensor based on high-k material of barium strontium titanate

    OpenAIRE

    Huck, C.; Poghossian, A; Baecker, M; Chaudhuri, S.; Zander, W; Schubert, J.; Begoyan, V. K.; Buniatyan, V. V.; Wagner, Patrick Hermann; Schoening, M. J

    2014-01-01

    A miniaturized capacitively coupled contactless conductivity detection (C4D) sensor based on high-kperovskite oxide of barium strontium titanate (BST) has been implemented for the first time. The BST films(∼120 nm thick) of Ba0.25Sr0.75TiO3composition were prepared on a p-Si-SiO2-Pt structure by pulsed laserdeposition technique using BST targets fabricated by the self-propagating high-temperature synthesismethod. The Pt electrodes were buried into the SiO2layer to obtain a planar structure. F...

  9. Hanford Isotope Project strategic business analysis Cesium-137 (Cs-137)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    The purpose of this business analysis is to address the beneficial reuse of Cesium 137 (Cs-137) in order to utilize a valuable national asset and possibly save millions of tax dollars. Food irradiation is the front runner application along with other uses. This business analysis supports the objectives of the Department of Energy National Isotope Strategy distributed in August 1994 which describes the DOE plans for the production and distribution of isotope products and services. As part of the Department`s mission as stated in that document. ``The Department of Energy will also continue to produce and distribute other radioisotopes and enriched stable isotopes for medical diagnostics and therapeutics, industrial, agricultural, and other useful applications on a businesslike basis. This is consistent with the goals and objectives of the National Performance Review. The Department will endeavor to look at opportunities for private sector to co-fund or invest in new ventures. Also, the Department will seek to divest from ventures that can more profitably or reliably be operated by the private sector.``

  10. Hanford Isotope Project strategic business analysis Cesium-137 (Cs-137)

    International Nuclear Information System (INIS)

    The purpose of this business analysis is to address the beneficial reuse of Cesium 137 (Cs-137) in order to utilize a valuable national asset and possibly save millions of tax dollars. Food irradiation is the front runner application along with other uses. This business analysis supports the objectives of the Department of Energy National Isotope Strategy distributed in August 1994 which describes the DOE plans for the production and distribution of isotope products and services. As part of the Department's mission as stated in that document. ''The Department of Energy will also continue to produce and distribute other radioisotopes and enriched stable isotopes for medical diagnostics and therapeutics, industrial, agricultural, and other useful applications on a businesslike basis. This is consistent with the goals and objectives of the National Performance Review. The Department will endeavor to look at opportunities for private sector to co-fund or invest in new ventures. Also, the Department will seek to divest from ventures that can more profitably or reliably be operated by the private sector.''

  11. Mars at Ls 137o

    Science.gov (United States)

    2006-01-01

    13 November 2006 These images capture what Mars typically looks like in mid-afternoon at Ls 137o. In other words, with the exception of occasional differences in weather and polar frost patterns, this is what the red planet looks like this month (November 2006). Six views are shown, including the two polar regions. These are composites of 24-26 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global mapping images acquired at red and blue wavelengths. The 'hole' over the south pole is an area where no images were obtained, because this polar region is enveloped in wintertime darkness. Presently, it is summer in the northern hemisphere and winter in the southern hemisphere. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn. Northern summer/southern winter begins at Ls 90o, northern autumn/southern spring start at Ls 180o, and northern winter/southern summer begin at Ls 270o. Ls 137o occurs in the middle of this month (November 2006). The pictures show how Mars appeared to the MOC wide angle cameras at a previous Ls 137o in March 2001. The six views are centered on the Tharsis region (upper left), Acidalia and Mare Eyrthraeum (upper right), Syrtis Major and Hellas (middle left), Elysium and Mare Cimmeria (middle right), the north pole (lower left), and the south pole (lower right).

  12. Leachability of barium-radium sulphate sludges

    International Nuclear Information System (INIS)

    This paper presents results from the first phase of a research program designed to examine the leachability of radium-226 from barium-radium sulphate sludges. Batch leaching tests were performed. Results showed that liquid:solid contact time was relatively unimportant; radium in the sludge was stable in the presence of deionized water with a slight increase in the amount leached per gram of sludge occurring at higher liquid:solid ratios. Not unexpectedly, low and high values of leachant pH increased radium leaching. Both monovalent and divalent salt solutions also increased leaching; however, dissolved radium-226 activity levels in the leachate decreased as leachant molarity increased. For divalent salts this can be explained by the common ion effect; for monovalent salts it is opposite to results expected from solubility considerations. The interpretation of all results is complicated by the fact that in most tests, the amount of radium-226 present in the leachate was lower than the calculated contribution from the mother liquour present with the sludge. This apparent ability of the sludge to absorb radium from solution may be related to dissolution and reprecipitation of the sludge during the leaching tests

  13. The diagnostic value of barium enema in acute appendicitis

    International Nuclear Information System (INIS)

    Acute appendicitis is the most common acute surgical condition of the abdomen. When the clinical presentation is atypical, barium enema has proven to be safe and useful in confirming the diagnosis and reducing the negative surgical exploration. However, the performance of barium enema in acute appendicitis has known contraindication primarily because of fear of leakage by perforation of the inflamed appendix. This study using barium enema as a diagnostic aid in acute appendicitis with atypical clinical presentation was performed to further support the previously noted efficacy and safety of this procedure. The results were as followings: 1. In case of acute appendicitis with atypical clinical presentation, the use of barium enema as a diagnostic aid increased the accuracy of diagnosis and decreased the negative surgical exploration. In women between 11 to 50 years old age, especially, it played important role differentiating appendicitis from nonsurgical acute abdomen. 2. The results of the study were 92.31% in sensitivity, 7.69% in false positive, 6.9% in false negative, and 10.26% in negative appendectomy. 3. None of case of leakage of barium by perforation of the inflamed appendix was noted, therefore, barium enema was thought to be safe as a diagnostic aid in acute appendicitis. 4. A simple partial or non filling of appendix without other associated positive finding could not exclude appendicitis, therefore, close clinical observation was necessary. 5. The positive findings of barium enema and their sensitivity were as followings: 1. Non filling of appendix: 90% 2. Partial filling of appendix: 91.7% 3. Displacement or a local impression on terminal ileum: 100%

  14. Dicty_cDB: SLA137 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SL (Link to library) SLA137 (Link to dictyBase) - - - Contig-U16449-1 SLA137Z (Link... to Original site) - - SLA137Z 491 - - - - Show SLA137 Library SL (Link to library) Clone ID SLA137 (Link to...ycdb.biol.tsukuba.ac.jp/CSM/SL/SLA1-B/SLA137Q.Seq.d/ Representative seq. ID SLA13...7Z (Link to Original site) Representative DNA sequence >SLA137 (SLA137Q) /CSM/SL/SLA1-B/SLA137Q.Seq.d/ XXXXX...ATAAAAAAAAAAAAAAAA sequence update 1997. 5. 8 Translated Amino Acid sequence ---AWVDENGGGTMIPVSVSFEKALLDLSSD

  15. Dicty_cDB: VSI137 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VS (Link to library) VSI137 (Link to dictyBase) - - - - VSI137P (Link to Original site) VSI137F 60 VSI...dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig - Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VS/VSI...1-B/VSI137Q.Seq.d/ Representative seq. ID VSI137P (Link to Original si...flsnhfkkk--- ---ymq Homology vs CSM-cDNA Score E Sequences producing significant alignments: (bits) Value VSI137 (VSI...137Z 12 VSI137P 72 - - Show VSI137 Library VS (Link to library) Clone ID VSI137 (Link to

  16. A direct molecular link between the autism candidate gene RORa and the schizophrenia candidate MIR137

    Science.gov (United States)

    Devanna, Paolo; Vernes, Sonja C.

    2014-02-01

    Retinoic acid-related orphan receptor alpha gene (RORa) and the microRNA MIR137 have both recently been identified as novel candidate genes for neuropsychiatric disorders. RORa encodes a ligand-dependent orphan nuclear receptor that acts as a transcriptional regulator and miR-137 is a brain enriched small non-coding RNA that interacts with gene transcripts to control protein levels. Given the mounting evidence for RORa in autism spectrum disorders (ASD) and MIR137 in schizophrenia and ASD, we investigated if there was a functional biological relationship between these two genes. Herein, we demonstrate that miR-137 targets the 3'UTR of RORa in a site specific manner. We also provide further support for MIR137 as an autism candidate by showing that a large number of previously implicated autism genes are also putatively targeted by miR-137. This work supports the role of MIR137 as an ASD candidate and demonstrates a direct biological link between these previously unrelated autism candidate genes.

  17. Occupational doses in pediatric barium meal procedures

    International Nuclear Information System (INIS)

    Ionizing radiation has become an indispensable tool when it comes to diagnosis and therapy. However, its use should happen in a rational manner, taking into account the risks to which the staff is being exposed. Barium meal (BM), or upper gastrointestinal (GI) studies, using fluoroscopy, are widely used for gastroesophageal reflux disease diagnostic in children and professionals are required to stay inside the examination room to position and immobilize pediatric patients during the procedure. Therefore, it is very important that proffessionals strictly follow the technical standards of radiation protection. According to the ICRP and the NCRP recommendations, the annual limit equivalent doses for eyes, thyroid and hands are, espectively, 20 mSv, 150 mSv and 500 mSv. Based on those data, the aim of the current study is to estimate the annual equivalent dose for eyes, thyroid and hands of professionals who perform BM procedures in children. This was done using properly package LiF:Mg,Cu,P thermoluminescent dosimeters in 37 procedures; 2 pairs were positioned near each staff´s eye, 2 pairs on each professional´s neck (on and under the lead protector) and 2 pairs on both staff´s hands. The range of the estimative annual equivalent doses, for eyes, thyroid and hands, are, respectively: 14 – 36 mSv, 7 – 22 mSv and 14 – 58 mSv. Only the closest staff to the patient exceeded the annual equivalent doses in the eyes (around 80% higher than the limit set by ICRP). However, the results from this study, for hands and thyroid, compared to similar studies, show higher values. Therefore, the optimization implementation is necessary, so that the radiation levels can be reduced. (authors)

  18. Sputtered Modified Barium Titanate for Thin-Film Capacitor Applications

    Directory of Open Access Journals (Sweden)

    Robert Mamazza

    2012-04-01

    Full Text Available New apparatus and a new process for the sputter deposition of modified barium titanate thin-films were developed. Films were deposited at temperatures up to 900 °C from a Ba0.96Ca0.04Ti0.82Zr0.18O3 (BCZTO target directly onto Si, Ni and Pt surfaces and characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM and X-ray photoelectron spectroscopy (XPS. Film texture and crystallinity were found to depend on both deposition temperature and substrate: above 600 °C, the as-deposited films consisted of well-facetted crystallites with the cubic perovskite structure. A strongly textured Pt (111 underlayer enhanced the (001 orientation of BCZTO films deposited at 900 °C, 10 mtorr pressure and 10% oxygen in argon. Similar films deposited onto a Pt (111 textured film at 700 °C and directly onto (100 Si wafers showed relatively larger (011 and diminished intensity (00ℓ diffraction peaks. Sputter ambients containing oxygen caused the Ni underlayers to oxidize even at 700 °C: Raising the process temperature produced more diffraction peaks of NiO with increased intensities. Thin-film capacitors were fabricated using ~500 nm thick BCZTO dielectrics and both Pt and Ni top and bottom electrodes. Small signal capacitance measurements were carried out to determine capacitance and parallel resistance at low frequencies and from these data, the relative permittivity (er and resistivity (r of the dielectric films were calculated; values ranged from ~50 to >2,000, and from ~104 to ~1010 Ω∙cm, respectively.

  19. Barium titanate thick films prepared by screen printing technique

    Directory of Open Access Journals (Sweden)

    Mirjana M. Vijatović

    2010-06-01

    Full Text Available The barium titanate (BaTiO3 thick films were prepared by screen printing technique using powders obtained by soft chemical route, modified Pechini process. Three different barium titanate powders were prepared: i pure, ii doped with lanthanum and iii doped with antimony. Pastes for screen printing were prepared using previously obtained powders. The thick films were deposited onto Al2O3 substrates and fired at 850°C together with electrode material (silver/palladium in the moving belt furnace in the air atmosphere. Measurements of thickness and roughness of barium titanate thick films were performed. The electrical properties of thick films such as dielectric constant, dielectric losses, Curie temperature, hysteresis loop were reported. The influence of different factors on electrical properties values was analyzed.

  20. Deoxidation Behavior of Alloys Bearing Barium in Molten Steel

    Institute of Scientific and Technical Information of China (English)

    LI Yang; JIANG Zhou-hua; JIANG Mao-fa; WANG Jun-wen; GU Wen-bing

    2003-01-01

    The deoxidation behaviors of alloys bearing barium in pipe steel were researched with MgO crucible under argon atmosphere in MoSi2 furnace at 1 873 K. The total oxygen contents of molten steel, the distribution, size and morphology of deoxidation products in the steel were surveyed. The metamorphic mechanism for deoxidation products of alloy bearing barium was also discussed. The results show that applying alloy bearing barium to the pipe steel, very low total oxygen contents can be obtained, and deoxidation products, which easily float up from molten steel, can be changed into globular shape and uniformly distributed in steel. The equilibrium time of total oxygen is about 25 min, and the terminal total oxygen contents range from 0.002 0 % to 0.002 2 % after treating with SiCa wire. The best deoxidizers are SiAlBaCa and SiAlBaCaSr.

  1. Economically dissolving barium sulfate scale with a chelating agent

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, E.A.; Scheuerman, R.E.

    1977-06-21

    A composition is described for dissolving a barium sulfate scale from a subterranean or other relatively remote location into which fluid can be flowed. Fluid is flow-flowed into the remote location so that a stream of fluid contacts and flows along the surface of the scale. The composition and flow rate of the fluid are adjusted so that (1) the scale is contacted by a stream of aqueous solution in which each portion contains enough dissolved aminopolyacetic acid salt chelating agent to dissolve barium sulfate, and (2) substantially all upstream portions of the scale are contacted by a succession of portions of the aqueous liquid which are substantially unsaturated with respect to dissolved barium-chelant complex. (5 claims)

  2. Radiation dose in mass screening for gastric cancer with high-concentration barium sulphate compared with moderate-concentration barium sulphate

    International Nuclear Information System (INIS)

    Full text: Recently, high-concentration barium sulfate has been developed and is used in many medical facilities. This study compared radiation dose using high-concentration and moderate-concentration barium sulfate. The dose was evaluated with an experimental method using a gastric phantom and with a clinical examination. In the former, the dose and X-ray tube load were measured on the phantom with two concentrations of barium sulfate. In the latter, the fluoroscopic dose-area product (DAP), the radiographic DAP and their sum, the total DAP, were investigated in 150 subjects (112 males, 38 females) treated with both concentrations of barium sulfate. The effective dose was calculated by the software of PCXMC in every case. The results of the experimental evaluation indicated that the effective dose and X-ray tube load were greater with high-concentration barium sulfate than with moderate-concentration barium sulfate (p < 0.05). The results of the clinical evaluation indicated that the fluoroscopic DAP was greater with moderate-concentration barium sulfate than with high-concentration barium sulfate (p < 0.05), but the radiographic DAP was quite the reverse, so the total DAP and effective dose were almost same with both concentrations of barium sulfate. We conclude that high-concentration barium sulfate does not increase radiation dose in mass screening for gastric cancer.

  3. Compact pulse forming line using barium titanate ceramic material.

    Science.gov (United States)

    Kumar Sharma, Surender; Deb, P; Shukla, R; Prabaharan, T; Shyam, A

    2011-11-01

    Ceramic material has very high relative permittivity, so compact pulse forming line can be made using these materials. Barium titanate (BaTiO(3)) has a relative permittivity of 1200 so it is used for making compact pulse forming line (PFL). Barium titanate also has piezoelectric effects so it cracks during high voltages discharges due to stresses developed in it. Barium titanate is mixed with rubber which absorbs the piezoelectric stresses when the PFL is charged and regain its original shape after the discharge. A composite mixture of barium titanate with the neoprene rubber is prepared. The relative permittivity of the composite mixture is measured to be 85. A coaxial pulse forming line of inner diameter 120 mm, outer diameter 240 mm, and length 350 mm is made and the composite mixture of barium titanate and neoprene rubber is filled between the inner and outer cylinders. The PFL is charged up to 120 kV and discharged into 5 Ω load. The voltage pulse of 70 kV, 21 ns is measured across the load. The conventional PFL is made up of oil or plastics dielectrics with the relative permittivity of 2-10 [D. R. Linde, CRC Handbook of Chemistry and Physics, 90th ed. (CRC, 2009); Xia et al., Rev. Sci. Instrum. 79, 086113 (2008); Yang et al., Rev. Sci. Instrum. 81, 43303 (2010)], which increases the length of PFL. We have reported the compactness in length achieved due to increase in relative permittivity of composite mixture by adding barium titanate in neoprene rubber. PMID:22129008

  4. Dicty_cDB: CHS137 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CH (Link to library) CHS137 (Link to dictyBase) - - - Contig-U16475-1 - (Link to Original site) - - CHS13...7Z 598 - - - - Show CHS137 Library CH (Link to library) Clone ID CHS137 (Link to dicty...iol.tsukuba.ac.jp/CSM/CH/CHS1-B/CHS137Q.Seq.d/ Representative seq. ID - (Link to ...Original site) Representative DNA sequence >CHS137 (CHS137Q) /CSM/CH/CHS1-B/CHS137Q.Seq.d/ XXXXXXXXXXATGTGTA... wall 4.0 %: cytoskeletal 4.0 %: plasma membrane >> prediction for CHS137 is cyt

  5. 75 FR 36629 - Barium Chloride From the People's Republic of China: Continuation of Antidumping Duty Order

    Science.gov (United States)

    2010-06-28

    ... International Trade Administration Barium Chloride From the People's Republic of China: Continuation of... China: Final Results of Expedited Third Sunset Review of Antidumping Duty Order, 74 FR 55814 (October 29... Barium Chloride From China, 75 FR 33824 (June 15, 2010), and Barium Chloride from China (Inv. No....

  6. The adhesiometer: a simple device to measure adherence of barium sulfate to intestinal mucosa.

    Science.gov (United States)

    Salomonowitz, E; Frick, M P; Cragg, A H; Lund, G

    1984-04-01

    A simple, inexpensive device assessing barium sulfate adherence to alimentary tract mucosa was tested in an animal study using pigs and dogs. Interaction of gastric, intestinal, and colonic mucosal lining with three different barium preparations was studied. In both pigs and dogs, barium adherence to gastric mucosa was significantly stronger when compared with colonic mucosa. PMID:6608230

  7. 21 CFR 137.165 - Enriched flour.

    Science.gov (United States)

    2010-04-01

    ... riboflavin, 24 milligrams of niacin, 0.7 milligrams of folic acid, and 20 milligrams of iron. (b) It may... calcium or wheat germ is excluded in calculating ash content. (f) All ingredients from which the food is... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Enriched flour. 137.165 Section 137.165 Food...

  8. Photoionization and Photoelectric Loading of Barium Ion Traps

    OpenAIRE

    Steele, A. V.; Churchill, L. R.; Griffin, P. F.; Chapman, M. S.

    2007-01-01

    Simple and effective techniques for loading barium ions into linear Paul traps are demonstrated. Two-step photoionization of neutral barium is achieved using a weak intercombination line (6s2 1S0 6s6p 3P1, 791 nm) followed by excitation above the ionization threshold using a nitrogen gas laser (337 nm). Isotopic selectivity is achieved by using a near Doppler-free geometry for excitation of the triplet 6s6p 3P1 state. Additionally, we report a particularly simple and efficient trap loading t...

  9. Equations of state for barium in high-pressure phases

    International Nuclear Information System (INIS)

    The universal equation of state with an arbitrary reference point presented by the author (Fang Zheng-Hua 1998 Phys. Rev. B 50 16 238) is applied successfully to the analysis of the experimental compression data of barium in different structural phases (I, II, and V). The comparison given in this paper shows that this equation suits for the isothermal compression behaviour of barium in the high-pressure phases (II and V) better than the Birch-Murnaghan equation. The applicability of equations of state for solids in high-pressure phases is also discussed. (author)

  10. Kinetics of thermal decomposition of barium zirconyl oxalate

    International Nuclear Information System (INIS)

    Kinetics of the thermal decomposition of anhydrous barium zirconyl oxalate and a carbonate intermediate have been studied. Decomposition of the anhydrous oxalate, though it could be explained based on a contracting-cube model, is quite complex. Kinetics of decomposition of the intermediate carbonate Ba2Zr2O5CO3 is greatly influenced by thermal effects during its formation. (α-t) curves are sigmoidal and obey a power law equation followed by first order decay. Presence of carbon in the vacuum-prepared carbonate has a strong deactivating effect. Decomposition of the carbonate is accompanied by growth in particle size of the product barium zirconate. (Author)

  11. Photoionization and Photoelectric Loading of Barium Ion Traps

    CERN Document Server

    Steele, A V; Churchill, L R; Griffin, P F

    2007-01-01

    Simple and effective techniques for loading barium ions into linear Paul traps are demonstrated. Two-step photoionization of neutral barium is achieved using a weak intercombination line (6s2 1S0 6s6p 3P1, 791 nm) followed by excitation above the ionization threshold using a nitrogen gas laser (337 nm). Isotopic selectivity is achieved by using a near Doppler-free geometry for excitation of the triplet 6s6p 3P1 state. Additionally, we report a particularly simple and efficient trap loading technique that employs an in-expensive UV epoxy curing lamp to generate photoelectrons.

  12. Esophageal intramural pseudodiverticulosis characterized by barium esophagography: a case report

    LENUS (Irish Health Repository)

    O'Connor, Owen J

    2010-05-21

    Abstract Introduction Esophageal intramural pseudodiverticulosis is a rare condition characterized by the dilatation of the submucosal glands. Case presentation We present a case of esophageal intramural pseudodiverticulosis in a 72-year-old Caucasian man who presented with dysphagia and with a background history of alcohol abuse. An upper gastrointestinal endoscopy of our patient showed an esophageal stricture with abnormal mucosal appearances, but no malignant cells were seen at biopsy. Appearances on a barium esophagram were pathognomonic for esophageal intramural pseudodiverticulosis. Conclusion We demonstrate the enduring usefulness of barium esophagography in the characterization of abnormal mucosal appearances at endoscopy.

  13. Desorption of 137Cs+ from mosses

    Directory of Open Access Journals (Sweden)

    OLGICA NEDIC

    2002-09-01

    Full Text Available Mosses are biomonitors that accumulate large amounts of various pollutants, including radionuclides. In this work we investigated the possibility of 137Cs extraction from mosses, as well as the significance of species specificity on the efficiency of 137Cs desorption. Salt and acid solutions were used as extraction media. It was shown that a 5 % solution of both ammonium oxalate and phosphoric acid was able to desorb 81.8 % of 137Cs+ from Homalothecium sericeum, which was 39.9 % more than desorption from water. At the same time, most of the desorbed 137Cs+ was incorporated in crystals that precipitated from the solution. An interspecies difference in respect to 137Cs+ desorption was noticed.

  14. Chemical abundance analysis of 19 barium stars

    Science.gov (United States)

    Yang, Guo-Chao; Liang, Yan-Chun; Spite, Monique; Chen, Yu-Qin; Zhao, Gang; Zhang, Bo; Liu, Guo-Qing; Liu, Yu-Juan; Liu, Nian; Deng, Li-Cai; Spite, Francois; Hill, Vanessa; Zhang, Cai-Xia

    2016-01-01

    We aim at deriving accurate atmospheric parameters and chemical abundances of 19 barium (Ba) stars, including both strong and mild Ba stars, based on the high signal-to-noise ratio and high resolution Echelle spectra obtained from the 2.16 m telescope at Xinglong station of National Astronomical Observatories, Chinese Academy of Sciences. The chemical abundances of the sample stars were obtained from an LTE, plane-parallel and line-blanketed atmospheric model by inputting the atmospheric parameters (effective temperatures Teff, surface gravities log g, metallicity [Fe/H] and microturbulence velocity ξt) and equivalent widths of stellar absorption lines. These samples of Ba stars are giants as indicated by atmospheric parameters, metallicities and kinematic analysis about UVW velocity. Chemical abundances of 17 elements were obtained for these Ba stars. Their Na, Al, α- and iron-peak elements (O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Ni) are similar to the solar abundances. Our samples of Ba stars show obvious overabundances of neutron-capture (n-capture) process elements relative to the Sun. Their median abundances of [Ba/Fe], [La/Fe] and [Eu/Fe] are 0.54, 0.65 and 0.40, respectively. The Y I and Zr I abundances are lower than Ba, La and Eu, but higher than the α- and iron-peak elements for the strong Ba stars and similar to the iron-peak elements for the mild stars. There exists a positive correlation between Ba intensity and [Ba/Fe]. For the n-capture elements (Y, Zr, Ba, La), there is an anti-correlation between their [X/Fe] and [Fe/H]. We identify nine of our sample stars as strong Ba stars with [Ba/Fe] >0.6 where seven of them have Ba intensity Ba=2-5, one has Ba=1.5 and another one has Ba=1.0. The remaining ten stars are classified as mild Ba stars with 0.17<[Ba/Fe] <0.54.

  15. Potential value of Cs-137 capsules

    Energy Technology Data Exchange (ETDEWEB)

    Bloomster, C.H.; Brown, D.R.; Bruno, G.A.; Hazelton, R.F.; Hendrickson, P.L.; Lezberg, A.J.; Tingey, G.L.; Wilfert, G.L.

    1985-04-01

    We determined the value of Cs-137 compared to Co-60 as a source for the irradiation of fruit (apples and cherries), pork and medical supplies. Cs-137, in the WESF capsule form, had a value of approximately $0.40/Ci as a substitute for Co-60 priced at approximately $1.00/Ci. The comparison was based on the available curies emitted from the surface of each capsule. We developed preliminary designs for fourteen irradiation facilities; seven were based on Co-60 and seven were based on Cs-137. These designs provided the basis for estimating capital and operating costs which, in turn, provided the basis for determining the value of Cs-137 relative to Co-60 in these applications. We evaluated the effect of the size of the irradiation facility on the value of Cs-137. The cost of irradiation is low compared to the value of the product. Irradiation of apples for disinfestation costs $.01 to .02 per pound. Irradiation for trichina-safe pork costs $.02 per pound. Irradiation of medical supplies for sterilization costs $.07 to .12 per pound. The cost of the irradiation source, either Co-60 or Cs-137, contributed only a minor amount to the total cost of irradiation, about 5% for the fruit and hog cases and about 20% for the medical supply cases. We analyzed the sensitivity of the irradiation costs and Cs-137 value to several key assumptions.

  16. Synthesis of Nanocrystalline Barium Ferrite in Ethanol/Water Media

    Institute of Scientific and Technical Information of China (English)

    M.Montazeri-Pour; A.Ataie

    2009-01-01

    Nanocrystalline particles of barium ferrite magnetic material have been prepared by co-precipitation route using aqueous and non-aqueous solutions of iron and barium chlorides with a Fe/Ba molar ratio of 11 and subsequent drying-annealing treatment. Water and ethanol/water mixture with volume ratio of 3:1 were used as solvents in the process. Coprecipitated powders were annealed at various temperatures for 1 h. FTIR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction), DTA/TGA (differential thermal analy-sis/thermogravimetric analysis) and SEM (scanning electron microscopy) techniques were used to evaluate powder particle characteristics. DTA/TGA results confirmed by those obtained from XRD indicated that the formation of barium ferrite occurs in sample synthesized in ethanol/water solution at a relatively low temperature of 631℃. Nano-size particles of barium ferrite with mean particle size of almost 75 and 100 nm were observed in the SEM micrographs of the samples synthesized in ethanol/water solution after annealing at 700 and 800℃ for 1 h, respectively.

  17. CNO and F abundances in the barium star HD 123396

    CERN Document Server

    Alves-Brito, Alan; Yong, David; Meléndez, Jorge; Vásquez, Sergio

    2011-01-01

    [Abridged] Barium stars are moderately rare chemically peculiar objects which are believed to be the result of the pollution of an otherwise normal star by material from an evolved companion on the asymptotic giant branch (AGB). We aim to derive carbon, nitrogen, oxygen, and fluorine abundances for the first time from infrared spectra of the barium red giant star HD 123396 to quantitatively test AGB nucleosynthesis models for producing barium stars via mass accretion. High-resolution and high S/N infrared spectra were obtained using the Phoenix spectrograph mounted at the Gemini South telescope. The abundances were obtained through spectrum synthesis of individual atomic and molecular lines, using the MOOG stellar line analysis program together with Kurucz's stellar atmosphere models. The analysis was classical, using 1D stellar models and spectral synthesis under the assumption of local thermodynamic equilibrium. We confirm that HD 123396 is a metal-deficient barium star ([Fe/H] = -1.05), with A(C) = 7.88, A...

  18. Removal of barium and radium from groundwater. Environmental research brief

    International Nuclear Information System (INIS)

    A research project was undertaken to investigate processes for removing barium and radium from drinking water. Special emphasis was placed on ion exchange processes that can be used without adding large concentrations of sodium to the water. The wastes from radium and barium removal processes were also characterized, and processes suitable for treatment of ion-exchange brines were evaluated. The report discusses two ion-exchange processes that can be used for barium and radium removal accompanied by either partial or no hardness removal. The calcium-form, strong-acid ion-exchange resin can be used for barium and radium removal without significant change in hardness or the concentration of other salts. This resin can be regenerated with CaC12 brine. The radium-selective complexer (RSC) will remove radium without altering hardness or other salt concentration. The capacity of this resin for waters with low total dissolved solids (TDS) (<1000 to 2000 mg/L TDS) is in excess of 30,000 pCi/dry g; however, if the TDS is increased to about 40,000 mg/L, the capacity drops to 200 to 300 pCi/dry g. Thus using this resin to remove radium from spent brine does not appear feasible

  19. Transfer of 137Cs into mother's milk

    International Nuclear Information System (INIS)

    The concern of nursing mothers about the contamination of foodstuffs after Chernobyl prompted this investigation of radiocaesium transfer to mother's milk. Between May 1987 and December 1988, duplicates of daily food intakes, as well as the corresponding mothers' milk samples, were collected from 12 nursing mothers for two to four weeks in order to measure the 137Cs activity. Once during the collection period, the total-body activity of each of the mothers involved was measured. Based on our results, 137Cs is transferred into mother's milk not only directly from food intake but also from the accumulated body burden. Approximately 19% of the 137Cs activity from the daily food intake and about 13% of the specific 137Cs body activity of the mother are transferred into 1 litre of mother's milk. (author)

  20. Standardization of 137mCs+137mBa by Liquid Scintillation; Calibracion de 137Cs+137mBa por Centelleo Liquido

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, L.; Los Arcos, J.M.; Grau, A.

    1995-07-01

    A procedure for the preparation of a stable, homogeneous solution of 137Cs+''137mBa, for use in liquid scintillation measurements, is described. Its count rate stability and spectral time evolution has been followed for several weeks. The solution has been standardised by the CIEMAT/NIST method in both Ultima-Gold and Insta-Gel, to a combined uncertainty lower than 0,51 % (k=l). (Author) 5 refs.

  1. 21 CFR 137.205 - Bromated whole wheat flour.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Bromated whole wheat flour. 137.205 Section 137... Cereal Flours and Related Products § 137.205 Bromated whole wheat flour. Bromated whole wheat flour... of ingredients, prescribed for whole wheat flour by § 137.200, except that potassium bromate is...

  2. 21 CFR 137.275 - Yellow corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Yellow corn meal. 137.275 Section 137.275 Food and... Related Products § 137.275 Yellow corn meal. Yellow corn meal conforms to the definition and standard of identity prescribed by § 137.250 for white corn meal except that cleaned yellow corn is used instead...

  3. 21 CFR 137.280 - Bolted yellow corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Bolted yellow corn meal. 137.280 Section 137.280... Flours and Related Products § 137.280 Bolted yellow corn meal. Bolted yellow corn meal conforms to the definition and standard of identity prescribed by § 137.255 for bolted white corn meal except that...

  4. 21 CFR 137.285 - Degerminated yellow corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Degerminated yellow corn meal. 137.285 Section 137... Cereal Flours and Related Products § 137.285 Degerminated yellow corn meal. Degerminated yellow corn meal, degermed yellow corn meal, conforms to the definition and standard of identity prescribed by § 137.265...

  5. Design, testing, fabrication and launch support of a liquid chemical barium release payload (utilizing the liquid fluorine-barium salt/hydrazine system)

    Science.gov (United States)

    Stokes, C. S.; Smith, E. W.; Murphy, W. J.

    1972-01-01

    A payload was designed which included a cryogenic oxidizer tank, a fuel tank, and burner section. Release of 30 lb of chemicals was planned to occur in 2 seconds at the optimum oxidizer to fuel ratio. The chemicals consisted of 17 lb of liquid fluorine oxidizer and 13 lb of hydrazine-barium salt fuel mixture. The fuel mixture was 17% barium chloride, 16% barium nitrate, and 67% hydrazine, and contained 2.6 lb of available barium. Two significant problem areas were resolved during the program: explosive valve development and burner operation. The release payload was flight tested, from Wallops Island, Virginia. The release took place at an altitude of approximately 260 km. The release produced a luminous cloud which expanded very rapidly, disappearing to the human eye in about 20 seconds. Barium ion concentration slowly increased over a wide area of sky until measurements were discontinued at sunrise (about 30 minutes).

  6. Functional expression of CD137 (4-1BB) on T helper follicular cells

    Science.gov (United States)

    Alfaro, Carlos; Echeveste, Jose I; Rodriguez-Ruiz, Maria E; Solorzano, Jose L; Perez-Gracia, Jose L; Idoate, Miguel A; Lopez-Picazo, Jose M; Sanchez-Paulete, Alfonso R; Labiano, Sara; Rouzaut, Ana; Oñate, Carmen; Aznar, Angela; Lozano, Maria D; Melero, Ignacio

    2015-01-01

    CD137 (4-1BB) is a surface protein initially discovered to mark activated T lymphocytes. However, its broader expression pattern also encompasses activated NK cells, B cells and myeloid cells, including mature dendritic cells. In this study, we have immunostained for CD137 on paraffin-embedded lymphoid tissues including tonsils, lymph nodes, ectopic tertiary lymphoid tissue in Hashimoto thyroiditis and cancer. Surprisingly, immunostaining mainly decorated intrafollicular lymphocytes in the tissues analyzed, with only scattered staining in interfollicular areas. Moreover, pathologic lymphoid follicles in follicular lymphoma and tertiary lymphoid tissue associated with non-small cell lung cancer showed a similar pattern of immunostaining. Multispectral fluorescence cytometry demonstrated that CD137 expression was restricted to CD4+ CXCR5+ follicular T helper lymphocytes (TFH cells) in tonsils and lymph nodes. Short-term culture of lymph node cell suspensions in the presence of either an agonistic anti-CD137 monoclonal antibody (mAb) or CD137-ligand stimulated the functional upregulation of TFH cells in 3 out of 6 cases, as indicated by CD40L surface expression and cytokine production. As a consequence, immunostimulatory monoclonal antibodies targeting CD137 (such as urelumab and PF-05082566) should be expected to primarily act on this lymphocyte subset, thus modifying ongoing humoral immune responses in patients with autoimmune disease and cancer. PMID:26587331

  7. Experimental Parametric Study of Large-Scale Co60, Na24, and Cs137 Slab Irradiators

    International Nuclear Information System (INIS)

    There are several important parameters in the design of slab irradiators. Target parameters include capacity (energy input per unit mass per unit time), residence time, minimum dose required, maximum dose variation permitted, target dimensions, and target density and composition. Source parameters include source composition (photon energy, source density, and atomic number), total activity (curies), average specific activity, activity distribution, source dimensions, and source-to-target geometry. Large-scale slab sources of low activity level of Co60, Na24, and Cs137 were assembled. The Co60 was in the form of cobalt metal, sg 8.9, the Na24 was in the form of a dilute aqueous solution of Na2C03, sg 1 and the Cs137 was in the form of a compressed solid composed of a homogenous mixture of Cs137 CI and BaS04, sg 2.7. Several static finite slab targets of paraffin wax were used in all experiments. Measurements were made with calibrated instruments of the exposure dose at many points in the target delivered over known periods of time. The specific activity and total activity of the source materials were determined by radiochemical analysis. Source and target parameters, including source dimensions, source activity distribution, and source-to-target geometry, were varied in such a way as to obtain information on specific dose rate and dose distribution in the target. Various absorbers between source and target were also studied. For calculation purposes, the finite source was divided into a number of line elements. Using the uncollided flux equation with the NDA-NBS build-up factor modified for finite media, the contribution of each element to various points in the target was calculated. The conformity of the experimental data to the theoretical is discussed. The data were applied to a set of specifications and for a particular design a comparison is made between available Co60, Na24, and Cs137 sources. (author)

  8. HYBRID AND CHARACTERISTIC OF POLYANILINE- BARIUM TITANATE NANOCOMPOSITE PARTICLES

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Polyaniline-barium titanate (PAn-BaTiO3) ultrafine composite particles were prepared by the oxidative polymerization of aniline with H2O2 while barium titanate nanoparticles were synthesized with a sol-gel method. The infrared spectrogram shows that the polymerization of PAn in the hybrid process of PAn-BaTiO3 is similar with the polymeric process of pure aniline, and there is interaction of PAn and BaTiO3 in the PAn-BaTiO3. SEM and TEM results show that the average diameter of the composite particles is 1.50 μm and the diameters of BaTiO3 nanoparticles are 5-15 nm in the composite particle. The electrical conductivity of the ultrafine composite particles is transformable from 100 to 10-11S/cm by equilibrium doping or dedoping method using various concentration of HCl or NaOH solutions.

  9. The crystal growth of barium flouride in aqueous solution

    Science.gov (United States)

    Barone, J. P.; Svrjcek, D.; Nancollas, G. H.

    1983-06-01

    The kinetics of growth of barium flouride seed crystals were investigated in aqueous solution at 25°C using a constant composition method, in which the supersaturation and ionic strength were maintained constant by the addition of titrants consisting of barium nitrate and potassium flouride solutions. The rates of reaction, studied over a range of supersaturation (σ ≈ 0.4 to 1.0), were interpreted in terms of crystal growth models. A spiral growth mechanism best describes the data, and scanning electron microscopy indicates a three-dimensional growth. In the presence of inorganic additives such as phosphate, however, induction periods precede a morphological two-dimensional crystallization. Coulter Counter results show little crystal agglomeration.

  10. Electromagnetic properties of photodefinable barium ferrite polymer composites

    Directory of Open Access Journals (Sweden)

    Olusegun Sholiyi

    2014-07-01

    Full Text Available This article reports the magnetic and microwave properties of a Barium ferrite powder suspended in a polymer matrix. The sizes for Barium hexaferrite powder are 3–6 μm for coarse and 0.8–1.0 μm for the fine powder. Ratios 1:1 and 3:1 (by mass of ferrite to SU8 samples were characterized and analyzed for predicting the necessary combinations of these powders with SU8 2000 Negative photoresist. The magnetization properties of these materials were equally determined and were analyzed using Vibrating Sample Magnetometer (VSM. The Thru, Reflect, Line (TRL calibration technique was employed in determining complex relative permittivity and permeability of the powders and composites with SU8 between 26.5 and 40 GHz.

  11. Barium titanate nanoparticles: promising multitasking vectors in nanomedicine

    Science.gov (United States)

    Graziana Genchi, Giada; Marino, Attilio; Rocca, Antonella; Mattoli, Virgilio; Ciofani, Gianni

    2016-06-01

    Ceramic materials based on perovskite-like oxides have traditionally been the object of intense interest for their applicability in electrical and electronic devices. Due to its high dielectric constant and piezoelectric features, barium titanate (BaTiO3) is probably one of the most studied compounds of this family. Recently, an increasing number of studies have been focused on the exploitation of barium titanate nanoparticles (BTNPs) in the biomedical field, owing to the high biocompatibility of BTNPs and their peculiar non-linear optical properties that have encouraged their use as nanocarriers for drug delivery and as label-free imaging probes. In this review, we summarize all the recent findings about these ‘smart’ nanoparticles, including the latest, most promising potential as nanotransducers for cell stimulation.

  12. Electromagnetic properties of carbon black and barium titanate composite materials

    Energy Technology Data Exchange (ETDEWEB)

    Wang Guiqin [School of Material Science and Engineering, Dalian University of Technology, Dalian 116023 (China)], E-mail: c2b2chen@163.com; Chen Xiaodong; Duan Yuping; Liu Shunhua [School of Material Science and Engineering, Dalian University of Technology, Dalian 116023 (China)

    2008-04-24

    Nanocrystalline carbon black/barium titanate compound particle (CP) was synthesized by sol-gel method. The phase structure and morphology of compound particle were investigated by X-ray diffraction (XRD), transmission electron microscope (TEM) and Raman spectrum measurements, the electroconductivity was test by trielectrode arrangement and the precursor powder was followed by differential scanning calorimetric measurements (DSC) and thermal gravimetric analysis (TGA). In addition, the complex relative permittivity and permeability of compound particle were investigated by reflection method. The compound particle/epoxide resin composite (CP/EP) with different contents of CP were measured. The results show barium titanate crystal is tetragonal phase and its grain is oval shape with 80-100 nm which was coated by carbon black film. As electromagnetic (EM) complex permittivity, permeability and reflection loss (RL) shown that the compound particle is mainly a kind of electric and dielectric lossy materials and exhibits excellent microwave absorption performance in the X- and Ku-bands.

  13. Thermophysical properties of americium-containing barium plutonate

    International Nuclear Information System (INIS)

    Polycrystalline specimens of americium-containing barium plutonate have been prepared by mixing the appropriate amounts of (Pu0.91Am0.09)O2 and BaCO3 powders followed by reacting and sintering at 1600 K under the flowing gas atmosphere of dry-air. The sintered specimens had a single phase of orthorhombic perovskite structure and were crack-free. Elastic moduli were determined from longitudinal and shear sound velocities. Debye temperature was also determined from sound velocities and lattice parameter measurements. Thermal conductivity was calculated from measured density at room temperature, literature values of heat capacity and thermal diffusivity measured by laser flash method in vacuum. Thermal conductivity of americium-containing barium plutonate was roughly independent of temperature and registered almost the same magnitude as that of BaPuO3 and BaUO3. (author)

  14. Thermoelectric power of barium up to 8 GPa

    Energy Technology Data Exchange (ETDEWEB)

    Ramani, G.; Divakar, C.; Singh, A.K.

    1987-01-15

    The present measurements indicate that the thermoelectric power (TEP) of barium at room temperature and pressure is 15 ..mu..V K/sup -1/, and decreases with increasing pressure, reaching about 4 ..mu..V K/sup -1/ just before the bcc..-->..hcp transition. The TEP shows a discontinuous increase at the bcc..-->..hcp transition beyond which it continues to decrease with increasing pressure.

  15. Acute barium intoxication following ingestion of soap water solution

    Directory of Open Access Journals (Sweden)

    Nandita Joshi

    2012-01-01

    Full Text Available We present a rare case in which a young girl ingested a solution of a hair-removing soap. The ingestion resulted in profound hypokalemia and severe acidosis leading to flaccid paralysis, respiratory arrest and ventricular arrhythmias. Ultimately the patient made complete recovery. The soapwas found to contain barium sulfide. The degree of paralysis and acidosis appeared to be directly related to serum potassium levels.

  16. Barium ferrite powders prepared by milling and annealing

    Directory of Open Access Journals (Sweden)

    R. Nowosielski

    2007-05-01

    Full Text Available Purpose: Microstructure and magnetic properties analysis of barium ferrite powder obtained by milling and heat treatment.Design/methodology/approach: The milling process was carried out in a vibratory mill, which generated vibrations of the balls and milled material inside the container during which their collisions occur. After milling process the powders were annealed in electric chamber furnace. The X-ray diffraction methods were used for qualitative phase analysis of studied powder samples. The distribution of powder particles was determined by a laser particle analyzer. The magnetic hysteresis loops of examined powder material were measured by resonance vibrating sample magnetometer (R-VSM.Findings: The milling process of iron oxide and barium carbonate mixture causes decrease of the crystallite size of involved phases. The X-ray investigations of tested mixture milled for 30 hours and annealed at 950 °C enabled the identification of hard magnetic BaFe12O19 phase and also the presence of Fe2O3 phase in examined material. The Fe2O3 phase is a rest of BaCO3 dissociation in the presence of Fe2O3, which forms a compound of BaFe12O19. The best coercive force (HC for mixture of powders annealed at 950 °C for 10, 20 and 30 hours is 349 kA/m, 366 kA/m and 364 kA/m, respectively. The arithmetic mean of diameter of Fe2O3 and BaCO3 mixture powders after 30 hours of milling is about 6.0 μm.Practical implications: The barium ferrite powder obtained by milling and annealing can be suitable components to produce sintered and elastic magnets with polymer matrix.Originality/value: The results of tested barium ferrite investigations by different methods confirm their utility in the microstructure and magnetic properties analysis of powder materials.

  17. Radiological protection and calibration of an activity meter with cesium and barium sources in a nuclear medicine center; Proteccion radiologica y calibracion de un activimetro con fuentes de cesio y bario en un centro de medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Morales L, M.E. [IPEN INEN Centro de Medicina Nuclear, Av. Aviacion 3799, Lima 34 (Peru)

    2005-07-01

    Presently work is shown the results when gauging a team Deluxe Isotope (Caliper 11) with some sources of Cesium 137 and Barium 133, in a Center of Medicine Nuclear that operates from the anus 1983 in a modern building inside the one Institute of Illnesses Neoplasia (Inn). This Center was equipped initially with teams donated by the International Organism of Atomic Energy (Oa) with those that it develops assistance, educational works and of investigation, giving services to patient of the Inn and other public and private medical centers. (Author)

  18. Role of hexadecapole interaction in proton rich barium isotopes

    International Nuclear Information System (INIS)

    From the systematic analysis of the experimental data on proton rich barium isotopes, it is observed that nuclei in the region z ≥ 50 and N≤82 are the transitional nuclei as they show a shape transition from spherical to deformed shape. An interesting feature of the observed yrast spectra in barium isotopic mass chain is the systematic variation of E2+, E4+ and E6+ excitation energy states from 120Ba to 136Ba. It is observed that these states follow a systematic decreasing trend as move away from 136Ba towards 120Ba. The isotopes 120-128Ba can be taken to be quasi-deformed nuclei having E4+/E2+ ratio larger than 2.7. Based on the systematics of low-lying states and the experimental data of quadrupole moments and B(E2) transition probabilities, the stable barium isotopes range from the approximately spherical 138Ba to l30Ba which is close to the deformed 120-128Ba isotopes. The purpose of the paper is to determine the importance of octupole-octupole and hexadecapole- hexadecapole parts of the two body interaction in reproducing the observed nuclear structure properties of 120-136Ba isotopes

  19. Microwave-hydrothermal synthesis of barium strontium titanate nanoparticles

    International Nuclear Information System (INIS)

    Research highlights: → Barium strontium titanate nanoparticles were obtained by the Hydrothemal microwave technique (HTMW) → This is a genuine technique to obtain nanoparticles at low temperature and short times → Barium strontium titanate free of carbonates with tetragonal structure was grown at 130 oC. - Abstract: Hydrothermal-microwave method (HTMW) was used to synthesize crystalline barium strontium titanate (Ba0.8Sr0.2TiO3) nanoparticles (BST) in the temperature range of 100-130 oC. The crystallization of BST with tetragonal structure was reached at all the synthesis temperatures along with the formation of BaCO3 as a minor impurity at lower syntheses temperatures. Typical FT-IR spectra for tetragonal (BST) nanoparticles presented well defined bands, indicating a substantial short-range order in the system. TG-DTA analyses confirmed the presence of lattice OH- groups, commonly found in materials obtained by HTMW process. FE/SEM revealed that lower syntheses temperatures led to a morphology that consisted of uniform grains while higher syntheses temperature consisted of big grains isolated and embedded in a matrix of small grains. TEM has shown BST nanoparticles with diameters between 40 and 80 nm. These results show that the HTMW synthesis route is rapid, cost effective, and could serve as an alternative to obtain BST nanoparticles.

  20. Preparation of Nanoparticles of Barium Ferrite from Precipitation in Microemulsions

    International Nuclear Information System (INIS)

    Magnetic nanoparticles of barium ferrite (BaFe12O19) have been synthesized using a microemulsion mediated process. The aqueous cores of water-in-oil microemulsions were used as constrained microreactors for the precipitation of precursor carbonate and hydroxide particles. These precursors were then calcined at 925 deg. C for 12 h, during which time they were transformed to the hexagonal ferrite. The pH of reaction was varied between 5 and 12, and it was found that the fraction of non-magnetic hematite (α-Fe2O3) in the particles varied with the pH of reaction, thus affecting the magnetic properties of the particles. The same precursor particles were also prepared by bulk co-precipitation reaction for comparison. It was found that the microemulsion derived nanoparticles of barium ferrite had both higher intrinsic coercivity (Hc) and saturation magnetization (σs) than the particles derived from bulk co-precipitation. Particles were analyzed by electron microscopy, X-ray diffraction, differential thermal analysis (DTA), thermogravimetric analysis (TGA) and vibrating sample magnetometry (VSM). The best barium ferrite particles produced by the microemulsion synthesis method yielded an intrinsic coercivity of 4310 Oe and a saturation magnetization of 60.48 emu/g

  1. Distribution of cesium-137 in reindeer

    Directory of Open Access Journals (Sweden)

    Kristina Rissanen

    1990-08-01

    Full Text Available The influence of the Chernobyl accident in 1986 on the Finnish reindeer herding area was much smaller than the effects of the nuclear bomb tests in the 1960s. Only in one small area somewhat more Cs-137 was deposited than in the rest of the reindeer herding area. From that area 20 reindeer were chosen for investigation of the distribution of Cs-137. All tissues, organs, the skeleton, digestive tract, hide, head and hooves were sampled quantitatively. Three reindeer were pregnant and also the foetuses were studied. The Cs-137 amounts were determined by gammaspectrometric measurements. The results showed that the differences in the Cs-137 concentrations between muscle tissue from different parts of an individual reindeer were not more than 10 percent. Thus it is not essential from which part of the reindeer meat samples for surveillance purposes are taken. The concentration of Cs-137 in edible tissues other than muscle was lower except in the kidneys and scapula cartilage.

  2. Progress on indium and barium single ion optical frequency standards

    CERN Document Server

    Sherman, J A; Metz, S; Nagourney, W; Fortson, N; Sherman, Jeff A.; Trimble, William; Metz, Steven; Nagourney, Warren; Fortson, Norval

    2005-01-01

    We report progress on 115In+ and 137Ba+ single ion optical frequency standards using all solid-state sources. Both are free from quadrupole field shifts and together enable a search for drift in fundamental constants.

  3. Accurate determination of ultra-trace impurities, including europium, in ultra-pure barium carbonate materials through inductively coupled plasma-tandem mass spectrometry

    Science.gov (United States)

    Wu, Shuchao; Zeng, Xiangcheng; Dai, Xuefeng; Hu, Yongping; Li, Gang; Zheng, Cunjiang

    2016-09-01

    Impurities, especially ultra-trace europium (Eu), in ultra-pure barium carbonate materials were accurately determined through inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS). Two reaction modes, namely, mass shift (with O2 as reaction gas) and on-mass modes(with NH3/He and He as reaction gases), were extensively investigated using Eu+ as target analyte. The use of Eu+ → EuO2+, instead of Eu+ → EuO+, as ion pairs in mass shift mode eliminated polyatomic interferences based on Ba matrix ions (135Ba16O2+ on 151Eu16O+ and 137Ba16O2+ on 153Eu16O+). This procedure exhibited enhanced sensitivity and selectivity. When the ICP-MS/MS was operated in NH3 on-mass mode, Eu+ can be determined in its original mass in interference-free conditions because NH3 did not react with Eu+ but with BaO+ to form a neutral product (BaO). The two reaction modes, especially NH3 on mass mode, were validated to be accurate because their resultant isotope ratios of 153Eu/151Eu matched well with that of the natural abundance ratio. The proposed ICP-MS/MS method is a sensitive technique with a limit of detection as low as 2.0 ng L- 1 for 153Eu+. Compared with conventional single-quadrupole (SQ) ICP-MS, both NH3 on-mass mode and O2 mass shift mode in ICP-MS/MS can be used to accurately determine Eu+ in ultra-pure BaCO3 materials. The detected concentration of Eu+ was 4.0 ng L- 1 to 15 ng L- 1, with spiked recoveries ranging from 100%-110%. ICP-MS/MS was also used to eliminate polyatomic interferences, particularly Ba-based interferences, prior to measurement of Gd and Sm. Impurities, including Na, Mg, Al, K, Mn, Fe, Cr, Sr, and Cs, in ultra-pure BaCO3 materials were also determined using ICP-MS/MS in conventional SQ mode.

  4. Simplified assessment of segmental gastrointestinal transit time with orally small amount of barium

    International Nuclear Information System (INIS)

    Objective: To determine the effectiveness and advantage of small amount of barium in the measurement of gastrointestinal transmission function in comparison with radio-opaque pallets. Methods: Protocal 1: 8 healthy volunteers (male 6, female 2) with average age 40 ± 6.1 were subjected to the examination of radio-opaque pellets and small amount of barium with the interval of 1 week. Protocol 2: 30 healthy volunteers in group 1 (male 8, female 22) with average age 42.5 ± 8.1 and 50 patients with chronic functional constipation in group 2 (male 11, female 39) with average age 45.7 ± 7.8 were subjected to the small amount of barium examination. The small amount of barium was made by 30 g barium dissolved in 200 ml breakfast. After taking breakfast which contains barium, objectives were followed with abdominal X-ray at 4, 8, 12, 24, 48, 72, 96 h until the barium was evacuated totally. Results: Small amount of barium presented actual chyme or stool transit. The transit time of radio-opaque pallets through the whole gastrointestinal tract was significantly shorter than that of barium (37 ± 8 h vs. 47 ± 10 h, P < 0.05) in healthy people. The transit times of barium in constipation patients were markedly prolonged in colon (61.1 ± 22 vs. 37.3 ± 11, P < 0.01) and rectum (10.8 ± 3.7 vs. 2.3 ± 0.8 h, P < 0.01) compared with unconstipated volunteers. Transit times in individual gastrointestinal segments were also recorded by using small amount of barium, which allowed identifying the subtypes of constipation. Conclusion: The small amount barium examination is a convenient and low cost method to provide the most useful and reliable information on the transmission function of different gastrointestinal segments and able to classify the subtypes of slow transit constipation

  5. Spatial 137Cs distribution in forest soil

    International Nuclear Information System (INIS)

    This work presents the distribution of radioactive caesium in several types of forest soil originating from the Lesisko reserve (Opole Province, Poland). Vertical distribution of 137Cs isotope was determined in the profiles related to physicochemical properties of different types of soils and their location. Thickness of emerging genetic horizons, structure and morphology of soil profiles were determined. The highest 137Cs activities were found in Of and A horizons. At the same time, there was a sudden drop of 137Cs activity in mineral horizons of soil profiles. By analysis of caesium radioisotope content and its distribution in soil profiles significant correlations were observed between certain physicochemical properties (e.g. pH value, hydrolytic acidity, granulometric composition) of soils in selected forest habitats. (author)

  6. 13.7.Gallbladder and bile duct

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    950323 CT in predicting the efficacy of oralcholelitholysis with bile acids.FU Xianbo (傅贤波),et al.Dept Surg,3rd Teach Hosp,BeijingMed Univ,Beijing,100083.Natl Med J China1993;73(2):81—83.The efficacy of oral cholelitholytic therapywith chenodeoxycholic acid (CDCA) and ur-sodeoxycholic acid (UDCA) in 137 patients withgallstones was compared with their CT pat-terns.The best dissolving results were obtainedfrom patients with the stones in isodense andfaint category (<50Hu) on CT.All the stoneswith high density or heterogeneous calcificationon CT were insoluble.Therefore,they were con-traindicated for oral cholelitholytie therapy.Ac-cording to the abovr,criteria,the rates for disso-lution ranged from 27.7%(38/137).to 66.7%(38/57),and those for complete dissolutionranged from 9.49%(13/137) to 40.7%(11/

  7. Barium and Tc-poor S stars: Binary masqueraders among carbon stars

    OpenAIRE

    Jorissen, A; Van Eck, S.

    1997-01-01

    The current understanding of the origin of barium and S stars is reviewed, based on new orbital elements and binary frequencies. The following questions are addressed: (i) Is binarity a necessary condition to produce a barium star? (ii) What is the mass transfer mode (wind accretion or RLOF?) responsible for their formation? (iii) Do barium stars form as dwarfs or as giants? (iv) Do barium stars evolve into Tc-poor S stars? (v) What is the relative frequency of Tc-rich and Tc-poor S stars?

  8. High Resolution Computed Tomography Appearences of late sequelae of Barium Aspiration in an asymptomatic young child

    International Nuclear Information System (INIS)

    Barium aspiration is a well-known complication of upper gastro-intestinal studies. Consequences of aspiration are generally insignificant and leave no permanent changes in the lung parenchyma. However, large quantities of high density barium, if aspirated, lead to silent interstitial changes and fibrosis. High-resolution computed tomography HRCT appearances of lung changes have been demonstrated in adults; few such reports are available in the pediatric literature. We report a case of a child who aspirated barium 3 months before this presentation. The HRCT appearances of barium aspiration are presented with a review of the literature. (author)

  9. Effects of powdered versus liquid barium on the viscosity of fluids used in modified swallow studies

    Energy Technology Data Exchange (ETDEWEB)

    Baron, J.; Alexander, T. [Univ. of Alberta, Dept. of Radiology, Edmonton, Alberta (Canada)

    2003-06-01

    To determine if the viscosity of thickened juice mixtures used in modified barium swallow studies significantly changes with the addition of powdered barium. We also describe a test formulation created using liquid barium, which has a negligible effect on juice viscosity. The viscosities of water and standardized honey- and nectar-consistency juices mixed with different amounts of powdered barium were measured by timing the laminar flow of a given initial hydrostatic head of fluid under gravity though an orifice of fixed diameter. Standardized juices were then mixed with a liquid formulation of barium and with measured quantities of water to produce viscosities that more closely equated with those of the standardized juices. With the addition of powdered barium, viscosity increased in all fluids, most markedly with the nectar-consistency juice. Liquid barium formulations maintained the viscosities of the original thickened juices. Rendering juices radio-opaque with barium powder results in dramatic increases in the viscosity of the resulting mixture and compromises diagnostic accuracy. Liquid barium preparations have the advantage that they can be rapidly and accurately dispensed by syringe, and their use does not significantly increase the viscosity of the preparation. (author)

  10. BARIUM SULPHATE ABSORPTION AND THE SERUM DIAGNOSIS OF SYPHILIS.

    Science.gov (United States)

    Noguchi, H; Bronfenbrenner, J

    1911-02-01

    The so-called syphilitic antibodies can be removed from a serum by means of absorption with barium sulphate. The removal is due either to an adsorption or a mechanical absorption. The activity of the syphilitic antibodies is thereby unimpaired. The readiness with which the absorption is accomplished with barium sulphate varies considerably with different syphilitic sera. That barium sulphate exerts the same absorbing effect upon non-syphilitic serum components is made evident by the interfering property which the latter manifest in the absorption experiment of the syphilitic antibodies. The selective removal of the serum components, other than the syphilitic antibodies, by means of barium sulphate absorption is, therefore, impossible. On the other hand, a partial removal of these components, with but little removal of the syphilitic antibodies, may be effected when the content of a given serum is poor in syphilitic antibodies and comparatively rich in the indifferent serum components. But this is impossible if the conditions are reversed. The main reasons why some negative syphilitic sera may be so modified by the barium sulphate treatment as to give positive reactions, are explained below, but these apply only to those methods in which inactivated serum is employed. The inactivation reduces the antibody content to about one-fourth to one-fifth of the original. When the serum is very rich in antibodies, this does not affect the result of the fixation test. But when the amount of the antibodies is small, the process of inactivation creates conditions quite unexpected. It may produce such a condition that a given amount of the serum contains, after inactivation, only one or two antibody units, while the other serum components remain undiminished. Here one must not lose sight of the vital fact that these apparently indifferent serum constituents are not at all indifferent in the fixation processes. They may possess affinities which are similar to those of complement

  11. 铝酸钡与氢氧化钡脱硫过程比较%Comparison of Barium Aluminate and Barium Hydroxide Desulfurization Process

    Institute of Scientific and Technical Information of China (English)

    张念炳; 黎志英; 丁彤

    2012-01-01

    The seed precipitation liquor was desulfurized with barium aluminate and barium hydroxide respectively. The desulfurization slag was characterized by XRD analysis, and the desulfurization process was compared. The results show that barium hydroxide exceeds barium aluminate with better desulfurization in terms of effect, speed and duration. In the desulfurization process with barium aluminate, 2BaO · Al2O3 · 5H2O is firstly produced in the reaction of barium aluminate with alkali, and then it reacts with sodium sulfate and sodium carbonate. To compare, Ba(OH)2 · 8H2O directly reacts with sodium sulfate and sodium carbonate in the desulfurization process with barium hydroxide. Both of desulfurization reaction processes can be described with "shrinking core model".%用铝酸钡和氢氧化钡对种分母液进行脱硫试验,对脱硫渣进行XRD分析,并比较脱硫过程.结果表明,氢氧化钡的脱硫效果更好,脱硫完成时间更短,速率更快;铝酸钡先与碱液反应生成2BaO·Al2O3·5H2O,再与硫碱和碳碱反应,而氢氧化钡直接与硫碱和碳碱反应,脱硫过程均可用未反应核模型描述.

  12. The Y137H mutation of VvCYP51 gene confers the reduced sensitivity to tebuconazole in Villosiclava virens

    OpenAIRE

    Fei Wang; Yang Lin; Wei-Xiao Yin; You-Liang Peng; Guido Schnabel; Jun-Bin Huang; Chao-Xi Luo

    2015-01-01

    Management of rice false smut disease caused by Villosiclava virens is dependent on demethylation inhibitor (DMI) fungicides. Investigation of molecular mechanisms of resistance is therefore of upmost importance. In this study the gene encoding the target protein for DMI fungicides (VvCYP51) was cloned and investigated. The VvCYP51 gene in the resistant mutant revealed both a change from tyrosine to histidine at position 137 (Y137H) and elevated gene expression compared to the parental isolat...

  13. Magnetoelectric coupling of multiferroic chromium doped barium titanate thin film probed by magneto-impedance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Jyoti, E-mail: shah.jyoti1@gmail.com; Kotnala, Ravinder K., E-mail: rkkotnala@nplindia.org, E-mail: rkkotnala@gmail.com [Multiferroic and Magnetics Laboratory, CSIR-National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi 110012 (India)

    2014-04-07

    Thin film of BaTiO{sub 3} doped with 0.1 at. % Cr (Cr:BTO) has been prepared by pulsed laser deposition technique. Film was deposited on Pt/SrTiO{sub 3} substrate at 500 °C in 50 mTorr Oxygen gas pressure using KrF (298 nm) laser. Polycrystalline growth of single phase Cr:BTO thin film has been confirmed by grazing angle X-ray diffraction. Cr:BTO film exhibited remnant polarization 6.4 μC/cm{sup 2} and 0.79 MV/cm coercivity. Magnetization measurement of Cr:BTO film showed magnetic moment 12 emu/cc. Formation of weakly magnetic domains has been captured by magnetic force microscopy. Theoretical impedance equation fitted to experimental data in Cole-Cole plot for thin film in presence of transverse magnetic field resolved the increase in grain capacitance from 4.58 × 10{sup −12} to 5.4 × 10{sup −11} F. Film exhibited high value 137 mV/cm-Oe magneto-electric (ME) coupling coefficient at room temperature. The high value of ME coupling obtained can reduce the typical processing steps involved in multilayer deposition to obtain multiferrocity in thin film. Barium titanate being best ferroelectric material has been tailored to be multiferroic by non ferromagnetic element, Cr, doping in thin film form opens an avenue for more stable and reliable spintronic material for low power magnetoelectric random excess memory applications.

  14. Tungsten and barium transport in the internal plasma of hollow cathodes

    Science.gov (United States)

    Polk, James E.; Mikellides, Ioannis G.; Katz, Ira; Capece, Angela M.

    2009-06-01

    The effect of tungsten erosion, transport, and redeposition on the operation of dispenser hollow cathodes was investigated in detailed examinations of the discharge cathode inserts from 8200 h and 30 352 h ion engine wear tests. Erosion and subsequent redeposition of tungsten in the electron emission zone at the downstream end of the insert reduce the porosity of the tungsten matrix, preventing the flow of barium from the interior. This inhibits the interfacial reactions of the barium-calcium-aluminate impregnant with the tungsten in the pores. A numerical model of barium transport in the internal xenon discharge plasma shows that the barium required to reduce the work function in the emission zone can be supplied from upstream through the gas phase. Barium that flows out of the pores of the tungsten insert is rapidly ionized in the xenon discharge and pushed back to the emitter surface by the electric field and drag from the xenon ion flow. This barium ion flux is sufficient to maintain a barium surface coverage at the downstream end greater than 0.6, even if local barium production at that point is inhibited by tungsten deposits. The model also shows that the neutral barium pressure exceeds the equilibrium vapor pressure of the impregnant decomposition reaction over much of the insert length, so the reactions are suppressed. Only a small region upstream of the zone blocked by tungsten deposits is active and supplies the required barium. These results indicate that hollow cathode failure models based on barium depletion rates in vacuum dispenser cathodes are very conservative.

  15. Hypoxia-induced soluble CD137 in malignant cells blocks CD137L-costimulation as an immune escape mechanism

    Science.gov (United States)

    Labiano, Sara; Palazón, Asis; Bolaños, Elixabet; Azpilikueta, Arantza; Sánchez-Paulete, Alfonso R.; Morales-Kastresana, Aizea; Quetglas, Jose I.; Perez-Gracia, José L.; Gúrpide, Alfonso; Rodriguez-Ruiz, Maria; Aznar, M. Angela; Jure-Kunkel, Maria; Berraondo, Pedro; Melero, Ignacio

    2016-01-01

    ABSTRACT Hypoxia is a common feature in solid tumors that has been implicated in immune evasion. Previous studies from our group have shown that hypoxia upregulates the co-stimulatory receptor CD137 on activated T lymphocytes and on vascular endothelial cells. In this study, we show that exposure of mouse and human tumor cell lines to hypoxic conditions (1% O2) promotes CD137 transcription. However, the resulting mRNA is predominantly an alternatively spliced form that encodes for a soluble variant, lacking the transmembrane domain. Accordingly, soluble CD137 (sCD137) is detectable by ELISA in the supernatant of hypoxia-exposed cell lines and in the serum of tumor-bearing mice. sCD137, as secreted by tumor cells, is able to bind to CD137-Ligand (CD137L). Our studies on primed T lymphocytes in co-culture with stable transfectants for CD137L demonstrate that tumor-secreted sCD137 prevents co-stimulation of T lymphocytes. Such an effect results from preventing the interaction of CD137L with the transmembrane forms of CD137 expressed on T lymphocytes undergoing activation. Indeed, silencing CD137 with shRNA renders more immunogenic tumor-cell variants upon inoculation to immunocompetent mice but which readily grafted on immunodeficient or CD8+ T-cell-depleted mice. These mechanisms are interpreted as a molecular strategy deployed by tumors to repress lymphocyte co-stimulation via CD137/CD137L. PMID:26942078

  16. 21 CFR 137.305 - Enriched farina.

    Science.gov (United States)

    2010-04-01

    ... identity prescribed for farina by § 137.300, except that: (1) It contains in each pound not less than 2.0... a part of a trademark or brand, then other written, printed, or graphic matter that is also a part of the trademark or brand may so intervene, if such statement is in such juxtaposition with...

  17. 42 CFR 137.280 - Construction Definitions.

    Science.gov (United States)

    2010-10-01

    ..., DEPARTMENT OF HEALTH AND HUMAN SERVICES TRIBAL SELF-GOVERNANCE Construction Construction Definitions § 137... environmental assessment nor an environmental impact statement is required. Any procedures under this section... environmental effect. CEQ means Council on Environmental Quality in the Office of the President....

  18. 137Cs metabolism in pregnant women

    International Nuclear Information System (INIS)

    Data from two pregnant women contaminated with 137Cs, body burdens of 0.2 and 300 MBq, respectively at the time of the Goiania accident, were compared. The first one, with lower body burden was exposed during the fourth month of pregnancy, while the second became pregnant three years and eight months after 137Cs intake. For the first woman 137Cs concentrations were equal for the mother, infant and placenta, indicating an easy and homogeneous transport of 137Cs from mother to foetus. The whole body monitoring data from the second woman, who became pregnant four years after intake, did not show a reduction in biological half-life during the pregnancy. Cs concentration in the mother was found to be 13 times higher than in the infant. One possible reason for this result is that four years after intake, Cs is supposed to be concentrated mainly in skeletal muscle tissue. During the pregnancy the blood flux becomes higher in most of the organs and tissues except brain, liver and skeletal muscle tissue. (author)

  19. Effects of radionuclides (uranium et cesium 137) on the metabolism of vitamin D in rat

    International Nuclear Information System (INIS)

    Uranium and Cesium 137 (137Cs) are both radionuclides found in the environment as a result of their accidental dispersion and/or natural presence. Consequently, some human populations are exposed to these radioelements mainly through chronic ingestion. Chemical and/or radiological toxicity of uranium and 137Cs has been reported in kidney, liver and brain that play key-roles in vitamin D metabolism. Beside, alterations of both bone and phospho-calcium homeostasis have been reported after an acute or chronic contamination with uranium or 137Cs. However, vitamin D, the major regulator of mineral homeostasis has never been studied up to now. The aim of this work was to investigate in vivo the effects of depleted (DU) or enriched uranium (EU) and of 137Cs on vitamin D3 biosynthetic pathway in liver, kidney and brain. An experimental animal model was used for the first time to demonstrate that chronic exposure with environmental doses of 137Cs and uranium could decrease the vitamin D active form level (1,25(OH)2D3) and lead to molecular modifications of cytochromes P450 (CYPs) enzymes involved in this metabolism and associated nuclear receptors. We demonstrated that both UA and UE contamination affected VDR (vitamin D receptor) and RXRa (retinoid X receptor alpha) expression, and consequently could modulate the expression of vitamin D target genes involved in calcium homeostasis in kidney. These results suggest that these effects could be due to the chemical toxicity of uranium. On the contrary, the main molecular targets of 137Cs are CYPs involved in Vitamin D3 biosynthesis (CYP2R1, CYP27B1) in liver and brain. In this adult rat model such perturbations were not associated with a dys-regulation of mineral homeostasis. Conversely, chronic exposure with 137Cs during postnatal development induce alterations of vitamin D metabolism associated with modifications of bone and phospho-calcium homeostasis, suggesting a greater susceptibility of the growing organism to 137Cs

  20. Chronic contamination with 137Cesium affects Vitamin D3 metabolism in rats

    International Nuclear Information System (INIS)

    Twenty years after Chernobyl disaster, many people are still chronically exposed to low dose of 137Cs, mainly through the food consumption. A large variety of diseases have been described in highly exposed people with 137Cs, which include bone disorders. The aim of this work was to investigate the biological effects of a chronic exposure to 137Cs on Vitamin D3 metabolism, a hormone essential in bone homeostasis. Rats were exposed to 137Cs in their drinking water for 3 months at a dose of 6500 Bq/l (approximately 150 Bq/rat/day), a similar concentration ingested by the population living in contaminated territories in the former USSR countries. Cytochromes P450 enzymes involved in Vitamin D3 metabolism, related nuclear receptors and Vitamin D3 target genes were assessed by real time PCR in liver, kidney and brain. Vitamin D, PTH, calcium and phosphate levels were measured in plasma. An increase in the expression level of cyp2r1 (40%, p 137Cs-exposed rats. However a significant decrease of Vitamin D (1,25(OH)D3) plasma level (53%, p = 0.02) was observed. In brain, cyp2r1 mRNA level was decreased by 20% (p 137Cs contamination. In conclusion, this study showed for the first time that chronic exposure with post-accidental doses of 137Cs affects Vitamin D3 active form level and induces molecular modifications of CYPs enzymes involved its metabolism in liver and brain, without leading to mineral homeostasis disorders

  1. Anion and cation diffusion in barium titanate and strontium titanate

    International Nuclear Information System (INIS)

    Perovskite oxides show various interesting properties providing several technical applications. In many cases the defect chemistry is the key to understand and influence the material's properties. In this work the defect chemistry of barium titanate and strontium titanate is analysed by anion and cation diffusion experiments and subsequent time-of-flight secondary ion mass spectrometry (ToF-SIMS). The reoxidation equation for barium titanate used in multi-layer ceramic capacitors (MLCCs) is found out by a combination of different isotope exchange experiments and the analysis of the resulting tracer diffusion profiles. It is shown that the incorporation of oxygen from water vapour is faster by orders of magnitude than from molecular oxygen. Chemical analysis shows the samples contain various dopants leading to a complex defect chemistry. Dysprosium is the most important dopant, acting partially as a donor and partially as an acceptor in this effectively acceptor-doped material. TEM and EELS analysis show the inhomogeneous distribution of Dy in a core-shell microstructure. The oxygen partial pressure and temperature dependence of the oxygen tracer diffusion coefficients is analysed and explained by the complex defect chemistry of Dy-doped barium titanate. Additional fast diffusion profiles are attributed to fast diffusion along grain boundaries. In addition to the barium titanate ceramics from an important technical application, oxygen diffusion in cubic, nominally undoped BaTiO3 single crystals has been studied by means of 18O2/16O2 isotope exchange annealing and subsequent determination of the isotope profiles in the solid by ToF-SIMS. It is shown that a correct description of the diffusion profiles requires the analysis of the diffusion through the surface space-charge into the material's bulk. Surface exchange coefficients, space-charge potentials and bulk diffusion coefficients are analysed as a function of oxygen partial pressure and temperature. The data

  2. Distribution of Cs-137 in lake sediment

    International Nuclear Information System (INIS)

    This study on Cs-137 from the Chernobyl accident was conducted in Lake Raaksjoen, an oligotrophic, mesohumic lake in central Sweden. The purpose was to determine the areal as well as the vertical distribution of Cs-137 in lake sediment and to see if the results could be explained by parameters such as morphometry of the lake, wind exposure, currents, wave action etc. Sediments cores were taken on 19 sites in March 1992 when the lake still was ice covered and these sampling-sites were spread all over the lake. The sediment cores were taken to the laboratory and sliced into 0.5-1 cm increments down to a sediment depth of 10 cm. The sediment increments were analysed on physical parameters such as density and water content and chemical parameters like C, N, Fe, Mn and Ca together with a measure of Cs-137 concentrations using a sodium iodine detector. The average concentration of cesium-137 in the sediment in Lake Raaksjoen was 30-35 kBq/m2, which coincide with the amount deposited on the lake (30-40 kBq/m2). There was a clear tendency for the concentration to increase with water depth, as a result of sediment focusing. The vertical distribution of Cs-137 was quite uniform for all sampling-sites with a peak about a centimeter down in the sediment and then decreasing concentrations downwards to a negligible value not affected by the Chernobyl accident at a sediment depth of 10 cm. There were no connections found between cesium content and other substances analysed

  3. Reactive barriers for 137Cs retention.

    Science.gov (United States)

    Krumhansl, J L; Brady, P V; Anderson, H L

    2001-02-01

    137Cs was dispersed globally by cold war activities and, more recently, by the Chernobyl accident. Engineered extraction of 137Cs from soils and groundwaters is exceedingly difficult. Because the half-life of 137Cs is only 30.2 years, remediation might be more effective (and less costly) if 137Cs bioavailability could be demonstrably limited for even a few decades by use of a reactive barrier. Essentially permanent isolation must be demonstrated in those few settings where high nuclear level wastes contaminated the environment with 135Cs (half-life 2.3 x 10(6) years) in addition to 137Cs. Clays are potentially a low-cost barrier to Cs movement, though their long-term effectiveness remains untested. To identify optimal clays for Cs retention, Cs desorption was measured for five common clays: Wyoming Montmorillonite (SWy-1), Georgia Kaolinites (KGa-1 and KGa-2), Fithian Illite (F-Ill), and K-Metabentonite (K-Mbt). Exchange sites were pre-saturated with 0.16 M CsCl for 14 days and readily exchangeable Cs was removed by a series of LiNO3 and LiCl washes. Washed clays were then placed into dialysis bags and the Cs release to the deionized water outside the bags measured. Release rates from 75 to 139 days for SWy-1, K-Mbt and F-Ill were similar; 0.017% to 0.021% sorbed Cs released per day. Both kaolinites released Cs more rapidly (0.12% to 0.05% of the sorbed Cs per day). In a second set of experiments, clays were Cs-doped for 110 days and subjected to an extreme and prolonged rinsing process. All the clays exhibited some capacity for irreversible Cs uptake. However, the residual loading was greatest on K-Mbt (approximately 0.33 wt.% Cs). Thus, this clay would be the optimal material for constructing artifical reactive barriers.

  4. Microstructure of polymer composite with barium ferrite powder

    Directory of Open Access Journals (Sweden)

    R. Nowosielski

    2008-12-01

    Full Text Available Purpose: The aim of the paper is the microstructure characterization of commercial BaFe12O19 powder and its composite material in polymer matrix; XRD (X-Ray Diffraction and SEM (Scanning Electron Microscopy methods were applied.Design/methodology/approach: The Rietveld method appeared to be very useful in the verification of the qualitative phase composition and in the determination of phase abundance. Hill and Howard procedure was applied for quantitative phase analysis. The parameters of the individual diffraction line profiles were determined by PRO-FIT Toraya procedure. The morphology of barium ferrite powders and a fracture surface of the examined composite material was analyzed using the scanning electron microscope.Findings: The X-ray diffraction analysis enabled the identification of BaFe12O19 and Fe2O3 phases in examined material. Basing on Rietveld and Toraya methods the determination of lattice parameters, crystallite size and the lattice distortion was performed. Distribution of powders of barium ferrite in polymer matrix is irregular and powder particles are of irregular shapes and different sizes.Research limitations/implications: Maked researches are limited only to characterization the microstructure of commercial material, because obtained results will be helpful to prepare barium ferrite powders by mechanical alloying and subsequent annealing in the future. As prepared BaFe12O19 powders will be used as the starting material for magnets bonded with polymer material.Originality/value: The obtained results of investigations by different methods of structure analysis confirm their useful in the microstructure analysis of powder materials.

  5. Barium Swallow Findings in the Evaluation of Patients with Dysphagia

    Directory of Open Access Journals (Sweden)

    Amirhosein Hashemi Attar

    2011-05-01

    Full Text Available Background/Objective: Dysphagia is a subjective"nsensation of difficulty in swallowing that has a wide"nrange of etiologies from psychosomatic disorders"nto high grade neoplasms. In this study we evaluated"nbarium swallow findings of patients with dysphagia."nPatients and Methods: We evaluated 200 patients"n(117 men, 83 women; mean age, 49.6 years with"ncomplaint of dysphagia. Fluoroscopic barium"nswallow was done for all the patients and they were"nreviewed for primary peristalsis (presence or absence,"nAbstracts"nS62 Iran J Radiol 2011, 8 (Supp.1"nAbstracts"nimpaired lower esophageal sphincter, esophageal dilatation, delayed emptying of barium, nonperistaltic contractions, stricture and filling defects. Clinical and in some cases endoscopic or manometric follow up was done for all patients."nResults: We had 134 (67% normal barium swallow"nexams with uncomplicated clinical courses. Sixty"nsix patients (33% had abnormal imaging findings"nincluding stricture in 24 patients (12%, filling defect"nin 12 patients (6% and mucosal abnormality in 14"n(7% patients (six cases of mucosal irregularity, three"ncases of mucosal ulceration and five cases of mucosal"nherniation, Bird's beak sign in three patients (1.5%,"ntertiary spasm in six patients (3% and hiatal hernia in"nseven patients (3.5%."nConclusion: In the majority of patients with dysphagia,"nbarium swallow is the only paraclinical study needed"nto plan proper treatment. If radiographic findings are"nequivocal, endoscopy or manometry may be required"nfor more certain diagnosis.

  6. Barium strontium titanate powders prepared by spray pyrolysis

    International Nuclear Information System (INIS)

    Ultasonic spray pyrolysis (SP) has been investigated for the production of the barium strontium titanate (BST) powders from the polymeric precursors. The processing parameters, such as flux of aerosol and temperature profile inside the furnace, were optimized to obtain single phase BST. The powders were characterized by the methods of X-ray diffraction analysis, SEM, EDS and TEM. The obtained powders were submicronic, consisting of spherical, polycrystalline particles, with internal nanocrystalline structure. Crystallite size of 10 nm, calculated using Rietveld refinement, is in a good agreement with results of HRTEM

  7. A barium-rich binary central star in Abell 70

    CERN Document Server

    Boffin, Henri M J; Frew, D J; Acker, A; Köppen, J; Moffat, A F J; Parker, Q A

    2011-01-01

    We have found the central star of Abell 70 (PN G038.1-25.4, hereafter A 70) to be a binary consisting of a G8 IV-V secondary and a hot white dwarf. The secondary shows enhanced Ba II and Sr II features, firmly classifying it as a barium star. The nebula is found to have Type-I chemical abundances with helium and nitrogen enrichment, which combined with future abundance studies of the central star, will establish A 70 as a unique laboratory for studying s-process AGB nucleosynthesis.

  8. Strain engineered barium strontium titanate for tunable thin film resonators

    Energy Technology Data Exchange (ETDEWEB)

    Khassaf, H.; Khakpash, N. [Department of Materials Science and Engineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269 (United States); Sun, F. [Department of Physics, University of Connecticut, Storrs, Connecticut 06269 (United States); Sbrockey, N. M.; Tompa, G. S. [Structured Materials Industries, Inc., Piscataway, New Jersey 08854 (United States); Kalkur, T. S. [Department of Electrical and Computer Engineering, University of Colorado at Colorado Springs, Colorado Springs, Colorado 80918 (United States); Alpay, S. P., E-mail: p.alpay@ims.uconn.edu [Department of Materials Science and Engineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269 (United States); Department of Physics, University of Connecticut, Storrs, Connecticut 06269 (United States)

    2014-05-19

    Piezoelectric properties of epitaxial (001) barium strontium titanate (BST) films are computed as functions of composition, misfit strain, and temperature using a non-linear thermodynamic model. Results show that through adjusting in-plane strains, a highly adaptive rhombohedral ferroelectric phase can be stabilized at room temperature with outstanding piezoelectric response exceeding those of lead based piezoceramics. Furthermore, by adjusting the composition and the in-plane misfit, an electrically tunable piezoelectric response can be obtained in the paraelectric state. These findings indicate that strain engineered BST films can be utilized in the development of electrically tunable and switchable surface and bulk acoustic wave resonators.

  9. K-shell fluorescence yields of barium and lanthanum

    International Nuclear Information System (INIS)

    K-shell fluorescence yields for barium and lanthanum have been measured adopting simple 2π geometrical configuration and employing a weak 57Co radioactive source. A scintillation spectrometer with an NaI(Tl) detector of dimensions 44.5 mm diameterx50 mm thickness was employed for the detection and measurement of radiation. The results obtained are in good agreement with the best-fitted values of and also with the other experimental values, indicating that our simple method can be extended to determine fluorescence parameters of high Z materials.

  10. The Kerr nonlinearity of the beta-barium borate crystal

    DEFF Research Database (Denmark)

    Bache, Morten; Guo, Hairun; Zhou, Binbin;

    2013-01-01

    A popular crystal for ultrafast cascading experiments is beta-barium-borate (β-BaB2O4, BBO). It has a decent quadratic nonlinear coefficient, and because the crystal is anisotropie it can be birefringence phase-matched for type I (oo → e) second-harmonic generation (SHG). For femtosecond...... experiments BBO is popular because of low dispersion and a high damage threshold. The main attractive property of ultrafast cascading is that the induced cascading nonlinearity nI 2, casc can be negative, i.e. generate a self-defocusing Kerr-like nonlinearity. However, the material Kerr nonlinearity nI 2...

  11. The Kerr nonlinearity of the beta-barium borate crystal

    OpenAIRE

    Bache, Morten; Guo, Hairun; Zhou, Binbin; Zeng, Xianglong

    2013-01-01

    A popular crystal for ultrafast cascading experiments is beta-barium-borate (β-BaB2O4, BBO). It has a decent quadratic nonlinear coefficient, and because the crystal is anisotropie it can be birefringence phase-matched for type I (oo → e) second-harmonic generation (SHG). For femtosecond experiments BBO is popular because of low dispersion and a high damage threshold. The main attractive property of ultrafast cascading is that the induced cascading nonlinearity nI 2, casc can be negative, i.e...

  12. Control on Crystal Forms of Ultrafine Barium Carbonate Particles and Study on its Mechanism

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Barium carbonate particles were prepared by using homogeneous precipitation method and co-precipitation method respectively. Through adding different crystalline controlling modifiers, Barium carbonate particles in five different shapes including linear, needle-like, pillarlike, sphere-like and dumbbell-like were synthesized. These particles were characterized by SEM and XRD, and their synthetic mechanism was discussed in this paper.

  13. Investigation on the effects of milling atmosphere on synthesis of barium ferrite/magnetite nanocomposite

    NARCIS (Netherlands)

    Molaei, M.J.; Ataie, A.; Raygan, S.; Picken,n S.J.

    2011-01-01

    In this research, barium ferrite /magnetite nanocomposites synthesized via a mechano-chemical route. Graphite was used in order to reduce hematite content of barium ferrite to magnetite to produce a magnetic nanocomposite. The effects of processing conditions on the powder characteristics were inves

  14. Acute respiratory failure caused by aspiration of high density barium: A case report

    International Nuclear Information System (INIS)

    Accidental aspiration of barium contrast medium during the upper gastrointestinal study can occur in patients with swallowing disorder, especially in the elderly patients. We experienced a case of respiratory failure followed by death within a few hours in 85 year-old patient after barium aspiration

  15. New efficient catalyst for ammonia synthesis: barium-promoted cobalt on carbon

    DEFF Research Database (Denmark)

    Hagen, Stefan; Barfod, Rasmus; Fehrmann, Rasmus;

    2002-01-01

    Barium-promoted cobalt catalysts supported on carbon exhibit higher ammonia activities at synthesis temperatures than the commercial, multipromoted iron catalyst and also a lower ammonia......Barium-promoted cobalt catalysts supported on carbon exhibit higher ammonia activities at synthesis temperatures than the commercial, multipromoted iron catalyst and also a lower ammonia...

  16. Standardization of 137mCs+137mBa by Liquid Scintillation

    International Nuclear Information System (INIS)

    A procedure for the preparation of a stable, homogeneous solution of 137Cs+''137mBa, for use in liquid scintillation measurements, is described. Its count rate stability and spectral time evolution has been followed for several weeks. The solution has been standardised by the CIEMAT/NIST method in both Ultima-Gold and Insta-Gel, to a combined uncertainty lower than 0,51 % (k=l). (Author) 5 refs

  17. Anion and cation diffusion in barium titanate and strontium titanate; Anionen- und Kationendiffusion in Barium- und Strontiumtitanat

    Energy Technology Data Exchange (ETDEWEB)

    Kessel, Markus Franz

    2012-12-19

    Perovskite oxides show various interesting properties providing several technical applications. In many cases the defect chemistry is the key to understand and influence the material's properties. In this work the defect chemistry of barium titanate and strontium titanate is analysed by anion and cation diffusion experiments and subsequent time-of-flight secondary ion mass spectrometry (ToF-SIMS). The reoxidation equation for barium titanate used in multi-layer ceramic capacitors (MLCCs) is found out by a combination of different isotope exchange experiments and the analysis of the resulting tracer diffusion profiles. It is shown that the incorporation of oxygen from water vapour is faster by orders of magnitude than from molecular oxygen. Chemical analysis shows the samples contain various dopants leading to a complex defect chemistry. Dysprosium is the most important dopant, acting partially as a donor and partially as an acceptor in this effectively acceptor-doped material. TEM and EELS analysis show the inhomogeneous distribution of Dy in a core-shell microstructure. The oxygen partial pressure and temperature dependence of the oxygen tracer diffusion coefficients is analysed and explained by the complex defect chemistry of Dy-doped barium titanate. Additional fast diffusion profiles are attributed to fast diffusion along grain boundaries. In addition to the barium titanate ceramics from an important technical application, oxygen diffusion in cubic, nominally undoped BaTiO{sub 3} single crystals has been studied by means of {sup 18}O{sub 2}/{sup 16}O{sub 2} isotope exchange annealing and subsequent determination of the isotope profiles in the solid by ToF-SIMS. It is shown that a correct description of the diffusion profiles requires the analysis of the diffusion through the surface space-charge into the material's bulk. Surface exchange coefficients, space-charge potentials and bulk diffusion coefficients are analysed as a function of oxygen partial

  18. Biological effects of 137Cs, incorporated into organism of rats

    International Nuclear Information System (INIS)

    Results of investigating mutagenous and hemotoxic effects of 137Cs on blood lymphocytes of rats are presented. 137Cs was orally administrated into organism of rats as 270 kBq/g chloride solution. 137Cs mutagenous effect was studied on metaphase plates of rat blood lymphocytes in course of rats lifetime experiment. It is stated that 137Cs inducing severe disturbances of genetic material in a great quantity of blood lymphocytes, causes their total killing

  19. 7 CFR 4280.137 - Repurchase from holder.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Repurchase from holder. 4280.137 Section 4280.137... Efficiency Improvements Program Section B. Guaranteed Loans § 4280.137 Repurchase from holder. Any repurchase from a holder must be in accordance with § 4279.78 of this chapter....

  20. 25 CFR 137.2 - Availability of water.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Availability of water. 137.2 Section 137.2 Indians BUREAU... COSTS, SAN CARLOS INDIAN IRRIGATION PROJECT, ARIZONA § 137.2 Availability of water. Pursuant to section... notice to announce when water is actually available for lands in private ownership under the project...

  1. 21 CFR 137.265 - Degerminated white corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Degerminated white corn meal. 137.265 Section 137... Cereal Flours and Related Products § 137.265 Degerminated white corn meal. (a) Degerminated white corn meal, degermed white corn meal, is the food prepared by grinding cleaned white corn and removing...

  2. 47 CFR 87.137 - Types of emission.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Types of emission. 87.137 Section 87.137... Technical Requirements § 87.137 Types of emission. (a) The assignable emissions, corresponding emission designators and authorized bandwidths are as follows: Class of emission Emission designator...

  3. 33 CFR 137.30 - Objectives and performance factors.

    Science.gov (United States)

    2010-07-01

    ... factors. 137.30 Section 137.30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Practices § 137.30 Objectives and performance factors. (a) Objectives. This part is intended to result in... which the facility is located. (b) Performance factors. In order to meet this part and to meet...

  4. Quantitative Model for Estimating Soil Erosion Rates Using 137Cs

    Institute of Scientific and Technical Information of China (English)

    YANGHAO; GHANGQING; 等

    1998-01-01

    A quantitative model was developed to relate the amount of 137Cs loss from the soil profile to the rate of soil erosion,According th mass balance model,the depth distribution pattern of 137Cs in the soil profile ,the radioactive decay of 137Cs,sampling year and the difference of 137Cs fallout amount among years were taken into consideration.By introducing typical depth distribution functions of 137Cs into the model ,detailed equations for the model were got for different soil,The model shows that the rate of soil erosion is mainly controlled by the depth distrbution pattern of 137Cs ,the year of sampling,and the percentage reduction in total 137Cs,The relationship between the rate of soil loss and 137Cs depletion i neither linear nor logarithmic,The depth distribution pattern of 137Cs is a major factor for estimating the rate of soil loss,Soil erosion rate is directly related with the fraction of 137Cs content near the soil surface. The influences of the radioactive decay of 137Cs,sampling year and 137Cs input fraction are not large compared with others.

  5. 29 CFR 102.137 - Public observation of Board meetings.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 2 2010-07-01 2010-07-01 false Public observation of Board meetings. 102.137 Section 102.137 Labor Regulations Relating to Labor NATIONAL LABOR RELATIONS BOARD RULES AND REGULATIONS, SERIES 8 Open Meetings § 102.137 Public observation of Board meetings. Every portion of every meeting of...

  6. Ruthenium and hafnium abundances in giant and dwarf barium stars

    CERN Document Server

    Allen, D M

    2007-01-01

    We present abundances for Ru and Hf, compare them to abundances of other heavy elements, and discuss the problems found in determining Ru and Hf abundances with laboratory gf-values in the spectra of barium stars. We determined Ru and Hf abundances in a sample of giant and dwarf barium stars, by the spectral synthesis of two RuI (4080.574A and 4757.856A) and two HfII (4080.437A and 4093.155A) transitions. The stellar spectra were observed with FEROS/ESO, and the stellar atmospheric parameters lie in the range 4300 < Teff/K < 6500, -1.2 < [Fe/H] <= 0 and 1.4 <= log g < 4.6. The HfII 4080A and the RuI 4758A observed transitions result in a unreasonably high solar abundance, given certain known uncertainties, when fitted with laboratory gf-values. For these two transitions we determined empirical gf-values by fitting the observed line profiles of the spectra of the Sun and Arcturus. For the sample stars, this procedure resulted in a good agreement of Ru and Hf abundances given by the two availa...

  7. Study of barium bismuth titanate prepared by mechanochemical synthesis

    Directory of Open Access Journals (Sweden)

    Lazarević Z.Ž.

    2009-01-01

    Full Text Available Barium-bismuth titanate, BaBi4Ti4O15 (BBT, a member of Aurivillius bismuth-based layer-structure perovskites, was prepared from stoichiometric amounts of barium titanate and bismuth titanate obtained via mechanochemical synthesis. Mechanochemical synthesis was performed in air atmosphere in a planetary ball mill. The reaction mechanism of BaBi4Ti4O15 and the preparation and characteristics of BBT ceramic powders were studied using XRD, Raman spectroscopy, particle analysis and SEM. The Bi-layered perovskite structure of BaBi4Ti4O15 ceramic forms at 1100 °C for 4 h without a pre-calcination step. The microstructure of BaBi4Ti4O15 exhibits plate-like grains typical for the Bi-layered structured material and spherical and polygonal grains. The Ba2+ addition leads to changes in the microstructure development, particularly in the change of the average grain size.

  8. Materials Synthesis Of Barium Hexa ferrite Used Local Natural Resources

    International Nuclear Information System (INIS)

    The magnetic materials of barium hexa ferrites, Ba O.6Fe2O3 successfully synthesized by powder metallurgy method used local natural resources from materials waste of steel fabrication (HSM, CRM), waste of polymer fabrication (LK) as well as iron sands (PBA). These waste as well as iron sands were the main resources of iron oxide, Fe2O3. The barium oxide used in this experiments are from BaCO3 product of Merck, and BaCO4 which is commercially available in the market as barite. Phase identification by x-ray diffraction technique show the synthesized magnetic materials are agreed with the available commercial product, (SUMI). The energy product maximum (BH)max measured by vibrating sample magnetometer (VSM) for the samples used HSM-, CRM- and BaCO3 as basic materials are 1.141 MGOe and 1.136 MGOe while SUMI is 1.142 MGOe. However for the samples made from LK-, PBA- used of BaCO3 or CRM- with barite, the energy product maximum (BH)max are relatively lower than commercial product

  9. Microstructure of composite material with powders of barium ferrite

    Directory of Open Access Journals (Sweden)

    R. Nowosielski

    2006-04-01

    Full Text Available Purpose: The aim of the present work is the microstructure characterization of commercial powder BaFe12O19 (as-prepared and composite material with BaFe12O19 powders and polymer matrix, using XRD (X-Ray Diffraction and SEM (Scanning Electron Microscopy methods.Design/methodology/approach: The morphology of barium ferrite powders and a fracture surface of the examined composite material was realized by using the scanning electron microscope. The methods of X-ray diffraction were used for the qualitative phase analysis. The parameters of diffraction line profiles were determined by PRO-FIT Toraya procedure.Findings: The X-ray diffraction analysis permitted on identification the BaFe12O19 and Fe2O3 phases in an examined material. Basing on Toraya method is determination of: lattice parameters, crystallite size (D and the lattice distortion (. Distribution of powders of barium ferrite in polymer matrix is irregular and powder particles have irregular shapes and dimensions.Research limitations/implications: For future research the X-ray analysis should be performed by the Rietveld method, which allows to characterization the microstructure of tested material and verification of its qualitative phase composition.Originality/value: The applied Toraya method of structure analysis appeared to be very useful in the microstructure analysis.

  10. Redox processes in highly yttrium-doped barium titanate

    International Nuclear Information System (INIS)

    The changes of microstructure occurring during oxidation of the reduced form of yttrium-doped barium titanate (Ba1-xYx?Ti1-x4+Tix3+O3) have been studied. Samples were sintered under reduction conditions at PO2=10-4Pa and oxidized by annealing at high temperatures (1150 and 1350 deg. C) in air. Depending on yttrium concentration, the oxidation of the reduced form of the yttrium-doped BaTiO3 caused precipitation of the phase Ba6Ti17O40 or the phases Ba6Ti17O40 and Y2Ti2O7. The precipitates had well-defined orientational relationships with the perovskite matrix. Oxidation of the reduced form of doped barium titanate results in formation of the phase Ba1-xYx?Ti1-x/44+(VTi-bar )x/4O3 responsible for increase in the resistance of outer grain layers, which lie between grain boundaries and grain

  11. Thermal expansion behaviour of barium and strontium zirconium phosphates

    Indian Academy of Sciences (India)

    P Srikari Tantri; K Geetha; A M Umarji; Sheela K Ramasesha

    2000-12-01

    Ba1.5–SrZr4P5SiO24 compounds with = 0, 0.25, 0.5, 0.75, 1.0, 1.25 and 1.5, belonging to the low thermal expansion NZP family were synthesized by the solid state reaction method. The XRD pattern could be completely indexed with respect to R$\\bar{3}$ space group indicating the ordering of vacancy at the divalent cation octahedral sites. The microstructure and bulk thermal expansion coefficient from room temperature to 800°C of the sintered samples have been studied. All the samples show very low coefficient of thermal expansion (CTE), with = 0 samples showing negative expansion. A small substitution of strontium in the pure barium compound changes the sign of CTE. Similarly, = 1.5 sample (pure strontium) shows a positive CTE and a small substitution of barium changes its sign. = 1.0 and 1.25 samples have almost constant CTE over the entire temperature range. The low thermal expansion of these samples can be attributed to the ordering of the ions in the crystal structure of these materials.

  12. The liquid scintillation counting efficiency for 137mCs+137mBa and ''129 I

    International Nuclear Information System (INIS)

    We compute the liquid scintillation counting efficiency for 137Cs+137mBa and ''129 I taking into account the scintillator chemical composition. We consider the beta transition shape factors for the for bidden beta transitions of these nuclides, and the effects of 137mBa and 129mXe half-lives on the total counting efficiency. (Author) 8 refs

  13. Bio-based barium alginate film: Preparation, flame retardancy and thermal degradation behavior.

    Science.gov (United States)

    Liu, Yun; Zhang, Chuan-Jie; Zhao, Jin-Chao; Guo, Yi; Zhu, Ping; Wang, De-Yi

    2016-03-30

    A bio-based barium alginate film was prepared via a facile ionic exchange and casting approach. Its flammability, thermal degradation and pyrolysis behaviors, thermal degradation mechanism were studied systemically by limiting oxygen index (LOI), vertical burning (UL-94), microscale combustion calorimetry (MCC), thermogravimetric analysis (TGA) coupled with Fourier transform infrared analysis (FTIR) and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). It showed that barium alginate film had much higher LOI value (52.0%) than that of sodium alginate film (24.5%). Moreover, barium alginate film passed the UL-94 V-0 rating, while the sodium alginate film showed no classification. Importantly, peak of heat release rate (PHRR) of barium alginate film in MCC test was much lower than that of sodium alginate film, suggested that introduction of barium ion into alginate film significantly decreased release of combustible gases. TG-FTIR and Py-GC-MS results indicated that barium alginate produced much less flammable products than that of sodium alginate in whole thermal degradation procedure. Finally, a possible degradation mechanism of barium alginate had been proposed. PMID:26794953

  14. Preparation of Barium Titanate Nanopowder through Thermal Decomposition of Peroxide Precursor and Its Formation Mechanism

    Institute of Scientific and Technical Information of China (English)

    PENG, Yangxi; CHEN, Qiyuan; LIU, Shijun

    2009-01-01

    H_2TiO_3 was dissolved in the mixture of hydrogen formed peroxide and ammonia under the pH range of 8-10 with a transparent yellow solution formed. When an equivalent mole of Ba~(2+) solution was added into the yellow solution, the precipitate produced was the peroxide precursor of barium titanate. The cubic nanopowder of barium titanate was obtained when the precipitate was washed, stoved, and then calcined at 600 ℃ for 1 h. The peroxide precursor of barium titanate and barium titanate nanopowder prepared were characterized to be BaTi(H_2O_2)_2O_3 by TGA-DTA, XRD, TEM, SEM, and XREDS. The peroxide precursor of barium titanate was determined to be BaTi(H_2O_2)_2O_3. The particle size of the barium titanate nanopowder, the calcined product of BaTi(H_2O_2)_2O_3, was in the range of 20-40 nm. A formation mechanism of the barium titanate nanopowder through thermal decomposition of its peroxide precursor was proposed and then validated.

  15. Preparation and properties of yttria doped tetragonal zirconia polycrystal/Sr-doped barium hexaferrite ceramic composites

    International Nuclear Information System (INIS)

    Highlights: • The 3Y-TZP/Sr-doped barium ferrite composites were prepared. • The saturation magnetization was improved by 15% with Sr-doping. • The dispersion coefficient p could reflect the microscopic lattice variation. • The composite with x = 0.5 had the maximum fracture toughness of 8.3 MPa m1/2. - Abstract: The effects of substitution of Ba2+ by Sr2+ on the magnetic property of barium ferrite and addition barium ferrite secondary phase to the 3 mol% yttria-doped tetragonal zirconia polycrystal (3Y-TZP) matrix on the mechanical property of composites were investigated. The Sr-doped barium ferrite (Ba1−xSrxFe12O19, x = 0, 0.25, 0.50 and 0.75) was synthesized by solid-state reaction in advance. Then 3Y-TZP/20 wt% Sr-doped barium ferrite composites were prepared by means of conventional ceramic method. It was found that a moderate amount of Sr added to barium ferrite could boost the saturation magnetization by 15% compared with the composites without Sr-doping. Besides, the composite with x = 0.50 possessed the best mechanical properties, such as 11.5 GPa for Vickers hardness and 8.3 MPa m1/2 for fracture toughness, respectively. It was demonstrated that magnetic and mechanical properties of the composites could be harmonized by the incorporation of barium ferrite secondary phase

  16. Bio-based barium alginate film: Preparation, flame retardancy and thermal degradation behavior.

    Science.gov (United States)

    Liu, Yun; Zhang, Chuan-Jie; Zhao, Jin-Chao; Guo, Yi; Zhu, Ping; Wang, De-Yi

    2016-03-30

    A bio-based barium alginate film was prepared via a facile ionic exchange and casting approach. Its flammability, thermal degradation and pyrolysis behaviors, thermal degradation mechanism were studied systemically by limiting oxygen index (LOI), vertical burning (UL-94), microscale combustion calorimetry (MCC), thermogravimetric analysis (TGA) coupled with Fourier transform infrared analysis (FTIR) and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). It showed that barium alginate film had much higher LOI value (52.0%) than that of sodium alginate film (24.5%). Moreover, barium alginate film passed the UL-94 V-0 rating, while the sodium alginate film showed no classification. Importantly, peak of heat release rate (PHRR) of barium alginate film in MCC test was much lower than that of sodium alginate film, suggested that introduction of barium ion into alginate film significantly decreased release of combustible gases. TG-FTIR and Py-GC-MS results indicated that barium alginate produced much less flammable products than that of sodium alginate in whole thermal degradation procedure. Finally, a possible degradation mechanism of barium alginate had been proposed.

  17. Wideband and enhanced microwave absorption performance of doped barium ferrite

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Pingyuan; Xiong, Kun [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China); Ju, Kui [Guizhou Institute of Metallurgy and Chemical Engineering, Guiyang 550002 (China); Li, Shengnan [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China); Xu, Guangliang, E-mail: xuguangliang@swust.edu.cn [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China)

    2015-07-01

    To achieve stronger microwave attenuation and larger bandwidth in electromagnetic absorber, the nickel ions (Ni{sup 2+}) and manganese ions (Mn{sup 2+}) were employed to partially replace the cobalt ions (Co{sup 2+}) in BaCoTiFe{sub 10}O{sub 19}, and the doped barium hexaferrite (Ba(MnNi){sub 0.2}Co{sub 0.6}TiFe{sub 10}O{sub 19} and Ba(MnNi){sub 0.25}Co{sub 0.5}TiFe{sub 10}O{sub 19}) powders were synthesized via the sol–gel combustion method. Subsequently, the microwave absorbing composites were prepared by mixing the ferrite powders with the paraffin. The X-ray diffraction (XRD) patterns of the doped ferrites confirmed the formation of the M-type barium ferrite, and no other types of barium ferrite could be found. Based on the electromagnetic parameters measured by the vector net-analyzer, it was found that the composite (Ba(MnNi){sub 0.2}Co{sub 0.6}TiFe{sub 10}O{sub 19}) possessed a minimum reflection loss of −52.8 dB at 13.4 GHz with a matching thickness of 1.8 mm and the bandwidth below −15 dB was 5.8 GHz. Moreover, the maximum attenuation of Ba(MnNi){sub 0.25}Co{sub 0.5}TiFe{sub 10}O{sub 19} could reach −69 dB when its thickness was 1.8 mm, and also the bandwidth less than −20 dB was ranging from 13.2 GHz to 18 GHz. Thus, Ba(MnNi){sub 0.2}Co{sub 0.6}TiFe{sub 10}O{sub 19} and Ba(MnNi){sub 0.25}Co{sub 0.5}TiFe{sub 10}O{sub 19} could be the good microwave absorbers, which have great potentials to be applied in the high frequency fields of the microwave absorbing materials. - Highlights: • The Co was first time substituted by Mn–Ni in ferrites. • The substituted ferrites had good microwave absorption. • The doped ferrites had broad bandwidth and low reflection loss.

  18. Barium titanate core – gold shell nanoparticles for hyperthermia treatments

    Directory of Open Access Journals (Sweden)

    FarrokhTakin E

    2013-06-01

    Full Text Available Elmira FarrokhTakin,1,2 Gianni Ciofani,1 Gian Luigi Puleo,1 Giuseppe de Vito,3,4 Carlo Filippeschi,1 Barbara Mazzolai,1 Vincenzo Piazza,3 Virgilio Mattoli1 1Center for Micro-BioRobotics @SSSA, Fondazione Istituto Italiano di Tecnologia, Pontedera, Pisa, Italy; 2The Biorobotics Institute, Scuola Superiore Sant'Anna, Pontedera, Pisa, Italy; 3Center for Nanotechnology Innovation @NEST, Fondazione Istituto Italiano di Tecnologia, Pisa, Italy; 4NEST, Scuola Normale Superiore, Pisa, Italy Abstract: The development of new tools and devices to aid in treating cancer is a hot topic in biomedical research. The practice of using heat (hyperthermia to treat cancerous lesions has a long history dating back to ancient Greece. With deeper knowledge of the factors that cause cancer and the transmissive window of cells and tissues in the near-infrared region of the electromagnetic spectrum, hyperthermia applications have been able to incorporate the use of lasers. Photothermal therapy has been introduced as a selective and noninvasive treatment for cancer, in which exogenous photothermal agents are exploited to achieve the selective destruction of cancer cells. In this manuscript, we propose applications of barium titanate core–gold shell nanoparticles for hyperthermia treatment against cancer cells. We explored the effect of increasing concentrations of these nanoshells (0–100 µg/mL on human neuroblastoma SH-SY5Y cells, testing the internalization and intrinsic toxicity and validating the hyperthermic functionality of the particles through near infrared (NIR laser-induced thermoablation experiments. No significant changes were observed in cell viability up to nanoparticle concentrations of 50 µg/mL. Experiments upon stimulation with an NIR laser revealed the ability of the nanoshells to destroy human neuroblastoma cells. On the basis of these findings, barium titanate core–gold shell nanoparticles resulted in being suitable for hyperthermia treatment

  19. An Integrated Hydrologic Modeling Approach to Cesium-137 Transport in Forested Fukushima Watersheds

    Science.gov (United States)

    Siirila-Woodburn, E. R.; Steefel, C. I.; Williams, K. H.; Birkholzer, J. T.

    2015-12-01

    The 2011 Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in Japan resulted in a significant dissemination of cesium-137 (Cs-137) over a wide area west of the plant, including the contamination of many watersheds and the subsequent evacuation of many communities. Today approximately 90% of on-land Cs-137 fallout following the accident resides in the upper 5 cm of forest soils. While this can be partially attributed to the forested composition of the prefecture (70%), there is also difficulty in cleanup efforts in these regions due to a lack of understanding and predictive capability of radioisotopes transport at the catchment to watershed scale. Subsequently, there is an uncertain, but likely long-term impact on local communities with implications for the use of nuclear energy use worldwide. Due to the complex nature of forest eco-hydrology, sophisticated modeling tools to accurately predict Cs-137 fluxes across different spatial and temporal scales are required. High fidelity, high resolution numerical modeling techniques in conjunction with parallel high performance computing is required to accurately determine transport and feedbacks in these complex systems. To better understand the fundamental transport of Cs-137, a watershed near the FDNPP is modeled with an integrated hydrologic model that includes variably saturated groundwater and overland flow in addition to atmospheric and vegetative processes via a coupled land surface model. Of specific interest is the impact of land cover type on hydrologic flow in the area, which will likely play an important role in erosion patterns and the consequent transport of Cs-137 strongly sorbed to surface soils. Risk management practices (for example, passive remediation versus active remediation such as targeted logging) for two principal tree types (evergreen and deciduous) are informed given the simulated responses to flow patterns assuming different quantities and spatial distribution patterns of each tree type.

  20. 137Cs and 210Po in Pacific Walrus and Bearded Seal from St. Lawrence Island, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, T F; Seagars, D J; Jokela, T; Layton, D

    2005-02-02

    The activity concentration of Cesium-137 ({sup 137}Cs) and naturally-occurring Polonium-210 ({sup 210}Po) were measured in the muscle tissue, kidney and liver of Pacific walrus (Odobenus rosmarus divergens) and bearded seal (Erignathus barbatus) collected by native hunters from the Bering Sea. The mean {sup 137}Cs concentrations in muscle, liver and kidney of Pacific walrus were 0.07, 0.09 and 0.07 Bq kg{sup -1} (N= 5, wet weight), respectively, and 0.17, 0.10, and 0.17 Bq kg{sup -1} (N=2, wet weight), respectively, in bearded seal. In general, {sup 137}Cs tissue concentrations are significantly lower than those previously reported for mammals from other regions. By comparison, {sup 210}Po activity concentrations appear to be higher than those reported elsewhere but a larger variation. The mean {sup 210}Po concentration in the muscle tissue, liver and kidney of Pacific walrus (N=5, wet weight) were 28.7, 189, and 174 Bq kg{sup -1}, respectively. This compares with {sup 210}Po concentration values (N=2, wet weight) of 27, 207, and 68 Bq kg{sup -1} measured in the muscle tissue, liver and kidney, of bearded seal, respectively. Estimated bioaccumulation factors--as defined by the radionuclide concentration ratio between the target tissue to that in sea water--were two to three orders of magnitude higher for {sup 210}Po that those of {sup 137}Cs. We conclude from radiological dose estimates that ingestion of {sup 137}Cs in foods derived from walrus and seal will pose no threat to human health. This work has important implications for assessing health risks to Alaskan coastal communities concerned about the dumping of nuclear waste in the Russia Arctic.

  1. 137Cs and 210Po in Pacific walrus and bearded seal from St. Lawrence Island, Alaska

    International Nuclear Information System (INIS)

    The activity concentration of Cesium-137 (137Cs) and naturally-occurring Polonium-210 (210Po) were measured in the muscle tissue, kidney and liver of Pacific walrus (Odobenus rosmarus divergens) and bearded seal (Erignathus barbatus) collected by native hunters from the Bering Sea during May 1996. The mean 137Cs concentrations in muscle, liver and kidney of Pacific walrus were 0.07, 0.09 and 0.07 Bq kg-1 (n = 5, wet weight), respectively, and 0.17, 0.10, and 0.17 Bq kg-1 (n = 2, wet weight), respectively, in bearded seal. In general, 137Cs tissue concentrations are significantly lower than those previously reported for mammals from other regions. By comparison, 210Po activity concentrations are more variable and appear to be higher level compared with mammal data from other regions. The mean 210Po concentration in the muscle tissue, liver and kidney of Pacific walrus (n = 5, wet weight) were 28.7, 189, and 174 Bq kg-1, respectively. This compares with 210Po concentration values (n = 2, wet weight) of 27, 207 and 68 Bq kg-1 measured in the muscle tissue, liver and kidney, of bearded seal, respectively. Estimated concentration factors-as defined by the radionuclide concentration ratio between the target tissue to that in sea water-were two to three orders of magnitude higher for 210Po that those of 137Cs. We conclude from radiological dose estimates that ingestion of 137Cs in foods derived from walrus and seal will pose no threat to human health. This work has important implications for assessment of risks of Alaskan coastal communities concerned about the dumping of nuclear waste in the Russia Arctic

  2. 137Cs and 210Po in Pacific Walrus and Bearded Seal from St. Lawrence Island, Alaska

    International Nuclear Information System (INIS)

    The activity concentration of Cesium-137 (137Cs) and naturally-occurring Polonium-210 (210Po) were measured in the muscle tissue, kidney and liver of Pacific walrus (Odobenus rosmarus divergens) and bearded seal (Erignathus barbatus) collected by native hunters from the Bering Sea. The mean 137Cs concentrations in muscle, liver and kidney of Pacific walrus were 0.07, 0.09 and 0.07 Bq kg-1 (N= 5, wet weight), respectively, and 0.17, 0.10, and 0.17 Bq kg-1 (N=2, wet weight), respectively, in bearded seal. In general, 137Cs tissue concentrations are significantly lower than those previously reported for mammals from other regions. By comparison, 210Po activity concentrations appear to be higher than those reported elsewhere but a larger variation. The mean 210Po concentration in the muscle tissue, liver and kidney of Pacific walrus (N=5, wet weight) were 28.7, 189, and 174 Bq kg-1, respectively. This compares with 210Po concentration values (N=2, wet weight) of 27, 207, and 68 Bq kg-1 measured in the muscle tissue, liver and kidney, of bearded seal, respectively. Estimated bioaccumulation factors--as defined by the radionuclide concentration ratio between the target tissue to that in sea water--were two to three orders of magnitude higher for 210Po that those of 137Cs. We conclude from radiological dose estimates that ingestion of 137Cs in foods derived from walrus and seal will pose no threat to human health. This work has important implications for assessing health risks to Alaskan coastal communities concerned about the dumping of nuclear waste in the Russia Arctic

  3. Real-time tracking and targeting computations and rocket-vehicle aeroballistics for the PLACES ionospheric-plasma test series

    International Nuclear Information System (INIS)

    The PLACES (Position Location and Communication Effects Simulations) test program, conducted in December 1980 at Eglin Gulf Test Range, involved a series of ionospheric releases of barium/barium-nitrate vapor. The Defense Nuclear Agency sponsored program investigated effects of a structured ionospheric plasma (similar to that produced by a high-altitude nuclear explosion) on satellite navigation systems and provided in situ measurement of plasma structure. Terrier-Tomahawk rocket systems boosted the barium payloads, beacon payloads (plasma occultation experiment), and probe payloads (plasma in situ measurement). Drifting plasma tracking procedures, beacon-and probe-vehicle targeting procedures, and vehicle flight test results are presented

  4. A Comparative Study on Magnetostructural Properties of Barium Hexaferrite Powders Prepared by Polyethylene Glycol

    Directory of Open Access Journals (Sweden)

    Zehra Durmus

    2014-01-01

    Full Text Available Nanocrystalline particles of barium hexaferrite were synthesized by a sol-gel combustion route using nitrate-citrate gels prepared from metal nitrates and citric acid solutions with Fe/Ba molar ratio 12. The present paper aims to study the effect of addition of polyethylene glycol (PEG solutions with different molecular weights (MW: 400, 2000, and 10.000 g/mol on magnetostructural properties of barium hexaferrite. The formation of the barium hexaferrite was inspected using X-ray diffraction (XRD analysis, Fourier transform infrared (FT-IR analysis, thermogravimetric (TGA analysis, scanning electron microscopy (SEM analysis and vibrating sample magnetometer (VSM analysis for magnetic measurements.

  5. Microscopic insight into nuclear structure properties of proton-rich barium isotopes

    International Nuclear Information System (INIS)

    Variation after projection (VAP) calculations with Hartree-Bogoliubov (HB) Ansatz have been carried out for A=120-136 barium isotopes. In this framework, the yrast spectra with Jmaxπ=10+, B(E2) transition probabilities, quadrupole (β2) and hexadecapole (β4) deformation parameters for even-even barium isotopes have been obtained. The results of the calculation give an indication that it is important to include the hexadecapole-hexadecapole component of the two-body interaction for obtaining various nuclear structure quantities in these barium isotopes. (author)

  6. Application of barium fluoride for sulfur selective extraction at X-ray spectroscopic analysis of steel

    International Nuclear Information System (INIS)

    In order to increase the sensitivity of X-ray spectroscopic identification of sulphur in steels the application of barium fluoride for selective extraction of sulphate ions was proposed by authors of present work. The influence of concentration of sulphate ions, iron, nickel, chromium and titanium cations as well as acidity of solutions on the coefficient of distribution of sulphate ions in the system barium fluoride-water was studied. The distribution coefficients were calculated, the completeness of extraction was calculated as well. It is defined that sulphate ions from solutions containing cations of heavy metals and other anions can be extracted by means of barium fluoride.

  7. Barium ferrite nanoparticles prepared by self-propagating low-temperature combustion method and its characterization

    Indian Academy of Sciences (India)

    P M Prithviraj Swamy; S Basavaraja; Vijayanand Havanoor; N V Srinivas Rao; R Nijagunappa; A Venkataraman

    2011-12-01

    The barium ferrite particles were prepared using a self-propagating low-temperature combustion method using polyethylene glycol (PEG) as a fuel. The process was investigated with simultaneous thermogravimetric-differential thermal analysis (TG–DTA). The crystalline structure, morphology and the magnetic properties of the barium ferrite particles were studied by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and SQUID susceptometer. The results show that the ignition temperature of PEG is lower compared with other combustion methods and gives nanocrystalline barium ferrite.

  8. Preparation and Characterization of Nano-particle Substituted Barium Hexaferrite

    CERN Document Server

    Atassi, Yomen; Tally, Mohammad

    2014-01-01

    High density magnetic recording requires high coercivity magnetic media and small particle size. Barium hexaferrite has been considered as a leading candidate material because of its chemical stability, fairly large crystal anisotropy and suitable magnetic characteristics. In this work, we present the preparation of the hexagonal ferrite BaFe12O19 and one of its derivative; the Zn-Sn substituted hexaferrite by the chemical co-precipitation method. The main advantage of this method on the conventional glass-ceramic one, resides in providing a small enough particle size for magnetic recording. We demonstrate using the X-ray diffraction patterns that the particle size decreases when substituting the hexaferrite by the Zn-Sn combination. This may improve the magnetic properties of the hexaferrite as a medium for HD magnetic recording

  9. Stark effect in Rydberg states of helium and barium

    International Nuclear Information System (INIS)

    This thesis, which deals with the effect of an electric field up to moderate field strengths on atoms with two valence electrons outside closed shells, in casu helium and barium, contains chapter in which the linear Stark effect in the 1 snp 1,3p Rydberg states of helium (n around 40) has been studied in a CW laser-atomic beam experiment. The evolution of the angular momentum manifolds into the n-mixing regime was followed and avoided level crossings were observed. Stark manifolds were also calculated by diagonalization of the complete energy matrix in the presence of an electric field. It turned out to be necessary to include up to five n-values in the calculations already at moderate values of the field to reproduce the data within the experimental accuracy (a few MHz), especially in the regime of the avoided crossings. (author). 147 refs.; 30 figs.; 8 tabs

  10. Effect of Nb on barium titanate prepared from citrate solutions

    Directory of Open Access Journals (Sweden)

    Stojanović Biljana D.

    2002-01-01

    Full Text Available The influence of the addition of dopants on the microstructure development and electrical properties of BaTiO3 doped with 0.2, 0.4, 0.6, 0.8 mol% of Nb and 0.01 mol% of Mn based compounds was studied. Doped barium titanate was prepared using the polymeric precursor method from citrate solutions. The powders calcined at 700°C for 4 hours were analysed by infrared (IR spectroscopy to verify the presence of carbonates, and by X-ray diffraction (XRD for phase formation. The phase composition, microstructure and dielectric properties show a strong dependence on the amount of added niobium.

  11. Optical-induced absorption tunability of Barium Strontium Titanate film

    Science.gov (United States)

    Luo, Chunya; Ji, Jie; Yue, Jin; Rao, Yunkun; Yao, Gang; Li, Dan; Zeng, Ying; Li, Renkui; Xiao, Longsheng; Liu, Xinxing; Yao, Jianquan; Ling, Furi

    2016-10-01

    The absorption tunability of 100 nm thickness of ferroelectric Barium Strontium Titanate (Ba0.5Sr0.5TiO3) thin films with different densities of pumped optical field is measured by terahertz time-domain spectroscopy in the range of 0.2 THz - 1.2 THz at 19 °C. Experimental results show that the absorption coefficient of BST film is approximately at 5000 cm-1-20000 cm-1 in the range of 0.2 THz - 1.2 THz and the absorption coefficient reached up to 16% when we applied the optical field up to 600 mW. The theoretical calculations reveal that increasing photoexcitation fluences is responsible for the increasing of transmission change in the conduction current density cause the absorption coefficient varied.

  12. Infrared Spectroscopic Characterization of Calcium and Barium Hydrazone Complexes

    Directory of Open Access Journals (Sweden)

    *A. Adeniyi

    2013-06-01

    Full Text Available Hydrazones have attracted considerable interest on account of their biological activities. Introduction of calcium and barium metal ions into m- and p-nitrobenzoic hydrazones is expected to modify these biological properties for enhanced activity and versatility. The ligands were synthesized from the parent acids. The complexes have been characterized using C, H and N microanalyses and IR spectrometry. The IR spectral data of the ligands and complexes revealed bonding via the C=O and C=N groups. The suggested metal to ligand stoichiometries are: [M (m-NBHx]Cl2.yH2O, x, y = 1 and 4 for M = Ca; x, y = 2 and 3 for M = Ba respectively. [M(p-NBHx]Cl2.yH2O, x, y = 1 and 12 for M = Ca; x, y = 1 and 3 for M = Ba respectively. The structural deductions are tentative pending future X-ray structural studies.

  13. Nonlinear optical properties of calcium barium niobate epitaxial thin films.

    Science.gov (United States)

    Bancelin, Stéphane; Vigne, Sébastien; Hossain, Nadir; Chaker, Mohammed; Légaré, François

    2016-07-25

    We investigate the potential of epitaxial calcium barium niobate (CBN) thin film grown by pulsed laser deposition for optical frequency conversion. Using second harmonic generation (SHG), we analyze the polarization response of the generated signal to determine the ratios d15 / d32 and d33 / d32 of the three independent components of the second-order nonlinear susceptibility tensor in CBN thin film. In addition, a detailed comparison to the signal intensity obtained in a y-cut quartz allows us to measure the absolute value of these components in CBN thin film: d15 = 5 ± 2 pm / V, d32 = 3.1 ± 0.6 pm / V and d33 = 9 ± 2 pm / V. PMID:27464195

  14. Pulsating aurora induced by upper atmospheric barium releases

    Science.gov (United States)

    Deehr, C.; Romick, G.

    1977-01-01

    The paper reports the apparent generation of pulsating aurora by explosive releases of barium vapor near 250 km altitude. This effect occurred only when the explosions were in the path of precipitating electrons associated with the visible aurora. Each explosive charge was a standard 1.5 kg thermite mixture of Ba and CuO with an excess of Ba metal which was vaporized and dispersed by the thermite explosion. Traces of Sr, Na, and Li were added to some of the charges, and monitoring was achieved by ground-based spectrophotometric observations. On March 28, 1976, an increase in emission at 5577 A and at 4278 A was observed in association with the first two bursts, these emissions pulsating with roughly a 10 sec period for approximately 60 to 100 sec after the burst.

  15. Bronchography in dogs. Comparative study with two barium sulphate solutions

    International Nuclear Information System (INIS)

    Two solutions of barium sulphate, 60 and 30% w/v, were compared with the ''overflow'' Bronchographic method. Two groups of eight healthy adult does of both sexes, weighing 7 to 18 kg were used for the study. The dogs were anaesthetised with thiopentone sodium 2% (20 mg/kg iv). After intubation, each dog received contrast medium by a catheter connected to a syringe, in a 9 mi dose. Two series of two x-rays plates were taken in left lateral recumbent, 3 and 6 min after administering the contrast medium and in ventrodorsal projection, 30 sec. later. The x-ray plates obtained were analysed and compared intra and inter group considering the advance speed of the contrast medium, the radiographic density and outlines. Adverse reactions were controlled

  16. Structural and functional characterization of barium zirconium titanate / epoxy composites

    Directory of Open Access Journals (Sweden)

    Filiberto González Garcia

    2011-12-01

    Full Text Available The dielectric behavior of composite materials (barium zirconium titanate / epoxy system was analyzed as a function of ceramic concentration. Structure and morphologic behavior of the composites was investigated by X-ray Diffraction (XRD, Fourier transformed infrared spectroscopy (FT-IR, Raman spectroscopy, field emission scanning electron microscopy (FE-SEM and transmission electron microscopy (TEM analyses. Composites were prepared by mixing the components and pouring them into suitable moulds. It was demonstrated that the amount of inorganic phase affects the morphology of the presented composites. XRD revealed the presence of a single phase while Raman scattering confirmed structural transitions as a function of ceramic concentration. Changes in the ceramic concentration affected Raman modes and the distribution of particles along into in epoxy matrix. Dielectric permittivity and dielectric losses were influenced by filler concentration.

  17. Synthesis and optical study of barium magnesium aluminate blue phosphors

    Energy Technology Data Exchange (ETDEWEB)

    Jeet, Suninder, E-mail: suninder.jeet@thapar.edu; Pandey, O. P., E-mail: oppandey@thapar.edu [School of Physics and Materials Science, Thapar University, Patiala (147003), Punjab (India); Sharma, Manoj, E-mail: manojnarad@sggswu.org [Department of Nanotechnology, Sri Guru Granth Sahib World University, Fatehgarh Sahib(146406), Punjab (India)

    2015-05-15

    Europium doped barium magnesium aluminate (BaMgAl{sub 10}O{sub 17}:Eu{sup 2+}) phosphor was prepared via solution combustion method at 550°C using urea as a fuel. Morphological and optical properties of the prepared sample was studied by X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Photoluminescence spectroscopy (PL). XRD result showed the formation of pure phase BaMgAl{sub 10}O{sub 17}(JCPDS 26-0163) along with an additional phase BaAl{sub 2}O{sub 4}(JCPDS 01-082-1350). TEM image indicated the formation of faceted particles with average particle size 40 nm. From PL spectra, a broad emission band obtained at about 450 nm attributes to 4f{sup 6} 5d → 4f{sup 7} transition of Eu{sup 2+} which lies in the blue region of the visible spectrum.

  18. Study on a flexoelectric microphone using barium strontium titanate

    Science.gov (United States)

    Kwon, S. R.; Huang, W. B.; Zhang, S. J.; Yuan, F. G.; Jiang, X. N.

    2016-04-01

    In this study, a flexoelectric microphone was, for the first time, designed and fabricated in a bridge structure using barium strontium titanate (Ba0.65Sr0.35TiO3) ceramic and tested afterwards. The prototyped flexoelectric microphone consists of a 1.5 mm  ×  768 μm  ×  50 μm BST bridge structure and a silicon substrate with a cavity. The sensitivity and resonance frequency were designed to be 0.92 pC/Pa and 98.67 kHz, respectively. The signal to noise ratio was measured to be 74 dB. The results demonstrate that the flexoelectric microphone possesses high sensitivity and a wide working frequency range simultaneously, suggesting that flexoelectricity could be an excellent alternative sensing mechanism for microphone applications.

  19. Polymorphisms in MIR137HG and microRNA-137-regulated genes influence gray matter structure in schizophrenia.

    Science.gov (United States)

    Wright, C; Gupta, C N; Chen, J; Patel, V; Calhoun, V D; Ehrlich, S; Wang, L; Bustillo, J R; Perrone-Bizzozero, N I; Turner, J A

    2016-02-02

    Evidence suggests that microRNA-137 (miR-137) is involved in the genetic basis of schizophrenia. Risk variants within the miR-137 host gene (MIR137HG) influence structural and functional brain-imaging measures, and miR-137 itself is predicted to regulate hundreds of genes. We evaluated the influence of a MIR137HG risk variant (rs1625579) in combination with variants in miR-137-regulated genes TCF4, PTGS2, MAPK1 and MAPK3 on gray matter concentration (GMC). These genes were selected based on our previous work assessing schizophrenia risk within possible miR-137-regulated gene sets using the same cohort of subjects. A genetic risk score (GRS) was determined based on genotypes of these four schizophrenia risk-associated genes in 221 Caucasian subjects (89 schizophrenia patients and 132 controls). The effects of the rs1625579 genotype with the GRS of miR-137-regulated genes in a three-way interaction with diagnosis on GMC patterns were assessed using a multivariate analysis. We found that schizophrenia subjects homozygous for the MIR137HG risk allele show significant decreases in occipital, parietal and temporal lobe GMC with increasing miR-137-regulated GRS, whereas those carrying the protective minor allele show significant increases in GMC with GRS. No correlations of GMC and GRS were found in control subjects. Variants within or upstream of genes regulated by miR-137 in combination with the MIR137HG risk variant may influence GMC in schizophrenia-related regions in patients. Given that the genes evaluated here are involved in protein kinase A signaling, dysregulation of this pathway through alterations in miR-137 biogenesis may underlie the gray matter loss seen in the disease.

  20. Barium and carbon fluxes in the Canadian Arctic Archipelago

    Science.gov (United States)

    Thomas, Helmuth; Shadwick, Elizabeth; Dehairs, Frank; Lansard, Bruno; Mucci, Alfonso; Navez, Jacques; Gratton, Yves; Prowe, Friederike; Chierici, Melissa; Fransson, Agneta; Papakyriakou, Tim N.; Sternberg, Erika; Miller, Lisa A.; Tremblay, Jean-ÉRic; Monnin, Christophe

    2011-09-01

    The seasonal and spatial variability of dissolved Barium (Ba) in the Amundsen Gulf, southeastern Beaufort Sea, was monitored over a full year from September 2007 to September 2008. Dissolved Ba displays a nutrient-type behavior: the maximum water column concentration is located below the surface layer. The highest Ba concentrations are typically observed at river mouths, the lowest concentrations are found in water masses of Atlantic origin. Barium concentrations decrease eastward through the Canadian Arctic Archipelago. Barite (BaSO4) saturation is reached at the maximum dissolved Ba concentrations in the subsurface layer, whereas the rest of the water column is undersaturated. A three end-member mixing model comprising freshwater from sea-ice melt and rivers, as well as upper halocline water, is used to establish their relative contributions to the Ba concentrations in the upper water column of the Amundsen Gulf. Based on water column and riverine Ba contributions, we assess the depletion of dissolved Ba by formation and sinking of biologically bound Ba (bio-Ba), from which we derive an estimate of the carbon export production. In the upper 50 m of the water column of the Amundsen Gulf, riverine Ba accounts for up to 15% of the available dissolved Ba inventory, of which up to 20% is depleted by bio-Ba formation and export. Since riverine inputs and Ba export occur concurrently, the seasonal variability of dissolved Ba in the upper water column is moderate. Assuming a fixed organic carbon to bio-Ba flux ratio, carbon export out of the surface layer is estimated at 1.8 ± 0.45 mol C m-2 yr-1. Finally, we propose a climatological carbon budget for the Amundsen Gulf based on recent literature data and our findings, the latter bridging the surface and subsurface water carbon cycles.

  1. Brillouin function characteristics for La-Co substituted barium hexaferrites

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chuanjian, E-mail: wcjuestc2005@gmail.com, E-mail: ksun@uestc.edu.cn; Yu, Zhong; Sun, Ke, E-mail: wcjuestc2005@gmail.com, E-mail: ksun@uestc.edu.cn; Guo, Rongdi; Jiang, Xiaona; Lan, Zhongwen [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Yang, Yan [Department of Communication and Engineering, Chengdu Technological University, Chengdu 611730 (China)

    2015-09-14

    La-Co substituted barium hexaferrites with the chemical formula of Ba{sub 1−x}La{sub x}Fe{sub 12−x}Co{sub x}O{sub 19} (x = 0.0, 0.1, 0.3, and 0.5), prepared by a conventional ceramic method, were systematically investigated by Raman spectra, X-ray photoelectron spectroscopy, Rietveld refinement of X-ray diffraction patterns, and vibrating sample magnetometer. The result manifests that all the compounds are crystallized in magnetoplumbite hexagonal structure. Trivalent cobalt ions prevailingly occupy the 2a, 4f{sub 1}, and 12k sites. According to Néel model of collinear-spin ferrimagnetism, the molecular-field coefficients ω{sub bf2}, ω{sub kf1}, ω{sub af1}, ω{sub kf2}, and ω{sub bk} of La-Co substituted barium hexaferrites have been calculated using the nonlinear fitting method, and the magnetic moment of five sublattices (2a, 2b, 4f{sub 1}, 4f{sub 2}, and 12k) versus temperature T has been also investigated. The fitting results are coincided well with the experimental data. Moreover, with the increase of La-Co substitution amount x, the molecular-field coefficients ω{sub bf2} and ω{sub af1} decrease constantly, while the molecular-field coefficients ω{sub kf1}, ω{sub kf2}, and ω{sub bk} show a slight change.

  2. CD137-mediated immunotherapy for allergic asthma

    OpenAIRE

    Polte, Tobias; Foell, Juergen; Werner, Christoph; Hoymann, Heinz-Gerd; Braun, Armin; Burdach, Stefan; Mittler, Robert S.; Hansen, Gesine

    2006-01-01

    The prevalence of asthma continues to increase. Asthma is caused by a Th2 cell–driven immune response. Its optimal treatment remains a challenge, and a sufficient immunotherapeutic approach to treating asthma has yet to be found. Using a murine asthma model, we show that a single injection of an anti-CD137 (4-1BB) mAb prevents the development of airway hyperreactivity, eosinophilic airway inflammation, excessive mucus production, and elevated IgE during the observation period of 7 weeks. Most...

  3. Research on fabricating technique of Ba-Al-S:Eu sputtering target

    Institute of Scientific and Technical Information of China (English)

    DING Zhao; YU Zhinong; ZHANG Dongpu; XUE Wei; WANG Wuyu

    2009-01-01

    Ba-Al-S-Eu sputtering target for blue emitting phosphors was prepared by powder sintering method. XRD patterns showed that the main components of the target were barium tetra aluminum sulfide (BaAl4S7), bariutm sulfide (BaS), and europium sulfide (EuS). In the samples, part of the barium and aluminum are formed into barium aluminum oxide (BaAl2O4) with the impurity element of oxygen. The PL characteristic spectra of the target showed the 470 nm blue emission obviously, and the Ba-Al-S thin films also transmitted a purple-blue emission at the position of 440 nm.The results indicated that this method was suitable for the fabrication of the Ba-Al-S:Eu sputtering target.

  4. Characterization and growth dynamics of barium titanate crystallite on nanometer scale

    Institute of Scientific and Technical Information of China (English)

    Sen Wang; Yue Zhang; Zhen Ji; Yousong Gu; Yunhua Huang; Cheng Zhou

    2005-01-01

    Barium titanate powder on nanometer scale was synthesized by means of co-precipitation. The thermal mass loss, crystal grain growth and phase transition of the barium titanate nanometer powder were investigated by TG (Thermogravimetric)-DTA (Differential scanning calorimetric) and XRD (X-ray powder diffractometer) at different heat treatment temperatures. The results show that amorphous barium titanate powder can transfer into tetragonal symmetry structure after heat treatment. When the heat treatment temperature is below 900℃, the grains grow rapidly because the activation energy at low temperature is greatly less than that at high temperature. By controlling theheat treatment temperature, the optimization of the barium titanate crystallite size and formation of tetragonal phase can be realized.

  5. A study of magneto-crystalline alignment in sintered barium hexaferrite fabricated by powder injection molding

    Energy Technology Data Exchange (ETDEWEB)

    Zlatkov, B.S. [FOTEC Forschungs- und Technologietransfer GmbH, Viktor Kaplan-Strasse 2, 2700 Wiener Neustadt (Austria); Nikolic, M.V. [Institute for Multidisciplinary Research, Kneza Viseslava 1, 11000 Beograd (Serbia)], E-mail: mariavesna@cms.bg.ac.yu; Aleksic, O. [Institute for Multidisciplinary Research, Kneza Viseslava 1, 11000 Beograd (Serbia); Danninger, H.; Halwax, E. [Institute of Chemical Technologies and Analytics, Getreidemarkt 9/164, 1060 Wien (Austria)

    2009-02-15

    Barium hexaferrite permanent magnets were produced by powder injection molding. Starting barium hexaferrite powder was prepared from a Fe{sub 2}O{sub 3} and BaCO{sub 3} powder mixture by calcination followed by milling. The feedstock for powder injection molding was prepared by mixing barium hexaferrite powder with a low viscosity binder. Magnetic alignment was achieved by applying a high intensity magnetic field to the melted feedstock during the injection process. Green samples (with and without magnetic alignment) were subjected to solvent debinding and subsequent thermal debinding followed by sintering. Sintering conditions were optimized in order to achieve a maximum energy product value. Magneto-crystalline aligning in barium hexaferrite was studied on both green and sintered samples using X-ray diffraction, scanning electron microscope (SEM) and magnetic measurements (hysteresisgraphs). All measurements were made both in a parallel and perpendicular direction to the aligning magnetic field. The obtained results confirmed magneto-crystalline alignment.

  6. Study of the immunoisolating effects of barium-alginate microencapsulation on rat islets allograft survival

    Institute of Scientific and Technical Information of China (English)

    Mei Zhang; Chao Liu; Cuiping Liu; Youwen Qin; Zhaosun Zhen

    2005-01-01

    Objective: To evaluate the immunoisolating effects of barium-alginate microencapsulation on islets allograft survival. Methods: The nonmicroencapsulated and microencapsulated islets were transplanted under the kidney capsule or intraperitoneally into Wistar rat with STZ-induced diabetes. The blood glucose and insulin secretion of grafts were observed. Graft function was tested by oral rats was associated with normal glucose and insulin profiles in response to OGTT. Conclusion: Microencapsulation with barium-alginate membrane can prolong islet survival and protect islets against allorejection.

  7. Kinetics of barium sulphate reaction crystallization in crystallizers with internal circulation

    OpenAIRE

    Koralewska, J.; Piotrowski, K; B. Wierzbowska; A. Matynia

    2008-01-01

    Kinetic calculation results describing the observed nucleation and growth rates of barium sulphate crystals precipitated in an integrated reaction-crystallization process in a barium sulphate-ammonium chloride-water system are presented and analyzed. The scope of experiments included two continuous model DTM-type crystallizers (Draft Tube Magma) with internal circulation of the suspension forced by a liquid jet-pump device responsible for stable and intensive enough ascending/descending flow ...

  8. Impact of Biofield Treatment on Atomic and Structural Characteristics of Barium Titanate Powder

    OpenAIRE

    Trivedi, Mahendra; Nayak, Gopal

    2015-01-01

    Barium titanate, perovskite structure is known for its high dielectric constant and piezoelectric properties, which makes it interesting material for fabricating capacitors, transducer, actuator, and sensors. The perovskite crystal structure and lattice vibrations play a crucial role in its piezoelectric and ferroelectric behavior. In the present study, the barium titanate powder was subjected to biofield treatment. Further, the control and treated samples were characterized using X-ray diffr...

  9. Screening of plant species for phytoremediation of uranium, thorium, barium, nickel, strontium and lead contaminated soils from a uranium mill tailings repository in South China.

    Science.gov (United States)

    Li, Guang-yue; Hu, Nan; Ding, De-xin; Zheng, Ji-fang; Liu, Yu-long; Wang, Yong-dong; Nie, Xiao-qin

    2011-06-01

    The concentrations of uranium, thorium, barium, nickel, strontium and lead in the samples of the tailings and plant species collected from a uranium mill tailings repository in South China were analyzed. Then, the removal capability of a plant for a target element was assessed. It was found that Phragmites australis had the greatest removal capabilities for uranium (820 μg), thorium (103 μg) and lead (1,870 μg). Miscanthus floridulus had the greatest removal capabilities for barium (3,730 μg) and nickel (667 μg), and Parthenocissus quinquefolia had the greatest removal capability for strontium (3,920 μg). In this study, a novel coefficient, termed as phytoremediation factor (PF), was proposed, for the first time, to assess the potential of a plant to be used in phytoremediation of a target element contaminated soil. Phragmites australis has the highest PFs for uranium (16.6), thorium (8.68), barium (10.0) and lead (10.5). Miscanthus floridulus has the highest PF for Ni (25.0). Broussonetia papyrifera and Parthenocissus quinquefolia have the relatively high PFs for strontium (28.1 and 25.4, respectively). On the basis of the definition for a hyperaccumulator, only Cyperus iria and Parthenocissus quinquefolia satisfied the criteria for hyperaccumulator of uranium (36.4 μg/g) and strontium (190 μg/g), and could be the candidates for phytoremediation of uranium and strontium contaminated soils. The results show that the PF has advantage over the hyperaccumulator in reflecting the removal capabilities of a plant for a target element, and is more adequate for assessing the potential of a plant to be used in phytoremediation than conventional method.

  10. 21 CFR 137.250 - White corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false White corn meal. 137.250 Section 137.250 Food and... Related Products § 137.250 White corn meal. (a) White corn meal is the food prepared by so grinding... fiber content of the finished corn meal is not less than 1.2 percent and not more than that of...

  11. 21 CFR 137.255 - Bolted white corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Bolted white corn meal. 137.255 Section 137.255... Flours and Related Products § 137.255 Bolted white corn meal. (a) Bolted white corn meal is the food... of the finished bolted white corn meal does not exceed by more than 0.3 percent the fat content...

  12. Synthesis of nonstoichiometric M-type barium ferrite nanobelt by spark plasma sintering method

    Institute of Scientific and Technical Information of China (English)

    ZHAO Wenyu; ZHANG Qingjie; TANG Xinfeng; CHENG Haibin

    2005-01-01

    This study investigated the feasibility of ultrafast crystallization of M-type barium ferrite when the coprecipitation precursors in stoichiometric proportions as BaFe12O19, Fe(OH)3 and BaCO3 nanoparticles, had been heated by spark plasma sintering (SPS) process. The results show that SPS method may realize the ultrafast crystallization of M-type barium ferrite, absolutely prevent the crystallization of intermediate phase α-Fe2O3, and significantly decrease the crystallization temperature of M-type barium ferrite. The sintered samples obtained at 800℃ by sintering the precursors for 10 minutes are a kind of multiphase ferrites composed of major phase M-type barium ferrite and trace amount of BaFe0.24Fe0.76O2.88. It is discovered that M-type barium ferrites in the holes of the sintered samples are in nanobelt microstructure about 100-300 nm in width and several micrometers in length. These M-type barium ferrite nanobelts are non-stoichiometric and may be expressed as BaFe12+Xo19+1.5x (-4.77≤x≤6.50). Their composistions suggest completely random Fe-rich or Ba-rich domains.

  13. Barium swallow study in routine clinical practice: a prospective study in patients with chronic cough

    Directory of Open Access Journals (Sweden)

    Carlos Shuler Nin

    2013-12-01

    Full Text Available OBJECTIVE: To assess the routine use of barium swallow study in patients with chronic cough.METHODS: Between October of 2011 and March of 2012, 95 consecutive patients submitted to chest X-ray due to chronic cough (duration > 8 weeks were included in the study. For study purposes, additional images were obtained immediately after the oral administration of 5 mL of a 5% barium sulfate suspension. Two radiologists systematically evaluated all of the images in order to identify any pathological changes. Fisher's exact test and the chi-square test for categorical data were used in the comparisons.RESULTS: The images taken immediately after barium swallow revealed significant pathological conditions that were potentially related to chronic cough in 12 (12.6% of the 95 patients. These conditions, which included diaphragmatic hiatal hernia, esophageal neoplasm, achalasia, esophageal diverticulum, and abnormal esophageal dilatation, were not detected on the images taken without contrast. After appropriate treatment, the symptoms disappeared in 11 (91.6% of the patients, whereas the treatment was ineffective in 1 (8.4%. We observed no complications related to barium swallow, such as contrast aspiration.CONCLUSIONS: Barium swallow improved the detection of significant radiographic findings related to chronic cough in 11.5% of patients. These initial findings suggest that the routine use of barium swallow can significantly increase the sensitivity of chest X-rays in the detection of chronic cough-related etiologies.

  14. Surface erosion assessment in New Zealand using caesium-137

    International Nuclear Information System (INIS)

    The 137Cs technique has provided the first quantitative, medium-term data on rates of soil redistribution by surface erosion on both cropland and rangeland in New Zealand. Research has also provided data on natural short-range variability of 137Cs in uneroded soils, and a technique for independently estimating 137Cs input values from rainfall. The greatest research need remains the development of robust, accurate calibration procedures for converting 137Cs measurements to rates of erosion. Emphasis has been on application of the technique to provide field-based data on erosion rates, with limited research to further develop the technique. This paper summarises recent research in these two areas

  15. Excess Barium as a Paleoproductivity Proxy: A Reevaluation

    Science.gov (United States)

    Eagle, M.; Paytan, A.

    2001-12-01

    Marine barite may serve as a proxy to reconstruct past export production (Dymond, 1992). In most studies sedimentary barite accumulation is not measured directly, instead a parameter termed excess barium (Baexs), also referred to as biogenic barium, is used to estimate the barite content. Baexs is defined as the total Ba concentration in the sediment minus the Ba associated with terrigenous material. Baexs is calculated by normalization to a constant Ba/Al ratio, typically the average shale ratio. This application assumes that (1) all the Ba besides the fraction associated with terrigenous Al is in the form of barite (the phase related to productivity) (2) the Ba/Alshale is constant in space and time (3) all of the Al is associated with terrigenous matter. If these assumptions are invalidated however, this approach lead to significant errors in calculating export production rates. To test the validity of the use of Baexs as a proxy for barite we compared the Baexs in a wide range of core top sediments from different oceanic settings to the barite content in the same cores. We found that Baexs frequently overestimated the Ba fraction associated with barite and in several cases significant Baexs was measured in the cores where no barite was observed. We have also used a sequential leaching protocol (Collier and Edmond 1984) to determine Ba association with organic matter, carbonates, Fe-Mn hydroxides and silicates. While terrigenous Ba remains an important fraction, in our samples 25-95% of non-barite Ba was derived from other fractions, with Fe-Mn oxides contributing the most Ba. In addition we found that the Ba/Al ratio in the silicate fraction of our samples varied considerably from site to site. The above results suggest that at least two of the underlying assumptions for employing Baexs to reconstruct paleoproductivity are not always valid and previously published data from (Murray and Leinen 1993) indicate that the third assumption may also not hold in every

  16. Enthalpy of formation of (In, Gd)-doped barium cerate

    Energy Technology Data Exchange (ETDEWEB)

    Matskevich, N.I., E-mail: nata.matskevich@yandex.ru [Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk (Russian Federation); Karlsruhe Institute of Technology, Institute of Solid State Physics, D-76334 Karlsruhe (Germany); Wolf, Th. [Karlsruhe Institute of Technology, Institute of Solid State Physics, D-76334 Karlsruhe (Germany); Adelmann, P.; Semerikova, A.N.; Anyfrieva, O.I. [Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk (Russian Federation)

    2015-09-10

    Highlights: • BaCe{sub 0.7}Gd{sub 0.2}In{sub 0.1}O{sub 2.85} was prepared by solid-state reaction. • The standard formation enthalpy was determined. • The stabilization energy (Δ{sub st}H°) was calculated. • Δ{sub st}H° of BaCe{sub 0.7}Gd{sub 0.2}In{sub 0.1}O{sub 2.85} is higher than BaCe{sub 0.7}Nd{sub 0.2}In{sub 0.1}O{sub 2.85} and BaCeO{sub 3}. - Abstract: Solution enthalpies of barium cerate doped by gadolinium and indium and a mixture of BaCl{sub 2} + 0.7CeCl{sub 3} + 2GdCl{sub 3} + 0.1InCl{sub 3} have been measured in 1 mol dm{sup −3} HCl with 0.1 mol dm{sup −3} KI. For the first time the standard molar formation enthalpy of BaCe{sub 0.7}Gd{sub 0.2}In{sub 0.1}O{sub 2.85} has been determined by solution calorimetry as follows: Δ{sub f}H° (298.15 K) = −1615.84 ± 9.01 kJ mol{sup −1}. The stabilization energy for above-mentioned compound has been calculated as well. It has been shown that barium cerate doped gadolinium and indium has higher stabilization energy than BaCe{sub 0.7}Nd{sub 0.2}In{sub 0.1}O{sub 2.85} and BaCeO{sub 3}. The reaction enthalpy with CO{sub 2} interaction has been calculated for BaCe{sub 0.7}Gd{sub 0.2}In{sub 0.1}O{sub 2.85}.

  17. Mechanisms of 137Cs migration in coniferous forest soils

    International Nuclear Information System (INIS)

    Field and laboratory studies demonstrate two processes involved in 137Cs migration in coniferous forest soil. The data illustrate that the effects of leaching and litter accumulation combine, over the time interval since deposition, to achieve the observed distribution of 137Cs in the soil profile. Today, under normal field conditions the rate of 137Cs leaching from forest humus is low and even extreme environmental conditions do not increase greatly the extent of 137Cs mobilisation by leaching. A three-phase model of 137Cs migration in the organic horizons of coniferous forest soils is proposed. The phases are discrete but at any point in time the behaviour of some portion of deposited 137Cs will be characteristic of one of the three phases. In the first phase 137Cs intercepted by the canopy is washed to the forest floor where a proportion (20-40% is reported) rapidly percolates through the organic horizons reaching the underlying soil; the remainder is retained in the organic horizons. In the second phase, which our study estimates to last about 5 years, the 137Cs contained within the Ol and Of horizons moves to the Oh horizon. Accumulation of relatively uncontaminated litter on top of the Ol horizon contributes to this migration, while 137Cs mobilised from the Ol and Of horizons by decomposition is leached to the Oh horizon. The 137Cs which reaches the Oh horizon, either by leaching or by decomposition and burial, enters the third phase in which the pace of migration is greatly reduced. Decomposition is slowest in the Oh horizon and the accumulation and turnover of Oh material is also very slow. At the site investigated in this study the bulk of the deposited 137Cs is in this third phase and we suggest that this phase will persist for many years to come

  18. Mechanism of Phase Transformation and Formation of Barium Hexaferrite Doped with Rare-Earths in Sol-Gel Process

    Institute of Scientific and Technical Information of China (English)

    甘树才; 洪广言; 张军; 车平; 唐娟

    2003-01-01

    The phase-transformation in sol-gel preparation of barium hexaferrite and the formation of barium hexaferrite doped with La3+ were studied by chemical phase analysis, X-ray diffraction and infrared spectrometry analysis. The experimental results show that phase transformation reactions of FeCO3, Fe2O3 and BaFe2O4, barium hexaferrite and γ-Fe2O3 take place in the heat treatment of gel. While the doping lanthanide ion replace barium ion, an equivalent quantity of Fe3+ are reduced to Fe2+ to maintain the charge equilibrium.

  19. Barium oxide, calcium oxide, magnesia, and alkali oxide free glass

    Science.gov (United States)

    Lu, Peizhen Kathy; Mahapatra, Manoj Kumar

    2013-09-24

    A glass composition consisting essentially of about 10-45 mole percent of SrO; about 35-75 mole percent SiO.sub.2; one or more compounds from the group of compounds consisting of La.sub.2O.sub.3, Al.sub.2O.sub.3, B.sub.2O.sub.3, and Ni; the La.sub.2O.sub.3 less than about 20 mole percent; the Al.sub.2O.sub.3 less than about 25 mole percent; the B.sub.2O.sub.3 less than about 15 mole percent; and the Ni less than about 5 mole percent. Preferably, the glass is substantially free of barium oxide, calcium oxide, magnesia, and alkali oxide. Preferably, the glass is used as a seal in a solid oxide fuel/electrolyzer cell (SOFC) stack. The SOFC stack comprises a plurality of SOFCs connected by one or more interconnect and manifold materials and sealed by the glass. Preferably, each SOFC comprises an anode, a cathode, and a solid electrolyte.

  20. Removal of uranyl ions from aqueous solutions using barium titanate

    International Nuclear Information System (INIS)

    Remediation of water sources contaminated with radioactive waste products is a major environmental issue that demands new and more efficient technologies. For this purpose, we report a highly efficient ion-exchange material for the removal of radioactive nuclides from aqueous solutions. The kinetic characteristics of adsorption of uranyl ions on the surface of barium titanate were investigated using a spectrophotometric method under a wide range of conditions. By controlling the pH it was possible to exert fine control over the speciation of uranium, and by optimizing the temperature and grain size of the exchanger, almost total removal was achieved in a matter of just hours. The highest efficiency (>90 % removal) was realized at high temperature (80 deg C). Moreover, the effect of competitive ion adsorption from a range of different cations and anions was quantified. Adsorption was found to follow first-order kinetics and both Freundlich and Langmuir isotherms could be applied to this system. The results of a mathematical treatment of the kinetic data combined with the observation that adsorption was independent of stirring speed and dependent on the ion-exchanger grain size, indicate that the dominant mechanism influencing adsorption is particle spreading. The adsorption behavior was not influenced by exposure to high-intensity gamma radiation, indicating potential for use of this ion-exchanger in systems containing radioactive material. These results will be of use in the development of uranium extraction systems for contaminated water sources. (author)

  1. Colonic diverticulosis: evaluation with double contrast barium enema

    International Nuclear Information System (INIS)

    To evaluate the pattern of colonic diverticulosis according to age and sex, and recent trend. The authors retrospectively reviewed 120 cases of colonic diverticulosis in 1,020 patients who had undergone a double contrast barium enema examination between January 1st, 1993, and December 31st, 1995, and analyzed the frequency, size, multiplicity and anatomical site, according to age and sex. Diverticulum size was classified into one of three groups : less than 5mm, 5-10mm, over 10mm in diameter. The overall incidence of colonic diverticulosis was 120 cases among 1,020 patients(11.8%) with an incidence 5.3 times higher in males than in females. Peak incidence was in the fifth decade, with 19 cases (15.8%) among males, and after the sixth decade, with four cases(3.3%) among females. Mean age was 57.7 years. Diverticulum size of 5-10mm in diameter was predominant (2% of cases); average diameter was 5-6mm. The incidence of colonic diverticulosis was 5.1 times more frequent in the right colon (101 cases) than in the left (20 cases). The overall incidence of colonic diverticulosis has continually increased; in addition it has also recently increased slightly in left-sided colon. This is thought to be due to various factors, both congenital and acquired, including longer life with good health care, constipation, irritable bowel syndrome, stress and the tendency of eating patterns to more closely resemble those of the west

  2. Abundance analysis of s-process enhanced barium stars

    Science.gov (United States)

    Mahanta, Upakul; Karinkuzhi, Drisya; Goswami, Aruna; Duorah, Kalpana

    2016-08-01

    Detailed chemical composition studies of stars with enhanced abundances of neutron-capture elements can provide observational constraints for neutron-capture nucleosynthesis studies and clues for understanding their contribution to the Galactic chemical enrichment. We present abundance results from high-resolution spectral analyses of a sample of four chemically peculiar stars characterized by s-process enhancement. High-Resolution spectra (R ˜42000) of these objects spanning a wavelength range from 4000 to 6800 Å, are taken from the ELODIE archive. We have estimated the stellar atmospheric parameters, the effective temperature Teff, the surface gravity log g, and metallicity [Fe/H] from local thermodynamic equilibrium analysis using model atmospheres. We report estimates of elemental abundances for several neutron-capture elements, Sr, Y, Zr, Ba, La, Ce, Pr, Nd, Sm, Eu and Dy. While HD 49641 and HD 58368 show [Ba/Fe] ≥ 1.16 the other two objects HD 119650 and HD 191010 are found to be mild barium stars with [Ba/Fe] ˜ 0.4. The derived abundances of the elements are interpreted on the basis of existing theories for understanding their origin and evolution.

  3. Structural and magnetic properties of barium-gadolinium hexaferrites

    Energy Technology Data Exchange (ETDEWEB)

    Litsardakis, G. [Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece)]. E-mail: Lits@eng.auth.gr; Manolakis, I. [Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Serletis, C. [Department of Physics, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Efthimiadis, K.G. [Department of Physics, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece)

    2007-03-15

    A series of Gd-substituted M-type barium hexaferrites has been prepared by the ceramic route, according to the formula (Ba{sub 1-x}Gd{sub x})O.5.25Fe{sub 2}O{sub 3} (x=0-0.30). XRD analysis revealed that all the samples present primarily an M-type structure. Samples x=0 and x=0.05 are single-phase. Hematite (Fe{sub 2}O{sub 3}) and GdFeO{sub 3} were detected in the remaining samples. Coercivity (H{sub c}) shows remarkably high values, {approx}293kA/m for x=0.20 and 0.30 with a maximum of 322kA/m for x=0.25. Specific saturation magnetization ({sigma}{sub sat}) of the samples presents a small increase up to x=0.10. The microstructure examination indicates that Gd may act as a grain growth inhibitor.

  4. Nanoscale inhomogeneities in yttrium-barium-copper-oxide (YBCO) superconductors

    Science.gov (United States)

    Islam, Zahirul; Sinha, S. K.; Lang, J. C.; Liu, X.; Haskel, D.; Moss, S. C.; Srajer, G.; Veal, B. W.; Wermeille, D.; Lee, D. R.; Haeffner, D. R.; Welp, U.; Wochner, P.

    2004-03-01

    X-ray diffraction studies at the Advanced Photon Source reveal that nanoscale inhomogeneities, electronic or structural in origin, form in yttrium-barium-copper-oxide (YBa_2Cu_3O_6+x) superconductors and coexist with the superconducting (SC) state. Diffuse scattering from these inhomogeneous superstructures is due to atomic displacements with respect to equilibrium lattice sites (Z. Islam et al. Phys. Rev. B 66, 92501 (2002)), that are characterized by a wavevector of the form q=(q_x,0,0), where qx varies with hole doping from 2 unit cells (along shorter Cu-O-Cu direction) for very low doping to 4 unit cells at optimal doping. Interestingly, while these superstructures are 3-dimensionally ordered when the SC state is weakened (e.g., at x=0.4), as the doping increases, they become quasi 1D with correlation lengths comparable to SC coherence lengths in these cuprates. Recent first-principles calculations (D. de Fontaine et al., to be published) for the x=0.63 compound show that atomic displacements consistent with experimental data can be the result of ordering of O vacancies in YBCO. Models for various superstructures and their role in the phase diagram will be discussed.

  5. Properties of barium strontium titanate at millimeter wave frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Osman, Nurul [Department of Physics, Universiti Putra Malaysia (Malaysia); Free, Charles [Department of Engineering and Design, University of Sussex (United Kingdom)

    2015-04-24

    The trend towards using higher millimetre-wave frequencies for communication systems has created a need for accurate characterization of materials to be used at these frequencies. Barium Strontium Titanate (BST) is a ferroelectric material whose permittivity is known to change as a function of applied electric field and have found varieties of application in electronic and communication field. In this work, new data on the properties of BST characterize using the free space technique at frequencies between 145 GHz and 155 GHz for both thick film and bulk samples are presented. The measurement data provided useful information on effective permittivity and loss tangent for all the BST samples. Data on the material transmission, reflection properties as well as loss will also be presented. The outcome of the work shows through practical measurement, that BST has a high permittivity with moderate losses and the results also shows that BST has suitable properties to be used as RAM for high frequency application.

  6. Properties of barium strontium titanate at millimeter wave frequencies

    International Nuclear Information System (INIS)

    The trend towards using higher millimetre-wave frequencies for communication systems has created a need for accurate characterization of materials to be used at these frequencies. Barium Strontium Titanate (BST) is a ferroelectric material whose permittivity is known to change as a function of applied electric field and have found varieties of application in electronic and communication field. In this work, new data on the properties of BST characterize using the free space technique at frequencies between 145 GHz and 155 GHz for both thick film and bulk samples are presented. The measurement data provided useful information on effective permittivity and loss tangent for all the BST samples. Data on the material transmission, reflection properties as well as loss will also be presented. The outcome of the work shows through practical measurement, that BST has a high permittivity with moderate losses and the results also shows that BST has suitable properties to be used as RAM for high frequency application

  7. Combustion synthesis, characterization and luminescence properties of barium aluminate phosphor

    Institute of Scientific and Technical Information of China (English)

    AH Wako; FB Dejene; HC Swart

    2014-01-01

    The blue-green emitting Eu2+and Nd3+ doped polycrystalline barium aluminate (BaAl2O4:Eu2+,Nd3+) phosphor, was pre-pared by a solution-combustion method at 500 ºC without a post-annealing process. The characteristic variation in the structural and luminescence properties of the as-prepared samples was evaluated with regards to a change in the Ba/Al molar ratio from 0.1:1 to 1.4:1. The morphologies and the phase structures of the products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), while the optical properties were investigated using ultra-violet (UV) and photoluminescence (PL) spectroscopy, respectively. The XRD and TEM results revealed that the average crystallite size of the BaAl2O4:Eu2+,Nd3+ phosphor was about 70 nm. The broad-band UV-excited luminescence of the phosphors was observed atλmax=500 nm due to transitions from the 4f65d1 to the 4f7 configuration of the Eu2+ ion. The PL results indi-cated that the main peaks in the emission and excitation spectrum of phosphor particles slightly shifted to the short wavelength due to the changes in the crystal field due to the structure changes caused by the variation in the quantity of the Ba ions in the host lattice.

  8. Colonic diverticulosis: evaluation with double contrast barium enema

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Jae Kook; Lee, Jong Koo; Yun, Eun Joo; Moon, Hee Jung; Shin, Hyun Ja [Korea Veterans Hospital, Seoul (Korea, Republic of)

    1997-02-01

    To evaluate the pattern of colonic diverticulosis according to age and sex, and recent trend. The authors retrospectively reviewed 120 cases of colonic diverticulosis in 1,020 patients who had undergone a double contrast barium enema examination between January 1st, 1993, and December 31st, 1995, and analyzed the frequency, size, multiplicity and anatomical site, according to age and sex. Diverticulum size was classified into one of three groups : less than 5mm, 5-10mm, over 10mm in diameter. The overall incidence of colonic diverticulosis was 120 cases among 1,020 patients(11.8%) with an incidence 5.3 times higher in males than in females. Peak incidence was in the fifth decade, with 19 cases (15.8%) among males, and after the sixth decade, with four cases(3.3%) among females. Mean age was 57.7 years. Diverticulum size of 5-10mm in diameter was predominant (2% of cases); average diameter was 5-6mm. The incidence of colonic diverticulosis was 5.1 times more frequent in the right colon (101 cases) than in the left (20 cases). The overall incidence of colonic diverticulosis has continually increased; in addition it has also recently increased slightly in left-sided colon. This is thought to be due to various factors, both congenital and acquired, including longer life with good health care, constipation, irritable bowel syndrome, stress and the tendency of eating patterns to more closely resemble those of the west.

  9. Barium in landscape components of the western Transbaikal region

    Science.gov (United States)

    Kashin, V. K.

    2015-10-01

    Barium concentrations in parent materials, soils, and plants of the forest-steppe, steppe, and dry steppe landscapes of the Transbaikal region have been studied. The average concentration of this element in rocks and soils of this region exceeds its clarke by 1.8-2.1 times. A positive correlation between the contents of Ba in soils, soil-forming rocks, and plants has been found. The concentration of Ba in soils does not correlate with the soil pH and humus content. Distribution patterns of Ba in the soil profiles have been characterized. With respect to the coefficient of the biological uptake by plants, Ba is assigned to the group of low accumulation (0.55-0.65) for mineral soils and of strong accumulation (6.0) for alluvial bog soils. Average concentrations of Ba in the steppe, meadow, and cultivated vegetation of the region are 1.9-2.3 times higher in comparison with the average concentration of this element in plants of the continents. The biological migration of Ba is most active in meadow landscapes, whereas steppe landscapes are characterized by the least active biological migration of this element.

  10. Abundance analysis of s-process enhanced barium stars

    CERN Document Server

    Mahanta, Upakul; Goswami, Aruna; Duorah, Kalpana

    2016-01-01

    Detailed chemical composition studies of stars with enhanced abundances of neutron-capture elements can provide observational constraints for neutron-capture nucleosynthesis studies and clues for understanding their contribution to the Galactic chemical enrichment. We present abundance results from high-resolution spectral analyses of a sample of four chemically peculiar stars characterized by s-process enhancement. High-Resolution spectra (R ~ 42000) of these objects spanning a wavelength range from 4000 to 6800 A, are taken from the ELODIE archive. We have estimated the stellar atmospheric parameters, the effective temperature T_eff, the surface gravity log g, and metallicity [Fe/H] from local thermodynamic equilibrium analysis using model atmospheres. We report estimates of elemental abundances for several neutron-capture elements, Sr, Y, Zr, Ba, La, Ce, Pr, Nd, Sm, Eu and Dy. While HD 49641 and HD 58368 show [Ba/Fe] > 1.16 the other two objects HD 119650 and HD 191010 are found to be mild barium stars wit...

  11. Gastrointestinal tract labeling for MDCT of abdomen: Comparison of low density barium and low density barium in combination with water

    Energy Technology Data Exchange (ETDEWEB)

    Gulati, Kavita; Shah, Zarine K.; Sainani, Nisha; Uppot, Raul; Sahani, Dushyant V. [Massachusetts General Hospital and Harvard Medical School, Department of Abdominal Imaging and Intervention, Boston, MA (United States)

    2008-05-15

    The purpose of the study was to compare the quality of stomach and small bowel marking/labeling using 1,350 ml of low-density barium alone (Volumen) with 900 ml of low-density barium and 450 ml of water for 16-MDCT scans of the abdomen and pelvis and assess cost benefits with the two protocols. In this IRB approved study, 80 consecutive patients scheduled for routine CECT (contrast-enhanced CT) of the abdomen-pelvis were studied. Patients were randomized into two groups and were administered either 1,350 ml of VoLumen (two bottles at 20-min intervals, one half bottle at 50 min and the last half on the table) or 900 ml of Volumen (two bottles at 20-min intervals and 450 ml water on the table). Portal venous phase scanning (detector collimation = 0.625 mm, speed = 18.75 mm, thickness = 5 mm) was subsequently performed. Images were reconstructed in axial and coronal plane at the CT console. Two blinded readers used a pre-designed template to assess distension and wall characteristics of the stomach and small bowel on a 5-point scale. Median scores with the two protocols were compared using the Wilcoxon rank sum test. The stomach and small bowel labeling was rated fair to optimal in all patients and did not differ significantly in the two protocols. The mean scores for distension of the small bowel and stomach were comparable. Inter-observer agreement for bowel labeling was found to be excellent (k 0.81). With the use of coronal images there was increased reader confidence in tracing the small bowel with both protocols. Acceptance for two bottles of Volumen and water was greater among patients as compared to three bottles of VoLumen. Use of two bottles of Volumen and water combination cost less than three bottles of Volumen. Stomach and small bowel labeling with administration of 900 ml of Volumen followed by 450 ml of water is cost effective and compares well to 1,350 ml of Volumen alone. (orig.)

  12. 49 CFR 229.137 - Sanitation, general requirements.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Sanitation, general requirements. 229.137 Section... Cab Equipment § 229.137 Sanitation, general requirements. (a) Sanitation compartment. Except as provided in paragraph (b) of this section, all lead locomotives in use shall be equipped with a...

  13. 36 CFR 223.137 - Causes for debarment.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Causes for debarment. 223.137... DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER Suspension and Debarment of Timber Purchasers § 223.137 Causes for debarment. The debarring official may debar a purchaser for any of the following causes:...

  14. Accumulation and distribution 137Сs in predators’ organism

    Directory of Open Access Journals (Sweden)

    A. V. Gulakov

    2007-10-01

    Full Text Available Data of the long-term research of accumulation and distribution 137Cs radionuclide in organisms of predatory wild animals from the alienation zone of the Chernobyl nuclear power station are presented. Essential fluctuations of the 137Cs contents in muscular tissue are noted. The results have large practical value for management of the hunting facilities on the radioactively polluted territories.

  15. 14 CFR 137.39 - Economic poison dispensing.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Economic poison dispensing. 137.39 Section... AIRCRAFT OPERATIONS Operating Rules § 137.39 Economic poison dispensing. (a) Except as provided in... economic poison that is registered with the U.S. Department of Agriculture under the Federal...

  16. 49 CFR 37.137 - Paratransit plan development.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Paratransit plan development. 37.137 Section 37... WITH DISABILITIES (ADA) Paratransit as a Complement to Fixed Route Service § 37.137 Paratransit plan... the plan to identify any person or entity (public or private) which provides a paratransit or...

  17. 40 CFR 49.137 - Rule for air pollution episodes.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Rule for air pollution episodes. 49.137... Application to Indian Reservations in Epa Region 10 § 49.137 Rule for air pollution episodes. (a) What is the... of an air pollution emergency within the Indian reservation due to the effects of these...

  18. 10 CFR 26.137 - Quality assurance and quality control.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Quality assurance and quality control. 26.137 Section 26....137 Quality assurance and quality control. (a) Quality assurance program. Each licensee testing facility shall have a quality assurance program that encompasses all aspects of the testing...

  19. Cumulative deposition of 137Cs in the soil of Korea

    International Nuclear Information System (INIS)

    The cumulative deposition of 137Cs in the soil of Korea has been studied. Using γ-ray spectrometry, the concentrations of 137Cs were determined for the soil samples collected to a depth of 20 cm. The average accumulated depositions of 137Cs were estimated roughly to be 2,501 ±499 Bq m-2 in the forest and 1,058 ±322 Bq m-2 in the hill. The inventory value of 137Cs in the forest is about two times higher than that in the hill. Except for some cases, the concentrations of 137Cs in the undisturbed soils decreased exponentially with increasing the soil depth. The influences of rainfall, organic matter content, clay content and pH on the deposition of 137Cs were studied using the field method. Among these factors, the organic matter content played the most important role in the retention and relative mobility of 137Cs in the soil. The other factors such as rainfall, clay content and pH showed weak correlation with the deposition of 137Cs in the soil

  20. 21 CFR 146.137 - Frozen orange juice.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen orange juice. 146.137 Section 146.137 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CANNED FRUIT JUICES Requirements for Specific Standardized Canned Fruit Juices...

  1. Identification of 137Cs Reference Sites in Southeastern China

    Institute of Scientific and Technical Information of China (English)

    TANG Xiang-Yu; YANG Hao; DU Ming-Yuan; ZHAO Qi-Guo; LI Ren-Ying

    2006-01-01

    The 137Cs vertical distributions in uncultivated and cultivated soils, developed from Quaternary red clay, granite,argillaceous shale, and red sandstone, were studied to develop reliable guidelines for selecting reference sites in southeastern China, which is dominated by strong acidic and/or clay-textured soils, and examine their reliability by comparing them to the reported 137Cs reference inventory data to see whether they agreed with the global distribution pattern. It was observed that a relatively high proportion of 137Cs was concentrated in the surface layers of soils with relatively high clay content. In the paddy soils developed from granite more 137Cs penetrated to depths below the plow layer (about 45.3%),when compared to those from the other three parent materials. The relatively low soil 137Cs inventories on crests excluded using the crest as the 137Cs reference site; instead the paddy field on the hillock plain was selected. Furthermore, within a specific county characterized by great systematic spatial variations of rainfall and topography across the landscape,a significant (P < 0.01) and positive linear relationship (r2 = 0.81) between local 137Cs inventory and corresponding local annual rainfall was observed. Thus, for areas with large variations in rainfall, a single uniform value of local 137Cs reference inventory should be used with caution.

  2. 29 CFR 1910.137 - Electrical protective equipment.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Electrical protective equipment. 1910.137 Section 1910.137... Electrical protective equipment. (a) Design requirements. Insulating blankets, matting, covers, line hose... portion of the glove. (2) Electrical requirements. (i) Equipment shall be capable of withstanding the...

  3. 14 CFR 137.51 - Operation over congested areas: General.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Operation over congested areas: General. 137.51 Section 137.51 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS AND OPERATORS FOR COMPENSATION OR HIRE: CERTIFICATION AND OPERATIONS AGRICULTURAL AIRCRAFT OPERATIONS Operating Rules...

  4. 21 CFR 133.137 - Washed curd cheese for manufacturing.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Washed curd cheese for manufacturing. 133.137... Standardized Cheese and Related Products § 133.137 Washed curd cheese for manufacturing. Washed curd cheese for manufacturing conforms to the definition and standard of identity prescribed for washed curd cheese by §...

  5. 14 CFR 21.137 - Location of manufacturing facilities.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Location of manufacturing facilities. 21.137 Section 21.137 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... manufacturing facilities. The Administrator does not issue a production certificate if the...

  6. Skylab-barium alpha and beta L = 6 field-line tracing experiments

    International Nuclear Information System (INIS)

    Events SKYLAB-BARIUM ALPHA (27 November 1973) and BETA (4 December 1973) were shaped-charge barium field-line tracing experiments near L approximately equal to 6, conducted jointly by the Los Alamos Scientific Laboratory and the University of Alaska Geophysical Institute. Image-orthicon and pulsed intensified auroral cameras provided data for triangulating the fast ion streaks. Using the POGO 10-68, epoch 1965.0, field-line model with Mead-Fairfield corrections for the outer field, the triangulated positions of the fast ion streak were projected down to the 100 km altitude northern conjugate surface. The projected positions moved toward magnetic east with a velocity of 725 m/sec for both SKYLAB-BARIUM ALPHA and BETA. Assuming only an E x B/B2 force, this drift velocity is consistent with an electric field toward magnetic south of 39 mV/m. Radiometric analysis of the filtered, intensified auroral camera records gave observed peak radiance values of about 2 x 10-11 watts/cm2-Sr in the 455.4 nm line of Ba+. The barium in the portion of the ion streak for which radiometric data were obtained had initial injection velocities of 9.5 to 13.5 km/sec in both events. This portion of the ion streak for both SKYLAB-BARIUM ALPHA and BETA contained approximately 4 x 1023 ions compared to the 6.4 x 1024 atoms contained in the barium liner. Ion inventory estimates are based on a solution of the statistical equilibrium equations. Corrections have been made in the ion inventory calculations for Doppler shifts of the solar spectrum as received in the rest frame of the high-velocity barium ions

  7. Accelerating the transit time of barium sulphate suspensions in small bowel examinations

    International Nuclear Information System (INIS)

    Purpose: To determine whether hyperosmolar and effervescent agents proven individually to accelerate transit time in the barium small bowel examination have an additive effect when combined, surpassing that of either agent alone. Materials and methods: One hundred and forty-nine patients were randomised to four groups. Three hundred milliliters of barium sulphate alone was given to the first group. Fifteen milliliters of iodinated hyperosmolar contrast agent (Gastrografin, meglumine/sodium diatrizoate, Schering) was given in addition to barium sulphate to the second group while six packets of effervescent granules (Carbex, Ferring) were added for the third group. The final group was given a combination of both additives and barium sulphate. The time taken following ingestion for the contrast column to reach the caecum, as assessed by frequent interval fluoroscopy, was recorded. A subgroup of 32 patients were selected randomly from the four groups, 8 from each and assessed for quality of examination. Statistical assessments were made using Kruskal-Wallis and Mann-Whitney tests. Results: One hundred and nineteen patients were analysed after exclusions. The addition of accelerant to barium sulphate, both individually and in combination significantly reduced the small bowel transit time (p < 0.001). No significant difference existed between the additives when used with barium alone. The combined group had significantly faster transit times compared to the hyperosmolar group (p = 0.02). Differences between combined and effervescent groups tended towards significance (p = 0.09). No significant difference existed between groups when examination quality was assessed. Conclusion: These results suggest that the addition of combined effervescent and hyperosmolar agents to the barium suspension may significantly shorten the small bowel transit time without adversely affecting examination quality. This has implications for patient acceptability of the examination as well as

  8. An 8-year review of barium studies in the diagnosis of gastroparesis

    Energy Technology Data Exchange (ETDEWEB)

    Levin, A.A. [Department of Radiology, Hospital of University of Pennsylvania, Philadelphia, PA (United States); Levine, M.S. [Department of Radiology, Hospital of University of Pennsylvania, Philadelphia, PA (United States)], E-mail: marc.levine@uphs.upenn.edu; Rubesin, S.E.; Laufer, I. [Department of Radiology, Hospital of University of Pennsylvania, Philadelphia, PA (United States)

    2008-04-15

    Aim: To determine the utility of barium studies for diagnosing gastroparesis in patients with nausea, vomiting, or other related symptoms. Materials and methods: Radiology files revealed gastroparesis without gastric outlet obstruction on upper gastrointestinal tract barium studies in 50 patients with nausea, vomiting, and other related symptoms. Original reports and images were reviewed to determine whether gastric peristalsis was decreased/absent and to investigate gastric dilatation, fluid or debris, and delayed emptying of barium. Twenty patients (40%) had nuclear gastric emptying studies. Medical records were reviewed to determine the presentation, treatment, and course. The diagnosis of gastroparesis was considered accurate if patients with gastroparesis on barium studies responded to treatment. Results: Forty-six patients (92%) had predisposing factors for gastroparesis, including narcotics and diabetes. Forty-five patients (90%) presented with nausea or vomiting, and 40 patients (80%) had one or more other symptoms, including bloating, early satiety, postprandial fullness, and abdominal pain. Barium studies revealed decreased gastric peristalsis in 46 (92%) of the 50 patients and absent peristalsis in four (8%); 46 patients (92%) had additional findings, including gastric dilatation in 30 (60%), delayed emptying of barium in 27 (54%), debris in 28 (56%; bezoars in three), and retained fluid in 13 (26%). Thirteen (65%) of 20 patients with nuclear gastric emptying studies had delayed emptying of solids and seven (35%) had normal emptying. Thirty-five (83%) of 42 patients treated for gastroparesis had symptomatic improvement versus two (25%) of eight patients not treated. Conclusion: Patients with nausea, vomiting, or other related symptoms who have gastroparesis without gastric outlet obstruction on barium studies can be treated for this condition on the basis of the clinical and radiographic findings.

  9. Preparation and properties of yttria doped tetragonal zirconia polycrystal/Sr-doped barium hexaferrite ceramic composites

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shanshan; Zhang, Chao; Guo, Ruisong, E-mail: rsguo@tju.edu.cn; Liu, Lan; Yang, Yuexia; Li, Kehang

    2015-03-15

    Highlights: • The 3Y-TZP/Sr-doped barium ferrite composites were prepared. • The saturation magnetization was improved by 15% with Sr-doping. • The dispersion coefficient p could reflect the microscopic lattice variation. • The composite with x = 0.5 had the maximum fracture toughness of 8.3 MPa m{sup 1/2}. - Abstract: The effects of substitution of Ba{sup 2+} by Sr{sup 2+} on the magnetic property of barium ferrite and addition barium ferrite secondary phase to the 3 mol% yttria-doped tetragonal zirconia polycrystal (3Y-TZP) matrix on the mechanical property of composites were investigated. The Sr-doped barium ferrite (Ba{sub 1−x}Sr{sub x}Fe{sub 12}O{sub 19}, x = 0, 0.25, 0.50 and 0.75) was synthesized by solid-state reaction in advance. Then 3Y-TZP/20 wt% Sr-doped barium ferrite composites were prepared by means of conventional ceramic method. It was found that a moderate amount of Sr added to barium ferrite could boost the saturation magnetization by 15% compared with the composites without Sr-doping. Besides, the composite with x = 0.50 possessed the best mechanical properties, such as 11.5 GPa for Vickers hardness and 8.3 MPa m{sup 1/2} for fracture toughness, respectively. It was demonstrated that magnetic and mechanical properties of the composites could be harmonized by the incorporation of barium ferrite secondary phase.

  10. Obtaining of a barium compound by combustion chemistry and their evaluation as Co adsorbent

    International Nuclear Information System (INIS)

    In this work, barium carbonate synthesized by chemical combustion method using a chemical precursor prepared by the combination of barium nitrate and urea as a fuel, with a 1:1 molar ratio in aqueous solution, the chemical precursor was heated to evaporate excess water, producing a homogeneous viscous liquid, that when heated to 900 centi grades for 5 minutes an exothermic reaction was produced very quickly and abruptly, forming a white powder final product, fine porous, little spongy, dry and crystalline ready to be used as material adsorbent. Additionally, the effect of water on the synthesis by chemical combustion was studied. Simultaneously, and with the purpose of comparing the advantages and disadvantages of the method by chemical combustion, barium carbonate was synthesized by precipitation method using barium nitrate salts and sodium carbonate. Synthesized barium carbonate, was characterized by X-ray diffraction, thermal gravimetric analysis, infrared spectrometry and scanning electron microscopy. We studied the adsorption capacity of Co present in aqueous solution by static tests on materials synthesized at room temperature using the neutron activation analysis. It was found that the synthesis by chemical combustion provides an interesting alternative compared to the synthesis by precipitation because it offers simplicity of synthesis and speed to have a good adsorbent material. It was found that the barium carbonate synthesized by the chemical combustion method using in their synthesis 1.0 ml of water, was the one who achieved the maximum adsorption capacity of 95.6% compared with the barium carbonate prepared by precipitation, which reached a capacity adsorption of 51.48%. (Author)

  11. 氯化钡除杂制取高纯氢氧化钡%Preparation of high purity barium hydroxide by impurity - removed barium chloride

    Institute of Scientific and Technical Information of China (English)

    翁贤芬; 毛逢银; 何琳; 李莉

    2009-01-01

    Removal technology of strontium and iron from crude barium chloride raw material were studied.Optimization of process conditions of strontium and iron removal were discussed.When crude barium chloride stiring and dissolving the mixture at 60 ℃ for 40 min,impurities of stromtium and calcuim can be removed and mass fraction of strontium in the obatined solid barium chloride was below 1×10-4.Then add oxydol (H2O2) at proportion of 100 g raw materials per 8 mL H2O2,and add active carbon and small quantity of sodium hydroxide.Finally,iron could be get rid of when pH was controlled below 10.Mass fraction of iron in barium hydroxide product was less than 1×10-5 when using the iron - removed barium chaloride as raw material.Therefore,purified barium chloride by this method can be used to produce purity barium hydroxide.%研究了粗氯化钡原料中锶和铁杂质的脱除工艺,探讨了脱除锶和铁的优化工艺条件.在粗氯化钡原料中加入去离子水,液固质量比为0.25: 1,在60 ℃下搅拌溶解40 min,可除去锶和钙杂质,所得氯化钡固体中锶质量分数低于1×10-4.在氯化钡溶液中加入双氧水,每100 g原料中加入双氧水8 mL,加入活性炭和少量氢氧化钠,控制pH低于10时,可除去铁杂质,用除铁后的氯化钡制取氢氧化钡,产品中铁质量分数低于1×10-5.用除杂后的氯化钡可制得高纯氢氧化钡.

  12. Sediment environmental capacity of 137Cs in Daya Bay

    Institute of Scientific and Technical Information of China (English)

    ZHANG Junli; CHEN Jiajun; XU Jialin; LI Yuanxin; HUANG Naiming

    2007-01-01

    Sediment environmental capacity of pollutants is very important for marine environmental management.Based on the methodology of a study on water,soil environmental capacity,and mass conservation theory in a system,the concept and model on sediment environmental capacity for 137Cs in Daya Bay were developed.The static capacity for 137Cs in the upper sediment near the shore at a shallow area was calculated,and the annual dynamic capacity and total dynamic capacity were also calculated through determination of the typical biomass in the sediment.The results showed that the estimated environmental capacity for 137Cs in sediments was approximately equal to the current input of 137Cs into the sediments.Controlling the input of 137Cs in the sediments within the environmental capacity guarantees the sustainability of the current situation of the Daya Bay ecosystem and avoidance of a significant degradation of the system.

  13. Spectroscopic (multi-energy) CT distinguishes iodine and barium contrast material in MICE

    International Nuclear Information System (INIS)

    Spectral CT differs from dual-energy CT by using a conventional X-ray tube and a photon-counting detector. We wished to produce 3D spectroscopic images of mice that distinguished calcium, iodine and barium. We developed a desktop spectral CT, dubbed MARS, based around the Medipix2 photon-counting energy-discriminating detector. The single conventional X-ray tube operated at constant voltage (75 kVp) and constant current (150 μA). We anaesthetised with ketamine six black mice (C57BL/6). We introduced iodinated contrast material and barium sulphate into the vascular system, alimentary tract and respiratory tract as we euthanised them. The mice were preserved in resin and imaged at four detector energy levels from 12 keV to 42 keV to include the K-edges of iodine (33.0 keV) and barium (37.4 keV). Principal component analysis was applied to reconstructed images to identify components with independent energy response, then displayed in 2D and 3D. Iodinated and barium contrast material was spectrally distinct from soft tissue and bone in all six mice. Calcium, iodine and barium were displayed as separate channels on 3D colour images at <55 μm isotropic voxels. Spectral CT distinguishes contrast agents with K-edges only 4 keV apart. Multi-contrast imaging and molecular CT are potential future applications. (orig.)

  14. SALT reveals the barium central star of the planetary nebula Hen 2-39

    CERN Document Server

    Miszalski, B; Jones, D; Karakas, A I; Köppen, J; Tyndall, A A; Mohamed, S S; Rodríguez-Gil, P; Santander-García, M

    2013-01-01

    Classical barium stars are binary systems which consist of a late-type giant enriched in carbon and slow neutron capture (s-process) elements and an evolved white dwarf (WD) that is invisible at optical wavelengths. The youngest observed barium stars are surrounded by planetary nebulae (PNe), ejected soon after the wind accretion of polluted material when the WD was in its preceeding asymptotic giant branch (AGB) phase. Such systems are rare but powerful laboratories for studying AGB nucleosynthesis as we can measure the chemical abundances of both the polluted star and the nebula ejected by the polluter. Here we present evidence for a barium star in the PN Hen 2-39. The polluted giant is very similar to that found in WeBo 1. It is a cool (Teff=4250 +/- 150 K) giant enhanced in carbon ([C/H]=0.42 +/- 0.02 dex) and barium ([Ba/Fe]=1.50 +/- 0.25 dex). A spectral type of C-R3 C_24 nominally places Hen 2-39 amongst the peculiar early R-type carbon stars, however the barium enhancement and likely binary status mea...

  15. Determination of barium in surface and ground waters at Centro Experimental Aramar area

    Energy Technology Data Exchange (ETDEWEB)

    Matoso, Erika, E-mail: ematoso@hotmail.com [Centro Tecnologico da Marinha em Sao Paulo (CEA/CTMS), Ipero, SP (Brazil). Centro Experimental Aramar; Cadore, Solange, E-mail: cadore@iqm.unicamp.br [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Instituto de Quimica. Departamento de Quimica Analica

    2015-07-01

    Barium can be found in waters up to 1 mg L{sup -1} and came from natural sources such as sedimentary rocks erosion rich in feldspar and barite. Also anthropogenic activities can release this element such as oil and gas industry, agricultural defensives, chemical industry and waste disposal. At high doses, barium can be harmful to human central nervous system and can also cause high blood pressure, heart problems, fatigue and anxiety. The water potability defined by Brazilian's Ministry of Healthy sets barium concentration up to 0.7 mg L{sup -1} and official regulation defines the same limit of this element to superficial waters (according CONAMA resolution 357/2005) and ground waters (Sao Paulo state regulation). In this work, barium was analyzed monthly in superficial waters from 4 different sampling locations, located in a ratio of 10-km-long from Centro Experimental Aramar (CEA) at Ipanema River, during one year, in order to evaluate the river in different conditions (seasons, temperature and rain period). The ground water was collected every six months. The analytical technique applied was ICP OES and the method conditions were optimized: wavelength, linearity, signal background ratio, detection and quantification limits. Data obtained in this work will contribute to evaluate the presence of barium at CEA region and nearby in order to compare it with current Brazilian regulations. (author)

  16. Spectroscopic (multi-energy) CT distinguishes iodine and barium contrast material in MICE

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, N.G. [University of Otago, Department of Radiology, Christchurch (New Zealand); Butler, A.P. [University of Otago, Department of Radiology, Christchurch (New Zealand); University of Canterbury, Physics and Astronomy, Christchurch (New Zealand); Scott, N.J.A. [University of Otago, Department of Medicine, Christchurch (New Zealand); Cook, N.J. [Christchurch Hospital, Medical Physics and Bioengineering, Christchurch (New Zealand); Butzer, J.S. [Karlsruhe Institute of Technology, Physics Department, Karlsruhe (Germany); Schleich, N. [University of Canterbury, Physics and Astronomy, Christchurch (New Zealand); Christchurch Hospital, Medical Physics and Bioengineering, Christchurch (New Zealand); Firsching, M. [Friedrich Alexander University, Physics Department, Erlangen (Germany); Grasset, R.; Ruiter, N. de [University of Canterbury, Hitlab NZ, Christchurch (New Zealand); Campbell, M. [European Organisation for Nuclear Research, Physics Section, Geneva (Switzerland); Butler, P.H. [University of Canterbury, Physics and Astronomy, Christchurch (New Zealand)

    2010-09-15

    Spectral CT differs from dual-energy CT by using a conventional X-ray tube and a photon-counting detector. We wished to produce 3D spectroscopic images of mice that distinguished calcium, iodine and barium. We developed a desktop spectral CT, dubbed MARS, based around the Medipix2 photon-counting energy-discriminating detector. The single conventional X-ray tube operated at constant voltage (75 kVp) and constant current (150 {mu}A). We anaesthetised with ketamine six black mice (C57BL/6). We introduced iodinated contrast material and barium sulphate into the vascular system, alimentary tract and respiratory tract as we euthanised them. The mice were preserved in resin and imaged at four detector energy levels from 12 keV to 42 keV to include the K-edges of iodine (33.0 keV) and barium (37.4 keV). Principal component analysis was applied to reconstructed images to identify components with independent energy response, then displayed in 2D and 3D. Iodinated and barium contrast material was spectrally distinct from soft tissue and bone in all six mice. Calcium, iodine and barium were displayed as separate channels on 3D colour images at <55 {mu}m isotropic voxels. Spectral CT distinguishes contrast agents with K-edges only 4 keV apart. Multi-contrast imaging and molecular CT are potential future applications. (orig.)

  17. High pressure–low temperature phase diagram of barium: Simplicity versus complexity

    Energy Technology Data Exchange (ETDEWEB)

    Desgreniers, Serge [Laboratoire de Physique des Solides Denses, Université d' Ottawa, Ottawa, Ontario K1N 6N5 (Canada); Tse, John S., E-mail: John.Tse@usask.ca [Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B2 (Canada); State Key Laboratory of Superhard Materials, Jilin University, 130012 Changchun (China); Matsuoka, Takahiro [SPring-8/JASRI, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Department of Electrical, Electronic and Computer Engineering, Gifu University, 1-1 Yanagido, Gifu 501-1193 (Japan); Ohishi, Yasuo [SPring-8/JASRI, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Li, Quan; Ma, Yanming [State Key Laboratory of Superhard Materials, Jilin University, 130012 Changchun (China)

    2015-11-30

    Barium holds a distinctive position among all elements studied upon densification. Indeed, it was the first example shown to violate the long-standing notion that high compression of simple metals should preserve or yield close-packed structures. From modest pressure conditions at room temperature, barium transforms at higher pressures from its simple structures to the extraordinarily complex atomic arrangements of the incommensurate and self-hosting Ba-IV phases. By a detailed mapping of the pressure/temperature structures of barium, we demonstrate the existence of another crystalline arrangement of barium, Ba-VI, at low temperature and high pressure. The simple structure of Ba-VI is unlike that of complex Ba-IV, the phase encountered in a similar pressure range at room temperature. First-principles calculations predict Ba-VI to be stable at high pressure and superconductive. The results illustrate the complexity of the low temperature-high pressure phase diagram of barium and the significant effect of temperature on structural phase transformations.

  18. Radiological protection and routinary controls of an activimeter with a cesium and barium sources in an nuclear medicine center; Proteccion radiologica y controles rutinarios de un activimetro con fuentes de cesio y bario en un centro de medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Morales L, M.E. [IPEN INEN, Centro de Medicina Nuclear, Av. Aviacion 3799, Lima 34 (Peru)]. e-mail: toyoco3000@hotmail.com

    2006-07-01

    In the present work the results when carrying out the routine controls in a Deluxe Isotope (Calibrator II) equipment, with some sources of Cesium 137 and Barium 133, in a Nuclear Medicine Center that operates from the year 1983 in a modern one construction inside the Institute of Neoplastic Illnesses (INEN) are shown. Taking in account the Radiological Protection measures to verify if the equipment responds to the personnel's demands in the measurements of activities of the diverse radionuclides that are used in different types of exams that are carried out in this Nuclear Medicine Center are the objectives of this work. This Center was equipped initially with donated equipment by the International Atomic Energy Agency (IAEA) with those that it develops assistance, educational works and of research, giving services to patients of the INEN and other public and private medical centers. (Author)

  19. FIRST DIRECT EVIDENCE THAT BARIUM DWARFS HAVE WHITE DWARF COMPANIONS

    International Nuclear Information System (INIS)

    Barium II (Ba) stars are chemically peculiar F-, G-, and K-type objects that show enhanced abundances of s-process elements. Since s-process nucleosynthesis is unlikely to take place in stars prior to the advanced asymptotic giant branch (AGB) stage, the prevailing hypothesis is that each present Ba star was contaminated by an AGB companion which is now a white dwarf (WD). Unless the initial mass ratio of such a binary was fairly close to unity, the receiving star is thus at least as likely to be a dwarf as a giant. So although most known Ba stars appear to be giants, the hypothesis requires that Ba dwarfs be comparably plentiful and moreover that they should all have WD companions. However, despite dedicated searches with the IUE satellite, no WD companions have been directly detected to date among the classical Ba dwarfs, even though some 90% of those stars are spectroscopic binaries, so the contamination hypothesis is therefore presently in some jeopardy. In this paper, we analyze recent deep, near-UV and far-UV Galaxy Evolution Explorer (GALEX) exposures of four of the brightest of the class (HD 2454, 15360, 26367, and 221531), together with archived GALEX data for two newly recognized Ba dwarfs: HD 34654 and HD 114520 (which also prove to be spectroscopic binaries). The GALEX observations of the Ba dwarfs as a group show a significant far-UV excess compared to a control sample of normal F-type dwarfs. We suggest that this ensemble far-UV excess constitutes the first direct evidence that Ba dwarfs have WD companions.

  20. Radiation doses to children during modified barium swallow studies

    International Nuclear Information System (INIS)

    There are minimal data on radiation doses to infants and children undergoing a modified barium swallow (MBS) study. To document screening times, dose area product (DAP) and effective doses to children undergoing MBS and to determine factors associated with increased screening times and effective dose. Fluoroscopic data (screening time, DAP, kVp) for 90 consecutive MBS studies using pulse fluoroscopy were prospectively recorded; effective dose was calculated and data were analyzed for effects of behavior, number of swallow presentations, swallowing dysfunction and medical problems. Mean effective dose for the entire group was 0.0826 ± 0.0544 mSv, screening time 2.48 ± 0.81 min, and DAP 28.79 ± 41.72 cGy cm2. Significant differences were found across three age groups (≤1.0, >1.0-3.0 and >3.0 years) for effective dose (mean 0.1188, 0.0651 and 0.0529 mSv, respectively; P < 0.001), but not for screening time or DAP. Effective dose was correlated with screening time (P 0.007), DAP (P < 0.001), number of swallow presentations (P = 0.007), lower age (P = 0.017), female gender (P = 0.004), and height (P < 0.001). Screening time was correlated with total number of swallow presentations (P < 0.001) and DAP (P < 0.001). Screening times, DAP, effective dose, and child and procedural factors associated with higher effective doses are presented for children undergoing MBS studies. (orig.)

  1. Radiation doses to children during modified barium swallow studies

    Energy Technology Data Exchange (ETDEWEB)

    Weir, Kelly A. [University of Queensland, Discipline of Paediatrics and Child Health, School of Medicine, Herston, Queensland (Australia); McMahon, Sandra M. [SpeechNet Speech Pathology Services, Brisbane (Australia); Long, Gillian; Bunch, Judith A. [Royal Children' s Hospital, Department of Medical Imaging, Herston (Australia); Pandeya, Nirmala [Queensland Institute of Medical Research, Herston (Australia); Coakley, Kerry S. [Biomedical Technology Services, Royal Brisbane and Women' s Hospital, Herston (Australia); Chang, Anne B. [Royal Children' s Hospital, Department of Respiratory Medicine, Herston (Australia)

    2007-03-15

    There are minimal data on radiation doses to infants and children undergoing a modified barium swallow (MBS) study. To document screening times, dose area product (DAP) and effective doses to children undergoing MBS and to determine factors associated with increased screening times and effective dose. Fluoroscopic data (screening time, DAP, kVp) for 90 consecutive MBS studies using pulse fluoroscopy were prospectively recorded; effective dose was calculated and data were analyzed for effects of behavior, number of swallow presentations, swallowing dysfunction and medical problems. Mean effective dose for the entire group was 0.0826 {+-} 0.0544 mSv, screening time 2.48 {+-} 0.81 min, and DAP 28.79 {+-} 41.72 cGy cm{sup 2}. Significant differences were found across three age groups ({<=}1.0, >1.0-3.0 and >3.0 years) for effective dose (mean 0.1188, 0.0651 and 0.0529 mSv, respectively; P < 0.001), but not for screening time or DAP. Effective dose was correlated with screening time (P = 0.007), DAP (P < 0.001), number of swallow presentations (P = 0.007), lower age (P = 0.017), female gender (P = 0.004), and height (P < 0.001). Screening time was correlated with total number of swallow presentations (P < 0.001) and DAP (P < 0.001). Screening times, DAP, effective dose, and child and procedural factors associated with higher effective doses are presented for children undergoing MBS studies. (orig.)

  2. Distribution of 137Cs in water leachates of forest humus

    International Nuclear Information System (INIS)

    The distribution of 137Cs in water extracts of organic layers of forest soils was investigated using an ultrafiltration method. Samples were taken from two sites in the Bavarian Alps. The different horizons of the organic layers were extracted by column elution with water and 50 mmol/litre CsCl solution. Water extracts were fractionated using membranes with the molecular weight cutoff of 500, 1000 and 3000 Dalton to determine the molecular weight distribution of dissolved organic carbon (DOC). The activity of 137Cs associated with the different DOC-fractions was measured by direct gammaspectrometry. Cesium-137 in the fraction smaller than 500 Dalton was defined as 'ionic'. The results indicated a change of the binding sites depending on the degree of decomposition and humification in the profile. Organic bound 137Cs was identified in all extracts. High mobilities of DOC and 137Cs were observed in the same horizons, fractionation showed then low-molecular-weight DOC and 137Cs mainly in ionic form. In horizons with high-molecular-weight DOC the portion of organic bound 137Cs ranged up to 40%. (author)

  3. Use of the barium enema in the diagnosis of necrotizing enterocolitis

    Energy Technology Data Exchange (ETDEWEB)

    Uken, P.; Smith, W.; Franken, E.A.; Frey, E.; Sato, Y.; Ellerbroek, C.

    1988-01-01

    Necrotizing enterocolitis (NEC) is associated with considerable morbidity and mortality in infants. The diagnosis relies heavily upon radiographic and clinical features. Failure to accurately diagnose NEC is associated with a risk of complications and death, however overdiagnosis also causes both morbidity and mortality as well as excessive medical costs. This report documents the use of barium enema to evaluate suspected clinical or radiographic NEC in 31 premature infants with ambiguous clinical and radiographic signs. The enema was normal in 26 infants and no treatment for NEC was given. Only one of these infants developed signs of NEC subsequent to the examination. Five infants had radiographic evidence of colitis including small ulcerations, spasm, intramural extravasation of barium and mucosal irregularity. Two of the five positive cases are pathologically documented. The barium enema can represent a significant improvement in the specificity of the diagnosis of NEC. Its greatest value is in the exclusion of NEC in ambiguous cases.

  4. Highly aligned arrays of high aspect ratio barium titanate nanowires via hydrothermal synthesis

    International Nuclear Information System (INIS)

    We report on the development of a hydrothermal synthesis procedure that results in the growth of highly aligned arrays of high aspect ratio barium titanate nanowires. Using a multiple step, scalable hydrothermal reaction, a textured titanium dioxide film is deposited on titanium foil upon which highly aligned nanowires are grown via homoepitaxy and converted to barium titanate. Scanning electron microscope images clearly illustrate the effect the textured film has on the degree of orientation of the nanowires. The alignment of nanowires is quantified by calculating the Herman's Orientation Factor, which reveals a 58% improvement in orientation as compared to growth in the absence of the textured film. The ferroelectric properties of barium titanate combined with the development of this scalable growth procedure provide a powerful route towards increasing the efficiency and performance of nanowire-based devices in future real-world applications such as sensing and power harvesting

  5. TiO2 ceramic varistor modified with tantalum and barium

    International Nuclear Information System (INIS)

    The non-linear current (I)-voltage (V) characteristics of titanium dioxide doped with small quantities of tantalum and barium (99.9 TiO2 + 0.1 Ta and 99.4 TiO2 + 0.1 Ta + 0.5 Ba, all are in at.%) were investigated. These samples have the non-linear coefficient (α) values of (20-30) with high breakdown voltages (E B ∼ 400-700 V mm-1). The pentavalent tantalum acts as donor and increases the electronic conductivity. The higher electrical conductivity and decrease in the breakdown field strength with barium addition is attributed to higher density. The acceptor like surface states formed by barium ions segregate to grain boundaries due size misfit to thereby modifying the electrical barrier characteristics of grain boundaries

  6. Plasma irregularities caused by cycloid bunching of the CRRES G-2 barium release

    Science.gov (United States)

    Bernhardt, P. A.; Huba, J. D.; Pongratz, M. B.; Simons, D. J.; Wolcott, J. H.

    1993-01-01

    The Combined Release and Radiation Effects Satellite (CRRES) spacecraft carried a number of barium thermite canisters for release into the upper atmosphere. The barium release labeled G-2 showed evidence of curved irregularities not aligned with the ambient magnetic field B. The newly discovered curved structures can be explained by a process called cycloid bunching. Cycloid bunching occurs when plasma is created by photoionization of a neutral cloud injected at high velocity perpendicular to B. If the injection velocity is much larger than the expansion speed of the cloud, the ion trail will form a cycloid that has irregularities spaced by the product of the perpendicular injection speed and the ion gyroperiod, Images of the solar-illuminated barium ions are compared with the results of a three-dimensional kinetic simulation. Cycloid bunching is shown to be responsible for the rapid generation of both curved and field-aligned irregularities in the CRRES G-2 experiment.

  7. Unexpected finding of barium sulphate on the surface of a microspinal catheter

    International Nuclear Information System (INIS)

    During a study with a scanning electron microscope to evaluate the structure of microspinal catheter after its removal from subarachnoid space, we found an unusual case. The observation with the microscope of the tip of a catheter removed at the end of an operation for hip replacement in a old female showed the presence of grounded particles with a crystal shape covering the outer surface. Further analysis of this material with an Energy-Dispersive Spectrometer (EDS) showed that it was barium. The patient performed a large bowel barium enema 8 months earlier for a painful syndrome to the lower abdomen. Authors rule out the contamination from the skin and suggest two possible mechanisms of passage of barium from blood to cerebrospinal fluid (CSF) and so to the surface of the catheter

  8. Barium sulphate preparations for use in double contrast examination of the upper gastrointestinal tract

    International Nuclear Information System (INIS)

    Physical properties relevant to upper gastrointestinal radiology have been compared for five barium sulphate preparations and related to radiographic results. Evaluation of particles (size and stability) and whole suspension (dispersibility and fluidity) resulted in ranking of the preparations generally in accord with that based on radiological experience in double contrast examinations of the stomach. Experiments with extirpated pig stomach revealed a tendency for large particles in a low viscosity barium sulphate suspension to settle in mucosal grooves. This is believed to contribute to good radiographic definition of both the areae gastricae and small lesions. Particle size is therefore important and susceptibility to flocculation, a possible cause of random change in size during use, was assessed by measuring particle electrophoretic mobility under varying conditions; quantitative differences in suspension flow and dispersibility were also demonstrated. Fluidity and dispersibility together with rapid sedimentation of suitably sized particles resistant to flocculation underlie the successful use of low viscosity high density barium sulphate suspensions. (U.K.)

  9. Barium and strontium sulfate solid solution formation in relation to North Sea scaling problems

    International Nuclear Information System (INIS)

    This paper presents the results of laboratory experiments carried out to investigate barium sulphate and strontium sulphate solid solution formation in multi-pressure tapped cores. Two brines, one barium and strontium rich and the other sulphate rich, were mixed in a core plug. Pressure differentials were measured and the changing permeability distribution along the length of the core calculated. The morphology and chemical analysis of scaling crystals are presented based on Scanning electron Microsocpy (SEM) and Energy Dispersive X-ray Analysis (EDAX). The results show the large extent of permeability damage caused by (Ba, SR) SO/sub 4/ solid solution depositing on the rock pore surface. The rock permeability decline and morphology and size of the scaling crystals indicate the influence of the supersaturations of BaSO/sub 4/ and SrSO/sub 4/ as well as the concentration ratio of barium ions to strontium ions

  10. Therapeutic barium enema for bleeding colonic diverticula:Four case series and review of the literature

    Institute of Scientific and Technical Information of China (English)

    Jun-ichi Iwamoto; Yuji Mizokami; Koichi Shimokobe; Takeshi Matsuoka; Yasushi Matsuzaki

    2008-01-01

    The prevalence of diverticular diseases of the colon, including severe and persistent bleeding in Eastern countries, has increased in the last decades. The bleeding from colonic diverticula is the most common cause of acute lower gastrointestinal bleeding. Herein, we report four cases of severe and persistent bleeding of colonic diverticular disease that could be treated with a high concentration barium enema. These four cases showed a similar pattern of bleeding whose source could not be identified. Colonoscopy revealed fresh blood in the entire colon and many diverticula were noted throughout the colon. No active bleeding source was identified, but large adherent clots in some diverticula were noted. After endoscopic and angiographic therapies failed, therapeutic barium enema stopped the severe bleeding. These patients remained free of re-bleeding in the follow-up period (range 17-35 mo) after the therapy. We report the four case series of therapeutic barium enema and reviewed the literature pertinent to this procedure.

  11. 137Cs contaminated waste disposal in cement factory: Environmental problems

    International Nuclear Information System (INIS)

    In the course of utilization (May-June '91) of aluminum slags polluted by 137Cs at the cement factory Presacementi in Robilante (Cuneo, Italy) and during the following months, samples were taken in particular points of the plant, at fixed frequencies. Samples were analyzed to determine 137Cs concentration. Collected data were used to study the behaviour of the element throughout the process. Emissions and ground level air concentrations were estimated from the available data. Contamination of the manufactured cement were monitored until negligible values of 137Cs concentration were attained

  12. Cesium-137 seasonal balance in the Nemuna River, Lithuania

    International Nuclear Information System (INIS)

    Seasonal variations of 137Cs outflow to the Curonian Gulf from the Nemunas-Neris waters were studied under the non-typical climate conditions of 1996. 137Cs accumulation dominated in the total annual balance of this nuclide in the Nemunas-Neris water system, since high concentrations were characteristic only in the spring flood season. The removal of 137Cs from the Nemunas-Neris River bed was the main process in autumn and winter. Presented data indicate the main inputs and outputs of radioactive pollution in the main water system of Lithuania and show that radionuclide input to Lithuania from Belarus is still important. (author)

  13. Pollution of drug-technical materials by cesium-137

    International Nuclear Information System (INIS)

    Drug-technical raw materials are medicinal plants (flowers, folium, grasses, mushrooms, roots, fruits, berry, kidney, cortex), used in pharmacy. To limit receipt cesium-137 in people body in 1993 in the Republic of Belarus were created 'Temporary permission levels of the cesium-137 radionuclides contents in drug-technical raw materials' were created (TPL-1993). The permission levels of cesium-137 are following: for drug-technical raw material (flowers, folium, grass, mushrooms, roots and other plants parts) - 1850 Bq/kg, for dried up fruits and berries - 2590 Bq/kg. (Author)

  14. Barium hydrogen phosphate/gelatin composites versus gelatin-free barium hydrogen phosphate: synthesis and characterization of properties.

    Science.gov (United States)

    Gashti, Mazeyar Parvinzadeh; Burgener, Matthias; Stir, Manuela; Hulliger, Jürg

    2014-10-01

    Recently, attention has been spent on crystal growth of phosphate compounds in gels for studying the mechanism of in vitro crystallization processes. Here, we present a gel-based approach for the synthesis of barium hydrogen phosphate (BHP) crystals using single and double diffusion techniques in gelatin. The composite crystals were compared with analytical grade BHP powder, single and polycrystalline BHP materials using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), scanning pyroelectric microscopy (SPEM), optical microscopy (OM), thermal gravimetric analysis (TGA) and X-ray diffraction (XRD). FTIR spectra showed surface adsorption of gelatin molecules by using BHP stacked sheets due to CH2 stretching, CH2 bending and amide I vibrations are found in a gelatin content of about 2% determined by dissolution. SEM shows various crystal morphologies of the BHP/gelatin composites forming bundled micro-flakes to irregular bundled needles and spheres different from gel-free crystals. The variety in morphology depends on the ion concentration, pH of gel as well as the method of crystal growth. SPEM investigation of BHP/gelatin aggregates revealed polar domains showing alteration of the polarization. Moreover, BHP/gelatin composite crystals showed a higher thermal stability in comparison with analytical grade BHP or/and BHP single crystals due to strong interactions between gelatin and BHP. The XRD diffraction analysis demonstrated that the single and double diffusion techniques in gelatin led to the formation of orthorhombic BHP. This study demonstrates that gelatin is a useful high molecular weight biomacromolecule for controlling the crystallization of a composite material by producing a variety of morphological forms. PMID:24996024

  15. Thick-target yields of radioactive targets deduced from inverse kinematics

    CERN Document Server

    Aikawa, Masayuki; Imai, Shotaro

    2014-01-01

    The thick-target yield (TTY) of long-lived fission products (LLFP) is an essential quantity and represents basic data for transmutation. In order to evaluate TTY on radioactive targets including LLFP, we suggest a conversion method from inverse kinematics corresponding to the reaction of radioactive beams on stable targets. We demonstrate the method to deduce the TTY from inverse kinematics derived from the theoretical definition. This method is highly applicable in reactions at the energy per nucleon \\epsilon > 20 MeV/A as practically confirmed by the simulation of the SRIM2008 code. In this paper, we apply the method to the natCu(12C,X)24Na reaction to confirm availability. In addition, it is applied to the 137Cs + 12C reaction to reduce 137Cs and to suggest a TTY measurement of the 137Cs induced reaction on a thick 12C target.

  16. Calcium barium niobate as a functional material for broadband optical frequency conversion.

    Science.gov (United States)

    Sheng, Yan; Chen, Xin; Lukasiewicz, Tadeusz; Swirkowicz, Marek; Koynov, Kaloian; Krolikowski, Wieslaw

    2014-03-15

    We demonstrate the application of as-grown calcium barium niobate (CBN) crystal with random-sized ferroelectric domains as a broadband frequency converter. The frequency conversion process is similar to broadband harmonic generation in commonly used strontium barium niobate (SBN) crystal, but results in higher conversion efficiency reflecting a larger effective nonlinear coefficient of the CBN crystal. We also analyzed the polarization properties of the emitted radiation and determined the ratio of d32 and d33 components of the second-order susceptibility tensor of the CBN crystal. PMID:24690779

  17. Study of the microstructural transformations of borate glass and barium metaborate crystals induced by femtosecond laser

    Institute of Scientific and Technical Information of China (English)

    Chen Bin; Yu Bing-Kun; Yan Xiao-Na; Qiu Jian-Rong; Jiang Xiong-Wei; Zhu Cong-Shan

    2004-01-01

    This paper describes the microstructural transformations of borate glass and barium metaborate crystals induced by femtosecond laser. Such structural transformations were verified by Raman spectroscopy. The borate glass is transformed into low temperature (LT) phase of barium metaborate (BaB2O4) crystals after being irradiated for 10 min by a femtosecond laser. In addition, after 20 min of irradiation, high temperature (HT) phase of BaB2O4 crystals is also produced. Further studies demonstrate that LT phase BaB2O4 crystals are formed in the HT phase BaB2O4 crystals after femtosecond laser irradiation for 10 s.

  18. Temperature-Dependent Raman Spectra and Microstructure of Barium Metaborate Crystals and Its Melts

    Institute of Scientific and Technical Information of China (English)

    尤静林; 蒋国昌; 侯怀宇; 吴永全; 陈辉; 徐匡迪

    2002-01-01

    We have measured the Raman spectra of β- and α-barium metaborate in crystal and liquid states from room temperature to 1873K, with a semiconductor laser as the laser source, coupled with a time-resolved detection system to eliminate the dense thermal emission background when temperature was considerably high.Temperature-dependent Raman spectra can clearly indicate that the phase transformation from β- to α-barium metaborate has been completed during 1273 - 1300 K. Variations of different kinds of microstructure units with temperature are identified and discussed.

  19. Synthesis, characterization and thermostability of barium β-diketonate with tetraethylenepentamine ligand

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    The metal-organic chemical vapor deposition (MOCVD) technique is a promising process for high-temperature superconductor YBa2Cu3O7-δ(YBCO) preparation. In this technique, it is a challenge to obtain barium precursors with high volatility. In addition, the purity, evaporation characteristics and thermostability of adopted precursors in the whole process would decide the quality and reproducible results of YBCO film. In the present report, the barium precursor containing 2,2,6,6-tetramethylheptane-3,5-dionate...

  20. Chemical composition of nanomodified composite binder with nano- and microsized barium silicate

    Directory of Open Access Journals (Sweden)

    KOROLEV Evgenij Valerjevich

    2014-08-01

    Full Text Available There are several possibilities to improve cement-based binders. In particular, many properties of cement stone can be enhanced by means of micro- and nanoscale modification. In a number of previous works we had shown that application of barium hydrosilicates leads to such improvement. The present article is devoted to the investigation of the chemical composition of the cement stone which is modified by means of addition of barium hydrosilicates. The modification was performed on different scales: micro- and nanoscale; the results of simultaneous multi-scale modification are also presented. The examination was carried out with help of different modern research techniques – FT IR spectroscopy, differential thermal analysis and X-ray phase analysis. Identification of the new phases and comparative quantitative assessment of their content are performed. It is found that the use of nano- and micro-sized barium hydrosilicates as additives leads to reduction of portlandite by 27...28%; by means of multi-scale modification it is possible to reduce the content of portlandite much more (by 83.3%. Due to addition of nano- and micro-sized barium-based modifiers both the amount of calcium hydrosilicates in reaction products is enlarged, and structure of the mentioned hydrosilicates is changed (the formation of a fine-grained structure of hydration products takes place. Micro-sized barium hydrosilicates are chemically active additives and promote the formation of an additional quantity of calcium hydrosilicates of type CSH (I. The use of nanoscale barium hydrosilicates promotes the formation of CSH (I and CSH (II calcium hydrosilicates, and also both riversidite and xonotlite. As a result of simultaneous application of nano- and micro-sized barium hydrosilicates the content of CSH (II increases. This can be confirmed by means of differential thermal and X-ray analysis. The amount of CSH (I, riversidite and various tobermorites is also increases. It is

  1. Physical states and properties of barium titanate films in a plane electric field

    Science.gov (United States)

    Shirokov, V. B.; Kalinchuk, V. V.; Shakhovoi, R. A.; Yuzyuk, Yu. I.

    2016-07-01

    The influence of a plane electric field on the phase states of barium titanate thin films under the conditions of forced deformation has been studied. The field dependence of a complete set of material constants has been taken in the region of the c-phase, where polarization losses are absent. The material constants are calculated using equations of the piezoelectric effect derived by linearizing the nonlinear equations of state from the phenomenological; theory for barium titanate. It has been shown that there is a critical value of the field at which the electromechanical coupling coefficient reaches a maximum.

  2. Barium meal examination of infants under four months of age presenting with vomiting

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, R.J.; Ziervogel, M.A.; Azmy, A.F.

    1984-02-01

    One hundred barium meal examinations performed on infants of less than 4 months of age are reviewed. All the infants presented with vomiting as a major symptom and the diagnosis remained in doubt following the initial clinical assessment. Fifty seven per cent of the examinations showed an abnormality of which 45% were throught to be significant. Hypertrophic pyloric stenosis was demonstrated in 23 infants. Other abnormalities included hiatus hernia, gastrooesophageal reflux, and duodenal abnormalities. The value of barium meal examinations in this group of infants is emphasised.

  3. Magnetic properties of barium ferrite dispersed within polystyrene-butadiene-styrene block copolymers.

    Science.gov (United States)

    Chipara, M; Skomski, R; Ali, N; Hui, D; Sellmyer, D J

    2009-06-01

    Magnetic properties of nanocomposite materials obtained by dispersing barium ferrite nanoparticles within polystyrene-butadiene-styrene block copolymer, in the temperature range, 300 to 500 K are reported. The temperature dependence of the magnetization at saturation, averaged uniaxial magnetocrystalline anisotropy, and coercive field of thick films are analyzed. A "matrix effect" was noticed within the glass transition range of the hard component (polystyrene) of the polymeric matrix. The reported modifications of the magnetic properties were assigned to the competition between the magnetic and mechanical reorientation of nanoparticles within the polymeric matrix. Such modifications were not observed in barium ferrite dispersed in cement. PMID:19504902

  4. Effects of oleic acid on the high threshold barium current in seabass Dicentrarchus labrax ventricular myocytes

    OpenAIRE

    Chatelier, Aurelien; Imbert, Nathalie; Zambonino, Jose-luis; McKenzie, David; Bois, P.

    2006-01-01

    The present study employed a patch clamp technique in isolated seabass ventricular myocytes to investigate the hypothesis that oleic acid (OA), a mono-unsaturated fatty acid, can exert direct effects upon whole-cell barium currents. Acute application of free OA caused a dose-dependent depression of the whole-cell barium current that was evoked by a voltage step to 0 mV from a holding potential of -80 mV. The derived 50% inhibitory concentration (IC50) was 12.49 +/- 0.27 mu mol l(-1). At a con...

  5. The structural and magnetic properties of barium ferrite powders prepared by the sol-gel method

    Institute of Scientific and Technical Information of China (English)

    Li Jie; Zhang Huai-Wu; Li Yuan-Xun; Liu Ying-Li; Ma Yan-Bing

    2012-01-01

    In this paper,M-type hexagonal barium ferrite powders are synthesized using the sol-gel method.A dried precursor heated in air is analyzed in the temperature range from 50 to 1200 ℃ using thermo-gravimetric analysis and differential scanning calorimetry. The effects of the additives and the cacinating temperature on the magnetic properties are investigated,and the results show that single-phase barium ferrite powders can be formed. After heat-treating at 950 ℃ for 4h with 3 wt% additive,the coercivity and saturation magnetization are found to be 440 Oe and 57.9 emu/g,respectively.

  6. Dielectric properties of piezoelectric 3–0 composites of lithium ferrite/barium titanate

    Indian Academy of Sciences (India)

    P Sarah; S V Suryanarayana

    2003-12-01

    Piezoelectric 3–0 composite ceramics are prepared from a mixture of barium titanate and lithium ferrite phase constituents. Dielectric properties of composites are affected by a number of parameters that include electrical properties, size, shape and amount of constituent phases. The frequency dependent measurements can provide additional insight into mechanisms controlling electrical response. Frequency dependence of dielectric constant plots of lithium ferrite/barium titanate composites will be given and the relevance of trends seen in them will be discussed. Connectivity in composites developed is studied.

  7. Features of Raman amplification in KGW and barium nitrate crystals at excitation by femtosecond pulses

    International Nuclear Information System (INIS)

    Measurements of Raman amplification in KGd(WO4)2 (KGW) and barium nitrate crystals at femtosecond excitation demonstrate spectral transformation of amplification band with change of pump parameters. The half-height amplification bandwidth of up to 45 nm (650 cm-1) what is 5 times larger than the pumping pulse spectral band 8.5 nm (130 cm-1) was observed for KGW crystal. Implementation of impulsive excitation for the low-frequency vibrations allows estimations of the dephasing times and linewidths for the 87 and 83 cm-1 Raman lines in KGW and barium nitrate

  8. Research and analysis on the thin films sputtered by the Ba-Al-S:Eu target fabricated by powder sintering

    Science.gov (United States)

    Zhang, Dongpu; Xu, Fang; Yu, Zhinong; Xue, Wei

    2014-11-01

    Europium-doped barium thioaluminate (BaAl2S4:Eu) is currently the most efficient blue phosphor for inorganic thin film electroluminescent (iEL) device. To produce the full-color EL device, several kinds of blue-emitting layer were attempted and tested. As a key point of blue-emitting layer fabrication, single target sputtering deposition is an effective method. In this work, new structural target is introduced and the fabricated process is expatiated. The PL spectra of as fabricated targets show that both of two, 3mol% and 5mol% europium-doped, have blue emitting property. According to the PL spectra excited by 290nm, 300nm and 320nm ultraviolet, emission peaks located in the region near 470nm. So the as-fabricated targets can be used in single target sputtering deposition on thin film of BaAl2S4:Eu. XRD pattern indicates that there are 4 different phases, barium tetraaluminum sulfide (BaAl4S7), barium sulfide (BaS), europium sulfide (EuS) and barium aluminum oxide (BaAl2O4), in target 1. Besides these four compounds, other two phases, aluminum sulfide (Al2S3) and barium thioaluminate (BaAl2S4), are detected in target 2. Considering the analysis results, especially the hydrolyzation of Al2S3, target 1 is more suitable for sputtering deposition of BaAl2S4:Eu thin film. XPS and X-ray Fluorescence patterns describe the precise molar ratio of each element. In target 1 the relative atom concentration of barium, aluminum, sulfur and oxygen can be calculated from the pattern and molar ratio is about 9:33:41:17. Molar ratio of barium and europium is about 1:0.03. In short, the barium thioaluminate doped by europium sputtering target 1 is better to be applied in the fabrication of blue-emitting layer in inorganic electro-luminescent devices.

  9. Long-term behaviour of 137Cs in Finnish lakes

    International Nuclear Information System (INIS)

    Deposition of 137Cs from Chernobyl accident was unevenly distributed in Finland. This caused large variation to contents of 137Cs in freshwater fish in Finnish lakes. In the course of time environmental processes like runoff, water flow, hydrological cycling, sedimentation and chemical parameters as e.g., K of lake water, topography of the catchment affect the transfer of 137Cs in water sheds. Most of the Finnish lakes are deficient in nutrients and hence the accumulation of 137Cs into fishes is high. High amount of humic substances is also typical of Finnish lakes. About 6000 freshwater fish samples from 350 Finnish lakes have been analysed for 137Cs in 1986-2003. Sampling was focused on the central parts of Finland with highest deposition of 137Cs, but samples from other areas were also analysed. Large lakes, most important for freshwater fishing in Finland, and small oligotrophic lakes, in which the highest contents of 137Cs were expected to be found, were included in the study. Variation range of 137Cs in fish was still in 2003 large, from 5 Bq/kg to 5000 Bq/kg (fresh weight). Water samples from about 30 lakes were taken in 1998 and 2002 and analysed for 137Cs. Contents of 137Cs in lake waters varied then from 4 to 330 Bq/m3. During the first years after the deposition in 1986, the amount of the deposited 137Cs in the lake was the dominant factor on the distribution of 137Cs in fish and surface water. Later study on regional behaviour of 137Cs in fish revealed differences in decrease rates in the large drainage areas [2]. Temporal changes of 137Cs in water and especially in fish in individual lakes of various types, even in those located close to each other, differ still much. Transfer coefficients of 137Cs from the deposition to water, TFw (Bq/m3 in water/kBq/m2 deposited) of the lakes included in this study varied from 0,40 to 8,7 in 1998. Transfer factors from the deposition to various species of fish from various lakes, TFf (Bq/kg in fish / Bq/m2), varied

  10. Patterns of cesium-137 distribution across two disparate floodplains

    International Nuclear Information System (INIS)

    Soil 137Cs concentration was studied across upstream and downstream floodplain sites of Lower Three Runs Creek, an Upper Coastal Plain stream draining a portion of the Savannah River Plant. Soil samples were collected laterally and vertically at each floodplain location and analyzed for several edaphic characteristics. The results showed that these floodplains were differentiable by their edaphic characteristics both between sites and between depths within a site. The surface distribution of 137Cs was related to microtopographic variation at each site, but predictive relationships for estimating surface-soil 137Cs content from edaphic parameters were not as well defined. A difference in upstream to downstream 137Cs cycling was explained on the basis of the change from direct to indirect nutrient cycling pathways in a downstream direction. This change was coincident with higher sedimentation, greater cation adsorptive capacity, and higher potassium concentrations found downstream

  11. Growth rate controlled barium partitioning in calcite and aragonite

    Science.gov (United States)

    Goetschl, Katja Elisabeth; Mavromatis, Vasileios; Baldermann, Andre; Purgstaller, Bettina; Dietzel, Martin

    2016-04-01

    The barium (Ba) content and the Ba/Ca molar ratios in biogenic and abiotic carbonates have been widely used from the scientific community as a geochemical proxy especially in marine and early diagenetic settings. The Ba content of carbonate minerals has been earlier associated to changes in oceanic circulation that may have been caused by upwelling, changes in weathering regimes and river-runoff as well as melt water discharge. The physicochemical controls of Ba ion incorporation in the two most abundant CaCO3 polymorphs found in Earth's surface environments, i.e. calcite and aragonite, have adequately been studied only for calcite. These earlier studies (i.e. [1]) suggest that at increasing growth rate, Ba partitioning in calcite is increasing as well. In contrast, to date the effect of growth rate on the partitioning of Ba in aragonite remains questionable, despite the fact that this mineral phase is the predominant carbonate-forming polymorph in shallow marine environments. To shed light on the mechanisms controlling Ba ion uptake in carbonates in this study we performed steady-state Ba co-precipitation experiments with calcite and aragonite at 25°C. The obtained results for the partitioning of Ba in calcite are in good agreement with those reported earlier by [1], whereas those for aragonite indicate a reduction of Ba partitioning at elevated aragonite growth rates, with the partitioning coefficient value between solid and fluid to be approaching the unity. This finding is good agreement with the formation of a solid solution in the aragonite-witherite system, owing to the isostructural crystallography of the two mineral phases. Moreover, our data set provides new insights that are required for reconstructing the evolution of the Ba content of pristine marine versus diagenetically altered carbonate minerals commonly occurring in marine subfloor settings, as the thermodynamically less stable aragonite will transform to calcite enriched in Ba, whilst affecting

  12. Strontium-90 and cesium-137 in tea (Japanese tea)

    International Nuclear Information System (INIS)

    Sr-90 and Cs-137 in Japanese tea were determined using radiochemical analysis. Five hundred grams of manufactured green tea was collected from six sampling locations in June 1984, carbonized and ashed in a stainless steel pan or a porcelain dish. The maximum value of Sr-90 was 88+-3.7 pCi/kg in tea collected from Kyoto; the maximum value of Cs-137 was 99.0+-3.60 pCi/kg collected from Kagoshima. (Namekawa, K.)

  13. Obsah Cs-137 v houbách

    OpenAIRE

    ČADOVÁ, Michaela

    2015-01-01

    The aim of this work is to compare the presence of Cs-137 in different kinds of mushrooms in selected locations using semiconductor gamma-ray spectrometry. Research question was determined: Does Cs-137 content amount vary depending on the fungal species? The first part deals with basic knowledge of ionizing radiation, which is important for the complex understanding of thematic problems. This concerns basic radiobiological terms such as radioactivity, ionizing radiation, its biological effect...

  14. Estimation of erosion rate using natural isotop 137Cs

    International Nuclear Information System (INIS)

    The investigation of erosion rate using natural isotope 137Cs had been done in hilliness area at GOULBURN-NWS-Australia. The presentation of 137Cs in natural was as a result of nuclear weapon testing in the middle of 1950's. Fallout of 137Cs input, when it reached the ground, it rapidly adsorbed at the soil. 137Cs bind very strong at the fine soil, so it can be used as tracer in the study of soil movement. Soil samples were taken using coring device (di=10 cm, h=20 cm), and were brought to laboratorium for short commun analysis. The preparation are drying, weighing, crushing and sieving. The 137Cs content of fine samples that pass the 1 mm sieve were analyzed using gamma-spectrometer. The total erosion rate was calculate by ploting the 137Cs values in the topography map of study area. The result showed that erosion was very low, and total erosion rate is 130 kg/ha.y. (authors)

  15. Transfer of 137Cs through the food chain to man

    International Nuclear Information System (INIS)

    Deposition, concentrations in diet, and body burdens of 137Cs have been measured since 1954 at various sites throughout the world. This report is a compilation and updating of various fallout 137Cs measurements and an interpretation of transfer properties of 137Cs from deposition to diet and from diet to man. An empirical model is used to correlate deposition and diet data. Direct foliar contamination, stored food supplies, and uptake from soil contribute to the dietary levels of 137Cs. The accumulation of 137Cs by man is described by a single exponential model. The inferred biological half-times, 200 to 400 days, are somewhat greater than the half-time of about 100 days obtained from shorter term studies. Differences in body burdens due to sex, age, and weight are discussed. During the period 1954 to 1974, the internal dose from fallout 137Cs, based on average body burdens, is estimated to be 4 to 5 percent of the 21 year radiation dose from 40K

  16. Cs-137 and Sr-90 level in diary products

    Science.gov (United States)

    Petukhov, V. L.; Gorb, T. S.; Petukhov, I. V.; Dukhanov, Yu. A.; Sevryuk, I. Z.; Patrashkov, S. A.; Korotkevich, O. S.

    2003-05-01

    About 70% of radioactive substances fell on the territory of the Byelorussia Republic after the Chernobyl Atom Power Station Disaster. Cs-137 and Sr-90 accumulation dynamics was studied in milk of the cows from the highest polluted Braginsky area. 408 milk samples of Black and White cows were investigated. In 1995 average Cs-137 and Sr-90 levels were 61.00 and 3.73 Bk/dm^3 respectively. Cs-137 and Sr-90 levels exceeded Byelorussia Republic upperlimits RDU 96 in 10 and 50% of milk samples respectively. After 5 years (by 2000) Cs-137 and Sr-90 levels had become almost 3 and 2 times less (21.70 Bk/dm^3 and 1.72 Bk/dm^3 respectively). Cs-137 and Sr-90 levels exceeded RDU 96 in 1.5 and 5.5% of milk samples respectively. In the same periods Cs-137 and Sr-90 levels were 7 and 2 times higher than the similar indexes in the relatively clean Novosibirsk area. Thus, radioactive element levels in milk of Black and White cows of the Byelorussia Republic decreased significantly for the past years.

  17. Cs-137 and Sr-90 level in diary products

    Energy Technology Data Exchange (ETDEWEB)

    Petukhov, V.L.; Dukhanov, Y.A.; Sevryuk, I.Z.; Patrashkov, S.A.; Korotkevich, O.S. [State Agrarian University, Research Institute of Veterinary Genetics and Animal Breeding of Novosibirsk (Russian Federation); Gorb, T.S.; Petukhov, I.V. [Vitebsk State Academy of Veterinary Medicine, Balarus (Russian Federation)

    2003-05-01

    About 70% of radioactive substances fell on the territory of the Byelorussian Republic after the Chernobyl Atom Power Station Disaster. Cs-137 and Sr-90 accumulation dynamics was studied in milk of the cows from the highest polluted Braginsky area. 408 milk samples of Black and White cows were investigated. In 1995 average Cs-137 and Sr-90 levels were 61.00 and 3.73 Bk/dm{sup 3} respectively. Cs-137 and Sr-90 levels exceeded Byelorussian Republic upper limits RDU - 96 in 10 and 50% of milk samples respectively. After 5 years (by 2000) Cs-137 and Sr-90 levels had become almost 3 and 2 times less (21.70 Bk/dm{sup 3} and 1.72 Bk/dm{sup 3} respectively). Cs-137 and Sr-90 levels exceeded RDU - 96 in 1.5 and 5.5% of milk samples respectively. In the same periods Cs-137 and Sr-90 levels were 7 and 2 times higher than the similar indexes in the relatively clean Novosibirsk area. Thus, radioactive element levels in milk of Black and White cows of the Byelorussian Republic decreased significantly for the past years. (authors)

  18. Specific activity 137Cs at fishes of Ukraine current state

    International Nuclear Information System (INIS)

    Specific activity of 137Cs at fishes of reservoirs of 30 kilometers ChNPP zone (Pripyat river and its bays, lakes, cool-ing-pond of ChNPP, etc.), water basins of Dneprovsky cascade, Shatsky lakes and Black sea near town Sudak is investigated during 2010 - 2012. Levels of specific activity of 137Cs at fishes in many respects are defined by flowage of the reservoir. Normally, the flowage of the reservoir is more, the levels of specific activity of 137Cs at fishes are less. The greatest specific activity of 137Cs at fishes was registered in the north of Ukraine in closed and half-closed reservoirs of 30 kilometers ChNPP zone - to 32000 Bqk/kg. In the southern direction activity of 137Cs at fishes decreases from 4,8 to 78,5 Bq/kg in Kyiv water basin to 1 - 6 Bq/kg, in the Kahovsky water basin and to 0,6 - 1,9 Bq/kg in the Black sea. In large reservoirs the greatest specific activity of 137Cs, as a rule, is registered in fishes of the higher trophic levels

  19. Regeneration of barium carbonate from barium sulphide in a pilot-scale bubbling column reactor and utilization for acid mine drainage.

    Science.gov (United States)

    Mulopo, J; Zvimba, J N; Swanepoel, H; Bologo, L T; Maree, J

    2012-01-01

    Batch regeneration of barium carbonate (BaCO(3)) from barium sulphide (BaS) slurries by passing CO(2) gas into a pilot-scale bubbling column reactor under ambient conditions was used to assess the technical feasibility of BaCO(3) recovery in the Alkali Barium Calcium (ABC) desalination process and its use for sulphate removal from high sulphate Acid Mine Drainage (AMD). The effect of key process parameters, such as BaS slurry concentration and CO(2) flow rate on the carbonation, as well as the extent of sulphate removal from AMD using the recovered BaCO(3) were investigated. It was observed that the carbonation reaction rate for BaCO(3) regeneration in a bubbling column reactor significantly increased with increase in carbon dioxide (CO(2)) flow rate whereas the BaS slurry content within the range 5-10% slurry content did not significantly affect the carbonation rate. The CO(2) flow rate also had an impact on the BaCO(3) morphology. The BaCO(3) recovered from the pilot-scale bubbling column reactor demonstrated effective sulphate removal ability during AMD treatment compared with commercial BaCO(3). PMID:22233912

  20. Preventing or reducing the Cs-137 burden in children

    International Nuclear Information System (INIS)

    Full text: The Helsinki Agreements impose intervention when a diagnosed disease can be cured or prevented. Since 1998 members of IPPNW Switzerland study health related problems due to the Chernobyl Fallout in the Ukraine and Belarus. The organisation furthermore finances diagnostic and radiometric activities, as measuring the Cs-137 burden in the organism. Also preventive measures are supported in cooperation with the french NGO 'Children of Chernobyl Belarus'. The Clinical Research Institute of Radiation Medicine and Endocrinology and the Gomel' State Med. Institute found correlations between chronic excess of Cs-137 and genetic, congenital, endocrine, immunological, cardiovascular, gastrointestinal, ophthalmologic anomalies and cancer. For etiological assessment the correlation between pathology and internal irradiation requires repeated measuring of Cs-137 burden. Anthropo-Gammametry measures of the mean Cs-137 load of the organism, which can be done in a few minutes. These values, however, cannot be used to directly calculate the dose to a given organ, as cesium concentrations may vary from 1 to 100 in the same child. Very low values of Cs-137 are found in skin and fatty tissue; in small children the highest concentrations are found in endocrine glands, pancreas, thymus and heart. Cs-137 is a gamma and beta emitting isotope. Whereas in the environment gamma emissions are important, once ingested beta emissions within millimeter distance are more damaging for cellular structures than gamma rays. Neurons of given brain structures localized in the left hemisphere (in right handed persons) also seem to be susceptible to ionizing radiations. There appear to be correlations with certain mental diseases and disorders, including schizophrenia and chronic fatigue syndrome. As regards to practical radiation protection, unfortunately families in rural areas rely on their own foodstuffs and milk and poor families frequently consume highly contaminated natural products. In

  1. Barium and neodymium isotopic anomalies in the Allende meteorite

    Science.gov (United States)

    Mcculloch, M. T.; Wasserburg, G. J.

    1978-01-01

    The discovery of Ba and Nd isotopic anomalies in two inclusions from the Allende meteorite is reported. The inclusions are Ca-Al-rich objects typical of the type considered as high-temperature condensation products in the solar nebula and contain distinctive Mg and O isotopic anomalies of the FUN (mass Fractionation, Unknown Nuclear processes) type. Mass-spectrometry results are discussed which show that inclusion C1 has anomalies in Ba at masses 134 and 136, while inclusion EK1-4-1 exhibits large marked negative anomalies at 130, 132, 134, and 136, as well as a positive anomaly at 137. It is also found that inclusion EK1-4-1 shows marked negative anomalies in Nd at masses 142, 146, 148, and 150, in addition to a positive anomaly at 145. These isotopic shifts are attributed to addition of r-process nuclei rather than mass fractionation. It is suggested that an onion-shell supernova explosion followed by injection into the solar nebula is the most likely generic model that may explain the observations.

  2. Synthesis and characterization of barium titanate, doped with europium and neodymium

    International Nuclear Information System (INIS)

    This work aims at synthesize and characterize mixed oxides in Barium Titanium matrix in doping with Neodymium and Europium analyzing thermogravimetric curves, characteristic bands at infrared region of the polymer complex, which are intermediates to mixed oxides, and identify the formation thereof, and the crystallinity using XRD analysis

  3. Seasonal variability in the input of lead, barium and indium to Law Dome, Antarctica

    DEFF Research Database (Denmark)

    Burn-Nunes...[], L.J.; Vallelonga, Paul Travis; Loss, R.D.;

    2011-01-01

    Lead (Pb) isotopic compositions and concentrations, and barium (Ba) and indium (In) concentrations have been determined at monthly resolution in five Law Dome (coastal Eastern Antarctica) ice core sections dated from similar to 1757 AD to similar to 1898 AD. 'Natural' background Pb concentrations...

  4. A plasmonic modulator based on metal-insulator-metal waveguide with barium titanate core

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Lavrinenko, Andrei

    2013-01-01

    We design a plasmonic modulator which can be utilized as a compact active device in photonic integrated circuits. The active material, barium titanate (BaTiO3), is sandwiched between metal plates and changes its refractive index under applied voltage. Some degree of switching of ferroelectric...

  5. Diffuse X-ray scattering and far infrared absorption of barium and lead β" aluminas

    DEFF Research Database (Denmark)

    Hayes, W.; Kjær, Kristian; Pratt, F. L.;

    1985-01-01

    The authors have carried out high-momentum-resolution studies in diffuse X-ray scattering of barium and lead B" aluminas in the temperature range 20-700 degrees C. They have also measured the vibrational spectra of these compounds between 2K and 300K in the energy range 10-100 cm-1. The results...

  6. The Precipitation Process of Liquid Wastes Containing Contaminant Am withBarium Sulfate

    International Nuclear Information System (INIS)

    The investigated of the reduction volume liquid wastes containing ofAmericium nuclide contaminant has been done. The reduction volume was done byadding barium sulfate coagulant. The experimental procedure that has beendone by adding regent of barium nitrate and natrium sulfate to the wasteswith its preadjusted pH, then by utilizing the jar test equipment was carriedout the fast stirring speed for 5 minutes and the gentle agitation for 30minutes, therefor its floc and supernatant will be formed. The resultedbarium sulfate floc will trap radionuclide in the wastes. The Variableinvestigated were: the concentration of barium sulfate, pH of the wastes, theflash mixing rate, the gentle agitation rate. The investigated barium sulfateconcentration variable was started from 100 ppm up to 800 ppm. Theinvestigated pH variable was started from pH 7 up to pH 13. The investigatedflash mixing rate were 75, 100, 125, 150, 175, 200, 225, 250 rpm. Theinvestigated gentle agitation variable were 20, 30, 40, 50 rpm. The bestresult which was represented by decontaminating factor (DF) was found frombarium sulfate concentration of 300 ppm and pH 11, and the flash mixing rateof 200 rpm and the gentle agitation rate of 20 rpm, with the separationefficiency = 97.2 %. (author)

  7. Study of structural, ferromagnetic and ferroelectric properties of nanostructured barium doped Bismuth Ferrite

    International Nuclear Information System (INIS)

    Nanostructured multiferroic Bi(1−x)BaxFeO3x=0.0, 0.1, 0.2 were prepared by hydrothermal technique. All samples belonged to the rhombohedrally distorted perovskite structure. The morphology of the particles changed with the doping of barium. Effect of barium doping on the dielectric constant was studied over a wide frequency range of 1000 Hz–1 MHz. The activation energy due to relaxation and due to conduction was measured from the Cole Cole plot and the AC conductivity versus frequency plot respectively. The activation energy estimated from both the studies was close to each other. The activation energy also enhanced with the increase in the barium content. The magnetization at the highest available field (∼1.6 T) increased from 0.05 emu/g for the sample with x=0.0–12 emu/g for the sample with x=0.2. The magnetic measurements show a significant increase in magnetization around 400 °C. Remnant polarization for x=0.0 was negligible and it increased to 0.06 µC/cm2 for x=0.2. - Highlights: • Bismuth Ferrite nanostructures were synthesized by the hydrothermal technique. • Barium was doped in Bismuth site. • Morphology changed with doping. • Ferromagnetic, Ferroelectric and Dielectric properties enhanced with doping. • An unreported magnetic transition due to spin canting was observed near 550 °C

  8. Adsorption of Pb(II) present in aqueous solution on calcium, strontium and barium hydroxy apatites

    International Nuclear Information System (INIS)

    Calcium, strontium and barium hydroxy apatites were successfully synthesized by chemical precipitation method, the obtained powders were characterized by the techniques of X-ray diffraction (XRD), scanning electron microscopy (Sem), semi-quantitative elemental analysis (EDS), infrared spectroscopy (IR), and N2 physisorption studies, complementary to these analytical techniques, was determined the surface fractal dimension (Df), and the amount of surface active sites of the materials, in order to know application as ceramic for water remediation. The ability of Pb(II) ion adsorption present in aqueous solution on the hydroxy apatites synthesized by batch type experiments was studied as a function of contact time, concentration of the adsorbate and temperature. The maximum lead adsorption efficiencies obtained were 0.31, 0.32 and 0.26 mg/g for calcium, strontium and barium hydroxy apatites respectively, achieved an equilibrium time of 20 minutes in the three solid-liquid systems studied. Experimental data were adequately adjusted at the adsorption kinetic model pseudo-second order, for the three cases. Moreover, experimental data of the strontium and calcium hydroxy apatites were adjusted to the Langmuir adsorption isotherm, indicating that the adsorption was through a monolayer, whereas barium hydroxyapatite was adjusted to the Freundlich adsorption isotherm, indicating a multilayer adsorption. The thermodynamic parameters obtained during adsorption studies as a function of temperature showed physisorption, exothermic and spontaneous processes respectively. The results showed that the calcium hydroxyapatite, strontium and barium are an alternative for the Pb(II) ion adsorption present in wastewaters. (Author)

  9. A comparison of radiographer and radiologist reports on radiographer conducted barium enemas

    International Nuclear Information System (INIS)

    Purpose: To compare radiographer and radiologist reports on radiographer conducted barium enemas. Method: Two specially trained, experienced radiographers performed barium enemas and prepared provisional reports without consulting radiologists. Later, formal radiologist reports were issued. The reports of each were compared and correlated with clinical findings derived from case note review. Results:Seven hundred and eighty eight patients had barium enemas. Males numbered 295 (37.5%) and females 493 (62.5%). Patients ages ranged from 17 to 95 years (mean 62). The radiologist reported 244 as normal, 432 as diverticular change, 70 with polyps (31 of which had co-existent diverticular disease), 31 with carcinomas and 12 with colitis (three of which had co-existent diverticular disease). Taking the radiologist reports as gold-standard radiographer reports were concordant in 753 (95.5%). There were 35 (4.5%) discordant radiographer reports of these 19 were false-positive diagnoses of polyps and six false positive diagnoses of diverticular change. There were seven false-negative diagnoses of polyps (only one of these was found to have a polyp at follow-up endoscopy). There was one false-negative diagnosis of colitis and two false-negative reports of diverticular change. On follow up there were no false negative diagnoses of carcinoma by either radiographer or radiologist. There was one concordant false-positive diagnosis of carcinoma. Conclusion:Radiographers with specialized training can report barium enemas to a high standard

  10. Spectroscopic (multi-energy) CT distinguishes iodine and barium contrast material in MICE

    CERN Document Server

    Anderson, NG; Firsching, M; de Ruiter, N; Schleich, N; Butzer, J S; Cook, N J; Grasset, R; Campbell, M; Scott, N J A; Anderson, N G

    2010-01-01

    Spectral CT differs from dual-energy CT by using a conventional X-ray tube and a photon-counting detector. We wished to produce 3D spectroscopic images of mice that distinguished calcium, iodine and barium. We developed a desktop spectral CT, dubbed MARS, based around the Medipix2 photon-counting energy-discriminating detector. The single conventional X-ray tube operated at constant voltage (75 kVp) and constant current (150 A mu A). We anaesthetised with ketamine six black mice (C57BL/6). We introduced iodinated contrast material and barium sulphate into the vascular system, alimentary tract and respiratory tract as we euthanised them. The mice were preserved in resin and imaged at four detector energy levels from 12 keV to 42 keV to include the K-edges of iodine (33.0 keV) and barium (37.4 keV). Principal component analysis was applied to reconstructed images to identify components with independent energy response, then displayed in 2D and 3D. Iodinated and barium contrast material was spectrally distinct f...

  11. Physical and biological dosimetry at the barium sulphate-culture medium interface

    International Nuclear Information System (INIS)

    The present study suggests that a thin layer of Barium sulphate suspension forms an interface with tissues which results in high dose regions on both sides of the BSS-tissue interface when irradiated with 250 kVp X rays. The magnitude of dose increase depends on the density of the BSS. (U.K.)

  12. Assessment of barium sulphate formation and inhibition at surfaces with synchrotron X-ray diffraction (SXRD)

    International Nuclear Information System (INIS)

    The precipitation of barium sulphate from aqueous supersaturated solutions is a well-known problem in the oil industry often referred to as 'scaling'. The formation and growth of barite on surfaces during the oil extraction process can result in malfunctions within the oil facilities and serious damage to the equipment. The formation of barium sulphate at surfaces remains an important topic of research with the focus being on understanding the mechanisms of formation and means of control. In situ synchrotron X-ray diffraction (SXRD) was used to investigate the formation of barium sulphate on a stainless steel surface. The effect of Poly-phosphinocarboxylic acid (PPCA) and Diethylenetriamine-penta-methylenephosphonic acid (DETPMP) which are two commercial inhibitors for barium sulphate was examined. The in situ SXRD measurements allowed the identification of the crystal faces of the deposited barite in the absence and presence of the two inhibitors. The preferential effect of the inhibitors on some crystal planes is reported and the practical significance discussed.

  13. Study of structural, ferromagnetic and ferroelectric properties of nanostructured barium doped Bismuth Ferrite

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhuri, A., E-mail: arkac123@gmail.com [Department of Applied Science, Haldia Institute of Technology, Dist.- Purba Medinipur, Haldia- 721657, West Bengal (India); Department of Condensed Matter Physics and Material Science, S.N. Bose National Center for Basic Sciences, Block JD, Salt Lake, Kolkata 700098 (India); Mandal, K. [Department of Applied Science, Haldia Institute of Technology, Dist.- Purba Medinipur, Haldia- 721657, West Bengal (India); Department of Condensed Matter Physics and Material Science, S.N. Bose National Center for Basic Sciences, Block JD, Salt Lake, Kolkata 700098 (India)

    2014-03-15

    Nanostructured multiferroic Bi{sub (1−x)}Ba{sub x}FeO{sub 3}x=0.0, 0.1, 0.2 were prepared by hydrothermal technique. All samples belonged to the rhombohedrally distorted perovskite structure. The morphology of the particles changed with the doping of barium. Effect of barium doping on the dielectric constant was studied over a wide frequency range of 1000 Hz–1 MHz. The activation energy due to relaxation and due to conduction was measured from the Cole Cole plot and the AC conductivity versus frequency plot respectively. The activation energy estimated from both the studies was close to each other. The activation energy also enhanced with the increase in the barium content. The magnetization at the highest available field (∼1.6 T) increased from 0.05 emu/g for the sample with x=0.0–12 emu/g for the sample with x=0.2. The magnetic measurements show a significant increase in magnetization around 400 °C. Remnant polarization for x=0.0 was negligible and it increased to 0.06 µC/cm{sup 2} for x=0.2. - Highlights: • Bismuth Ferrite nanostructures were synthesized by the hydrothermal technique. • Barium was doped in Bismuth site. • Morphology changed with doping. • Ferromagnetic, Ferroelectric and Dielectric properties enhanced with doping. • An unreported magnetic transition due to spin canting was observed near 550 °C.

  14. Barium versus Nonbarium Stimuli: Differences in Taste Intensity, Chemesthesis, and Swallowing Behavior in Healthy Adult Women

    Science.gov (United States)

    Nagy, Ahmed; Steele, Catriona M.; Pelletier, Cathy A.

    2014-01-01

    Purpose: The authors examined the impact of barium on the perceived taste intensity of 7 different liquid tastant stimuli and the modulatory effect that these differences in perceived taste intensity have on swallowing behaviors. Method: Participants were 80 healthy women, stratified by age group (60) and genetic taste status…

  15. Low temperature phase barium borate: A new optical limiter in continuous wave and nano pulsed regime

    Science.gov (United States)

    Babeela, C.; Girisun, T. C. Sabari

    2015-11-01

    Low temperature phase barium borate was synthesized by hydrothermal method. XRD analysis confirms the formation of γ-BBO or hydrated barium polyborate (Ba3B6O9(OH)6) which crystallizes in monoclinic system in the P2/c space group. The molecular structure analysis shows the presence of dominant BO4 unit and the hydrated nature of material. γ-BBO exhibits sharp absorption edge at 202 nm and highly transparency in the UV-Visible-NIR region. The peak at 347 nm in the emission spectrum is due to the presence of self-trapped exciton. The third order nonlinear optical properties and limiting behavior of low temperature barium borate in both pulsed and continuous wave regime were studied. The effective 2PA absorption coefficient of γ-BBO under ns pulse excitation is estimated to be 0.38 × 10-10 m/W. The nonlinear absorption coefficient, refractive index and optical susceptibility of the material in cw regime were found to be in the order of 10-5 m W-1, 10-12 m2 W-1, 10-6 esu respectively. In both regimes, low temperature phase barium borate exhibits better optical limiting properties than high temperature phase β-BBO.

  16. Barium borosilicate glass as a matrix for the uptake of dyes

    International Nuclear Information System (INIS)

    Barium borosilicate (BBS) and sodium borosilicate (SBS) glass samples, prepared by the conventional melt-quench method, were used for the uptake of Rhodamine 6G dye from aqueous solution. The experimental conditions were optimized to get maximum uptake and was found to be 0.4 mg of dye per gram of BBS glass sample. For the same network former to modifier ratio, barium borosilicate glasses are found to have improved extent of uptake for the dye molecules from aqueous solutions compared to sodium borosilicate glasses. Based on 29Si MAS NMR studies on these glasses, it is inferred that significantly higher number of non-bridging oxygen atoms present in barium borosilicate glasses compared to sodium borosilicate glasses is responsible for its improved uptake of Rhodamine 6G dye. 11B MAS NMR studies have confirmed the simultaneous existence of boron in BO3 and BO4 configurations in both barium borosilicate and sodium borosilicate glasses. The luminescence studies have established that the dye molecule is incorporated into the glass matrix through ion exchange mechanism by replacing the exchangeable ions like Na+/Ba2+ attached with the non-bridging oxygen atoms present in the glass.

  17. MIR137HG risk variant rs1625579 genotype is related to corpus callosum volume in schizophrenia

    NARCIS (Netherlands)

    Patel, V.S.; Kelly, S.; Wright, C.; Gupta, C.N.; Arias Vasquez, A.; Perrone-Bizzozero, N.; Ehrlich, S.; Wang, L.; Bustillo, J.R.; Morris, D.; Corvin, A.; Cannon, D.M.; McDonald, C.; Donohoe, G.; Calhoun, V.D.; Turner, J.A.

    2015-01-01

    Genome-wide association studies implicate the MIR137HG risk variant rs1625579 (MIR137HGrv) within the host gene for microRNA-137 as a potential regulator of schizophrenia susceptibility. We examined the influence of MIR137HGrv genotype on 17 subcortical and callosal volumes in a large sample of indi

  18. Possible discovery of the r-process characteristics in the abundances of metal-rich barium stars

    CERN Document Server

    Cui, W Y; Shi, J R; Zhao, G; Wang, W J; Niu, P

    2014-01-01

    We study the abundance distributions of a sample of metal-rich barium stars provided by Pereira et al. (2011) to investigate the s- and r-process nucleosynthesis in the metal-rich environment. We compared the theoretical results predicted by a parametric model with the observed abundances of the metal-rich barium stars. We found that six barium stars have a significant r-process characteristic, and we divided the barium stars into two groups: the r-rich barium stars ($C_r>5.0$, [La/Nd]\\,$<0$) and normal barium stars. The behavior of the r-rich barium stars seems more like that of the metal-poor r-rich and CEMP-r/s stars. We suggest that the most possible formation mechanism for these stars is the s-process pollution, although their abundance patterns can be fitted very well when the pre-enrichment hypothesis is included. The fact that we can not explain them well using the s-process nucleosynthesis alone may be due to our incomplete knowledge on the production of Nd, Eu, and other relevant elements by the ...

  19. Clinical analysis of intestinal colostomy closure operation in 137 cases%肠造口还纳手术137例临床分析

    Institute of Scientific and Technical Information of China (English)

    张军

    2014-01-01

    Objective To investigate the operation time and operation mode of colostomy closure,and the prevention and treatment of complications occurred. Methods The clinical data of 137 patients with colostomy closure operation were retrospec-tively analyzed,and the colostomy stoma reason and method,closured time,postoperative complications and preventive treatment was statistical analyzed. Results Stoma causes including low rectal cancer low anastomosis proximal protective stoma in 57 ca-ses,63 cases of colon injury,9 cases of anastomotic leakage,8 cases of Crohn′s disease and familial polyposis. The average time was 162. 3 days;preoperative examination of colonoscopy in 117 cases and barium enema in 20 cases;Stapler anastomosis in 122 cases and manual reduction in 15 cases. Side-to-side anastomosis in 106 cases,end-to-end anastomosis in 21 cases,end to side anastomosis in 10 cases. Complications occurred in 13 patients(9. 5%),including 2 cases of anastomotic leakage,re-ileostomy in 1 case;wound infection in 4 cases,intestinal obstruction in 2 cases,abdominal cavity infection in 2 cases,anastomotic bleed-ing in 1 case,partial abdominal wall hematoma in 1 case. Postoperative average time was 12. 7 days. Conclusion Before colos-tomy closure operation,the distal bowel stenosis,the recurrence of the tumor,unhealed injury and the underlying disease should be excluded and controlled,and the closure operation can be given after 3-6 months of colostomy operation.%目的:探讨肠造口还纳手术时机、手术方式及并发症发生的预防、处理。方法回顾性分析137例肠造口还纳手术的患者,统计分析其造口原因、造口方法、还纳时间、术后并发症及预防处理方法等。结果造口原因包括低位直肠癌低位吻合近侧保护性造口57例,结直肠损伤63例,吻合口漏9例,克罗恩病、家族性息肉病等8例;还纳平均时间162.3 d;术前检查肠镜117例,钡剂灌肠20例;吻合器吻合122

  20. Influence of barium substitution on bioactivity, thermal and physico-mechanical properties of bioactive glass

    Energy Technology Data Exchange (ETDEWEB)

    Arepalli, Sampath Kumar, E-mail: askumar.rs.cer11@iitbhu.ac.in; Tripathi, Himanshu; Vyas, Vikash Kumar; Jain, Shubham; Suman, Shyam Kumar; Pyare, Ram; Singh, S.P., E-mail: spsinghceram@gmail.com

    2015-04-01

    Barium with low concentration in the glasses acts as a muscle stimulant and is found in human teeth. We have made a primary study by substituting barium in the bioactive glass. The chemical composition containing (46.1 − X) SiO{sub 2−}–24.3 Na{sub 2}O–26.9 CaO–2.6 P{sub 2}O{sub 5}, where X = 0, 0.4, 0.8, 1.2 and 1.6 mol% of BaO was chosen and melted in an electric furnace at 1400 ± 5 °C. The glasses were characterized to determine their use in biomedical applications. The nucleation and crystallization regimes were determined by DTA and the controlled crystallization was carried out by suitable heat treatment. The crystalline phase formed was identified by using XRD technique. Bioactivity of these glasses was assessed by immersion in simulated body fluid (SBF) for various time periods. The formation of hydroxy carbonate apatite (HCA) layer was identified by FTIR spectrometry, scanning electron microscope (SEM) and XRD which showed the presence of HCA as the main phase in all tested bioactive glass samples. Flexural strength and densities of bioactive glasses have been measured and found to increase with increasing the barium content. The human blood compatibility of the samples was evaluated and found to be pertinent. - Highlights: • In vitro bioactivity of soda-lime–baria-phospho-silicate glass was investigated. • HCA formed on surface of glasses was confirmed by XRD, SEM and FTIR spectrometry. • Mechanical properties of glasses were found to increase with barium addition. • Hemolysis showed that 1.2 mol% BaO bioactive glass exhibited better biocompatibility. • Barium substituted bioactive glasses can be used as bone implants.

  1. A study of the microchemistry of nanocrystalline barium titanate with tetragonal and pseudocubic room temperature symmetries

    Science.gov (United States)

    Lacey, Robert A.

    The investigation of possible effects of undesired surface species on barium titanate, one of the most utilized ferroelectric ceramics, constitutes the focus of this work. Six commercial barium titanate powders from three manufacturers representing two different synthesis processes, with average particle sizes from 40 nm to 470 nm, were analyzed in this study. Four of the nanopowders exhibited pseudocubic room temperature symmetry. Diffuse Reflectance Infrared Fourier Transform (DRIFT) spectroscopic analysis of the nanopowders was conducted in ambient atmosphere at room temperature. High temperature DRIFT followed incorporating four avenues of analysis: moisture adsorption studies, deuterium oxide exchange studies, carbon dioxide adsorption studies, and high temperature analysis under dry air and UHP nitrogen atmospheres. At the highest temperature used in this study, 1173K, moisture and the accompanying incorporated protonic impurities were still present. The powders readily readsorbed moisture during rapid cooling, 170K/minute, to room temperature. The smallest powder, as received, formed spherical agglomerates up to 10 mum diameter. These sintered as separate units attaining diameters up to 60 mum during intermediate stage sintering. X-ray photoelectron spectroscopy indicated a surface contamination layer of 10 A to 18 A; 50--70% of which was barium carbonate, the balance being atmospheric adsorbed species. Samples cooled at 3K/minute after an 1173K calcine retained cubic symmetry as indicated with high temperature X-ray diffraction. However, spectral evidence was obtained indicating that upon the rapid cooling from the 1173K calcine, a reorientation to the room temperature tetragonal symmetry was observed. Further, SEM and TEM supported this finding with visual evidence of interfacial rearrangement including corroborating electron diffraction analysis. This data, therefore, substantiated the hypothesis that the cause of the room temperature pseudocubic

  2. AFM studies of swift heavy ion and electron irradiated mixed barium strontium borate nonlinear optical crystal

    International Nuclear Information System (INIS)

    Single crystals of novel nonlinear optical material of mixed barium strontium borate is grown in our laboratory by employing the low-temperature solution technique. Equal proportion (1:1 molar ratio) of AR grade barium borate and strontium borate are mixed together in double distilled water to prepare a supersaturated solution. The solution is allowed to evaporate at constant temperature (30 deg. C) in a Petri dish for about a week which resulted in the formation of seed crystals. These seed crystals are used to grow larger crystals by suspending them using fine silk thread in the supersaturated mother solution. The solution is allowed to evaporate at constant temperature. This resulted in the growth of good transparent crystals of dimension 15 mmx10 mmx1 mm after about one month. These crystals show good second harmonic generation (SHG) efficiency. The mixed barium strontium borate crystal is found to be a promising nonlinear optical crystal, which possibly can be used for fabrication of photonic devices. The single crystals of mixed barium strontium borate are irradiated by 120 MeV Ag+13 swift heavy ions (SHI) of fluence 5x1011 ions/cm2 at Nuclear Science Centre, New Delhi and also by electrons of 8 MeV energy with a fluence 5.7x109/cm2 using Microtron accelerator at Mangalore University. Surface morphology studies of these crystals are carried out using atomic force microscope. The AFM topographical images of these SHI/electron irradiated single crystals of mixed barium strontium borate are obtained from different frames of the sample taken at different magnifications using atomic force microscope. An attempt is made to explain the surface damage caused due to SHI/electron irradiation using the observed AFM images

  3. THERMAL DECOMPOSITION MECHANISM OF BARIUM BENZOATE%苯甲酸钡的热分解机理

    Institute of Scientific and Technical Information of China (English)

    张克立; 袁继兵; 袁良杰; 孙聚堂

    1999-01-01

    Barium benzoate was synthesized in semi-solid phase reaction. The complex was characterized by elemental analysis, IR, X-ray powder diffraction. It is layered structure, monoclinic system. The mechanism of thermal decomposition for barium benzoate was studied by using TG, DTA, IR and gas chromatography-mass spectrometer. The thermal decompositon of barium benzoate in nitrogen proceeded in one stage: it decomposed to form BaCO3 and organic compounds. The organic compounds obtained from decomposition reaction are mainly benzophenone, triphenylmethane and so on.

  4. CT colonography: optimisation, diagnostic performance and patient acceptability of reduced-laxative regimens using barium-based faecal tagging

    OpenAIRE

    Stuart A Taylor; Slater, Andrew; Burling, David N.; Tam, Emily; Greenhalgh, Rebecca; Gartner, Louise; Scarth, Julia; Pearce, Robert; Bassett, Paul; Halligan, Steve

    2007-01-01

    To establish the optimum barium-based reduced-laxative tagging regimen prior to CT colonography (CTC). Ninety-five subjects underwent reduced-laxative (13 g senna/18 g magnesium citrate) CTC prior to same-day colonoscopy and were randomised to one of four tagging regimens using 20 ml 40%w/v barium sulphate: regimen A: four doses, B: three doses, C: three doses plus 220 ml 2.1% barium sulphate, or D: three doses plus 15 ml diatriazoate megluamine. Patient experience was assessed immediately af...

  5. Modelling turnover of Cs-137 in two subarctic salmonid ecosystems

    International Nuclear Information System (INIS)

    The turnover of cesium-137 was simulated in two categories of subarctic, alpine lake ecosystems - a natural lake with Gammarus lacustris as major fish prey and a lake reservoir with introduced Mysis relicta as a new fish-food organism. The resulting concentrations of Cs-137 in two salmonid species - Arctic char (Salvelinus alpinus) and brown trout (Salmo trutta) - were calculated using a multi-compartment model. Observed data were taken from a major case study evaluating the distribution, pathways and major transport mechanisms of Chernobyl cesium through northern lake ecosystems in 1986-90. The aim of this study was to design a specific conceptual model for calculation of the levels of Cs-137 in fish from simple lake ecosystems, which could be adopted for other more complex types of lakes. A multi-compartment model of the ecosystem was designed and the equations were solved with the BIOPATH-code. The uncertainty of the results due to the uncertainty of input values was examined using the PRISM-system. The model gave good correlations to measured data for Cs-137 in water, zooplankton, macro invertebrates and fish in both lakes. The predicted levels in sediments were, however, considerably lower than the observed values. The inflow of Cs-137 from the drainage area to the two lakes was identified as the main contributor to the uncertainty of the long-term prognoses. 33 refs, 6 figs, 3 tabs

  6. Distribution of fallout cesium-137 in the Chesapeake Bay

    International Nuclear Information System (INIS)

    A technique was developed for simple analysis of 137Cs concentrations in water, sediments, and biota in the fractional picocurie per liter range. These measurements are important, since fallout 137Cs will be present in estuarine environments for a generation. The concentration of 137Cs in water is important to studies of distribution coefficients, or concentration factors between water and sediment or organisms. Fallout 137Cs is also a natural tracer, making possible experiments on a span of space and time that is impossible with intentionally added tracers. Thus, one can determine an approximate residence time for a body of brackish water with a few 137Cs concentration measurements, given the average depth and typical fallout deposition rate. This estimate is good enough for first estimates as to the capacity of the body of water for various pollutants. Measurements at several sites, and at all seasonal conditions, can be used to solve the mass and concentration balance equations that more rigorously describe the hydrography of the estuary. (U.S.)

  7. Sorption of 137Cs from Aqueous Waste Solutions using Pottery

    International Nuclear Information System (INIS)

    A simple and inexpensive method for sorption of 137Cs from aqueous solutions using a highly available vase shape pottery material has been investigated. Porosity of the used pottery allowed for the penetration of the radioactive solution through its permeable body. Two routes had been investigated for cesium removal from the radioactive solutions. In the first one, pottery bodies were immersed into the radioactive solutions. In the second method; the radioactive solutions were filled the inner volumes of the pottery bodies. Vase shape pottery showed higher sorption capability for 137Cs much more than its powder forms, especially in the alkaline medium. Pottery bodies showed high potential for 137Cs removal. Adsorption isotherms revealed good lit to the Freundlich and Langumir isotherms. During sorption processes outside and inside the pottery body, 137Cs was well captured inside the amorphous microstructure of the pottery body. In this respect, micro filtration of cesium radionuclides through the used pottery could be postulated. Desorption experiments indicated higher immobilization affinity for radiocesium into pottery bodies, which indicates a high containment for 137Cs with an irreversible fixation mechanism

  8. Multicomponent doped barium strontium titanate thin films for tunable microwave applications

    Science.gov (United States)

    Alema, Fikadu Legesse

    In recent years there has been enormous progress in the development of barium strontium titanate (BST) films for tunable microwave applications. However, the properties of BST films still remain inferior compared to bulk materials, limiting their use for microwave technology. Understanding the film/substrate mismatch, microstructure, and stoichiometry of BST films and finding the necessary remedies are vital. In this work, BST films were deposited via radio frequency magnetron sputtering method and characterized both analytically and electrically with the aim of optimizing their properties. The stoichiometry, crystal structure, and phase purity of the films were studied by varying the oxygen partial pressure (OPP) and total gas pressure (TGP) in the chamber. A better stoichiometric match between film and target was achieved when the TGP is high (> 30 mTorr). However, the O2/Ar ratio should be adjusted as exceeding a threshold of 2 mTorr in OPP facilitates the formation of secondary phases. The growth of crystalline film on platinized substrates was achieved only with a lower temperature grown buffer layer, which acts as a seed layer by crystallizing when the temperature increases. Concurrent Mg/Nb doping has significantly improved the properties of BST thin films. The doped film has shown an average tunability of 53%, which is only ˜8 % lower than the value for the undoped film. This drop is associated with the Mg ions whose detrimental effects are partially compensated by Nb ions. Conversely, the doping has reduced the dielectric loss by ˜40 % leading to a higher figure of merit. Moreover, the two dopants ensure a charge neutrality condition which resulted in significant leakage current reduction. The presence of large amounts of empty shallow traps related to Nb Ti localize the free carriers injected from the contacts; thus increase the device control voltage substantially (>10 V). A combinatorial thin film synthesis method based on co-sputtering of two BST

  9. Radiochemical determination of {sup 137}Cs in foods

    Energy Technology Data Exchange (ETDEWEB)

    Kastner, Geraldo F.; Ferreira, Andrea Vidal; Monteiro, Roberto P.G., E-mail: gfk@cdtn.br, E-mail: avf@cdtn.br, E-mail: rpgm@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    A determination of radionuclides in food samples is important in commodities in order to attend to regulatory requirements for international trade. As a long-lived radioisotope of cesium, {sup 137}Cs is produced as a result of human nuclear activities and than its contamination level evaluation among others radionuclides in foods is necessary. A methodology for the determination of {sup 137}Cs in foods, pork and fish, is described. The procedures covered homogenization and freeze-drying of the samples. The {sup 137}Cs was measured by gamma spectrometry using Canberra 50% HPGe detector. The counting was carried out with Monte Carlo software for detection conditions optimization including geometry and chemical data information. A certified sample, SRM IAEA-375, was analyzed in order to evaluate the reliability of the method, and the results showed good agreement between the measured and certified values. (author)

  10. The forecast of agricultural crop production contamination by Cs 137

    International Nuclear Information System (INIS)

    The saved up experimental data on the influence of various factors on radionuclides transition in plants allows predicting their contents in production of agricultural crops. It is established, that receipt radionuclides in plants depends on a kind and a grade of cultivated cultures, types of ground, granulometric structure, parameters of soil fertility, humidifying grounds, levels of application of mineral fertilizers and other factors. The determining factor on Cs 137 receipt in plants is presented in ground exchange potassium. The forecast of Cs 137 transition from ground in plants is widely used in an agricultural production at planning and realization of a complex of protective actions. According to predicted levels of Cs 137 accumulation in production the directions of its use are determined. (authors)

  11. Dating of mine waste in lacustrine sediments using cesium-137

    Science.gov (United States)

    Rember, W. C.; Erdman, T. W.; Hoffmann, M. L.; Chamberlain, V. E.; Sprenke, K. F.

    1993-11-01

    For over a century Medicine Lake in northern Idaho has received heavy-metal-laden tailings from the Coeur d'Alene mining district. Establishing the depositional chronology of the lake bottom sediments provides information on the source and rate of deposition of the tailings. Cesium-137, an isotope produced in the atmosphere by nuclear bomb tests, was virtually absent in the environment prior to 1951, but reached its apex in 1964. Our analysis of cesium-137 in the sediments of Medicine Lake revealed that 14 cm of fine-grained tailings were deposited in the lake from 1951 to 1964 and tailing deposition downstream was greatly reduced by the installation of tailings dams in the district in 1968. Cesium-137 analysis is accomplished by a fairly simple gamma-ray counting technique and should be a valuable tool for analyzing sedimentation in any lacustrine environment that was active during the 1950s and 1960s.

  12. Transfer of 137Cs into fish in small forest lakes

    International Nuclear Information System (INIS)

    The transfer of 137Cs into fish in seepage and drainage lakes from 1988 to 1992 was analysed using linear regression. Empirical results for 137Cs in lake water and fish were used to calculate concentration factors (CFs). In the drainage lakes the CF decreased during the study period by 9% per year whereas in the seepage lakes the CF increased significantly by 4.3% per year. The transfer of 137Cs into pike was significantly (1.6 times) higher than that into perch. The CF increased on average by 3.4% for each 1-cm increase in the median size of perch. The relationship between the water chemistry and the CF differed between clear-water seepage and brown-water drainage lakes.

  13. Cesium 137 in oils and plants from Guatemala

    International Nuclear Information System (INIS)

    Since 1990 the project of radioactive and environmental contamination started in Guatemala. Studies about the radioactive contamination levels are made within the framework of this project. Cesium-137 has been an interest radionuclide, because it is a fission product released to the environment by the use of nuclear weapons and nuclear power plants accidents. The sampling consisted in collection of soil and grass in 20 provinces of Guatemala, one point by province, and it was made in 1990. The cesium-137 concentration in the samples, was determined by gamma spectrometry, using an hyper pure germanium detector. The results show the presence of radioactive contamination in soil and grass due to cesium-137, at levels that might be considered as normal. The levels found are not harmful for human health, and its importance is the fact that can be used as reference levels for the environmental radioactivity monitoring in Guatemala

  14. Household methods to reduce {sup 137}Cs contents of mushrooms

    Energy Technology Data Exchange (ETDEWEB)

    Kostiainen, E. [Radiation and Nuclear Safety Authority - STUK, Helsinki (Finland)

    2005-09-15

    High radiocaesium contents in different species of mushrooms have been observed in areas contaminated by radiocaesium deposition after the Chernobyl accident in 1986. There has been no significant reduction in the {sup 137}Cs contents of mushrooms during the past ten years, besides via radioactive decay. The internal radiation dose received via mushrooms can be reduced by processing mushrooms before consumption. Various household methods were studied to find out their efficiency to reduce {sup 137}Cs contents of mushrooms. The methods tested were the same as normally used in cooking. The tests were made for the species of edible mushrooms widely consumed. The retention factors for the treatments tested were in most cases 0.2-0.3. The efficiency of treatments in reducing the {sup 137}Cs contents increased with larger water volumes and prolonged treatment times.

  15. Cesium-137 in soil texture fractions and its impact on Cesium-137 soil-to-plant transfer

    International Nuclear Information System (INIS)

    Field studies at two sites contaminated by the Chernobyl fallout showed 137Cesium (Cs) soil-to-plant transfer factors in wheat, rye and potato. Transfer values ranged from 0.0017 (potato tuber) to 0.07 (wheat straw). Generally transfer coefficients in cereal grains and potato tubers were significantly below the values of the shoots. A comparison of the two sites led to the conclusion that for all plants investigated 137Cs transfer factors were higher in Lower Austria (Calcic Chernozem) than in Upper Austria (Eutric Cambisol). The specific activities of the texture fractions of the two soil types increased from sand to silt and clay. In the Calcic Chernozem the ratio of the 137Cs activity in the silt fraction to the total activity in the soil was considerably higher than in the Eutric Cambisol. At the same time extractability of 137Cs from the silt fraction of the latter soil was clearly lower. Both results mainly were attributed to the differences between the soils according to the organic matter content of the silt fractions, the Calcic Chernozem being seven times higher. Therefore, the differences in the 137Cs-soil-to-plant transfer can be attributed partly to these soil characteristics. (authors)

  16. Uptake and transfer factors of 137Cs by mushrooms

    International Nuclear Information System (INIS)

    The 137Cs content of 118 species (668 samples) of higher fungi collected in the period from August 1984 to October 1989 at three different locations in Styria, Austria, was determined by gamma-spectrometry. The Cs-content of most mushrooms has been increasing since September 1986. In order to find out which factors determine the 137Cs-contamination of mushrooms and the transfer-value soil to mushroom, the concentration of total and plant-available radiocesium in soils as well as the pH-value, the content of humus, clay, silt, sand, exchangeable cations, the composition of the clay minerals, and the particle size distribution of the soils of two different locations were examined. The higher the 137Cs contamination of the soil, the thicker the layer of humus and the higher the content of humus, the lower the pH-value, and the lower the amount of essential cations, especially of K+, the higher the amount of 137Cs plant-available will be. Therefore, the contamination of the mushrooms in the coniferous forest of Koralpenblick (1000 m) is higher than in the mixed forest at the Rosenberg around Graz at approx. 500 m height. Of 26 different species of mushrooms measured at both sites, only 61% show the highest TF-values soil to mushrooms also at the Koralpenblick. In the spruce forest at Koralpenblick there are many species of mushrooms with high 137Cs-contamination which were not found at the Rosenberg. However, the properties of the species to which a mushroom belongs are more important than environmental conditions and soil properties. The transfer values of 40K stay within narrow bounds, whereas those of 137Cs differ widely. (orig.)

  17. Effects of barium on the nonlinear electrical characteristics and dielectric properties of SnO2-based varistors

    Institute of Scientific and Technical Information of China (English)

    Wang Chun-Ming; Wang Jin-Feng; Wang Chun-Lei; Chen Hong-Cun; Su Wen-Bin; Zang Guo-Zhong; Qi Peng; Zhao Ming-Lei; Ming Bao-Quan

    2004-01-01

    The effects of barium on electrical and dielectric properties of the SnO2·Co2Oa.Ta2O5 varistor system sintered at 1250℃ for 60min were investigated. It is found that barium significantly improves the nonlinear properties. The breakdown electrical field increases from 378.0 to 2834.5V/mm, relative dielectric constant (at 1kHz) falls from 1206 to 161 and the resistivity (at 1kHz) rises from 60.3 to 1146.5kΩ·cm with an increase of BaCO3 concentration from 0mol%to 1.00mol%. The sample with 1.00mol% barium has the best nonlinear electrical property and the highest nonlinear coefficient (α=29.2). A modified defect barrier model is introduced to illustrate the grain-boundary barrier formation of barium-doped SnO2-based varistors.

  18. The behaviour of 137Cs in the aquatic environment

    International Nuclear Information System (INIS)

    Through 137Cs concentration profiles in sediments from Rochedo Reservoir, it was possible to estimate the amount of this radionuclide (94 TBq) which has reached the Meia Ponte River system, as a consequence of the Goiania Radiological accident in 1987. Based on in-situ measurements as well as on laboratory studies, the influence of NH4+ concentration on the Kd value was also investigated. The results have shown that for high NH4d+ concentrations there is a clear correlation between both parameters. It was also observed the influence on the ageing effect on the 137Cs release from the sediment, as well as of the illite content on it. (author)

  19. Determination of Cs-134 and Cs-137 rain water samples

    International Nuclear Information System (INIS)

    In order to setting an environmental monitoring program at IPEN, was developed a fast and simple methodology for concentration of Cs-134 and Cs-137 in rain water. This procedure consists in the precipitation of cesium and others cathions of its family (NH4+, K+ and Rb+) by ammonium molybdophosphate. The measures of the desintegration rates of Cs-134 and Cs-137 was done by gamma spectrometry in a Ge(Li) detector. After setting up the ideal experimental conditions, the procedure was used to analyze four samples of rain water. (author)

  20. Transport processes of Cs-137 in lake environments

    Energy Technology Data Exchange (ETDEWEB)

    Hilton, J.; Carrick, T.R.; Lishman, J.P.; Rigg, E. [Inst. of Freshwater Ecology, Windermere (United Kingdom); Davison, W.; Kelly, M.; Hamilton-Taylor, J. [Lancaster Univ. (United Kingdom). Inst. of Environmental and Biological Sciences

    1992-12-31

    Radiocesium levels in the waters of the Lake District dropped after the initial deposition following the Chernobyl reactor accident. However they continued to be measurable several years after the event. Caesium 137 concentrations were measured in the sediments of Esthwaite water and Windermere to determine the input of caesium 137 from the catchment area to the lakes. Experiments were conducted to ascertain the chemical conditions such as pH value, adsorption, competing ions which might contribute to maintaining caesium levels in the lakes. (U.K.).

  1. Declassification of 137Cs liquid wastes by reverse osmosis

    International Nuclear Information System (INIS)

    In June 1998, a 137Cs source was accidentally melted in one of the furnaces of a stainless steel production company located in Spain. As a result of this incident, the furnace and its cooling circuit were radioactively contaminated. LAINSA (Logistica y Acondicionamientos Industriales S.A.) company took charge of the plant decontamination process, in which 40 m3, approximately, of 137Cs contaminated water with a mean activity of 300 kBq/L were generated. This company contacted the Chemical and Nuclear Engineering Department of the Polytechnic University of Valencia (UPV) to develop a project for radioactive liquid wastes treatment

  2. The utilization of caesium 137 in studying soil degradation

    International Nuclear Information System (INIS)

    The caesium 137 isotope is distributed in the atmosphere during nuclear explosions, and is absorbed in the upper horizons of the soil on reaching the ground. When it is incorporated in the fine fraction of the soil, caesium 137 measurement allows movements affecting cultivated lands (mass movements, runoff effects, wind action) and rate of soil degradation over half a century to be evaluated. Vegetal cover and techniques of soil utilization must be considered; this method has been tested on a watershed in the Parisian Basin. 5 figs., 26 refs

  3. Transport processes of Cs-137 in lake environments

    International Nuclear Information System (INIS)

    Radiocesium levels in the waters of the Lake District dropped after the initial deposition following the Chernobyl reactor accident. However they continued to be measurable several years after the event. Caesium 137 concentrations were measured in the sediments of Esthwaite water and Windermere to determine the input of caesium 137 from the catchment area to the lakes. Experiments were conducted to ascertain the chemical conditions such as pH value, adsorption, competing ions which might contribute to maintaining caesium levels in the lakes. (U.K.)

  4. Dosimetry of a Cesium 137 source; Dosimetria de una fuente de Cesio 137

    Energy Technology Data Exchange (ETDEWEB)

    Torres R, J.G.; Manzanares A, E.; Vega C, H.R. [Unidades Academicas de Estudios Nucleares, Universidad de Zacatecas (Mexico)

    2005-07-01

    It was carried out a dosimetric study of a source of Cesium 137 used in investigations of Radiobiology. This radionuclide has a half life of 30.07 years and it emits photons of 661.657 keV with a probability of 85.2%. The source has been used in a series of experiments trending to observe the cellular response before the gamma rays, as well as for the calibration of equipment of radiological protection. For such reason it is important to determine the dosimetric properties. In this work it was determined the absorbed dose that this source takes when being placed in the center from a methylmethacrylate badge to three distances, 5, 10 and 15 cm. The dose was measured with thermoluminescent dosemeters and it was calculated by means of Monte Carlo method, also was derived an expression that allows to determine the dose starting from the information of the activity of the source and of the distance regarding the same one. (Author)

  5. Enhanced sintering and conductivity study of cobalt or nickel doped solid solution of barium cerate and zirconate

    DEFF Research Database (Denmark)

    Ricote, Sandrine; Bonanos, Nikolaos

    2010-01-01

    atmospheres and compared to the undoped compounds. The ionic and p-type conductivities have been determined, as well as the activation energy in wet reducing atmospheres, in which protonic conduction is dominant. A decrease of the ionic conductivity is noticeable for the cobalt or nickel doped barium...... zirconate (x = 0), while not for cobalt or nickel solid solution of barium cerate and zirconate (x = 0.2)....

  6. 134Cs: 137Cs and 106Ru: 137Cs ratios in intertidal sediments from the Cumbria and Lancashire coasts England

    Science.gov (United States)

    Stanners, D. A.; Aston, S. R.

    1981-10-01

    The distributions of 134Cs, 137Cs and 106Ru in intertidal surface sediments from the coasts of Cumbria and Lancashire, north-west England, are reported. The ratios of 134Cs: 137Cs and 106Ru: 137Cs activities have been used together with the isotopic composition of the Windscale radioactive effluents to examine the contamination history of sediments. Distinct differences between the activities and time of contamination of muds, silts and sands are found, and the apparent lag times of transport of radioactive wastes to different sediment localities are estimated. The relatively high activities in fine sediments reflect recent discharges indicating a rapid response to discharge, while the sands contain low levels of older contamination. Apparent lag times of up to 6 years are estimated for the study area; the transport to the south is generally more rapid than to the north. These results have consequences for the operation and interpretation of radiological monitoring in coastal areas.

  7. Intra-individual comparison of patient acceptability of multidetector-row CT colonography and double-contrast barium enema

    International Nuclear Information System (INIS)

    AIMS: To compare the subjective acceptability of CT colonography in comparison with barium enema in older symptomatic patients, and to ascertain preferences for future colonic investigation. MATERIALS AND METHODS: The study population comprised 78 persons aged 60 years or over with symptoms suggestive of colorectal neoplasia, who underwent CT colonography followed the same day by barium enema. A 25-point questionnaire was administered after each procedure and an additional follow-up questionnaire a week later. Responses were compared using Wilcoxon matched pairs testing, Mann-Whitney test statistics and binomial exact testing. RESULTS: Participants suffered less physical discomfort during CT colonography (p=0.03) and overall satisfaction was greater compared with barium enema (p=0.03). On follow-up, respondents reported significantly better tolerance of CT colonography (p=0.002), and were less prepared to undergo barium enema again (p<0.001). Of 52 subjects expressing an opinion, all preferred CT to barium enema. CONCLUSION: Patient satisfaction was higher with CT colonography than barium enema. CT colonography caused significantly less physical discomfort and was overwhelmingly preferred by patients

  8. Site-selective spectroscopy of the solid-state defect chemistry in erbium-doped barium titanate.

    Science.gov (United States)

    Bak, John D; Wright, John C

    2005-10-01

    Erbium-doped barium titanate crystals were studied by laser-induced fluorescence spectroscopy. Thirteen spectroscopically distinct erbium ion sites were found. The relative concentrations of the different sites changed as a function of the crystal and its preparation and treatment. One major site was present in all crystals. The site distribution was changed either by growing codoped crystals with donor (La3+) and acceptor (Sc3+) ions or by changing the temperature and partial pressure of the oxygen in the annealing atmosphere. Equilibrium calculations were done to simulate the defect distributions that result from the charge compensation of the erbium ions. Comparison with the observed dependence of the site spectral intensities indicated that the erbium enters the lattice on barium sites. We assigned the dominant site to an erbium ion on a barium site that is locally compensated by a barium vacancy, whereas the other lower-intensity sites corresponded to erbium ions that are locally compensated by an electron and a more complex center of an erbium, a barium vacancy, and a hole. The spectra of one sample showed that its defects were different and were characteristic of a sample that had not equilibrated. The new sites in this sample were assigned to erbium entering the lattice on a titanium site, which was then locally compensated by an oxygen vacancy or a hole. Heating equilibrated the sample and changed the erbium to a barium site. PMID:16853368

  9. Use of Different Barium Salts to Inhibit the Thaumasite Form of Sulfate Attack in Cement-based Materials

    Institute of Scientific and Technical Information of China (English)

    SU Ying; WEI Xiaochao; HUANG Jian; WANG Yingbin; HE Xingyang; WANG Xiongjue; MA Baoguo

    2016-01-01

    We investigated the effects of different barium compounds on the thaumasite form of sulphate attack (TSA) resistance of cement-based materials when they were used as admixtures in mortars. Moreover, we analyzed the inhibition mechanisms within different types of barium salts, namely BaCO3 and Ba(OH)2, on the thaumasite formation. The control cement mortar and mortars with barium salts to cement and limestone weight ratios of 0.5%, 1.0%, and 1.5% were immersed in 5% (by weight) MgSO4 solution at 5℃ to mimic TSA. Appearance, mass, and compressive strength of the mortar samples were monitored and measured to assess the general degradation extent of these samples. The products of sulphate attack were further analyzed by XRD, FTIR, and SEM, respectively. Experimental results show that different degradation extent is evident in all mortars cured in MgSO4 solution. However, barium salts can greatly inhibit such degradation. Barium in hydroxide form has better effectiveness in protection against TSA than carbonate form, which may be due to their solubility difference in alkaline cement pore solution, and the presence of these barium compounds can reduce the degree of TSA by comparison with the almost completely decomposed control samples.

  10. Study on the preparation and formation mechanism of barium sulphate nanoparticles modified by different organic acids

    Indian Academy of Sciences (India)

    Yuhua Shen; Chuanhao Li; Xuemei Zhu; Anjian Xie; Lingguang Qiu; Jinmiao Zhu

    2007-07-01

    This paper reports a simple method to prepare barium sulphate nanoparticles by use of tetradecanoic acid, hexadecanoic acid and stearic acid as modifier. The barium sulphate nanoparticles obtained are characterized by using Fourier transform infra-red spectroscopy (FT-IR), powder X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic laser light scatter (DLLS) and thermogravimetric analysis (TGA), respectively. The results show that the BaSO4 particles are all spherical and in the nano-scale. Our method has a better dispersion and controllable diameter dependent on the length of the chain of organic acid and the pH value of the system. A possible mechanism is also discussed.

  11. Barium enema carried out by digital luminescent radiography (DLR) and conventional screen-film system combinations

    International Nuclear Information System (INIS)

    120 double-contrast barium enemas were obtained by both digital luminescent radiography (DLR) and conventional screen-film systems, the digital exposure dose being 50% of the conventional one. In DLR two differently post processed images were obtained from one X-ray exposure: a display with low spatial frequency enhancement was processed to look like a conventional radiograph and was complemented by a display with high spatial frequency enhancement. Analysing the results statistically DLR proved to be diagnostically equivalent to conventional radiography despite the reduction in exposure dose and a slightly diminished image quality. High spatial frequency enhancement did not provide further diagnostic information and is therefore superfluous in barium enemas. (orig.)

  12. Elastic properties investigation of gamma-radiated barium lead borosilicate glass using ultrasonic technique

    International Nuclear Information System (INIS)

    Highlights: → Change in acoustical parameter due to composition effect and irradiation effect. → Changes in the structure of the glass (BO3 → BO4) due to the effect of radiation. → Structural changes in the BO3 to BO4 have a more compactness structure. - Abstract: The ultrasonic velocities were measured in barium lead borosilicate glass samples of different compositions before and after irradiation with γ-rays. Measurements were carried out at room temperature and 4 MHz frequency using ultrasonic technique. The ultrasonic velocities data of glass samples have been used to find the elastic modulus and micro-hardness. Densities of glass samples were measured by Archimedes's principle using n-hexane as immersion liquid. It was found that ultrasonic velocity, elastic modulus and micro-hardness increase with increasing barium oxide content and increasing γ-radiation dose.

  13. Synthesis and Fluorescence of Europium-Doped Barium Fluoride Cubic Nanocolumns

    Institute of Scientific and Technical Information of China (English)

    连洪州; 刘洁; 叶泽人; 石春山

    2004-01-01

    Europium-doped barium fluoride cubic nanocolumns were synthesized from the quaternary water in oil reverse microemulsions. In this process, the aqueous cores of water/cetyl trimethyl ammonium bromide(CTAB)/n-butanol/n-octane reverse microemulsions were used as microreactors for the precipitation of europium doped barium fluoride. XRD analysis shows that under the dopant concentration of 0.06%(molar fraction), the products are single phase. The result products are cubic column-like with about 30~50 nm edge length of cross section, and about 200 nm of length obtained from the transmission electron microscopy(TEM), and atomic force microscopy(AFM). Under the 0.06%(molar fraction) of dopant concentration, the fluorescence of Eu2+ and Eu3+ under the 589 of excitation wavelength is observed.

  14. Barium phosphate conversion coating on die-cast AZ91D magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Poor corrosion resistance limits the application of magnesium alloys.Conversion coating is widely used to protect magnesium alloys because of easy operation and low cost.A novel conversion coating on die.cast AZ91D magnesium alloy containing barium salts was studied.The optimum concentrations of Ba(NO3)2,Mn(NO3)2 and NH4H2PO4 are 25 g/L,15 mL/L and 20 g/L,respectively,based on orthogonal test resulm.The treating time,solution temperature and PH value are settled to be 5-30 min,50-70℃and 2.35-3.0.respectively.The corrosion resistance of barium conversion coating is better than that of manganese-based phosphate conversion coating by immersion test.The coating is composed of Ba,P, O,Mg,Zn,Mn and Al by EDX analysis.

  15. Absolute Te$_2$ reference for barium ion at $455.4~$nm

    CERN Document Server

    Dutta, T; Mukherjee, M

    2016-01-01

    Precision atomic spectroscopy is presently the work horse in quantum information technology, metrology, trace analysis and even for fundamental tests in physics. Stable lasers are inherent part of precision spectroscopy which in turn requires absolute wavelength markers suitably placed corresponding to the atomic species being probed. Here we present, new lines of tellurium (Te$_2$) which allows locking of external cavity diode laser (ECDL) for precision spectroscopy of singly charged barium ions. In addition, we have developed an ECDL with over 100 GHz mod-hop-free tuning range using commercially available diode from $\\textit{Nichia}$. These two developments allow nearly drift-free operation of a barium ion trap set-up with one single reference cell thereby reducing the complexity of the experiment.

  16. Efficient photoionization for barium ion trapping using a dipole-allowed resonant two-photon transition

    CERN Document Server

    Leschhorn, G; Schaetz, T

    2011-01-01

    Two efficient and isotope-selective resonant two-photon ionization techniques for loading barium ions into radio-frequency (RF)-traps are demonstrated. The scheme of using a strong dipole-allowed transition at \\lambda=553 nm as a first step towards ionization is compared to the established technique of using a weak intercombination line (\\lambda=413 nm). An increase of two orders of magnitude in the ionization efficiency is found favoring the transition at 553 nm. This technique can be implemented using commercial all-solid-state laser systems and is expected to be advantageous compared to other narrowband photoionization schemes of barium in cases where highest efficiency and isotope-selectivity are required.

  17. Scaled-energy spectroscopy of a |M|=1 Rydberg barium atom in an electric field

    Institute of Scientific and Technical Information of China (English)

    Wang Lei; Quan Wei; Shen Li; Yang Hai-Feng; Shi Ting-Yun; Liu Xiao-Jun; Liu Hong-Ping; Zhan Ming-Sheng

    2009-01-01

    We observe strong energy-dependent quantum defects in the scaled-energy Stark spectra for |M|=1 Rydberg states of barium atoms at three scaled energies: ε= -2.000, ε= -2.500 and ε=-3.000. In an attempt to explain the observations, theoretical calculations of closed orbit theory based on a model potential including core effect are performed for non-hydrogenic atoms. While such a potential has been uniformly successful for alkali atoms with a single valence electron, it fails to match experimental results for barium atoms in the 6snp Rydberg states with two valence electrons. Our study points out that this discrepancy is due to the strong perturbation from the 5d8p state, which voids the simple approximation for constant quantum defects of principle quantum number n.

  18. Laser plasma channel formation in barium vapor based on superelastic heating of electrons

    International Nuclear Information System (INIS)

    Computational study of plasma channel formation kinetics in optically dense barium vapor irradiated by pulsed laser light tuned to the Ba I resonance transition at λ = 553.5 nm has been performed. Seed electrons are produced due to the mechanism of atoms associative ionization, which then gain energy in superelastic collisions and initiate the avalanche ionization of atoms by electron impact. We have studied the influence of radiative transfer effects in cylindrically symmetric gas volume on the excitation kinetics of multilevel barium atoms, dynamics of absorption of laser radiation, and the plasma channel expansion in the form of a halo in condition of competition between the ionizing and quenching electron collisions with excited atoms. (paper)

  19. Effect of CaF2 addition on optical properties of barium phosphate glasses

    Science.gov (United States)

    Kumar, N. Manoj; Rao, G. Venkateswara; Akhila, B. E.; Shashikala, H. D.

    2014-04-01

    Ternary barium phosphate glasses, (50-X)BaO-XCaF2-50P2O5 have been prepared by adding 0-10 mol% of CaF2 to binary barium phosphate glasses. The amorphous nature of the prepared glasses was confirmed by X-ray diffraction technique. The UV-Visible absorption spectra have been recorded, optical band gap energy Eopt and Urbach energy Etail were determined. Shift in Eopt and Etail with increase in concentration of CaF2 is noted. FTIR analysis was carried out to investigate the short and intermediate-range orders in glasses. Shift of (P-O-P) band to higher wave number with the substitution of BaO with CaF2 shows the shortening of the phosphate chains. Hardness and density of glass samples were measured and correlated with the composition of glasses.

  20. Removal of hexavalent chromium from aqueous solution by barium ion cross-linked alginate beads

    Directory of Open Access Journals (Sweden)

    Uzaşçı Sesil

    2014-07-01

    Full Text Available Barium ion cross-linked alginate beads have shown great affinity to toxic hexavalent chromium ions in aqueous solution, contrary to the traditional calcium alginate beads. The adsorption experiments were carried out by the batch contact method. The optimal pH for removal was found to be pH 4. The equilibrium was established in 4 h and the removal efficiency of chromium (VI was found as 95%. The adsorption data fit well with Langmuir and Freundlich isotherms. The maximum chromium (VI adsorption capacity determined from Langmuir isotherm was 36.5 mg/g dry alginate beads. Our study suggests that barium alginate beads can be used as cost-effective and efficient adsorbents for the removal of chromium (VI from contaminated waters.

  1. Single-step synthesis of well-crystallized and pure barium titanate nanoparticles in supercritical fluids

    Science.gov (United States)

    Reverón, Helen; Aymonier, Cyril; Loppinet-Serani, Anne; Elissalde, Catherine; Maglione, Mario; Cansell, François

    2005-08-01

    Single-step synthesis of ultra-fine barium titanate powder with a crystallinity as high as 90% and without barium carbonate contamination has been successfully performed under supercritical conditions using a continuous-flow reactor in the temperature range 150-380 °C at 16 MPa. To synthesize this bimetallic oxide, alkoxides, ethanol and water were used. The influence of the synthesis parameters on the BaTiO3 powder characteristics was investigated. The results show that the water to alkoxide precursor ratio, the reactor temperature and the Ba:Ti molar ratio of alkoxide precursor play a major role in the crystallization of pure and well-crystallized BaTiO3 nanoparticles. The continuous mode of operation without post-treatments for powder washing, drying or crystallization increase the industrial interest.

  2. Barium hexaferrite/graphene oxide: controlled synthesis and characterization and investigation of its magnetic properties

    Science.gov (United States)

    Maddahfar, Mahnaz; Ramezani, Majid; Mostafa Hosseinpour-Mashkani, S.

    2016-08-01

    In the present study, barium hexaferrite nanocrystals (BaFe12O19) were successfully synthesized through the two-step sol-gel method in an aqueous solution in the presence of barium nitrate and iron (III) nitrate. Besides, the effect of the molar ratio of graphene oxide on the particle size and magnetic properties of final product was investigated. In this research, glucose plays a role as capping and chelating agent in the synthesis of BaFe12O19/graphene oxide. Moreover, it was found that the size, morphology, and magnetic properties of the final products could be greatly influenced by the molar ratio of graphene oxide. BaFe12O19/graphene oxide was characterized by using X-ray diffraction, scanning electron microscope, Fourier transform infrared spectroscopy, vibrating sample magnetometer, and energy-dispersive spectrometry.

  3. Magnetic and dielectric properties of 3Y-TZP/strontium doped barium ferrite composite

    Science.gov (United States)

    Zhang, Chao; Wang, Shan-Shan; Guo, Rui-Song; Cai, Guang-Lan; Guo, Wei-Na; Wu, Chen

    2015-02-01

    Magnetic and dielectric properties of 3Y-TZP/20 wt.% Ba1-xSrxFe12O19 (x = 0, 0.25, 0.5, 0.75) composites prepared by solid state reaction method are investigated. The magnetic properties are improved in the composites with the strontium doped barium ferrite. When x = 0.25, the saturation magnetization of the ferrite reaches the maximum. This is due to the migration of Fe3+ induced by the Sr2+ doping. The dielectric properties are also improved in the composite with the strontium doped barium ferrite. When x = 0.5, the dielectric constant and dielectric loss possess the maximum. This is caused by the lattice distortion resulting from the Sr2+ doping. The dielectric properties are analyzed by the universal relaxation law.

  4. The CAMEO barium release - E/parallel/ fields over the polar cap

    Science.gov (United States)

    Heppner, J. P.; Miller, M. L.; Pongratz, M. B.; Smith, G. M.; Smith, L. L.; Mende, S. B.; Nath, N. R.

    1981-01-01

    Four successive thermite barium releases at an altitude of 965 km over polar cap invariant latitudes 84 to 76 deg near magnetic midnight were conducted from the orbiting second stage of the vehicle that launched Nimbus 7; the releases were made as part of the CAMEO (Chemically Active Material Ejected in Orbit) program. This was the first opportunity to observe the behavior of conventional barium release when conducted at orbital velocity in the near-earth magnetic field. The principal unexpected characteristic in the release dynamics was the high, 1.4 to 2.6 km/s, initial Ba(+) expansion velocity relative to an expected velocity of 0.9 km/s. Attention is also given to neutral cloud expansion, initial ion cloud expansion, convective motion, and the characteristics of field-aligned motion. The possibility of measuring parallel electric fields over the polar cap by observing perturbations in the motion of the visible ions is assessed.

  5. Examination of colon with diluted barium contrast medium by the irrigoscopic (irrigographic) method

    International Nuclear Information System (INIS)

    By analogy with the work of C.Tavernier et al. (1974), who examined the eosophagus, stomach and duodenum with diluted 23% barium sulphate solution, the authors examined 58 patients by irrigoscopy (irrigography) with 20% barium sulphate solution. The rationality and the advantages of the method over the standard one were demonstrated. Early lesions measuring 3 or 4 mm were detected; the mucosal relief was very well presented. The injurious effect of tannic acid on the liver parenchyma was avoided by the use of low 0.15% tannin solution. In comparison with the method of Fischer (with double contrast) the examination time was shortened and the radiation load to the patients and attending personal reduced. The method is technically easy to perform. (author)

  6. Isolation and characterisation of barium sulphate and titanium oxides in monument crusts

    International Nuclear Information System (INIS)

    Black crusts from historical ornamental materials contain Ba and Ti. These elements are in low proportion, making their determination difficult and especially the characterisation of the phases in which they are present. For this reason, works on the mineralogical composition of the two elements in black crusts is scarce. Thus the isolation, previous to their characterisation, is important for the study of the surface layer in altered monuments. An acid attack for the isolation of barium sulphate and titanium oxides in black crusts from polluted areas has been used. The acid employed is a mixture of HF, HNO3 and HClO4. The residue isolated by acid attack was analysed by energy dispersive X-ray fluorescence and X-ray diffraction. It was characterised, and the percentages of barite (barium sulphate), anatase (titanium oxide), and rutile (titanium oxide) phases present in the surface layers were calculated

  7. The removal of radiostrontium by means of barium sulphate precipitation, ch. 4

    International Nuclear Information System (INIS)

    The barium sulphate precipitation method which is less-commonly used for the purification of radioactive wastewater is examined. In batch experiments, source variables influencing the process are studied. Results are tested in continuous processes. It was shown that the addition of stoichiometric amounts of precipitants at the same time rendered no more than 60% removal of radiostrontium; the addition of excess sulphate ions resulted in 99.7% removal. This can also be achieved by slow addition of a stoichiometric amount of barium ions to a solution containing sulphate ions and the radioisotope. The binding process is multilayer occlusion, but when more than the stoichiometric amount is added the continuing process is normal adsorption. The process is pH-independent; there is little interference of foreign ions. The method was also tested for the removal of ruthenium-106 and cobalt-60 and was successfully applied in the case of ruthenium

  8. Effects of barium sulfate as a contrast medium to enterocutaneous fistulas

    International Nuclear Information System (INIS)

    Fistulation following thoracic and epigastric interventions are conservatively treated, as a rule, because of the high rate of complications expected from reoperation. With properly functioning anastomotic transit, insufficiencies usually undergo spontaneous healing, within four to six weeks. Enterocutaneous fistulae developed in 29 of 271 patients with intrathoracic oesophagastric or oesophagojejunal anastomosis. Syringeal ramification into pleural or abdominal cavities were eliminated by means of an absorbable contrast medium, before barium sulphate was orally administered to all patients. Thoracic fistulae were closed after 21.8 days on average, while 20.3 days was the average period required for closure of epigastric fistulae. Barium sulphate was found to stimulate fistular tissue granulation, so that obliteration of the fistular system occurred much sooner, as compared to conservative treatment. The patient's quality of life can thus be improved, and hospitalisation can be shortened. Neither locally delimited nor systemic complications were observed in any of the cases described. (author)

  9. Gamma-ray shielding and structural properties of barium-bismuth-borosilicate glasses

    Science.gov (United States)

    Bootjomchai, Cherdsak; Laopaiboon, Jintana; Yenchai, Chadet; Laopaiboon, Raewat

    2012-07-01

    The attenuation coefficients of barium-bismuth-borosilicate glasses have been measured for gamma-ray photon energies of 662, 1173 and 1332 keV using a narrow beam transmission geometry. These coefficients were then used to obtain the values of mass attenuation coefficients, effective atomic number, effective electron density and mean free path. Good agreement has been observed between experimental and theoretical values of these parameters. From the obtained results it is reported here that from the barium-bismuth-borosilicate glasses are better shields to gamma-radiations in comparison to the standard radiation shielding concretes from the shielding point of view. The molar volume, FTIR and acoustic investigations have been used to study the structural properties of the prepared glass system. The obtained results reveal that the formation of non-bridging oxygens occurs at higher concentration of Bi2O3.

  10. Correlated Strontium and Barium Isotopic Compositions of Acid-Cleaned Single Silicon Carbides from Murchison

    CERN Document Server

    Liu, Nan; Gallino, Roberto; Davis, Andrew M; Bisterzo, Sara; Gyngard, Frank; Kaeppeler, Franz; Cristallo, Sergio; Dauphas, Nicolas; Pellin, Michael J; Dillmann, Iris

    2015-01-01

    We present strontium, barium, carbon, and silicon isotopic compositions of 61 acid-cleaned presolar SiC grains from Murchison. Comparison with previous data shows that acid washing is highly effective in removing both strontium and barium contamination. For the first time, by using correlated $^{88}Sr$/$^{86}Sr$ and $^{138}Ba$/$^{136}Ba$ ratios in mainstream SiC grains, we are able to resolve the effect of $^{13}C$ concentration from that of $^{13}C$-pocket mass on s-process nucleosynthesis, which points towards the existence of large $^{13}C$-pockets with low $^{13}C$ concentration in AGB stars. The presence of such large $^{13}$R-pockets with a variety of relatively low $^{13}C$ concentrations seems to require multiple mixing processes in parent AGB stars of mainstream SiC grains.

  11. Effect of Mg-Zr substitution and microwave processing on magnetic properties of barium hexaferrite

    Science.gov (United States)

    Sharma, Manju; Kashyap, Subhash C.; Gupta, H. C.

    2014-09-01

    The effect of substitution of Mg-Zr for Fe in M-type barium hexaferrite (BHF) and of processing technique on the magnetic properties and microstructure has been reported in the present paper. Significant changes in magnetic properties have been observed on substituting Fe ions by Mg and Zr ions in M-type barium hexaferrite, i.e. BaFe12O19 as well as by single mode microwave processing. The single mode microwave processing of the undoped sample reduced the coercivity to nearly 25% of the value for the sintered sample along with the enhancement in magnetization, thereby making it suitable for memory devices. The improvement in magnetic properties is explained on the basis of microstructure. The addition of substituents, though assisted in the formation of single phase, it, however, degraded the magnetization besides decreasing the coercivity, possibly due to substitution at the octahedral sites.

  12. Stimulation of natural killer cells with a CD137-specific antibody enhances trastuzumab efficacy in xenotransplant models of breast cancer

    Science.gov (United States)

    Kohrt, Holbrook E.; Houot, Roch; Weiskopf, Kipp; Goldstein, Matthew J.; Scheeren, Ferenc; Czerwinski, Debra; Colevas, A. Dimitrios; Weng, Wen-Kai; Clarke, Michael F.; Carlson, Robert W.; Stockdale, Frank E.; Mollick, Joseph A.; Chen, Lieping; Levy, Ronald

    2012-01-01

    Trastuzumab, a monoclonal antibody targeting human epidermal growth factor receptor 2 (HER2; also known as HER-2/neu), is indicated for the treatment of women with either early stage or metastatic HER2+ breast cancer. It kills tumor cells by several mechanisms, including antibody-dependent cellular cytotoxicity (ADCC). Strategies that enhance the activity of ADCC effectors, including NK cells, may improve the efficacy of trastuzumab. Here, we have shown that upon encountering trastuzumab-coated, HER2-overexpressing breast cancer cells, human NK cells become activated and express the costimulatory receptor CD137. CD137 activation, which was dependent on NK cell expression of the FcγRIII receptor, occurred both in vitro and in the peripheral blood of women with HER2-expressing breast cancer after trastuzumab treatment. Stimulation of trastuzumab-activated human NK cells with an agonistic mAb specific for CD137 killed breast cancer cells (including an intrinsically trastuzumab-resistant cell line) more efficiently both in vitro and in vivo in xenotransplant models of human breast cancer, including one using a human primary breast tumor. The enhanced cytotoxicity was restricted to antibody-coated tumor cells. This sequential antibody strategy, combining a tumor-targeting antibody with a second antibody that activates the host innate immune system, may improve the therapeutic effects of antibodies against breast cancer and other HER2-expressing tumors. PMID:22326955

  13. Cesium-137 Levels Detected in Otters from Austria

    Directory of Open Access Journals (Sweden)

    Gutleb A.C.

    1991-02-01

    Full Text Available Pollution seems to be one of the most important causes for the decline of the European otter (Lutra lutra. The accident in the Chernobyl nuclear power plant added another aspect to environmental pollution. Few data on cesium-137 contents in otters are available, so levels were measured in 3 otters from Austria. All levels found were very low.

  14. Cs-137 in soil erosion and siltation assessment in Romania

    International Nuclear Information System (INIS)

    The investigation was carried out in the frame of CRP 8819/RO contract between IAEA-Vienna and IFIN-HH. The investigated areas are located in the southern part of Romanian Moldavian Table Land. The areas are known as being the most eroded in Romania and soil preservation and erosion countermeasures were applied in this region. Antohesti reservoir from Berheci watershed is placed in an area with high relief energy. The lowest altitude, in front of the dam is 210 m and the highest altitude with 561 m is the top of Dorsan Hill. The specific activity of Cs-137 in two core samples of sediment from Antohesti reservoir were measured. In this area there are several discontinuous gullies in which the erosion of soil and subsequent sedimentation processes are very intense. The profile distribution of Cs-137 in sediment is presented. Several gully head agraded soil samples were taken and analyzed. The profile distribution of Cs-137 in aggraded soil of the gully heads, the presence of Cs-137 up to 200-250 cm due to fallout deposition from nuclear tests and the maxima corresponding to the years 1959, 1963 and 1986 are clearly highlighted. The mean aggradation rate is about 6 cm/year. (author)

  15. Strontium-90 and cesium-137 in fresh water

    International Nuclear Information System (INIS)

    Japan Chemical Analysis Center has analysed the strontium-90 and Cesium-137 contents in fresh water from 7 prefectures in Japan by the commission of Science and Technology Agency of Japanese Government. The method described in ''Radioactivity Survey Data in Japan No. 43 (NIRS-RSD-43, 1977) was applied to the analysis of these two radionuclides in samples. (author)

  16. 137Cs in the fungal compartment of Swedish forest soils

    International Nuclear Information System (INIS)

    The 137Cs activities in soil profiles and in the mycelia of four ectomycorrhizal fungi were studied in a Swedish forest in an attempt to understand the mechanisms governing the transfer and retention of 137Cs in forest soil. The biomass of four species of fungi was determined and estimated to be 16 g m-2 in a peat soil and 47-189 g m-2 in non-peat soil to the depth of 10 cm. The vertical distribution was rather homogeneous for two species (Tylospora spp. and Piloderma fallax) and very superficial for Hydnellum peckii. Most of the 137Cs activity in mycelium of non-peat soils was found in the upper 5 cm. Transfer factors were quite high even for those species producing resupinate sporocarps. In the peat soil only approximately 0.3% of the total 137Cs inventory in soil was found in the fungal mycelium. The corresponding values for non-peat soil were 1.3, 1.8 and 1.9%

  17. Neutron beam test of barium fluoride crystal for dark matter direct detection

    Science.gov (United States)

    Guo, C.; Ma, X. H.; Wang, Z. M.; Bao, J.; Dai, C. J.; Guan, M. Y.; Liu, J. C.; Li, Z. H.; Ren, J.; Ruan, X. C.; Yang, C. G.; Yu, Z. Y.; Zhong, W. L.

    2016-10-01

    In order to test the capabilities of Barium Fluoride (BaF2) crystal for dark matter direct detection, nuclear recoils are studied with mono-energetic neutron beam. The energy spectra of nuclear recoils, quenching factors for elastic scattering neutrons and discrimination capability between neutron inelastic scattering events and γ events are obtained for various recoil energies of the F content in BaF2.

  18. Barium strontium titanate thin film varactors for room-temperature microwave device applications

    International Nuclear Information System (INIS)

    Recent progress in the development of barium strontium titanate thin film varactors for room temperature tunable microwave devices applications is reviewed, with emphasis on efforts towards the improvement in the quality of BST thin films and the fabrication issues crucial for the performance of microwave devices based on BST varactors. The paper provides examples of tunable microwave devices employing BST varactors. Other thin film materials currently competing with BST thin films are discussed. Topics which deserve further investigation are suggested. (topical review)

  19. Radiographer and radiologist perception error in reporting double contrast barium enemas: A pilot study

    International Nuclear Information System (INIS)

    Purpose: The practice of radiographers performing double contrast barium enemas (DCBE) is now widespread and in many centres the radiographer's opinion is, at least, contributing to a dual reporting system [Bewell J, Chapman AH. Radiographer performed barium enemas - results of a survey to assess progress. Radiography 1996;2:199-205; Leslie A, Virjee JP. Detection of colorectal carcinoma on double contrast barium enema when double reporting is routinely performed: an audit of current practice. Clin Radiol 2001;57:184-7; Culpan DG, Mitchell AJ, Hughes S, Nutman M, Chapman AH. Double contrast barium enema sensitivity: a comparison of studies by radiographers and radiologists. Clin Radiol 2002;57:604-7]. To ensure this change in practice does not lead to an increase in reporting errors, this study aimed to compare the perception abilities of radiographers with those of radiologists. Methods: Three gastro-intestinal (GI) radiographers and three consultant radiologists independently reported on a selection of 50 DCBE examinations, including the level of certainty in their comments for each examination. A blinded comparison of the results with an independent 'standard report' was recorded. Results: The results demonstrate there was no significant difference in perception error for any of the levels of certainty, for single reporting, for double reading by a radiographer/radiologist or by two radiologists. Conclusions: The study shows that radiographers can perceive abnormalities on DCBE at similar sensitivities and specificities as radiologists. While the participants in the study may be typical of a district general hospital, the nature of the study gives it limited external validity. As a pilot, the results demonstrate that, with slight modification, the methodology could be used for a larger study

  20. High Performance, Low Temperature Solution-Processed Barium and Strontium Doped Oxide Thin Film Transistors

    OpenAIRE

    Banger, Kulbinder K.; Peterson, Rebecca L.; Mori, Kiyotaka; Yamashita, Yoshihisa; Leedham, Timothy; Sirringhaus, Henning

    2013-01-01

    Amorphous mixed metal oxides are emerging as high performance semiconductors for thin film transistor (TFT) applications, with indium gallium zinc oxide, InGaZnO (IGZO), being one of the most widely studied and best performing systems. Here, we investigate alkaline earth (barium or strontium) doped InBa(Sr)ZnO as alternative, semiconducting channel layers and compare their performance of the electrical stress stability with IGZO. In films fabricated by solution-processing from metal alkoxide ...

  1. Phase conjugation, isotropic and anisotropic higher order diffraction generation, and image correlation using photorefractive barium titanate

    Science.gov (United States)

    Buranasiri, Prathan

    2005-04-01

    Using barium titanate as the photorefractive material, we demonstrate phase conjugation, beam coupling, higher diffraction order generation. At small incident angles less than 0.015 radian, both codirectional isotropic self-diffraction (CODIS) and contradirectional isotropic self-diffraction (CONDIS) are generated simultaneously. At bigger incident angles approximately more than 0.2094 radian, only codirectional anisotropic-self diffraction (CODAS) are generated. On going imaging correlation is also showing.

  2. Barium ferrite/epoxy resin nanocomposite system: Fabrication, dielectric, magnetic and hydration studies

    OpenAIRE

    A. Kanapitsas; C. Tsonos; G. C. Psarras; S. Kripotou

    2016-01-01

    Composite systems of epoxy resin and barium ferrite nanoparticles have been prepared, and studied varying the content of the inclusions. Morphology of prepared samples has been examined via scanning electron microscopy and X-ray diffraction spectra, while electrical and magnetic properties were investigated by means of broadband dielectric spectroscopy, and magnetization tests respectively. Finally, water vapor sorption measurements were conducted in order to study the water sorption dynamics...

  3. Neutron Beam Tests of Barium Fluoride Crystal for Dark Matter Direct Detection

    CERN Document Server

    Guo, Cong; Wang, Zhimin; Bao, Jie; Dai, Changjiang; Guan, Mengyun; Liu, Jinchang; Li, Zuhao; Ren, Jie; Ruan, Xichao; Yang, Changgen; Yu, Zeyuan; Zhong, Weili

    2016-01-01

    In order to test the capabilities of Barium Fluoride (BaF2) Crystal for dark matter direct detection, nuclear recoils are studied with mono-energetic neutron beam. The energy spectra of nuclear recoils, quenching factors for elastic scattering neutrons and discrimination capability between neutron inelastic scattering events and {\\gamma} events are obtained for various recoil energies of the F content in BaF2.

  4. Effect of boric acid sintering aid on densification of barium ferrite

    Indian Academy of Sciences (India)

    S S Vidyawathi; R Amaresh; L N Satapathy

    2002-11-01

    Boric acid has been added in 0.1–0.6% range for studying the densification characteristics of solid state sintered barium hexaferrite. Sintering studies have been carried out at three different temperatures. Physical properties like density and porosity have been studied for all compositions. The phase identification and microstructural investigation on the fractured surface have been carried out to understand the effect of sintering aid on the densification characteristics.

  5. Modification of gray iron produced by induction melting with barium strontium

    Science.gov (United States)

    Modzelevskaya, G.; Feoktistov, A. V.; Selyanin, I. F.; Kutsenko, A. I.; Kutsenko, A. A.

    2016-09-01

    The article provides analysis of results of gray iron experimental melts in induction furnace and the following melt modification with barium-strontium carbonate (BSC-2). It is shown that modification positively affects mechanical and casting properties and as-cast iron structure. It was established that BSC-2 granulated immediately prior to use has greater impact on melt than BSC-2 of the same faction, supplied by the manufacturer.

  6. Electrical Properties of Thin-Film Capacitors Fabricated Using High Temperature Sputtered Modified Barium Titanate

    OpenAIRE

    Robert Mamazza; Heinz Felzer; Martin Dubs; Glyn J. Reynolds; Martin Kratzer

    2012-01-01

    Simple thin-film capacitor stacks were fabricated from sputter-deposited doped barium titanate dielectric films with sputtered Pt and/or Ni electrodes and characterized electrically. Here, we report small signal, low frequency capacitance and parallel resistance data measured as a function of applied DC bias, polarization versus applied electric field strength and DC load/unload experiments. These capacitors exhibited significant leakage (in the range 8–210 μA/cm2) and dielectric loss. Measur...

  7. The use of radioanalytical methods in nucleation and crystal growth studies. The barium sulphate system

    International Nuclear Information System (INIS)

    The spontaneous precipitation of barium sulphate in aqueous solutions was followed by counting the 131Ba specific activity in the aqueous phase. The main advantages of this method were the increased sensitivity and the possibility of monitoring the process to a larger extent in comparison with other techniques. Kinetics parameters including the size of the critical nucleus and the surface energy of the precipitating solid were estimated according to the model for polynuclear growth. (Author)

  8. Establishment of a protocol for determining gastrointestinal transit time in mice using barium and radiopaque markers

    Energy Technology Data Exchange (ETDEWEB)

    Myagmarjaibuu, Bilomaa; Moon, Myeong Ju; Heo, Suk Hee; Jeong, Seo In; Jeong, Yong Yeon; Kang, Heoung Keun [Dept. of Radiology, Chonnam National University Hwasun Hospital, Chonnam National University Medical School, Hwasun (Korea, Republic of); Park, Jong Seong [Dept. of Physiology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Jun, Jae Yeoul [Dept. of Physiology, College of Medicine, Chosun University, Gwangju (Korea, Republic of)

    2013-01-15

    The purpose of this study was to establish a minimally invasive and reproducible protocol for estimating the gastrointestinal (GI) transit time in mice using barium and radiopaque markers. Twenty 5- to 6-week-old Balb/C female mice weighing 19-21 g were used. The animals were divided into three groups: two groups that received loperamide and a control group. The control group (n = 10) animals were administered physiological saline (1.5 mL/kg) orally. The loperamide group I (n = 10) and group II (n = 10) animals were administered 5 mg/kg and 10 mg/kg loperamide orally, respectively. Thirty minutes after receiving the saline or loperamide, the mice was administered 80 μL of barium solution and six iron balls (0.5 mm) via the mouth and the upper esophagus by gavage, respectively. Afterwards, the mice were continuously monitored with fluoroscopic imaging in order to evaluate the swallowing of the barium solution and markers. Serial fluoroscopic images were obtained at 5- or 10-min intervals until all markers had been excreted from the anal canal. For analysis, the GI transit times were subdivided into intestinal transit times (ITTs) and colon transit times (CTTs). The mean ITT was significantly longer in the loperamide groups than in the control group (p < 0.05). The mean ITT in loperamide group II (174.5 ± 32.3) was significantly longer than in loperamide group I (133.2 ± 24.2 minute) (p < 0.05). The mean CTT was significantly longer in loperamide group II than in the control group (p < 0.05). Also, no animal succumbed to death after the experimental procedure. The protocol for our study using radiopaque markers and barium is reproducible and minimally invasive in determining the GI transit time of the mouse model.

  9. Hybrid Nd-Fe-B/barium ferrite magnetic materials with epoxy matrix

    OpenAIRE

    Stajčić Aleksandar P.; Stajić-Trošić Jasna T.; Aleksić Radoslav R.; Žák Tomáš; Lazić Nada L.; Stijepović Mirko Z.; Grujić Aleksandar S.

    2012-01-01

    Lately a great attention has been paid to the research of bonded hybrid composites with improved dynamic mechanical capacities capable of replacing bonded Nd-Fe-B magnetic materials, by using the cheaper (ferrite) materials instead of the Nd-Fe-B powder while retaining the satisfying values of the maximal magnetic energy. The objective of this study is to assess how different contents of Nd-Fe-B and/or barium ferrite particles can affect morphological, dynamic mechanical and magnetic pr...

  10. Transfer of cadmium and barium from soil to crops grown in tropical soils

    OpenAIRE

    Leônidas Carrijo Azevedo Melo; Evandro Barbosa da Silva; Luís Reynaldo Ferracciú Alleoni

    2014-01-01

    Phytotoxicity and transfer of potentially toxic elements, such as cadmium (Cd) or barium (Ba), depend on the availability of these elements in soils and on the plant species exposed to them. With this study, we aimed to evaluate the effect of Cd and Ba application rates on yields of pea (Pisum sativum L.), sorghum (Sorghum bicolor L.), soybean (Glycine max L.), and maize (Zea mays L.) grown under greenhouse conditions in an Oxisol and an Entisol with contrasting physical and chemical properti...

  11. Growth and study of barium oxalate single crystals in agar gel

    Indian Academy of Sciences (India)

    P V Dalal; K B Saraf

    2006-10-01

    Barium oxalate was grown in agar gel at ambient temperature. The effect of various parameters like gel concentration, gel setting time and concentration of the reactants on the growth of these crystals was studied. Prismatic platy shaped spherulites and dendrites were obtained. The grown crystals were characterized by X-ray powder diffractometry, infrared spectroscopy, thermogravimetric and differential thermal analysis. An attempt is made to explain the spherulitic growth mechanism.

  12. Randomized clinical trial on the use of antispasmodic drugs in barium enema: impact on radiological practice

    International Nuclear Information System (INIS)

    Purpose: To assess the willingness of radiologists to change their practice when the results of a randomized clinical trial (RCT) on the use of antispasmodic drugs in barium enema are presented. Materials and Methods: During the years 1994 and 1995 two postal questionnaires were sent to 481 practicing radiologists who were all members of the Netherlands Society of Radiology. In the first questionnaire the respondents were asked to give the characteristics of their practices in performing daily barium enema. The data from this questionnaire was used as a reference. The second questionnaire was sent to the respondents together with an abstract on the randomized clinical trial supporting the use of antispasmodic drugs in barium enema. We also indicated a preference for Buscopan over Glucagon as the antispasmodic drug. The willingness to change prescription habits was measured by comparing the data of the two questionnaires. Results: Of 481 practicing radiologists, 312 responded to the first questionnaire and gave information of their prescription habits (response rate 64%). These 312 responders were sent an abstract of the RCT and were asked to fill out a second questionnaire to determine their willingness to change their practice. Two hundred and sixty-seven radiologists responded (response rate 86%). A significant number of 119 (51%) were willing to increase the use of antispasmodic drugs. A significant number of 128 (55%) chose to increase the use of Buscopan, while a significant number of 81 (32%) were willing to decrease the use of Glucagon. Conclusion: Direct exposure to the results of an RCT recommending the use of antispasmodic drugs in barium enema, especially Buscopan, is likely to increase its use by practicing radiologists

  13. The burden of cesium 137 in forest clerks; Die Belastung mit Caesium 137 bei Beschaeftigten der Forstverwaltung

    Energy Technology Data Exchange (ETDEWEB)

    Piechotowski, I.; Jaroni, J. [Landesgesundheitsamt Baden-Wuerttemberg, Stuttgart (Germany); Link, B. [Arbeits- und Sozialministerium des Landes Baden-Wuerttemberg, Stuttgart (Germany); Groezinger, O. [Ministerium fuer Umwelt und Verkehr des Landes Baden-Wuerttemberg, Stuttgart (Germany)

    2000-07-01

    In 47 forest clerks from the regions Ortenau and Oberschwaben in south-west Germany the incorporation of cesium 137 and potassium 40 was measured in autumn 1994. Soil burden as well as burden of nutrition with cesium 137 are different in these regions for geological reasons and as a result of the nuclear accident of Chernobyl. Caused by low content of clay in Oberschwaben, the transfer of cesium to plants is assisted. Heavy rainfall after the nuclear accident led to an additional increase of burden. The median of the concentration of cesium 137 was 1.4 Bq/kg body weight. The median for potassium 40 was 58 Bq/kg body weight. For cesium 137 regional differences were observed. For persons from Oberschwaben the median for cesium 137 was with 2.8 Bq/kg body weight clearly higher than for persons from Ortenau with 0,6 Bq/kg body weight. Concerning nutrition habits, the clearest difference was found comparing persons who had ate a minimum of four portions of deer from the surroundings within the last four weeks with persons who had ate less than four portions of deer from the surroundings within the last four weeks. The difference was greater in Oberschwaben than in Ortenau. The effective dose of cesium 137 calculated on the basis of the incorporation is very low compared to natural radiation. This is also valid for persons from Oberschwaben. (orig.) [German] Im Herbst 1994 wurde bei insgesamt 47 Bediensteten der Forstverwaltung aus den Regionen Ortenaukreis und Oberschwaben die Inkorportation an Caesium 137 und Kalium 40 gemessen. Sowohl die Bodenbelastung als auch die Belastung von Nahrungsmitteln mit Caesium 137 unterscheiden sich in diesen Gebieten bedingt durch geologische Besonderheiten und in Folge des Reaktorunfalls von Tschernobyl. Aufgrund eines geringen Anteils an Tonerden wird in Oberschwaben der Caesiumtransfer in Pflanzen beguenstigt, eine zusaetzliche Erhoehung der Belastung erfolgte durch starke Niederschlaege nach dem Reaktorunfall. Die Konzentration fuer

  14. Yield and ion distribution for the barium cloud at 31,000 kilometers, September 21, 1971.

    Science.gov (United States)

    Manring, E. R.; Patty, R. R.

    1973-01-01

    The photon flux density associated with the 4554-A resonance radiation for Ba II was measured at Mount Hopkins, Arizona, and Cerro Morado, Chile, and was determined to be 36,000 photon/sq cm sec outside the atmosphere; this measurement was made when the cloud was optically thin at 120 sec after release. Using this and a photon scattering efficiency of 0.66 photon/ion sec we estimate a 1.7-kg yield of barium ions that are formed from the initially released atomic barium and are thus associated with the main core of the cloud. Photographic and photometric data are combined to obtain preliminary values for the brightness throughout the cloud for two photographs, and isobrightness plots are presented. These plots indicate that the cloud is quite narrow, that a considerable portion of the ionized barium is outside the main core after a few minutes, and that the striations contain only a small fraction of the total material.

  15. Luminescence of Er3+ Doped Titanium Barium Glass Microsphere under 514 nm Excitation

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The titanium barium glass microspheres doped with Er2O3 were designed and prepared. The components of the glass sample were 25TiO2-27BaCO3-8Ba(NO3)2-5ZnO2-10CaCO3-5H3BO3-10SiO2-7water glass-3Er2O3 (%, mass fraction). The emission spectra of titanium barium glass matrix and the titanium barium glass microsphere under 514 nm excitation were measured with micro-Raman spectrometer. Whispering gallery modes in the emission spectra from a 31 μm glass microsphere were observed. Many regularly spaced, sharp peaks appeared in the emission spectra of the Er2O3-doped glass microsphere. The wavelength separation between the two adjacent peaks is 1.92 nm for the 31 μm microsphere. According to the Lorenz-Mie formula, the calculated value of the wavelength separation between the two adjacent peaks is 1.95 nm. The observed resonances could be assigned by using the well-known Lorenz-Mie formula.

  16. An effective quantum defect theory for the diamagnetic spectrum of a barium Rydberg atom

    Institute of Scientific and Technical Information of China (English)

    Li Bo; Liu Hong-Ping

    2013-01-01

    A theoretical calculation is carried out to investigate the spectrum of a barium Rydberg atom in an external magnetic field.Using an effective approach incorporating quantum defect into the centrifugal term in the Hamiltonian,we reexamine the reported spectrum of the barium Rydberg atom in a magnetic field of 2.89 T [J.Phys.B 28 L537 (1995)].Our calculation employs B-spline basis expansion and complex coordinate rotation techniques.For single photon absorption from the ground 6s2 to 6snp Rydberg states,the spectrum is not influenced by quantum defects of channels ns and nd.The calculation is in agreement with the experimental observations until the energy reaches E =-60 cm-1.Beyond this energy,closer to the threshold,the calculated and experimental results do not agree with each other.Possible reasons for their discrepancies are discussed.Our study affirms an energy range where the diamagnetic spectrum of the barium atom can be explained thoroughly using a hydrogen model potential.

  17. Effects of Dysprosium Oxide Doping on Microstructure and Properties of Barium Titanate Ceramic

    Institute of Scientific and Technical Information of China (English)

    Pu Yongping; Ren Huijun; Chen Wei; Chen Shoutian

    2005-01-01

    Different amounts of dysprosium oxide were incorporated into barium titanate powders synthesized by hydrothermal method. Relations of substitution behaviors and lattice parameters with solid-solubility were studied. Furthermore, the influences of dysprosium oxide doping fraction on grain size and dielectric properties of barium titanate ceramic, including dielectric constant and breakdown electric field strength, were investigated via scanning electron microscope, X-ray diffraction and electric property tester. The results show that dysprosium oxide can restrain abnormal grain growth during sintering and that fine-grained and high density of barium titanate ceramic can result in excellent dielectric properties. As mass fraction of dysprosium oxide is 0.6%, the lattice parameters of grain increase to the maximum because of the lowest vacancy concentration. The electric property parameters are cited as following: dielectric constant (25 ℃) reaches 4100, the change in relative dielectric constant with temperature is -10% to 10% within the range of -15~100 ℃, breakdown electric field strength (alternating current) achieves 3.2 kV·mm-1, which can be used in manufacturing high voltage ceramic capacitors.

  18. Er3+-substituted W-type barium ferrite: preparation and electromagnetic properties

    Institute of Scientific and Technical Information of China (English)

    HUANG

    2010-01-01

    Er3+-substituted W-type barium ferrites Ba1-xErx(Zn0.3Co0.7)2Fe16O27(x=0.00,0.05,0.10,0.15,0.20)were synthesized by polymer adsorbent combustion method.Samples were characterized by X-ray diffraction analysis(XRD),X-ray fluorescence(XRF),scanning electron microscopy(SEM)and network analyzer to investigate the relationships among Er3+concentration,crystal structure,surface mcrphology and electromagnetic properties.All the XRD patterns showed pure phase of W-type barium ferrite when x≤0.15,while the impurity phase of ErFeO3 appeared when x=0.20.The pure W-type barium ferrite showed a hexagonal flake shape.In addition,the microwave electromagnetic properties of samples were analyzed in the frequency range of 2-18 GHz.It was indicated that the electromagnetic properties were significantly improved when Er3+doping content was 0.10.The reasons were also discussed using electromagnetic theory.The optimized ferrite exhibited excellent microwave absoption performance.The maximum of reflection loss(RL)reached about-27.4 dB and RL was below-10dB at the frequency range from 8.4 GHz to 18 GHz,when the thickness was 2.6 mm.

  19. A barium central star binary in the Type-I diamond ring planetary nebula Abell 70

    CERN Document Server

    Miszalski, B; Frew, D J; Acker, A; Köppen, J; Moffat, A F J; Parker, Q A

    2011-01-01

    Abell 70 (PN G038.1-25.4, hereafter A 70) is a planetary nebula (PN) known for its diamond ring appearance due a superposition with a background galaxy. The previously unstudied central star is found to be a binary consisting of a G8IV-V secondary at optical wavelengths and a hot white dwarf (WD) at UV wavelengths. The secondary shows Ba II and Sr II features enhanced for its spectral type that, combined with the chromospheric Halpha emission and possible 20-30 km/s radial velocity amplitude, firmly classifies the binary as a Barium star. The proposed origin of Barium stars is intimately linked to PNe whereby wind accretion pollutes the companion with dredged-up material rich in carbon and s-process elements when the primary is experiencing thermal pulses on the Asymptotic Giant Branch (AGB). A 70 provides further evidence for this scenario together with the other very few examples of Barium central stars. The nebula is found to have Type-I chemical abundances with helium and nitrogen enrichment, which when c...

  20. Hydrothermal Synthesis and Characterization of Europium-dop ed Barium Titanate Nano crys-tallites

    Institute of Scientific and Technical Information of China (English)

    Margarita Garca-Hernandez; Genevieve Chadeyron; Damien Boyer; Antonieta Garca-Murillo; Felipe Carrillo-Romo; Rachid Mahiou

    2013-01-01

    Barium titanate nanocrystallites were synthesized by a hydrothermal technique from barium chlo-ride and tetrabutyl titanate. Single-crystalline cubic perovskite BaTiO3 consisting of spherical particles with diameters ranging from 10 to 30 nm was easily achieved by this route. In order to study the influence of the syn-thesis process on the morphology and the optical properties, barium titanate was also prepared by a solid-state reaction. In this case, only the tetragonal phase which crystallizes above 900℃ was observed. High-temperature X-ray diffraction measurements were performed to investigate the crystallization temperatures as well as the particle sizes via the Scherrer formula. The lattice vibrations were evidenced by infrared spectroscopy. Eu3+was used as a structural probe, and the luminescence properties recorded from BaTiO3:Eu3+and elaborated by a solid-state reaction and hydrothermal process were compared. The reddish emission of the europium is increased by the nanometric particles.

  1. Studies of the processes of incorporation of calcium, strontium, barium and radium into bone tissue

    International Nuclear Information System (INIS)

    Alkaline earth elements incorporation into bone tissue are investigated. The study is aimed at collecting the data on improvement of metabolism model of these elements. The study includes kinetics of calcium, strontium, barium and radium - carried out on 120 rats of Wistar strain: incorporation processes of light and heavy alkaline earth elements (strontium and barium) as a function of age of the organism - carried out on 30 rabbits of Chinchilla strain in different age groups, as well as the rate of incorporation of calcium and barium into different bone tissue areas - carried out on 68 rabbits of the same strain in one age group. The main investigative techniques are: radiochemical methods, whole-body counting technique, quantitative autoradiography and microradiography, ''tetracycline test'', computer calculation methods. The following conclusions are reached: incorporation of alkaline earth elements into bone tissue is differentiated and depends on whether or not it is a light element (Ca, Sr) or heavy one (Ba, Ra), it depends also on the area of bone tissue in which the incorporation occurs

  2. A Preliminary Trial on the Use of Barium Chloride for Pregnancy Diagnosis in Sows

    Directory of Open Access Journals (Sweden)

    Ndu, A.

    2000-01-01

    Full Text Available Urine was collected twice daily (once in the morning and once in the afternoon for 5 days from 80 Yorkshire x Landrace crossbred gilts/sows made up of 40 non-pregnant and 40 pregnant pigs in an investigation to determine the possibility of using 1 % barium chloride solution for pregnancy diagnosis in pigs based on a previous report that addition of a few drops of 1 % barium chloride solution to bovine urine caused a white precipitate with non-pregnant but not with pregnant cows. The pregnant pigs were in various stages of gestation. Urine reaction to 1 % barium chloride was highly (P <0.01 dependent on the pregnancy status of the sows, the test being 100 % and 81 % effective in identifying non-pregnant and pregnant sows respectively. The sensitivity of the test in the gravid sows was significantly (P <0.05 influenced by and tended to increa-se with the stage of gestation, with 59 % of the sows in their first stage of gestation (<38 days post-coitum being correctly diagnosed as pregnant, and 95-100 % of those in their latter stages of gestation being so correctly diagnosed. Parity and time of day of performance of the test had no effect on urine reaction. It was concluded that the test was at least 95 % accurate when used as from about 39 days after breeding for pregnancy diagnosis in sows.

  3. Using 137Cs technique to quantify soil conservation capacities of different ecosystems in Wolong Natural Reserve, southwestern China

    Institute of Scientific and Technical Information of China (English)

    GAO Jun; OUYANG ZhiYun

    2007-01-01

    Reliable information about soil conservation capacities of different natural ecosystems is an important reference for the design of targeted erosion and sediment control strategies. The objective of this paper is to quantify the soil conservation capacities of different natural ecosystems that can represent different climatic zones. The 137Cs technique has been used to estimate soil redistribution rates in different natural ecosystems over the past 40 years in Wolong Nature Reserve. The reserve, transiting from the Chengdu plain to the Qinghai-Tibet plateau, maintains rich ecosystems from subtropical to frigid.The net soil erosion rates of 5 selected ecosystems that represent a warm coniferous-broadleaf-mixed forest, a cold-resistant deciduous taiga forest, a cold-resistant shrub, an evergreen cold-resistant taiga servation capacities are reversed in order. The reference inventories for 137Cs in different ecosystems velop effective erosion and sediment strategies in areas with similar climates should consider natural ecosystem types.

  4. 137Cs and 210Pb distribution in Manila Bay sediment

    International Nuclear Information System (INIS)

    Two radionuclides were measured in surface sediment samples taken from geographically distributed sections of Manila Bay, namely cesium-137 (137Cs) and lead-210 (210Pb). Results indicated a noticeable change in the radioactivity concentration levels in sediments collected in 2005 and 2010, with a median concentration of 1.0 and 2.64 Bq kg-1, respectively. Higher levels of 137Cs radioactivity were measured in the northern and inner portion of the bay adjacent to major river systems, agricultural and highly industrialized urban areas. 137Cs isotope increased in activity in most of the samples especially in the northwestern areas of Bataan and Pampanga with five times more than the activity from the first sampling measurements. Nevertheless, radioactivity concentrations observed in surface sediments along the bay are within the range of radioactivity in several areas monitored in the Northern Hemisphere. The country has been frequented by tropical cyclones and storms that have caused erosion, which may have introduced elevated material input in the bay. In addition, wind-driven circulation especially in the shallower areas of the bay is a possibility for the substantial sediment movement and accumulation along this coast. Conversely, areas with higher 137Cs have lower values of 210Pb. In an undisturbed environment, 210Pb deposition values are assumed nearly constant. Hence, changes in the radioactivity concentration levels of these radionuclides can be an indicator of pollution input from land-based sources, sediment movement and reworking in the coastal areas. At present, there is very limited information on the radioactivity level of various radioisotopes in Manila Bay.The data obtained are benchmark values against which changes that will be occurring in the bay can be assessed. (author)

  5. Transport of 137Cs to the Southern Hemisphere in an ocean general circulation model

    Science.gov (United States)

    Tsumune, Daisuke; Aoyama, Michio; Hirose, Katsumi; Bryan, Frank O.; Lindsay, Keith; Danabasoglu, Gokhan

    2011-04-01

    137Cs originating from global fallout is transported into the ocean interior by advection and diffusion, and the 137Cs concentration is reduced by radioactive decay. 137Cs concentrations in the global ocean can be simulated by global integration of the coarse-resolution Parallel Ocean Program to understand the mechanism of material transport in the ocean. We investigated the transport mechanism of 137Cs to the Southern Hemisphere using an ocean general circulation model (OGCM) and compared the simulated results with observations of 137Cs concentrations in the Southern Hemisphere. 137Cs was deposited on the ocean surface mainly as global fallout originating from atmospheric nuclear weapons testing since 1945, and the global distribution of cumulative 137Cs deposition has been reconstructed from global measurements of 137Cs in rain, seawater, and soil. We estimated the global distribution of 137Cs deposition from 1945 to 2003 using these distribution data, 137Cs deposition data observed at the Meteorological Research Institute, Tsukuba, Japan, from 1958 to 2003, and 137Cs deposition data for 1945-1957 estimated from ice-core data. We compared the simulated results with 137Cs sections from the South Pacific, Indian, and South Atlantic Oceans obtained during the BEAGLE2003 cruise in 2003. The simulated 137Cs sections were in good agreement with the observations, except for the effects of mesoscale eddies, which not be simulated by the model because of its coarse resolution. OGCMs can simulate the general pattern of 137Cs distribution in the world’s oceans and improve our understanding of the transport mechanism leading to those 137Cs distributions on a time scale of several decades. The model simulation results suggest that the 137Cs deposited in the North Pacific advected to the South Pacific and Indian Ocean, and then to the South Atlantic over about four decades. The North Pacific is thus an important source area of 137Cs to the Southern Hemisphere.

  6. Electric fields and plasma waves resulting from a barium injection experiment

    International Nuclear Information System (INIS)

    A shaped-charge, barium plasma injection experiment was performed in June 1976 from the DOE Kauai test facility. The rocket payload contained seven shaped charges, a sevenfold larger package than the typical payloads employed in previous barium plasma injections conducted in this program. An attitude control system oriented the injection perpendicular to the local geomagnetic field. The injection altitude was 450 km. The second-stage motor section contained a payload to measure dc and ac electric fields using a 5-m-long, tip-to-tip dual spherical probe antenna. The ac electric field frequency response was from 100 Hz to 12 kHz. The dc channel responds up to 160 Hz. Shortly after the detonation, the dc electric field was parallel to the geomagnetic field. A few seconds later the measured electric field was the v x B field induced by the motion of the antenna through the plasma. A variety of plasma waves were detected for approximately 20 s following the injection. The initial impulse in the dc channel was measured to be 115 mV/m. The injection generated barium cyclotron waves at 3.4, 7.2, and 10.6 Hz. The barium gyrofrequency at the altitude of the injection was 3.3 Hz. The initial amplitude at 3.4 Hz was 25 mV/m peak-to-peak. These waves were evident in the data for approximately 6 s. Between 3 and 8 after the explosion, band-limited noise was intermittently present between 1.6 and 3.2 kHz. These emissions were lower-hybrid-resonance emissions in a barium plasma. The instability responsible for these emissions is tentatively identified as the modified two-stream instability. Wide-band noise with a decreasing intensity as a function of frequency in the band from 100 Hz to 5 kHz was present from 4 to 30 s following the explosion. The intensity maximized when the antenna was most nearly parallel to the geomagnetic field. This suggests that the waves were ion acoustic waves. Highly structured emission occurred between 500 Hz for several seconds after the explosion

  7. Mobility and fluorescence of barium ions in xenon gas for the exo experiment

    Science.gov (United States)

    Benitez Medina, Julio Cesar

    The Enriched Xenon Observatory (EXO) is an experiment which aims to observe the neutrinoless double beta decay of 136Xe. The measurement of this decay would give information about the absolute neutrino mass and whether or not the neutrino is its own antiparticle. Since this is a very rare decay, the ability to reject background events by detecting the barium ion daughter from the double beta decay would be a major advantage. EXO is currently operating a detector with 200 kg of enriched liquid xenon, and there are plans to build a ton scale xenon detector. Measurements of the purity of liquid xenon in our liquid xenon test cell are reported. These results are relevant to the research on detection of single barium ions by our research group at Colorado State University. Details of the operation of the purity monitor are described. The effects of using a purifier, recirculation and laser ablation on the purity of liquid xenon are discussed. Mobility measurements of barium in xenon gas are reported for the first time. The variation of mobility with xenon gas pressure suggests that a significant fraction of molecular ions are formed when barium ions interact with xenon gas at high pressures. The measured mobility of Ba+ in Xe gas at different pressures is compared with the predicted theoretical value, and deviations are explained by a model that describes the fraction of molecular ions in Xe gas as a function of pressure. The results are useful for the analysis of experiments of fluorescence of Ba+ in xenon gas. It is also important to know the mobility of the ions in order to calculate the time they interact with an excitation laser in fluorescence experiments and in proposed 136 Ba+ daughter detection schemes. This thesis presents results of detection of laser induced fluorescence of Ba+ ions in Xe gas. Measurements of the pressure broadening of the excitation spectra of Ba+ in xenon gas are presented. Nonradiative decays due to gas collisions and optical pumping

  8. Contribution of Asian dust to atmospheric deposition of radioactive cesium ((137)Cs).

    Science.gov (United States)

    Fukuyama, Taijiro; Fujiwara, Hideshi

    2008-11-01

    Both Asian dust (kosa) transported from the East Asian continent and locally suspended dust near monitoring sites contribute to the observed atmospheric deposition of (137)Cs in Japan. To estimate the relative contribution of these dust phenomena to the total (137)Cs deposition, we monitored weekly deposition of mineral particles and (137)Cs in spring. Deposition of (137)Cs from a single Asian dust event was 62.3 mBq m(-2) and accounted for 67% of the total (137)Cs deposition during the entire monitoring period. Furthermore, we found high (137)Cs specific activity in the Asian dust deposition sample. Although local dust events contributed to (137)Cs deposition, their contribution was considerably smaller than that of Asian dust. We conclude that the primary source of atmospheric (137)Cs in Japan is dust transported from the East Asian continent.

  9. Distribution of 137Cs radionuclide in industrial wastes effluents of Gresik, East Java, Indonesia

    International Nuclear Information System (INIS)

    The distribution of anthropogenic radionuclides 137Cs was measured from industrial waste effluent of Gresik to Gresik Sea in east Java, Indonesia. The activity of 37Cs detected at all stations was much lower than in northeast Japan both before and after NPP Fukushima accident. This indicated that in Gresik industrials waste did not consist of 137Cs. The lowest activity 137Cs occurred at the station nearest to the industrial waste effluent that contained some particle ions that were able to scavenge 137Cs and then precipate this radionuclide. Furthermore, the greatest 137Cs occurred at the station that has high current speeds that stirred up sediment to release 137Cs in seawater as a secondary source. The lowest salinity did not effect on the activity of 137Cs even though the lowest salinity and activity 137Cs occurred at the same station. (author)

  10. Note on Two Types of Contamination of Human Beings by Caesium-137

    International Nuclear Information System (INIS)

    The authors present an elimination curve for a case of occupational contamination by caesium-137. They also show how the caesium-137 body burden varied during 1963 in a group of persons who did not undergo occupational exposure. (author)

  11. Distribution of 137Cs Radionuclide in Industrial Wastes Effluents of Gresik, East Java, Indonesia

    Directory of Open Access Journals (Sweden)

    Muslim

    2015-04-01

    Full Text Available The distribution of anthropogenic radionuclides 137Cs was measured from industrial waste effluent of Gresik to Gresik Sea in east Java, Indonesia. The activity of 37Cs detected at all stations was much lower than in northeast Japan both before and after NPP Fukushima accident. This indicated that in Gresik industrials waste did not consist of 137Cs. The lowest activity 137Cs occurred at the station nearest to the industrial waste effluent that contained some particle ions that were able to scavenge 137Cs and then precipate this radionuclide. Furthermore, the greatest 137Cs occured at the station that has high current speeds that stirred up sediment to release 137Cs in seawater as a secondary source. The lowest salinity did not effect on the activity of 137Cs even though the lowest salinity and activity 137Cs occured at the same station

  12. Behaviour of 137Cs in the Boreal forest ecosystem of central Sweden

    International Nuclear Information System (INIS)

    Behaviour of Chernobyl fallout 137Cs in a coniferous forest ecosystem in central Sweden was investigated between 1990 and 1994. Results demonstrated that forest soil belongs to nutrient deficient type, and deposited fallout 137Cs from Chernobyl nuclear accident (CNA) was retained (85%) in the upper 5 cm of humic forest soil layer, with a venial migration deeper into soil profile. No correlation between forest soil exchangeable and total potassium (K+) and 137Cs transfer parameters was observed. However, addition of K+, found to efficiently reduce 137Cs uptake by sheep's fescue and the addition of stable caesium (133Cs+) enhanced it. The addition of ammonium (NH4+) was slightly stimulating the uptake of 137Cs by sheep's fescue in the first cut only. Field plants showed a considerably reduction in their 137Cs activity concentrations. Relative to their 137Cs levels of 1986-89, a little reduction in heather (16%) occurred eight years after CNA. In contrast the reductions in lingonberry and bilberry were 87% and 68%, respectively. Three fractions of forest soil bound 137Cs were observed due to sequential extraction procedure (SEP). The first, is easily extractable 137Cs fraction (F1+F2), it comprises 22% of total forest soil 137Cs inventory in the upper 5 cm layer. The second, is soil organically and biologically bound 137Cs (F3+F4) comprises about 30% of soil bound 137Cs. This fraction might be accounted for long-term soil available 137Cs for plant uptake after bio-degradation processes by soil microorganisms. The third, is the residual fraction (F5), it comprises more than 35% of total forest soil 137Cs inventory, and may be associated with soil components which are probably of organic nature. Sorption of 137Cs by zeolite (Mordenite) revealed that soil bound 137Cs is to some extent more mobile in forest soils with high OM% and low pH than those with low OM%. 99 refs

  13. 21 CFR 137.290 - Self-rising yellow corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Self-rising yellow corn meal. 137.290 Section 137... Cereal Flours and Related Products § 137.290 Self-rising yellow corn meal. Self-rising yellow corn meal conforms to the definition and standard of identity prescribed by § 137.270 for self-rising white corn...

  14. Body concentration of caesium-137 in patients from Western Isles of Scotland.

    OpenAIRE

    Isles, C G; Robertson, I.; MacLeod, J A; Preston, T; East, B W; Hole, D J; Lever, A. F.

    1991-01-01

    OBJECTIVES--To compare caesium-137 concentrations in patients from the Western Isles Health Board, Glasgow area, and other parts of the Scottish mainland, and to investigate the source of 137Cs in patients from the Western Isles. DESIGN--Study of hypertensive patients having electrolyte concentrations measured, including 137Cs. Interview by questionnaire of island subjects about intake of foods likely to contain radiocaesium and the source of these foods. Measurement of 137Cs and 134Cs in foo...

  15. 33 CFR 137.50 - Reviews of historical sources of information.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Reviews of historical sources of information. 137.50 Section 137.50 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Practices § 137.50 Reviews of historical sources of information. (a) Historical documents and records...

  16. Regularity of the Cs 137 absorption by hydrolyzed lignin from water solution

    International Nuclear Information System (INIS)

    The kinetics and equilibrium of the Cs 137 sorption by hydrolyzed lignin have been studied. The optimal conditions of the hydrolyzed lignin using as a sorbent for the Cs 137 sorption have been defined. It has been shown that K-monoform of hydrolyzed lignin is a promising sorbent for Cs 137. (authors)

  17. 21 CFR 137.270 - Self-rising white corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Self-rising white corn meal. 137.270 Section 137... Cereal Flours and Related Products § 137.270 Self-rising white corn meal. (a) Self-rising white corn meal is an intimate mixture of white corn meal, sodium bicarbonate, and one or both of the...

  18. 42 CFR 137.337 - What funding must the Secretary provide in a construction project agreement?

    Science.gov (United States)

    2010-10-01

    ... construction project agreement? 137.337 Section 137.337 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF...-GOVERNANCE Construction Project Assumption Process § 137.337 What funding must the Secretary provide in a construction project agreement? The Secretary must provide funding for a construction project agreement...

  19. 42 CFR 137.327 - May multiple projects be included in a single construction project agreement?

    Science.gov (United States)

    2010-10-01

    ... construction project agreement? 137.327 Section 137.327 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF...-GOVERNANCE Construction Project Assumption Process § 137.327 May multiple projects be included in a single construction project agreement? Yes, a Self-Governance Tribe may include multiple projects in a...

  20. 33 CFR 137.60 - Reviews of Federal, State, tribal, and local government records.

    Science.gov (United States)

    2010-07-01

    ..., and local government records. 137.60 Section 137.60 Navigation and Navigable Waters COAST GUARD... DEFENSE Standards and Practices § 137.60 Reviews of Federal, State, tribal, and local government records. (a) Federal, State, tribal, and local government records or databases of government records of...

  1. 42 CFR 137.32 - Is a compact required to participate in self-governance?

    Science.gov (United States)

    2010-10-01

    ...-governance? 137.32 Section 137.32 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES INDIAN HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES TRIBAL SELF-GOVERNANCE Self-Governance compact § 137.32 Is a compact required to participate in self-governance? Yes, Tribes must have...

  2. 47 CFR 101.137 - Interconnection of private operational fixed point-to-point microwave stations.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Interconnection of private operational fixed point-to-point microwave stations. 101.137 Section 101.137 Telecommunication FEDERAL COMMUNICATIONS....137 Interconnection of private operational fixed point-to-point microwave stations....

  3. Fractionation of caesium (137Cs) in coniferous forest soil in central Sweden

    International Nuclear Information System (INIS)

    Sequential extraction procedure (SEP) was applied for fractionation of Chernobyl fallout 137Cs bound onto soils of a coniferous forest ecosystem located in central Sweden. Results of sequentially extracted 137Cs fractions demonstrated that 8% (mean value) of the total deposited 137Cs was water soluble (F1) and 13% was NH4OAc extractable (F2). Oxidation of F2 residuals by H2O2 led to a release of 15% of soil-bound 137Cs (F3). Acid digestion of F3 residuals showed a possibility of releasing an extra amount of soil-bound 137Cs, 22% of the total soil 137Cs inventory (F4). These two fractions (F3 and F4) include strongly bound 137Cs that seems to require longer biodegradation processes by soil microflora and microfauna before becoming available for uptake by plants and fungi. More than 37% of the total soil 137Cs inventory was bound onto soil residuals in a non-extractable form that includes slowly degradable organic matter and other soil residual compartments. The distribution coefficient (Kd) was rather low and shows an inverse relation with the increase of percentage of soil organic matter, which indicates a week binding of 137Cs onto forest soil. In contrast, chemical fractionation of soil bound 137Cs showed a substantial fraction of 137Cs was strongly bound onto soil as organically bound 137Cs. Apparently, the binding processes of radiocaesium onto forest soil seems to be time dependent

  4. 46 CFR 108.137 - Bulkhead and deck separations of accommodation spaces.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Bulkhead and deck separations of accommodation spaces. 108.137 Section 108.137 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Structural Fire Protection § 108.137 Bulkhead and deck separations...

  5. 31 CFR 103.137 - Anti-money laundering programs for insurance companies.

    Science.gov (United States)

    2010-07-01

    ... training by another insurance company or by a competent third party with respect to the covered products... insurance companies. 103.137 Section 103.137 Money and Finance: Treasury Regulations Relating to Money and... Programs Anti-Money Laundering Programs § 103.137 Anti-money laundering programs for insurance...

  6. Bioremoval of Am-241 and Cs-137 from liquid radioactive wasters by bacterial consortiums; Biorremocao de Am-241 e Cs-137 de rejeitos radioativos liquidos por consorcios bacterianos

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Rafael Vicente de Padua; Lima, Josenilson B. de; Gomes, Mirella C.; Borba, Tania R.; Bellini, Maria Helena; Marumo, Julio Takehiro; Sakata, Solange Kazumi, E-mail: rpadua@ipen.b, E-mail: sksakata@ipen.b, E-mail: jblima@ipen.b, E-mail: mbmarumo@ipen.b, E-mail: jtmarumo@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-10-26

    This paper evaluates the capacity of two bacterial consortiums of impacted areas in removing the Am-241 and Cs-137 from liquid radioactive wastes.The experiments indicated that the two study consortiums were able to remove 100% of the Cs-137 and Am-241 presents in the waste from 4 days of contact. These results suggest that the bio removal with the selected consortiums, can be a viable technique for the treatment of radioactive wastes containing Am-241 and Cs-137

  7. Bioaccumulation of Cs-137 and Co-57 by marine phytoplankton

    Energy Technology Data Exchange (ETDEWEB)

    Heldal, H.E. [Inst. of Marine Research, Bergen (Norway); Stupakoff, I.; Fisher, N.S. [State Univ. of New York, Marine Sciences Research Center, Stone Brook, NY (United States)

    1999-11-01

    Under controlled laboratory conditions we have examined the bioaccumulation of Cs-137 and Co-57 in three prymnesiophytes, the coccolithophorid Emiliania huxleyi and the non-calcareous species Isochrysis galbana and Phaeocystis globosa, and two diatoms Skeletonema costatum and Thalassiosira pseudonana. We measured uptake in growing and non-growing cells, and determined concentration factors on both volume and dry weight basis. For Co-57 uptake in non-growing cells, volume concentration factors (VCF) at equilibrium ranged from 0.2{sup *}10{sup 3} for Emiliana huxleyi to 4{sup *}10{sup 3} for the diatom Thalassiosira pseudonana. For Cs-137 uptake in non-growing cells the VCFs were close to zero. The results suggest that, in contrast to Co, the cycling and bioaccumulation in animals of Cs in marine systems is unlikely to be affected by primary producers. (au)

  8. Marine dispersion of caesium 137 released from Sellafield and Chernobyl

    Science.gov (United States)

    Prandle, D.; Beechey, J.

    1991-09-01

    This modelling study examines the dispersion within the shelf seas surrounding the UK, of 137Cs discharged from Sellafield between 1969 and 1988 together with the atmospheric deposition following Chernobyl (April 1986). The close agreement obtained between computed and observed distributions lends confidence to estimates of flushing times-fundamental parameters in determining pollutant concentrations. Moreover, this study confirms, to first-order, the estimates of Chernobyl fall-out provided by atmospheric dispersion models.

  9. Uncertainty in the modelling of 137Cs turnover in lakes

    International Nuclear Information System (INIS)

    In the context of the IAEA-CEC co-ordinated research programme on Validation of Environmental Model Predictions (VAMP), a generic model for lake ecosystems has been tested under a variety of environmental conditions. The main emphasis has been placed on predicting the levels of 137Cs in water and predatory fish, which are of most concern from a radiological point of view. 2 figs

  10. Study on accumulation of 137Cs in aquatic organisms

    Institute of Scientific and Technical Information of China (English)

    FengDing-Hua; CheungT

    1998-01-01

    The organisms were cultivated for 7d in well water contaminated with 137Cs,The experimental results show that the accumulation level of tissues of carassius auratus had the order of gill>viscera>epidermis(including scales)>bone(including head and tail)>flesh.The concentration capability of them had the order of shrimp>carassius auratus>ophiocephalus argus,The concentration factors(CF) of shrimp was 12.6 times of that of ophiocephalus argus.

  11. Effect of heat treatment on the phase composition, structure and magnetic properties of M-type barium hexaferrite

    International Nuclear Information System (INIS)

    Effect of the heat treatment of carbonate-hydroxide precipitates on the phase composition, structure and magnetic properties of M-type barium hexaferrite has been investigated using the Mőssbauer spectroscopy, X-ray phase analysis and magnetic measurements. The distribution of Fe3+ ions over structural sites of barium hexaferrite with different degree of ferritizations has been defined. The conditions of single-domain behavior of barium hexaferrite nanoparticles in the magnetic field have been discussed. Obtained results explain the formation of magnetic structure during the synthesis of barium hexaferrite. This information could further be used for optimizing conditions for synthesis of nanosized barium hexaferrite with high-level properties. - Highlights: • In the T=973–1273 K range, BaFe12O19 (BHF) phase are formed from precipitates. • Fe3+ ions prefer to occupy 12k,2a,2b (at 1073 K) and 4f1,4f2 (at 1273 K) sites. • The most favorable magnetic structure for high Ms forms at T=1073 K. • The presence of 5–10% of α-Fe2O3 phase can improve magnetic properties of BHF

  12. High-Jc YBCO films using precursors with barium concentration gradient in film thickness by TFA-MOD process

    International Nuclear Information System (INIS)

    YBa2Cu3O7-δ (YBCO) films were grown by using precursor films with barium concentration gradient in film thickness by an advanced metal organic deposition process using trifluoroacetates (TFA-MOD). We have reported previously that a lot of non-reacted particles such as Y- and Cu-oxides were remained for the YBCO film surface grown by the precursors using a starting solution with barium-poor (cation ratio as Y:Ba:Cu 1:1.5:3). Then, the barium concentration was increased in the film surface to complete the reaction among these Y and Cu residues and Ba and to increase the Y123 growth thickness for realizing higher Jc performance. Transmission electron microscopy (TEM) observation showed the increase of film thickness of YBCO grown by the precursors with barium concentration gradient in film thickness, indicating that the reaction between these Y and Cu-oxides and Ba proceeded to form Y123 phase. Consequently, higher Jc was obtained for the YBCO film by the precursors mentioned above than that of the YBCO film by the precursors with a constant concentration. Effects of barium concentration gradient in the precursors on the superconducting properties and microstructures in the YBCO film were discussed.

  13. A study of the Arrhenius behavior of the co-precipitation of radium, barium and strontium sulfate

    International Nuclear Information System (INIS)

    Co-precipitation of radium, barium and strontium is an important process in many contexts, such as uranium mining, oil extraction and in the safety assessment of a final repository for used nuclear fuel. Co-precipitation to a solid solution is possible since radium, barium and strontium act as chemical analogues. In this work the co-precipitation of radium, barium and strontium was studied and the kinetic behavior of the co-precipitation process was investigated. It was shown that radium, barium and strontium co-precipitate congruently and that the precipitation followed an Arrhenius behavior and the Arrhenius parameters for the systems was determined. When studying the differences of the Arrhenius constants by using a student t test (95 % confidence interval) it was observed that the only significant difference in the activation energy, Ea, is between radium and barium and between radium and strontium respectively, the pure strontium having the larger activation energy in comparison. This is most likely coupled to the metal ion size; since the hydration waters are more strongly bound, which leads to them having a slower exchange rate, which in turn effects the rate of co-precipitation to the metal these reactions will be slower. (author)

  14. Evaluation of modelling body burden of Cs-137

    International Nuclear Information System (INIS)

    Within the IAEA/CEC VAMP-program one working group studied the precision in dose assessment models when calculating body burden of 137Cs as a result of exposure through multiple exposure pathways. One scenario used data from southern Finland regarding contamination of various media due to the fallout from the Chernobyl accident. In this study, a time dependent multiple exposure pathway model was constructed based on compartment theory. Uncertainties in model responses due to uncertainties in input parameter values were studied. The initial predictions for body burden were good, within a factor of 2 of the observed, while the time dynamics of levels in milk and meat did not agree satisfactorily. Some results, nevertheless, showed good agreement with observations due to compensatory effects. After disclosure of additional observational data, major reasons for mispredictions were identified as lack of consideration of time dependence of fixation of 137Cs in soils, and the selection of parameter values. When correction of this was made, a close agreement between predictions and observations was obtained. This study shows that the dose contribution due to 137Cs in food products from the seminatural environment is important for long-term exposure to man. The evaluation provided a basis for improvements of crucial parts in the model. 14 refs, 18 figs, 8 tabs

  15. Quality assurance of {sup 137}Cs Photons for Vivo Mouse Irradiation System

    Energy Technology Data Exchange (ETDEWEB)

    Noh, S. J. [Inje Univ., Kimhae (Korea, Republic of); Kim, H. J.; Jeong, D. H.; Yang, K. M.; Son, T. G.; Kang, Y. R. [Dongnam Institute of Radiological and Medical Sciences, Busan (Korea, Republic of); Shin, S. G.; Kye, Y. U. [Pohang University of Science and Technology, Pohang (Korea, Republic of)

    2014-10-15

    The multi-purpose irradiation apparatus using a {sup 137}Cs, which can be used for the blood test, can be affected by the other components of the experiments such as the size and shape of the beaker and the maximum variation of more than 35% has been reported. The mount of the absorbed dose is determined by the distance between irradiation target and the source and the irradiation time with the irradiator (Gamma Irradiator, Chiyoda Technol Co, Japan) for this experiment. The low-dose irradiation has been used in this study is advantageous for irradiating the cell culture vessel or the small animal. However, radiation is performed by placing the 3-5 mice in each mouse cage (polycarbonate cage). In this case, overlapping often happens to the target during irradiation. Irradiating without considering the geometrical aspect of the irradiation device can occur as well. To solve the problems, the mouse apartment with the 45 mouse cages is built and the device is assessed by being compared with the conventional method in 2 different ways. Firstly, the glass dosimeters were inserted into the head and the body of the lab mice for 2 methods. Secondly, MCNP simulation was performed for absorbed dose and air kerma measurements in each mouse apartment chamber. In this study, the system that allows the accurate irradiation using the {sup 137}Cs gamma irradiator mainly used in Radiation Biology was developed and the accuracy of the system has been confirmed by the experiments. The dose delivery using the conventional system had the variation of 42% at most whereas the variation was less than 6% for the mouse apartment. From the MCNP simulation, the difference between each chamber was less than 0.1% and 0.4% for the air kerma and the absorbed dose respectively. Considering the statistical error of MCNP and the assumption from the simulation, the accuracy of the simulation was matched well with the measurements with the glass dosimeters.

  16. Focusing and sustaining the antitumor CTL effector killer response by agonist anti-CD137 mAb

    Science.gov (United States)

    Weigelin, Bettina; Bolaños, Elixabet; Teijeira, Alvaro; Martinez-Forero, Ivan; Labiano, Sara; Azpilikueta, Arantza; Morales-Kastresana, Aizea; Quetglas, José I.; Wagena, Esther; Sánchez-Paulete, Alfonso Rodríguez; Chen, Lieping; Friedl, Peter; Melero, Ignacio

    2015-01-01

    Cancer immunotherapy is undergoing significant progress due to recent clinical successes by refined adoptive T-cell transfer and immunostimulatory monoclonal Ab (mAbs). B16F10-derived OVA-expressing mouse melanomas resist curative immunotherapy with either adoptive transfer of activated anti-OVA OT1 CTLs or agonist anti-CD137 (4-1BB) mAb. However, when acting in synergistic combination, these treatments consistently achieve tumor eradication. Tumor-infiltrating lymphocytes that accomplish tumor rejection exhibit enhanced effector functions in both transferred OT-1 and endogenous cytotoxic T lymphocytes (CTLs). This is consistent with higher levels of expression of eomesodermin in transferred and endogenous CTLs and with intravital live-cell two-photon microscopy evidence for more efficacious CTL-mediated tumor cell killing. Anti-CD137 mAb treatment resulted in prolonged intratumor persistence of the OT1 CTL-effector cells and improved function with focused and confined interaction kinetics of OT-1 CTL with target cells and increased apoptosis induction lasting up to six days postadoptive transfer. The synergy of adoptive T-cell therapy and agonist anti-CD137 mAb thus results from in vivo enhancement and sustainment of effector functions. PMID:26034288

  17. Dissolution behavior of 137Cs absorbed on the green tea leaves

    International Nuclear Information System (INIS)

    The green tea leaf was dipped in the 137CsCl solution to elucidate the dissolution behavior of 137Cs. The IP observation showed that 137Cs was not uniformly adsorbed on the tea leaf, even if the tea leaf was dipped in the homogeneous solution. The activation energy of 137Cs dissolution was estimated to be 0.045 eV, indicating that most of 137Cs would exist as the adsorbed state. The dissolution behaviors as a function of cesium and potassium concentrations and pH, were also studied. (author)

  18. Dissolution behavior of 137Cs absorbed on the green tea leaves

    International Nuclear Information System (INIS)

    The green tea leaves was dipped in the 137CsCl solution to elucidate the dissolution behavior of 137Cs contaminated on the green tea leaves. It was found that the amount of 137Cs dissolved into tea water was controlled by the temperature of water, and the activation energy of 137Cs dissolution was estimated to be 0.045 eV, indicating that most of 137Cs would exist as the adsorbed state. In addition, the dissolution behavior was controlled by the concentration of stable Cs dissolved in water, although no large correlation with pH was observed. (author)

  19. Proceedings of the national workshop on the use of 137Cs to measure erosion

    International Nuclear Information System (INIS)

    The workshop was concerned with the use and development of Cs-137 techniques of measuring erosion. The overall outcome of the workshop was a view that it is inappropriate at this time to conduct a comprehensive national assessment of soil erosion using the Caesium-137 technique, but it is appropriate to conduct a reconnaissance survey which would establish/confirm reference levels of Cs137 deposition across Australia, establish, at a statistically viable level, the capability to confirm at least large differences in Cs137 concentration, and build up a more comprehensive picture of Cs137 and its association with soil movement in the Australian landscape

  20. Experimental contamination of pink shrimps by caesium 137; Contamination experimentale de crevettes roses par le cesium 137

    Energy Technology Data Exchange (ETDEWEB)

    Ancellin, J.; Michon, G.; Vilquin, A. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1965-07-01

    The authors describe first of all the technique used for the determination of cesium 137 concentration factors in the pink shrimp (Leander Serratus Pennant). Experiments over three months have shown that the specific activity of the shrimps becomes stable between the thirtieth and the fortieth day. The concentration factors then have values between 30 and 40. These results are similar to those obtained by other authors. (authors) [French] Les auteurs decrivent tout d'abord la technique utilisee pour la determination des facteurs de concentration du Cesium 137 chez la crevette rose (Leander Serratus Pennant). Le resultat des experimentations menees pendant trois mois montre que l'activite specifique des crevettes se stabilise entre le trentieme et le quarantieme jour. Les facteurs de concentration se situent alors entre 30 et 40, Ces donnees sont comparables a celles obtenues par d'autres auteurs. (auteur)

  1. Divergence of Cs-137 sources fluence used in brachytherapy; Divergencia da fluencia de fontes de Cs-137 usadas em braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    Vianello, E.A.; Almeida, C.E. de [Laboratorio de Ciencias Radiologicas- LCR-DBB (UERJ). R. Sao Francisco Xavier, 524- Pav. HLC, sala 136 terreo- CEP 20.550- 013. Rio de Janeiro (Brazil)

    1998-12-31

    In this work the experimental determination of correction factor for fluence divergence (kln) of linear Cs-137 sources CDCS J4, with Farmer ionization chamber model 2571 in a central and perpendicular plan to source axis, for distances range from 1 to 7 cm., has been presented. The experimental results were compared to calculating by Kondo and Randolph (1960) isotropic theory and Bielajew (1990) anisotropic theory. (Author)

  2. Bioaccumulation of cesium-137 in yellow bullhead catfish (Ameiurus natalis) inhabiting an abandoned nuclear reactor reservoir

    International Nuclear Information System (INIS)

    Bioaccumulation of 137Cs was investigated in yellow bullhead catfish (Ameiurus natalis) inhabiting an abandoned reactor reservoir, Pond B, Savannah River Site, Barnwell Co., South Carolina. The authors collected fish by trap-netting, and determined ages from pectoral spines. Muscle and other tissues were assayed for 137Cs by NaI-scintillation. Music 137Cs was unrelated to sex or mass of fish, but was related to age. Examination of least-squares means suggested that 137Cs in muscle increased up to about age 3, but did not increase with greater age. A modified Richards model showed equilibrium 137Cs concentration in muscle was acquired in approximately 2.4 years. Growth differed between sexes and the time to asymptotic body mass was longer than the time to attain equilibrium 137Cs concentration. Males attained an asymptotic mass of 577 g in approximately 6.3 years; females attained an asymptotic mass of 438 g in approximately 5.9 years. The cumulative 137Cs burden of the population was 4.9 x 106 Bq, representing 137Cs inventory of the reservoir. Concentration of 137Cs varied among tissues with gill and muscle the lowest and highest. Concentration of 137Cs in ovaries declined with increasing ovary mass. Until equilibrium is attained in these fish, 137Cs concentration is directly related to increasing age rather than size

  3. Barium meal follow through with pneumocolon: Screening test for chronic bowel pain

    Institute of Scientific and Technical Information of China (English)

    Sandeep Nijhawan; Saket Kumpawat; P Mallikarjun; RP Bansal; Dinesh Singla; Prachis Ashdhir; Amit Mathur; Ramesh Roop Rai

    2008-01-01

    AIM:To study the sensitivity,specificity and cost effectiveness of barium meal follow through with pneumocolon (BMFTP) used as a screening modality for patients with chronic abdominal pain of luminal origin in developing countries.METHODS:Fifty patients attending the Gastroenterology Unit,SMS Hospital,whose clinical evaluation revealed chronic abdominal pain of bowel origin were included in the study.After routine testing,BMFT,BMFTP,contrast enhanced computed tomography (CECT) of the abdomen,barium enema and colonoscopy were performed.The sensitivity,specificity and cost effectiveness of these imaging modalities in the detection of small and/or large bowel lesions were compared.RESULTS:Out of fifty patients,structural pathology was found in ten.Nine out of these ten patients had small bowel involvement while seven had colonic involvement alone or in combination with small bowel involvement.The sensitivity of BMFTP was 100% compared to 88.89% with BMFT when detecting small bowel involvement (BMFTP detected one additional patient with ileocecal involvement).The sensitivity and specificity of BMFTP for the detection of colonic pathology were 85.71% and 95.35%(41/43),respectively.Screening a patient with chronic abdominal pain (bowel origin) using a combination of BMFT and barium enema cost significantly more than BMFTP while their sensitivity was almost comparable.CONCLUSION:BMFTP should be included in the investigative workup of patients with chronic abdominal pain of luminal origin,where either multiple sites (small and large intestine) of involvement are suspected or the site is unclear on clinical grounds.BMFTP is an economical,quick and comfortable procedure which obviates the need for colonoscopy in the majority of patients.

  4. Microstructure and magnetic properties of Al-doped barium ferrite with sodium citrate as chelate agent

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Daming, E-mail: chendaming1986@gmail.com [State Key Laboratory of Electronic Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Liu, Yingli, E-mail: lyl@uestc.edu.cn [State Key Laboratory of Electronic Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Li, Yuanxun; Yang, Kai; Zhang, Huaiwu [State Key Laboratory of Electronic Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2013-07-15

    In this paper, M-type Al-doped barium ferrites were successfully synthesized using sodium citrate (SC) as the chelate agent by a chemical process complemented by a suitable thermal treatment of the precursor. It was found in TGA/DTA and XRD analysis that the crystallization and formation of single phase BaM had completed before 860 °C. The XRD data also confirmed Al substituting into Fe sites. Meanwhile, it can be seen from the SEM images that the particle size and morphology were not affected by Al doping. However, Al substitution played an important role on the magnetic properties. The saturation magnetization (M{sub s}) of BaAl{sub x}Fe{sub 12−x}O{sub 19} decreased from 51.43 emu/g for the sample with x=0 to 28.32 emu/g at x=1.5. The anisotropy field (H{sub a}), however, increased from 16.21 kOe to 25.01 kOe. In addition, M{sub s} increased with enhancing the ratio of SC/Ba{sup 2+}(molar ratio), reaching a maximum when SC/Ba{sup 2+} was 13. - Highlights: ► Doped barium ferrite was successfully synthesized using sodium citrate as chelate agent. ► Sodium citrate allows the mixing of metal cations in the as-synthesized barium ferrite. ► The radio of Sodium citrate/Ba{sup 2+} pay an important effect on magnetic properties.

  5. Curie temperature and magnetic properties of aluminum doped barium ferrite particles prepared by ball mill method

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Daming [Center for Magnetism and Magnetic Nanostructures, University of Colorado at Colorado Springs, 1420 Austin Bluffs Pkwy, Colorado Springs, Colorado 80918 (United States); College of Materials and Chemical Engineering, Hainan University, Haikou 570228, Hainan (China); Harward, Ian; Baptist, Joshua; Goldman, Sara; Celinski, Zbigniew [Center for Magnetism and Magnetic Nanostructures, University of Colorado at Colorado Springs, 1420 Austin Bluffs Pkwy, Colorado Springs, Colorado 80918 (United States)

    2015-12-01

    Barium ferrite has attracted considerable interest in the fields of permanent magnets and perpendicular magnetic recording due to its strong uniaxial anisotropy and high Curie temperature (T{sub c}). We prepared aluminum doped barium ferrite ceramics (BaAl{sub x}Fe{sub 12−x}O{sub 19}, 0≤x≤6) by the ball mill method. The powder was milled for 96 h, and after forming pellets, annealed for 48 h in air at 1000 °C. The X-ray diffraction (XRD) data show that there are only single hexagonal phases in the samples without any impurity phase. The crystal lattice constants, a and c, were calculated by Cohen's method. Both a and c decrease with increasing x, ranging from 0.588 nm and 2.318 nm to 0.573 nm and 2.294 nm, respectively. A Vibrating Sample Magnetometer (VSM) and Superconducting Quantum Interference Device (SQUID) were used to investigate T{sub c} and magnetic properties of BaFe{sub 12−x}Al{sub x}O{sub 19}. It is found that T{sub c} decreases with increasing x, from 425 °C to 298 °C. It is also found that the saturated magnetization (4πM{sub s}) decreases with increasing x, while the coercivity (H{sub c}) increases with the increase in x. The anisotropy field was also determined from the SQUID measurement. - Highlights: • The Curie temperature and magnetic properties of aluminum doped barium ferrite particles were studied systemically. • The relation between 4πM{sub s} and composition x at 50 K (both experimental value and theoretical calculation) was revealed. • Occupation number for spin up and spin down as a function of temperature was shown. • The relation between 4πM{sub s} and composition x from 50 K to room temperature was revealed.

  6. Hydrothermal Synthesis and Processing of Barium Titanate Nanoparticles Embedded in Polymer Films.

    Science.gov (United States)

    Toomey, Michael D; Gao, Kai; Mendis, Gamini P; Slamovich, Elliott B; Howarter, John A

    2015-12-30

    Barium titanate nanoparticles embedded in flexible polymer films were synthesized using hydrothermal processing methods. The resulting films were characterized with respect to material composition, size distribution of nanoparticles, and spatial location of particles within the polymer film. Synthesis conditions were varied based on the mechanical properties of the polymer films, ratio of polymer to barium titanate precursors, and length of aging time between initial formulations of the solution to final processing of nanoparticles. Block copolymers of poly(styrene-co-maleic anhydride) (SMAh) were used to spatially separate titanium precursors based on specific chemical interactions with the maleic anhydride moiety. However, the glassy nature of this copolymer restricted mobility of the titanium precursors during hydrothermal processing. The addition of rubbery butadiene moieties, through mixing of the SMAh with poly(styrene-butadiene-styrene) (SBS) copolymer, increased the nanoparticle dispersion as a result of greater diffusivity of the titanium precursor via higher mobility of the polymer matrix. Additionally, an aminosilane was used as a means to retard cross-linking in polymer-metalorganic solutions, as the titanium precursor molecules were shown to react and form networks prior to hydrothermal processing. By adding small amounts of competing aminosilane, excessive cross-linking was prevented without significantly impacting the quality and composition of the final barium titanate nanoparticles. X-ray diffraction and X-ray photoelectron spectroscopy were used to verify nanoparticle compositions. Particle sizes within the polymer films were measured to be 108 ± 5 nm, 100 ± 6 nm, and 60 ± 5 nm under different synthetic conditions using electron microscopy. Flexibility of the films was assessed through measurement of the glass transition temperature using dynamic mechanical analysis. Dielectric permittivity was measured using an impedance analyzer. PMID

  7. Intermediate milling energy optimization to enhance the characteristics of barium hexaferrite magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Hodaei, A.; Ataie, A., E-mail: aataie@ut.ac.ir; Mostafavi, E.

    2015-08-15

    Highlights: • Nano-sized BaFe{sub 12}O{sub 19} was successfully synthesized via a solid-state reaction. • Intermediate milling energy was optimized to improve BaFe{sub 12}O{sub 19} properties. • Minimum total energy of 93.7 kJ/g was necessary for formation of BaFe{sub 12}O{sub 19}. • Deviation from the optimum milling energy deteriorates the magnetic properties. - Abstract: Nano-sized barium hexaferrite particles were synthesized by mechanical activation of BaCO{sub 3} and Fe{sub 2}O{sub 3} powders mixture as starting materials. The effects of mechanical milling energy on the phase composition, morphology, thermal behavior and magnetic properties of the samples were systematically investigated by employing X-ray diffractometer, field emission scanning electron microscopy, differential thermal/thermo gravimetry analysis and vibrating sample magnetometer, respectively. The milling energy was calculated at five different levels using collision model. It was found that there is an optimum milling energy value for obtaining barium hexaferrite phase. The results revealed that applying a minimum total milling energy of 93.7 kJ/g was necessary for formation of almost single barium hexaferrite at a relatively low calcination temperature of 800 °C. FESEM micrograph of the above sample exhibited nano-size particles with a mean particle size of 80 nm. Further increase in milling energy leads to dramatic decrease in phase purity as well as magnetic characteristics of the samples. By increasing the milling energy from 93.7 to 671.9 kJ/g, saturation magnetization (M{sub s}) decreased from 22.5 to 0.39 emu/g, and also coercivity (H{sub c}) decreased from 4.28 to 1.46 kOe.

  8. Intermediate milling energy optimization to enhance the characteristics of barium hexaferrite magnetic nanoparticles

    International Nuclear Information System (INIS)

    Highlights: • Nano-sized BaFe12O19 was successfully synthesized via a solid-state reaction. • Intermediate milling energy was optimized to improve BaFe12O19 properties. • Minimum total energy of 93.7 kJ/g was necessary for formation of BaFe12O19. • Deviation from the optimum milling energy deteriorates the magnetic properties. - Abstract: Nano-sized barium hexaferrite particles were synthesized by mechanical activation of BaCO3 and Fe2O3 powders mixture as starting materials. The effects of mechanical milling energy on the phase composition, morphology, thermal behavior and magnetic properties of the samples were systematically investigated by employing X-ray diffractometer, field emission scanning electron microscopy, differential thermal/thermo gravimetry analysis and vibrating sample magnetometer, respectively. The milling energy was calculated at five different levels using collision model. It was found that there is an optimum milling energy value for obtaining barium hexaferrite phase. The results revealed that applying a minimum total milling energy of 93.7 kJ/g was necessary for formation of almost single barium hexaferrite at a relatively low calcination temperature of 800 °C. FESEM micrograph of the above sample exhibited nano-size particles with a mean particle size of 80 nm. Further increase in milling energy leads to dramatic decrease in phase purity as well as magnetic characteristics of the samples. By increasing the milling energy from 93.7 to 671.9 kJ/g, saturation magnetization (Ms) decreased from 22.5 to 0.39 emu/g, and also coercivity (Hc) decreased from 4.28 to 1.46 kOe

  9. Small-scale fluctuations in barium drifts at high latitudes and associated Joule heating effects

    Science.gov (United States)

    Hurd, L. D.; Larsen, M. F.

    2016-01-01

    Most previous estimates of Joule heating rates, especially the contribution of small-scale structure in the high-latitude ionosphere, have been based on incoherent scatter or coherent scatter radar measurements. An alternative estimate can be found from the plasma drifts obtained from ionized barium clouds released from sounding rockets. We have used barium drift data from three experiments to estimate Joule heating rates in the high-latitude E region for different magnetic activity levels. In particular, we are interested in the contribution of small-scale plasma drift fluctuations, corresponding to equivalent electric field fluctuations, to the local Joule heating rate on scales smaller than those typically resolved by radar or other measurements. Since Joule heating is a Lagrangian quantity, the inherently Lagrangian estimates provided by the chemical tracer measurements are a full description of the effects of electric field variance and neutral winds on the heating, differing from the Eulerian estimates of the type provided by ground-based measurements. Results suggest that the small-scale contributions to the heating can be more than a factor of 2 greater than the mean field contribution regardless of geomagnetic conditions, and at times the small-scale contribution is even larger. The high-resolution barium drift measurements, moreover, show that the fine structure in the electric field can be more variable than previous studies have reported for similar conditions. The neutral winds also affect the heating, altering the height-integrated Joule heating rates by as much as 12%, for the cases studied here, and modifying the height distribution of the heating profile as well.

  10. Nanosized barium hexaferrite in novolac phenolic resin as microwave absorber for X-band application

    Energy Technology Data Exchange (ETDEWEB)

    Ozah, S.; Bhattacharyya, N.S., E-mail: nidhisbhatta@gmail.com

    2013-09-15

    Nanosized barium ferrite (BaFe{sub 12}O{sub 19}) with Novolac phenolic resin (NPR) is developed as a magnetic absorber for application in the frequency range 8.2–12.4 GHz. The absorption is studied by modifying the microstructural properties of the ferrite inclusion with annealing temperature and its content in the composite. Transmission electron microscopy and X-ray diffraction pattern confirms the formation of hexagonal structure of barium ferrite. The crystallite size of the barium ferrite particles is in nano-range and increases with annealing temperature. The BaFe{sub 12}O{sub 19}/NPR composite is prepared with different weight percentage of ferrite inclusions. The complex permittivity and complex permeability is measured at X-band and found to increase with annealing temperature and contents of ferrite inclusion. Theoretical study of reflection loss gives that 2 mm absorber samples are showing the best results for X-band application. Reflection loss measurement of the samples shows absorption peak of −24.61 dB at 10.26 GHz for 30 wt%, −28.39 dB at 9.98 GHz for 40 wt% and −37.06 dB at 9.5 GHz for 50 wt% of BaFe{sub 12}O{sub 19} in NPR matrix. - Highlights: • BaFe{sub 12}O{sub 19}/NPR composite is developed as microwave absorbing material. • The maximal absorption is optimized with thickness using TLM. • Calculated reflection loss of 50 wt% for 2 mm thickness is 41.05 dB at 9.95 GHz. • Measured reflection loss of 50 wt% for 2 mm thickness is 37.06 dB at 9.5 GHz.

  11. Curie temperature and magnetic properties of aluminum doped barium ferrite particles prepared by ball mill method

    International Nuclear Information System (INIS)

    Barium ferrite has attracted considerable interest in the fields of permanent magnets and perpendicular magnetic recording due to its strong uniaxial anisotropy and high Curie temperature (Tc). We prepared aluminum doped barium ferrite ceramics (BaAlxFe12−xO19, 0≤x≤6) by the ball mill method. The powder was milled for 96 h, and after forming pellets, annealed for 48 h in air at 1000 °C. The X-ray diffraction (XRD) data show that there are only single hexagonal phases in the samples without any impurity phase. The crystal lattice constants, a and c, were calculated by Cohen's method. Both a and c decrease with increasing x, ranging from 0.588 nm and 2.318 nm to 0.573 nm and 2.294 nm, respectively. A Vibrating Sample Magnetometer (VSM) and Superconducting Quantum Interference Device (SQUID) were used to investigate Tc and magnetic properties of BaFe12−xAlxO19. It is found that Tc decreases with increasing x, from 425 °C to 298 °C. It is also found that the saturated magnetization (4πMs) decreases with increasing x, while the coercivity (Hc) increases with the increase in x. The anisotropy field was also determined from the SQUID measurement. - Highlights: • The Curie temperature and magnetic properties of aluminum doped barium ferrite particles were studied systemically. • The relation between 4πMs and composition x at 50 K (both experimental value and theoretical calculation) was revealed. • Occupation number for spin up and spin down as a function of temperature was shown. • The relation between 4πMs and composition x from 50 K to room temperature was revealed

  12. Caesium-137 in the foodchain lichen-reindeer-man during 1976 to 1978

    International Nuclear Information System (INIS)

    The behaviour of the 137Cs isotope in the subarctic environment has been an object of investigations in this laboratory since 1960. The 137Cs body burden of a group of about 100 Lapps has been determined annually each spring since 1962 using a mobile whole-body counting system accommodated in a truck. In spring 1977, 31 reindeer herders and reindeer herding fishermen residing in Inari were thus measured. In spring 1978, no 137Cs body burden measurements of the Lapps were carried out. Instead, analysis of 137Cs in lichen and reindeer muscle samples was continued in order to check possible changes in the environmental 137Cs level. In this paper 137Cs concentrations in lichen in 1977 and in reindeer muscle in 1977 and 1978 are reported. Using these results the 137Cs body burden of Finnish Lapps is estimated

  13. Relationship between 137Cs concentration and cultivated history on loessial hillslopes

    International Nuclear Information System (INIS)

    There are close linkages between soil loss degree and soil disturbance degree by human. So it is a key problem to know that how human activity affects soil loss. To analyse the correlation of 137Cs loss degree with hillslopes' cultivated histories, the concentrations of 137Cs on different kinds of loessial hillslopes with different cultivated histories, abandoned ages and different patterns of reforestation are studied. The result shows that there is a linear relationship among 137Cs areal concentrations, cultivation ages and slope gradients. the regressive equation is as follows: X=2356.79-22.77 t-35.53 S. Variant coefficient of 137Cs areal concentration is 80.11% among hillslopes with different abandonment ages. It is also deduced that 137Cs areal concentration is affected primarily by abandonment ages of hillslopes. The 137Cs loss rates of hillslopes with different vegetation restoration manners show significant differences, as a whole, autogenic restoration 137Cs area concentrations on hillslopes. (authors)

  14. Synthesis and characterization of highly-ordered barium-strontium titanate nanotube arrays fabricated by sol-gel method

    Institute of Scientific and Technical Information of China (English)

    Chen Yu; Chen Wei; Guo Feng; Li Mei-Ya; Liu Wei; Zhao Xing-Zhong

    2009-01-01

    Highly uniformed barium-strontium titanate nanotube arrays were fabricated using a porous anodic aluminum oxide template from a barium-strontium titanate sol-gel solution. Electron microscope results showed that nanotubes with uniform length and diameter were obtained. The diameters and lengths of these nanotubes were dependent on the pore diameter and the thickness of the applied anodic aluminum oxide template. High resolution transmission electron microscopy and the selected-area electron diffraction pattern investigations demonstrated the perovskite structure and the polycrystaltine of the fabricated barium-strontium titanate nanotubes. The characterization of the electrical and dielectric properties had also been made. Compared to thin film material,the intrinsic leakage current density is almost the same. Besides,at 30 ℃,the dielectric constant and dielectric loss of the fabricated nanotube is 80 and 0.027 at 1 MHz respectively.

  15. Early manifestation of Yersinia colitis demonstrated by the double-contrast barium enema

    Energy Technology Data Exchange (ETDEWEB)

    Aspestrand, F.

    1986-11-01

    A 19-year old female with a bloody, diarrheal illness of acute onset where Crohn's disease primarly was suspected is presented. The double-contrast barium enema revealed multiple, diffusely scattered aphthous erosions of the colonic mucosa: the rectum was scarcely affected. Biopsies taken by endoscopy demonstrated nonspecific inflammatory changes of the mucous membrane. However, routinely taken stool cultures revealed an infectious colitis due to Yersinia enterocolitica. Our case demonstrates the necessity to consider Yersinia enterocolitis in the radiographic differential diagnosis when the diagnosis of Crohn's disease or ulcerative colitis seems obvious.

  16. Spectroscopic studies of Nb- and Hf-doped barium titanate crystals

    International Nuclear Information System (INIS)

    One studied the absorption spectra of barium titanate single crystals doped with niobium and hafnium, as well as, those of pure BaTiO3 single crystal. One detected peculiarities both under ferro-paraelectric phase transition at 120 deg C and in paraelectric phase within 150-170 deg C. One observed increase of intensity of λmax = 700 nm band within beyond 150-170 deg C range that was adequate to the increase of number of F-centres

  17. EDTA-type Polymer Based on Diazacrown Ether as the Solubilizer of Barium Sulfate to Water

    Institute of Scientific and Technical Information of China (English)

    Bo ZHOU; Jian Zhang LI; Chun Hong HE; Sheng Ying QIN

    2005-01-01

    The EDTA dianhydride reacted with diazacrown ethers to obtain the water-soluble EDTA-diazacrown ether polymers 1~3. The effects of crown ether ring in the polymer chains including its cavity size on the solubilization of barium sulfate to water were investigated by comparison with the crown ring-free analogue 4. The result shows that the polymer 2 is the efficient solubilizer of BaSO4 and the highest solubilization efficiency of the BaSO4 to water is up to 72.5%.

  18. Synthesis of Barium Lithium Fluoride Nanocrystals Using Reverse Micelles as Microemulsion

    Institute of Scientific and Technical Information of China (English)

    Rui Nian HUA; De Min XIE; Chun Shan SHI

    2004-01-01

    Barium lithium fluoride nanocrystals were synthesized in cetyltrimethylammonium bromide (CTAB)/ 2-octanol/ water microemulsion systems. The impurity peaks in XRD patterns were not determined. The result of SEM confirmed that the average sizes and shape of the BaLiF3 nanocrystals. The formation of BaLiF3 and particles size were strongly affected by water content. With increasing water content and reaction times, the size of the particle increases. Meanwhile, the solvent was also found to play a key role in the synthesis of the BaLiF3 nanocrystals.

  19. Investigation of thermal evolution of nanodomain structures in nonlinear barium sodium niobate crystals

    Institute of Scientific and Technical Information of China (English)

    S.V.Ivanova

    2008-01-01

    By the 90°elastic light scattering investigation and far field observation in the range of 20-800℃,the relation between behavior of light scattering anomalies and evolution of nanodomain structures in lattice of barium sodium niobate(Ba2NaNb5O15,BSN)crystal was clarified.The correlation between anomalies on the temperature curves of the elastic light scattering intensity and temperature transformations of nanodomains was studied by X-ray and electron microscope methods.Phase transition near 500℃ and movement in field of scattering light could be explained by appearance of a new incommensurate phase.

  20. The ac Stark shifts of the terahertz clock transitions of barium

    Institute of Scientific and Technical Information of China (English)

    余庚华; 耿鹰鸽; 李隆; 周超; 段丞博; 柴瑞鹏; 杨永明

    2015-01-01

    Wavelength-dependent AC Stark shifts and magic wavelengths of the terahertz clock transitions between the metastable triplet states 6s5d 3D1 and 6s5d 3D2 are investigated with considering the optical lattice trapping of barium atoms with the linearly polarized laser. The trap depths and the slopes of light shift difference with distinct magic wave-lengths of the optical lattices are also discussed in detail. Several potentially suitable working points for the optical lattice trapping laser are recommended and selected from these magic wavelengths.