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Sample records for thallium carbonates

  1. Thallium and its contents in Remata carbonate rocks

    Directory of Open Access Journals (Sweden)

    Kondelová Marcela

    1996-09-01

    Full Text Available The article presents at first the list of thallium own minerals and its isomorphic content in other minerals, especially in Slovakian ore deposits. This trace element was found in numerous dolomite-rock samples from Remata massif near Handlová. An interesting level of Tl content was analyzed in nonsilicified rocks; the highest content of Tl (and Ag are along the E – W line of disturbance. The presence of thallium in some limonitic aggregates in close Kremnica-gold deposit indicate any continuous relation. Some similarities to type gold deposits Carlin ( USA are discussed, even if no gold and discrete thallium phases were in Remata determined yet.

  2. L-Tyrosine immobilized on multiwalled carbon nanotubes: A new substrate for thallium separation and speciation using stabilized temperature platform furnace-electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco, Pablo H.; Gil, Raul A. [Departamento de Quimica Analitica, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, P.O. Box 375, 5700 San Luis (Argentina); Instituto de Quimica de San Luis (INQUISAL-CONICET), Chacabuco y Pedernera, CP 5700, San Luis (Argentina); Smichowski, Patricia, E-mail: smichows@cnea.gov.ar [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Rivadavia 1917, CP C1033 AAJ, Ciudad de Buenos Aires (Argentina); Comision Nacional de Energia Atomica, Gerencia Quimica, Av. Gral. Paz 1499, B1650KNA San Martin (Argentina); Polla, Griselda [Comision Nacional de Energia Atomica, Gerencia de Investigacion y Aplicaciones, Av.Gral. Paz 1499, B1650KNA San Martin (Argentina); Martinez, Luis D., E-mail: ldm@unsl.edu.ar [Departamento de Quimica Analitica, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, P.O. Box 375, 5700 San Luis (Argentina); Instituto de Quimica de San Luis (INQUISAL-CONICET), Chacabuco y Pedernera, CP 5700, San Luis (Argentina)

    2009-12-10

    An approach for the separation and determination of inorganic thallium species is described. A new sorbent, L-tyrosine-carbon nanotubes (L-tyr-CNTs), was used and applied to the analysis of tap water samples. At pH 5.0, L-tyr was selective only towards Tl(III), while total thallium was determined directly by stabilized temperature platform furnace-electrothermal atomic absorption spectrometry (STPF-ETAAS). The Tl(III) specie, which was retained by L-tyrosine, was quantitatively eluted from the column with 10% of nitric acid. An on-line breakthrough curve was used to determine the column capacity, which resulted to be 9.00 {mu}mol of Tl(III) g{sup -1} of L-tyr-CNTs with a molar ratio of 0.14 (moles of Tl bound to moles of L-tyr at pH 5). Transient peak areas revealed that Tl stripping from the column occurred instantaneously. Effects of sample flow rate, concentration and flow rate of the eluent, and interfering ions on the recovery of the analyte were systematically investigated. The detection limit for the determination of total thallium (3{sigma}) by STPF-ETAAS was 150 ng L{sup -1}. The detection limit (3{sigma}) for Tl(III) employing the separation system was 3 ng L{sup -1}, with an enrichment factor of 40. The precision of the method expressed as the relative standard deviation (RSD) resulted to be 3.4%. The proposed method was applied to the speciation and determination of inorganic thallium in tap water samples. The found concentrations were in the range of 0.88-0.91 {mu}g L{sup -1} of Tl(III), and 3.69-3.91 {mu}g L{sup -1} of total thallium.

  3. Thallium in mineral resources extracted in Poland

    Directory of Open Access Journals (Sweden)

    Bojakowska I.

    2013-04-01

    Full Text Available Thallium concentrations in primary mineral commodities extracted in Poland and processed in high temperatures were determined by ICP-MS method. Samples of hard and brown coal, copper-silver and zinclead ores, argillaceous and calcareous rocks of different genesis and age were analyzed. The highest thallium concentrations occur in the zinc-lead ores, the average content being of 52.1 mg/kg. The copper ores contain in average 1.4 mg/kg of thallium. Hard coals from the Upper Silesian Coal Basin display higher thallium content than those exploited in the Lublin Coal Basin. Brown coals from Turow deposit distinguish by much higher values, 0.7 mg/kg Tl, than those from huge Bełchatów and smaller Konin-Turek region deposits. Average thallium concentrations in clays used for ceramic materials are lower than 1 mg/kg, except of Mio-Pliocene Slowiany deposit. The average content of thallium in the studied limestone and dolomite raw materials for cement, lime, and metallurgical flux, and refractories is very low in comparison to the average amounts in the world carbonate rocks.

  4. Studies on the adsorption of caesium, thallium, strontium and cobalt radionuclides on activated carbons from aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Rivera-Utrilla, J.; Ferro-Garcia, M.A.; Mata-Arjona, A.; Gonzalez-Gomez, C. (Granada Univ. (Spain). Dept. of Inorganic Chemistry)

    1984-07-01

    Individual adsorption studies of Cs/sup +/, Tl/sup +/, Sr/sup 2 +/ and Co/sup 2 +/ on activated carbons from aqueous solutions are reported. The carbon samples were characterised using different techniques. The surface area and the micro-, meso- and macropore volumes of all samples have been calculated. The chemical nature of the surface of the activated carbons was also studied. Optimal conditions for the adsorption of the metal ions have been identified. The adsorption of these cations by the carbon samples was also determined in the presence of a number of different anions. The data suggest the possible use of activated carbons for the preconcentration and separation of some cations.

  5. Extracorporeal treatment for thallium poisoning

    DEFF Research Database (Denmark)

    Ghannoum, Marc; Nolin, Thomas D; Goldfarb, David S

    2012-01-01

    The EXtracorporeal TReatments In Poisoning (EXTRIP) workgroup was formed to provide recommendations on the use of extracorporeal treatment (ECTR) in poisoning. To test and validate its methods, the workgroup reviewed data for thallium (Tl)....

  6. Usefulness of Thallium Scan for Differential Diagnosis of Breast Mass

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Sang Kyun; Yum, Ha Yong; Lee, Chung Han; Choi, Kyung Hyun [Kosin University College of Medicine, Pusan (Korea, Republic of)

    1994-07-15

    The purpose of this study is to evaluate thallium scanning as a potential test in differentiating malignant from benign lesions of breast. Thirty-one female patients underwent thallium scan of the breast. After intravenous injection of 74-111 MBq(2-3 mCi)of thallium-201, anterior and lateral images were obtained. We compared thallium scans with pathological results. Of 11 patients with breast cancers, 10 cases (90.9%) were detected using thallium scan. Thallium scan obtained in one patient who had breast cancer but received several cycles of chemotherapy did not show thallium uptake. The smallest detectable cancer was 1.5 cm in diameter. In contrast, there is no thallium accumulation in breasts of 17 of 20 patients with benign disease (85%), Three cases of 13 fibrocystic disease show thallium uptake in their breast. In conclusion, thallium scan is an effective test in differentiating benign from malignant lesion.

  7. Thallium contamination of water in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Cheam, V. [National Water Research Institute Branch, Burlington, ON (Canada). Aquatic Ecosystems Protection Research Branch

    2001-07-01

    A highly sensitive instrument, a Laser-Excited Atomic Fluorescence Spectrometer, has been developed to study thallium contamination in some important Canadian ecosystems from the Arctic (containing very low thallium concentration) to coal-related industries across Canada and even to the study of thallium toxicity in an invertebrate, Hyalella azteca. Overall, the data indicate that the coal power plants and mines contain higher thallium concentrations than the other ecosystems studied, and the eastern region has the highest Tl concentrations compared to other regions. The range of thallium concentration in ng/L for the Arctic snow and ice was between not detected and 8.4, for the Great Lakes waters 0.9 to 48, for pore waters 0.1 to 213, for western coal power plants and mines 0.1 to 1326, for central coal power plants 1.2 to 175, for eastern coal power plants and mines 0.2 to 23605, and for miscellaneous sites across Canada not detected to 4390 ng/L. Some of these high concentrations and those high ones reported in industrial wastewaters exceeded the chronic toxicity endpoints for Hyalella azteca mortality, growth and reproduction, and thus can cause serious distress to the environment. All data were integrated into a map of thallium distribution, the first one in Canada. Natural background level of thallium for the Arctic was estimated to be 0.02 to 0.03 pg/g.

  8. IRIS Toxicological Review of Thallium and Compounds ...

    Science.gov (United States)

    Thallium compounds are used in the semiconductor industry, the manufacture of optic lenses and low-melting glass, low-temperature thermometers, alloys, electronic devices, mercury lamps, fireworks, and imitation germs, and clinically as an imaging agent in the diagnosis of certain tumors. EPA's assessment of noncancer health effects and carcinogenic potential of thallium compounds was last prepared and added to the IRIS database between 1988 and 1990. The IRIS program is preparing an assessment that will incorporate current health effects information available for thallium and compounds, and current risk assessment methods. The IRIS assessment for thallium compounds will consist of a Toxicological Review and IRIS Summary. The Toxicological Review is a critical review of the physiochemical and toxicokinetic properties of a chemical, and its toxicity in humans and experimental systems. The assessment will present reference values for the noncancer effects of thallium compounds (RfD and Rfc), and a cancer assessment. The Toxicological Review and IRIS Summary have been subject to Agency review, Interagency review, and external scientific peer review. The final product will reflect the Agency opinion on the overall toxicity of thallium and compounds. EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for thallium and compounds. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effec

  9. Repeat thallium-201 SPECT in cerebral lymphoma.

    Science.gov (United States)

    Borggreve, F; Dierckx, R A; Crols, R; Mathijs, R; Appel, B; Vandevivere, J; Mariën, P; Martin, J J; De Deyn, P P

    1993-01-01

    The authors report on the contribution of Thallium-201 brain SPECT in the diagnosis and follow-up of a non-immunosuppressed patient, presenting with primary cerebral lymphoma. The tumoral process was at first not diagnosed on CT-scan, but Thallium-201 SPECT suggested a tumoral invasion. During corticosteroid treatment the tumor volume on CT-scan decreased, while on Thallium-201 SPECT there was an enhancement of the accumulation and an increasing tumor to non-tumor ratio. These scintigraphical findings more closely reflected the clinical course and the postmortem results.

  10. Thallium poisoning from maliciously contaminated food.

    Science.gov (United States)

    Meggs, W J; Hoffman, R S; Shih, R D; Weisman, R S; Goldfrank, L R

    1994-01-01

    Four young adults presented two days after one of them had received marzipan balls packaged in a box from an expensive candy manufacturer. Two ate one candy ball, while two others shared a third. The next day, variable gastrointestinal symptoms developed. On the third day, two patients developed painful paresthesiae of the hands and feet, an early but nonspecific clinical marker of thallium poisoning. A tentative diagnosis of thallium poisoning was made based on symptoms, and treatment was initiated. The remaining candies were radiographed. Metallic densities in the candies supported the diagnosis, and atomic absorption spectroscopy was used to quantitate thallium content. Each candy contained a potentially fatal dose. Five to seven days later, hypertension and tachycardia developed in the two patients who had ingested an entire candy. All patients developed alopecia but recovered without overt neurologic or other sequelae. While the diagnosis of thallium poisoning is often delayed until alopecia develops, an early diagnosis favors an effective treatment strategy.

  11. Examining of Thallium in Cigarette Smokers.

    Science.gov (United States)

    Ghaderi, Amir; NasehGhafoori, Payam; Rasouli-Azad, Morad; Sehat, Mojtaba; Mehrzad, Fateme; Nekuei, Mina; Aaseth, Jan; Banafshe, Hamid Reza; Mehrpour, Omid

    2017-08-01

    Smoking is one of the sources of thallium which is considered as a toxic heavy metal. The aim of this study was to determine urinary thallium levels and related variables in smokers, compared to a control group. The study was conducted on 56 participants who had smoked continuously during the year before they were referred to Kashan Smoking Cessation Clinic. Fifty-three nonsmokers who were family members or friends of the smokers were selected as the control group. Urinary thallium was measured in both groups (n = 109) using atomic absorption spectrophotometry. The mean value (with SD) for urinary thallium in the smokers (10.16 ± 1.82 μg/L) was significantly higher than in the control group (2.39 ± 0.63 μg/L). There was a significant relationship between smoking duration and urinary thallium levels (P = 0.003). In a subgroup of smokers who was addicted to opium and opium residues (n = 9), the mean level of thallium (37.5 ± 13.09 μg/L) was significantly higher than in the other smokers (4.93 ± 4.45; P = 0.001). Multiple regression analysis showed opioid abuse, insomnia, and chronic obstructive pulmonary disease (COPD), together were strong predictors of urinary thallium levels in smokers. There was no significant difference in thallium level in hookah smokers (P = 0.299) or in those with COPD compared to other smokers (P = 0.375). Urinary thallium levels of smokers with clinical signs of depression, sleep disorders, memory loss, and sweating were higher than those of smokers without these signs. Since thallium, as other toxic metals is accumulated in the body, and cigarette smoking also involves carcinogenic exposures and health hazards for passively exposed people, the need for cigarette control policies is emphasized.

  12. [Characterization of kale (Brassica oberacea var acephala) under thallium stress by in situ attenuated total reflection FTIR].

    Science.gov (United States)

    Yao, Yan; Zhang, Ping; Wang, Zhen-Chun; Chen, Yong-Heng

    2009-01-01

    The experiment was designed based on consumption of carbon dioxide through the photosynthesis of Brassica oberacea var acephala leaf, and the photosynthesis of kale leaf under thallium stress was investigated by in situ attenuated total reflection FTIR (in situ ATR-FTIR). The ATR-FTIR showed that the absorption peaks of leaves had no obvious difference between plants growing in thallium stress soil and plants growing in non-thallium pollution soil, and the strong peaks at 3,380 cm(-1) could be assigned to the absorption of water, carbohydrate, protein or amide; the strong peaks at 2,916 and 2,850 cm(-1) assigned to the absorption of carbohydrate or aliphatic compound; the peaks at 1,640 cm(-1) assigned to the absorption of water. However, as detected by the in situ ATR-FTIR, the double peaks (negative peaks) at 2,360 and 2,340 cm(-1) that are assigned to the absorption of CO2 appeared and became high gradually. It was showed that kale was carrying photosynthesis. At the same time, the carbon dioxide consumption speed of leaf under thallium stress was obviously larger than that of the blank It was expressed that photosynthesis under thallium stress was stronger than the blank All these represented that kale had certain tolerance to the heavy metal thallium. Meanwhile, the carbon dioxide consumption of grown-up leaf was more than that of young leaf whether or not under thallium stress. It was also indicated that the intensity of photosynthesis in grown-up leaf is higher than that in young leaf.

  13. Thallium-201 scintigraphy in unstable angina pectoris

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    Wackers, F.J.T.; Lie, K.I.; Liem, K.L.; Sokole, E.B.; Samson, G.; Van Der Schoot, J.B.; Durrer, D.

    1978-04-01

    Thallium-201 scintigraphy was performed during the pain free period in 98 patients with unstable angina. Scintiscans were positive in 39 patients, questionable in 27 patients and normal in 32 patients. Eighty-one patients responded favorably to treatment (group I). Seventeen patients had complicated courses (group II) and despite maximal treatment with propranolol either developed infarction (six patients) or continued to have angina necessitating coronary surgery (11 patients). In group I during the pain free period 26 of 81 patients had positive thallium-201 scans, whereas 20 patients had an abnormal ECG at that time; during angina 18 patients had transient ECG changes. In group II during the pain free period 13 of 17 patients had positive scans, whereas two patients had abnormal ECG at that time; during angina 12 patients showed transient ECG changes. The sensitivity to recognize group II was 76% for thallium-201 scintigraphy, 11% for ECG during the pain free period; 70% for ECG during angina; 94% for the combination of either positive scans or abnormal ECG. Thus, positive thallium-201 scans occur in patients with unstable angina, positive scans can be obtained during the pain free period, thallium-201 scans are more frequently positive in patients with complicated course.

  14. Thallium-201 uptake in a benign thymoma

    Energy Technology Data Exchange (ETDEWEB)

    Campeau, R.J.; Ey, E.H.; Varma, D.G.

    1986-07-01

    A 68-year-old woman was admitted with atypical angina. A chest radiograph showed an anterior mediastinal mass that was confirmed on CT. The mass was relatively avascular and separate from the heart and great vessels. She underwent stress thallium testing that demonstrated no exercise-induced ischemia; however, an abnormal focus of thallium activity was present in the anterior mediastinum on stress and redistribution images. Cardiac catheterization demonstrated a normal left ventriculogram, coronary arteries and thoracic aorta. Subsequent surgery and pathologic examination revealed the mass to be a benign thymoma arising in the right lobe of the thymus gland.

  15. Endogenous thiols enhance thallium toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Montes, Sergio; Rios, Camilo [Instituto Nacional de Neurologia y Neurocirugia, ' ' Manuel Velasco Suarez' ' , Departamento de Neuroquimica, Mexico, D.F (Mexico); Soriano, Luz; Monroy-Noyola, Antonio [Universidad Autonoma del Estado de Morelos, Laboratorio de Neuroproteccion, Facultad de Farmacia, Cuernavaca, Morelos (Mexico)

    2007-10-15

    Either L-methionine (L-met) or L-cysteine (L-cys), given alone and in combination with Prussian blue (PB) was characterized as treatment against acute thallium (Tl) toxicity in rats. Animals were intoxicated with 32 mg/kg Tl acetate corresponding to rat LD{sub 50}. Antidotal treatments were administered during 4 days, as follows: (1) vehicle, (2) L-met 100 mg/kg i.p. twice a day, (3) L-cys 100 mg/kg i.p. twice a day, (4) PB 50 mg/kg oral, twice a day, (5) L-met + PB and (6) L-cys + PB. Mortality was as follows: control 50%; L-met 80%; L-cys 80%; PB 20%; L-met + PB 90% and L-cys + PB 100%. In a different experiment, using 16 mg/kg of Tl, tissue levels of this metal were analyzed. PB treatment statistically diminished Tl content in body organs and brain regions (P < 0.01). Whereas, separate treatments of L-met and L-cys failed to decrease Tl content in organs and brain regions; while its administration in combination with PB (L-met + PB and L-cys + PB groups) lowered Tl levels in body organs in the same extent as PB group. Results indicate that L-met and L-cys administered alone or in combination with PB should not be considered suitable treatments against acute Tl toxic effects because this strategy failed to prevent mortality and Tl accumulation in brain. (orig.)

  16. Thallium in fractions of soil formed on floodplain terraces.

    Science.gov (United States)

    Jakubowska, Monika; Pasieczna, Anna; Zembrzuski, Wlodzimierz; Swit, Zbigniew; Lukaszewski, Zenon

    2007-01-01

    Two soils formed on the floodplain terrace of a rivulet flowing through the zinc-lead ore exploration area polluted with thallium and one soil from a floodplain terrace of the reference area were investigated in terms of thallium distribution between soil fractions. Such type of soil is formed on river floodplain terraces next to the main river channel and its composition records the history of river pollution. A sequential extraction of soil according to the BCR protocol was performed with an additional initial stage of extraction with water. Apart from labile thallium, thallium entrapped in the residual parent matter was also determined. Thallium was determined by flow-injection differential-pulse anodic stripping voltammetry. In all three cases, the major fraction is thallium entrapped in parent matter. Top soil from the polluted area contains 49.3% thallium entrapped in the residual parent matter, the bottom soil contains 41% while the reference soil contains 80% in this fraction. The major part of labile thallium is located in the reducible fraction (27.7% of total thallium in the top soil, 27% in the bottom soil and 12.4% of the reference soil). Second in terms of significance is the fraction of oxidizable thallium. The top soil contains 12% of total thallium concentration, the bottom soil contains 19% of total concentration, while the reference soil contains 4.1% of total concentration. The acid soluble/exchangeable fraction of thallium has almost the same significance as the oxidizable fraction. The top soil contains 10.4% of the total concentration, while the bottom soil contains 12% of the total concentration. Water soluble thallium concentration is very small. Comparison of the top and the bottom soil show that thallium has not been transported from the river channel onto the floodplain terrace over a long period.

  17. Characteristics of photoconductivity in thallium monosulfide single ...

    Indian Academy of Sciences (India)

    journal of. March 2007 physics pp. 467–479. Characteristics of photoconductivity in thallium monosulfide single crystals. I M ASHRAF, H A ELSHAIKH and A M BADR. Physics Department ... pendencies of carrier lifetime on light intensity, applied voltage and temperature are also ..... 14, 797 (1935) (in Japanese). [10] A T ...

  18. Extraction separation of thallium (III) from thallium (I) with n-octylaniline.

    Science.gov (United States)

    Shilimkar, Tulshidas N; Anuse, Mansing A; Patil, Kesharsingh J

    2002-01-01

    A novel method is developed for the extraction separation of thallium(III) from salicylate medium with n-octylaniline dissolved in toluene as an extractant. The optimum conditions have been determined by making a critical study of weak acid concentration, extractant concentration, period of equilibration and effect of solvent on the equilibria. The thallium (III) from the pregnant organic phase is stripped with acetate buffer solution (pH 4.7) and determined complexometrically with EDTA. The method affords the sequential separation of thallium(III) from thallium(I) and also commonly associated metal ions such as Al(III), Ga(III), In(III), Fe(III), Bi(III), Sb(III) and Pb(II). It is used for analysis of synthetic mixtures of associated metal ions and alloys. The method is highly selective, simple and reproducible. The reaction takes place at room temperature and requires 15-20 min for extraction and determination of thallium(III).

  19. Thallium bromide iodide crystal acoustic anisotropy examination.

    Science.gov (United States)

    Mantsevich, S N

    2017-03-01

    Thallium bromide iodide crystal also known as KRS-5 is the well known material used in far infrared radiation applications for optical windows and lenses fabrication. The main advantage of this material is the transparency in wide band of wavelengths from 0.53 to 50μm. Despite such advantages as transparency and large acousto-optic figure of merit values, KRS-5 is rarely used in acousto-optics. Nevertheless this material seems to be promising for far infrared acousto-optic applications. The acoustic and acousto-optic properties of KRS-5 needed for the full use in optoelectronics are not well understood to date. In this paper the detailed examination of thallium bromide iodide crystal acoustic properties is presented. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Tracing thallium contamination in soils using isotopes

    Science.gov (United States)

    Vaněk, Aleš; Grösslová, Zuzana; Mihaljevič, Martin; Ettler, Vojtěch; Trubač, Jakub; Teper, Leslaw; Cabala, Jerzy; Rohovec, Jan; Penížek, Vít; Zádorová, Tereza; Pavlů, Lenka; Holubík, Ondřej; Drábek, Ondřej; Němeček, Karel; Houška, Jakub; Ash, Christopher

    2017-04-01

    We report the thallium (Tl) isotope record in moderately contaminated soils, which have been historically affected by emissions from coal-fired power plants. Our findings clearly demonstrate that Tl of anthropogenic (high-temperature) origin with light isotope composition was deposited onto the studied soils, where heavier Tl (ɛ205Tl -1) naturally occurs. The results show a positive linear relationship (R2 = 0.71) between 1/Tl and the isotope record, as determined for all the soils and bedrocks, also indicative of binary Tl mixing between two dominant reservoirs. We also identified significant Tl isotope variations within the products from coal combustion and thermo-desorption experiments with local Tl-rich coal pyrite. Bottom ash exhibited the heaviest Tl isotope composition (ɛ205Tl 0), followed by fly ash (ɛ205Tl between -2.5 and -2.8) and volatile Tl fractions (ɛ205Tl between -6.2 and -10.3), suggesting partial Tl isotope fractionations. Despite the evident role of soil processes in the isotope redistribution, we demonstrate that Tl contamination can be traced in soils, and propose that the isotope data represent a possible tool to aid our understanding of post-depositional Tl dynamics in surface environments for the future. This research was supported by the Czech Science Foundation (grant no. 14-01866S and 17-03211S).

  1. Catalytic properties of Thallium-containing mesoporous silicas

    Directory of Open Access Journals (Sweden)

    A. Baradji

    2017-02-01

    Full Text Available The benzylation of benzene by benzyl chloride over a series of Thallium-containing mesoporous silicas with different Tl contents has been investigated. These materials (Tl-HMS-n have been characterized by chemical analysis, N2 adsorption/desorption isotherm and X-ray diffraction (XRD. The mesoporous Thallium-containing materials showed both high activity and high selectivity for the benzylation of benzene. More interesting is the observation that these catalysts are always active and selective for large molecules like naphthenic compounds such as methoxynaphthalene.

  2. A comparison of the clinical relevance of thallium201 and ...

    African Journals Online (AJOL)

    Thallium-201 is at present the radiotracer of choice for the clinical evaluation of myocardial blood flow. Although different technetium-99m-isonitrile agents have been synthesised recently, only 99mTc-melhoxyisobutyl-isonitrile (99mTc_MIBI) has proved to hold promise for clinical implementation. The myocardial distribution ...

  3. Een bepalingsmethode voor thallium in regenwater met behulp van voltammetrie

    NARCIS (Netherlands)

    Struijs; J.; Wolfs; P.M.; Esseveld; F.G.van

    1985-01-01

    In dit rapport wordt een bepalingmethode beschreven voor thallium in het nanogram/liter-gebied, waarbij gebruik wordt gemaakt van differentiele pulse-anodic stripping voltammetry (DPASV) aan de dunne kwikfilm. Met deze techniek blijkt het mogelijk om de concentratie van dit element rechtstreeks

  4. IRIS Toxicological Review of Thallium and Compounds (External Review Draft)

    Science.gov (United States)

    Thallium compounds are used in the semiconductor industry, the manufacture of optic lenses and low-melting glass, low-temperature thermometers, alloys, electronic devices, mercury lamps, fireworks, and imitation germs, and clinically as an imaging agent in the diagnosis of certai...

  5. Band-Structure of Thallium by the LMTO Method

    DEFF Research Database (Denmark)

    Holtham, P. M.; Jan, J. P.; Skriver, Hans Lomholt

    1977-01-01

    The relativistic band structure of thallium has been calculated using the linear muffin-tin orbital (LMTO) method. The positions and extents of the bands were found to follow the Wigner-Seitz rule approximately, and the origin of the dispersion of the bands was established from the canonical s...

  6. A Simple and Rapid Complexometric Determination of Thallium(III ...

    African Journals Online (AJOL)

    A simple, rapid and selective complexometric method is proposed for the determination of thallium(III), using mercaptoethane(EtSH) as demasking agent. The sample solution containing Tl(III) is first complexed with excess EDTA and the surplus EDTA is removed by titration at pH 5–6 with zinc sulphate solution using ...

  7. Selective Thallium (I Ion Sensor Based on Functionalised ZnO Nanorods

    Directory of Open Access Journals (Sweden)

    Z. H. Ibupoto

    2012-01-01

    Full Text Available Well controlled in length and highly aligned ZnO nanorods were grown on the gold-coated glass substrate by hydrothermal growth method. ZnO nanorods were functionalised with selective thallium (I ion ionophore dibenzyldiaza-18-crown-6 (DBzDA18C6. The thallium ion sensor showed wide linear potentiometric response to thallium (I ion concentrations ( M to  M with high sensitivity of 36.87 ± 1.49 mV/decade. Moreover, thallium (I ion demonstrated fast response time of less than 5 s, high selectivity, reproducibility, storage stability, and negligible response to common interferents. The proposed thallium (I ion-sensor electrode was also used as an indicator electrode in the potentiometric titration, and it has shown good stoichiometric response for the determination of thallium (I ion.

  8. A Simple and Rapid Complexometric Determination of Thallium(III ...

    African Journals Online (AJOL)

    NJD

    2005-10-08

    Oct 8, 2005 ... surplus EDTA is removed by titration at pH 5–6 with zinc sulphate solution using xylenol orange as indicator. ... Reproducible and accurate results are obtained in the concentration range 4–80 mg of thallium with a relative error ≤ ±0.6% .... soluble and stable 1:1 complex with Tl(I) so formed.22 This was.

  9. Thallium in the hydrosphere of south west England

    Energy Technology Data Exchange (ETDEWEB)

    Law, Sin [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Turner, Andrew, E-mail: aturner@plymouth.ac.uk [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

    2011-12-15

    Thallium is a highly toxic metal whose environmental concentrations, distributions and behaviour are not well understood. In the present study we measure the concentrations of Tl in filtered and unfiltered samples of rain, tap, river, estuarine and waste waters collected from south west England. Dissolved Tl was lowest (<20 ng L{sup -1}) in tap water, rain water, treated sewage and landfill effluents, estuarine waters, and rivers draining catchments of sandstones and shales. Concentrations up to about 450 ng L{sup -1} were observed in rivers whose catchments are partly mineralized and where metal mining was historically important, and the highest concentration ({approx}1400 ng L{sup -1}) was measured in water abstracted directly from an abandoned mine. Compared with other trace metals measured (e.g. As, Cd, Co, Cr, Cu, Ni, Pb, Zn), Tl has a low affinity for suspended particles and undergoes little removal by conventional (hydroxide precipitation) treatment of mine water. - Highlights: > Thallium concentrations have been measured in natural and waste waters from south west England. > Dissolved concentrations spanned three orders of magnitude and were highest in water from an abandoned mine. > Inputs associated with historical metal mine workings are the most important to the regional hydrosphere. - Concentrations of dissolved thallium in waters of south west England span two orders of magnitude and are greatest in water from an abandoned mine.

  10. Sodium dithionite as a selective demasking agent for the complexometric determination of thallium

    Directory of Open Access Journals (Sweden)

    PRAKASH SHETTY

    2005-11-01

    Full Text Available Sodium dithionite is proposed as a new demasking agent for the rapid and selective complexometric determination of thallium(III. In the presence of diverse metal ions, thallium (III was first complexed with excess EDTA and the surplus EDTAwas then titrated with a standard zinc sulphate solution at pH 5–6 (hexamine buffer using Xylenol Orange as the indicator. The EDTAequivalent to thallium was then released selectively with sodium dithionite and back titrated with a standard zinc sulphate solution as before. Reproducible and accurate results were obtained in the range 4–100 mg of thallium with a relative error of ±27 % and a coefficient of variation (n = 6 of not more than 0.30 %. The effects of various diverse ions were studied. The method was applied to the determination of thallium in its complexes and in alloys.

  11. [Efficiency of hemoperfusion on clearing thallium based on atomic absorption spectrometry].

    Science.gov (United States)

    Tian, Tian; Wang, Yongan; Nie, Zhiyong; Wang, Jiao; Peng, Xiaobo; Yuan, Ye; Li, Wanhua; Qiu, Zewu; Xue, Yanping; Xiong, Yiru

    2015-04-01

    To determine thallium in whole blood by atomic absorption detection method, and to investigate the eliminating effect of hemoperfusion (HP) for thallium in blood. The blood of Beagle dogs which had not exposed to thallium before were obtained for preparation of thallium nitrate ( TlNO3 )-containing solution in three concentrations according to the conversion formula based on animal weight and volume of blood. HP was performed in the simulated in vivo environment. The content of TlNO3 in blood of the next group was determined on the amount of TlNO3 for the last HP of the former dose group. Thallium quantity in different samples was measured with atomic absorption spectrometer blood samples before and after HP. Finally, the thallium concentration in blood was analyzed statistically. Thallium concentrations showed a good linear relationship in the range of 0-200 μg/L (r = 0.998 4). The intra-day precision (RSD) was lower than 4.913%, the intra-day recovery rate was 96.2%-111.9%; the inter-day precision (RSD) was lower than 7.502%, the inter-day recovery rate was 89.6%-105.2%. The concentration of thallium in blood was significantly reduced after HP per time in high, middle, and low dose groups [(453.43 ± 27.80) mg/L to (56.09 ± 14.44) mg/L in high dose group, F = 8.820, P = 0.003; (64.51 ± 13.60) mg/L to (3.19 ± 0.23) mg/L in middle dose group, F = 36.312, P = 0.000; (5.40 ± 0.98) mg/L to (0.38 ± 0.25) mg/L in low dose group, F = 46.240, P = 0.000 ]. The adsorption rate of four times of HP in high, middle and low dose group were (87.63 ± 2.48 )%, (95.06 ± 1.54 )% and (92.76 ± 4.87)%, respectively, without significant difference (F = 4.231, P = 0.070). The method for measuring thallium was established, and it shows a very stable, simple, sensitive for determination of thallium. HP can effectively remove thallium from blood. Thallium concentration can be reduced by 90% after four times of HP. HP is also effective even when thallium concentration is not high.

  12. Redox-controlled release dynamics of thallium in periodically flooded arable soil.

    Science.gov (United States)

    Antić-Mladenović, Svetlana; Frohne, Tina; Kresović, Mirjana; Stärk, Hans-Joachim; Savić, Dubravka; Ličina, Vlado; Rinklebe, Jörg

    2017-07-01

    To our knowledge, this is the first work to mechanistically study the impact of the redox potential (E H ) and principal factors, such as pH, iron (Fe), manganese (Mn), dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), chlorides (Cl - ) and sulfates (SO 4 2- ), on the release dynamics of thallium (Tl) in periodically flooded soil. We simulated flooding using an automated biogeochemical microcosm system that allows for systematical control of pre-defined redox windows. The E H value was increased mechanistically at intervals of approximately 100 mV from reducing (-211 mV) to oxidizing (475 mV) conditions. Soluble Tl levels (0.02-0.28 μg L -1 ) increased significantly with increases in E H (r = 0.80, p soils along with a determination of the Tl species and monitoring of the Tl content in plants to achieve more detailed insight into soluble Tl behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Left ventricular dilatation and pulmonary thallium uptake after single-photon emission computer tomography using thallium-201 during adenosine-induced coronary hyperemia

    Energy Technology Data Exchange (ETDEWEB)

    Iskandrian, A.S.; Heo, J.; Nguyen, T.; Lyons, E.; Paugh, E. (Philadelphia Heart Institute, PA (USA))

    1990-10-01

    This study examined the implications of left ventricular (LV) dilatation and increased pulmonary thallium uptake during adenosine-induced coronary hyperemia. The lung-to-heart thallium ratio in the initial images was significantly higher in patients with coronary artery disease (CAD) than normal subjects; 0.48 +/- 0.16 in 3-vessel disease (n = 16), 0.43 +/- 0.10 in 2-vessel disease (n = 20), 0.43 +/- 0.08 in 1-vessel disease (n = 16) and 0.36 +/- 0.05 in normal subjects (n = 7) (p less than 0.001, 0.09 and 0.06, respectively). There was a significant correlation between the severity and the extent of the perfusion abnormality (determined from the polar maps) and the lung-to-heart thallium ratio (r = 0.51 and 0.52, respectively, p less than 0.0002). There was also a significant correlation between lung thallium washout and lung-to-heart thallium ratio (r = 0.42, p = 0.0009) and peak heart rate (r = -0.49, p less than 0.0001). The LV dilatation was mostly due to an increase in cavity dimension (30% increase) and to a lesser extent (6% increase) due to increase in LV size. (The cavity dimensions were measured from the short-axis slices at the midventricular level in the initial and delayed images). The dilation was seen in patients with CAD but not in the normal subjects. These changes correlated with the extent and severity of the thallium perfusion abnormality. Thus, adenosine-induced coronary hyperemia may cause LV dilation and increased lung thallium uptake on the basis of subendocardial ischemia.

  14. Early detection of restenosis after successful percutaneous transluminal coronary angioplasty by exercise-redistribution Thallium scintigraphy

    NARCIS (Netherlands)

    W. Wijns (William); P.W.J.C. Serruys (Patrick); J.H.C. Reiber (Johan); P.J. de Feyter (Pim); M.J.B.M. van den Brand (Marcel); M.L. Simoons (Maarten); P.G. Hugenholtz (Paul)

    1985-01-01

    textabstractThe value of exercise testing and thallium scintigraphy in predicting recurrence of angina pectoris and restenosis after a primary successful transluminal coronary angioplasty (PTCA) was prospectively evaluated. In 89 patients, a symptom-limited exercise electrocardiogram (ECG) and

  15. Oral zinc sulphate in treatment of patients with thallium poisoning: A clinical therapeutic trial

    Directory of Open Access Journals (Sweden)

    Ahmed A. Al-Mohammadi

    2011-06-01

    Full Text Available Thallium poisoning is usually associated with typical dermatological features simulating that of zinc deficiency. The aim of this study was to evaluate the role of oral zinc sulphate in the treatment of patients with thallium poisoning.Materials and methods: This clinical therapeutic trial study was conducted in Departments of Dermatology of Baghdad and Basrah Teaching Hospitals from February 2008 - February 2010, where a total of 37 patients with thallium poisoning were enrolled.A detailed history was taken from all patients and complete clinical examination was performed. All patients received zinc sulphate in a dose of 5 mg/kg three times a day few days before confirming the diagnosis of thallium poisoning. Thallium in urine had been measured using the colorimetric method and was positive in all patients. After confirming the diagnosis of thallium poisoning, thallium antidotes Prussian blue was given to 32 patients.Results: Age range of 37 patients was 5-33 (24±5.3 years. The dermatological findings were mainly: anagen hair loss affected the scalp and limbs. Also, dusky ecchymotic red dermatitis like rash was observed on the face and dorsum of hands and legs, while neurological manifestations were mainly of peripheral neuropathy, were reported in 21 (55% patients. All patients but two responded promptly to a trial of zinc sulphate within few days.Conclusion: Oral Zinc sulphate appears to be an effective and safe treatment for thallium poisoning particularly for skin and hair features and in reducing its lethal progression and complications. J Clin Exp Invest 2011;2(2:133-7

  16. Fate of Thallium(I) in Reverse Osmosis and Chlorinated Water Matrices

    Science.gov (United States)

    2014-02-01

    THALLIUM(I) IN REVERSE OSMOSIS AND CHLORINATED WATER MATRICES ECBC-TR-1127 Approved for public release; distribution is unlimited...3. DATES COVERED (From - To) Apr 2010 - Dec 2011 4. TITLE AND SUBTITLE Fate of Thallium(I) in Reverse Osmosis and Chlorinated Water Matrices... osmosis (RO) and RO water with added chlorine (RO-Cl) was measured using inductively coupled plasma optical emission spectroscopy (ICP-OES) for a period of

  17. Thallium in the hydrosphere of south west England.

    Science.gov (United States)

    Law, Sin; Turner, Andrew

    2011-12-01

    Thallium is a highly toxic metal whose environmental concentrations, distributions and behaviour are not well understood. In the present study we measure the concentrations of Tl in filtered and unfiltered samples of rain, tap, river, estuarine and waste waters collected from south west England. Dissolved Tl was lowest (<20 ng L(-1)) in tap water, rain water, treated sewage and landfill effluents, estuarine waters, and rivers draining catchments of sandstones and shales. Concentrations up to about 450 ng L(-1) were observed in rivers whose catchments are partly mineralized and where metal mining was historically important, and the highest concentration (~1400 ng L(-1)) was measured in water abstracted directly from an abandoned mine. Compared with other trace metals measured (e.g. As, Cd, Co, Cr, Cu, Ni, Pb, Zn), Tl has a low affinity for suspended particles and undergoes little removal by conventional (hydroxide precipitation) treatment of mine water. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Qualitative evaluation of coronary flow during anesthetic induction using thallium-201 perfusion scans

    Energy Technology Data Exchange (ETDEWEB)

    Kleinman, B.; Henkin, R.E.; Glisson, S.N.; el-Etr, A.A.; Bakhos, M.; Sullivan, H.J.; Montoya, A.; Pifarre, R.

    1986-02-01

    Qualitative distribution of coronary flow using thallium-201 perfusion scans immediately postintubation was studied in 22 patients scheduled for elective coronary artery bypass surgery. Ten patients received a thiopental (4 mg/kg) and halothane induction. Twelve patients received a fentanyl (100 micrograms/kg) induction. Baseline thallium-201 perfusion scans were performed 24 h prior to surgery. These scans were compared with the scans performed postintubation. A thallium-positive scan was accepted as evidence of relative hypoperfusion. Baseline hemodynamic and ECG data were obtained prior to induction of anesthesia. These data were compared with the data obtained postintubation. Ten patients developed postintubation thallium-perfusion scan defects (thallium-positive scan), even though there was no statistical difference between their baseline hemodynamics and hemodynamics at the time of intubation. There was no difference in the incidence of thallium-positive scans between those patients anesthetized by fentanyl and those patients anesthetized with thiopental-halothane. The authors conclude that relative hypoperfusion, and possibly ischemia, occurred in 45% of patients studied, despite stable hemodynamics, and that the incidence of these events was the same with two different anesthetic techniques.

  19. Comparison of thallium deposition with segmental perfusion in pigs with chronic hibernating myocardium.

    Science.gov (United States)

    Baldwa, Sunil; Rana, Muzamil; Canty, John M; Fallavollita, James A

    2008-12-01

    Viable, chronically dysfunctional myocardium with reduced resting flow (or hibernating myocardium) is an important prognostic factor in ischemic heart disease. Although thallium-201 imaging is frequently used to assess myocardial viability in patients with ischemic cardiomyopathy, there are limited data regarding its deposition in hibernating myocardium, and this data suggest that thallium retention may be supernormal compared with control myocardium. Accordingly, pigs (n=7) were chronically instrumented with a 1.5 mm Delrin stenosis on the proximal left anterior descending coronary artery (LAD) to produce hibernating myocardium. Four months later, severe anteroapical hypokinesis was documented with contrast ventriculography (wall motion score, 0.7+/-0.8; normal=3), and microsphere measurements confirmed reduced resting flow (LAD subendocardium, 0.78+/-0.34 vs. 0.96+/-0.24 ml.min(-1).g(-1) in remote; P<0.001). Absolute deposition of thallium-201 and insulin-stimulated [18F]-2 fluoro-2-deoxyglucose (FDG) were assessed over 1 h and compared with resting flow (n=704 samples). Thallium-201 deposition was only weakly correlated with perfusion (r2=0.20; P<0.001) and was more homogeneously distributed (relative dispersion, 0.12+/-0.03 vs. 0.29+/-0.10 for microsphere flow; P<0.01). Thus after 1 h relative thallium-201 (subendocardium LAD/remote, 0.96+/-0.16) overestimated relative perfusion (0.78+/-0.32; P<0.0001) and underestimated the relative reduction in flow. Viability was confirmed by both histology and preserved FDG uptake. We conclude that under resting conditions, thallium-201 redistribution in hibernating myocardium is nearly complete within 1 h, with similar deposition to remote myocardium despite regional differences in flow. These data suggest that in this time frame thallium-201 deposition may not discriminate hibernating myocardium from dysfunction myocardium with normal resting flow. Since hibernating myocardium has been associated with a worse prognosis

  20. Thallium uptake and biological behaviour in childhood brain tumours

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, E.J.; Howman-Giles, R.; Kellie, S.; Uren, R.F. [Royal Alexandra Hospital for Children, Sydney, NSW (Australia)

    1998-03-01

    Full text: The histopathological grade and radiological appearance of the diverse cerebral neoplasms in childhood frequently poorly reflect their biological behaviour. We examined thallium accumulation prior to treatment (and in several cases, at intervals there after) in 13 children to determine its usefulness as a tumour marker. 23 SPECT studies were acquired 20 minutes after the injection of 1-3 mCi of {sup 201}TI. Thallium index (TI), the ratio of counts in tumour/normal brain, was calculated. No uptake was seen in two patients (pts) with a Grade 1 cerebellar astrocytomas (disease free at 4/12 f/u). Three pts with medulloblastomas were studied. One pt showed intense uptake (Tl =12). His tumour (proliferative antigen stain Ki67 = 50%) recurred early after debulking surgery (Tl +ve prior to CT or MRI changes). The second pt was imaged at relapse (Ki67 = 60%) and showed intense uptake, Tl = 17. The third pt showed lower level uptake (Tl = 2), Ki67 = 5%, and is disease-free at 5/12 (as per {sup 201}TI and MRI). One pt with a Grade 1 brainstem glioma showed Tl = 5 and has progressed rapidly despite low grade histology. Four pts with chiasmatic-hypothalamic gliomas have been studied. Although these neoplasms are usually low grade histologically, their growth properties vary greatly. Two pts with Tl<2.5 have been conservatively managed because of slow tumour growth. The other two pts have Tl>3.5 and have required aggressive treatment for rapid disease progression. One pt with a large pilocytic astrocytoma of the optic chiasm showed Tl = 9.5. Active treatment was not undertaken. One pt with a pineal germ cell tumour showed avid {sup 201}TI uptake (Tl not performed) and has had two normal studies, and is clinically well, since BMT. Avid {sup 201}TI uptake also seen in one pt with cerebral neuroblastoma. (Died at 8/12 after Dx.) Thus, {sup 201}TI accumulates in histologically diverse paediatric neoplasms. The Tl appears to reflect biological behaviour in the limited

  1. Evaluation of muscular lesions in connective tissue diseases: thallium 201 muscular scans

    Energy Technology Data Exchange (ETDEWEB)

    Guillet, G.; Guillet, J.; Sanciaume, C.; Maleville, J.; Geniaux, M.; Morin, P.

    1988-04-01

    We performed thallium 201 muscle scans to assess muscular involvement in 40 patients with different connective tissue diseases (7 with dermatomyositis, 7 with systemic lupus erythematosus, 12 with progressive systemic scleroderma, 2 with calcinosis, Raynaud's phenomenon, esophageal involvement, sclerodactyly, and telangiectasia (CREST) syndrome, 3 with monomelic scleroderma, 6 with morphea, and 3 with Raynaud's disease). Only 12 of these patients complained of fatigability and/or myalgia. Electromyography was performed and serum levels of muscle enzymes were measured in all patients. Comparison of thallium 201 exercise recording with the other tests revealed that scan sensitivity is greater than electromyographic and serum muscle enzymes levels. Thallium 201 scans showed abnormal findings in 32 patients and revealed subclinical lesions in 18 patients, while electromyography findings were abnormal in 25 of these 32 patients. Serum enzyme levels were raised in only 8 patients. Thallium 201 scanning proved to be a useful guide for modifying therapy when laboratory data were conflicting. It was useful to evaluate treatment efficacy. Because our data indicate a 100% positive predictive value, we believe that thallium 201 scanning should be advised for severe systemic connective tissue diseases with discordant test results.

  2. Exercise-induced thallium-201 myocardial perfusion defects in angina pectoris without significant coronary artery stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Nakazato, Masayasu; Maruoka, Yuji; Sunagawa, Osahiko; Kinjo, Kunihiko; Tomori, Masayuki; Fukiyama, Koshiro (Ryukyu Univ., Nishihara, Okinawa (Japan). School of Medicine)

    1990-01-01

    We performed exercise thallium-201 myocardial scintigraphy in 32 patients with angina pectoris to study the incidence of perfusion defects, who had no significant organic stenosis on coronary angiography. None of them had myocardial infarction or cardiomyopathy. Thallium-201 myocardial scintigraphy and 12-lead ECG recording were performed during supine bicycle ergometer exercise. Perfusion defects in thallium-201 scintigrams in SPECT images were assessed during visual analysis by two observers. In the coronary angiograms obtained during intravenous infusion of nitroglycerin, the luminal diameter of 75% stenosis or less in the AHA classification was regarded as an insignificant organic stenosis. Myocardial perfusion defects in the thallium-201 scintigrams were detected in eight (25%) of the 32 patients. Six of these eight patients had variant angina documented during spontaneous attacks with ST elevations in standard 12-lead ECGs. Perfusion defects were demonstrated at the inferior or infero-posterior regions in six patients, one of whom had concomitant anteroseptal defect. The defects were not always accompanied by chest pain. All but one patient demonstrating inferior or inferoposterior defects showed ST depression in leads II, III and aV{sub F} on their ECGs, corresponding to inferior wall ischemia. The exception was a case with right bundle branch block. Thus, 25% of the patients with angina pectoris, who had no evidence of significant organic stenosis on their coronary angiograms, exhibited exercise-induced perfusion defects in their thallium-201 scintigrams. Coronary spasms might have caused myocardial ischemia in these patients. (author).

  3. Advanced crystal growth techniques for thallium bromide semiconductor radiation detectors

    Science.gov (United States)

    Datta, Amlan; Becla, Piotr; Guguschev, Christo; Motakef, Shariar

    2018-02-01

    Thallium Bromide (TlBr) is a promising room-temperature radiation detector candidate with excellent charge transport properties. Currently, Travelling Molten Zone (TMZ) technique is widely used for growth of semiconductor-grade TlBr crystals. However, there are several challenges associated with this type of crystal growth process including lower yield, high thermal stress, and low crystal uniformity. To overcome these shortcomings of the current technique, several different crystal growth techniques have been implemented in this study. These include: Vertical Bridgman (VB), Physical Vapor Transport (PVT), Edge-defined Film-fed Growth (EFG), and Czochralski Growth (Cz). Techniques based on melt pulling (EFG and Cz) were demonstrated for the first time for semiconductor grade TlBr material. The viability of each process along with the associated challenges for TlBr growth has been discussed. The purity of the TlBr crystals along with its crystalline and electronic properties were analyzed and correlated with the growth techniques. Uncorrected 662 keV energy resolutions around 2% were obtained from 5 mm x 5 mm x 10 mm TlBr devices with virtual Frisch-grid configuration.

  4. Thallium distribution in sediments from the Pearl river basin, China

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Juan [Guangzhou University, Key Laboratory of Waters Safety and Protection in the Pearl River Delta, Ministry of Education, Guangzhou (China); Forschungszentrum Dresden-Rossendorf (FZD), Institute of Radiochemistry, Research Site Leipzig, Leipzig (Germany); Wang, Jin; Chen, Yongheng [Guangzhou University, Key Laboratory of Waters Safety and Protection in the Pearl River Delta, Ministry of Education, Guangzhou (China); Qi, Jianying [Department of Environmental Science and Engineering, Guangzhou University, Guangzhou (China); Lippold, Holger [Forschungszentrum Dresden-Rossendorf (FZD), Institute of Radiochemistry, Research Site Leipzig, Leipzig (Germany); Wang, Chunlin [Guangdong Provincial Academy of Environmental Science, Guangzhou (China)

    2010-10-15

    Thallium (Tl) is a rare element of high toxicity. Sediments sampled in three representative locations near industries utilizing Tl-containing raw materials from the Pearl River Basin, China were analyzed for their total Tl contents and the Tl contents in four sequentially extracted fractions (i.e., weak acid exchangeable, reducible, oxidizable, and residual fraction). The results reveal that the total Tl contents (1.25-19.1 {mu}g/g) in the studied sediments were slightly high to quite high compared with those in the Chinese background sediments. This indicates the apparent Tl contamination of the investigated sediments. However, with respect to the chemical fractions, Tl is mainly associated with the residual fraction (>60%) of the sediments, especially of those from the mining area of Tl-bearing pyrite minerals, indicating the relatively low mobility, and low bioavailability of Tl in these sediments. This obviously contrasts with the previous findings that Tl is mainly entrapped in the first three labile fractions of the contaminated samples. Possible reasons were given for the dominating association of Tl with the residual fraction (>95%) of the mining area sediments. The significant role of certain K-containing silicates or minerals of these sediments on retaining Tl in the residual fraction, discovered by this study, provides a special field of research opportunity for the Tl-containing wastewater treatment. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. [Graphite furnace atomic absorption spectrometry for determination of thallium in blood].

    Science.gov (United States)

    Zhang, Q L; Gao, G

    2016-04-20

    Colloidal palladium was used as chemical modifier in the determination of blood thallium by graphite furnace atomic absorption spectrometry. Blood samples were precipitated with 5% (V/V)nitric acid, and then determined by GFAAS with colloidal palladium used as a chemical modifier. 0.2% (W/V)sodium chloride was added in the standard series to improve the matrix matching between standard solution and sample. The detection limit was 0.2 μg/L. The correlation coefficient was 0.9991. The recoveries were between 93.9% to 101.5%.The relative standard deviations were between 1.8% to 2.7%.The certified reference material of whole blood thallium was determined and the result was within the reference range Conclusion: The method is accurate, simple and sensitive, and it can meet the needs of detection thallium in blood entirely.

  6. Myocardial perfusion defect on thallium-201 imaging in patients with chronic obstructive pulmonary disease

    Energy Technology Data Exchange (ETDEWEB)

    Mehrotra, P.P.; Weaver, Y.J.; Higginbotham, E.A.

    1983-08-01

    Six patients with angina pectoris had reversible perfusion defects on stress and redistribution thallium imaging. Three patients had a positive electrocardiographic response to exercise. No significant coronary artery lesions were seen on coronary arteriography in any of the six patients. All had mild to moderate hypoxemia at rest and physiologic evidence of chronic obstructive pulmonary disease as defined by the decrease in the ratio of forced expiratory volume at 1 second to forced vital capacity (FEV1/FVC X 100) or decrease in the forced midexpiratory flow rate (FEF25-75), or both. None had clinical findings suggestive of any of the reported causes of positive thallium scans in patients with normal coronary arteriograms. Cellular dysfunction produced by hypoxemia affecting the uptake of thallium seems to be the most likely mechanism of this abnormality.

  7. Early and delayed thallium-201 scintigraphy in thyroid nodules: the relationship between early thallium-201 uptake and perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Derebek, E. [Dept. of Nuclear Medicine, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Biberoglu, S. [Dept. of Internal Medicine, Div. of Endocrinology, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Kut, O. [Dept. of Nuclear Medicine, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Yesil, S. [Dept. of Internal Medicine, Div. of Endocrinology, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Saydam, S. [Dept. of Surgery, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Yilmaz, M. [Dept. of Nuclear Medicine, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Yenici, O. [Dept. of Nuclear Medicine, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Igci, E. [Dept. of Radiology, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Gokce, O. [Dept. of Surgery, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Canda, S. [Dept. of Pathology, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Bueyuekgebiz, A. [Dept. of Pediatrics, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Dogan, A.S. [Dept. of Nuclear Medicine, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey); Durak, H. [Dept. of Nuclear Medicine, Dokuz Eylul Univ., School of Medicine, Izmir (Turkey)

    1996-05-01

    Seventy-six patients with tyroid nodules were studied. Initially, 75 MBq of thallium-201 was injected. The thyroid gland was imaged 15 min (early) and 3 h (delayed) after the injection. Thereafter, 185 MBq technetium-99m pertechnetate was injected. Immediately after the injection, a 1-min perfusion image was acquired, followed by an image at 20 min. Increased early and delayed {sup 201}Tl uptake compared with the contralateral thyroid tissue was adopted as the criterion for malignancy. Sensitivity, specificity and negative predictive values were found to be 85%, 64% and 78%, respectively, in operated patients, but these values were 86%, 87% and 95%, respectively, in the whole group, including patients followed with fine-needle aspiration biopsy. With the purpose of investigating the relationship between perfusion and early {sup 201}Tl uptake, bot perfusion and early images were graded comparing nodular activity with contralateral thyroid activity. There was a poor correlation between perfusion and {sup 201}Tl uptake. The correlation was even worse in hyperactive nodules. It is concluded that early and delayed {sup 201}Tl imaging should not be used in the differential diagnosis of cold nodules and that early {sup 201}Tl uptake seems to be more closely related to factors other than perfusion. (orig.)

  8. Overlapping toxic effect of long term thallium exposure on white mustard (Sinapis alba L.) photosynthetic activity.

    Science.gov (United States)

    Mazur, Radosław; Sadowska, Monika; Kowalewska, Łucja; Abratowska, Agnieszka; Kalaji, Hazem M; Mostowska, Agnieszka; Garstka, Maciej; Krasnodębska-Ostręga, Beata

    2016-09-02

    Heavy metal exposure affect plant productivity by interfering, directly and indirectly, with photosynthetic reactions. The toxic effect of heavy metals on photosynthetic reactions has been reported in wide-ranging studies, however there is paucity of data in the literature concerning thallium (Tl) toxicity. Thallium is ubiquitous natural trace element and is considered the most toxic of heavy metals; however, some plant species, such as white mustard (Sinapis alba L.) are able to accumulate thallium at very high concentrations. In this study we identified the main sites of the photosynthetic process inhibited either directly or indirectly by thallium, and elucidated possible detoxification mechanisms in S. alba. We studied the toxicity of thallium in white mustard (S. alba) growing plants and demonstrated that tolerance of plants to thallium (the root test) decreased with the increasing Tl(I) ions concentration in culture media. The root growth of plants exposed to Tl at 100 μg L(-1) for 4 weeks was similar to that in control plants, while in plants grown with Tl at 1,000 μg L(-1) root growth was strongly inhibited. In leaves, toxic effect became gradually visible in response to increasing concentration of Tl (100 - 1,000 μg L(-1)) with discoloration spreading around main vascular bundles of the leaf blade; whereas leaf margins remained green. Subsequent structural analyses using chlorophyll fluorescence, microscopy, and pigment and protein analysis have revealed different effects of varying Tl concentrations on leaf tissue. At lower concentration partial rearrangement of the photosynthetic complexes was observed without significant changes in the chloroplast structure and the pigment and protein levels. At higher concentrations, the decrease of PSI and PSII quantum yields and massive oxidation of pigments was observed in discolored leaf areas, which contained high amount of Tl. Substantial decline of the photosystem core proteins and disorder of the

  9. Stable room-temperature thallium bromide semiconductor radiation detectors

    Science.gov (United States)

    Datta, A.; Fiala, J.; Becla, P.; Motakef, Shariar

    2017-10-01

    Thallium bromide (TlBr) is a highly efficient ionic semiconductor with excellent radiation detection properties. However, at room temperature, TlBr devices polarize under an applied electric field. This phenomenon not only degrades the charge collection efficiency of the detectors but also promotes chemical reaction of the metal electrodes with bromine, resulting in an unstable electric field and premature failure of the device. This drawback has been crippling the TlBr semiconductor radiation detector technology over the past few decades. In this exhaustive study, this polarization phenomenon has been counteracted using innovative bias polarity switching schemes. Here the highly mobile Br- species, with an estimated electro-diffusion velocity of 10-8 cm/s, face opposing electro-migration forces during every polarity switch. This minimizes the device polarization and availability of Br- ions near the metal electrode. Our results indicate that it is possible to achieve longer device lifetimes spanning more than 17 000 h (five years of 8 × 7 operation) for planar and pixelated radiation detectors using this technique. On the other hand, at constant bias, 2500 h is the longest reported lifetime with most devices less than 1000 h. After testing several biasing switching schemes, it is concluded that the critical bias switching frequency at an applied bias of 1000 V/cm is about 17 μHz. Using this groundbreaking result, it will now be possible to deploy this highly efficient room temperature semiconductor material for field applications in homeland security, medical imaging, and physics research.

  10. Thallium pollution in China: A geo-environmental perspective.

    Science.gov (United States)

    Xiao, Tangfu; Yang, Fei; Li, Shehong; Zheng, Baoshan; Ning, Zengping

    2012-04-01

    It is well known that thallium (Tl) is a non-essential and toxic metal to human health, but less is known about the geo-environmentally-induced Tl pollution and its associated health impacts. High concentrations of Tl that are primarily associated with the epithermal metallogenesis of sulfide minerals have the potential of producing Tl pollution in the environment, which has been recognized as an emerging pollutant in China. This paper aims to review the research progress in China on Tl pollution in terms of the source, mobility, transportation pathway, and health exposure of Tl and to address the environmental concerns on Tl pollution in a geo-environmental perspective. Tl associated with the epithermal metallogenesis of sulfide minerals has been documented to disperse readily and accumulate through the geo-environmental processes of soil enrichment, water transportation and food crop growth beyond a mineralized zone. The enrichments of Tl in local soil, water, and crops may result in Tl pollution and consequent adverse health effects, e.g. chronic Tl poisoning. Investigation of the baseline Tl in the geo-environment, proper land use and health-related environmental planning and regulation are critical to prevent the Tl pollution. Examination of the human urinary Tl concentration is a quick approach to identify exposure of Tl pollution to humans. The experiences of Tl pollution in China can provide important lessons for many other regions in the world with similar geo-environmental contexts because of the high mobility and toxicity of Tl. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Stable room-temperature thallium bromide semiconductor radiation detectors

    Directory of Open Access Journals (Sweden)

    A. Datta

    2017-10-01

    Full Text Available Thallium bromide (TlBr is a highly efficient ionic semiconductor with excellent radiation detection properties. However, at room temperature, TlBr devices polarize under an applied electric field. This phenomenon not only degrades the charge collection efficiency of the detectors but also promotes chemical reaction of the metal electrodes with bromine, resulting in an unstable electric field and premature failure of the device. This drawback has been crippling the TlBr semiconductor radiation detector technology over the past few decades. In this exhaustive study, this polarization phenomenon has been counteracted using innovative bias polarity switching schemes. Here the highly mobile Br− species, with an estimated electro-diffusion velocity of 10−8 cm/s, face opposing electro-migration forces during every polarity switch. This minimizes the device polarization and availability of Br− ions near the metal electrode. Our results indicate that it is possible to achieve longer device lifetimes spanning more than 17 000 h (five years of 8 × 7 operation for planar and pixelated radiation detectors using this technique. On the other hand, at constant bias, 2500 h is the longest reported lifetime with most devices less than 1000 h. After testing several biasing switching schemes, it is concluded that the critical bias switching frequency at an applied bias of 1000 V/cm is about 17 μHz. Using this groundbreaking result, it will now be possible to deploy this highly efficient room temperature semiconductor material for field applications in homeland security, medical imaging, and physics research.

  12. Medical geology of arsenic, selenium and thallium in China.

    Science.gov (United States)

    Li, Shehong; Xiao, Tangfu; Zheng, Baoshan

    2012-04-01

    Arsenic (As), selenium (Se) and thallium (Tl) are three trace metals (metalloids) of high concern in China because deficiency or excess expose can cause a range of endemic diseases, such as endemic arsenism, selenosis, Keshan disease (KD), Kashin-Beck disease (KBD) and thallotoxicosis. These specific endemic diseases were attributable for overabundance or deficiency (mainly referring to selenium) of these three elements in the local environment as a result of natural geochemical processes and/or anthropologic activities. The geochemistry and human health impacts of these three trace elements have been intensively studied since the 1970s in China, in terms of geochemical sources, distribution, transportation, health impact pathways, and prevention/remediation measures. Endemic arsenism in China are induced from the exposures of high As in either drinking water or domestic combustion of As-rich coals. Both endemic selenium deficiency and selenosis occurred in China. The KD and KBD were related to the deficiency of Se in the low-Se geological belt with Se contents in soil less than 0.125mg/kg stretching from northeast to southwest of China. Endemic selenosis occurred in areas with high Se concentrations in soils derived from the Se-enriched black carbonaceous siliceous rocks, carbonaceous shale and slate. Endemic Tl poisoning occurred in southwestern China due to Tl contamination in local drinking water and vegetables surrounding the Tl-rich sulfide mineralized areas. Some measures have been taken to control and remedy the endemic diseases with significant effects in reducing health risk and damage of As, Se and Tl. However, the states of the endemic diseases of As, Se and Tl in China are still serious in some areas, and substantial research efforts regarding the health impacts of these elements are further required. This paper reviews the progress of medical geology of As, Se and Tl in China, and provides with some outlooks for future research directions. Copyright

  13. New CZT cardiac cameras and myocardial perfusion imaging with thallium 201; Nouvelles cameras cardiaques a semi-conducteur cadmium -zinc- telluride (CZT) et scintigraphies myocardiques au thallium 201

    Energy Technology Data Exchange (ETDEWEB)

    Songy, B. [Service de medecine et imagerie nucleaire, centre cardiologique du Nord (CCN), 93 - Saint-Denis (France)

    2010-08-15

    Myocardial perfusion imaging is widely used for management of coronary artery disease. However, it suffers from technical limitations. New cardiac cameras using CZT detectors are now available and increase spatial (x2) and energy (x2) resolutions and photons sensitivity (x5). We describe here the General Electric Discovery NM 530c new camera and summarize the validation studies with technetium agents and with thallium 201, protocols to reduce doses, ultrafast protocols and perspectives offered with this new technology. (author)

  14. Genotoxic and mutagenic effects of the diagnostic use of thallium-201 in nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Kelsey, K.T. (Harvard School of Public Health, Boston, MA (United States)); Donohoe, K.J. (Beth Israel Hospital, Boston, MA (United States). Div. of Nuclear Medicine); Baxter, Barbara; Memisoglu, Asli; Little, J.B.; Caggana, Michele; Liber, H.L. (Harvard School of Public Health, Boston, MA (United States))

    1991-07-01

    In order to investigate possible mutagenetic effects of in vivo exposure to low levels of ionizing radiation used in nuclear medicine, the authors examined hypoxanthine guanine phosphoribosyl transferase (hprt) mutant fraction (MF) and chromosome aberration (CA) frequency in 24 nuclear medicine patients before and after injection of thallium-201. The mean MF of the thallium-201-exposed cohort was 5.2{+-}4.4 x 10{sup -6} before injection exposure. No significant difference in MF was observed 24 h later. In 11 patients who were studied on a 3rd occasion, 30 days after thallium-201 exposure, there was again no significant difference in post-exposure as compared with the pre-exposure MF. The frequency of CA in peripheral blood lymphocytes was not significantly different, comparing pre- and 24h to 1 month post-radionuclide exposure . Thus, thallium-201 exposure was not associated with significant elevations in MF or CA frequency in lymphocytes of exposed individuals. (author). 40 refs.; 3 tabs.

  15. Systematics of c-axis Phonons in the Thallium- and Bismuth-Based Cuprate Superconductors

    NARCIS (Netherlands)

    Tsvetkov, A. A; Dulic, D.; Marel, D. van der; Damascelli, A.; Kaljushnaia, G. A.; Gorina, J. I.; Senturina, N. N.; Kolesnikov, N. N.; Ren, Z. F.; Wang, J. H.; Menovsky, A. A.; Palstra, T. T. M.

    2006-01-01

    Published in: Phys. Rev. B 60 (1999) 13196 Citing articles (CrossRef) citations recorded in [Science Citation Index] Abstract: We present grazing incidence reflectivity measurements in the far infrared region at temperatures above and below Tc for a series of thallium (Tl2Ba2CuO6, Tl2Ba2CaCu2O8) and

  16. Dipyridamole-thallium-201 tomography documenting improved myocardial perfusion with therapy in Kawasaki disease

    Energy Technology Data Exchange (ETDEWEB)

    Nienaber, C.A.; Spielmann, R.P.; Hausdorf, G.

    1988-12-01

    Thallium-201 tomographic perfusion studies after pharmacologic vasodilation were performed in seven children (aged 2 years 8 months to 8 years 7 months), 3 to 20 months after the acute stage of the disease. In all patients coronary aneurysms were seen on cross-sectional echocardiograms. The scintigrams of six children showed no significant regional reduction of myocardial thallium-201 uptake. These children had remained asymptomatic in the follow-up period after the acute inflammatory stage of Kawasaki disease. Persistent and transient thallium defects were present in one child with acute posterolateral myocardial infarction; obstruction of two coronary vessels supplying the defect zones was confirmed by contrast angiography. After 8 months of treatment a follow-up nuclear scan showed marked reduction in the size of the defect and almost complete abolishment of the ischemic reaction. Thus tomographic thallium-201 perfusion scintigraphy in conjunction with vasodilation stress is useful to assess myocardial perfusion in children with Kawasaki disease and demonstrates marked improvement in regional perfusion after adequate medical therapy.

  17. Complexometric determination of thallium(III using ethanethiol as a selective masking agent

    Directory of Open Access Journals (Sweden)

    Karthikeyan J.

    2006-01-01

    Full Text Available A simple and selective complexometric method for the determination of thallium in presence of other metal ions is proposed based on the selective masking ability of ethanethiol towards thallium(III. Thallium present in a given sample solution is first complexed with a known excess of EDTA and the surplus EDTA is titrated with standard zinc sulphate solution at pH 5-6(hexamine using xylenol orange as the indicator. A 0.3% aqueous solution of ethanethiol is then added to displace EDTA from the Tl(III-EDTA complex. The released EDTA is titrated with standard zinc sulphate solution as before. Reproducible and accurate results are obtained for 3.70 mg to 74.07 mg of Tl (III with relative error less than ? 0.44% and coefficient of variation not more than 0.27%. The interference of various ions was studied and the method was used for the analysis of thallium in its synthetic alloy mixtures and also in complexes.

  18. Thallium-201: Autoradiography in pigmented mice and melanin-binding in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Tjaelve, H.; Nilsson, M.; Larsson, B. (Uppsala Univ. (Sweden))

    1982-01-01

    Autoradiography with /sup 201/Tl/sup +/ in C57Bl mice showed a strong labelling of the eye melanin and of pigmented hair follicles. An analysis of the affinity of thallium for pigment from cow eyes indicated a binding to three groups of sites and showed a marked sensitivity to the addition of H/sup +/-ions. The results are consistent with the conception that a binding of thallium occurs to the free carboxyl groups of the melanin and that the structure of the polymer has a marked influence on the affinity. Similar results have previously been obtained with other cations. There was no indication that the strong in vivo affinity of thallium to melanin is due to a more firm binding than for other cations which do not localize on melanin in vivo. Instead, the ability of cations to pass the melanocyte membranes and reach the melanin granules is probably decisive for whether a melanin-binding will take place in vivo. Toxic effects on the eye and epilation are symptoms of thallium intoxication which may be related to its melanin-binding. The fate of /sup 201/Tl/sup +/ in some other tissues is also described and discussed.

  19. Laser-assisted decay and optical spectroscopy studies of neutron-deficient thallium isotopes

    CERN Document Server

    Van Beveren, Céline; Huyse, Mark

    The neutron-deficient thallium isotopes with one proton less than the Z = 82 shell closure, are situated in an interesting region of the nuclear chart, notorious for intruder states and shape coexistence. Shape coexistence is the remarkable phenomenon in which two or more distinct types of deformation occur at low energy in the same atomic nucleus. Shape coexistence has been studied intensively, experimentally as well as theoretically in different nuclei in the light-lead region and the isomerism in the thallium isotopes was among the first indications of this phenomenon. Different shapes, whose structure has been linked to specific proton orbitals above and below the Z = 82 shell closure, are present at low energy in the neutron-deficient odd-mass thallium nuclei. In the odd-odd nuclei, the coupling of an unpaired proton and unpaired neutron gives rise to multiplets of low-lying states from which some can be isomeric. Since thallium has one proton missing in the major proton shell, and when approaching neutr...

  20. Clinical features and applications of thallium-201. With reference to scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Tadashige

    1988-12-01

    Thallium-201 is not only used widely in myocardial imaging but also has a great potential in other various nuclear medicine imaging studies. This paper presents clinical features and applications of thallium-201, focusing on clinical trials with thallium-201 at the Shinshu University School of Medicine. Thallium-201 myocardial scintigraphy offers information on (1) ventricular position and morphology, (2) hypertrophy or dilatation of the left ventricle, (3) hypertrophy or dilatation of the right ventricle, (4) site and extent of myocardial ischemia and infarct, (5) myocardial blood flow, (6) pulmonary congestion or interstitial pulmonary edema, and (7) pericardial effusion. It can be used in the following evaluation or diagnosis: (1) acute or old myocardial infarction, (2) angina pectoris, (3) treatment strategy or prognosis of ischemic heart disease, (4) treatment strategy or observation of bypass graft or drug therapy, (5) hypertrophic or dilated idiopathic cardiomyopathy, (6) myocardial lesions induced by sarcoidosis, collagen disease, and neuro-muscular disease, (7) ventricular hypertrophy and pulmonary edema, and (9) pericarditis, pericardial effusion, and systolic pericarditis associated with underlying disease. The significance of tumor, liver, bone marrow scintigraphies is also referred to. (Namekawa, K) 69 refs.

  1. Optimised thallium precipitation in a waste water treatment system of the flue gas desulphurisation; Optimierte Thalliumabscheidung einer RAA

    Energy Technology Data Exchange (ETDEWEB)

    Ritzerfeld, Guenter [RWE Power AG, Bergheim (Germany); Birngruber, Ingolf [RWE Power AG, Hamm (Germany); Muelder, Thomas [RWE Power AG, Ibbenbueren (Germany)

    2011-07-01

    When co-combusting substitute fuels in power plants, the element Thallium should be checked in the drain of the waste water treatment system of flue gas desulphurisation. In 2005 Thallium-concentrations exceeding the limit value were determined for the first time as a consequence of the modified analysis of the supervisory authority. The previous lower Thallium concentrations with graphite tube-atomic absorption spectrometry were caused by the high chloride concentration in RAA waste water. The RAA operating mode was checked and changed. Equipment-related weak spots were detected and corrected. (orig.)

  2. Thallium Isotopes Tracking Mn-Oxide Burial - A Proxy for Deoxygenation During Oceanic Anoxic Event 2

    Science.gov (United States)

    Ostrander, C.; Owens, J. D.; Nielsen, S.

    2015-12-01

    Thallium (Tl) is proving to be a useful paleoredox proxy given that the Tl isotope composition of seawater is highly dependent on the magnitude of manganese (Mn) oxide burial in the ocean. In turn, Mn oxides require oxygen at the sediment-water interface to precipitate, linking the Tl isotope cycle to ocean oxygenation. Currently, the marine residence time of Tl is ~20kyrs and the Tl isotope composition of seawater is invariant, which suggests Tl isotopes could be a global tracer of marine Mn-oxide burial. Importantly, recent research suggests sediments deposited under a euxinic water column faithfully record the Tl isotope value of the overlying oxic water column (e.g. Black Sea and Cariaco Basin). Therefore, analysis of organic-rich black shales may prove useful in evaluating the seawater Tl isotope composition of past oceans and, hence, large-scale burial of Mn-oxides and the extent of bottom water ocean oxygenation. A logical test for this proxy is during the well-studied Cenomanian-Turonian boundary event termed Oceanic Anoxic Event 2 (OAE-2) at ~94 Ma. It is known that the global extent of anoxia and euxinia increased during this event, however, to what extent global bottom water deoxygenation occured is unconstrained. If deep water deoxygenation occurred, it would be hypothesized that Mn-oxide precipitation would decrease, resulting in a positive Tl isotope excursion during OAE-2. We have analyzed the Tl isotope composition of organic-rich black shales from Site 1258 of the Ocean Drilling Program (ODP) spanning the period before, during, and after OAE-2. Based on Fe redox proxies, the entire section is euxinic and thus no Mn-oxides are present (i.e. no local redox changes). Before the event, Tl isotope compositions are similar or slightly heavier than modern seawater values. Just prior to the onset of OAE-2, a positive shift occurs and is maintained until recovery, slightly before the termination of the event. The shift to heavier values and subsequent

  3. Comparison of Polythionates as Precursors for the Formation of Thallium Sulfide Layers

    Directory of Open Access Journals (Sweden)

    Vitalijus JANICKIS

    2011-11-01

    Full Text Available The processes of obtaining layers of thallium, sulfides, TlxSy, by the sorption-diffusion method on polyamide 6 using solutions of lower polythionates - sodium trithionate and tetrathionate, Na2S3O6, Na2S4O6, potassium pentathionate, K2S5O6, and of dodecathionic acid, H2S12O6, as precursors of sulfur are compared. The concentration of sorbed sulfur increases with increasing the duration of treatment, the concentration and temperature of precursor solution. It rather significantly also depends on the nature - sulfurity of polythionate, i. e. on the number of sulfur atoms in the polythionate anion: effectiveness of sulfurization using solutions of dodecathionic acid is significantly higher than that of lower polythionates. Thallium sulfide layers are formed on the surface of polyamide after the treatment of sulfurized polymer with Tl(I salt solution. The concentration of thallium in the layer increases with the increase of initial sulfurization duration and in case of H2S12O6 solution used - on the temperature of this process. The results of X-ray diffraction analysis confirmed the formation of thallium sulfide layers in the surface of polyamide 6. The phase composition of layer changes depending on the conditions of initial treatment in a H2S12O6 solution. Five thallium sulfide phases, two forms of TlS, Tl2S2, Tl4S3 and Tl2S5 were identified in the composition of the layers treated for different time with a solution of dodecathionic acid at the temperature of 20 °C and 30 °C and then with Tl(I salt solution by X-ray diffraction but the maxima of TlS and Tl2S5 phases predominate in the diffractograms.http://dx.doi.org/10.5755/j01.ms.17.4.774

  4. Thermodynamic Study of Tl6SBr4 Compound and Some Regularities in Thermodynamic Properties of Thallium Chalcohalides

    Directory of Open Access Journals (Sweden)

    Dunya Mahammad Babanly

    2017-01-01

    Full Text Available The solid-phase diagram of the Tl-TlBr-S system was clarified and the fundamental thermodynamic properties of Tl6SBr4 compound were studied on the basis of electromotive force (EMF measurements of concentration cells relative to a thallium electrode. The EMF results were used to calculate the relative partial thermodynamic functions of thallium in alloys and the standard integral thermodynamic functions (-ΔfG0, -ΔfH0, and S0298 of Tl6SBr4 compound. All data regarding thermodynamic properties of thallium chalcogen-halides are generalized and comparatively analyzed. Consequently, certain regularities between thermodynamic functions of thallium chalcogen-halides and their binary constituents as well as degree of ionization (DI of chemical bonding were revealed.

  5. A calixarene-based ion-selective electrode for thallium(I) detection

    Energy Technology Data Exchange (ETDEWEB)

    Chester, Ryan [Nanochemistry Research Institute, Department of Chemistry, Curtin University, GPO Box U1987, Perth, Western Australia 6845 (Australia); Sohail, Manzar [Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Locked Bag 4, Maroochydore DC, Queensland 4556 (Australia); Ogden, Mark I.; Mocerino, Mauro [Nanochemistry Research Institute, Department of Chemistry, Curtin University, GPO Box U1987, Perth, Western Australia 6845 (Australia); Pretsch, Ernö [ETH Zürich, Institute of Biogeochemistry and Pollutant Dynamics (IBP), Universitätstrasse 16, CH-8092, Zürich (Switzerland); De Marco, Roland, E-mail: rdemarc1@usc.edu.au [Nanochemistry Research Institute, Department of Chemistry, Curtin University, GPO Box U1987, Perth, Western Australia 6845 (Australia); Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Locked Bag 4, Maroochydore DC, Queensland 4556 (Australia)

    2014-12-03

    Highlights: • Tuning of metal binding cavities in thallium(I) calixarene ionophores. • Novel calixarene-based ionophores with improved selectivity for thallium(I). • Sandwich membrane characterization of thallium(I) binding in novel calixarenes. • Improved selectivity and sensitivity with novel thallium(I) calixarene ionophores. • Solid contact ion-selective electrodes for novel thallium(I) calixarene ionophores. - Abstract: Three new calixarene Tl{sup +} ionophores have been utilized in Tl{sup +} ion-selective electrodes (ISEs) yielding Nernstian response in the concentration range of 10{sup −2}–10{sup −6} M TlNO{sub 3} with a non-optimized filling solution in a conventional liquid contact ISE configuration. The complex formation constants (log β{sub IL}) for two of the calixarene derivatives with thallium(I) (i.e. 6.44 and 5.85) were measured using the sandwich membrane technique, with the other ionophore immeasurable due to eventual precipitation of the ionophore during these long-term experiments. Furthermore, the unbiased selectivity coefficients for these ionophores displayed excellent selectivity against Zn{sup 2+}, Ca{sup 2+}, Ba{sup 2+}, Cu{sup 2+}, Cd{sup 2+} and Al{sup 3+} with moderate selectivity against Pb{sup 2+}, Li{sup +}, Na{sup +}, H{sup +}, K{sup +}, NH{sub 4}{sup +} and Cs{sup +}, noting that silver was the only significant interferent with these calixarene-based ionophores. When optimizing the filling solution in a liquid contact ISE, it was possible to achieve a lower limit of detection of approximately 8 nM according to the IUPAC definition. Last, the new ionophores were also evaluated in four solid-contact (SC) designs leading to Nernstian response, with the best response noted with a SC electrode utilizing a gold substrate, a poly(3-octylthiophene) (POT) ion-to-electron transducer and a poly(methyl methacrylate)–poly(decyl methacrylate) (PMMA–PDMA) co-polymer membrane. This electrode exhibited a slope of 58.4 mV decade

  6. Thallium Flux Assay for Measuring the Activity of Monovalent Cation Channels and Transporters.

    Science.gov (United States)

    Weaver, C David

    2018-01-01

    Monovalent cation channels are critically important for physiological processes ranging from the control of neuronal excitability to the maintenance of solute balance. Mutations in these channels are associated with a multiplicity of diseases and monovalent cation channel-modulating drugs are used as therapeutics. Techniques that allow the measurement of the activity of these ion channels are useful for exploring their many biological roles as well as enabling the discovery and characterization of ion channel modulators for the purposes of drug discovery. Although there are numerous techniques for measuring the activity of monovalent cation channels, the thallium flux assay technique is a widely used fluorescence-based approach. Described herein is a method for using the thallium-flux technique for detecting and quantifying the activity of small-molecule potassium channel modulators in 384-well plates.

  7. Comparative studies on right ventricular pressure and volume overloading by thallium-201 myocardial scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Owada, K.; Tsukahara, Y.; Kijima, M.; Miyazaki, Y.; Ono, K. (Fukushima Medical Coll. (Japan))

    1982-03-01

    Thallium-201 myocardial scintigraphy was performed in 44 patients with various heart diseases including mitral stenosis, atrial septal defect, primary pulmonary hypertension, and left atrial myxoma. The morphological findings of right ventricular (RV) free wall on the scintigram and RV/IVS (interventricular septum) uptake ratio of the images obtained from the left anterior oblique projection were studied in the patients with RV pressure or volume overloading.

  8. Tunable frequency-stabilization of UV laser using a Hallow-Cathode Lamp of atomic thallium

    CERN Document Server

    Chen, Tzu-Ling; Shy, Jow-Tsong; Liu, Yi-Wei

    2013-01-01

    A frequency-stabilized ultraviolet laser system, locked to the thallium resonant transition of 377.5 nm, was demonstrated using a novel bichromatic spectroscopy technique for tuning the zero-crossing laser-lock point. The atomic thallium system is a promising candidate in atomic parity violation and permanent electric dipole moment experiments, and its 377.5 nm 6P1/2->7S1/2 transition is important for thallium laser cooling and trapping experiment. The pressure shift, owing to the high pressure bu?er gas of the hollow-cathode lamp, was observed using an atomic beam resonance as reference. Such a shift was corrected by adjusting the peak ratio of the two Doppler-free saturation pro?les resulted from two pumping beams with a 130 MHz frequency di?erence. The resulted frequency stability of the ultraviolet laser is ?0.5 MHz at 0.1 sec integration time. This scheme is compact and versatile for stabilizing UV laser systems, which acquire a sub-MHz stability and frequency tunability.

  9. Detection of human collateral circulation by vasodilation-thallium-201 tomography

    Energy Technology Data Exchange (ETDEWEB)

    Nienaber, C.A.; Salge, D.; Spielmann, R.P.; Montz, R.; Bleifeld, W. (University Hospital Eppendorf, Hamburg (Germany, F.R.))

    1990-04-15

    Coronary arteriolar vasodilation may provoke redistribution of flow to collateral-dependent jeopardized myocardium. To assess the physiologic significance of collaterals, 80 consecutive post-infarction patients (age 58 +/- 8 years) underwent vasodilation-redistribution thallium-201 tomographic imaging after administration of 0.56 mg of intravenous dipyridamole/kg body weight. Circumferential profile analysis of thallium-201 uptake and redistribution in representative left ventricular tomograms provided quantitative assessment of transient and fixed defects and separation between periinfarctional and distant inducible hypoperfusion. Tomographic perfusion data were correlated to wall motion and collateral circulation between distinct anatomic perfusion territories. Patients were grouped according to presence (59%) or absence (41%) of angiographically visible collateral channels to jeopardized myocardium. In the presence of collaterals, distant reversible defects were larger than in absence of collaterals (p less than 0.05); the extent of combined periinfarctional and distant redistribution was also larger in collateralized patients (p less than 0.025), whereas the size of the persistent perfusion defect was similar in both groups. By prospective analysis the tomographic perfusion pattern of combined periinfarctional and distant redistribution revealed a sensitivity of 85% and a specificity of 78% for the detection of significant collateral circulation in this group of patients. Thus, using the exhausted flow reserve as a diagnostic tool, vasodilation-thallium-201 tomography has the potential to identify and quantitate collateralized myocardium in post-infarction patients and may guide diagnostic and therapeutic decision-making.

  10. Thallium and manganese complexes involved in the luminescence emission of potassium-bearing aluminosilicates

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Gonzalez, Miguel A., E-mail: miguel.gomez@mncn.csic.es [Museo Nacional de Ciencias Naturales, CSIC, Jose Gutierrez Abascal 2, Madrid E-28006 (Spain); Garcia-Guinea, Javier, E-mail: guinea@mncn.csic.es [Museo Nacional de Ciencias Naturales, CSIC, Jose Gutierrez Abascal 2, Madrid E-28006 (Spain); Garrido, Fernando, E-mail: fernando.garrido@mncn.csic.es [Museo Nacional de Ciencias Naturales, CSIC, Jose Gutierrez Abascal 2, Madrid E-28006 (Spain); Townsend, Peter D., E-mail: pdtownsend@gmail.com [School of Science and Technology, University of Sussex, Brighton BN1 9QH (United Kingdom); Marco, Jose-Francisco, E-mail: jfmarco@iqfr.csic.es [Instituto de Química-Física Rocasolano, CSIC, Calle Serrano 119, Madrid E-28006 (Spain)

    2015-03-15

    The luminescence emission at 285 nm in natural K-feldspar has been studied by Russian groups and associated with thallium ions in structural positions of K{sup +} sites as artificially thallium-doped feldspars display the same emission band. Here attention is focussed on spectra of CL emission bands centered near 285 and 560 nm from paragenetic adularia, moscovite and quartz micro-inclusions. With accesorial thallium they show clear resemblances to each other. Associated sedimentary and hydrothermal aluminosilicate samples collected from Guadalix (Madrid, Spain) were analyzed with a wide range of experimental techniques including Environmental Scanning Electron Microscopy (ESEM) with an attached X-Ray Energy-Dispersive Spectrometer (EDS) and a cathodoluminescence probe (CL) and Electron Probe Microanalysis (EPMA), X-Ray Fluorescence Spectrometry (XRF), Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES), Differential and Thermogravimetric Analyses (DTA-TG), radioluminescence (RL), Mössbauer spectroscopy and X-Ray Photoelectron Spectrometry (XPS). The luminescence emission bands at 285 and 560 nm seem to be associated with hydrous thallium–manganese complexes bonded to potassium-bearing aluminosilicates since various minerals such as K-feldspar, moscovite and quartz micro-inclusions display similar CL spectra, accesorial thallium and hydroxyl groups. The presence of iron introduces a brown color which is attributed to submicroscopic iron oxides detectable in the optical and chemical microanalysis, but this does not contribute to the luminescence emission. The XPS Mn 2p spectrum of the adularia sample at room temperature is composed of a spin–orbit doublet plus clear shake-up satellite structure ∼4 eV above the main photoemision lines and is consistent with Mn{sup 2+} in good agreement with the observed luminescence emission at 560 nm for aluminosilicates produced by a {sup 4}T1({sup 4}G)→{sup 6}A1({sup 6}S) transition in tetrahedrally

  11. Diagnostic value of 123I-phenylpentadecanoic acid (IPPA) metabolic and thallium 201 perfusion imaging in stable coronary artery disease.

    Science.gov (United States)

    Walamies, M; Turjanmaa, V; Koskinen, M; Uusitalo, A

    1993-08-01

    The diagnostic value of 123I-phenylpentadecanoic acid (IPPA) metabolic cardiac imaging was studied in a group (n = 29) of patients with angiographically confirmed CAD using single photon emission computed tomography (SPECT). A symptom-limited exercise test was first done with IPPA, and 2 days later with thallium. Medications were not withheld during testing. Fourteen healthy control subjects participated in parallel IPPA and 15 in thallium tests. Data acquisition and output were comparable in the two imaging modalities. By testing various relatively simple criteria for abnormality we found that the semiquantitative interpretation was more accurate than the visual readings. The best compromise of accuracy with the scored criteria consisted of a sensitivity of 86% and a specificity of 86%, obtained with IPPA polar tomograms (mild exercise defect) and a sensitivity of 86% and a specificity of 80% obtained with thallium (regionally decreased washout). With visual interpretation alone, a sensitivity of 83% and a specificity of 71% was detected with IPPA (mild exercise defect) and 72% and 73%, respectively, with thallium (partial reversibility). The sensitivity of the exercise ECG alone was 62%. The results of this study imply that IPPA imaging could be a rational, uncomplicated clinical method for non-invasive diagnosis of CAD. The diagnostic ability of IPPA is at least as good as that of thallium, and it is possible to use them in succession.

  12. Dilatation of the left ventricular cavity on dipyridamole thallium-201 imaging: A new marker of triple-vessel disease

    Energy Technology Data Exchange (ETDEWEB)

    Takeishi, Y.; Tono-oka, I.; Ikeda, K.; Komatani, A.; Tsuiki, K.; Yasui, S. (Yamagata Univ. School of Medicine (Japan))

    1991-02-01

    To investigate the significance and mechanism of dilatation of the left ventricular cavity on dipyridamole thallium-201 imaging, we performed both dipyridamole thallium-201 imaging and dipyridamole radionuclide angiography on 83 patients with known angiograms. The dipyridamole/delayed ratio of the left ventricular dimension from the thallium-201 image was defined as the left ventricular dilatation ratio (LVDR). An LVDR greater than the mean + two standard deviations in patients without coronary artery disease was defined as abnormal. Twenty-two of 83 patients showed an abnormal LVDR, and 18 of the 22 patients (82%) had triple-vessel disease. By defect and washout analysis, the sensitivity and specificity for correctly identifying the patients as having triple-vessel disease was 72% and 76%, respectively, whereas LVDR had a sensitivity of 72% and a specificity of 93%. When LVDR was used in combination with the defect and washout criteria, sensitivity increased to 84% without a loss of specificity. In those 22 patients with abnormal LVDRs, end-diastolic volume measured by radionuclide angiography did not change after dipyridamole infusion. Dilatation of the left ventricular cavity on dipyridamole thallium-201 imaging reflected relative subendocardial hypoperfusion induced by dipyridamole rather than actual chamber enlargement. The LVDR was moderately sensitive and highly specific for triple-vessel disease and provided complementary information to dipyridamole thallium-201 imaging.

  13. A preliminary investigation and evaluation of the thallium environmental impacts of the unmined Xiangquan thallium-only deposit in Hexian, China

    Science.gov (United States)

    Zhou, Taofa; Fan, Yu; Yuan, Feng; Cooke, David; Zhang, Xin; Li, Liangjun

    2008-03-01

    The Xiangquan Thallium-only deposit in Hexian, east China is a newly found near-surface and unmined shallow-seated thallium deposit. The 250t Tl deposit is hosted in Lower Ordovician Lunshan Group as lenticular and confined by northeast F1, F2 faults. The metallic minerals are dominated by pyrite, more than 95% Tl occurs in pyrite as tiny individual grains or as ‘‘invisible thallium”. Tl and other trace elements pollution in ecosystems such as soils, surface and ground waters and water sediments, plants and crops, and animal and human beings in Xiangquan near the Tl ore deposit have been investigated and evaluated. Results show that Tl as well as As and Sb in ecosystems in Xiangquan around the deposit have enriched, they came from Tl-pyrite in the ore bodies and in the parent rocks of weathered soils on top of the ore bodies and went into the nearby ecosystems through weathering, leaching and dissolving. In 2 km2 around the Xiaolongwang Mountain where the Tl ore deposit seated, soils, vegetables, crops have been polluted or heavily polluted by Tl, As and Sb. Farmlands near the ore body are not fit to grow vegetables and crops. Thermal Spring water in Xiangquan town and pond water close to the Tl deposit are not potable. Tl also enriches in human hair and urinate of villagers who live close to the Tl deposit. Even through the Tl-only deposit has put clear environmental impacts on the local environment and ecosystems around it, no serious consequences of Tl pollution have so far taken place due to unmining of the Tl deposit as well as the screen effect of the silicficious breccia cap on top of it. All this work adds new knowledge to understand Tl behavior in unmined Tl deposit, and also benefit to the local environmental protection and the future mineral resources exploration.

  14. {sup 201}Thallium SPECT, accuracy in astrocytoma diagnosis and treatment evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kaellen, K

    1999-10-01

    The aims of the studies included in this thesis were: - to investigate the reliability of {sup 201}Thallium single photon emission computed tomography. Tl SPECT for preoperative diagnosis and histological staging of malignant astrocytomas in comparison with CT; - to develop a method for quantification of cerebral thallium uptake, and to evaluate the quantitative measurement in comparison with CT, for astrocytoma treatment follow-up purposes; - to compare quantitative Tl SPECT and proton magnetic resonance spectroscopy (H-MRS) with conventional MR imagingfor astrocytoma monitoring, and to evaluate associations between change of morphological tumour characteristics during treatment and changes of cerebral thallium uptake and metabolic ratios. Results and conclusions: - High TI-index, calculated as a ratio comparing tumour uptake to uptake in the contralateral hemisphere, is an indicator of highly malignant astrocytoma. Differentiation between the high-grade astrocytomas, the low-grade astrocytomas, and infectious lesions is only partial, with an overlap of Tl-indexes between these groups. High-grade astrocytomas that do not show contrast enhancement on CT, and astrocytomas with central necrosis and moderate ring-enhancement, tend to be underestimated when evaluated by Tl-index calculation. Tl SPECT is not a reliable method for non-invasive tumour staging among the group of highly malignant astrocytomas. - Quantification of cerebral TI-uptake, defining the volume of viable tumour tissue, is a new method for astrocytoma chemotherapy monitoring. Results suggest that the method provides prognostic information, and information of treatment efficacy, at an earlier stage than CT. - We did not find a higher accuracy of quantitative Tl SPECT than of MR for monitoring purposes and our results indicated that treatment induced MR changes were interrelated with TI-uptake variations. - Multi-voxel H-MRS was difficult to apply for astrocytoma treatment monitoring, due to the

  15. A Novel Ion - selective Polymeric Membrane Sensor for Determining Thallium(I) With High Selectivity

    Science.gov (United States)

    Kassim, Anuar; Rezayi, Majid; Ahmadzadeh, Saeid; Rounaghi, Gholamhossein; Mohajeri, Masoomeh; Azah Yusof, Noor; Tee, Tan Wee; Yook Heng, Lee; Halim Abdullah, Abd

    2011-02-01

    Thallium is a toxic metal that introduced into the environment mainly as a waste from the production of zinc, cadmium, and lead and by combustion of coal. Thallium causes gastrointestinal irritation and nerve damage when people are exposed to it for relatively short period of time. For long term, thallium has the potential to cause the following effects: change in blood chemistry, damage to liver, kidney, intestinal and testicular tissue, and hair loss. In this work a membrane was prepared by use of 4'-nitrobenzo -18-crown-6 (4'NB18C6) as an ion carrier, polyvinylchloride (PVC) as a matrix, and diocthylphetalate (DOP) as a plasticizer for making an ion selective electrode for measurement of Tl+ cation in solutions. The amount of 4'-nitrobenzo-18C6 and polyvinylchloride were optimized in the preparation of the membrane. The response of the electrode was Nernstian within the concentration range 1.0 × 10-8 to 1.0 × 10-1M. This sensor displays a drift in Nernstian response for this cation with increasing the amount of ionophore and decreasing the amount of polyvinylchloride.The results of potentiometric measurements showed that, this electrode also responses to Cu2+ Ni2+ and Pb2+ cations, but the electrode has a wider dynamic range and a lower detection limit to Tl+ cation. The effects of various parameters such as pH, different cations interferences, effect of the amount of ionophore and polyvinylchloride and time on response of the coated ion selective electrode were investigated. Finally the constructed electrode was used in complexometric and precipitation titrations of Tl+ cation with EDTA and KBr, respectively. The response of the fabricated electrode at concentration range from 1.0 × 10-8 to 1.0 × 10-1M is linear with a Nernstian slope of 57.27 mV.

  16. Oxidative stress and DNA damage in broad bean (Vicia faba L.) seedlings induced by thallium.

    Science.gov (United States)

    Radić, Sandra; Cvjetko, Petra; Glavas, Katarina; Roje, Vibor; Pevalek-Kozlina, Branka; Pavlica, Mirjana

    2009-01-01

    Thallium (Tl) is a metal of great toxicological concern because it is highly toxic to all living organisms through mechanisms that are yet poorly understood. Since Tl is accumulated by important crops, the present study aimed to analyze the biological effects induced by bioaccumulation of Tl in broad bean (Vicia faba L.) as well as the plant's antioxidative defense mechanisms usually activated by heavy metals. Thallium toxicity was related to production of reactive oxygen species in leaves and roots of broad bean seedlings following short-term (72 h) exposure to thallium (I) acetate (0, 0.5, 1, 5, and 10 mg/L) by evaluating DNA damage and oxidative stress parameters as well as antioxidative response. The possible antagonistic effect of potassium (K) was tested by combined treatment with 5 mg/L of Tl (Tl+) and 10 mg/L of potassium (K+) acetate. Accumulation of Tl+ in roots was 50 to 250 times higher than in broad bean shoots and was accompanied by increase in dry weight and proline. Despite responsive antioxidative defense (increased activities of superoxide dismutase, ascorbate peroxidase, and pyrogallol peroxidase), Tl+ caused oxidative damage to lipids and proteins as evaluated by malondialdehyde and carbonyl group levels, and induced DNA strand breaks. Combined treatment caused no oxidative alternations to lipids and proteins though it induced DNA damage. The difference in Tl-induced genotoxicity following both acellular and cellular exposure implies indirect DNA damage. Results obtained indicate that oxidative stress is involved in the mechanism of Tl toxicity and that the tolerance of broad bean to Tl is achieved, at least in part, through the increased activity of antioxidant enzymes.

  17. Thallium Intoxication Treated with Long-Term Hemodialysis, Forced Diuresis and Prussian Blue

    DEFF Research Database (Denmark)

    Larsen, Elfinn; Solgaard, Per Bent; Freund, L. Gade

    1978-01-01

    A 56 yr old woman, who ingested 2 g of thallium sulfate, was successfully treated with long-term hemodialysis for 200 h during 10 days, combined with forced diuresis and Prussian blue. The effect of the artificial kidney dialysis was determined by repeated analysis of the Tl concentration...... in the dialysis bath and in blood samples. During the 1st 120 h of hemodialysis, 143 mg of Tl was eliminated via the artificial kidney and 110 mg via the urinary tract. The present case of acute Tl intoxication is the 1st in which long-term hemodialysis has been used in the acute phase...

  18. Experimental excitation functions of deuteron induced reactions on natural thallium up to 50 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Adam Rebeles, R., E-mail: radamreb@vub.ac.be [Cyclotron Laboratory, Vrije Universiteit Brussel, B-1090 Brussels (Belgium); Van den Winkel, P.; Hermanne, A. [Cyclotron Laboratory, Vrije Universiteit Brussel, B-1090 Brussels (Belgium); Tarkanyi, F.; Takacs, S. [Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen H-4026 (Hungary)

    2012-10-01

    Excitation functions of deuteron induced reactions on natural thallium leading to the formation of {sup 204m,203m2+m1+g,202m,201m+g,200}Pb and {sup 202,201m+g,200m+g}Tl isotopes were determined up to 50 MeV. The cross sections were measured by an activation technique using stacked foil irradiation. The excitation functions of the investigated reactions are compared with data reported in literature and also with the theoretical results of TALYS nuclear reaction code. From the measured cross section data, the thick target yield for the medical interesting {sup 203}Pb isotope is calculated.

  19. Application of Hyphenated Techniques in Speciation Analysis of Arsenic, Antimony, and Thallium

    Science.gov (United States)

    Michalski, Rajmund; Szopa, Sebastian; Jabłońska, Magdalena; Łyko, Aleksandra

    2012-01-01

    Due to the fact that metals and metalloids have a strong impact on the environment, the methods of their determination and speciation have received special attention in recent years. Arsenic, antimony, and thallium are important examples of such toxic elements. Their speciation is especially important in the environmental and biomedical fields because of their toxicity, bioavailability, and reactivity. Recently, speciation analytics has been playing a unique role in the studies of biogeochemical cycles of chemical compounds, determination of toxicity and ecotoxicity of selected elements, quality control of food products, control of medicines and pharmaceutical products, technological process control, research on the impact of technological installation on the environment, examination of occupational exposure, and clinical analysis. Conventional methods are usually labor intensive, time consuming, and susceptible to interferences. The hyphenated techniques, in which separation method is coupled with multidimensional detectors, have become useful alternatives. The main advantages of those techniques consist in extremely low detection and quantification limits, insignificant interference, influence as well as high precision and repeatability of the determinations. In view of their importance, the present work overviews and discusses different hyphenated techniques used for arsenic, antimony, and thallium species analysis, in different clinical, environmental and food matrices. PMID:22654649

  20. Evaluation of myocardial abnormalities in collagen diseases by thallium-201 myocardial scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Yamano, Shigeru; Kagoshima, Tadashi; Sugihara, Kiyotaka (Nara Medical Univ., Kashihara (Japan)) (and others)

    1993-12-01

    This study was performed to evaluate myocardial abnormalities in patients with collagen diseases by exercise and rest thallium-201 myocardial scintigrams. A total of 65 patients without ischemic ECG changes, consisting of 18 with systemic lupus erythematosus (SLE), 18 with polymyositis (PM), 8 with progressive systemic sclerosis (PSS), and 21 with Sjoegren's syndrome (SjS), was enrolled in this study. Reversible exercise-induced defects scintigraphically suggesting myocardial ischemia were noted in 8 cases of SLE, 4 cases of PM, 4 cases of PSS, and 3 cases of SjS. Nineteen patients had exercise-induced defects and underwent cardiac catheterization, 8 of whom had normal coronary angiograms. Fixed hypoperfusion areas were observed in one case of SLE, 6 cases of PM and 3 cases of SjS. Rest thallium-201 myocardial scintigram disclosed hypoperfusion areas which were not induced by exercise in 2 cases of SLE, 3 cases of PM, one case of PSS and 5 cases of SjS. Echocardiogram showed no significant differences in ejection fraction and % fractional shortening between the disease groups and healthy control group. These findings suggest that patients with collagen diseases have abnormalities of coronary circulation at the level of the intramural vasculature before cardiac function impairment, myocardial fibrosis and functional abnormalities at the cell membrane. (author).

  1. Follow-up Thallium-201 scintigraphy after mantle field radiotherapy for Hodgkin's disease

    Energy Technology Data Exchange (ETDEWEB)

    Pierga, J.Y.; Girinski, T.; Henry-Amar, M. (Institut Gustave Roussy, Villejuif (France)); Maunoury, C.; Valette, H.; Tchernia, G.; Desgrez, A. (Centre Hospitalier de Bicetre, Le Kremlin-Bicetre (France)); Socie, G. (Institut Gustave Roussy, Villejuif (France) Hopital St Louis, Paris (France)); Cosset, J.M. (Institut Gustave Roussy, Villejuif (France) Institut Curie, Paris (France))

    1993-04-02

    Assessment of the long-term cardiac effects of mediastinal radiotherapy for Hodgkin's disease, by Thallium scintigraphy. 32 patients (14 males and 18 females) who underwent mantle field radiotherapy for Hodgkin's disease were included in this study. Twenty patients received 4 fractions of 2.5 Gy per week and 12, five fraction of 2 Gy per week, delivered on alternate days. All the patients, except three, performed exercise testing electrocardiogram and Thallium-201 tomoscintigraphy. The average time interval from completion of treatment to the study was 7 years (range 3--13 years). No patients had clinical symptoms of cardiac disease. Mean age at the time of the study was 35 years (range 23--48 years). Two electrocardiograms revealed left bundle branch block and the patients were excluded from the study. Only one out of 27 exercise electrocardiograms was abnormal in a patient with mitral valve prolapse, who was also excluded from the study. Twenty-six scintigraphies were evaluable. Twenty-two (85%) were clearly abnormal with partial or complete redistribution on delayed images. The anterior region was affected in 19 of these cases (86%). Four explorations were undoubtedly normal. Coronary angiography was not performed for ethical reasons in these asymptomatic patients. Despite possible false positive tests, the high rate of abnormality (85%) in this small series is striking. These preliminary data justify larger studies and a close long-term follow-up of these patients. 24 refs., 1 fig., 2 tabs.

  2. Thallium occurrence and partitioning in soils and sediments affected by mining activities in Madrid province (Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Gonzalez, M.A.; Garcia-Guinea, J. [National Museum of Natural Sciences, CSIC, Jose Gutierrez Abascal 2, 28006 Madrid (Spain); Laborda, F. [Group of Analytical Spectroscopy and Sensors Group, Institute of Environmental Sciences, University of Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza (Spain); Garrido, F., E-mail: fernando.garrido@mncn.csic.es [National Museum of Natural Sciences, CSIC, Jose Gutierrez Abascal 2, 28006 Madrid (Spain)

    2015-12-01

    Thallium (Tl) and its compounds are toxic to biota even at low concentrations but little is known about Tl concentration and speciation in soils. An understanding of the source, mobility, and dispersion of Tl is necessary to evaluate the environmental impact of Tl pollution cases. In this paper, we examine the Tl source and dispersion in two areas affected by abandoned mine facilities whose residues remain dumped on-site affecting to soils and sediments of natural water courses near Madrid city (Spain). Total Tl contents and partitioning in soil solid phases as determined by means of a sequential extraction procedure were also examined in soils along the riverbeds of an ephemeral and a permanent streams collecting water runoff and drainage from the mines wastes. Lastly, electronic microscopy and cathodoluminescence probe are used as a suitable technique for Tl elemental detection on thallium-bearing phases. Tl was found mainly bound to quartz and alumino-phyllosilicates in both rocks and examined soils. Besides, Tl was also frequently found associated to organic particles and diatom frustules in all samples from both mine scenarios. These biogenic silicates may regulate the transfer of Tl into the soil-water system. - Highlights: • Abandoned mine residues are Tl sources in soils of Madrid catchment area. • Tl was associated to quartz and aluminosilicates in both rocks and soils. • Tl was frequently found associated to organic particles and diatom frustules. • Cathodoluminescence is a suitable technique for Tl detection on soils and rocks.

  3. [Detecting Thallium in Water Samples using Dispersive Liquid Phase Microextraction-Graphite Furnace Atomic Absorption Spectroscopy].

    Science.gov (United States)

    Zhu, Jing; Li, Yan; Zheng, Bo; Tang, Wei; Chen, Xiao; Zou, Xiao-li

    2015-11-01

    To develope a method of solvent demulsification dispersive liquid phase microextraction (SD-DLPME) based on ion association reaction coupled with graphite furnace atomic absorption spectroscopy (GFAAS) for detecting thallium in water samples. Methods Thallium ion in water samples was oxidized to Tl(III) with bromine water, which reacted with Cl- to form TlCl4-. The ionic associated compound with trioctylamine was obtained and extracted. DLPME was completed with ethanol as dispersive solvent. The separation of aqueous and organic phase was achieved by injecting into demulsification solvent without centrifugation. The extractant was collected and injected into GFAAS for analysis. With palladium colloid as matrix modifier, a two step drying and ashing temperature programming process was applied for high precision and sensitivity. The linear range was 0.05-2.0 microg/L, with a detection limit of 0.011 microg/L. The relative standard derivation (RSD) for detecting Tl in spiked water sample was 9.9%. The spiked recoveries of water samples ranged from 94.0% to 103.0%. The method is simple, sensitive and suitable for batch analysis of Tl in water samples.

  4. The learning machine in quantitative chemical analysis : Part I. Anodic Stripping Voltammetry of Cadmium, Lead and Thallium

    NARCIS (Netherlands)

    Bos, M.; Jasink, G.

    1978-01-01

    The linear learning machine method was applied to the determination of cadmium, lead and thallium down to 10-8 M by anodic stripping voltammetry at a hanging mercury drop electrode. With a total of three trained multicategory classifiers, concentrations of Cd, Pb and Tl could be predicted with an

  5. Thallium chloride 201Tl combined with single photon emission computed tomography (SPECT) in the evaluation of vestibular schwannoma growth

    DEFF Research Database (Denmark)

    Charabi, Samih Ahmed; Lassen, N A; Thomsen, J

    1997-01-01

    Thallium chloride 201Tl combined with SPECT was performed in a series of 29 patients with neuroradiological evidence of vestibular schwannoma (VS). The relative tumor uptake (U) and relative tumor concentration (C) of the radiotracer 201Tl was determined, and the cerebellum served as a reference...

  6. Bis(2-mercapto-1-R-imidazolyl)hydroborato complexes of aluminium, gallium, indium and thallium: compounds possessing gallium-gallium bonds and a trivalent thallium alkyl.

    Science.gov (United States)

    Yurkerwich, Kevin; Coleman, Fergal; Parkin, Gerard

    2010-08-14

    The reactions of bis(mercaptoimidazolyl)hydroborato derivatives [Bm(R)]M' (R = Me, Bu(t); M' = Li, Na, Tl) with MX(3) trihalides of aluminium, gallium and indium yield both 1:1 and 2:1 complexes of the types [Bm(R)]MX(2) and [Bm(R)](2)MX, respectively. Structurally characterized examples of the [Bm(R)]MX(2) series include [Bm(Me)]AlCl(2), [Bm(Me)]GaI(2), [Bm(Me)]InI(2), [Bm(Bu(t))]AlCl(2) and [Bm(Bu(t))]GaX(2) (X = Cl, Br, I), while structurally characterized examples of the [Bm(R)](2)MX series include [Bm(Bu(t))](2)InX (X = Cl, Br, I). In addition to the halide complexes, the trivalent dimethyl thallium complex [Bm(Bu(t))]TlMe(2) has been synthesized via the reaction of [Bm(Bu(t))]Tl with Me(2)TlCl. The reactions of [Bm(R)]M' with the monovalent halides, "GaI", InCl and InI, result in disproportionation. In the case of indium, the mononuclear complexes [Bm(Bu(t))](2)InI and [Bm(Bu(t))]InCl(kappa(2)-mim(Bu(t))) are obtained, whereas for gallium, dinuclear compounds that feature Ga-Ga bonds, namely [Bm(R)](GaI)(GaI)[Bm(R)] (R = Me, Bu(t)) have been isolated.

  7. Thallium stress testing does not predict cardiovascular risk in diabetic patients with end-stage renal disease undergoing cadaveric renal transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Holley, J.L.; Fenton, R.A.; Arthur, R.S. (Univ. of Pittsburgh, PA (USA))

    1991-05-01

    This study assessed the usefulness of thallium stress testing as a predictor of perioperative cardiovascular risk in diabetic patients with end-stage renal disease undergoing cadaveric renal transplantation. Demographic factors influencing the exercise performance in these patients were also examined. The medical records of 189 consecutive patients with diabetic nephropathy who were evaluated for cadaveric renal transplantation were reviewed. Thallium stress testing was the initial examination of cardiovascular status in 141 patients. An adequate examination was one in which at least 70% of maximum heart rate was achieved. A thallium stress test was normal if there were no ST segment depressions on the electrocardiogram and no perfusion abnormalities on the thallium scan. Forty-four patients underwent cardiac catheterization as the initial evaluation (Group C) and four patients underwent transplantation without a formal cardiovascular evaluation (Group D). Sixty-four of the 141 patients undergoing thallium stress testing had an adequate and normal examination (Group A). The incidence of perioperative cardiac events in this group was 2%. Seventy-seven patients (Group B) had an abnormal (n = 41) or an inadequate (n = 36) thallium stress test and most (n = 61) then underwent coronary angiography. The use of beta-blockers was the only predictor of an abnormal or inadequate thallium stress test. Forty-three percent of patients with inadequate or abnormal thallium stress tests had significant coronary artery disease on cardiac catheterization. The perioperative risk of cardiac events was not different in Group A versus Groups B, C, and D combined. Survival of Group A and B patients was not different but was significantly longer than that of Group C patients.

  8. Evaluation of thallium-201 scanning for detection of latent coronary artery disease

    Science.gov (United States)

    Johnson, P. C.; Leblanc, A.; Deboer, L.; Jhingran, S.

    1978-01-01

    The use of thallium imaging as a noninvasive method to accurately screen shuttle passengers for latent coronary artery disease was investigated. All radionuclide procedures were performed using an Anger type camera with a high resolution collimator. A minimum of 200,000 counts were collected for each image using a 20% window centered on the 69-83 keV X-rays. For the images obtained following injection with the patient at rest, the testing was begun 10 minutes after injection. Injections of TT during exercise were made at a point near the termination of the treadmill procedure as determined by either the appearance of ST segment changes on the electrocardiogram consistant with subendocardial ischemia, the appearance of angina-like chest pain in the patient or fatigue in the patient which required cessation of the test. The severity of heart disease was based on the medical history, physical exam, exercise electrocardiograms, chest X-rays and the coronary arteriogram.

  9. Thallium Analysis in Environmental Samples by Inductively Coupled Plasma Mass Spectrometry; Analisis de Talio en Muestras Ambientales por Espectrometria de Masas con Fuente de Plasma de Acoplamiento Inductivo

    Energy Technology Data Exchange (ETDEWEB)

    Higueras, I.; Fernandez, M.; Conde, E.; Gajate, A.

    2008-08-06

    Due to its high toxicity, thallium has been considered by the US Environmental Protection Agency as one of the priority pollutants to be controlled. While being a highly toxic element, thallium has been studied to a much lesser degree than other toxic elements, mainly because thallium is often undetected by classical analytical methods. Thallium is a rare and dispersed element that occurs mainly in sulfur-containing ores. Thus, it is a potential pollutant to surrounding environment, if Tl-rich mineral and/or their industrial wastes are not properly disposed. In this work an Inductively Coupled Plasma Mass Spectrometry analytical procedure has been developed in order to determine thallium in environmental solid samples and its application to the study of this element as a potential pollutant associated with natural and anthropogenic activities. The analytical procedure has been validated by the use of appropriate reference materials, and through the isotope dilution technique as a primary method of measurement. Finally, the developed procedure has been applied to several samples from a mining area, as one of the scenarios where thallium it is likely to occur. (Author) 87 refs.

  10. A Case-Control Study of Prenatal Thallium Exposure and Low Birth Weight in China.

    Science.gov (United States)

    Xia, Wei; Du, Xiaofu; Zheng, Tongzhang; Zhang, Bin; Li, Yuanyuan; Bassig, Bryan A; Zhou, Aifen; Wang, Youjie; Xiong, Chao; Li, Zhengkuan; Yao, Yuanxiang; Hu, Jie; Zhou, Yanqiu; Liu, Juan; Xue, Weiyan; Ma, Yue; Pan, Xinyun; Peng, Yang; Xu, Shunqing

    2016-01-01

    Thallium (Tl) is a highly toxic heavy metal widely present in the environment. Case reports have suggested that maternal exposure to high levels of Tl during pregnancy is associated with low birth weight (LBW), but epidemiological data are limited. This study was designed to evaluate whether prenatal Tl exposure is associated with an increased risk of LBW. This case-control study involving 816 study participants (204 LBW cases and 612 matched controls) was conducted in Hubei Province, China, in 2012-2014. Tl concentrations were measured in maternal urine collected at delivery, and associations with LBW were evaluated using conditional logistic regression. Higher maternal urinary Tl levels were significantly associated with increased risk of LBW [crude odds ratio (OR) = 1.52; 95% CI: 1.00, 2.30 for the highest vs. lowest tertile], and the association was similarly elevated after adjustment for potential confounders (adjusted OR = 1.90; 95% CI: 1.01, 3.58 for the highest vs. lowest tertile). Stratified analyses showed slightly higher risk estimates for LBW associated with higher Tl levels for mothers case-control study to investigate the association between prenatal Tl exposure and LBW. The results suggest that prenatal exposure to high levels of Tl may be associated with an increased risk of LBW. Xia W, Du X, Zheng T, Zhang B, Li Y, Bassig BA, Zhou A, Wang Y, Xiong C, Li Z, Yao Y, Hu J, Zhou Y, Liu J, Xue W, Ma Y, Pan X, Peng Y, Xu S. 2016. A case-control study of prenatal thallium exposure and low birth weight in China. Environ Health Perspect 124:164-169; http://dx.doi.org/10.1289/ehp.1409202.

  11. Evaluation of myocardial abnormalities in patients with collagen diseases by thallium-201 myocardial scintigram

    Energy Technology Data Exchange (ETDEWEB)

    Yamano, Shigeru (Nara Medical Univ., Kashihara (Japan))

    1992-08-01

    This study was performed to evaluate myocardial lesions in patients with collagen diseases by rest and exercise thallium-201 myocardial scintigraphies. A total of 76 patients without ischemic ECG changes, consisting of 27 cases of systemic lupus erythematosus (SLE), 17 cases of polymyositis or dermatomyositis (PM[center dot]DM), 11 cases of progressive systemic sclerosis (PSS), and 21 cases of Sjoegren's syndrome (SjS), were enrolled in this study. Reversible exercise-induced defects suggesting myocardial ischemia were noted in 12 cases of SLE, 5 cases of PM[center dot]DM, 3 cases of PSS, and 3 cases of SjS. Of the 23 patients who had exercise-induced defects, 9 patients showed normal coronary angiograms by cardiac catheterization. Fixed hypoperfusion areas were observed in 5 cases of SLE, 6 cases of PM[center dot]DM, 4 cases of PSS and 3 cases of SjS. Rest thallium-201 myocardial scintigraphy disclosed hypoperfusion areas, which were not induced by exercise, in 1 case of SLE, 4 cases of PM[center dot]DM, 1 case of PSS and 5 cases of SjS. Endomyocardial biopsy was performed on 20 patients. Myocardial lesions in PM[center dot]DM and PSS were more severe and wide spread than in SLE. Ejection fraction and fractional shortening evaluated by echocardiography had no significant differences between each disease group and the healthy control group. These findings suggest that patients with collagen diseases show the presence of abnormalities of coronary circulation at the level of the intramyocardial vasculature in the stage before impairment of cardiac function, myocardial fibrosis and functional abnormalities of the cell membrane level that were not dependent on myocardial ischemia. (author).

  12. Development and Applications of Thallium isotopes: a new proxy tracking the extent of manganese oxide burial

    Science.gov (United States)

    Owens, J. D.; Nielsen, S.; Ostrander, C.; Peterson, L. C.; Anbar, A. D.

    2015-12-01

    Thallium (Tl) isotopes are a new and potential powerful paleoredox proxy with the possibility to track bottom water oxygen conditions based on the burial flux of manganese oxides. Thallium has a residence time of ~20 thousand years, which is long enough to render modern oxic seawater conservative with respect to concentration and isotopes. The isotopic signature of Tl in the global ocean is driven mainly by two outputs (1) adsorption onto manganese oxides and (2) low temperature oceanic crust alteration. Importantly, the isotopic inputs of Tl are all nearly the same value; thus, the isotopic composition and flux of the outputs almost exclusively set the seawater signature. For relatively short term redox events it is reasonable to assume that the dominant isotope fractionation process is associated with manganese oxide precipitation because low temperature alteration is controlled by long-term average ocean crust production rates. We present a broad range of modern samples that span several open ocean profiles combined with water column and sediment profiles from the permanently anoxic basins of the Black Sea and Cariaco Basins. The open ocean shows no variation in depth profiles that encompass most of the major water masses in the Atlantic and Southern Oceans. The anoxic basins, however, reveal Tl isotope signatures closer to their inputs, which is likely due to basinal restriction. The authigenic fraction of organic-rich sediments from the Black Sea and Cariaco Basin capture the Tl isotope value of the overlying water column, which shows that Tl isotopes could be applied as a faithful deep time redox proxy. For the first time, we will present new data showing that Tl isotopes is tracking bottom water ocean oxygenation. We are applying this isotope system to ancient samples, testing the spatial and temporal variability of ocean oxygenation coinciding with major biogeochemical events.

  13. Thallium myocardial tomoscintigraphy: detection of ischemia during weaning from mechanical ventilation in patients with chronic obstructive pulmonary disease. Tomoscintigraphie myocardique au thallium: detection de l'ischemie provoquee par le sevrage de la ventilation assistee chez le bronchiteux chronique

    Energy Technology Data Exchange (ETDEWEB)

    Andre, L.; Valette, H.; Obama, S.; Archambaud, F.; Richard, C.; Teboul, J.L.; Hebert, J.L.; Auzepy, P.; Desgrez, A. (Hopital de Bicetre, 94 - Le Kremlin-Bicetre (FR))

    1990-01-01

    In order to evidence myocardial ischemia-leading to ventricular dysfunction-during weaning from mechanical ventilation in patients with chronic obstructive pulmonary disease, thallium myocardial tomography and gated blood pool studies were performed in 9 patients during mechanical ventilation and during weaning from mechanical ventilation. During the latter, results of gated blood pool studies showed a diffuse homogeneous left ventricular dysfunction. A fixed lower thallium uptake in the septum than in the lateral wall was found with the quantitative analysis of myocardial tomograms. Partial volume effect is likely the cause of this septal defect. The hypothesis of a diffuse ischemia cannot be excluded; but, without the absolute quantification of tomographic data, it cannot be proven.

  14. Studies of photon spectra from a thallium-204 foil source as an aid to dosimetry and shielding

    CERN Document Server

    Francis, T M

    1976-01-01

    Beta ray foil sources incorporating nuclides such as thallium-204, promethium-147 and strontium-90 plus yttrium-90 ar increasingly used in industrial devices such as thickness gauges. These sources are so constructed that they give rise to complex photon spectra containing low energy Bremsstrahlung and X-rays characteristic of the constructional materials. The energy response of practical monitoring instruments is such that they are likely to underestimate the dose due to such spectra unless they are calibrated using appropriate spectra. This report describes a series of measurements carried out on a commercially available thallium-204 foil source and five commonly used shielding materials. The measurements made with a NaI(T1) spectrometer have been corrected for instrumental distortions to obtain the photon spectra in air. These spectra are presented and have been used to compute dose in air with the help of published data on mass energy-absorption coefficients. Also included in the report are data derived f...

  15. Septal myocardial perfusion imaging with thallium-201 in the diagnosis of proximal left anterior descending coronary artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Pichard, A.D.; Wiener, I.; Martinez, E.; Horowitz, S.; Patterson, R.; Meller, J.; Goldsmith, S.J.; Gorlin, R.; Herman, M.V.

    1981-07-01

    The use of myocardial perfusion imaging (MPI) to identify obstructive coronary disease of the left anterior descending coronary artery proximal to the first septal perforator (prox LAD) was studied in 60 patients. Perfusion of the septum and anteroapical areas with thallium-201 injected during exercise was compared to results of coronary arteriography. Septal MPI defect was found in 92.3% of patients with obstruction of the proximal LAD, 27.7% of patients with obstruction of LAD distal to first septal perforator, 0% in patients with obstructions involving right or circumflex arteries, and in 10.5% of patients without coronary disease. Anteroapical MPI defects were found with similar frequency in the three groups with obstructive coronary disease. Septal MPI defect had a sensitivity of 92.3% and specificity of 85.4% in the diagnosis of proximal LAD disease. Normal septal perfusion with thallium-201 virtually excluded proximal LAD disease.

  16. Usefulness of rest-redistribution thallium scan for the indication of PTCA in an interesting case with acute myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Chiba, Hiroshi; Nishimura, Tsunehiko; Mitani, Isao; Matsuo, Takeshi; Uehara, Toshiisa; Hayashida, Kohei; Sumiyoshi, Tetsuya; Haze, Kazuo

    1988-04-01

    A 72-year-old woman with acute myocardial infarction was received coronary thrombolytic therapy. After percutaneous transluminal coronary recanalization (PTCR), the stenosis of LAD became from 99 % to 90 %. Left ventriculogram showed dyskinesis of anterior wall in acute phase. After PTCR, she complained of postinfarctional angina. Thus, in order to evaluate the viability of anterior wall, serial thallium scintigraphy was performed at rest, which showed perfusion defect and redistribution of anterior wall. After percutaneous transluminal coronary angioplasty (PTCA), anterior wall motion became almost normal. The perfusion defect of anterior wall was also gradually disappeared. The serial thallium scintigraphy at rest is an useful method not only to evaluate the viability of myocardium in acute myocardial infarction, but also to follow the effect of PTCA.

  17. Rearrangement of beta,gamma-unsaturated esters with thallium trinitrate: synthesis of indans bearing a beta-keto ester moiety

    Directory of Open Access Journals (Sweden)

    Silva Jr. Luiz F.

    2006-01-01

    Full Text Available The rearrangement of beta,gamma-unsaturated esters, such as 2-(3,4-dihydronaphthalen-1-yl-propionic acid ethyl ester, with thallium trinitrate (TTN in acetic acid leads to 3-indan-1-yl-2-methyl-3-oxo-propionic acid ethyl ester in good yield, through a ring contraction reaction. The new indans thus obtained feature a beta-keto ester moiety, which would be useful for further functionalization.

  18. Formic acid electrooxidation on thallium-decorated shape-controlled platinum nanoparticles: an improvement in electrocatalytic activity

    OpenAIRE

    Busó-Rogero, Carlos; Perales-Rondón, Juan V.; Farias, Manuel J.S.; Vidal-Iglesias, Francisco J.; Solla-Gullón, José; Herrero, Enrique; Feliu, Juan M.

    2014-01-01

    Thallium modified shape-controlled Pt nanoparticles were prepared and their electrocatalytic activity towards formic acid electrooxidation was evaluated in 0.5 M sulfuric acid. The electrochemical and in situ FTIR spectroscopic results show a remarkable improvement in the electrocatalytic activity, especially in the low potential region (around 0.1–0.2 V vs. RHE). Cubic Pt nanoparticles modified with Tl were found to be more active than the octahedral Pt ones in the entire range of Tl coverag...

  19. Usefulness and limitations of thallium-201 myocardial scintigraphy in delineating location and size of prior myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Niess, G.S.; Logic, J.R.; Russell, R.O. Jr.; Rackley, C.E.; Rogers, W.J.

    1979-05-01

    Thirty-two patients were evaluated at a mean of 7 +- 2 months after infarction with a 12-lead ECG, resting /sup 201/Tl myocardial scintigram, biplane left ventriculogram, and coronary angiograms. From the left ventriculogram, asynergy was quantified as percent abnormally contracting segment (% ACS), the percent of end-diastolic circumference which was either akinetic or dyskinetic. Using a computerized planimetry system, we expressed /sup 201/Tl perfusion defects as a percentage of total potential thallium uptake. Of 21 patients with ECG evidence of prior transmural infarction, a /sup 201/Tl defect was present in 20, and angiographic asynergy was present in all 21. The site of prior infarction by ECG agreed with the /sup 201/T1 defect location in 24 of 32 patients and with site of angiographic asynergy in 23 of 32 patients. Scintigraphic defects were present in only four of 10 patients with ACS less than or equal to 6%, but scintigraphic defects were found in 20 of 22 patients with ACS > 6%. Thallium defect size correlated marginally with angiographic left ventricular ejection fraction but correlated closely with angiographic % ACS. Thallium defect size was similar among patients with one-, two-, or three-vessel coronary artery disease (greater than or equal to 70% stenosis), but thallium defect size was larger in patients with electrocardiographic evidence of transmural infarction or pulmonary capillary wedge pressure > 12 mm Hg. Thus, resting /sup 201/T1 myocardial scintigraphy is useful in localizing and quantifying the extent of prior myocardial infarction, but is insensitive to small infarcts (ACS < 6%).

  20. Determination of thallium at ultra-trace levels in water and biological samples using solid phase spectrophotometry.

    Science.gov (United States)

    Amin, Alaa S; El-Sharjawy, Abdel-Azeem M; Kassem, Mohammed A

    2013-06-01

    A new simple, very sensitive, selective and accurate procedure for the determination of trace amounts of thallium(III) by solid-phase spectrophotometry (SPS) has been developed. The procedure is based on fixation of Tl(III) as quinalizarin ion associate on a styrene-divinylbenzene anion-exchange resin. The absorbance of resin sorbed Tl(III) ion associate is measured directly at 636 and 830 nm. Thallium(I) was determined by difference measurements after oxidation of Tl(I) to Tl(III) with bromine. Calibration is linear over the range 0.5-12.0 μg L(-1) of Tl(III) with relative standard deviation (RSD) of 1.40% (n=10). The detection and quantification limits are 150 and 495 ng L(-1) using 0.6 g of the exchanger. The molar absorptivity and Sandell sensitivity are also calculated and found to be 1.31×10(7) L mol(-1)cm(-1) and 0.00156 ng cm(-2), respectively. The proposed procedure has been successfully applied to determine thallium in water, urine and serum samples. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. The efficient removal of thallium from sintering flue gas desulfurization wastewater in ferrous metallurgy using emulsion liquid membrane.

    Science.gov (United States)

    Yang, Li; Xiao, Jiangping; Shen, Yi; Liu, Xian; Li, Wensong; Wang, Weiyan; Yang, Yunquan

    2017-11-01

    The removal of thallium ions in flue gas desulfurization wastewater from ferrous metallurgic industry was studied by emulsion liquid membrane (ELM) method using 2-ethylhexyl phosphoric acid-2-ethylhexyl ester (P507) as carrier, aviation kerosene (AK) as organic solvent, polyisobutylene succinimide (T154) as surfactant, polyisobutylene (PIB) as additive, and sulfuric acid as internal reagent. Some important influence parameters such as concentrations of carrier, surfactant and stripping agent, agitation speed, extraction time, volume ratios of feed solution to emulsion phase and internal phase to membrane phase, and their effects on the removal efficiency of Tl in the ELM process were investigated and optimized. Under the optimum operating conditions of 2% of carrier, 5% of surfactant, 0.5 M of stripping agent, 350 rpm of agitation speed, 12.5:1 of volume ratio of feed solution to emulsion phase, and 3:1 volume ratio of membrane to internal phase, the maximum extraction efficiency of thallium reached 99.76% within 15-min reaction time. The ICP-MS analysis indicated that the thallium concentration in treated wastewater was below 5 μg/L and could meet the emission standard demand for industrial wastewater enacted by the local government of Hunan province of China. Meanwhile, the extraction of impurity ions calcium and magnesium in the ELM system was investigated. The result showed that an acidic environment would be in favor of the removal of Tl from calcium and magnesium contained in wastewater. Graphical abstract ᅟ.

  2. Thallium isotopes in metallurgical wastes/contaminated soils: A novel tool to trace metal source and behavior.

    Science.gov (United States)

    Vaněk, Aleš; Grösslová, Zuzana; Mihaljevič, Martin; Ettler, Vojtěch; Trubač, Jakub; Chrastný, Vladislav; Penížek, Vít; Teper, Leslaw; Cabala, Jerzy; Voegelin, Andreas; Zádorová, Tereza; Oborná, Vendula; Drábek, Ondřej; Holubík, Ondřej; Houška, Jakub; Pavlů, Lenka; Ash, Christopher

    2018-02-05

    Thallium (Tl) concentration and isotope data have been recorded for contaminated soils and a set of industrial wastes that were produced within different stages of Zn ore mining and metallurgical processing of Zn-rich materials. Despite large differences in Tl levels of the waste materials (1-500mgkg-1), generally small changes in ε205Tl values have been observed. However, isotopically lighter Tl was recorded in fly ash (ε205Tl∼-4.1) than in slag (ε205Tl∼-3.3), implying partial isotope fractionation during material processing. Thallium isotope compositions in the studied soils reflected the Tl contamination (ε205Tl∼-3.8), despite the fact that the major pollution period ended more than 30 years ago. Therefore, we assume that former industrial Tl inputs into soils, if significant, can potentially be traced using the isotope tracing method. We also suggest that the isotope redistributions occurred in some soil (subsurface) horizons, with Tl being isotopically heavier than the pollution source, due to specific sorption and/or precipitation processes, which complicates the discrimination of primary Tl. Thallium isotope analysis proved to be a promising tool to aid our understanding of Tl behavior within the smelting process, as well as its post-depositional dynamics in the environmental systems (soils). Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Thallium-isotopic compositions of euxinic sediments as a proxy for global manganese-oxide burial

    Science.gov (United States)

    Owens, Jeremy D.; Nielsen, Sune G.; Horner, Tristan J.; Ostrander, Chadlin M.; Peterson, Larry C.

    2017-09-01

    Thallium (Tl) isotopes are a new and potentially powerful paleoredox proxy that may track bottom water oxygen conditions based on the global burial flux of manganese oxides. Thallium has a residence time of ∼20 thousand years, which is longer than the ocean mixing time, and it has been inferred that modern oxic seawater is conservative with respect to both concentration and isotopes. Marine sources of Tl have nearly identical isotopic values. Therefore, the Tl sinks, adsorption onto manganese oxides and low temperature oceanic crust alteration (the dominant seawater output), are the primary controls of the seawater isotopic composition. For relatively short-term, ∼million years, redox events it is reasonable to assume that the dominant mechanism that alters the Tl isotopic composition of seawater is associated with manganese oxide burial because large variability in low temperature ocean crust alteration is controlled by long-term, multi-million years, average ocean crust production rates. This study presents new Tl isotope data for an open ocean transect in the South Atlantic, and depth transects for two euxinic basins (anoxic and free sulfide in the water column), the Cariaco Basin and Black Sea. The Tl isotopic signature of open ocean seawater in the South Atlantic was found to be homogeneous with ε205Tl = -6.0 ± 0.3 (±2 SD, n = 41) while oxic waters from Cariaco and the Black Sea are -5.6 and -2.2, respectively. Combined with existing data from the Pacific and Arctic Oceans, our Atlantic data establish the conservatism of Tl isotopes in the global ocean. In contrast, partially- and predominantly-restricted basins reveal Tl isotope differences that vary between open-ocean (-6) and continental material (-2) ε205Tl, scaling with the degree of restriction. Regardless of the differences between basins, Tl is quantitatively removed from their euxinic waters below the chemocline. The burial of Tl in euxinic sediments is estimated to be an order of magnitude

  4. In vivo effects of radioactive properties of Tl-201 on human carbonic anhydrase activity

    Science.gov (United States)

    Sahin, Ali; Senturk, Murat

    2017-04-01

    Carbonic anhydrase (CA) is a family of metalloenzymes that requires Zn as a cofactor and catalyze the quick conversion of CO2 to HCO3- and H+. Inhibitors of the carbonic anhydrases (CAs) have medical usage of significant diseases such as glaucoma, epilepsy, gastroduodenal ulcers, acid-base disequilibria and neurological disorders. The most useful radioisotope, Tl-201, decays by electron capture, emitting Hg X-rays ( 70-80 keV), and photons of 135 and 167 keV in 10% total abundance. Therefore, it has good imaging characteristics without excessive patient radiation dose. It is the most popular isotope used for thallium 201 nuclear cardiac stress tests. In the present study, In vivo inhibitory effect of Tl-201 (Thallium-201) on human erythrocyte carbonic anhydrase (CA) activity were investigated.

  5. Thallium isotopes as a potential tracer for the origin of cratonic eclogites

    Science.gov (United States)

    Nielsen, Sune G.; Williams, Helen M.; Griffin, William L.; O'Reilly, Suzanne Y.; Pearson, Norman; Viljoen, Fanus

    2009-12-01

    Cratonic eclogites are inferred to originate either from subducted ocean crust or mantle melts accreted onto the roots of continents. These models have different implications for the growth of continents, but it is currently difficult to determine the origin of individual eclogite suites. Upper ocean crust altered at low temperatures and marine sediments both display high thallium (Tl) concentrations and strongly fractionated Tl isotope signatures relative to the ambient upper mantle. In this study we carry out the first examination of the suitability of Tl isotopes as a tracer for an ocean-crust origin of cratonic eclogites. We have analysed the Tl isotope composition of clinopyroxene and garnet in six eclogites from the Kaalvallei and Bellsbank kimberlite pipes in South Africa. Minerals were pre-cleaned with an HCl leaching technique and the leachates display variably light Tl isotope ratios. These most likely reflect low-temperature hydrothermal alteration occurring after eruption of the kimberlite that carried the eclogites to the surface. The leached mineral pairs all display identical Tl isotope ratios, strongly suggesting that the source of the analysed Tl is identical for each mineral pair. It is, however, not possible to exclude the possibility that the analysed Tl originates from kimberlitic material that was not removed by the cleaning procedure. Only one of the six samples exhibits a Tl isotope composition different from ambient mantle. Assuming that the Tl isotope signatures indeed represent the eclogite minerals and not any form of contamination, the Tl isotope composition in this sample is consistent with containing a minor component (low temperatures. Thallium isotopes may become one of the most sensitive indicators for the presence of low-T altered ocean crust because of the stark contrast in Tl concentration and isotopic composition between the mantle and altered ocean crust. In fact, no other chemical or isotopic tracer could have provided an

  6. Thallium-201 SPECT in the diagnosis of head and neck cancer.

    Science.gov (United States)

    Valdés Olmos, R A; Balm, A J; Hilgers, F J; Koops, W; Loftus, B M; Tan, I B; Muller, S H; Hoefnagel, C A; Gregor, R T

    1997-06-01

    The accuracy of SPECT with 201Tl-chloride for the diagnosis of primary tumors, lymph node metastases and recurrences in head and neck cancer was evaluated for clinical applicability. SPECT images, obtained 60 min after administration of 150 MBq 201Tl-chloride, were compared with clinical, CT and/or MRI and histology results. In addition, whole-body images were obtained to detect distant metastases. In 79 patients studied for primary tumors (principally larynix, hypopharynx, oropharynx, nasopharynx and oral cavity), 201Tl SPECT correctly identified 69 of 73 (95% versus 88% for CT/MRI) histologically confirmed malignancies including 63 squamous-cell carcinomas. The method localized four occult naso- and oropharynx carcinomas not seen on CT/MRI and was correctly negative in two patients without tumor and in three of four patients with no confirmed primary tumor in the head and neck. With respect to regional spread, only patients who had cervical lymph node dissection were evaluated, and the findings were recorded per side of the neck. Thallium-201 SPECT correctly identified metastases in 31 of 36 neck dissections with proven lymph node involvement (86%), was correctly negative in nine and false-positive in one. Although the sensitivity of CT/MRI was clearly higher (97%), considerably more false-positive cases affected its accuracy (81% versus 87% for SPECT). In 30 patients investigated for recurrences, 201Tl SPECT correctly identified 27 of 29 microscopically confirmed tumor sites (93%) and was correctly negative in seven. Sensitivity of CT/MRI was lower (76%), and a greater number of false-positives (seven versus three for SPECT) further decreased its accuracy (64% versus 87% for SPECT). Distant metastases were detected in five patients. Thallium-201 SPECT appears to be an accurate method for the diagnosis of head and neck cancer. The method is particularly useful for detection of occult head and neck tumors and for assessing recurrences. It also may be of

  7. Thallium in spawn, juveniles, and adult common toads (Bufo bufo) living in the vicinity of a zinc-mining complex, Poland.

    Science.gov (United States)

    Dmowski, Krzysztof; Rossa, Monika; Kowalska, Joanna; Krasnodębska-Ostręga, Beata

    2015-01-01

    A breeding population of the common toad Bufo bufo living in the vicinity of a Zn-Pb smelting works in Bukowno, Poland was studied for the presence of thallium. Tl concentration was measured in the bottom sediments of the spawning pond, in the laid eggs, in juveniles after metamorphosis, and in the selected tissues of the adult individuals. A very high concentration of Tl was detected in the spawn (13.97 ± 8.90 mg/kg d.w.). In 50% of the spawn samples, levels exceeded 20 mgTl/kg d.w. The issue of maternal transfer of thallium from females to oocytes is discussed. Due to a significant accumulation of thallium, spawn analysis can be used as a sensitive indicator of the presence of this element in the environment and may replace more invasive methods that involve the killing of adult animals. In those regions that are abundant in Zn-Pb ores, the spawn of amphibians may be a very important source of thallium contamination for predators. From among all tissues of the Bukowno adult toads, the livers have shown the highest accumulation of thallium (mean 3.98 mg/kg d.w. and maximum value--18.63). For as many as 96.5% of livers, concentrations exceeded 1.0 mgTl/kg d.w. which is treated as indicative of poisoning.

  8. In-situ pre-concentration through repeated sampling and pyrolysis for ultrasensitive determination of thallium in drinking water by electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Liu, Liwei; Zheng, Huaili; Xu, Bincheng; Xiao, Lang; Chigan, Yong; Zhangluo, Yilan

    2018-03-01

    In this paper, a procedure for in-situ pre-concentration in graphite furnace by repeated sampling and pyrolysis is proposed for the determination of ultra-trace thallium in drinking water by graphite furnace atomic absorption spectrometry (GF-AAS). Without any other laborious enrichment processes that routinely result in analyte loss and contamination, thallium was directly concentrated in the graphite furnace automatically and subsequently subject to analysis. The effects of several key factors, such as the temperature for pyrolysis and atomization, the chemical modifier, and the repeated sampling times were investigated. Under the optimized conditions, a limit of detection of 0.01µgL -1 was obtained, which fulfilled thallium determination in drinking water by GB 5749-2006 regulated by China. Successful analysis of thallium in certified water samples and drinking water samples was demonstrated, with analytical results in good agreement with the certified values and those by inductively coupled plasma mass spectrometry (ICP-MS), respectively. Routine spike-recovery tests with randomly selected drinking water samples showed satisfactory results of 80-96%. The proposed method is simple and sensitive for screening of ultra-trace thallium in drinking water samples. Copyright © 2017. Published by Elsevier B.V.

  9. The ECG component of Thallium-201 exercise testing impacts on cardiac intervention rates

    Energy Technology Data Exchange (ETDEWEB)

    Deague, J.; Salehi, N.; Grigg, L.; Lichtenstein, M.; Better, N. [Royal Melbourne Hospital, Parkville, VIC (Australia). Departments of Nuclear Medicine and Cardiology

    1998-06-01

    Full text: Thallium exercise testing (Tlex) offers superior sensitivity and specificity to exercise electrocardiography (ECG), but the value of the ECG data in Tlex remains poorly studied. While a normal Tlex is associated with an excellent prognosis, patients with a positive Tlex have a higher cardiac event rate. We aimed to see if a negative ECG Component of the Tlex (ECGTl) was associated with an improved outcome compared with a positive ECGTl, in those patients with a reversible Tlex defect. We followed 100 consecutive patients retrospectively with a reversible defect on Tlex (50 with negative and 50 with positive ECGTI) for 12 months. The ECG was reviewed as positive (1mm ST depression 0.08 seconds after J point or >2mm if on digoxin or prior ECG changes), negative, equivocal or uninterpretable. We excluded patients with pharmacological testing, and those with equivocal or uninterpretable ECGs. End-points included angiography, cardiac interventions and cardiac event rate (CER) incorporating unstable angina, acute myocardial infarction, and cardiac death. In conclusion 24% of patients with reversible defects on Tlex who had a negative ECGTI still proceeded to PTCA or CABG. Those with a positive ECGTI had a higher incidence of angiography and cardiac revascularisation, but this difference was only evident in patients with mild to moderate reversibility

  10. EFFECTS OF THALLIUM ON THE LARVAL DEVELOPMENT OF LUCILIA SERICATA MEIGEN 1826 AND PMI ESTIMATION

    Directory of Open Access Journals (Sweden)

    Arif Gökhan BAŞARAN

    2011-08-01

    Full Text Available Determination of larval growth rate of and forensic analysis of the age of Calliphoridae larvae on a corpse are useful evidence in legal investigations for the estimation of exact death time and time duration after death; post mortem interval. However many factors, such as temperature, tissue type and contamination of drugs and toxins, effect larval development of blow fly larvae and consequently theestimation of post mortem interval. The present study examined the larval growth rate of a forensically important blow fly species, Lucilia sericata Meigen 1826 in different concentrations (0,12; 0,25; 0,50; 1 and 2 μg/g of toxic heavy metal Thallium under controlled laboratory conditions. Body length and weight, death ratio of larvae and pupa between experimental and control groups were compared. Results demonstrated that the development rate of larvae between uncontaminated and contaminated diets varies significantly. In short, they molted later, reached maximum length more slowly and sometimesproduced significantly smaller pupae in contaminated food source. These results emphasized that the importance of determining the contamination rate of toxins in tissue for the forensic entomologist,while using development rates from standard curves based on larvae fed non-contaminated mediums.

  11. Value of transient dilation of the left ventricular cavity on stress thallium scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Sugihara, Hiroki; Shiga, Kouji; Umamoto, Ikuo (Kyoto Prefectural Univ. of Medicine (Japan)) (and others)

    1991-02-01

    This study was undertaken to evaluate the value of transient dilation of the left ventricular cavity on stress thallium scintigraphy in 80 patients with ischemic heart disease (IHD) and 50 with hypertrophic cardiomyopathy (HCM). Twenty persons without either coronary artery stenosis or heart disease were served as controls. Areas surrounded by maximum count points on the line of each 10deg on the short axis slice through the mid-cavity of the left ventricle were obtained at 10 minutes and at 3 hours after exercise. Transient dilation index (TDI) was obtained by dividing the area on early image by that on delayed image. TDI was significantly higher in patients with two or three vessel disease in the IHD group than the control group. High TDI was observed in 8% for one vessel disease, 40% for two vessel disease, and 80% for three vessel disease, contributing to the detection of multivessel IHD. In the HCM group of 80 patients, 24 (48%) had high TDI which was frequently associated with a history of chest pain and positive ECG findings at exercise. When these 24 HCM patients underwent exercise blood pool scintiscanning, left ventricular enddiastolic volume was similar before and at 10 minutes after exercise. These findings suggest that transient dilation of the left ventricular cavity after exercise may reflect subendocardial ischemia in both IHD and HCM. TDI would become a useful indicator for transient dilation of the left ventricular cavity. (N.K.).

  12. Clinicopathologic correlation study of thallium-201 myocardial scintigraphy in diagnosis of myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Chida, Kouji; Sugiura, Masaya; Ohkawa, Shin-ichiro

    1987-05-01

    In a series of 1,000 consecutive autopsy cases, we evaluated the clinical utility of thallium-201 (Tl-201) myocardial scintigraphy and electrocardiography (ECG) in 101 patients who had been studied while alive. Fifty-five cases had myocardial infarctions (MI) at autopsy. The Tl-201 scintigram and ECG in diagnosis of MI showed sensitivities of 68 % and 60 %, specificities of 87 % and 83 %, and diagnostic accuracies of 76 % and 70 %, respectively. The sensitivity of the Tl-201 scintigram was 70 % in anterior MI, 80 % in postero-inferior MI, 25 % in lateral and subendocardial infarction. The sensitivity was 88 % for large massive MI, but was low in scattered (50 %) or middle-sized MI (17 %). The diagnostic limit of the resolution of Tl-201 scintigrams was 4.5 cm in long diameter. All 8 cases with MI of less than 4 cm could not be diagnosed with the technique. There were 48 cases of large MI (more than 5 cm), but 8 cases could not be diagnosed by scintigraphy because of non-transmural or scattered MI. A comparison of the Tl-201 scintigram and ECG showed that 27 cases out of 60 cases were diagnosed by both methods, 14 only by the Tl-201 scintigram, 9 only by ECG and 10 by neither method.

  13. Evaluation of myocardial damage in Duchenne's muscular dystrophy with thallium-201 myocardial SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Tamura, Takuhisa; Shibuya, Noritoshi (Kawatana National Hospital, Nagasaki (Japan)); Hashiba, Kunitake; Oku, Yasuhiko; Mori, Hideki; Yano, Katsusuke

    1993-01-01

    Myocardial damage and cardiopulmonary functions in patients with Duchenne's muscular dystrophy (DMD) were assessed using thallium-201 myocardial single-photon emission computed tomography (SPECT) and technetium-99m multigated radionuclide angiography. Twenty-five patients with DMD were divided into 4 groups according to percent of perfusion defect (%PD) calculated by the bull's-eye method and age. PD was detected in 24 (96.0%) of 25 patients with DMD, and it spread from the left ventricular lateral wall to the anterior wall and/or interventricular septum. PD was detected even in a 6-year-old DMD boy. Patients in Group I (%PD[>=]10% and age<15 years old) were shown to have a higher risk of left-sided heart failure without respiratory failure. Patients in Group II (%PD[>=]10 and age[>=]15) showed decreased pulmonary function and worsened arterial blood gas values as compared with Group IV (%PD<10 and age[>=]15). There was no significant difference in cardiac function among the 4 groups. It is postulated that myocardial damage in Group II patients is dependent primarily on a deficiency of dystrophin and on chronic respiratory failure, and that some of them are at risk of cardiopulmonary failure. It is concluded that myocardial SPECT is useful for the early diagnosis of myocardial damage and evaluation of cardiopulmonary function in DMD patients. (author).

  14. Role of relativity in high-pressure phase transitions of thallium.

    Science.gov (United States)

    Kotmool, Komsilp; Chakraborty, Sudip; Bovornratanaraks, Thiti; Ahuja, Rajeev

    2017-02-20

    We demonstrate the relativistic effects in high-pressure phase transitions of heavy element thallium. The known first phase transition from h.c.p. to f.c.c. is initially investigated by various relativistic levels and exchange-correlation functionals as implemented in FPLO method, as well as scalar relativistic scheme within PAW formalism. The electronic structure calculations are interpreted from the perspective of energetic stability and electronic density of states. The full relativistic scheme (FR) within L(S)DA performs to be the scheme that resembles mostly with experimental results with a transition pressure of 3 GPa. The s-p hybridization and the valence-core overlapping of 6s and 5d states are the primary reasons behind the f.c.c. phase occurrence. A recent proposed phase, i.e., a body-centered tetragonal (b.c.t.) phase, is confirmed with a small distortion from the f.c.c. phase. We have also predicted a reversible b.c.t. → f.c.c. phase transition at 800 GPa. This finding has been suggested that almost all the III-A elements (Ga, In and Tl) exhibit the b.c.t. → f.c.c. phase transition at extremely high pressure.

  15. High thallium concentrations in soils from sites of historical Ag, Pb, and Zn mining in western Małopolska (S Poland

    Directory of Open Access Journals (Sweden)

    Woch M. W.

    2013-04-01

    Full Text Available The aim of this study was to assess thallium concentration in topsoil originating from sites of historical mining of Ag, Pb and Zn in western Małopolska (S Poland. Soil samples were collected from 63 sites, sieved, ground and digested in hot HClO4. Thallium concentration was measured with an atomic absorption spectrometer. Thallium concentrations averaged 20.84 mg kg-1 and varied from 4.42 to 49.82 mg kg-1. In all studied soils they exceeded values typical for uncontaminated soils (0.02 to 2.8 mg Tl kg-1. This indicates that Tl contamination may threaten the environment and public health. Routine monitoring of Tl contamination in southern Poland is required.

  16. Preconcentration of thallium(III) with 2,6-bis( N-phenyl carbamoyl) pyridine on microcrystalline naphthalene prior to its trace determination in human serum spectrophotometrically

    Science.gov (United States)

    Rezaei, B.; Meghdadi, S.; Majidi, N.

    2007-05-01

    A novel, simple, sensitive and effective method has been developed for preconcentration of thallium on 2,6-bis( N-phenyl carbamoyl)pyridine-naphthalene adsorbent in the pH range 5.0-10.0, prior to its spectrophotometric determination, based on the oxidation of bromopyrogallol red at λ = 518 nm. This method makes it possible to quantitize thallium in the range of 3.0 × 10 -9 to 1.0 × 10 -5 M, with a detection limit (S/N = 3) of 1.2 × 10 -9 M. This procedure has been successfully applied to determine the ultra trace levels of thallium in the environmental and biological samples, free from the interference of some diverse ions. The precision, expressed as relative standard deviation of three measurements is better than 4.17%.

  17. Biphasic thallium 201 SPECT-imaging for the noninvasive diagnosis of myocardial perfusion abnormalities in a child with Kawasaki disease--a case report

    Energy Technology Data Exchange (ETDEWEB)

    Hausdorf, G.; Nienaber, C.A.; Spielman, R.P.

    1988-02-01

    The mucocutaneous lymph node syndrome (Kawasaki disease) is of increasing importance for the pediatric cardiologist, for coronary aneurysms with the potential of thrombosis and subsequent stenosis can develop in the course of the disease. The authors report a 2 1/2-year-old female child in whom, fourteen months after the acute phase of Kawasaki disease, myocardial infarction occurred. Biphasic thallium 201 SPECT-imaging using dipyridamole depicted anterior wall ischemia and inferolateral infarction. This case demonstrates that noninvasive vasodilation-redistribution thallium 201 SPECT-imaging has the potential to predict reversible myocardial perfusion defects and myocardial necrosis, even in small infants with Kawasaki disease.

  18. Influence of the Dirac-Hartree-Fock starting potential on the parity-nonconserving electric-dipole-transition amplitudes in cesium and thallium

    Science.gov (United States)

    Perger, W. F.; Das, B. P.

    1987-01-01

    The parity-nonconserving electric-dipole-transition amplitudes for the 6s1/2-7s1/2 transition in cesium and the 6p1/2-7p1/2 transition in thallium have been calculated by the Dirac-Hartree-Fock method. The effects of using different Dirac-Hartree-Fock atomic core potentials are examined and the transition amplitudes for both the length and velocity gauges are given. It is found that the parity-nonconserving transition amplitudes exhibit a greater dependence on the starting potential for thallium than for cesium.

  19. Assessment of myocardial viability by dynamic tomographic iodine 123 iodophenylpentadecanoic acid imaging: comparison with rest-redistribution thallium 201 imaging.

    Science.gov (United States)

    Iskandrian, A S; Powers, J; Cave, V; Wasserleben, V; Cassell, D; Heo, J

    1995-01-01

    This study examined the ability of dynamic 123I-labeled iodophenylpentadecanoic acid (IPPA) imaging to detect myocardial viability in patients with left ventricular (LV) dysfunction caused by coronary artery disease. Serial 180-degree single-photon emission computed tomographic (SPECT) images (five sets, 8 minutes each) were obtained starting 4 minutes after injection of 2 to 6 mCi 123I at rest in 21 patients with LV dysfunction (ejection fraction [EF] 34% +/- 11%). The segmental uptake was compared with that of rest-redistribution 201Tl images (20 segments/study). The number of perfusion defects (reversible and fixed) was similar by IPPA and thallium (11 +/- 5 vs 10 +/- 5 segments/patient; difference not significant). There was agreement between IPPA and thallium for presence or absence (kappa = 0.78 +/- 0.03) and nature (reversible, mild fixed, or severe fixed) of perfusion defects (kappa = 0.54 +/- 0.04). However, there were more reversible IPPA defects than reversible thallium defects (7 +/- 4 vs 3 +/- 4 segments/patient; p = 0.001). In 14 patients the EF (by gated pool imaging) improved after coronary revascularization from 33% +/- 11% to 39% +/- 12% (p = 0.002). The number of reversible IPPA defects was greater in the seven patients who had improvement in EF than in the patients without such improvement (10 +/- 4 vs 5 +/- 4 segments/patient; p = 0.075). 123I-labeled IPPA SPECT imaging is a promising new technique for assessment of viability. Reversible defects predict recovery of LV dysfunction after coronary revascularization.

  20. Self-propagating high-temperature synthesis (SHS) and microwave-assisted combustion synthesis (MACS) of the thallium superconducting phases

    Science.gov (United States)

    Bayya, S. S.; Snyder, R. L.

    1994-05-01

    This paper explores the speed of reaction as a parameter to minimizing thallium loss. Self-propagating high-temperature synthesis (SHS) and microwave-assisted combustion synthesis (MACS) were developed for the synthesis of Tl-2212 and Tl-2223 superconductors using Cu metal powder as a fuel. A kitchen microwave oven was used to carry out MACS reactions. The samples were reacted for few seconds and led to the formation of the superconducting phases. Further explorations and modifications in the processing could lead to the formation of single phases by MACS.

  1. Tracking along-arc sediment inputs to the Aleutian arc using thallium isotopes

    Science.gov (United States)

    Nielsen, Sune G.; Yogodzinski, Gene; Prytulak, Julie; Plank, Terry; Kay, Suzanne M.; Kay, Robert W.; Blusztajn, Jerzy; Owens, Jeremy D.; Auro, Maureen; Kading, Tristan

    2016-05-01

    Sediment transport from the subducted slab to the mantle wedge is an important process in understanding the chemical and physical conditions of arc magma generation. The Aleutian arc offers an excellent opportunity to study sediment transport processes because the subducted sediment flux varies systematically along strike (Kelemen et al., 2003) and many lavas exhibit unambiguous signatures of sediment addition to the sub-arc mantle (Morris et al., 1990). However, the exact sediment contribution to Aleutian lavas and how these sediments are transported from the slab to the surface are still debated. Thallium (Tl) isotope ratios have great potential to distinguish sediment fluxes in subduction zones because pelagic sediments and low-temperature altered oceanic crust are highly enriched in Tl and display heavy and light Tl isotope compositions, respectively, compared with the upper mantle and continental crust. Here, we investigate the Tl isotope composition of lavas covering almost the entire Aleutian arc a well as sediments outboard of both the eastern (DSDP Sites 178 and 183) and central (ODP Hole 886C) portions of the arc. Sediment Tl isotope compositions change systematically from lighter in the Eastern to heavier in the Central Aleutians reflecting a larger proportion of pelagic sediments when distal from the North American continent. Lavas in the Eastern and Central Aleutians mirror this systematic change to heavier Tl isotope compositions to the west, which shows that the subducted sediment composition is directly translated to the arc east of Kanaga Island. Moreover, quantitative mixing models of Tl and Pb, Sr and Nd isotopes reveal that bulk sediment transfer of ∼0.6-1.0% by weight in the Eastern Aleutians and ∼0.2-0.6% by weight in the Central Aleutians can account for all four isotope systems. Bulk mixing models, however, require that fractionation of trace element ratios like Ce/Pb, Cs/Tl, and Sr/Nd in the Central and Eastern Aleutians occurs after

  2. Controls on thallium uptake during hydrothermal alteration of the upper ocean crust

    Science.gov (United States)

    Coggon, Rosalind M.; Rehkämper, Mark; Atteck, Charlotte; Teagle, Damon A. H.; Alt, Jeffrey C.; Cooper, Matthew J.

    2014-11-01

    Hydrothermal circulation is a fundamental component of global biogeochemical cycles. However, the magnitude of the high temperature axial hydrothermal fluid flux remains disputed, and the lower temperature ridge flank fluid flux is difficult to quantify. Thallium (Tl) isotopes behave differently in axial compared to ridge flank systems, with Tl near-quantitatively stripped from the intrusive crust by high temperature hydrothermal reactions, but added to the lavas during low temperature reaction with seawater. This contrasting behavior provides a unique approach to determine the fluid fluxes associated with axial and ridge flank environments. Unfortunately, our understanding of the Tl isotopic mass balance is hindered by poor knowledge of the mineralogical, physical and chemical controls on Tl-uptake by the ocean crust. Here we use analyses of basaltic volcanic upper crust from Integrated Ocean Drilling Program Hole U1301B on the Juan de Fuca Ridge flank, combined with published analyses of dredged seafloor basalts and upper crustal basalts from Holes 504B and 896A, to investigate the controls on Tl-uptake by mid-ocean ridge basalts and evaluate when in the evolution of the ridge flank hydrothermal system Tl-uptake occurs. Seafloor basalts indicate an association between basaltic uptake of Tl from cold seawater and uptake of Cs and Rb, which are known to partition into K-rich phases. Although there is no clear relationship between Tl and K contents of seafloor basalts, the data do not rule out the incorporation of at least some Tl into the same minerals as the alkali elements. In contrast, we find no relationship between the Tl content and either the abundance of secondary phyllosilicate minerals, or the K, Cs or Rb contents in upper crustal basalts. We conclude that the uptake of Tl and alkali elements during hydrothermal alteration of the upper crust involves different processes and/or mineral phases compared to those that govern seafloor weathering. Furthermore

  3. Chemistry and phase evolution during roasting of toxic thallium-bearing pyrite.

    Science.gov (United States)

    Lopez-Arce, Paula; Garcia-Guinea, Javier; Garrido, Fernando

    2017-08-01

    In the frame of a research project on microscopic distribution and speciation of geogenic thallium (Tl) from contaminated mine soils, Tl-bearing pyrite ore samples from Riotinto mining district (Huelva, SW Spain) were experimentally fired to simulate a roasting process. Concentration and volatility behavior of Tl and other toxic heavy metals was determined by quantitative ICP-MS, whereas semi-quantitative mineral phase transitions were identified by in situ thermo X-Ray Diffraction (HT-XRD) and Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) analyses after each firing temperature. Sample with initial highest amount of quartz (higher Si content), lowest quantity of pyrite and traces of jarosite (lower S content) developed hematite and concentrated Tl (from 10 up to 72 mg kg-1) after roasting at 900 °C in an oxidizing atmosphere. However, samples with lower or absent quartz content and higher pyrite amount mainly developed magnetite, accumulating Tl between 400 and 500 °C and releasing Tl from 700 up to 900 °C (from 10-29 mg kg-1 down to 4-1 mg kg-1). These results show the varied accumulative, or volatile, behaviors of one of the most toxic elements for life and environment, in which oxidation of Tl-bearing Fe sulfides produce Fe oxides wastes with or without Tl. The initial chemistry and mineralogy of pyrite ores should be taken into account in coal-fired power stations, cement or sulfuric acid production industry involving pyrite roasting processes, and steel, brick or paint industries, which use iron ore from roasted pyrite ash, where large amounts of Tl entail significant environmental pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Measurement of the parity nonconserving neutral weak interaction in atomic thallium

    Energy Technology Data Exchange (ETDEWEB)

    Bucksbaum, P.H.

    1980-11-01

    This thesis describes an experiment to measure parity nonconservation in atomic thallium. A frequency doubled, flashlamp pumped tunable dye laser is used to excite the 6P/sub 1/2/(F = 0) ..-->.. 7P/sub 1/2/(F = 1) transition at 292.7 nm, with circularly polarized light. An electrostatic field E of 100 to 300 V/cm causes this transition to occur via Stark induced electric dipole. Two field free transitions may also occur: a highly forbidden magnetic dipole M, and a parity nonconserving electric dipole epsilon/sub P/. The latter is presumed to be due to the presence of a weak neutral current interaction between the 6p valence electron and the nucleus, as predicted by gauge theories which unite the electromagnetic and weak interactions. Both M and epsilon/sub P/ interfere with the Stark amplitude ..beta..E to produce a polarization of the 7P/sub 1/2/ state. This is measured with a circularly polarized infrared laser beam probe, tuned to the 7P/sub 1/2/ ..-->.. 8S/sub 1/2/ transition. This selectively excites m/sub F/ = +1 or -1 components of the 7P/sub 1/2/ state, and the polarization is seen as an asymmetry in 8S ..-->.. 6P/sub 3/2/ fluorescence when the probe helicity is reversed. The polarization due to M is ..delta../sub M/ = -2M/(BETAE). It is used to calibrate the analyzing efficiency. The polarization due to epsilon/sub P/ is ..delta../sub P/ = 2i epsilon/sub P//(..beta..E), and can be distinguished from ..delta../sub M/ by its properties under reversal of the 292.7 nm photon helicity and reversal of the laser direction. A preliminary measurement yielded a parity violation in agreement with the gauge theory of Weinberg and Salam.

  5. MRI and thallium-201 SPECT in the prediction of survival in glioma

    Energy Technology Data Exchange (ETDEWEB)

    Vos, Maaike J. [VU University Medical Center, Department of Neurology, Amsterdam (Netherlands); Medical Center Haaglanden, Department of Neurology, PO Box 432, The Hague (Netherlands); Berkhof, Johannes [VU University Medical Center, Department of Epidemiology and Biostatistics, Amsterdam (Netherlands); Hoekstra, Otto S. [VU University Medical Center, Department of Nuclear Medicine and PET Research, Amsterdam (Netherlands); Bosma, Ingeborg; Sizoo, Eefje M.; Heimans, Jan J.; Reijneveld, Jaap C.; Postma, Tjeerd J. [VU University Medical Center, Department of Neurology, Amsterdam (Netherlands); Sanchez, Esther [VU University Medical Center, Department of Radiology, Amsterdam (Netherlands); Lagerwaard, Frank J. [VU University Medical Center, Department of Radiation Oncology, Amsterdam (Netherlands); Buter, Jan [VU University Medical Center, Department of Medical Oncology, Amsterdam (Netherlands); Noske, David P. [VU University Medical Center, Department of Neurosurgery and Neuro-Oncology Research Group, Amsterdam (Netherlands)

    2012-06-15

    This paper aims to study the value of MRI and Thallium 201 ({sup 201}Tl) single-photon emission computed tomography (SPECT) in the prediction of overall survival (OS) in glioma patients treated with temozolomide (TMZ) and to evaluate timing of radiological follow-up. We included patients treated with TMZ chemoradiotherapy for newly diagnosed glioblastoma multiforme (GBM) and with TMZ for recurrent glioma. MRIs and {sup 201}Tl SPECTs were obtained at regular intervals. The value of both imaging modalities in predicting OS was examined using Cox regression analyses. Altogether, 138 MRIs and 113 {sup 201}Tl SPECTs in 46 patients were performed. Both imaging modalities were strongly related to OS (P {<=} 0.02). In newly diagnosed GBM patients, the last follow-up MRI (i.e., after six adjuvant TMZ courses) and SPECT (i.e., after three adjuvant TMZ courses) were the strongest predictors of OS (P = 0.01). In recurrent glioma patients, baseline measurements appeared to be the most predictive of OS (P < 0.01). The addition of one imaging modality to the other did not contribute to the prediction of OS. Both MRI and {sup 201}Tl SPECT are valuable in the prediction of OS. It is adequate to restrict to one of both modalities in the radiological follow-up during treatment. In the primary GBM setting, MRI after six adjuvant TMZ courses contributes significantly to the prediction of survival. In the recurrent glioma setting, baseline MRI appears to be a powerful predictor of survival, whereas follow-up MRIs during TMZ seem to be of little additional value. (orig.)

  6. Synthesis, calorimetric, structural and conductivity studies in a new thallium selenate tellurate adduct compound

    Energy Technology Data Exchange (ETDEWEB)

    Ktari, L. [Laboratoire de l' Etat Solide (LES), Faculte des Sciences de Sfax, 3000 Sfax (Tunisia); Abdelhedi, M. [Laboratoire de l' Etat Solide (LES), Faculte des Sciences de Sfax, 3000 Sfax (Tunisia); Laboratoire Leon Brouillon LLB, CEA Saclay, 91191 Gif-Sur-Yvette Cedex (France); Bouhlel, N. [Laboratoire de l' Etat Solide (LES), Faculte des Sciences de Sfax, 3000 Sfax (Tunisia); Dammak, M., E-mail: meddammak@yahoo.fr [Laboratoire de l' Etat Solide (LES), Faculte des Sciences de Sfax, 3000 Sfax (Tunisia); Cousson, A. [Laboratoire Leon Brouillon LLB, CEA Saclay, 91191 Gif-Sur-Yvette Cedex (France)

    2009-08-05

    The crystal structure of the thallium selenate tellurate Tl{sub 2}SeO{sub 4}.Te(OH){sub 6} (TlSeTe) was determined by X-ray diffraction method. The title compound crystallizes in the monoclinic system with P2{sub 1}/c space group. The following parameters are: a = 12.358(3) A; b = 7.231(1) A; c = 11.986(2) A; {beta} = 111.092(2){sup o}; Z = 4. The structure can be regarded as being built of isolated TeO{sub 6} octahedra and SeO{sub 4} tetrahedra. The Tl{sup +} cations are intercalated between these kinds of polyhedra. The main feature of this structure is the coexistence of two different and independent anions (SeO{sub 4}{sup 2-} and TeO{sub 6}{sup 6-}) in the same unit cell. The structure is stable due to O-H...O hydrogen bonds which link tetrahedral and octahedral groups. Crystals of Tl{sub 2}SeO{sub 4}.Te(OH){sub 6} undergo three endothermal transitions at 373, 395 and 437 K. These transitions are detected by DSC and analyzed by dielectric measurements with impedance spectroscopy. The evolution of conductivity versus temperature showed the presence of a protonic conduction phase transition at 437 K. The phase transition at 373 K can be related to a structural phase transition, whereas the one at 395 K is ascribed as likely due to a ferroelectric-paraelectric phase transition.

  7. Electrochemical properties of modified copper-thallium hexacyanoferrate electrode in the presence of different univalent cations

    Energy Technology Data Exchange (ETDEWEB)

    Rutkowska, Iwona A.; Stroka, Jadwiga [Department of Chemistry, University of Warsaw, Pasteura 1, PL-02-093 Warsaw (Poland); Galus, Zbigniew [Department of Chemistry, University of Warsaw, Pasteura 1, PL-02-093 Warsaw (Poland)], E-mail: zbgalus@chem.uw.edu.pl

    2008-04-20

    The preparation of copper(II) hexacyanoferrate (CuHCF) films on the surface of gold electrodes as well as their characterization in solutions of various alkali metal and NH{sub 4}{sup +} cations and in the presence of thallium(I) are described. The electrochemical quartz crystal microbalance and cyclic voltammetric techniques were used. In 0.50 M lithium nitrate, even at submillimolar concentration of Tl(I), the formal potential of CuHCF was shifted to more positive values. At higher Tl(I) concentrations, the formal potential of the CuHCF redox reaction changed linearly with the logarithm of Tl(I) concentration (in the 0.50 M solution of lithium or another alkali metal nitrate). From such dependencies, selectivity coefficients K{sub Tl/M} were calculated, and they show that the CuHCF film on the gold electrode interacts preferentially with Tl(I). High affinity of Tl(I) to copper hexacyanoferrate, that was observed in the presence of alkali metal cations, was explained by relatively strong donor-acceptor interactions of Tl(I) ions with nitrogen in CN groups of the CuHCF film. It was also shown for simple M{sub 4}[Fe(CN){sub 6}] metal ferrocyanate salts (where M = Li{sup +}, Na{sup +}, K{sup +}, Rb{sup +}, Cs{sup +} and Tl{sup +}) that there is a preferential interaction of Tl{sup +} with CN group consistent with formation of a Tl-NC-Fe bridge.

  8. Quantitative evaluation of thallium-201 myocardial scintigram in coronary artery diseases

    Energy Technology Data Exchange (ETDEWEB)

    Mikada, Ken-etsu (Akita Univ. (Japan). School of Medicine)

    1992-11-01

    Quantitative indices from circumferential profile curves of thallium-201 ([sup 201]Tl) myocardial scintigram were evaluated for diagnostic utility in coronary artery diseases (CAD). Myocardial [sup 201]Tl scintigrams with single photon emission computed tomography (SPECT) were obtained 5 minutes (early) and 4 hours (delayed) after exercise in 20 normal subjects and 66 cases of CAD, of which 20 were angina pectoris without myocardial infarction (AP), 14 were subendocardial infarction (non-QMI) and 32 were Q-wave infarction (QMI). Tl counts, %Tl uptake and washout ratio (WR) were measured in 81 segments (9 apical segments of the slice from the longitudinal axis and all 72 segments of two slices from the short axis). A mean early defect (MED), a mean delayed defect (MDD), a mean delta washout rate (MDR), and a [Sigma] delayed defect ([Sigma]DD) were calculated from the areas which were below the two standard deviations of the mean %Tl uptake in normal subjects. A mean filling-in (MFI) was calculated from the difference of the %Tl uptake between early and delayed curves in each patient. In patients with CAD, the MED and MFI were higher, but MDW was lower with a more severe coronary stenosis, indicating that these indices were useful to detect myocardial hypo-perfuion. In severely stenotic regions, the MDD was higher in QMI than in AP and non-QMI, indicating that the ratio of infarct to the myocardium in the region was higher in QMI. In QMI, [Sigma]DD correlated well (r=0.723) with Total Wall Motion Scores with two-dimentional echocardiography which was directly related with infarct size. Further, MED, MFI and MDW were improved after aortocoronary bypass only in patients with patent graft. It is concluded that this quantitative evaluation with [sup 201]Tl-SPECT can provide an objective and quantitative estimate of regional myocardial ischemia and infarct. (author).

  9. Thallium-201 for cardiac stress tests: residual radioactivity worries patients and security.

    Science.gov (United States)

    Geraci, Matthew J; Brown, Norman; Murray, David

    2012-12-01

    A 47-year-old man presented to the Emergency Department (ED) in duress and stated he was "highly radioactive." There were no reports of nuclear disasters, spills, or mishaps in the local area. This report discusses the potential for thallium-201 (Tl-201) patients to activate passive radiation alarms days to weeks after nuclear stress tests, even while shielded inside industrial vehicles away from sensors. Characteristics of Tl-201, as used for medical imaging, are described. This patient was twice detained by Homeland Security Agents and searched after he activated radiation detectors at a seaport security checkpoint. Security agents deemed him not to be a threat, but they expressed concern regarding his health and level of personal radioactivity. The patient was subsequently barred from his job and sent to the hospital. Tl-201 is a widely used radioisotope for medical imaging. The radioactive half-life of Tl-201 is 73.1h, however, reported periods of extended personal radiation have been seen as far out as 61 days post-administration. This case describes an anxious, but otherwise asymptomatic patient presenting to the ED with detection of low-level personal radiation. Documentation should be provided to and carried by individuals receiving radionuclides for a minimum of five to six half-lives of the longest-lasting isotope provided. Patients receiving Tl-201 should understand the potential for security issues; reducing probable tense moments, confusion, and anxiety to themselves, their employers, security officials, and ED staff. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Usefulness of thallium-201 SPECT in the evaluation of tumor natures in intracranial meningiomas

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Tetsuji; Nakano, Takahiro; Asano, Kenichiroh; Shimamura, Norihito; Ohkuma, Hiroki [Hirosaki University Graduate School of Medicine, Department of Neurosurgery, Hirosaki (Japan)

    2011-11-15

    Although intracranial meningiomas are regarded as benign tumors, some of them behave clinically as malignant tumors. Past reports suggest that MIB 1 and vascular endothelial growth factor (VEGF) in postoperative tumor specimens correlate with the aggressive nature of tumors, but preoperative prediction of such a nature is more useful for therapeutic planning for the tumor. The purpose of this study was to assess the usefulness of preoperative thallium-201 chloride single-photon emission computed tomography (Tl SPECT) to evaluate biological behavior in intracranial meningiomas. Tl SPECT was performed on 39 patients with intracranial meningioma and Tl uptake indices were calculated. The difference in the Tl uptake index between atypical meningiomas and other pathological types of meningioma was evaluated. Moreover, correlation of Tl uptake indices with the MIB1 labeling index was estimated. Tl uptake indices were also compared between VEGF strongly positive and weakly positive meningiomas. The delayed index of atypical meningioma was significantly higher than that of the other pathological types (p = 0.036). Significant correlation was found between the Tl uptake index in the delayed image and MIB1 labeling index (p < 0.0001, R{sup 2} = 0.36). Moreover, VEGF strongly positive meningiomas exhibited a significantly higher Tl uptake index compared to VEGF weakly positive meningiomas in both the early image and the delayed image (p = 0.029, 0.023, respectively). Tl uptake index may be a possible preoperative surrogate marker of MIB1 and VEGF that is useful in detecting aggressive natures in intracranial meningiomas. (orig.)

  11. Effective removal of trace thallium from surface water by nanosized manganese dioxide enhanced quartz sand filtration.

    Science.gov (United States)

    Huangfu, Xiaoliu; Ma, Chengxue; Ma, Jun; He, Qiang; Yang, Chun; Zhou, Jian; Jiang, Jin; Wang, Yaan

    2017-12-01

    Thallium (Tl) has drawn wide concern due to its high toxicity even at extremely low concentrations, as well as its tendency for significant accumulation in the human body and other organisms. The need to develop effective strategies for trace Tl removal from drinking water is urgent. In this study, the removal of trace Tl (0.5 μg L -1 ) by conventional quartz sand filtration enhanced by nanosized manganese dioxide (nMnO 2 ) has been investigated using typical surface water obtained from northeast China. The results indicate that nMnO 2 enhanced quartz sand filtration could remove trace Tl(I) and Tl(III) efficiently through the adsorption of Tl onto nMnO 2 added to a water matrix and onto nMnO 2 attached on quartz sand surfaces. Tl(III)-HA complexes might be responsible for higher residual Tl(III) in the effluent compared to residual Tl(I). Competitive Ca 2+ cations inhibit Tl removal to a certain extent because the Ca 2+ ions will occupy the Tl adsorption site on nMnO 2 . Moreover, high concentrations of HA (10 mgTOC L -1 ), which notably complexes with and dissolves nMnO 2 (more than 78%), resulted in higher residual Tl(I) and Tl(III). Tl(III)-HA complexes might also enhance Tl(III) penetration to a certain extent. Additionally, a higher pH level could enhance the removal of trace Tl from surface water. Finally, a slight increase of residual Tl was observed after backwash, followed by the reduction of the Tl concentration in the effluent to a "steady" state again. The knowledge obtained here may provide a potential strategy for drinking water treatment plants threatened by trace Tl. Copyright © 2017. Published by Elsevier Ltd.

  12. Reduced left ventricular cavitary activity ("black hole sign") in thallium-201 SPECT perfusion images of anteroapical transmural myocardial infarction.

    Science.gov (United States)

    Civelek, A C; Shafique, I; Brinker, J A; Durski, K; Weiss, J L; Links, J M; Natarajan, T K; Ozguven, M A; Wagner, H N

    1991-11-01

    Apparently reduced left ventricular (LV) cavitary thallium activity in both planar and tomographic perfusion images has been previously observed by these and other investigators. With single-photon emission computerized tomography, we have clinically noted that this "black hole sign" was associated with an aneurysm in the setting of a transmural anterior or anteroapical perfusion defect. We have now prospectively studied the etiology and predictive value of this sign in 84 consecutive patients with an anterior, anteroapical transmural perfusion defect. Of the 84 patients, 49 had both LV aneurysm (confirmed by contrast ventriculography, echocardiography or gated blood pool studies) and a black hole sign. Only 1 patient with an aneurysm did not have the black hole sign, and 2 without aneurysm did. Thus, it is concluded that this sign is highly accurate in diagnosing LV aneurysm. Because thallium-201 single-photon emission computerized tomography imaging is often performed as one of the first diagnostic tests soon after myocardial infarction, this has important clinical management implications.

  13. The analysis of thallium in geological materials by radiochemical neutron activation and x-ray fluorescence spectrometry: a comparison

    Energy Technology Data Exchange (ETDEWEB)

    McGoldrick, P.J.; Robinson, P. [Tasmania Univ., Sandy Bay, TAS (Australia)

    1993-12-31

    Carrier-based radiochemical neutron activation (RNAA) is a precise and accurate technique for the analysis of Tl in geological materials. For about a decade, until the mid-80s, a procedure modified from Keays et al. (1974) was used at the University of Melbourne to analyse for Tl in a wide variety of geological materials. Samples of powdered rock weighing several hundred milligrams each were irradiated in HIFAR for between 12 hours and 1 week, and subsequently fused with a sodium hydroxide - sodium peroxide mixture and several milligrams of inactive Tl carrier. Following acid digestion of the fusion mixture anion exchange resin was used to separate Tl from the major radioactive rock constituents. The Tl was then stripped from the resin and purified as thallium iodide and a yield measured gravimetrically. Activity from {sup 204}Tl (a {beta}-emitter with a 3 8 year half-life) was measured and Tl determined by reference to pure chemical standards irradiated and processed along with the unkowns. Detection limits for the longer irradiations were about one part per billion. Precision was monitored by repeat analyses of `internal standard` rocks and was estimated to be about five to ten percent (one standard deviation). On the other hand, X-ray fluorescence spectrometry (XRF) was seen as an excellent cost-effective alternative for thallium analysis in geological samples, down to 1 ppm. 6 refs. 1 tab., 1 fig.

  14. Pentoxifylline (Trental) does not inhibit dipyridamole-induced coronary hyperemia: Implications for dipyridamole-thallium-201 myocardial imaging

    Energy Technology Data Exchange (ETDEWEB)

    Brown, K.A.; Slinker, B.K. (Univ. of Vermont College of Medicine, Burlington (USA))

    1990-06-01

    Dipyridamole-thallium-201 imaging is often performed in patients unable to exercise because of peripheral vascular disease. Many of these patients are taking pentoxifylline (Trental), a methylxanthine derivative which may improve intermittent claudication. Whether pentoxifylline inhibits dipyridamole-induced coronary hyperemia like other methylxanthines such as theophylline and should be stopped prior to dipyridamole-thallium-201 imaging is unknown. Therefore, we studied the hyperemic response to dipyridamole in seven open-chest anesthetized dogs after pretreatment with either pentoxifylline (0, 7.5, or 15 mg/kg i.v.) or theophylline (3 mg/kg i.v.). Baseline circumflex coronary blood flows did not differ significantly among treatment groups. Dipyridamole significantly increased coronary blood flow before and after 7.5 or 15 mm/kg i.v. pentoxifylline (p less than 0.002). Neither dose of pentoxifylline significantly decreased the dipyridamole-induced hyperemia, while peak coronary blood flow was significantly lower after theophylline (p less than 0.01). We conclude that pentoxyifylline does not inhibit dipyridamole-induced coronary hyperemia even at high doses.

  15. Thallium-201 scintigraphy after dipyridamole infusion with low-level exercise. III Clinical significance and additional diagnostic value of ST segment depression and angina pectoris during the test

    NARCIS (Netherlands)

    G-J. Laarman (GertJan); P.W.J.C. Serruys (Patrick); J.F. Verzijlbergen (Fred); C.A.P.L. Ascoop (Carl); J. Azar

    1990-01-01

    textabstractIntravenous dipyridamole thallium testing is a useful alternative procedure for assessing coronary artery disease (CAD) in patients who are unable to perform maximal exercise tests. Ischaemic ST segment depression and angina pectoris are frequently observed during the test, in particular

  16. Indium-111 antimyosin antibody imaging and thallium-201 imaging. A comparative myocardial scintigraphic study using single-photon emission computed tomography in patients with myocarditis and dilated cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Takehiko; Matsumori, Akira; Nohara, Ryuji; Konishi, Junji; Sasayama, Shigetake [Kyoto Univ. (Japan). Faculty of Medicine; Tamaki, Nagara

    1997-10-01

    Indium-111 antimyosin antibody imaging (a tracer of myocardial necrosis) and thallium-201 imaging (a tracer of myocardial perfusion) were compared in patients with myocarditis and dilated cardiomyopathy. The distribution of each tracer and antimyosin/thallium-201 overlapping were evaluated with single-photon emission computed tomography (SPECT). Scintigraphic data were classified into 5 patterns according to the distribution of both images and were compared with histologic findings of endomyocardial biopsy: AM-D, intense and diffuse antimyosin uptake and no perfusion abnormality (active myocarditis); AM-L, localized antimyosin uptake and no perfusion abnormality (active myocarditis); HM, no antimyosin uptake with or without perfusion abnormality (healed myocarditis); DCM-NH, diffuse antimyosin uptake and inhomogeneous thallium-201 uptake (dilated cardiomyopathy); DCM-PD, diffuse or localized antimyosin uptake and myocardial perfusion defect(s) (dilated cardiomyopathy). Patients with dilated-phase hypertrophic cardiomyopathy were frequently found in the DCM-PD group. Taken together, comparative antimyosin/thallium-201 SPECT images are useful for evaluating the activity of myocarditis and ongoing myocardial damage even in areas with no perfusion in patients with dilated cardiomyopathy. (author)

  17. Thallium-201 myocardial scintigraphy in patients with normal coronary arteries and normal left ventriculogram. Comparison with hemodynamic, metabolic and morphologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Loesse, B.; Kuhn, H.; Rafflenbeul, D.; Kroenert, H.; Hort, W.; Feinendegen, L.E.; Loogen, F.

    1980-01-01

    36 consecutive patients with chest pain and/or severe ventricular dysrhythmias, but normal coronary arteries and normal left ventriculogram, underwent thallium-201 myocardial imaging at rest and during exercise. The myocardial scintigram was abnormal in 27 patients (group A) and normal in only 9 patients (group B).

  18. Preconcentration of thallium (I) by single drop microextraction with electrothermal atomic absorption spectroscopy detection using dicyclohexano-18-crown-6 as extractant system.

    Science.gov (United States)

    Chamsaz, Mahmoud; Arbab-Zavar, Mohammad Hossien; Darroudi, Abolfazl; Salehi, Thiery

    2009-08-15

    A simple single drop liquid-phase microextraction (SDME) technique, combined with electrothermal atomic absorption spectroscopy (ETAAS) is developed both to preconcentrate and determine thallium (I) ions in aqueous solutions. The ions were transferred from 10.0 ml of aqueous sample (donor phase) containing 0.5 ml of 1% picric acid as the ion-pair agent into a 3 microl microdrop of nitrobenzene (acceptor phase) containing dicyclohexano-18-crown-6 as the complexing agent. The latter will help to improve the extraction efficiency of the analyte. After the ions have been extracted, the acceptor drop was directly injected into a graphite furnace for thallium (I) determination. Several parameters such as the extracting solvent, extraction time, temperature, concentration of picric acid and crown ether, drop volume and stirring rate were examined. Under the optimized experimental conditions, the detection limit (L.O.D.) was 0.7 ng ml(-1). The relative standard deviation for five replicate analysis of 10 ng ml(-1) of thallium (I) was 5.1%. The calibration curve was linear in the range of 3-22 ng ml(-1). The results for determination of thallium in reference material, spiked tap water and seawater demonstrated the accuracy, recovery and applicability of the presented method. The enrichment factor was 50.

  19. Synthesis and application of a novel nanostructured ion-imprinted polymer for the preconcentration and determination of thallium(I) ions in water samples

    Energy Technology Data Exchange (ETDEWEB)

    Fayazi, M., E-mail: maryamfayazi64@yahoo.com [Young Researchers and Elite Club, Kerman Branch, Islamic Azad University, Kerman (Iran, Islamic Republic of); Ghanei-Motlagh, M. [Young Researchers and Elite Club, Kerman Branch, Islamic Azad University, Kerman (Iran, Islamic Republic of); Taher, M.A. [Department of Chemistry, Faculty of Sciences, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Ghanei-Motlagh, R. [Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad (Iran, Islamic Republic of); Salavati, M.R. [Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad (Iran, Islamic Republic of)

    2016-05-15

    Highlights: • A novel nanostructured thallium(I)-imprinted polymer was evaluated for trace detection of Tl(I). • The prepared sorbent displayed rapid extraction rate, high sensitivity and good reproducibility. • The proposed methodology was applied for quantification of Tl(I) in different water samples. - Abstract: A novel synthesized nanostructured ion-imprinted polymer (IIP) was investigated for the determination of trace amount of thallium(I). For this purpose, the thallium(I) IIP particles were synthesized using methacrylic acid (MAA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the cross-linker, methyl-2-[2-(2-2-[2-(methoxycarbonyl) phenoxy] ethoxyethoxy) ethoxy] benzoate as the chelating agent and 2,2-azobisisobutyronitrile (AIBN) as the initiator. The prepared IIP particles were characterized by field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR) and thermo gravimetric analysis (TGA). Various experimental factors such as pH, the amount of IIP particles, sorption and desorption time, sample volume, elution condition, and potentially interfering ions systematically examined. Under the optimum conditions, a sensitive response to Tl(I) within a wide concentration range (0.05–18 μg L{sup −1}) was achieved. The limit of detection (LOD, 3S{sub b}/m) was 6.3 ng L{sup −1}. The maximum adsorption capacity of the novel imprinted adsorbent for Tl(I) was calculated to be 18.3 mg g{sup −1}. The relative standard deviation (RSD) for eight replicate detections of 0.1 μg L{sup −1} of thallium(I) was found to be 4.0%. An enrichment factor (EF) of 100 was obtained by this method. The proposed technique was successfully applied to monitoring thallium in different water samples and the certified reference material.

  20. Tracing subducted sediment inputs to the Ryukyu arc-Okinawa Trough system: Evidence from thallium isotopes

    Science.gov (United States)

    Shu, Yunchao; Nielsen, Sune G.; Zeng, Zhigang; Shinjo, Ryuichi; Blusztajn, Jerzy; Wang, Xiaoyuan; Chen, Shuai

    2017-11-01

    Sediments are actively subducted in virtually every arc worldwide. However, quantifying their contributions to arc lavas and thereby establishing budgets of how sediments participate in slab-mantle interaction is challenging. In this contribution we use thallium (Tl) abundances and isotopic compositions of lavas from the Ryukyu arc (including south Kyushu) and its back-arc basin, Okinawa Trough, to investigate the influence of sediments from arc to back-arc. We also present extensive geochemical data for sediments and altered oceanic crust (AOC) outboard of the northern (DSDP Sites 296, 442B, 443 and 444) and central (DSDP Sites 294 and 295) part of the Ryukyu arc. The Tl isotopic compositions of sediments change systematically from lighter outboard of northern Ryukyu arc to heavier outboard of central Ryukyu arc. The feature reflects the dominance of terrigenous material and pelagic sedimentation outboard of the northern and central Ryukyu arc, respectively. Central and northern sections of Ryukyu arc and Okinawa Trough display larger range of Tl isotopic variation than southern section, which is consistent with more pelagic provenance for sediments outboard of central and northern Ryukyu arcs than that of expected sediments outboard of southern Ryukyu arc. Identical Tl, Sr, Nd and Pb isotope variations are found when comparing arc and back arc lavas, which indicates that sediments fluxes also account for the Tl isotopic variations in the Okinawa Trough lavas. Two-end-member mixing models of Tl with Pb, Sr and Nd isotopes require sediment inputs ofsediment end members predict very similar sediment fluxes when using Tl, Sr, Nd and Pb isotopes, which indicates that fractionation of these elements must have happened after mixing between mantle and sediments. This conclusion is corroborated by model calculations of mixing between sediment melts with fractionated Sr/Nd ratios and mantle wedge, which show that no arc lava plot on such mixing lines. Thus bulk sediment

  1. Comparison of arbutamine stress and treadmill exercise thallium-201 SPECT: Hemodynamics, safety profile and diagnostic accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Kiat, H.; Berman, D.S. [Cedars-Sinai Medical Centre, Los Angeles, California, LA (United States)

    1998-02-01

    Full text: Arbutamine (ARB), a new pharmacologic stress agent with enhanced chronotropic property compared to dobutamine, was compared with treadmill (TM) exercise testing (Ex) in a multicenter study using thallium-201 (Tl) SPECT. Of the total of 184 patients who underwent ARB, 69 also had TM stress and quantitative coronary angiography. Fifty-eight patients with a low pretest likelihood of CAD also underwent ARB study for evaluation of test specificity (normalcy rate). Tl scans were scored by a central laboratory using a 20 segment (seg)/scan visual analysis (5 point system: 0=normal, 4-absent uptake). Maximum heart rate (HR) by ARB and Ex was 122 vs 141 bpm (p<0.05). Mean %HR change from baseline was similar (79% vs 82%, respectively, p=ns). Maximum systolic BP for ARB and Ex was 173 vs 175 mmHg, and mean % change from baseline was 24% vs 28% (p=ns). Sensitivity for detecting CAD (270% stenosis) by ARB Tl was 94% and 97% by Ex Tl (p=ns). Stress Tl SPECT segmental agreement for presence of defect between ARB and Ex was 92% (kappa=0.8, p<0.001). Exact segmental stress Tl score (0-4 grading) agreement was 83 % (kappa=0.7, p<0.001). Among 346 segs with stress defects by both ARB and Ex defect reversibility agreement was 86% (kappa=0.7, p<0.001). The normalcy rate for ARB TI-SPECT among patients with a low likelihood of CAD was 90%. Adverse events were mostly mild (tremor: 23%, flushing: 10%, headache: 10%, paraesthesia: 8%, dizziness: 8%, hot flushes: 4%). Arrhythimia of clinical concern occurred in 8% (10/122) of ARB patients who had cardiac catheterisation and in 1.4% (1/69) of patients who had stress Tl. Of all 184 patients with ARB stress, ARB was discontinued due to arrhythmia in 7(5%) and 1 patient had IV Metoprolol for frequent ventricular couplets. Sustained arrhythmias were not observed

  2. Geochemical translocation of thallium in the sediments from the North River, China

    Science.gov (United States)

    Liu, J.

    2016-12-01

    Thallium (Tl) is a highly toxic rare heavy metal. As a sulphophile element, it usually occurs in numerous sulphide minerals (such as pyrite, galena, sphlerite). Guangdong north region, known as the hometown of nonferrous metals, has abundant containing Tl mineral resources. Numerous industrial activities, such as mining, smelting, and electroplating are also flourishing. In 2010, a serious Tl pollution in the North River (a major river in the Northern Guangdong Province) shocked the society. The Tl pollution in water appeared to be under control after that incident. But in fact, even if the wastewater discharge of pollution sources has been controlled, the potential risk of heavy metal pollution in the sediments of the North River still exists, for the metals are easy to precipitate and accumulate into sediment from water. So far, Tl pollution in sediments has been studied to a very limited extent. In this paper, we investigated the content and vertical distribution characteristics of Tl and some other related heavy metals in a typical sediment profile from the North River by using inductively coupled plasma mass spectrometry (ICP-MS). Then the Pb isotopic compositions in the sediments were measured by using multi-inductively coupled plasma mass spectrometry (MC-ICP-MS). Several sediments from typical layers were also subjected to sequential extraction procedure for investigating the geochemical fractions of Tl. The risk of Tl and other metal pollution was finally assessed by calculating geo-accumulation indexes (Igeo) and potential ecological risk. The results showed that: (1) Tl concentrations range 1.03 mg/kg to 3.13 mg/kg with a mean of 1.89 mg/kg, three times higher than that in local background soil; (2) Tl content generally increased with depth with some fluctuations and significant correlations were found between Tl and Pb, Zn, Cd, Cu, and Ni; (3) About 46 % to 70 % in sediment cores were resided in the residual fraction; (4) Igeo showed that the studied

  3. Source and distribution of sedimentary thallium in the Bohai Sea: Implications for hydrodynamic forces and anthropogenic impact

    Science.gov (United States)

    Hu, Ningjing; Liu, Jihua; Shi, Xuefa

    2015-04-01

    Source and distribution of sedimentary thallium in the Bohai Sea: Implications for hydrodynamic forces and anthropogenic impact Hu Ningjing, Liu Jihua, Shi Xuefa First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China Thallium (Tl), a non-essential and highly toxic trace metal, is listed as priority toxic pollutant by the United States Environmental Protection Agency (USEPA) (Keith and Telliard, 1979). However, its geochemical cycling in aquatic environment has received far less attention than that of many other trace metals. This has been attributed to relatively little commercial interest in Tl and, until recently, problems inherent in its detection at environmental concentrations (Meeravali and Jiang, 2008). In this study, we investigated the sources, distribution and fate of Tl in surface sediments of the Bohai Sea (BS), China, based on the datasets of total Tl and chemical speciation of Tl of 408 surface sediment samples in the total entire BS. The enrichment factors and chemical speciation of Tl indicated that Tl in BS was dominated by natural Tl, although anthropogenic Tl contamination was observed in the Liuguhe River mouth; the mud deposits are the sinks of Tl and the regional currents and tide systems play a key role on the accumulation of Tl in BS. The distribution of Tl consistent with that of MnO and Fe2O3 as well as the level of Fe-Mn fraction is relatively high, indicating MnO and Fe2O3 influence the geochemical behaviors of Tl in the BS. Although the positive correlation between Tl and TOC is observed for the samples in the BS, however, level of Tl in oxidizable faction could be neglected, suggesting TOC might not be a major factor affecting the concentration of Tl in BS. The low proportion of Tl in the non-residual fraction dominated by the Fe-Mn oxides suggested that the labile Tl was controlled by the Fe-Mn oxides and Tl has a low bioavailability and a minor potential threat to biota in BS. Acknowledgements: this work

  4. Fractionation and Mobility of Thallium in Volcanic Ashes after Eruption of Eyjafjallajökull (2010) in Iceland.

    Science.gov (United States)

    Karbowska, Bozena; Zembrzuski, Wlodzimierz

    2016-07-01

    Volcanic ash contains thallium (Tl), which is highly toxic to the biosphere. The aim of this study was to determine the Tl concentration in fractions of volcanic ash samples originating from the Eyjafjallajökull volcano. A sequential extraction scheme allowed for a study of element migration in the environment. Differential pulse anodic stripping voltammetry using a flow measuring system was selected as the analytical method to determine Tl content. The highest average content of Tl in volcanic ash was determined in the fraction entrapped in the aluminosilicate matrix (0.329 µg g(-1)), followed by the oxidizable fraction (0.173 µg g(-1)). The lowest content of Tl was found in the water soluble fraction (0.001 µg g(-1)); however, this fraction is important due to the fact that Tl redistribution among all the fractions occurs through the aqueous phase.

  5. Determination of gold, indium, tellurium and thallium in the same sample digest of geological materials by atomic-absorption spectroscopy and two-step solvent extraction

    Science.gov (United States)

    Hubert, A.E.; Chao, T.T.

    1985-01-01

    A rock, soil, or stream-sediment sample is decomposed with hydrofluoric acid, aqua regia, and hydrobromic acid-bromine solution. Gold, thallium, indium and tellurium are separated and concentrated from the sample digest by a two-step MIBK extraction at two concentrations of hydrobromic add. Gold and thallium are first extracted from 0.1M hydrobromic acid medium, then indium and tellurium are extracted from 3M hydrobromic acid in the presence of ascorbic acid to eliminate iron interference. The elements are then determined by flame atomic-absorption spectrophotometry. The two-step solvent extraction can also be used in conjunction with electrothermal atomic-absorption methods to lower the detection limits for all four metals in geological materials. ?? 1985.

  6. Comparison of glucose-insulin-thallium-201 infusion single photon emission computed tomography (SPECT), stress-redistribution-reinjection thallium-201 SPECT and low dose dobutamine echocardiography for prediction of reversible dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Sakamoto, Hiroki; Kondo, Makoto; Motohiro, Masayuki; Usami, Satoru [Shimada Municipal Hospital, Shizuoka (Japan)

    2001-12-01

    The usefulness of glucose-insulin-thallium-201 (GI-Tl) infusion single photon emission computed tomography (SPECT) in predicting reversible dysfunction has not been evaluated, so the present study recruited 20 patients with regional ischemic dysfunction for investigation. All patients underwent GI-Tl SPECT, post-stress Tl reinjection imaging and low dose dobutamine echocardiography. The diagnostic accuracy of these 3 techniques in predicting functional recovery was evaluated by receiver operating characteristic (ROC) analysis. In segments with functional recovery, regional Tl activities of GI-Tl SPECT were significantly higher than those of reinjection imaging (p<0.05), although there were no significant differences in segments without recovery. The area under the ROC curve for GI-Tl SPECT (0.75{+-}0.06) was greater than that for reinjection imaging (0.68{+-}0.07). The optimal cutoff values to identify viable myocardium were considered to be 55% of peak activity for GI-Tl SPECT and 50% for reinjection imaging. At this cutoff point, the sensitivity and specificity for detection of functional recovery were, respectively, 85% and 61% for GI-Tl SPECT, and 73% and 61% for reinjection imaging. Dobutamine echocardiography had the same sensitivity (85%), but lower specificity (48%) than GI-Tl SPECT. Continuous infusion of GI-Tl solution enhances regional Tl uptake compared with conventional post-stress reinjection imaging. This study suggests that GI-Tl SPECT is superior to reinjection imaging and dobutamine echocardiography in predicting functional recovery after ischemic left ventricular dysfunction. (author)

  7. Detection and dosimetry of gamma ray emitted from thallium-201 and technetium-99m based on chemiluminescence technique

    Energy Technology Data Exchange (ETDEWEB)

    Shourian, Mostafa [Laboratory of Microanalysis, Institute of Biochemistry and Biophysics, University of Tehran, P.O. Box 13145-1384, Tehran (Iran, Islamic Republic of); Tavakoli, Hassan, E-mail: tavakoli@ibb.ut.ac.i [Faculty of Medicine, Department of Physiology and Biophysics, Faculty of Medicine, Baqiyatollah University of Medical Sciences, P.O. Box 19395-6558, Tehran (Iran, Islamic Republic of); Ghourchian, Hedayatollah, E-mail: hadi@ibb.ut.ac.i [Laboratory of Microanalysis, Institute of Biochemistry and Biophysics, University of Tehran, P.O. Box 13145-1384, Tehran (Iran, Islamic Republic of); Rafiee-Pour, Hossain-Ali [Laboratory of Microanalysis, Institute of Biochemistry and Biophysics, University of Tehran, P.O. Box 13145-1384, Tehran (Iran, Islamic Republic of)

    2010-09-15

    This report describes the detection and dosimetry of gamma ray emitted from Thallium-201 ({sup 201}Tl) and Technetium-99m ({sup 99m}Tc) based on chemiluminescence technique. H{sub 2}O{sub 2} produced by two gamma emitter radioisotopes of {sup 201}Tl and {sup 99m}Tc were quantitatively measured by chemiluminescence method. Upon producing H{sub 2}O{sub 2} in a luminol alkaline solution, in the presence of diperiodatocuprate, as catalyst a chemical reaction was accrued and consequently the emitted light was measured. The determined H{sub 2}O{sub 2} concentration was correlated with the gamma ray detection and dosimetry. The sensitivity of chemiluminescence technique for {sup 201}Tl and {sup 99m}Tc dosimetry was determined to be 0.20 and 0.08 MBq/l (Mega Becquerel per liter) respectively (R.S.D. = %5, N = 3). The plotted calibration curves showed detection limits of 3.24 and 1.76 MBq/l for {sup 201}Tl and {sup 99m}Tc, respectively.

  8. Myocardial infarction diagnosis with body surface potential mapping, electrocardiography, vectorcardiography and thallium-201 scintigraphy: a correlative study with left ventriculography.

    Science.gov (United States)

    Ackaoui, A; Nadeau, R; Sestier, F; Savard, P; Primeau, R; Lemieux, R; Descary, M C

    1985-01-01

    In 35 subjects with typical or atypical angina and/or documented myocardial infarction (MI), body surface potential maps (BSPMs), ECG, VCG and rest Thallium-201 (T1-201) have been compared to left ventriculography (LVG). BSPMs were recorded with 26 ECGs, and BSPM abnormalities for MI cases were considered to be areas of normally positive potentials that have become negative. Subjects with MI were classified according to the segmental localization and degree of asynergy on LVG. Moderate anterolateral and apical asynergy were found to correlate with BSPM diagnosis of anterolateral MI and ischemia, severe anterolateral and apical asynergy with BSPM diagnosis of anterolateral MI and ischemia, and moderate diaphragmatic and/or posterobasal asynergy with BSPM diagnosis of posterior MI. Simultaneous anterior and posterior asynergy were found for BSPM diagnosis of anterior with posterior MI. Subjects with no LVG asynergy had normal BSPMs. BSPM diagnosis had the highest correlation coefficient with the LVG diagnosis (r = 0.88). ECG and VCG showed similar results with r = 0.65 and 0.71 respectively, while T1-201 had r = 0.55. The examination of our BSPMs, as well as the ECG, VCG and T1-201, did not permit to detect apical damage in presence of anterior MI, and posterobasal damage in the presence of inferoposterior MI. It is concluded that BSPMs are slightly superior to ECG and VCG for diagnosis of MI.

  9. Thallium release from acid mine drainages: Speciation in river and tap water from Valdicastello mining district (northwest Tuscany).

    Science.gov (United States)

    Campanella, Beatrice; Casiot, Corinne; Onor, Massimo; Perotti, Martina; Petrini, Riccardo; Bramanti, Emilia

    2017-08-15

    In this work we present an advantageous method for the simultaneous separation and detection of Tl(I) and Tl(III) species through ion chromatography coupled with on-line inductively coupled plasma - mass spectrometry. Chromatographic separation between Tl(III) and Tl(I) was achieved in less than two minutes. The method was validated by recovery experiments on real samples, and by comparing the sum of the concentrations of individual Tl species with total thallium values obtained from continuous flow ICP-MS. The experimental procedure offers an accurate, sensitive and interference-free method for Tl speciation at trace levels in environmental samples. This allowed us to investigate the Tl speciation in acid mine drainages (AMD), surface waters and springs in a mining catchment in Valdicastello Carducci (Tuscany, Italy), where severe Tl contamination ad been evidenced previously. This study shows for the first time that Tl(III), in addition to Tl(I), is present in considerable amounts in water samples affected by acid mining outflow, raising the question of the origin of this thermodynamically unstable species. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Electron and ligand transfer reactions between cyclometallated platinum(II) compounds and thallium(III) carboxylates

    NARCIS (Netherlands)

    Koten, G. van; Ploeg, A.F.M.J. van der; Vrieze, K.

    1982-01-01

    Reaction of trans-[(2-Me{2}NCH{2}C{6}H{4}{2}Pt}I{}I{] with Tl}I{}I{}I{(O{2}CR){3} (R = Me, i-Pr) gave direct elimination of Tl}I{(O{2}CR) and formation of the oxidative addition product [(2-Me{2}NCH{2}C{6}H{4}){2}Pt}I{}V{ (O{2}CR){2}], in two isomeric forms. A structure with the carbon ligands in

  11. Thallium dynamics in contrasting light sandy soils--soil vulnerability assessment to anthropogenic contamination.

    Science.gov (United States)

    Vanek, Ales; Chrastný, Vladislav; Komárek, Michael; Galusková, Ivana; Drahota, Petr; Grygar, Tomás; Tejnecký, Václav; Drábek, Ondrej

    2010-01-15

    The influence of different soil conditions and the presence of LMWOA (Low Molecular Weight Organic Acids) on anthropogenic Tl dynamics were discussed in this study. A shift from the "labile" to the residual fraction during the ageing was identified, indicating Tl incorporation into stable phases (e.g., illite and/or amorphous silicates). The increased water-soluble Tl concentration (1.8-fold, in maximum) after the split application of LMWOA (simulating root exudation) was observed in all soils; partial dissolution of relatively "insoluble" Tl-bearing phases (silicates and eventually oxides) in the presence of LMWOA is suggested. Thermodynamic modeling showed that Tl mobilization in the presence of citric and oxalic acids was indirect and could be attributed to complexation of major elements (Ca, Mg, Al) originating from the dissolution of various soil phases. On the contrary, H(+)-promoted dissolution by acetic acid was assumed as the predominant mechanism of Tl mobilization. Manganese(III,IV) oxides, illite and probably amorphous silicates were evaluated as the dominant phases responsible for Tl retention in the soils. In carbonate-rich soils, Tl coprecipitation with the newly formed carbonates seems to be an important factor influencing Tl release. Therefore, we suggest data on CEC, pH(ZPC) and soil mineralogy to be critical for assessment of Tl behavior in soil systems.

  12. Thallium in spawn, juveniles, and adult common toads (Bufo bufo) living in the vicinity of a zinc-mining complex, Poland

    OpenAIRE

    Dmowski, Krzysztof; Rossa, Monika; Kowalska, Joanna; Krasnodębska-Ostręga, Beata

    2014-01-01

    A breeding population of the common toad Bufo bufo living in the vicinity of a Zn-Pb smelting works in Bukowno, Poland was studied for the presence of thallium. Tl concentration was measured in the bottom sediments of the spawning pond, in the laid eggs, in juveniles after metamorphosis, and in the selected tissues of the adult individuals. A very high concentration of Tl was detected in the spawn (13.97 ± 8.90 mg/kg d.w.). In 50 % of the spawn samples, levels exceeded 20 mgTl/kg d.w. The iss...

  13. Effects of potassium channel opener on the kinetics of thallium-201 in in-vitro and in-vivo

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.; Kim, E. J.; Ahn, B. C.; Chae, S. C.; Lee, K. B. [College of Medicine, Kyungpook National Univ., Taegu (Korea, Republic of); Kim, C. K. [Mt. Sinai Medical School, New York (United States)

    1997-07-01

    Potassium channel opener (K-opener) opens membrane ATP-sensitive K{sup +}-channel and induces and increase in potassium efflux from cells. K-openers are powerful smooth muscle relaxants and currently used as antihypertensive, antianginal drugs or bronchodilators in clinic. Pharmacologic potency of newly synthesized K-opener is being evaluated with efflux capacity of preincubated Rb-83 from the isolated aortic vascular tissue preparation. Thallium has similar characteristics to those of rubidium and potassium in vivo. To evaluate the effect of pinacidil (a potent K-opener) on Tl-201 biokinetics, we have performed uptake/washout studies in cultured myocytes, and mice biodistribution study. Primary culture of spontaneous contracting myocytes was undertake from hearts of newborn Sprague-Dawley rat. Different concentration of pinacidil (100nM or 10uM) was co-incubated with Tl-201 in HBSS buffer to evaluate its effect on cellular uptake, or challenged to myocyte preparations pre-incubated with Tl-201 for washout study. Pinacidil was injected into mice simultaneous or 10-min after Tl-201 injection, and organ uptake and whole body retention ratio was measured using gamma counter or dose calibrator. Co-incubation of pinacidil with Tl-201 resulted in a decrease in Tl uptake into myocytes by 1.6 - 2.5 times, and an increase in washout by 1.6 - 3.1 times. Pinacidil injection resulted in mild decrease in blood, heart and liver uptake in mice, bur renal uptake was markedly decreased in a dose dependent manner. These results suggest that the pinacidil Tl-201 kinetics and may potentially affect the interpretation of Tl-201 myocardial imaging.

  14. Functional Significance of Angiographic Collaterals in Patients with Totally Occluded Right Coronary Artery: Intracoronary Thallium-201 Scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Do Yun; Lee, Jong Doo; Cho, Seung Yun; Shim, Won Heum; Ha, Jong Won; Kim, Han Soo; Kwon, Hyuk Moon; Jang, Yang Soo; Chung, Nam Sik; Kim, Sung Soon [Yonsei University College of Medicine, Seoul (Korea, Republic of); Park, Chang Yun; Kim, Young Soo [Inje University College of Medicine, Seoul (Korea, Republic of)

    1993-07-15

    To compare the myocardial viability in patients suffering from total occlusion of the right coronary artery (RCA) with the angiographic collaterals, intracoronary injection of Thallium-201 (T1-201) was done to 14 coronary artery disease (CAD) patients (pts) with total occlusion of RCA and into four normal subjects for control. All 14 CAD pts had Grade 2 or 3 collateral circulations. There were 14 male and 4 females, and their ages ranged from 31 to 70 years. In nine pts, T1-201 was injected into left main coronary artery (LCA) (300 approx 350 mu Ci) to evaluate the myocardial viability of RCA territory through collateral circulations. The remaining five pts received T1-201 into RCA (200-250 mu Ci) because two had intraarterial bridging collaterals and three had previous successful PTCA. Planar and SPECT myocardial perfusion images were obtained 30 minutes, and four to five hours after T1-201 reinjection. Intravenous T1-201 reinjection (six pts) or {sup 99m}Tc-MIBI (two pts) were also performed in eight CAD pts. Intracoronary myocardial perfusion images were compared with intravenous T1-201(IV T1-201) images, EGG, and ventriculography. Intracoronary TI-201 images proved to be superior to that of IV T1-201 due to better myocardial to background uptake ratio and more effective in the detection of viable tissue. We also found that perfusion defects were smaller on intracoronary T1-201 images than those on the IV T1-201. All of the 14 CAD pts had either mostly viable myocardium (seven pts) or large area of T1-201 perfusion (seven pts) in RCA territory, however ventriculographic wall motion and ECG did not correlate well with intracoronary myocardial perfusion images. In conclusion, total RCA occlusion patients with well developed collateral circulation had large area of viable myocardial in the corresponding territory.

  15. Disease stage classification in hypertrophic cardiomyopathy by dual analysis of iodine-123-labeled metaiodobenzylguanidine and thallium-201 myocardial scintigraphies

    Energy Technology Data Exchange (ETDEWEB)

    Hiasa, Go [Ehime Univ., Matsuyama (Japan). School of Medicine

    2001-08-01

    Many patients with hypertrophic cardiomyopathy (HCM) gradually changes from typical myocardial hypertrophy to dilated cardiomyopathy-like features. However, it is difficult to estimate the disease stage in HCM. To determine the disease stage, dual analysis of iodine-123-labeled metaiodobenzylguanidine ({sup 123}I-MIBG) and thallium-201 ({sup 201}Tl) myocardial scintigraphies were performed in 108 HCM patients. According to the scintigraphic distribution patterns, patients were divided into three groups. Group A (n=15): normal distributions of both {sup 123}I-MIBG and {sup 201}Tl, group B (n=71): normal {sup 201}Tl and low {sup 123}I-MIBG patterns, group C (n=22): low distributions of both scintigraphies. The decrease in {sup 201}Tl uptake was observed in only group C. Concerning {sup 123}I-MIBG, heart-to-mediastinum ratio (H/M) and washout rate (WOR) had good correlations with left ventricular systolic functions. H/M was decreased and WOR was increased in order of C, B and A groups. Left ventricular diastolic function reflected by isovolumic relaxation time was longer in group B than in group A. Attenuated left ventricular hypertrophy, enlarged left ventricular volumes, impaired left ventricular functions and serious clinical symptoms were observed in only group C. Myocardial sympathetic abnormalities in group B may be mainly due to myocardial hypertrophy, and those in group C may be due to myocardial injury. Dual analysis of {sup 123}I-MIBG and {sup 201}Tl scintigraphies may be useful to classify disease stages of HCM. (author)

  16. New quaternary thallium indium germanium selenide TlInGe2Se6: Crystal and electronic structure

    Science.gov (United States)

    Khyzhun, O. Y.; Parasyuk, O. V.; Tsisar, O. V.; Piskach, L. V.; Myronchuk, G. L.; Levytskyy, V. O.; Babizhetskyy, V. S.

    2017-10-01

    Crystal structure of a novel quaternary thallium indium germanium selenide TlInGe2Se6 was investigated by means of powder X-ray diffraction method. It was determined that the compound crystallizes in the trigonal space group R3 with the unit cell parameters a = 10.1798(2) Å, c = 9.2872(3) Å. The relationship with similar structures was discussed. The as-synthesized TlInGe2Se6 ingot was tested with X-ray photoelectron spectroscopy (XPS) and X-ray emission spectroscopy (XES). In particular, the XPS valence-band and core-level spectra were recorded for initial and Ar+ ion-bombarded surfaces of the sample under consideration. The XPS data allow for statement that the TlInGe2Se6 surface is rigid with respect to Ar+ ion-bombardment. Particularly, Ar+ ion-bombardment (3.0 keV, 5 min duration, ion current density fixed at 14 μA/cm2) did not cause substantial modifications of stoichiometry in topmost surface layers. Furthermore, comparison on a common energy scale of the XES Se Kβ2 and Ge Kβ2 bands and the XPS valence-band spectrum reveals that the principal contributions of the Se 4p and Ge 4p states occur in the upper and central portions of the valence band of TlInGe2Se6, respectively, with also their substantial contributions in other portions of the band. The bandgap energy of TlInGe2Se6 at the level of αg=103 cm-1 is equal to 2.38 eV at room temperature.

  17. Alumino-silicate catalyst and use for aromatization of hydrocarbons comprising 5 to 12 carbon atoms

    Energy Technology Data Exchange (ETDEWEB)

    Alario, F.; Deves, J.M.

    1993-05-21

    The invention describes a composite catalyst which contains: a MFI structure zeolite in the form hydrogen, containing in its structure Silicon, Aluminium and / or Gallium at least; a matrix; platinum metals at least and additive metal chosen among Stain, Germanium, Indium, Copper, Iron, Molybdenum, Gallium, Thallium, Gold, Silver, Ruthenium, Chrome, Tungsten and Lead at least; an halogen chosen among Fluorine, Chlorine, Bromine and Iodine at least; possibly, doping element chosen among Gallium and Zinc and possibly alkaline or alkaline-earth metal in the matrix preferentially. The invention describes also the use of this catalyst for aromatization reactions of hydrocarbons containing 5 to 12 carbon atoms per molecule.

  18. MFI structure catalyst and utilization for aromatization hydrocarbons comprising 5 to 12 carbon atoms

    Energy Technology Data Exchange (ETDEWEB)

    Alario, F.; Deves, J.M.

    1993-05-21

    The invention describes a composite catalyst which contains: a MFI structure zeolite containing, at least, an element chosen among alkaline or alkaline-earth metals, with a structure made of Silicon, Aluminium and / or Gallium; a matrix; platinum metals and additive metal chosen among Stain, Germanium, Indium, Copper, Iron, Molybdenum, Gallium, Thallium, Gold, Silver, Ruthenium, Chrome, Tungsten and Lead at least; an halogen chosen among Fluorine, Chlorine, Bromine and Iodine at least; Gallium and Zinc possibly; alkaline or alkaline-earth metal in the matrix preferentially. The invention describes also the use of this catalyst for aromatization reactions of hydrocarbons containing 5 to 12 carbon atoms per molecule.

  19. Synthesis, Characterization and Antibacterial Studies of N-(Benzothiazol-2-yl-4-chlorobenzenesulphonamide and Its Neodymium(III and Thallium(III Complexes

    Directory of Open Access Journals (Sweden)

    Lawrence Nnamdi Obasi

    2017-02-01

    Full Text Available N-(Benzothiazol-2-yl-4-chlorobenzenesulphonamide (NBTCS was synthesized by condensation reaction of 4-chlorobenzenesulphonyl chloride and 2-aminobenzothiazole in acetone under reflux. Neodymium(III and thallium(III complexes of the ligand were also synthesized. Both ligand and metal complexes were characterized using UV-Vis, IR, 1H- and 13C-NMR spectroscopies, elemental analysis and molar conductance measurement. IR studies revealed that the ligand is tridentate and coordinates to the metal ions through nitrogen and oxygen atoms of the sulphonamide group and nitrogen atom attached to benzothiazole ring. The neodymium(III complex displays a coordination number of eight while thallium(III complex displays a coordination number of six. The ligand and its complexes were screened in vitro for their antibacterial activities against Escherichia coli strains (E. coli 6 and E. coli 13, Proteus species, Staphylococcus aureus and Pseudomonas aeruginosa using the agar well diffusion technique. The synthesized compounds were found to be more active against the microorganisms screened relative to ciprofloxacin, gentamicin and co-trimoxazole.

  20. Comparative study of body surface isopotential map, left ventriculogram and thallium-201 myocardial scintigram in patients with old lateral myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Naoyuki

    1988-01-01

    In 16 patients with old lateral myocardial infarction, body surface isopotential maps and 12 lead electrocardiograms were compared with left ventriculographic findings. In addition 8 of these subjects were performed thallium-201 myocardial scintigraphy in order to determine the location and extent of myocardial necrosis. Common 12 lead electrocardiographic findings of the subjects were initial Q waves more than 30 msec and inverted T waves in only aVL lead. The patients were classified into 4 groups according to the location and extent of ventricular wall motion abnormalities group I (6 cases) showed hypokinesis in the anterior segment, group II (5 cases): akinesis in the anterior segment and hypokinesis in the seg. 6, group III (4 cases): hypokinesis in the anterior segment and seg. 7, group IV (1 case): hypokinesis in the anterior segment and seg. 4, 7. And each of the 4 groups demonstrated characteristic findings of surface isopotential maps. Group II with coexisting hypokinesis in the seg. 6 showed surface isopotential maps additional pattern of anterior myocardial infarction, and group III with coexisting hypokinesis in the seg. 7 showed additional patterns of posterior myocardial infarction. The classification according to the abnormality of ventricular wall motion was also conformed with the thallium-201 myocardial scintigraphic findings except one case. These results suggest that body surface isopotential map is more useful than the 12 lead electrocardiogram in detecting the location and extent of left ventricular wall motion abnormality in patients with old lateral myocardial infarction. (author) 53 refs.

  1. Serial thallium-201 imaging at rest in patients with unstable and stable angina pectoris: relationship of myocardial perfusion at rest to presenting clinical syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Brown, K.A.; Okada, R.D.; Boucher, C.A.; Phillips, H.R.; Strauss, H.W.; Pohost, G.M.

    1983-07-01

    In order to determine whether there are differences in myocardial perfusion at rest among patients with various unstable and stable angina syndromes, serial thallium-201 imaging was performed at rest in 19 patients presenting with rapidly worsening exertional angina (unstable angina, group A), 12 patients with rest angina alone without exertional symptoms (unstable angina, group B), and 34 patients with chronic stable angina. No patient had an episode of angina within 4 hours of study. Nineteen of 19 (100%) patients in group A demonstrated transient defects compared to only 3 of 12 (25%) patients in group B (p less than 0.0001) and 4 of 34 (12%) stable angina patients (p less than 0.0001). The majority of zones demonstrating transient defects in group A were associated with hypokinesis of the corresponding left ventriculogram segment without associated ECG evidence of previous infarction. There were no significant differences in the frequency of persistent thallium defects, severity of angiographic coronary artery disease, or frequency of regional wall motion abnormalities of myocardial segments supplied by stenotic coronary arteries among the three groups of patients. Transient defects have been shown to reflect reduction in regional coronary blood flow to viable myocardium. Therefore, we conclude that regional resting hypoperfusion of viable myocardium is far more common in patients with exertional unstable angina symptoms than in patients with rest angina alone or chronic stable angina.

  2. Aromatization process of hydrocarbons containing 2 to 4 carbon atoms in the presence of alumino-silicate catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Alario, F.; Deves, J.M.

    1993-05-21

    The invention describes an aromatization process of hydrocarbons comprising 2 to 4 carbon atoms per molecule in the presence of a composite catalyst which contains: a MFI structure zeolite in the form hydrogen, containing in its structure Silicon, Aluminium and / or Gallium at least; a matrix; platinum metals at least and additive metal chosen among Stain, Germanium, Indium, Copper, Iron, Molybdenum, Gallium, Thallium, Gold, Silver, Ruthenium, Chrome, Tungsten and Lead at least; an halogen chosen among Fluorine, Chlorine, Bromine and Iodine at least; doping element chosen among Gallium and Zinc possibly and possibly alkaline or alkaline-earth metal.

  3. Aromatization process of hydrocarbons containing 2 to 4 carbon atoms in the presence of MFI structure zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Alario, F.; Deves, J.M.

    1993-05-21

    The invention describes an aromatization process of hydrocarbons comprising 2 to 4 carbon atoms per molecule in the presence of a composite catalyst which contains: a MFI structure zeolite containing an element chosen among alkaline or alkaline-earth metals, with a structure made of Silicon, Aluminium and / or Gallium; a matrix; platinum metals and additive metal chosen among Stain, Germanium, Indium, Copper, Iron, Molybdenum, Gallium, Thallium, Gold, Silver, Ruthenium, Chrome, Tungsten and Lead at least; an halogen chosen among Fluorine, Chlorine, Bromine and Iodine at least; Gallium and Zinc possibly; alkaline or alkaline-earth metal in the matrix preferentially. The invention describes also catalyst preparation and use for hydrocarbons aromatization reactions.

  4. Syndrome of diminished vasodilator reserve of the coronary microcirculation (microvascular angina or syndrome X): Diagnosis by combined atrial pacing and thallium 201 imaging--a case report

    Energy Technology Data Exchange (ETDEWEB)

    Magarian, G.J.; Palac, R.; Reinhart, S. (Veterans Administration Medical Center, Portland, OR (USA))

    1990-08-01

    Patients with angina-like chest pain without evidence of epicardial coronary artery disease or coronary arterial vasospasm are becoming increasingly recognized. These are often related to noncardiac causes including esophageal, musculoskeletal, and hyperventilatory or panic states. However, recently a subgroup of such patients are being recognized as having true myocardial ischemia and chest pain on the basis of diminished coronary microvascular vasodilatory reserve (microvascular ischemia or Syndrome X). The authors describe such a patient who was found to have replication of anginal pain associated with a reversible ischemic defect on thallium 201 imaging during atrial pacing, suggesting ischemia in this myocardial segment. Resolution of angina and ST segment electrocardiographic changes of ischemia occurred with cessation of pacing. We believe this is the first report of a patient with this form of myocardial ischemia diagnosed by this method and should be considered in patients with anginal chest pain after significant coronary artery disease and coronary vasospasm have been excluded.

  5. Determination of perfusion defect area in experimental myocardial infarction. A comparison between 201-thallium and sup 99m Tc methoxy-isobutyl-isonitril (MIBI)

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, K.D.; Rohmann, S.; Bahavar, H.; Grebe, S.F.; Schaper, W.; Schlepper, M. (Kerckhoff-Klinik, Bad Nauheim (Germany))

    1991-08-01

    To assess the accuracy of two myocardial perfusion markers in quantifying defect size, the left anterior descending coronary artery (LAD) was occluded in 13 porcine hearts. Fourty minutes later 55 MBq {sup 201}TI and 370 MBq {sup 99m}Tc-MIBI were simultaneously injected i.v. in 10 animals. After injection and in vivo double nuclide SPECT acquisition, the risk area was demarcated with fluorescein (FI) dye in 5 animals. The in vitro defect area determined by {sup 201}TI was significant larger (15.8 {+-} 27%) than those of {sup 99m}Tc-MIBI, while FI compared to Tc showed no statistical difference. Thus, in a pig model Tc-MIBI was more accurate with ex vivo imaging. With SPECT thallium imaging defect size was overestimated. In vivo there was a distinct trend with Tc-MIBI studies to underestimate the defect size up to 16%. (orig.).

  6. High thallium content in rocks associated with Au-As-Hg-Tl and coal mineralization and its adverse environmental potential in SW Guizhou, China

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, T.F.; Guha, J.; Boyle, D. [Chinese Academy of Science, Guiyang (China)

    2004-08-15

    This study is focused on high concentrations of Tl in rocks in SW Guizhou, China, that are related to several widely scattered disseminated gold-mercury-arsenic and coal deposits, and a primary Tl deposit within an Au-As-Hg-Tl metallogenic belt of the Huijiabao anticline. The Tl, Hg and As in the Lanmuchang Hg-Tl deposit area are associated with the abundant occurrence of sulfide minerals such as lorandite, realgar, orpiment and cinnabar. Concentrations of Tl range from 100 to 35 000 ppm in sulfide ores, and 39-490 ppm in host rocks. The enrichment of Au, Tl, Hg, As, and Sb in the Yanshang gold mineralized area reflects the occurrence of Au mineralization and its mineral assemblage of Tl-Hg-As-Sb sulfides. Thallium ranges from 0.22 to 16 ppm in Au ores and host rocks. Thallium in coals is enriched up to 46 ppm within the Au-As-Hg-TI metallogenic belt, and is derived from the regional Au-As-Hg-Tl mineralization. Mercury and As show a similar distribution to Tl with high concentrations in sulfide ores, coals and host rocks. Human populations living near and downstream of Tl deposits and Tl-bearing ore deposits are susceptible to Tl contamination because of its high toxicity and high uptake rate by crops. The dispersion of Tl, Hg and As associated with the primary mineralization of Au-As-Hg-TI can be traced through physical erosion and chemical weathering, producing secondary dispersion into sods, groundwater and surface water and crops. Mining activities compound the natural processes, readily dispersing Tl into the surface environment.

  7. Functional significance of myocardial perfusion defects induced by dipyridamole using thallium-201 single-photon emission computed tomography and two-dimensional echocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Jain, A.; Suarez, J.; Mahmarian, J.J.; Zoghbi, W.A.; Quinones, M.A.; Verani, M.S. (Baylor College of Medicine, Houston, TX (USA))

    1990-10-01

    The mechanisms responsible for inhomogeneous myocardial blood flow after oral administration of a large dose (300 mg) of dipyridamole were assessed in 27 patients with serial thallium-201 single-photon emission computed tomography (SPECT) and simultaneous 2-dimensional echocardiograms. Myocardial tomographic images were obtained 50 minutes and 3 to 4 hours after administration of dipyridamole. Two-dimensional echocardiograms were recorded at baseline and then every 15 minutes for 60 minutes. Dipyridamole caused only a mild reduction in blood pressure (from 129 +/- 18 to 126 +/- 16 mm Hg) and a mild increase in heart rate (from 69 +/- 15 to 73 +/- 4 beats/min). Sixteen patients had perfusion defects after dipyridamole by SPECT, which underwent partial or total filling-in. Fourteen of these patients (87.5%) had either a new abnormality or further deterioration of a preexisting wall motion abnormality by 2-dimensional echocardiography, and thus were considered to have developed transient ischemia during dipyridamole administration. Ten of 11 patients (91%) with normal perfusion or fixed defects by SPECT had no further deterioration in wall motion after oral dipyridamole, and were thus considered to have no evidence of myocardial ischemia. In conclusion, most patients with transient thallium-201 defects after dipyridamole develop transient worsening of resting wall motion by 2-dimensional echocardiography, suggestive of true myocardial ischemia. Because myocardial oxygen demand, as indicated by the heart rate-blood pressure product, did not change significantly, the mechanism of myocardial ischemia in these patients is likely to be diminished regional blood flow related to a subendocardial steal induced by dipyridamole.

  8. Effects of Potassium-Channel Opener on Thallium-201 Kinetics: In-vitro Study in Rat Myocyte Preparations and In-vivo Mice Biodistribution Study

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Tae; Kim, Eun Ji; Ahn, Byeong Cheol; Son, Kang Kyun; Lee, Kyu Bo [Kyungpook National University School of Medicine, Taegu (Korea, Republic of); Ha, Jeoung Hee [Youngnam University Medical School, Taegu (Korea, Republic of); Kim, Chun Ki [Mt. Sinai School of Medicine, New York (United States)

    1996-10-15

    Potassium channel opener (K-opener) opens ATP-sensitive K{sup +}-channel located at membrane and induces potassium efflux from cytosol, resulting in intracellular hyperpolarization. Newly synthesized K-opener is currently examined for pharmacologic potency by means of rubidium release test from smooth muscle strip preincubated with Rb-86. Since in-vive behavior of thallium is similar to that of rubidium, we hypothesized that K-opener can alter T1-201 kinetics in vivo. This study was prepared to investigate the effects of pinacidil (one of potent K-openers) on the T1-201 uptake and clearance in cultured myocyte, and in-vivo biodistribution in mice. Spontaneous contracting myocytes were prepared to imitate in-vivo condition from 20 hearts of 3-5 days old Sprague-Dawley rat and cultured for 3-5 days before use (5 X 105 cells/ml). Pinacidil was dissolved in 10% DMSO solution at a final concentration of 100nM or 10uM and was co-incubated with T1-201 in HBSS buffer for 20-min to evaluate its effect on cellular T1-uptake, or challenged to cell preparation pre-incubated with T1-201 for washout study. Two, 40 or 100 mg of pinacidil was injected intravenously into ICR mice at 10 min after 5 muCi T1-201 injection, and organ uptake and whole body retention rate were measured at different time points. Co-incubation of pinacidil with T1-201 resulted in a decrease in T1-201 uptake into cultured myocyte by 1.6 to 2.5 times, depending on pinacidil concentration and activity of T1-201 used. Pinacidil enhanced T1-201 washout by 1.6-3.1 times from myocyte preparations pre-incubated with T1-201. Pinacidil treatment appears to be resulted in mild decreases in blood and liver activity in normal mice, in contrast, renal and cardiac uptake were mildly decreased in a dose dependent manner. Whole body retention ratios of T1-201 were lower at 24 hour after injection with 100 mg of pinacidil than control. These results suggest that treatment with K-opener may affect the interpretation of T1

  9. Determination of particle mass deposition according to Bergerhoff; Performance characteristics of the measurement of particle mass deposition and its portions of lead, cadmium, zinc and thallium. Bestimmung des Staubniederschlags nach Bergerhoff; Verfahrenskenngroessen fuer die Messung des Staubniederschlags und seiner Anteile an Blei, Cadmium, Zink und Thallium

    Energy Technology Data Exchange (ETDEWEB)

    Gehrig, R. (Eidgenoessische Materialpruefungs- und Forschungsanstalt, Duebendorf (Switzerland). Abt. fuer Luftfremdstoffe); Faesi, C. (Eidgenoessische Materialpruefungs- und Forschungsanstalt, Duebendorf (Switzerland). Abt. fuer Luftfremdstoffe); Hofer, P. (Eidgenoessische Materialpruefungs- und Forschungsanstalt, Duebendorf (Switzerland). Abt. fuer Luftfremdstoffe)

    1993-05-01

    The requirements concerning quality assurance have increased considerably in the field of immission control. Well founded values for detection limits and confidence limits have to be given. Based on the statistical analysis of long term data series of deposition measurements of particle mass (Berghoff method), lead, cadmium, zinc and thallium performance characteristics were established for very differently polluted sites. The resulting detection limits as well as confidence limits are low enough for a reliable control of the respective immission limit values. It is further shown that the use of plastic buckets instead of the glass buckets required by the VDI guideline or the addition of a protecting agent to avoid freezing does not affect the measurements significantly. (orig.)

  10. Preparation, Characterization, and In Vivo Pharmacoscintigraphy Evaluation of an Intestinal Release Delivery System of Prussian Blue for Decorporation of Cesium and Thallium

    Directory of Open Access Journals (Sweden)

    Nidhi Sandal

    2017-01-01

    Full Text Available Background. Prussian blue (PB, ferric hexacyanoferrate is approved by US-FDA for internal decorporation of Cesium-137 (137Cs and Thallium-201 (201Tl. Aim. Since PB is a costly drug, pH-dependent oral delivery system of PB was developed using calcium alginate matrix system. Methods. Alginate (Alg beads containing PB were optimized by gelation of sodium alginate with calcium ions and effect of varying polymer concentration on encapsulation efficiency and release profile was investigated. Scanning electron microscopy (SEM was carried out to study surface morphology. Adsorption efficacy of Alg-PB beads for 201Tl was evaluated and compared with native PB. In vivo pH-dependent release of the formulation was studied in humans using gamma scintigraphy. Results. Encapsulation efficiencies of Alg-PB beads with 0.5, 1.0, 1.5, and 2.0% polymer solution were 99.9, 91, 92, and 93%, respectively. SEM and particle size analysis revealed differences between formulations in their appearance and size distribution. No drug release was seen in acidic media (pH of 1-2 while complete release was observed at pH of 6.8. Dissolution data was fitted to various mathematical models and beads were found to follow Hixson-Crowell mechanism of release. The pH-dependent release of beads was confirmed in vivo by pharmacoscintigraphy in humans.

  11. Replacement of a photomultiplier tube in a 2-inch thallium-doped sodium iodide gamma spectrometer with silicon photomultipliers and a light guide

    Directory of Open Access Journals (Sweden)

    Chankyu Kim

    2015-06-01

    Full Text Available The thallium-doped sodium iodide [NaI(Tl] scintillation detector is preferred as a gamma spectrometer in many fields because of its general advantages. A silicon photomultiplier (SiPM has recently been developed and its application area has been expanded as an alternative to photomultiplier tubes (PMTs. It has merits such as a low operating voltage, compact size, cheap production cost, and magnetic resonance compatibility. In this study, an array of SiPMs is used to develop an NaI(Tl gamma spectrometer. To maintain detection efficiency, a commercial NaI(Tl 2′ × 2′ scintillator is used, and a light guide is used for the transport and collection of generated photons from the scintillator to the SiPMs without loss. The test light guides were fabricated with polymethyl methacrylate and reflective materials. The gamma spectrometer systems were set up and included light guides. Through a series of measurements, the characteristics of the light guides and the proposed gamma spectrometer were evaluated. Simulation of the light collection was accomplished using the DETECT 97 code (A. Levin, E. Hoskinson, and C. Moison, University of Michigan, USA to analyze the measurement results. The system, which included SiPMs and the light guide, achieved 14.11% full width at half maximum energy resolution at 662 keV.

  12. Myocardial scintigraphy with iodine-123 phenylpentadecanoic acid and thallium-201 in patients with coronary artery disease: a comparative dual-isotope study.

    Science.gov (United States)

    Zimmermann, R; Rauch, B; Kapp, M; Bubeck, B; Neumann, F J; Seitz, F; Stokstad, P; Mall, G; Tillmanns, H; Kübler, W

    1992-01-01

    To characterise the clinical usefulness of serial myocardial scintigraphy with iodine-123 phenylpentadecanoic acid (IPPA) in comparison with thallium-201, dual-isotope investigations were performed in 41 patients with angiographically documented coronary artery disease. Both tracers were administered simultaneously during symptom-limited ergometry. Planar scintigrams were acquired immediately after stress, and delayed imaging was performed after 1 h for IPPA and 4 h for 201Tl. Scintigrams were evaluated both qualitatively and quantitatively using a newly developed algorithm for automated image superposition. Initial myocardial uptake of both tracers was closely correlated (r = 0.75, p or = 75% (IP-PA: 70.0%, 201Tl: 66.3%, P = NS) with identical specificity (69.8%). The number of persistent defects, however, was significantly higher with IPPA (P = 0.021), suggesting that visual analysis of serial IPPA scintigrams may overestimate the presence of myocardial scar tissue. On the other hand, previous Q wave myocardial infarction was associated with a decreased regional IPPA clearance (29% +/- 11% vs 44% +/- 11% in normal myocardium, P IPPA is essentially as sensitive as scintigraphy with 201Tl for the detection of stress-induced perfusion abnormalities. Quantitative analysis of myocardial IPPA kinetics, however, is required for the evaluation of tissue viability.

  13. Dynamic low dose I-123-iodophenylpentadecanoic acid metabolic cardiac imaging; Comparison to myocardial biopsy and reinjection SPECT thallium in ischemic cardiomyopathy and cardiac transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Murray, G.L.; Magill, H.L. [Baptist Memorial Hospital (United States); Schad, N.C.

    1993-12-01

    Recognition of stunned and hibernating myocardium is essential in this era of cardiac revascularization. Positron emission tomography (PET) accurately identifies viability but is costly and unavailable to most patients. Dynamic low dose I-123-iodophenylpentadecanoic acid (IPPA) metabolic cardiac imaging is a potentially cost-effective alternative to PET. Using transmural myocardial biopsies obtained during coronary bypass surgery as the viability gold standard, resting IPPA imaging agreed with 39/43 (91%) biopsies, with a sensitivity for viability of 33/36(92%) and a specificity of 6/7 (86%) in patients with severe ischemic cardiomyopathy. Eighty percent of IPPA viable, infarcted segments improved wall motion postoperatively. Furthermore, when compared to reinjection thallium (SPECT-Tl) scans after myocardial infarction, there was IPPA-Tl concordance in 27/35 (77%)(Kappa=0.536, p=0.0003). Similar to PET, IPPA demonstrated more viability than SPECT-Tl, 26/35 (74%) vs. 18/35 (51%)(p=0.047). Finally, when compared to transvenous endomyocardial biopsy for detecting rejection following cardiac transplantation, IPPA sensitivity for {>=}Grade II rejection was 100%, and IPPA screening assessment for the necessity of biopsy could result in a 31% cost-savings. Therefore, IPPA metabolic cardiac imaging is a safe, inexpensive technique with a promising future. (author).

  14. Myocardial scintigraphy with iodine-123 phenylpentadecanoic acid and thallium-201 in patients with coronary artery disease: A comparative dual-isotope study

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, R.; Rauch, B.; Kapp, M.; Neumann, F.J.; Seitz, F.; Kuebler, W. (Heidelberg Univ. (Germany). Dept. of Cardiology); Bubeck, B. (Heidelberg Univ. (Germany). Dept. of Nuclear Medicine); Mall, G. (Heidelberg Univ. (Germany). Dept. of Pathology); Tillmanns, H. (Giessen Univ. (Germany). Dept. of Cardiology); Stokstad, P.

    1992-11-01

    To characterise the clinical usefulness of serial myocardial scintigraphy with iodine-123 phenylpentadecanoic acid (IPPA) in comparison with thallium-201, dual-isotope investigations were performed in 41 patients with angiographically documented coronary artery disease. Both tracers were adminstered simultaneously during symptom-limited ergometry. Planar scintigrams were acquired immediately after stress, and delayed imaging was performed after 1 h for IPPA and 4 h for {sup 201}Tl. Scintigrams were evaluated both qualitatively and quantitatively using a newly developed algorithm for automated image superposition. Initial myocardial uptake of both tracers was closely correlated (r=0.75, p<0.001). Both tracers also revealed a similar sensitivity for the identification of individual coronary artery stenoses {>=}75% (IPPA: 70%, {sup 201}Tl: 66.3%, P=NS) with identical specificity (69.8%). The number of persistent defects, however, was significantly higher with IPPA (P=0.021), suggesting that visual analysis of serial IPPA scintigrams may overestimate the presence of myocardial scar tissue. On the other hand, previous Q wave myocardial infarction was associated with a decreased regional IPPA clearance (29%{+-}11% vs 44%{+-}11% in normal myocardium, P<0.05). The data indicate that serial myocardial scintigraphy with IPPA is essentially as sensitive as scintigraphy with {sup 201}Tl for the detection of stress-induced perfusion abnormalities. Quantitative analysis of myocardial IPPA kinetics, however, is required for the evaluation of tissue viability. (orig.).

  15. Myocardial viability assessment with dynamic low-dose iodine-123-iodophenylpentadecanoic acid metabolic imaging: comparison with myocardial biopsy and reinjection SPECT thallium after myocardial infarction.

    Science.gov (United States)

    Murray, G L; Schad, N C; Magill, H L; Vander Zwaag, R

    1994-04-01

    Aggressive cardiac revascularization requires recognition of stunned and hibernating myocardium, and cost considerations may well govern the technique used. Dynamic low-dose (1 mCi) [123I]iodophenylpentadecanoic acid (IPPA) metabolic imaging is a potential alternative to PET using either 18FDG or 15O-water. Resting IPPA images were obtained from patients with severe ischemic cardiomyopathy, and transmural myocardial biopsies were obtained during coronary bypass surgery to confirm viability. Thirty-nine of 43 (91%) biopsies confirmed the results of the IPPA images with a sensitivity for viability of 33/36 (92%) and a specificity of 6/7 (86%). Postoperatively, wall motion improved in 80% of IPPA-viable, dysfunctional segments. Furthermore, when compared to reinjection thallium (SPECT-TI) scans after myocardial infarction, IPPA-SPECT-TI concordance occurred in 27/35 (77%) (K = 0.536, p = 0.0003). Similar to PET, IPPA demonstrated more viability than SPECT-TI, 26/35 (74%) versus 18/35 (51%) (p = 0.047). Metabolic IPPA cardiac viability imaging is a safe, inexpensive technique that may be a useful alternative to PET.

  16. Identification and Decay Studies of New, Neutron-Rich Isotopes of Bismuth, Lead and Thallium by means of a Pulsed Release Element Selective Method

    CERN Multimedia

    Mills, A; Kugler, E; Van duppen, P L E; Lettry, J

    2002-01-01

    % IS354 \\\\ \\\\ It is proposed to produce, identify and investigate at ISOLDE new, neutron-rich isotopes of bismuth, lead and thallium at the mass numbers A=215 to A=218. A recently tested operation mode of the PS Booster-ISOLDE complex, taking an advantage of the unique pulsed proton beam structure, will be used together with a ThC target in order to increase the selectivity. The decay properties of new nuclides will be studied by means of $\\beta$-, $\\gamma$- and X- ray spectroscopy methods. The expected information on the $\\beta$-half-lives and excited states will be used for testing and developing the nuclear structure models ``south-east'' of $^{208}$Pb, and will provide input data for the description of the r-process path at very heavy nuclei. The proposed study of the yields and the decay properties of those heavy nuclei produced in the spallation of $^{232}$Th by a 1~GeV proton beam contributes also the data necessary for the simulations of a hybrid accelerator-reactor system.

  17. Thallium contamination in arable soils and vegetables around a steel plant-A newly-found significant source of Tl pollution in South China.

    Science.gov (United States)

    Liu, Juan; Luo, Xuwen; Wang, Jin; Xiao, Tangfu; Chen, Diyun; Sheng, Guodong; Yin, Meiling; Lippold, Holger; Wang, Chunlin; Chen, Yongheng

    2017-05-01

    Thallium (Tl) is a highly toxic rare element. Severe Tl poisoning can cause neurological brain damage or even death. The present study was designed to investigate contents of Tl and other associated heavy metals in arable soils and twelve common vegetables cultivated around a steel plant in South China, a newly-found initiator of Tl pollution. Potential health risks of these metals to exposed population via consumption of vegetables were examined by calculating hazard quotients (HQ). The soils showed a significant contamination with Tl at a mean concentration of 1.34 mg/kg. The Tl levels in most vegetables (such as leaf lettuce, chard and pak choy) surpassed the maximum permissible level (0.5 mg/kg) according to the environmental quality standards for food in Germany. Vegetables like leaf lettuce, chard, pak choy, romaine lettuce and Indian beans all exhibited bioconcentration factors (BCF) and transfer factors (TF) for Tl higher than 1, indicating a hyperaccumulation of Tl in these plants. Although the elevated Tl levels in the vegetables at present will not immediately pose significant non-carcinogenic health risks to residents, it highlights the necessity of a permanent monitoring of Tl contamination in the steel-making areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Thallium-201 is comparable to technetium-99m-sestamibi for estimating cardiac function in patients with abnormal myocardial perfusion imaging

    Directory of Open Access Journals (Sweden)

    Ming-Che Wu

    2015-11-01

    Full Text Available We analyzed the left-ventricular functional data obtained by cardiac-gated single-photon emission computed tomography myocardial perfusion imaging (MPI with thallium-201 (Tl-201 and technetium-99m-sestamibi (MIBI protocols in different groups of patients, and compared the data between Tl-201 and MIBI. Two hundred and seventy-two patients undergoing dipyridamole stress/redistribution Tl-201 MPI and 563 patients undergoing 1-day rest/dipyridamole stress MIBI MPI were included. Higher mean stress ejection fraction (EF, rest EF, and change in EF (ΔEF were noticed in the normal MPI groups by both Tl-201 and MIBI protocols. Higher mean EF was observed in the females with normal MPI results despite their higher mean age. Comparisons between the Tl-201 and MIBI groups suggested a significant difference in all functional parameters, except for the rest end diastolic volume/end systolic volume and ΔEF between groups with negative MPI results. For the positive MPI groups, there was no significant difference in all parameters, except for the change in end diastolic volume and change in end systolic volume after stress between both protocols. The Tl-201 provides comparable left-ventricular functional data to MIBI cardiac-gated single-photon emission computed tomography in patients with positive MPI results, and may therefore be undertaken routinely for incremental functional information that is especially valuable to this patient group.

  19. Usefulness of thallium-201 myocardial scintigraphy during hyperventilation and accelerated exercise test in patients with vasospastic angina and nearly normal coronary artery

    Energy Technology Data Exchange (ETDEWEB)

    Sueda, Shozo; Mineoi, Kazuaki; Kondou, Tadashi [Takanoko Hospital, Matsuyama, Ehime (Japan)] [and others

    1998-04-01

    The usefulness of thallium-201 ({sup 201}Tl) myocardial scintigraphy was studied in 109 patients with vasospastic angina who had nearly normal coronary arteries (degree of stenosis <50%). Coronary spasm was confirmed by pharmacologic agents in all 109 patients from January 1991 to June 1996. The appearance rate of visual redistribution on {sup 201}Tl myocardial scintigraphy was compared between four groups, 34 patients performing graded bicycle ergometer exercise starting at a work load of 50 W with increments of 25 W every 3 min (Ergo(3) group), 14 patients performing hyperventilation for 5 min (HV(5) group), 31 patients performing bicycle ergometer exercise with increments of 25 W every 1 min after 5 min hyperventilation (HV(5)+Ergo(1) group), and 30 patients at rest (Rest group). The value of the visual redistribution rate on {sup 201}Tl myocardial scintigrams in the HV(5)+Ergo(l) group (65%) was higher than that in the patients of other groups (Ergo(3) 41%, HV(5) 43%, Rest 33%). However, there were no significant differences between the four groups. Stress {sup 201}Tl imaging after hyperventilation and accelerated exercise is useful to disclose ischemic evidence in about two thirds of patients with vasospastic angina and nearly normal coronary arteries, whereas about 40% of patients had visual redistribution on {sup 201}Tl myocardial scintigrams by performing standard procedures. (author)

  20. On-line preconcentration of ultra-trace thallium(I in water samples with titanium dioxide nanoparticles and determination by graphite furnace atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Saeid Asadpour

    2016-11-01

    Full Text Available A new method has been developed for the determination of Tl(I based on simultaneous sorption and preconcentration with a microcolumn packed with TiO2 nanoparticle with a high specific surface area prepared by Sonochemical synthesis prior to its determination by graphite furnace atomic absorption spectrometry (GFAAS. The optimum experimental parameters for preconcentration of thallium, such as elution condition, pH, and sample volume and flow rate have been investigated. Tl(I can be quantitatively retained by TiO2 nanoparticles at pH 9.0, then eluted completely with 1.0 mol L−1 HCl. The adsorption capacity of TiO2 nanoparticles for Tl(I was found to be 25 mg g−1. Also detection limit, precision (RSD, n = 8 and enrichment factor for Tl(I were 87 ng L−1, 6.4% and 100, respectively. The method has been applied for the determination of trace amounts of Tl(I in some environmental water samples with satisfactory results.

  1. Thallium-201 single photon emission computed tomography (SPECT) in patients with Duchenne's progressive muscular dystrophy. A histopathologic correlation study

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Toru; Yanagisawa, Atsuo; Sakata, Konomi; Shimoyama, Katsuya; Yoshino, Hideaki; Ishikawa, Kyozo [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine; Sakata, Hitomi; Ishihara, Tadayuki

    2001-02-01

    The pathomorphologic mechanism responsible for abnormal perfusion imaging during thallium-201 myocardial single photon emission computed tomography ({sup 201}Tl-SPECT) in patients with Duchenne's progressive muscular dystrophy (DMD) was investigated. Hearts from 7 patients with DMD were evaluated histopathologically at autopsy and the results correlated with findings on initial and delayed resting {sup 201}Tl-SPECT images. The location of segments with perfusion defects correlated with the histopathologically abnormal segments in the hearts. Both the extent and degree of myocardial fibrosis were severe, especially in the posterolateral segment of the left ventricle. Severe transmural fibrosis and severe fatty infiltration were common in segments with perfusion defects. In areas of redistribution, the degree of fibrosis appeared to be greater than in areas of normal perfusion; and intermuscular edema was prominent. Thus, the degree and extent of perfusion defects detected by {sup 201}Tl-SPECT were compatible with the histopathology. The presence of the redistribution phenomenon may indicate ongoing fibrosis. Initial and delayed resting {sup 201}Tl-SPECT images can predict the site and progress of myocardial degeneration in patients with DMD. (author)

  2. Iodine-123 phenylpentadecanoic acid and single photon emission computed tomography in identifying left ventricular regional metabolic abnormalities in patients with coronary heart disease: comparison with thallium-201 myocardial tomography.

    Science.gov (United States)

    Hansen, C L; Corbett, J R; Pippin, J J; Jansen, D E; Kulkarni, P V; Ugolini, V; Henderson, E; Akers, M; Buja, L M; Parkey, R W

    1988-07-01

    Iodine-123 phenylpentadecanoic acid (IPPA) is a synthetic long chain fatty acid with myocardial kinetics similar to palmitate. Two hypotheses were tested in this study. The first hypothesis was that IPPA imaging with single photon emission computed tomography (SPECT) is useful in the identification of patients with coronary artery disease. Fourteen normal volunteers (aged 27 +/- 2 years) and 33 patients (aged 54 +/- 11 years) with stable symptomatic coronary artery disease and at least one major coronary artery with luminal diameter narrowing greater than or equal to 70% were studied with symptom-limited maximal exercise testing. The IPPA (6 to 8 mCi) was injected 1 min before the termination of exercise, and tomographic imaging was performed beginning at 9 min and repeated at 40 min after the injection of IPPA. Nine of the normal volunteers and 13 of the patients had a second examination performed at rest on another day. Using the limits of normal as 2 SD from the normal mean values, 27 of the 33 patients with coronary artery disease demonstrated abnormalities in either the initial distribution or the clearance of IPPA, or both. Nineteen of the 33 patients had a maximal variation of activity distribution of greater than or equal to 25% on the 9 min IPPA images. Twenty-two of the 33 patients had a maximal variation in IPPA washout greater than 17% and 17 had a washout rate less than or equal to 2%. There was good agreement between the location of significant coronary artery stenoses and abnormalities in the initial distribution and clearance of IPPA. The second hypothesis tested was that IPPA imaging is as or more sensitive and, therefore, complementary to thallium-201 imaging in the identification of exercise-induced ischemia in patients. Twenty-five of the 33 patients underwent both thallium-201 and IPPA tomographic imaging after symptom-limited maximal exercise testing. The amount of exercise performed by each patient during both studies was similar. Twenty

  3. Luminescent one- and two-dimensional extended structures and a loosely associated dimer based on platinum(II)-thallium(I) backbones.

    Science.gov (United States)

    Forniés, Juan; García, Ana; Lalinde, Elena; Moreno, M Teresa

    2008-05-05

    Neutralization reactions between (NBu4)2[ trans-Pt(C 6F5)2(CN)2] 1 and (NBu4)2[cis-Pt(C6F5)2(CN)2] 2 with TlPF 6 have been carried out, and the resulting structures of [trans,trans,trans-Tl2{Pt(C6F5)2(CN)2}.(CH3COCH3) ] n [4.(CH3COCH3)2] n and {Tl[Tl{cis-Pt(C6F5)2(CN)2}].(H2O)} n [5.(H2O)] n have been determined by X-ray crystallography. Remarkably, the change from trans to cis geometry on the platinum substrate causes a significant decrease in the Pt(II)...Tl(I) metallophilic interaction. Thus, the platinum center in the trans fragment easily connects with two Tl(I) ions forming a distorted pseudo-octahedron PtTl2, which generates a final two-dimensional layered structure by secondary additional intermolecular Tl(I)...N(CN) interactions. However, the [cis-Pt(C6F5)2(CN)2] (2-) fragment interacts strongly with just one Tl center leading to an extended helical [-Pt-Tl-Pt-Tl-] n(n-) chain. In this case, the second thallium center neutralizes the anionic chain mainly through Tl...N(CN) ( intra) and Tl...F(C 6F 5) (intra and inter)actions. The reaction of TlPF 6 with the monoanionic fragment (NBu4)[cis-Pt(C6F5)2(CN)(PPh2C[triple bond]CPh)] 3 yields the discrete associated dimer [Tl{cis-Pt(C6F5)2(CN)(PPh2C[triple bond]CPh)}] 2 [ 6] 2. Dimer [ 6] 2 could be described as two square pyramids with the thallium atoms in the apical positions, connected through Tl...N(cyano) interactions. The final heteropolynuclear Pt-Tl complexes, except 4 at room temperature, show bright emission in the solid state when irradiated with UV-vis radiation, in contrast to the precursors 1 and 3, which are not luminescent. This difference indicates that the emissions in 4- 6 are presumably related to the interaction between the metal centers. The Pt-Tl bonding interactions and, consequently, the emissive properties are lost in solution at room temperature, as shown by the conductivity and NMR measurements. However, variable-concentration luminescence measurements in glassy acetonitrile solutions

  4. Simultaneous dual myocardial imaging with iodine-123-[beta]-methyl iodophenyl-pentadecanoic acid (BMIPP) and thallium-201 in patients with coronary heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Tawarahara, Kei; Kurata, Chinori; Taguchi, Takahisa; Aoshima, Shigeyuki; Okayama, Kenichi; Kobayashi, Akira; Yamazaki, Noboru; Kaneko, Masao (Hamamatsu Univ. School of Medicine, Shizuoka (Japan))

    1994-02-01

    To assess the clinical value of simultaneous dual myocardial imaging with iodine-123-[beta]-methyl-iodophenyl-pentadecanoic acid ([sup 123]I-BMIPP) and thallium-201 ([sup 201]TL), myocardial imaging was performed at rest and during execise in seven patients with coronary heart disease. When [sup 123]I-BMIPP and [sup 201]Tl images were compared, the initial exercise and resting images agreed 87% and 64%, respectively. In the initial resting images, the regional uptake of [sup 123]I-BMIPP was frequently less than that of [sup 201]Tl. The incidence of exercise-induced reversible defects by [sup 201]Tl in the Tl>BMIPP regions was significantly higher than that in the Tl=BMIPP regions (57% vs 4%, p<0.01) and the incidence of coronary narrowing of more than 90% in the Tl>BMIPP regions was also significantly higher than that in the Tl=BMIPP regions (91% vs 38%, p<0.01). In addition, this disparity (Tl>BMIPP) was found more frequently in regions with abnormal wall motion than in regions with normal wall motion (hypokinetic regions; 68%, severe hypokinetic or akinetic regions; 50%, vs normokinetic regions; 4%, p<0.01). In contrast, the uptake of [sup 123]I-BMIPP correlated closely with that of [sup 201]Tl in normal myocardium and the uptake of both [sup 123]I-BMIPP and [sup 201]Tl was severely reduced in myocardium with severe ischemia during exercise and prior infarction. These results indicate that dual myocardial imaging with [sup 123]I-BMIPP and [sup 201]Tl may provide a unique means of identifying patients with metabolically disturbed myocardium, such as hibernating and stunned myocardium. (author).

  5. Imaging of brain tumors in AIDS patients by means of dual-isotope thallium-201 and technetium-99m sestamibi single-photon emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    De La Pena, R.C.; Ketonen, L.; Villanueva-Meyer, J. [Dept. of Radiology, Univ. of Texas, Galveston (United States)

    1998-10-01

    Our aim was to evaluate the use of dual-isotope thallium-201 (Tl) and technetium-99m sestamibi (sestamibi) simultaneous acquisition in brain single-photon emission tomography (SPET) for the differentiation between brain lymphoma and benign central nervous system (CNS) lesions in AIDS patients. Thirty-six consecutive patients with enhancing mass lesions on magnetic resonance (MR) imaging were included in the study. SPET of the brain was performed to obtain simultaneous Tl and sestamibi images. Regions-of-interest were drawn around the lesion and on the contralateral side to calculate uptake ratios. The final diagnosis was reached by pathologic findings in 17 patients and clinical and/or MR follow-up in 19 patients. Of the 36 patients, 11 had brain lymphoma, 1 glioblastoma multiforme, 15 toxoplasmosis and 9 other benign CNS lesions. Correlation between SPET and the final diagnosis revealed in 10 true-positive, 23 true-negative, 1 false-positive and 2 false-negative studies. All patients with toxoplasmosis had negative scans. A patient with a purulent infection had positive scans. Tl and sestamibi scans were concordant in every lesion. The same lesions that took up Tl were also visualized with sestamibi. However, sestamibi scans showed higher lesion-to-normal tissue uptake ratios (3.7{+-}1.8) compared with those of Tl (2.3{+-}0.8, P<0.002). Simultaneous acquisition of Tl and sestamibi can help differentiate CNS lymphoma from benign brain lesions in AIDS patients. (orig.) With 2 figs., 2 tabs., 34 refs.

  6. Technetium-99m pyrophosphate/thallium-201 dual-isotope SPECT imaging predicts reperfusion injury in patients with acute myocardial infarction after reperfusion

    Energy Technology Data Exchange (ETDEWEB)

    Akutsu, Yasushi; Kaneko, Kyouichi; Kodama, Yusuke; Li, Hui-Ling; Nishimura, Hideki; Hamazaki, Yuji; Kobayashi, Youichi [Showa University School of Medicine, Division of Cardiology, Department of Medicine, Tokyo (Japan); Suyama, Jumpei; Shinozuka, Akira; Gokan, Takehiko [Showa University School of Medicine, Department of Radiology, Tokyo (Japan)

    2009-02-15

    Microcirculatory failure after reperfusion is clinically indicated to cause reperfusion injury whereas excessive intracellular calcium ion overload is experimentally proved as a key mechanism of reperfusion injury. We hypothesized that technetium-99m ({sup 99m}Tc) pyrophosphate (Tc-PYP) uptake in injured but viable infarct-related myocardium with preserved myocardial perfusion after reperfusion estimated by thallium-201 ({sup 201}Tl) uptake would be associated with final functional recovery. Dual-isotope Tc-PYP/{sup 201}Tl single-photon emission computed tomography (SPECT) was performed 2 days after successful reperfusion therapy in patients with first acute myocardial infarction, and 50 patients (63 {+-} 13 years old, female 22%) with preserved {sup 201}Tl uptakes of {>=}50% in reperfused myocardium was followed for 1 month. Tc-PYP uptake was assessed as the heart-to-sternum (H/S) ratio. Two-dimensional echocardiography was also performed 2 days and 1 month after reperfusion to evaluate functional recovery. High Tc-PYP uptake, defined as the H/S ratio {>=}0.81, was predictive of chronic phase no functional recovery (73.7% in 14 of 19 patients with high uptake vs 16.1% in five of 31 patients without those, p < 0.0001). After adjustment for potential confounding variables, including electrocardiographic persistent ST segment elevation at 1 h after reperfusion, high Tc-PYP uptake remained independently predictive of no functional recovery with odds ratio of 8.7 (95% confidential interval = 2 to 38.7; p = 0.005). High Tc-PYP uptake in reperfused but viable infarct-related myocardium was a powerful predictor of no functional recovery, which may reflect excessive intracellular calcium ion overload caused by reperfusion injury. Tc-PYP/{sup 201}Tl dual-isotope SPECT imaging can provide prognostic information after reperfusion. (orig.)

  7. BaHg2Tl2. An unusual polar intermetallic phase with strong differentiation between the neighboring elements mercury and thallium.

    Science.gov (United States)

    Dai, Jing-Cao; Gupta, Shalabh; Gourdon, Olivier; Kim, Hyun-Jeong; Corbett, John D

    2009-06-24

    High yields of the novel BaHg(2)Tl(2) are achieved from reactions of the appropriate cast alloys at approximately 400 degrees C. (Isotypic SrHg(2)Tl(2) also exists.) The tetragonal barium structure (P4(2)/mnm, a = 10.606 A, c = 5.159 A) was refined from both single-crystal X-ray and neutron powder diffraction data in order to ensure the atom site assignments although distances and calculated atom site population also support the results. The Hg and Tl network atoms are distinctive in their functions and bonding. Parallel chains of Hg hexagons and of Tl tetrahedra along c are constructed from polyhedra that share opposed like edges, and these are in turn interconnected by Hg-Tl bonds. Overall, the number of Tl-Tl bonds per cell exceeds the Hg-Hg type by 20:12, but these are approximately 1:2 each in bonding according to their average -ICOHP values (related to overlap populations). Barium is bound within a close 15-atom polyhedron, 12 atoms of which are the more electronegative Hg. LMTO-ASA calculations show that scalar relativistic effects are particularly important for Hg 5d-6s mixing in Hg-Hg and Hg-Tl bonding, whereas relatively separate Tl 6s and 6p states are more important in Tl-Tl interactions. The 6p states of Hg and Tl and 5d of Ba define a dominant conduction band around E(F), and the phase is metallic and Pauli-like paramagnetic. The thallium characteristics here are close to those in numerous alkali-metal-Tl cluster systems. Other active metal-mercury phases that have been studied theoretically are all distinctly electron-richer and more reduced, and without appreciable net 5d, 6s contributions to Hg-Hg bonding.

  8. Relative value of thallium-201 and iodine-131 scans in the detection of recurrence or distant metastasis of well differentiated thyroid carcinoma.

    Science.gov (United States)

    Lin, J D; Kao, P F; Weng, H F; Lu, W T; Huang, M J

    1998-07-01

    Radioactive iodine (131I) has been found to be more sensitive and more specific than thallium-201 for the detection of distant metastases and thyroid remnants in the neck in cases of well-differentiated thyroid carcinoma. 201Tl has been deemed particularly useful in localizing metastases or recurrence in patients with a negative 131I scan and abnormal levels of serum thyroglobulin (Tg). This study aimed to: (1) determine the value of 201Tl imaging in localizing metastases or recurrence in patients with well-differentiated thyroid carcinoma, and (2) evaluate the false-positive and false-negative results of 131I and 201Tl scintigraphy. Sixty-two thyroid remnant ablated patients who underwent simultaneous postoperative 201Tl and 131I scans and and serum Tg determinations were evaluated. Fifty patients had papillary thyroid carcinomas and 12 had follicular thyroid carcinomas. 201Tl imaging was performed before the 131I studies. Of the 62 patients who underwent 201Tl imaging studies, 24 were found to have positive results, with local recurrence or distant metastases. Patients with positive results in the 201Tl imaging studies tended to be older, were mor often male, had higher Tg levels and had a higher recurrence rate. Of these 24 patients, ten had negative diagnostic or therapeutic 131I scans. Concurrently, serum Tg levels were less than 5 ng/ml in five of these ten patients. Three patients were deemed false positive by 201Tl scans; one had a parotid tumour, one a periodontal abscess and one lung metastasis. Among the 38 patients with negative 201Tl scans, 11 had positive findings on 131I scans. Three had distant metastases: two with lung metastases and one with bone metastases. Patients with false-positive results on 131I scans included those with biliary tract stones, ovarian cysts, and breast secretion. Of the 27 patients with negative 201Tl and 131I scans, 15 had elevated serum Tg levels. Among these, local recurrence followed by lung metastases was manifested in

  9. MRI and thallium features of pigmented villonodular synovitis and giant cell tumours of tendon sheaths: a retrospective single centre study of imaging and literature review.

    Science.gov (United States)

    Lynskey, Samuel J; Pianta, Marcus J

    2015-01-01

    The purpose of this study was to characterize the MRI and thallium-201 ((201)TI) scintigraphy attributes of pigmented villonodular synovitis (PVNS) and giant cell tumours of tendon sheaths (GCTTS). The epidemiology of these uncommon lesions was also assessed and less commonly encountered pathology reported on including multifocality, necrosis and concurrent malignancy. A retrospective single centre review of MRI and (201)TI scintigraphy findings for 83 surgically proven or biopsy-proven consecutive cases of PVNS was undertaken. Radiological findings including lesion size, (201)TI uptake (as a marker of metabolic activity), location, extent and patient demographics were correlated with biopsy and surgical specimen histology. Typical appearances are described, as well as less common imaging manifestations. The study period encompassed all patients presenting or referred to a tertiary bone and soft-tissue tumour referral centre with PVNS or GCTTS between 1 January 2007 and the 1 December 2013. Lesions occur most commonly around the knee joint in the fourth decade of life, with younger patients showing a tendency to occur in the hip. Features of PVNS and GTTS include bone erosion, ligamentous and cartilage replacement, muscle infiltration and multifocality. MR signal characteristics were variable but post-contrast enhancement was near-universal. 14 of 83 cases showed no uptake of (201)TI and revealed a statistically significant smaller average axial dimension of 19.8 mm than lesions displaying active (201)TI uptake of 36.4 mm, p = 0.016. Four lesions demonstrated central necrosis on gross histology, two of each from both the (201)TI-avid and (201)TI-non-avid groups. MR is the imaging modality of choice when considering the diagnosis of these uncommon tumours. (201)TI scintigraphy as a marker of metabolic activity further adds minimal value although small lesions can appear to lack (201)TI avidity. This article depicts typical imaging findings of PVNS/GCTTS and

  10. Relative value of thallium-201 and iodine-131 scans in the detection of recurrence or distant metastasis of well differentiated thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Lin Jen-Der; Weng Hsiao-Fen; Lu Wen-Tsoung [Division of Endocrinology and Metabolism, Chang Gung Memorial Hospital (Taiwan, Province of China); Kao Pan-Fu; Huang Miau-Ju [Department of Nuclear Medicine, Chang Gung Memorial Hospital, Taiwan (Taiwan, Province of China)

    1998-07-01

    Radioactive iodine ({sup 131}I) has been found to be more sensitive and more specific than thallium-201 for the detection of distant metastases and thyroid remnants in the neck in cases of well-differentiated thyroid carcinoma. {sup 201}Tl has been deemed particularly useful in localizing metastases or recurrence in patients with a negative {sup 131}I scan and abnormal levels of serum thyroglobulin (Tg). This study aimed to: (1) determine the value of {sup 201}Tl imaging in localizing metastases or recurrence in patients with well-differentiated thyroid carcinoma, and (2) evaluate the false-positive and false-negative results of {sup 131}I and {sup 201}Tl scintigraphy. Sixty-two thyroid remnant ablated patients who underwent simultaneous postoperative {sup 201}Tl and {sup 131}I scans and and serum Tg determinations were evaluated. Fifty patients had papillary thyroid carcinomas and 12 had follicular thyroid carcinomas. {sup 201}Tl imaging was performed before the {sup 131}I studies. Of the 62 patients who underwent {sup 201}Tl imaging studies, 24 were found to have positive results, with local recurrence or distant metastases. Patients with positive results in the {sup 201}Tl imaging studies tended to be older, were mor often male, had higher Tg levels and had a higher recurrence rate. Of these 24 patients, ten had negative diagnostic or therapeutic {sup 131}I scans. Concurrently, serum Tg levels were less than 5 ng/ml in five of these ten patients. Three patients were deemed false positive by {sup 201}Tl scans; one had a parotid tumour, one a periodontal abscess and one lung metastasis. Among the 38 patients with negative {sup 201}Tl scans, 11 had positive findings on {sup 131}I scans. Three had distant metastases: two with lung metastases and one with bone metastases. Patients with false-positive results on {sup 131}I scans included those with biliary tract stones, ovarian cysts, and breast secretion. Of the 27 patients with negative {sup 201}Tl and {sup 131}I

  11. Effects of adenosine and a selective A2A adenosine receptor agonist on hemodynamic and thallium-201 and technetium-99m-sestaMIBI biodistribution and kinetics.

    Science.gov (United States)

    Mekkaoui, Choukri; Jadbabaie, Farid; Dione, Donald P; Meoli, David F; Purushothaman, Kailasnath; Belardinelli, Luiz; Sinusas, Albert J

    2009-10-01

    The purpose of this study was to compare a selective A(2A) adenosine receptor agonist (regadenoson) with adenosine in clinically relevant canine models with regard to effects on hemodynamics and thallium-201 ((201)Tl) and technetium-99m ((99m)Tc)-sestaMIBI biodistribution and kinetics. The clinical application of vasodilator stress for perfusion imaging requires consideration of the effects of these vasodilating agents on systemic hemodynamics, coronary flow, and radiotracer uptake and clearance kinetics. Sequential imaging and arterial blood sampling was performed on control, anesthetized closed-chest canines (n = 7) to evaluate radiotracer biodistribution and kinetics after either a bolus administration of regadenoson (2.5 microg/kg) or 4.5-min infusion of adenosine (280 microg/kg). The effects of regadenoson on coronary flow and myocardial radiotracer uptake were then evaluated in an open-chest canine model of a critical stenosis (n = 7). Results from ex vivo single-photon emission computed tomography were compared with tissue well-counting. The use of regadenoson compared favorably with adenosine in regard to the duration and magnitude of the hemodynamic effects and the effect on (201)Tl and (99m)Tc-sestaMIBI biodistribution and kinetics. The arterial blood clearance half-time was significantly faster for (99m)Tc-sestaMIBI (regadenoson: 1.4 +/- 0.03 min; adenosine: 1.5 +/- 0.08 min) than for (201)Tl (regadenoson: 2.5 +/- 0.16 min, p adenosine: 2.7 +/- 0.04 min, p regadenoson stress was significantly greater than the relative perfusion defect with (99m)Tc-sestaMIBI (0.69 +/- 0.03%, p regadenoson produced a hyperemic response comparable to a standard infusion of adenosine. The biodistribution and clearance of both (201)Tl and (99m)Tc-sestaMIBI during regadenoson were similar to adenosine vasodilation. Ex vivo perfusion images under the most ideal conditions permitted detection of a critical stenosis, although (201)Tl offered significant advantages over (99m

  12. Comparison of 8-frame and 16-frame thallium-201 gated myocardial perfusion SPECT for determining left ventricular systolic and diastolic parameters.

    Science.gov (United States)

    Kurisu, Satoshi; Sumimoto, Yoji; Ikenaga, Hiroki; Watanabe, Noriaki; Ishibashi, Ken; Dohi, Yoshihiro; Fukuda, Yukihiro; Kihara, Yasuki

    2017-07-01

    The myocardial perfusion single photon emission computed tomography synchronized with the electrocardiogram (gated SPECT) has been widely used for the assessment of left ventricular (LV) systolic and diastolic functions using Quantitative gated SPECT. The aim of this study was to compare the effects of 8-frame and 16-frame thallium-201 (Tl-201) gated SPECT for determining LV systolic and diastolic parameters. The study population included 42 patients with suspected coronary artery disease who underwent gated SPECT by clinical indication. LV systolic and diastolic parameters were assessed on 8-frame and 16-frame gated SPECT. There were good correlations in end-diastolic volume (r = 0.99, p < 0.001), end-systolic volume (ESV) (r = 0.97, p < 0.001) and ejection fraction (EF) (r = 0.95, p < 0.001) between 8-frame and 16-frame gated SPECT. Bland-Altman plot showed a significant negative slope of -0.08 in EDV indicating a larger difference for larger EDV. Eight-frame gated SPECT overestimated ESV by 2.3 ml, and underestimated EF by -4.2% than 16-frame gated SPECT. There were good correlations in peak filling rate (PFR) (r = 0.87, p < 0.001), one third mean filling rate (r = 0.87, p < 0.001) and time to PFR (r = 0.61, p < 0.001) between 8-frame and 16-frame gated SPECT. Eight-frame gated SPECT underestimated PFR by -0.22 than 16-frame gated SPECT. Eight-frame gated SPECT estimated as much MFR/3 and TPFR as 16-frame gated SPECT. According to the data, the study suggested that 8-frame Tl-201 gated SPECT could underestimate systolic and/or diastolic parameter when compared with 16-frame gated SPECT.

  13. Yield and excitation function measurements of some nuclear reactions on natural thallium induced by protons leading to the production of medical radioisotopes {sup 201}Tl and {sup 203}Pb

    Energy Technology Data Exchange (ETDEWEB)

    Al-Saleh, F.S.; Al-Harbi, A.A. [Girls College of Education, Riyadh (Saudi Arabia). Physics Dept.; Azzam, A. [Nuclear Research Center, Cairo (Egypt). Nuclear Physics Dept.

    2007-07-01

    Excitation functions for {sup 201}Pb, {sup 202m}Pb, {sup 203}Pb and {sup 204m}Pb radionuclides which are formed via proton induced reactions with natural thallium target have been measured from their respective threshold (E{sub thr}) to 27.5 MeV using activation technique. Natural copper foils were used to monitor the cyclotron beam. The integral yields (MBq/{mu}A h) of the produced radionuclides were calculated from the measured excitation functions. The optimum proton energy range for the production of {sup 203}Pb with low amount of impurities is (16-10 MeV) after 5 h of EOB. The experimental cross-sections for {sup nat}Tl(p,xn) reactions were compared with the cross-sections recommended by the IAEA and with earlier published data when it was possible. (orig.)

  14. Calcium Carbonate

    Science.gov (United States)

    Calcium carbonate is a dietary supplement used when the amount of calcium taken in the diet is not ... for healthy bones, muscles, nervous system, and heart. Calcium carbonate also is used as an antacid to relieve ...

  15. Carbon-On-Carbon Manufacturing

    Science.gov (United States)

    Mungas, Gregory S. (Inventor); Buchanan, Larry (Inventor); Banzon, Jr., Jose T. (Inventor)

    2017-01-01

    The presently disclosed technology relates to carbon-on-carbon (C/C) manufacturing techniques and the resulting C/C products. One aspect of the manufacturing techniques disclosed herein utilizes two distinct curing operations that occur at different times and/or using different temperatures. The resulting C/C products are substantially non-porous, even though the curing operation(s) substantially gasify a liquid carbon-entrained filler material that saturates a carbon fabric that makes up the C/C products.

  16. Porous carbons

    Indian Academy of Sciences (India)

    Carbon in dense as well as porous solid form is used in a variety of applications. Activated porous carbons are made through pyrolysis and activation of carbonaceous natural as well as synthetic precursors. Pyrolysed woods replicate the structure of original wood but as such possess very low surface areas and poor ...

  17. Thermodynamic Properties of Aqueous Carbonate Species and Solid Carbonate Phases of Selected Trace Elements pertinent to Drinking Water Standards of the U.S. Environmental Protection Agency

    Energy Technology Data Exchange (ETDEWEB)

    Apps, John A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wilkin, Richard T. [US Environmental Protection Agency (EPA), Cincinnati, OH (United States)

    2015-09-30

    This report contains a series of tables summarizing the thermodynamic properties of aqueous carbonate complexes and solid carbonate phases of the following elements: arsenic (As), barium (Ba), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), manganese (Mn), mercury (Hg), nickel (Ni) thallium (Tl), uranium (U) and zinc (Zn). Most of these elements are potentially hazardous as defined by extant primary drinking water standards of the United States Environmental Protection Agency (EPA). The remainder are not considered hazardous, but are either listed by EPA under secondary standards, or because they can adversely affect drinking water quality. Additional tables are included giving the thermodynamic properties for carbonates of the alkali metal and alkali earth elements, sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), and strontium (Sr), because of their value in developing correlative models to estimate the thermodynamic properties of carbonate minerals for which no such data currently exist. The purpose in creating the tables in this report is to provide future investigators with a convenient source for selecting and tracing the sources of thermodynamic data of the above listed elements for use in modeling their geochemical behavior in “underground sources of drinking water” (USDW). The incentive for doing so lies with a heightened concern over the potential consequences of the proposed capture and storage of carbon dioxide (CO2) generated by fossil fuel fired power plants in deep subsurface reservoirs. If CO2 were to leak from such reservoirs, it could migrate upward and contaminate USDWs with undesirable, but undetermined, consequences to water quality. The EPA, Office of Research and Development, through an Interagency Agreement with the U.S. Department of Energy at the Lawrence Berkeley National Laboratory, funded the preparation of this report.

  18. Carbon Stars

    Indian Academy of Sciences (India)

    Abstract. In this paper, the present state of knowledge of the carbon stars is discussed. Particular attention is given to issues of classification, evolution, variability, populations in our own and other galaxies, and circumstellar material.

  19. Developments in carbon materials

    Science.gov (United States)

    Burchell, Timothy D.

    1994-01-01

    The following carbon-based materials are reviewed and their applications discussed: fullerenes; graphite (synthetic and manufactured); activated carbon fibers; and carbon-carbon composites. Carbon R&D activities at ORNL are emphasized.

  20. Significance of exercise-induced ST segment depression in patients with myocardial infarction involving the left circumflex artery. Evaluation by exercise thallium-201 myocardial single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Koitabashi, Norimichi; Toyama, Takuji; Hoshizaki, Hiroshi [Gunma Prefectural Cardiovascular Center, Maebashi (Japan)] [and others

    2000-04-01

    The significance of exercise-induced ST segment depression in patients with left circumflex artery involvement was investigated by comparing exercise electrocardiography with exercise thallium-201 single photon emission computed tomography (Tl-SPECT) and the wall motion estimated by left ventriculography. Tl-SPECT and exercise electrocardiography were simultaneously performed in 51 patients with left circumflex artery involvement (angina pectoris 30, myocardial infarction 21). In patients with myocardial infarction, exercise-induced ST depression was frequently found in the V{sub 2}, V{sub 3} and V{sub 4} leads. In patients with angina pectoris, ST depression was frequently found in the II, III, aV{sub F}, V{sub 5} and V{sub 6} leads. There was no obvious difference in the leads of ST depression in patients with myocardial infarction with ischemia and without ischemia on Tl-SPECT images. In patients with myocardial infarction, the lateral wall motion of the infarcted area evaluated by left ventriculography was more significantly impaired in the patients with ST depression than without ST depression (p<0.01). Exercise-induced ST depression in the precordial leads possibly reflects wall motion abnormality rather than ischemia in the lateral infarcted myocardium. (author)

  1. Infiltrated carbon foam composites

    Science.gov (United States)

    Lucas, Rick D. (Inventor); Danford, Harry E. (Inventor); Plucinski, Janusz W. (Inventor); Merriman, Douglas J. (Inventor); Blacker, Jesse M. (Inventor)

    2012-01-01

    An infiltrated carbon foam composite and method for making the composite is described. The infiltrated carbon foam composite may include a carbonized carbon aerogel in cells of a carbon foam body and a resin is infiltrated into the carbon foam body filling the cells of the carbon foam body and spaces around the carbonized carbon aerogel. The infiltrated carbon foam composites may be useful for mid-density ablative thermal protection systems.

  2. Carbon classified?

    DEFF Research Database (Denmark)

    Lippert, Ingmar

    2012-01-01

    . Using an actor- network theory (ANT) framework, the aim is to investigate the actors who bring together the elements needed to classify their carbon emission sources and unpack the heterogeneous relations drawn on. Based on an ethnographic study of corporate agents of ecological modernisation over...... and corporations construing themselves as able and suitable to manage their emissions, and, additionally, given that the construction of carbon emissions has performative consequences, the underlying practices need to be declassified, i.e. opened for public scrutiny. Hence the paper concludes by arguing...

  3. Carbon-carbon - An overview

    Science.gov (United States)

    Buckley, John D.

    1988-01-01

    In nonoxidizing high-temperature environments, carbon-carbon composites retain room temperature properties to more than 2225 C; in oxidizing environments, the variety of coatings thus far developed limits maximum operating temperatures to about 1600 C. The high thermal conductivity and low thermal expansion of these composites renders them ideal for applications encountering thermal shocks. In addition, the variety of fibers, weave patterns, and layup procedures that can be used for the composites allows mechanical properties to be carefully tailored over a wide range to fit the application in question.

  4. Diagnostic value of thallium-201 myocardial perfusion IQ-SPECT without and with computed tomography-based attenuation correction to predict clinically significant and insignificant fractional flow reserve: A single-center prospective study.

    Science.gov (United States)

    Tanaka, Haruki; Takahashi, Teruyuki; Ohashi, Norihiko; Tanaka, Koichi; Okada, Takenori; Kihara, Yasuki

    2017-12-01

    The aim of this study was to clarify the predictive value of fractional flow reserve (FFR) determined by myocardial perfusion imaging (MPI) using thallium (Tl)-201 IQ-SPECT without and with computed tomography-based attenuation correction (CT-AC) for patients with stable coronary artery disease (CAD).We assessed 212 angiographically identified diseased vessels using adenosine-stress Tl-201 MPI-IQ-SPECT/CT in 84 consecutive, prospectively identified patients with stable CAD. We compared the FFR in 136 of the 212 diseased vessels using visual semiquantitative interpretations of corresponding territories on MPI-IQ-SPECT images without and with CT-AC.FFR inversely correlated most accurately with regional summed difference scores (rSDS) in images without and with CT-AC (r = -0.584 and r = -0.568, respectively, both P < .001). Receiver-operating characteristics analyses using rSDS revealed an optimal FFR cut-off of <0.80 without and with CT-AC. Although the diagnostic accuracy of FFR <0.80 did not significantly differ, FFR ≥0.82 was significantly more accurate with, than without CT-AC. Regions with rSDS ≥2 without or with CT-AC predicted FFR <0.80, and those with rSDS ≤1 without and with CT-AC predicted FFR ≥0.81, with 73% and 83% sensitivity, 84% and 67% specificity, and 79% and 75% accuracy, respectively.Although limited by the sample size and the single-center design, these findings showed that the IQ-SPECT system can predict FFR at an optimal cut-off of <0.80, and we propose a novel application of CT-AC to MPI-IQ-SPECT for predicting clinically significant and insignificant FFR even in nonobese patients. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

  5. Dual myocardial single photon emission computed tomography (SPECT) using thallium-201 and I-123-{beta}-methyl-i-pentadecanoic acid in patients with Duchenne's progressive muscular dystrophy

    Energy Technology Data Exchange (ETDEWEB)

    Shimoyama, Katsuya [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine

    1999-10-01

    Dual single photon emission computed tomography (SPECT) was performed in 31 patients with Duchenne's progressive muscular dystrophy (DMD) using {sup 123}I-{beta}-methyl pentadecanoic acid (BMIPP) for myocardial fatty acid metabolism and {sup 201}thallium (Tl)-chloride for myocardial perfusion. The left ventricle was divided into 9 segments, and accumulation of the radiotracers was assessed visually for each segment to calculate defect score for each tracer. There was some degree of decrease in myocardial accumulation of both tracers in all DMD patients. Reduced accumulation was most common at the apex (BMIPP: 67%, Tl: 63%), followed by the posterior wall, lateral wall, and anterior wall. On the other hand, reduced accumulation was less common at the septum. BMIPP showed a higher accumulation than Tl in all segments but the septum. When BMIPP defect score was larger than Tl defect score, BMIPP defect score tended to increase during 4 years follow-up (p<0.042). However, when Tl defect score was larger than BMIPP defect score, an increase in Tl defect score was slight. A significant negative correlation was found between the sum of the BMIPP and Tl defect scores and the left ventricular ejection fraction (LVEF) (r=0.66, p<0.0001). According to the histo-pathological study of two autopsied hearts, severe myocardial fibrosis was seen in segments with fixed perfusion defect. In addition, the mismatched segments of BMIPP defect score > Tl defect score revealed a slight fibrosis or normal myocardium. It can be concluded that the dual SPECT myocardial scintigraphy using BMIPP and Tl provides accurate information about disease progression of the heart in patients with DMD by detecting abnormalities of the myocardial metabolism of each substance, thereby enabling the assessment of left ventricular function. (author)

  6. Carbon Based Refractories

    National Research Council Canada - National Science Library

    EWAIS, Emad Mohamed M

    2004-01-01

    .... They are classified into two groups; carbon/bricks/blocks and carbon containing materials. Carbon containing materials are further classified into carbon containing basic refractories and non-basic refractories...

  7. Carbon nanotubes

    OpenAIRE

    SLOBODAN N. MARINKOVIC

    2008-01-01

    Nanotubes, the last in the focus of scientists in a series of “all carbon” materials discovered over the last several decades are the most interesting and have the greatest potential. This review aims at presenting in a concise manner the considerable amount of knowledge accumulated since the discovery of this amazing form of solid carbon, particularly during the last 15 years. The topics include methods of synthesis, mathematical description, characterization by Raman spectroscopy, most impo...

  8. Interaction of the thallium cation with 1,3-alternate-25,27-bis(1-octyloxy)calix[4]arene-crown-6: Experimental and theoretical study

    Science.gov (United States)

    Makrlík, Emanuel; Dybal, Jiří; Vaňura, Petr

    2013-06-01

    From extraction experiments and γ-activity measurements, the extraction constant corresponding to the equilibrium Tl+ (aq) + 1·Cs+ (nb) ⇔ 1·Tl+ (nb) + Cs+ (aq) taking place in the two-phase water-nitrobenzene system (1 = 1,3-alternate-25,27-bis(1-octyloxy)calix[4]arene-crown-6; aq = aqueous phase, nb = nitrobenzene phase) was evaluated as log Kex (Tl+, 1·Cs+) = -2.1 ± 0.1. Further, the stability constant of the 1·Tl+ complex in nitrobenzene saturated with water was calculated for a temperature of 25 °C: log βnb(1·Tl+) = 11.6 ± 0.2. Finally, by using quantum mechanical DFT calculations, the most probable structures A and B of the cationic complex species 1·Tl+, which are obviously in a dynamic equilibrium, were indicated. In both of these structures of the resulting 1·Tl+ complex, the "central" cation Tl+ is bound by eight strong bond interactions to six oxygen atoms from the 18-crown-6 moiety and to two carbons of the respective two benzene rings of the parent ligand 1 via cation-π interaction.

  9. Calix[4]arene-(2,3-naphthylene-crown-6,crown-6) as an extraordinarily efficient macrocyclic receptor for the univalent thallium cation

    Science.gov (United States)

    Makrlík, Emanuel; Böhm, Stanislav; Kvíčalová, Magdalena; Vaňura, Petr; Asfari, Zouhair

    2015-11-01

    On the basis of extraction experiments and γ-activity measurements, the extraction constant corresponding to the equilibrium Tl+ (aq) + 1.Cs+ (nb) ? 1.Tl+ (nb) + Cs+ (aq) taking place in the two-phase water-nitrobenzene system (1 = calix[4]arene-(2,3-naphthylene-crown-6,crown-6); aq = aqueous phase, nb = nitrobenzene phase) was determined as log Kex(Tl+,1.Cs+) = 0.3 ± 0.1. Further, the extremely high stability constant of the 1.Tl+ complex in nitrobenzene saturated with water was calculated for a temperature of 25 °C: log βnb(1.Tl+) = 10.0 ± 0.2. Finally, applying quantum mechanical calculations, the most probable structure of the cationic complex species 1.Tl+ was derived. In the resulting complex, the 'central' cation Tl+ is bound by eight strong bonds to six oxygen atoms of the crown-6 moiety and to two carbons from the respective two benzene rings of the parent ligand 1 via cation-π interaction. The interaction energy, E(int), of the considered 1.Tl+ complex was found to be -305.7 kJ/mol, also confirming the formation of this cationic species.

  10. Evaluation of myocardial flow reserve using pharmacological stress thallium-201 single-photon emission computed tomography: is there a difference between total arterial off-pump coronary artery bypass grafting and conventional coronary artery bypass grafting?

    Science.gov (United States)

    Lee, Jae Won; Ryu, Sang Wan; Song, Hyun; Kim, Kyung Sun; Yang, Yu Jung; Moon, Dae Hyeuk

    2004-01-01

    The advantage of total arterial off-pump coronary bypass grafting (OPCAB) over conventional onpump coronary artery bypass grafting with 1 internal thoracic artery and veins (CCAB) in terms of myocardial flow reserve has not been studied. We studied these procedures using thallium- 201 perfusion single-photon emission computed tomography (Tl-201 perfusion SPECT). Between 1997 and 2001, 152 patients were recruited from our database (OPCAB, n = 100; CCAB, n = 52). All patients underwent pharmacological stress Tl-201 perfusion SPECT 3 to 12 months after bypass surgery. Myocardial perfusion was analyzed semiquantitatively with a 5-point scoring system in a 20-segment model (0, normal, to 4, absence of uptake). Summed stress (SSS), rest (SRS), and difference score (SDS) of the entire myocardium as well as average scores (ASS, ARS, ADS) of individual walls (anterior, septal, lateral, and inferior) were compared by Student t test as well as by repeated-measures analysis of variance with Bonferroni correction. The SSS, SRS, and SDS of OPCAB versus those of CCAB were 6.86 +/- 0.72 versus 7.17 +/- 0.92, 3.95 +/- 0.57 versus 3.75 +/- 0.73, and 2.91 +/- 0.47 versus 3.42 +/- 0.74 (P > .05). However, the lateral wall showed lower scores in OPCAB (ASS, 0.18 versus 0.41, P = .015; ARS, 0.12 versus 0.20, P = .168; ADS, 0.06 versus 0.21, P = .031). The septal wall had higher scores in OPCAB (ASS, 0.33 versus 0.12, P = .003; ARS, 0.18 versus 0.07, P = .037; ADS, 0.14 versus 0.04, P = .030). The anterior and inferior walls were not different between the 2 groups. OPCAB led to results similar to those of CCAB. The better results in the lateral wall have been the effect of grafting radial artery rather than vein. The similarity in myocardial reserve in the inferior wall between the 2 groups needs further study. There was no deleterious effect of off-pump as opposed to on-pump CAB.

  11. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Education Centers Carbon Monoxide Information Center Carbon Monoxide Information Center En Español The Invisible Killer Carbon monoxide, ... Install one and check its batteries regularly. View Information About CO Alarms Other CO Topics Safety Tips ...

  12. Net Ecosystem Carbon Flux

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Net Ecosystem Carbon Flux is defined as the year-over-year change in Total Ecosystem Carbon Stock, or the net rate of carbon exchange between an ecosystem and the...

  13. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Education Safety Education Centers Carbon Monoxide Information Center Carbon Monoxide Information Center En Español The Invisible Killer Carbon monoxide, also known as CO, is called the "Invisible ...

  14. Carbon-carbon grid for ion engines

    Science.gov (United States)

    Garner, Charles E. (Inventor)

    1995-01-01

    A method and apparatus of manufacturing a grid member for use in an ion discharge apparatus provides a woven carbon fiber in a matrix of carbon. The carbon fibers are orientated to provide a negatibe coefficient of thermal expansion for at least a portion of the grid member's operative range of use.

  15. Carbon dioxide sequestration by mineral carbonation

    NARCIS (Netherlands)

    Huijgen, W.J.J.

    2007-01-01

    The increasing atmospheric carbon dioxide (CO2) concentration, mainly caused by fossil fuel combustion, has lead to concerns about global warming. A possible technology that can contribute to the reduction of carbon dioxide emissions is CO2 sequestration by mineral carbonation. The basic concept

  16. Composite carbon foam electrode

    Science.gov (United States)

    Mayer, S.T.; Pekala, R.W.; Kaschmitter, J.L.

    1997-05-06

    Carbon aerogels used as a binder for granulated materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy. 1 fig.

  17. Carbon Nanomembranes

    Science.gov (United States)

    Angelova, Polina; Gölzhäuser, Armin

    2017-03-01

    This chapter describes the formation and properties of one nanometer thick carbon nanomembranes (CNMs), made by electron induced cross-linking of aromatic self-assembled monolayers (SAMs). The cross-linked SAMs are robust enough to be released from the surface and placed on solid support or over holes as free-standing membranes. Annealing at 1000K transforms CNMs into graphene accompanied by a change of mechanical stiffness and electrical resistance. The developed fabrication approach is scalable and provides molecular level control over thickness and homogeneity of the produced CNMs. The mechanisms of electron-induced cross-linking process are discussed in details. A variety of polyaromatic thiols: oligophenyls as well as small and extended condensed polycyclic hydrocarbons have been successfully employed, demonstrating that the structural and functional properties of the resulting nanomembranes are strongly determined by the structure of molecular monolayers. The mechanical properties of CNMs (Young's modulus, tensile strength and prestress) are characterized by bulge testing. The interpretation of the bulge test data relates the Young's modulus to the properties of single molecules and to the structure of the pristine SAMs. The gas transport through the CNM is measured onto polydimethylsiloxane (PDMS) - thin film composite membrane. The established relationship of permeance and molecular size determines the molecular sieving mechanism of permeation through this ultrathin sheet.

  18. Mutagenicity of carbon nanomaterials.

    Science.gov (United States)

    Wallin, Håkan; Jacobsen, Nicklas Raun; White, Paul A; Gingerich, John; Møller, Peter; Loft, Steffen; Vogel, Ulla

    2011-02-01

    Carbon nanomaterials such carbon nanotubes, graphene and fullerenes are some the most promising nanomaterials. Although carbon nanomaterials have been reported to possess genotoxic potential, it is imperitive to analyse the data on the genotoxicity of carbon nanomaterials in vivo and in vitro and check the validity and predictability of different assays.

  19. Mutagenicity of carbon nanomaterials

    DEFF Research Database (Denmark)

    Wallin, Håkan; Jacobsen, Nicklas Raun; White, Paul A

    2011-01-01

    Carbon nanomaterials such carbon nanotubes, graphene and fullerenes are some the most promising nanomaterials. Although carbon nanomaterials have been reported to possess genotoxic potential, it is imperitive to analyse the data on the genotoxicity of carbon nanomaterials in vivo and in vitro...

  20. Permafrost-carbon complexities

    NARCIS (Netherlands)

    Vonk, J.E.; Gustafsson, Ö.

    2013-01-01

    The thawing and decomposition of carbon stored in permafrost generates greenhouse gases that could further intensify global warming. Currently, most of the thawed carbon is assumed to be converted to greenhouse gases, such as carbon dioxide and methane, and carbon decomposition is thought

  1. Carbon nanotube composite materials

    Science.gov (United States)

    O'Bryan, Gregory; Skinner, Jack L; Vance, Andrew; Yang, Elaine Lai; Zifer, Thomas

    2015-03-24

    A material consisting essentially of a vinyl thermoplastic polymer, un-functionalized carbon nanotubes and hydroxylated carbon nanotubes dissolved in a solvent. Un-functionalized carbon nanotube concentrations up to 30 wt % and hydroxylated carbon nanotube concentrations up to 40 wt % can be used with even small concentrations of each (less than 2 wt %) useful in producing enhanced conductivity properties of formed thin films.

  2. Carbon repression in Aspergilli.

    NARCIS (Netherlands)

    Ruijter, G.J.G.; Visser, J.

    1997-01-01

    Many microorganisms prefer easily metabolizable carbon sources over alternative, less readily metabolized carbon sources. One of the mechanisms to achieve this is repression of the synthesis of enzymes related to catabolism of the alternative carbon sources, i.e. carbon repression. It is now clear

  3. Pyrolyzed thin film carbon

    Science.gov (United States)

    Tai, Yu-Chong (Inventor); Liger, Matthieu (Inventor); Harder, Theodore (Inventor); Konishi, Satoshi (Inventor); Miserendino, Scott (Inventor)

    2010-01-01

    A method of making carbon thin films comprises depositing a catalyst on a substrate, depositing a hydrocarbon in contact with the catalyst and pyrolyzing the hydrocarbon. A method of controlling a carbon thin film density comprises etching a cavity into a substrate, depositing a hydrocarbon into the cavity, and pyrolyzing the hydrocarbon while in the cavity to form a carbon thin film. Controlling a carbon thin film density is achieved by changing the volume of the cavity. Methods of making carbon containing patterned structures are also provided. Carbon thin films and carbon containing patterned structures can be used in NEMS, MEMS, liquid chromatography, and sensor devices.

  4. Carbon-based spintronics

    Science.gov (United States)

    Chen, Peng; Zhang, GuangYu

    2013-01-01

    Carbon-based spintronics refers mainly to the spin injection and transport in carbon materials including carbon nanotubes, graphene, fullerene, and organic materials. In the last decade, extraordinary development has been achieved for carbon-based spintronics, and the spin transport has been studied in both local and nonlocal spin valve devices. A series of theoretical and experimental studies have been done to reveal the spin relaxation mechanisms and spin transport properties in carbon materials, mostly for graphene and carbon nanotubes. In this article, we provide a brief review on spin injection and transport in graphene, carbon nanotubes, fullerene and organic thin films.

  5. Wood - a carbon depot

    OpenAIRE

    Lipušček, Igor; Tišler, Vesna

    2003-01-01

    The article examines the global movement of carbon dioxide, the most important greenhouse gas due to its large quantities. We studied the carbon cycle with possibilities of its extension, and analysed the mechanisms that remove carbon dioxide from the atmosphere and bind it into solid substances for a longer period of time. The focus was on carbon dioxide sink into biomass and carbon deposit in wood. On the basis of wood component data and chemical analysis of the components, we calculated th...

  6. Characteristics of photoconductivity in thallium monosulfide single ...

    Indian Academy of Sciences (India)

    Pramana – Journal of Physics. Current Issue : Vol. 90, Issue 1 · Current Issue Volume 90 | Issue 1. January 2018. Home · Volumes & Issues · Special Issues · Forthcoming Articles · Search · Editorial Board · Information for Authors · Subscription ...

  7. Substantial global carbon uptake by cement carbonation

    Science.gov (United States)

    Xi, Fengming; Davis, Steven J.; Ciais, Philippe; Crawford-Brown, Douglas; Guan, Dabo; Pade, Claus; Shi, Tiemao; Syddall, Mark; Lv, Jie; Ji, Lanzhu; Bing, Longfei; Wang, Jiaoyue; Wei, Wei; Yang, Keun-Hyeok; Lagerblad, Björn; Galan, Isabel; Andrade, Carmen; Zhang, Ying; Liu, Zhu

    2016-12-01

    Calcination of carbonate rocks during the manufacture of cement produced 5% of global CO2 emissions from all industrial process and fossil-fuel combustion in 2013. Considerable attention has been paid to quantifying these industrial process emissions from cement production, but the natural reversal of the process--carbonation--has received little attention in carbon cycle studies. Here, we use new and existing data on cement materials during cement service life, demolition, and secondary use of concrete waste to estimate regional and global CO2 uptake between 1930 and 2013 using an analytical model describing carbonation chemistry. We find that carbonation of cement materials over their life cycle represents a large and growing net sink of CO2, increasing from 0.10 GtC yr-1 in 1998 to 0.25 GtC yr-1 in 2013. In total, we estimate that a cumulative amount of 4.5 GtC has been sequestered in carbonating cement materials from 1930 to 2013, offsetting 43% of the CO2 emissions from production of cement over the same period, not including emissions associated with fossil use during cement production. We conclude that carbonation of cement products represents a substantial carbon sink that is not currently considered in emissions inventories.

  8. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Non-Fire Carbon Monoxide Deaths Associated with the Use of Consumer Products 2012 Annual Estimates OCTOBER 13, ... Non-Fire Carbon Monoxide Deaths Associated with the Use of Consumer Products 2011 Annual Estimates View All ...

  9. Trading forest carbon - OSU

    Science.gov (United States)

    Issues associate with trading carbon sequestered in forests are discussed. Scientific uncertainties associated with carbon measurement are discussed with respect to proposed accounting procedures. Major issues include: (1) Establishing baselines. (2) Determining additivity from f...

  10. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Center Carbon Monoxide Information Center En Español The Invisible Killer Carbon monoxide, also known as CO, is called the "Invisible Killer" because it's a colorless, odorless, poisonous gas. ...

  11. Carbon Materials Research

    National Research Council Canada - National Science Library

    Hoffman, Wesley P

    2005-01-01

    Carbon-carbon composites have been used by the Air Force and others for over 25 years in a variety of thermostructural applications including rocket propulsion, re-entry, hypersonics and aircraft brakes...

  12. Preparing to Capture Carbon

    National Research Council Canada - National Science Library

    Daniel P. Schrag

    2007-01-01

    .... Scientific and economic challenges still exist, but none are serious enough to suggest that carbon capture and storage will not work at the scale required to offset trillions of tons of carbon...

  13. Carbon nanotube nanoelectrode arrays

    Science.gov (United States)

    Ren, Zhifeng; Lin, Yuehe; Yantasee, Wassana; Liu, Guodong; Lu, Fang; Tu, Yi

    2008-11-18

    The present invention relates to microelectode arrays (MEAs), and more particularly to carbon nanotube nanoelectrode arrays (CNT-NEAs) for chemical and biological sensing, and methods of use. A nanoelectrode array includes a carbon nanotube material comprising an array of substantially linear carbon nanotubes each having a proximal end and a distal end, the proximal end of the carbon nanotubes are attached to a catalyst substrate material so as to form the array with a pre-determined site density, wherein the carbon nanotubes are aligned with respect to one another within the array; an electrically insulating layer on the surface of the carbon nanotube material, whereby the distal end of the carbon nanotubes extend beyond the electrically insulating layer; a second adhesive electrically insulating layer on the surface of the electrically insulating layer, whereby the distal end of the carbon nanotubes extend beyond the second adhesive electrically insulating layer; and a metal wire attached to the catalyst substrate material.

  14. Biomass Carbon Stock

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Biomass carbon includes carbon stored in above- and below-ground live plant components (such as leaf, branch, stem and root) as well as in standing and down dead...

  15. Soil Organic Carbon Stock

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Soil organic carbon (SOC) is the carbon held within soil organic constituents (i.e., products produced as dead plants and animals decompose and the soil microbial...

  16. Calcium carbonate overdose

    Science.gov (United States)

    Tums overdose; Calcium overdose ... Calcium carbonate can be dangerous in large amounts. ... Some products that contain calcium carbonate are certain: ... and mineral supplements Other products may also contain calcium ...

  17. Carbon Goes To…

    Science.gov (United States)

    Savasci, Funda

    2014-01-01

    The purposes of this activity are to help middle school students understand the carbon cycle and realize how human activities affect the carbon cycle. This activity consists of two parts. The first part of the activity focuses on the carbon cycle, especially before the Industrial Revolution, while the second part of the activity focuses on how…

  18. TWIN CARBON ARC TORCH

    African Journals Online (AJOL)

    its predominate applications in heating, brazing, and welding have been supplanted by the highly developed oxyacetylene torch. As seen in Fig. l, the twin carbon arc torch (henceforth referred to in this article as simply the carbon-arc torch) consists of a hand held apparatus made of two ('twin') carbon or graphite electrodes ...

  19. Carbon nanotube quantum dots

    NARCIS (Netherlands)

    Sapmaz, S.

    2006-01-01

    Low temperature electron transport measurements on individual single wall carbon nanotubes are described in this thesis. Carbon nanotubes are small hollow cylinders made entirely out of carbon atoms. At low temperatures (below ~10 K) finite length nanotubes form quantum dots. Because of its small

  20. Protolytic carbon film technology

    Energy Technology Data Exchange (ETDEWEB)

    Renschler, C.L.; White, C.A.

    1996-04-01

    This paper presents a technique for the deposition of polyacrylonitrile (PAN) on virtually any surface allowing carbon film formation with only the caveat that the substrate must withstand carbonization temperatures of at least 600 degrees centigrade. The influence of processing conditions upon the structure and properties of the carbonized film is discussed. Electrical conductivity, microstructure, and morphology control are also described.

  1. Carbon/Carbon Pistons for Internal Combustion Engines

    Science.gov (United States)

    Taylor, A. H.

    1986-01-01

    Carbon/carbon piston performs same function as aluminum pistons in reciprocating internal combustion engines while reducing weight and increasing mechanical and thermal efficiencies of engine. Carbon/carbon piston concept features low piston-to-cylinder wall clearance - so low piston rings and skirts unnecessary. Advantages possible by negligible coefficient of thermal expansion of carbon/carbon.

  2. Latest Permian carbonate carbon isotope variability traces heterogeneous organic carbon accumulation and authigenic carbonate formation

    Directory of Open Access Journals (Sweden)

    M. Schobben

    2017-11-01

    Full Text Available Bulk-carbonate carbon isotope ratios are a widely applied proxy for investigating the ancient biogeochemical carbon cycle. Temporal carbon isotope trends serve as a prime stratigraphic tool, with the inherent assumption that bulk micritic carbonate rock is a faithful geochemical recorder of the isotopic composition of seawater dissolved inorganic carbon. However, bulk-carbonate rock is also prone to incorporate diagenetic signals. The aim of the present study is to disentangle primary trends from diagenetic signals in carbon isotope records which traverse the Permian–Triassic boundary in the marine carbonate-bearing sequences of Iran and South China. By pooling newly produced and published carbon isotope data, we confirm that a global first-order trend towards depleted values exists. However, a large amount of scatter is superimposed on this geochemical record. In addition, we observe a temporal trend in the amplitude of this residual δ13C variability, which is reproducible for the two studied regions. We suggest that (sub-sea-floor microbial communities and their control on calcite nucleation and ambient porewater dissolved inorganic carbon δ13C pose a viable mechanism to induce bulk-rock δ13C variability. Numerical model calculations highlight that early diagenetic carbonate rock stabilization and linked carbon isotope alteration can be controlled by organic matter supply and subsequent microbial remineralization. A major biotic decline among Late Permian bottom-dwelling organisms facilitated a spatial increase in heterogeneous organic carbon accumulation. Combined with low marine sulfate, this resulted in varying degrees of carbon isotope overprinting. A simulated time series suggests that a 50 % increase in the spatial scatter of organic carbon relative to the average, in addition to an imposed increase in the likelihood of sampling cements formed by microbial calcite nucleation to 1 out of 10 samples, is sufficient to induce the

  3. Latest Permian carbonate carbon isotope variability traces heterogeneous organic carbon accumulation and authigenic carbonate formation

    Science.gov (United States)

    Schobben, Martin; van de Velde, Sebastiaan; Gliwa, Jana; Leda, Lucyna; Korn, Dieter; Struck, Ulrich; Vinzenz Ullmann, Clemens; Hairapetian, Vachik; Ghaderi, Abbas; Korte, Christoph; Newton, Robert J.; Poulton, Simon W.; Wignall, Paul B.

    2017-11-01

    Bulk-carbonate carbon isotope ratios are a widely applied proxy for investigating the ancient biogeochemical carbon cycle. Temporal carbon isotope trends serve as a prime stratigraphic tool, with the inherent assumption that bulk micritic carbonate rock is a faithful geochemical recorder of the isotopic composition of seawater dissolved inorganic carbon. However, bulk-carbonate rock is also prone to incorporate diagenetic signals. The aim of the present study is to disentangle primary trends from diagenetic signals in carbon isotope records which traverse the Permian-Triassic boundary in the marine carbonate-bearing sequences of Iran and South China. By pooling newly produced and published carbon isotope data, we confirm that a global first-order trend towards depleted values exists. However, a large amount of scatter is superimposed on this geochemical record. In addition, we observe a temporal trend in the amplitude of this residual δ13C variability, which is reproducible for the two studied regions. We suggest that (sub-)sea-floor microbial communities and their control on calcite nucleation and ambient porewater dissolved inorganic carbon δ13C pose a viable mechanism to induce bulk-rock δ13C variability. Numerical model calculations highlight that early diagenetic carbonate rock stabilization and linked carbon isotope alteration can be controlled by organic matter supply and subsequent microbial remineralization. A major biotic decline among Late Permian bottom-dwelling organisms facilitated a spatial increase in heterogeneous organic carbon accumulation. Combined with low marine sulfate, this resulted in varying degrees of carbon isotope overprinting. A simulated time series suggests that a 50 % increase in the spatial scatter of organic carbon relative to the average, in addition to an imposed increase in the likelihood of sampling cements formed by microbial calcite nucleation to 1 out of 10 samples, is sufficient to induce the observed signal of carbon

  4. Carbon/Carbon for satellite applications

    Science.gov (United States)

    Meftah, M.; Lee, S.; Irbah, A.; Ostergren, S.

    2011-06-01

    Carbon/Carbon has many attributes that make it an attractive material for satellite applications. It is low in density, is dimensionally stable under a wide variety of conditions, has very low thermal expansion, is relatively low in cost, and is a mature technology. Moreover, the material is flexible enough to enable the designer to select such variables as fiber type, fabric architecture, fiber volume, and high temperature processing and thus custom tailor the physical and mechanical properties to his specific requirements. A wide range of properties are available - densities from 1.5 to 1.9 g/cm3, room temperature Coefficients of Thermal Expansion (CTE) from -0.3x10-6to -1.3x10-6/K, room temperature thermal conductivities from 7 to 210 W/m.K, and modulus from 60 to 190 GPa. A new type of structure developed by CNRS on the space instrument SODISM uses Carbon/Carbon.

  5. Carbon isotopes in mollusk shell carbonates

    Science.gov (United States)

    McConnaughey, Ted A.; Gillikin, David Paul

    2008-10-01

    Mollusk shells contain many isotopic clues about calcification physiology and environmental conditions at the time of shell formation. In this review, we use both published and unpublished data to discuss carbon isotopes in both bivalve and gastropod shell carbonates. Land snails construct their shells mainly from respired CO2, and shell δ13C reflects the local mix of C3 and C4 plants consumed. Shell δ13C is typically >10‰ heavier than diet, probably because respiratory gas exchange discards CO2, and retains the isotopically heavier HCO3 -. Respired CO2 contributes less to the shells of aquatic mollusks, because CO2/O2 ratios are usually higher in water than in air, leading to more replacement of respired CO2 by environmental CO2. Fluid exchange with the environment also brings additional dissolved inorganic carbon (DIC) into the calcification site. Shell δ13C is typically a few ‰ lower than ambient DIC, and often decreases with age. Shell δ13C retains clues about processes such as ecosystem metabolism and estuarine mixing. Ca2+ ATPase-based models of calcification physiology developed for corals and algae likely apply to mollusks, too, but lower pH and carbonic anhydrase at the calcification site probably suppress kinetic isotope effects. Carbon isotopes in biogenic carbonates are clearly complex, but cautious interpretation can provide a wealth of information, especially after vital effects are better understood.

  6. Carbon dioxide sensor

    Science.gov (United States)

    Dutta, Prabir K [Worthington, OH; Lee, Inhee [Columbus, OH; Akbar, Sheikh A [Hilliard, OH

    2011-11-15

    The present invention generally relates to carbon dioxide (CO.sub.2) sensors. In one embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor that incorporates lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3). In another embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor has a reduced sensitivity to humidity due to a sensing electrode with a layered structure of lithium carbonate and barium carbonate. In still another embodiment, the present invention relates to a method of producing carbon dioxide (CO.sub.2) sensors having lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3).

  7. Carbon monoxide poisoning

    OpenAIRE

    Dolan, Michael C.

    1985-01-01

    Carbon monoxide poisoning is a significant cause of illness and death. Its protean symptoms probably lead to a gross underestimation of its true incidence. Low levels of carbon monoxide aggravate chronic cardiopulmonary problems, and high levels are associated with cardiac arrhythmias and cerebral edema. Patients who survive acute poisoning are at risk of delayed neurologic sequelae. The measurement of carboxyhemoglobin levels does not reveal the tissue levels of carbon monoxide but is useful...

  8. Carbon nanotubes decorating methods

    OpenAIRE

    A.D. Dobrzańska-Danikiewicz; Łukowiec, D.; D. Cichock; W. Wolany

    2013-01-01

    Purpose: The work is to present and characterise various methods of depositing carbon nanotubes with nanoparticles of precious metals, and also to present the results of own works concerning carbon nanotubes coated with platinum nanoparticles.Design/methodology/approach: Electron transmission and scanning microscopy has been used for imaging the structure and morphology of the nanocomposites obtained and the distribution of nanoparticles on the surface of carbon nanotubes.Findings: The studie...

  9. Carbon monoxide poisoning (acute)

    OpenAIRE

    Olson, Kent; Smollin, Craig

    2008-01-01

    The main symptoms of carbon monoxide poisoning are non-specific in nature and relate to effects on the brain and heart. The symptoms correlate poorly with serum carboxyhaemoglobin levels. People with comorbidity, the elderly or very young, and pregnant women are most susceptible.Carbon monoxide is produced by the incomplete combustion of carbon fuels, including inadequately ventilated heaters and car exhausts, or from chemicals such as methylene chloride paint stripper.Poisoning is conside...

  10. Carbon monoxide poisoning (acute)

    OpenAIRE

    Smollin, Craig; Olson, Kent

    2010-01-01

    The main symptoms of carbon monoxide poisoning are non-specific in nature and relate to effects on the brain and heart. The symptoms correlate poorly with serum carboxyhaemoglobin levels. People with comorbidity, elderly or very young people, and pregnant women are most susceptible.Carbon monoxide is produced by the incomplete combustion of carbon fuels, including inadequately ventilated heaters and car exhausts, or from chemicals such as methylene chloride paint stripper.Poisoning is cons...

  11. Carbon emissions in China

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhu [Harvard Univ., Cambridge, MA (United States). Sustainability Science Program

    2016-07-01

    This study analyzes the spatial-temporal pattern and processes of China's energy-related carbon emissions. Based on extensive quantitative analysis, it outlines the character and trajectory of China's energy-related carbon emissions during the period 1995-2010, examining the distribution pattern of China's carbon emissions from regional and sectoral perspectives and revealing the driving factors of China's soaring emission increase. Further, the book investigates the supply chain carbon emissions (the carbon footprints) of China's industrial sectors. Anthropogenic climate change is one of the most serious challenges currently facing humankind. China is the world's largest developing country, top primary energy consumer and carbon emitter. Achieving both economic growth and environmental conservation is the country's twofold challenge. Understanding the status, features and driving forces of China's energy-related carbon emissions is a critical aspect of attaining global sustainability. This work, for the first time, presents both key findings on and a systematic evaluation of China's carbon emissions from energy consumption. The results have important implications for global carbon budgets and burden-sharing with regard to climate change mitigation. The book will be of great interest to readers around the world, as it addresses a topic of truly global significance.

  12. Carbon Trading. Literature Overview

    Energy Technology Data Exchange (ETDEWEB)

    Kerste, M.; Weda, J.; Rosenboom, N.

    2010-12-15

    From Pigou and Coase to the Kyoto Protocol, carbon trading has resulted in pricing of the negative externalities emanating from pollution. This report highlights leading literature and empirical findings on carbon trading, amongst others addressing the relevant carbon and related markets, the (lack of) success of carbon trading so far and room for improvement as well as its impact on investments in emission reduction. This report is part of a set of SEO-reports on finance and sustainability. The other reports deal with: Financing the Transition to Sustainable Energy; Innovations in financing environmental and social sustainability; and Sustainable investment.

  13. Holocene carbon cycle dynamics: HOLOCENE CARBON CYCLE DYNAMICS

    National Research Council Canada - National Science Library

    Kleinen, Thomas; Brovkin, Victor; von Bloh, Werner; Archer, David; Munhoven, Guy

    2010-01-01

    .... Apart from the deep sea sediments, important carbon cycle processes considered are carbon uptake or release by the vegetation, carbon uptake by peatlands, and CO2 release due to shallow water sedimentation of CaCO3...

  14. Carbon Dioxide Fountain

    Science.gov (United States)

    Kang, Seong-Joo; Ryu, Eun-Hee

    2007-01-01

    This article presents the development of a carbon dioxide fountain. The advantages of the carbon dioxide fountain are that it is odorless and uses consumer chemicals. This experiment also is a nice visual experiment that allows students to see evidence of a gaseous reagent being consumed when a pressure sensor is available. (Contains 3 figures.)…

  15. Carbon dioxide recycling

    Science.gov (United States)

    The recycling of carbon dioxide to methanol and dimethyl ether is seen to offer a substantial route to renewable and environmentally carbon neutral fuels. One of the authors has championed the “Methanol Economy" in articles and a book. By recycling ambient CO2, the authors argue ...

  16. Carbon for sensing devices

    CERN Document Server

    Tagliaferro, Alberto

    2015-01-01

    This book reveals why carbon is playing such an increasingly prominent role as a sensing material. The various steps that transform a raw material in a sensing device are thoroughly presented and critically discussed.  The authors deal with all aspects of carbon-based sensors, starting from the various hybridization and allotropes of carbon, with specific focus on micro and nanosized carbons (e.g., carbon nanotubes, graphene) and their growth processes. The discussion then moves to the role of functionalization and the different routes to achieve it. Finally, a number of sensing applications in various fields are presented, highlighting the connection with the basic properties of the various carbon allotropes.  Readers will benefit from this book’s bottom-up approach, which starts from the local bonding in carbon solids and ends with sensing applications, linking the local hybridization of carbon atoms and its modification by functionalization to specific device performance. This book is a must-have in th...

  17. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... and Bans Report an Unsafe Product Consumers Businesses Home Safety Education Safety Education Centers Carbon Monoxide Information Center Carbon ... All CO Safety Guides ")); jQuery(".node-type-safety-education-center ... Camping Equipment Home Heating Equipment On Safety Blogs: CO Safety More ...

  18. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... main content Languages 简体中文 English Bahasa Indonesia 한국어 Español ภาษาไทย Tiếng Việt Text Size: Decrease Font Increase ... Monoxide Information Center Carbon Monoxide Information Center En Español The Invisible Killer Carbon monoxide, also known as ...

  19. Petroleum-derived carbons

    Energy Technology Data Exchange (ETDEWEB)

    Bacha, J.D.; Newman, J.W.; White, J.L. (eds.)

    1986-01-01

    The 25 typescript papers in this volume derive from an ACS symposium held at an undisclosed site and date. They are concerned with such subjects as coke, carbon composites, the carbonization process, surface area, etc., and are accompanied by a 12-page index.

  20. Carbon monoxide poisoning

    Science.gov (United States)

    ... Animals can also be poisoned by carbon monoxide. People who have pets at home may notice that their animals become ... or unresponsive from carbon monoxide exposure. Often the pets will ... these conditions. This can lead to a delay in getting help.

  1. Amorphous iron (II) carbonate

    DEFF Research Database (Denmark)

    Sel, Ozlem; Radha, A.V.; Dideriksen, Knud

    2012-01-01

    Abstract The synthesis, characterization and crystallization energetics of amorphous iron (II) carbonate (AFC) are reported. AFC may form as a precursor for siderite (FeCO3). The enthalpy of crystallization (DHcrys) of AFC is similar to that of amorphous magnesium carbonate (AMC) and more...

  2. Global Carbon Budget 2015

    NARCIS (Netherlands)

    Le Quere, C.; Moriarty, R.; Andrew, R.M.; Canadell, J.G.; Sitch, S.; Korsbakken, J.I.; Friedlingstein, P.; Peters, G.P.; Andres, R.J.; Boden, T.A.; Houghton, R.A.; House, J.I.; Keeling, R.F.; Tans, P.; Arneth, A.; Bakker, D.C.E.; Barbero, L.; Bopp, L.; Chang, J.; Chevallier, F.; Chini, L.P.; Ciais, P.; Fader, M.; Feely, R.A.; Gkritzalis, T.; Harris, I.; Hauck, J.; Ilyina, T.; Jain, A.K.; Kato, E.; Kitidis, V.; Goldewijk, K.K.; Koven, C.; Landschuetzer, P.; Lauvset, S.K.; Lefevre, N.; Lenton, A.; Lima, I.D.; Metzl, N.; Millero, F.; Munro, D.R.; Murata, A.; Nabel, J.E.M.S.; Nakaoka, S.; Nojiri, Y.; O'Brien, K.; Olsen, A.; Ono, T.; Perez, F.F.; Pfeil, B.; Pierrot, D.; Poulter, B.; Rehder, G.; Roedenbeck, C.; Saito, S.; Schuster, U.; Schwinger, J.; Seferian, R.; Steinhoff, T.; Stocker, B.D.; Sutton, A.J.; Takahashi, T.; Tilbrook, B.; van der Laan-Luijkx, I.T.; van der Werf, G.R.; van Heuven, S.; Vandemark, D.; Viovy, N.; Wiltshire, A.; Zaehle, S.; Zeng, N.

    2015-01-01

    Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we

  3. Global Carbon Budget 2015

    NARCIS (Netherlands)

    Quéré, Le C.; Moriarty, R.; Andrew, R.M.; Canadell, J.G.; Sitch, S.; Korsbakken, J.I.; Friedlingstein, P.; Peters, G.P.; Andres, R.J.; Boden, T.A.; Houghton, R.A.; House, J.I.; Keeling, R.F.; Tans, P.; Arneth, A.; Bakker, D.C.E.; Barbero, L.; Bopp, L.; Chang, J.; Chevallier, F.; Chini, L.P.; Ciais, P.; Fader, M.; Feely, R.A.; Gkritzalis, T.; Harris, I.; Hauck, J.; Ilyina, T.; Jain, A.K.; Kato, E.; Kitidis, V.; Klein Goldewijk, K.; Koven, C.; Landschützer, P.; Lauvset, S.K.; Lefèvre, N.; Lenton, A.; Lima, I.D.; Metzl, N.; Millero, F.; Munro, D.R.; Murata, A.; Nabel, J.E.M.S.; Nakaoka, S.; Nojiri, Y.; O'Brien, K.; Olsen, A.; Ono, T.; Pérez, F.F.; Pfeil, B.; Pierrot, D.; Poulter, B.; Rehder, G.; Rödenbeck, C.; Saito, S.; Schuster, U.; Schwinger, J.; Séférian, R.; Steinhoff, T.; Stocker, B.D.; Sutton, A.J.; Takahashi, T.; Tilbrook, B.; Laan-Luijkx, Van Der I.T.; Werf, Van Der G.R.; Heuven, Van S.; Vandemark, D.; Viovy, N.; Wiltshire, A.; Zaehle, S.; Zeng, N.

    2015-01-01

    Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we

  4. Carbon Capture and Storage

    NARCIS (Netherlands)

    Benson, S.M.; Bennaceur, K.; Cook, P.; Davison, J.; Coninck, H. de; Farhat, K.; Ramirez, C.A.; Simbeck, D.; Surles, T.; Verma, P.; Wright, I.

    2012-01-01

    Emissions of carbon dioxide, the most important long-lived anthropogenic greenhouse gas, can be reduced by Carbon Capture and Storage (CCS). CCS involves the integration of four elements: CO 2 capture, compression of the CO2 from a gas to a liquid or a denser gas, transportation of pressurized CO 2

  5. Carbon nanotubes cement composites

    OpenAIRE

    Simone Musso; Jean-Marc Tulliani; Giuseppe Ferro

    2011-01-01

    The present paper reviews the current state of the art of carbon nanotubes cement-based composites and the possible applications. The influence of carbon nanotubes additions onto cement paste mechanical and electrical properties are discussed in detail. Though promising, several challenges have still to be solved before the introduction of these new materials into the public sphere through civil infrastructures.

  6. Seeing the Carbon Cycle

    Science.gov (United States)

    Drouin, Pamela; Welty, David J.; Repeta, Daniel; Engle-Belknap, Cheryl A.; Cramer, Catherine; Frashure, Kim; Chen, Robert

    2006-01-01

    In this article, the authors present a classroom experiment that was developed to introduce middle school learners to the carbon cycle. The experiment deals with transfer of CO[subscript 2] between liquid reservoirs and the effect CO[subscript 2] has on algae growth. It allows students to observe the influence of the carbon cycle on algae growth,…

  7. The carbon cycle revisited

    Science.gov (United States)

    Bolin, Bert; Fung, Inez

    1992-01-01

    Discussions during the Global Change Institute indicated a need to present, in some detail and as accurately as possible, our present knowledge about the carbon cycle, the uncertainties in this knowledge, and the reasons for these uncertainties. We discuss basic issues of internal consistency within the carbon cycle, and end by summarizing the key unknowns.

  8. (PSLW) Activated Carbon

    African Journals Online (AJOL)

    ADOWIE PERE

    2017-12-02

    Dec 2, 2017 ... ABSTRACT: Silver-impregnated carbon (SIC) and its precursor (un-impregnated) derived from an easily available low cost plant material Prosopis spicigera L. wood (PSLW) carbon was investigated for their ability to remove arsenic from aqueous solutions in batch and column experiments. Arsenic uptake ...

  9. Soil carbon: Depth of understanding

    Science.gov (United States)

    Ahrens, Bernhard; Reichstein, Markus

    2017-11-01

    Earth system models disagree on the fate of soil organic carbon under climate change. Reproducing spatial patterns of the climatological temperature sensitivity of soil carbon is a necessary condition for trustworthy simulations of the carbon-cycle-climate feedback.

  10. Resistivity of Carbon-Carbon Composites Halved

    Science.gov (United States)

    Gaier, James R.

    2004-01-01

    Carbon-carbon composites have become the material of choice for applications requiring strength and stiffness at very high temperatures (above 2000 C). These composites comprise carbon or graphite fibers embedded in a carbonized or graphitized matrix. In some applications, such as shielding sensitive electronics in very high temperature environments, the performance of these materials would be improved by lowering their electrical resistivity. One method to lower the resistivity of the composites is to lower the resistivity of the graphite fibers, and a proven method to accomplish that is intercalation. Intercalation is the insertion of guest atoms or molecules into a host lattice. In this study the host fibers were highly graphitic pitch-based graphite fibers, or vapor-grown carbon fibers (VGCF), and the intercalate was bromine. Intercalation compounds of graphite are generally thought of as being only metastable, but it has been shown that the residual bromine graphite fiber intercalation compound is remarkably stable, resisting decomposition even at temperatures at least as high as 1000 C. The focus of this work was to fabricate composite preforms, determine whether the fibers they were made from were still intercalated with bromine after processing, and determine the effect on composite resistivity. It was not expected that the resistivity would be lowered as dramatically as with graphite polymer composites because the matrix itself would be much more conductive, but it was hoped that the gains would be substantial enough to warrant its use in high-performance applications. In a collaborative effort supporting a Space Act Agreement between the NASA Glenn Research Center and Applied Sciences, Inc. (Cedarville, OH), laminar preforms were fabricated with pristine and bromine-intercalated pitch-based fibers (P100 and P100-Br) and VGCF (Pyro I and Pyro I-Br). The green preforms were carbonized at 1000 C and then heat treated to 3000 C. To determine whether the

  11. Fiber-Matrix Interphase Development in Carbon/Carbon Composites

    National Research Council Canada - National Science Library

    Rellick, G

    1998-01-01

    In carbon/carbon (C/C) composites-i.e., a composite in which a carbon matrix is reinforced with carbon fiber when the matrix is derived from a thermosetting resin, we always observe a distinct, highly graphitizable, and well-oriented...

  12. Authigenic carbonate and the history of the global carbon cycle.

    Science.gov (United States)

    Schrag, Daniel P; Higgins, John A; Macdonald, Francis A; Johnston, David T

    2013-02-01

    We present a framework for interpreting the carbon isotopic composition of sedimentary rocks, which in turn requires a fundamental reinterpretation of the carbon cycle and redox budgets over Earth's history. We propose that authigenic carbonate, produced in sediment pore fluids during early diagenesis, has played a major role in the carbon cycle in the past. This sink constitutes a minor component of the carbon isotope mass balance under the modern, high levels of atmospheric oxygen but was much larger in times of low atmospheric O(2) or widespread marine anoxia. Waxing and waning of a global authigenic carbonate sink helps to explain extreme carbon isotope variations in the Proterozoic, Paleozoic, and Triassic.

  13. Porous carbons prepared by direct carbonization of MOFs for supercapacitors

    Science.gov (United States)

    Yan, Xinlong; Li, Xuejin; Yan, Zifeng; Komarneni, Sridhar

    2014-07-01

    Three porous carbons were prepared by direct carbonization of HKUST-1, MOF-5 and Al-PCP without additional carbon precursors. The carbon samples obtained by carbonization at 1073 K were characterized by XRD, TEM and N2 physisorption techniques followed by testing for electrochemical performance. The BET surface areas of the three carbons were in the range of 50-1103 m2/g. As electrode materials for supercapacitor, the MOF-5 and Al-PCP derived carbons displayed the ideal capacitor behavior, whereas the HKUST-1 derived carbon showed poor capacitive behavior at various sweep rates and current densities. Among those carbon samples, Al-PCP derived carbons exhibited highest specific capacitance (232.8 F/g) in 30% KOH solution at the current density of 100 mA/g.

  14. Carbon aerogels; Les aerogels de carbone

    Energy Technology Data Exchange (ETDEWEB)

    Berthon-Fabry, S.; Achard, P

    2003-06-15

    The carbon aerogel is a nano-porous material at open porosity, electrical conductor. The aerogels morphology is variable in function of the different synthesis parameters. This characteristic offers to the aerogels a better adaptability to many applications: electrodes (super condensers, fuel cells). The author presents the materials elaboration and their applications. It provides also the research programs: fundamental research, realization of super-condenser electrodes, fuel cells electrodes, gas storage materials and opaque materials for thermal insulation. (A.L.B.)

  15. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... On Safety Blogs: CO Safety More CO Blogs Research & Statistics JANUARY 07, 2016 Non-Fire Carbon Monoxide ... the information it contains. You may wish to review the privacy policy of the external site as ...

  16. Transport in Carbon Nanotubes

    Science.gov (United States)

    Datta, S.; Xue, Yong-Qinag; Anantram, M. P.; Saini, Subhash (Technical Monitor)

    1999-01-01

    This presentation discusses coupling between carbon nanotubes (CNT), simple metals (FEG) and a graphene sheet. The graphene sheet did not couple well with FEG, but the combination of a graphene strip and CNT did couple well with most simple metals.

  17. Hydropower's Biogenic Carbon Footprint

    National Research Council Canada - National Science Library

    Scherer, Laura; Pfister, Stephan

    2016-01-01

    .... Little is known about the severity of their emissions at the global scale. Here we show that the carbon footprint of hydropower is far higher than previously assumed, with a global average of 173 kg CO2...

  18. Carbon nanotubes for supercapacitor

    National Research Council Canada - National Science Library

    Pan, Hui; Li, Jianyi; Feng, Yuanping

    2010-01-01

    .... The purpose is to give a comprehensive understanding of the advantages and disadvantages of carbon nanotubes-related supercapacitor materials and to find ways for the improvement in the performance of supercapacitor...

  19. Sodium carbonate poisoning

    Science.gov (United States)

    Sodium carbonate is found in: Automatic dishwashing soaps Clinitest (diabetes testing) tablets Glass products Pulp and paper products Some bleaches Some bubble bath solutions Some steam iron cleaners Note: This list is not all-inclusive.

  20. Total Ecosystem Carbon Stock

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Total ecosystem carbon includes above- and below-ground live plant components (such as leaf, branch, stem and root), dead biomass (such as standing dead wood, down...

  1. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... CONSUMER PRODUCT SAFETY COMMISSION Search CPSC Search Menu Home Recalls Recall List CPSC Recall API Recall Lawsuits ... and Bans Report an Unsafe Product Consumers Businesses Home Safety Education Safety Education Centers Carbon Monoxide Information ...

  2. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Statistics JANUARY 07, 2016 Non-Fire Carbon Monoxide Deaths Associated with the Use of Consumer Products 2012 Annual Estimates OCTOBER 13, 2015 Incidents, Deaths, and In-Depth Investigations Associated with Non-Fire ...

  3. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Import Surveillance International Recall Guidance Civil and Criminal Penalties Federal Court Orders & ... 07, 2016 Non-Fire Carbon Monoxide Deaths Associated with the Use of Consumer Products 2012 ...

  4. Carbon Monoxide Nonattainment Areas

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer identifies areas in the U.S. where air pollution levels have not met the National Ambient Air Quality Standards (NAAQS) for Carbon Monoxide and have...

  5. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Safety Blogs: CO Safety More CO Blogs Research & Statistics JANUARY 07, 2016 Non-Fire Carbon Monoxide Deaths ... 2011 Annual Estimates View All CO-Related Injury Statistics and Technical Reports Related Links Recalls Safety Education ...

  6. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Unites States die every year from accidental non-fire related CO poisoning associated with consumer products, including ... CO Blogs Research & Statistics JANUARY 07, 2016 Non-Fire Carbon Monoxide Deaths Associated with the Use of ...

  7. Carbon nanotube biosensors

    National Research Council Canada - National Science Library

    Tîlmaciu, Carmen-Mihaela; Morris, May C

    2015-01-01

    .... In particular, carbon nanotubes (CNTs) can serve as scaffolds for immobilization of biomolecules at their surface, and combine several exceptional physical, chemical, electrical, and optical characteristics properties which make them one...

  8. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... vented fuel-burning appliances such as furnaces, stoves, water heaters and fireplaces. Watch This Video View CO Safety Tips Featured Resources CPSC announces winners of carbon monoxide poster contest ...

  9. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Community Outreach Resource Center Toy Recall Statistics CO Poster Contest Pool Safely Business & Manufacturing Business & Manufacturing Business ... Featured Resources CPSC announces winners of carbon monoxide poster contest Video View the blog Clues You Can ...

  10. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... On Safety Blogs: CO Safety More CO Blogs Research & Statistics JANUARY 07, 2016 Non-Fire Carbon Monoxide ... Related Links Recalls Safety Education Regulations, Laws & Standards Research & Statistics Business & Manufacturing Small Business Resources OnSafety Blogs ...

  11. Morphing Carbon Nanotube Microstructures

    Science.gov (United States)

    2015-02-20

    muscle inspired by spider dragline silk. Nat. Commun. 5, 3322 (2014). 13. Hart, A. J. & Slocum , A. H. Rapid Growth and Flow-Mediated Nucleation of...Phys. Lett. 87, 123110 (2005). 15. A. J. Hart, A. H. Slocum . Rapid growth and flow-mediated nucleation of millimeter-scale aligned carbon nanotube... Slocum , B. L. Wardle. High-yield growth and morphology control of aligned carbon nanotubes on ceramic fibers for multifunctional enhancement of

  12. Applications for alliform carbon

    Energy Technology Data Exchange (ETDEWEB)

    Gogotsi, Yury; Mochalin, Vadym; McDonough, IV, John Kenneth; Simon, Patrice; Taberna, Pierre Louis

    2017-02-21

    This invention relates to novel applications for alliform carbon, useful in conductors and energy storage devices, including electrical double layer capacitor devices and articles incorporating such conductors and devices. Said alliform carbon particles are in the range of 2 to about 20 percent by weight, relative to the weight of the entire electrode. Said novel applications include supercapacitors and associated electrode devices, batteries, bandages and wound healing, and thin-film devices, including display devices.

  13. Growing carbon nanotubes

    OpenAIRE

    Ando, Yoshinori; Zhao, Xinluo; Sugai, Toshiki; Kumar, Mukul

    2004-01-01

    The discovery of ‘fullerenes’ added a new dimension to the knowledge of carbon science1; and the subsequent discovery of ‘carbon nanotubes’ (CNTs, the elongated fullerene) added a new dimension to the knowledge of technology2;. Today, ‘nanotechnology’ is a hot topic attracting scientists, industrialists, journalists, governments, and even the general public. Nanotechnology is the creation of functional materials, devices, and systems through control of matter on the nanometer scale and the ex...

  14. Carbon Nanotubes in Neuroscience

    OpenAIRE

    Malarkey, Erik B.; Parpura, Vladimir

    2010-01-01

    Carbon nanotubes have electrical, mechanical and chemical properties that make them one of the most promising materials for applications in neuroscience. Single-walled and multi-walled carbon nanotubes have been increasingly used as scaffolds for neuronal growth and more recently for neural stem cell growth and differentiation. They are also used in interfaces with neurons, where they can detect neuronal electrical activity and also deliver electrical stimulation to these cells. The emerging ...

  15. Carbon based prosthetic devices

    Energy Technology Data Exchange (ETDEWEB)

    Devlin, D.J.; Carroll, D.W.; Barbero, R.S.; Archuleta, T. [Los Alamos National Lab., NM (US); Klawitter, J.J.; Ogilvie, W.; Strzepa, P. [Ascension Orthopedics (US); Cook, S.D. [Tulane Univ., New Orleans, LA (US). School of Medicine

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objective was to evaluate the use of carbon/carbon-fiber-reinforced composites for use in endoprosthetic devices. The application of these materials for the metacarpophalangeal (MP) joints of the hand was investigated. Issues concerning mechanical properties, bone fixation, biocompatibility, and wear are discussed. A system consisting of fiber reinforced materials with a pyrolytic carbon matrix and diamond-like, carbon-coated wear surfaces was developed. Processes were developed for the chemical vapor infiltration (CVI) of pyrolytic carbon into porous fiber preforms with the ability to tailor the outer porosity of the device to provide a surface for bone in-growth. A method for coating diamond-like carbon (DLC) on the articulating surface by plasma-assisted chemical vapor deposition (CVD) was developed. Preliminary results on mechanical properties of the composite system are discussed and initial biocompatibility studies were performed.

  16. Carbon dioxide as chemical feedstock

    National Research Council Canada - National Science Library

    Aresta, M

    2010-01-01

    ... Dioxide as an Inert Solvent for Chemical Syntheses 15 Alessandro Galia and Giuseppe Filardo Introduction 15 Dense Carbon Dioxide as Solvent Medium for Chemical Processes 15 Enzymatic Catalysis in Dense Carbon Dioxide 18 Other Reactions in Dense Carbon Dioxide 19 Polymer Synthesis in Supercritical Carbon Dioxide 20 Chain Polymerizations: Synt...

  17. Method for synthesizing carbon nanotubes

    Science.gov (United States)

    Fan, Hongyou

    2012-09-04

    A method for preparing a precursor solution for synthesis of carbon nanomaterials, where a polar solvent is added to at least one block copolymer and at least one carbohydrate compound, and the precursor solution is processed using a self-assembly process and subsequent heating to form nanoporous carbon films, porous carbon nanotubes, and porous carbon nanoparticles.

  18. Black carbon in marine sediments

    NARCIS (Netherlands)

    Middelburg, J.J.; Nieuwenhuize, J.; Van Breugel, P.

    1999-01-01

    Concentrations of black carbon were determined for a number of marine sediments. A comparison of black carbon based on thermal oxidation and hot concentrated nitric acid pretreatments revealed that the latter significantly overestimates combustion derived carbon phases. Black carbon accounts for

  19. Programmable high crystallinity carbon patterns

    Science.gov (United States)

    Wang, Xuewen; Wang, Hong; Gu, Yang; Fu, Wei; Zheng, Lu; Liu, Guowei; He, Yongmin; Long, Yi; Zhao, Wu; Zhang, Jie; Zhang, Ting; Liu, Zheng

    2017-06-01

    Carbon nanomaterials such as carbon nanotube and graphene are promising candidates for next-generation flexible electronics. However, the practical application of carbon electronics requires controlled fabrication of those materials with micro-patterned structures on flexible substrate at wafer-scale and low cost. Inspiring from the conventional photolithography process and pyrolysis of photoresist, herein, we demonstrate the synthesis of high-quality micro-patterned high crystallinity carbon. The method employed pre-patterned pyrolyzed photoresist as carbon precursors, in order to minimize the mobility of carbon during the high temperature growth, which results into high quality carbon patterns with a lateral resolution up to ~2 µm. The flexible carbon electronics are demonstrated by transferring the as-patterned high crystallinity carbon patterns to the flexible substrate, and showing asymmetric tensile-compressive response with high output resolution. These results will pave the way to the next-generation carbon-based flexible electronics and mechanical sensors.

  20. Nanoporous metal-carbon composite

    Energy Technology Data Exchange (ETDEWEB)

    Worsley, Marcus A.; Satcher, Joe; Kucheyev, Sergei; Charnvanichborikarn, Supakit; Colvin, Jeffrey; Felter, Thomas; Kim, Sangil; Merrill, Matthew; Orme, Christine

    2017-12-19

    Described here is a metal-carbon composite, comprising (a) a porous three-dimensional scaffold comprising one or more of carbon nanotubes, graphene and graphene oxide, and (b) metal nanoparticles disposed on said porous scaffold, wherein the metal-carbon composite has a density of 1 g/cm.sup.3 or less, and wherein the metal nanoparticles account for 1 wt. % or more of the metal-carbon composite. Also described are methods for making the metal-carbon composite.

  1. Stable prenucleation calcium carbonate clusters

    OpenAIRE

    Gebauer, Denis; Völkel, Antje; Cölfen, Helmut

    2008-01-01

    Calcium carbonate forms scales, geological deposits, biominerals, and ocean sediments. Huge amounts of carbon dioxide are retained as carbonate ions, and calcium ions represent a major contribution to water hardness. Despite its relevance, little is known about the precipitation mechanism of calcium carbonate, and specified complex crystal structures challenge the classical view on nucleation considering the formation of metastable ion clusters. We demonstrate that dissolved calcium carbonate...

  2. Implications of carbon dust emission for terrestrail carbon cycling and carbon accounting

    Science.gov (United States)

    Wind erosion preferentially removes the finest carbon- and nutrient-rich soil fractions, and consequently its role may be significant within terrestrial carbon (C) cycles. However, the impacts of wind erosion on soil organic carbon (SOC) redistribution are not considered in most carbon cycle models,...

  3. Global carbon inequality

    Energy Technology Data Exchange (ETDEWEB)

    Hubacek, Klaus [University of Maryland, Department of Geographical Sciences, College Park, MD (United States); Masaryk University, Department of Environmental Studies, Brno (Czech Republic); Baiocchi, Giovanni [University of Maryland, Department of Geographical Sciences, College Park, MD (United States); University of Maryland, Department of Economics, College Park, MD (United States); Feng, Kuishuang [University of Maryland, Department of Geographical Sciences, College Park, MD (United States); Munoz Castillo, Raul [University of Maryland, Department of Geographical Sciences, College Park, MD (United States); Interamerican Development Bank, Washington, DC (United States); Sun, Laixiang [University of Maryland, Department of Geographical Sciences, College Park, MD (United States); SOAS, University of London, London (United Kingdom); International Institute for Applied Systems Analysis (IIASA), Laxenburg (Austria); Xue, Jinjun [Nagoya University, Graduate School of Economics, Nagoya (Japan); Hubei University of Economics, Wuhan (China)

    2017-12-01

    Global climate change and inequality are inescapably linked both in terms of who contributes climate change and who suffers the consequences. This fact is also partly reflected in two United Nations (UN) processes: on the one hand, the Paris Agreement of the UN Framework Convention on Climate Change under which countries agreed to hold the increase in the global average temperature to below 2 C above pre-industrial levels and, on the other hand, the UN's Sustainable Development Goals aiming to end poverty. These agreements are seen as important foundation to put the world nations on a sustainable pathway. However, how these agreements can be achieved or whether they are even mutually compatible is less clear. We explore the global carbon inequality between and within countries and the carbon implications of poverty alleviation by combining detailed consumer expenditure surveys for different income categories for a wide range of countries with an environmentally extended multi-regional input-output approach to estimate carbon footprints of different household groups, globally, and assess the carbon implications of moving the poorest people out of poverty. Given the current context, increasing income leads to increasing carbon footprints and makes global targets for mitigating greenhouse gases more difficult to achieve given the pace of technological progress and current levels of fossil fuel dependence. We conclude that the huge level of carbon inequality requires a critical discussion of undifferentiated income growth. Current carbon-intensive lifestyles and consumption patterns need to enter the climate discourse to a larger extent. (orig.)

  4. Measurement of carbon capture efficiency and stored carbon leakage

    Science.gov (United States)

    Keeling, Ralph F.; Dubey, Manvendra K.

    2013-01-29

    Data representative of a measured carbon dioxide (CO.sub.2) concentration and of a measured oxygen (O.sub.2) concentration at a measurement location can be used to determine whether the measured carbon dioxide concentration at the measurement location is elevated relative to a baseline carbon dioxide concentration due to escape of carbon dioxide from a source associated with a carbon capture and storage process. Optionally, the data can be used to quantify a carbon dioxide concentration increase at the first location that is attributable to escape of carbon dioxide from the source and to calculate a rate of escape of carbon dioxide from the source by executing a model of gas-phase transport using at least the first carbon dioxide concentration increase. Related systems, methods, and articles of manufacture are also described.

  5. Terrestrial Carbon Cycle Variability.

    Science.gov (United States)

    Baldocchi, Dennis; Ryu, Youngryel; Keenan, Trevor

    2016-01-01

    A growing literature is reporting on how the terrestrial carbon cycle is experiencing year-to-year variability because of climate anomalies and trends caused by global change. As CO 2 concentration records in the atmosphere exceed 50 years and as satellite records reach over 30 years in length, we are becoming better able to address carbon cycle variability and trends. Here we review how variable the carbon cycle is, how large the trends in its gross and net fluxes are, and how well the signal can be separated from noise. We explore mechanisms that explain year-to-year variability and trends by deconstructing the global carbon budget. The CO 2 concentration record is detecting a significant increase in the seasonal amplitude between 1958 and now. Inferential methods provide a variety of explanations for this result, but a conclusive attribution remains elusive. Scientists have reported that this trend is a consequence of the greening of the biosphere, stronger northern latitude photosynthesis, more photosynthesis by semi-arid ecosystems, agriculture and the green revolution, tropical temperature anomalies, or increased winter respiration. At the global scale, variability in the terrestrial carbon cycle can be due to changes in constituent fluxes, gross primary productivity, plant respiration and heterotrophic (microbial) respiration, and losses due to fire, land use change, soil erosion, or harvesting. It remains controversial whether or not there is a significant trend in global primary productivity (due to rising CO 2 , temperature, nitrogen deposition, changing land use, and preponderance of wet and dry regions). The degree to which year-to-year variability in temperature and precipitation anomalies affect global primary productivity also remains uncertain. For perspective, interannual variability in global gross primary productivity is relatively small (on the order of 2 Pg-C y -1 ) with respect to a large and uncertain background (123 +/- 4 Pg-C y -1 ), and

  6. Composition of carbonization residues

    Energy Technology Data Exchange (ETDEWEB)

    Hupfer; Leonhardt

    1943-11-27

    This report compared the composition of samples from Wesseling and Leuna. In each case the sample was a residue from carbonization of the residues from hydrogenation of the brown coal processed at the plant. The composition was given in terms of volatile components, fixed carbon, ash, water, carbon, hydrogen, oxygen, nitrogen, volatile sulfur, and total sulfur. The result of carbonization was given in terms of (ash and) coke, tar, water, gas and losses, and bitumen. The composition of the ash was given in terms of silicon dioxide, ferric oxide, aluminum oxide, calcium oxide, magnesium oxide, potassium and sodium oxides, sulfur trioxide, phosphorus pentoxide, chlorine, and titanium oxide. The most important difference between the properties of the two samples was that the residue from Wesseling only contained 4% oil, whereas that from Leuna had about 26% oil. Taking into account the total amount of residue processed yearly, the report noted that better carbonization at Leuna could save 20,000 metric tons/year of oil. Some other comparisons of data included about 33% volatiles at Leuna vs. about 22% at Wesseling, about 5 1/2% sulfur at Leuna vs. about 6 1/2% at Leuna, but about 57% ash for both. Composition of the ash differed quite a bit between the two. 1 table.

  7. Carbon fuel particles used in direct carbon conversion fuel cells

    Science.gov (United States)

    Cooper, John F.; Cherepy, Nerine

    2012-10-09

    A system for preparing particulate carbon fuel and using the particulate carbon fuel in a fuel cell. Carbon particles are finely divided. The finely dividing carbon particles are introduced into the fuel cell. A gas containing oxygen is introduced into the fuel cell. The finely divided carbon particles are exposed to carbonate salts, or to molten NaOH or KOH or LiOH or mixtures of NaOH or KOH or LiOH, or to mixed hydroxides, or to alkali and alkaline earth nitrates.

  8. Chemically modified carbonic anhydrases useful in carbon capture systems

    Science.gov (United States)

    Novick, Scott; Alvizo, Oscar

    2013-01-15

    The present disclosure relates to chemically modified carbonic anhydrase polypeptides and soluble compositions, homogenous liquid formulations comprising them. The chemically modified carbonic anhydrase polypeptides have improved properties relative to the same carbonic anhydrase polypeptide that is not chemically modified including the improved properties of increased activity and/or stability in the presence of amine compounds, ammonia, or carbonate ion. The present disclosure also provides methods of preparing the chemically modified polypeptides and methods of using the chemically modified polypeptides for accelerating the absorption of carbon dioxide from a gas stream into a solution as well as for the release of the absorbed carbon dioxide for further treatment and/or sequestering.

  9. Chemically modified carbonic anhydrases useful in carbon capture systems

    Energy Technology Data Exchange (ETDEWEB)

    Novick, Scott J; Alvizo, Oscar

    2013-10-29

    The present disclosure relates to chemically modified carbonic anhydrase polypeptides and soluble compositions, homogenous liquid formulations comprising them. The chemically modified carbonic anhydrase polypeptides have improved properties relative to the same carbonic anhydrase polypeptide that is not chemically modified including the improved properties of increased activity and/or stability in the presence of amine compounds, ammonia, or carbonate ion. The present disclosure also provides methods of preparing the chemically modified polypeptides and methods of using the chemically modified polypeptides for accelerating the absorption of carbon dioxide from a gas stream into a solution as well as for the release of the absorbed carbon dioxide for further treatment and/or sequestering.

  10. Carbon Nanotubes for Supercapacitor

    Science.gov (United States)

    2010-01-01

    As an electrical energy storage device, supercapacitor finds attractive applications in consumer electronic products and alternative power source due to its higher energy density, fast discharge/charge time, low level of heating, safety, long-term operation stability, and no disposable parts. This work reviews the recent development of supercapacitor based on carbon nanotubes (CNTs) and their composites. The purpose is to give a comprehensive understanding of the advantages and disadvantages of carbon nanotubes-related supercapacitor materials and to find ways for the improvement in the performance of supercapacitor. We first discussed the effects of physical and chemical properties of pure carbon nanotubes, including size, purity, defect, shape, functionalization, and annealing, on the supercapacitance. The composites, including CNTs/oxide and CNTs/polymer, were further discussed to enhance the supercapacitance and keep the stability of the supercapacitor by optimally engineering the composition, particle size, and coverage. PMID:20672061

  11. Carbon Nanotubes for Supercapacitor

    Directory of Open Access Journals (Sweden)

    Li Jianyi

    2010-01-01

    Full Text Available Abstract As an electrical energy storage device, supercapacitor finds attractive applications in consumer electronic products and alternative power source due to its higher energy density, fast discharge/charge time, low level of heating, safety, long-term operation stability, and no disposable parts. This work reviews the recent development of supercapacitor based on carbon nanotubes (CNTs and their composites. The purpose is to give a comprehensive understanding of the advantages and disadvantages of carbon nanotubes-related supercapacitor materials and to find ways for the improvement in the performance of supercapacitor. We first discussed the effects of physical and chemical properties of pure carbon nanotubes, including size, purity, defect, shape, functionalization, and annealing, on the supercapacitance. The composites, including CNTs/oxide and CNTs/polymer, were further discussed to enhance the supercapacitance and keep the stability of the supercapacitor by optimally engineering the composition, particle size, and coverage.

  12. Carbon nanotubes for supercapacitor.

    Science.gov (United States)

    Pan, Hui; Li, Jianyi; Feng, Yuanping

    2010-01-05

    As an electrical energy storage device, supercapacitor finds attractive applications in consumer electronic products and alternative power source due to its higher energy density, fast discharge/charge time, low level of heating, safety, long-term operation stability, and no disposable parts. This work reviews the recent development of supercapacitor based on carbon nanotubes (CNTs) and their composites. The purpose is to give a comprehensive understanding of the advantages and disadvantages of carbon nanotubes-related supercapacitor materials and to find ways for the improvement in the performance of supercapacitor. We first discussed the effects of physical and chemical properties of pure carbon nanotubes, including size, purity, defect, shape, functionalization, and annealing, on the supercapacitance. The composites, including CNTs/oxide and CNTs/polymer, were further discussed to enhance the supercapacitance and keep the stability of the supercapacitor by optimally engineering the composition, particle size, and coverage.

  13. The Carbon Trading Game

    Energy Technology Data Exchange (ETDEWEB)

    Fouquet, Roger [Environmental Policy and Management Group, Imperial College London, Prince Consort Road, London SW7 2BP (United Kingdom)

    2003-12-01

    In response to the Kyoto Protocol, an international market for carbon dioxide tradable permits is likely to be created. Two of the key issues involved are explaining the concepts of tradable permits to industrialists, policy-makers and the man on the street, and anticipating how the market will evolve. A simple game of the market for carbon dioxide tradable permits has been developed and used that can help deal with both issues. As a pedagogical tool, this game benefits from simplicity (just a few pieces of paper are needed) and enables students to grasp the concepts and remember them through the intensity and fun of a trading 'pit'. The experiences also provide substantial insights into the evolution of the carbon dioxide permit market, particularly related to the evolution of trade volume, permit prices and country strategies.

  14. Flexible Carbon Aerogels

    Directory of Open Access Journals (Sweden)

    Marina Schwan

    2016-09-01

    Full Text Available Carbon aerogels are highly porous materials with a large inner surface area. Due to their high electrical conductivity they are excellent electrode materials in supercapacitors. Their brittleness, however, imposes certain limitations in terms of applicability. In that context, novel carbon aerogels with varying degree of flexibility have been developed. These highly porous, light aerogels are characterized by a high surface area and possess pore structures in the micrometer range, allowing for a reversible deformation of the aerogel network. A high ratio of pore size to particle size was found to be crucial for high flexibility. For dynamic microstructural analysis, compression tests were performed in-situ within a scanning electron microscope allowing us to directly visualize the microstructural flexibility of an aerogel. The flexible carbon aerogels were found to withstand between 15% and 30% of uniaxial compression in a reversible fashion. These findings might stimulate further research and new application fields directed towards flexible supercapacitors and batteries.

  15. Purification of carbon nanotubes via selective heating

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, John A.; Wilson, William L.; Jin, Sung Hun; Dunham, Simon N.; Xie, Xu; Islam, Ahmad; Du, Frank; Huang, Yonggang; Song, Jizhou

    2017-11-21

    The present invention provides methods for purifying a layer of carbon nanotubes comprising providing a precursor layer of substantially aligned carbon nanotubes supported by a substrate, wherein the precursor layer comprises a mixture of first carbon nanotubes and second carbon nanotubes; selectively heating the first carbon nanotubes; and separating the first carbon nanotubes from the second carbon nanotubes, thereby generating a purified layer of carbon nanotubes. Devices benefiting from enhanced electrical properties enabled by the purified layer of carbon nanotubes are also described.

  16. Carbon Capture and Storage

    Energy Technology Data Exchange (ETDEWEB)

    Friedmann, S

    2007-10-03

    Carbon capture and sequestration (CCS) is the long-term isolation of carbon dioxide from the atmosphere through physical, chemical, biological, or engineered processes. This includes a range of approaches including soil carbon sequestration (e.g., through no-till farming), terrestrial biomass sequestration (e.g., through planting forests), direct ocean injection of CO{sub 2} either onto the deep seafloor or into the intermediate depths, injection into deep geological formations, or even direct conversion of CO{sub 2} to carbonate minerals. Some of these approaches are considered geoengineering (see the appropriate chapter herein). All are considered in the 2005 special report by the Intergovernmental Panel on Climate Change (IPCC 2005). Of the range of options available, geological carbon sequestration (GCS) appears to be the most actionable and economic option for major greenhouse gas reduction in the next 10-30 years. The basis for this interest includes several factors: (1) The potential capacities are large based on initial estimates. Formal estimates for global storage potential vary substantially, but are likely to be between 800 and 3300 Gt of C (3000 and 10,000 Gt of CO{sub 2}), with significant capacity located reasonably near large point sources of the CO{sub 2}. (2) GCS can begin operations with demonstrated technology. Carbon dioxide has been separated from large point sources for nearly 100 years, and has been injected underground for over 30 years (below). (3) Testing of GCS at intermediate scale is feasible. In the US, Canada, and many industrial countries, large CO{sub 2} sources like power plants and refineries lie near prospective storage sites. These plants could be retrofit today and injection begun (while bearing in mind scientific uncertainties and unknowns). Indeed, some have, and three projects described here provide a great deal of information on the operational needs and field implementation of CCS. Part of this interest comes from several

  17. Ultrahard carbon nanocomposite films

    Energy Technology Data Exchange (ETDEWEB)

    SIEGAL,MICHAEL P.; TALLANT,DAVID R.; PROVENCIO,PAULA P.; OVERMYER,DONALD L.; SIMPSON,REGINA L.; MARTINEZ-MIRANDA,L.J.

    2000-01-27

    Modest thermal annealing to 600 C of diamondlike amorphous-carbon (a-C) films grown at room temperature results in the formation of carbon nanocomposites with hardness similar to diamond. These nanocomposite films consist of nanometer-sized regions of high density a-C embedded in an a-C matrix with a reduced density of 5--10%. The authors report on the evolution of density and bonding topologies as a function of annealing temperature. Despite a decrease in density, film hardness actually increases {approximately} 15% due to the development of the nanocomposite structure.

  18. Lithium in LMC carbon stars

    OpenAIRE

    Hatzidimitriou, D.; Morgan, D. H.; Cannon, R. D.; Croke, B. F. W.

    2003-01-01

    Nineteen carbon stars that show lithium enrichment in their atmospheres have been discovered among a sample of 674 carbon stars in the Large Magellanic Cloud. Six of the Li-rich carbon stars are of J-type, i.e. with strong 13C isotopic features. No super-Li-rich carbon stars were found. The incidence of lithium enrichment among carbon stars in the LMC is much rarer than in the Galaxy, and about five times more frequent among J-type than among N-type carbon stars. The bolometric magnitudes of ...

  19. Authigenic carbonate and the history of the global carbon cycle

    National Research Council Canada - National Science Library

    Schrag, Daniel P; Higgins, John A; Macdonald, Francis A; Johnston, David T

    2013-01-01

    We present a framework for interpreting the carbon isotopic composition of sedimentary rocks, which in turn requires a fundamental reinterpretation of the carbon cycle and redox budgets over Earth's history...

  20. CarbonSat Constellation

    Science.gov (United States)

    Sun, Wei; Tobehn, Carsten; Ernst, Robert; Bovensmann, Heinrich; Buchwitz, Michael; Burrows, John P.; Notholt, John

    1 Carbon dioxide (CO2) and methane (CH4) are the most important manmade greenhouse gases (GHGs) which are driving global climate change. Currently, the CO2 measurements from the ground observing network are still the main sources of information but due to the limited number of measurement stations the coverage is limited. In addition, CO2 monitoring and trading is often based mainly on bottom-up calculations and an independent top down verification is limited due to the lack of global measurement data with local resolution. The first CO2 and CH4 mapping from SCIAMACHY on ENVISAT shows that satellites add important missing global information. Current GHG measurement satellites (GOSAT)are limited either in spatial or temporal resolution and coverage. These systems have to collect data over a year or even longer to produce global regional fluxes products. Conse-quently global, timely, higher spatial resolution and high accuracy measurement are required for: 1. A good understanding of the CO2 and CH4 sources and sinks for reliable climate predic-tion; and 2. Independent and transparent verification of accountable sources and sinks in supporting Kyoto and upcoming protocols The CarbonSat constellation idea comes out the trade off of resolution and swath width during CarbonSat mission definition studies. In response to the urgent need to support the Kyoto and upcoming protocols, a feasibility study has been carried out. The proposed solution is a constellation of five CarbonSat satellites in 614km LTAN 13:00, which is able to provide global, daily CO2 and CH4 measurement everywhere on the Earth with high spatial resolution 2 × 2 km and low uncertainty lt;2ppm (CO2) and lt;8ppb (CH4). The unique global daily measurement capability significantly increases the number of cloud free measurements, which enables more reliable services associated with reduced uncertainty, e.g. to 0.15ppm (CO2) per month in 10km and even more timely products. The CarbonSat Constellation in

  1. Method for production of carbon nanofiber mat or carbon paper

    Science.gov (United States)

    Naskar, Amit K.

    2015-08-04

    Method for the preparation of a non-woven mat or paper made of carbon fibers, the method comprising carbonizing a non-woven mat or paper preform (precursor) comprised of a plurality of bonded sulfonated polyolefin fibers to produce said non-woven mat or paper made of carbon fibers. The preforms and resulting non-woven mat or paper made of carbon fiber, as well as articles and devices containing them, and methods for their use, are also described.

  2. The Kane Experimental Forest carbon inventory: Carbon reporting with FVS

    Science.gov (United States)

    Coeli Hoover; Stephanie Rebain

    2008-01-01

    As the number of state and regional climate change agreements grows, so does the need to assess the carbon implications of planned forest management actions. At the operational level, producing detailed stock estimates for the primary carbon pools becomes time-consuming and cumbersome. Carbon reporting functionality has been fully integrated within the Forest...

  3. Fixation of carbon dioxide into dimethyl carbonate over ...

    Science.gov (United States)

    A titanium-based zeolitic thiophene-benzimidazolate framework has been designed for the direct synthesis of dimethyl carbonate (DMC) from methanol and carbon dioxide. The developed catalyst activates carbon dioxide and delivers over 16% yield of DMC without the use of any dehydrating agent or requirement for azeotropic distillation. Prepared for submission to Nature Scientific reports.

  4. Soil carbon in the Artic and the permafrost carbon feedback

    NARCIS (Netherlands)

    van Huissteden, J.; Dolman, A.J.

    2012-01-01

    Estimates of the Arctic soil carbon pool have more than doubled in size recently. However, it remains very uncertain how much of this carbon will enter the atmosphere as a result of future global warming. We review in this paper recent estimates of the Arctic soil carbon pool, and experimental and

  5. Electron irradiation of carbon dioxide-carbon disulphide ice analog ...

    Indian Academy of Sciences (India)

    Upon electron irradiation the chemical composition was found to have altered and the new products from irradiation were found to be carbonyl sulphide (OCS), sulphur dioxide (SO2), ozone (O3), carbon trioxide (CO3), sulphur trioxide (SO3), carbon subsulphide (C3S2) and carbon monoxide (CO). Results obtained confirm ...

  6. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... 2014 JANUARY 08, 2015 Non-Fire Carbon Monoxide Deaths Associated with the Use of Consumer Products 2011 Annual Estimates View All CO-Related Injury Statistics and Technical Reports Related Links Recalls Safety Education Regulations, Laws & Standards Research & Statistics Business & Manufacturing Small ...

  7. Carbon nanotube solar cells.

    Directory of Open Access Journals (Sweden)

    Colin Klinger

    Full Text Available We present proof-of-concept all-carbon solar cells. They are made of a photoactive side of predominantly semiconducting nanotubes for photoconversion and a counter electrode made of a natural mixture of carbon nanotubes or graphite, connected by a liquid electrolyte through a redox reaction. The cells do not require rare source materials such as In or Pt, nor high-grade semiconductor processing equipment, do not rely on dye for photoconversion and therefore do not bleach, and are easy to fabricate using a spray-paint technique. We observe that cells with a lower concentration of carbon nanotubes on the active semiconducting electrode perform better than cells with a higher concentration of nanotubes. This effect is contrary to the expectation that a larger number of nanotubes would lead to more photoconversion and therefore more power generation. We attribute this to the presence of metallic nanotubes that provide a short for photo-excited electrons, bypassing the load. We demonstrate optimization strategies that improve cell efficiency by orders of magnitude. Once it is possible to make semiconducting-only carbon nanotube films, that may provide the greatest efficiency improvement.

  8. Many Phases of Carbon

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 7; Issue 12. Many Phases of Carbon. B Gopalakrishnan S V Subramanyam. General Article Volume 7 Issue 12 December 2002 pp 10-19. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/007/12/0010-0019 ...

  9. City Carbon Footprint Networks

    Directory of Open Access Journals (Sweden)

    Guangwu Chen

    2016-07-01

    Full Text Available Progressive cities worldwide have demonstrated political leadership by initiating meaningful strategies and actions to tackle climate change. However, the lack of knowledge concerning embodied greenhouse gas (GHG emissions of cities has hampered effective mitigation. We analyse trans-boundary GHG emission transfers between five Australian cities and their trading partners, with embodied emission flows broken down into major economic sectors. We examine intercity carbon footprint (CF networks and disclose a hierarchy of responsibility for emissions between cities and regions. Allocations of emissions to households, businesses and government and the carbon efficiency of expenditure have been analysed to inform mitigation policies. Our findings indicate that final demand in the five largest cities in Australia accounts for more than half of the nation’s CF. City households are responsible for about two thirds of the cities’ CFs; the rest can be attributed to government and business consumption and investment. The city network flows highlight that over half of emissions embodied in imports (EEI to the five cities occur overseas. However, a hierarchy of GHG emissions reveals that overseas regions also outsource emissions to Australian cities such as Perth. We finally discuss the implications of our findings on carbon neutrality, low-carbon city concepts and strategies and allocation of subnational GHG responsibility.

  10. Rapamycin carbonate esters

    OpenAIRE

    Rhodes, A; Sandhu, S S; Onis, J. E; McKendrick, John

    2009-01-01

    Certain embodiments include carbonate esters of rapamycin at position 42 that are synthesized by a lipase catalyzed regio-specific process. These compounds or a pharmaceutically acceptable salt thereof are useful in the treatment of organ and tissue transplant rejection, autoimmune disease, proliferative disorder, restenosis, cancer, or microbial infection.

  11. Closing carbon cycles

    NARCIS (Netherlands)

    Patel, Martin

    1999-01-01

    Fossil fuels are used as raw materials for the manufacture of synthetic organic materials, e.g. plastics, fibres, synthetic rubber, paints, solvents, fertilisers, surfactants, lubricants and bitumen. Since fossil carbon is embodied in these products they may be particularly relevant to climate

  12. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... On Safety Blogs: CO Safety More CO Blogs Research & Statistics JANUARY 07, 2016 Non-Fire Carbon Monoxide ... Website Feedback Connect with Us: Facebook Instagram YouTube Twitter Blog SlideShare GooglePlus Flickr Report an Unsafe Product ...

  13. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... regularly. View Information About CO Alarms Other CO Topics Safety Tips Recalls and News Questions and Answers Charcoal Portable Heaters & Camping Equipment Home Heating Equipment On Safety Blogs: CO Safety More CO Blogs Research & Statistics JANUARY 07, 2016 Non-Fire Carbon Monoxide ...

  14. Many Phases of Carbon

    Indian Academy of Sciences (India)

    carbo' meaning charcoal. Carbon is known as the king of elements owing to its versatility and diversity in all fields, which is unquestionable. It is widely distributed in N a- ture, from molecules of life to matter in outer cosmos. It holds the sixth place ...

  15. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Investigations Associated with Non-Fire Carbon Monoxide from Engine-Driven Generators and Other Engine-Driven Tools, 2004–2014 JANUARY 08, 2015 Non- ... outside of the Federal Government. CPSC does not control this external site or its privacy policy and ...

  16. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Safety Blogs: CO Safety More CO Blogs Research & Statistics JANUARY 07, 2016 Non-Fire Carbon Monoxide Deaths ... left anytime CPSC.gov is the U.S. government's official web portal. Message can be left anytime Website ...

  17. Balancing atmospheric carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Goreau, T.J. (Discovery Bay Marine Laboratory, Univ. of the West Indies (JM))

    1990-01-01

    Rising carbon dioxide and global temperatures are causing increasing worldwide concern, and pressure towards an international law of the atmosphere is rapidly escalating, yet widespread misconceptions about the greenhouse effect's inevitability, time scale, and causes have inhibited effective consensus and action. Observations from Antarctic ice cores, Amazonian rain forests, and Carribean coral reefs suggest that the biological effects of climate change may be more severe than climate models predict. Efforts to limit emissions from fossil-fuel combustion alone are incapable of stabilizing levels of carbon dioxide in the atmosphere. Stabilizing atmospheric carbon dioxide requires coupled measures to balance sources and sinks of the gas, and will only be viable with large-scale investments in increased sustainable productivity on degraded tropical soils, and in long-term research on renewable energy and biomass product development in the developing countries. A mechanism is outlined which directly links fossil-fuel combustion sources of carbon dioxide to removal via increasing biotic productivity and storage. A preliminary cost-benefit analysis suggests that such measures are very affordable, costing far less than inaction. (With 88 refs.).

  18. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... of Consumer Products 2012 Annual Estimates OCTOBER 13, 2015 Incidents, Deaths, and In-Depth Investigations Associated with ... Other Engine-Driven Tools, 2004–2014 JANUARY 08, 2015 Non-Fire Carbon Monoxide Deaths Associated with the ...

  19. Carbon nanotube macroelectronics

    Science.gov (United States)

    Zhang, Jialu

    In this dissertation, I discuss the application of carbon nanotubes in macroelectronis. Due to the extraordinary electrical properties such as high intrinsic carrier mobility and current-carrying capacity, single wall carbon nanotubes are very desirable for thin-film transistor (TFT) applications such as flat panel display, transparent electronics, as well as flexible and stretchable electronics. Compared with other popular channel material for TFTs, namely amorphous silicon, polycrystalline silicon and organic materials, nanotube thin-films have the advantages of low-temperature processing compatibility, transparency, and flexibility, as well as high device performance. In order to demonstrate scalable, practical carbon nanotube macroelectroncis, I have developed a platform to fabricate high-density, uniform separated nanotube based thin-film transistors. In addition, many other essential analysis as well as technology components, such as nanotube film density control, purity and diameter dependent semiconducting nanotube electrical performance study, air-stable n-type transistor fabrication, and CMOS integration platform have also been demonstrated. On the basis of the above achievement, I have further demonstrated various kinds of applications including AMOLED display electronics, PMOS and CMOS logic circuits, flexible and transparent electronics. The dissertation is structured as follows. First, chapter 1 gives a brief introduction to the electronic properties of carbon nanotubes, which serves as the background knowledge for the following chapters. In chapter 2, I will present our approach of fabricating wafer-scale uniform semiconducting carbon nanotube thin-film transistors and demonstrate their application in display electronics and logic circuits. Following that, more detailed information about carbon nanotube thin-film transistor based active matrix organic light-emitting diode (AMOLED) displays is discussed in chapter 3. And in chapter 4, a technology to

  20. Carbon capture and sequestration (CCS)

    Science.gov (United States)

    2009-06-19

    Carbon capture and sequestration (or storage)known as CCShas attracted interest as a : measure for mitigating global climate change because large amounts of carbon dioxide (CO2) : emitted from fossil fuel use in the United States are potentiall...

  1. Carbon Monoxide (CO) Poisoning Prevention

    Science.gov (United States)

    ... this? Submit What's this? Submit Button Past Emails Carbon Monoxide (CO) Poisoning Prevention Language: English (US) Español (Spanish) ... tornadoes), using alternative sources of power can cause carbon monoxide (CO) to build up in a home and ...

  2. Dewatering Peat With Activated Carbon

    Science.gov (United States)

    Rohatgi, N. K.

    1984-01-01

    Proposed process produces enough gas and carbon to sustain itself. In proposed process peat slurry is dewatered to approximately 40 percent moisture content by mixing slurry with activated carbon and filtering with solid/liquid separation techniques.

  3. Carbon emission flow in networks

    National Research Council Canada - National Science Library

    Kang, Chongqing; Zhou, Tianrui; Chen, Qixin; Xu, Qianyao; Xia, Qing; Ji, Zhen

    2012-01-01

    As the human population increases and production expands, energy demand and anthropogenic carbon emission rates have been growing rapidly, and the need to decrease carbon emission levels has drawn increasing attention...

  4. ROE Carbon Storage - Percent Change

    Data.gov (United States)

    U.S. Environmental Protection Agency — This polygon dataset depicts the percentage change in the amount of carbon stored in forests in counties across the United States, based on the difference in carbon...

  5. Where is mantle's carbon?

    Science.gov (United States)

    Oganov, A. R.; Ono, S.; Ma, Y.

    2008-12-01

    Due to the strongly reducing conditions (the presence of metallic iron was suggested both by experiments [1] and theory [2]), diamond was believed to be the main host of carbon through most of the lower mantle [3]. We showed [4] that cementite Fe3C is another good candidate to be the main host of "reduced" carbon in the mantle, reinforcing an earlier hypothesis [5]. The fate of "oxidised" carbon (in subducted slabs) is of particular importance - if carbonates decompose producing fluid CO2, this would have important implications for the chemistry and rheology of the mantle. Knowledge of crystal structures and phase diagrams of carbonates is crucial here. The high-pressure structures of CaCO3 were predicted [6] and subsequently verified by experiments. For MgCO3, Isshiki et al. [7] found a new phase above 110 GPa, and several attempts were made to solve it [8,9]. Here [4], using an evolutionary algorithm for crystal structure prediction [10], we show that there are two post-magnesite phases at mantle-relevant pressure range, one stable at 82-138 GPa, and the other from 138 GPa to ~160 GPa. Both are based on threefold rings of CO4-tetrahedra and are more favourable than all previously proposed structures. We show that through most of the P-T conditions of the mantle, MgCO3 is the major host of oxidized carbon in the Earth. We predict the possibility of CO2 release at the very bottom of the mantle (in SiO2-rich basaltic part of subducted slabs), which could enhance partial melting of rocks and be related to the geodynamical differences between the Earth and Venus. 1.Frost D.J., Liebske C., Langenhorst F., McCammon C.A., Tronnes R.G., Rubie D.C. (2004). Experimental evidence for the existence of iron-rich metal in the Earth's lower mantle. Nature 428, 409-412. 2.Zhang F., Oganov A.R. (2006). Valence and spin states of iron impurities in mantle-forming silicates. Earth Planet. Sci. Lett. 249, 436-443. 3.Luth R.W. (1999). Carbon and carbonates in the mantle. In: Mantle

  6. Carbon. Examples of Property Realization

    OpenAIRE

    I.A. Kossko; A.A. Onoprienko; T.G. Kossko

    2013-01-01

    Examples of realization of carbon properties in formation of section near-surface boundaries defining the mechanism of oxidizing (normal) wear are presented. Synthesis of strengt hening diamond- lonsdaleite -carbene «frame» and graphite with function of solid lubricant on a friction surface in high-desperse carbon environment is reviewed. Prospects of carbon ap placation in implementation of the concept of electronics on one element, and also use of thin-film structures of amorphous carbon – ...

  7. Plasma Processing for Carbon Nanomaterials

    Science.gov (United States)

    Suda, Yoshiyuki; Takikawa, Hirofumi; Tanoue, Hideto

    Plasma is a useful tool to synthesize carbon nano-materials including diamond, fullerene, nanotube and graphene. This review introduces the overview of these carbon nano-materials produced by thermal or non-thermal plasmas and also the authors' work related to plasma-enhanced chemical vapor deposition of carbon nanotubes and its correlation with numerical simulation of CH4/H2 feedstock gas plasmas. The amount of carbon atoms in the CNTs grown and that calculated from simulation showed good agreement.

  8. Advancing Climate and Carbon Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, S

    2004-12-14

    We use a recently developed integrated climate/carbon model to perform breakthrough studies of the climate. Two major studies are carried out--namely the effects of CO{sub 2}-fertilized vegetation on global climate and carbon dynamics, and the effect of climate sensitivity on carbon cycle feedback. We have also begun development of a next-generation climate/carbon modeling capability.

  9. Boron nitride converted carbon fiber

    Science.gov (United States)

    Rousseas, Michael; Mickelson, William; Zettl, Alexander K.

    2016-04-05

    This disclosure provides systems, methods, and apparatus related to boron nitride converted carbon fiber. In one aspect, a method may include the operations of providing boron oxide and carbon fiber, heating the boron oxide to melt the boron oxide and heating the carbon fiber, mixing a nitrogen-containing gas with boron oxide vapor from molten boron oxide, and converting at least a portion of the carbon fiber to boron nitride.

  10. Designing carbon markets, Part 2. Carbon markets in space

    Energy Technology Data Exchange (ETDEWEB)

    Fankhauser, Samuel [Grantham Research Institute and Centre for Climate Change Economics and Policy, London School of Economics, Houghton Street, London WC2A 2AE (United Kingdom); Hepburn, Cameron [Grantham Research Institute, London School of Economics, and Smith School for Enterprise and the Environment, Oxford University, 75 George Street, Oxford OX1 2BQ (United Kingdom)

    2010-08-15

    This paper analyses the design of carbon markets in space (i.e., geographically). It is part of a twin set of papers that, starting from first principles, ask what an optimal global carbon market would look like by around 2030. Our focus is on firm-level cap-and-trade systems, although much of what we say would also apply to government-level trading and carbon offset schemes. We examine the first principles of spatial design to maximise flexibility and to minimise costs, including key design issues in linking national and regional carbon markets together to create a global carbon market. (author)

  11. Designing carbon markets, Part II: Carbon markets in space

    Energy Technology Data Exchange (ETDEWEB)

    Fankhauser, Samuel, E-mail: s.fankhauser@lse.ac.u [Grantham Research Institute and Centre for Climate Change Economics and Policy, London School of Economics, Houghton Street, London WC2A 2AE (United Kingdom); Hepburn, Cameron, E-mail: cameron.hepburn@economics.ox.ac.u [Grantham Research Institute, London School of Economics, and Smith School for Enterprise and the Environment, Oxford University, 75 George Street, Oxford OX1 2BQ (United Kingdom)

    2010-08-15

    This paper analyses the design of carbon markets in space (i.e., geographically). It is part of a twin set of papers that, starting from first principles, ask what an optimal global carbon market would look like by around 2030. Our focus is on firm-level cap-and-trade systems, although much of what we say would also apply to government-level trading and carbon offset schemes. We examine the 'first principles' of spatial design to maximise flexibility and to minimise costs, including key design issues in linking national and regional carbon markets together to create a global carbon market.

  12. The Structures & Properties of Carbon

    Science.gov (United States)

    Castellini, Olivia M.; Lisensky, George C.; Ehrlich, Jennifer; Zenner, Greta M.; Crone, Wendy C.

    2006-01-01

    The four main forms of carbon--diamond, graphite, buckyballs, and carbon nanotubes (CNTs)--are an excellent vehicle for teaching fundamental principles of chemical bonding, material structure, and properties. Carbon atoms form a variety of structures that are intrinsically connected to the properties they exhibit. Educators can take advantage of…

  13. Low Carbon Development of Hainan

    Science.gov (United States)

    Yi, Feng; Kun, Zhang

    With the construction of Hainan international tourism island rising to a national strategy level, the green growth pattern based on low carbon objectives will become a significant part in the development of Hainan's economy. In this paper, low carbon electric power system and differentiation service will be discussed, and some opinions were brought up to have a good impact on Hainan's low carbon development.

  14. Carbon Fiber Risk Analysis. [conference

    Science.gov (United States)

    1979-01-01

    The scope and status of the effort to assess the risks associated with the accidental release of carbon/graphite fibers from civil aircraft is presented. Vulnerability of electrical and electronic equipment to carbon fibers, dispersal of carbon fibers, effectiveness of filtering systems, impact of fiber induced failures, and risk methodology are among the topics covered.

  15. Carbon nanotube junctions and devices

    NARCIS (Netherlands)

    Postma, H.W.Ch.

    2001-01-01

    In this thesis Postma presents transport experiments performed on individual single-wall carbon nanotubes. Carbon nanotubes are molecules entirely made of carbon atoms. The electronic properties are determined by the exact symmetry of the nanotube lattice, resulting in either metallic or

  16. Carbon dioxide as a carbon source in organic transformation: carbon-carbon bond forming reactions by transition-metal catalysts.

    OpenAIRE

    Tsuji, Yasushi; Fujihara, Tetsuaki

    2012-01-01

    Recent carbon-carbon bond forming reactions of carbon dioxide with alkenes, alkynes, dienes, aryl zinc compounds, aryl boronic esters, aryl halides, and arenes having acidic C-H bonds are reviewed in which transition-metal catalysts play an important role.

  17. Erosion of soil organic carbon: implications for carbon sequestration

    Science.gov (United States)

    Van Oost, Kristof; Van Hemelryck, Hendrik; Harden, Jennifer W.; McPherson, B.J.; Sundquist, E.T.

    2009-01-01

    Agricultural activities have substantially increased rates of soil erosion and deposition, and these processes have a significant impact on carbon (C) mineralization and burial. Here, we present a synthesis of erosion effects on carbon dynamics and discuss the implications of soil erosion for carbon sequestration strategies. We demonstrate that for a range of data-based parameters from the literature, soil erosion results in increased C storage onto land, an effect that is heterogeneous on the landscape and is variable on various timescales. We argue that the magnitude of the erosion term and soil carbon residence time, both strongly influenced by soil management, largely control the strength of the erosion-induced sink. In order to evaluate fully the effects of soil management strategies that promote carbon sequestration, a full carbon account must be made that considers the impact of erosion-enhanced disequilibrium between carbon inputs and decomposition, including effects on net primary productivity and decomposition rates.

  18. Carbon composites composites with carbon fibers, nanofibers, and nanotubes

    CERN Document Server

    Chung, Deborah D L

    2017-01-01

    Carbon Composites: Composites with Carbon Fibers, Nanofibers, and Nanotubes, Second Edition, provides the reader with information on a wide range of carbon fiber composites, including polymer-matrix, metal-matrix, carbon-matrix, ceramic-matrix and cement-matrix composites. In contrast to other books on composites, this work emphasizes materials rather than mechanics. This emphasis reflects the key role of materials science and engineering in the development of composite materials. The applications focus of the book covers both the developing range of structural applications for carbon fiber composites, including military and civil aircraft, automobiles and construction, and non-structural applications, including electromagnetic shielding, sensing/monitoring, vibration damping, energy storage, energy generation, and deicing. In addition to these new application areas, new material in this updated edition includes coverage of cement-matrix composites, carbon nanofibers, carbon matrix precursors, fiber surface ...

  19. Carbon dioxide dangers demonstration model

    Science.gov (United States)

    Venezky, Dina; Wessells, Stephen

    2010-01-01

    Carbon dioxide is a dangerous volcanic gas. When carbon dioxide seeps from the ground, it normally mixes with the air and dissipates rapidly. However, because carbon dioxide gas is heavier than air, it can collect in snowbanks, depressions, and poorly ventilated enclosures posing a potential danger to people and other living things. In this experiment we show how carbon dioxide gas displaces oxygen as it collects in low-lying areas. When carbon dioxide, created by mixing vinegar and baking soda, is added to a bowl with candles of different heights, the flames are extinguished as if by magic.

  20. Elastic Moduli of Carbon Nanohorns

    Directory of Open Access Journals (Sweden)

    Dinesh Kumar

    2011-01-01

    Full Text Available Carbon nanotube is a special case of carbon nanohorns or carbon nanocones with zero apex angle. Research into carbon nanohorns started almost at the same time as the discovery of nanotubes in 1991. Most researchers focused on the investigation of nanotubes, and the exploration of nanohorns attracted little attention. To model the carbon nanohorns, we make use of a more reliable second-generation reactive empirical bond-order potential by Brenner and coworkers. We investigate the elastic moduli and conclude that these nanohorns are equally strong and require in-depth investigation. The values of Young's and Shear moduli decrease with apex angle.

  1. Designing rigid carbon foams

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sora; Ahn, Jeung Sun; Kwon, Young-Kyun; Tomanek, David [Department of Physics and Research Institute for Basic Sciences, Kyung Hee University, Seoul, 130-701 (Korea, Republic of); Kittimanapun, Kritsada, E-mail: ykkwon@khu.ac.k, E-mail: tomanek@pa.msu.ed [Physics and Astronomy Department, Michigan State University, East Lansing, MI 48824-2320 (United States)

    2010-08-25

    We use ab initio density functional calculations to study the stability, elastic properties and electronic structure of sp{sup 2} carbon minimal surfaces with negative Gaussian curvature, called schwarzites. We focus on two systems with cubic unit cells containing 152 and 200 carbon atoms, which are metallic and very rigid. The porous schwarzite structure allows for efficient and reversible doping by electron donors and acceptors, making it a promising candidate for the next generation of alkali ion batteries. We identify schwarzite structures that act as arrays of interconnected spin quantum dots or become magnetic when doped. We introduce two interpenetrating schwarzite structures that may find their use as the ultimate super-capacitor.

  2. Properties of amorphous carbon

    CERN Document Server

    2003-01-01

    Amorphous carbon has a wide range of properties that are primarily controlled by the different bond hydridisations possible in such materials. This allows for the growth of an extensive range of thin films that can be tailored for specific applications. Films can range from those with high transparency and are hard diamond-like, through to those which are opaque, soft and graphitic-like. Films with a high degree of sp3 bonding giving the diamond-like properties are used widely by industry for hard coatings. Application areas including field emission cathodes, MEMS, electronic devices, medical and optical coatings are now close to market. Experts in amorphous carbon have been drawn together to produce this comprehensive commentary on the current state and future prospects of this highly functional material.

  3. Carbon nanotube biosensors

    Science.gov (United States)

    Tîlmaciu, Carmen-Mihaela; Morris, May C.

    2015-01-01

    Nanomaterials possess unique features which make them particularly attractive for biosensing applications. In particular, carbon nanotubes (CNTs) can serve as scaffolds for immobilization of biomolecules at their surface, and combine several exceptional physical, chemical, electrical, and optical characteristics properties which make them one of the best suited materials for the transduction of signals associated with the recognition of analytes, metabolites, or disease biomarkers. Here we provide a comprehensive review on these carbon nanostructures, in which we describe their structural and physical properties, functionalization and cellular uptake, biocompatibility, and toxicity issues. We further review historical developments in the field of biosensors, and describe the different types of biosensors which have been developed over time, with specific focus on CNT-conjugates engineered for biosensing applications, and in particular detection of cancer biomarkers. PMID:26579509

  4. Carbon Lorenz Curves

    Energy Technology Data Exchange (ETDEWEB)

    Groot, L. [Utrecht University, Utrecht School of Economics, Janskerkhof 12, 3512 BL Utrecht (Netherlands)

    2008-11-15

    The purpose of this paper is twofold. First, it exhibits that standard tools in the measurement of income inequality, such as the Lorenz curve and the Gini-index, can successfully be applied to the issues of inequality measurement of carbon emissions and the equity of abatement policies across countries. These tools allow policy-makers and the general public to grasp at a single glance the impact of conventional distribution rules such as equal caps or grandfathering, or more sophisticated ones, on the distribution of greenhouse gas emissions. Second, using the Samuelson rule for the optimal provision of a public good, the Pareto-optimal distribution of carbon emissions is compared with the distribution that follows if countries follow Nash-Cournot abatement strategies. It is shown that the Pareto-optimal distribution under the Samuelson rule can be approximated by the equal cap division, represented by the diagonal in the Lorenz curve diagram.

  5. Carbon Lorenz curves

    Energy Technology Data Exchange (ETDEWEB)

    Groot, Loek [Utrecht University School of Economics (USE), Faculty of Law, Economics and Governance, Janskerkhof 12, 3512 BL Utrecht (Netherlands)

    2010-01-15

    The purpose of this paper is twofold. First, it exhibits that standard tools in the measurement of income inequality, such as the Lorenz curve and the Gini-index, can successfully be applied to the issues of inequality measurement of carbon emissions and the equity of abatement policies across countries. These tools allow policy-makers and the general public to grasp at a single glance the impact of conventional distribution rules such as equal caps or grandfathering, or more sophisticated ones, on the distribution of greenhouse gas emissions. Second, using the Samuelson rule for the optimal provision of a public good, the Pareto-optimal distribution of carbon emissions is compared with the distribution that follows if countries follow Nash-Cournot abatement strategies. It is shown that the Pareto-optimal distribution under the Samuelson rule can be approximated by the equal cap division, represented by the diagonal in the Lorenz curve diagram. (author)

  6. Carbon Fiber Composites

    Science.gov (United States)

    1997-01-01

    HyComp(R), Inc. development a line of high temperature carbon fiber composite products to solve wear problems in the harsh environment of steel and aluminum mills. WearComp(R), self-lubricating composite wear liners and bushings, combines carbon graphite fibers with a polyimide binder. The binder, in conjunction with the fibers, provides the slippery surface, one that demands no lubrication, yet wears at a very slow rate. WearComp(R) typically lasts six to ten times longer than aluminum bronze. Unlike bronze, WearComp polishes the same surface and imparts a self-lube film for years of service. It is designed for continuous operation at temperatures of 550 degrees Fahrenheit and can operate under high compressive loads.

  7. Carbon Nanotube Biosensors

    Science.gov (United States)

    Tilmaciu, Carmen-Mihaela; Morris, May

    2015-10-01

    Nanomaterials possess unique features which make them particularly attractive for biosensing applications. In particular Carbon Nanotubes (CNTs) can serve as scaffolds for immobilization of biomolecules at their surface, and combine several exceptional physical, chemical, electrical and optical characteristics properties which make them one of the best suited materials for the transduction of signals associated with the recognition of analytes, metabolites or disease biomarkers. Here we provide a comprehensive review on these carbon nanostructures, in which we will describe their structural and physical properties, discuss functionalization and cellular uptake, biocompatibility and toxicity issues. We further review historical developments in the field of biosensors, and describe the different types of biosensors which have been developed over time, with specific focus on CNT-conjugates engineered for biosensing applications, and in particular detection of cancer biomarkers.

  8. Carbon cycle makeover

    DEFF Research Database (Denmark)

    Canfield, Donald Eugene; Kump, Lee R.

    2013-01-01

    In 1845, the French chemist and mining engineer Jacques-Joseph Ebelman figured out why Earth's atmosphere contains oxygen (1). Oxygen is produced by plants during photosynthesis, but almost all of this oxygen is used again in respiration. Ebelman reasoned that small amounts of organic matter rema...... geochemical cycle. But Earth is an old planet, and oxygen levels have changed through time (2). On page 540 of this issue, Schrag et al. (3) challenge the most commonly used geochemical approach to assess long-term changes in the coupled oxygen and carbon cycles....... remaining in sediments after respiration leave a residual of oxygen in the atmosphere. The source of oxygen to the atmosphere represented by organic matter burial is balanced by oxygen sinks associated with rock weathering and chemical reaction with volcanic gases. This is the long-term carbon and oxygen...

  9. Carbon Nanotube Biosensors

    Directory of Open Access Journals (Sweden)

    Carmen-Mihaela eTilmaciu

    2015-10-01

    Full Text Available Nanomaterials possess unique features which make them particularly attractive for biosensing applications. In particular Carbon Nanotubes (CNTs can serve as scaffolds for immobilization of biomolecules at their surface, and combine several exceptional physical, chemical, electrical and optical characteristics properties which make them one of the best suited materials for the transduction of signals associated with the recognition of analytes, metabolites or disease biomarkers. Here we provide a comprehensive review on these carbon nanostructures, in which we will describe their structural and physical properties, discuss functionalization and cellular uptake, biocompatibility and toxicity issues. We further review historical developments in the field of biosensors, and describe the different types of biosensors which have been developed over time, with specific focus on CNT-conjugates engineered for biosensing applications, and in particular detection of cancer biomarkers.

  10. Magnetism in carbon nanostructures

    CERN Document Server

    Hagelberg, Frank

    2017-01-01

    Magnetism in carbon nanostructures is a rapidly expanding field of current materials science. Its progress is driven by the wide range of applications for magnetic carbon nanosystems, including transmission elements in spintronics, building blocks of cutting-edge nanobiotechnology, and qubits in quantum computing. These systems also provide novel paradigms for basic phenomena of quantum physics, and are thus of great interest for fundamental research. This comprehensive survey emphasizes both the fundamental nature of the field, and its groundbreaking nanotechnological applications, providing a one-stop reference for both the principles and the practice of this emerging area. With equal relevance to physics, chemistry, engineering and materials science, senior undergraduate and graduate students in any of these subjects, as well as all those interested in novel nanomaterials, will gain an in-depth understanding of the field from this concise and self-contained volume.

  11. Low carbon development. Key issues

    Energy Technology Data Exchange (ETDEWEB)

    Urban, Frauke; Nordensvaard, Johan (eds.)

    2013-03-07

    This comprehensive textbook addresses the interface between international development and climate change in a carbon constrained world. It discusses the key conceptual, empirical and policy-related issues of low carbon development and takes an international and interdisciplinary approach to the subject by drawing on insights from across the natural sciences and social sciences whilst embedding the discussion in a global context. The first part explores the concept of low carbon development and explains the need for low carbon development in a carbon constrained world. The book then discusses the key issues of socio-economic, political and technological nature for low carbon development, exploring topics such as the political economy, social justice, financing and carbon markets, and technologies and innovation for low carbon development. This is followed by key issues for low carbon development in policy and practice, which is presented based on cross-cutting issues such as low carbon energy, forestry, agriculture and transportation. Afterwards, practical case studies are discussed from low carbon development in low income countries in Africa, middle income countries in Asia and Latin America and high income countries in Europe and North America.

  12. Carbon Materials Research

    Science.gov (United States)

    2006-08-01

    wt% polyvinyl alcohol (Airvol 2005 PVA,Air Products andChemicals,Allentown, PA). The mixture was uniaxially pressed into bars (11 mm long × 9.9 mm...process. First, carbon fibers, which carry the mechanical load, are woven, braided, felted, or filament wound into a preform which has the shape of the... filaments , injection of brake preforms, and in fab- rication of anode materials for lithium ion batteries. The principle behind the impregnation with in

  13. Carbon Nanotubes for Supercapacitor

    OpenAIRE

    Li Jianyi; Pan Hui; Feng YuanPing

    2010-01-01

    Abstract As an electrical energy storage device, supercapacitor finds attractive applications in consumer electronic products and alternative power source due to its higher energy density, fast discharge/charge time, low level of heating, safety, long-term operation stability, and no disposable parts. This work reviews the recent development of supercapacitor based on carbon nanotubes (CNTs) and their composites. The purpose is to give a comprehensive understanding of the advantages and disad...

  14. Brominated graphitized carbon fibers

    Science.gov (United States)

    Hung, Ching-Cheh (Inventor)

    1991-01-01

    Low cost, high break elongation graphitized carbon fibers having low degree of graphitization are inert to bromine at room or higher temperatures, but are brominated at -7 to 20 C, and then debrominated at ambient. Repetition of this bromination-debromination process can bring the bromine content to 18 percent. Electrical conductivity of the brominated fibers is three times of the before-bromination value.

  15. 148. Carbon Nanotubes

    OpenAIRE

    Hedmer, Maria; Kåredal, Monica; Gustavsson, Per; Rissler, Jenny

    2013-01-01

    Carbon nanotubes (CNTs) can be seen as graphene sheets rolled to form cylinders. CNTs may be categorised as single- (SWCNT) or multi-walled (MWCNT). Due to the small size, the number of particles as well as the surface area per mass unit is extremely high. CNTs are highly diverse, differing with respect to e.g., diameter, length, chiral angles, chemical functionalisation, purity, stiffness and bulk density. Today, CNTs are utilised primarily for the reinforcement of composite polymers, but th...

  16. Interfaces of Propylene Carbonate

    OpenAIRE

    You, Xinli; Chaudhari, Mangesh I.; Pratt, Lawrence R.; Pesika, Noshir; Aritakula, Kalika M.; Rick, Steven W.

    2012-01-01

    Propylene carbonate (PC) wets graphite with a contact angle of 31 deg at ambient conditions. Molecular dynamics simulations agree with this contact angle after 40% reduction of the strength of graphite-C atom Lennard-Jones interactions with the solvent, relative to the models used initially. A simulated nano-scale PC droplet on graphite displays a pronounced layering tendency and an Aztex pyramid structure for the droplet. Extrapolation of the computed tensions of PC liquid-vapor interface es...

  17. Carbon Structure Hazard Control

    Science.gov (United States)

    Yoder, Tommy; Greene, Ben; Porter, Alan

    2015-01-01

    Carbon composite structures are widely used in virtually all advanced technology industries for a multitude of applications. The high strength-to-weight ratio and resistance to aggressive service environments make them highly desirable. Automotive, aerospace, and petroleum industries extensively use, and will continue to use, this enabling technology. As a result of this broad range of use, field and test personnel are increasingly exposed to hazards associated with these structures. No single published document exists to address the hazards and make recommendations for the hazard controls required for the different exposure possibilities from damaged structures including airborne fibers, fly, and dust. The potential for personnel exposure varies depending on the application or manipulation of the structure. The effect of exposure to carbon hazards is not limited to personnel, protection of electronics and mechanical equipment must be considered as well. The various exposure opportunities defined in this document include pre-manufacturing fly and dust, the cured structure, manufacturing/machining, post-event cleanup, and post-event test and/or evaluation. Hazard control is defined as it is applicable or applied for the specific exposure opportunity. The carbon exposure hazard includes fly, dust, fiber (cured/uncured), and matrix vapor/thermal decomposition products. By using the recommendations in this document, a high level of confidence can be assured for the protection of personnel and equipment.

  18. Spectroelectrochemistry of carbon nanostructures.

    Science.gov (United States)

    Kavan, Ladislav; Dunsch, Lothar

    2007-05-14

    This review is focused on charge-transfer reactions at carbon nanotubes and fullerenes. The spectroelectrochemistry of fullerenes deals with the spin states of fullerenes, the role of mono-anions and the reactivity of higher charged states in C60. The optical (Vis-NIR) spectroelectrochemistry of single-walled carbon nanotubes (SWNTs) follows changes in the allowed optical transitions among the Van Hove singularities. The Raman spectroelectrochemistry of SWNT benefits from strong resonance enhancement of the Raman scattering. Here, both semiconducting and metallic SWNTs are analyzed using the radial breathing mode (RBM) and G-modes as well as the second order (D, G') and intermediate frequency modes. Raman spectroelectrochemistry of SWNT allows the addressing of index-identified tubes and even single isolated nanotubes. Optical and Raman spectroelectrochemistry of fullerene peapods, C60@SWNT and C70@SWNT indicates effective shielding of the intratubular fullerene (peas). The most striking effect in the spectroelectrochemistry of peapods is the so-called "anodic Raman enhancement" of intratubular C60. Double-walled carbon nanotubes (DWNTs) give a specific spectroscopic response in Vis-NIR spectroelectrochemistry for the inner and the outer tube. They are better distinguishable by Raman spectroelectrochemistry which allows a precise tracing of the specific doping response of outer/inner tubes.

  19. Securing tropical forest carbon

    DEFF Research Database (Denmark)

    Scharlemann, Jörn P. W.; Kapos, Valerie; Campbell, Alison

    2010-01-01

    Forest loss and degradation in the tropics contribute 6-17% of all greenhouse gas emissions. Protected areas cover 217.2 million ha (19.6%) of the world's humid tropical forests and contain c. 70.3 petagrams of carbon (Pg C) in biomass and soil to 1 m depth. Between 2000 and 2005, we estimate...... that 1.75 million ha of forest were lost from protected areas in humid tropical forests, causing the emission of 0.25-0.33 Pg C. Protected areas lost about half as much carbon as the same area of unprotected forest. We estimate that the reduction of these carbon emissions from ongoing deforestation...... in protected sites in humid tropical forests could be valued at USD 6,200-7,400 million depending on the land use after clearance. This is >1.5 times the estimated spending on protected area management in these regions. Improving management of protected areas to retain forest cover better may be an important...

  20. Hydropower's Biogenic Carbon Footprint.

    Science.gov (United States)

    Scherer, Laura; Pfister, Stephan

    2016-01-01

    Global warming is accelerating and the world urgently needs a shift to clean and renewable energy. Hydropower is currently the largest renewable source of electricity, but its contribution to climate change mitigation is not yet fully understood. Hydroelectric reservoirs are a source of biogenic greenhouse gases and in individual cases can reach the same emission rates as thermal power plants. Little is known about the severity of their emissions at the global scale. Here we show that the carbon footprint of hydropower is far higher than previously assumed, with a global average of 173 kg CO2 and 2.95 kg CH4 emitted per MWh of electricity produced. This results in a combined average carbon footprint of 273 kg CO2e/MWh when using the global warming potential over a time horizon of 100 years (GWP100). Nonetheless, this is still below that of fossil energy sources without the use of carbon capture and sequestration technologies. We identified the dams most promising for capturing methane for use as alternative energy source. The spread among the ~1500 hydropower plants analysed in this study is large and highlights the importance of case-by-case examinations.

  1. Hydropower's Biogenic Carbon Footprint.

    Directory of Open Access Journals (Sweden)

    Laura Scherer

    Full Text Available Global warming is accelerating and the world urgently needs a shift to clean and renewable energy. Hydropower is currently the largest renewable source of electricity, but its contribution to climate change mitigation is not yet fully understood. Hydroelectric reservoirs are a source of biogenic greenhouse gases and in individual cases can reach the same emission rates as thermal power plants. Little is known about the severity of their emissions at the global scale. Here we show that the carbon footprint of hydropower is far higher than previously assumed, with a global average of 173 kg CO2 and 2.95 kg CH4 emitted per MWh of electricity produced. This results in a combined average carbon footprint of 273 kg CO2e/MWh when using the global warming potential over a time horizon of 100 years (GWP100. Nonetheless, this is still below that of fossil energy sources without the use of carbon capture and sequestration technologies. We identified the dams most promising for capturing methane for use as alternative energy source. The spread among the ~1500 hydropower plants analysed in this study is large and highlights the importance of case-by-case examinations.

  2. Composition of carbonization residues

    Energy Technology Data Exchange (ETDEWEB)

    Hupfer; Leonhardt

    1943-11-30

    This report gave a record of the composition of several samples of residues from carbonization of various hydrogenation residue from processing some type of coal or tar in the Bergius process. These included Silesian bituminous coal processed at 600 atm. with iron catalyst, in one case to produce gasoline and middle oil and in another case to produce heavy oil excess, Scholven coal processed at 250 atm. with tin oxalate and chlorine catalyst, Bruex tar processed in a 10-liter oven using iron catalyst, and a pitch mixture from Welheim processed in a 10-liter over using iron catalyst. The values gathered were compared with a few corresponding values estimated for Boehlen tar and Gelsenberg coal based on several assumptions outlined in the report. The data recorded included percentage of ash in the dry residue and percentage of carbon, hydrogen, oxygen, nitrogen, chlorine, total sulfur, and volatile sulfur. The percentage of ash varied from 21.43% in the case of Bruex tar to 53.15% in the case of one of the Silesian coals. Percentage of carbon varied from 44.0% in the case of Scholven coal to 78.03% in the case of Bruex tar. Percentage of total sulfur varied from 2.28% for Bruex tar to a recorded 5.65% for one of the Silesian coals and an estimated 6% for Boehlen tar. 1 table.

  3. Interfaces of propylene carbonate

    Science.gov (United States)

    You, Xinli; Chaudhari, Mangesh I.; Pratt, Lawrence R.; Pesika, Noshir; Aritakula, Kalika M.; Rick, Steven W.

    2013-03-01

    Propylene carbonate (PC) wets graphite with a contact angle of 31° at ambient conditions. Molecular dynamics simulations agree with this contact angle after 40% reduction of the strength of graphite-C atom Lennard-Jones interactions with the solvent, relative to the models used initially. A simulated nano-scale PC droplet on graphite displays a pronounced layering tendency and an Aztex pyramid structure for the droplet. Extrapolation of the computed tensions of PC liquid-vapor interface estimates the critical temperature of PC accurately to about 3%. PC molecules lie flat on the PC liquid-vapor surface and tend to project the propyl carbon toward the vapor phase. For close PC neighbors in liquid PC, an important packing motif stacks carbonate planes with the outer oxygen of one molecule snuggled into the positively charged propyl end of another molecule so that neighboring molecule dipole moments are approximately antiparallel. The calculated thermal expansion coefficient and the dielectric constants for liquid PC agree well with experiment. The distribution of PC molecule binding energies is closely Gaussian. Evaluation of the density of the coexisting vapor then permits estimation of the packing contribution to the PC chemical potential and that contribution is about two thirds of the magnitude of the contributions due to attractive interactions, with opposite sign.

  4. Imaging of Carbon Translocation to Fruit Using Carbon-11-Labeled Carbon Dioxide and Positron Emission Tomography

    Science.gov (United States)

    Kawachi, Naoki; Kikuchi, Kaori; Suzui, Nobuo; Ishii, Satomi; Fujimaki, Shu; Ishioka, Noriko S.; Watabe, Hiroshi

    2011-04-01

    Carbon kinetics into the fruit is an agricultural issue on the growth and development of the sink organs to be harvested. Particularly, photoassimilate translocation and distribution are important topics for understanding the mechanism. In the present work, carbon-11 (11C) labeled photoassimilate translocation into fruits of tomato has been imaged using carbon-11-labeled carbon dioxide and the positron emission tomography (PET). Dynamice PET data of gradual increasing of 11C activity and its distribution is acquired quantitatively in intact plant body. This indicates that the 3-D photoassimilate translocation into the fruits is imaged successfully and carbon kinetics is analyzable to understand the plant physiology and nutrition.

  5. Limits on carbon sequestration in arid blue carbon ecosystems.

    Science.gov (United States)

    Schile, Lisa M; Kauffman, J Boone; Crooks, Stephen; Fourqurean, James W; Glavan, Jane; Megonigal, J Patrick

    2017-04-01

    Coastal ecosystems produce and sequester significant amounts of carbon ("blue carbon"), which has been well documented in humid and semi-humid regions of temperate and tropical climates but less so in arid regions where mangroves, marshes, and seagrasses exist near the limit of their tolerance for extreme temperature and salinity. To better understand these unique systems, we measured whole-ecosystem carbon stocks in 58 sites across the United Arab Emirates (UAE) in natural and planted mangroves, salt marshes, seagrass beds, microbial mats, and coastal sabkha (inter- and supratidal unvegetated salt flats). Natural mangroves held significantly more carbon in above- and belowground biomass than other vegetated ecosystems. Planted mangrove carbon stocks increased with age, but there were large differences for sites of similar age. Soil carbon varied widely across sites (2-367 Mg C/ha), with ecosystem averages that ranged from 49 to 156 Mg C/ha. For the first time, microbial mats were documented to contain soil carbon pools comparable to vascular plant-dominated ecosystems, and could arguably be recognized as a unique blue carbon ecosystem. Total ecosystem carbon stocks ranged widely from 2 to 515 Mg C/ha (seagrass bed and mangrove, respectively). Seagrass beds had the lowest carbon stock per unit area, but the largest stock per total area due to their large spatial coverage. Compared to similar ecosystems globally, mangroves and marshes in the UAE have lower plant and soil carbon stocks; however, the difference in soil stocks is far larger than with plant stocks. This incongruent difference between stocks is likely due to poor carbon preservation under conditions of weakly reduced soils (200-350 mV), coarse-grained sediments, and active shoreline migration. This work represents the first attempt to produce a country-wide coastal ecosystem carbon accounting using a uniform sampling protocol, and was motivated by specific policy goals identified by the Abu Dhabi Global

  6. Magneto-carbonization method for production of carbon fiber, and high performance carbon fibers made thereby

    Energy Technology Data Exchange (ETDEWEB)

    Naskar, Amit K.; Ozcan, Soydan; Eberle, Claude C.; Abdallah, Mohamed Gabr; Mackiewicz, Ludtka Gail; Ludtka, Gerard Michael; Paulauskas, Felix Leonard; Rivard, John Daniel Kennedy

    2017-08-08

    Method for the preparation of carbon fiber from fiber precursor, wherein the fiber precursor is subjected to a magnetic field of at least 3 Tesla during a carbonization process. The carbonization process is generally conducted at a temperature of at least 400.degree. C. and less than 2200.degree. C., wherein, in particular embodiments, the carbonization process includes a low temperature carbonization step conducted at a temperature of at least or above 400.degree. C. or 500.degree. C. and less than or up to 1000.degree. C., 1100.degree. C., or 1200.degree. C., followed by a high temperature carbonization step conducted at a temperature of at least or above 1200.degree. C. In particular embodiments, particularly in the case of a polyacrylonitrile (PAN) fiber precursor, the resulting carbon fiber may possess a minimum tensile strength of at least 600 ksi, a tensile modulus of at least 30 Msi, and an ultimate elongation of at least 1.5%.

  7. [Forest carbon cycle model: a review].

    Science.gov (United States)

    Wang, Ping

    2009-06-01

    Forest carbon cycle is one of the important items in the research of terrestrial carbon cycle, while carbon cycle model is an important means in studying the carbon cycle mechanisms of forest ecosystem and in estimating carbon fluxes. Based on the sum-up of main carbon cycle models, this paper classified the forest carbon cycle models into two categories, i.e., patch scale forest carbon cycle models and regional scale terrestrial carbon cycle models, with their features commented. The future development trend in the research of forest carbon cycle models in China was discussed.

  8. Natural Carbonation of Peridotite and Applications for Carbon Storage

    Science.gov (United States)

    Streit, E.; Kelemen, P.; Matter, J.

    2009-05-01

    Natural carbonation of peridotite in the Samail Ophiolite of Oman is surprisingly rapid and could be further enhanced to provide a safe, permanent method of CO2 storage through in situ formation of carbonate minerals. Carbonate veins form by low-temperature reaction between peridotite and groundwater in a shallow weathering horizon. Reaction with peridotite drives up the pH of the water, and extensive travertine terraces form where this groundwater emerges at the surface in alkaline springs. The potential sink for CO2 in peridotite is enormous: adding 1wt% CO2 to the peridotite in Oman could consume 1/4 of all atmospheric carbon, and several peridotite bodies of comparable size exist throughout the world. Thus carbonation rate and cost, not reservoir size, are the limiting factors on the usefulness of in situ mineral carbonation of peridotite for carbon storage. The carbonate veins in Oman are much younger than previously believed, yielding average 14C ages of 28,000 years. Age data plus estimated volumes of carbonate veins and terraces suggest 10,000 to 100,000 tons per year of CO2 are consumed by these peridotite weathering reactions in Oman. This rate can be enhanced by drilling, hydraulic fracture, injecting CO2-rich fluid, and increasing reaction temperature. Drilling and hydraulic fracture can increase volume of peridotite available for reaction. Additional fracture may occur due to the solid volume increase of the carbonation reaction, and field observations suggest that such reaction-assisted fracture may be responsible for hierarchical carbonate vein networks in peridotite. Natural carbonation of peridotite in Oman occurs at low pCO2, resulting in partial carbonation of peridotite, forming magnesite and serpentine. Raising pCO2 increases carbonation efficiency, forming of magnesite + talc, or at complete carbonation, magnesite + quartz, allowing ˜30wt% CO2 to be added to the peridotite. Increasing the temperature to 185°C can improve the reaction rate by

  9. Sensitivity of carbon sequestration costs to soil carbon rates.

    Science.gov (United States)

    Antle, J; Capalbo, S; Mooney, S; Elliott, E T; Paustian, K H

    2002-01-01

    Modifying current agricultural management practices as a means of sequestering carbon has been shown to be a relatively low cost way to offset greenhouse gas emissions. In this paper we examine the sensitivity of the estimates of the amount of soil carbon sequestered and the implied costs of sequestering a tonne of carbon to changes in the rates of soil carbon sequestered for alternative production practices. An application is made to the dryland grain production systems of the US Northern Plains where the marginal costs of soil C range from $20 to $100 per MT. We show that the resulting changes in the marginal costs quantities of C sequestered are not a monotonic transformation of the changes in the soil carbon rates. These results underscore the importance of using a linked economic and biophysical simulation model to assess the economic potential for sequestering carbon in agricultural soils.

  10. The Toxicology of Carbon Nanotubes

    Science.gov (United States)

    Donaldson, Ken; Poland, Craig; Duffin, Rodger; Bonner, James

    2012-06-01

    1. Carbon nanotube structure, synthesis and applications C. Singh and W. Song; 2. The aerodynamic behaviour and pulmonary deposition of carbon nanotubes A. Buckley, R. Smith and R Maynard; 3. Utilising the concept of the biologically effective dose to define the particle and fibre hazards of carbon nanotubes K. Donaldson, R. Duffin, F. Murphy and C. Poland; 4. CNT, biopersistence and the fibre paradigm D. Warheit and M. DeLorme; 5. Length-dependent retention of fibres in the pleural space C. Poland, F. Murphy and K. Donaldson; 6. Experimental carcinogenicity of carbon nanotubes in the context of other fibres K. Unfried; 7. Fate and effects of carbon nanotubes following inhalation J. Ryman-Rasmussen, M. Andersen and J. Bonner; 8. Responses to pulmonary exposure to carbon nanotubes V. Castranova and R. Mercer; 9. Genotoxicity of carbon nanotubes R. Schins, C. Albrecht, K. Gerloff and D. van Berlo; 10. Carbon nanotube-cellular interactions; macrophages, epithelial and mesothelial cells V. Stone, M. Boyles, A. Kermanizadeh, J. Varet and H. Johnston; 11. Systemic health effects of carbon nanotubes following inhalation J. McDonald; 12. Dosimetry and metrology of carbon nanotubes L. Tran, L. MacCalman and R. Aitken; Index.

  11. Designing carbon markets. Part I: Carbon markets in time

    Energy Technology Data Exchange (ETDEWEB)

    Fankhauser, Samuel, E-mail: s.fankhauser@lse.ac.u [Grantham Research Institute and Centre for Climate Change Economics and Policy, London School of Economics, Houghton St, London WC2A 2AE (United Kingdom); Hepburn, Cameron, E-mail: cameron.hepburn@economics.ox.ac.u [Grantham Research Institute, London School of Economics, and Smith School for Enterprise and the Environment, Oxford University, 75 George Street, Oxford OX1 2BQ (United Kingdom)

    2010-08-15

    This paper analyses the design of carbon markets in time (i.e., intertemporally). It is part of a twin set of papers that ask, starting from first principles, what an optimal global carbon market would look like by around 2030. Our focus is on firm-level cap-and-trade systems, although much of what we say would also apply to government-level trading and carbon offset schemes. We examine the 'first principles' of temporal design that would help to maximise flexibility and to minimise costs, including banking and borrowing and other mechanisms to provide greater carbon price predictability and credibility over time.

  12. Designing carbon markets. Part 1. Carbon markets in time

    Energy Technology Data Exchange (ETDEWEB)

    Fankhauser, Samuel [Grantham Research Institute and Centre for Climate Change Economics and Policy, London School of Economics, Houghton St, London WC2A 2AE (United Kingdom); Hepburn, Cameron [Grantham Research Institute, London School of Economics, and Smith School for Enterprise and the Environment, Oxford University, 75 George Street, Oxford OX1 2BQ (United Kingdom)

    2010-08-15

    This paper analyses the design of carbon markets in time (i.e., intertemporally). It is part of a twin set of papers that ask, starting from first principles, what an optimal global carbon market would look like by around 2030. Our focus is on firm-level cap-and-trade systems, although much of what we say would also apply to government-level trading and carbon offset schemes. We examine the first principles of temporal design that would help to maximise flexibility and to minimise costs, including banking and borrowing and other mechanisms to provide greater carbon price predictability and credibility over time. (author)

  13. Multiporous carbon allotropes transformed from symmetry-matched carbon nanotubes

    Directory of Open Access Journals (Sweden)

    Yingxiang Cai

    2016-06-01

    Full Text Available Carbon nanotubes (CNTs with homogeneous diameters have been proven to transform into new carbon allotropes under pressure but no studies on the compression of inhomogeneous CNTs have been reported. In this study, we propose to build new carbon allotropes from the bottom-up by applying pressure on symmetry-matched inhomogeneous CNTs. We find that the (3,0 CNT with point group C3v and the (6,0 CNT with point group C6v form an all sp3 hybridized hexagonal 3060-Carbon crystal, but the (4,0 CNT with point group D4h and the (8,0 CNT with point group D8h polymerize into a sp2+sp3 hybridized tetragonal 4080-Carbon structure. Their thermodynamic, mechanical and dynamic stabilities show that they are potential carbon allotropes to be experimentally synthesized. The multiporous structures, excellently mechanical properties and special electronic structures (semiconductive 3060-Carbon and semimetallic 4080-Carbon imply their many potential applications, such as gases purification, hydrogen storage and lightweight semiconductor devices. In addition, we simulate their feature XRD patterns which are helpful for identifying the two carbon crystals in future experimental studies.

  14. Carbon Micronymphaea: Graphene on Vertically Aligned Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Jong Won Choi

    2013-01-01

    Full Text Available This paper describes the morphology of carbon nanomaterials such as carbon nanotube (CNT, graphene, and their hybrid structure under various operating conditions during a one-step synthesis via plasma-enhanced chemical vapor deposition (PECVD. We focus on the synthetic aspects of carbon hybrid material composed of heteroepitaxially grown graphene on top of a vertical array of carbon nanotubes, called carbon micronymphaea. We characterize the structural features of this unique nanocomposite by uses of electron microscopy and micro-Raman spectroscopy. We observe carbon nanofibers, poorly aligned and well-aligned vertical arrays of CNT sequentially as the growth temperature increases, while we always discover the carbon hybrids, called carbon micronymphaea, at specific cooling rate of 15°C/s, which is optimal for the carbon precipitation from the Ni nanoparticles in this study. We expect one-pot synthesized graphene-on-nanotube hybrid structure poses great potential for applications that demand ultrahigh surface-to-volume ratios with intact graphitic nature and directional electronic and thermal transports.

  15. Multiporous carbon allotropes transformed from symmetry-matched carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Yingxiang, E-mail: yingxiangcai@ncu.edu.cn; Wang, Hao; Xu, Shengliang; Hu, Yujie; Liu, Ning; Xu, Xuechun [Department of Physics, NanChang University, Jiangxi, Nanchang 330031 (China)

    2016-06-15

    Carbon nanotubes (CNTs) with homogeneous diameters have been proven to transform into new carbon allotropes under pressure but no studies on the compression of inhomogeneous CNTs have been reported. In this study, we propose to build new carbon allotropes from the bottom-up by applying pressure on symmetry-matched inhomogeneous CNTs. We find that the (3,0) CNT with point group C{sub 3v} and the (6,0) CNT with point group C{sub 6v} form an all sp{sup 3} hybridized hexagonal 3060-Carbon crystal, but the (4,0) CNT with point group D{sub 4h} and the (8,0) CNT with point group D{sub 8h} polymerize into a sp{sup 2}+sp{sup 3} hybridized tetragonal 4080-Carbon structure. Their thermodynamic, mechanical and dynamic stabilities show that they are potential carbon allotropes to be experimentally synthesized. The multiporous structures, excellently mechanical properties and special electronic structures (semiconductive 3060-Carbon and semimetallic 4080-Carbon) imply their many potential applications, such as gases purification, hydrogen storage and lightweight semiconductor devices. In addition, we simulate their feature XRD patterns which are helpful for identifying the two carbon crystals in future experimental studies.

  16. Carbon Nanotube-Enhanced Carbon-Phenenolic Ablator Material

    Science.gov (United States)

    Kikolaev, P.; Stackpoole, M.; Fan, W.; Cruden, B. A.; Waid, M.; Moloney, P.; Arepalli, S.; Arnold, J.; Partridge, H.; Yowell, L.

    2006-01-01

    This viewgraph presentation reviews the use of PICA (phenolic impregnated carbon ablator) as the selected material for heat shielding for future earth return vehicles. It briefly reviews the manufacturing of PICA and the advantages for the use of heat shielding, and then explains the reason for using Carbon Nanotubes to improve strength of phenolic resin that binds carbon fibers together. It reviews the work being done to create a carbon nanotube enhanced PICA. Also shown are various micrographic images of the various PICA materials.

  17. Evaluation of carbon-carbon for space engine nozzle

    Science.gov (United States)

    Suhoza, J. P.; Cawood, G. W.; Cawood, G. W.; Cawood, G. W.; Cawood, G. W.; Cawood, G. W.

    1986-01-01

    An investigation is underway to determine the suitability of carbon-carbon composite materials for lightweight nozzle extensions on the Orbit Transfer Vehicle (OTV). The best combinations of fiber precursor, matrix material, and oxidation protection coatings are being evaluated in a series of hot-fire tests in an O sub 2/H sub 2 rocket nozzle environment. Evaluation criteria include life expectancy (recession), strength to weight, producibility, maturity, and cost. A data base of carbon-carbon performance in the OTV nozzle environment will be established which may be used in designing a full-scale OTV nozzle extension.

  18. A better carbon footprint label

    DEFF Research Database (Denmark)

    Thøgersen, John; Nielsen, Kristian S.

    2016-01-01

    Based on insights from behavioral economics, it is suggested to extend carbon footprint labeling with information about relative performance, using the well-known “traffic light” color scheme to communicate relative performance. To test this proposition, the impact of a carbon footprint label......, participants saw the original Carbon Trust label and in the other condition they saw the same label, but with traffic light colors added to communicate the product’s relative performance in terms of carbon footprint. All included attributes were found to have a significant impact on consumer choices....... As expected, price and carbon footprint were negatively related to choice. Further, participants preferred organic to non-organic coffee and certification by a public authority. The effect of the carbon label is significantly stronger the more environmentally concerned the consumer is. Using colors...

  19. Fragmentation in Carbon Therapy Beams

    CERN Document Server

    Charara, Y M

    2010-01-01

    The state of the art Monte Carlo code HETC-HEDS was used to simulate spallation products, secondary neutron, and secondary proton production in A-150 Tissue Equivalent Plastic phantoms to investigate fragmentation of carbon therapy beams. For a 356 MeV/Nucleon carbon ion beam, production of charged particles heavier than protons was 0.24 spallation products per incident carbon ion with atomic numbers ranging from 1 through 5 (hydrogen to boron). In addition, there were 4.73 neutrons and 2.95 protons produced per incident carbon ion. Furthermore, as the incident energy increases, the neutron production rate increases at a rate of 20% per 10 MeV/nucleon. Secondary protons were created at a rate between 2.62-2.87 per carbon ion, while spallation products were created at a rate between 0.20-0.24 per carbon ion.

  20. Carbon Nanomaterials as Antibacterial Colloids

    Directory of Open Access Journals (Sweden)

    Michael Maas

    2016-07-01

    Full Text Available Carbon nanomaterials like graphene, carbon nanotubes, fullerenes and the various forms of diamond have attracted great attention for their vast potential regarding applications in electrical engineering and as biomaterials. The study of the antibacterial properties of carbon nanomaterials provides fundamental information on the possible toxicity and environmental impact of these materials. Furthermore, as a result of the increasing prevalence of resistant bacteria strains, the development of novel antibacterial materials is of great importance. This article reviews current research efforts on characterizing the antibacterial activity of carbon nanomaterials from the perspective of colloid and interface science. Building on these fundamental findings, recent functionalization strategies for enhancing the antibacterial effect of carbon nanomaterials are described. The review concludes with a comprehensive outlook that summarizes the most important discoveries and trends regarding antibacterial carbon nanomaterials.

  1. Stable prenucleation calcium carbonate clusters.

    Science.gov (United States)

    Gebauer, Denis; Völkel, Antje; Cölfen, Helmut

    2008-12-19

    Calcium carbonate forms scales, geological deposits, biominerals, and ocean sediments. Huge amounts of carbon dioxide are retained as carbonate ions, and calcium ions represent a major contribution to water hardness. Despite its relevance, little is known about the precipitation mechanism of calcium carbonate, and specified complex crystal structures challenge the classical view on nucleation considering the formation of metastable ion clusters. We demonstrate that dissolved calcium carbonate in fact contains stable prenucleation ion clusters forming even in undersaturated solution. The cluster formation can be characterized by means of equilibrium thermodynamics, applying a multiple-binding model, which allows for structural preformation. Stable clusters are the relevant species in calcium carbonate nucleation. Such mechanisms may also be important for the crystallization of other minerals.

  2. Carbon Ion Therapy

    DEFF Research Database (Denmark)

    Bassler, Niels; Hansen, David Christoffer; Herrmann, Rochus

    On the importance of choice of target size for selective boosting of hypoxic tumor subvolumina in carbon ion therapy Purpose: Functional imaging methods in radiotherapy are maturing and can to some extent uncover radio resistant structures found within a tumour entity. Selective boost of identified...... hypoxic subvolumina with high-LET radiation may in principle lead to increased tumour control due to LET-dependence of the oxygen enhancement ratio (OER). Here, we demonstrate the importance of minimizing field sizes in order not to dilute the dose average LET by quantifying the OER as a function of PTV...

  3. Global Carbon Budget 2015

    Science.gov (United States)

    Le Quéré, C.; Moriarty, R.; Andrew, R. M.; Canadell, J. G.; Sitch, S.; Korsbakken, J. I.; Friedlingstein, P.; Peters, G. P.; Andres, R. J.; Boden, T. A.; Houghton, R. A.; House, J. I.; Keeling, R. F.; Tans, P.; Arneth, A.; Bakker, D. C. E.; Barbero, L.; Bopp, L.; Chang, J.; Chevallier, F.; Chini, L. P.; Ciais, P.; Fader, M.; Feely, R. A.; Gkritzalis, T.; Harris, I.; Hauck, J.; Ilyina, T.; Jain, A. K.; Kato, E.; Kitidis, V.; Klein Goldewijk, K.; Koven, C.; Landschützer, P.; Lauvset, S. K.; Lefèvre, N.; Lenton, A.; Lima, I. D.; Metzl, N.; Millero, F.; Munro, D. R.; Murata, A.; Nabel, J. E. M. S.; Nakaoka, S.; Nojiri, Y.; O'Brien, K.; Olsen, A.; Ono, T.; Pérez, F. F.; Pfeil, B.; Pierrot, D.; Poulter, B.; Rehder, G.; Rödenbeck, C.; Saito, S.; Schuster, U.; Schwinger, J.; Séférian, R.; Steinhoff, T.; Stocker, B. D.; Sutton, A. J.; Takahashi, T.; Tilbrook, B.; van der Laan-Luijkx, I. T.; van der Werf, G. R.; van Heuven, S.; Vandemark, D.; Viovy, N.; Wiltshire, A.; Zaehle, S.; Zeng, N.

    2015-12-01

    Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe data sets and a methodology to quantify all major components of the global carbon budget, including their uncertainties, based on the combination of a range of data, algorithms, statistics, and model estimates and their interpretation by a broad scientific community. We discuss changes compared to previous estimates as well as consistency within and among components, alongside methodology and data limitations. CO2 emissions from fossil fuels and industry (EFF) are based on energy statistics and cement production data, while emissions from land-use change (ELUC), mainly deforestation, are based on combined evidence from land-cover-change data, fire activity associated with deforestation, and models. The global atmospheric CO2 concentration is measured directly and its rate of growth (GATM) is computed from the annual changes in concentration. The mean ocean CO2 sink (SOCEAN) is based on observations from the 1990s, while the annual anomalies and trends are estimated with ocean models. The variability in SOCEAN is evaluated with data products based on surveys of ocean CO2 measurements. The global residual terrestrial CO2 sink (SLAND) is estimated by the difference of the other terms of the global carbon budget and compared to results of independent dynamic global vegetation models forced by observed climate, CO2, and land-cover change (some including nitrogen-carbon interactions). We compare the mean land and ocean fluxes and their variability to estimates from three atmospheric inverse methods for three broad latitude bands. All uncertainties are reported as ±1σ, reflecting the current capacity to characterise the annual estimates of each component of the global

  4. Global Carbon Budget 2016

    Science.gov (United States)

    Le Quéré, Corinne; Andrew, Robbie M.; Canadell, Josep G.; Sitch, Stephen; Korsbakken, Jan Ivar; Peters, Glen P.; Manning, Andrew C.; Boden, Thomas A.; Tans, Pieter P.; Houghton, Richard A.; Keeling, Ralph F.; Alin, Simone; Andrews, Oliver D.; Anthoni, Peter; Barbero, Leticia; Bopp, Laurent; Chevallier, Frédéric; Chini, Louise P.; Ciais, Philippe; Currie, Kim; Delire, Christine; Doney, Scott C.; Friedlingstein, Pierre; Gkritzalis, Thanos; Harris, Ian; Hauck, Judith; Haverd, Vanessa; Hoppema, Mario; Klein Goldewijk, Kees; Jain, Atul K.; Kato, Etsushi; Körtzinger, Arne; Landschützer, Peter; Lefèvre, Nathalie; Lenton, Andrew; Lienert, Sebastian; Lombardozzi, Danica; Melton, Joe R.; Metzl, Nicolas; Millero, Frank; Monteiro, Pedro M. S.; Munro, David R.; Nabel, Julia E. M. S.; Nakaoka, Shin-ichiro; O'Brien, Kevin; Olsen, Are; Omar, Abdirahman M.; Ono, Tsuneo; Pierrot, Denis; Poulter, Benjamin; Rödenbeck, Christian; Salisbury, Joe; Schuster, Ute; Schwinger, Jörg; Séférian, Roland; Skjelvan, Ingunn; Stocker, Benjamin D.; Sutton, Adrienne J.; Takahashi, Taro; Tian, Hanqin; Tilbrook, Bronte; van der Laan-Luijkx, Ingrid T.; van der Werf, Guido R.; Viovy, Nicolas; Walker, Anthony P.; Wiltshire, Andrew J.; Zaehle, Sönke

    2016-11-01

    Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere - the "global carbon budget" - is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe data sets and methodology to quantify all major components of the global carbon budget, including their uncertainties, based on the combination of a range of data, algorithms, statistics, and model estimates and their interpretation by a broad scientific community. We discuss changes compared to previous estimates and consistency within and among components, alongside methodology and data limitations. CO2 emissions from fossil fuels and industry (EFF) are based on energy statistics and cement production data, respectively, while emissions from land-use change (ELUC), mainly deforestation, are based on combined evidence from land-cover change data, fire activity associated with deforestation, and models. The global atmospheric CO2 concentration is measured directly and its rate of growth (GATM) is computed from the annual changes in concentration. The mean ocean CO2 sink (SOCEAN) is based on observations from the 1990s, while the annual anomalies and trends are estimated with ocean models. The variability in SOCEAN is evaluated with data products based on surveys of ocean CO2 measurements. The global residual terrestrial CO2 sink (SLAND) is estimated by the difference of the other terms of the global carbon budget and compared to results of independent dynamic global vegetation models. We compare the mean land and ocean fluxes and their variability to estimates from three atmospheric inverse methods for three broad latitude bands. All uncertainties are reported as ±1σ, reflecting the current capacity to characterise the annual estimates of each component of the global carbon budget. For the last decade available (2006-2015), EFF was 9

  5. Carbon Dioxide Fixation by Microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, Victoria H.; Calvin, Melvin

    1951-07-24

    Resting cells of eleven microorganisms were exposed to radioactive carbon dioxide for 40 minutes. The radioactive compounds formed during this time were separated and identified by paper chromatography. Resting cells of Lactobacillus casei fixed no carbon dioxide and growing cells fixed carbon dioxide primarily in malic and aspartic acids. All of the radioactive compounds formed could have become radioactive by reversal of known decarboxylation reactions.

  6. Carbon. Examples of Property Realization

    Directory of Open Access Journals (Sweden)

    I.A. Kossko

    2013-11-01

    Full Text Available Examples of realization of carbon properties in formation of section near-surface boundaries defining the mechanism of oxidizing (normal wear are presented. Synthesis of strengt hening diamond- lonsdaleite -carbene «frame» and graphite with function of solid lubricant on a friction surface in high-desperse carbon environment is reviewed. Prospects of carbon ap placation in implementation of the concept of electronics on one element, and also use of thin-film structures of amorphous carbon – metal for data recording are discussed.

  7. Carbon nanotube IR detectors (SV)

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, F. L.

    2012-03-01

    Sandia National Laboratories (Sandia) and Lockheed Martin Corporation (LMC) collaborated to (1) evaluate the potential of carbon nanotubes as channels in infrared (IR) photodetectors; (2) assemble and characterize carbon nanotube electronic devices and measure the photocurrent generated when exposed to infrared light;(3) compare the performance of the carbon nanotube devices with that of traditional devices; and (4) develop and numerically implement models of electronic transport and opto-electronic behavior of carbon nanotube infrared detectors. This work established a new paradigm for photodetectors.

  8. Carbon dioxide and climate

    Energy Technology Data Exchange (ETDEWEB)

    1990-10-01

    Scientific and public interest in greenhouse gases, climate warming, and global change virtually exploded in 1988. The Department's focused research on atmospheric CO{sub 2} contributed sound and timely scientific information to the many questions produced by the groundswell of interest and concern. Research projects summarized in this document provided the data base that made timely responses possible, and the contributions from participating scientists are genuinely appreciated. In the past year, the core CO{sub 2} research has continued to improve the scientific knowledge needed to project future atmospheric CO{sub 2} concentrations, to estimate climate sensitivity, and to assess the responses of vegetation to rising concentrations of CO{sub 2} and to climate change. The Carbon Dioxide Research Program's goal is to develop sound scientific information for policy formulation and governmental action in response to changes of atmospheric CO{sub 2}. The Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1990 and gives a brief overview of objectives, organization, and accomplishments.

  9. Carbon nanotube computer.

    Science.gov (United States)

    Shulaker, Max M; Hills, Gage; Patil, Nishant; Wei, Hai; Chen, Hong-Yu; Wong, H-S Philip; Mitra, Subhasish

    2013-09-26

    The miniaturization of electronic devices has been the principal driving force behind the semiconductor industry, and has brought about major improvements in computational power and energy efficiency. Although advances with silicon-based electronics continue to be made, alternative technologies are being explored. Digital circuits based on transistors fabricated from carbon nanotubes (CNTs) have the potential to outperform silicon by improving the energy-delay product, a metric of energy efficiency, by more than an order of magnitude. Hence, CNTs are an exciting complement to existing semiconductor technologies. Owing to substantial fundamental imperfections inherent in CNTs, however, only very basic circuit blocks have been demonstrated. Here we show how these imperfections can be overcome, and demonstrate the first computer built entirely using CNT-based transistors. The CNT computer runs an operating system that is capable of multitasking: as a demonstration, we perform counting and integer-sorting simultaneously. In addition, we implement 20 different instructions from the commercial MIPS instruction set to demonstrate the generality of our CNT computer. This experimental demonstration is the most complex carbon-based electronic system yet realized. It is a considerable advance because CNTs are prominent among a variety of emerging technologies that are being considered for the next generation of highly energy-efficient electronic systems.

  10. Advanced carbon nanotubes functionalization

    Science.gov (United States)

    Setaro, A.

    2017-10-01

    Similar to graphene, carbon nanotubes are materials made of pure carbon in its sp2 form. Their extended conjugated π-network provides them with remarkable quantum optoelectronic properties. Frustratingly, it also brings drawbacks. The π-π stacking interaction makes as-produced tubes bundle together, blurring all their quantum properties. Functionalization aims at modifying and protecting the tubes while hindering π-π stacking. Several functionalization strategies have been developed to circumvent this limitation in order for nanotubes applications to thrive. In this review, we summarize the different approaches established so far, emphasizing the balance between functionalization efficacy and the preservation of the tubes’ properties. Much attention will be given to a functionalization strategy overcoming the covalent-noncovalent dichotomy and to the implementation of two advanced functionalization schemes: (a) conjugation with molecular switches, to yield hybrid nanosystems with chemo-physical properties that can be tuned in a controlled and reversible way, and; (b) plasmonic nanosystems, whose ability to concentrate and enhance the electromagnetic fields can be taken advantage of to enhance the optical response of the tubes.

  11. Global Carbon Budget 2016

    Science.gov (United States)

    Quéré, Corinne Le; Andrew, Robbie M.; Canadell, Josep G.; Sitch, Stephen; Korsbakken, Jan Ivar; Peters, Glen P.; Manning, Andrew C.; Boden, Thomas A.; Tans, Pieter P.; Houghton, Richard A.; hide 12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20170008485_hide">

    2016-01-01

    Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere the global carbon budget is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe data sets and methodology to quantify all major components of the global carbon budget, including their uncertainties, based on the combination of a range of data, algorithms, statistics, and model estimates and their interpretation by a broad scientific community. We discuss changes compared to previous estimates and consistency within and among components, alongside methodology and data limitations. CO2 emissions from fossil fuels and industry (EFF) are based on energy statistics and cement production data, respectively, while emissions from land-use change (ELUC), mainly deforestation, are based on combined evidence from land-cover change data, fire activity associated with deforestation, and models. The global atmospheric CO2 concentration is measured directly and its rate of growth (GATM) is computed from the annual changes in concentration. The mean ocean CO2 sink (SOCEAN) is based on observations from the 1990s, while the annual anomalies and trends are estimated with ocean models. The variability in SOCEAN is evaluated with data products based on surveys of ocean CO2 measurements. The global residual terrestrial CO2 sink (SLAND) is estimated by the difference of the other terms of the global carbon budget and compared to results of independent dynamic global vegetation models. We compare the mean land and ocean fluxes and their variability to estimates from three atmospheric inverse methods for three broad latitude bands. All uncertainties are reported as +/- 1(sigma), reflecting the current capacity to characterize the annual estimates of each component of the global carbon budget. For the last decade available (2006-2015), EFF was 9

  12. Condensation of carbon in radioactive supernova gas.

    Science.gov (United States)

    Clayton, D D; Liu, W; Dalgarno, A

    1999-02-26

    Chemistry resulting in the formation of large carbon-bearing molecules and dust in the interior of an expanding supernova was explored, and the equations governing their abundances were solved numerically. Carbon dust condenses from initially gaseous carbon and oxygen atoms because energetic electrons produced by radioactivity in the supernova cause dissociation of the carbon monoxide molecules, which would otherwise form and limit the supply of carbon atoms. The resulting free carbon atoms enable carbon dust to grow faster by carbon association than the rate at which the dust can be destroyed by oxidation. The origin of presolar micrometer-sized carbon solids that are found in meteorites is thereby altered.

  13. Carbon and oxygen isotope compositions of the carbonate facies in ...

    Indian Academy of Sciences (India)

    The Vindhyan sedimentary succession in central India spans a wide time bracket from the Paleopro- terozoic to the Neoproterozoic period.Chronostratigraphic significance of stable carbon and oxygen isotope ratios of the carbonate phase in Vindhyan sediments has been discussed in some recent studies.However,the ...

  14. Studies of activated carbon and carbon black for supercapacitor applications

    Energy Technology Data Exchange (ETDEWEB)

    Richner, R.; Mueller, S.; Koetz, R.; Wokaun, A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    Carbon Black and activated carbon materials providing high surface areas and a distinct pore distribution are prime materials for supercapacitor applications at frequencies < 0.5 Hz. A number of these materials were tested for their specific capacitance, surface and pore size distribution. High capacitance electrodes were manufactured on the laboratory scale with attention to ease of processability. (author) 1 fig., 1 ref.

  15. Electron irradiation of carbon dioxide-carbon disulphide ice analog ...

    Indian Academy of Sciences (India)

    Abstract. Carbon dioxide (CO2) and carbon disulphide (CS2) molecular ice mixture was prepared under low temperature (85 K) astrochemical conditions. The icy mixture irradiated with keV electrons simulates the irradiation environment experienced by icy satellites and Interstellar Icy Mantles (IIM). Upon electron irradi-.

  16. High-Melt Carbon-Carbon Coating for Nozzle Extensions

    Science.gov (United States)

    Thompson, James

    2015-01-01

    Carbon-Carbon Advanced Technologies, Inc. (C-CAT), has developed a high-melt coating for use in nozzle extensions in next-generation spacecraft. The coating is composed primarily of carbon-carbon, a carbon-fiber and carbon-matrix composite material that has gained a spaceworthy reputation due to its ability to withstand ultrahigh temperatures. C-CAT's high-melt coating embeds hafnium carbide (HfC) and zirconium diboride (ZrB2) within the outer layers of a carbon-carbon structure. The coating demonstrated enhanced high-temperature durability and suffered no erosion during a test in NASA's Arc Jet Complex. (Test parameters: stagnation heat flux=198 BTD/sq ft-sec; pressure=.265 atm; temperature=3,100 F; four cycles totaling 28 minutes) In Phase I of the project, C-CAT successfully demonstrated large-scale manufacturability with a 40-inch cylinder representing the end of a nozzle extension and a 16-inch flanged cylinder representing the attach flange of a nozzle extension. These demonstrators were manufactured without spalling or delaminations. In Phase II, C-CAT worked with engine designers to develop a nozzle extension stub skirt interfaced with an Aerojet Rocketdyne RL10 engine. All objectives for Phase II were successfully met. Additional nonengine applications for the coating include thermal protection systems (TPS) for next-generation spacecraft and hypersonic aircraft.

  17. Thermal carbonization of nanoporous silicon: Formation of carbon ...

    Indian Academy of Sciences (India)

    An interesting phenomenon is observed while carrying out thermal carbonization of porous silicon (PS) with an aim to arrest the natural surface degradation, and it is a burning issue for PS-based device applications. A tubular carbon structure has been observed on the PS surface. Raman, Fourier transform infrared ...

  18. Carbon-Carbon High Melt Coating for Nozzle Extensions Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Melt Coating system is applied to a carbon-carbon structure and embeds HfC, ZrB2 in the outer layers. ACC High Melt builds on the time tested base material...

  19. Carbon storage and carbon emission offset potential in an African ...

    African Journals Online (AJOL)

    Tropical deforestation contributes to atmospheric concentrations of greenhouse gases, linked to global climate change. In response, emerging markets for carbon emission offsets offer developing nations added incentives for rehabilitation and reforestation that increase terrestrial carbon storage. The Lower Tana River ...

  20. Reducibility of platinum supported on nanostructured carbons

    NARCIS (Netherlands)

    Plomp, A.J.|info:eu-repo/dai/nl/304837598; Schubert, T.; Storr, U.; de Jong, K.P.|info:eu-repo/dai/nl/06885580X; Bitter, J.H.|info:eu-repo/dai/nl/160581435

    2009-01-01

    The nanostructure of graphite like carbon, i.e. carbon nanofibers (CNF), carbon nanotubes (CNT) and carbon nanoplatelets (CNP), displayed a significant influence on the reducibility of platinum deposited on these carbons. The onset temperature for reduction increased from 461 K for Pt/CNF to 466 K

  1. 21 CFR 184.1191 - Calcium carbonate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium carbonate. 184.1191 Section 184.1191 Food... Specific Substances Affirmed as GRAS § 184.1191 Calcium carbonate. (a) Calcium carbonate (CaCO3, CAS Reg... soda process”; (2) By precipitation of calcium carbonate from calcium hydroxide in the “Carbonation...

  2. Carbon-Carbon High Melt Coating for Nozzle and Nozzle Extensions Project

    Data.gov (United States)

    National Aeronautics and Space Administration — C-CAT, which has proven carbon-carbon fabrication capabilities, will investigate use of ACC-6 High Melt oxidation protective system on carbon-carbon for use on the...

  3. Cryogenic Adsorption of Nitrogen and Carbon Dioxide in Activated Carbon

    Science.gov (United States)

    Shen, Fuzhi; Liu, Huiming; Xu, Dong; Zhang, Hengcheng; Lu, Junfeng; Li, Laifeng

    2017-09-01

    Activated carbon have been used for a long time at low temperature for cryogenic applications. The knowledge of adsorption characteristics of activated carbon at cryogenic temperature is essential for some specific applications. However, such experimental data are very scare in the literature. In order to measure the adsorption characteristics of activated carbon under variable cryogenic temperatures, an adsorption measurement device was presented. The experiment system is based on the commercially available PCT-pro adsorption analyzer coupled to a two-stage Gifford McMahon refrigerator, which allows the sample to be cooled to 4.2K. Cryogenic environment can be maintained steadily without the cryogenic liquid through the cryocooler and temperature can be controlled precisely between 5K and 300K by the temperature controller. Adsorption measurements were performed in activated carbon for carbon dioxide and nitrogen and the adsorption isotherm were obtained.

  4. The Vibration of a Linear Carbon Chain in Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Dongqing Ding

    2017-04-01

    Full Text Available An explicit solution for the vibration of a carbon chain inside carbon nanotubes (CNTs was obtained using continuum modeling of the van der Waals (vdW interactions between them. The effect of the initial tensile force and the amplitude of the carbon chain as well as the radii of the CNTs on the vibration frequency were analyzed in detail, respectively. Our analytical results show that the vibration frequency of the carbon chain in a (5,5 CNT could be around two orders of magnitude higher than that of an independent carbon chain without initial tensile force. For a given CNT radius, the vibration frequency nonlinearly increases with increasing amplitude and initial tensile force. The obtained analytical cohesive energy and vibration frequency are reasonable by comparison of present molecular dynamics (MD simulations. These findings will be a great help towards understanding the vibration property of a nanowire in nanotubes, and designing nanoelectromechanical devices.

  5. Finding Paleoclimates Using Pedogenic Carbonates

    Science.gov (United States)

    Garapaty, C.; Bella Pratt, K.; Blisniuk, K.

    2016-12-01

    Carbonate rinds naturally form on the undersides of clasts in desert soil. These carbonate rinds can be used to determine past climates in these environments because they contain certain radioactive isotopes and stable isotopes. Radioactive isotopes can provide the age of soil formation because carbonate rinds only form after the soil. When the carbonates are forming on the rock, in desert soil, they trap miniscule amounts of uranium which will radioactively decay into thorium. Therefore, the uranium to thorium ratio found when the carbonates are analyzed can accurately give you the date of the sample. On the other hand stable isotopes help determine the average temperature at the time the carbonate was formed. The oxygen in the CO3- (carbonate) are usually 16O and 18O. The ratio of 16O to 18O can give you the temperature of the environment when the carbonates formed. This ratio depends on temperature because water with 16O evaporates first since it is lighter and 18O precipitates more easily because it is heavier. Evaporation, precipitation, and temperature change, easily alters the concentration of the ratio of 16O to 18O so it is easy to calculate the temperature, in that area and at that time, from it. The samples I worked on are from the Sonoran Desert in Southern California. I used a microscope, tweezers and a small pick to remove the carbonate from the clast and remove the biotite and other contamination from the carbonate. Later, we wash the samples by hand and by using an ultrasonic machine to make them even cleaner by washing away any loose material. We had to remove the biotite and wash away the loose material because the carbonates need to be clean in order for us to analyze it accurately.

  6. Carbon Fiber Biocompatibility for Implants.

    Science.gov (United States)

    Petersen, Richard

    Carbon fibers have multiple potential advantages in developing high-strength biomaterials with a density close to bone for better stress transfer and electrical properties that enhance tissue formation. As a breakthrough example in biomaterials, a 1.5 mm diameter bisphenol-epoxy/carbon-fiber-reinforced composite rod was compared for two weeks in a rat tibia model with a similar 1.5 mm diameter titanium-6-4 alloy screw manufactured to retain bone implants. Results showed that carbon-fiber-reinforced composite stimulated osseointegration inside the tibia bone marrow measured as percent bone area (PBA) to a great extent when compared to the titanium-6-4 alloy at statistically significant levels. PBA increased significantly with the carbon-fiber composite over the titanium-6-4 alloy for distances from the implant surfaces of 0.1 mm at 77.7% vs. 19.3% (p carbon fiber properties that increased PBA for enhanced implant osseointegration. Carbon fibers acting as polymer coated electrically conducting micro-biocircuits appear to provide a biocompatible semi-antioxidant property to remove damaging electron free radicals from the surrounding implant surface. Further, carbon fibers by removing excess electrons produced from the cellular mitochondrial electron transport chain during periods of hypoxia perhaps stimulate bone cell recruitment by free-radical chemotactic influences. In addition, well-studied bioorganic cell actin carbon fiber growth would appear to interface in close contact with the carbon-fiber-reinforced composite implant. Resulting subsequent actin carbon fiber/implant carbon fiber contacts then could help in discharging the electron biological overloads through electrochemical gradients to lower negative charges and lower concentration.

  7. Activated Carbon, Carbon Nanofiber and Carbon Nanotube Supported Molybdenum Carbide Catalysts for the Hydrodeoxygenation of Guaiacol

    Directory of Open Access Journals (Sweden)

    Eduardo Santillan-Jimenez

    2015-03-01

    Full Text Available Molybdenum carbide was supported on three types of carbon support—activated carbon; multi-walled carbon nanotubes; and carbon nanofibers—using ammonium molybdate and molybdic acid as Mo precursors. The use of activated carbon as support afforded an X-ray amorphous Mo phase, whereas crystalline molybdenum carbide phases were obtained on carbon nanofibers and, in some cases, on carbon nanotubes. When the resulting catalysts were tested in the hydrodeoxygenation (HDO of guaiacol in dodecane, catechol and phenol were obtained as the main products, although in some instances significant amounts of cyclohexane were produced. The observation of catechol in all reaction mixtures suggests that guaiacol was converted into phenol via sequential demethylation and HDO, although the simultaneous occurrence of a direct demethoxylation pathway cannot be discounted. Catalysts based on carbon nanofibers generally afforded the highest yields of phenol; notably, the only crystalline phase detected in these samples was Mo2C or Mo2C-ζ, suggesting that crystalline Mo2C is particularly selective to phenol. At 350 °C, carbon nanofiber supported Mo2C afforded near quantitative guaiacol conversion, the selectivity to phenol approaching 50%. When guaiacol HDO was performed in the presence of acetic acid and furfural, guaiacol conversion decreased, although the selectivity to both catechol and phenol was increased.

  8. Carbon recycling in ophiolite-hosted carbonates, Oman-UAE

    Science.gov (United States)

    Stephen, A.; Jenkin, G. R.; Smith, D. J.; Styles, M. T.; Naden, J.; Boyce, A. J.; Bryant, C. L.

    2013-12-01

    Large-scale surface and subsurface freshwater carbonate deposits of probable Quaternary age have formed on the Oman-UAE ophiolite. Here, serpentinisation reactions in ultramafic rocks have produced calcite and magnesite. These carbonates are frequently cited as examples of natural atmospheric CO2 sequestration, but the possibility of carbon recycling has not been addressed. The aim of this study is to assess the degree of atmospheric CO2 being incorporated into carbonates versus that which has been recycled from alternative sources such as soil CO2, or limestones that underlie the ophiolite. This has been determined through δ13C/δ18O, 87Sr/86Sr and 14C analysis of all major carbonate lithofacies identified. Our analyses of modern carbonate crusts forming on the surface of stagnant hyperalkaline (pH >11) waters show highly depleted δ13C and δ18O values (-25.5‰ ×0.5 PDB and -16.8‰ ×0.5 PDB respectively). This depletion has been attributed to a kinetic isotope effect occurring during atmospheric CO2 exchange with Ca(OH)2 hyperalkaline waters [1]. By comparison, inactive travertine deposits show a large range in δ13C (-10.5 to -21.8‰ PDB) which lies on a trajectory from the composition of modern crusts towards bicarbonate fluids in equilibrium with soil CO2. We interpret this trend as being produced by the mixing of different carbon sources, either at the time of formation or during later alteration. Modern carbonates and inactive travertines also have 87Sr/86Sr ratios and Sr concentrations similar to Cretaceous and Tertiary limestones which surround the ophiolite, whilst subsurface veins also display 87Sr/86Sr ratios similar to these Cretaceous limestones. Carbon recycling can also be determined with 14C. Modern atmospheric CO2 has a global average of 105-106% modern 14C (pMC), therefore freshwater carbonates forming solely from atmospheric CO2 would be expected to contain >100 pMC. However, modern carbonates display varied results from 94.5-101.4 p

  9. Methods of analyzing carbon nanostructures, methods of preparation of analytes from carbon nanostructures, and systems for analyzing carbon nanostructures

    KAUST Repository

    Da Costa, Pedro Miquel Ferreira Joaquim

    2016-09-09

    Provided herein is a method determining the concentration of impurities in a carbon material, comprising: mixing a flux and a carbon material to form a mixture, wherein the carbon material is selected from the group consisting of graphene, carbon nanotubes, fullerene, carbon onions, graphite, carbon fibers, and a combination thereof; heating the mixture using microwave energy to form fused materials; dissolution of the fused materials in an acid mixture; and measuring the concentration of one or more impurities.

  10. The Carbon City Index (CCI)

    DEFF Research Database (Denmark)

    Boyd, Britta; Straatman, Bas; Mangalagiu, Diana

    This paper presents a consumption-based Carbon City Index for CO2 emissions in a city. The index is derived from regional consumption and not from regional production. It includes imports and exports of emissions, factual emission developments, green investments as well as low carbon city...

  11. corrosion inhibitor for carbon steels

    African Journals Online (AJOL)

    potentiodynamic polarisation techniques. It was found that. CNSL reduces the extent of the electrochemical processes taking place on carbon steel undergoing corrosion. The corrosion rate of the carbon steel was reduced by over 92 % when only 300 ppm of CNSL was applied. This indicates that. CNSL is a potential ...

  12. Psychological effectiveness of carbon labelling

    Science.gov (United States)

    Beattie, Geoffrey

    2012-04-01

    Despite the decision by supermarket-giant Tesco to delay its plan to add carbon-footprint information onto all of its 70,000 products, carbon labelling, if carefully designed, could yet change consumer behaviour. However, it requires a new type of thinking about consumers and much additional work.

  13. Breaking Carbon Lock-in

    DEFF Research Database (Denmark)

    Driscoll, Patrick Arthur

    2014-01-01

    This central focus of this paper is to highlight the ways in which path dependencies and increasing returns (network effects) serve to reinforce carbon lock-in in large-scale road transportation infrastructure projects. Breaking carbon lock-in requires drastic changes in the way we plan future...

  14. Carbon accumulation in European forests

    NARCIS (Netherlands)

    Ciais, P.; Schelhaas, M.J.; Zaehle, S.; Piao, S.L.; Cescatti, A.; Liski, J.; Luyssaert, S.; Le-Maire, G.; Schulze, E.D.; Bouriaud, O.; Freibauer, A.; Valentini, R.; Nabuurs, G.J.

    2008-01-01

    European forests are intensively exploited for wood products, yet they also form a sink for carbon. European forest inventories, available for the past 50 years, can be combined with timber harvest statistics to assess changes in this carbon sink. Analysis of these data sets between 1950 and 2000

  15. Impregnating Coal With Calcium Carbonate

    Science.gov (United States)

    Sharma, Pramod K.; Voecks, Gerald E.; Gavalas, George R.

    1991-01-01

    Relatively inexpensive process proposed for impregnating coal with calcium carbonate to increase rates of gasification and combustion of coal and to reduce emission of sulfur by trapping sulfur in calcium sulfide. Process involves aqueous-phase reactions between carbon dioxide (contained within pore network of coal) and calcium acetate. Coal impregnated with CO2 by exposing it to CO2 at high pressure.

  16. Radiation Effects in Carbon Nanoelectronics

    Directory of Open Access Journals (Sweden)

    Cory D. Cress

    2012-07-01

    Full Text Available We experimentally investigate the effects of Co-60 irradiation on the electrical properties of single-walled carbon nanotube and graphene field-effect transistors. We observe significant differences in the radiation response of devices depending on their irradiation environment, and confirm that, under controlled conditions, standard dielectric hardening approaches are applicable to carbon nanoelectronics devices.

  17. Carbon Storage in US Wetlands.

    Science.gov (United States)

    Background/Question/Methods Wetland soils contain some of the highest stores of soil carbon in the biosphere. However, there is little understanding of the quantity and distribution of carbon stored in US wetlands or of the potential effects of human disturbance on these stocks. ...

  18. Quantum transport in carbon nanotubes

    NARCIS (Netherlands)

    Jarillo-Herrero, P.D.

    2005-01-01

    Electronic transport through nanostructures can be very different from trans- port in macroscopic conductors, especially at low temperatures. Carbon na- notubes are tiny cylinders made of carbon atoms. Their remarkable electronic and mechanical properties, together with their small size (a few nm in

  19. Hydrogen storage in carbon nanotubes.

    Science.gov (United States)

    Hirscher, M; Becher, M

    2003-01-01

    The article gives a comprehensive overview of hydrogen storage in carbon nanostructures, including experimental results and theoretical calculations. Soon after the discovery of carbon nanotubes in 1991, different research groups succeeded in filling carbon nanotubes with some elements, and, therefore, the question arose of filling carbon nanotubes with hydrogen by possibly using new effects such as nano-capillarity. Subsequently, very promising experiments claiming high hydrogen storage capacities in different carbon nanostructures initiated enormous research activity. Hydrogen storage capacities have been reported that exceed the benchmark for automotive application of 6.5 wt% set by the U.S. Department of Energy. However, the experimental data obtained with different methods for various carbon nanostructures show an extreme scatter. Classical calculations based on physisorption of hydrogen molecules could not explain the high storage capacities measured at ambient temperature, and, assuming chemisorption of hydrogen atoms, hydrogen release requires temperatures too high for technical applications. Up to now, only a few calculations and experiments indicate the possibility of an intermediate binding energy. Recently, serious doubt has arisen in relation to several key experiments, causing considerable controversy. Furthermore, high hydrogen storage capacities measured for carbon nanofibers did not survive cross-checking in different laboratories. Therefore, in light of today's knowledge, it is becoming less likely that at moderate pressures around room temperature carbon nanostructures can store the amount of hydrogen required for automotive applications.

  20. Assimilation of Unusual Carbon Compounds

    NARCIS (Netherlands)

    Middelhoven, W.J.

    2009-01-01

    Yeast taxa traditionally are distinguished by growth tests on several sugars and organic acids. During the last decades it became apparent that many yeast species assimilate a much greater variety of naturally occurring carbon compounds as sole source of carbon and energy. These abilities are

  1. 40 CFR 86.316-79 - Carbon monoxide and carbon dioxide analyzer specifications.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Carbon monoxide and carbon dioxide... Test Procedures § 86.316-79 Carbon monoxide and carbon dioxide analyzer specifications. (a) Carbon monoxide and carbon dioxide measurements are to be made with nondispersive infrared (NDIR) an analyzers. (b...

  2. Allyl 4-hydroxyphenyl carbonate

    Directory of Open Access Journals (Sweden)

    Víctor Hugo Flores Ahuactzin

    2009-07-01

    Full Text Available The title molecule, C10H10O4, is a functionalized carbonate used in the synthetic route to organic glasses. The central CH fragment of the allyl group is disordered over two positions, with occupancies in a 0.758 (10:0.242 (10ratio. This disorder reflects the torsional flexibility of the oxygen–allyl group, although both disordered parts present the expected anticlinal conformation, with O—CH2—CH=CH2 torsion angles of −111 (2 and 119.1 (4°. The crystal structure is based on chains parallel to [010], formed by O...H—O hydrogen bonds involving hydroxyl and carbonyl groups as donors and acceptors, respectively. The molecular packing is further stabilized by two weak C—H...π contacts from the benzene ring of the asymmetric unit with two benzene rings of neighboring molecules.

  3. Forecasting carbon dioxide emissions.

    Science.gov (United States)

    Zhao, Xiaobing; Du, Ding

    2015-09-01

    This study extends the literature on forecasting carbon dioxide (CO2) emissions by applying the reduced-form econometrics approach of Schmalensee et al. (1998) to a more recent sample period, the post-1997 period. Using the post-1997 period is motivated by the observation that the strengthening pace of global climate policy may have been accelerated since 1997. Based on our parameter estimates, we project 25% reduction in CO2 emissions by 2050 according to an economic and population growth scenario that is more consistent with recent global trends. Our forecasts are conservative due to that we do not have sufficient data to fully take into account recent developments in the global economy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Carbon Nanotube Electron Gun

    Science.gov (United States)

    Nguyen, Cattien V. (Inventor); Ribaya, Bryan P. (Inventor)

    2013-01-01

    An electron gun, an electron source for an electron gun, an extractor for an electron gun, and a respective method for producing the electron gun, the electron source and the extractor are disclosed. Embodiments provide an electron source utilizing a carbon nanotube (CNT) bonded to a substrate for increased stability, reliability, and durability. An extractor with an aperture in a conductive material is used to extract electrons from the electron source, where the aperture may substantially align with the CNT of the electron source when the extractor and electron source are mated to form the electron gun. The electron source and extractor may have alignment features for aligning the electron source and the extractor, thereby bringing the aperture and CNT into substantial alignment when assembled. The alignment features may provide and maintain this alignment during operation to improve the field emission characteristics and overall system stability of the electron gun.

  5. Nonstructural carbon in woody plants.

    Science.gov (United States)

    Dietze, Michael C; Sala, Anna; Carbone, Mariah S; Czimczik, Claudia I; Mantooth, Joshua A; Richardson, Andrew D; Vargas, Rodrigo

    2014-01-01

    Nonstructural carbon (NSC) provides the carbon and energy for plant growth and survival. In woody plants, fundamental questions about NSC remain unresolved: Is NSC storage an active or passive process? Do older NSC reserves remain accessible to the plant? How is NSC depletion related to mortality risk? Herein we review conceptual and mathematical models of NSC dynamics, recent observations and experiments at the organismal scale, and advances in plant physiology that have provided a better understanding of the dynamics of woody plant NSC. Plants preferentially use new carbon but can access decade-old carbon when the plant is stressed or physically damaged. In addition to serving as a carbon and energy source, NSC plays important roles in phloem transport, osmoregulation, and cold tolerance, but how plants regulate these competing roles and NSC depletion remains elusive. Moving forward requires greater synthesis of models and data and integration across scales from -omics to ecology.

  6. Natural materials for carbon capture.

    Energy Technology Data Exchange (ETDEWEB)

    Myshakin, Evgeniy M. (National Energy Technology Laboratory, Pittsburgh, PA); Romanov, Vyacheslav N. (National Energy Technology Laboratory, Pittsburgh, PA); Cygan, Randall Timothy

    2010-11-01

    Naturally occurring clay minerals provide a distinctive material for carbon capture and carbon dioxide sequestration. Swelling clay minerals, such as the smectite variety, possess an aluminosilicate structure that is controlled by low-charge layers that readily expand to accommodate water molecules and, potentially, carbon dioxide. Recent experimental studies have demonstrated the efficacy of intercalating carbon dioxide in the interlayer of layered clays but little is known about the molecular mechanisms of the process and the extent of carbon capture as a function of clay charge and structure. A series of molecular dynamics simulations and vibrational analyses have been completed to assess the molecular interactions associated with incorporation of CO2 in the interlayer of montmorillonite clay and to help validate the models with experimental observation.

  7. Proton and carbon ion therapy

    CERN Document Server

    Lomax, Tony

    2013-01-01

    Proton and Carbon Ion Therapy is an up-to-date guide to using proton and carbon ion therapy in modern cancer treatment. The book covers the physics and radiobiology basics of proton and ion beams, dosimetry methods and radiation measurements, and treatment delivery systems. It gives practical guidance on patient setup, target localization, and treatment planning for clinical proton and carbon ion therapy. The text also offers detailed reports on the treatment of pediatric cancers, lymphomas, and various other cancers. After an overview, the book focuses on the fundamental aspects of proton and carbon ion therapy equipment, including accelerators, gantries, and delivery systems. It then discusses dosimetry, biology, imaging, and treatment planning basics and provides clinical guidelines on the use of proton and carbon ion therapy for the treatment of specific cancers. Suitable for anyone involved with medical physics and radiation therapy, this book offers a balanced and critical assessment of state-of-the-art...

  8. Carbon nanotubes: engineering biomedical applications.

    Science.gov (United States)

    Gomez-Gualdrón, Diego A; Burgos, Juan C; Yu, Jiamei; Balbuena, Perla B

    2011-01-01

    Carbon nanotubes (CNTs) are cylinder-shaped allotropic forms of carbon, most widely produced under chemical vapor deposition. They possess astounding chemical, electronic, mechanical, and optical properties. Being among the most promising materials in nanotechnology, they are also likely to revolutionize medicine. Among other biomedical applications, after proper functionalization carbon nanotubes can be transformed into sophisticated biosensing and biocompatible drug-delivery systems, for specific targeting and elimination of tumor cells. This chapter provides an introduction to the chemical and electronic structure and properties of single-walled carbon nanotubes, followed by a description of the main synthesis and post-synthesis methods. These sections allow the reader to become familiar with the specific characteristics of these materials and the manner in which these properties may be dependent on the specific synthesis and post-synthesis processes. The chapter ends with a review of the current biomedical applications of carbon nanotubes, highlighting successes and challenges. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Chromium isotope uptake in carbonates

    DEFF Research Database (Denmark)

    Rodler, Alexandra

    retain an isotopically light Cr signature. Cr(VI) enriched in heavy Cr isotopes is then transported via river waters to the oceans and sequestered into marine sediments. Marine chemical sediments such asbanded iron formations and modern marine carbonates have proven useful in recording the Cr isotope...... with calcium carbonate in order to test the reliability of the Cr carbonate compositions. Several experimental approaches have been employed to elucidate the fractionation behavior of Cr isotopes when Cr(VI) is incorporated into calcium carbonate phases. These results indicate that at lower Cr concentrations......Chromium (Cr) is a redox sensitive element potentially capable of tracing fine-scale fluctuations of the oxygenation of Earth’s early surface environments and seawater. The Cr isotope composition of carbonates could perhaps be used as paleo-redox proxy to elucidate changes in the geological past...

  10. Carbon Nanostructures Containing Polyhedral Oligomeric Silsesquioxanes (POSS)

    NARCIS (Netherlands)

    Potsi, Georgia; Rossos, Andreas; Kouloumpis, Antonios; Antoniou, Myrsini K.; Spyrou, Konstantinos; Karakassides, Michael A.; Gournis, Dimitrios; Rudolf, Petra

    2015-01-01

    This mini review describes the synthesis and properties of carbon nanostructures containing organic-inorganic cage-like polyhedral oligomeric silsesquioxane (POSS). The physical and chemical functionalization of carbon nanomaterials such as graphene, graphene oxide, carbon nanotubes, and fullerenes

  11. Carbon sequestration in the agroecosystem

    Directory of Open Access Journals (Sweden)

    Tomáš Středa

    2008-01-01

    Full Text Available Reduction of amount CO2 is possible by carbon sequestration to the soil. Fixation potential of EU–15 agricultural land is c. 16–19 mil t C . year−1. Amount and composition of post–harvest residues is essential for carbon soil sequestration. Long–term yield series of the most planted crops (winter wheat – Triticum aestivum, spring barley – Hordeum vulgare, corn and silage maize – Zea mays, winter rape – Brassica napus, potatoes – Solanum tuberosum, sugar beet – Beta vulgaris, alfalfa – Medicago sativa, red clover – Trifolium pratense, white mustard – Sinapis alba and fiddleneck – Phacelia tanacetifolia in various agroecological conditions and growing technologies were used for carbon balance calculation. The carbon balances were calculated for main crop rotations of maize, sugar beet, cereal and potato production regions (24 crop rotations. The calculations were realized for following planting varieties: traditional, commercial, ecological and with higher rate of winter rape. All chosen crop rotations (except seven have positive carbon balance in the tillage system. Amount of fixed carbon might be increases about 30% by the use of no–tillage system. Least amount of carbon is fixed by potatoes, high amount by cereals, alfalfa and sugar beet. For a short time (months the crops sequestration of carbon is relatively high (to 4.4 t . ha−1 . year−1 or to 5.7 t . ha−1 . year−1 for no–tillage system. From the long time viewpoint (tens of years the data of humified carbon in arable soil (max 400 kg C . ha−1 . year−1 are important. Maximal carbon deficit of chosen crop rotation is 725 kg C . year−1.

  12. Carbon Nanotubes and Modern Nanoagriculture

    KAUST Repository

    Serag, Maged F.

    2015-01-27

    Since their discovery, carbon nanotubes have been prominent members of the nanomaterial family. Owing to their extraordinary physical, chemical, and mechanical properties, carbon nanotubes have been proven to be a useful tool in the field of plant science. They were frequently perceived to bring about valuable biotechnological and agricultural applications that still remain beyond experimental realization. An increasing number of studies have demonstrated the ability of carbon nanotubes to traverse different plant cell barriers. These studies, also, assessed the toxicity and environmental impacts of these nanomaterials. The knowledge provided by these studies is of practical and fundamental importance for diverse applications including intracellular labeling and imaging, genetic transformation, and for enhancing our knowledge of plant cell biology. Although different types of nanoparticles have been found to activate physiological processes in plants, carbon nanotubes received particular interest. Following addition to germination medium, carbon nanotubes enhanced root growth and elongation of some plants such as onion, cucumber and rye-grass. They, also, modulated the expression of some genes that are essential for cell division and plant development. In addition, multi-walled carbon nanotubes were evidenced to penetrate thick seed coats, stimulate germination, and to enhance growth of young tomato seedlings. Multi-walled carbon nanotubes can penetrate deeply into the root system and further distribute into the leaves and the fruits. In recent studies, carbon nanotubes were reported to be chemically entrapped into the structure of plant tracheary elements. This should activate studies in the fields of plant defense and wood engineering. Although, all of these effects on plant physiology and plant developmental biology have not been fully understood, the valuable findings promises more research activity in the near future toward complete scientific understanding of

  13. Optimal decisions of countries with carbon tax and carbon tariff

    Directory of Open Access Journals (Sweden)

    Yumei Hou

    2015-05-01

    Full Text Available Purpose: Reducing carbon emission has been the core problem of controlling global warming and climate deterioration recently. This paper focuses on the optimal carbon taxation policy levied by countries and the impact on firms’ optimal production decisions. Design/methodology/approach: This paper uses a two-stage game theory model to analyze the impact of carbon tariff and tax. Numerical simulation is used to supplement the theoretical analysis. Findings: Results derived from the paper indicate that the demand in an unstable market is significantly affected by environmental damage level. Carbon tariff is a policy-oriented tax while the carbon tax is a market-oriented one. Comprehensive carbon taxation policy benefit developed countries and basic policy is more suitable for developing countries. Research limitations/implications: In this research, we do not consider random demand and asymmetric information, which may not well suited the reality. Originality/value: This work provides a different perspective in analyzing the impact of carbon tax and tariff. It is the first study to consider two consuming market and the strategic game between two countries. Different international status of countries considered in the paper is also a unique point.

  14. Thallium in the marine environment: first ecotoxicological assessments in the Guadalquivir estuary and its potential adverse effect on the donana european natural reserve after the Aznalcollar mining spill (SW Spain); Talio en el medio marino: primera valoracion ecotoxicologica en el estuario del Guadalquivir y su efecto potencial adverso en la reserva natural de donana despues del vertido minero de Aznalcollar (SW de Espana).

    Energy Technology Data Exchange (ETDEWEB)

    DelValls, T.A [Departamento de Quimica Fisica, Facultad de Ciencias del Mar, Universidad de Cadiz, Puerto Real, Cadiz (Spain); Saenz, V; Arias, A.M; Blasco, J [Instituto de Ciencias Marinas de Andalucia, CSIC, Puerto Real, Cadiz (Spain)

    1999-06-01

    Thallium (Tl) is an extremely toxic but little-studied element in the marine environment and practically no information has been reported on the levels of Tl in marine organisms. After the Aznalcollar mining Spill (April 1998), high levels of metals were put into the environment. This acud-contaminated medium was responsible for the initial pollution effects measured in the Guadiamar River, which is an affluent of the Guadalquivir River and very close to the biggest natural reserve in Europe (Donana). Four different species were used in the monitoring from April to September 1998 and a sediment field bioassay to check bioacumulation was performed. We present the first ecotoxicological evaluation of the mining spill in the Guadalquivir River, with reference to Tl, a little-known metal. Also, Pb and Cd data were compared to Tl during field sediment testing. Results show low levels of this metal in all of the organisms studied and they do not show any increase in the level of this metal, ranging from 40 to 90 ng g{sup -}1, 80 to 210 ng g{sup -}1, 15 to 98 ng g{sup -}1 and 75 to 125 whole body dry weight for Scrobicularia plana, Liza ramada (muscle), Crassostrea angulata and Uca Tangeri, respectively. These are the first field data of Tl concentration measured using estuarine organisms. Field sediment toxicity test results confirm those obtained during the monitoring: Tl is not bioaccumulated by the organisms (C. angulata) used in the test. The sequence in bioaccumulation of metals was Cd > Pb > Tl. Both studies, bioaccumulation and sediment toxicity, should be maintained during the next few years to really evaluate the potential effect of the mining spill on the ecosystem and society. [Spanish] El talio (Tl) es un elemento extremadamente toxico aunque poco estudiado en el medio marino y la informacion sobre niveles de Tl en organismos marinos con anterioridad al presente trabajo es practicamente nula. Despues del vertido minero de Aznalcollar (abril de 1998) se

  15. Nanophase Carbonates on Mars: Implications for Carbonate Formation and Habitability

    Science.gov (United States)

    Archer, P. Douglas, Jr.; Lauer, H. Vern; Ming, Douglas W.; Niles, Paul B.; Morris, Richard V.; Rampe, Elizabeth B.; Sutter, Brad

    2014-01-01

    Despite having an atmosphere composed primarily of CO2 and evidence for abundant water in the past, carbonate minerals have only been discovered in small amounts in martian dust [1], in outcrops of very limited extent [2, 3], in soils in the Northern Plains (the landing site of the 2007 Phoenix Mars Scout Mission) [4] and may have recently been detected in aeolian material and drilled and powdered sedimentary rock in Gale Crater (the Mars Science Laboratory [MSL] landing site) [5]. Thermal analysis of martian soils by instruments on Phoenix and MSL has demonstrated a release of CO2 at temperatures as low as 250-300 degC, much lower than the traditional decomposition temperatures of calcium or magnesium carbonates. Thermal decomposition temperature can depend on a number of factors such as instrument pressure and ramp rate, and sample particle size [6]. However, if the CO2 released at low temperatures is from carbonates, small particle size is the only effect that could have such a large impact on decomposition temperature, implying the presence of extremely fine-grained (i.e., "nanophase" or clay-sized) carbonates. We hypothesize that this lower temperature release is the signature of small particle-sized (clay-sized) carbonates formed by the weathering of primary minerals in dust or soils through interactions with atmospheric water and carbon dioxide and that this process may persist under current martian conditions. Preliminary work has shown that clay-sized carbonate grains can decompose at much lower temperatures than previously thought. The first work took carbonate, decomposed it to CaO, then flowed CO2 over these samples held at temperatures >100 degC to reform carbonates. Thermal analysis confirmed that carbonates were indeed formed and transmission electron microsopy was used to determine crystal sized were on the order of 10 nm. The next step used minerals such as diopside and wollastonite that were sealed in a glass tube with a CO2 and H2O source. After

  16. Uncovering the Neoproterozoic carbon cycle.

    Science.gov (United States)

    Johnston, D T; Macdonald, F A; Gill, B C; Hoffman, P F; Schrag, D P

    2012-02-29

    Interpretations of major climatic and biological events in Earth history are, in large part, derived from the stable carbon isotope records of carbonate rocks and sedimentary organic matter. Neoproterozoic carbonate records contain unusual and large negative isotopic anomalies within long periods (10-100 million years) characterized by δ(13)C in carbonate (δ(13)C(carb)) enriched to more than +5 per mil. Classically, δ(13)C(carb) is interpreted as a metric of the relative fraction of carbon buried as organic matter in marine sediments, which can be linked to oxygen accumulation through the stoichiometry of primary production. If a change in the isotopic composition of marine dissolved inorganic carbon is responsible for these excursions, it is expected that records of δ(13)C(carb) and δ(13)C in organic carbon (δ(13)C(org)) will covary, offset by the fractionation imparted by primary production. The documentation of several Neoproterozoic δ(13)C(carb) excursions that are decoupled from δ(13)C(org), however, indicates that other mechanisms may account for these excursions. Here we present δ(13)C data from Mongolia, northwest Canada and Namibia that capture multiple large-amplitude (over 10 per mil) negative carbon isotope anomalies, and use these data in a new quantitative mixing model to examine the behaviour of the Neoproterozoic carbon cycle. We find that carbonate and organic carbon isotope data from Mongolia and Canada are tightly coupled through multiple δ(13)C(carb) excursions, quantitatively ruling out previously suggested alternative explanations, such as diagenesis or the presence and terminal oxidation of a large marine dissolved organic carbon reservoir. Our data from Namibia, which do not record isotopic covariance, can be explained by simple mixing with a detrital flux of organic matter. We thus interpret δ(13)C(carb) anomalies as recording a primary perturbation to the surface carbon cycle. This interpretation requires the revisiting of

  17. faas determination of thallium after preconcentration using nitroso-s ...

    African Journals Online (AJOL)

    EXPERIMENTAL. Apparatus. A Shimadzu AA-670 flame atomic absorption spectrophotometer was used in the following conditions: wavelength: 276.8 nm, lamp ... hydrogen phosphate and 0.1 M sodium dihydrogen phosphate and 0.5 M aqueous ammonia and ... The residue was dried at the room temperature in the folds.

  18. Thallium-201 accumulation in cerebral candidiasis: Unexpected finding on SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Tonami, N.; Matsuda, H.; Ooba, H.; Yokoyama, K.; Hisada, K.; Ikeda, K.; Yamashita, J. (Kanazawa Univ. (Japan))

    1990-06-01

    The authors present an unexpected finding of Tl-201 uptake in the intracerebral lesions due to candidiasis. SPECT demonstrated the extent of the lesions and a high target-to-background ratio. The regions where abnormal Tl-201 accumulation was seen were nearly consistent with CT scans of those enhanced by a contrast agent. After treatment, most of the abnormal Tl-201 accumulation disappeared.

  19. Thallium Toxicity: The Problem; An Analytical Approach; An Antidotal Study

    Science.gov (United States)

    1993-05-15

    Nixon CE: The 1932 thallotoxi- cosis outbreak in California. JAMA 100:1315-1319, 1933. 21. Aoyama H, Yoshida M, Yamamura Y: Acute poisoning by...lower extremities); ataxia; muscle/joint pain; aptosis; strabismis; facial palsy; mydriasis; psychotic signs (permanent neurological and psychiatric

  20. Sequential thallium-201 myocardial scintigraphy after acute infarction in man

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, J.W.; Mueller, H.S.; Rao, P.S.

    1980-07-01

    Three sequential Tl-201 myocardial perfusion studies were performed in 21 patients (18 men, 3 women) with first acute transmural myocardia infarction. The Tl-201 image defect size was determined with a semiquantitative visual scoring method and temporal changes in image defect size were compared to CK-MB infarct size and enzymatic evidence of progressive myocardial necrosis and infarct extension. Progressive decreases in Tl-201 image defect size were observed and the visual score in all 21 patients decreased significantly from 6.5 +- 3.7 (mean +- SD) on day 1 to 4.9 +- 3.5 on day 12. Eleven patients without evidence of infarct extension had significantly lower infarct size, a significant decrease in visual score by the 12th day and had significantly smaller Tl-201 defects at all three study times compared to 10 patients with infarct extension. Seven of 10 (70%) with extension had an initial visual score greater than or equal to 7 compared to only 2/11 (18%) without extension. The temporal behavior of Tl-201 image defects is related to the size of the infarction and presence or absence of extension. Sequential studies comparing early initial and subsequent defect size may assist in evaluating the behavior of ischemic and infarcted myocardium in the postinfarction period.

  1. A comparison of the clinical relevance of thallium- 201 and ...

    African Journals Online (AJOL)

    1990-09-01

    Sep 1, 1990 ... group of 20 patients, who underwent both 201TI single photon emission computed tomography and 99mTc_MIBI study as well as coronary angiography. The sensitivity for predicting a lesion ranged from 25% to 88% in different areas of the heart and was comparable for the two radiophannaceuticals. The.

  2. Thallium isotope variations in anthropogenically-affected soils

    Science.gov (United States)

    Vanek, Ales; Chrastny, Vladislav; Penizek, Vit; Mihaljevic, Martin; Komarek, Michael; Cabala, Jerzy

    2014-05-01

    Our preliminary data from soils impacted by long-term Tl deposition in the vicinity of a primary/secondary Zn smelter at Olkusz (Poland) indicate apparent variability of ɛ205Tl within soil profiles. The identified ɛ205Tl values presented for the forest soil profile reached -1.7 in the surface/organic horizon, +1.9 in the organo-mineral horizon (Ap), and +1.0 in the mineral horizon (C). This finding suggests both the enrichment of 203Tl isotope in the topsoil, as well as its preferential release during smelting operations, as "lighter" Tl tends to enter the emissions during a high-temperature process. The maximum ɛ205Tl value in the subsurface horizon Ap is in accordance with the concentration peak of oxalate-extractable Mn, indicating the presence of amorphous/poorly-crystalline Mn oxides with a potential to isotopically fractionate Tl toward the "heavier" fraction. The Tl isotope signature in the bottom horizon probably reflects the composition of a local geochemical anomaly of Tl. However, a portion of mobile (anthropogenic) Tl with negative ɛ205Tl moving downwards in the soil profile cannot be neglected. In general, there is no detailed information about the biogeochemical cycling and variations of Tl isotopes in areas affected by significant anthropogenic inputs of the metal (e.g., coal burning and primary metallurgy); the questions of the degree to which the factors such as soil (and sediment) chemistry, mineralogy, local biota, and pollution source control Tl isotope fractionation remain unresolved. Therefore, further research on the topic is needed before any principal conclusions will be made.

  3. TYPE Ia SUPERNOVA CARBON FOOTPRINTS

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, R. C.; Nugent, P. [Computational Cosmology Center, Computational Research Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road MS 50B-4206, Berkeley, CA 94611 (United States); Aldering, G.; Aragon, C.; Bailey, S.; Childress, M.; Fakhouri, H. K.; Hsiao, E. Y.; Loken, S. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A. [Laboratoire de Physique Nucleaire et des Hautes Energies, Universite Pierre et Marie Curie Paris 6, Universite Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, 75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Kerschhaggl, M.; Kowalski, M.; Paech, K. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, 53115 Bonn (Germany); Chotard, N.; Copin, Y.; Gangler, E. [Universite de Lyon, F-69622 Lyon (France); and others

    2011-12-10

    We present convincing evidence of unburned carbon at photospheric velocities in new observations of five Type Ia supernovae (SNe Ia) obtained by the Nearby Supernova Factory. These SNe are identified by examining 346 spectra from 124 SNe obtained before +2.5 days relative to maximum. Detections are based on the presence of relatively strong C II {lambda}6580 absorption 'notches' in multiple spectra of each SN, aided by automated fitting with the SYNAPPS code. Four of the five SNe in question are otherwise spectroscopically unremarkable, with ions and ejection velocities typical of SNe Ia, but spectra of the fifth exhibit high-velocity (v > 20, 000 km s{sup -1}) Si II and Ca II features. On the other hand, the light curve properties are preferentially grouped, strongly suggesting a connection between carbon-positivity and broadband light curve/color behavior: three of the five have relatively narrow light curves but also blue colors and a fourth may be a dust-reddened member of this family. Accounting for signal to noise and phase, we estimate that 22{sup +10}{sub -6%} of SNe Ia exhibit spectroscopic C II signatures as late as -5 days with respect to maximum. We place these new objects in the context of previously recognized carbon-positive SNe Ia and consider reasonable scenarios seeking to explain a physical connection between light curve properties and the presence of photospheric carbon. We also examine the detailed evolution of the detected carbon signatures and the surrounding wavelength regions to shed light on the distribution of carbon in the ejecta. Our ability to reconstruct the C II {lambda}6580 feature in detail under the assumption of purely spherical symmetry casts doubt on a 'carbon blobs' hypothesis, but does not rule out all asymmetric models. A low volume filling factor for carbon, combined with line-of-sight effects, seems unlikely to explain the scarcity of detected carbon in SNe Ia by itself.

  4. The NASA Carbon Monitoring System

    Science.gov (United States)

    Hurtt, G. C.

    2015-12-01

    Greenhouse gas emission inventories, forest carbon sequestration programs (e.g., Reducing Emissions from Deforestation and Forest Degradation (REDD and REDD+), cap-and-trade systems, self-reporting programs, and their associated monitoring, reporting and verification (MRV) frameworks depend upon data that are accurate, systematic, practical, and transparent. A sustained, observationally-driven carbon monitoring system using remote sensing data has the potential to significantly improve the relevant carbon cycle information base for the U.S. and world. Initiated in 2010, NASA's Carbon Monitoring System (CMS) project is prototyping and conducting pilot studies to evaluate technological approaches and methodologies to meet carbon monitoring and reporting requirements for multiple users and over multiple scales of interest. NASA's approach emphasizes exploitation of the satellite remote sensing resources, computational capabilities, scientific knowledge, airborne science capabilities, and end-to-end system expertise that are major strengths of the NASA Earth Science program. Through user engagement activities, the NASA CMS project is taking specific actions to be responsive to the needs of stakeholders working to improve carbon MRV frameworks. The first phase of NASA CMS projects focused on developing products for U.S. biomass/carbon stocks and global carbon fluxes, and on scoping studies to identify stakeholders and explore other potential carbon products. The second phase built upon these initial efforts, with a large expansion in prototyping activities across a diversity of systems, scales, and regions, including research focused on prototype MRV systems and utilization of COTS technologies. Priorities for the future include: 1) utilizing future satellite sensors, 2) prototyping with commercial off-the-shelf technology, 3) expanding the range of prototyping activities, 4) rigorous evaluation, uncertainty quantification, and error characterization, 5) stakeholder

  5. Atmospheric carbon dioxide and the global carbon cycle

    Energy Technology Data Exchange (ETDEWEB)

    Trabalka, J R [ed.

    1985-12-01

    This state-of-the-art volume presents discussions on the global cycle of carbon, the dynamic balance among global atmospheric CO2 sources and sinks. Separate abstracts have been prepared for the individual papers. (ACR)

  6. Studies on Enhancing Transverse Thermal Conductivity Carbon/Carbon Composites

    National Research Council Canada - National Science Library

    Manocha, Lalit M; Manocha, Satish M; Roy, Ajit

    2007-01-01

    The structure derived potential properties of Graphite such as high stiffness coupled with high thermal conductivity and low coefficient of thermal expansion have been better achieved in Carbon fibers...

  7. Carbon budgets and carbon sequestration potential of Indian forests

    NARCIS (Netherlands)

    Kaul, M.

    2010-01-01

    Keywords: Carbon uptake, Forest biomass, Bioenergy, Land use change, Indian forests, Deforestation, Afforestation, Rotation length, Trees outside forests. Global climate change is a widespread and growing concern that has led to extensive international discussions and negotiations. Responses to

  8. Method for carbon dioxide splitting

    Science.gov (United States)

    Miller, James E.; Diver, Jr., Richard B.; Siegel, Nathan P.

    2017-02-28

    A method for splitting carbon dioxide via a two-step metal oxide thermochemical cycle by heating a metal oxide compound selected from an iron oxide material of the general formula A.sub.xFe.sub.3-xO.sub.4, where 0.ltoreq.x.ltoreq.1 and A is a metal selected from Mg, Cu, Zn, Ni, Co, and Mn, or a ceria oxide compound of the general formula M.sub.aCe.sub.bO.sub.c, where 0gas mixture, adding carbon dioxide, and heating to a temperature less than approximately 1400 C, thereby producing carbon monoxide gas and the original metal oxide compound.

  9. From PAHs to Solid Carbon

    Science.gov (United States)

    Jäger, C.; Mutschke, H.; Henning, T.; Huisken, F.

    2011-03-01

    Carbonaceous grains represent a major component of cosmic dust. The review will summarize new results in laboratory investigations of carbonaceous dust components. The nanometer-sized carbon particles are supposed to represent a blend of differently structured carbon including graphitic, diamond-like, fullerene-like and chain-like components on a subnanometer or nanometer scale. Recent models used to explain the structure of gas-phase condensed carbon nano-particles are discussed. Possible formation pathways of carbonaceous grains from molecular components and clusters and the role of polycyclic aromatic hydrocarbons (PAHs) and fullerenes are disclosed.

  10. Capacitor with a composite carbon foam electrode

    Science.gov (United States)

    Mayer, S.T.; Pekala, R.W.; Kaschmitter, J.L.

    1999-04-27

    Carbon aerogels used as a binder for granularized materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy. 1 fig.

  11. Oxidation resistant carbon-carbon composite for Space Shuttle application.

    Science.gov (United States)

    Rogers, D. C.; Seeger, J. W.; Shuford, D. M.

    1973-01-01

    An oxidation resistant carbon-carbon composite has been developed for use on the NASA Space Shuttle Orbiter Vehicle which can function on the high temperature surfaces to satisfy the 100 mission reuse capability requirement. This paper describes the design requirements, materials and processes developed, and the successful testing of simulated full-scale prototype hardware. Materials considerations are illustrated, including strength and oxidation testing, along with physical property determinations, characterizing the material over the predicted temperature range of use.

  12. Carbon-carbon turbopump concept for Space Nuclear Thermal Propulsion

    Science.gov (United States)

    Overholt, David M.

    1993-06-01

    The U.S. Air Force Space Nuclear Thermal Propulsion (SNTP) program is placing high priority on maximizing specific impulse (ISP) and thrust-to-weight ratio in the development of a practical high-performance nuclear rocket. The turbopump design is driven by these goals. The liquid hydrogen propellant is pressurized and pumped to the reactor inlet by the turbopump assembly (TPA). Rocket propulsion is from rapid heating of the propellant from 180 R to thousands of degrees in the particle bed reactor (PBR). The exhausted propellant is then expanded through a high-temperature nozzle. A high-performance approach is to use an uncooled carbon-carbon nozzle and duct turbine inlet. Carbon-carbon components are used throughout the TPA hot section to obtain the high-temperature capability. Several carbon-carbon components are in development including structural parts, turbine nozzles/stators, and turbine rotors. The technology spinoff is applicable to conventional liquid propulsion engines and many other turbomachinery applications.

  13. Carbon isotopes in biological carbonates: Respiration and photosynthesis

    Science.gov (United States)

    McConnaughey, Ted A.; Burdett, Jim; Whelan, Joseph F.; Paull, Charles K.

    1997-02-01

    Respired carbon dioxide is an important constituent in the carbonates of most air breathing animals but is much less important in the carbonates of most aquatic animals. This difference is illustrated using carbon isotope data from freshwater and terrestrial snails, ahermatypic corals, and chemoautotrophic and methanotrophic pelecypods. Literature data from fish otoliths and bird and mammal shell and bone carbonates are also considered. Environmental CO 2/O 2 ratios appear to be the major controlling variable. Atmospheric CO 2/O 2 ratios are about thirty times lower than in most natural waters, hence air breathing animals absorb less environmental CO 2 in the course of obtaining 0 2. Tissue CO 2 therefore, does not isotopically equilibrate with environmental CO 2 as thoroughly in air breathers as in aquatic animals, and this is reflected in skeletal carbonates. Animals having efficient oxygen transport systems, such as vertebrates, also accumulate more respired CO 2 in their tissues. Photosynthetic corals calcify mainly during the daytime when photosynthetic CO 2 uptake is several times faster than respiratory CO 2 release. Photosynthesis, therefore, affects skeletal δ13C more strongly than does respiration. Corals also illustrate how "metabolic" effects on skeletal isotopic composition can be estimated, despite the presence of much larger "kinetic" isotope effects.

  14. Universally dispersible carbon nanotubes.

    Science.gov (United States)

    Prevoteau, Alexandre; Soulié-Ziakovic, Corinne; Leibler, Ludwik

    2012-12-12

    We show that supramolecular chemistry provides a convenient tool to prepare carbone nanotubes (CNTs) that can be dispersed in solvents of any chemical nature, easily recovered and redispersed. Thymine-modified CNTs (CNT-Thy) can be dispersed in solution in the presence of diaminotriazine (DAT) end-functionalized polymers, through supramolecular Thy/DAT association. DAT-polymer chains are selected according to the solvent chemical nature: polystyrene (PS) for hydrophobic/low polarity solvents and a propylene oxide/ethylene oxide copolymer (predominantly propylene oxide based, PPO/PEO) for polar solvents or water. Long-term stable supramolecular CNT dispersions are reversibly aggregated by adding a few droplets of a selective dissociating agent of the Thy/DAT association (DMSO). CNT-Thy, simply recycled by centrifugation or filtration, can be redispersed in another solvent in presence of a suitable soluble DAT-polymer. Dispersion and aggregation can also be switched on and off by choosing a polymer for which a given solvent is close to Θ-conditions, e.g., PS in cyclohexane or PPO/PEO in water.

  15. Carbon flows, carbon markets, and low-carbon lifestyles: reflecting on the role of markets in climate governance

    NARCIS (Netherlands)

    Spaargaren, G.; Mol, A.P.J.

    2013-01-01

    The role of carbon markets in governing global carbon flows triggers substantial debates among policymakers, social movements and social scientists. The present debate on carbon markets is different from the earlier debate on market-based instruments in environmental politics. Carbon markets

  16. Hypervelocity impact resistance of reinforced carbon carbon/carbon foam thermal protection systems

    Science.gov (United States)

    Grujicic, M.; Pandurangan, B.; Zhao, C. L.; Biggers, S. B.; Morgan, D. R.

    2006-05-01

    Common aero vehicles (CAVs) are aerodynamically designed, (from orbit) re-entry, un-powered military vehicles planned to be used for deployment of the desired munitions with increased accuracy and range. In one of the currently considered designs of the CAVs, their outer skin is planned to be constructed from two-ply panels. The outer play is made of a carbon-carbon composite while the inner ply is constructed from a carbon-based foam. In the present work a transient non-linear-dynamics-based analysis is carried out in order to predict the extent of damage and the probability for failure of the carbon-carbon/carbon-foam CAV panels during potential hypervelocity impact of space debris with the outer surface of the CAVs. The results obtained show that the extent of damage scales with the normal component of the momentum associated with the debris particles just before the impact. In addition, it is found that despite its relatively low strength, the carbon-foam can provide a major increase in the resistance of the CAV panels towards penetration of the hypervelocity debris particles. This finding has been linked with an attendant consolidation of the foam, the process that is capable of absorbing a substantial amount of kinetic energy carried by the debris particles.

  17. Method for making carbon films

    Science.gov (United States)

    Tan, M.X.

    1999-07-29

    A method for treating an organic polymer material, preferably a vinylidene chloride/vinyl chloride copolymer (Saran) to produce a flat sheet of carbon film material having a high surface area ([approx equal]1000 m[sup 2] /g) suitable as an electrode material for super capacitor applications. The method comprises heating a vinylidene chloride/vinyl chloride copolymer film disposed between two spaced apart graphite or ceramic plates to a first temperature of about 160 C for about 14 hours to form a stabilized vinylidene chloride/vinyl chloride polymer film, thereafter heating the stabilized film to a second temperature of about 750 C in an inert atmosphere for about one hour to form a carbon film; and finally activating the carbon film to increase the surface area by heating the carbon film in an oxidizing atmosphere to a temperature of at least 750--850 C for between 1--6 hours. 2 figs.

  18. ROE Carbon Storage - Forest Biomass

    Data.gov (United States)

    U.S. Environmental Protection Agency — This polygon dataset depicts the density of forest biomass in counties across the United States, in terms of metric tons of carbon per square mile of land area....

  19. Enhanced Carbon Nanotube Ultracapacitors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation utilizes carbon nanotubes (CNTs) coated with pseudo-capacitive MnO2 material as nano-composite electrode and ionic electrolyte for the...

  20. Mirador - Carbon Cycle and Ecosystems

    Data.gov (United States)

    National Aeronautics and Space Administration — Earth Science data access made simple. This Focus Area deals with the cycling of carbon in reservoirs and ecosystems as it changes naturally, is changed by humans,...

  1. Assimilation of Unusual Carbon Compounds

    Science.gov (United States)

    Middelhoven, Wouter J.

    Yeast taxa traditionally are distinguished by growth tests on several sugars and organic acids. During the last decades it became apparent that many yeast species assimilate a much greater variety of naturally occurring carbon compounds as sole source of carbon and energy. These abilities are indicative of a greater role of yeasts in the carbon cycle than previously assumed. Especially in acidic soils and other habitats, yeasts may play a role in the degradation of carbon compounds. Such compounds include purines like uric acid and adenine, aliphatic amines, diamines and hydroxyamines, phenolics and other benzene compounds and polysaccharides. Assimilation of purines and amines is a feature of many ascomycetes and basidiomycetes. However, benzene compounds are degraded by only a few ascomycetous yeasts (e.g. the Stephanoascus/ Blastobotrys clade and black yeastlike fungi) but by many basidiomycetes, e.g. Filobasidiales, Trichosporonales, red yeasts producing ballistoconidia and related species, but not by Tremellales. Assimilation of polysaccharides is wide-spread among basidiomycetes

  2. Carbon Fiber Technology Facility (CFTF)

    Data.gov (United States)

    Federal Laboratory Consortium — Functionally within the MDF, ORNL operates DOE’s unique Carbon Fiber Technology Facility (CFTF)—a 42,000 ft2 innovative technology facility and works with leading...

  3. The process of carbon creation

    CERN Multimedia

    El-Eid, M F

    2005-01-01

    In the Universe, the element carbon is created only in stars, in a remarkable reaction called the triple-α process. Fresh insights into the reaction now come from the latest experiments carried out on Earth

  4. Magnesite disposal of carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Lackner, K.S.; Butt, D.P.; Wendt, C.H.

    1997-08-01

    In this paper we report our progress on developing a method for carbon dioxide disposal whose purpose it is to maintain coal energy competitive even is environmental and political pressures will require a drastic reduction in carbon dioxide emissions. In contrast to most other methods, our approach is not aiming at a partial solution of the problem, or at buying time for phasing out fossil energy. Instead, its purpose is to obtain a complete and economic solution of the problem, and thus maintain access to the vast fossil energy reservoir. A successful development of this technology would guarantee energy availability for many centuries even if world economic growth the most optimistic estimates that have been put forward. Our approach differs from all others in that we are developing an industrial process which chemically binds the carbon dioxide in an exothermic reaction into a mineral carbonate that is thermodynamically stable and environmentally benign.

  5. Transparent, Conductive Carbon Nanotube Films

    National Research Council Canada - National Science Library

    Zhuangchun Wu; Zhihong Chen; Xu Du; Jonathan M. Logan; Jennifer Sippel; Maria Nikolou; Katalin Kamaras; John R. Reynolds; David B. Tanner; Arthur F. Hebard; Andrew G. Rinzler

    2004-01-01

    We describe a simple process for the fabrication of ultrathin, transparent, optically homogeneous, electrically conducting films of pure single-walled carbon nanotubes and the transfer of those films...

  6. High capacity carbon dioxide sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, Steven Dean; Alptekin, Gokhan; Jayaraman, Ambalavanan

    2015-09-01

    The present invention provides a sorbent for the removal of carbon dioxide from gas streams, comprising: a CO.sub.2 capacity of at least 9 weight percent when measured at 22.degree. C. and 1 atmosphere; an H.sub.2O capacity of at most 15 weight percent when measured at 25.degree. C. and 1 atmosphere; and an isosteric heat of adsorption of from 5 to 8.5 kilocalories per mole of CO.sub.2. The invention also provides a carbon sorbent in a powder, a granular or a pellet form for the removal of carbon dioxide from gas streams, comprising: a carbon content of at least 90 weight percent; a nitrogen content of at least 1 weight percent; an oxygen content of at most 3 weight percent; a BET surface area from 50 to 2600 m.sup.2/g; and a DFT micropore volume from 0.04 to 0.8 cc/g.

  7. Reducing carbon dioxide to products

    Science.gov (United States)

    Cole, Emily Barton; Sivasankar, Narayanappa; Parajuli, Rishi; Keets, Kate A

    2014-09-30

    A method reducing carbon dioxide to one or more products may include steps (A) to (C). Step (A) may bubble said carbon dioxide into a solution of an electrolyte and a catalyst in a divided electrochemical cell. The divided electrochemical cell may include an anode in a first cell compartment and a cathode in a second cell compartment. The cathode may reduce said carbon dioxide into said products. Step (B) may adjust one or more of (a) a cathode material, (b) a surface morphology of said cathode, (c) said electrolyte, (d) a manner in which said carbon dioxide is bubbled, (e), a pH level of said solution, and (f) an electrical potential of said divided electrochemical cell, to vary at least one of (i) which of said products is produced and (ii) a faradaic yield of said products. Step (C) may separate said products from said solution.

  8. Stable carbon, nitrogen and sulfur isotopes in non-carbonate fractions of cold-seep carbonates

    Science.gov (United States)

    Feng, Dong; Peng, Yongbo; Peckmann, Jörn; Roberts, Harry; Chen, Duofu

    2017-04-01

    Sulfate-driven anaerobic oxidation of methane (AOM) supports chemosynthesis-based communities and limits the release of methane from marine sediments. This process promotes the formation of carbonates close to the seafloor along continental margins. The geochemical characteristics of the carbonate minerals of these rocks are increasingly understood, questions remain about the geochemical characteristics of the non-carbonate fractions. Here, we report stable carbon, nitrogen and sulfur isotope patterns in non-carbonate fractions of seep carbonates. The authigenic carbonates were collected from three modern seep provinces (Black Sea, Gulf of Mexico, and South China Sea) and three ancient seep deposits (Marmorito, northern Italy, Miocene; SR4 deposit of the Lincoln Creek Formation and Whiskey Creek, western Washington, USA, Eocene to Oligocene). The δ13C values of non-carbonate fractions range from ˜-25‰ to -80‰ VPDB. These values indicate that fossil methane mixed with varying amounts of pelagic organic matter is the dominant source of carbon in these fractions. The relatively small offset between the δ34S signatures of the non-carbonate fractions and the respective sulfide minerals suggests that locally produced hydrogen sulfide is the main source of sulfur in seep environments. The δ15N values of the non-carbonate fractions are generally lower than the corresponding values of deep-sea sediments, suggesting that organic nitrogen is mostly of a local origin. This study reveals the potential of using δ13C, δ15N, δ34S values to discern seep and non-seep deposits. In cases where δ13Ccarbonate values are only moderately low due to mixing processes and lipid biomarkers have been erased in the course of burial, it is difficult to trace back AOM owing to the lack of other records. This problem is even more pronounced when authigenic carbonate is not available in ancient seep environments. Acknowledgments: The authors thank BOEM and NOAA for their years' support

  9. New way to trap carbon

    Science.gov (United States)

    2015-06-01

    In reply to the physicsworld.com news story “How to efficiently capture carbon dioxide out of thin air” (16 April, http://ow.ly/LHvpz; see also p4), which described a novel synthetic resin that can capture carbon dioxide (CO2) and remove it from the atmosphere much faster than trees can. The article noted that the resin absorbs CO2 in dry air and releases it again in humid air.

  10. Carbon Nanotubes and Related Structures

    OpenAIRE

    Kingsuk Mukhopadhyay; Kanik Ram; K.U. Bhasker Rao

    2008-01-01

    Carbon nanotubes have attracted the fancy of many scientists world wide. The small dimensions,strength, and the remarkable physical properties of these structures make them a unique material with a whole range of promising applications. In this review, the structural aspects, the advantages and disadvantages of different for their procedures synthesis, the qualitative and quantitative estimation of carbon nanotubes by different analytical techniques, the present status on their applications a...

  11. Carbon nanotubes for coherent spintronics

    DEFF Research Database (Denmark)

    Kuemmeth, Ferdinand; Churchill, H O H; Herring, P K

    2010-01-01

    Carbon nanotubes bridge the molecular and crystalline quantum worlds, and their extraordinary electronic, mechanical and optical properties have attracted enormous attention from a broad scientific community. We review the basic principles of fabricating spin-electronic devices based on individual......, electrically-gated carbon nanotubes, and present experimental efforts to understand their electronic and nuclear spin degrees of freedom, which in the future may enable quantum applications....

  12. Selective functionalization of carbon nanotubes

    Science.gov (United States)

    Strano, Michael S. (Inventor); Usrey, Monica (Inventor); Barone, Paul (Inventor); Dyke, Christopher A. (Inventor); Tour, James M. (Inventor); Kittrell, W. Carter (Inventor); Hauge, Robert H. (Inventor); Smalley, Richard E. (Inventor)

    2009-01-01

    The present invention is directed toward methods of selectively functionalizing carbon nanotubes of a specific type or range of types, based on their electronic properties, using diazonium chemistry. The present invention is also directed toward methods of separating carbon nanotubes into populations of specific types or range(s) of types via selective functionalization and electrophoresis, and also to the novel compositions generated by such separations.

  13. Electrolytic formation of carbon nanostructures

    Science.gov (United States)

    Hsu, W. K.; Terrones, M.; Hare, J. P.; Terrones, H.; Kroto, H. W.; Walton, D. R. M.

    1996-11-01

    Carbon nanotubes (with and without encapsulated material) as well as nanoparticles and onion-like structures have been generated by electrolysis in molten alkali halide salts using carbon electrodes under an argon atmosphere. The nature of the products depends upon several factors including the electrolysis voltage and current, depth of electrode immersion in the electrolyte, the length of time the current is maintained and the electrolyte.

  14. Toward transformational carbon capture systems

    Energy Technology Data Exchange (ETDEWEB)

    Miller, David C. [National Energy Technology Laboratory, U.S. Dept. of Energy, Pittsburgh PA (United States); Litynski, John T. [Office of Fossil Energy, U.S. Dept. of Energy, Washington DC (United States); Brickett, Lynn A. [National Energy Technology Laboratory, U.S. Dept. of Energy, Pittsburgh PA (United States); Morreale, Bryan D. [National Energy Technology Laboratory, U.S. Dept. of Energy, Pittsburgh PA (United States)

    2015-10-28

    This paper will briefly review the history and current state of Carbon Capture and Storage (CCS) research and development and describe the technical barriers to carbon capture. it will argue forcefully for a new approach to R&D, which leverages both simulation and physical systems at the laboratory and pilot scales to more rapidly move the best technoogies forward, prune less advantageous approaches, and simultaneously develop materials and processes.

  15. Lithographically defined microporous carbon structures

    Science.gov (United States)

    Burckel, David Bruce; Washburn, Cody M.; Polsky, Ronen; Brozik, Susan M.; Wheeler, David R.

    2013-01-08

    A lithographic method is used to fabricate porous carbon structures that can provide electrochemical electrodes having high surface area with uniform and controllable dimensions, providing enormous flexibility to tailor the electrodes toward specific applications. Metal nanoparticles deposited on the surface of the porous carbon electrodes exhibit ultra small dimensions with uniform size distribution. The resulting electrodes are rugged, electrically conductive and show excellent electrochemical behavior.

  16. Recuperative supercritical carbon dioxide cycle

    Science.gov (United States)

    Sonwane, Chandrashekhar; Sprouse, Kenneth M; Subbaraman, Ganesan; O'Connor, George M; Johnson, Gregory A

    2014-11-18

    A power plant includes a closed loop, supercritical carbon dioxide system (CLS-CO.sub.2 system). The CLS-CO.sub.2 system includes a turbine-generator and a high temperature recuperator (HTR) that is arranged to receive expanded carbon dioxide from the turbine-generator. The HTR includes a plurality of heat exchangers that define respective heat exchange areas. At least two of the heat exchangers have different heat exchange areas.

  17. Method for carbon dioxide sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yifeng; Bryan, Charles R.; Dewers, Thomas; Heath, Jason E.

    2017-12-05

    A method for geo-sequestration of a carbon dioxide includes selection of a target water-laden geological formation with low-permeability interbeds, providing an injection well into the formation and injecting supercritical carbon dioxide (SC-CO.sub.2) and water or bine into the injection well under conditions of temperature, pressure and density selected to cause the fluid to enter the formation and splinter and/or form immobilized ganglia within the formation.

  18. A Pentagon Based Carbon Sheet

    Science.gov (United States)

    Wang, Qian; Zhang, Shunhong; Zhou, Jian; Chen, Xiaoshuang; Kawazoe, Yoshiyuki; Jena, Puru; A international Team Collaboration

    2015-03-01

    A new two-dimensional (2D) meta-stable carbon allotrope, penta-graphene, composed entirely of carbon pentagons and resembling the Cairo pentagonal tiling, is proposed. State-of-the-art theoretical calculations confirm that the new carbon polymorph is not only dynamically and mechanically stable, but also can withstand temperatures as high as 1000 K. Due to its unique atomic configuration penta-graphene has an unusual negative Poisson's ratio (NPR) and ultra-high ideal strength that can even outperform graphene. Furthermore, unlike graphene that needs to be functionalized for opening a band gap, penta-graphene possesses an intrinsic quasi-direct band gap as large as 3.25 eV - close to that of ZnO and GaN. Equally important, when rolled up, penta-graphene can form a pentagon-based nanotube. The resulting penta-carbon nanotubes are semiconducting regardless of their chirality. When stacked in different patterns, dynamically and thermally stable 3D twin structures of T12-carbon are generated with band gaps even larger than that of T12-carbon. The versatility of penta-graphene and its derivatives are expected to have broad applications in nanoelectronics and nanomechanics. Peking University.

  19. Carbon-enhanced VRLA batteries.

    Energy Technology Data Exchange (ETDEWEB)

    Enos, David George; Hund, Thomas D.; Shane, Rod (East Penn Manufacturing, Lyon Station, PA)

    2010-10-01

    The addition of certain forms of carbon to the negative plate in valve regulated lead acid (VRLA) batteries has been demonstrated to increase the cycle life of such batteries by an order of magnitude or more under high-rate, partial-state-of-charge operation. Such performance will provide a significant impact, and in some cases it will be an enabling feature for applications including hybrid electric vehicles, utility ancillary regulation services, wind farm energy smoothing, and solar photovoltaic energy smoothing. There is a critical need to understnd how the carbon interacts with the negative plate and achieves the aforementioned benefits at a fundamental level. Such an understanding will not only enable the performance of such batteries to be optimzied, but also to explore the feasibility of applying this technology to other battery chemistries. In partnership with the East Penn Manufacturing, Sandia will investigate the electrochemical function of the carbon and possibly identify improvements to its anti-sulfation properties. Shiomi, et al. (1997) discovered that the addition of carbon to the negative active material (NAM) substantially reduced PbSO{sub 4} accumulation in high rate, partial state of charge (HRPSoC) cycling applications. This improved performance with a minimal cost. Cycling applications that were uneconomical for traditional VRLA batteries are viable for the carbon enhanced VRLA. The overall goal of this work is to quantitatively define the role that carbon plays in the electrochemistry of a VRLA battery.

  20. Carbon monoxide: Anticoagulant or procoagulant?

    Science.gov (United States)

    Nielsen, Vance G; Pretorius, Etheresia

    2014-03-01

    Within the past decade there have been several investigations attempting to define the impact of exogenous and endogenous carbon monoxide exposure on hemostasis. Critically, two bodies of literature have emerged, with carbon monoxide mediated platelet inhibition cited as a cause of in vitro human and in vitro/in vivo rodent anticoagulation. In contrast, interaction with heme groups associated with fibrinogen, α₂-antiplasmin and plasmin by carbon monoxide has resulted in enhanced coagulation and decreased fibrinolysis in vitro in human and other species, and in vivo in rabbits. Of interest, the ultrastructure of platelet rich plasma thrombi demonstrates an abnormal increase in fine fiber formation and matting that are obtained from humans exposed to carbon monoxide. Further, thrombi obtained from humans and rabbits have very similar ultrastructures, whereas mice and rats have more fine fibers and matting present. In sum, there may be species specific differences with regard to hemostatic response to carbon monoxide. Carbon monoxide may be a Janus-faced molecule, with potential to attenuate or exacerbate thrombophilic disease. Copyright © 2013 Elsevier Ltd. All rights reserved.