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Sample records for activated charcoal sample

  1. Activated Charcoal

    MedlinePlus

    ... ACTIVATED CHARCOAL are as follows:Trapping chemicals to stop some types of poisoning when used as a ... Charbon Végétal, Charbon Végétal Activé, Charcoal, Gas Black, Lamp Black, Medicinal Charcoal, Noir de Gaz, Noir de ...

  2. Activated Charcoal

    MedlinePlus

    ... is used to treat poisonings, reduce intestinal gas (flatulence), lower cholesterol levels, prevent hangover, and treat bile ... lower cholesterol levels in the blood. Decreasing gas (flatulence). Some studies show that activated charcoal is effective ...

  3. Passivation of fluorinated activated charcoal

    SciTech Connect

    Del Cul, G.D.; Trowbridge, L.D.; Simmons, D.W.; Williams, D.F.; Toth, L.M.

    1997-10-01

    The Molten Salt Reactor Experiment (MSRE), at the Oak Ridge National Laboratory has been shut down since 1969 when the fuel salt was drained from the core into two Hastelloy N tanks at the reactor site. In 1995, a multiyear project was launched to remediate the potentially hazardous conditions generated by the movement of fissile material and reactive gases from the storage tanks into the piping system and an auxiliary charcoal bed (ACB). The top 12 in. of the ACB is known by gamma scan and thermal analysis to contain about 2.6 kg U-233. According to the laboratory tests, a few feet of fluorinated charcoal are believed to extend beyond the uranium front. The remainder of the ACB should consist of unreacted charcoal. Fluorinated charcoal, when subjected to rapid heating, can decompose generating gaseous products. Under confined conditions, the sudden exothermic decomposition can produce high temperatures and pressures of near-explosive characteristics. Since it will be necessary to drill and tap the ACB to allow installation of piping and instrumentation for remediation and recovery activities, it is necessary to chemically convert the reactive fluorinated charcoal into a more stable material. Ammonia can be administered to the ACB as a volatile denaturing agent that results in the conversion of the C{sub x}F to carbon and ammonium fluoride, NH{sub 4}F. The charcoal laden with NH{sub 4}F can then be heated without risking any sudden decomposition. The only consequence of heating the treated material will be the volatilization of NH{sub 4}F as a mixture of NH{sub 3} and HF, which would primarily recombine as NH{sub 4}F on surfaces below 200 C. The planned scheme for the ACB denaturing is to flow diluted ammonia gas in steps of increasing NH{sub 3} concentration, 2% to 50%, followed by the injection of pure ammonia. This report summarizes the planned passivation treatment scheme to stabilize the ACB and remove the potential hazards. It also includes basic information

  4. Effect of activated charcoal on the pharmacokinetics of pholcodine, with special reference to delayed charcoal ingestion.

    PubMed

    Laine, K; Kivistö, K T; Ojala-Karlsson, P; Neuvonen, P J

    1997-02-01

    We conducted a randomized study with four parallel groups to investigate the effect of single and multiple doses of activated charcoal on the absorption and elimination of pholcodine administered in a cough syrup. The first group received 100 mg of pholcodine on an empty stomach with water only (control); the second group took 25 g of activated charcoal immediately after pholcodine; the third group received 25 g of activated charcoal 2 h and the fourth group 5 h after ingestion of the 100-mg dose of pholcodine. In addition, the fourth group received multiple doses (10 g each) of charcoal every 12 h for 84 h. Blood samples were collected for 96 h and urine for 72 h. Pholcodine concentrations were measured by high-performance liquid chromatography. A significant reduction in absorption was found when charcoal was administered immediately after pholcodine; the AUC0-96h was reduced by 91% (p < 0.0005), the Cmax by 77% (p < 0.0005), and the amount of pholcodine excreted into urine by 85% (p < 0.0005). When charcoal was administered 2 h after pholcodine, the AUC0-96h was reduced by 26% (p = 0.002), the Cmax by 23% (p = NS), and the urinary excretion by 28% (p = 0.004). When administered 5 h after pholcodine, charcoal produced only a 17% reduction in the AUC0-96h (p = 0.06), but reduced the further absorption of pholcodine still present in the gastrointestinal tract at the time of charcoal administration, as measured by AUC5-96h (p = 0.006). Repeated administration of charcoal failed to accelerate the elimination of pholcodine. We conclude that activated charcoal is effective in preventing the absorption of pholcodine, and its administration can be beneficial even several hours after pholcodine ingestion. PMID:9029746

  5. Activated coconut shell charcoal carbon using chemical-physical activation

    NASA Astrophysics Data System (ADS)

    Budi, Esmar; Umiatin, Nasbey, Hadi; Bintoro, Ridho Akbar; Wulandari, Futri; Erlina

    2016-02-01

    The use of activated carbon from natural material such as coconut shell charcoal as metal absorbance of the wastewater is a new trend. The activation of coconut shell charcoal carbon by using chemical-physical activation has been investigated. Coconut shell was pyrolized in kiln at temperature about 75 - 150 °C for about 6 hours in producing charcoal. The charcoal as the sample was shieved into milimeter sized granule particle and chemically activated by immersing in various concentration of HCl, H3PO4, KOH and NaOH solutions. The samples then was physically activated using horizontal furnace at 400°C for 1 hours in argon gas environment with flow rate of 200 kg/m3. The surface morphology and carbon content of activated carbon were characterized by using SEM/EDS. The result shows that the pores of activated carbon are openned wider as the chemical activator concentration is increased due to an excessive chemical attack. However, the pores tend to be closed as further increasing in chemical activator concentration due to carbon collapsing.

  6. Charcoal and activated carbon at elevated pressure

    SciTech Connect

    Antal, M.J. Jr.; Dai, Xiangfeng; Norberg, N.

    1995-12-01

    High quality charcoal has been produced with very high yields of 50% to 60% from macadamia nut and kukui nut shells and of 44% to 47% from Eucalyptus and Leucaena wood in a bench scale unit at elevated pressure on a 2 to 3 hour cycle, compared to commercial practice of 25% to 30% yield on a 7 to 12 day operating cycle. Neither air pollution nor tar is produced by the process. The effects of feedstock pretreatments with metal additives on charcoal yield are evaluated in this paper. Also, the influences of steam and air partial pressure and total pressure on yields of activated carbon from high yield charcoal are presented.

  7. Comparison of Impurities in Charcoal Sorbents Found by Neutron Activation Analysis

    SciTech Connect

    Doll, Charles G.; Finn, Erin C.; Cantaloub, Michael G.; Greenwood, Lawrence R.; Kephart, Jeremy; Kephart, Rosara F.

    2013-01-01

    Abstract: Neutron activation of gas samples in a reactor often requires a medium to retain sufficient amounts of the gas for analysis. Charcoal is commonly used to adsorb gas and hold it for activation; however, the amount of activated sodium in the charcoal after irradiation swamps most signals of interest. Neutron activation analysis (NAA) was performed on several commonly available charcoal samples in an effort to determine the activation background. The results for several elements, including the dominant sodium element, are reported. It was found that ECN charcoal had the lowest elemental background, containing sodium at 2.65 ± 0.05 ppm, as well as trace levels of copper and tungsten.

  8. [Paraquat poisoning and hemoperfusion with activated charcoal].

    PubMed

    López Lago, A M; Rivero Velasco, C; Galban Rodríguez, C; Mariño Rozados, A; Piñeiro Sande, N; Ferrer Vizoso, E

    2002-06-01

    Paraquat is a common herbicide in Spain. In our country there are a few cases of this intoxication and it presents a high mortality even if the patients ingest a minimal amount. We present two cases of accidental poisoning with paraquat. These patients were admitted three hours after ingestion of toxin. They were treated with with orogastric lavage, activated charcoal, N-acetylcysteine, Fuller's earth, cathartics, support measures and hemoperfusion with activated charcoal. With these treatments both patients had a undetectable levels of paraquat 48 hours after and improvement of their symptoms, gastric and intestinal predominantly . We present the graphics of evolution of the plasma and urine levels of paraquat in both patients. We review the different aspects of treatment and update of this poisoning. PMID:12152392

  9. Post-Flight Sampling and Loading Characterization of Trace Contaminant Control Subassembly Charcoal

    NASA Technical Reports Server (NTRS)

    Perry, J. L.; Cole, H. E.; Cramblitt, E. L.; El-Lessy, H. N.; Manuel, S.; Tucker, C. D.

    2003-01-01

    Trace chemical contaminants produced by equipment offgassing and human metabolic processes are removed from the atmosphere of the International Space Station s U.S. Segment by a trace contaminant control subassembly (TCCS). The TCCS employs a combination of physical adsorption, thermal catalytic oxidation, and chemical adsorption processes to accomplish its task. A large bed of granular activated charcoal is a primary component of the TCCS. The charcoal contained in this bed, known as the charcoal bed assembly (CBA), is expendable and must be replaced periodically. Pre-flight engineering analyses based upon TCCS performance testing results established a service life estimate of 1 year. After nearly 1 year of cumulative in-flight operations, the first CBA was returned for refurbishment. Charcoal samples were collected and analyzed for loading to determine the best estimate for the CBAs service life. A history of in-flight TCCS operations is presented as well as a discussion of the charcoal sampling procedures and chemical analysis results. A projected service life derived from the observed charcoal loading is provided. Recommendations for better managing TCCS resources are presented.

  10. Calibration of diffusion barrier charcoal detectors and application to radon sampling in dwellings

    NASA Astrophysics Data System (ADS)

    Cabrera, M. E. M.; Sujo, L. C.; Villalba, L.; Peinado, J. S.; Jimenez, A. C.; Baca, A. M.; Gandara, S. D.; Villalobos, M. R.; Miranda, A. L.; Peraza, E. F. H.

    2003-10-01

    Some calibration conditions of diffusion barrier charcoal canister (DBCC) detectors for measuring radon concentration in air were studied. A series of functional expressions and graphs were developed to describe relationship between radon concentration in air and the activity adsorbed in DBCC, when placed in small chambers. A semi-empirical expression for the DBCC calibration was obtained, based on the detector integration time and the adsorption coefficient of radon on activated charcoal. Both, the integration time for 10% of DBCC of the same batch, and the adsorption coefficient of radon for the activated charcoal used in these detectors, were experimentally determined. Using these values as the calibration parameters, a semi-empirical calibration function was used for the interpretation of the radon activities in the detectors used for sampling more than 200 dwellings in the major cities of the state of Chihuahua, Mexico.

  11. Contaminant breakthrough: A theoretical study of charcoal sampling tubes

    SciTech Connect

    Yoon, Y.H.; Nelson, J.H. )

    1990-06-01

    A previously developed theoretical model was applied to investigate contaminant breakthrough on charcoal sampling tubes. Associated with the model are two important theoretical parameters. These parameters are k' (a rate constant) and tau (the time required for 50% contaminant breakthrough). In this study, values of K' and tau were determined for n-heptane at five different concentration levels in air: 98, 117, 234, 330, and 988 ppm. These values were used along with pertinent theoretical considerations to calculate the entire (0-100%) breakthrough curve (plot of percent breakthrough versus time) regarding the adsorbance of n-heptane on charcoal sampling tubes. In addition, available experimental data for perchloroethylene, isobutyl acetate, ethyl acetate, and dichloromethane were used in conjunction with the theory to generate theoretical breakthrough curves over the entire range of 0 to 100%. In each case, calculated theoretical breakthrough curves are in remarkable agreement with corresponding experimental data. With the use of an additional theoretical parameter, a, the theory was extended to calculate the weight of contaminant collected on a single element (section) of a charcoal sampling tube at 10% breakthrough and at each of several different contaminant assault concentrations.

  12. Charcoal produced by prescribed fire increases dissolved organic carbon and soil microbial activity

    NASA Astrophysics Data System (ADS)

    Poon, Cheryl; Jenkins, Meaghan; Bell, Tina; Adams, Mark

    2014-05-01

    In Australian forests fire is an important driver of carbon (C) storage. When biomass C is combusted it is transformed into vegetation residue (charcoal) and deposited in varying amounts and forms onto soil surfaces. The C content of charcoal is high but is largely in a chemically stable form of C, which is highly resistance to microbial decomposition. We conducted two laboratory incubations to examine the influence of charcoal on soil microbial activity as indicated by microbial respiration. Seven sites were chosen in mixed species eucalypt forest in Victoria, Australia. Soil was sampled prior to burning to minimise the effects of heating or addition of charcoal during the prescribed burn. Charcoal samples were collected from each site after the burn, homogenised and divided into two size fractions. Prior to incubation, soils were amended with the two size fractions (<1 and 1-4.75 mm) and at two rates of amount (2.5 and 5% by soil dry weight). Charcoal-amended soils were incubated in the laboratory for 86 d, microbial respiration was measured nine times at day 1, 3, 8, 15, 23, 30, 45, 59 and 86 d. We found that addition of charcoal resulted in faster rates of microbial respiration compared to unamended soil. Fastest rates of microbial respiration in all four treatments were measured 1 d after addition of charcoal (up to 12 times greater than unamended soil). From 3 to 8 d, respiration rates in all four treatments decreased and only treatments with greater charcoal addition (5%) remained significantly faster than unamended soil. From 15 d to 86 d, all treatments had respiration rates similar to unamended soil. Overall, adding greater amount of charcoal (5%) resulted in a larger cumulative amount of CO2 released over the incubation period when compared to unamended soil. The second laboratory incubation focused on the initial changes in soil nutrient and microbial respiration after addition of charcoal over a 72 h period. Charcoal (<2 mm) was added at rate of 5% to

  13. Activated charcoal for acute overdose: a reappraisal.

    PubMed

    Juurlink, David N

    2016-03-01

    Sometimes mistakenly characterized as a 'universal antidote,' activated charcoal (AC) is the most frequently employed method of gastrointestinal decontamination in the developed world. Typically administered as a single dose (SDAC), its tremendous surface area permits the binding of many drugs and toxins in the gastrointestinal lumen, reducing their systemic absorption. Like other decontamination procedures, the utility of SDAC attenuates with time, and, although generally safe, it is not free of risk. A large body of evidence demonstrates that SDAC can reduce the absorption of drugs and xenobiotics but most such studies involve volunteers and have little generalizability to clinical practice. Few rigorous clinical trials of SDAC have been conducted, and none validate or refute its utility in those patients who are intuitively most likely to benefit. Over the past decade, a growing body of observational data have demonstrated that SDAC can elicit substantial reductions in drug absorption in acutely poisoned patients. The challenge for clinicians rests in differentiating those patients most likely to benefit from SDAC from those in whom meaningful improvement is doubtful. This is often a difficult determination not well suited to an algorithmic approach. The present narrative review summarizes the data supporting the benefits and harms of SDAC, and offers pragmatic suggestions for clinical practice. PMID:26409027

  14. Prehospital activated charcoal: the way forward

    PubMed Central

    Greene, S; Kerins, M; O'Connor, N

    2005-01-01

    Methods: A postal questionnaire was used to determine the current level of use of prehospital activated charcoal by ambulance NHS trusts, the incidence of associated complications, and barriers preventing the routine use of prehospital SDAC. Results: A completed questionnaire was returned by 36 of the 39 ambulance NHS trusts in the UK (response rate 92%). Currently none of the trusts that responded to the questionnaire provides prehospital SDAC as an intervention. The most common barriers to the provision of prehospital SDAC are the current lack of evidence in the medical literature proving it is effective in improving patient outcome and the lack of a recognised protocol for its administration. Other issues included concerns regarding potential complications, ambulance turnaround times, lack of availability of SDAC, and lack of funding. Conclusions: A lack of published evidence proving efficacy remains the most important factor in preventing the routine administration of SDAC to appropriate patients in the prehospital environment. Further research in this setting is required to determine the usefulness of this therapy. PMID:16189043

  15. Production of charcoal and activated carbon at elevated pressure

    SciTech Connect

    Dai, Xiangfeng; Norberg, N.; Antal, M.J. Jr.

    1995-12-31

    With its wide range of properties, charcoal finds many commercial applications for domestic cooking, refining of metals (steel, copper, bronze, nickel, aluminum and electro-manganese), production of chemicals (carbon disulfide, calcium carbide, silicon carbide, sodium cyanide, carbon black, fireworks, gaseous chemicals, absorbents, soil conditioners and pharmaceuticals), as well as production of activated carbon and synthesis gas. In 1991, the world production of charcoal was 22.8 million cubic meters (3.8 million metric tons) as shown in Table 1. Brazil is the world`s largest charcoal producer --- 5.9 million cubic meters or one million metric tons was produced in 1991, most of which is used in steel and iron industry. African countries produced 45% of the world total amount of charcoal, where 86% of the wood-based energy is for domestic use, most of which is inefficiently used. Charcoal is produced commercially in kilns with a 25% to 30% yield by mass on a 7 to 12 day operating cycle. Until recently, the highest yield of good quality charcoal reported in the literature was 38%. In this paper, and ASME code rated experimental system is presented for producing charcoal and activated carbon from biomass.

  16. Fluorine gettering by activated charcoal in a radiation environment

    SciTech Connect

    Felker, L.K.; Toth, L.M.

    1988-10-01

    Activated charcoal has been shown to be an effective gettering agent for the fluorine gas that is liberated in a radiation environment. Even though activated charcoal is a commonly used getter, little is known about the radiation stability of the fluorine-charcoal product. This work has shown that not only is the product stable in high gamma radiation fields, but also that radiation enhances the capacity of the charcoal for the fluorine. The most useful application of this work is with the Molten Salt Reactor Experiment (MSRE) fuel salt because the radioactive components (fission products and actinides) cause radiolytic damage to the solid LiF-BeF/sub 2/-ZrF/sub 4/-UF/sub 4/ (64.5, 30.3, 5.0, 0.13 mol %, respectively) resulting in the liberation of fluorine gas. This work has also demonstrated that the maximum damage to the fuel salt by approx.3 /times/ 10/sup 7/ R/h gamma radiation is approximately 2%, at which point the rate of recombination of fluorine with active metal sites within the salt lattice equals the rate of fluorine generation. The enhanced reactivity of the activated charcoal and radiation stability of the product ensures that the gettered fluorine will stay sequestered in the charcoal.

  17. Relative efficacy and palatability of three activated charcoal mixtures.

    PubMed

    Navarro, R P; Navarro, K R; Krenzelok, E P

    1980-02-01

    The addition of bentonite with or without chocolate syrup improved the palatability of activated charcoal preparations. Furthermore, bentonite did not significantly reduce the efficacy of charcoal to absorb aspirin. Chocolate syrup reduced the adsorption effectiveness significantly. The mixtures have a reduced shelf-life when premixed with water. However, the dry ingredients can be pre-weighed and sealed in a large jar. Water can be added just prior to administration. PMID:7361450

  18. Recovery and Determination of Adsorbed Technetium on Savannah River Site Charcoal Stack Samples

    SciTech Connect

    Lahoda, Kristy G.; Engelmann, Mark D.; Farmer, Orville T.; Ballou, Nathan E.

    2008-03-01

    Experimental results are provided for the sample analyses for technetium (Tc) in charcoal samples placed in-line with a Savannah River Site (SRS) processing stack effluent stream as a part of an environmental surveillance program. The method for Tc removal from charcoal was based on that originally developed with high purity charcoal. Presented is the process that allowed for the quantitative analysis of 99Tc in SRS charcoal stack samples with and without 97Tc as a tracer. The results obtained with the method using the 97Tc tracer quantitatively confirm the results obtained with no tracer added. All samples contain 99Tc at the pg g-1 level.

  19. Pore structure of the activated coconut shell charcoal carbon

    NASA Astrophysics Data System (ADS)

    Budi, E.; Nasbey, H.; Yuniarti, B. D. P.; Nurmayatri, Y.; Fahdiana, J.; Budi, A. S.

    2014-09-01

    The development of activated carbon from coconut shell charcoal has been investigated by using physical method to determine the influence of activation parameters in term of temperature, argon gas pressure and time period on the pore structure of the activated carbon. The coconut shell charcoal was produced by pyrolisis process at temperature of about 75 - 150 °C for 6 hours. The charcoal was activated at various temperature (532, 700 and 868 °C), argon gas pressure (6.59, 15 and 23.4 kgf/cm2) and time period of (10, 60 and 120 minutes). The results showed that the pores size were reduced and distributed uniformly as the activation parameters are increased.

  20. Using Macroscopic Charcoal to Reconstruct the Holocene Fire Activity of the Willamette Valley, Oregon and Washington

    NASA Astrophysics Data System (ADS)

    Walsh, M. K.; Whitlock, C.; Bartlein, P. J.; Pearl, C. A.

    2006-12-01

    High-resolution macroscopic charcoal analysis of two lacustrine records has revealed the Holocene fire activity of the Willamette Valley, located between the Coast and Cascade ranges of southwestern Washington and northwestern Oregon. The Willamette Valley experienced major environmental and cultural changes during the Holocene, however, its long-term fire history is poorly known. Of particular interest are shifts in fire activity that occurred in response to (1) millennial- and centennial-scale climate and vegetation changes (e.g., the Early Holocene warm period, the Little Ice Age) and (2) major shifts in human activity and population size (e.g., Native American population decline, Euro-American settlement). Macroscopic charcoal analysis of contiguous core samples was used to reconstruct fire activity at each site. Charcoal source (i.e., herbaceous or woody) was also determined based on particle morphology. Charcoal influx was decomposed into a peak component (which indicates fire episodes) and a background component (which indicates changes in burnable biomass). Charcoal records from Battle Ground Lake and Beaver Lake reveal major shifts in fire activity that are consistent with known changes in regional climate on orbital time scales. The Battle Ground Lake charcoal data, for example, show a general increase in fire frequency from the beginning of the Holocene to a maximum of ~18 fire episodes/1000 years at 6500 cal yr BP, associated with the early Holocene insolation maximum and its influence on summer drought, followed by a decrease to ~5 fire episodes/1000 years at present. Similar trends are indicated by the Beaver Lake charcoal data. Both records also indicate shifts in fire activity that suggest the possibility of anthropogenic burning, but at different times at each site. Additional records are being analyzed to examine the spatial and temporal patterns of fire activity across the Willamette Valley as a whole.

  1. In vitro analysis of the effect of supplementation with activated charcoal on the equine hindgut

    PubMed Central

    EDMUNDS, J.L.; WORGAN, H.J.; DOUGAL, K.; GIRDWOOD, S.E.; DOUGLAS, J.-L.; MCEWAN, N.R.

    2016-01-01

    ABSTRACT The present study uses in vitro analytical techniques to investigate the effect of activated charcoal on the microbial community of the equine hindgut and the metabolites they produce. Incubations were performed in Wheaton bottles using a 50 ml incubation of a high-energy feed or a low-energy feed, plus bottles with no added food source, together with five levels of activated charcoal (0, 10, 25, 50 or 100 mg per bottle) and fecal samples as a bacterial inoculum. Using this method the rate of gas production, volatile fatty acid and ammonia concentrations, and pH values were analyzed and found to vary depending on the addition of feed, but the activated charcoal had no effect (P>0.05) on any of these. It is already believed that the effect of activated charcoal as a control for toxic substances is at its highest in the foregut or midgut of animals, and therefore should have little impact on the hindgut. The data presented here suggest that if any of the activated charcoal does reach the hindgut, then it has no significant impact on the microbial community present, nor on the major metabolites produced, and so should not have a detrimental effect on the principal site of fermentation in the horse. PMID:27330398

  2. In vitro analysis of the effect of supplementation with activated charcoal on the equine hindgut.

    PubMed

    Edmunds, J L; Worgan, H J; Dougal, K; Girdwood, S E; Douglas, J-L; McEwan, N R

    2016-01-01

    The present study uses in vitro analytical techniques to investigate the effect of activated charcoal on the microbial community of the equine hindgut and the metabolites they produce. Incubations were performed in Wheaton bottles using a 50 ml incubation of a high-energy feed or a low-energy feed, plus bottles with no added food source, together with five levels of activated charcoal (0, 10, 25, 50 or 100 mg per bottle) and fecal samples as a bacterial inoculum. Using this method the rate of gas production, volatile fatty acid and ammonia concentrations, and pH values were analyzed and found to vary depending on the addition of feed, but the activated charcoal had no effect (P>0.05) on any of these. It is already believed that the effect of activated charcoal as a control for toxic substances is at its highest in the foregut or midgut of animals, and therefore should have little impact on the hindgut. The data presented here suggest that if any of the activated charcoal does reach the hindgut, then it has no significant impact on the microbial community present, nor on the major metabolites produced, and so should not have a detrimental effect on the principal site of fermentation in the horse. PMID:27330398

  3. The role of activated charcoal in plant tissue culture.

    PubMed

    Thomas, T Dennis

    2008-01-01

    Activated charcoal has a very fine network of pores with large inner surface area on which many substances can be adsorbed. Activated charcoal is often used in tissue culture to improve cell growth and development. It plays a critical role in micropropagation, orchid seed germination, somatic embryogenesis, anther culture, synthetic seed production, protoplast culture, rooting, stem elongation, bulb formation etc. The promotary effects of AC on morphogenesis may be mainly due to its irreversible adsorption of inhibitory compounds in the culture medium and substancially decreasing the toxic metabolites, phenolic exudation and brown exudate accumulation. In addition to this activated charcoal is involved in a number of stimulatory and inhibitory activities including the release of substances naturally present in AC which promote growth, alteration and darkening of culture media, and adsorption of vitamins, metal ions and plant growth regulators, including abscisic acid and gaseous ethylene. The effect of AC on growth regulator uptake is still unclear but some workers believe that AC may gradually release certain adsorbed products, such as nutrients and growth regulators which become available to plants. This review focuses on the various roles of activated charcoal in plant tissue culture and the recent developments in this area. PMID:18786626

  4. Activated charcoal. (Latest citations from the Compendex database). Published Search

    SciTech Connect

    Not Available

    1993-06-01

    The bibliography contains citations concerning theoretical aspects and industrial applications of activated charcoal. Topics include adsorption capacity and mechanism studies, kinetic and thermodynamic aspects, and description and evaluation of adsorptive abilities. Applications include use in water analyses and waste treatment, air pollution control and measurement, and in nuclear facilities. (Contains a minimum of 151 citations and includes a subject term index and title list.)

  5. Replacement of charcoal sorbent in the VOST

    SciTech Connect

    Johnson, L.D.; Fuerst, R.G.; Foster, A.L.; Bursey, J.T.

    1993-01-01

    EPA Method 0030, the Volatile Organic Sampling Train (VOST), for sampling volatile organics from stationary sources, specifies the use of petroleum-base charcoal in the second sorbent tube. Charcoal has proven to be a marginal performer as a sampling sorbent, partly due to inconsistency in analyte recovery. In addition, commercial availability of petroleum charcoal for VOST tubes has been variable. Lack of data on comparability and variability of charcoals for VOST application has created uncertainty when other charcoals are substituted. Five potential sorbent replacements for charcoal in Method 0030 were evaluated along with a reference charcoal. Two of the sorbents tested, Ambersorb XE-340 and Tenax GR, did not perform well enough to qualify as replacements. Three candidates, Anasorb 747, Carbosieve S-III and Kureha Beaded Activated Charcoal, performed adequately, and produced statistically equivalent results. Anasorb 747 appears to be an acceptable replacement for petroleum charcoal, based on a combination of performance, availability, and cost.

  6. Assessment of the elution of charcoal, cellulose acetate, and other particles from cigarettes with charcoal and activated charcoal/resin filters.

    PubMed

    Agyei-Aye, K; Appleton, S; Rogers, R A; Taylor, C R

    2004-08-01

    This experiment was designed to study the release of cellulose acetate fibers, charcoal, and other particles from cigarettes with charcoal and activated charcoal/resin filters. For the first time in such studies, efforts were made to identify the particles that were eluted using other analytical techniques in addition to light microscopy. Other corrective measures were also implemented. During the studies it was found that trimming of larger filters to fit smaller filter housings introduced cellulose acetate-like particles from the fibers of the filter material. Special, custom made-to-fit filters were used instead. Tools such as forceps that were used to retrieve filters from their housings were also found to introduce fragments onto the filters. It is believed that introduction of such debris may have accounted for the very large number of cellulose acetate and charcoal particles that had been reported in the literature. Use of computerized particle-counting microscopes appeared to result in excessive number of particles. This could be because the filter or smoke pads used for such work do not have the flat and level surfaces ideal for computerized particle-counting microscopes. At the high magnifications that the pads were viewed for particles, constant focusing of the microscope would be essential. It was also found that determination of total particles by using extrapolation of particle count by grid population usually gave extremely high particle counts compared to the actual number of particles present. This could be because particle distributions during smoking are not uniform. Lastly, a less complex estimation of the thickness of the particles was adopted. This and the use of a simple mathematical conversion coupled with the Cox equation were utilized to assess the aerodynamic diameters of the particles. Our findings showed that compared to numbers quoted in the literature, only a small amount of charcoal, cellulose acetate shards, and other particles are

  7. Effect of thermal treatments on the properties of nickel and cobalt activated-charcoal-supported catalysts

    SciTech Connect

    Gandia, L.M.; Montes, M. )

    1994-02-01

    The effect of thermal pretreatment in N[sub 2] up to 723 K and the activation treatments in H[sub 2] and an inert atmosphere on the properties of Ni and Co activated-charcoal-supported catalysts were studied. Catalysts were characterized by means of N[sub 2] adsorption at 77 K, H[sub 2] chemisorption at room temperature, thermogravimetric analysis (TGA), X-ray diffraction (XRD), and transmission electron microscopy (TEM). The catalysts' activity and selectivity for acetone hydrogenation to 2-propanol under unusual and severe conditions (473 K and high overall acetone conversion) were also measured. TGA and XRD evidence was found for the charcoal-support-promoted NiO and CoO reduction to the metallic states when the catalysts were subjected to an inert atmosphere above 723 K caused a loss of acetone hydrogenation activity (calculated on a metal load basis) for both the Ni and Co activated-charcoal-supported catalysts, with respect to that of the low-temperature (573 K) activation treatments. In a series of activated-charcoal-supported Ni catalysts, a large decrease in the H[sub 2] chemisorption uptake was also found for a sample pretreated in N[sub 2] at 723 K prior to H[sub 2] reduction. These results were not due to nickel or cobalt sintering, as shown by XRD line broadening measurements. The catalytic activity loss was accompanied by a decrease (in the case of Ni) and an increase (in the case of Co) in the 2-propanol selectivity. 44 refs., 13 figs., 3 tabs.

  8. Tri (2-chloroisopropyl) phosphate--an unexpected organochlorine contaminant in some charcoal air-sampling sorbent tubes

    SciTech Connect

    van Netten, C.; Brands, R.; Park, J.; Deverall, R. )

    1991-09-01

    Air sampling in a government building was necessary in response to reports of a cancer cluster. SKC (Eighty Four, Pa.) charcoal coconut shell-based sorbent tubes (226-01 lot 120) were recommended for this procedure. A recently purchased supply was present at the University of British Columbia and consequently was used for this particular study. Analysis of the front charcoal section showed the presence of a flame retardant, tri (2-chloroisopropyl) phosphate, which was confirmed by gas liquid chromatography (GLC) and mass spectrometry analysis. In an effort to identify the source of this fire retardant in the building, it became apparent from the analysis done on unknown field blanks that tri (2-chloroisopropyl) phosphate was a contaminant of the sorbent tubes used. Analysis of additional blank tubes identified the foam separators as the most likely source of contamination. Levels of tri (2-chloroisopropyl) phosphate in the front charcoal section ranged from 1.3 to 5.9 micrograms. The foam separator contained between 11.4 and 16.5 micrograms, and the backup charcoal section contained between 14.5 and 24.0 micrograms of tri (2-chloroisopropyl) phosphate. In addition, another flame retardant, tri (1,3 dichloro-2-propyl) phosphate was also found. Because these contaminants have long column retention times in GLC, it may not be apparent that these contaminants are present and consequently are likely to have modified the sorbent characteristics of the activated charcoal. Another batch of sorbent tubes bearing the same catalog number and lot number was purchased from the supplier; no flame retardants were found in this batch.

  9. Some Investigations of the Reaction of Activated Charcoal with Fluorine and Uranium Hexafluoride

    SciTech Connect

    Del Cul, G.D.; Fiedor, J.N.; Simmons, D.W.; Toth, L.M.; Trowbridge, L.D.; Williams

    1998-09-01

    The Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory has been shut down since 1969, when the fuel salt was drained from the core into two Hastelloy N drain tanks at the reactor site. Over time, fluorine (F{sub 2}) and uranium hexafluoride (UF{sub 6}) moved from the salt through the gas piping to a charcoal bed, where they reacted with the activated charcoal. Some of the immediate concerns related to the migration of F{sub 2} and UF{sub 6} to the charcoal bed were the possibility of explosive reactions between the charcoal and F{sub 2}, the existence of conditions that could induce a criticality accident, and the removal and recovery of the fissile uranium from the charcoal. This report addresses the reactions and reactivity of species produced by the reaction of fluorine and activated charcoal and between charcoal and F{sub 2}-UF{sub 6} gas mixtures in order to support remediation of the MSRE auxiliary charcoal bed (ACB) and the recovery of the fissile uranium. The chemical identity, stoichiometry, thermochemistry, and potential for explosive decomposition of the primary reaction product, fluorinated charcoal, was determined.

  10. Multiple-dose activated charcoal in acute self-poisoning: a randomised controlled trial

    PubMed Central

    Eddleston, Michael; Juszczak, Edmund; Buckley, Nick A; Senarathna, Lalith; Mohamed, Fahim; Dissanayake, Wasantha; Hittarage, Ariyasena; Azher, Shifa; Jeganathan, K; Jayamanne, Shaluka; Sheriff, MH Rezvi; Warrell, David A

    2008-01-01

    Summary Background The case-fatality for intentional self-poisoning in the rural developing world is 10–50-fold higher than that in industrialised countries, mostly because of the use of highly toxic pesticides and plants. We therefore aimed to assess whether routine treatment with multiple-dose activated charcoal, to interrupt enterovascular or enterohepatic circulations, offers benefit compared with no charcoal in such an environment. Methods We did an open-label, parallel group, randomised, controlled trial of six 50 g doses of activated charcoal at 4-h intervals versus no charcoal versus one 50 g dose of activated charcoal in three Sri Lankan hospitals. 4632 patients were randomised to receive no charcoal (n=1554), one dose of charcoal (n=1545), or six doses of charcoal (n=1533); outcomes were available for 4629 patients. 2338 (51%) individuals had ingested pesticides, whereas 1647 (36%) had ingested yellow oleander (Thevetia peruviana) seeds. Mortality was the primary outcome measure. Analysis was by intention to treat. The trial is registered with controlled-trials.com as ISRCTN02920054. Findings Mortality did not differ between the groups. 97 (6·3%) of 1531 participants in the multiple-dose group died, compared with 105 (6·8%) of 1554 in the no charcoal group (adjusted odds ratio 0·96, 95% CI 0·70–1·33). No differences were noted for patients who took particular poisons, were severely ill on admission, or who presented early. Interpretation We cannot recommend the routine use of multiple-dose activated charcoal in rural Asia Pacific; although further studies of early charcoal administration might be useful, effective affordable treatments are urgently needed. PMID:18280328

  11. Efficacy of activated charcoal and magnesium citrate in the treatment of oral paraquat intoxication.

    PubMed

    Gaudreault, P; Friedman, P A; Lovejoy, F H

    1985-02-01

    The binding capacity of activated charcoal for paraquat was evaluated in vitro and in vivo and compared with Fuller's earth. In vitro activated charcoal absorbs paraquat and is as effective as Fuller's earth. Activated charcoal's absorbing capacity for paraquat is increased when it is suspended in magnesium citrate and is maximal at pH 7.8. Paraquat (200 mg/kg) administered orally to male mice, followed 30 minutes later by activated charcoal, Fuller's earth (4 gm/kg), and magnesium citrate (0.01 cc/gm) resulted in a survival rate of 31% in the controls, 63% in the activated charcoal and Fuller's earth groups, and 69% in the magnesium citrate group (P values not significant). When activated charcoal was administered concomitantly with magnesium citrate, the survival rate was improved significantly to 94% (P less than 0.01). The efficacy and greater availability of activated charcoal and magnesium citrate make these materials the treatment of choice for gastrointestinal decontamination in oral paraquat poisoning. PMID:3970396

  12. Comparison of activated charcoal and ipecac syrup in prevention of drug absorption.

    PubMed

    Neuvonen, P J; Vartiainen, M; Tokola, O

    1983-01-01

    The efficacy of activated charcoal and ipecac syrup in the prevention of drug absorption was studied in 6 healthy adult volunteers, using a randomized, cross-over design. Paracetamol 1000 mg, tetracycline 500 mg and aminophylline 350 mg were ingested on an empty stomach with 100 ml water. Then, after 5 or 30 min, the subjects ingested, either activated charcoal suspension (50 g charcoal), syrup of ipecac, or, only after 5 min, water 300 ml. Activated charcoal, given either after 5 or 30 min, significantly (p less than 0.01 or less 0.05) reduced the absorption of these 3 drugs measured, for example as AUC0-24 h. Syrup of ipecac caused emesis on each occasion, with a mean delay of 15 min. When ipecac was given 5 min after the drugs, its effect on absorption was significant, but when it was given after 30 min only the absorption of tetracycline was reduced. Activated charcoal was significantly (p less than 0.05) more effective than ipecac in reducing drug absorption when given at the same time points. In cases of acute intoxication, depending on the quality and quantity of the drugs ingested, the relative efficacy of charcoal and ipecac may be somewhat different from that observed in the present study. Despite its emetic action, however, ipecac syrup is not very effective in preventing drug absorption and, in general, activated charcoal should also be given after induced emesis or gastric lavage. PMID:6134626

  13. Pharmacokinetics of digoxin cross-reacting substances in patients with acute yellow oleander (Thevetia peruviana) poisoning, including the effect of activated charcoal.

    PubMed Central

    Roberts, Darren M; Southcott, Emma; Potter, Julia M; Roberts, Michael S; Eddleston, Michael; Buckley, Nick A

    2008-01-01

    Intentional self-poisonings with seeds from the yellow oleander tree (Thevetia peruviana) are widely reported. Activated charcoal has been suggested to benefit patients with yellow oleander poisoning by reducing absorption and/or facilitating elimination. Two recent randomised controlled trials (RCTs) assessing the efficacy of activated charcoal reported conflicting outcomes in terms of mortality. The effect of activated charcoal on the pharmacokinetics of Thevetia cardenolides has not been assessed. This information may be useful for determining whether further studies are necessary. Serial blood samples were obtained from patients enrolled in a RCT assessing the relative efficacy of single dose (SDAC) and multiple doses (MDAC) of activated charcoal compared to no activated charcoal (NoAC). The concentration of Thevetia cardenolides was estimated using a digoxin immunoassay. The effect of activated charcoal on cardenolide pharmacokinetics was compared between treatment groups using the AUC24, the 24h Mean Residence Time (MRT24), and regression lines obtained from serial concentration points adjusted for exposure. Erratic and prolonged absorption patterns were noted in each patient group. The apparent terminal half-life was highly variable, with a median time of 42.9h. There was a reduction in MRT24 and the apparent terminal half-life estimated from linear regression in patients administered activated charcoal compared to the control group (NoAC). This effect was approximately equal in patients administered MDAC or SDAC. Activated charcoal appears to favourably influence the pharmacokinetic profile of Thevetia cardenolides in patients with acute self-poisoning, which may have clinical benefits. Given the conflicting clinical outcomes noted in previous RCTs, this mechanistic data supports the need for further studies to determine whether a subgroup of patients (eg. those presenting soon after poisoning) will benefit from activated charcoal. PMID:17164695

  14. Activated charcoal filter counting for radioiodine effluent concentration determination in protein iodinations.

    PubMed

    Button, T M; Hamilton, R G

    1982-12-01

    Regulatory agencies have recently placed emphasis upon quantification of 125I released to the environment during protein iodinations at radioiodination facilities. This necessitates air sampling in order to determine the concentration of 125I in the effluent. Air sample trapping mechanisms generally employed are activated charcoal filters. Difficulty arises in quantifying the activity of 125I trapped because of the attenuation of the 125I decay photons by the charcoal. Evaluation of the activity incident upon commercially available filters using a scintillation detector and large detector source separation is considered here. It is demonstrated that the activity in the filter may be treated as an exponential distribution within an attentuating matrix. This treatment essentially adds a constant correction factor to the counting efficiency of a given geometry for a filter-affluent flow rate combination. Finally, it is shown that an approximation assuming a uniform distribution of activity produces a large error in correction factor to the counting efficiency for the filters examined. PMID:7152949

  15. Activated charcoal-carboxymethylcellulose gel formulation as an antidotal agent for orally ingested aspirin.

    PubMed

    Mathur, L K; Jaffe, J M; Colaizzi, J L; Moriarty, R W

    1976-07-01

    The in vivo effect on aspirin absorption of a potentially more palatable form of activated charcoal was compared to that of a simple aqueous slurry of activated charcoal. The experimental formulation consisted of 20.0 g of activated charcoal, 2.25 g of carboxymethylcellulose (CMC) and 42.8 ml of water; it was tested with and without chocolate syrup as a flavoring agent added just prior to administration. Six subjects were treated in crossover fashion following an aspirin dose of 972 mg. Total urinary excretion of salicylate was measured over 48 hours. Although all three treatments appeared to be effective in reducing the rate and extent of aspirin absorption, the slurry was significantly more effective in reducing the total amount absorbed than the charcoal-CMC gel with chocolate syrup. The slight difference in effectiveness between the gel formulation with and without the chocolate syrup was not significant. PMID:941924

  16. VOST charcoal specification study

    SciTech Connect

    Fuerst, R.G.; Foster, A.L.; Bursey, J.T.

    1996-12-31

    The volatile organic sampling train (VOST) is currently one the leading methodologies available for the sampling and analysis of volatile principal organic hazardous constituents (POHCs) and products of incomplete combustion (PICs) from stationary sources at very low levels. However, revisions to the original method are necessary to maintain VOST as a viable regulatory tool. To provide performance specifications and identify a replacement for SKC Lot 104 charcoal, a VOST charcoal specification study was initiated. The following carbon-based candidate sorbents were considered: Tenax-GR (a graphitized Tenax); a Petroleum-based Charcoal; Ambersorbe XE-340 (hydrophobic carbonized resin bead); Anasorb 747 (beaded active carbon with very regular pore size); Carbosieve{reg_sign} S-III (carbon molecular sieve); and a Beaded Activated Charcoal (BAC) (with a very regular pore size). The results indicated that Tenax-GR showed significantly poorer performance than the other candidates in preliminary experimental results. Ambersorb did not retain the gaseous volatile organic compounds tested as well as the others and recovery of vinyl chloride was very low at all levels of spiking. Carbosieve was eliminated as a candidate replacement because of cost and handling problems. The petroleum-based charcoal was eliminated because of difficulties in handling a finely-divided powder. The availability of Anasorb 747 proved to be the deciding factor between it and the BAC. Performance, cost, ease of handling, and plentiful supply make Anasorb{reg_sign} 747 a good choice for replacement of SKC Lot 104. 1 tab.

  17. Comparative radiocarbon dating of lignite, pottery, and charcoal samples from Babeldaob Island, Republic of Palau

    SciTech Connect

    Anderson, A.; Chappell, J.; Clark, G.; Phear, S.

    2005-07-01

    It is difficult to construct archaeological chronologies for Babeldaob, the main island of Palau (western Micronesia), because the saprolitic clays of the dominant terraced-hill sites and associated ceramic sherds often contain old carbon that originated in lignites. This has implications, as well, for chronologies of sedimentary sequences. Comparative analysis of the dating problem using lignite, pottery, and charcoal samples indicates that, in fact, there are both old and young sources of potential contamination. It is concluded that radiocarbon samples from Babeldaob need to be tested for appropriate carbon content rather than relying solely upon material identification.

  18. Whole-bowel irrigation versus activated charcoal in sorbitol for the ingestion of modified-release pharmaceuticals.

    PubMed

    Kirshenbaum, L A; Mathews, S C; Sitar, D S; Tenenbein, M

    1989-09-01

    Overdose with modified-release pharmaceuticals is an increasing phenomenon. This study examines whole-bowel irrigation as a potential decontamination strategy after overdose with enteric-coated acetylsalicylic acid and compares it with administration of activated charcoal in sorbitol, which is currently the recommended intervention. A three-phase randomized crossover protocol was used in 10 adult volunteers. Each volunteer ingested nine 325 mg doses of enteric-coated acetylsalicylic acid on three occasions, with at least 1 week between each administration period. Serum samples were analyzed for salicylic acid concentration by HPLC. Both interventions decreased peak salicylic acid concentration, time-to-zero salicylic acid concentration, and AUC when compared with control (p less than 0.01). Whole-bowel irrigation was superior to activated charcoal in sorbitol by all three criteria (p less than 0.05). Adverse effects were qualitatively and quantitatively greater during activated charcoal in sorbitol, and the volunteers preferred whole-bowel irrigation over charcoal in sorbitol. Our data suggest that whole-bowel irrigation should be considered for overdose of other modified-release pharmaceuticals. PMID:2673619

  19. Contribution of sorbitol combined with activated charcoal in prevention of salicylate absorption.

    PubMed

    Keller, R E; Schwab, R A; Krenzelok, E P

    1990-06-01

    The use of cathartics and activated charcoal in treating toxic ingestions has become a standard treatment modality. Sorbitol has been shown to be the most rapidly acting cathartic, but its therapeutic significance has been debated. Using a previously described aspirin overdose model, ten healthy volunteers participated in a crossover design study that investigated the effect of activated charcoal alone versus that of activated charcoal and sorbitol in preventing salicylate absorption. In phase 1 of the study, subjects consumed 2.5 g aspirin followed by 25 g activated charcoal one hour later. Urine was collected for 48 hours and analyzed for quantitative salicylate metabolites. Phase 2 was identical except that 1.5 g/kg sorbitol was consumed with the activated charcoal. The mean amount of aspirin absorbed without the use of sorbitol was 1.26 +/- 0.15 g, whereas the mean absorption was 0.912 +/- 0.18 g with the addition of sorbitol. This is a 28% decrease in absorption of salicylates attributable to the use of sorbitol. The difference is significant at P less than .05 by the paired Student's t test. This study demonstrates that the addition of sorbitol significantly decreases drug absorption in a simulated drug overdose model. Effects on absorption in actual overdose situations and on patient outcome should be the subjects of further study. PMID:2188536

  20. A theoretical model for {sup 222}Rn adsorption on activated charcoal canisters in humid air based on Polanyi`s potential theory

    SciTech Connect

    Scarpitta, S.C.

    1995-03-01

    Water vapor interferes with adsorption {sup 222}Rn gas by passive activated charcoal devices used to estimate indoor air concentrations. The {sup 222}Rn adsorption coefficient is the fundamental parameter characterizing charcoal`s ability to adsorb {sup 222}Rn. The Dubinin-Radushkevich equation, based on Polanyi`s potential theory, was modified to include two terms quantifying the effect of both water vapor and sampling time on the {sup 222}Rn adsorption coefficient of passive charcoal devices. A single equation was derived that quantities the {sup 222}Rn adsorption coefficients at any temperature, humidity and exposure time using six experimentally determined physical constants that are unique for a particular passive charcoal device. The theoretical model was verified with published experimental data, and it showed a good correlation between theory and experiment. The model proved to be consistent with experimental data, provided that the amount of water vapor adsorbed by the charcoal device during sampling remains below a critical level, termed the breakpoint. 44 refs., 5 figs., 2 tabs.

  1. Activated charcoal is as effective as fuller's earth or bentonite in paraquat poisoning.

    PubMed

    Okonek, S; Setyadharma, H; Borchert, A; Krienke, E G

    1982-02-15

    In vitro investigations have shown that the adsorption capacity of activated charcoal ('Kohle-Compretten', 'Ultracarbon', E. Merck, Darmstadt, FRG) is just as high as that of 'Fuller's earth' (Surrey powder, Laporte Industries Ltd., Luton, GB) or 'Bentonite BP W.B. (Steetley Minerals Ltd., Milton Keynes, GB). Fuller's earth ('Fullererde') from another manufacturer has had very poor adsorption properties and is thus not suitable for the treatment of paraquat poisoning. Animal experiments have shown that the curative effect of activated charcoal given 0.5, 1, 2, and 3 h after ingestion of 200 and 300 mg paraquat/kg body weight is equally as good or even better than that of 'Fuller's earth' or 'Bentonite BP W.B' Activated charcoal is a substitute of equal value to these mineral soils. PMID:7070010

  2. Molecular and structural properties of polymer composites filled with activated charcoal particles

    NASA Astrophysics Data System (ADS)

    Tahir, Dahlang; Liong, Syarifuddin; Bakri, Fahrul

    2016-03-01

    We have studied the molecular properties, structural properties, and chemical composition of composites by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) spectroscopy, and X-ray fluorescence (XRF) spectroscopy, respectively. FTIR spectra shows absorption band of hydroxyl group (-OH), methyl group (-CH3) and aromatic group (C-C). The absorption band for aromatic group (C-C) shows the formation of carbonaceous in composites. XRF shows chemical composition of composites, which the main chemicals are SO3, Cl, and ZnO. The loss on ignition value (LOI) of activated charcoal indicates high carbonaceous matter. The crystallite size for diffraction pattern from hydrogel polymer is about 17 nm and for activated charcoal are about 19 nm. The crystallite size of the polymer is lower than that of activated charcoal, which make possible of the particle from filler in contact with each other to form continuous conducting polymer through polymer matrix.

  3. Successful treatment of paraquat poisoning: activated charcoal per os and "continuous hemoperfusion".

    PubMed

    Okonek, S; Weilemann, L S; Majdandzic, J; Setyadharma, H; Reinecke, H J; Baldamus, C A; Lohmann, J; Bonzel, K E; Thon, T

    1982-10-01

    Ingestion of paraquat results in an extremely dangerous poisoning. The first aim is to clear the gastrointestinal tract by inducing emesis and performing gastric/gut lavage; as much activated charcoal as possible should be administered per os and as quickly as possible. The best measure to eliminate paraquat from blood and tissue is hemoperfusion with coated activated charcoal; it has to be performed in the sense of "continuous hemoperfusion" about 8 h/d over a period of 2-3 weeks. These measures give a chance to lower the lethality of paraquat poisoning. PMID:7182509

  4. Optimization studies on the features of an activated charcoal-supported urease system.

    PubMed

    Kibarer, G D; Akovali, G

    1996-08-01

    The adsorption of urease onto a well-defined solid support, petroleum-based activated charcoal, has been achieved to provide the enzymatic hydrolysis of urea. In order to produce a biocompatible surface, the enzyme support system has been coated with hexamethyldisiloxane through plasma polymerization. The quality of the resulting coat was tested by electronic spectroscopy for chemical analysis and scanning electron microscopy techniques. Studies on the adsorption of urease, and activity and stability of the enzyme on the support have been in the direction to optimize the features of the charcoal-supported urease and improve its availability for further use in clinical applications. PMID:8853117

  5. Preparation and performance of chitosan encapsulated activated charcoal (ACCB) adsorbents for small molecules.

    PubMed

    Chandy, T; Sharma, C P

    1993-01-01

    A technique is described to encapsulate activated charcoal for haemoperfusion to be used in an artificial liver support. Activated charcoal was encapsulated within chitosan matrix (ACCB) in different concentrations, and was used as the supports for perfusion of a mixture of solutes, having molecular weight ranges from 60 to 69,000; under a flow rate of 8 ml/min. It seems the ACCB may be a good adsorbent system for the removal of toxic uric acid, creatinine, bilirubin, etc., from solutions; while larger molecules such as albumin are adsorbed less. The encapsulated charcoal did not leach out from the matrix during perfusion, and the system may be useful for detoxification of blood. The haemolytic potential of ACCB has been compatible with polystyrene control tubes. However, further studies are needed to determine their behaviour under clinical conditions. PMID:8263676

  6. Effect of supplementing activated charcoal on the intake of honey mesquite leaves by lambs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to determine if intake of honey mesquite (Prosopis glandulosa Torr.) leaves by sheep could be increased by supplementing activated charcoal at 0.0, 0.33, 0.67 or 1.00 g / kg of body weight. Twenty wether lambs (36.6 ± 0.6 kg) were randomly assigned to the 4 treatment levels. La...

  7. Effect of supplementing activated charcoal on the intake of honey mesquite leaves by lambs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to determine if intake of honey mesquite (Prosopis glandulosa Torr.) leaves by sheep could be increased by supplementing four levels of activated charcoal supplemental (0.0, 0.33, 0.67 and 1.00 g/kg of BW). Twenty wether lambs (36.6 ± 0.6 kg) were randomly assigned to the 4 tre...

  8. The Radioactivity Characteristics of the NPP Charcoal Sample Contaminated by Carbon-14 - 13531

    SciTech Connect

    Kim, Hee Reyoung

    2013-07-01

    The radioactivity of {sup 14}C-contaminated charcoal sample was analyzed by using a high temperature oxidation and liquid scintillation counting method. The radioactivity of the sample was monotonically increased according to the increase of the combustion time at each temperature where the experimental uncertainty was calculated in the 95 % confidence level. It showed that the {sup 14}C radioactivity was not completely extracted from the sample by simply increasing the combustion time unless the combustion temperature was high enough. The higher the combustion temperature was, the higher the recovery during the first 30 minutes was. The first 30 minute recoveries were 100 % at a temperature equal to or greater than 450 deg. C. The ratios of the recovery during the first 30 minutes to the total recovery during whole duration were more than 90 % at each experiment temperature. It was understood that the temperature was a critical factor for the complete removal of the {sup 14}C from the waste sample. (authors)

  9. Application of activated charcoal in the downstream processing of bacterial olefinic poly(3-hydroxyalkanoates).

    PubMed

    Wampfler, Bruno; Ramsauer, Thomas; Kehl, Karl; Zinn, Manfred; Thöny-Meyer, Linda

    2010-01-01

    Medium chain length poly(hydroxyalkanoates) (mcl-PHAs) are bacterial thermoplastic elastomers with a large potential in medical applications. The present study provides a novel process to isolate and purify poly([R]-3-hydroxy-omega-undecenoate-co-3-hydroxy-omega-nonenoate-co-3-hydroxy-omega-heptenoate) (PHUE) and poly([R]-3-hydroxy-omega-undecenoate-co-3-hydroxy-omega-nonenoate-co-3-hydroxyoctanoate-co-3-hydroxy-omega-heptenoate-co-3-hydroxyhexanoate) (PHOUE) from Pseudomonas putida species. Three different types of activated charcoal were compared with regard to their capability to selectively remove impurities. The product 'Charcoal activated, powder, pure' from Merck was found to be most suitable. Using ethyl acetate as solvent, the polyesters were extracted from freeze-dried biomass at room temperature and simultaneously purified by addition of activated charcoal at the beginning of the extraction. The period of extraction was one hour and the ratio solvent to biomass was 15:1 (vol/wt). After extraction, the solids were separated by pressure filtration through a metallic lace tissue. The filtrate was again passed through the previously accumulated filter cake, followed by a second filtration through a 0.45 microm membrane to remove finest coal particles. The resulting filtrate was concentrated, thus yielding polyesters whose quality and yield depended on the quantity of activated charcoal applied. For highly pure PHUE and PHOUE with low endotoxin levels, the optimum ratio of activated charcoal to solvent for extraction (V/V) was found to be 0.5 for PHUE and 0.25 for PHOUE. The yields with regard to the raw polymers amounted to 55 wt% for PHUE and 75 wt% for PHOUE, which are acceptable for polymers that can be used for medical applications. PMID:21197841

  10. Microbial Contamination of Ice Machines Is Mediated by Activated Charcoal Filtration Systems in a City Hospital.

    PubMed

    Yorioka, Katsuhiro; Oie, Shigeharu; Hayashi, Koji; Kimoto, Hiroo; Furukawa, Hiroyuki

    2016-06-01

    Although microbial contamination of ice machines has been reported, no previous study has addressed microbial contamination of ice produced by machines equipped with activated charcoal (AC) filters in hospitals. The aim of this study was to provide clinical data for evaluating AC filters to prevent microbial contamination of ice. We compared microbial contamination in ice samples produced by machines with (n = 20) and without an AC filter (n = 40) in Shunan City Shinnanyo Municipal Hospital. All samples from the ice machine equipped with an AC filter contained 10-116 CFUs/g of glucose nonfermenting gram-negative bacteria such as Pseudomonas aeruginosa and Chryseobacterium meningosepticum. No microorganisms were detected in samples from ice machines without AC filters. After the AC filter was removed from the ice machine that tested positive for Gram-negative bacteria, the ice was resampled (n = 20). Analysis found no contaminants. Ice machines equipped with AC filters pose a serious risk factor for ice contamination. New filter-use guidelines and regulations on bacterial detection limits to prevent contamination of ice in healthcare facilities are necessary. PMID:27348980

  11. Effect of electric current frequency on the activation kinetics of raw charcoal

    SciTech Connect

    Shevchenko, A.O.; Ivakhnyuk, G.K.; Fedorov, N.F.

    1993-12-10

    The effect of electric current frequency on the kinetics of raw charcoal activation with water vapor has been investigated. It was established that under the effect of alternating current the rate constant increases under otherwise equal conditions. A dependence of the reaction rate on the current frequency was found. It was discovered that under the effect of alternating current the activation energy of interaction with water vapor diminishes.

  12. Fructo-oligosaccharides purification from a fermentative broth using an activated charcoal column.

    PubMed

    Nobre, C; Teixeira, J A; Rodrigues, L R

    2012-02-15

    In this study, a simple and efficient process to purify fructo-oligosaccharides (FOS) from a fermentative broth was proposed using a single activated charcoal column. The FOS adsorption onto the activated charcoal was modeled by a pseudo-second order model. Several volumes and concentrations of water/ethanol were studied to optimize the selective desorption of sugars from the broth mixture at 25°C. Mixtures containing 50.6% (w/w) of FOS (FOS content in the fermentative broth) were purified to 92.9% (w/w) with a FOS recovery of 74.5% (w/w). Moreover, with the proposed process, fractions with purity up to 97% (w/w) of FOS were obtained. This purification process was also found to be efficient in the desalting of the fermentative broth. PMID:22100432

  13. Intake of honey mesquite (Prosopis glandulosa) leaves by lambs using different levels of activated charcoal

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A 24-day feeding trial was conducted to assess the effect of feeding four levels of activated charcoal (0.0, 0.33, 0.67 and 1.00 g/kg of body weight) on intake of honey mesquite leaves (Prosopis glandulosa Torr.) by 20 wether lambs (36.6 ± 0.6 kg) that were randomly assigned to treatments. Lambs wer...

  14. Activated Charcoal Does Not Reduce Duration of Phenytoin Toxicity in Hospitalized Patients.

    PubMed

    Cumpston, Kirk; Stromberg, Paul; Wills, Brandon K; Rose, S Rutherfoord

    2016-01-01

    Phenytoin toxicity frequently results in a prolonged inpatient admission. Several publications avow multidose activated charcoal (MDAC) will enhance the elimination of phenytoin. However, these claims are not consistent, and the mechanism of enhanced eliminaiton is unproven. The aim of this investigation is to compare the time to reach a clinical composite end point in phenytoin overdose patients treated with no activated charcoal (NoAC), single-dose activated charcoal (SDAC), and MDAC. This was a retrospective study using electronic poison center data. Patients treated in a health care facility with phenytoin concentrations >20 mg/L were included. Patients were grouped by use of SDAC, MDAC, and NoAC. The primary end points were either time to resolution of symptoms, hospital discharge, or the case was closed by a toxicologist. After applying inclusion and exclusion criteria, 132 cases were included for analysis. There were 88 NoAC, 13 SDAC, and 31 MDAC cases. The groups were similar in symptomatology, age, and chronicity of expsoure. Mean peak phenytoin concentrations (SD) were 42 mg/L (12), 41 mg/L (11), and 42 mg/L (11) for NoAC, SDAC, and MDAC, respectively. Mean time to reach the study end point was 39 hours [95% confidence interval (CI), 31-48], 52 hours (95% CI, 36-68), and 60 hours (95% CI, 45-75) for NoAC, SDAC, and MDAC, respectively. The groups appeared similar with respect to peak phenytoin concentrations and prevalence of signs and symptoms. In this observational series, the use of activated charcoal was associated with increased time to reach the composite end point of clinical improvement. PMID:24621645

  15. Adsorption of H2, Ne, and N2 on Activated Charcoal

    NASA Technical Reports Server (NTRS)

    Chang, C. K.; Tward, E.; Boudaie, K. I.

    1986-01-01

    9-page report presents measured adsorption isotherms of hydrogen, neon, and nitrogen on activated charcoal for temperatures from 77 to 400 K and pressures from 1 to 80 atmospheres (0.1 to 8.1 MPa). Heats of adsorption calculated from isotherms also presented. Report gives expressions, based on ideal-gas law, which show relationship between different definitions of volume of gas adsorbed and used in describing low-pressure isotherms.

  16. Adsorptive desulphurization study of liquid fuels using Tin (Sn) impregnated activated charcoal.

    PubMed

    Shah, Syed Sikandar; Ahmad, Imtiaz; Ahmad, Waqas

    2016-03-01

    Keeping in view the growing concern regarding desulphurization of petroleum products, the present study was under taken to investigate the efficiency of tin impregnated activated charcoal (Sn-AC) as a potential adsorbent for the desulphurization of model and real commercial straight run kerosene and diesel oil samples. The adsorbent Sn-AC was prepared by wet impregnation process in the laboratory and characterized by SEM, EDX and surface area analysis. Initial experiments were carried out using model oil, which was prepared by dissolving dibenzothiophene (DBT) in cyclohexane, the optimum conditions for desulfurization were found to be, 60°C temperature, 1h contact time and adsorbent dosage of 0.8g, under which about 99.4% of DBT removal was attained. Under optimized conditions the desulfurization of real oil i.e., kerosene and diesel oil was also investigated. Kinetic studies revealed that DBT adsorption followed pseudo second order kinetics and the data best fits in the Langmuir adsorption isotherm as compared to Freundlich adsorption isotherm model. The adsorbent could be easily regenerated simply by washing with toluene for a multiple cycles and reused without losing its efficiency. PMID:26551224

  17. Spacelab Charcoal Analyses

    NASA Technical Reports Server (NTRS)

    Slivon, L. E.; Hernon-Kenny, L. A.; Katona, V. R.; Dejarme, L. E.

    1995-01-01

    This report describes analytical methods and results obtained from chemical analysis of 31 charcoal samples in five sets. Each set was obtained from a single scrubber used to filter ambient air on board a Spacelab mission. Analysis of the charcoal samples was conducted by thermal desorption followed by gas chromatography/mass spectrometry (GC/MS). All samples were analyzed using identical methods. The method used for these analyses was able to detect compounds independent of their polarity or volatility. In addition to the charcoal samples, analyses of three Environmental Control and Life Support System (ECLSS) water samples were conducted specifically for trimethylamine.

  18. Aminocyclopyrachlor sorption in biochar and activated charcoal amended soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aminocyclopyrachlor is a new herbicide active ingredient, classified as a member of the new chemical class “pyrimidine carboxylic acids”. It is used for control of broadleaf weeds and brush on non-cropland. Due to its potential mobility in some soils, there is interest in whether aminocyclopyrachlor...

  19. Binding Potency of Heparin Immobilized on Activated Charcoal for DNA Antibodies.

    PubMed

    Snezhkova, E A; Tridon, A; Evrard, B; Nikolaev, V G; Uvarov, V Yu; Tsimbalyuk, R S; Ivanuk, A A; Komov, V V; Sakhno, L A

    2016-02-01

    In vitro experiments showed that heparin adsorbed on activated charcoal can bind antibodies raised against native and single-stranded DNA in a diluted sera pool with a high level of these DNA. Thus, heparin used as anticoagulant during hemosorption procedure can demonstrate supplementary therapeutic activity resulting from its interaction with various agents involved in acute and chronic inflammatory reactions such as DNA- and RNA-binding substances, proinflammatory cytokines, complement components, growth factors, etc. Research and development of heparin-containing carbonic adsorbents for the therapy of numerous inflammatory and autoimmune diseases seems to be a promising avenue in hematology. PMID:26902353

  20. Use of Activated Charcoal for {sup 220}Rn Adsorption for Operations Associated with the Uranium Deposit in the Auxiliary Charcoal Bed at the Molten Salt Reactor Experiment Facility

    SciTech Connect

    Coleman, R.L.

    1999-03-01

    Measurements have been collected with the purpose of evaluating the effectiveness of activated charcoal for the removal of {sup 220}Rn from process off-gas at the Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory. A series of bench-scale tests were performed at superficial flow velocities of 10, 18, 24, and 33 cm/s (20, 35, 47, and 65 ft/min) with a continuous input concentration of {sup 220}Rn in the range of 9 x 10{sup 3} pCi/L. In addition, two tests were performed at the MSRE facility by flowing helium through the auxiliary charcoal bed uranium deposit. These tests were performed so that the adsorptive effectiveness could be evaluated with a relatively high concentration of {sup 220}Rn. In addition to measuring the effectiveness of activated charcoal as a {sup 220}Rn adsorption media, the source term for available {sup 220}Rn in the deposit is actually available for removal and that the relative activity of fission gases is very small when compared to {sup 220}Rn. The measurement data were then used to evaluate the expected effectiveness of a proposed charcoal adsorption bed consisting of a right circular cylinder having a diameter of 43 cm and a length of 91 cm (17 in. I.D. x 3 ft.). The majority of the measurement data predicts an overall 220Rn activity reduction factor of about 1 x 10{sup 9} for such a design; however, two measurements collected at a flow velocity of 18 cm/s (35 ft/min) indicated that the reduction factor could be as low as 1 x 10{sup 6}. The adsorptive capacity of the proposed trap was also evaluated to determine the expected life prior to degradation of performance. Taking a conservative vantage point during analysis, it was estimated that the adsorption effectiveness should not begin to deteriorate until a {sup 220}Rn activity on the order of 10{sup 10} Ci has been processed. It was therefore concluded that degradation of performance would likely occur as the result of causes other than filling by radon progeny.

  1. Use of Activated Charcoal for Rn-220 Adsorption for Operations Associated with the Uranium Deposit in the Auxiliary Charcoal Bed at the Molten Salt Reactor Experiment Facility

    SciTech Connect

    Coleman, R.L.

    1999-03-17

    Measurements have been collected with the purpose of evaluating the effectiveness of activated charcoal for the removal of {sup 220}Rn from process off-gas at the Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory. A series of bench-scale tests were performed at superficial flow velocities of 10, 18, 24, and 33 cm s{sup -1} (20, 35, 47, and 65 ft min{sup -1}) with a continuous input concentration of {sup 220}Rn in the range of 9 x 10{sup 3} pCi L{sup -1}. In addition, two tests were performed at the MSRE facility by flowing helium through the auxiliary charcoal bed uranium deposit. These tests were performed so that the adsorptive effectiveness could be evaluated with a relatively high concentration of {sup 220}Rn. In addition to measuring the effectiveness of activated charcoal as a {sup 220}Rn adsorption media, the source term for available {sup 220}Rn and gaseous fission products was evaluated and compared to what is believed to be present in the deposit. The results indicate that only a few percent of the total {sup 220}Rn in the deposit is actually available for removal and that the relative activity of fission gases is very small when compared to {sup 220}Rn. The measurement data were then used to evaluate the expected effectiveness of a proposed charcoal adsorption bed consisting of a right circular cylinder having a diameter of 43 cm and a length of 91 cm (17 in. I.D. x 3 ft.). The majority of the measurement data predicts an overall {sup 220}Rn activity reduction factor of about 1 x 10{sup 9} for such a design; however, two measurements collected at a flow velocity of 18 cm s{sup -1} (35 ft min{sup -1}) indicated that the reduction factor could be as low as 1 x 10{sup 6}. The adsorptive capacity of the proposed trap was also evaluated to determine the expected life prior to degradation of performance. Taking a conservative vantage point during analysis, it was estimated that the adsorption effectiveness should not begin to deteriorate

  2. Serum acetaminophen assay using activated charcoal adsorption and gas chromatography without derivatization.

    PubMed

    Jeevanandam, M; Novic, B; Savich, R; Wagman, E

    1980-01-01

    A quantitative assay of acetaminophen in serum has been developed. The drug, together with an internal standard 2-acetamidophenol, is adsorbed on activated charcoal and then extracted into a mixture of ethyl acetate and isopropanol. This extract is then analyzed, without any derivatization, by gas chromatography. The isothermal analysis yielded a good, highly reproducible separation. The drug peak was symmetrical and without any tailing. The peak height response ratio was found to be linear with concentrations ranging from 25-500 ng/L. No interference was observed with the various drugs or metabolites which are commonly encountered in human serum. PMID:7421146

  3. Evaluation of radon adsorption characteristics of a coconut shell-based activated charcoal system for radon and thoron removal applications.

    PubMed

    Karunakara, N; Sudeep Kumara, K; Yashodhara, I; Sahoo, B K; Gaware, J J; Sapra, B K; Mayya, Y S

    2015-04-01

    Radon ((222)Rn), thoron ((220)Rn), and their decay products contribute a major fraction (more than 50%) of doses received from ionisation radiation in public domain indoor environments and occupation environments such as uranium mines, thorium plants, and underground facilities, and are recognised as important radiological hazardous materials, which need to be controlled. This paper presents studies on the removal of (222)Rn and (220)Rn from air using coconut shell-based granular activated charcoal cylindrical adsorber beds. Experiments were conducted to evaluate the (222)Rn and (220)Rn adsorption characteristics, and the mitigation efficiency of coconut-based activated charcoal available in India. The performance parameters evaluated include breakthrough time (τ) and adsorption coefficient (K), and degassing characteristics of the charcoal bed of varying dimensions at different flow rates. While the breakthrough for (222)Rn occurred depending on the dimension of the adsorber bed and flow rates, for (220)Rn, the breakthrough did not occur. The breakthrough curve exhibited a stretched S-shape response, instead of the theoretically predicted sharp step function. The experiments confirm that the breakthrough time individually satisfies the quadratic relationship with respect to the diameter of the bed, and the linear relationship with respect to the length, as predicted in the theory. The K value varied in the range of 2.3-4.12 m(3) kg(-1) with a mean value of 2.99 m(3) kg(-1). The K value was found to increase with the increase in flow rate. Heating the charcoal to ∼ 100 °C resulted in degassing of the adsorbed (222)Rn, and the K of the degassed charcoal and virgin charcoal were found to be similar with no deterioration in performance indicating the re-usability of the charcoal. PMID:25658471

  4. VOST charcoal specification study

    SciTech Connect

    Foster, A.L.; Bursey, J.T.

    1995-07-01

    The volatile organic sampling train, SW-846 Method 0030, (VOST) is currently one of the leading methodology`s available for the sampling and analysis of volatile organic hazardous compounds from stationary sources at very low levels. The method does not identify a specific equivalent sorbent, nor the performance specifications which would allow determination of an equivalent. Lot 104 petroleum-based charcoal is no longer commercially available. Laboratories are presently using a wide range of substitutes with varying performance from batch to batch of charcoal. To provide performance specifications and identify a replacement for SKC Lot 104 charcoal, a VOST charcoal specification study was initiated. Performance, cost, ease of handling, and plentiful supply make Anasorb 747 a good choice for replacement of SKX Lot 104.

  5. Fusion reactor high vacuum pumping: Charcoal cryosorber tritium exposure results

    SciTech Connect

    Sedgley, D.W.; Walthers, C.R.; Jenkins, E.M. )

    1991-01-01

    Recent experiments, have shown the practically of using activated charcoal (coconut charcoal) at 4{degrees}K to pump helium and hydrogen isotopes for a fusion reactor. Both speed and capacity for deuterium/helium and tritium/helium-3 mixtures were shown to be satisfactory. The long term effects of tritium on the charcoal/cement system developed by Grumman and LLNL were not known and a program was undertaken to see what, if any, effect long term tritium exposure has on the cryosorber. Several charcoal on aluminum test samples were subjected to six months exposure of tritium at approximately 77{degrees}K. The tritium was scanned several times with a residual gas analyzer and the speed-capacity performance of the samples was measured before, approximately half way through and after the exposure. Modest effects were noted which would not seriously restrict charcoal's use as a cryosorber for fusion reactor high vacuum pumping applications. 4 refs., 8 figs.

  6. Synthesis of a high-yield activated carbon by air gasification of macadamia nut shell charcoal

    SciTech Connect

    Dai, X.; Antal, M.J. Jr.

    1999-09-01

    Macadamia nut shell charcoal was heated in an inert environment to temperatures above 1000 K (carbonized), reacted with oxygen (Po{sub 2} = 2.68--11.3 kPa) at temperatures between 525 and 586 K (oxygenated), and heated again in an inert environment to temperatures above 1000 K (activated) to produce an activated carbon. Carbons produced by this process possess surface areas and iodine numbers in the range of 400--550. Overall yields of these carbons (based on the dry, raw macadamia nut shell feed) ranged from 24 to 30 wt %. Under the conditions employed in this work, the rates of chemisorption and gasification were not mass transfer limited. Initially, the gasification reaction was first-order with respect to oxygen concentration but became independent of oxygen concentration as the surface sites of the carbon became saturated with oxygen.

  7. Charcoal burner

    SciTech Connect

    Bakic, M.C.

    1988-12-27

    A combustible fuel apparatus is described comprising: side walls formed contiguous with and extending upward from a base and converging to form a closed container, having stacked charcoal fuel particles therein. The base may be placed directly on a substantially horizontal surface and the container may be ignited and substantially burned to ash, and the charcoal fuel particles may be ignited and sufficiently burned for cooking, wherein the charcoal fuel particles are stacked on the base in a relatively stable position prior to the igniting of the container, and are maintained in a relatively stable position during and after the igniting and burning of the container, whereby a mound of ignited charcoal fuel particles remains on the substantially horizontal surface after the burning of the container, the mound having a configuration substantially similar to the shape of the container prior to the combustion thereof.

  8. Radon Adsorbed in Activated Charcoal--A Simple and Safe Radiation Source for Teaching Practical Radioactivity in Schools and Colleges

    ERIC Educational Resources Information Center

    Al-Azmi, Darwish; Mustapha, Amidu O.; Karunakara, N.

    2012-01-01

    Simple procedures for teaching practical radioactivity are presented in a way that attracts students' attention and does not make them apprehensive about their safety. The radiation source is derived from the natural environment. It is based on the radioactivity of radon, a ubiquitous inert gas, and the adsorptive property of activated charcoal.…

  9. Fabrication of Activated Rice Husk Charcoal by Slip Casting as a Hybrid Material for Water Filter Aid

    NASA Astrophysics Data System (ADS)

    Tuaprakone, T.; Wongphaet, N.; Wasanapiarnpong, T.

    2011-04-01

    Activated charcoal has been widely used as an odor absorbent in household and water purification industry. Filtration equipment for drinking water generally consists of four parts, which are microporous membrane (porous alumina ceramic or diatomite, or porous polymer), odor absorbent (activated carbon), hard water treatment (ion exchange resin), and UV irradiation. Ceramic filter aid is usually prepared by slip casting of alumina or diatomite. The membrane offers high flux, high porosity and maximum pore size does not exceed 0.3 μm. This study investigated the fabrication of hybrid activated charcoal tube for water filtration and odor absorption by slip casting. The suitable rice husk charcoal and water ratio was 48 to 52 wt% by weight with 1.5wt% (by dry basis) of CMC binder. The green rice husk charcoal bodies were dried and fired between 700-900 °C in reduction atmosphere. The resulting prepared slip in high speed porcelain pot for 60 min and sintered at 700 °C for 1 h showed the highest specific surface area as 174.95 m2/g. The characterizations of microstructure and pore size distribution as a function of particle size were investigated.

  10. An EELS-based study of the effects of pyrolysis on natural carbonaceous materials used for activated charcoal preparation.

    PubMed

    Jeanne-Rose, V; Golabkan, V; Mansot, J L; Largitte, L; Césaire, T; Ouensanga, A

    2003-04-01

    Electron energy-loss spectroscopy (EELS) has been used to characterize the electronic structure of charcoal phases at the nanoscale, thus demonstrating that the technique can be applied to environmental science. Activated charcoal is extensively used to remove pollutants from liquid and gaseous sewage. It is mainly obtained by activation of coke or charcoal produced from ligneous precursors. The present study concerns the use of by-products of local Caribbean agriculture, such as sugar cane bagasse, fruit stones and seeds, for use as activated charcoal precursors. Charcoal phases are prepared by high-temperature pyrolysis of lignocellulosic raw materials under a nitrogen gas flow. With the aim of optimizing the pyrolysis temperature and duration and oxygen content, the concentration of carbon sp2 hybridized chemical bonds and structural ordering have been followed by EELS for different treatment temperatures. To quantify the carbon sp2 content, near edge structure (NES) at the carbon K edge has been measured to determine the strength of pi --> pi* and 1s --> pi* transitions. Three precursors of plant origin, shells of Terminalia catappa and Acrocomia karukerana and seeds of Psidium guajava, with the pyrolysis temperatures between 600 and 900 degrees C, were investigated. The fraction of carbon sp2 bonding is found to increase when the temperature rises from 600 degrees C to the range 700-750 degrees C and becomes stable at higher temperatures. For temperatures in excess of 700 degrees C, structural ordering probably occurs and well-defined 1s --> sigma* NES is present, whose intensity increases with increasing preparation temperature. For the highest temperature of around 900 degrees C, the structure of the final product is less well organized than graphitized carbon but a few per cent of a highly ordered phase is found. PMID:12694416

  11. Charcoal rot

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Charcoal rot is reported occasionally on alfalfa in the U.S. and has also been found in Australia, Pakistan, Uganda, east Africa, and the former Soviet Union. The fungus causing the disease is widespread throughout tropical and subtropical countries. It causes disease on more than 500 crop and we...

  12. Adsorption of ammonium dinitramide (ADN) from aqueous solutions. 1. Adsorption on powdered activated charcoal.

    PubMed

    Santhosh, G; Venkatachalam, S; Ninan, K N; Sadhana, R; Alwan, S; Abarna, V; Joseph, M A

    2003-03-17

    Investigations on the adsorption of ammonium dinitramide (NH(4)N(NO(2))(2)) (ADN) from aqueous solutions on powdered activated charcoal (PAC) were carried out in order to find out an effective and easier method of separating ADN from aqueous solutions. The effectiveness of PAC in the selective adsorption of ADN from aqueous solutions of ADN (ADN-F) and ADN in presence of sulfate (SO(4)(2-)) and nitrate (NO(3)(-)) ions (ADN-PS) was examined and compared using batch and column methods. The adsorption process follows both Langmuir and Freundlich adsorption isotherms and the isotherm parameters for the models were determined. The observed data favor the formation of monolayer adsorption. The adsorption capacities were found to be 63.3, 119, 105.3 and 82 mg of ADN per g of PAC for ADN-F (batch), ADN-PS (batch), ADN-F (column) and ADN-PS (column), respectively. Break-through curves for ADN-F and ADN-PS were obtained for the optimization of separation of ADN from aqueous solutions. Elution curves were generated for the desorption of ADN from PAC using hot water as eluent. PMID:12628781

  13. Enhanced elimination of piroxicam by administration of activated charcoal or cholestyramine.

    PubMed

    Ferry, D G; Gazeley, L R; Busby, W J; Beasley, D M; Edwards, I R; Campbell, A J

    1990-01-01

    This study has compared the effect of repeated administration of charcoal and cholestyramine on the elimination of piroxicam. Eight young adults were given piroxicam as a single dose of 20 mg, on 3 separate occasions. On one of the occasions charcoal was also given. On another occasion cholestyramine was also administered. The mean elimination half-life after piroxicam alone was 53.1 h. This was reduced to 40.0 h by charcoal administration and to 29.6 h after administration of cholestyramine. In the second phase of the study 7 elderly subjects received piroxicam 20 mg for 14 days on two occasions. Cholestyramine administration at the end of one of the periods reduced the mean elimination half-life of piroxicam from 52.3 h to 27.3 h. PMID:2095346

  14. Gas chromatographic determination of microamounts of glycols and their esters in aqueous medium using adsorption on activated charcoal

    SciTech Connect

    Begunov, G.A.; Titovskaya, V.N.; Galenko, A.V.

    1987-11-10

    Rapid growth of production of glycols and their derivatives, especially methyl and ethyl esters, and wide use of these substances in various branches of the national economy (1) inevitably necessitate analytical monitoring of their content in waste waters and various water bodies. The authors studied the scope of gas-chromatographic determination of microamounts of glycols and their esters in aqueous media at the sanitary standards level (10/sup -5/%) using activated charcoal for their adsorption concentration from aqueous solutions, desorption from the charcoal by ethanol, and evaporationconcentration of the alcoholic solutions. The quantitative concentration characteristics were studied with reference to ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethyleneglycol, tripropylene glycol, tetraethylene glycol, ethylcellosolve, ethyl carbitol, and monoethyl ester of triethylene glycol.

  15. Population pharmacokinetics and pharmacodynamics of escitalopram in overdose and the effect of activated charcoal

    PubMed Central

    van Gorp, Freek; Duffull, Stephen; Hackett, L Peter; Isbister, Geoffrey K

    2012-01-01

    AIMS To describe the pharmacokinetics and pharmacodynamics (PKPD) of escitalopram in overdose and its effect on QT prolongation, including the effectiveness of single dose activated charcoal (SDAC). METHODS The data set included 78 escitalopram overdose events (median dose, 140 mg [10–560 mg]). SDAC was administered 1.0 to 2.6 h after 12 overdoses (15%). A fully Bayesian analysis was undertaken in WinBUGS 1.4.3, first for a population pharmacokinetic (PK) analysis followed by a PKPD analysis. The developed PKPD model was used to predict the probability of having an abnormal QT as a surrogate for torsade de pointes. RESULTS A one compartment model with first order input and first-order elimination described the PK data, including uncertainty in dose and a baseline concentration for patients taking escitalopram therapeutically. SDAC reduced the fraction absorbed by 31% and reduced the individual predicted area under the curve adjusted for dose (AUCi/dose). The absolute QT interval was related to the observed heart rate with an estimated individual heart rate correction factor (α = 0.35). The heart rate corrected QT interval (QTc) was linearly dependent on predicted escitalopram concentration [slope = 87 ms/(mg l–1)], using a hypothetical effect-compartment (half-life of effect-delay, 1.0h). Administration of SDAC significantly reduced QT prolongation and was shown to reduce the risk of having an abnormal QT by approximately 35% for escitalopram doses above 200 mg. CONCLUSIONS There was a dose-related lengthening of the QT interval that lagged the increase in drug concentration. SDAC resulted in a moderate reduction in fraction of escitalopram absorbed and reduced the risk of the QT interval being abnormal. PMID:21883384

  16. The pharmacokinetics of sertraline in overdose and the effect of activated charcoal

    PubMed Central

    Cooper, Joyce M; Duffull, Stephen B; Saiao, Ana S; Isbister, Geoffrey K

    2015-01-01

    Aims To investigate the pharmacokinetics (PK) of sertraline in overdose and the effect of single dose activated charcoal (SDAC). Methods Patients presenting to a toxicology unit with sertraline overdoses had demographic and clinical information recorded, and serial serum collected for measurement of sertraline concentrations. Monolix® version 4.2 was used to develop a population PK model of sertraline overdose and the effect of SDAC. Uncertainty in dose time was accounted for by shifting dose time using lag time with between subject variability (BSV). BSV on relative fraction absorbed was used to model uncertainty in dose. Results There were 77 timed sertraline concentrations measured in 28 patients with sertraline overdoses with a median dose of 1550 mg (250–5000 mg). SDAC was given to seven patients between 1.5 and 4 h post-overdose. A one compartment model with lag time of 1 h and first order input and elimination adequately described the data. Including BSV on both lag time and relative fraction absorbed improved the model. The population PK parameter estimates for absorption rate constant, volume of distribution and clearance were 0.895 h−1, 5340 l and 130 l h−1, respectively. The calculated half-life of sertraline following overdose was 28 h (IQR 19.4−30.6h). When given up to 4 h post-overdose, SDAC significantly increased the clearance of sertraline by a factor of 1.9, decreased the area under the curve and decreased the maximum plasma concentration (Cmax). Conclusions Sertraline had linear kinetics in overdose with parameter values similar to those in therapeutic use. SDAC is effective in increasing clearance when given 1.5 to 4 h post-overdose. PMID:25155462

  17. Study of Single Catalytic Events at Copper-in-Charcoal: Localization of Click Activity Through Subdiffraction Observation of Single Catalytic Events.

    PubMed

    Decan, Matthew R; Scaiano, Juan C

    2015-10-15

    Single molecule fluorescence microscopy reveals that copper-in-charcoal--a high performance click catalyst- has remarkably few catalytic sites, with 90% of the charcoal particles being inactive, and for the catalytic ones the active sites represent a minute fraction (∼0.003%) of the surface. The intermittent nature of the catalytic events enables subdiffraction resolution and mapping of the catalytic sites. PMID:26722775

  18. Occupational exposure to complex mixtures of volatile organic compounds in ambient air: desorption from activated charcoal using accelerated solvent extraction can replace carbon disulfide?

    PubMed

    Fabrizi, Giovanni; Fioretti, Marzia; Rocca, Lucia Mainero

    2013-01-01

    A desorption study of 57 volatile organic compounds (VOCs) has been conducted by use of accelerated solvent extraction (ASE) and gas chromatography-mass spectrometry. Different solvents were tested to extract activated charcoal tubes with the objective of replacing carbon disulfide, used in official methods, because of its highly toxic health and environmental effects. Extraction conditions, for example temperature and number of cycles, were investigated and optimized. The definitive extraction procedure selected was use of acetone at 150 °C and two consecutive extraction cycles at a pressure of 1,500 psi. Considering a sample volume of 0.005 Nm(3), corresponding to a sampling time of 8 h at a flow rate of 0.01 L min(-1), the method was validated over the concentration range 65-26,300 μg Nm(-3). The lowest limit of quantification was 6 μg Nm(-3), and recovery for the 93 % of analytes ranged from 65 to 102 %. For most of the compounds, relative standard deviations were less than 15 % for inter and intra-day precision. Uncertainty of measurement was also determined: the relative expanded uncertainty was always below 29.6 %, except for dichlorodifluoromethane. This work shows that use of friendlier solvent, for example acetone, coupled with use of ASE, can replace use of CS(2) for chemical removal of VOCs from activated charcoal. ASE has several advantages over traditional solvent-extraction methods, including shorter extraction time, minimum sample manipulation, high reproducibility, and less extraction discrimination. No loss of sensitivity occurs and there is also a salutary effect on bench workers' health and on the smell of laboratory air. PMID:22968683

  19. Carcinogenic PAH in waterpipe charcoal products

    PubMed Central

    Sepetdjian, Elizabeth; Saliba, Najat; Shihadeh, Alan

    2010-01-01

    Because narghile waterpipe (shisha, hooka) smoking normally involves the use of burning charcoal, smoke inhaled by the user contains constituents originating from the charcoal in addition to those from the tobacco. We have previously found that charcoal accounts for most of the polyaromatic hydrocarbons (PAH) and carbon monoxide in the smoke of the waterpipe, both of which are present in alarming quantities. Because charcoal manufacturing conditions favor formation of PAH, it is reasonable to assume that charcoal sold off the shelf may be contaminated by PAH residues. These residues may constitute a significant fraction of the PAH inhaled by the waterpipe user and those in her/his vicinity. We measured PAH residues on three kinds of raw waterpipe charcoal sampled from Beirut stores and cafés. We found that PAH residues in raw charcoal can account for more than half of the total PAH emitted in the mainstream and sidestream smoke, and about one sixth of the carcinogenic 5- and 6-ring PAH compounds. Total PAH content of the three charcoal types varied systematically by a factor of six from the charcoal with the least to the greatest PAH residue. These findings indicate the possibility of regulating charcoal carcinogen content. PMID:20807559

  20. Carcinogenic PAH in waterpipe charcoal products.

    PubMed

    Sepetdjian, Elizabeth; Saliba, Najat; Shihadeh, Alan

    2010-11-01

    Because narghile waterpipe (shisha, hooka) smoking normally involves the use of burning charcoal, smoke inhaled by the user contains constituents originating from the charcoal in addition to those from the tobacco. We have previously found that charcoal accounts for most of the polyaromatic hydrocarbons (PAH) and carbon monoxide in the smoke of the waterpipe, both of which are present in alarming quantities. Because charcoal manufacturing conditions favor formation of PAH, it is reasonable to assume that charcoal sold off the shelf may be contaminated by PAH residues. These residues may constitute a significant fraction of the PAH inhaled by the waterpipe user and those in her/his vicinity. We measured PAH residues on three kinds of raw waterpipe charcoal sampled from Beirut stores and cafés. We found that PAH residues in raw charcoal can account for more than half of the total PAH emitted in the mainstream and sidestream smoke, and about one sixth of the carcinogenic 5- and 6-ring PAH compounds. Total PAH content of the three charcoal types varied systematically by a factor of six from the charcoal with the least to the greatest PAH residue. These findings indicate the possibility of regulating charcoal carcinogen content. PMID:20807559

  1. Reduction in uptake by rice and soybean of aromatic arsenicals from diphenylarsinic acid contaminated soil amended with activated charcoal.

    PubMed

    Arao, Tomohito; Maejima, Yuji; Baba, Koji

    2011-10-01

    Activated charcoal (AC) amendment has been suggested as a promising method to immobilize organic contaminants in soil. We performed pot experiments with rice and soybean grown in agricultural soil polluted by aromatic arsenicals (AAs). The most abundant AA in rice grains and soybean seeds was methylphenylarsinic acid (MPAA). MPAA concentration in rice grains was significantly reduced to 2% and 3% in 0.2% AC treated soil compared to untreated soil in the first year of rice cultivation. In the second year, MPAA concentration in rice grains was significantly reduced to 15% in 0.2% AC treated soil compared to untreated soil. MPAA concentration in soybean seeds was significantly reduced to 44% in 0.2% AC treated soil compared to untreated soil. AC amendment was effective in reducing AAs in rice and soybean. PMID:21782301

  2. Effect of a catalyst on the kinetics of reduction of celestite (SrSO{sub 4}) by active charcoal

    SciTech Connect

    Sonawane, R.S.; Kale, B.B.; Apte, S.K.; Dongare, M.K.

    2000-02-01

    Reduction of celestite (SrSO{sub 4}) powder with particles of active charcoal has been studied extensively in the absence and presence of catalysts. The optimum temperature at the charging zone has been optimized to get a maximum water-soluble strontium sulfide value. The strontium value has been analyzed using a chemical method, which was verified by the instrumental method using an inductively coupled plasma-optical emission spectrophotometer (ICP-OES). The conversion-time data have been analyzed by using a modified volume-reaction (MVR) model, and the effect of the catalyst on kinetic parameters has been elucidated. It was found that potassium carbonate, potassium dichromate, sodium carbonate, and sodium dichromate catalysts were found to enhance the reaction rate quite satisfactorily in the reduction of the celestite (SrSO{sub 4}).

  3. Somatic proembryo production from excised, wounded zygotic carrot embryos on hormone-free medium: evaluation of the effects of pH, ethylene and activated charcoal

    NASA Technical Reports Server (NTRS)

    Smith, D. L.; Krikorian, A. D.

    1990-01-01

    Wounded zygotic embryos of cultivated carrot produce somatic proembryos on hormone-free nutrient medium containing 1 mM NH4+ as the sole nitrogen source. Continued maintenance of proembryos on this medium leads to a "pure" culture of preglobular stage proembryos (PGSPs). Ethylene had no effect on this process. Also, somatic embryo production was not affected by growing cultures on activated charcoal-impregnated filter papers. However, somatic proembyros initiated on activated charcoal papers were not maintainable as PGSPs and developed into later embryo stages. Normally, medium pH dropped from 5.7 to 4 during each subculture period, but when using activated charcoal papers the pH endpoint was around 6 - 7 due to a leachable substance(s) within the filter papers. When powdered, activated charcoal was used in the medium as an adsorbent of products potentially released after wounding, pH dropped at the normal rate and to the expected levels; proembryos did not mature into later embryo stages and were maintainable exclusively as PGSPs. Low pH (approximately 4) is detrimental to proembyro production, but is essential to maintaining PGSPs on hormone-free nutrient medium, whereas a sustained pH > or = 5.7 allows continued development of PGSPs into later embryo stages.

  4. Simultaneous removal of 2,4-dichlorophenol and Cd from soils by electrokinetic remediation combined with activated bamboo charcoal.

    PubMed

    Ma, Jian Wei; Wang, Fa Yuan; Huang, Zheng Hong; Wang, Hui

    2010-04-15

    An in situ electrokinetic remediation technique was designed by combining the uniform electrokinetic technology with a new-type of bamboo charcoal as adsorbent. A bench-scale experiment was conducted to investigate the application of this technique for simultaneous removal of 2,4-dichlorophenol (2,4-DCP) and Cd from a sandy loam at different periodic polarity-reversals. The contaminated soil was artificially spiked with 100 mg/kg 2,4-DCP and 500 mg/kg Cd. Two modes of polarity-reversal intervals of 12 and 24 h were included. After 10.5 d of operation, about 75.97% of Cd and 54.92% of 2,4-DCP were removed from soil at intervals of 24 h, whilst only 40.13% of Cd and 24.98% of 2,4-DCP were removed at intervals of 12 h. Soil water contents under two operation modes both significantly decreased, but evenly distributed spatially. Soil pH values under two operation modes were all maintained in the range from 7.2 to 7.4, close to the initial value. The electricity consumption per day was 12.24 and 11.61 kWh/m(3)/d, respectively at polarity-reversal intervals of 12 and 24 h. In conclusion, at polarity-reversal interval of 24 h, electroremediation combined with activated bamboo charcoal was effective in simultaneous removal of 2,4-DCP and Cd from soil. Our results indicate a promising potential in in situ electroremediation of soils co-contaminated with organics and heavy metals. PMID:20006426

  5. Handbook of charcoal making: the traditional and industrial methods

    SciTech Connect

    Emrich, W.

    1985-01-01

    The reviewer credits this handbook with expanding knowledge about the economic value of charcoal, particularly in the European area. The 10 chapters are: (1) history and fundamentals of the charcoal process, (2) traditional methods of the smallholder producer, (3) concepts and technology for the industrial producer, (4) recovering commercial products from pyrolysis oil, (5) raw materials supply, (6) end-use markets for by-products, (7) planning a charcoal venture, (8) charcoal briquettes and activated charcoal, (9) safety precautions and environmental considerations, and (10) charcoal laboratory work. Each chapter lists references. There are four appendices.

  6. Continued studies of co-pumping of deuterium and helium on a single, 4K activated charcoal panel

    SciTech Connect

    Walthers, C.R.; Jenkins, E.M. ); Batzer, T.H. ); Sedgley, D.W. ); Konishi, S.; Ohira, S.; Naruse, Y. )

    1990-09-01

    The short program undertaken in 1989 to evaluate the feasibility of co-pumping deuterium and tritium (DT) and helium on a charcoal sorbent showed that the charcoal will indeed simultaneously pump the gases. Of interest also was the fact that the total accumulation of helium (capacity) was virtually identical in constant throughput runs in which the D{sub 2}/He ratio was changed between runs. The test program described in this paper undertaken to evaluate further the co-pumping capabilities of the charcoal sorbent.

  7. Impact of land-use and long-term (>150 years) charcoal accumulation on microbial activity, biomass and community structure in temperate soils (Belgium).

    NASA Astrophysics Data System (ADS)

    Hardy, Brieuc; Cornelis, Jean-Thomas; Dufey, Joseph E.

    2015-04-01

    In the last decade, biochar has been increasingly investigated as a soil amendment for long-term soil carbon sequestration while improving soil fertility. On the short term, biochar application to soil generally increases soil respiration as well as microbial biomass and activity and affects significantly the microbial community structure. However, such effects are relatively short-term and tend to vanish over time. In our study, we investigated the long-term impact of charcoal accumulation and land-use on soil biota in temperate haplic Luvisols developed in the loess belt of Wallonia (Belgium). Charcoal-enriched soils were collected in the topsoil of pre-industrial (>150 years old) charcoal kilns in forest (4 sites) and cropland (5 sites). The topsoil of the adjacent charcoal-unaffected soils was sampled in a comparable way. Soils were characterized (pH, total, organic and inorganic C, total N, exchangeable Ca, Mg, K, Na, cation exchange capacity and available P) and natural soil organic matter (SOM) and black carbon (BC) contents were determined by differential scanning calorimetry. After rewetting at pF 2.5, soils were incubated during 140 days at 20 °C. At 70 days of incubation, 10 g of each soil were freeze dried in order to measure total microbial biomass and community structure by PLFA analysis. The PLFA dataset was analyzed by principal component analysis (PCA) while soil parameters were used as supplementary variables. For both agricultural and forest soils, the respiration rate is highly related to the total microbial biomass (R²=0.90). Both soil respiration and microbial biomass greatly depend on the SOM content, which indicates that the BC pool is relatively inert microbiologically. Land-use explains most of the variance in the PLFA dataset, largely governing the first principal component of the ACP. In forest soils, we observe a larger proportion of gram + bacteria, actinomycetes and an increased bacteria:fungi ratio compared to cropland, where gram

  8. Novel Application of Confocal Laser Scanning Microscopy and 3D Volume Rendering toward Improving the Resolution of the Fossil Record of Charcoal

    PubMed Central

    Belcher, Claire M.; Punyasena, Surangi W.; Sivaguru, Mayandi

    2013-01-01

    Variations in the abundance of fossil charcoals between rocks and sediments are assumed to reflect changes in fire activity in Earth’s past. These variations in fire activity are often considered to be in response to environmental, ecological or climatic changes. The role that fire plays in feedbacks to such changes is becoming increasingly important to understand and highlights the need to create robust estimates of variations in fossil charcoal abundance. The majority of charcoal based fire reconstructions quantify the abundance of charcoal particles and do not consider the changes in the morphology of the individual particles that may have occurred due to fragmentation as part of their transport history. We have developed a novel application of confocal laser scanning microscopy coupled to image processing that enables the 3-dimensional reconstruction of individual charcoal particles. This method is able to measure the volume of both microfossil and mesofossil charcoal particles and allows the abundance of charcoal in a sample to be expressed as total volume of charcoal. The method further measures particle surface area and shape allowing both relationships between different size and shape metrics to be analysed and full consideration of variations in particle size and size sorting between different samples to be studied. We believe application of this new imaging approach could allow significant improvement in our ability to estimate variations in past fire activity using fossil charcoals. PMID:23977267

  9. Adsorption and desorption of noble gases on activated charcoal: II. sup 222 Rn studies in a monolayer and packed bed

    SciTech Connect

    Scarpitta, S.C.; Harley, N.H. )

    1990-10-01

    The adsorptive and desorptive characteristics of canisters containing a petroleum-based charcoal were investigated under controlled conditions of temperature, relative humidity, and Rn concentration. Charcoals exposed in a monolayer and packed bed during exposure intervals of 1-7 d demonstrate that Rn adsorption and desorption are dependent on bed depth and the amount of water adsorbed. Changes in the adsorptive and desorptive properties of the charcoal occurred near the break-point where the pores became occluded by water vapor that condenses in the entrance capillaries. Radon-222 adsorption is decreased by an order of magnitude as the amount of adsorbed water exceeds the break-point of the charcoal. The reduction in pore surface due to adsorbed water results in a marked increase in the rate of Rn loss from exposed canisters, accounting for reduced adsorption. The apparent desorption time-constant for a 2-cm bed of loose Witco 6 x 10 mesh charcoal containing 0.220-0.365 kg H{sub 2}O kg-1 is typically between 2-8 h. The apparent desorption time-constant for an equivalent packed bed containing a water vapor content of 0.026-0.060 kg H{sub 2}O kg-1, which is below the break-point of the charcoal, is about 15-30 h. Conventional charcoal canisters, if exposed in the fully-opened configuration, can achieve the break-point in less than 4 d at 70% humidity. The use of a diffusion barrier would allow for longer exposure times until the break-point of the charcoal is achieved.

  10. Rapid Active Sampling Package

    NASA Technical Reports Server (NTRS)

    Peters, Gregory

    2010-01-01

    A field-deployable, battery-powered Rapid Active Sampling Package (RASP), originally designed for sampling strong materials during lunar and planetary missions, shows strong utility for terrestrial geological use. The technology is proving to be simple and effective for sampling and processing materials of strength. Although this originally was intended for planetary and lunar applications, the RASP is very useful as a powered hand tool for geologists and the mining industry to quickly sample and process rocks in the field on Earth. The RASP allows geologists to surgically acquire samples of rock for later laboratory analysis. This tool, roughly the size of a wrench, allows the user to cut away swaths of weathering rinds, revealing pristine rock surfaces for observation and subsequent sampling with the same tool. RASPing deeper (.3.5 cm) exposes single rock strata in-situ. Where a geologist fs hammer can only expose unweathered layers of rock, the RASP can do the same, and then has the added ability to capture and process samples into powder with particle sizes less than 150 microns, making it easier for XRD/XRF (x-ray diffraction/x-ray fluorescence). The tool uses a rotating rasp bit (or two counter-rotating bits) that resides inside or above the catch container. The container has an open slot to allow the bit to extend outside the container and to allow cuttings to enter and be caught. When the slot and rasp bit are in contact with a substrate, the bit is plunged into it in a matter of seconds to reach pristine rock. A user in the field may sample a rock multiple times at multiple depths in minutes, instead of having to cut out huge, heavy rock samples for transport back to a lab for analysis. Because of the speed and accuracy of the RASP, hundreds of samples can be taken in one day. RASP-acquired samples are small and easily carried. A user can characterize more area in less time than by using conventional methods. The field-deployable RASP used a Ni

  11. Heavy metal removal from MSWI fly ash by electrokinetic remediation coupled with a permeable activated charcoal reactive barrier

    PubMed Central

    Huang, Tao; Li, Dongwei; Kexiang, Liu; Zhang, Yuewei

    2015-01-01

    This paper presents the investigations into the feasibility of the application of a remediation system that couples electrokinetic remediation (EKR) with the permeable reactive barrier (PRB) concept for municipal solid waste incineration (MSWI) fly ash with activated charcoal as the PRB material. The experimental results of this study showed that the proposed combined method can effectively improve the remediation efficiency and that the addition of the oxalic acid to the PRB media before the coupled system can further enhance the remediation process. In the optimization tests, the maximum removals of Zn, Pb, Cu and Cd were achieved under different experimental conditions. The voltage gradient and processing time were shown to have significant effects on the removal of Cu and Cd, whereas the addition of the oxalic acid had a more significant influence on the removal of Pb. Generally, the processing time is the most significant factor in changing the removal rates of HMs in the enhanced coupled system. In terms of the leaching toxicity, the specimen remediated by ENEKR + PRB showed the lowest leaching value for each HM in the S2 and S3 regions. PMID:26486449

  12. Heavy metal removal from MSWI fly ash by electrokinetic remediation coupled with a permeable activated charcoal reactive barrier

    NASA Astrophysics Data System (ADS)

    Huang, Tao; Li, Dongwei; Kexiang, Liu; Zhang, Yuewei

    2015-10-01

    This paper presents the investigations into the feasibility of the application of a remediation system that couples electrokinetic remediation (EKR) with the permeable reactive barrier (PRB) concept for municipal solid waste incineration (MSWI) fly ash with activated charcoal as the PRB material. The experimental results of this study showed that the proposed combined method can effectively improve the remediation efficiency and that the addition of the oxalic acid to the PRB media before the coupled system can further enhance the remediation process. In the optimization tests, the maximum removals of Zn, Pb, Cu and Cd were achieved under different experimental conditions. The voltage gradient and processing time were shown to have significant effects on the removal of Cu and Cd, whereas the addition of the oxalic acid had a more significant influence on the removal of Pb. Generally, the processing time is the most significant factor in changing the removal rates of HMs in the enhanced coupled system. In terms of the leaching toxicity, the specimen remediated by ENEKR + PRB showed the lowest leaching value for each HM in the S2 and S3 regions.

  13. Heavy metal removal from MSWI fly ash by electrokinetic remediation coupled with a permeable activated charcoal reactive barrier.

    PubMed

    Huang, Tao; Li, Dongwei; Kexiang, Liu; Zhang, Yuewei

    2015-01-01

    This paper presents the investigations into the feasibility of the application of a remediation system that couples electrokinetic remediation (EKR) with the permeable reactive barrier (PRB) concept for municipal solid waste incineration (MSWI) fly ash with activated charcoal as the PRB material. The experimental results of this study showed that the proposed combined method can effectively improve the remediation efficiency and that the addition of the oxalic acid to the PRB media before the coupled system can further enhance the remediation process. In the optimization tests, the maximum removals of Zn, Pb, Cu and Cd were achieved under different experimental conditions. The voltage gradient and processing time were shown to have significant effects on the removal of Cu and Cd, whereas the addition of the oxalic acid had a more significant influence on the removal of Pb. Generally, the processing time is the most significant factor in changing the removal rates of HMs in the enhanced coupled system. In terms of the leaching toxicity, the specimen remediated by ENEKR + PRB showed the lowest leaching value for each HM in the S2 and S3 regions. PMID:26486449

  14. Emissions of air pollutants from indoor charcoal barbecue.

    PubMed

    Huang, Hsiao-Lin; Lee, Whei-May Grace; Wu, Feng-Shu

    2016-01-25

    Ten types of commercial charcoal commonly used in Taiwan were investigated to study the potential health effects of air pollutants generated during charcoal combustion in barbecue restaurants. The charcoal samples were combusted in a tubular high-temperature furnace to simulate the high-temperature charcoal combustion in barbecue restaurants. The results indicated that traditional charcoal has higher heating value than green synthetic charcoal. The amount of PM10 and PM2.5 emitted during the smoldering stage increased when the burning temperature was raised. The EF for CO and CO2 fell within the range of 68-300 and 644-1225 g/kg, respectively. Among the charcoals, the lowest EF for PM2.5 and PM10 were found in Binchōtan (B1). Sawdust briquette charcoal (I1S) emitted the smallest amount of carbonyl compounds. Charcoal briquettes (C2S) emitted the largest amount of air pollutants during burning, with the EF for HC, PM2.5, PM10, formaldehyde, and acetaldehyde being the highest among the charcoals studied. The emission of PM2.5, PM10, formaldehyde, and acetaldehyde were 5-10 times those of the second highest charcoal. The results suggest that the adverse effects of the large amounts of air pollutants generated during indoor charcoal combustion on health and indoor air quality must not be ignored. PMID:26476306

  15. [The use of Dnipro activated charcoal filamentous material in performing extracorporeal sorption detoxification].

    PubMed

    Popov, V D; Serheiev, V P; Sobko, I V; Litvinov, V F

    1998-01-01

    Experimental estimation of properties of an activated carbonic fibrillar material "Dnipro" was conducted. Its application perspectivity while conduction of plasmo-, lympho- and hemosorption was proved. PMID:10050405

  16. Activation of waste MDF sawdust charcoal and its reactive dye adsorption characteristics.

    PubMed

    Gan, Q; Allen, S J; Matthews, R

    2004-01-01

    This paper reports an experimental investigation of converting waste medium density fibreboard (MDF) sawdust into chars and activated carbon using chemical activation and thermal carbonisation processes. The MDF sawdust generated during the production of architectural mouldings was characterised and found to have unique properties in terms of fine particle size and high particle density. It also has a high content of urea formaldehyde resin used as a binder in the manufacturing of MDF board. Direct thermal carbonisation and chemical activation of the sawdust by metal impregnation and acid (phosphoric acid) treatment prior to pyrolysis treatment were carried out. The surface morphology of the raw dust, its chars and activated carbon were examined using scanning electron microscopy (SEM). Adsorptive properties and total pore volume of the materials were also analysed using the BET nitrogen adsorption method. Liquid adsorption of a reactive dye (Levafix Brilliant red E-4BA) by the derived sawdust carbon was investigated in batch isothermal adsorption process and the results compared to adsorption on to a commercial activated carbon (Filtrasorb F400). The MDF sawdust carbon exhibited in general a very low adsorption capacity towards the reactive dye, and physical characterisation of the carbon revealed that the conventional chemical activation and thermal carbonisation process were ineffective in developing a microporous structure in the dust particles. The small size of the powdery dust, the high particle density, and the presence of the urea formaldehyde resin all contributed to the difficulty of developing a proper porous structure during the thermal and chemical activation process. Finally, activation of the dust material in a consolidated form (cylindrical pellet) only achieved very limited improvement in the dye adsorption capacity. This original study, reporting some unexpected outcomes, may serve as a stepping-stone for future investigations of recycle and

  17. Correction of deposit ages for inherited ages of charcoal: implications for sediment dynamics inferred from random sampling of deposits on headwater valley floors

    NASA Astrophysics Data System (ADS)

    Frueh, W. Terry; Lancaster, Stephen T.

    2014-03-01

    Inherited age is defined herein as the difference between times of carbon fixation in a material and deposition of that material within sediments from which it is eventually sampled in order to estimate deposit age via radiocarbon dating. Inheritance generally leads to over-estimation of the age by an unknown amount and therefore represents unquantified bias and uncertainty that could potentially lead to erroneous inferences. Inherited ages in charcoal are likely to be larger, and therefore detectable relative to analytic error, where forests are dominated by longer-lived trees, material is stored for longer periods upslope, and downstream post-fire delivery of that material is dominated by mass movements, such as in the near-coastal mountains of northwestern North America. Inherited age distribution functions were estimated from radiocarbon dating of 126 charcoal pieces from 14 stream-bank exposures of debris-flow deposits, fluvial fines, and fluvial gravels along a headwater stream in the southern Oregon Coast Range, USA. In the region, these 3 facies are representative of the nearly continuous coalescing fan-fill complexes blanketing valley floors of headwater streams where the dominant transport mechanism shifts from debris-flow to fluvial. Within each depositional unit, and for each charcoal piece within that unit, convolution of the calibrated age distribution with that of the youngest piece yielded an inherited age distribution for the unit. Fits to the normalized sums of inherited age distributions for units of like facies provided estimates of facies-specific inherited age distribution functions. Finally, convolution of these distribution functions with calibrated deposit age distributions yielded corrections to published valley-floor deposit ages and residence time distributions from nearby similar sites. Residence time distributions were inferred from the normalized sums of distributions of ˜30 deposit ages at each of 4 sites: 2 adjacent valley reaches

  18. Gasification of blended animal manures to produce synthesis gas and activated charcoal

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blended swine solids, chicken litter, and hardwood are renewable and expensive sources to produce combined heat and power (CHP), fuels and related chemicals. The therrmochemical pathway to gasify manure has the added advantage of destroying harmful pathogens and pharmaceutically active compounds dur...

  19. Soil charcoal to assess the impacts of past human disturbances on tropical forests.

    PubMed

    Vleminckx, Jason; Morin-Rivat, Julie; Biwolé, Achille B; Daïnou, Kasso; Gillet, Jean-François; Doucet, Jean-Louis; Drouet, Thomas; Hardy, Olivier J

    2014-01-01

    The canopy of many central African forests is dominated by light-demanding tree species that do not regenerate well under themselves. The prevalence of these species might result from ancient slash-and-burn agricultural activities that created large openings, while a decline of these activities since the colonial period could explain their deficit of regeneration. To verify this hypothesis, we compared soil charcoal abundance, used as a proxy for past slash-and-burn agriculture, and tree species composition assessed on 208 rainforest 0.2 ha plots located in three areas from Southern Cameroon. Species were classified in regeneration guilds (pioneer, non-pioneer light-demanding, shade-bearer) and characterized by their wood-specific gravity, assumed to reflect light requirement. We tested the correlation between soil charcoal abundance and: (i) the relative abundance of each guild, (ii) each species and family abundance and (iii) mean wood-specific gravity. Charcoal was found in 83% of the plots, indicating frequent past forest fires. Radiocarbon dating revealed two periods of fires: "recent" charcoal were on average 300 years old (up to 860 BP, n = 16) and occurred in the uppermost 20 cm soil layer, while "ancient" charcoal were on average 1900 years old (range: 1500 to 2800 BP, n = 43, excluding one sample dated 9400 BP), and found in all soil layers. While we expected a positive correlation between the relative abundance of light-demanding species and charcoal abundance in the upper soil layer, overall there was no evidence that the current heterogeneity in tree species composition can be explained by charcoal abundance in any soil layer. The absence of signal supporting our hypothesis might result from (i) a relatively uniform impact of past slash-and-burn activities, (ii) pedoturbation processes bringing ancient charcoal to the upper soil layer, blurring the signal of centuries-old Human disturbances, or (iii) the prevalence of other environmental

  20. Bamboo charcoal as adsorbent for SPE coupled with monolithic column-HPLC for rapid determination of 16 polycyclic aromatic hydrocarbons in water samples.

    PubMed

    Ma, Jiping; Li, Mo; Li, Jinhua; Rui, Cuijie; Xin, Yanping; Xue, Qinzhao; Chen, Lingxin

    2011-10-01

    The coupling of solid-phase extraction (SPE) using bamboo charcoal (BC) as an adsorbent with a monolithic column-high performance liquid chromatography (MC-HPLC) method was developed for the high-efficiency enrichment and rapid determination of 16 polycyclic aromatic hydrocarbons (PAHs) in water. Key influence factors, such as the type and the volume of the elution solvent, and the flow rate and the volume of the sample loading, were optimized to obtain a high SPE recovery and extraction efficiency. BC as an SPE adsorbent presented a high extraction efficiency due to its large specific surface area and high adsorption capacity; MC as an HPLC column accelerated the separation within 8 min because of its high porosity, fast mass transfer, and low-pressure resistance. The calibration curves for the PAHs extracted were linear in the range of 0.2-15 µg/L, with the correlation coefficients (r(2)) between 0.9970-0.9999. This method attained good precisions (relative standard deviation, RSD) from 3.5 to 10.9% for the standard PAHs I aqueous solutions at 5 µg/L; the method recoveries ranged in 52.6-121.6% for real spiked river water samples with 0.4 and 4 µg/L. The limits of detection (LODs, S/N = 3) of the method were determined from 11 and 87 ng/L. The developed method was demonstrated to be applicable for the rapid and sensitive determination of 16 PAHs in real environmental water samples. PMID:22586244

  1. Activated-charcoal filters: water treatment, pollution control, and industrial applications. January 1970-July 1988 (citations from the US Patent data base). Report for January 1970-July 1988

    SciTech Connect

    Not Available

    1988-08-01

    This bibliography contains citations of selected patents concerning activated-charcoal filters and their applications in water treatment, pollution control, and industrial processes. Filtering methods and equipment for air and water purification, industrial distillation and extraction, industrial leaching, and filtration of toxic gases and pollutants are described. Applications include drinking water purification, filtering beverages, production of polymer materials, solvent and metal recovery, swimming pool filtration, waste conversion, automobile fuel and exhaust systems, and footwear deodorizing. (Contains 129 citations fully indexed and including a title list.)

  2. Activated charcoal filters: Water treatment, pollution control, and industrial applications. (Latest citations from the Patent Bibliographic database with exemplary claims. ) Published Search

    SciTech Connect

    Not Available

    1993-08-01

    The bibliography contains citations of selected patents concerning activated charcoal filters and their applications in water treatment, pollution control, and industrial processes. Filtering methods and equipment for air and water purification, industrial distillation and extraction, industrial leaching, and filtration of toxic materials and contaminants are described. Applications include drinking water purification, filtering beverages, production of polymer materials, solvent and metal recovery, waste conversion, automotive fuel and exhaust systems, swimming pool filtration, tobacco smoke filters, kitchen ventilators, medical filtration treatment, and odor absorbing materials. (Contains 250 citations and includes a subject term index and title list.)

  3. Activated charcoal filters: Water treatment, pollution control, and industrial applications. (Latest citations from the US Patent Bibliographic File with exemplary claims). Published Search

    SciTech Connect

    Not Available

    1994-06-01

    The bibliography contains citations of selected patents concerning activated charcoal filters and their applications in water treatment, pollution control, and industrial processes. Filtering methods and equipment for air and water purification, industrial distillation and extraction, and filtration of toxic materials and contaminants are described. Applications are discussed, including drinking water purification, air and water pollution control, manufacture of industrial materials, materials recovery, waste treatment, automotive fuel and exhaust systems, cigarette filters, ventilation systems, medical filtration, and odor absorbing materials. (Contains a minimum of 125 citations and includes a subject term index and title list.)

  4. Activated charcoal filters: Water treatment, pollution control, and industrial applications. (Latest citations from the US Patent Bibliographic file with exemplary claims). Published Search

    SciTech Connect

    1996-01-01

    The bibliography contains citations of selected patents concerning activated charcoal filters and their applications in water treatment, pollution control, and industrial processes. Filtering methods and equipment for air and water purification, industrial distillation and extraction, and filtration of toxic materials and contaminants are described. Applications are discussed, including drinking water purification, air and water pollution control, manufacture of industrial materials, materials recovery, waste treatment, automotive fuel and exhaust systems, cigarette filters, ventilation systems, medical filtration, and odor absorbing materials. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  5. A Novel Activated-Charcoal-Doped Multiwalled Carbon Nanotube Hybrid for Quasi-Solid-State Dye-Sensitized Solar Cell Outperforming Pt Electrode.

    PubMed

    Arbab, Alvira Ayoub; Sun, Kyung Chul; Sahito, Iftikhar Ali; Qadir, Muhammad Bilal; Choi, Yun Seon; Jeong, Sung Hoon

    2016-03-23

    Highly conductive mesoporous carbon structures based on multiwalled carbon nanotubes (MWCNTs) and activated charcoal (AC) were synthesized by an enzymatic dispersion method. The synthesized carbon configuration consists of synchronized structures of highly conductive MWCNT and porous activated charcoal morphology. The proposed carbon structure was used as counter electrode (CE) for quasi-solid-state dye-sensitized solar cells (DSSCs). The AC-doped MWCNT hybrid showed much enhanced electrocatalytic activity (ECA) toward polymer gel electrolyte and revealed a charge transfer resistance (RCT) of 0.60 Ω, demonstrating a fast electron transport mechanism. The exceptional electrocatalytic activity and high conductivity of the AC-doped MWCNT hybrid CE are associated with its synchronized features of high surface area and electronic conductivity, which produces higher interfacial reaction with the quasi-solid electrolyte. Morphological studies confirm the forms of amorphous and conductive 3D carbon structure with high density of CNT colloid. The excessive oxygen surface groups and defect-rich structure can entrap an excessive volume of quasi-solid electrolyte and locate multiple sites for iodide/triiodide catalytic reaction. The resultant D719 DSSC composed of this novel hybrid CE fabricated with polymer gel electrolyte demonstrated an efficiency of 10.05% with a high fill factor (83%), outperforming the Pt electrode. Such facile synthesis of CE together with low cost and sustainability supports the proposed DSSCs' structure to stand out as an efficient next-generation photovoltaic device. PMID:26911208

  6. The addition of charcoals to broiler diets did not alter the recovery of Salmonella Typhimurium during grow-out.

    PubMed

    Wilson, K M; Bourassa, D V; Davis, A J; Freeman, M E; Buhr, R J

    2016-03-01

    Two experiments evaluated prebiotics added to feed on the recovery of Salmonella in broilers during grow-out and processing. In Experiment 1, "seeder" chicks were inoculated with Salmonella Typhimurium and placed with penmates. Treatments were: basal control diet, added 0.3% bamboo charcoal, 0.6% bamboo charcoal, or 0.12% Aromabiotic (medium chain fatty acids). The ceca from seeders and penmates were sampled to confirm Salmonella colonization at 3, 4, and 6 wk, and pen litter was sampled weekly. At 3 wk, charcoal fed chicks had significantly lower cecal recovery (37% lower) of Salmonella via direct plating but no differences at wk 4 or 6. At 6 wk, broilers fed Aromabiotic had no recovery of Salmonella from ceca with direct plating and significantly, 18%, lower recovery with enrichment. In Experiment 2, the treatments were: basal control diet, added 0.3% bamboo charcoal, 0.3% activated bamboo charcoal, or 0.3% pine charcoal. At placement, 2 seeders were challenged with Salmonella and commingled with penmates and ceca sampled at 1 and 2 wk, and ceca from 5 penmates/pen at 3 to 6 wk. Weekly, the pH of the crop and duodenum was measured from 1 penmate/pen and the litter surface sampled. At the end of grow-out broilers were processed. Results showed that penmates had colonized at 1 and 2 wk. Cecal Salmonella showed no differences except at 4 wk, when activated bamboo charcoal had a 18% lower recovery of Salmonella (enrichment) compared to the control (88%). Similar to Experiment 1, the recovery of Salmonella from the litter was not significantly different among treatments, however an overall decrease in recovery by 4 wk with direct plating reoccurred. The pH of the duodenum and the crop were not different among treatments. Crop pH (6.0) for all treatments were significantly higher at wk 1 compared to wk 2 to 6. Charcoals had minimal effect on Salmonella recovery in the ceca, but following defeathering, broilers fed charcoals had significantly lower Salmonella

  7. Charcoal deposition and redeposition in Elk Lake, Minnesota, USA

    USGS Publications Warehouse

    Platt, Bradbury J.

    1996-01-01

    Sedimentary charcoal, diatom and phytolith records of the past 1500 years at Elk Lake, Minnesota, in combination with sediment trap studies and a transect of surface sediment samples, document the mechanisms by which previously deposited charcoal is redeposited and finally buried in this lake. The frequent correspondence of high diatom concentrations and peaks of phytolith and charcoal fragments suggest that currents and turbulence related to lake circulation are responsible for winnowing charcoal and phytoliths from shallow water depositional sites to deeper areas of the lake. High diatom concentrations in the record relate to increased nutrient fluxes also supplied by circulation. Despite the fact that the watershed and area around Elk Lake has not been burned since AD 1922, charcoal continues to reach the profundal zone from littoral source areas in Elk Lake. The variable redeposition of within-lake charcoal requires evaluation before fire-history records can be related to global, regional or even local fire events.

  8. paleofire: An R package to analyse sedimentary charcoal records from the Global Charcoal Database to reconstruct past biomass burning

    NASA Astrophysics Data System (ADS)

    Blarquez, Olivier; Vannière, Boris; Marlon, Jennifer R.; Daniau, Anne-Laure; Power, Mitchell J.; Brewer, Simon; Bartlein, Patrick J.

    2014-11-01

    We describe a new R package, paleofire, for analysis and synthesis of charcoal time series, such as those contained in the Global Charcoal Database (GCD), that are used to reconstruct paleofire activity (past biomass burning). paleofire is an initiative of the Global Paleofire Working Group core team (www.gpwg.org), whose aim is to encourage the use of sedimentary charcoal series to develop regional-to-global syntheses of paleofire activity, and to enhance access to the GCD data by providing a common research framework. Currently, paleofire features are organized into three different parts related to (i) site selection and charcoal series extraction from the GCD; (ii) charcoal data transformation; and (iii) charcoal series compositing and synthesis. We provide a technical description of paleofire and describe some new implementations such as the circular block bootstrap procedure. We tested the software using GCDv3 data from eastern North America, and provide examples of interpreting results of regional and global syntheses.

  9. Active submarine volcano sampled

    USGS Publications Warehouse

    Taylor, B.

    1983-01-01

    On June 4, 1982, two full dredge hauls of fresh lava were recovered from the upper flanks of Kavachi submarine volcano, Solomon Islands, in the western Pacific Ocean, from the water depths of 1,200 and 2,700 feet. the shallower dredge site was within 0.5 mile of the active submarine vent shown at the surface by an area of slick water, probably caused by gas emissions. Kavachi is a composite stratovolcano that has been observed to erupt every year or two for at least the last 30 years (see photographs). An island formed in 1952, 1961, 1965, and 1978; but, in each case, it rapidly eroded below sea level. The latest eruption was observed by Solair pilots during the several weeks up to and including May 18, 1982. 

  10. Charcoal filter testing

    SciTech Connect

    Lyons, J.

    1997-08-01

    In this very brief, informal presentation, a representative of the US Nuclear Regulatory Commission outlines some problems with charcoal filter testing procedures and actions being taken to correct the problems. Two primary concerns are addressed: (1) the process to find the test method is confusing, and (2) the requirements of the reference test procedures result in condensation on the charcoal and causes the test to fail. To address these problems, emergency technical specifications were processed for three nuclear plants. A generic or an administrative letter is proposed as a more permanent solution. 1 fig.

  11. Paracetamol biodegradation by activated sludge and photocatalysis and its removal by a micelle-clay complex, activated charcoal, and reverse osmosis membranes.

    PubMed

    Karaman, Rafik; Khamis, Mustafa; Abbadi, Jehad; Amro, Ahmad; Qurie, Mohannad; Ayyad, Ibrahim; Ayyash, Fatima; Hamarsheh, Omar; Yaqmour, Reem; Nir, Shlomo; Bufo, Sabino A; Scrano, Laura; Lerman, Sofia; Gur-Reznik, Shirra; Dosoretz, Carlos G

    2016-10-01

    Kinetic studies on the stability of the pain killer paracetamol in Al-Quds activated sludge demonstrated that paracetamol underwent biodegradation within less than one month to furnish p-aminophenol in high yields. Characterizations of bacteria contained in Al-Quds sludge were accomplished. It was found that Pseudomonas aeruginosa is the bacterium most responsible for the biodegradation of paracetamol to p-aminophenol and hydroquinone. Batch adsorptions of paracetamol and its biodegradation product (p-aminophenol) by activated charcoal and a composite micelle (octadecyltrimethylammonium)-clay (montmorillonite) were determined at 25°C. Adsorption was adequately described by a Langmuir isotherm, and indicated better efficiency of removal by the micelle-clay complex. The ability of bench top reverse osmosis (RO) plant as well as advanced membrane pilot plant to remove paracetamol was also studied at different water matrixes to test the effect of organic matter composition. The results showed that at least 90% rejection was obtained by both plants. In addition, removal of paracetamol from RO brine was investigated by using photocatalytic processes; optimal conditions were found to be acidic or basic pH, in which paracetamol degraded in less than 5 min. Toxicity studies indicated that the effluent and brine were not toxic except for using extra low energy membrane which displayed a half maximal inhibitory concentration (IC-50) value of 80%. PMID:26852629

  12. Nondestructive neutron activation analysis of volcanic samples: Hawaii

    SciTech Connect

    Zoller, W.H.; Finnegan, D.L.; Crowe, B.

    1986-01-01

    Samples of volcanic emissions have been collected between and during eruptions of both Kilauea and Mauna Loa volcanoes during the last three years. Airborne particles have been collected on Teflon filters and acidic gases on base-impregnated cellulose filters. Chemically neutral gas-phase species are collected on charcoal-coated cellulose filters. The primary analytical technique used is nondestructive neutron activation analysis, which has been used to determine the quantities of up to 35 elements on the different filters. The use of neutron activation analysis makes it possible to analyze for a wide range of elements in the different matrices used for the collection and to learn about the distribution between particles and gas phases for each of the elements.

  13. [Adsorption mechanism of furfural onto modified rice husk charcoals].

    PubMed

    Deng, Yong; Wang, Xianhua; Li, Yunchao; Shao, Jing'ai; Yang, Haiping; Chen, Hanping

    2015-10-01

    To evaluate the absorptive characteristics of furfural onto biomass charcoals derived from rice husk pyrolysis, we studied the information of the structure and surface chemistry properties of the rice husk charcoals modified by thermal treatment under nitrogen and carbon dioxide flow and adsorption mechanism of furfural. The modified samples are labeled as RH-N2 and RH-CO2. Fresh rice husk charcoal sample (RH-450) and modified samples were characterized by elemental analysis, nitrogen adsorption-desorption isotherms, Fourier-transform infrared spectroscopy and Boehm titration. The results show that fresh rice husk charcoal obtained at 450 degrees C had a large number of organic groups on its surface and poor pore structure. After the modification under nitrogen and carbon dioxide flow, oxygenic organics in rice husk charcoals decompose further, leading to the reduction of acidic functional groups on charcoals surface, and the increase of the pyrone structures of the basic groups. Meanwhile, pore structure was improved significantly and the surface area was increased, especially for the micropores. This resulted in the increase of π-π dispersion between the surfaces of rice husk charcoals and furfural molecular. With making comprehensive consideration of π-π dispersion and pore structure, the best removal efficiency of furfural was obtained by rice husk charcoal modified under carbon dioxide flow. PMID:26964338

  14. Microscopic charcoal as a fossil indicator of fire

    NASA Astrophysics Data System (ADS)

    Patterson, William A.; Edwards, Kevin J.; Maguire, David J.

    Charcoal preserved in lake sediments, peat, and soils provides a record of past fire occurrence. An understanding of fire history is important in evaluating interactions between vegetation, climate and human disturbances through at least the last several millennia. In this paper we review information concerning the production, dispersal, sedimentation and preservation of charcoal. We present examples of studies that have used charcoal analysis in palaeoecological reconstructions, with special emphasis on analytical techniques and problems of interpretation. Unlike pollen, which is produced continuously in fairly constant amounts, charcoal is produced in large quantities but at irregular intervals. These are a function of fire regimes that are often unique to specific vegetation types and/or climatic regions. Charcoal particles vary in size from sub-microscopic to macroscopic, with small particles presumably being transported further by wind and water than large particles. Charcoal preserves well, but it may be subject to breakage, especially when transported by water. We present theoretical models of dispersal and discuss potential problems associated with post-depositional mixing. A variety of charcoal analysis techniques have been employed during the past four decades. Most involve microscopic identification and quantification of numbers or size of individual fragments occurring in samples prepared for pollen analysis. The most commonly used method — estimating charcoal area by categorizing particles in several size classes — is both tedious and time consuming, and recently introduced techniques attempt to estimate past fire occurrence based upon point count estimation, elemental carbon analysis, magnetic measurement of sediments, electron microscope, and spectrographic analyses. A lack of standardization both within and among analysis techniques has hampered interpretation of charcoal profiles. Taphonomic processes affecting charcoal are less well understood

  15. Metal content of charcoal in mining-impacted wetland sediments.

    PubMed

    Baker, Leslie L; Strawn, Daniel G; Rember, William C; Sprenke, Kenneth F

    2011-01-01

    Charcoal is well known to accumulate contaminants, but its association with metals and other toxic elements in natural settings has not been well studied. Association of contaminants with charcoal in soil and sediment may affect their mobility, bioavailability, and fate in the environment. In this paper, natural wildfire charcoal samples collected from a wetland site that has been heavily contaminated by mine waste were analyzed for elemental contents and compared to the surrounding soil. Results showed that the charcoal particles were enriched over the host soils by factors of two to 40 times in all contaminant elements analyzed. Principal component analysis was carried out on the data to determine whether element enrichment patterns in the soil profile charcoal are related to those in the soils. The results suggest that manganese and zinc concentrations in charcoal are controlled by geochemical processes in the surrounding soil, whereas the concentrations of arsenic, lead, zinc, iron, phosphorus, and sulfur in charcoal are unrelated to those in the surrounding soil. This study shows evidence that charcoal in soils can have a distinct and important role in controlling contaminant speciation and fate in the environment. PMID:21093017

  16. Dynamics and functions of bacterial communities in bark, charcoal and sand filters treating greywater.

    PubMed

    Dalahmeh, Sahar S; Jönsson, Håkan; Hylander, Lars D; Hui, Nan; Yu, Dan; Pell, Mikael

    2014-05-01

    This study explored the effects of greywater application on the dynamics and functions of biofilms developed in bark, activated charcoal and sand filters used for removal of organic matter and nitrogen. Duplicate columns (20 cm diameter, 60 cm deep) were packed with bark, charcoal or sand with effective size 1.4 mm and uniformity coefficient 2.2, and dosed with 32 L m(-2) day(-1) of an artificial greywater (14 g BOD5 m(-2) day(-1)) for 116 days. Potential respiration rate (PRR), determined in filter samples after addition of excess glucose, and bacterial diversity and composition, analysed by 454-pyrosequencing of bacterial 16S ribosomal DNA, were measured at different times and depths in the filters. The bark and charcoal filters were more efficient in removing BOD5 than the sand (98, 97% and 75%, respectively). The highest PRR in the 0-2 cm layer of the columns on day 84 was found in the bark filters, followed by the charcoal and sand filters (632 ± 66, 222 ± 34 and 56 ± 2 mg O2 L(-1), respectively; n = 2). Bacterial community in the bark filters showed the highest richness. The charcoal and sand filters both developed more diverse and dynamic (changing over time and depth) bacterial communities than the bark. In addition to the greywater, the lignocelluosic composition of the bark and its lower pH probably selected for the bacterial community structure and the organic content provided additional substrate, as shown by its higher PRR and its different nitrifying bacterial genera. In the oligotrophic charcoal and sand, the composition of the greywater itself defined the bacterial community. Thus, the initially low bacterial biomass in the latter filters was enriched over time, allowing a diversified bacterial community to develop. The top layers of the bark and charcoal filters displayed a high dominance of Rhizobium, Pseudomonas and Acinetobacter, which were less evident in the 60 cm layer, whereas in the sand filters these genera were

  17. Generation rate of carbon monoxide from burning charcoal.

    PubMed

    Ojima, Jun

    2011-01-01

    Charcoal, often used as cooking fuel at some restaurants, generates a significant amount of carbon monoxide (CO) during its combustion. Every year in Japan, a number of cooks and waiters/waitresses are poisoned by CO emanating from burning charcoal. Although certain ventilation is necessary to prevent the accumulation of CO, it is difficult to estimate the proper ventilation requirement for CO because the generation rate of CO from burning charcoal has not been established. In this study, several charcoals were evaluated in terms of CO generation rate. Sample charcoals were burned in a cooking stove to generate exhaust gas. For each sample, four independent variables -- the mass of the sample, the flow rate of the exhaust gas, CO concentration in the exhaust gas and the combustion time of the sample -- were measured, and the CO generation rate was calculated. The generation rate of CO from the charcoal was shown to be 137-185 ml/min/kW. Theoretical ventilation requirements for charcoals to prevent CO poisoning are estimated to be 41.2-55.6 m(3)/h/kW. PMID:21372432

  18. Effects of historic charcoal burning on soil properties

    NASA Astrophysics Data System (ADS)

    Hirsch, Florian; Schneider, Anna; Raab, Alexandra; Raab, Thomas; Buras, Allan; van der Maaten, Ernst; Takla, Melanie; Räbiger, Christin; Cruz Garcia, Roberto; Wilmking, Martin

    2015-04-01

    In Northeastern Germany the production of ironware between the 16th and 19th century left behind a remarkable amount of charcoal kiln remains. At the study site in the forests north of Cottbus, Rubic Brunic Arenosols are developed on Weichselian glaciofluvial deposits. Remote sensing surveys, underpinned by archaeological studies, show that charcoal was gained from several thousand kilns. The round charcoal kiln remains with inner diameters up to 20 m are smooth platforms elevated a few decimeters higher than the surrounding area. The remaining mounds consist of an about 40 cm thick sheet containing residuals of the charcoal production process such as charcoal fragments, ash but also organic material covering the Rubic Brunic Arenosols. The charcoal kiln remains are distanced only up to 100 m from each other. For the 32 square kilometers large study site, the ground area covered by such charcoal production residuals is about 0.5 square kilometer, i.e. 1.5% of the study area. The charcoal kiln sites are a remarkable carbon accumulator on the sandy parent material. Against this background, we aim to characterize the effects of pyrolysis and the enrichment of carbon, induced by the charcoal production, on soil properties. Field work was done during archaeological rescue excavations on three charcoal kiln relicts having diameters of about 15 m. We applied 150 l of Brilliant Blue solution on six 1 square meter plots (three inside, three outside of the charcoal kiln mound) and afterwards trenched horizontal and vertical profiles for recording the staining patterns. Undisturbed soil samples to study soil micromorphology and further undisturbed samples for characterizing soil physical and hydraulic properties were taken. Outside of the charcoal kiln remain the Brilliant Blue solution drained within less than 10 minutes, whereas on the charcoal kiln remains the draining took between 20 and 40 minutes. Preliminary laboratory analyses underline the findings from the field and

  19. Impact of ancient charcoal kilns on chemical properties of several forest soils after 2 centuries

    NASA Astrophysics Data System (ADS)

    Dufey, Joseph; Hardy, Brieuc; Cornelis, Jean-Thomas

    2014-05-01

    Pyrogenic carbon plays a major role in soil biogeochemical processes and carbon budgets. Until the early 19th century, charcoal was the unique combustible used for iron metallurgy in Wallonia (Belgium). Traditional charcoal kilns were built directly in the forest: wood logs were piled into a mound and isolated from air oxygen with a covering of vegetation residues and soil before setting fire, inducing wood pyrolysis. Nowadays, ancient wood-charring platforms are still easy to identify on the forest floor as heightened domes of 10 meters in diameter characterized by a very dark topsoil horizon containing charcoal dust and fragments. Our goal is to assess the effects of wood charring at mound kiln sites on the properties of various forest soil types in Wallonia (Belgium), after two centuries. We sampled soil by horizon in 18 ancient kiln sites to 1.20 meter depth. The adjacent charcoal-unaffected soils were sampled the same way. We also collected recent charcoal fragments and topsoil samples from a still active charcoal kiln located close to Dole (France) to apprehend the evolution of soil properties over time. The pH, total carbon (C) and nitrogen (N) content, available phosphorus (Pav), cation exchange capacity at pH 7 (CEC), exchangeable cations (Ca++, Mg++, K+, Na+) and loss on ignition at 550°C (LI550) were measured on each soil sample. We separated the soil profiles in 5 groups based on the nature of soil substrate and pedogenesis for interpretation of the results. We show that the total carbon stock is significantly increased at kiln sites due to higher C concentrations and greater depth of the organo-mineral horizon. The C/N ratio in charcoal-enriched soil horizons is significantly higher than in the neighboring reference soils but clearly attenuated compared to pure wood-charcoal fragments. The CEC is higher in the charcoal-enriched soil horizons, not only due to higher C concentrations but also to increased CEC by carbon unit at kiln sites. The high

  20. Charcoal bed operation for optimal organic carbon removal

    SciTech Connect

    Merritt, C.M.; Scala, F.R.

    1995-05-01

    Historically, evaporation, reverse osmosis or charcoal-demineralizer systems have been used to remove impurities in liquid radwaste processing systems. At Nine Mile point, we recently replaced our evaporators with charcoal-demineralizer systems to purify floor drain water. A comparison of the evaporator to the charcoal-demineralizer system has shown that the charcoal-demineralizer system is more effective in organic carbon removal. We also show the performance data of the Granulated Activated Charcoal (GAC) vessel as a mechanical filter. Actual data showing that frequent backflushing and controlled flow rates through the GAC vessel dramatically increases Total Organic Carbon (TOC) removal efficiency. GAC vessel dramatically increases Total Organic Carbon (TOC) removal efficiency. Recommendations are provided for operating the GAC vessel to ensure optimal performance.

  1. RECYCLE AND REUSE OF CHARCOAL MADE FROM EXCESS SLUDGE IN MEMBRANE BIOREACTOR

    NASA Astrophysics Data System (ADS)

    Tran, Tuyet Thi; Shafiquzzaman, Md.; Nakajima, Jun

    Charcoal produced from excess sludge appeared to be useful for removing SMP (soluble microbial products) in MBR (membrane bioreactors) and therefore for reducing membrane fouling. Batch experiments and long-term MBR experiments were performed by using charcoal made of actual excess sludge. In the batch experiments, SMP was removed effectively through charcoal addition. This approach proved especially effective for the removal of carbohydrate. Charcoal would serve as an absorbent and coagulant in SMP removal. High BOD (biochemical oxygen demand) removal efficiencies produced no negative effects on biological activity in the reactors during the long-term MBR experiments involving charcoal addition. The decrease of humic substances and COD (chemical oxygen demand) through charcoal addition suggested that this approach effectively enhanced the performance of activated sludge treatment. A charcoal addition of more than 0.1% in long-term MBR experiments effectively decreased the membrane fouling frequency. The use of charcoal therefore served to mitigate membrane fouling. A decrease in carbohydrate, corresponding to the increase in the mean fouling period, suggested that a charcoal addition of more than 0.1% effectively removed SMP, especially carbohydrate. A charcoal cyclic reuse system is also proposed. This system would involve charcoal production and charcoal addition to MBR.

  2. Influence of charcoal burning induced pyrolysis on soils

    NASA Astrophysics Data System (ADS)

    Hirsch, Florian; Nicolay, Alexander; Pötzsch, Bastian; Fritzsche, Marie; Raab, Alexandra; Raab, Thomas

    2014-05-01

    In Lusatia, Northeastern Germany, the production of ironware between the 16th and 19th century left behind a remarkable amount of charcoal kilns in the forests north of Cottbus. Remote sensing surveys, underpinned by archaeological studies, show that charcoal was gained around Cottbus from several thousand charcoal kilns which had internal diameters up to 20 m. For the study site with 35 km2 area, the until now prospected total ground area below the charcoal kilns which was potentially affected by the pyrolysis is about 0,5 km2. Historic data indicates that the pyrolysis in the charcoal kiln took up to several weeks, for the kilns with a diameter of 20 m about 20 days. To characterize the depth of thermal alteration of soils below the kiln our current focus is on the differentiation of the iron hydroxides by small-scale vertical analysis of soil profiles. The study site is situated 16 km northeast of Cottbus at the opencast mine Jänschwalde. Field work was done during the archaeological rescue excavation of a charcoal kiln in a 50 m long trench crossing an about 15 m wide charcoal kiln. One vertical profile outside the charcoal kiln and two vertical profiles below the charcoal kiln were chosen for analysis. The magnetic susceptibility was measured in situ on the undisturbed profile and ex situ on stepwise heated samples (105, 350, 550, 750 and 950°C). The total iron content was quantified ex situ by x-ray fluorescence. Our first results indicate a change in the magnetic susceptibility in the contact area of the mineral soil and the charcoal kiln. The influence of the pyrolysis on the soil is restricted to areas where the soil was not shielded against the heat by ash or organic material.

  3. Soil Charcoal to Assess the Impacts of Past Human Disturbances on Tropical Forests

    PubMed Central

    Vleminckx, Jason; Morin-Rivat, Julie; Biwolé, Achille B.; Daïnou, Kasso; Gillet, Jean-François; Doucet, Jean-Louis; Drouet, Thomas; Hardy, Olivier J.

    2014-01-01

    The canopy of many central African forests is dominated by light-demanding tree species that do not regenerate well under themselves. The prevalence of these species might result from ancient slash-and-burn agricultural activities that created large openings, while a decline of these activities since the colonial period could explain their deficit of regeneration. To verify this hypothesis, we compared soil charcoal abundance, used as a proxy for past slash-and-burn agriculture, and tree species composition assessed on 208 rainforest 0.2 ha plots located in three areas from Southern Cameroon. Species were classified in regeneration guilds (pioneer, non-pioneer light-demanding, shade-bearer) and characterized by their wood-specific gravity, assumed to reflect light requirement. We tested the correlation between soil charcoal abundance and: (i) the relative abundance of each guild, (ii) each species and family abundance and (iii) mean wood-specific gravity. Charcoal was found in 83% of the plots, indicating frequent past forest fires. Radiocarbon dating revealed two periods of fires: “recent” charcoal were on average 300 years old (up to 860 BP, n = 16) and occurred in the uppermost 20 cm soil layer, while “ancient” charcoal were on average 1900 years old (range: 1500 to 2800 BP, n = 43, excluding one sample dated 9400 BP), and found in all soil layers. While we expected a positive correlation between the relative abundance of light-demanding species and charcoal abundance in the upper soil layer, overall there was no evidence that the current heterogeneity in tree species composition can be explained by charcoal abundance in any soil layer. The absence of signal supporting our hypothesis might result from (i) a relatively uniform impact of past slash-and-burn activities, (ii) pedoturbation processes bringing ancient charcoal to the upper soil layer, blurring the signal of centuries-old Human disturbances, or (iii) the prevalence of other

  4. Commercial charcoal manufacture in Brazil

    SciTech Connect

    Rezende, M.E.; Lessa, A.; Pasa, V.; Sampaio, R.; Macedo, P.

    1993-12-31

    Brazil is the only country where charcoal has a major industrial us. Almost 40% of the pig iron and all the ferroalloys produced in the country are based on it and were established near Minas Gerais iron ore deposits using non-sustainable farm charcoal. Since the 1980s charcoal production from large eucalyptus forests is gradually increasing, accounting for 40% of the 8 million tonnes produced in 1991. Farm charcoal is produced when native forests are slashed to give way to farm land. Adequate techniques, labor rights or environmental concerns are not common in this scenario. In large eucalyptus forests charcoal production has a different business approach. Several kinds of masonry ovens are used in both scenarios. Continuous carbonization kilns are not feasible yet because of their high capital cost. The search for a new cheapest design or for the upgrading of the carbonization byproducts is a must. Promising results are shown. Plastics and fine chemicals were already obtained from wood tar. The first Brazilian pilot plant for wood tar fractionation will be started by 9/93. Ironworks have different profiles. Some plants are up-to-date integrated mini-steelworks. Others are small producers of pig ingots. They have in common the need to face coke ironmaking route. Brazilian exports of charcoal based iron and steel products have attained the goal until now. Future charcoal competitiveness will not be so easy. Although expertises believe that coke prices can not stand low for long time it poses additional difficulty to the Brazilian charcoal ironmaker. Three scenarios projected for the future of charcoal ironmaking show that as long as charcoal production costs are properly managed, charcoal will be competitive with coke. The authors defend a common research program that looks for technologies suited to the Brazilian reality.

  5. Formation of charcoal from biomass in a sealed reactor

    SciTech Connect

    Mok, W.S.L.; Antal, M.J. Jr. ); Szabo, P.; Varhegyi, G.; Zelei, B. )

    1992-04-01

    In this paper, samples o cellulose, hemicellulose, lignin, and nine species of whole biomass are pyrolyzed in sealed reactors. Very high charcoal yields (e.g., 40% from cellulose, 48% from Eucalyptus gummifera) were obtained. Higher sample loading (sample mass per unit reactor volume) increased charcoal yield and the associated exothermic heat release and lowered the reaction onset temperature. These effects were induced by the vapor-phase concentrations of the volatile products, and not the system pressure. Addition of water catalyzed the reaction and increased the char yield. These observations suggest that charcoal formation is autocatalyzed by water, an initial pyrolysis product. When whole biomass was used as a feedstock, higher charcoal yields were obtained from species with high lignin and/or low hemicellulose content.

  6. Research report: Charcoal type used for hookah smoking influences CO production.

    PubMed

    Medford, Marlon A; Gasier, Heath G; Hexdall, Eric; Moffat, Andrew D; Freiberger, John J; Moon, Richard E

    2015-01-01

    A hookah smoker who was treated for severe carbon monoxide poisoning with hyperbaric oxygen reported using a different type of charcoal prior to hospital admission, i.e., quick-light charcoal. This finding led to a study aimed at determining whether CO production differs between charcoals commonly used for hookah smoking, natural and quick-light. Our hypothesis was that quick-light charcoal produces significantly more CO than natural charcoal. A medium-sized hookah, activated charcoal filter, calibrated syringe, CO gas analyzer and infrared thermometer were assembled in series. A single 9-10 g briquette of either natural or quick-light charcoal was placed atop the hookah bowl and ignited. CO output (ppm) and temperature (degrees C) were measured in three-minute intervals over 90 minutes. The mean CO levels produced by quick-light charcoal over 90 minutes was significantly higher (3728 ± 2028) compared to natural charcoal (1730 ± 501 ppm, p = 0.016). However, the temperature was significantly greater when burning natural charcoal (292 ± 87) compared to quick-light charcoal (247 ± 92 degrees C, p = 0.013). The high levels of CO produced when using quick-light charcoals may be contributing to the increase in reported hospital admissions for severe CO poisoning. PMID:26403022

  7. Decolorization of crude latex by activated charcoal, purification and physico-chemical characterization of religiosin, a milk-clotting serine protease from the latex of Ficus religiosa.

    PubMed

    Kumari, Moni; Sharma, Anurag; Jagannadham, M V

    2010-07-14

    The crude latex of Ficus religiosa is decolorized by activated charcoal. Decolorization follows the Freundlich and Langmuir equations. A serine protease, named religiosin, has been purified to homogeneity from the decolorized latex using anion exchange chromatography. Religiosin is a glycoprotein with a molecular mass of 43.4 kDa by MALDI-TOF. Religiosin is an acidic protein with a pI value of 3.8 and acts optimally at pH 8.0-8.5 and temperature 50 degrees C. The proteolytic activity of religiosin is strongly inhibited by PMSF and chymostatin indicating that the enzyme is a serine protease. The extinction coefficient (epsilon(1%)(280)) of religiosin is 29.47 M(-1) cm(-1)with 16 tryptophan, 26 tyrosine, and 11 cysteine residues per molecule. The enzyme shows broad substrate specificity against natural as well as synthetic substrates with an apparent K(m) of 0.066 mM and 6.25 mM using casein and Leu-pNA, respectively. MS/MS analysis confirms the novelty of the enzyme. Religiosin is highly stable against denaturants, metal ions, and detergents as well as over a wide range of pH and temperature. In addition, the enzyme exhibits milk-clotting as well as detergent activity. PMID:20560603

  8. Fire history reconstruction in grassland ecosystems: amount of charcoal reflects local area burned

    NASA Astrophysics Data System (ADS)

    Leys, Bérangère; Brewer, Simon C.; McConaghy, Scott; Mueller, Joshua; McLauchlan, Kendra K.

    2015-11-01

    Fire is one of the most prevalent disturbances in the Earth system, and its past characteristics can be reconstructed using charcoal particles preserved in depositional environments. Although researchers know that fires produce charcoal particles, interpretation of the quantity or composition of charcoal particles in terms of fire source remains poorly understood. In this study, we used a unique four-year dataset of charcoal deposited in traps from a native tallgrass prairie in mid-North America to test which environmental factors were linked to charcoal measurements on three spatial scales. We investigated small and large charcoal particles commonly used as a proxy of fire activity at different spatial scales, and charcoal morphotypes representing different types of fuel. We found that small (125-250 μm) and large (250 μm-1 mm) particles of charcoal are well-correlated (Spearman correlation = 0.88) and likely reflect the same spatial scale of fire activity in a system with both herbaceous and woody fuels. There was no significant relationship between charcoal pieces and fire parameters <500 m from the traps. Moreover, local area burned (<5 km distance radius from traps) explained the total charcoal amount, and regional burning (200 km radius distance from traps) explained the ratio of non arboreal to total charcoal (NA/T ratio). Charcoal variables, including total charcoal count and NA/T ratio, did not correlate with other fire parameters, vegetation cover, landscape, or climate variables. Thus, in long-term studies that involve fire history reconstructions, total charcoal particles, even of a small size (125-250 μm), could be an indicator of local area burned. Further studies may determine relationships among amount of charcoal recorded, fire intensity, vegetation cover, and climatic parameters.

  9. Cr(VI) removal from synthetic wastewater using coconut shell charcoal and commercial activated carbon modified with oxidizing agents and/or chitosan.

    PubMed

    Babel, Sandhya; Kurniawan, Tonni Agustiono

    2004-02-01

    In this study, the technical feasibility of coconut shell charcoal (CSC) and commercial activated carbon (CAC) for Cr(VI) removal is investigated in batch studies using synthetic electroplating wastewater. Both granular adsorbents are made up of coconut shell (Cocos nucifera L.), an agricultural waste from local coconut industries. Surface modifications of CSC and CAC with chitosan and/or oxidizing agents, such as sulfuric acid and nitric acid, respectively, are also conducted to improve removal performance. The results of their Cr removal performances are statistically compared. It is evident that adsorbents chemically modified with an oxidizing agent demonstrate better Cr(VI) removal capabilities than as-received adsorbents in terms of adsorption rate. Both CSC and CAC, which have been oxidized with nitric acid, have higher Cr adsorption capacities (CSC: 10.88, CAC: 15.47 mg g(-1)) than those oxidized with sulfuric acid (CSC: 4.05, CAC: 8.94 mg g(-1)) and non-treated CSC coated with chitosan (CSCCC: 3.65 mg g(-1)), respectively, suggesting that surface modification of a carbon adsorbent with a strong oxidizing agent generates more adsorption sites on their solid surface for metal adsorption. PMID:14637353

  10. Recovery of datable charcoal beneath young lavas: lessons from Hawaii.

    USGS Publications Warehouse

    Lockwood, J.P.; Lipman, P.W.

    1980-01-01

    Field studies in Hawaii aimed at providing a radiocarbon-based chronology of prehistoric eruptive activity have led to a good understanding of the processes that govern the formation and preservation of charcoal beneath basaltic lava flows. Charcoal formation is a rate-dependent process controlled primarily by temperature and duration of heating, as well as by moisture content, density, and size of original woody material. Charcoal will form wherever wood buried by lava is raised to sufficiently high temperatures, but owing to the availability of oxygen it is commonly burned to ash soon after formation. Wherever oxygen circulation is sufficiently restricted, charcoal will be preserved, but where atmospheric oxygen circulates freely, charcoal will only be preserved at a lower temperature, below that required for charcoal ignition or catalytic oxidation. These factors cause carbonized wood, especially that derived from living roots, to be commonly preserved beneath all parts of pahoehoe flows (where oxygen circulation is restricted), but only under margins of aa. Practical guidelines are given for the recovery of datable charcoal beneath pahoehoe and aa. Although based on Hawaiian basaltic flows, the guidelines should be applicable to other areas. -Authors

  11. Ancient charcoal as a natural archive for paleofire regime and vegetation change in the Mayumbe, Democratic Republic of the Congo

    NASA Astrophysics Data System (ADS)

    Hubau, Wannes; Van den Bulcke, Jan; Kitin, Peter; Mees, Florias; Baert, Geert; Verschuren, Dirk; Nsenga, Laurent; Van Acker, Joris; Beeckman, Hans

    2013-09-01

    Charcoal was sampled in four soil profiles at the Mayumbe forest boundary (DRC). Five fire events were recorded and 44 charcoal types were identified. One stratified profile yielded charcoal assemblages around 530 cal yr BP and > 43.5 cal ka BP in age. The oldest assemblage precedes the period of recorded anthropogenic burning, illustrating occasional long-term absence of fire but also natural wildfire occurrences within tropical rainforest. No other charcoal assemblages older than 2500 cal yr BP were recorded, perhaps due to bioturbation and colluvial reworking. The recorded paleofires were possibly associated with short-lived climate anomalies. Progressively dry climatic conditions since ca. 4000 cal yr BP onward did not promote paleofire occurrence until increasing seasonality affected vegetation at the end of the third millennium BP, as illustrated by a fire occurring in mature rainforest that persisted until around 2050 cal yr BP. During a drought episode coinciding with the 'Medieval Climate Anomaly', mature rainforest was locally replaced by woodland savanna. Charcoal remains from pioneer forest indicate that fire hampered forest regeneration after climatic drought episodes. The presence of pottery shards and oil-palm endocarps associated with two relatively recent paleofires suggests that the effects of climate variability were amplified by human activities.

  12. Facile xenon capture and release at room temperature using a metal-organic framework: a comparison with activated charcoal

    SciTech Connect

    Thallapally, Praveen K.; Grate, Jay W.; Motkuri, Radha K.

    2012-01-11

    Two well known Metal organic frameworks (MOF-5, NiDOBDC) were synthesized and studied for facile xenon capture and separation. Our results indicate the NiDOBDC adsorbs significantly more xenon than MOF-5, releases it more readily than activated carbon, and is more selective for Xe over Kr than activated carbon.

  13. Activated charcoal-mediated RNA extraction method for Azadirachta indica and plants highly rich in polyphenolics, polysaccharides and other complex secondary compounds

    PubMed Central

    2013-01-01

    Background High quality RNA is a primary requisite for numerous molecular biological applications but is difficult to isolate from several plants rich in polysaccharides, polyphenolics and other secondary metabolites. These compounds either bind with nucleic acids or often co-precipitate at the final step and many times cannot be removed by conventional methods and kits. Addition of vinyl-pyrollidone polymers in extraction buffer efficiently removes polyphenolics to some extent, but, it failed in case of Azadirachta indica and several other medicinal and aromatic plants. Findings Here we report the use of adsorption property of activated charcoal (0.03%–0.1%) in RNA isolation procedures to remove complex secondary metabolites and polyphenolics to yield good quality RNA from Azadirachta indica. We tested and validated our modified RNA isolation method across 21 different plants including Andrographis paniculata, Aloe vera, Rosa damascena, Pelargonium graveolens, Phyllanthus amarus etc. from 13 other different families, many of which are considered as tough system for isolating RNA. The A260/280 ratio of the extracted RNA ranged between 1.8-2.0 and distinct 28S and 18S ribosomal RNA bands were observed in denaturing agarose gel electrophoresis. Analysis using Agilent 2100 Bioanalyzer revealed intact total RNA yield with very good RNA Integrity Number. Conclusions The RNA isolated by our modified method was found to be of high quality and amenable for sensitive downstream molecular applications like subtractive library construction and RT-PCR. This modified RNA isolation procedure would aid and accelerate the biotechnological studies in complex medicinal and aromatic plants which are extremely rich in secondary metabolic compounds. PMID:23537338

  14. Chemical analysis and potential health risks of hookah charcoal.

    PubMed

    Elsayed, Yehya; Dalibalta, Sarah; Abu-Farha, Nedal

    2016-11-01

    Hookah (waterpipe) smoking is a very common practice that has spread globally. There is growing evidence on the hazardous consequences of smoking hookah, with studies indicating that its harmful effects are comparable to cigarette smoking if not worse. Charcoal is commonly used as a heating source for hookah smoke. Although charcoal briquettes are thought to be one of the major contributors to toxicity, their composition and impact on the smoke generated remains largely unidentified. This study aims to analyze the elemental composition of five different raw synthetic and natural charcoals by using Carbon-Hydrogen-Nitrogen (CHN) analysis, inductively coupled plasma (ICP), and scanning electron microscopy coupled with energy dispersive X-Ray spectrometry (SEM-EDS). Elemental analysis showed that the raw charcoals contain heavy metals such as zinc, iron, cadmium, vanadium, aluminum, lead, chromium, manganese and cobalt at concentrations similar, if not higher than, cigarettes. In addition, thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) was used to analyze the chemical composition of the smoke produced from burning the charcoal samples. The smoke emitted from charcoal was found to be the source of numerous compounds which could be hazardous to health. A total of seven carcinogens, 39 central nervous system depressants and 31 respiratory irritants were identified. PMID:27343945

  15. [Hygienic study of an activated fibrous charcoal material as a sorbing filtering element for drinking water afterpurification].

    PubMed

    Prokopov, V A; Mironets, N V; Gakal, R K; Maktaz, E D; Dugan, A M; Teteneva, I A; Tarabarova, S B; Martyshchenko, N V; Nadvornaia, Zh D

    1993-01-01

    The results of complex toxicological and hygienic study showed that the quality of pipe water filtered through the activated carbonic fibrous material (ACFM) "Dnepr-F" forming a part of absorptive filtering element improved markedly. The content of organic substances decreased drastically as well as that of nitrates and iron. Microbiological indices did not suffer appreciable changes and were within permissible limits. The water filtered through the absorptive element with ACFM had no adverse influence on the organisms of warm-blooded animals. Proceeding from foregoing one can conclude that the "Dnepr-F" may be recommended as a part of absorptive filtering element for the final refinement of drinking water. PMID:8209499

  16. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR USE OF A PASSIVE SAMPLING DEVISE FOR THE COLLECTION OF AIRBORNE VOCS AT FIXED INDOOR AND OUTDOOR SITES (UA-F-12.0)

    EPA Science Inventory

    The purpose of this SOP is to describe the methods used to sample residential indoor and outdoor atmospheres for the presence of certain volatile organic compounds (VOCs) by means of absorption onto activated charcoal contained within a sampling badge. Activated charcoal diffusi...

  17. U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--STANDARD OPERATING PROCEDURE FOR USE OF A PASSIVE SAMPLING DEVICE FOR THE COLLECTION OF AIRBORNE VOCS AT FIXED INDOOR AND OUTDOOR SITES (UA-F-12.1)

    EPA Science Inventory

    The purpose of this SOP is to describe the methods used to sample residential indoor and outdoor atmospheres for the presence of certain volatile organic compounds (VOCs) by means of absorption onto activated charcoal contained within a sampling badge. Activated charcoal diffusi...

  18. BBQ charcoal as an important source of mercury emission.

    PubMed

    Pandey, Sudhir Kumar; Kim, Ki-Hyun; Kang, Chang-Hee; Jung, Myung Chae; Yoon, H

    2009-02-15

    In this study, the environmental significance of mercury emission has been investigated with respect to the use of the barbecue (BBQ) charcoal. For this purpose, emission gas samples collected from a total of 11 barbecue charcoal products commonly available in the Korean market were analyzed. All of these products consist of both domestic (4 types) and imported products (7 types from three countries). The emission concentration of Hg varied widely from sample to sample ranging from 114 to 496ngm(-3). The amount of Hg emission appeared to be affected by the diverse nature of raw materials and/or the processes involved in their production. In light of the recent reference exposure limits (REL) of Hg, it can be a potential threat to human health. As such, a proper regulation is desirable from a toxicological viewpoint to reduce the potential risk associated with the use of BBQ charcoal. PMID:18571317

  19. Oral Activated Charcoal Prevents Experimental Cerebral Malaria in Mice and in a Randomized Controlled Clinical Trial in Man Did Not Interfere with the Pharmacokinetics of Parenteral Artesunate

    PubMed Central

    Alexander, Neal D.; Aziz, Naveed; Owens, Benjamin M. J.; Kaur, Harparkash; Jasseh, Momodou; Muangnoicharoen, Sant; Sumariwalla, Percy F.; Warhurst, David C.; Ward, Stephen A.; Conway, David J.; Ulloa, Luis; Tracey, Kevin J.; Foxwell, Brian M. J.; Kaye, Paul M.; Walther, Michael

    2010-01-01

    Background Safe, cheap and effective adjunct therapies preventing the development of, or reducing the mortality from, severe malaria could have considerable and rapid public health impact. Oral activated charcoal (oAC) is a safe and well tolerated treatment for acute poisoning, more recently shown to have significant immunomodulatory effects in man. In preparation for possible efficacy trials in human malaria, we sought to determine whether oAC would i) reduce mortality due to experimental cerebral malaria (ECM) in mice, ii) modulate immune and inflammatory responses associated with ECM, and iii) affect the pharmacokinetics of parenteral artesunate in human volunteers. Methods/Principal Findings We found that oAC provided significant protection against P. berghei ANKA-induced ECM, increasing overall survival time compared to untreated mice (p<0.0001; hazard ratio 16.4; 95% CI 6.73 to 40.1). Protection from ECM by oAC was associated with reduced numbers of splenic TNF+ CD4+ T cells and multifunctional IFNγ+TNF+ CD4+ and CD8+ T cells. Furthermore, we identified a whole blood gene expression signature (68 genes) associated with protection from ECM. To evaluate whether oAC might affect current best available anti-malarial treatment, we conducted a randomized controlled open label trial in 52 human volunteers (ISRCTN NR. 64793756), administering artesunate (AS) in the presence or absence of oAC. We demonstrated that co-administration of oAC was safe and well-tolerated. In the 26 subjects further analyzed, we found no interference with the pharmacokinetics of parenteral AS or its pharmacologically active metabolite dihydroartemisinin. Conclusions/Significance oAC protects against ECM in mice, and does not interfere with the pharmacokinetics of parenteral artesunate. If future studies succeed in establishing the efficacy of oAC in human malaria, then the characteristics of being inexpensive, well-tolerated at high doses and requiring no sophisticated storage would make o

  20. Predicting distributions of charcoal in Amazonian soils: approaches from earth and space

    NASA Astrophysics Data System (ADS)

    McMichael, C.; Palace, M. W.; Bush, M. B.; Braswell, R.; Hagen, S. C.; Czarnecki, C.; Neves, E.; Raczka, M.

    2011-12-01

    The direct linkage between fire and human activity in Amazonian rainforests is evidenced in both remote sensing datasets and field-based research. Paleoecological and archaeological data suggest the synergy has persisted millennia, and that human populations may have equaled modern numbers before European contact. Pre-Columbian people used fire to clear forests, but also combined charcoal with other materials to form Amazonian Black Earths (ABE), a nutrient rich anthrosol believed to be capable of sustaining large-scale permanent societies in such nutrient-poor tropical settings. The majority of impacted sites are found on bluffs overlooking Amazonian rivers, which are considered 'preferred' settings. Here, we examine predictions about preferred settings and the distributions of charcoal resulting from pre-Columbian human activity in western and central Amazonia using proxies from both earth and space. Soil sampling, stratified based on distance from river and forest seasonality, was used to determine whether preferred locations had higher probabilities of impacts. We analyzed more than 351 soil cores for ABE and macroscopic charcoal (> 500 μm) in the upper 20 cm of soil (representing modern fires), and in soils > 20 cm depth (representing historic fires). ABE was absent from all sites, but logistic regressions indicated that probabilities of finding soil charcoal significantly decreased as distance from river increased in aseasonal forests. However, in more seasonal forests, the probability of finding charcoal was increased, although distance from river was not a significant factor. Alternately, the location of ABE and charcoal mainly along major rivers may be an artifact of sampling. To look at distributions of ABE across broad spatial scales that may not be accessible from the ground, we used Hyperion satellite images to detect canopy chemistry differences resulting from various soil nutrients (i.e. soil enrichment occurring at ABE sites). Our initial findings

  1. Removal of NOx or its conversion into harmless gases by charcoals and composites of metal oxides

    SciTech Connect

    Ishihara, Shigehisa; Furutsuka, Takeshi

    1996-12-31

    In recent years, much attention has been devoted to environmental problems such as acid rain, photochemical smog and water pollution. In particular, NOx emissions from factories, auto mobiles, etc. in urban areas have become worse. To solve these problems on environmental pollution on a global scale, the use of activated charcoal to reduce air pollutants is increasing. However, the capability of wood-based charcoal materials is not yet fully known. The removal of NOx or its conversion into harmless gases such as N{sub 2} should be described. In this study, the adsorption of NO over wood charcoal or metal oxide-dispersed wood charcoal was investigated. In particular, carbonized wood powder of Sugi (Cryptomeria japonica D. Don) was used to study the effectivity of using these materials in adsorbing NOx. Since wood charcoal is chemically stable, metal oxide with the ability of photocatalysis was dispersed into wood charcoal to improve its adsorption and capability to use the light energy effectively.

  2. Effects of quebracho tannin extract (Schinopsis balansae Engl.) and activated charcoal on nitrogen balance, rumen microbial protein synthesis and faecal composition of growing Boer goats.

    PubMed

    Al-Kindi, Amal; Dickhoefer, Uta; Schlecht, Eva; Sundrum, Albert; Schiborra, Anne

    2016-08-01

    Under irrigated arid conditions, organic fertiliser rich in slowly decomposable nitrogen (N) and carbon (C) is needed for soil fertility maintenance. Feeding ruminants with condensed tannins will lower ruminal protein degradation, reduce urinary N excretion and might increase the faecal fraction of slowly decomposable N. Supplementation with activated charcoal (AC) might enrich manure with slowly degrading C. Therefore, we investigated the effects of feeding quebracho tannin extract (QTE) and AC on the N balance of goats, the efficiency of microbial protein synthesis in the rumen (EMPS) and the composition of faeces. The feeding trial comprised three periods; in each period, 12 male Boer goats (28 ± 3.9 kg live weight) were assigned to six treatments: a Control diet (per kg diet 500 g grass hay and 500 g concentrate) and to further five treatments the Control diet was supplemented with QTE (20 g and 40 g/kg; diets QTE2 and QTE4, respectively), with AC (15 g and 30 g/kg, diets AC1.5 and AC3.0, respectively) and a mixture of QTE (20 g/kg) plus AC (15 g/kg) (diet QTEAC). In addition to the N balance, EMPS was calculated from daily excretions of purine derivatives, and the composition of faecal N was determined. There was no effect of QTE and AC supplementation on the intake of organic matter (OM), N and fibre, but apparent total tract digestibility of OM was reduced (p = 0.035). Feeding QTE induced a shift in N excretion from urine to faeces (p ≤ 0.001) without altering N retention. Total N excretion tended to decrease with QTE treatments (p = 0.053), but EMPS was not different between treatments. Faecal C excretion was higher in QTE and AC treatments (p = 0.001) compared with the Control, while the composition of faecal N differed only in concentration of undigested dietary N (p = 0.001). The results demonstrate that QTE can be included into diets of goats up to 40 g/kg, without affecting N utilisation, but simultaneously increasing the

  3. Development of charcoal sorbents for helium cryopumping

    SciTech Connect

    Sedgley, D.W.; Tobin, A.G.

    1984-01-01

    Testing of the cryogenically cooled charcoal using fusion-compatible binders for pumping helium has shown promising results. The program demonstrated comparable or improved performance with these binders compared to the charcoal (type and size) using an epoxy binder.

  4. DISEASES OF SOYBEAN: CHARCOAL ROT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean yield losses due to charcoal rot occur regularly. Yield losses of 20-30% due to root and stem infections of soybean caused by the soil-inhabiting fungus Macrophomina phaseolina have been reported in some fields in years highly favorable for disease development. This bulletin summarizes the...

  5. Charcoal production in the Mopane woodlands of Mozambique: what are the trade-offs with other ecosystem services?

    PubMed

    Woollen, Emily; Ryan, Casey M; Baumert, Sophia; Vollmer, Frank; Grundy, Isla; Fisher, Janet; Fernando, Jone; Luz, Ana; Ribeiro, Natasha; Lisboa, Sá N

    2016-09-19

    African woodlands form a major part of the tropical grassy biome and support the livelihoods of millions of rural and urban people. Charcoal production in particular is a major economic activity, but its impact on other ecosystem services is little studied. To address this, our study collected biophysical and social datasets, which were combined in ecological production functions, to assess ecosystem service provision and its change under different charcoal production scenarios in Gaza Province, southern Mozambique. We found that villages with longer histories of charcoal production had experienced declines in wood suitable for charcoal, firewood and construction, and tended to have lower perceived availabilities of these services. Scenarios of future charcoal impacts indicated that firewood and woody construction services were likely to trade-off with charcoal production. However, even under the most extreme charcoal scenario, these services were not completely lost. Other provisioning services, such as wild food, medicinal plants and grass, were largely unaffected by charcoal production. To reduce the future impacts of charcoal production, producers must avoid increased intensification of charcoal extraction by avoiding the expansion of species and sizes of trees used for charcoal production. This is a major challenge to land managers and policymakers in the area.This article is part of the themed issue 'Tropical grassy biomes: linking ecology, human use and conservation'. PMID:27502380

  6. An Active Tutorial on Distance Sampling

    ERIC Educational Resources Information Center

    Richardson, Alice

    2007-01-01

    The technique of distance sampling is widely used to monitor biological populations. This paper documents an in-class activity to introduce students to the concepts and the mechanics of distance sampling in a simple situation that is relevant to their own experiences. Preparation details are described. Variations and extensions to the activity are…

  7. Effect of charcoal amendment on adsorption, leaching and degradation of isoproturon in soils

    NASA Astrophysics Data System (ADS)

    Si, Youbin; Wang, Midao; Tian, Chao; Zhou, Jing; Zhou, Dongmei

    2011-04-01

    The effects of charcoal amendment on adsorption, leaching and degradation of the herbicide isoproturon in soils were studied under laboratory conditions. The adsorption data all fitted well with the Freundlich empirical equation. It was found that the adsorption of isoproturon in soils increased with the rate of charcoal amended (correlation coefficient r = 0.957 **, P < 0.01). The amount of isoproturon in leachate decreased with the increase of the amount of charcoal addition to soil column, while the retention of isoproturon in soils increased with an increase in the charcoal content of soil samples. Biodegradation was still the most significant mechanism for isoproturon dissipation from soil. Charcoal amendment greatly reduced the biodegradation of isoproturon in soils. The half-lives of isoproturon degradation ( DT50) in soils greatly extended when the rate of added charcoal inceased from 0 to 50 g kg - 1 (for Paddy soil, DT50 values increased from 54.6 to 71.4 days; for Alfisol, DT50 from 16.0 to 136 days; and for Vertisol, DT50 from 15.2 to 107 days). The degradation rate of isoproturon in soils was significantly negatively correlated with the amount of added charcoal. This research suggests that charcoal amendment may be an effective management practice for reducing pesticide leaching and enhancing its persistence in soils.

  8. Charcoal as evidence of fire regimes in the Pleistocene of the California Islands

    NASA Astrophysics Data System (ADS)

    Scott, A. C.; Hardiman, M.; Pinter, N.; Anderson, R. S.

    2012-04-01

    Charcoal has been recovered from a range of late Pleistocene sites both in Santa Cruz Island and Santa Rosa Island, belonging to the California Channel Islands. Sediments have been dated using radiocarbon measurements based on wood charcoal, fungal sclerotia, glassy carbon and fecal pellets and are given as calendar years bp. Charcoal assemblages from samples dating from 24,694 to 12,900 years are dominated by coniferous wood charcoal. Little angiosperm charcoal was recovered in any of the samples. Fungal sclerotia are frequent in a number of samples from a range of ages both on Santa Cruz and Santa Rosa. Fecal pellets are common in most samples and abundant in others. Some of the fecal pellets have hexagonal sides and are likely to represent termite frass. The sediments are fluvial in origin and the distribution of charcoal is irregular. The charcoal records a significant record of fire before the earliest documented human arrival on the islands and there is no evidence for a catstrophic fire triggered by a cometary impact at the onset of the younger Dryas, 12,900 cal years bp.

  9. Can Charcoal Provide Information About Fire Effects and Fire Severity?

    NASA Astrophysics Data System (ADS)

    Belcher, Claire; Hudpsith, Victoria; Doerr, Stefan; Santin, Cristina

    2016-04-01

    Building an understanding of the impact of a wildfire is critical to the management of ecosystems. Aspects of fire severity such as the amount of soil heating, can relate to post-fire ecosystem recovery. Yet, there is no quantitative measure of this in current post-burn fire severity assessments, which are mostly qualitative ground-based visual assessments of organic matter loss, and as such can be subjective and variable between ecosystems. In order to develop a unifying fire severity assessment we explore the use of charcoal produced during a wildfire, as a tool. Charcoal has been suggested to retain some information about the nature of the fire in which it was created and one such physical property of charcoal that can be measured post-fire is its ability to reflect light when studied under oil using reflectance microscopy. The amount of light reflected varies between charcoals and is thought to be explained by the differential ordering of graphite-like phases within the char however, to what aspects of a fire's nature this alteration pertains is unknown. We have explored the formation of charcoal reflectance in 1) laboratory-based experiments using an iCone calorimeter and in 2) experimental forest scale and natural wildland fires occurring in Canada in spring 2015. In our laboratory experiments we assessed the formation and evolution of charcoal reflectance during pre-ignition heating, peak fire intensity through to the end of flaming and the transition to oxidative/smoldering heating regimes. In the prescribed and natural wildland fires we positioned the same woods used in our laboratory experiments, rigged with thermocouples in the path of oncoming fires in order to assess the resulting charcoal reflectance in response to the heating regime imposed by the fire on the samples. In this presentation we will outline our approach, findings and discuss the potential for charcoal reflectance to provide a tool in post-fire assessments seeking to determine levels of

  10. Commercial charcoal production in the Ibarapa district of southwestern Nigeria: forestry dividends and welfare implications.

    PubMed

    Salami, Kabiru K; Brieger, William R

    2010-01-01

    Logging activities have long provided both wood fuel and charcoal for household and commercial use in rural and urban communities in developing countries. However, logging problems range from deforestation to threatened household air quality from burning wood and charcoal. This exploratory case study triangulated 15 in-depth interviews among charcoal bulk buyers and the workers, observations of workers at two èédú (charcoal) commercial depots in Igbo-Ora and of workers in the forest, and review of studies in academic database. Three categories of people are working in the business ranging from the producers in the forests (alaake) to the bulk buyers (olowo) in the middle and the wholesalers (ajagunta) in the city. A small team of 4-8 people can produce three pickup truck loads of charcoal in 2 weeks, and a large team between 7-8 loads. The olowo and the alaake have associations, membership cards, and meet to discuss business progress and regulate members' economic behavior. Close to 35,000 bags of charcoal of 450 pickup trucks may make the journey weekly from Ibarapa. Overall, the charcoal business is informal, and the local people also frown at cutting any useful indigenous trees ascertaining that an individual's actions may affect the whole community. The role of community health educators is important in the dissemination of effects of deforestation through charcoal production. PMID:22192943

  11. Effects of Carbonization Parameters of Moso-Bamboo-Based Porous Charcoal on Capturing Carbon Dioxide

    PubMed Central

    Jhan, Jhih-Wei; Cheng, Yi-Ming; Cheng, Hau-Hsein

    2014-01-01

    This study experimentally analyzed the carbon dioxide adsorption capacity of Moso-bamboo- (Phyllostachys edulis-) based porous charcoal. The porous charcoal was prepared at various carbonization temperatures and ground into powders with 60, 100, and 170 meshes, respectively. In order to understand the adsorption characteristics of porous charcoal, its fundamental properties, namely, charcoal yield, ash content, pH value, Brunauer-Emmett-Teller (BET) surface area, iodine number, pore volume, and powder size, were analyzed. The results show that when the carbonization temperature was increased, the charcoal yield decreased and the pH value increased. Moreover, the bamboo carbonized at a temperature of 1000°C for 2 h had the highest iodine sorption value and BET surface area. In the experiments, charcoal powders prepared at various carbonization temperatures were used to adsorb 1.854% CO2 for 120 h. The results show that the bamboo charcoal carbonized at 1000°C and ground with a 170 mesh had the best adsorption capacity, significantly decreasing the CO2 concentration to 0.836%. At room temperature and atmospheric pressure, the Moso-bamboo-based porous charcoal exhibited much better CO2 adsorption capacity compared to that of commercially available 350-mesh activated carbon. PMID:25225639

  12. Time-dependent response of a charcoal bed to radon and water vapor in flowing air

    SciTech Connect

    Henkel, J.A.; Fentiman, A.W.; Blue, T.E.

    1995-12-31

    Extremely high airborne concentrations of radon gas may be encountered during the remediation of uranium mill tailings storage facilities. Radon is also a constituent of the off-gas of mill-tailing vitrification. An effective way to remove radon from either gas is to pass the gas through a packed bed containing activated charcoal. Measurements of radon concentrations in the environment using charcoal canisters were first described by George. Canisters similar to those used by George in his first experiments have become the U.S. Environmental Protection Agency`s (EPA`s) standard for measuring environmental radon and were described in the EPA protocol for environmental radon measurement. The dynamic behavior of EPA charcoal canisters has been previously described with a mathematical model for the kinetics of radon gas adsorption in air in the presence of water vapor. This model for charcoal canisters has been extended to large charcoal beds with flowing air containing radon and water vapor. The mathematical model for large charcoal beds can be used to evaluate proposed bed designs or to model existing beds. Parameters that affect the radon distribution within a charcoal bed that can be studied using the mathematical model include carrier gas relative humidity and flow velocity, and input radon concentration. In addition, the relative performances of several different charcoals can be studied, provided sufficient information about their adsorption, desorption, and diffusion constants is known.

  13. Charcoal kiln relicts - a favorable site for tree growth?

    NASA Astrophysics Data System (ADS)

    Buras, Allan; Hirsch, Florian; van der Maaten, Ernst; Takla, Melanie; Räbiger, Christin; Cruz Garcia, Roberto; Schneider, Anna; Raab, Alexandra; Raab, Thomas; Wilmking, Martin

    2015-04-01

    the German lowlands (e.g. Raab et al., 2015) and their potentially adverse effects on tree growth, these findings elucidate a yet unknown impact of past human activities on recent biological processes. Glaser, B., Haumaier, L., Guggenberger, G., and Zech, W., 2001: The 'Terra Preta' phenomenon: a model for sustainable agriculture in the humid tropics. Naturwissenschaften, 88, 37-41. Raab, A., Takla, M., Raab, T., Nicolay, A., Schneider, A., Rösler, H., Heußner, K.U., Bönisch, E., 2015. Pre-industrial charcoal production in Lower Lusatia (Brandenburg, Germany): Detection and evaluation of a large charcoal-burning field by combining archaeological studies, GIS-based analyses of shaded-relief maps and dendrochronological age determination. Quaternary International, doi: 10.1016/j.quaint.2014.09.041.

  14. Charcoal/Nitrogen Adsorption Cryocooler

    NASA Technical Reports Server (NTRS)

    Bard, Steven

    1987-01-01

    Refrigerator with no wear-related moving parts produces 0.5 W of cooling at 118 K. When fully developed, refrigerator needs no electrical power, and life expectancy of more than 10 yr, operates unattended to cool sensitive infrared detectors for long periods. Only moving parts in adsorption cryocooler are check valves. As charcoal is cooled in canister, gas pressure drops, allowing inlet check valve to open and admit more nitrogen. When canister is heated, pressure rises, closing inlet valve and eventually opening outlet valve.

  15. Determination of 63Ni and 59Ni in spent ion-exchange resin and activated charcoal from the IEA-R1 nuclear research reactor.

    PubMed

    Taddei, M H T; Macacini, J F; Vicente, R; Marumo, J T; Sakata, S K; Terremoto, L A A

    2013-07-01

    A radiochemical method has been adapted to determine (59)Ni and (63)Ni in samples of radioactive wastes from the water cleanup system of the IEA-R1 nuclear research reactor. The process includes extraction chromatographic resin with dimethylglyoxime (DMG) as a functional group. Activity concentrations of (59)Ni and (63)Ni were measured, respectively, by X-ray spectrometry and liquid scintillation counting, whereas the chemical yield was determined by ICP-OES. The average ratio of measured activity concentrations of (63)Ni and (59)Ni agree well with theory. PMID:23524230

  16. A simple method for vapor dosing of charcoal sorbent tubes.

    PubMed

    Thomas, M L; Cohen, B S

    1995-01-01

    A method for vapor-dosing of charcoal sorbent tubes (CST) that does not require the expense and effort of a test chamber was used to test the desorption efficiency (DE) of seven solvent vapors, representing six classes of solvents as follows: aromatic hydrocarbons (m-xylene); ether/alcohol (2-ethoxyethanol); vinyl monomers (styrene monomer, vinyl acetate); aliphatic hydrocarbons (n-hexane); aliphatic esters (n-butyl acetate); and aliphatic acrylic monomers (methyl methacrylate). The quantities of the solvents used in these experiments would represent eight-hour exposures to concentrations of approximately 0.2 to 10 ppm. The vapor-dosing experimental system consisted of a loaded filter cassette connected directly to a CST. Vapor was generated by injecting liquid solvent onto the glass fiber filter and drawing air through the system. The solvent was desorbed from the filter and charcoal for analysis. Vapor desorption efficiency was determined from the fraction of the injected solvent evaporated from the filter and the amount recovered from the charcoal. The measured DEs were similar to those reported for liquid dosed charcoal. Vapor dosing of sorbent tubes is more representative of samples collected for industrial hygiene exposure assessment. The system is simple to use and applicable for vapor dosing of any sorbent tube. PMID:7872204

  17. Magnificent Ground Water Connection. [Sample Activities].

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC.

    Water conservation and usage is an important concept in science. This document, geared specifically to New England, provides many activities for protecting and discussing ground water situations. Sample activities for grades K-6 include: (1) All the Water in the World; (2) The Case of the Disappearing Water; (3) Deep Subjects--Wells and Ground…

  18. Charcoal from a prehistoric copper mine in the Austrian Alps: dendrochronological and dendrological data, demand for wood and forest utilisation

    PubMed Central

    Pichler, Thomas; Nicolussi, Kurt; Goldenberg, Gert; Hanke, Klaus; Kovács, Kristóf; Thurner, Andrea

    2013-01-01

    During prehistory fire-setting was the most appropriate technique for exploiting ore deposits. Charcoal fragments found in the course of archaeological excavations in a small mine called Mauk E in the area of Schwaz/Brixlegg (Tyrol, Austria) are argued to be evidence for the use of this technology. Dendrochronological analyses of the charcoal samples yielded calendar dates for the mining activities showing that the exploitation of the Mauk E mine lasted approximately one decade in the late 8th century BC. Dendrological studies show that the miners utilised stem wood of spruce and fir from forests with high stand density for fire-setting and that the exploitation of the Mauk E mine had only a limited impact on the local forests. PMID:23565025

  19. Charcoal from a prehistoric copper mine in the Austrian Alps: dendrochronological and dendrological data, demand for wood and forest utilisation.

    PubMed

    Pichler, Thomas; Nicolussi, Kurt; Goldenberg, Gert; Hanke, Klaus; Kovács, Kristóf; Thurner, Andrea

    2013-02-01

    During prehistory fire-setting was the most appropriate technique for exploiting ore deposits. Charcoal fragments found in the course of archaeological excavations in a small mine called Mauk E in the area of Schwaz/Brixlegg (Tyrol, Austria) are argued to be evidence for the use of this technology. Dendrochronological analyses of the charcoal samples yielded calendar dates for the mining activities showing that the exploitation of the Mauk E mine lasted approximately one decade in the late 8th century BC. Dendrological studies show that the miners utilised stem wood of spruce and fir from forests with high stand density for fire-setting and that the exploitation of the Mauk E mine had only a limited impact on the local forests. PMID:23565025

  20. CHARCOAL-PRODUCING INDUSTRIES IN NORTHEASTERN BRAZIL

    EPA Science Inventory

    Charcoal workers in northeastern Brazil: Occupational risks and effects of exposure to wood smoke
    ABSTRACT
    Brazil has the largest production of charcoal in the world, which is used mostly in the iron and steel industries. In most of the production sites, the process is ba...

  1. Development of charcoal sorbents for helium cryopumping

    SciTech Connect

    Sedgley, D.W.; Tobin, A.G.

    1985-09-30

    Improved methods for cryopumping helium were developed for application to fusion reactors where high helium generation rates are expected. This study period evaluated charcoal particle size, bonding agent type and thickness, and substrate thickness. The optimum combination of charcoal, bond, and substrate was used to form a scaled-up panel for evaluation in the Tritium Systems Test Assembly (TSTA) at Los Alamos. The optimum combination is a 12 x 30 mesh coconut charcoal attached to a 0.48 cm thick copper substrate by a 0.015 cm thick silver phosphorus copper braze. A copper cement bond for attaching charcoal to a substrate was identified and tested. Helium pumping performance of this combination was comparable to that of the charcoal braze system. Environmental tests showed the charcoal's susceptibility to vacuum chamber contamination. Performance degradation followed exposure of ambient temperature charcoal to a vacuum for prolonged periods. Maintaining a liquid nitrogen-cooled shield between the charcoal and the source of contamination prevented this degradation. A combination of bake-out and LN shielding effected recovery of degraded performance.

  2. Alexandria's Eastern Harbor, Egypt: Pollen, microscopic charcoal, and the transition from natural to human-modified basin

    USGS Publications Warehouse

    Stanley, J.-D.; Bernhardt, C.E.

    2010-01-01

    Pollen and microscopic charcoal examined in Holocene sediment core samples record major environmental modifications affecting Alexandria's Eastern Harbor through time. We assess whether such changes on Egypt's coastal margin were influenced primarily by natural, or natural plus human, or primarily human factors. We focus on (1) the times when pollen assemblages and microscopic charcoal content changed in the core, (2) how they changed, and (3) why this occurred. The analysis takes into account the core's stratigraphy, regional climate variability, human history, and local archaeological record. Four pollenmicroscopic charcoal zones are identified. The earliest change occurred at ca. 6000 YBP, during Egypt's earlier Predynastic (Neolithic) period, coinciding with a lithologic break from sand to muddy sand. Pollen during this time indicates a transition to a much drier climate rather than effects of human activity. The second change in pollen occurred 3600-2900 YBP, during a period of continued aridity with no lithologic variation in this core interval. Pollen (cereal taxa, agricultural weeds, grape) and a sharp increase in microscopic charcoal indicate that human activity became prevalent at least 700 y before Alexander the Great's arrival in this region, and these results highlight the transition from a largely natural climatecontrolled environment to one influenced by both climate and anthropogenic activity. The third shift up-core in pollen assemblages is dated at ca. 2300 YBP, at the boundary between a sand and mud unit. It coincides with construction by the Ptolemies of the Heptastadion between Alexandria and Pharos Island. From this time onward, harbor sediment in the nearly enclosed catchment basin indicates a near-continuous record of dominant proximal human activity. ?? 2010 Coastal Education and Research Foundation.

  3. Efficacy of charcoal cathartic versus ipecac in reducing serum acetaminophen in a simulated overdose.

    PubMed

    McNamara, R M; Aaron, C K; Gemborys, M; Davidheiser, S

    1989-09-01

    The traditional role of gastric emptying as the initial step in the management of the poisoned patient has recently been questioned; immediate activated charcoal administration has been recommended by some. In the setting of acetaminophen overdose, ipecac-induced emesis may interfere with subsequent oral antidotal therapy. Therefore, we conducted a study to compare the efficacy of initial therapy with ipecac with therapy with activated charcoal-cathartic in a simulated acetaminophen overdosage. Ten healthy volunteers participated in a randomized, crossover trial. Subjects ingested 3.0 g acetaminophen, followed by either no intervention, 30 mL syrup of ipecac, or 50 g activated charcoal-sorbitol solution at one hour. Serial acetaminophen levels were determined at intervals over eight hours. Both interventions significantly reduced the area under the curve compared with control (P less than .05). When comparing ipecac with activated charcoal-cathartic, no significant difference was noted among these groups. PMID:2569851

  4. Calibration of diffusion barrier charcoal detectors using a semi-empirical expression.

    PubMed

    Montero Cabrera, M E; Sujo, L Colmenero; Villalba, L; Peinado, J Sáenz; Jiménez, A Cano; Miranda, A López; Peraza, E F Herrera

    2003-10-01

    Several calibration settings of diffusion barrier charcoal canister (DBCC) detectors for measuring radon concentration in air were studied. A set of functions and graphs were developed for relations between radon concentration in air and adsorbed activity in DBCC, when calibrated in small chambers. Both the integration time for 10% of DBCC of a batch, and the radon adsorption coefficient for the activated charcoal used in these detectors, were determined. Thus, a semi-empirical expression for detector calibration was applied. PMID:14522237

  5. Characterization of Soil Samples of Enzyme Activity

    ERIC Educational Resources Information Center

    Freeland, P. W.

    1977-01-01

    Described are nine enzyme essays for distinguishing soil samples. Colorimetric methods are used to compare enzyme levels in soils from different sites. Each soil tested had its own spectrum of activity. Attention is drawn to applications of this technique in forensic science and in studies of soil fertility. (Author/AJ)

  6. What can we tell from particle morphology in Mesozoic charcoal assemblages?

    NASA Astrophysics Data System (ADS)

    Crawford, Alastair; Belcher, Claire

    2015-04-01

    Sedimentary charcoal particles provide a valuable record of palaeofire activity on both human and geological timescales. Charcoal is both an unambiguous indicator of wildfire, and a means of preservation of plant material in an inert form; thus it records not only the occurrence and extent of wildfire, but also the species affected. While scanning electron microscopy can be usefully employed for precise taxonomic identification of charcoals, the time and cost associated with this limit the extent to which the technique is employed. Morphometric analysis of mesocharcoal particles (c. 125-1000 µm) potentially provides a simple method for obtaining useful information from optical microscopy images. Grass fires have been shown to produce mesocharcoal particles with a higher length-to-width ratio than woodland fuel sources. In Holocene archives, aspect ratio measurements are thus used to infer the broad taxonomic affinity of the burned vegetation. Since Mesozoic charcoals display similarly heterogeneous morphologies, we investigate whether there is a similar potential to infer the broad botanical affinities of Mesozoic charcoal assemblages from simple morphological metrics. We have used image analysis to analyse a range of Jurassic and Cretaceous sedimentary rocks representing different vegetation communities and depositional environments, and also to determine the range of charcoal particle morphologies which can be produced from different modern taxa under laboratory conditions. We find that modern charcoals break down into mesocharcoal particles of very variable aspect ratio, and this appears to be dependent on taxonomic position. Our analysis of fragmented laboratory-produced charcoals indicates that pteridophytes produce much more elongate particles than either conifers or non-grass angiosperms. We suggest that for charcoal assemblages that predate the evolution of grasses, high average aspect ratios may be a useful indicator of the burning of a pteridophyte

  7. 49 CFR 176.405 - Stowage of charcoal.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Stowage of charcoal. 176.405 Section 176.405... Materials § 176.405 Stowage of charcoal. (a) Before stowing charcoal Division 4.2 (flammable solid), UN 1361... petroleum product, a vegetable or animal oil, nitrate, or sulfur, must be removed. (b) Charcoal packed...

  8. 49 CFR 176.405 - Stowage of charcoal.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Stowage of charcoal. 176.405 Section 176.405... Materials § 176.405 Stowage of charcoal. (a) Before stowing charcoal Division 4.2 (flammable solid), UN 1361... petroleum product, a vegetable or animal oil, nitrate, or sulfur, must be removed. (b) Charcoal packed...

  9. 49 CFR 176.405 - Stowage of charcoal.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Stowage of charcoal. 176.405 Section 176.405... Materials § 176.405 Stowage of charcoal. (a) Before stowing charcoal Division 4.2 (flammable solid), UN 1361... petroleum product, a vegetable or animal oil, nitrate, or sulfur, must be removed. (b) Charcoal packed...

  10. 49 CFR 176.405 - Stowage of charcoal.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Stowage of charcoal. 176.405 Section 176.405... Materials § 176.405 Stowage of charcoal. (a) Before stowing charcoal Division 4.2 (flammable solid), UN 1361... petroleum product, a vegetable or animal oil, nitrate, or sulfur, must be removed. (b) Charcoal packed...

  11. 49 CFR 176.405 - Stowage of charcoal.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Stowage of charcoal. 176.405 Section 176.405... Materials § 176.405 Stowage of charcoal. (a) Before stowing charcoal Division 4.2 (flammable solid), UN 1361... petroleum product, a vegetable or animal oil, nitrate, or sulfur, must be removed. (b) Charcoal packed...

  12. Development of an incineration system for pulverized spent charcoal

    SciTech Connect

    Furukawa, Osamu; Shibata, Minoru; Kani, Koichi

    1995-12-31

    In the existing charcoal treatment system granular charcoal is charged directly into an incinerator together with other combustible waste. Since the combustion rate of the charcoal is slow in this system, there is a problem that unburnt charcoal accumulates at the bottom of the incinerator, when incineration is performed for an extended period of time. To prevent this difficulty, the combustion rate of the charcoal must be limited to 6 kg/h. To increase the incineration rate of charcoal, the authors have developed a system in which the charcoal is pulverized and incinerated while it is mixed with propane gas. The operational performance of this system was tested using an actual equipment.

  13. Should we do early and frequent charcoal hemoperfusion in phenytoin toxicity?

    PubMed

    Sahoo, Jyoti Narayan; Gurjar, Mohan

    2016-02-01

    Phenytoin toxicity or adverse drug reaction is common due to its narrow therapeutic window. Mild and moderate toxicity require supportive care and enteral activated charcoal. In severe toxicity, charcoal hemoperfusion (CHP) have been shown to decrease serum phenytoin half-life and early recovery. Here, we report two cases with phenytoin toxicity who showed marked clinical improvement after early and frequent CHP treatment. PMID:27076716

  14. Should we do early and frequent charcoal hemoperfusion in phenytoin toxicity?

    PubMed Central

    Sahoo, Jyoti Narayan; Gurjar, Mohan

    2016-01-01

    Phenytoin toxicity or adverse drug reaction is common due to its narrow therapeutic window. Mild and moderate toxicity require supportive care and enteral activated charcoal. In severe toxicity, charcoal hemoperfusion (CHP) have been shown to decrease serum phenytoin half-life and early recovery. Here, we report two cases with phenytoin toxicity who showed marked clinical improvement after early and frequent CHP treatment. PMID:27076716

  15. Mechanically robust, chemically inert superhydrophobic charcoal surfaces.

    PubMed

    Xie, Jian-Bo; Li, Liang; Knyazeva, Anastassiya; Weston, James; Naumov, Panče

    2016-08-11

    We report a fast and cost-effective strategy towards the preparation of superhydrophobic composites where a double-sided adhesive tape is paved with charcoal particles. The composites are mechanically robust, and resistant to strong chemical agents. PMID:27405255

  16. Mapping the Legacies of Historic Charcoal Production

    NASA Astrophysics Data System (ADS)

    Schneider, A.; Raab, A.; Raab, T. A.; Takla, M.; Nicolay, A.; Rösler, H.

    2014-12-01

    The historic production of charcoal is an important component of the late Holocene fire history for many landscapes. Charcoal production can have numerous effects on ecosystems, e.g., through changes in forest area and structure, or through the effects of pyrolysis, charcoal and ash addition to soils. To assess such effects, it is necessary to understand the spatial extent and patterns of historic charcoal production, which has so far hardly been approached for the Northern European Lowlands. In the forefield of the open-cast mine Jänschwalde (north of Cottbus, Germany), archaeological excavations have revealed one of the largest charcoal production fields described so far. For this area, we applied and evaluated different methods for mapping the spatial distribution of charcoal kiln remains. We present methods and results of our work in this exceptionally well-described charcoal production field and of additional studies on kiln site distribution in regions of the Northern European Lowlands. The large-scale excavations in the mine forefield provide exact information on kiln site geometry. Using airborne laser scanning elevation models, the mapping of kiln sites could be extended to areas beyond the mine forefield. To detect kiln sites for larger areas, an automated GIS based mapping routine, based on a combination of morphometric parameters, was developed and evaluated. By manual digitization from Shaded Relief Maps, more than 5000 kiln sites in an area of 32 km2 were detected in the Jänschwalde mine forefield, with 1355 kiln sites that are wider than 12 m. These relatively large kiln sites could be mapped with detection rates that are close to those of manual digitization using the automated routine. First results for different study areas indicate that charcoal production is a so far underestimated component of the land use history in many parts of the Northern European Lowlands.

  17. Fluidized bed charcoal particle production system

    SciTech Connect

    Sowards, N.K.

    1985-04-09

    A fluidized bed charcoal particle production system, including apparatus and method, wherein pieces of combustible waste, such as sawdust, fragments of wood, etc., are continuously disposed within a fluidized bed of a pyrolytic vessel. Preferably, the fluidized bed is caused to reach operating temperatures by use of an external pre-heater. The fluidized bed is situated above an air delivery system at the bottom of the vessel, which supports pyrolysis within the fluidized bed. Charcoal particles are thus formed within the bed from the combustible waste and are lifted from the bed and placed in suspension above the bed by forced air passing upwardly through the bed. The suspended charcoal particles and the gaseous medium in which the particles are suspended are displaced from the vessel into a cyclone mechanism where the charcoal particles are separated. The separated charcoal particles are quenched with water to terminate all further charcoal oxidation. The remaining off-gas is burned and, preferably, the heat therefrom used to generate steam, kiln dry lumber, etc. Preferably, the bed material is continuously recirculated and purified by removing tramp material.

  18. The performance of charcoal-based radon detection under time-varying radon conditions: Experimental and theoretical results

    SciTech Connect

    Sextro, R.G.; Lee, D.D.

    1988-10-01

    Radon adsorption by charcoal is a widely used technique for measuring indoor radon concentration, particularly when short-term results are desired. There are several different devices available, ranging from permeable envelopes filled with charcoal and open-face charcoal-filled canisters to devices incorporating diffusion limiting features to reduce losses of radon due to desorption. However, the integration characteristics of these samplers are not well understood, particularly under conditions of highly varying radon concentrations. A model for predicting the response of various types of charcoal based detectors to time-variant radon concentrations has been developed; the model predictions compare well with results from chamber experiments. Both the experimental and theoretical results have also been compared with integrated continuous-sampling measurements. The implications of these comparisons for use of charcoal for screening measurements is discussed. 5 refs., 4 figs., 2 tabs.

  19. Comparing modelled fire dynamics with charcoal records for the Holocene

    NASA Astrophysics Data System (ADS)

    Brücher, Tim; Brovkin, Victor; Kloster, Silvia; Marlon, Jennifer; Power, Mitch

    2014-05-01

    An Earth System model of intermediate complexity, CLIMBER-2, and land surface model JSBACH that includes dynamic vegetation, carbon cycle, and fire regime are used for simulation of natural fire dynamics through the last 8,000 years. To compare the fire model results with the charcoal reconstructions, several output variables of the fire model (burned area, carbon emissions) and several approaches of model output processing are tested. The z-scores out of charcoal dataset have been calculated for the period 8,000 to 200 BP to exclude a period of strong anthropogenic forcing during the last two centuries. The model analysis points mainly to an increasing fire activity during the Holocene for most of the investigated areas, which is in good correspondence to reconstructed fire trends out of charcoal data for most of the tested regions, while for few regions such as Europe the simulated trend and the reconstructed trends are different. The difference between the modeled and reconstructed fire activity could be due to absence of the anthropogenic forcing in the model simulations, but also due to limitations of model assumptions for modeling fire dynamics. For the model trends, the usage of averaging or z-score processing of model output resulted in similar directions of trend. Therefore, the approach of fire model output processing does not effect results of the model-data comparison. Global fire modeling is still in its infancy; improving our representations of fire through validation exercises such as what we present here is thus essential before testing hypotheses about the effects of extreme climate changes on fire behavior and potential feedbacks that result from those changes. Brücher, T., Brovkin, V., Kloster, S., Marlon, J. R., and Power, M. J.: Comparing modelled fire dynamics with charcoal records for the Holocene, Clim. Past Discuss., 9, 6429-6458, doi:10.5194/cpd-9-6429-2013, 2013.

  20. A contribution to the identification of charcoal origin in Brazil II - Macroscopic characterization of Cerrado species.

    PubMed

    Gonçalves, Thaís A P; Nisgoski, Silvana; Oliveira, Julia S; Marcati, Carmen R; Ballarin, Adriano W; Muñiz, Graciela I B

    2016-05-13

    The Brazilian Cerrado is the richest savanna in the world. It is also one of the biomes more threatened in the country and a hotspot for conservation priorities. The main causes of deforestation in Cerrado are agricultural practices, livestock and charcoal production. Although charcoal has a minor impact, its consumption represents the deforestation of 16.000 Km² of the Cerrado. To contribute for the biomes's conservation it is very important to improve forestry supervision. Thus, in this work we present the macroscopic characterization of charcoal from 25 Cerrado's species. We simulate the real conditions of forest controllers by using the magnifications of 10x, 25x and 65x. Likewise, the charcoals micrographs are all of transverse sections due to the larger amount of anatomical information. We also analyzed texture, brightness, vitrification, ruptures and some special features. The species present several differences in their anatomical structure. Although some of them are very unique, this work does not intent to identify charcoals only by macroscopic analyses. But it might give directions to future identification of genera or species. It also provides knowledge for government agents to verify the documents of forestry origin by fast analyzing a sample of charcoal itself. PMID:27192198

  1. Neutron activation analysis of wheat samples.

    PubMed

    Galinha, C; Anawar, H M; Freitas, M C; Pacheco, A M G; Almeida-Silva, M; Coutinho, J; Maçãs, B; Almeida, A S

    2011-11-01

    The deficiency of essential micronutrients and excess of toxic metals in cereals, an important food items for human nutrition, can cause public health risk. Therefore, before their consumption and adoption of soil supplementation, concentrations of essential micronutrients and metals in cereals should be monitored. This study collected soil and two varieties of wheat samples-Triticum aestivum L. (Jordão/bread wheat), and Triticum durum L. (Marialva/durum wheat) from Elvas area, Portugal and analyzed concentrations of As, Cr, Co, Fe, K, Na, Rb and Zn using Instrumental Neutron Activation Analysis (INAA) to focus on the risk of adverse public health issues. The low variability and moderate concentrations of metals in soils indicated a lower significant effect of environmental input on metal concentrations in agricultural soils. The Cr and Fe concentrations in soils that ranged from 93-117 and 26,400-31,300mg/kg, respectively, were relatively high, but Zn concentration was very low (below detection limit <22mg/kg) indicating that soils should be supplemented with Zn during cultivation. The concentrations of metals in roots and straw of both varieties of wheat decreased in the order of K>Fe>Na>Zn>Cr>Rb>As>Co. Concentrations of As, Co and Cr in root, straw and spike of both varieties were higher than the permissible limits with exception of a few samples. The concentrations of Zn in root, straw and spike were relatively low (4-30mg/kg) indicating the deficiency of an essential micronutrient Zn in wheat cultivated in Portugal. The elemental transfer from soil to plant decreases with increasing growth of the plant. The concentrations of various metals in different parts of wheat followed the order: Root>Straw>Spike. A few root, straw and spike samples showed enrichment of metals, but the majority of the samples showed no enrichment. Potassium is enriched in all samples of root, straw and spike for both varieties of wheat. Relatively to the seed used for cultivation, Jord

  2. New emission controls for Missouri batch-type charcoal kilns

    SciTech Connect

    Yronwode, P.; Graf, W.J.

    1999-07-01

    Charcoal kilns have been exempted from air emission regulation in the state of Missouri. Today, 80% of US charcoal production takes place in Missouri. As a result of a petition filed by people in the area around an installation in southern Missouri, the US Environmental Protection Agency (EPA) set up air monitors and measured ambient air levels at that charcoal manufacturing installation. These monitors yielded the highest particulate matter less than 10 micron (PM{sub 10}) levels ever recorded in the state. Earlier stack testing at another charcoal manufacturing installation indicated that toxics and carcinogens are present in charcoal kiln air emissions. A Charcoal Kiln Workgroup was formed to determine the Best Available Control Technology (BACT) for charcoal kilns and to draft a charcoal kiln rule that requires BACT. The BACT report determined that afterburners were suitable for controlling emissions from batch-type charcoal kilns. In addition, the charcoal industry supported incorporating the BACT limits and requirements into an enforceable state rule and submitting this rule to the EPA for federal approval. A consent agreement between the EPA and three major charcoal companies was signed with provisions to install, operate, and maintain emission control devices on charcoal kilns. This agreement was to settle complaints alleging that the three major charcoal producers had failed to report toxic air emissions to federal and state regulators. The agreement provided that industry would install control devices on a set schedule with some charcoal kilns being shut down.

  3. Adsorption of dimethyl sulfide from aqueous solution by a cost-effective bamboo charcoal.

    PubMed

    Wang, Ming; Huang, Zheng-Hong; Liu, Guangjia; Kang, Feiyu

    2011-06-15

    The adsorption of dimethyl sulfide from an aqueous solution by a cost-effective bamboo charcoal from Dendrocalamus was studied in comparison with other carbon adsorbents. The bamboo charcoal exhibited superior adsorption on dimethyl sulfide compared with powdered activated carbons at different adsorbent dosages. The adsorption characteristics of dimethyl sulfide onto bamboo charcoal were investigated under varying experimental conditions such as particle size, contact time, initial concentration and adsorbent dosage. The dimethyl sulfide removal was enhanced from 31 to 63% as the particle size was decreased from 24-40 to >300 mesh for the bamboo charcoal. The removal efficiency increased with increasing the adsorbent dosage from 0.5 to 10mg, and reached 70% removal efficiency at 10mg adsorbed. The adsorption capacity (μg/g) increased with increasing concentration of dimethyl sulfide while the removal efficiency decreased. The adsorption process conforms well to a pseudo-second-order kinetics model. The adsorption of dimethyl sulfide is more appropriately described by the Freundlich isotherm (R(2), 0.9926) than by the Langmuir isotherm (R(2), 0.8685). Bamboo charcoal was characterized by various analytical methods to understand the adsorption mechanism. Bamboo charcoal is abundant in acidic and alcohol functional groups normally not observed in PAC. A distinct difference is that the superior mineral composition of Fe (0.4 wt%) and Mn (0.6 wt%) was detected in bamboo charcoal-elements not found in PAC. Acidic functional group and specific adsorption sites would be responsible for the strong adsorption of dimethyl sulfide onto bamboo charcoal of Dendrocalamus origin. PMID:21549503

  4. EFFECTS OF ACTIVATED CHARCOAL FILTRATION AND OZONATION ON HYDROCARBON AND CARBONYL LEVELS OF AMBIENT AIR USED IN CONTROLLED-EXPOSURE CHAMBER STUDIES OF AIR POLLUTANT HUMAN HEALTH EFFECTS

    EPA Science Inventory

    Air sampling experiments were done in 1985, 1987, and 1993 at the human-exposure chamber facility of the U.S. EPA Health Effects Research Laboratory in Chapel Hill, NC. easurements of VOC's by GC-FID and aldehyde measurements by the DNPH silica gel cartridge method were made, com...

  5. Enhanced photocatalytic degradation and adsorption of methylene blue via TiO2 nanocrystals supported on graphene-like bamboo charcoal

    NASA Astrophysics Data System (ADS)

    Wu, Fangjun; Liu, Wei; Qiu, Jielong; Li, Jinzhen; Zhou, Wuyi; Fang, Yueping; Zhang, Shuting; Li, Xin

    2015-12-01

    In this study, a novel efficient photocatalytic nanomaterial, TiO2 nanocrystals supported on graphene-like bamboo charcoal, has been successfully synthesized via a facile multi-step process. The structural and optical properties of the as-prepared samples were characterized by different techniques, such as X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-vis absorption spectroscopy, photoluminescence spectra (PL), Raman spectra and nitrogen adsorption-desorption isotherms. The photocatalytic activities under sunlight were evaluated by the degradation of methylene blue (MB). The results indicated that the ternary hybrid photocatalysts exhibited much higher photocatalytic activities toward the degradation of MB than the pure TiO2 under UV light irradiation. Moreover, the optimum weight content of graphene-like bamboo charcoal in composite photocatalysts was 6 wt% for achieving the maximum photocatalytic degradation rate. The apparent rate constant of the best sample (0.0509 min-1) was about 3 times greater than that of the commercial P25 (0.0170 min-1). The adsorption and degradation kinetics of MB can be described by the pseudo-first-order model and apparent first-order kinetics model, respectively. The highly enhanced photocatalytic performance was attributed to the synergetic effect of graphene-like carbon and bamboo charcoal, which lead to the promoted charge separation and reduction reaction of oxygen, and enhanced adsorption capacities of MB, respectively. The composite photocatalysts displayed a high photochemical stability under repeated irradiation. This work may provide new insights and understanding on the graphene-like bamboo charcoal as an excellent support for photocatalyst nanoparticles to enhance their visible-light photocatalytic activity.

  6. Effect of Charcoal Volatile Matter Content and Feedstock on Soil Microbe-Carbon-Nitrogen Dynamics

    NASA Astrophysics Data System (ADS)

    McClellan, T.; Deenik, J. L.; Hockaday, W. C.; Campbell, S.; Antal, M. J., Jr.

    2010-12-01

    Charcoal has important biogeochemical implications in soil—first as a means to sequester carbon, and second as a soil conditioner to potentially enhance soil quality and fertility. Volatile matter (VM) content is a property of charcoal which describes its degree of thermal alteration, or carbonization. Results from greenhouse experiments have shown that plant growth can be negatively affected by charcoals with high VM content (20-35%), with and without fertilizer supplements, whereas low VM charcoal (6-9%) increased plant growth when combined with fertilizer. We conducted two laboratory studies to characterize the VM content of charcoals derived from two feedstocks (corncob and kiawe) and relate observed differences to key aspects of soil fertility. Using Fourier transform infrared spectroscopy (FTIR), 13C nuclear magnetic resonance (NMR), total phenol content (using a Prussian blue colorimetric assay), and gas chromatography-mass spectrometry (GC-MS), we found that the VM content of charcoal primarily consisted of alkanes, oxygen-substituted alkanes, and phenolic compounds. However, the GC-MS data indicated that charcoals can differ vastly in their extractable fraction, depending upon both VM content and feedstock. In a second set of experiments, we examined the effect of VM content and feedstock on soil microbial activity, available nitrogen (N), and soluble carbon (C). High VM corncob charcoals significantly enhanced microbial activity, coupled with net reduction in available N and soluble C. For a given feedstock, the extent of this effect was dependent upon VM content. However, the overall effect of VM content on microbial dynamics was apparently related to the composition of the acetone-extractable fraction, which was particularly important when comparing two charcoals derived from different feedstocks but with the equivalent VM contents. Removing the acetone-extractable fraction from the 23% VM corncob charcoal significantly reduced the enhancement of

  7. Holocene Charcoal Deposition From Brazilian Forest Fires

    NASA Astrophysics Data System (ADS)

    Turcq, B.; Cordeiro, R. C.; Albuquerque, A. S.; Simoes, F. L.; Sifeddine, A.

    2004-12-01

    Determination of charcoal accumulation rate in lacustrine sediments allows to reconstruct the fire history of the region surrounding the lake. Our studies have been achieved in three Amazonian sites and one site in Atlantic rainforest. Charcoal fragments are identified and counted under a microscope. Typical size of these charcoals is around ten micrometers and they probably have been subject to eolian transport. The highest charcoal accumulation rates were obtained in sediments from Middle Holocene in Carajás region, eastern Amazonia. These rates are on the same order than the present day charcoal accumulation rate in Alta Floresta, a region of Amazonia which is being submited to intense slash and burn. The lowest values were found in Lagoa da Pata in Sao Gabriel da Cachoeira, a very humid area in western Amazon. We observed from the D. Helvécio record, in the Atlantic rainforest, fire occurrences from 8,400 to 6,400 cal years BP. For Carajás lake, surrounded by tropical rain forest, we had identified fires during the period between 8,000 and 5,300 cal years BP. Finally, the lake Caracarana, which is surrounded by grass savanna, showed a record of main fire occurrence phase at 9,750 cal yrs BP and a second phase marked by charcoal peaks at 7,680, 6,990 and 6,460 cal yrs BP. The synchronism of the fire occurrence periods in different Brazilian regions is related to the Middle Holocene dry climate phase provoked by the low summer insolation. Differences in the accumulation rates can be attributed to differences in biomass availability and fire return time. The carbon released in the atmosphere by this fires must have contributed to the observed increase of CO2, poorer in 13C, during the middle Holocene.

  8. Chemical changes in soil charcoal of differing ages inferred from DRIFT spectra

    NASA Astrophysics Data System (ADS)

    Hobley, E. U.; Willgoose, G. R.; Frisia, S.; Jacobsen, G.

    2012-04-01

    Visible charcoal fragments were manually isolated from a sandy soil from the Southern Highlands of NSW, Australia, at depths of 0 - 30 cm and 30 - 60 cm. In the topsoil, the charcoal had a radiocarbon age of 85 ± 35 years BP, whereas the charcoal from the 30 - 60 cm layer was radiocarbon dated at 2540 ± 35 years BP. Diffuse reflectance FTIR (DRIFT) spectra of the charcoal reveal differences in both the number of peaks detected and their magnitudes. In the IR region 750 - 3800 cm-1, the charcoal from the lower depth had less peaks (140) than that of the topsoil (217). In the 1400 - 1600 cm-1 region, generally attributed to aromatics, the peaks were larger and more numerous (22 peaks) in the 0 - 30 cm sample than those of the 30 - 60 cm depth (14 peaks). The C-H stretch of alkenes and aromatics (3000 - 3100 cm-1) was similar at both depths, but the peak generally associated with the C-H stretch of alkanes (methyl and methylene groups) at 2850 - 3000 cm-1 was smaller in 30 - 60 cm depth than in the topsoil. In contrast to the reduction in aromatic and alkane signatures, oxidised forms were more pronounced in the older, deeper charcoal. Peaks associated with the free hydroxyl O-H stretch (alcohols and phenols) at 3640 - 3610 cm-1, carboxylic acids (910 - 950 cm-1), aliphatic O-H (alcohols) (1050 - 1150 cm-1) and cellulose-like structures (1020 cm-1), which contain a large number of uncondensed, oxidised rings, were larger in the charcoal from 30 - 60 cm than in that from the topsoil. Our results confirm that charcoal is highly persistent in soils, being retained for millennia. Aromatic structures are present in both younger and older charcoal, but decay leads to a reduction in the number and area of peaks detected at 1400 - 1600 cm-1, indicating less aromaticity. Alkane C-H also decreases with aging, probably attributable to its preferential degradation by soil microbes compared with condensed aromatic structures. Concurrent with diminished aromatic and alkane

  9. Recovery of Technetium Adsorbed on Charcoal

    SciTech Connect

    Engelmann, Mark D.; Metz, Lori A.; Ballou, Nathan E.

    2006-05-01

    Two methods capable of near complete recovery of technetium adsorbed on charcoal are presented. The first involves liquid extraction of the technetium from the charcoal by hot 4M nitric acid. An average recovery of 98% (n=3) is obtained after three rounds of extraction. The second method involves dry ashing with air in a quartz combustion tube at 400-450 C. This method yields an average recovery of 96% (n=5). Other thermal methods were attempted, but resulted in reduced recovery and incomplete material balance

  10. Research on Bamboo Charcoal Bonded Grinding Wheel and Its Mechanical Properties

    NASA Astrophysics Data System (ADS)

    Li, Wei; Xu, Minjie; Zhan, Fangyong; Jin, Mingsheng

    2014-08-01

    In this paper, a new type of grinding wheel and its manufacturing production process are introduced. The new BCB (Bamboo Charcoal Bond) grinding wheel was made of bamboo charcoal, phenolic resin and abrasive powder with higher press and temperature. To investigate its mechanical features, such as Rockwell hardness, resistance to abrasion, and resistance to pressure, some experiments on three BCB samples with different Resin weight ratios 20%, 25%, 30%, were carried out. The results showed that the BCB sample with proper moulding process and Resin weight ratio had better performance.

  11. SOURCE ASSESSMENT: CHARCOAL MANUFACTURING, STATE-OF-THE-ART

    EPA Science Inventory

    This document reviews the state of the art of air emissions from charcoal manufacture. The composition, quality, and rate of emissions, and their environmental effects are described. Charcoal is the solid material remaining after the pyrolysis of carbonaceous materials, primarily...

  12. Charcoal records reveal past occurrences of disturbances in the forests of the Kisangani region, Democratic Republic of the Congo

    NASA Astrophysics Data System (ADS)

    Tshibamba Mukendi, John; Hubau, Wannes; Ntahobavuka, Honorine; Boyemba Bosela, Faustin; De Cannière, Charles; Beeckman, Hans

    2014-05-01

    Past disturbances have modified local density, structure and floristic composition of Central African rainforests. As such, these perturbations represent a driving force for forest dynamics and they were presumably at the origin of present-day forest mosaics. One of the most prominent disturbances within the forest is fire, leaving behind charcoal as a witness of past forest dynamics. Quantification and identification of ancient charcoal fragments found in soil layers (= pedoanthracology) allows a detailed reconstruction of forest history, including the possible occurrence of past perturbations. The primary objective of this study is to present palaeoenvironmental evidence for the existence of past disturbances in the forests of the Kisangani region (Democratic Republic of the Congo) using a pedoanthracological approach. We quantified and identified charcoal fragments from pedoanthracological excavations in the Yangambi, Yoko, Masako and Kole forest regions. Charcoal sampling was conducted in pit intervals of 10 cm, whereby pottery fragments were also registered and quantified. Floristic identifications were conducted using former protocols based on wood anatomy, which is largely preserved after charcoalification. 14 excavations were conducted and charcoal was found in most pit intervals. Specifically, 52 out of 56 sampled intervals from the Yangambi forest contained charcoal, along with 47 pit intervals from the Yoko forest reserve, 34 pit intervals from the Masako forest and 16 from the Kole forest. Highest specific anthracomasses were recorded in Yoko (167 mg charcoal per kg soil), followed by Yangambi (133 mg/kg), Masako (71,89 mg/kg) and finally Kole (42,4 mg/kg). Charcoal identifications point at a manifest presence of the family of Fabaceae (Caesalpinioideae). This family is characteristic for the tropical humid rainforest. The presence of charcoal fragments from these taxa, associated with pottery sherds on different depths within the profiles, suggests

  13. Characterization of coal and charcoal by alpha-particle and gamma-ray spectrometry

    NASA Astrophysics Data System (ADS)

    Carrasco Lourtau, A. M.; Rubio Montero, M. P.; Jurado Vargas, M.

    2015-11-01

    Although coal and charcoal have similar physical and chemical characteristics, there are several crystallographic procedures used to distinguish and characterize them. But if the matrix is crushed, there is no standard procedure to distinguish coal from charcoal. In this work, a procedure to characterize coal and charcoal samples based on the radioactive content is proposed. The first assay is by gamma-ray spectrometry, which allows a part of the radioactive content to be determined rapidly and non-destructively. Then, alpha-particle spectrometry is applied to assay the content of those radionuclides which are difficult to determine precisely by gamma-ray spectrometry. This second technique requires prior chemical purification of the carbon sample in order to separate the corresponding radionuclides of interest.

  14. Charcoal from the pyrolysis of rapeseed plant straw-stalk

    SciTech Connect

    Karaosmanoglu, F.; Tetik, E.

    1999-07-01

    Charcoal is an important product of pyrolysis of biomass sources. Charcoal can be used for domestic, agricultural, metallurgical, and chemical purposes. In this study different characteristics of charcoal, one of the rape seed plant straw-stalk pyrolysis product, was researched and presented as candidates.

  15. Sawdust and Charcoal: Fuel for Raku.

    ERIC Educational Resources Information Center

    Brisson, Harriet E.

    1980-01-01

    Raku is an ancient Japanese process of firing pottery in which the bisqued piece is glazed and placed in a preheated kiln. Described are the benefits of substituting sawdust and charcoal for firing pottery by those people who do not have access to a kiln. (KC)

  16. Charcoal and the Record of Fire-related Sedimentation in Holocene Alluvial Sediments

    NASA Astrophysics Data System (ADS)

    Meyer, G. A.

    2006-12-01

    Over the last few decades, rising temperatures and ensuing severe wildfires in the western USA cordillera have provided the opportunity to examine processes and deposits of postfire sedimentation on alluvial fans and floodplains. Most events are generated by widespread surface runoff from intense convective-storm precipitation on severely burned slopes. Flow processes range from debris flow to sediment-charged water floods. Muddy debris flows best preserve coarse charcoal in fan deposits, whereas gravelly debris flows often comminute charcoal into fine particles. As charcoal remains suspended in high-energy hyperconcentrated and water floods, only their fine-grained deposits typically contain much charcoal. Charcoal is locally concentrated in low-energy fluvial deposits, but displays increasing evidence for reworking with distance from source. Charred vegetation and litter marking burned soil surfaces may be preserved under postfire fan and fluvial sediments. Modern deposits provide models for identification of Holocene fire-related sediments and estimates of paleofire severity. AMS 14C dating of discrete charcoal fragments allows sample selection to minimize errors of sample age > fire age. Fires are incompletely recorded in the event stratigraphy of one fan, but larger populations of 14C ages from numerous fans permit composite probability distributions that represent centennial- to millennial-scale changes in fire-related sedimentation across a study area. Records from Yellowstone and central Idaho indicate the large role of fire in episodic erosion across a range of conifer forests, most strongly during severe, multidecadal droughts in warmer periods (e.g. in Medieval time 900-1300 AD). In central Idaho, identification of charcoal macrofossils indicates broadly similar, aspect-controlled forest compositions over the last 3000 yr. Emerging data from the Sacramento Mountains, New Mexico, show rapid fan aggradation due to fire-related events in the warm middle

  17. The environmental impact on air quality and exposure to carbon monoxide from charcoal production in southern Brazil.

    PubMed

    Gomes, Gabriel Meneghetti Faé; Encarnação, Fábio

    2012-07-01

    Black wattle silviculture is an important activity in southern Brazil. Much of the wood is used in the production of charcoal and the pyrolysis products impacts on air quality. This paper estimates the level of atmospheric contamination from the production of charcoal in one region of Brazil. We describe a low-cost charcoal kiln that can capture condensable gases and we estimate the levels of exposure of kiln workers to carbon monoxide. The latter results indicated that exposure to carbon monoxide can be reduced from an average of 950 ppm to 907 ppm and the mass of gases reduced by 16.8%. PMID:22541721

  18. Comparing modeled fire dynamics with charcoal records for the Holocene

    NASA Astrophysics Data System (ADS)

    Bruecher, T.; Brovkin, V.; Kloster, S.; Marlon, J. R.; Power, M. J.

    2013-12-01

    An Earth System model of intermediate complexity, CLIMBER-2, and land surface model JSBACH that includes dynamic vegetation, carbon cycle, and fire regime are used for simulation of natural fire dynamics through the last 8,000 years. To compare the fire model results with the charcoal reconstructions, several output variables of the fire model (burned area, carbon emissions) and several approaches of model output processing are tested. The z-scores out of charcoal dataset have been calculated for the period 8,000 to 200 BP to exclude a period of strong anthropogenic forcing during the last two centuries. The model analysis points mainly to an increasing fire activity during the Holocene for most of the investigated areas, which is in good correspondence to reconstructed fire trends out of charcoal data for most of the tested regions, while for few regions such as Europe the simulated trend and the reconstructed trends are different. The difference between the modeled and reconstructed fire activity could be due to absence of the anthropogenic forcing in the model simulations, but also due to limitations of model assumptions for modeling fire dynamics. For the model trends, the usage of averaging or z-score processing of model output resulted in similar directions of trend. Therefore, the approach of fire model output processing does not effect results of the model-data comparison. Global fire modeling is still in its infancy; improving our representations of fire through validation exercises such as what we present here is thus essential before testing hypotheses about the effects of extreme climate changes on fire behavior and potential feedbacks that result from those changes.

  19. Analysis of alkyl nitrates and selected halocarbons in the ambient atmosphere using a charcoal preconcentration technique

    SciTech Connect

    Atlas, E.; Schauffler, S. )

    1991-01-01

    A method has been developed to measure {ge}C{sub 3} alkyl nitrates and C{sub 1}-C{sub 2} halocarbons, such as perchloroethylene and bromoform, in ambient air. The method preconcentrates analytes on a 5-mg charcoal trap from multiliter volumes of air. Analytes are desorbed from the charcoal with a small volume of solvent and are analyzed by high-resolution gas chromatography with electron capture detection. Laboratory and field tests have been performed to evaluate method precision, analyte breakthrough, and compound recovery from the charcoal. Tests verified that the sampling/analytical system is free from artifact formation under clean to moderately polluted conditions, but further tests are required for areas of high concentrations of hydrocarbons, NO{sub x}, and oxidants. The method allows measurement of halocarbons and {ge}C{sub 3} alkyl nitrates at concentrations in the pptv range.

  20. Emissions from street vendor cooking devices (charcoal grilling). Final report, January 1998--March 1999

    SciTech Connect

    Lee, S.Y.

    1999-06-01

    The report discusses a joint US/Mexican program to establish a reliable emissions inventory for street vendor cooking devices (charcoal grilling), a significant source of air pollutants in the Mexicali-Imperial Valley area of Mexico. Emissions from these devices, prevalent in the streets of Mexicali, Mexico, were investigated experimentally by measuring levels of particulate matter, particle size distributions, volatile and semivolatile organic compounds, aldehydes, and oxides of nitrogen and sulfur, emitted when meat is cooked on a grill over a charcoal fire. To investigate the emission rate, both beef and chicken were tested. Furthermore, both meats were marinated with a mixture similar to that used by the street vendors. Some tests were conducted with non-marinated beef for comparison. Two blank runs were performed sampling charcoal fires without meat. Finally, a simple control device, normally used in an exhaust fan to trap grease over a kitchen stove, was evaluated for its effectiveness in reducing emissions.

  1. Validation of the diffusion-barrier charcoal canister method

    SciTech Connect

    Martz, D.E.; George, J.L.; Mamich, S.T.; Langner, G.H. Jr.

    1989-05-01

    A six-month study was conducted by the Technical Measurements Center, US Department of Energy Grand Junction Projects Office, to evaluate the accuracy and reliability of indoor radon measurements using an intermittent diffusion-barrier charcoal canister sampling protocol. Diffusion-barrier charcoal canisters (DBCC) were exposed for seven days in sixteen occupied residences each week during the 26-week study. The radon concentrations measured by the DBCCs were compared to radon concentrations measured by triplicate sets of four different types of alpha-track monitors and integrated hourly radon concentrations measured by a Pylon Model AB-5 continuous radon monitor. The results were also compared with radon-daughter concentrations measured in these same residences by an Eberline WLM-1 working level monitor. Excellent agreement was observed between the integrated mean radon concentrations measured by the DBCCs compared with the six-month alpha-track results, and between the weekly DBCC readings and average weekly radon concentrations measured by the Pylon radon monitors. An intermittent sampling protocol employing six weekly DBCC measurements spaced approximately every two months throughout the year should provide estimates of the average annual indoor radon concentrations that meet the criteria established for the Grand Junction Remedial Action Program. 9 refs., 17 figs., 9 tabs.

  2. Sample classroom activities based on climate science

    NASA Astrophysics Data System (ADS)

    Miler, T.

    2009-09-01

    We present several activities developed for the middle school education based on a climate science. The first activity was designed to teach about the ocean acidification. A simple experiment can prove that absorption of CO2 in water increases its acidity. A liquid pH indicator is suitable for the demonstration in a classroom. The second activity uses data containing coordinates of a hurricane position. Pupils draw a path of a hurricane eye in a tracking chart (map of the Atlantic ocean). They calculate an average speed of the hurricane, investigate its direction and intensity development. The third activity uses pictures of the Arctic ocean on September when ice extend is usually the lowest. Students measure the ice extend for several years using a square grid printed on a plastic foil. Then they plot a graph and discuss the results. All these activities can be used to improve the natural science education and increase the climate change literacy.

  3. Influence of beer marinades on the reduction of carcinogenic heterocyclic aromatic amines in charcoal-grilled pork meat.

    PubMed

    Viegas, Olga; Moreira, Patrícia S; Ferreira, Isabel M P L V O

    2015-01-01

    The effect of beer marinades on the formation of heterocyclic aromatic amines (HAs) was examined in charcoal-grilled pork. Pilsner, non-alcoholic pilsner and black beers (coded respectively as PB, P0B and BB) were assayed and unmarinated samples cooked under similar conditions provided reference HAs levels. Two thermic (PhIP and 4,8-DiMeIQx) and three pyrolytic HAs (Trp-P-1, AαC, MeAαC) were quantified in unmarinated meat samples. Marinating meat in beer resulted in a significant decrease of PhIP, Trp-P-1 and AαC (p < 0.05). 4,8-DiMeIQx formation was inhibited only by BB marinade. No significant effect was observed on MeAαC formation. All beers reduced total HA formation in charcoal-grilled pork, black beer being the most efficient with a level of 90% inhibition. A strong positive correlation was observed between the inhibitory effect of beer on total HA formation and their antioxidant activity. Beer marinades mitigate the impact of consumption of well-done grilled pork meat reducing the formation of cooking carcinogens. PMID:25604939

  4. Steady-state response of a charcoal bed to radon in flowing air with water vapor

    SciTech Connect

    Blue, T.E.; Jarzemba, M.S.; Fentiman, A.W.

    1995-06-01

    Previously we have developed a mathematical model of radon adsorption in active air with water vapor on small U.S. Environmental Protection Agency charcoal canisters that are used for environmental measurements of radon. The purpose of this paper is to extend this mathematical model to describe the adsorption of radon by large charcoal beds with radon-laden air flowing through them. The resulting model equations are solved analytically to predict the steady-state adsorption of radon by such beds. 14 refs., 3 figs.

  5. High-speed ultrashort pulse fiber ring laser using charcoal nanoparticles.

    PubMed

    Li, Wenbo; Hu, Hongyu; Zhang, Xiang; Zhao, Shuai; Fu, Kan; Dutta, Niloy K

    2016-03-20

    A mode-locked erbium-doped fiber ring laser that is easy to set up is proposed and experimentally demonstrated to generate a high-repetition-rate optical pulse train with an ultrashort pulse width. The laser combines a rational harmonic mode-locking technique and charcoal nanoparticles as saturable absorbers. Compared to a solely active mode-locking scheme, the scheme with charcoal nanoparticles can remove the supermodes and narrow the pulse width by a factor of 0.57 at a repetition rate of 20 GHz. Numerical simulation of the laser performance is also provided, which shows good agreement with the experimental results. PMID:27140546

  6. The Political Is Personal: A Sample Activity.

    ERIC Educational Resources Information Center

    MacGregor, Molly Murphy

    1988-01-01

    Presents an oral history activity in which students discuss the relationship between historical events and their own lives, reflecting on their potential for influencing history. Points out that history flows in two directions, showing how events affect individual lives, and how individuals can impact on history. (LS)

  7. Emissions of air toxics from the production of charcoal in a simulated Missouri charcoal kiln

    SciTech Connect

    Lemieux, P.M.; Kariher, P.H.; Fairless, B.J.; Tapp, J.A.

    1998-11-01

    The paper gives results of experiments in a laboratory-scale charcoal kiln simulator to evaluate emissions of hazardous air pollutant from the production of charcoal in Missouri-type kilns. Fixed combustion gases were measured using continuous monitors. In addition, other pollutants, including methanol, volatile organic compounds, semivolatile organic compounds, and particle emission rates and size distributions were measured using various techniques. Emissions of all pollutants are reported in grams emitted per unit mass of initial wood converted to charcoal. Two burn conditions--slow and fast burn--were examined. High levels of methanol, benzene, and fine particulate were emitted from all tests. The estimated emissions from the fast burn conditions were significantly higher than those from the slow burn conditions.

  8. Neutron activation analysis for antimetabolites. [in food samples

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Determination of metal ion contaminants in food samples is studied. A weighed quantity of each sample was digested in a concentrated mixture of nitric, hydrochloric and perchloric acids to affect complete solution of the food products. The samples were diluted with water and the pH adjusted according to the specific analysis performed. The samples were analyzed by neutron activation analysis, polarography, and atomic absorption spectrophotometry. The solid food samples were also analyzed by neutron activation analysis for increased sensitivity and lower levels of detectability. The results are presented in tabular form.

  9. Charcoal as an alternative energy source. sub-project: briquetting of charcoal

    SciTech Connect

    Enstad, G.G.

    1982-02-02

    Charcoal briquettes have been studied both theoretically and experimentally. It appears most realistic to use binders in solution. Binders of this kind have been examined and the briquettes' mechanical properties measured. Most promising are borresperse, gum arabic, dynolex, and wood tar.

  10. BBQ charcoal combustion as an important source of trace metal exposure to humans.

    PubMed

    Susaya, Janice; Kim, Ki-Hyun; Ahn, Ji-Won; Jung, Myung-Chae; Kang, Chang-Hee

    2010-04-15

    To provide information about charcoal combustion as an important source of atmospheric trace metal pollution, 11 charcoal products were combusted and PM(10) filter samples were collected. The PM-bound metal elements were extracted by microwave acid digestion and analyzed by ICP-AES. The concentrations of trace metal elements ranged from a few to 10(5)ng m(-3) in the following order of magnitude: Zn>Pb>Mg>Ba>Cu>V>Cr>Co>Cd>Ni>Mn>Se>As. Emissions of most elements from charcoal combustion were high compared to other sources. In case of Cd, Co, and Ni, their concentrations exceeded the inhalation minimum risk levels (MRLs) of the United States Agency for Toxic Substances and Disease Registry (US-ATSDR) for chronic duration exposure by a factor of 30, 3.9, and 2.2, respectively. Likewise, Cd levels exceeded the US-ATSDR MRLs for acute-duration exposure by a factor of 10, while those of Pb and Cd exceeded air quality guideline (AQG) of the World Health Organization (WHO) by a factor of 29 and 59, respectively. Mn levels also exceeded the United States Environmental Protection Agency (US EPA) Reference Air Concentrations (RfCs) by a factor of 2.7. This study shows that barbecue charcoal combustion can be an important source of trace metal emissions to the atmosphere with potential health risks. PMID:20031319

  11. Assessing the mineralisation of charcoal carbon in temperate soils

    NASA Astrophysics Data System (ADS)

    Ascough, P. L.; Tilston, E.; Garnett, M.

    2012-04-01

    Charcoal is pyrolized biomass characterized by its high C content and environmental recalcitrance. Recently 'biochar' has emerged as a concept as a means of long-term C sequestration with a sequestration potential that is comparable with current global anthropogenic fossil fuel emissions (5.5-9.5 Pg C yr-1 and 5.4 Pg C yr-1, respectively). However, charcoal is not a permanent C sink and estimates of charcoal degradation rates vary from the decadal or centennial timescales, with soil residence times in the order of thousands of years. Possible mechanisms of charcoal degradation include biotically and abiotically-mediated transformation and mineralization processes, resulting in a range of products of varying recalcitrance, including CO2. In soil science the decomposition of organic matter is routinely estimated by measuring CO2 efflux, but a key obstacle for the quantification of charcoal-derived CO2 is the accurate and precise apportionment of C sources arising from slow decomposition rates. Moreover, the addition of charcoal to soil can promote decomposition of indigenous soil organic matter and the concomitant increase in CO2 production does not therefore necessarily demonstrate mineralization of the charcoal C. Radiocarbon (14C) offers significant benefits in this regard as a sensitive technique for C source apportionment. We used the 14C content of CO2 respired by a surface soil to quantify the rate of charcoal mineralization, thus demonstrating the efficacy and sensitivity of our 14C approach for estimating charcoal degradation. During incubation the variations in charcoal-derived C mineralization are consistent with the loss of more labile components in the charcoal with a maximum of 2.1% of the evolved CO2-C being attributable to mineralisation of charcoal C. Extrapolation to an annual basis suggests that the loss rate of charcoal C is <1%, supporting the view that rates of charcoal C respiration are slow in temperate woodland soil. Implications for

  12. Soil quality in a cropland soil treated with wood ash containing charcoal

    NASA Astrophysics Data System (ADS)

    Omil, Beatriz; Balboa, Miguel A.; Fonturbel, M. Teresa; Gartzia-Bengoetxea, Nahia; Arias-González, Ander; Vega, Jose A.; Merino, Agustin

    2014-05-01

    The strategy of the European Union "Europe 2020" states that by 2020, 20% of final energy consumption must come from renewables. In this scenario, there is an increasing use of biomass utilization for energy production. Indeed, it is expected that the production of wood-ash will increase in coming years. Wood ash, a mixture of ash and charcoal, generated as a by-product of biomass combustion in power plants, can be applied to soil to improve the soil quality and crop production. Since the residue contains significant content of charcoal, the application of mixed wood ash may also improve the SOM content and soil quality in the long term, in soils degraded as a consequence of intensive management. The objective of this study was asses the changes in SOM quality and soil properties in a degraded soils treated with wood ash containing charcoal. The study was carried out in a field devoted to cereal crops during the last decades. The soil was acidic (pH 4.5) with a low SOC content (3 %) and fine texture. The experiment was based on a randomised block design with four replicates. Each block included the following four treatments: Control, 16 Mg fly wood ash ha-1, 16 Mg mixed wood ash ha-1 (16 Mg) and 32 Mg mixed wood ash ha-1 (32 Mg). The application was carried out once. The ash used in the study was obtained from a thermal power plant and was mainly derived from the combustion of Pinus radiata bark and branches. The wood ash is highly alkaline (pH= 10), contains 10 % of highly condensed black carbon (atomic H/C ratio < 0.5 and T50 en DSC= 500 ºC). The evolution of SOM properties were monitored over three years by solid state 13C CPMAS NMR and Differential Scanning Calorimetry (DSC). These techniques were applied in bulk samples and aggregates of different sizes. The changes in microbial activity were studied by analysis of microbial biomass C and basal respiration. The soil bacterial community was studied by the Biolog method. Several physical properties, such soil

  13. Open charcoal chamber method for mass measurements of radon exhalation rate from soil surface.

    PubMed

    Tsapalov, Andrey; Kovler, Konstantin; Miklyaev, Peter

    2016-08-01

    Radon exhalation rate from the soil surface can serve as an important criterion in the evaluation of radon hazard of the land. Recently published international standard ISO 11665-7 (2012) is based on the accumulation of radon gas in a closed container. At the same time since 1998 in Russia, as a part of engineering and environmental studies for the construction, radon flux measurements are made using an open charcoal chamber for a sampling duration of 3-5 h. This method has a well-defined metrological justification and was tested in both favorable and unfavorable conditions. The article describes the characteristics of the method, as well as the means of sampling and measurement of the activity of radon absorbed. The results of the metrological study suggest that regardless of the sampling conditions (weather, the mechanism and rate of radon transport in the soil, soil properties and conditions), uncertainty of method does not exceed 20%, while the combined standard uncertainty of radon exhalation rate measured from the soil surface does not exceed 30%. The results of the daily measurements of radon exhalation rate from the soil surface at the experimental site during one year are reported. PMID:27132250

  14. SNS Sample Activation Calculator Flux Recommendations and Validation

    SciTech Connect

    McClanahan, Tucker C.; Gallmeier, Franz X.; Iverson, Erik B.; Lu, Wei

    2015-02-01

    The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) uses the Sample Activation Calculator (SAC) to calculate the activation of a sample after the sample has been exposed to the neutron beam in one of the SNS beamlines. The SAC webpage takes user inputs (choice of beamline, the mass, composition and area of the sample, irradiation time, decay time, etc.) and calculates the activation for the sample. In recent years, the SAC has been incorporated into the user proposal and sample handling process, and instrument teams and users have noticed discrepancies in the predicted activation of their samples. The Neutronics Analysis Team validated SAC by performing measurements on select beamlines and confirmed the discrepancies seen by the instrument teams and users. The conclusions were that the discrepancies were a result of a combination of faulty neutron flux spectra for the instruments, improper inputs supplied by SAC (1.12), and a mishandling of cross section data in the Sample Activation Program for Easy Use (SAPEU) (1.1.2). This report focuses on the conclusion that the SAPEU (1.1.2) beamline neutron flux spectra have errors and are a significant contributor to the activation discrepancies. The results of the analysis of the SAPEU (1.1.2) flux spectra for all beamlines will be discussed in detail. The recommendations for the implementation of improved neutron flux spectra in SAPEU (1.1.3) are also discussed.

  15. Evaluation of soybean genotypes for resistance to charcoal rot

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Charcoal rot caused by Macrophomina phaseolina causes more yield loss in soybean than most other diseases in the southern U.S.A. There are no commercial genotypes marketed as resistant to charcoal rot of soybean. Reactions of 27 maturity group (MG) III, 29 Early MG IV, 34 Late MG IV, and 59 MG V gen...

  16. Characterization of charcoals for helium cryopumping in fusion devices

    NASA Astrophysics Data System (ADS)

    Sedgley, D. W.; Tobin, A. G.; Batzer, T. H.; Call, W. R.

    1987-07-01

    The capability of charcoal as a sorbent for helium at cryogenic temperatures depends upon charcoal characteristics that are not well understood. Previous work by the authors has indicated that the charcoals- pumping capability for helium depends as much on their source as on their particle size distributions. To develop a correlation between the physical characteristics of charcoal and helium pumping performance, different charcoals based on wood, coal, coconut, and a petroleum by-product were obtained from commercial sources. They were bonded to an aluminum substrate, and cooled to liquid-helium temperatures in a vacuum chamber. The helium pumping speed at constant throughput versus quantity of helium absorbed was measured for each charcoal grade. Porosimetry measurements on each charcoal grade using nitrogen as the sorbent gas were made that included total surface area, adsorption and desorption isotherms, and pore area and pore volume distributions. Significant differences in helium pumping performance and in pore size distribution were observed. Comparisons are made between helium pumping performance and charcoal characteristics and a possible correlation is identified.

  17. Characterization of charcoals for helium cryopumping in fusion devices

    SciTech Connect

    Sedgley, D.W.; Tobin, A.G.; Batzer, T.H.; Call, W.R.

    1987-07-01

    The capability of charcoal as a sorbent for helium at cryogenic temperatures depends upon charcoal characteristics that are not well understood. Previous work by the authors has indicated that the charcoals' pumping capability for helium depends as much on their source as on their particle size distributions. To develop a correlation between the physical characteristics of charcoal and helium pumping performance, different charcoals based on wood, coal, coconut, and a petroleum by-product were obtained from commercial sources. They were bonded to an aluminum substrate, and cooled to liquid-helium temperatures in a vacuum chamber. The helium pumping speed at constant throughput versus quantity of helium absorbed was measured for each charcoal grade. Porosimetry measurements on each charcoal grade using nitrogen as the sorbent gas were made that included total surface area, adsorption and desorption isotherms, and pore area and pore volume distributions. Significant differences in helium pumping performance and in pore size distribution were observed. Comparisons are made between helium pumping performance and charcoal characteristics and a possible correlation is identified.

  18. Resistance to charcoal rot identified in ancestral soybean germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Charcoal rot, caused by the fungal pathogen Macrophomina phaseolina, is an economically important disease on soybean and other crops including maize, sorghum, and sunflowers. Without effective cultural or chemical options to control charcoal rot in soybean, finding sources of genetic resistance is o...

  19. EMISSIONS OF AIR TOXICS FROM A SIMULATED CHARCOAL KILN

    EPA Science Inventory

    The report gives results of experiments in a laboratory-scale charcoal kiln simulator to evaluate emissions of hazardous air pollutants from the production of charcoal in Missouri-type kilns. Fixed combustion gases were measured using continuous monitors. In Addition, other pollu...

  20. Superfund record of decision amendment (EPA Region 4): Wrigley Charcoal Superfund Site, Hickman County, Wrigley, TN, February 2, 1995

    SciTech Connect

    1995-03-01

    This decision document presents the selected Interim Remedial Action (IRA) for the Wrigley Charcoal Site, in Wrigley, Hickman County, Tennessee. The U.S. EPA has modified a wide variety of items that require immediate response action for the first step of cleanup activities to be taken at the Wrigley Charcoal Site. The major goal of these cleanup activities is to address the most serious threats at the Wrigley Charcoal Site by removing contaminated media from the Primary Site flood plain, remediating wastes at the Storage Basin, and through limited access restrictions at the Primary Site and the Storage Basin. The cleanup activities as presented in this IRA Record of Decision (ROD) Amendment will achieve significant risk reduction and will prepare the Site for future remedial activities.

  1. An equilibrium-based model for measuring environmental radon using charcoal canisters.

    PubMed

    Lehnert, A L; Kearfott, K J

    2010-08-01

    Radon in indoor air is often measured using canisters of activated charcoal that function by adsorbing radon gas. The use of a diffusion barrier charcoal canister (DBCC) minimizes the effects of environmental humidity and extends the useful exposure time by several days. Many DBCC protocols model charcoal canisters as simple integrating detectors, which introduces errors due to the fact that radon uptake changes over the exposure period. Errors are compensated for by calculating a calibration factor that is nonlinear with respect to exposure time. This study involves the development and testing of an equilibrium-based model and corresponding measurement protocol that treats the charcoal canisters as a system coming into equilibrium with the surrounding radon environment. This model applies to both constant and temporally varying radon concentration situations, which was essential, as efforts are currently underway using a temporally varying radon chamber. It was found that the DBCCs equilibrate following the relationship E = (1 - e) where E is a measure of how close the DBCC is to equilibrium, t is exposure time, and q is the equilibration constant. This equilibration constant was empirically determined to be 0.019 h. The proposed model was tested in a blind test as well as compared with the currently accepted U.S. Environmental Protection Agency (U.S. EPA) model. Comparisons between the two methods showed a slight decrease in measurement error when using the equilibrium-based method as compared to the U.S. EPA method. PMID:20622564

  2. Carbon sequestration and fertility after centennial time scale incorporation of charcoal into soil

    NASA Astrophysics Data System (ADS)

    Criscuoli, Irene; Alberti, Giorgio; Baronti, Silvia; Favilli, Filippo; Martinez, Cristina; Calzolari, Costanza; Pusceddu, Emanuela; Rumpel, Cornelia; Viola, Roberto; Miglietta, Franco

    2014-05-01

    The addition of pyrogenic carbon (C) in the soil is considered a sustainable strategy to achieve direct C sequestration and potential reduction of non-CO2 greenhouse gas emissions. In this paper, we investigated the long term effects of charcoal addition on C sequestration and soil chemico-physical properties by studying a series of abandoned charcoal hearths in the Eastern Alps established in the XIX century. This natural setting can be seen as an analogue of a deliberate experiment with replications. Carbon sequestration was assessed indirectly by comparing the amount of C present in the hearths with the estimated amount of charcoal that was left on the soil after the carbonization. Approximately 80% of the C originally added to the soil via charcoal can still be found today, thus supporting the view that charcoal incorporation is an effective way to sequester atmospheric CO2. We also observed an improvement in the physical properties (hydrophobicity and bulk density) of charcoal hearth soils and an accumulation of nutrients compared to the adjacent soil without charcoal. Then, we focused on the morphological and physical characterization of several fragments, using scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray fluorescence (XRF). Such study enabled the identification of peculiar morphological features of tracheids, which were tentatively associated to a differential oxidation of the structures that were created during carbonization from lignine and cellulose. In order to assess the effect of soil-aging we compared the old-biochar with a modern one obtained from the same feedstock and with similar carbonization process. XRD and XRF analysis were performed on both old and modern biochar, in order to study the multiphase crystalline structure and chemical elements found. We observed mineralization and a fossilization of old biochar samples respect to the modern ones, with accumulation of several mineral oxides and a substantial presence of

  3. Radiocarbon dating of charcoal and bone collagen associated with early pottery at Yuchanyan Cave, Hunan Province, China

    PubMed Central

    Boaretto, Elisabetta; Wu, Xiaohong; Yuan, Jiarong; Bar-Yosef, Ofer; Chu, Vikki; Pan, Yan; Liu, Kexin; Cohen, David; Jiao, Tianlong; Li, Shuicheng; Gu, Haibin; Goldberg, Paul; Weiner, Steve

    2009-01-01

    Yuchanyan Cave in Daoxian County, Hunan Province (People's Republic of China), yielded fragmentary remains of 2 or more ceramic vessels, in addition to large amounts of ash, a rich animal bone assemblage, cobble and flake artifacts, bone tools, and shell tools. The artifacts indicate that the cave was a Late Paleolithic foragers' camp. Here we report on the radiocarbon ages of the sediments based on analyses of charcoal and bone collagen. The best-preserved charcoal and bone samples were identified by prescreening in the field and laboratory. The dates range from around 21,000 to 13,800 cal BP. We show that the age of the ancient pottery ranges between 18,300 and 15,430 cal BP. Charcoal and bone collagen samples located above and below one of the fragments produced dates of around 18,000. These ceramic potsherds therefore provide some of the earliest evidence for pottery making in China. PMID:19487667

  4. Radiocarbon dating of charcoal and bone collagen associated with early pottery at Yuchanyan Cave, Hunan Province, China.

    PubMed

    Boaretto, Elisabetta; Wu, Xiaohong; Yuan, Jiarong; Bar-Yosef, Ofer; Chu, Vikki; Pan, Yan; Liu, Kexin; Cohen, David; Jiao, Tianlong; Li, Shuicheng; Gu, Haibin; Goldberg, Paul; Weiner, Steve

    2009-06-16

    Yuchanyan Cave in Daoxian County, Hunan Province (People's Republic of China), yielded fragmentary remains of 2 or more ceramic vessels, in addition to large amounts of ash, a rich animal bone assemblage, cobble and flake artifacts, bone tools, and shell tools. The artifacts indicate that the cave was a Late Paleolithic foragers' camp. Here we report on the radiocarbon ages of the sediments based on analyses of charcoal and bone collagen. The best-preserved charcoal and bone samples were identified by prescreening in the field and laboratory. The dates range from around 21,000 to 13,800 cal BP. We show that the age of the ancient pottery ranges between 18,300 and 15,430 cal BP. Charcoal and bone collagen samples located above and below one of the fragments produced dates of around 18,000. These ceramic potsherds therefore provide some of the earliest evidence for pottery making in China. PMID:19487667

  5. Criticality safety study of the MSRE auxiliary charcoal bed

    SciTech Connect

    Hollenbach, D.F.; Hopper, C.M.

    1996-09-01

    The Molten Salt Reactor Experiment (MSRE) was operated from June 1965 to December 1969. The objective of the experiment was to investigate the practicality of developing a power reactor consisting of a graphite lattice with circulating molten uranium salt as fuel for application in central power stations. When the experiment was terminated in 1969, approximately 4710 kg of salt containing approximately 36.3 kg of uranium, 675 g of plutonium, and various fission products were transferred to two fuel drain tanks (FDTs). The almost 30.5 kg of Uranium 233 in the salt is the primary fissile constituent, but about 0.93 kg of Uranium 235 is also present. In April 1994, a gas sample from the MSRE off-gas system (OGS) indicated that uranium had migrated from the FDTs into the OGS. Further investigation revealed a likely accumulation of approximately 2.6 kg of uranium in the auxiliary charcoal bed (ACB), which is located in the concrete-lined charcoal bed cell (CBC) below ground level outside the MSRE building. The nuclear criticality safety (NCS) situation was further complicated by the CBC being filled with water up to the overflow pipe, which completely submerged the ACB. Thus there was not only an increased risk of criticality because of water reflection in the ACB, but also because of potential moderation in the ACB in case of water inleakage. Leakage into the ACB would result in a direct path for water between the CBC and the OGS or FDTs, thus increasing the risk of criticality in these areas. When uranium was discovered in the ACB, a number of steps, detailed in this report, were immediately taken to try to understand and ameliorate the situation. After all the actions were completed, a validation of the results obtained for the ACB was performed.

  6. COMPARISON OF SAMPLING METHODS FOR SEMI-VOLATILE ORGANIC CARBON ASSOCIATED WITH PM 2.5

    EPA Science Inventory

    This study evaluates the influence of denuder sampling methods and filter collection media on the measurement of semi-volatile organic carbon (SVOC) associated with PM2.5. Two types of collection media, charcoal (activated carbon) and XAD, were used both in diffusion denuders ...

  7. Mechanisms of charcoal degradation during its initial stages of decomposition

    NASA Astrophysics Data System (ADS)

    Singh, Nimisha; Abiven, Samuel; Schmidt, Michael W. I.

    2010-05-01

    Future climatic changes might result in an increased potential for wildfires, whereby incorporation of charred biomass into soil would increase. The incomplete combustion of biomass results in the production of a chemically heterogeneous class of highly condensed compounds known as pyrogenic C (PyC), which is generally considered resistant to microbial degradation. Recently, studies based on short-term laboratory incubations with soil have indicated that PyC can also eventually degrade (Baldock and Smernik, 2002; Hamer et al., 2004) and it is now widely accepted that a significant quantity of these resistant fraction of soil must have undergone degradation in terrestrial environments. Charcoal has been shown to decompose faster in the initial stages (first 2-3 months) and stabilize later (Kuzyakov et al., 2009). However, studies describing charcoal transformation processes remain scarce. The different potential degradation mechanisms have not yet been studied in combination, and therefore the relative importance for PyC degradation has not been evaluated. We are conducting an incubation experiment to study the biological, chemical and physical degradation/stabilization processes of PyC in soil under controlled conditions. We use Pinus ponderosa 13C/15N labeled (13C: 800 per mil, 15N: 4.2 atom %) wood and charcoal (pyrolysed at 450 °C under N2 atmosphere). We incubate soil from Lägeren forest (Wettingen, Switzerland) with three kind of organic inputs, labeled wood, char and no littler control. The decomposition rates would be estimated based on 13C of CO2 entrapped in NaOH. Time course destructive sampling would be done during the study. Lyophilized soil subsamples will be used for analysis of the amount of 13C incorporation in the microbial biomass using fumigation extraction method and phospholipids fatty acid analysis (PLFA). The remaining PyC in the soil would be characterized for the changes in its chemistry at the molecular level using Benzenepolycarboxlic

  8. Identifying past fire regimes throughout the Holocene in Ireland using new and established methods of charcoal analysis

    NASA Astrophysics Data System (ADS)

    Hawthorne, Donna; Mitchell, Fraser J. G.

    2016-04-01

    Globally, in recent years there has been an increase in the scale, intensity and level of destruction caused by wildfires. This can be seen in Ireland where significant changes in vegetation, land use, agriculture and policy, have promoted an increase in fires in the Irish landscape. This study looks at wildfire throughout the Holocene and draws on lacustrine charcoal records from seven study sites spread across Ireland, to reconstruct the past fire regimes recorded at each site. This work utilises new and accepted methods of fire history reconstruction to provide a recommended analytical procedure for statistical charcoal analysis. Digital charcoal counting was used and fire regime reconstructions carried out via the CharAnalysis programme. To verify this record new techniques are employed; an Ensemble-Member strategy to remove the objectivity associated with parameter selection, a Signal to Noise Index to determine if the charcoal record is appropriate for peak detection, and a charcoal peak screening procedure to validate the identified fire events based on bootstrapped samples. This analysis represents the first study of its kind in Ireland, examining the past record of fire on a multi-site and paleoecological timescale, and will provide a baseline level of data which can be built on in the future when the frequency and intensity of fire is predicted to increase.

  9. Neutron activation analysis of certified samples by the absolute method

    NASA Astrophysics Data System (ADS)

    Kadem, F.; Belouadah, N.; Idiri, Z.

    2015-07-01

    The nuclear reactions analysis technique is mainly based on the relative method or the use of activation cross sections. In order to validate nuclear data for the calculated cross section evaluated from systematic studies, we used the neutron activation analysis technique (NAA) to determine the various constituent concentrations of certified samples for animal blood, milk and hay. In this analysis, the absolute method is used. The neutron activation technique involves irradiating the sample and subsequently performing a measurement of the activity of the sample. The fundamental equation of the activation connects several physical parameters including the cross section that is essential for the quantitative determination of the different elements composing the sample without resorting to the use of standard sample. Called the absolute method, it allows a measurement as accurate as the relative method. The results obtained by the absolute method showed that the values are as precise as the relative method requiring the use of standard sample for each element to be quantified.

  10. Tubular bamboo charcoal for anode in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Zhang, Jun; Li, Jun; Ye, Dingding; Zhu, Xun; Liao, Qiang; Zhang, Biao

    2014-12-01

    The anode material plays a significant role in determining the performance of microbial fuel cells (MFCs). In this study, the bamboo charcoal tube is proposed as a novel anode substrate by carbonizing the natural bamboo. Its surface functional groups, biocompatibility and internal resistance are thoroughly investigated. Performance of the MFCs with a conventional graphite tube anode and a bamboo charcoal tube anode is also compared. The results indicate that the tubular bamboo charcoal anode exhibits advantages over the graphite tube anode in terms of rougher surface, superior biocompatibility and smaller total internal resistance. Moreover, the X-ray photoelectron spectroscopy (XPS) analysis for the bamboo charcoal reveals that the introduced C-N bonds facilitate the electron transfer between the biofilm and electrodes. As a result, the MFC with a bamboo charcoal tube anode achieves a 50% improvement in the maximum power density over the graphite tube case. Furthermore, scale-up of the bamboo charcoal tube anode is demonstrated by employing a bundle of tubular bamboo charcoal to reach higher power output.

  11. Six centuries of anthropogenic forest change on a Polynesian high island: Archaeological charcoal records from the Marquesas Islands

    NASA Astrophysics Data System (ADS)

    Huebert, Jennifer M.; Allen, Melinda S.

    2016-04-01

    It is widely recognised that Polynesian settlers developed central Pacific islands into productive economic landscapes, but the character and tempo of these transformations are poorly understood. Archaeological wood charcoal assemblages are uniquely suited to inform on landscape change, especially when the principal food crops were arboreal. We use a large archaeological charcoal collection, drawn from numerous geographically and functionally varied contexts, to develop a multi-scalar vegetation history of Marquesas Islands' lowland forests. Our aims were to: 1) reveal historical patterns of plant biogeography, including introductions by Polynesian settlers; 2) detail the nature and timing of anthropogenic impacts on native Marquesan forests; and 3) track the emergence of economically productive arboreal landscapes. A collection of 6510 fragments identified to 59 taxa inform on a ∼600-year sequence of human activities. The earliest samples indicate rich forests were encountered by human colonists, comprised of a mix of dicotyledonous hardwood species and woody monocots. These included members of two now-extinct Sapotaceae genera, Planchonella and cf. Sideroxylon, along with Allophylus, a Sapindaceae apparently extirpated from Nuku Hiva. Two important coastal trees, Calophyllum inophyllum and Thespesia populnea, also appear to be indigenous. Polynesian impacts were rapid and widespread, irrevocably altering the indigenous vegetation and disrupting native ecosystems. Samples from later occupations document on-going modifications to lowland vegetation communities. This included inter-valley variability in the timing of transformations and the development of mosaic formations, comprised of native forest interspersed with areas of cultivation and habitation. By 1650 CE, low and mid-elevation vegetation was extensively remodelled, as anthropogenic forests of Artocarpus altilis (breadfruit), Inocarpus fagifer (Tahitian chestnut), and other economic species became widely

  12. Gastric decontamination performed 5 min after the ingestion of temazepam, verapamil and moclobemide: charcoal is superior to lavage

    PubMed Central

    Lapatto-reiniluoto, O; Kivistö, K T; Neuvonen, P J

    2000-01-01

    Aims The aim was to study the efficacy of gastric lavage and activated charcoal in preventing the absorption of temazepam, verapamil and moclobemide when gastric decontamination was performed immediately after ingestion of the drugs. Methods Nine healthy volunteers took part in a randomized cross-over study with three phases. The subjects were administered single oral doses of 10 mg temazepam, 80 mg verapamil and 150 mg moclobemide. Five minutes later, they were assigned to one of the following treatments: 200 ml water (control), 25 g activated charcoal as a suspension in 200 ml water or gastric lavage. Plasma concentrations and the cumulative excretion into urine of the three drugs were determined up to 24 h. Results The mean AUC(0,24 h) of temazepam, verapamil and moclobemide was reduced by 95.2% (P < 0.01), 92.8% (P < 0.01) and 99.7% (P < 0.01), respectively, by activated charcoal compared with control. Gastric lavage did not reduce significantly the AUC(0,24 h) of these drugs. The 24 h cumulative excretion of temazepam, verapamil and moclobemide into urine was reduced significantly (P < 0.05) by charcoal but not by gastric lavage. Charcoal reduced the AUC(0,24 h), Cmax and urinary excretion of all three drugs significantly more than lavage. Conclusions Activated charcoal is very effective and gastric lavage can be rather ineffective in preventing the absorption of temazepam, verapamil and moclobemide when the treatment is given very rapidly after ingestion of the drugs, before tablet disintegration has occurred. PMID:10718784

  13. Volatile compounds and odor preferences of ground beef added with garlic and red wine, and irradiated with charcoal pack

    NASA Astrophysics Data System (ADS)

    Lee, Kyung Haeng; Yun, Hyejeong; Lee, Ju Woon; Ahn, Dong Uk; Lee, Eun Joo; Jo, Cheorun

    2012-08-01

    Irradiation is the most efficient non-thermal technology for improving hygienic quality and extending the shelf-life of food products. One of the adverse effects of food irradiation, however, is off-flavor production, which significantly affects the sensory preferences for certain foods. In this study, garlic (5%, w/w) and red wine (1:1, w/w) were added to ground beef to increase the radiation sensitivity of pathogens and improve meat odor/flavor. Samples were irradiated at 0 or 5 kGy in the presence of charcoal pack. SPME-GC-MS analysis was performed to measure the changes in the volatile compounds and sensory characteristics of the samples. The amount of total volatile compounds produced from ground beef was greater when the sample was irradiated. When garlic and red wine were added to the ground beef, the amount of volatile compounds significantly increased, and the amount of volatile compounds increased even further after irradiation. However, when the samples were irradiated with charcoal pack, the amount of volatile compounds decreased significantly. Sensory evaluation indicated that charcoal pack significantly increased the odor preferences for both irradiated and non-irradiated ground beef added with garlic. These results indicated that addition of charcoal pack to ground beef could reduce off-odor problems induced by irradiation, and this effect was consistent even when certain additives such as garlic and red wine were added.

  14. Reduction of the polycyclic aromatic hydrocarbon (PAH) content of charcoal smoke during grilling by charcoal preparation using high carbonisation and a preheating step.

    PubMed

    Chaemsai, Suriyapong; Kunanopparat, Thiranan; Srichumpuang, Jidapa; Nopharatana, Montira; Tangduangdee, Chairath; Siriwattanayotin, Suwit

    2016-01-01

    Charcoal-grilling may lead to contamination of food with carcinogenic polycyclic aromatic hydrocarbons (PAHs) during the grilling process. The objective of this work was to determine the effect of charcoal preparation on 16 USEPA priority PAHs in the smoke produced during the grilling process. Firstly, mangrove charcoal was prepared at carbonisation temperatures of 500, 750 and 1000 °C. The charcoal were then preheated by burning at 650 °C. This preheating step is usually used to prepare hot charcoal for the grilling process in the food industry. In this study, charcoal was preheated at different burning times at 5, 20 min and 5 h, at which time partial and whole charcoal glowed, and charcoal was completely burnt, respectively. Finally, PAHs in the smoke were collected and determined by GC/MS. The result showed that charcoal prepared at a carbonisation temperature of 500 °C had higher levels of PAHs released into the smoke. In contrast, charcoal produced at 750 and 1000 °C had lower PAHs released for all burning times. In addition, PAHs released for 5, 20 min and 5 h of burning time were about 19.9, 1.2 and 0.7 µg g(-1) dry charcoal for charcoal produced at 500 °C, and about 0.9-1.4, 0.8-1.2 and 0.15-0.3 µg g(-1) dry charcoal for charcoal produced at 750 and 1000 °C, respectively. Therefore, this research suggests that food grilled using charcoal carbonised at a high temperature of about 750 °C presents a lower risk of PAH contamination. In addition, in the preheating step, whole charcoal should fully glow in order to reduce the PAH content in charcoal before grilling. PMID:26785749

  15. Improved mesh based photon sampling techniques for neutron activation analysis

    SciTech Connect

    Relson, E.; Wilson, P. P. H.; Biondo, E. D.

    2013-07-01

    The design of fusion power systems requires analysis of neutron activation of large, complex volumes, and the resulting particles emitted from these volumes. Structured mesh-based discretization of these problems allows for improved modeling in these activation analysis problems. Finer discretization of these problems results in large computational costs, which drives the investigation of more efficient methods. Within an ad hoc subroutine of the Monte Carlo transport code MCNP, we implement sampling of voxels and photon energies for volumetric sources using the alias method. The alias method enables efficient sampling of a discrete probability distribution, and operates in 0(1) time, whereas the simpler direct discrete method requires 0(log(n)) time. By using the alias method, voxel sampling becomes a viable alternative to sampling space with the 0(1) approach of uniformly sampling the problem volume. Additionally, with voxel sampling it is straightforward to introduce biasing of volumetric sources, and we implement this biasing of voxels as an additional variance reduction technique that can be applied. We verify our implementation and compare the alias method, with and without biasing, to direct discrete sampling of voxels, and to uniform sampling. We study the behavior of source biasing in a second set of tests and find trends between improvements and source shape, material, and material density. Overall, however, the magnitude of improvements from source biasing appears to be limited. Future work will benefit from the implementation of efficient voxel sampling - particularly with conformal unstructured meshes where the uniform sampling approach cannot be applied. (authors)

  16. 24. Photocopy of photograph. VIEW OF CHARCOAL KILNS AND IRON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. Photocopy of photograph. VIEW OF CHARCOAL KILNS AND IRON PLANT FROM SOUTH END OF BEACH, probably 1901. (From the Robert Teagle Private Collection, Port Townsend, WA) - Irondale Iron & Steel Plant, Port Townsend, Jefferson County, WA

  17. INTERIOR DETAIL, STOVE. SMALL CHARCOAL FIRES WERE LIT IN THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR DETAIL, STOVE. SMALL CHARCOAL FIRES WERE LIT IN THE DEPRESSIONS, WHICH WERE COVERED WITH IRON GRATES TO SUSPEND POTS OVER THE HEAT SOURCE - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

  18. COMPARISON OF SAMPLING METHODS FOR SEMI-VOLATILE ORGANIC CARBON (SVOC) ASSOCIATED WITH PM 2.5

    EPA Science Inventory

    This study evaluates the influence of denuder sampling methods and filter collection media on the measurement of semi-volatile organic carbon (SVOC) associated with PM2.5. Two types of collection media, charcoal (activated carbon) and XAD, were used both in diffusion denuders ...

  19. Polycyclic aromatic hydrocarbons from wood pyrolyis in charcoal production furnaces.

    PubMed

    Barbosa, Joyce Mara dos Santos; Ré-Poppi, Nilva; Santiago-Silva, Mary

    2006-07-01

    Polycyclic aromatic hydrocarbons (PAH) were measured in smoke samples from wood carbonization during charcoal production, in both particulate matter (PM) and gaseous phases. Samples were acquired using a medium-volume air sampler at 1.5 m distance from the furnace. Particle-bound PAH were collected on Fluoropore polytetrafluoroethylene filters and gas-phase PAH were collected into sorbent tubes with XAD-2 resin. PAH were extracted with dichloromethane-methanol and analyzed using gas chromatography-mass spectrometry. The results showed total emission from the furnace of 26 microg/m3 for the 16 PAH and 2.8 microg/m3 for the 10 genotoxic PAH (from fluoranthene to benzo[g,h,i]perylene). High emission of 16 PAH in the first 8 h of wood carbonization was detected (64 microg/m3; 56% of the total emission). Associated with PM, 11% of the total emission of 16 PAH (in both phases) and 60% of 10 genotoxic PAH were found. Relative ratios (for example, [Phe]/[Phe]+[Ant]) for the PAH of the same molecular weight were obtained and compared with the published data. The concentrations of benzo[a]pyrene equivalent (BaP(eq)) were estimated using the list of toxic equivalent factors suggested by . The values of 0.30 and 0.06 mg/m3 were obtained for the total concentrations of BaP(eq) in PM and gaseous phase, respectively. PMID:16499903

  20. Effect of Catnip Charcoal on the In Vivo Pharmacokinetics of the Main Alkaloids of Rhizoma Coptidis.

    PubMed

    He, Yanfei; Chen, Siyu; Yu, Hai; Zhu, Long; Liu, Yayun; Han, Chunyang; Liu, Cuiyan

    2016-01-01

    This study aims to explore the effect of catnip Nepeta cataria (CNC) charcoal on the pharmacokinetics of the main alkaloids of Rhizoma Coptidis in vivo. Twenty-four rabbits were randomly divided into four groups and given oral administration of an aqueous extract of Rhizoma Coptidis (RCAE), RCAE plus CNC, RCAE plus activated carbon (AC), or distilled water, respectively. Plasma samples were collected after administration. The concentrations of berberine, coptisine, palmatine, and epiberberine in plasma were measured by high-performance liquid chromatography (HPLC). The pharmacokinetics data were calculated using pharmacokinetic DAS 2.0 software. The results showed that the area under the concentration-time curve (AUC) of berberine increased, while the AUC of coptisine, palmatine, and epiberberine decreased in the rabbits that received RCAE plus CNC. Meanwhile, the AUC of berberine, coptisine, palmatine, and epiberberine decreased in the group given RCAE plus AC. The difference of main pharmacokinetics parameters among the four groups was significant (P < 0.05). This study showed that CNC improved the bioavailability of berberine in comparison to AC and prolonged its release in comparison to RCAE alone. However, it decreased the bioavailability of coptisine, palmatine, and epiberberine. In comparison, AC uniformly declined the bioavailability of berberine, coptisine, palmatine, and epiberberine. PMID:27313645

  1. Effect of Catnip Charcoal on the In Vivo Pharmacokinetics of the Main Alkaloids of Rhizoma Coptidis

    PubMed Central

    He, Yanfei; Chen, Siyu; Yu, Hai; Zhu, Long; Liu, Yayun; Han, Chunyang; Liu, Cuiyan

    2016-01-01

    This study aims to explore the effect of catnip Nepeta cataria (CNC) charcoal on the pharmacokinetics of the main alkaloids of Rhizoma Coptidis in vivo. Twenty-four rabbits were randomly divided into four groups and given oral administration of an aqueous extract of Rhizoma Coptidis (RCAE), RCAE plus CNC, RCAE plus activated carbon (AC), or distilled water, respectively. Plasma samples were collected after administration. The concentrations of berberine, coptisine, palmatine, and epiberberine in plasma were measured by high-performance liquid chromatography (HPLC). The pharmacokinetics data were calculated using pharmacokinetic DAS 2.0 software. The results showed that the area under the concentration-time curve (AUC) of berberine increased, while the AUC of coptisine, palmatine, and epiberberine decreased in the rabbits that received RCAE plus CNC. Meanwhile, the AUC of berberine, coptisine, palmatine, and epiberberine decreased in the group given RCAE plus AC. The difference of main pharmacokinetics parameters among the four groups was significant (P < 0.05). This study showed that CNC improved the bioavailability of berberine in comparison to AC and prolonged its release in comparison to RCAE alone. However, it decreased the bioavailability of coptisine, palmatine, and epiberberine. In comparison, AC uniformly declined the bioavailability of berberine, coptisine, palmatine, and epiberberine. PMID:27313645

  2. Charcoal versus LPG grilling: A carbon-footprint comparison

    SciTech Connect

    Johnson, Eric

    2009-11-15

    Undoubtedly, grilling is popular. Britons fire up their barbeques some 60 million times a year, consuming many thousands of tonnes of fuel. In milder climates consumption is even higher, and in the developing world, charcoal continues to be an essential cooking fuel. So it is worth comparing the carbon footprints of the two major grill types, charcoal and LPG, and that was the purpose of the study this paper documents. Charcoal and LPG grill systems were defined, and their carbon footprints were calculated for a base case and for some plausible variations to that base case. In the base case, the charcoal grilling footprint of 998 kg CO{sub 2}e is almost three times as large as that for LPG grilling, 349 kg CO{sub 2}e. The relationship is robust under all plausible sensitivities. The overwhelming factors are that as a fuel, LPG is dramatically more efficient than charcoal in its production and considerably more efficient in cooking. Secondary factors are: use of firelighters, which LPG does not need; LPG's use of a heavier, more complicated grill; and LPG's use of cylinders that charcoal does not need.

  3. Interaction mechanisms of organic contaminants with burned straw ash charcoal.

    PubMed

    Huang, Wenhai; Chen, Baoliang

    2010-01-01

    Black carbons (e.g., charcoal) have a great impact on the transport of organic contaminants in soil and water because of its strong affinity and ubiquity in the environment. To further elucidate their interaction mechanism, sorption of polar (p-nitrotoluene, m-dinitrobenzene and nitrobenzene) and nonpolar (naphthalene) aromatic contaminants to burned straw ash charcoal under different de-ashed treatments were investigated. The sorption isotherms fitted well with Freundlich equation, and the Freundlich N values were all around 0.31-0.38, being independent of the sorbate properties and sorbent types. After sequential removal of ashes by acid treatments (HCl and HCl-HF), both adsorption and partition were enhanced due to the enrichment of charcoal component. The separated contribution of adsorption and partition to total sorption were quantified. The effective carbon content in ash charcoal functioned as adsorption sites, partition phases, and hybrid regions with adsorption and partition were conceptualized and calculated. The hybrid regions increased obviously after de-ashed treatment. The linear relationships of Freundlich N values with the charring-temperature of charcoal or biochar (the charred byproduct in biomass pyrolysis) were observed based on the current study and the cited publications which included 15 different temperatures (100-850 degrees C), 10 kinds of precursors of charcoal/biochar, and 10 organic sorbates. PMID:21235190

  4. A Sample Science Education Activity in Multicultural Environment

    ERIC Educational Resources Information Center

    Onder, Ismail; Kaplan, Aysun Oztuna; Besoluk, Senol

    2011-01-01

    In this study, a sample activity developed in the workshops called "Science education in multicultural environment" of the program "Integrative teaching in multicultural environment" was presented. Workshops about varied subjects were carried out by participants representing four countries and participants developed teaching materials by getting…

  5. Eastern Andean environmental and climate synthesis for the last 2000 years BP from terrestrial pollen and charcoal records of Patagonia

    NASA Astrophysics Data System (ADS)

    Sottile, G. D.; Echeverria, M. E.; Mancini, M. V.; Bianchi, M. M.; Marcos, M. A.; Bamonte, F. P.

    2015-06-01

    The Southern Hemisphere Westerly Winds (SWW) constitute an important zonal circulation system that dominates the dynamics of Southern Hemisphere mid-latitude climate. Little is known about climatic changes in the Southern South America in comparison to the Northern Hemisphere due to the low density of proxy records, and adequate chronology and sampling resolution to address environmental changes of the last 2000 years. Since 2009, new pollen and charcoal records from bog and lakes in northern and southern Patagonia at the east side of the Andes have been published with an adequate calibration of pollen assemblages related to modern vegetation and ecological behaviour. In this work we improve the chronological control of some eastern Andean previously published sequences and integrate pollen and charcoal dataset available east of the Andes to interpret possible environmental and SWW variability at centennial time scales. Through the analysis of modern and past hydric balance dynamics we compare these scenarios with other western Andean SWW sensitive proxy records for the last 2000 years. Due to the distinct precipitation regimes that exist between Northern (40-45° S) and Southern Patagonia (48-52° S) pollen sites locations, shifts on latitudinal and strength of the SWW results in large changes on hydric availability on forest and steppe communities. Therefore, we can interpret fossil pollen dataset as changes on paleohydric balance at every single site by the construction of paleohydric indices and comparison to charcoal records during the last 2000 cal yrs BP. Our composite pollen-based Northern and Southern Patagonia indices can be interpreted as changes in latitudinal variation and intensity of the SWW respectively. Dataset integration suggest poleward SWW between 2000 and 750 cal yrs BP and northward-weaker SWW during the Little Ice Age (750-200 cal yrs BP). These SWW variations are synchronous to Patagonian fire activity major shifts. We found an in phase

  6. Charcoal agar, a new growth medium for the fish disease bacterium Renibacterium salmoninarum.

    PubMed Central

    Daly, J G; Stevenson, R M

    1985-01-01

    Charcoal is an effective replacement for serum in media for the isolation and culture of Renibacterium salmoninarum, the causative agent of bacterial kidney disease in salmonid fish. The medium, KDM-C, contains 10 g of peptone, 0.5 g of yeast extract, 1 g of L-cysteine hydrochloride, 1 g of activated charcoal, and 15 g of agar per liter and is adjusted to pH 6.8 with NaOH before autoclaving. Eight strains of R. salmoninarum grew from dilute inocula as well on KDM-C as on a standard serum-containing medium (KDM-2). The medium was effective for both primary isolations from fish and repeated transfers and has potential value for antigen preparation and physiological studies. Images PMID:4083882

  7. Performance testing of the NIOSH charcoal tube technique for the determination of air concentrations of organic vapors.

    PubMed

    Saalwaechter, A T; McCammon, C S; Roper, P; Carlberg, K S

    1977-09-01

    The use of the charcoal tube-gas chromatographic method to evaluate workplace air contamination has proliferated greatly in the las 10 years. This report documents early efforts by NIOSH researchers to evaluate several sampling and analytical parameters and their effect on the reliability of the technique. The effects of humidity, sample stability, sample migration and variations in the desorption efficiency are presented. A protocol is suggested for basic testing of the method for new substances. PMID:906963

  8. Use of charcoals and broiler litter biochar for removal of radioactive cesium (Cs-134 plus Cs-137) from contaminated water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Various charcoals (used in food processing and water treatment) and broiler litter biochar were examined for ability to adsorb water-soluble low-level radioactive cesium (ca. 200-250 Bq/kg) extracted from contaminated wheat bran. Among the materials tested, steam activated broiler litter biochar was...

  9. Empirical comparison of neutron activation sample analysis methods

    NASA Astrophysics Data System (ADS)

    Gillenwalters, Elizabeth

    The U.S. Geological Survey (USGS) operates a research reactor used mainly for neutron activation of samples, which are then shipped to industrial customers. Accurate nuclide identification and activity determination are crucial to remain in compliance with Code of Federal Regulations guidelines. This facility utilized a Canberra high purity germanium detector (HPGe) coupled with Canberra Genie(TM) 2000 (G2K) software for gamma spectroscopy. This study analyzed the current method of nuclide identification and activity determination of neutron activated materials utilized by the USGS reactor staff and made recommendations to improve the method. Additionally, analysis of attenuators, effect of detector dead time on nuclide identification, and validity of activity determination assumptions were investigated. The current method of activity determination utilized the G2K software to obtain ratio of activity per nuclide identified. This determination was performed without the use of geometrically appropriate efficiency calibration curves. The ratio of activity per nuclide was used in conjunction with an overall exposure rate in mR/h obtained via a Fluke Biomedical hand-held ion chamber. The overall exposure rate was divided into individual nuclide amounts based on the G2K nuclide ratios. A gamma energy of 1 MeV and a gamma yield of 100% was assumed for all samples. Utilizing the gamma assumption and nuclide ratios, a calculation was performed to determine total sample activity in muCi (microCuries). An alternative method was proposed, which would eliminate the use of exposure rate and rely solely on the G2K software capabilities. The G2K software was energy and efficiency calibrated with efficiency curves developed for multiple geometries. The USGS reactor staff were trained to load appropriate calibration data into the G2K software prior to sample analysis. Comparison of the current method and proposed method demonstrated that the activity value calculated with the 1 Me

  10. Former charcoal kiln sites where forest was cleared for cultivation: a case study of old biochar in cropland

    NASA Astrophysics Data System (ADS)

    Hardy, Brieuc; Dufey, Joseph E.; Cornelis, Jean-Thomas

    2014-05-01

    The use of biochar as a soil amendment is being increasingly investigated as a win-win solution for mitigating the anthropic CO2 emissions and improving soil fertility. However, data on the long term impact of chars on soil properties are scarce, although they are crucial for better understanding the implications of large scale application of highly persistent biochars to soil. In Wallonia (Belgium), old charcoal kilns are found in most of the area that was forested in the late 18th century. Since then, a non-negligible part of the forest has been cleared for cultivation. Today, old charcoal-making platforms can be seen on bare soils as circular or elliptic black spots due to charcoal enrichment. In order to assess the long-term (>200 years) effects of biochar on soil chemical properties, seventeen kiln sites were chosen in several cropland areas of Wallonia on loessic luvisols (14) and loamy cambisols (3). Composite samples were taken in the ploughing layer (0 - 25 cm) and the underlying horizon (35 - 50 cm) in and out the kiln sites. The pH, total carbon (C) and nitrogen (N) contents, oxidizable carbon (CW&B), available phosphorus (Pav), cation exchange capacity at pH 7 (CEC), exchangeable cations content (Ca++, Mg++, K+, Na+) and loss on ignition at 550°C (LI550) were measured. In order to assess the impact of cultivation on charcoal aging, we also sampled four kiln sites on loessic luvisols under forest. Here, we show that charcoal, diluted laterally by successive tillage, acts as a carbon surplus in the topsoil layer of the black spots. The charcoal-enriched horizon is characterized by higher CEC, C/N and C/LI550 ratio compared to the reference soil. Cultivation of former forest soils accelerates charcoal aging, likely due to a combined effect of mechanical (tillage splits charcoal fragments in smaller pieces and increases soil aeration) and biological actions (promoted by improved trophic conditions due to application of amendments and fertilizers over many

  11. Comparison of sampling methods for semi-volatile organic carbonAssociated with PM2.5

    SciTech Connect

    Lewtas, Joellen; Booth, Derrick; Pang, Yanbo; Reimer, Steve; Eatough, Delbert J.; Gundel, Lara A.

    2001-06-29

    This study evaluates the influence of denuder sampling methods and filter collection media on the measurement of semi-volatile organic carbon (SVOC) associated with PM2.5. Two types of collection media, charcoal (activated carbon) and XAD, were used both in diffusion denuders and impregnated back-up filters in two different samplers, the VAPS and the PC-BOSS. The two organic diffusion denuders were XAD-coated glass annular denuders and charcoal-impregnated cellulose fiber filter(CIF) denuders. In addition, recently developed XAD-impregnated quartz filters were compared to CIF filters as back-up filter collection media. The two denuder types resulted in equivalent measurement of particulate organic carbon and particle mass. The major difference observed between the XAD and charcoal BOSS denuders is the higher efficiency of charcoal for collection of more volatile carbon. This more volatile carbon does not contribute substantially to the particle mass or SVOC measured as OC on quartz filters downstream of the denuders. This volatile carbon does result in high OC concentrations observed in charcoal filters placed behind quartz filters downstream of the XAD denuders and would result in overestimating the SVOC in that configuration.

  12. Suppression of charcoal rot in soybean by moderately halotolerant Pseudomonas aeruginosa GS-33 under saline conditions.

    PubMed

    Patil, Sandeep; Paradeshi, Jayasinh; Chaudhari, Bhushan

    2016-08-01

    Charcoal rot severely limits the soybean crop yield under saline conditions. The present studies focus on biocontrol and plant growth promoting potential of phenazine producing moderately halotolerant Pseudomonas aeruginosa (GS-33) in soybean under saline soil conditions. A marine isolate; GS-33 was identified as P. aeruginosa based on polyphasic characterization. This strain showed potent in vitro biocontrol activity against charcoal rot causing fungus Macrophomina phaseolina. It was capable of producing phenazine-1-carboxylic acid even at elevated salt concentrations. Moreover, GS-33 possessed other biocontrol traits like production of siderophores, HCN and protease under saline conditions. Multiple traits for plant growth promotion such as synthesis of IAA, NH3 , and solubilization of phosphate were also exhibited by GS-33. Plant growth promoting and biocontrol control potentials of GS-33 were evaluated by pot assay under saline soil conditions. Higher biomass and chlorophyll content were observed in GS-33 treated seedlings. A greater reduction in charcoal rot caused by fungal pathogens under both normal and saline soil conditions in GS-33 treated seedlings was observed. In a nut shell, phenazine producing halotolerant strain GS-33 could mitigate saline soil conditions (abiotic stress) and infestation of M. phaseolina (biotic stress) in soybean. PMID:27213894

  13. Operationalizing measurement of forest degradation: Identification and quantification of charcoal production in tropical dry forests using very high resolution satellite imagery

    NASA Astrophysics Data System (ADS)

    Dons, K.; Smith-Hall, C.; Meilby, H.; Fensholt, R.

    2015-07-01

    Quantification of forest degradation in monitoring and reporting as well as in historic baselines is among the most challenging tasks in national REDD+ strategies. However, a recently introduced option is to base monitoring systems on subnational conditions such as prevalent degradation activities. In Tanzania, charcoal production is considered a major cause of forest degradation, but is challenging to quantify due to sub-canopy biomass loss, remote production sites and illegal trade. We studied two charcoal production sites in dry Miombo woodland representing open woodland conditions near human settlements and remote forest with nearly closed canopies. Supervised classification and adaptive thresholding were applied on a pansharpened QuickBird (QB) image to detect kiln burn marks (KBMs). Supervised classification showed reasonable detection accuracy in the remote forest site only, while adaptive thresholding was found acceptable at both locations. We used supervised classification and manual digitizing for KBM delineation and found acceptable delineation accuracy at both sites with RMSEs of 25-32% compared to ground measurements. Regression of charcoal production on KBM area delineated from QB resulted in R2s of 0.86-0.88 with cross-validation RMSE ranging from 2.22 to 2.29 Mg charcoal per kiln. This study demonstrates, how locally calibrated remote sensing techniques may be used to identify and delineate charcoal production sites for estimation of charcoal production and associated extraction of woody biomass.

  14. Assessment of anti-Salmonella activity of boot dip samples.

    PubMed

    Rabie, André J; McLaren, Ian M; Breslin, Mark F; Sayers, Robin; Davies, Rob H

    2015-01-01

    The introduction of pathogens from the external environment into poultry houses via the boots of farm workers and visitors presents a significant risk. The use of boot dips containing disinfectant to help prevent this from happening is common practice, but the effectiveness of these boot dips as a preventive measure can vary. The aim of this study was to assess the anti-Salmonella activity of boot dips that are being used on poultry farms. Boot dip samples were collected from commercial laying hen farms in the UK and tested within 24 hours of receipt at the laboratory to assess their anti-Salmonella activity. All boot dip samples were tested against a field strain of Salmonella enterica serovar Enteritidis using three test models: pure culture, paper disc surface matrix and yeast suspension model. Of the 112 boot dip samples tested 83.6% were effective against Salmonella in pure culture, 37.3% in paper disc surface matrix and 44.5% in yeast suspension model. Numerous factors may influence the efficacy of the disinfectants. Disinfectants used in the dips may not always be fully active against surface or organic matter contamination; they may be inaccurately measured or diluted to a concentration other than that specified or recommended; dips may not be changed regularly or may have been exposed to rain and other environmental elements. This study showed that boot dips in use on poultry farms are frequently ineffective. PMID:25650744

  15. RF Magnetic Shielding Effects of a Bincho-Charcoal Plate

    NASA Astrophysics Data System (ADS)

    Itoh, Keisuke; Itoh, Mineo

    Recently, there has been increased interest for electromagnetic shielding in the radio frequency (RF) region. The use of effective electromagnetic shields has, moreover, been required to improve the electromagnetic environment. The present paper has applied bincho-charcoal, a high quality charcoal found in Japan, to improve RF electromagnetic shields. Bincho-charcoal makes an excellent shield, due to a very large value of relative permittivity in the RF region. In the present research, the evaluation of the RF magnetic shielding degree SDH of the bincho-charcoal was limited to a plate being exposed to an electromagnetic wave. The SDH of the single plate was found to increase with an increase in RF frequency over the range from 1 MHz to 1 GHz. The value of SDH at 100 MHz was found to be about 15 dB. The present authors have, furthermore, improved the value of SDH by the use of a triple plate, constructed from three bincho-charcoal plates. The SDH of the triple plate at 100 MHz was found to be improved by about 15 dB over that of the single plate. In addition, the SDH was shown to be improved by the superposition of a copper plate over the triple plate.

  16. [HPLC combined with PCA technology for analysis of five gingerol compounds in different processing degrees of ginger charcoal].

    PubMed

    Yu, Jiang-yong; Chen, Qiu-fang; Lu, Guo-yong

    2015-11-01

    To establish a new method for simultaneously determining the content of five gingerol compounds in different processing degrees of ginger charcoal and PCA principal component analysis was conducted for analysis. Samples were analyzed on Ultimate TM XB-C18 column (4.6 mm x 250 mm, 5 μm) , with acetonitrile (A) -0.1% phosphoric acid solution (B) as mobile phase for gradient elution. Detection wavelength was set at 280 nm. The flow rate was 0.6 mL x min(-1) and the column temperature was 30 degrees C. The five compounds were separated well and showed good linearity (r ≥ 0.999 7) within the concentration ranges tested. The average value for recoveries was between 98.86% - 101.5% (RSD 1.4% - 2.9%). The contents of five compounds showed difference among different processing degrees of ginger charcoal. Zingiberone had the highest content in the standard carbon, and the content of gingerol was decreased as the deepening of processing degree. Different processing degrees of ginger charcoal were classified into three groups with PCA, and provided scientific basis for establishing the quality standards of ginger charcoal. PMID:27071256

  17. Understanding the Impact of Charcoal Inputs to Soils and Sediments on Conventional Geochemical Markers

    NASA Astrophysics Data System (ADS)

    Kuo, L.; Louchouarn, P.; Herbert, B.

    2008-12-01

    increasing combustion temperature, internal phenol ratios (S/V and C/V) show a two-stage change with an initial increase at low temperatures followed by marked and rapid decreases when temperatures reach 200- 250°C. The acid/aldehyde ratios of vanillyl phenols ((Ad/Al)v) and syringyl phenols ((Ad/Al)s) all increase with increasing combustion temperature and duration and reach a maximum values at 300- 350°C, regardless plant species. The highly elevated acid/aldehyde ratios reached in some cases exceed the reported values of humic and fulvic acids extracted from soils and sediments. We applied these empirical data in mixing models to estimate the potential effects of charcoal inputs on the observed lignin signatures in environmental mixtures. The shifts in lignin signatures are strongly influenced both by the characteristics of the charcoal incorporated and the proportion of charcoal in the mixture. We validated our observations with two sets of environmental samples, including soils from control burning sites, and a sediment core from a wetland with evidence of charcoal inputs, showing that the presences of charcoals do alter the observed lignin signals in these samples. Such a thermal "interference" on lignin parameters should thus be considered in environmental mixtures with recognized char input.

  18. Neutron activation analysis of an Egyptian monazite ore sample

    NASA Astrophysics Data System (ADS)

    Eissa, E. A.; Rofail, N. B.; Ashmawy, L. S.; Hassan, A. M.

    1999-01-01

    The absolute sensitivity of a gamma-ray line following thermal or epithermal neutron activation is expressed as a product of four terms, namely, the intrinsic, irradiation, decay and measurement factors. The total absolute sensitivity is the sum of the absolute sensitivities due to thermal and epithermal activation. A. FORTRAN computer program was prepared on the TANDY 3000 NL PCA to calculate the total absolute sensitivity of the intensive gamma-ray lines from the thermal and epithermal neutron activation of all the naturally occurring nuclides. Another program was prepared for the determination of the total absolute sensitivity for gammarays emitted by radioactive daughters such as233Pa from233Th and239Np from239U. Long time irradiation periods (about 48 hours) for specimens of the monazite ore sample were carried out at the (ET-RR-1) reactor core periphery. The monazite ore sample was separated from the associating minerals in the sand of Abou-Khashaba of Rashied (Rosetta) area on the Mediterranean (North of Egypt). The separated monazite ore sample was provided by the Nuclear Material Authority of Egypt. The cadmium difference method was applied to thin gold foils for absolute thermal and epithermal neutron flux determination. The gamma-ray spectra were measured using a spectrometer with a HPGe coaxial detector. The evaluated absolute sensitivity tables were helpful in identifying the radioisotopes contributing to the gamma- ray spectra and in evaluating the elemental concentration of the monazite constitutents. Most of the rare earth elements were observed and their concentrations are reported. La, Ce, Nd, Sd and Th were found as major elements, U, Tb, Hf and Eu as minor elements.

  19. Evaluation of charcoal sorbents for helium cryopumping in fusion reactors

    SciTech Connect

    Tobin, A.G.; Sedgley, D.W.; Batzer, T.H.; Call, W.R.

    1987-01-01

    Improved methods for cryopumping helium were developed for application to fusion reactors where high helium generation rates are expected. In this study, small coconut charcoal granules were utilized as the sorbent, and braze alloys and low temperature curing cements were used as the bonding agents for attachment to a copper support structure. Problems of scale-up of the bonding agent to a 40 cm diam panel were also investigated. Our results indicate that acceptable helium pumping performance of braze bonded and cement bonded charcoals can be achieved over the range of operating conditions expected in fusion reactors.

  20. Charcoal's physical properties are key to understanding its environmental behavior

    NASA Astrophysics Data System (ADS)

    Masiello, Caroline; Brewer, Catherine; Dugan, Brandon; Liu, Zuolin; Gonnermann, Helge; Zygourakis, Kyriacos; Davies, Christian; Panzacchi, Pietro; Gao, Xiaodong; Pyle, Lacey

    2014-05-01

    Charcoal is a highly porous, low density material whose physical properties play a key role in its soil behavior and its environmental fate. In considering biochar, some of its most sought-after environmental effects are a result of its physical characteristics, not its chemical or biological properties. For example, the ability of biochar to retain soil water is widely attributed to its porosity. However, charcoal physical properties are so poorly understood that they are sometimes not characterized at all in the current literature. Here we outline a suite of basic physical properties of charcoal and the likely environmental effects of their variations, with a focus on the interactions between charcoal and water. The most basic physical property of charcoal, its particle size, likely plays a role in its ability to alter the rate of drainage in soils. Particle morphology is also relevant, affecting how particles of soil and char can pack together. Bulk densities of charcoal and soil mixtures can be used to generate a simple estimate of the efficiency of char-soil packing. Charcoal density is an additionally important property and can be measured in a number of ways. Density almost certainly controls the tendency of chars to sink or float, and to erode or remain on the land surface. However, charcoal density can vary by almost a factor of 10 depending on the measurement technique used. We discuss two simple techniques available for measuring char density and the value of information provided by each approach. Finally, we report a simple, fast technique to measure total char porosity, including all pores from nanometers to 10s of micrometers in size. Porosity is at least one of the key controls on the ability of biochar to improve plant-available water, and techniques to measure it have previously been limited to the smallest fraction of pores (N2 sorption) or have required expensive, hazardous procedures (Hg porosimetry). We show that char porosity varies primarily

  1. Instrumental photon activation analysis using the linear accelerator at the Naval Postgraduate School. Master's thesis

    SciTech Connect

    Fisher, W.A.

    1982-10-01

    Charcoal, charcoal residue, potting soil, aluminum foil, bismuth germanate, and petroleum samples have been investigated using instrumental photon activation analysis (i.e., no radiochemistry). The major and minor elements routinely observed by this nondestructive method were: C, C1, Ca, Fe, Mg, Si, and K. A compreshensive review of the principles of IPAA was also included in the study. The principles were applied to a theroetical analysis of an oil sample in which the trace element concentrations were known. It was concluded that IPAA is a highly sensitive technique which could be used to fingerprint oils.

  2. Instrumental photon activation analysis using the linear accelerator at the Naval Postgraduate School

    NASA Astrophysics Data System (ADS)

    Fisher, W. A.

    1982-10-01

    Charcoal, charcoal residue, potting soil, aluminum foil, bismuth germanate, and petroleum samples have been investigated using instrumental photon activation analysis (i.e., no radiochemistry). The major and minor elements routinely observed by this nondestructive method were: C, C1, Ca, Fe, Mg, Si, and K. A comprehensive review of the principles of IPAA was also included in the study. The principles were applied to a theoretical analysis of an oil sample in which the trace element concentrations were known. It was concluded that IPAA is a highly sensitive technique which could be used to fingerprint oils.

  3. Active sampling technique to enhance chemical signature of buried explosives

    NASA Astrophysics Data System (ADS)

    Lovell, John S.; French, Patrick D.

    2004-09-01

    Deminers and dismounted countermine engineers commonly use metal detectors, ground penetrating radar and probes to locate mines. Many modern landmines have a very low metal content, which severely limits the effectiveness of metal detectors. Canines have also been used for landmine detection for decades. Experiments have shown that canines smell the explosives which are known to leak from most types of landmines. The fact that dogs can detect landmines indicates that vapor sensing is a viable approach to landmine detection. Several groups are currently developing systems to detect landmines by "sniffing" for the ultra-trace explosive vapors above the soil. The amount of material that is available to passive vapor sensing systems is limited to no more than the vapor in equilibrium with the explosive related chemicals (ERCs) distributed in the surface soils over and near the landmine. The low equilibrium vapor pressure of TNT in the soil/atmosphere boundary layer and the limited volume of the boundary layer air imply that passive chemical vapor sensing systems require sensitivities in the picogram range, or lower. ADA is working to overcome many of the limitations of passive sampling methods, by the use of an active sampling method that employs a high-powered (1,200+ joules) strobe lamp to create a highly amplified plume of vapor and/or ERC-bearing fine particulates. Initial investigations have demonstrated that this approach can amplify the detectability of TNT by two or three orders of magnitude. This new active sampling technique could be used with any suitable explosive sensor.

  4. Rainforest burning and the global carbon budget: Biomass, combustion efficiency, and charcoal formation in the Brazilian Amazon

    NASA Astrophysics Data System (ADS)

    Fearnside, Philip M.; Leal, Niwton; Fernandes, Fernando Moreira

    1993-01-01

    Biomass present before and after burning was measured in forest cleared for pasture in a cattle ranch (Fazenda Dimona) near Manaus, Amazonas, Brazil. Aboveground dry weight biomass loading averaged 265 t ha-1 (standard deviation (SD) = 110, n = 6 quadrats) at Fazenda Dimona, which corresponds to approximately 311 t ha-1 total dry weight biomass. A five-category visual classification at 200 points showed highly variable burn quality. Postburn aboveground biomass loading was evaluated by cutting and weighing of 100 m2 quadrats and by line intersect sampling. Quadrats had a mean dry weight of 187 t ha-1 (SD = 69, n = 10), a 29.3% reduction from the preburn mean in the same clearing. Line intersect estimates in 1.65 km of transects indicated that 265 m3 ha-1 (approximately 164 t ha-1 of aboveground dry matter) survived burning. Using carbon contents measured for different biomass components (all ˜50% carbon) and assuming a carbon content of 74.8% for charcoal (from other studies near Manaus), the destructive measurements imply a 27.6% reduction of aboveground carbon pools. Charcoal composed 2.5% of the dry weight of the remains in the postburn destructive quadrats and 2.8% of the volume in the line intersect transects. Thus approximately 2.7% of the preburn aboveground carbon stock was converted to charcoal, substantially less than is generally assumed in global carbon models. The findings confirm high values for biomass in central Amazonia. High variability indicates the need for further studies in many localities and for making maximum use of less laborious indirect methods of biomass estimation. While indirect methods are essential for regional estimates of average biomass, only direct weighing such as that reported here can yield information on combustion efficiency and charcoal formation. Both high biomass and low percentage of charcoal formation suggest the significant potential contribution of forest burning to global climate changes from CO2 and trace gases.

  5. Rainforest burning and the global carbon budget: Biomass, combustion efficiency, and charcoal formation in the Brazilian Amazon

    SciTech Connect

    Fearnside, P.M.; Leal, N. Jr.; Fernandes, F.M.

    1993-09-20

    Biomass present before and after burning was measured in forest cleared for pasture in a cattle ranch (Fazenda Dimona) near Manaus, Amazonas, Brazil. Aboveground dry weight biomass loading averaged 265 t ha{sup {minus}1} (standard deviation (SD) = 110, n = 6 quadrats) at Fazenda Dimonas. Postburn aboveground biomass loading was evaluated by cutting and weighing of 100 m{sup 2} quadrats and by line intersect sampling. Quadrats had a mean dry weight of 187 t ha{sup {minus}1} (SD = 69, n = 10), a 29.3% reduction from the preburn mean in the same clearing. Line intersect estimates in 1.65 km of transects indicated that 265 m{sup 3} ha{sup {minus}1} (approximately 164 t ha{sup {minus}1} of aboveground dry matter) survived burning. Using carbon contents measured for different biomass components (all {approximately} 50% carbon) and assuming a carbon content of 74.8% for charcoal (from other studies near Manaus), the destructive measurements imply a 27.6% reduction of aboveground carbon pools. Charcoal composed 2.5% of the dry weight of the remains in the postburn destructive quadrats and 2.8% of the volume in the line intersect transects. Thus approximately 2.7% of the preburn aboveground carbon stock was converted to charcoal, substantially less than is generally assumed in global carbon models. The findings confirm high values for biomass in central Amazonia. High variability indicates the need for further studies in many localities and for making maximum use of less laborious indirect methods of biomass estimation. While indirect methods are essential for regional estimates of average biomass, only direct weighing such as that reported here can yield information on combustion efficiency and charcoal formation. Both high biomass and low percentage of charcoal formation suggest the significant potential contribution of forest burning to global climate changes from CO{sub 2} and trace gases. 66 refs., 6 figs., 2 tabs.

  6. EMISSIONS OF AIR TOXICS FROM A SIMULATED CHARCOAL KILN EQUIPPED WITH AN AFTERBURNER

    EPA Science Inventory

    A laboratory-scale simulator was constructed and tested to determine if it could be used to produce charcoal that was similar to the charcoal that is produced in Missouri-type charcoal kilns. An afterburner was added later to study conditions for oxidizing the volatile organic co...

  7. EMISSIONS OF AIR TOXICS FROM A SIMULATED CHARCOAL KILN EQUIPPED WITH AN AFTERBURNER (PROJECT SUMMARY)

    EPA Science Inventory

    A laboratory-scale charcoal kiln simu-lator was constructed and tested to de-termine if it could be used to produce charcoal that was similar to that pro-duced in Missouri-type charcoal kilns. An afterburner was added later to study conditions for oxidizing the volatile or-ganic ...

  8. EMISSIONS OF AIR TOXICS FROM A SIMULATED CHARCOAL KILN EQUIPPED WITH AN AFTERBURNER

    EPA Science Inventory

    The report discusses emissions of air toxics from a simulated charcoal kiln equipped with an afterburner. A laboratory-scale simulator was constructed and tested to determine if it could be used to produce charcoal that was similar to that produced in Missouri-type charcoal kilns...

  9. 40 CFR 454.10 - Applicability; description of the manufacture of char and charcoal briquets subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... manufacture of char and charcoal briquets subcategory. 454.10 Section 454.10 Protection of Environment... MANUFACTURING POINT SOURCE CATEGORY Char and Charcoal Briquets Subcategory § 454.10 Applicability; description of the manufacture of char and charcoal briquets subcategory. The provisions of this subpart...

  10. 40 CFR 454.10 - Applicability; description of the manufacture of char and charcoal briquets subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... manufacture of char and charcoal briquets subcategory. 454.10 Section 454.10 Protection of Environment... MANUFACTURING POINT SOURCE CATEGORY Char and Charcoal Briquets Subcategory § 454.10 Applicability; description of the manufacture of char and charcoal briquets subcategory. The provisions of this subpart...

  11. URINARY BIOMARKERS IN CHARCOAL WORKERS EXPOSED TO WOOD SMOKE IN BAHIA STATE, BRAZIL

    EPA Science Inventory

    Charcoal is an important source of energy for domestic and industrial use in many countries. In Brazil, the largest producer of charcoal in the world, approximately 350,000 workers are linked to the production and transportation of charcoal. In order to evaluate the occupationa...

  12. 40 CFR 454.10 - Applicability; description of the manufacture of char and charcoal briquets subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... manufacture of char and charcoal briquets subcategory. 454.10 Section 454.10 Protection of Environment... MANUFACTURING POINT SOURCE CATEGORY Char and Charcoal Briquets Subcategory § 454.10 Applicability; description of the manufacture of char and charcoal briquets subcategory. The provisions of this subpart...

  13. 40 CFR 454.10 - Applicability; description of the manufacture of char and charcoal briquets subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... manufacture of char and charcoal briquets subcategory. 454.10 Section 454.10 Protection of Environment... MANUFACTURING POINT SOURCE CATEGORY Char and Charcoal Briquets Subcategory § 454.10 Applicability; description of the manufacture of char and charcoal briquets subcategory. The provisions of this subpart...

  14. 40 CFR 454.10 - Applicability; description of the manufacture of char and charcoal briquets subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... manufacture of char and charcoal briquets subcategory. 454.10 Section 454.10 Protection of Environment... MANUFACTURING POINT SOURCE CATEGORY Char and Charcoal Briquets Subcategory § 454.10 Applicability; description of the manufacture of char and charcoal briquets subcategory. The provisions of this subpart...

  15. Evaluating Waste Charcoal as Potential Rubber Composite Filler

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carbon black, a byproduct of the petroleum industry, is the world's most predominant filler for rubber composites. In this study, charcoal in the form of pyrolyzed agricultural products was evaluated as potential carbon-based filler for rubber composites made with carboxylated styrene-butadiene lat...

  16. Charcoal byproducts as potential styrene-butadiene rubber composte filler

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carbon black, a byproduct of the petroleum industry, is the world's most predominant filler for rubber composites. In this study, various renewable charcoals in the form of pyrolyzed agricultural byproducts were evaluted as potential carbon-based filler for rubber composites made with carboxylated s...

  17. EMISSIONS FROM STREET VENDOR COOKING DEVICES (CHARCOAL GRILLING)

    EPA Science Inventory

    The report discusses a joint U.S./Mexican program to establish a reliable emissions inventory for street vendor cooking devices (charcoal grilling), a significant source of air pollutants in the Mexicali-Imperial Valley area of Mexico. Emissions from these devices, prevalent in t...

  18. Small Scale Charcoal Making: A Manual for Trainers.

    ERIC Educational Resources Information Center

    Karch, Ed; And Others

    This training program offers skills training in all stages of the development of technologies related to small-scale charcoal production, including the design, construction, operation, maintenance, repair, and evaluation of prototype kilns. The kiln designs are selected to be as consistent as possible with the realities of rural areas in…

  19. EMISSIONS FROM STREET VENDOR COOKING DEVICES (CHARCOAL GRILLING) - PROJECT SUMMARY

    EPA Science Inventory

    The report discusses a joint U.S./Mexican program to establish a reliable emissions inventory for street vendor cooking devices (charcoal grilling), a significant source of air pollutants in the Mexicali-Imperial Valley area of Mexico. Emissions from these devices, prevalent in t...

  20. Microsatellites from the charcoal rot fungus (Macrophomina phaseolina)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microsatellite loci were identified from the charcoal rot fungus Macrophomina phaseolina. Primer pairs for 46 loci were developed and of these 13 were optimized and screened using genomic DNA from 44 fungal isolates collected predominantly from two soybean fields in MS. All optimized loci were poly...

  1. Paired charcoal and tree-ring records of high-frequency Holocene fire from two New Mexico bog sites

    USGS Publications Warehouse

    Allen, C.D.; Anderson, R. Scott; Jass, R.B.; Toney, J.L.; Baisan, C.H.

    2008-01-01

    Two primary methods for reconstructing paleofire occurrence include dendrochronological dating of fire scars and stand ages from live or dead trees (extending back centuries into the past) and sedimentary records of charcoal particles from lakes and bogs, providing perspectives on fire history that can extend back for many thousands of years. Studies using both proxies have become more common in regions where lakes are present and fire frequencies are low, but are rare where high-frequency surface fires dominate and sedimentary deposits are primarily bogs and wetlands. Here we investigate sedimentary and fire-scar records of fire in two small watersheds in northern New Mexico, in settings recently characterised by relatively high-frequency fire where bogs and wetlands (Chihuahuen??os Bog and Alamo Bog) are more common than lakes. Our research demonstrates that: (1) essential features of the sedimentary charcoal record can be reproduced between multiple cores within a bog deposit; (2) evidence from both fire-scarred trees and charcoal deposits documents an anomalous lack of fire since ???1900, compared with the remainder of the Holocene; (3) sedimentary charcoal records probably underestimate the recurrence of fire events at these high-frequency fire sites; and (4) the sedimentary records from these bogs are complicated by factors such as burning and oxidation of these organic deposits, diversity of vegetation patterns within watersheds, and potential bioturbation by ungulates. We consider a suite of particular challenges in developing and interpreting fire histories from bog and wetland settings in the Southwest. The identification of these issues and constraints with interpretation of sedimentary charcoal fire records does not diminish their essential utility in assessing millennial-scale patterns of fire activity in this dry part of North America. ?? IAWF 2008.

  2. Extravehicular Activity Asteroid Exploration and Sample Collection Capability

    NASA Technical Reports Server (NTRS)

    Sipila, Stephanie A.; Scoville, Zebulon C.; Bowie, Jonathan T.; Buffington, Jesse A.

    2014-01-01

    One of the challenging primary objectives associated with NASA's Asteroid Redirect Crewed Mission (ARCM) is to demonstrate deep space Extravehicular Activity (EVA) and tools and to obtain asteroid samples to return to Earth for further study. Prior Shuttle and International Space Station (ISS) spacewalks have benefited from engineered EVA interfaces which have been designed and manufactured on Earth. Rigid structurally mounted handrails, and tools with customized interfaces and restraints optimize EVA performance. For ARCM, EVA complexity increases due to the uncertainty of the asteroid properties. The variability of rock size, shape and composition, as well as behavior of the asteroid capture mechanism will complicate EVA translation, tool restraint, and body stabilization. The unknown asteroid hardness and brittleness will complicate tool use. The rock surface will introduce added safety concerns for cut gloves and debris control. Feasible solutions to meet ARCM EVA objectives were identified using experience gained during Apollo, Shuttle, and ISS EVAs, terrestrial mountaineering practices, NASA Extreme Environment Mission Operations (NEEMO) 16 mission, and during Neutral Buoyancy Laboratory testing in the Modified Advanced Crew Escape Suit (MACES) suit. This paper will summarize the overall operational concepts for conducting EVAs for the ARCM mission including translation paths and body restraint methods, potential tools used to extract the samples, design implications for the Asteroid Redirect Vehicle (ARV) for EVA, and the results of early development testing of potential EVA tasks.

  3. Charcoal and fly-ash particles from Lake Lucerne sediments (Central Switzerland) characterized by image analysis: anthropologic, stratigraphic and environmental implications

    NASA Astrophysics Data System (ADS)

    Thevenon, Florian; Anselmetti, Flavio S.

    2007-10-01

    In order to link the charcoal record from sedimentary archives with the combustion processes that reflect past anthropogenic activity, a novel method based on automated image analysis was developed. It allows a detailed quantification and morphological analysis of the combustion-derived products that were emitted in the area of Lake Lucerne (Central Europe) throughout the last 7200 years. Charcoal-particle distribution reconstructed from the composite sedimentary record shows that the charcoal input is primarily linked to redistribution of detrital μm-size charcoal degradation products from surface runoff into the large lake basin. However, the independent distribution of the coarser charcoal fraction (>38 μm) exhibits four major periods of large-scale fire activity around 5500, 3300, 2400, and 530 cal. BP. These events are synchronous with major anthropogenic changes (lake-dwellings, land-use changes, technological innovations), although it is possible that these major fire episodes could have been indirectly triggered by climatic deterioration and unfavorable environmental conditions. During the late-nineteenth-century, a great increase in slag particles and magnetic spherules of fly-ash occurred due to the steamboat navigation on Lake Lucerne. The successive burning of wood (after AD 1838), coal (after AD 1862), and diesel (after AD 1931) by the steamboat traffic produced specific particle shapes, providing valuable chronological markers for dating the recent sediments and a proxy for fossil fuel combustion.

  4. [Labor process and workers' health in charcoal production in Minas Gerais, Brazil].

    PubMed

    Dias, Elizabeth Costa; Assuncao, Ada Avila; Guerra, Cláudio Bueno; Cano Prais, Hugo Alejandro

    2002-01-01

    This study is a tentative approach to the relationship between environmental and occupational health and development in a specific situation: charcoal production in the Jequitinhonha Valley, the poorest region in the State of Minas Gerais, Brazil. The study focuses on the labor process, involving heavy exploitation, hazardous working conditions, and extremely precarious living conditions. Working conditions and activities are described and related to the workers' health situation. Social policies and decisive participation by the various social stakeholders are necessary to change this reality. PMID:11910445

  5. Extravehicular Activity Asteroid Exploration and Sample Collection Capability

    NASA Technical Reports Server (NTRS)

    Scoville, Zebulon; Sipila, Stephanie; Bowie, Jonathan

    2014-01-01

    NASA's Asteroid Redirect Crewed Mission (ARCM) is challenged with primary mission objectives of demonstrating deep space Extravehicular Activity (EVA) and tools, and obtaining asteroid samples to return to Earth for further study. Although the Modified Advanced Crew Escape Suit (MACES) is used for the EVAs, it has limited mobility which increases fatigue and decreases the crews' capability to perform EVA tasks. Furthermore, previous Shuttle and International Space Station (ISS) spacewalks have benefited from EVA interfaces which have been designed and manufactured on Earth. Rigid structurally mounted handrails, and tools with customized interfaces and restraints optimize EVA performance. For ARCM, some vehicle interfaces and tools can leverage heritage designs and experience. However, when the crew ventures onto an asteroid capture bag to explore the asteroid and collect rock samples, EVA complexity increases due to the uncertainty of the asteroid properties. The variability of rock size, shape and composition, as well as bunching of the fabric bag will complicate EVA translation, tool restraint and body stabilization. The unknown asteroid hardness and brittleness will complicate tool use. The rock surface will introduce added safety concerns for cut gloves and debris control. Feasible solutions to meet ARCM EVA objectives were identified using experience gained during Apollo, Shuttle, and ISS EVAs, terrestrial mountaineering practices, NASA Extreme Environment Mission Operations (NEEMO) 16 mission, and during Neutral Buoyancy Laboratory testing in the MACES suit. The proposed concept utilizes expandable booms and integrated features of the asteroid capture bag to position and restrain the crew at the asteroid worksite. These methods enable the capability to perform both finesse, and high load tasks necessary to collect samples for scientific characterization of the asteroid. This paper will explore the design trade space and options that were examined for EVA, the

  6. Concentration of trace elements, technogenic magnetic particles and charcoal in peat profiles as an evidence of thousands years of ore exploitation

    NASA Astrophysics Data System (ADS)

    Mendakiewicz, Maria; Magiera, Tadeusz; Szuszkiewicz, Marcin; Chróst, Leszek; Szopa, Sebastian

    2014-05-01

    The aim of the research is the geochemical and magnetic characteristic of peat bog profiles covered with a thin layer of fluvioglacial deposits appearing in the valley of the upper Brynica river (Upper Silesia, Poland). The research was supported with radiometric dating. The upper part of the Brynica basin has been the area of human activities since the Mesolithic through the Neolithic up to now, including intensive mining-smelting activities connected with the exploitation of Fe, Pb and Ag. In order to determine the geochemical composition a method of X-ray fluorescence (EDXRF) was used. The study revealed a high concentration of such chemical elements as Ag (at a depth of 15, 70, 80 and 95 cm), Cu (at a depth of 15 and 55 cm) as well as Pb and Sn (at a depth of 15 cm). The chemical pollution corresponds to the presence of technogenic magnetic particles (TMPs) in the peat bog profiles. The TMPs occur mainly in the form of iron and hydroxides of ferro- and ferrimagnetic properties and they come into existence during different high temperature technological processes. Their presence in the peat bog profiles as well as corresponding pollution together with charcoal suggest application of fire techniques to acquire metals from ore a few thousand years ago. MS2 Bartington meter with MS2B sensor was used to detect the TMPs and the age of the pollution was determined by the application of the radiocarbon method (C-14). The radiometric research was carried out in peat bog samples taken from the most polluted horizons and in charcoal particles separated from the profiles. The results of the dating indicate the highest concentration of pollution in peat bog profiles for the periods of 500 AD and 1200, 5500 as well as 9500 BC. The connection of geochemical and magnetic analyses used in the research appeared as an effective methods to detect and interpretation a trace evidence of human activities from a many thousand years in the past.

  7. Detection of autoinducer (AI-2)-like activity in food samples.

    PubMed

    Sivakumar, Kirthiram K; Jesudhasan, Palmy R; Pillai, Suresh D

    2011-01-01

    The contamination, survival, and possible foodborne disease outbreaks are major issues confronting the food industry. However, from a microbial perspective, any food whether natural or processed is just another environmental niche that is available for colonization. Quorum sensing or cell-cell communication is a process by which microorganisms are thought to communicate with each other using a variety of small molecules termed autoinducers. The autoinducer AI-2 is thought to be a universal signaling molecule due to its ability to modulate the gene expression of a number of different bacterial species and genera. Pathogens such as Pseudomonas aeruginosa, Aeromonas hydrophila, Vibrio anguillarum, Streptococcus sp., and Burkholderia cepacia form biofilms on a variety of man-made and natural surfaces using cell-cell mechanisms. It is important to detect and study autoinducers and their activities in foods, since a better understanding of these molecules in food and food ingredients may help in designing new approaches to thwart microbial persistence and biofilm formation. The autoinducer AI-2 is thought to be involved in microbial attachment and biofilm formation leading to food spoilage. To better understand microbial cell-cell signaling in foods especially as it relates to pathogen persistence, biofilm formation, and food spoilage, methods to process, extract, and purify autoinducer molecules need to be developed. This chapter details methods to process food samples to obtain cell-free supernatants (CFS), which could subsequently be tested for the presence of AI-2 or "AI-2-like activity" in the extracted CFS using autoinducer bioassays. Additionally, the method of synthesizing AI-2 in the laboratory is also provided. The methods that are presented in this chapter are based on previously published research articles from the authors' laboratory. PMID:21031305

  8. Development of a sampling and analytical method for 2,2-dichloro-1,1,1-trifluoroethane in workplace air.

    PubMed

    Shin, Yong Chul; Yi, Gwang Yong; Kim, Yangho; Paik, Nam Won

    2002-01-01

    The use of 2,2-dichloro-1,1,1-trifluoroethane (compound number: HCFC-123) is growing in industry as a substitute for ozone-depleting chlorofluorocarbons (CFCs). Recently, liver-related illnesses have been reported from industries handling HCFC-123. However, information on worker exposure to the material is limited, and an acceptable sampling/analytical method is not available. The aim of this study was to develop a widely applicable sampling and analytical method to determine worker exposures to airborne HCFC-123 and to evaluate the performance of the method. A solid sorbent tube, containing two sections (400 mg in the front and 200 mg in the back) of activated coconut-shell charcoal was chosen for sampling airborne HCFC-123 vapor. The breakthrough volumes were 13.6 L at 3597 +/- 210.1 ppm (with a sampling airflow rate of 0.046 L/min) and 17.0 L at 1841 +/- 4.5 ppm (with sampling airflow rate of 0.046-0.050 L/min). Samples of HCFC-123 in the charcoal tube were stable for 7 days either at room temperature or in a refrigerator and a migration occurred within 14 days at room temperature. It is recommended that the HCFC-123 sample in activated charcoal tubes be stored either at room temperature or in a refrigerator and be analyzed within 7 days. The HCFC-123 in the charcoal tubes was desorbed into dichloromethane and analyzed using gas chromatography/ flame ionization detection. The limit of detection was 0.23 mg/sample, and the average desorption efficiency was 99.0%. The total coefficient of variation was 0.060, and the method accuracy was 16.6%. In conclusion, the performance of the sampling and analytical method developed for the determination of airborne HCFC-123 concentrations was acceptable to the NIOSH sampling and analytical criteria. PMID:12570079

  9. Effects of autoclaving and charcoal on root-promoting substances present in water extracts made from gelling agents.

    PubMed

    Arthur, G D; Stirk, W A; Van Staden, J

    2006-10-01

    The root-promoting ability of water extracts made from gelling agents (agar and Gelrite) was investigated using the mungbean rooting bioassay. Autoclaving these water extracts decreased the number of roots in mungbean cuttings compared to the controls. The addition of activated charcoal to the water extracts from Agar Bacteriological and Agar Commercial Gel had no effect on their root-promoting ability. Extracts with exogenous indole-3-butyric acid (IBA) which were treated by autoclaving or via a freeze-thaw cycle, significantly increased rooting. However, incorporation of activated charcoal to similar IBA-containing extracts reduced rooting. Our results indicate that more attention should be given to the choice of gelling agent and its interaction with other additives in the media used during tissue culture. PMID:16274988

  10. Spatiotemporal patterns of tundra fires: late-Quaternary charcoal records from Alaska

    NASA Astrophysics Data System (ADS)

    Chipman, M. L.; Hudspith, V.; Higuera, P. E.; Duffy, P. A.; Kelly, R.; Oswald, W. W.; Hu, F. S.

    2015-07-01

    Anthropogenic climate change has altered many ecosystem processes in the Arctic tundra and may have resulted in unprecedented fire activity. Evaluating the significance of recent fires requires knowledge from the paleofire record because observational data in the Arctic span only several decades, much shorter than the natural fire rotation in Arctic tundra regions. Here we report results of charcoal analysis on lake sediments from four Alaskan lakes to infer the broad spatial and temporal patterns of tundra-fire occurrence over the past 35 000 years. Background charcoal accumulation rates are low in all records (range is 0-0.05 pieces cm-2 yr-1), suggesting minimal biomass burning across our study areas. Charcoal peak analysis reveals that the mean fire-return interval (FRI; years between consecutive fire events) ranged from ca. 1650 to 6050 years at our sites, and that the most recent fire events occurred from ca. 880 to 7030 years ago, except for the CE 2007 Anaktuvuk River Fire. These mean FRI estimates are longer than the fire rotation periods estimated for the past 63 years in the areas surrounding three of the four study lakes. This result suggests that the frequency of tundra burning was higher over the recent past compared to the late Quaternary in some tundra regions. However, the ranges of FRI estimates from our paleofire records overlap with the expected values based on fire-rotation-period estimates from the observational fire data, and the differences are statistically insignificant. Together with previous tundra-fire reconstructions, these data suggest that the rate of tundra burning was spatially variable and that fires were extremely rare in our study areas throughout the late Quaternary. Given the rarity of tundra burning over multiple millennia in our study areas and the pronounced effects of fire on tundra ecosystem processes such as carbon cycling, dramatic tundra ecosystem changes are expected if anthropogenic climate change leads to more

  11. Guidance for establishment and implementation of field sample management programs in support of EM environmental sampling and analysis activities

    SciTech Connect

    Not Available

    1994-02-18

    The role of the National Sample Management Program (NSMP) proposed by the Department of Energy`s Office of Environmental Management (EM) is to be a resource for EM programs and for local Field Sample Management Programs (FSMPs). It will be a source of information on sample analysis and data collection within the DOE complex. The purpose of this document is to establish the suggested scope of the FSMP activities to be performed under each Operations Office, list the drivers under which the program will operate, define terms and list references. This guidance will apply only to EM sampling and analysis activities associated with project planning, contracting, laboratory selection, sample collection, sample transportation, laboratory analysis and data management.

  12. Charcoal analysis and Holocene vegetation history in southern Syria

    NASA Astrophysics Data System (ADS)

    Willcox, George

    1999-04-01

    Charcoal analysis of three archaeological sites in southern Syria in the vicinity of the Jebel al Arab (formerly Jebel Druze) indicates that during the Early Bronze Age an association consisting predominately of Pistacia, deciduous oak and almond was exploited. During the Middle Bronze Age these taxa diminish and are partially replaced by more steppic species or introduced wood such as olive. During the Roman period evergreen oak appeared in the region and gradually replaced the deciduous oak which is now restricted to a small area. The gradual replacement of deciduous oaks by evergreen oaks has been observed in other areas of the Mediterranean basin during the Holocene. Conifer charcoal such as pine and cedar is present on the sites, but it is not clear whether these were local or imported from farther away, for example, the Lebanese highlands. During the Middle Bronze Age olive wood was also used as combustible but here also its exact origin is not known.

  13. Modelling the combustion of charcoal in a model blast furnace

    NASA Astrophysics Data System (ADS)

    Shen, Yansong; Shiozawa, Tomo; Yu, Aibing; Austin, Peter

    2013-07-01

    The pulverized charcoal (PCH) combustion in ironmaking blast furnaces is abstracting remarkable attention due to various benefits such as lowering CO2 emission. In this study, a three-dimensional CFD model is used to simulate the flow and thermo-chemical behaviours in this process. The model is validated against the experimental results from a pilot-scale combustion test rig for a range of conditions. The typical flow and thermo-chemical phenomena is simulated. The effect of charcoal type, i.e. VM content is examined, showing that the burnout increases with VM content in a linear relationship. This model provides an effective way for designing and optimizing PCH operation in blast furnace practice.

  14. Internal sample attenuator counting (ISAC). A new technique for separating and measuring bound and free activity in radioimmunoassays

    SciTech Connect

    Thorell, J.I.

    1981-12-01

    A new method for the separation counting of bound and free activity in radioimmunoassays is described. Particles containing a radiation-abosrbing (attenuating) material are added to the assay. They shield the radiation from either the antibody-bound or the free radioligand. This obviates such manipulations conventionally involved in the separation and counting steps of radioimmunoassays as centrifugation decanting. Bismuth oxide is used as the attenuator. Particles with different properties are described. In one type, bismuth oxide is combined with active charcoal in an agarose matrix and serves as an absorbant for the free radioligand. In another type bismuth oxide is trapped within a polyacrylamide matrix to which antibodies are coupled. This particle can be used with a first- or a second-antibody bound activity. Application of the technique is illustrated with radioimmunoassays for thyroxin, triiodothyronine, human choriogonadotropin, and lutropin (luteinizing hormone).

  15. Charcoal-methanol adsorption refrigerator powered by a compound parabolic concentrating solar collector

    SciTech Connect

    Headley, O.StC.; Kothdiwala, A.F.; McDoom, I.A. )

    1994-08-01

    A compound parabolic concentrating solar collector (CPC) of concentration ratio 3.9 and aperture area 2.0 m[sup 2] was used to power an intermittent solid adsorption refrigerator and ice maker using activated charcoal (carbon) as the adsorbing medium and methanol as the working fluid. The copper tube receiver of the CPC was packed with 2.5 kg of imported adsorbent 207E3, which was only utilized when the performance of activated charcoal (ACJ1, produced from local coconut shells) was found to be inferior to the imported adsorbent. Up to 1 kg of ice at an evaporator temperature of [minus]6[degrees]C was produced, with the net solar coefficient of performance (COP) being of the order of 0.02. Maximum receiver/adsorbent temperature recorded was 154[degrees]C on a day when the insolation was 26.8 MJ/m[sup [minus]2]. Temperatures in excess of 150[degrees]C are undesirable since they favour the conversion of methanol to dimethyl ether, a noncondensable gas which inhibits both condensation and adsorption. The major advantage of this system is its ability to produce ice even on overcast days (insolation [approximately] 10 MJ/m[sup [minus]2]).

  16. The Impact of Media Reporting on the Emergence of Charcoal Burning Suicide in Taiwan

    PubMed Central

    Chen, Ying-Yeh; Chen, Feng; Gunnell, David; Yip, Paul S. F.

    2013-01-01

    We investigated the association of the intensity of newspaper reporting of charcoal burning suicide with the incidence of such deaths in Taiwan during 1998–2002. A counting process approach was used to estimate the incidence of suicides and intensity of news reporting. Conditional Poisson generalized linear autoregressive models were performed to assess the association of the intensity of newspaper reporting of charcoal burning and non-charcoal burning suicides with the actual number of charcoal burning and non-charcoal burning suicides the following day. We found that increases in the reporting of charcoal burning suicide were associated with increases in the incidence of charcoal burning suicide on the following day, with each reported charcoal burning news item being associated with a 16% increase in next day charcoal burning suicide (p<.0001). However, the reporting of other methods of suicide was not related to their incidence. We conclude that extensive media reporting of charcoal burning suicides appears to have contributed to the rapid rise in the incidence of the novel method in Taiwan during the initial stage of the suicide epidemic. Regulating media reporting of novel suicide methods may prevent an epidemic spread of such new methods. PMID:23383027

  17. NMR characterization of 13C-benzene sorbed to natural and prepared charcoals.

    PubMed

    Smernik, Ronald J; Kookana, Rai S; Skjemstad, Jan O

    2006-03-15

    We investigated how the NMR properties of uniformly 13C-labeled benzene molecules are influenced by sorption to charcoals produced in the laboratory and collected from the field following wildfires. Uniformly 13C-labeled benzene was sorbed to two charcoals produced in the laboratory at 450 and 850 degrees C. The chemical shift of benzene sorbed to the higher-temperature charcoal was 5-6 ppm lower than that of benzene sorbed to the lower-temperature charcoal. This difference was attributed to stronger diamagnetic ring currents (which cause a shift to lower ppm values) in the more condensed or "graphitic" high-temperature charcoal. The chemical shift of benzene sorbed to two charcoals collected from the field following wildfires indicated a degree of charcoal graphitization intermediate between that of the two laboratory-prepared charcoals. Variable contact time and dipolar dephasing experiments showed that the molecular mobility of sorbed benzene molecules increased with increasing charcoal graphitization, and also increased with increasing benzene concentration. We propose that the chemical shift displacement of molecules sorbed to charcoal could be used to identify molecules sorbed to black carbon in heterogeneous matrixes such as soils and sediments, and to establish how condensed or "graphitic" the black carbon is. PMID:16570595

  18. Sampling trace organic compounds in water: a comparison of a continuous active sampler to continuous passive and discrete sampling methods

    USGS Publications Warehouse

    Coes, Alissa L.; Paretti, Nicholas V.; Foreman, William T.; Iverson, Jana L.; Alvarez, David A.

    2014-01-01

    A continuous active sampling method was compared to continuous passive and discrete sampling methods for the sampling of trace organic compounds (TOCs) in water. Results from each method are compared and contrasted in order to provide information for future investigators to use while selecting appropriate sampling methods for their research. The continuous low-level aquatic monitoring (CLAM) sampler (C.I.Agent® Storm-Water Solutions) is a submersible, low flow-rate sampler, that continuously draws water through solid-phase extraction media. CLAM samplers were deployed at two wastewater-dominated stream field sites in conjunction with the deployment of polar organic chemical integrative samplers (POCIS) and the collection of discrete (grab) water samples. All samples were analyzed for a suite of 69 TOCs. The CLAM and POCIS samples represent time-integrated samples that accumulate the TOCs present in the water over the deployment period (19–23 h for CLAM and 29 days for POCIS); the discrete samples represent only the TOCs present in the water at the time and place of sampling. Non-metric multi-dimensional scaling and cluster analysis were used to examine patterns in both TOC detections and relative concentrations between the three sampling methods. A greater number of TOCs were detected in the CLAM samples than in corresponding discrete and POCIS samples, but TOC concentrations in the CLAM samples were significantly lower than in the discrete and (or) POCIS samples. Thirteen TOCs of varying polarity were detected by all of the three methods. TOC detections and concentrations obtained by the three sampling methods, however, are dependent on multiple factors. This study found that stream discharge, constituent loading, and compound type all affected TOC concentrations detected by each method. In addition, TOC detections and concentrations were affected by the reporting limits, bias, recovery, and performance of each method.

  19. Sampling trace organic compounds in water: a comparison of a continuous active sampler to continuous passive and discrete sampling methods.

    PubMed

    Coes, Alissa L; Paretti, Nicholas V; Foreman, William T; Iverson, Jana L; Alvarez, David A

    2014-03-01

    A continuous active sampling method was compared to continuous passive and discrete sampling methods for the sampling of trace organic compounds (TOCs) in water. Results from each method are compared and contrasted in order to provide information for future investigators to use while selecting appropriate sampling methods for their research. The continuous low-level aquatic monitoring (CLAM) sampler (C.I.Agent® Storm-Water Solutions) is a submersible, low flow-rate sampler, that continuously draws water through solid-phase extraction media. CLAM samplers were deployed at two wastewater-dominated stream field sites in conjunction with the deployment of polar organic chemical integrative samplers (POCIS) and the collection of discrete (grab) water samples. All samples were analyzed for a suite of 69 TOCs. The CLAM and POCIS samples represent time-integrated samples that accumulate the TOCs present in the water over the deployment period (19-23 h for CLAM and 29 days for POCIS); the discrete samples represent only the TOCs present in the water at the time and place of sampling. Non-metric multi-dimensional scaling and cluster analysis were used to examine patterns in both TOC detections and relative concentrations between the three sampling methods. A greater number of TOCs were detected in the CLAM samples than in corresponding discrete and POCIS samples, but TOC concentrations in the CLAM samples were significantly lower than in the discrete and (or) POCIS samples. Thirteen TOCs of varying polarity were detected by all of the three methods. TOC detections and concentrations obtained by the three sampling methods, however, are dependent on multiple factors. This study found that stream discharge, constituent loading, and compound type all affected TOC concentrations detected by each method. In addition, TOC detections and concentrations were affected by the reporting limits, bias, recovery, and performance of each method. PMID:24419241

  20. Measurement of the axial distribution of radioactivity in the auxiliary charcoal bed of the Molten Salt Reactor Experiment at ORNL

    SciTech Connect

    Miller, L.F.; Buckner, M.; Buchanan, M.

    1999-07-01

    The Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory commenced operation in 1964 and was shut down in 1969. It was fueled with {sup 233}UF{sub 4} in a carrier salt of LiF-BeF{sub 2}-ZrF{sub 4}, and it operated at 1,200 F. After it was shut down, the fuel was heated annually to 200 C to recombine fluorine (with the fuel) released due to radiation-induced reactions in the fuel salt. However, a competing reaction oxidized uranium to UF{sub 6}, which was released (along with F{sub 2}) from the fuel and trapped in one of four charcoal filters in the auxiliary charcoal bed (ACB). One of the tasks for decommissioning of the MSRE requires that at least 90% of the estimated 3 kg of {sup 233}U, and radioactive decay products, in this filter be removed, and one of the proposed methods is to vacuum the charcoal above a specified axial position in the filter. This requires that the axial distribution of activity in the filter be measured in a 60 rad/h radiation field to determine where this penetration can be made. To accomplish this, the shielded detector with a pinhole collimator, and with a laser positioning capability, was remotely translated to various axial positions to accomplish these measurements. Activities in the steel screen, and various regions of the charcoal bed, are estimated, and uncertainties in these estimates are generally {lt}1%. Results from this analysis are used for continued operational decisions for decommissioning of the MSRE.

  1. Removal of radioactive cesium (134Cs plus 137Cs) from low-level contaminated water by charcoal and broiler litter biochar

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Various charcoals (used in food processing and water treatment) and broiler litter biochar were examined for ability to adsorb water-soluble low-level radioactive cesium (ca. 200-250 Bq/kg) extracted from contaminated wheat bran. Among the materials tested, steam activated broiler litter biochar was...

  2. Activated sampling in complex materials at finite temperature: The properly obeying probability activation-relaxation technique

    NASA Astrophysics Data System (ADS)

    Vocks, Henk; Chubynsky, M. V.; Barkema, G. T.; Mousseau, Normand

    2005-12-01

    While the dynamics of many complex systems is dominated by activated events, there are very few simulation methods that take advantage of this fact. Most of these procedures are restricted to relatively simple systems or, as with the activation-relaxation technique (ART), sample the conformation space efficiently at the cost of a correct thermodynamical description. We present here an extension of ART, the properly obeying probability ART (POP-ART), that obeys detailed balance and samples correctly the thermodynamic ensemble. Testing POP-ART on two model systems, a vacancy and an interstitial in crystalline silicon, we show that this method recovers the proper thermodynamical weights associated with the various accessible states and is significantly faster than molecular dynamics in the simulations of a vacancy below 700 K.

  3. Activated sampling in complex materials at finite temperature: the properly obeying probability activation-relaxation technique.

    PubMed

    Vocks, Henk; Chubynsky, M V; Barkema, G T; Mousseau, Normand

    2005-12-22

    While the dynamics of many complex systems is dominated by activated events, there are very few simulation methods that take advantage of this fact. Most of these procedures are restricted to relatively simple systems or, as with the activation-relaxation technique (ART), sample the conformation space efficiently at the cost of a correct thermodynamical description. We present here an extension of ART, the properly obeying probability ART (POP-ART), that obeys detailed balance and samples correctly the thermodynamic ensemble. Testing POP-ART on two model systems, a vacancy and an interstitial in crystalline silicon, we show that this method recovers the proper thermodynamical weights associated with the various accessible states and is significantly faster than molecular dynamics in the simulations of a vacancy below 700 K. PMID:16396563

  4. Sample Energy Conservation Education Activities for Elementary School Students.

    ERIC Educational Resources Information Center

    Allen, Rodney F., Ed.; LaHart, David E., Ed.

    The booklet contains learning activities for introducing energy and conservation concepts into the existing elementary school curriculum. The activities were developed by Palm Beach County teachers during a one-week workshop. A framework of ideas is divided into three functional categories: universe of energy, living systems and energy, and social…

  5. Jazz Listening Activities: Children's Literature and Authentic Music Samples.

    ERIC Educational Resources Information Center

    McDonald, Nan L.; Fisher, Douglas; Helzer, Rick

    2002-01-01

    Describes a unit that is appropriate for upper elementary and middle school students that focuses on jazz music using biographies about jazz musicians. Discusses the five sections of the unit. Includes a list of "Suggested Jazz Listening Samples," jazz videos, and a bibliography of resources related to jazz music. (CMK)

  6. Charcoal morphometry for paleoecological analysis: The effects of fuel type and transportation on morphological parameters1

    PubMed Central

    Crawford, Alastair J.; Belcher, Claire M.

    2014-01-01

    • Premise of the study: Charcoal particles preserved in sediments are used as indicators of paleowildfire. Most research focuses on abundance as an indicator of fire frequency, but charcoals also convey information about the vegetation from which they are derived. One potential source of information is their morphology, which is influenced by the parent material, the nature of the fire, and subsequent transportation and burial. • Methods: We charcoalified 26 materials from a range of plant taxa, and subjected them to simulated fluvial transport by tumbling them with water and gravel. We photographed the resulting particles, and used image analysis software to measure morphological parameters. • Results: Leaf charcoal displayed a logarithmic decrease in area, and a logarithmic increase in circularity, with transportation time. Trends were less clear for stem or wood charcoal. Grass charcoal displayed significantly higher aspect ratios than other charcoal types. • Conclusions: Leaf charcoal displays more easily definable relationships between morphological parameters and degree of breakdown than stem or wood charcoal. The aspect ratios of fossil mesocharcoal can indicate the broad botanical source of an assemblage. Coupled to estimates of charcoal abundance, this will improve understanding of the variation in flammability of ancient ecosystems. PMID:25202644

  7. The effect of weathering on charcoal filter performance. 2; The effect of contaminants on the CH sub 3 I removal efficiency of TEDA charcoal

    SciTech Connect

    Wren, J.C.; Moore, C.J. )

    1991-05-01

    The effect of various contaminants, namely NO{sub 2} SO{sub 2}, 2-butanone (methyl-ethyl-ketone (MEK)), and NH{sub 3}, on the radioiodine removal efficiency of triethylenediamine (TEDA)-impregnated charcoal filters has been studied, and an attempt was made to characterize and quantify the weathering process of TEDA charcoal by these contaminants. The effects of the contaminants on the CH{sub 3}I removal efficiency of TEDA charcoal under dry and humid conditions are described. Based on our results, the efficiency of TEDA charcoal is degraded most by NO{sub 2} and SO{sub 2}, NH{sub 3} has a negligible effect, and MEK produces a mild degradation. The degree of degradation parallels the contaminant's ability to be chemisorbed on the TEDA impregnant. The combined effect of water vapor and a contaminant of the charcoal efficiency is different for each contaminant. Nitrogen dioxide absorbed under dry conditions is more effective in degrading the CH{sub 2}I removal efficiency of the charcoal that when absorbed under humid conditions. On the other hand, a completely opposite result is observed for SO{sub 2}. The MEK contaminant behaves similarly to SO{sub 2} but the effect of humidity was less significant than for SO{sub 2}. Ammonia has no effect on the efficiency of the charcoal regardless of humidity.

  8. Impact of Plasma Surface Treatment on Bamboo Charcoal/silver Nanocomposite

    NASA Astrophysics Data System (ADS)

    Vignesh, K.; Vijayalakshmi, K. A.; Karthikeyan, N.

    2016-10-01

    Bamboo charcoal (BC) accompanied silver (Ag) nanocomposite is synthesized through sol-gel method. The produced BC/Ag nanocomposite was surface modified by air and oxygen plasma treatments. Silver ions (Ag+) will serve to improve the antibacterial activity as well as the surface area of BC. Plasma treatment has improved the surface functional groups, crystalline intensity and antibacterial activity of the prepared nanocomposite. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) studies show that Ag nanoparticles have good agreement with BC and the particle size has a mean diameter of 20-40nm. We observe the carboxyl functional groups in Fourier transform infrared spectroscopy (FTIR) after the oxygen plasma treatment. Moreover surface area and adsorption were analyzed by using the Brunauer, Emmett and Teller (BET) surface area (SBET) and UV-Vis spectroscopy.

  9. Influence of calcium carbonate and charcoal application on aggregation processes and organic matter retention at the silt-size scale

    NASA Astrophysics Data System (ADS)

    Asefaw Berhe, Asmeret; Kaiser, Michael; Ghezzehei, Teamrat; Myrold, David; Kleber, Markus

    2013-04-01

    The effectiveness of charcoal and calcium carbonate applications to improve soil conditions has been well documented. However, their influence on the formation of silt-sized aggregates and the amount and protection of associated organic matter (OM) against microbial decomposition is still largely unknown. For sustainable management of agricultural soils, silt-sized aggregates (2-53 µm) are of particularly large importance because they store up to 60% of soil organic carbon with mean residence times between 70 and 400 years. The objectives are i) to analyze the ability of CaCO3 and/or charcoal application to increase the amount of silt-sized aggregates and associated OM, ii) vary soil mineral conditions to establish relevant boundary conditions for amendment-induced aggregation processes, iii) to determine how amendment-induced changes in formation of silt-sized aggregates relate to microbial decomposition of OM. We set up artificial high reactive (HR, clay: 40%, sand: 57%, OM: 3%) and low reactive soils (LR, clay: 10%, sand: 89%, OM: 1%) and mixed them with charcoal (CC, 1%) and/or calcium carbonate (Ca, 0.2%). The samples were adjusted to a water potential of 0.3 bar and sub samples were incubated with microbial inoculum (MO). After a 16-weeks aggregation experiment, size fractions were separated by wet-sieving and sedimentation. Since we did not use mineral compounds in the artificial mixtures within the size range of 2 to 53 µm, we consider material recovered in this fraction as silt-sized aggregates, which was confirmed by SEM analyses. For the LR mixtures, we detected increasing N concentrations within the 2-53 µm fractions of the charcoal amended samples (CC, CC+Ca, and CC+Ca+MO) as compared to the Control sample with the strongest effect for the CC+Ca+MO sample. This indicates an association of N-containing microbial derived OM with silt-sized aggregates. For the charcoal amended LR and HR mixtures, the C concentrations of the 2-53 µm fractions are

  10. Acute Kidney Injury Predicts Mortality after Charcoal Burning Suicide

    PubMed Central

    Chen, Yu-Chin; Tseng, Yi-Chia; Huang, Wen-Hung; Hsu, Ching-Wei; Weng, Cheng-Hao; Liu, Shou-Hsuan; Yang, Huang-Yu; Chen, Kuan-Hsin; Chen, Hui-Ling; Fu, Jen-Fen; Lin, Wey-Ran; Wang, I-Kuan; Yen, Tzung-Hai

    2016-01-01

    A paucity of literature exists on risk factors for mortality in charcoal burning suicide. In this observational study, we analyzed the data of 126 patients with charcoal burning suicide that seen between 2002 and 2013. Patients were grouped according to status of renal damage as acute kidney injury (N = 49) or non-acute kidney injury (N = 77). It was found that patients with acute kidney injury suffered severer complications such as respiratory failure (P = 0.002), myocardial injury (P = 0.049), hepatic injury (P < 0.001), rhabdomyolysis (P = 0.045) and out-of-hospital cardiac arrest (P = 0.028) than patients without acute kidney injury. Moreover, patients with acute kidney injury suffered longer hospitalization duration (16.9 ± 18.3 versus 10.7 ± 10.9, P = 0.002) and had higher mortality rate (8.2% versus 0%, P = 0.011) than patients without injury. In a multivariate Cox regression model, it was demonstrated that serum creatinine level (P = 0.019) and heart rate (P = 0.022) were significant risk factors for mortality. Finally, Kaplan-Meier analysis revealed that patients with acute kidney injury suffered lower cumulative survival than without injury (P = 0.016). In summary, the overall mortality rate of charcoal burning suicide population was 3.2%, and acute kidney injury was a powerful predictor of mortality. Further studies are warranted. PMID:27430168

  11. Acute Kidney Injury Predicts Mortality after Charcoal Burning Suicide.

    PubMed

    Chen, Yu-Chin; Tseng, Yi-Chia; Huang, Wen-Hung; Hsu, Ching-Wei; Weng, Cheng-Hao; Liu, Shou-Hsuan; Yang, Huang-Yu; Chen, Kuan-Hsin; Chen, Hui-Ling; Fu, Jen-Fen; Lin, Wey-Ran; Wang, I-Kuan; Yen, Tzung-Hai

    2016-01-01

    A paucity of literature exists on risk factors for mortality in charcoal burning suicide. In this observational study, we analyzed the data of 126 patients with charcoal burning suicide that seen between 2002 and 2013. Patients were grouped according to status of renal damage as acute kidney injury (N = 49) or non-acute kidney injury (N = 77). It was found that patients with acute kidney injury suffered severer complications such as respiratory failure (P = 0.002), myocardial injury (P = 0.049), hepatic injury (P < 0.001), rhabdomyolysis (P = 0.045) and out-of-hospital cardiac arrest (P = 0.028) than patients without acute kidney injury. Moreover, patients with acute kidney injury suffered longer hospitalization duration (16.9 ± 18.3 versus 10.7 ± 10.9, P = 0.002) and had higher mortality rate (8.2% versus 0%, P = 0.011) than patients without injury. In a multivariate Cox regression model, it was demonstrated that serum creatinine level (P = 0.019) and heart rate (P = 0.022) were significant risk factors for mortality. Finally, Kaplan-Meier analysis revealed that patients with acute kidney injury suffered lower cumulative survival than without injury (P = 0.016). In summary, the overall mortality rate of charcoal burning suicide population was 3.2%, and acute kidney injury was a powerful predictor of mortality. Further studies are warranted. PMID:27430168

  12. Measurement for Work. Teaching Guide and Sample Learning Activities.

    ERIC Educational Resources Information Center

    Angel, Margo; Bolton, Chris

    This document is intended to help Australian technical and further education instructors in New South Wales (TAFE NSW) identify teaching principles and learning activities that they can use to help adult learners master the mathematics processes, knowledge, and skills needed to perform basic measurement tasks in today's workplace. The materials…

  13. Detection of hidden pre-industrial charcoal kilns by high-resolution LIDAR

    NASA Astrophysics Data System (ADS)

    Raab, Thomas; Raab, Alexandra; Nicolay, Alexander; Takla, Melanie; Rösler, Horst; Bönisch, Eberhard

    2013-04-01

    Over the last decade, systematic archaeological excavations in the open-cast mine Jänschwalde (Brandenburg, Germany) have revealed one of the largest, archaeologically excavated pre-industrial charcoal production area in Central Europe. Many of the charcoal kiln relics are easy to detect by survey as they lie close to the surface and charcoal pieces hint on their existence. In the excavations the remains of the charcoal kilns are distinct, black circles in the light-coloured sands. To date, in the former Königlich-Taubendorfer Forst c. 800 remains of charcoal hearths have been excavated and documented by archaeologists in an area of about 20 km2. Further c. 300 charcoal hearths are prospected by survey. Unfortunately, the spatial information about the charcoal kiln sites in Lower Lusatia (and elsewhere) is incomplete since we only have data from the archaeological excavation and prospection in the directly affected mining district. To fill this gap, we decided to test the applicability of Airborne Laser Scanning (ALS) data for charcoal kiln prospection. The particularly improved quality of the recent high-resolution light detection and ranging (LIDAR) data enabled the computer-aided detection of charcoal kilns and their evaluation using a geographical information system (GIS). Following data processing, the charcoal kilns are visible as buttons-like shapes in the shaded-relief maps (SRM). The characteristic shapes arise because the kiln plates are some centimetres to decimetres higher than the ditches around them. Numerous ground checks confirmed the applicability of the prospection by ALS data. But, we also assume that c. 10% of the charcoal kilns remain unidentified. A 26.6 km2 study area in the Tauerscher Forst, a forest about 10 km northwest of the open-cast mine Jänschwalde, was selected for prospection using a 1 m resolution ALS data set from the year 2011. Today, the area is forested with pine, and no archaeological excavation has been carried out so far

  14. A synthesis of parameters related to the binding of neutral organic compounds to charcoal.

    PubMed

    Hale, Sarah E; Arp, Hans Peter H; Kupryianchyk, Darya; Cornelissen, Gerard

    2016-02-01

    The sorption strength of neutral organic compounds to charcoal, also called biochar was reviewed and related to charcoal and compound properties. From 29 studies, 507 individual Freundlich sorption coefficients were compiled that covered the sorption strength of 107 organic contaminants. These sorption coefficients were converted into charcoal-water distribution coefficients (K(D)) at aqueous concentrations of 1 ng/L, 1 µg/L and 1 mg/L. Reported log K(D) values at 1 µg/L varied from 0.38 to 8.25 across all data. Variation was also observed within the compound classes; pesticides, herbicides and insecticides, PAHs, phthalates, halogenated organics, small organics, alcohols and PCBs. Five commonly reported variables; charcoal production temperature T, surface area SA, H/C and O/C ratios and organic compound octanol-water partitioning coefficient, were correlated with KD values using single and multiple-parameter linear regressions. The sorption strength of organic compounds to charcoals increased with increasing charcoal production temperature T, charcoal SA and organic pollutant octanol-water partitioning coefficient and decreased with increasing charcoal O/C ratio and charcoal H/C ratio. T was found to be correlated with SA (r(2) = 0.66) and O/C (r(2) = 0.50), particularly for charcoals produced from wood feedstocks (r(2) = 0.73 and 0.80, respectively). The resulting regression: log K(D)=(0.18 ± 0.06) log K(ow) + (5.74 ± 1.40) log T + (0.85 ± 0.15) log SA + (1.60 ± 0.29) log OC + (-0.89 ± 0.20) log HC + (-13.20 ± 3.69), r(2) = 0.60, root mean squared error = 0.95, n = 151 was obtained for all variables. This information can be used as an initial screening to identify charcoals for contaminated soil and sediment remediation. PMID:26347927

  15. Sample Heat, Activity, Reactivity, and Dose Analysis for Safety Analysis of Irradiations in a Research Reactor.

    1987-12-01

    SHARDA is a program for assessing sample heating rates, activities produced and reactivity load caused while irradiating a small sample in a well thermalized research reactor like CIRUS. It estimates the sample cooling or lead shielding requirements to limit the gamma-ray dose rates due to the irradiated sample within permissible levels.

  16. Measurement of radon potential from soil using a special method of sampling

    NASA Astrophysics Data System (ADS)

    Cosma, Constantin; Papp, Botond; Moldovan, Mircea; Cosma, Victor; Cindea, Ciprian; Suciu, Liviu; Apostu, Adelina

    2010-10-01

    Soil radon gas and/or its exhalation rate are used as indicators for some applications, such as uranium exploration, indoor radon concentration, seismic activity, location of subsurface faults, etc., and also in the studies where the main interest is the field verification of radon transport models. This work proposes a versatile method for the soil radon sampling using a special manner of pumping. The soil gas is passed through a column of charcoal by using passive pumping. A plastic bottle filled with water is coupled to an activated charcoal column and the flow of water through an adjustable hole made at the bottom of bottle assures a controlled gas flow from the soil. The results obtained for the activity of activated charcoal are in the range of 20-40 kBq/m3, for a depth of approximately 0.8 m. The results obtained by this method were confirmed by simultaneous measurements using LUK 3C device for soil radon measurements. Possible applications for the estimation of radon soil potential are discussed.

  17. Concentrations and bioaccessibilities of trace elements in barbecue charcoals.

    PubMed

    Sharp, Annabel; Turner, Andrew

    2013-11-15

    Total and bioaccessible concentrations of trace elements (Al, As, Cd, Cu, Fe, Hg, Mn, Ni, Pb and Zn) have been measured in charcoals from 15 barbecue products available from UK retailers. Total concentrations (available to boiling aqua regia) were greater in briquetted products (with mean concentrations ranging from 0.16 μg g(-1) for Cd to 3240 μg g(-1) for Al) than in lumpwoods (0.007 μg g(-1) for Cd to 28 μg g(-1) for Fe), presumably because of the use of additives and secondary constituents (e.g. coal) in the former. On ashing, and with the exception of Hg, elemental concentrations increased by factors ranging from about 1.5 to 50, an effect attributed to the combustion of organic components and offset to varying extents by the different volatilities of the elements. Concentrations in the ashed products that were bioaccessible, or available to a physiologically based extraction test (PBET) that simulates, successively, the chemical conditions in the human stomach and intestine, exhibited considerable variation among the elements studied. Overall, however, bioaccessible concentrations relative to corresponding total concentrations were greatest for As, Cu and Ni (attaining 100% in either or both simulated PBET phases in some cases) and lowest for Pb (generally <1% in both phases). A comparison of bioaccessible concentrations in ashed charcoals with estimates of daily dietary intake suggest that Al and As are the trace elements of greatest concern to human health from barbecuing. PMID:24140519

  18. Spatial analysis of charcoal kiln remains in the former royal forest district Tauer (Lower Lusatia, North German Lowlands)

    NASA Astrophysics Data System (ADS)

    Raab, Alexandra; Schneider, Anna; Bonhage, Alexander; Takla, Melanie; Hirsch, Florian; Müller, Frank; Rösler, Horst; Heußner, Karl-Uwe

    2016-04-01

    Archaeological excavations have revealed more than thousand charcoal kiln remains (CKRs) in the prefield of the active opencast lignite mine Jänschwalde, situated about 150 km SE of Berlin (SE Brandenburg, Germany). The charcoal was mainly produced for the ironwork Peitz nearby, which operated from the 16th to the mid-19th centuries. In a first approach, to estimate the dimension of the charcoal production, CKRs were mapped on shaded-relief maps (SRMs) derived from high-resolution LiDAR data (Raab et al. 2015). Subsequently, for a selected test area, identified CKRs on the SRMs were compared with archaeologically excavated CKRs in the field. This survey showed a considerably number of falsely detected sites. Therefore, the data was critically re-evaluated using additional relief visualisations. Further, we extended the CKR mapping to areas which are not archaeologically investigated. The study area, the former royal forest district Tauer, consists of two separate areas: the Tauersche Heide (c. 96 km2 area) N of Peitz and the area Jänschwalde (c. 32 km2 area) NE of Peitz. The study area is characterized by a flat topography. Different former and current anthropogenic uses (e.g., military training, solar power plant, forestry measures) have affected the study area, resulting in extensive disturbances of the terrain surface. The revised CKR abundance in the study area Jänschwalde was considerably smaller than the numbers produced by our first approach. Further, the CKR mapping revealed, that a total record of the CKRs is not possible for various reasons. Despite these limitations, a solid database can be provided for a much larger area than before. Basic statistic parameters of the CKR diameters and all comparative statistical tests were calculated using SPSS. To detect underlying spatial relationships in the CKR site distribution, we applied the Getis-Ord Gi* statistic, a method to test for local spatial autocorrelation between neighbouring sites. The test is

  19. Soybean Seed Composition in Cultivars Differing in Resistance to Charcoal Rot (Macrophomina phaseolina)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean [Glycine max (L) Merr.] cultivars of maturity group (MG) IV were selected based on their susceptibility to charcoal rot disease caused by a soilborne fungus (Macrophomina phaseolina). Seed composition and nitrogen fixation in soybean has not been well investigated under charcoal rot infestat...

  20. Digital image processing applications in the ignition and combustion of char/coal particles

    SciTech Connect

    Annamalai, K.; Kharbat, E.; Goplakrishnan, C.

    1992-12-01

    Digital image processing, is employed in this remarch study in order to visually investigate the ignition and combustion characteristics of isolated char/coal particles as well as the effect of interactivecombustion in two-particle char/coal arrays. Preliminary experiments are conducted on miniature isolated candles as well as two-candle arrays.

  1. Carbon sequestration and fertility after centennial time scale incorporation of charcoal into soil.

    PubMed

    Criscuoli, Irene; Alberti, Giorgio; Baronti, Silvia; Favilli, Filippo; Martinez, Cristina; Calzolari, Costanza; Pusceddu, Emanuela; Rumpel, Cornelia; Viola, Roberto; Miglietta, Franco

    2014-01-01

    The addition of pyrogenic carbon (C) in the soil is considered a potential strategy to achieve direct C sequestration and potential reduction of non-CO2 greenhouse gas emissions. In this paper, we investigated the long term effects of charcoal addition on C sequestration and soil physico-chemical properties by studying a series of abandoned charcoal hearths in the Eastern Alps of Italy established in the XIX century. This natural setting can be seen as an analogue of a deliberate experiment with replications. Carbon sequestration was assessed indirectly by comparing the amount of pyrogenic C present in the hearths (23.3±4.7 kg C m(-2)) with the estimated amount of charcoal that was left on the soil after the carbonization (29.3±5.1 kg C m(-2)). After taking into account uncertainty associated with parameters' estimation, we were able to conclude that 80±21% of the C originally added to the soil via charcoal can still be found there and that charcoal has an overall Mean Residence Time of 650±139 years, thus supporting the view that charcoal incorporation is an effective way to sequester atmospheric CO2. We also observed an overall change in the physical properties (hydrophobicity and bulk density) of charcoal hearth soils and an accumulation of nutrients compared to the adjacent soil without charcoal. We caution, however, that our site-specific results should not be generalized without further study. PMID:24614647

  2. Rapid spread of suicide by charcoal burning from 2007 to 2011 in Korea.

    PubMed

    Lee, Ah-Rong; Ahn, Myung Hee; Lee, Tae Yeop; Park, Subin; Hong, Jin Pyo

    2014-11-30

    Despite rapid increase of suicide by charcoal burning within 5 years, little is known about the characteristics of charcoal burning suicide in Korea. This study aimed to examine the trends and risk factors in the spread of suicide using this method. We identified an association between media reporting of suicide by charcoal burning and its incidence. Data on suicide from 2007 to 2011 were obtained from the Korean National Statistical Office. Cross-correlation analysis was used. Increasing incidence of suicide by charcoal burning was correlated with higher education levels, male sex, and the latter half of the year. Victims of charcoal burning suicide were more likely to be young, male, single, highly educated, professional, urban-based, and to die between October and December. Internet reports of suicide via charcoal burning tended to precede the increased incidence of suicide using this method, but only during the early period of the suicide epidemic. Our findings suggest that one episode of heavy media coverage of a novel method, such as charcoal burning, is sufficient to increase the prevalence of suicide by that method even after media coverage decreases. These findings are expected to contribute to the prevention of increasing rates of suicide by charcoal burning. PMID:25048757

  3. Water adsorption on charcoal: New approach in experimental studies and data representation

    SciTech Connect

    Geynisman, M.; Walker, R.

    1991-08-01

    The experimental apparatus was built to study the H{sub 2}O adsorption on charcoal at very low concentrations and collect the data in the form of isosteres. Experimental method is discussed and the global three-dimensional fit is constructed to predict the post-regeneration conditions of charcoal absorbers. 11 refs.

  4. ESTIMATION OF EMISSIONS FROM CHARCOAL LIGHTER FLUID AND REVIEW OF ALTERNATIVES

    EPA Science Inventory

    The report gives results of an evaluation of emissions of volatile organic compounds (VOCs) from charcoal lighter fluid, a consumer product consisting entirely of volatile constituents. An estimated 46,250 tons (42,000 Mg) of charcoal lighter fluid is used in the U.S. each year. ...

  5. Potassium and phosphorus effects on disease severity of charcoal rot of soybean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of potassium (K) and phosphorus (P) fertilizers on charcoal rot of soybean [Glycine max (L.) Merr.] are unknown. Therefore, the severity of charcoal rot was studied at five levels of K (0, 37, 75, 111 and 149 kg K ha-1) and a level that was equal to the recommended fertilizer applicatio...

  6. Potassium and Phosphorus effects on disease severity of charcoal rot of soybean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of potassium (K) and phosphorus (P) fertilizers on charcoal rot of soybean [Glycine max (L.) Merr.] are unknown. Therefore, the severity of charcoal rot was studied at five levels of K (0, 37, 75, 111 and 149 kg K ha-1) and a level that was equal to the recommended fertilizer applicatio...

  7. The effect of weathering on charcoal filter performance. 1; The adsorption and desorption behavior of contaminants

    SciTech Connect

    Wren, J.C.; Moore, C.J. )

    1991-05-01

    This paper reports on triethylenediamine (TEDA) impregnated charcoals, used in nuclear reactors to safeguard against the release of airborne radioiodine, which show high efficiency under various reactor operation and accident conditions when the are new. However, during normal operation, charcoal filters are continuously degraded (or weathered) due to the adsorption of moisture and other air contaminants. The effect of weathering on the efficiency of charcoal for removing radioiodine is of great interest. The results of a study on the adsorption behavior of various contaminants NO{sub 2}, SO{sub 2} 2-butanone (methyl-ethyl ketone (MEK)) and NH{sub 3} on TEDA charcoal are presented. This study is an attempt to characterize and quantify the weathering process of TEDA charcoal by these contaminants. The adsorption and desorption of characteristics of these contaminants range from completely irreversible (NO{sub 2}) to completely reversible (NH{sub 3}). The effect of absorbed water (or humidity) on absorption is different for each contaminant. Absorbed water increases the absorption rate and capacity of TEDA charcoal for NO{sub 2}. However, it appears that SO{sub 2} is absorbed as H{sub 2}SO{sub 4} on the wet charcoal. Absorbed water slightly reduces the adsorption capacity of the charcoal for MEK, but does not affect the absorption of NH{sub 3}.

  8. Effects of directed fungicides sprays and potash form on charcoal rot of soybeans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Evaluation of fungicides to control charcoal rot of soybean was conducted in a field planted annually to soybean or snap bean since 2002 with moderate to high seedling disease losses to charcoal rot. Treatments were applied on 18 Jul at 60 psi and on 7 Aug at 80 psi using a high-pressure hydraulic ...

  9. Carbon Sequestration and Fertility after Centennial Time Scale Incorporation of Charcoal into Soil

    PubMed Central

    Criscuoli, Irene; Alberti, Giorgio; Baronti, Silvia; Favilli, Filippo; Martinez, Cristina; Calzolari, Costanza; Pusceddu, Emanuela; Rumpel, Cornelia; Viola, Roberto; Miglietta, Franco

    2014-01-01

    The addition of pyrogenic carbon (C) in the soil is considered a potential strategy to achieve direct C sequestration and potential reduction of non-CO2 greenhouse gas emissions. In this paper, we investigated the long term effects of charcoal addition on C sequestration and soil physico-chemical properties by studying a series of abandoned charcoal hearths in the Eastern Alps of Italy established in the XIX century. This natural setting can be seen as an analogue of a deliberate experiment with replications. Carbon sequestration was assessed indirectly by comparing the amount of pyrogenic C present in the hearths (23.3±4.7 kg C m−2) with the estimated amount of charcoal that was left on the soil after the carbonization (29.3±5.1 kg C m−2). After taking into account uncertainty associated with parameters’ estimation, we were able to conclude that 80±21% of the C originally added to the soil via charcoal can still be found there and that charcoal has an overall Mean Residence Time of 650±139 years, thus supporting the view that charcoal incorporation is an effective way to sequester atmospheric CO2. We also observed an overall change in the physical properties (hydrophobicity and bulk density) of charcoal hearth soils and an accumulation of nutrients compared to the adjacent soil without charcoal. We caution, however, that our site-specific results should not be generalized without further study. PMID:24614647

  10. URINARY MUTAGENICITY IN CHARCOAL WORKERS: A CROSS-SECTIONAL STUDY IN NORTHEASTERN BRAZIL

    EPA Science Inventory

    Urinary Mutagenicity in charcoal workers: a cross-sectional study in northeastern Brazil

    Charcoal production by wood carbonization is an ancient process that has changed little since the Bronze Age. Its production in large scale is necessary to sustain some steel and pig...

  11. Autoclave inactivation of infectious radioactive laboratory waste contained within a charcoal filtration system.

    PubMed

    Stinson, M C; Green, B L; Marquardt, C J; Ducatman, A M

    1991-07-01

    A model system was developed previously for disposal of solid laboratory waste that is both radioactive and heat sensitive, e.g., HIV. A double polypropylene bag with charcoal vent filter and absorbent was designed to meet requirements for both steam sterilization and disposal as solid radioactive waste. Earlier work demonstrated the effective containment of radioactive gases by the filter and inactivation of organisms as heat sensitive as HIV. We sought to broaden the application of this model to ensure inactivation of microorganisms that are more heat resistant than HIV. The efficacy of steam sterilization using water or solutions of iodophor, hypochlorite, or hydrogen peroxide was studied under constant temperature and time conditions. The systems were monitored with internal probes, physical, chemical, and biological indicators. Biological indicators documented inactivation when bags containing hydrogen peroxide (3%) were autoclaved for 60 min at 121 degrees C. Synergistic activity between hydrogen peroxide and autoclave conditions significantly reduced processing time. PMID:2061040

  12. Autoclave inactivation of infectious radioactive laboratory waste contained within a charcoal filtration system

    SciTech Connect

    Stinson, M.C.; Green, B.L.; Marquardt, C.J.; Ducatman, A.M. )

    1991-07-01

    A model system was developed previously for disposal of solid laboratory waste that is both radioactive and heat sensitive, e.g., HIV. A double polypropylene bag with charcoal vent filter and absorbent was designed to meet requirements for both steam sterilization and disposal as solid radioactive waste. Earlier work demonstrated the effective containment of radioactive gases by the filter and inactivation of organisms as heat sensitive as HIV. The authors sought to broaden the application of this model to ensure inactivation of microorganisms that are more heat resistant than HIV. The efficacy of steam sterilization using water or solutions of iodophor, hypochlorite, or hydrogen peroxide was studied under constant temperature and time conditions. The systems were monitored with internal probes, physical, chemical, and biological indicators. Biological indicators documented inactivation when bags containing hydrogen peroxide (3%) were autoclaved for 60 min at 121C. Synergistic activity between hydrogen peroxide and autoclave conditions significantly reduced processing time.

  13. Molecular Marker Approach on Characterizing and Quantifying Charcoal in Environmental Media

    NASA Astrophysics Data System (ADS)

    Kuo, L.; Herbert, B. E.; Louchouarn, P.

    2006-12-01

    Black carbon (BC) is widely distributed in natural environments including soils, sediments, freshwater, seawater and the atmosphere. It is produced mostly from the incomplete combustion of fossil fuels and vegetation. In recent years, increasing attention has been given to BC due to its potential influence in many biogeochemical processes. In the environment, BC exists as a continuum ranging from partly charred plant materials, charcoal residues to highly condensed soot and graphite particles. The heterogeneous nature of black carbon means that BC is always operationally-defined, highlighting the need for standard methods that support data comparisons. Unlike soot and graphite that can be quantified with well-established methods, it is difficult to directly quantify charcoal in geologic media due to its chemical and physical heterogeneity. Most of the available charcoal quantification methods detect unknown fractions of the BC continuum. To specifically identify and quantify charcoal in soils and sediments, we adopted and validated an innovative molecular marker approach that quantifies levoglucosan, a pyrogenic derivative of cellulose, as a proxy of charcoal. Levoglucosan is source-specific, stable and is able to be detected at low concentrations using gas chromatograph-mass spectrometer (GC-MS). In the present study, two different plant species, honey mesquite and cordgrass, were selected as the raw materials to synthesize charcoals. The lab-synthesize charcoals were made under control conditions to eliminate the high heterogeneity often found in natural charcoals. The effects of two major combustion factors, temperature and duration, on the yield of levoglucosan were characterized in the lab-synthesize charcoals. Our results showed that significant levoglucosan production in the two types of charcoal was restricted to relatively low combustion temperatures (150-350 degree C). The combustion duration did not cause significant differences in the yield of

  14. Baking sunflower hulls within an aluminum envelope in a common laboratory oven yields charcoal

    PubMed Central

    Arnal, Pablo Maximiliano

    2015-01-01

    Charcoals have been widely used by scientist to research the removal of contaminants from water and air. One key feature of charcoal is that it keeps macropores from the parent material – though anisotropically contracted – and can even develop meso- and micropores. However, the controlled thermochemical conversion of biomass into charcoal at laboratory scale normally requires special setups which involve either vacuum or inert gas. Those setups may not be affordable in research groups or educational institutions where the research of charcoals would be highly welcome. In this work, I propose a simple and effective method to steer the thermochemical process that converts sunflower hulls (SFH) into charcoal with basic laboratory resources. The carbonization method: • Place SFH in an airtight aluminum envelope. • Thermally treat SFH within the envelope in a common laboratory oven. • Open the envelope to obtain the carbonized sunflower hulls. PMID:26150989

  15. Baking sunflower hulls within an aluminum envelope in a common laboratory oven yields charcoal.

    PubMed

    Arnal, Pablo Maximiliano

    2015-01-01

    Charcoals have been widely used by scientist to research the removal of contaminants from water and air. One key feature of charcoal is that it keeps macropores from the parent material - though anisotropically contracted - and can even develop meso- and micropores. However, the controlled thermochemical conversion of biomass into charcoal at laboratory scale normally requires special setups which involve either vacuum or inert gas. Those setups may not be affordable in research groups or educational institutions where the research of charcoals would be highly welcome. In this work, I propose a simple and effective method to steer the thermochemical process that converts sunflower hulls (SFH) into charcoal with basic laboratory resources. The carbonization method: •Place SFH in an airtight aluminum envelope.•Thermally treat SFH within the envelope in a common laboratory oven.•Open the envelope to obtain the carbonized sunflower hulls. PMID:26150989

  16. Interactive effects of biochar ageing in soils related to feedstock, pyrolysis temperature, and historic charcoal production.

    NASA Astrophysics Data System (ADS)

    Heitkötter, Julian; Marschner, Bernd

    2015-04-01

    particles, extractable DOC was lower and less aromatic than in the adjacent control soil, likely due to strong sorption of dissolved organic matter (DOM) onto charcoal particles. We suggest that higher sorption of DOM onto the surface of biochar in the control soil provided additional acid functional groups and thus increased the surface charge to a greater extent than in the DOC poorer kiln soil. Hence, biochars incubated in the kiln soil showed less changes in CEC and surface acidity. Higher availability of DOM in the control soil could also stimulate microbial activity to a larger extent, resulting in higher oxidation rates of biochars incubated in the control soil.

  17. Towards an inventory of historic charcoal production fields in Brandenburg, Germany

    NASA Astrophysics Data System (ADS)

    Schneider, Anna; Takla, Melanie; Raab, Alexandra; Raab, Thomas; Bonhage, Alexander; Hirsch, Florian; Rösler, Horst

    2015-04-01

    The historic production of charcoal is an important component of the late Holocene fire history for many landscapes. Charcoal production can have numerous effects on ecosystems, e.g., through changes in forest area and structure, or through the effects of pyrolysis, charcoal and ash addition to soils. To assess such effects, it is necessary to understand the spatial extent and patterns of historic charcoal production, which has so far hardly been approached for the Northern European Lowlands. In the forefield of the open-cast mine Jänschwalde (north of Cottbus, Germany), archaeological excavations have revealed one of the largest charcoal production fields described so far. For this area, we applied and evaluated different methods for mapping the spatial distribution of charcoal kiln remains. Based on our results from this exceptionally well-described charcoal production field, we attempted to detect and map other large occurrences of charcoal kiln remains in the state of Brandenburg. For the mine forefield, archaeological excavations provide certain and exact information on kiln site location and geometry. Using airborne laser scanning elevation models, the mapping of kiln sites could be extended to areas beyond the mine forefield, using a manual digitization for thorough mapping in forest areas north of Cottbus, and an automated mapping approach for detection of kiln sites for additional areas in Brandenburg. Potential areas of large-scale production were identified in a GIS-based analysis of environmental and historic data. By manual digitization from Shaded Relief Maps, more than 5000 kiln sites in an area of 32 km2 were detected in the Jänschwalde mine forefield. First results of mapping for larger areas indicate similar densities, but smaller diameters of kiln sites in other charcoal production fields; and show that charcoal production is a so far underestimated component of the land use history in many parts of the Northern European Lowlands.

  18. Towards an improvement of carbon accounting for wildfires: incorporation of charcoal production into carbon emission models

    NASA Astrophysics Data System (ADS)

    Doerr, Stefan H.; Santin, Cristina; de Groot, Bill

    2015-04-01

    Every year fires release to the atmosphere the equivalent to 20-30% of the carbon (C) emissions from fossil fuel consumption, with future emissions from wildfires expected to increase under a warming climate. Critically, however, part of the biomass C affected by fire is not emitted during burning, but converted into charcoal, which is very resistant to environmental degradation and, thus, contributes to long-term C sequestration. The magnitude of charcoal production from wildfires as a long-term C sink remains essentially unknown and, to the date, charcoal production has not been included in wildfire emission and C budget models. Here we present complete inventories of charcoal production in two fuel-rich, but otherwise very different ecosystems: i) a boreal conifer forest (experimental stand-replacing crown fire; Canada, 2012) and a dry eucalyptus forest (high-intensity fuel reduction burn; Australia 2014). Our data show that, when considering all the fuel components and quantifying all the charcoal produced from each (i.e. bark, dead wood debris, fine fuels), the overall amount of charcoal produced is significant: up to a third of the biomass C affected by fire. These findings indicate that charcoal production from wildfires could represent a major and currently unaccounted error in the estimation of the effects of wildfires in the global C balance. We suggest an initial approach to include charcoal production in C emission models, by using our case study of a boreal forest fire and the Canadian Fire Effects Model (CanFIRE). We also provide recommendations of how a 'conversion factor' for charcoal production could be relatively easily estimated when emission factors for different types of fuels and fire conditions are experimentally obtained. Ultimately, this presentation is a call for integrative collaboration between the fire emission modelling community and the charcoal community to work together towards the improvement of C accounting for wildfires.

  19. Quality assurance guidance for field sampling and measurement assessment plates in support of EM environmental sampling and analysis activities

    SciTech Connect

    Not Available

    1994-05-01

    This document is one of several guidance documents developed by the US Department of Energy (DOE) Office of Environmental Restoration and Waste Management (EM). These documents support the EM Analytical Services Program (ASP) and are based on applicable regulatory requirements and DOE Orders. They address requirements in DOE Orders by providing guidance that pertains specifically to environmental restoration and waste management sampling and analysis activities. DOE 5700.6C Quality Assurance (QA) defines policy and requirements to establish QA programs ensuring that risks and environmental impacts are minimized and that safety, reliability, and performance are maximized. This is accomplished through the application of effective management systems commensurate with the risks imposed by the facility and the project. Every organization supporting EM`s environmental sampling and analysis activities must develop and document a QA program. Management of each organization is responsible for appropriate QA program implementation, assessment, and improvement. The collection of credible and cost-effective environmental data is critical to the long-term success of remedial and waste management actions performed at DOE facilities. Only well established and management supported assessment programs within each EM-support organization will enable DOE to demonstrate data quality. The purpose of this series of documents is to offer specific guidance for establishing an effective assessment program for EM`s environmental sampling and analysis (ESA) activities.

  20. NREL Develops Accelerated Sample Activation Process for Hydrogen Storage Materials (Fact Sheet)

    SciTech Connect

    Not Available

    2010-12-01

    This fact sheet describes NREL's accomplishments in developing a new sample activation process that reduces the time to prepare samples for measurement of hydrogen storage from several days to five minutes and provides more uniform samples. Work was performed by NREL's Chemical and Materials Science Center.

  1. Study of activation of metal samples from LDEF-1 and Spacelab-2

    NASA Technical Reports Server (NTRS)

    Laird, C. E.

    1991-01-01

    The activation of metal samples and other material orbited onboard the Long Duration Exposure Facility (LDEF) and Spacelab-2 were studied. Measurements of the radioactivities of spacecraft materials were made, and corrections for self-absorption and efficiency were calculated. Activation cross sections for specific metal samples were updated while cross sections for other materials were tabulated from the scientific literature. Activation cross sections for 200 MeV neutrons were experimentally determined. Linear absorption coefficients, half lives, branching ratios and other pertinent technical data needed for LDEF sample analyses were tabulated. The status of the sample counting at low background facilities at national laboratories is reported.

  2. Neutron Activation Analysis of Soil Samples from Different Parts of Edirne in Turkey*

    NASA Astrophysics Data System (ADS)

    Zaim, N.; Dogan, C.; Camtakan, Z.

    2016-05-01

    The concentrations of constituent elements were determined in soil samples collected from different parts of the Maritza Basin, Edirne, Turkey. Neutron activation analysis, an extremely accurate technique, and the comparator method (using a standard) were applied for the first time in this region. After preparing the soil samples for neutron activation analysis, they were activated with thermal neutrons in a nuclear reactor, TRIGA-MARK II, at Istanbul Technical University. The activated samples were analyzed using a high-efficiency high-purity germanium detector, and gamma spectrometry was employed to determine the elemental concentration in the samples. Eight elements (chromium, manganese, cobalt, zinc, arsenic, molybdenum, cadmium, and barium) were qualitatively and quantitatively identified in 36 samples. The concentrations of some elements in the soil samples were high compared with values reported in the literature.

  3. [Caring for families of charcoal-burning suicide patients].

    PubMed

    Pien, Feng-Chen; Feng, Hsin-Pei; Tzeng, Wen-Chii

    2013-12-01

    Charcoal-burning is the second major cause of suicide death in Taiwan. Predicting the variable damage and sequelae in this suicide mode is difficult due to the rapid combination of carbon monoxide with red blood cells. Delayed neuropsychological sequelae (DNS) may result in significantly extended recovery times, causing additional stress to the family. Nurses may help increase family understanding and support and guide family members to more positive intra-family interactions, shared perspectives on the recovery process, and resource seeking behavior by depicting subsequent family life and helping the entire family develop coping strategies those allow all members to effect cognitive, emotional and behavioral change. This result may help families of attempted suicide individuals recover successfully. PMID:24310557

  4. Mitochondrial Respiration Chain Enzymatic Activities in the Human Brain: Methodological Implications for Tissue Sampling and Storage.

    PubMed

    Ronsoni, Marcelo Fernando; Remor, Aline Pertile; Lopes, Mark William; Hohl, Alexandre; Troncoso, Iris H Z; Leal, Rodrigo Bainy; Boos, Gustavo Luchi; Kondageski, Charles; Nunes, Jean Costa; Linhares, Marcelo Neves; Lin, Kátia; Latini, Alexandra Susana; Walz, Roger

    2016-04-01

    Mitochondrial respiratory chain complexes enzymatic (MRCCE) activities were successfully evaluated in frozen brain samples. Epilepsy surgery offers an ethical opportunity to study human brain tissue surgically removed to treat drug resistant epilepsies. Epilepsy surgeries are done with hemodynamic and laboratory parameters to maintain physiology, but there are no studies analyzing the association among these parameters and MRCCE activities in the human brain tissue. We determined the intra-operative parameters independently associated with MRCCE activities in middle temporal neocortex (Cx), amygdala (AMY) and head of hippocampus (HIP) samples of patients (n = 23) who underwent temporal lobectomy using multiple linear regressions. MRCCE activities in Cx, AMY and HIP are differentially associated to trans-operative mean arterial blood pressure, O2 saturation, hemoglobin, and anesthesia duration to time of tissue sampling. The time-course between the last seizure occurrence and tissue sampling as well as the sample storage to biochemical assessments were also associated with enzyme activities. Linear regression models including these variables explain 13-17 % of MRCCE activities and show a moderate to strong effect (r = 0.37-0.82). Intraoperative hemodynamic and laboratory parameters as well as the time from last seizure to tissue sampling and storage time are associated with MRCCE activities in human samples from the Cx, AMYG and HIP. Careful control of these parameters is required to minimize confounding biases in studies using human brain samples collected from elective neurosurgery. PMID:26586405

  5. Pedometer-Determined Physical Activity and Its Comparison with the International Physical Activity Questionnaire in a Sample of Belgian Adults

    ERIC Educational Resources Information Center

    De Cocker, Katrien; Cardon, Greet; De Bourdeaudhuij, Ilse

    2007-01-01

    Pedometer-determined physical activity (PA) levels in Belgian adults were provided and compared to PA scores reported in the International Physical Activity Questionnaire (IPAQ). The representative sample (N = 1,239) of the Belgian population took on average 9,655 (4,526) steps/day. According to pedometer indices 58.4% were insufficiently active.…

  6. Charcoal emissions as a source of CO and carcinogenic PAH in mainstream narghile waterpipe smoke.

    PubMed

    Monzer, Bassel; Sepetdjian, Elizabeth; Saliba, Najat; Shihadeh, Alan

    2008-09-01

    Burning charcoal is normally placed atop the tobacco to smoke the narghile waterpipe. We investigated the importance of charcoal as a toxicant source in the mainstream smoke, with particular attention to two well-known charcoal emissions: carbon monoxide (CO) and polyaromatic hydrocarbons (PAH). CO and PAH yields were compared when a waterpipe was machine smoked using charcoal and using an electrical heating element. The electrical heating element was designed to produce spatial and temporal temperature distributions similar to those measured using charcoal. With a popular type of ma'assel tobacco mixture, and using a smoking regimen consisting of 105 puffs of 530ml volume spaced 17s apart, it was found that approximately 90% of the CO and 75-92% of the 4- and 5-membered ring PAH compounds originated in the charcoal. Greater than 95% of the benzo(a)pyrene in the smoke was attributable to the charcoal. It was also found that the relative proportions of individual PAH species, the "PAH fingerprint", of the mainstream smoke were highly correlated to those extracted from the unburned charcoal (R(2)>0.94). In contrast, there was no correlation between the PAH fingerprint of the electrically heated and charcoal-heated conditions (R(2)<0.02). In addition to inhaling toxicants transferred from the tobacco, such as nicotine, "tar", and nitrosamines, waterpipe smokers thus also inhale large quantities of combustion-generated toxicants. This explains why, despite the generally low temperatures attained in the narghile tobacco, large quantities of CO and PAH have been found in the smoke. PMID:18573302

  7. A facile synthesis of Fe3O4-charcoal composite for the sorption of a hazardous dye from aquatic environment.

    PubMed

    Ahmed, Md Juned K; Ahmaruzzaman, M

    2015-11-01

    Herein, we synthesized Fe3O4-charcoal composite using chemical precipitation technique and utilized it for the sorption of methylene blue from aqueous solution. The synthesized composite was characterized by Infra-red spectroscopy, N2 adsorption-desorption isotherm, X-ray diffraction, selected area electron diffraction, transmission electron microscopy, and vibrating sample magnetometer. The composite depicts absorption bands conforming to Fe-O, -OH, CO, and C-O vibrations. The composite was mesoporous in nature with a surface area of 387.30 m(2) g(-1). The observed diffraction planes correspond to face-centered cubic Fe3O4 and disordered graphitic carbon. The spherical Fe3O4 particles (average diameter ∼13.8 nm) were uniformly distributed in the carbon matrix of the charcoal. The saturation and remanent magnetizations demonstrate its potential for magnetic separation and reuse. The composite showed dye sorption capacities of 97.49 mg g(-1) and 90.85 mg g(-1) in batch and fixed-bed system. Pseudo-second order kinetics and Temkin isotherm best represented the sorption data. The sorption process was endothermic, spontaneous, and administered by electrostatic, π-π dispersive interactions, film, and intraparticle diffusion. Microwave irradiations followed by methanol elution regenerated the dye-loaded composite with nearly no loss in sorption capacity. The recovery of energy and potential utilization of bottom ash enhances the prospective of Fe3O4-charcoal composite for industrial applications. PMID:26320009

  8. Black carbon quantification in charcoal-enriched soils by differential scanning calorimetry

    NASA Astrophysics Data System (ADS)

    Hardy, Brieuc; Cornelis, Jean-Thomas; Leifeld, Jens

    2015-04-01

    Black carbon (BC), the solid residue of the incomplete combustion of biomass and fossil fuels, is ubiquitous in soil and sediments, fulfilling several environmental services such as long-term carbon storage. BC is a particularly important terrestrial carbon pool due to its large residence time compared to thermally unaltered organic matter, which is largely attributed to its aromatic structure. However, BC refers to a wide range of pyrogenic products from partly charred biomass to highly condensed soot, with a degree of aromaticity and aromatic condensation varying to a large extend across the BC continuum. As a result, BC quantification largely depends on operational definitions, with the extraction efficiency of each method varying across the entire BC range. In our study, we investigated the adequacy of differential scanning calorimetry (DSC) for the quantification of BC in charcoal-enriched soils collected in the topsoil of pre-industrial charcoal kilns in forest and cropland of Wallonia, Belgium, where charcoal residues are mixed to uncharred soil organic matter (SOM). We compared the results to the fraction of the total organic carbon (TOC) resisting to K2Cr2O7 oxidation, another simple method often used for BC measurement. In our soils, DSC clearly discriminates SOM from chars. SOM is less thermally stable than charcoal and shows a peak maximum around 295°C. In forest and agricultural charcoal-enriched soils, three peaks were attributed to the thermal degradation of BC at 395, 458 and 523°C and 367, 420 and 502 °C, respectively. In cropland, the amount of BC calculated from the DSC peaks is closely related (slope of the linear regression = 0.985, R²=0.914) to the extra organic carbon content measured at charcoal kiln sites relative to the charcoal-unaffected adjacent soils, which is a positive indicator of the suitability of DSC for charcoal quantification in soil. The first BC peak, which may correspond to highly degraded charcoal, contributes to a

  9. Effects of bagasse-charcoal addition to soil on nitrate leaching in calcaric soils

    NASA Astrophysics Data System (ADS)

    Kameyama, K.; Miyamoto, T.; Shinogi, Y.

    2009-12-01

    Nitrate leaching in soils is often an important aspect in agriculture. Nitrate is leached from the root zone, where plants can utilize them, by surplus rainfall because little nitrate is absorbed by soil colloids. Miyako Island (target area) is located in the subtropical zone and comprised of coral limestone with high permeability. Land surface is covered with calcaric dark red soil that is called “Shimajiri-Maji”. Since the soil has low water- and fertilizer-retaining capacity, fertilizer-derived nitrogen easily leaches from the root zone during surplus rainfall and the nitrogen utilization efficiency of crops is relatively low. Biochars, charcoal produced from pyrolysis of biomass, are known to adsorb dissolved nitrate. Sugarcane bagasse is the main biomass resource on the island because agriculture is the main industry on the island and sugarcane is cultivated in approximately 70% of the farmland. However, the adsorption characteristics of bagasse-charcoals for nitrate have not yet been clarified. The objective of this study was to evaluate the dependency of carbonization temperatures on the nitrate adsorption properties of bagasse-charcoals and the effects of bagasse-charcoal addition to the soil on NO3-N transport in the soil for optimal use of bagasse-charcoal as a soil amendment in Miyako Island. Sugarcane bagasse were air-dried and heated in a batch-type carbonization furnace at five different carbonization temperatures (400, 500, 600, 700 and 800°C) with a holding time of 2 h. Nitrate adsorption by soil and bagasse-charcoals at each carbonization temperature was measured by the batch equilibrium technique. NO3-N transport behavior in charcoal-amended soils (rates of charcoal addition: 0, 5 and 10 wt %) was evaluated in the column experiments. The breakthrough curves of NO3-N concentrations in the effluents from the bottom of the columns were analyzed with a convective-dispersion model. The model described one-dimensional transport of a sorbing solute

  10. NHEXAS PHASE I REGION 5 STUDY--STANDARD OPERATING PROCEDURE--ANALYSIS OF VOLATILE ORGANIC COMPOUNDS FROM CHARCOAL BADGES BY GAS CHROMATOGRAPHY/MASS SPECTROMETRY (RTI/ACS-AP-209-112)

    EPA Science Inventory

    This protocol provides guidelines for determining volatile organic hydrocarbons (VOCs) in air samples by gas chromatography/mass spectrometry (GC/MS). This method is for the analysis of VOCs in air by GC/MS in the selected ion monitoring mode (SIM). Charcoal badge samplers are ex...

  11. Forestry and charcoal burning in the vicinity of the ironwork Peitz (South Brandenburg, Germany) - What do we know from historical and archaeological data?

    NASA Astrophysics Data System (ADS)

    Takla, Melanie; Frank, Müller; Horst, Rösler; Raab, Alexandra; Raab, Thomas

    2014-05-01

    The former royal forest districts around Peitz (South Brandenburg, Germany) were used to produce charcoal for the ironwork Peitz (1554 to 1856). More than 800 archaeologically excavated ground plans of charcoal kilns give evidence of the burning activity in the study area "Jänschwalde Heide" which is only a small part of the whole forest district. The study area in the apron of the active lignite mine Jänschwalde comprises the royal forest "Jänschwalder Heide" and the surrounding community forests. Our study approach combines archaeological research, a GIS-based approach (historical maps, airborne laser scanning (ALS) data, etc.) and archival studies. The charcoal kilns have been registered since 1990 and since 2005 they are systematically excavated and documented. First dendrochronological data reach from the 17th to the 19th century confirming charcoal burning during the operation period of the iron work. Moreover 5000 additional kilns were identified and digitized from Shaded Relief Maps (SRM) created from ALS data (resolution 1p m-2; height accuracy +- 15 cm). A kiln field of such a dimension has not been documented and investigated for the North German Lowlands so far. It raises the question about the effects of charcoal burning on the forests and the landscape during the last three hundred years. Here we present the evaluation of the kiln data with regard to their size, frequency and spatial distribution. Besides the large number, the kilns have also large diameters (modal value 17 m, mean 12,5 m). Outside the boundaries of the royal forest the kilns are smaller and they were probably used to produce charcoal for local handcraft. These findings are compared to historical records from the first forest inventories (18th/19th century) like forest age and area, with historical forest laws and wood consumption data of the iron work. There is growing evidence that despite of the large extent of the kiln field the wood reserves in the forest districts about 1800

  12. Study of proton and neutron activation of metal samples in low Earth orbit

    NASA Technical Reports Server (NTRS)

    Laird, C. E.

    1984-01-01

    The analysis of the gamma-ray spectra taken from samples flown in Spacelab 1; the search for and review of neutron and proton activation cross-sections needed to analyze the results of the Long Duration Exposure Facility (LDEF) activation measurements; additional calculations of neutron induced activation for the LDEF samples; the data analysis plan for the LDEF and Spacelab 2 samples; the measurement of relevant cross-sections with activation of samples of V, Co, In, and Ta at the Indiana University Cyclotron Facility; and the preparation of an extended gamma-ray calibration source through the development of a proper technique to accurately deposit equal quantities of radioactive material onto a large number of point on the source are discussed.

  13. Research of morphology structure and properties of bamboo charcoal acrylic fiber

    NASA Astrophysics Data System (ADS)

    Zhang, Yongjiu; Feng, Aifen

    2015-07-01

    In order to understand the properties of bamboo charcoal acrylic fiber, the tensile properties, friction properties and hygroscopicity of it, the bamboo charcoal acrylic fiber and the ordinary acrylic fiber were tested, compared and analyzed. The burning behaviors of the two kinds of fibers were observed by burning test, and their cross-sectional and longitudinal morphology was observed with scanning electron microscope (SEM). The SEM pictures showed that there are the uneven sizes of microspores on the surface of bamboo charcoal acrylic fiber and in it. It was found that the friction coefficients of the bamboo charcoal acrylic fiber are smaller and its tensile and moisture absorption are better than those of the ordinary acrylic fiber. However, there are no obvious differences of the burning behaviors between the two fibers.

  14. Combustion efficiency and hydrocarbon emissions from charcoal production kilns in the tropics

    SciTech Connect

    Ward, D.E.; Hao, W.M.; Babbitt, R.E.

    1995-12-01

    Charcoal is one of the major energy resources in tropical countries. We investigate the combustion processes in charcoal production kilns in Zambia and Brazil. The Zambian kilns were made of earth and there was sufficient air for combustion inside the kilns. The Brazilian kilns were made of bricks which limited the available oxygen. The combustion efficiency and the concentrations of CO{sub 2}, CO, CH{sub 4}, C{sub 2}-C{sub 6} alkanes and alkenes, and aromatic compounds produced were monitored throughout the combustion processes. The contributions of charcoal production processes to the atmospheric sources of these gases were estimated. The strategies for improving charcoal yield and reducing emissions of carbon-containing compounds are discussed.

  15. Chemical structure of wood charcoal by infrared spectroscopy and multivariate analysis.

    PubMed

    Labbé, Nicole; Harper, David; Rials, Timothy; Elder, Thomas

    2006-05-17

    In this work, the effect of temperature on charcoal structure and chemical composition is investigated for four tree species. Wood charcoal carbonized at various temperatures is analyzed by mid infrared spectroscopy coupled with multivariate analysis and by thermogravimetric analysis to characterize the chemical composition during the carbonization process. The multivariate models of charcoal were able to distinguish between species and wood thermal treatments, revealing that the characteristics of the wood charcoal depend not only on the wood species, but also on the carbonization temperature. This work demonstrates the potential of mid infrared spectroscopy in the whiskey industry, from the identification and classification of the wood species for the mellowing process to the chemical characterization of the barrels after the toasting and charring process. PMID:19127715

  16. Measurement and calculation of the sound absorption coefficient of pine wood charcoal

    NASA Astrophysics Data System (ADS)

    Suh, Jae Gap; Baik, Kyung min; Kim, Yong Tae; Jung, Sung Soo

    2013-10-01

    Although charcoal has been widely utilized for physical therapy and as a deodorant, water purifier, etc. due to its porous features, research on its role as a sound-absorbing material is rarely found. Thus, the sound absorption coefficients of pine wood charcoal were measured using an impedance tube and were compared with the theoretical predictions in the frequency range of 500˜ 5000 Hz. The theory developed in the current study only considers the lowest possible mode propagating along the air channels of the charcoal and shows good agreements with the measurements. As the frequency is increased, the sound absorption coefficients of pine wood charcoals also increase, but are lower than those of other commonly-used sound-absorbing materials.

  17. Analogies Between the Cracking Noise of Ethanol-Dampened Charcoal and Earthquakes.

    PubMed

    Ribeiro, H V; Costa, L S; Alves, L G A; Santoro, P A; Picoli, S; Lenzi, E K; Mendes, R S

    2015-07-10

    We report on an extensive characterization of the cracking noise produced by charcoal samples when dampened with ethanol. We argue that the evaporation of ethanol causes transient and irregularly distributed internal stresses that promote the fragmentation of the samples and mimic some situations found in mining processes. The results show that, in general, the most fundamental seismic laws ruling earthquakes (the Gutenberg-Richter law, the unified scaling law for the recurrence times, Omori's law, the productivity law, and Båth's law) hold under the conditions of the experiment. Some discrepancies were also identified (a smaller exponent in the Gutenberg-Richter law, a stationary behavior in the aftershock rates for long times, and a double power-law relationship in the productivity law) and are related to the different loading conditions. Our results thus corroborate and elucidate the parallel between the seismic laws and fracture experiments caused by a more complex loading condition that also occurs in natural and induced seismicity (such as long-term fluid injection and gas-rock outbursts in mining processes). PMID:26207479

  18. Analogies Between the Cracking Noise of Ethanol-Dampened Charcoal and Earthquakes

    NASA Astrophysics Data System (ADS)

    Ribeiro, H. V.; Costa, L. S.; Alves, L. G. A.; Santoro, P. A.; Picoli, S.; Lenzi, E. K.; Mendes, R. S.

    2015-07-01

    We report on an extensive characterization of the cracking noise produced by charcoal samples when dampened with ethanol. We argue that the evaporation of ethanol causes transient and irregularly distributed internal stresses that promote the fragmentation of the samples and mimic some situations found in mining processes. The results show that, in general, the most fundamental seismic laws ruling earthquakes (the Gutenberg-Richter law, the unified scaling law for the recurrence times, Omori's law, the productivity law, and Båth's law) hold under the conditions of the experiment. Some discrepancies were also identified (a smaller exponent in the Gutenberg-Richter law, a stationary behavior in the aftershock rates for long times, and a double power-law relationship in the productivity law) and are related to the different loading conditions. Our results thus corroborate and elucidate the parallel between the seismic laws and fracture experiments caused by a more complex loading condition that also occurs in natural and induced seismicity (such as long-term fluid injection and gas-rock outbursts in mining processes).

  19. neutron activation analysis using thermochromatography. II. thermochromatographic separation of elements in the analysis of geological samples

    SciTech Connect

    Sattarov, G.; Davydov, A.V.; Khamatov, S.; Kist, A.A.

    1986-07-01

    The use of gas thermochromatography (GTC) in the radioactivation analysis of difficulty soluble samples with a strongly activating substrate is discussed. The effect of sample coarseness and ore type on the rate of extraction of gold and accompanying elements was studied. The limits of detection of 22 elements were compared using neutron activation analysis with GTC and INAA. The analytical parameters of the procedure were estimated.

  20. Salts of the iodine oxyacids in the impregnation of adsorbent charcoal for trapping radioactive methyliodide

    DOEpatents

    Deitz, Victor R.; Blachly, Charles H.

    1977-04-05

    Radioactive iodine and radioactive methyliodide can be more than 99.7 per cent removed from the air stream of a nuclear reactor by passing the air stream through a 2-inch thick filter which is made up of impregnated charcoal prepared by contacting the charcoal with a solution containing KOH, iodine or an iodide, and an oxyacid, followed by contacting with a solution containing a tertiary amine.

  1. A method for detecting breakthrough of organic solvent vapors in a charcoal tube using semiconductor gas sensors

    SciTech Connect

    Hori, Hajime; Noritake, Yuji; Murobushi, Hisako; Higashi, Toshiaki; Tanaka, Isamu

    1999-08-01

    This study developed a method for detecting organic vapors that break through charcoal tubes, using semiconductor gas sensors as a breakthrough detector of vapors. A glass column equipped with two sensors was inserted in Teflon tubing, and air containing organic vapor was introduced at a constant flow rate. After the output signal of the sensors became stable, a charcoal tube was inserted into the tubing at the upstream of the sensors. The resistance of the sensors was collected temporally in an integrated circuit (IC) card. The vapor concentration of the air near the sensors was measured with a gas chromatograph (GC) equipped with a flame ionization detector (FID) at intervals of 5 minutes to obtain the breakthrough curve. When the relative humidity was zero, the output signals of the sensors began to change before the breakthrough point (1% breakthrough time). This tendency was almost the same for methyl acetate, ethyl acetate, isopropyl alcohol (IPA), toluene, and chloroform. For dichloromethane and 1,1,1-trichloroethane, the time when the sensor output signals began to rise was almost the same as the breakthrough point. When the relative humidity was 80 percent, the sensors could also detect many vapors before the breakthrough point, but they could not perceive dichloromethane and chloroform vapors. A personal sampling system with a breakthrough detector was developed and its availability is discussed.

  2. Applied Technology of Bamboo Charcoal to Improvement and Purification of Air Quality

    NASA Astrophysics Data System (ADS)

    Takimoto, Akira; Tada, Yukio; Onishi, Hajime; Fukazawa, Tomohiro

    The use of bamboo charcoal, which is one of the carbon from wood, attracts attention from the viewpoint of the environmental protection. Bamboo charcoal has high adsorption removal ability to various substances. In addition Bamboo charcoal is effective also for the filtration of the suspended solid and the bacterium by the macro pore that originates in the plant frame structure. In present paper, a new concept of gas clean technology by bamboo charcoal and TiO2 with UV light irradiation was proposed. Its system is composed of TiO2-coated bamboo charcoal, TiO2-coated silica gel and UV lamp. Water vapor is adsorbed by bamboo charcoal and fine particles and airborne bacterium are trapped on the surface of it. Trapped contaminant is degraded by TiO2 and UV light. In addition, the degradation is promoted by •OH produced by adsorbed water vapor. The air purification sanitization possibility in high efficiency for this system was clarified.

  3. Experience with improved charcoal and wood stoves for households and institutions in Kenya

    SciTech Connect

    Hyman, E.L.

    1985-01-01

    Efforts at promoting more fuel-efficient charcoal stoves to replace traditional charcoal stoves in Kenya offer some lessons for the dissemination of appropriate technologies. This paper looks at the market-based approach which has made the Kenyan charcoal stoves project a success. Trends in woodfuels (wood and charcoal) consumption in Kenya are identified; the traditional technology for charcoal combustion and the upgraded traditional technologies are described; production achievement and the dissemination and promotion strategy used are examined; and a financial and economic analysis is performed with social, health and environmental effects assessed. Other ways to achieve a more favourable balance between woodfuels consumption and supply are then discussed looking at more efficient charcoal kilns and household woodstoves, improved institutional stoves and increased wood production. The replication potential of the Kenya experiment in other countries is also explored. The lessons learnt from the the Kenya experience concern the relationship between technology, choice and delivery systems as they interact with, economic, institutional, and policy factors. In this case, the design work accepted the traditional technology as a starting point which helped ensure widespread acceptance by households. The potential desirability of relying on local artisans to manufacture consumer durables using existing private sector channels to market these goods is also shown. It also highlights the importance of going beyond a laissez-faire approach and supporting training, demonstration, and publicity to faciliate the workings of the private sector. In the Kenyan case, technology choice was relatively unsubsidized and left ot the preferences of consumers.

  4. Estimation of emissions from charcoal lighter fluid and review of alternatives. Final report

    SciTech Connect

    Campbell, D.L.; Stockton, M.B.

    1990-01-01

    The report gives results of an evaluation of emissions of volatile organic compounds (VOCs) from charcoal lighter fluid, a consumer product consisting entirely of volatile constituents. An estimated 46,250 tons (42,000 Mg) of charcoal lighter fluid is used in the U.S. each year. VOCs contribute to the formation of ozone; therefore, the ozone nonattainment issue has focused attention on VOCs emitted from many sources. VOCs are emitted when charcoal lighter fluid is used, but these emissions are difficult to quantify. Evaporative VOC losses occur from the lighter fluid prior to ignition, and combustion VOC losses occur from burning lighter-fluid-soaked charcoal briquettes. This study evaluates tests conducted to date on charcoal lighter fluid emissions. The information is most complete for evaporative VOC losses. The estimates vary greatly, however, based on the length of time between application of the lighter fluid and ignition. The limited tests conducted to date have not distinguished lighter fluid from charcoal-briquette combustion emissions.

  5. Chemical and Isotopic Thresholds in Charring: Implications for the Interpretation of Charcoal Mass and Isotopic Data.

    PubMed

    Pyle, Lacey A; Hockaday, William C; Boutton, Thomas; Zygourakis, Kyriacos; Kinney, Timothy J; Masiello, Caroline A

    2015-12-15

    Charcoal plays a significant role in the long-term carbon cycle, and its use as a soil amendment is promoted as a C sequestration strategy (biochar). One challenge in this research area is understanding the heterogeneity of charcoal properties. Although the maximum reaction temperature is often used as a gauge of pyrolysis conditions, pyrolysis duration also changes charcoal physicochemical qualities. Here, we introduce a formal definition of charring intensity (CI) to more accurately characterize pyrolysis, and we document variation in charcoal chemical properties with variation in CI. We find two types of responses to CI: either linear or threshold relationships. Mass yield decreases linearly with CI, while a threshold exists across which % C, % N, and δ(15)N exhibit large changes. This CI threshold co-occurs with an increase in charcoal aromaticity. C isotopes do not change from original biomass values, supporting the use of charcoal δ(13)C signatures to infer paleoecological conditions. Fractionation of N isotopes indicates that fire may be enriching soils in (15)N through pyrolytic N isotope fractionation. This influx of "black N" could have a significant impact on soil N isotopes, which we show theoretically using a simple mass-balance model. PMID:26523420

  6. Phanerozoic concentrations of atmospheric oxygen reconstructed from sedimentary charcoal

    NASA Astrophysics Data System (ADS)

    Glasspool, Ian J.; Scott, Andrew C.

    2010-09-01

    Variations of the Earth's atmospheric oxygen concentration (pO2) are thought to be closely tied to the evolution of life, with strong feedbacks between uni- and multicellular life and oxygen. On the geologic timescale, pO2 is regulated by the burial of organic carbon and sulphur, as well as by weathering. Reconstructions of atmospheric O2 for the past 400million years have therefore been based on geochemical models of carbon and sulphur cycling. However, these reconstructions vary widely, particularly for the Mesozoic and early Cenozoic eras. Here we show that the abundance of charcoal in mire settings is controlled by pO2, and use this proxy to reconstruct the concentration of atmospheric oxygen for the past 400million years. We estimate that pO2 was continuously above 26% during the Carboniferous and Permian periods, and that it declined abruptly around the time of the Permian-Triassic mass extinction. During the Triassic and Jurassic periods, pO2 fluctuated cyclically, with amplitudes up to 10% and a frequency of 20-30million years. Atmospheric oxygen concentrations have declined steadily from the middle of the Cretaceous period to present-day values of about 21%. We conclude, however, that variation in pO2 was not the main driver of the loss of faunal diversity during the Permo-Triassic and Triassic-Jurassic mass extinction events.

  7. Homemade bone charcoal adsorbent for defluoridation of groundwater in Thailand.

    PubMed

    Smittakorn, Sunisa; Jirawongboonrod, Nithat; Mongkolnchai-arunya, Surat; Durnford, Deanna

    2010-12-01

    High levels of fluoride in groundwater are a significant environmental and health problem in Thailand, as in many parts of the world. Small household defluoridators have several advantages over centralized treatment systems. In Thailand, however, use of bone char for water treatment has met resistance because of objectionable taste and odours of the water produced and the social resistance to handling fresh bone. This paper presents a method that uses bone charcoal as an absorbent for removing fluoride from groundwater. The commercially provided boiled bone is burned in a simple homemade furnace that can be constructed, operated and maintained easily by small rural householders. The method to produce the Thai bone char eliminates the odour and objectionable taste and also does not require the user to handle fresh bone, thus eliminating the social resistance. To evaluate the efficacy of the absorbent, batch experiments compare Thai and Indian bone char. Sorption isotherms are fit to the Freundlich and Langmuir equations and the kinetics are modelled using the pseudo first-order Lagergren equation. Results show that the sorption characteristics of Thai bone char compare favourably with the Indian bone char, with approximately 80% of the fluoride removed in both cases. PMID:20705992

  8. Sampling frequency affects the processing of Actigraph raw acceleration data to activity counts.

    PubMed

    Brønd, Jan Christian; Arvidsson, Daniel

    2016-02-01

    ActiGraph acceleration data are processed through several steps (including band-pass filtering to attenuate unwanted signal frequencies) to generate the activity counts commonly used in physical activity research. We performed three experiments to investigate the effect of sampling frequency on the generation of activity counts. Ideal acceleration signals were produced in the MATLAB software. Thereafter, ActiGraph GT3X+ monitors were spun in a mechanical setup. Finally, 20 subjects performed walking and running wearing GT3X+ monitors. Acceleration data from all experiments were collected with different sampling frequencies, and activity counts were generated with the ActiLife software. With the default 30-Hz (or 60-Hz, 90-Hz) sampling frequency, the generation of activity counts was performed as intended with 50% attenuation of acceleration signals with a frequency of 2.5 Hz by the signal frequency band-pass filter. Frequencies above 5 Hz were eliminated totally. However, with other sampling frequencies, acceleration signals above 5 Hz escaped the band-pass filter to a varied degree and contributed to additional activity counts. Similar results were found for the spinning of the GT3X+ monitors, although the amount of activity counts generated was less, indicating that raw data stored in the GT3X+ monitor is processed. Between 600 and 1,600 more counts per minute were generated with the sampling frequencies 40 and 100 Hz compared with 30 Hz during running. Sampling frequency affects the processing of ActiGraph acceleration data to activity counts. Researchers need to be aware of this error when selecting sampling frequencies other than the default 30 Hz. PMID:26635347

  9. Reinforcing Sampling Distributions through a Randomization-Based Activity for Introducing ANOVA

    ERIC Educational Resources Information Center

    Taylor, Laura; Doehler, Kirsten

    2015-01-01

    This paper examines the use of a randomization-based activity to introduce the ANOVA F-test to students. The two main goals of this activity are to successfully teach students to comprehend ANOVA F-tests and to increase student comprehension of sampling distributions. Four sections of students in an advanced introductory statistics course…

  10. Effect of sample handling on thiamine and thiaminolytic activity in alewife

    USGS Publications Warehouse

    Wright, G.M.; Brown, S.B.; Brown, L.R.; Moore, K.; Villella, M.; Zajicek, J.L.; Tillitt, D.E.; Fitzsimons, J.D.; Honeyfield, D.C.

    2005-01-01

    Alewives Alosa pseudoharengus were collected to evaluate handling and processing conditions that may affect the measurement of their thiamine-thiaminase content. Fish were captured by otter trawl, and reference samples of live fish were quick-frozen on dry ice immediately following capture. Other samples were placed on wet ice (4??C) or held in ambient lake water (21.5??C) for periods of up to 5 h before freezing. Total thiamine levels for reference samples averaged 26 nmol/g and consisted of 66, 15, and 19% thiamine pyrophosphate (TPP), thiamine monophosphate (TMP), and unphosphorylated thiamine (Th), respectively. After 120 min at either 4??C or 21.5??C, total thiamine concentrations were lower. At 21.5??C, the TPP proportion had decreased by 30 min and the proportion as Th increased after 60 min. In the groups sampled after 5 h, total thiamine concentrations were not altered but the proportion of TPP was lower and that of Th was higher than in reference samples. The stability of thiamine in thawed muscle samples from previously frozen alewives was poor (40% loss by 1 h at 22??C and 30% loss by 2 h at 4??C). Thiaminase activity averaged 5,975 pmol??g wet weight -1??min-1 in reference samples. In fresh-caught alewives, thiaminase activities were remarkably consistent throughout the sampling period. At 4??C, thiaminase activity in muscle tissue from previously frozen alewives was stable for the entire investigation period. At 25??C, the activity initially increased by 40% after 60 min but then decreased to 50% of initial value after 5 h. We conclude that sampling times greater than 25 min could cause some changes in the various thiamine forms and net loss in total thiamine. The thiamine content in previously frozen alewife samples is highly labile, requiring low temperatures during processing for analysis. ?? Copyright by the American Fisheries Society 2005.

  11. Study of proton and neutron activation of metal samples in low Earth orbit

    NASA Technical Reports Server (NTRS)

    Laird, C. E.

    1984-01-01

    Progress in the following activities has been made: the analysis of the gamma ray spectra taken from samples flown in Spacelab 2; the search for and review of neutron and proton activation cross sections needed to analyze the results of the Long Duration Exposure Facility (LDEF) activation measurements; the consideration given to data analysis of the LDEF and Spacelab 2 samples; the plan to measure relevant cross sections with nuclear accelerator measurements; and the preparation of an extended gamma ray calibration sources continues through planning and direct measurement of gamma ray efficiency for a Ge(Li) as a function of position along the surface of the detector housing.

  12. Active Search on Carcasses versus Pitfall Traps: a Comparison of Sampling Methods.

    PubMed

    Zanetti, N I; Camina, R; Visciarelli, E C; Centeno, N D

    2016-04-01

    The study of insect succession in cadavers and the classification of arthropods have mostly been done by placing a carcass in a cage, protected from vertebrate scavengers, which is then visited periodically. An alternative is to use specific traps. Few studies on carrion ecology and forensic entomology involving the carcasses of large vertebrates have employed pitfall traps. The aims of this study were to compare both sampling methods (active search on a carcass and pitfall trapping) for each coleopteran family, and to establish whether there is a discrepancy (underestimation and/or overestimation) in the presence of each family by either method. A great discrepancy was found for almost all families with some of them being more abundant in samples obtained through active search on carcasses and others in samples from traps, whereas two families did not show any bias towards a given sampling method. The fact that families may be underestimated or overestimated by the type of sampling technique highlights the importance of combining both methods, active search on carcasses and pitfall traps, in order to obtain more complete information on decomposition, carrion habitat and cadaveric families or species. Furthermore, a hypothesis advanced on the reasons for the underestimation by either sampling method showing biases towards certain families. Information about the sampling techniques indicating which would be more appropriate to detect or find a particular family is provided. PMID:26732526

  13. Resistance mechanisms to toxin-mediated charcoal rot infection in maturity group III soybean: role of seed phenol lignin soflavones sugars and seed minerals in charcoal rot resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Charcoal rot is a disease caused by the fungus Macrophomina phaseolina (Tassi) Goid, and thought to infect the plants through roots by a toxin-mediated mechanism, resulting in yield loss and poor seed quality, especially under drought conditions. The mechanism by which this infection occurs is not y...

  14. Artifact free denuder method for sampling of carbonaceous aerosols

    NASA Astrophysics Data System (ADS)

    Mikuška, P.; Vecera, Z.; Broškovicová, A.

    2003-04-01

    Over the past decade, a growing attention has been focused on the carbonaceous aerosols. Although they may account for 30--60% of the total fine aerosol mass, their concentration and formation mechanisms are not well understood, particularly in comparison with major fine particle inorganic species. The deficiency in knowledge of carbonaceous aerosols results from their complexity and because of problems associated with their collection. Conventional sampling techniques of the carbonaceous aerosols, which utilize filters/backup adsorbents suffer from sampling artefacts. Positive artifacts are mainly due to adsorption of gas-phase organic compounds by the filter material or by the already collected particles, whereas negative artifacts arise from the volatilisation of already collected organic compounds from the filter. Furthermore, in the course of the sampling, the composition of the collected organic compounds may be modified by oxidants (O_3, NO_2, PAN, peroxides) that are present in the air passing through the sampler. It is clear that new, artifact free, method for sampling of carbonaceous aerosols is needed. A combination of a diffusion denuder and a filter in series is very promising in this respect. The denuder is expected to collect gaseous oxidants and gas-phase organic compounds from sample air stream prior to collection of aerosol particles on filters, and eliminate thus both positive and negative sampling artifacts for carbonaceous aerosols. This combination is subject of the presentation. Several designs of diffusion denuders (cylindrical, annular, parallel plate, multi-channel) in combination with various types of wall coatings (dry, liquid) were examined. Special attention was given to preservation of the long-term collection efficiency. Different adsorbents (activated charcoal, molecular sieve, porous polymers) and sorbents coated with various chemical reagents (KI, Na_2SO_3, MnO_2, ascorbic acid) or chromatographic stationary phases (silicon oils

  15. Charcoal Morphology, a Useful Indicator of Fire Signature in Prosser Lake, British Columbia, Canada.

    NASA Astrophysics Data System (ADS)

    Enache, M. D.; Cumming, B. F.

    2004-12-01

    Observations of charcoal particle size and morphology were used along with quantitative analysis to extract indications on fire events over the last century from Prosser Lake (49\\deg45.05 N, 120\\deg37.30 W), a mesotrophic and slightly meromictic lake from British Columbia, Canada. Charcoal particles >150μ m were visually identified at a 0.5-3 years resolution in a laminated sedimentary sequence. According to their shape and structural features, charcoal particles were classified in seven morphologically distinct types and their abundances were assessed using Image Analysis techniques. Distributions of charcoal types were assessed as a proxy to fire events recorded between 1919-2000 and subsequent mechanisms of transportation-sedimentation to lake sediments. Frequent fires taking place before 1944, produced high amounts of charred particles, but strong fires that took place in 1939, 1940, 1958 and 1960 were poorly recorded by most of the charcoal types, whereas post-1944 periods of high precipitation levels without fire events increased their abundance. However, fragile-type fragments displaying high porosity walls showed a strong and significant correlation (R2 = 0.7; p = 0.02) with historically recorded forest fire in the proximity of Prosser Lake. Those fragments, according to their shape and structure might originate from high fragmentation of wood burning at high temperatures or by burning of small branches and leaves. Being very fragile, particles of this type would be destroyed by eventual secondary transportation processes and would not occur in levels not related to fire events. The remaining types of charcoal from Prosser Lake sediments displayed distributions biased by secondary transportation-sedimentation processes. We propose that charcoal morphology can be a useful indicator of fire occurrence, proximity of source-area and transportation-sedimentation mechanisms.

  16. Detection and evaluation of endocrine-disruption activity in water samples from Portuguese rivers.

    PubMed

    Quirós, Laia; Céspedes, Raquel; Lacorte, Sílvia; Viana, Paula; Raldúa, Demetrio; Barceló, Damià; Piña, Benjamin

    2005-02-01

    Water samples (n = 183) from Portuguese rivers were tested for the presence of endocrine disruptors using the recombinant yeast assay (RYA) combined with chemical identification of compounds having endocrine-disruption properties by liquid chromatography coupled to mass spectrometry. Ten selected locations were sampled monthly for a period of 20 months, from April 2001 to December 2002. More than 90% of samples showed either no detectable or low levels of estrogenicity (<0.1 ng/L of estradiol equivalents). The remaining samples (17 in total, 9.3%) showed estrogenicity values ranging from 0.1 to 1.7 ng/L of estradiol equivalents; only two samples showed values greater than 1 ng/L of estradiol equivalents. Most highly estrogenic samples (13 of 17 samples) originated in five sampling sites clustered in two zones near Porto and Lisbon. Chemical analysis detected alkylphenolic compounds (octyl- and nonylphenol plus nonylphenol ethoxylates) in all samples, albeit at concentrations less than 1 microg/L for each compound in 80% of samples. Total analyte concentration exceeded 10 microg/L in only 10 samples, with all but one of those originating from only two sampling sites. In these two locations, a good correlation was observed between the concentrations of octylphenol, nonylphenol, and to a lesser extent, bisphenol A in the samples and their estrogenicity values as calculated by RYA. We conclude that estrogenic activity can be explained by alkylphenol contamination in only these sites; for the remainder, we propose that pesticides and urban waste may be the main factors responsible for estrogenic contamination. PMID:15719999

  17. Qualitative Elemental Analyses of a Meteorite Sample Found in Turkey by Photo-activation Analysis Method

    NASA Astrophysics Data System (ADS)

    Ertugay, C.; Boztosun, I.; Ozmen, S. F.; Dapo, H.

    2015-04-01

    In this paper, a meteorite sample provided from TÜBITAK National Observatory found in Turkey has been investigated by using a clinical linear accelerator that has endpoint energy of 18 MeV, and a high purity Germanium detector for qualitative elemental analysis within photo-activation analysis method. 21 nuclei ranging from 24Na to 149Nd have been identified in the meteorite sample.

  18. Thermal activation of catalytic microjets in blood samples using microfluidic chips†

    PubMed Central

    Soler, Lluís; Martínez-Cisneros, Cynthia; Swiersy, Anka; Sánchez, Samuel; Schmidt, Oliver G.

    2014-01-01

    We demonstrate that catalytic microjet engines can out-swim high complex media composed of red blood cells and serum. Despite the challenge presented by the high viscosity of the solution at room temperature, the catalytic microjets can be activated at physiological temperature and, consequently, self-propel in diluted solutions of blood samples. We prove that these microjets self-propel in 10× diluted blood samples using microfluidic chips. PMID:24089195

  19. Activation energy for a model ferrous-ferric half reaction from transition path sampling

    NASA Astrophysics Data System (ADS)

    Drechsel-Grau, Christof; Sprik, Michiel

    2012-01-01

    Activation parameters for the model oxidation half reaction of the classical aqueous ferrous ion are compared for different molecular simulation techniques. In particular, activation free energies are obtained from umbrella integration and Marcus theory based thermodynamic integration, which rely on the diabatic gap as the reaction coordinate. The latter method also assumes linear response, and both methods obtain the activation entropy and the activation energy from the temperature dependence of the activation free energy. In contrast, transition path sampling does not require knowledge of the reaction coordinate and directly yields the activation energy [C. Dellago and P. G. Bolhuis, Mol. Simul. 30, 795 (2004), 10.1080/08927020412331294869]. Benchmark activation energies from transition path sampling agree within statistical uncertainty with activation energies obtained from standard techniques requiring knowledge of the reaction coordinate. In addition, it is found that the activation energy for this model system is significantly smaller than the activation free energy for the Marcus model, approximately half the value, implying an equally large entropy contribution.

  20. Evaluation of bacteria isolated from rice rhizosphere for biological control of charcoal rot of sorghum caused by Macrophomina phaseolina (Tassi) Goid.

    PubMed

    Gopalakrishnan, Subramaniam; Humayun, Pagidi; Kiran, Bandru Keerthi; Kannan, Iyer Girish Kumar; Vidya, Meesala Sree; Deepthi, Kanala; Rupela, Om

    2011-06-01

    A total of 360 bacteria, isolated from the rhizospheres of a system of rice intensification (SRI) fields, were characterized for the production of siderophore, fluorescence, indole acetic acid (IAA), hydrocyanic acid (HCN) and solubilization of phosphorus. Of them, seven most promising isolates (SRI-156, -158, -178, -211, -229, -305 and -360) were screened for their antagonistic potential against Macrophomina phaseolina (causes charcoal rot in sorghum) by dual culture assay, blotter paper assay and in greenhouse. All the seven isolates inhibited M. phaseolina in dual culture assay, whereas six isolates solubilized phosphorous (except SRI-360), all seven produced siderophore, four produced fluorescence (except SRI-178, -229 and -305), six produced IAA (except SRI-305) and five produced HCN (except SRI-158 and -305). In the blotter paper assay, no charcoal rot infection was observed in SRI-156-treated sorghum roots, indicating complete inhibition of the pathogen, while the roots treated with the other isolates showed 49-76% lesser charcoal rot infection compared to the control. In the antifungal activity test (in green house on sorghum), all the isolates increased shoot dry mass by 15-23% and root dry mass by 15-20% (except SRI-158 and -360), over the control. In order to confirm the plant growth-promoting (PGP) traits of the isolates, the green house experiment was repeated but, in the absence of M. phaseolina. The results further confirmed the PGP traits of the isolates as evidenced by increases in shoot and root dry mass, 22-100% and 5-20%, respectively, over the control. The sequences of 16S rDNA gene of the isolates SRI-156, -158, -178, -211, -229, -305 and -360 were matched with Pseudomonas plecoglossicida, Brevibacterium antiquum, Bacillus altitudinis, Enterobacter ludwigii, E. ludwigii, Acinetobacter tandoii and P. monteilii, respectively in BLAST analysis. This study indicates that the selected bacterial isolates have the potential for PGP and control of

  1. Activity and growth of microbial populations in pressurized deep-sea sediment and animal gut samples.

    PubMed

    Tabor, P S; Deming, J W; Ohwada, K; Colwell, R R

    1982-08-01

    Benthic animals and sediment samples were collected at deep-sea stations in the northwest (3,600-m depth) and southeast (4,300- and 5200-m depths) Atlantic Ocean. Utilization rates of [14C]glutamate (0.67 to 0.74 nmol) in sediment suspensions incubated at in situ temperatures and pressures (3 to 5 degrees C and 360, 430, or 520 atmospheres) were relatively slow, ranging from 0.09 to 0.39 nmol g-1 day-1, whereas rates for pressurized samples of gut suspensions varied widely, ranging from no detectable activity to a rapid rate of 986 nmol g-1 day-1. Gut flora from a holothurian specimen and a fish demonstrated rapid, barophilic substrate utilization, based on relative rates calculated for pressurized samples and samples held at 1 atm (101.325 kPa). Substrate utilization by microbial populations in several sediment samples was not inhibited by in situ pressure. Deep-sea pressures did not restrict growth, measured as doubling time, of culturable bacteria present in a northwest Atlantic sediment sample and in a gut suspension prepared from an abyssal scavenging amphipod. From the results of this study, it was concluded that microbial populations in benthic environments can demonstrate significant metabolic activity under deep-ocean conditions of temperature and pressure. Furthermore, rates of microbial activity in the guts of benthic macrofauna are potentially more rapid than in surrounding deep-sea sediments. PMID:6127054

  2. Activity and growth of microbial populations in pressurized deep-sea sediment and animal gut samples.

    PubMed Central

    Tabor, P S; Deming, J W; Ohwada, K; Colwell, R R

    1982-01-01

    Benthic animals and sediment samples were collected at deep-sea stations in the northwest (3,600-m depth) and southeast (4,300- and 5200-m depths) Atlantic Ocean. Utilization rates of [14C]glutamate (0.67 to 0.74 nmol) in sediment suspensions incubated at in situ temperatures and pressures (3 to 5 degrees C and 360, 430, or 520 atmospheres) were relatively slow, ranging from 0.09 to 0.39 nmol g-1 day-1, whereas rates for pressurized samples of gut suspensions varied widely, ranging from no detectable activity to a rapid rate of 986 nmol g-1 day-1. Gut flora from a holothurian specimen and a fish demonstrated rapid, barophilic substrate utilization, based on relative rates calculated for pressurized samples and samples held at 1 atm (101.325 kPa). Substrate utilization by microbial populations in several sediment samples was not inhibited by in situ pressure. Deep-sea pressures did not restrict growth, measured as doubling time, of culturable bacteria present in a northwest Atlantic sediment sample and in a gut suspension prepared from an abyssal scavenging amphipod. From the results of this study, it was concluded that microbial populations in benthic environments can demonstrate significant metabolic activity under deep-ocean conditions of temperature and pressure. Furthermore, rates of microbial activity in the guts of benthic macrofauna are potentially more rapid than in surrounding deep-sea sediments. PMID:6127054

  3. Research on dye wastewater decoloration by pulse discharge plasma combined with charcoal derived from spent tea leaves.

    PubMed

    Wang, Tiecheng; Qu, Guangzhou; Pei, Shuzhao; Liang, Dongli; Hu, Shibin

    2016-07-01

    Pulsed discharge plasma (PDP) combined with charcoal (PDP-charcoal) was employed to treat dye wastewater, with methyl orange (MO) as the model pollutant. The charcoal was prepared using spent tea leaves and was characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, and Boehm titration to investigate the adsorption and catalytic characteristics before and after adsorption and PDP treatment. The prepared charcoal exhibited a high MO adsorption capacity, and the adsorption process followed the pseudo-second-order kinetic model and the Freundlich model. The MO decoloration efficiency reached 69.8 % within 7.5 min of treatment in the PDP-charcoal system, whereas values of 29.2 and 25.9 % were achieved in individual PDP and charcoal systems, respectively. The addition of n-butanol and H2PO4 (-) presented inhibitive effects on MO decoloration in the PDP system. However, these effects were much weaker in the PDP-charcoal system. In addition, the effects of charcoal on O3 and H2O2 formation were evaluated, and the results showed that both the O3 and H2O2 concentrations decreased in the presence of charcoal. The MO decomposition intermediates were analyzed using UV-Vis spectrometry and GC-MS. 1,4-Benzoquinone, 4-nitrophenol, 4-hydroxyaniline, and N,N'-dimethylaniline were detected. A possible pathway for MO decomposition in this system was proposed. PMID:27026548

  4. A Rapid Method for Assaying Thiaminase I Activity in Diverse Biological Samples

    PubMed Central

    Kraft, Clifford E.; Gordon, Eric R. L.; Angert, Esther R.

    2014-01-01

    Vitamin B1 (thiamine) deficiencies can lead to neurological disorders, reproductive failure and death in wild and domestic animal populations. In some cases, disease is brought about by the consumption of foods high in thiaminase I activity. Levels of thiaminase activity in these foods are highly variable and the factors leading to production of this enzyme are poorly understood. Here we describe improvements in a spectrophotometric thiaminase I activity assay that measures the disappearance of 4-nitrothiophenol, a favored nucleophile co-substrate that replaces the thiazole portion of thiamine during the inactivation of thiamine by the enzyme. Scalable sample processing protocols and a 96-well microtiter plate format are presented that allow the rapid evaluation of multiple, replicated samples in the course of only a few hours. Observed levels of activity in bacterial culture supernatant, fish, ferns and molluscs using this colorimetric assay were similar to previously published reports that employed a radiometric method. Organisms devoid of thiaminase I, based upon previous work, showed no activity with this assay. In addition, activity was found in a variety of fishes and one fern species from which this enzyme had not previously been reported. Overall, we demonstrate the suitability of this technique for measuring thiaminase I activity within small amounts of tissue and environmental samples with replication levels that were heretofore prohibitive. The assay provides a considerable improvement in the ability to examine and understand the properties of an enzyme that has a substantial influence on organism and ecosystem health. PMID:24675843

  5. Preliminary results of systematic sampling of gas manifestations in geodynamically active areas of Greece

    NASA Astrophysics Data System (ADS)

    Daskalopoulou, Kyriaki; D'Alessandro, Walter; Calabrese, Sergio; Kyriakopoulos, Konstantinos

    2016-04-01

    Greece is located on a convergent plate boundary comprising the subduction of the African Plate beneath the Eurasian, while the Arabian plate approaches the Eurasian in a northwestward motion. It is considered to be one of the most tectonically active regions of Earth with a complex geodynamic setting, deriving from a long and complicated geological history. Due to this specific geological background, conditions for the formation of many thermal springs are favoured. In the past years, almost all the already known sites of degassing (fumaroles, soil gases, mofettes, gas bubbling in cold and thermal waters) located in the Hellenic area were sampled at least one time. Collected samples were analysed for their chemical (He, Ne, Ar, O2, N2, H2, H2S, CO, CH4 and CO2) and isotopic composition (He, C and N). Some of these sites have been selected for systematic sampling. Four of them have records longer than 10 years with tens of samplings also considering some literature data. Two of the sites are located in active volcanic areas (Santorini and Nisyros) while the other two are close to actively spreading graben structures with intense seismic activity (Gulf of Korinth and Sperchios basin). Results allowed to define long term background values and also some interesting variation related to seismic or volcanic activity.

  6. Determination of Long-Lived Neutron Activation Products in Reactor Shielding Concrete Samples

    SciTech Connect

    Zagar, Tomaz; Ravnik, Matjaz

    2002-10-15

    The results of activation studies of TRIGA research reactor concrete shielding are given. Samples made of ordinary and barytes concrete were irradiated in the reactor to simulate neutron activation in the shielding concrete. Long-lived neutron-induced gamma-ray-emitting radioactive nuclides were measured in the samples with a high-purity germanium detector. The most active long-lived radioactive nuclides in the ordinary concrete samples were found to be {sup 60}Co and {sup 152}Eu. In the barytes concrete samples, the most active long-lived radioactive nuclides were {sup 60}Co, {sup 133}Ba, and {sup 152}Eu. Activation in the concrete was also calculated using the ORIGEN2 code and compared to experimental results. Simple radioactive nuclide generation and depletion calculation using one-group cross-section libraries provided together with the ORIGEN2 code did not give conservative results. Significant discrepancies were observed for some nuclides. For accurate long-lived radioactive nuclide generation in reactor shielding, material-specific cross-section libraries should be generated and verified by measurement.

  7. Chemical recalcitrance of biochar and wildfire charcoal: how similar are they?

    NASA Astrophysics Data System (ADS)

    Santin, Cristina; Doerr, Stefan H.; Merino, Agustin

    2016-04-01

    The enhanced chemical resistance to biological degradation of pyrogenic materials, either produced during wildfires (charcoal) or by man (biochar), makes them long-term carbon sinks once incorporated in soils. In spite of their fundamental similarities, studies comparing the chemical recalcitrance of biochar and wildfire charcoal are scarce because analogous materials for accurate comparison are not easily available. Using solid-state 13C cross polarization-magic angle spinning nuclear magnetic resonance spectroscopy we characterized the chemical recalcitrance of pyrogenic materials generated from the same unburnt feedstooks (litter and dead wood from Pinus banksiana): (a) charcoal from a high-intensity wildfire and (b) biochar obtained by slow pyrolysis [3 treatments: 2 h at 350, 500 and 650°C]. For quantification, the spectra were divided into four regions representing different chemical environments of the 13C nucleus: alkyl C (0-45 ppm), O-alkyl C (45-110 ppm), olefinic and aromatic C(110-160 ppm), and carbonyl C (160-210 ppm). As an indicator of chemical recalcitrance, the degree of aromaticity (%) was calculated as follow: aromatic-C ∗ 100 / (alkyl C+ O alkyl-C + aromatic-C). The pyrogenic materials derived from wood show higher degrees of aromaticity (68 to 88%) than pyrogenic material derived from litter (40 to 88%). When comparing biochar and wildfire charcoal, biochars produced at 500 and 650°C always have higher degrees of aromaticity than wildfire charcoals, irrespective of the original feedstock. Wildfire charcoals always show a more heterogeneous chemical composition, with alkyl and O-alkyl compounds present even in charcoal generated at very high temperatures (temperatures up to 950 °C were recorded on the litter surface during the wildfire). However, biochars produced at 500 and 650 °C are mostly aromatic, and only the biochars produced at 350 °C show partial contribution of alkyl-C compounds. Our results suggest that biochar-type pyrogenic

  8. Neural Encoding of Odors during Active Sampling and in Turbulent Plumes.

    PubMed

    Huston, Stephen J; Stopfer, Mark; Cassenaer, Stijn; Aldworth, Zane N; Laurent, Gilles

    2015-10-21

    Sensory inputs are often fluctuating and intermittent, yet animals reliably utilize them to direct behavior. Here we ask how natural stimulus fluctuations influence the dynamic neural encoding of odors. Using the locust olfactory system, we isolated two main causes of odor intermittency: chaotic odor plumes and active sampling behaviors. Despite their irregularity, chaotic odor plumes still drove dynamic neural response features including the synchronization, temporal patterning, and short-term plasticity of spiking in projection neurons, enabling classifier-based stimulus identification and activating downstream decoders (Kenyon cells). Locusts can also impose odor intermittency through active sampling movements with their unrestrained antennae. Odors triggered immediate, spatially targeted antennal scanning that, paradoxically, weakened individual neural responses. However, these frequent but weaker responses were highly informative about stimulus location. Thus, not only are odor-elicited dynamic neural responses compatible with natural stimulus fluctuations and important for stimulus identification, but locusts actively increase intermittency, possibly to improve stimulus localization. PMID:26456047

  9. Monitoring airborne fungal spores in an experimental indoor environment to evaluate sampling methods and the effects of human activity on air sampling.

    PubMed Central

    Buttner, M P; Stetzenbach, L D

    1993-01-01

    Aerobiological monitoring was conducted in an experimental room to aid in the development of standardized sampling protocols for airborne microorganisms in the indoor environment. The objectives of this research were to evaluate the relative efficiencies of selected sampling methods for the retrieval of airborne fungal spores and to determine the effect of human activity on air sampling. Dry aerosols containing known concentrations of Penicillium chrysogenum spores were generated, and air samples were taken by using Andersen six-stage, Surface Air System, Burkard, and depositional samplers. The Andersen and Burkard samplers retrieved the highest numbers of spores compared with the measurement standard, an aerodynamic particle sizer located inside the room. Data from paired samplers demonstrated that the Andersen sampler had the highest levels of sensitivity and repeatability. With a carpet as the source of P. chrysogenum spores, the effects of human activity (walking or vacuuming near the sampling site) on air sampling were also examined. Air samples were taken under undisturbed conditions and after human activity in the room. Human activity resulted in retrieval of significantly higher concentrations of airborne spores. Surface sampling of the carpet revealed moderate to heavy contamination despite relatively low airborne counts. Therefore, in certain situations, air sampling without concomitant surface sampling may not adequately reflect the level of microbial contamination in indoor environments. PMID:8439150

  10. Modification of phencyclidine intoxification and biodisposition by charcoal and other treatments.

    PubMed

    Lyddane, J E; Thomas, B F; Compton, D R; Martin, B R

    1988-06-01

    Studies were conducted to determine whether single or combination treatments of charcoal, paraffin, cholestyramine, and/or ammonium chloride (NH4Cl), would alter the rotarod-measured motor dysfunction induced by 10 to 90 mg/kg of phencyclidine (PCP). Additionally, the effect of NH4Cl/charcoal treatment of the biodisposition of 50 mg/kg PCP was evaluated in order to assess whether amelioration of behavioral effects could be correlated to alterations in brain levels, plasma levels, and/or the renal clearance of PCP and metabolites. NH4Cl/charcoal treatment proved more effective at reducing intoxication than either treatment singly, though effectiveness was reduced by larger doses of PCP. NH4Cl/charcoal treatment reduced intoxification by 40, 16, and 21% at PCP doses of 10, 25, and 50 mg/kg. However, the reduction in motor dysfunction observed at 25 and 50 mg/kg PCP was greater than the sum of the individual treatments. In contrast, the effect of combined NH4Cl and charcoal treatment on the biodisposition of 50 mg/kg PCP is not synergistic, but appears instead to be due simply to the additive effects of the individual treatments. Thus the amelioration of PCP intoxication cannot be fully explained by alterations in PCP biodisposition. PMID:3174769

  11. Analysis of active neutron multiplicity data for Y-12 skull oxide samples

    SciTech Connect

    Krick, M.S.; Ensslin, N.; Ceo, R.N.; May, P.K.

    1996-09-01

    Previous work on active neutron multiplicity measurements and analyses is summarized. New active multiplicity measurements are described for samples of Y-12 skull oxide using an Active Well Coincidence Counter and MSR4 multiplicity electronics. Neutron multiplication values for the samples were determined from triples/doubles ratios. Neutron multiplication values were also obtained from Monte Carlo calculations using the MCNP code and the results compared with the experimental values. A calibration curve of AmLi source-sample coupling vs neutron multiplication was determined and used for active multiplicity assay of the skull oxides. The results are compared with those obtained from assay with the conventional calibration-curve technique, where the doubles rate is calibrated vs the {sup 235}U mass. The coupling-multiplication relationship determined for the skull oxides is compared with that determined earlier for pure high-enrichment uranium metal and pure uranium oxide. Conclusions are drawn about the application of active multiplicity techniques to uranium assay. Additional active multiplicity measurements and calculations are recommended.

  12. Faulting processes in active faults - Evidences from TCDP and SAFOD drill core samples

    SciTech Connect

    Janssen, C.; Wirth, R.; Wenk, H. -R.; Morales, L.; Naumann, R.; Kienast, M.; Song, S. -R.; Dresen, G.

    2014-08-20

    The microstructures, mineralogy and chemistry of representative samples collected from the cores of the San Andreas Fault drill hole (SAFOD) and the Taiwan Chelungpu-Fault Drilling project (TCDP) have been studied using optical microscopy, TEM, SEM, XRD and XRF analyses. SAFOD samples provide a transect across undeformed host rock, the fault damage zone and currently active deforming zones of the San Andreas Fault. TCDP samples are retrieved from the principal slip zone (PSZ) and from the surrounding damage zone of the Chelungpu Fault. Substantial differences exist in the clay mineralogy of SAFOD and TCDP fault gouge samples. Amorphous material has been observed in SAFOD as well as TCDP samples. In line with previous publications, we propose that melt, observed in TCDP black gouge samples, was produced by seismic slip (melt origin) whereas amorphous material in SAFOD samples was formed by comminution of grains (crush origin) rather than by melting. Dauphiné twins in quartz grains of SAFOD and TCDP samples may indicate high seismic stress. The differences in the crystallographic preferred orientation of calcite between SAFOD and TCDP samples are significant. Microstructures resulting from dissolution–precipitation processes were observed in both faults but are more frequently found in SAFOD samples than in TCDP fault rocks. As already described for many other fault zones clay-gouge fabrics are quite weak in SAFOD and TCDP samples. Clay-clast aggregates (CCAs), proposed to indicate frictional heating and thermal pressurization, occur in material taken from the PSZ of the Chelungpu Fault, as well as within and outside of the SAFOD deforming zones, indicating that these microstructures were formed over a wide range of slip rates.

  13. Development and calibration of a portable radon sampling system for groundwater 222Rn activity concentration measurements.

    PubMed

    Lucas, Fabio de Oliveira; de Oliveira, Igor José Chaves; Ribeiro, Fernando Brenha

    2009-10-01

    The assembling of a system for field sampling and activity concentration measurement of radon dissolved in groundwater is described. Special attention is given in presenting the calibration procedure to obtain the radon activity concentration in groundwater from the raw counting rate registered in a portable scintillation detector and in establishing the precision of the activity concentration measurements. A field procedure was established and the system tested during one year of monthly observations of (222)Rn activity concentration in groundwater drawn from two wells drilled on metamorphic rocks exposed at Eastern São Paulo State, Brazil. The observed mean (222)Rn activity concentrations are 374Bq/dm(3) in one well and about 1275Bq/dm(3) in the other one. In both wells the (222)Rn activity concentrations showed a seasonal variation similar to variations previously reported in the literature for the same region. PMID:19608307

  14. Development of an automatic volcanic ash sampling apparatus for active volcanoes

    NASA Astrophysics Data System (ADS)

    Shimano, Taketo; Nishimura, Takeshi; Chiga, Nobuyuki; Shibasaki, Yoshinobu; Iguchi, Masato; Miki, Daisuke; Yokoo, Akihiko

    2013-12-01

    We develop an automatic system for the sampling of ash fall particles, to be used for continuous monitoring of magma ascent and eruptive dynamics at active volcanoes. The system consists of a sampling apparatus and cameras to monitor surface phenomena during eruptions. The Sampling Apparatus for Time Series Unmanned Monitoring of Ash (SATSUMA-I and SATSUMA-II) is less than 10 kg in weight and works automatically for more than a month with a 10-kg lead battery to obtain a total of 30 to 36 samples in one cycle of operation. The time range covered in one cycle varies from less than an hour to several months, depending on the aims of observation, allowing researchers to target minute-scale fluctuations in a single eruptive event, as well as daily to weekly trends in persistent volcanic activity. The latest version, SATSUMA-II, also enables control of sampling parameters remotely by e-mail commands. Durability of the apparatus is high: our prototypes worked for several months, in rainy and typhoon seasons, at windy and humid locations, and under strong sunlight. We have been successful in collecting ash samples emitted from Showa crater almost everyday for more than 4 years (2008-2012) at Sakurajima volcano in southwest Japan.

  15. Solid phase microextraction for active or passive sampling of methyl bromide during fumigations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The high diffusivity and volatility of methyl bromide make it an ideal compound for Solid Phase Micro Extraction (SPME)-based sampling of air prior to gas-chromatographic quantifications. SPME fibers can be used as active methyl bromide samplers, with high capacities and an equilibrium time of 1-2 m...

  16. DEVELOPMENT OF AN RH -DENUDED MIE ACTIVE SAMPLING SYSTEM AND TARGETED AEROSOL CALIBRATION

    EPA Science Inventory

    The MIE pDR 1200 nephelometer provides time resolved aerosol concentrations during personal and fixed-site sampling. Active (pumped) operation allows defining an upper PM2.5 particle size, however, this dramatically increases the aerosol mass passing through the phot...

  17. Stages of Change for Physical Activity in a Community Sample of Adolescents

    ERIC Educational Resources Information Center

    De Bourdeaudhuij, Ilse; Philippaerts, Renaat; Crombez, Geert; Matton, Lynn; Wijndaele, Katrien; Balduck, Anne-Line; Lefevre, Johan

    2005-01-01

    The aims of the present study were to investigate (1) the proportion of adolescents in each of the stages of change, (2) the differences in psychosocial factors and in physical activity between the stages, and (3) the classification accuracy using several reference criteria. A random sample of 38 schools from the Flemish community in Belgium…

  18. Estimating Activity Duration by Momentary Time-Sampling of Part or All of the Day

    ERIC Educational Resources Information Center

    Mansell, Jim; Beadle-Brown, Julie

    2011-01-01

    Background: Studies of engagement in meaningful activity often focus on a short period during the afternoon. The question arises whether this produces different results from studies covering the whole day. Methods: Data collected for 18 individuals using a 20-s momentary time-sample from 08:00 to 19:00 over a number of days for each person were…

  19. Associations between Physical Activity and Health-Related Factors in a National Sample of College Students

    ERIC Educational Resources Information Center

    Dinger, Mary K.; Brittain, Danielle R.; Hutchinson, Susan R.

    2014-01-01

    Objective: To examine associations between meeting the current moderate to vigorous physical activity (MVPA) recommendation and health-related factors in a national sample of college students. Participants: Participants (N = 67,861) completed the National College Health Assessment II during the Fall 2008/Spring 2009 academic year. Methods:…

  20. Comparative genetic activity of samples collected from two different urban waste incinerators

    SciTech Connect

    Vellosi, R.; Galli, A.; Rossi, F.; Morichetti, E.; Bronzetti, G.

    1988-09-01

    Incineration of industrial and urban waste materials is an important problem for the environmental contamination and therefore for human health. Environmental contaminants spread by urban incinerators can contain a complex mixture of toxic compounds such as dioxin, benzofurans, alogenate acids. It is important to evaluate the genetic damage induced by complex mixtures widespread in the environment. In the present work, the genotoxic activity of samples obtained from the urban incinerator of Florence was analyzed. The results were compared with those obtained with samples drawn from the urban Snamprogetti incinerator of Schio (Vicenza), where halogenated acids contained in the smoke are neutralized with the lime wash in a salification column. Samples were tested using prokaryotic (Salmonella typhimurium TA98, TA100 and TA102 strains) and eukaryotic (Saccharomyces cerevisiae, D7 strain) microorganisms. These systems permit one to obtain rapid, reproducible and reliable results in order to evaluate the genotoxic activity of substances present in the environment.

  1. Comparison of active and passive sampling strategies for the monitoring of pesticide contamination in streams

    NASA Astrophysics Data System (ADS)

    Assoumani, Azziz; Margoum, Christelle; Guillemain, Céline; Coquery, Marina

    2014-05-01

    constants (Rs). Each constant links the mass of the a target contaminant accumulated in the sampler to its concentration in water. At the end of the field application, the Rs are used to calculate the TWA concentration of each target contaminant with the final mass of the contaminants accumulated in the sampler. Stir Bar Sorptive Extraction (SBSE) is a solvent free sample preparation technique dedicated to the analysis of moderately hydrophobic to hydrophobic compounds in liquid and gas samples. It is composed of a magnet enclosed in a glass tube coated with a thick film of polydimethysiloxane (PDMS). We recently developed the in situ application of SBSE as a passive sampling technique (herein named "Passive SBSE") for the monitoring of agricultural pesticides. The aim of this study is to perform the calibration of the passive SBSE in the laboratory, and to apply and compare this technique to active sampling strategies for the monitoring of 16 relatively hydrophobic to hydrophobic pesticides in streams, during 2 1-month sampling campaigns. Time-weighted averaged concentrations of the target pesticides obtained from passive SBSE were compared to the target pesticide concentrations of grab samples, and time-related and flow-dependent samples of the streams. Results showed passive SBSE as an efficient alternative to conventional active sampling strategies.

  2. Instrumental neutron activation analysis data for cloud-water particulate samples, Mount Bamboo, Taiwan

    USGS Publications Warehouse

    Lin, Neng-Huei; Sheu, Guey-Rong; Wetherbee, Gregory A.; Debey, Timothy M.

    2013-01-01

    Cloud water was sampled on Mount Bamboo in northern Taiwan during March 22-24, 2002. Cloud-water samples were filtered using 0.45-micron filters to remove particulate material from the water samples. Filtered particulates were analyzed by instrumental neutron activation analysis (INAA) at the U.S. Geological Survey National Reactor Facility in Denver, Colorado, in February 2012. INAA elemental composition data for the particulate materials are presented. These data complement analyses of the aqueous portion of the cloud-water samples, which were performed earlier by the Department of Atmospheric Sciences, National Central University, Taiwan. The data are intended for evaluation of atmospheric transport processes and air-pollution sources in Southeast Asia.

  3. Highly stable rice-straw-derived charcoal in 3700-year-old ancient paddy soil: evidence for an effective pathway toward carbon sequestration.

    PubMed

    Wu, Mengxiong; Yang, Min; Han, Xingguo; Zhong, Ting; Zheng, Yunfei; Ding, Pin; Wu, Weixiang

    2016-01-01

    Recalcitrant charcoal application is predicted to decelerate global warming through creating a long-term carbon sink in soil. Although many studies have showed high stability of charcoal derived from woody materials, few have focused on the dynamics of straw-derived charcoal in natural environment on a long timescale to evaluate its potential for agricultural carbon sequestration. Here, we examined straw-derived charcoal in an ancient paddy soil dated from ~3700 calendar year before present (cal. year BP). Analytical results showed that soil organic matter consisted of more than 25% of charcoal in charcoal-rich layer. Similarities in morphology and molecular structure between the ancient and the fresh rice-straw-derived charcoal indicated that ancient charcoal was derived from rice straw. The lower carbon content, higher oxygen content, and obvious carbonyl of the ancient charcoal compared with fresh rice straw charcoal implied that oxidation occurred in the scale of thousands years. However, the dominant aromatic C of ancient charcoal indicated that rice-straw-derived charcoal was highly stable in the buried paddy soil due to its intrinsic chemical structures and the physical protection of ancient paddy wetland. Therefore, it may suggest that straw charcoal application is a potential pathway for C sequestration considering its longevity. PMID:25850742

  4. A means to make open-face charcoal detectors respond correctly to varying concentration radon fields

    SciTech Connect

    Distenfeld, C.H.

    1995-12-31

    Ronca-Battista and D. Gray 87, outlined the poor response of open-face charcoal detectors to varying concentration radon fields. At worst, for two day exposures with open-face charcoal canisters, their Table 4 indicated a 75% under-response for radon concentrations that were 10 times higher during the first day of two, 10:1. TCS has made similar measurements with open-faced and diffusion barrier detectors in 20:1, 1:20, and 1:1 fields. For the worst case 20:1, measurements indicate TCS two day open-face canisters under respond by 50%, while the Cohen and TCS diffusion barrier devices under responded by about 37%. The reasons for the under response are radon diffusion out of the charcoal due to the forces of lower concentration during the second half of the exposure, and uncompensated radioactive decay of radon gas.

  5. Emissions of air toxics from a simulated charcoal kiln. Final report, October 1997--September 1998

    SciTech Connect

    Lemieux, P.M.

    1999-06-01

    The report gives results of experiments in a laboratory-scale charcoal kiln simulator to evaluate emissions of hazardous air pollutants from the production of charcoal in Missouri-type kilns. Fixed combustion gases were measured using continuous monitors. In addition, other pollutants, including methanol, volatile organic compounds, semivolatile organic compounds, and particle emission rates and size distributions were measured using various techniques. Emissions of all pollutants are reported in units of grams emitted per unit mass of initial wood converted to charcoal. Two burn conditions--slow and fast--were examined. High levels of methanol, benzene, and fine particulate were emitted in all tests. The estimated emissions from the fast burn conditions were significantly higher than those from the slow burn conditions.

  6. Microscopic and mesoscopic structural features of an activated carbon sample, prepared from sorghum via activation by phosphoric acid

    SciTech Connect

    Temleitner, László; Pusztai, László; Rubio-Arroyo, Manuel F.; Aguilar-López, Sergio; Pizio, Orest

    2012-12-15

    Graphical abstract: Display Omitted Highlights: ► Preparation of a new activated carbon sample from sorghum. ► Characterization by adsorption/desorption methods. ► Determination of the structure by synchrotron X-ray diffraction. ► The sample is amorphous and contains distorted graphene fragments. ► A characteristic nanoscale distance is established from the radial distribution function. -- Abstract: An acidic chemical activation procedure has been used for preparing activated carbon with a surface area exceeding 1000 m{sup 2}/g from sorghum. In order to reveal structural features, synchrotron X-ray diffraction measurements have been performed. The structure of the material has been characterized by the total scattering structure factor and the radial distribution function describing short-range arrangement of atoms at distances of the order of a few atomic diameters as well as correlations at a longer scale, of the order of nanometers. The atomic arrangement has been found to be consistent with that of amorphous graphite-like carbon. As far as the mesoscopic structure is concerned, the presence of a characteristic distance is suggested on the basis of the clear nanometer scale oscillations of the radial distribution function, which distance may be assigned as the mesopore size in the material. It is suggested that the approach devized here may later be applied routinely for other activated carbon samples, too, for characterizing atomic and nanoscale order simultaneously.

  7. Carnivore activity in the Sima de los Huesos (Atapuerca, Spain) hominin sample

    NASA Astrophysics Data System (ADS)

    Sala, Nohemi; Arsuaga, Juan Luis; Martínez, Ignacio; Gracia-Téllez, Ana

    2014-08-01

    The Sima de los Huesos (SH) site is the largest accumulation of human remains from the Middle Pleistocene known to date. Studies in the last two decades have proposed different hypotheses to explain carnivore activity in the SH human sample. This study provides new data in order to test these different interpretations, and therefore to understand the role of the carnivores in site formation at SH. Carnivores are usually not the origin of large accumulations of hominin fossils in the Eurasian record. The results show that marks of carnivore activity in the SH sample appear very infrequently, which we interpret as indicating that carnivore activity was very sporadic at the site. This is in stark contrast with previous studies. The comparison of bone modification patterns at SH to actualistic carnivore data allows us to suggest that bears were likely to have been the carnivore responsible for the modification observed on both human and bear fossils.

  8. Soil stratigraphy of charcoal kiln remains (CKR) in the Litchfield Hills, CT, USA

    NASA Astrophysics Data System (ADS)

    Raab, Thomas; Hirsch, Florian; Ouimet, Will; Dethier, David

    2016-04-01

    Charcoal kiln relicts (CKRs) are small anthropogenic landforms that are often found in historic mining areas. CKRs have not been a big research topic yet but mainly were studied as by-products of archaeological excavations. In the last years newly available and very accurate Digital Elevation Models (DEMs) based on high-resolution Airborne Laser Scanning (ALS) data have been used to identify these archaeological remains. In addition, findings of several thousands CKRs in the North German Lowland have increased the awareness that historical charcoal production may significantly contribute to Late Holocene landscape change. Besides the archaeological aspect of CKRs, potential impacts of charcoal burning on the ecology of modern soil landscapes and ecosystem processes must be considered. A relatively high density of CKRs is found in the Litchfield Hills nearby the town of West Cornwall, Litchfield County, CT, USA. The CKRs are especially well preserved on slopes of the tributary valleys of the Housatonic River and form little, circular ramparts with diameters normally less than ten meters. First, rough field surveys in Litchfield County in spring 2015 have suggested differences between soils inside and outside the CKR. Soils on the CKR seem to have relatively deep humus-rich and charcoal containing topsoils whereas the topsoils outside the CKR appear typically thinner and less rich in humus. More thorough investigations have been started in autumn 2015 to prove the hypothesis that properties, distribution and development of soils are controlled by archaeological remains of historical charcoal burning. We present preliminary results from our field studies conducted in October 2015. The stratigraphy and the extent of the 26 CKRs were studied using a sedimentological-pedological approach by coring and trenching. Our results indicate that in Litchfield County the CKRs were used twice and in quick succession. Before the second reuse, the rim of the platform was stabilized

  9. An improved sup 222 Rn canister using a two-stage charcoal system

    SciTech Connect

    Scarpitta, S.C.; Harley, N.H. )

    1991-02-01

    A prototype for an improved passive {sup 222}Rn canister (R-Canister) was designed and compared to conventional charcoal canisters for its adsorptive and desorptive characteristics following exposures to {sup 222}Rn at 23{degrees}C in the presence of water vapor. The R-Canister, containing a two-stage charcoal system, minimizes the adverse effects of water vapor by maintaining the amount of adsorbed water vapor in the primary Rn adsorbent below the break-point of the charcoal. This is achieved by the placement of a desiccant charcoal cartridge 6 cm above the primary Rn adsorbent. The optimal bed depth of the primary adsorbent, determined from a diffusion study, was found to be 2.3 cm. The measured value for the effective diffusion coefficient of RN in a peat-based charcoal at 15% humidity and 25{degrees}C is 7.97 x 10(-10) m2 s-1. Exposures to 70% humidity for 7 d increased the buildup time-constant of Rn in the R-Canisters by 33% as compared to R-Canisters exposed to 15% humidity. At relative humidities ranging from 15-70%, the {sup 222}Rn buildup time-constant of the R-Canister ranged from 43-94 h, whereas the desorption time-constant ranged from 46-64 h. Typical buildup time-constants and desorption time-constants for conventional fully-opened charcoal canisters currently in field use ranged from 30-43 h and 17-29 h, respectively, over the same range of humidities.

  10. Role of charcoal tattooing in localization of recurred papillary thyroid carcinoma: initial experiences

    PubMed Central

    Kwon, Hyungju; Tae, Soon Young; Kim, Su-Jin; Jung, Kyeong Cheon; Kim, Ji-Hoon; Youn, Yeo-Kyu

    2015-01-01

    Purpose Surgical excision is the definitive treatment for localized recurrence of papillary thyroid carcinoma. Reoperation for recurrence, however, is challenging and associated with increased operative times and complication rates. For safe and effective reoperation, ultrasound-guided charcoal tattooing localization can be used. The aim of this study was to investigate the feasibility and safety of the ultrasound-guided charcoal tattooing localization. Methods Between November 2012 and August 2013, ten patients underwent preoperative charcoal tattooing localization for twelve recurrent lesions. Patient demographics, pathologic features, and operation results were reviewed. Results The technical success rate of charcoal tattooing was 100%. Eight patients had one recurrent lesion, and two patients had double lesions. Among these 12 recurrent lesions, three (25%) were found in level II, four (33%) in level IV, four (33%) in level VI, and one (8%) was found in the thyroidectomy bed site. The mean size of lesions was 0.87 ± 0.35 cm. Of these 10 patients, eight patients underwent selective lymph node dissection, one patient underwent modified radical neck dissection, and one patient underwent recurrent mass excision. Transient hypocalcemia developed in one patient, and no recurrent laryngeal nerve palsy occurred. There were no major complications related to the injection of the charcoal. The mean follow-up period after reoperation was 8.6 ± 2.7 months; in the follow-up ultrasound, there were no remnant lesions in all patients. Conclusion Preoperative ultrasound-guided charcoal tattooing localization for recurrent thyroid cancer appears to be a feasible and safe procedure for reoperation. Further evaluation is warranted in larger patients' cohorts. PMID:25741493

  11. The oxidative potential of PM10 from coal, briquettes and wood charcoal burnt in an experimental domestic stove

    NASA Astrophysics Data System (ADS)

    Shao, Longyi; Hou, Cong; Geng, Chunmei; Liu, Junxia; Hu, Ying; Wang, Jing; Jones, Tim; Zhao, Chengmei; BéruBé, Kelly

    2016-02-01

    Coal contains many potentially harmful trace elements. Coal combustion in unvented stoves, which is common in most parts of rural China, can release harmful emissions into the air that when inhaled cause health issues. However, few studies have dealt specifically with the toxicological mechanisms of the particulate matter (PM) released by coal and other solid fuel combustion. In this paper, PM10 particles that were generated during laboratory stove combustion of raw powdered coal, clay-mixed honeycomb briquettes, and wood charcoal were analysed for morphology, trace element compositions, and toxicity as represented by oxidative DNA damage. The analyses included Field Emission Scanning Electron Microscopy (FESEM), Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Plasmid Scission Assay (PSA). Gravimetric analysis indicated that the equivalent mass concentration of PM10 emitted by burning raw powdered coal was higher than that derived by burning honeycomb briquette. FESEM observation revealed that the coal burning-derived PM10 particles were mainly soot aggregates. The PSA results showed that the PM10 emitted by burning honeycomb briquettes had a higher oxidative capacity than that from burning raw powdered coal and wood charcoal. It is also demonstrated that the oxidative capacity of the whole particle suspensions were similar to those of the water soluble fractions; indicating that the DNA damage induced by coal burning-derived PM10 were mainly a result of the water-soluble fraction. An ICP-MS analysis revealed that the amount of total analysed water-soluble elements in the PM10 emitted by burning honeycomb briquettes was higher than that in PM produced by burning raw powdered coal, and both were higher than PM from burning wood charcoal. The total analysed water-soluble elements in these coal burning-derived PM10 samples had a significantly positive correlation with the level of DNA damage; indicating that the oxidative capacity of the coal burning

  12. Mass spectrometric detection of ricin and its activity in food and clinical samples.

    PubMed

    Kalb, Suzanne R; Barr, John R

    2009-03-15

    Ricin is a potent toxin capable of inhibiting protein synthesis and causing death or respiratory failure. Because of its high availability and lethality, ricin is considered a likely agent for bioterrorism. Rapidly determining contamination of food product with ricin and human exposure to ricin is therefore an important public health goal. In this work, we report the development of a method that detects ricin and its activity in food or clinical samples. This method involves immunocapture of the toxin, an examination of the activity of the ricin protein upon a DNA substrate that mimics the toxin's natural RNA target, and analysis of tryptic fragments of the toxin itself. It is the combination of these three techniques, all performed on the same sample, which allows for a sensitive and selective analysis of ricin isolated from a food or clinical sample. This measurement includes a measure of the toxin's activity. The utility of this method was demonstrated on ricin spiked into food and clinical samples consisting of milk, apple juice, serum, and saliva. PMID:19228034

  13. Activity concentrations of environmental samples collected in Fukushima Prefecture immediately after the Fukushima nuclear accident

    PubMed Central

    Hosoda, Masahiro; Tokonami, Shinji; Tazoe, Hirofumi; Sorimachi, Atsuyuki; Monzen, Satoru; Osanai, Minoru; Akata, Naofumi; Kakiuchi, Hideki; Omori, Yasutaka; Ishikawa, Tetsuo; Sahoo, Sarata K.; Kovács, Tibor; Yamada, Masatoshi; Nakata, Akifumi; Yoshida, Mitsuaki; Yoshino, Hironori; Mariya, Yasushi; Kashiwakura, Ikuo

    2013-01-01

    Radionuclide concentrations in environmental samples such as surface soils, plants and water were evaluated by high purity germanium detector measurements. The contribution rate of short half-life radionuclides such as 132I to the exposure dose to residents was discussed from the measured values. The highest values of the 131I/137Cs activity ratio ranged from 49 to 70 in the environmental samples collected at Iwaki City which is located to the south of the F1-NPS. On the other hand, the 132I/131I activity ratio in the same environmental samples had the lowest values, ranging from 0.01 to 0.02. By assuming that the 132I/131I activity ratio in the atmosphere was equal to the ratio in the environmental samples, the percent contribution to the thyroid equivalent dose by 132I was estimated to be less than 2%. Moreover, the contribution to the thyroid exposure by 132I might be negligible if 132I contamination was restricted to Iwaki City. PMID:23887080

  14. A Sample/Population Size Activity: Is It the Sample Size of the Sample as a Fraction of the Population that Matters?

    ERIC Educational Resources Information Center

    Smith, Margaret H.

    2004-01-01

    Unless the sample encompasses a substantial portion of the population, the standard error of an estimator depends on the size of the sample, but not the size of the population. This is a crucial statistical insight that students find very counterintuitive. After trying several ways of convincing students of the validity of this principle, I have…

  15. In Situ NDA Conformation Measurements Performed at Auxiliary Charcoal Bed and Other Main Charcoal Beds After Uranium Removal from Molten Salt Reactor Experiment ACB at Oak Ridge National Laboratory

    SciTech Connect

    Haghighi, M. H.; Kring, C. T.; McGehee, J. T.; Jugan, M. R.; Chapman, J.; Meyer, K. E.

    2002-02-26

    The Molten Salt Reactor Experiment (MSRE) site is located in Tennessee, on the U.S. Department of Energy (DOE) Oak Ridge Reservation (ORR). The MSRE was run by Oak Ridge National Laboratory (ORNL) to demonstrate the desirable features of the molten-salt concept in a practical reactor that could be operated safely and reliably. It introduced the idea of a homogeneous reactor using fuel salt media and graphite moderation for power and breeder reactors. The MSRE reactor and associated components are located in cells beneath the floor in the high-bay area of Building 7503. The reactor was operated from June 1965 to December 1969. When the reactor was shut down, fuel salt was drained from the reactor circuit to two drain tanks. A ''clean'' salt was then circulated through the reactor as a decontamination measure and drained to a third drain tank. When operations ceased, the fuel and flush salts were allowed to cool and solidify in the drain tanks. At shutdown, the MSRE facility complex was placed in a surveillance and maintenance program. Beginning in 1987, it was discovered that gaseous uranium (U-233/U-232) hexafluoride (UF6) had moved throughout the MSRE process systems. The UF6 had been generated when radiolysis in the fluorine salts caused the individual constituents to dissociate to their component atoms, including free fluorine. Some of the free fluorine combined with uranium fluorides (UF4) in the salt to produce UF6. UF6 is gaseous at slightly above ambient temperatures; thus, periodic heating of the fuel salts (which was intended to remedy the radiolysis problems) and simple diffusion had allowed the UF6 to move out of the salt and into the process systems of MSRE. One of the systems that UF6 migrated into due to this process was the offgas system which is vented to the MSRE main charcoal beds and MSRE auxiliary charcoal bed (ACB). Recently, the majority of the uranium laden-charcoal material residing within the ACB was safely and successfully removed using

  16. Identification of Volatile Organic Compounds (VOCs) From Photochemical Activity in Snow Samples

    NASA Astrophysics Data System (ADS)

    Kos, G.; Ariya, P. A.

    2004-05-01

    The occurrence of VOCs in snow has been observed and can be related to anthropogenic emissions and biological activity. Photochemistry and microorganisms play a major role in the transformation of compounds in different compartments of the global ecosystem. Studies so far focused on the determination of single analytes or a class of compounds - mainly of anthropogenic origin (e.g. halogenated aromatic hydrocarbons) - that were considered important with regard to health and environmental concerns. Broader studies that describe a range of different compounds with different functionalities are relatively rare, especially for those of biological origin. The presented study investigated the formation of VOCs in snow samples and their connection with microbiological activity. The main aim was to pre-concentrate, identify and quantify volatile organic compounds. Snow samples were collected in an urban environment (Montreal, Canada) with sterilized containers. Samples were transferred into a heated reaction flask, where the sample was melted. A two-trap system was employed for pre-concentration: The first trap was used for water removal. The second trap was used for the collection of expected analytes by removing volatiles from the circulating air. Circulation was maintained with a pump at atmospheric pressure. Adsorption to glass walls of the reaction flask was prevented with halocarbon wax coating. Different sterilization methods were employed to suppress microbiological activity in order to collect background data and identify compounds of biological origin. VOC concentration and compound identification was performed with gas chromatography and mass spectrometric detection (GC-MS) by taking a sample with a gas-tight syringe through a septum-port. The sample was directly injected into the GC system. Compounds were identified by their respective mass spectra and included aldehydes and alcohols.

  17. The charcoal trap: Miombo forests and the energy needs of people

    PubMed Central

    2011-01-01

    Background This study evaluates the carbon dioxide and other greenhouse gas fluxes to the atmosphere resulting from charcoal production in Zambia. It combines new biomass and flux data from a study, that was conducted in a miombo woodland within the Kataba Forest Reserve in the Western Province of Zambia, with data from other studies. Results The measurements at Kataba compared protected area (3 plots) with a highly disturbed plot outside the forest reserve and showed considerably reduced biomass after logging for charcoal production. The average aboveground biomass content of the reserve (Plots 2-4) was around 150 t ha-1, while the disturbed plot only contained 24 t ha-1. Soil carbon was not reduced significantly in the disturbed plot. Two years of eddy covariance measurements resulted in net ecosystem exchange values of -17 ± 31 g C m-2 y-1, in the first and 90 ± 16 g C m-2 in the second year. Thus, on the basis of these two years of measurement, there is no evidence that the miombo woodland at Kataba represents a present-day carbon sink. At the country level, it is likely that deforestation for charcoal production currently leads to a per capita emission rate of 2 - 3 t CO2 y-1. This is due to poor forest regeneration, although the resilience of miombo woodlands is high. Better post-harvest management could change this situation. Conclusions We argue that protection of miombo woodlands has to account for the energy demands of the population. The production at national scale that we estimated converts into 10,000 - 15,000 GWh y-1 of energy in the charcoal. The term "Charcoal Trap" we introduce, describes the fact that this energy supply has to be substituted when woodlands are protected. One possible solution, a shift in energy supply from charcoal to electricity, would reduce the pressure of forests but requires high investments into grid and power generation. Since Zambia currently cannot generate this money by itself, the country will remain locked in the

  18. Decolorization of indigo carmine by charcoal from extracted residue of coffee beans.

    PubMed

    Nakamura, Takeo; Hirata, Mizuho; Kawasaki, Naohito; Tanada, Seiki; Tamura, Takamichi; Nakahori, Yutaka

    2003-03-01

    The adsorption ability of charcoal from extracted residue of coffee beans for indigo carmine removal was investigated by the batch method. Differences in the removal ratio and removal rate of indigo carmine could be explained by differences in the properties of charcoal. In the relationship between the amount of indigo carmine adsorbed and the square root of elapsed time, a good linearity was recognized. Since the relationship between the amount of indigo carmine adsorbed and square root of elapsed time showed a good linearity, the intraparticle diffusion of indigo carmine onto pores of adsorbents was identified as the rate-limiting step in the adsorption process. PMID:12680583

  19. Holocene Fire History of an Eastern Oregon Forest Based on Soil Charcoal Radiocarbon Dates

    NASA Astrophysics Data System (ADS)

    Carson, R. J.; Malkemus, D.; Clifton, C. F.

    2006-12-01

    Limited research has been done on long-term forest fire histories in northeastern Oregon. As part of an investigation to determine the minimum age of a 300 ha landslide in the Blue Mountains, a pit was excavated near the toe of the slide. The pit, located in a depression between the landslide and a ridge, contains massive clays and silts, and an 8000-year sequence of forest fires recorded in 7 buried charcoal layers. Eight- thousand-year-old Mazama Ash (Crater Lake, Oregon) is common in the area, but no tephra was found in the excavation. The upper 17 cm is organic rich soil. Seven horizons of charcoal are present; the upper six are subhorizontal and occur at depths of 17, 36, 41, 46, 52, and 57 cm. The lowest charcoal horizon follows a disconformity that cuts diagonally across the pit from 85 to 125 cm below the surface; oxidation in the form of orange mottling occurs above this disconformity (interpreted to be a paleoslope) and is prominent below it. The charcoal horizons provide evidence of large-scale forest fires in the vicinity, with differing intensities represented by the amount of charcoal in each horizon. The layers vary in thickness from 2 to 6 cm. Five charcoal horizons were radiocarbon dated (AMS) and calendar calibrated. The charcoal at the base of the soil (at 17 cm) provided an age of AD 1670 to 1960; this horizon correlates with widespread fires in the Blue Mountains in AD 1855. The horizon second closest to the surface (at 36 cm) provided an age of 1310 ± 40 B.P. The thickest horizon (at 46 cm) yielded an age of 2420 ± 40 B.P. The lowest horizontal horizon (at 57 cm) provided an age of 3460 ± 40 B.P. The lowest charcoal (at the disconformity) yielded an age of 7990 ± 40 B.P. Based on radiocarbon dates, the mean rate of sedimentation in the closed depression is approximately 1.2 cm/century. Fire episodes (which correspond remarkably well with a lake core site approximately 150 km south), indicate relatively long periods (from 400 to over 4000

  20. Avoidance and activation as keys to depression: adaptation of the Behavioral Activation for Depression Scale in a Spanish sample.

    PubMed

    Barraca, Jorge; Pérez-Alvarez, Marino; Lozano Bleda, José Héctor

    2011-11-01

    In this paper we present the adaptation of the Behavioral Activation for Depression Scale (BADS), developed by Kanter, Mulick, Busch, Berlin, and Martell (2007), in a Spanish sample. The psychometric properties were tested in a sample of 263 participants (124 clinical and 139 non-clinical). The results show that, just as in the original English version, the Spanish BADS is a valid and internally consistent scale. Construct validity was examined by correlation with the BDI-II, AAQ, ATQ, MCQ-30, STAI and EROS. Factor analysis justified the four-dimensions of the original instrument (Activation, Avoidance/Rumination, Work/School Impairment and Social Impairment), although with some differences in the factor loadings of the items. Further considerations about the usefulness of the BADS in the clinical treatment of depressed patients are also suggested. PMID:22059343

  1. ROTATION AND MAGNETIC ACTIVITY IN A SAMPLE OF M-DWARFS

    SciTech Connect

    Browning, Matthew K.; Basri, Gibor; Marcy, Geoffrey W.; Zhang Jiahao West, Andrew A

    2010-02-15

    We have analyzed the rotational broadening and chromospheric activity in a sample of 123 M-dwarfs, using spectra taken at the W.M. Keck Observatory as part of the California Planet Search program. We find that only seven of these stars are rotating more rapidly than our detection threshold of v sin i {approx} 2.5 km s{sup -1}. Rotation appears to be more common in stars later than M3 than in the M0-M2.5 mass range: we estimate that less than 10% of early-M stars are detectably rotating, whereas roughly a third of those later than M4 show signs of rotation. These findings lend support to the view that rotational braking becomes less effective in fully convective stars. By measuring the equivalent widths of the Ca II H and K lines for the stars in our sample, and converting these to approximate L {sub Ca}/L {sub bol} measurements, we also provide constraints on the connection between rotation and magnetic activity. Measurable rotation is a sufficient, but not necessary condition for activity in our sample: all the detectable rotators show strong Ca II emission, but so too do a small number of non-rotating stars, which we presume may lie at high inclination angles relative to our line of sight. Our data are consistent with a 'saturation-type' rotation-activity relationship, with activity roughly independent of rotation above a threshold velocity of less than 6 km s{sup -1}. We also find weak evidence for a 'gap' in L {sub Ca}/L {sub bol} between a highly active population of stars, which typically are detected as rotators, and another much less active group.

  2. A novel method for measuring aromatase activity in tissue samples by determining estradiol concentrations.

    PubMed

    Tinwell, H; Rascle, J B; Colombel, S; Al Khansa, I; Freyberger, A; Bars, R

    2011-07-01

    Increasing scrutiny of endocrine disrupters has led to changes to European pesticide and biocide legislation and to the introduction of the Endocrine Disrupter Screening Program by the US EPA. One element of endocrine disrupter identification is to determine its effects on aromatase, but most available assays are limited as they depend on tritiated water production to indicate enzyme activity. Whilst acceptable for determining aromatase effects using a cell-free approach, this method is unreliable for cell or tissue-based investigations as other cytochrome P-450 isoenzyme activities can similarly produce tritiated water and consequently confound interpretation of the aromatase data. To address this lack of specificity an assay directly measuring the final estrogen product by incubating rat tissue protein with testosterone and measuring the resultant estradiol concentration was developed. Using this approach we demonstrated marked increases in enzyme activity in pregnant rat ovary samples and dose-related inhibitions when incubating non-pregnant rat ovary samples with known aromatase inhibitors. Hepatic aromatase activity was investigated using our method and by tritiated water production with microsomes from rats dosed with the antiandrogen 1,1-dichloro-2,2-bis(4 chlorophenyl)ethane. Additional cytochrome P-450s were also measured. Treatment-related increased tritiated water production and general hepatic enzyme activity were recorded but estradiol was not increased, indicating that the increased tritiated water was due to general enzyme activity and not aromatase activity. A simple and specific method has been developed that can detect aromatase inhibition and induction, which when applied to tissue samples, provides a means of generating relevant animal data concerning chemical effects on the aromatase enzyme. PMID:21259292

  3. 75 FR 48644 - Certain Activated Carbon From the People's Republic of China: Notice of Partial Rescission of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-11

    ... Reviews, 75 FR 29976-29980 (May 28, 2010) (``Initiation''). On June 15, 2010, Calgon Carbon Corporation... Limited; Longyan Wanan Activated Carbon; Nanjing Mulinsen Charcoal; Nantong Ameriasia Advanced...

  4. Associations between physical activity and other health behaviors in a representative sample of US adolescents.

    PubMed Central

    Pate, R R; Heath, G W; Dowda, M; Trost, S G

    1996-01-01

    OBJECTIVES: This study examined the associations between physical activity and other health behaviors in a representative sample of US adolescents. METHODS: In the 1990 Youth Risk Behavior Survey, 11631 high school students provided information on physical activity; diet; substance use; and other negative health behaviors. Logistic regression analyses examined associations between physical activity and other health behaviors in a subset of 2652 high-active and 1641 low-active students. RESULTS: Low activity was associated with cigarette smoking, marijuana use, lower fruit and vegetable consumption, greater television watching, failure to wear a seat belt, and low perception of academic performance. For consumption of fruit, television watching, and alcohol consumption, significant interactions were found with race/ethnicity or sex, suggesting that sociocultural factors may affect the relationships between physical activity and some health behaviors. CONCLUSIONS: Low physical activity was associated with several other negative health behaviors in teenagers. Future studies should examine whether interventions for increasing physical activity in youth can be effective in reducing negative health behaviors. PMID:8916523

  5. Radio observations of a hard X-ray selected sample of active galaxies

    NASA Technical Reports Server (NTRS)

    Unger, S. W.; Lawrence, A.; Wilson, A. S.; Elvis, M.; Wright, A. E.

    1987-01-01

    Radio observations of a hard X-ray selected sample of active galaxies obtained with the VLA and Parkes radio telescopes are discussed, and the ratio of the radio to X-ray flux density is used to determine the degree of radio-loudness of the galaxies. A continuous distribution of the degree of radio loudness is found amongst the sample galaxies, and no evidence for distinct radio-quiet and radio-loud populations is noted. The X-ray and radio luminosity is shown to be nonlinearly correlated, with the radio-loud objects all having high X-ray luminosity.

  6. Effects of Seed Treatment, In-Furrow Sprays, and Herbicides Treatments on Charcoal Rot of June-Planted Soybean, 2007

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Evaluation of chemical and biological fungicides to control charcoal rot of soybean was conducted in a field planted annually to soybean or snap bean since 2002 with moderate to high seedling disease losses to charcoal rot. Seed treatment slurries were created by adding distilled water to the test ...

  7. What Does Psychological Autopsy Study Tell Us about Charcoal Burning Suicide--A New and Contagious Method in Asia?

    ERIC Educational Resources Information Center

    Chan, Sandra S. M.; Chiu, Helen F. K.; Chen, Eric Y. H.; Chan, Wincy S. C.; Wong, Paul W. C.; Chan, Cecilia L. W.; Law, Y. W.; Yip, Paul S. F.

    2009-01-01

    Charcoal burning suicides in Hong Kong between 2002-2004 in the 15 to 59-year-old age group were investigated using the psychological autopsy method. The psychopathological profiles of charcoal burning suicides (N = 53) were compared against "other suicides" (N = 97). The two groups did not differ significantly in the prevalence of "DSM-IV" axis I…

  8. USE OF POWDERED COCONUT CHARCOAL AS A TOXICITY IDENTIFICATION AND EVALUATION MANIPULATION FOR ORGANIC TOXICANTS IN MARINE SEDIMENTS

    EPA Science Inventory

    We report on a procedure using powdered coconut charcoal to sequester organic contaminants and reduce toxicity in sediments as part of a series of toxicity identification and evaluation (TIE) methods. Powdered coconut charcoal (PCC) was effective in reducing the toxicity of endos...

  9. Accurate measurement of bromine contents in plastic samples by instrumental neutron activation analysis.

    PubMed

    Kim, I J; Lee, K S; Hwang, E; Min, H S; Yim, Y H

    2013-03-26

    Accurate measurements of bromine contents in plastic samples were made by the direct comparator instrumental neutron activation analysis (INAA). Individual factors affecting the measurements were comprehensively evaluated and compensated, including the volatility loss of bromine from standard comparators, the background bromine level in the filter papers used for preparation of the standard comparators, nuclear interference, γ-ray spectral interference and the variance among replicates of the samples. Uncertainty contributions from those factors were thoroughly evaluated and included in the uncertainty budgeting of the INAA measurement. (81)Br was chosen as the target isotope, and the INAA measurements for bromine were experimentally confirmed to exhibit good linearity within a bromine content range of 10-170 μg. The established method has been applied to the analysis of eight plastic samples: four commercially available certified reference materials (CRMs) of polyethylene and polystyrene and four acrylonitrile butadiene styrene (ABS) samples prepared as the candidate reference materials (KRISS CRM 113-01-012, -013, -014 and -015). The bromine contents of the samples were calculated at three different γ-ray energies and compared, showing good agreement. The results of the four CRMs also showed good consistency with their certified values within the stated uncertainties. Finally, the bromine contents of the ABS samples were determined with expanded uncertainties (at a 95% level of confidence) between 2.5% and 5% in a bromine content range of 25-900 mg kg(-1). PMID:23498117

  10. Phosphatase activity in Antarctica soil samples as a biosignature of extant life

    NASA Astrophysics Data System (ADS)

    Sato, Shuji; Itoh, Yuki; Takano, Yoshinori; Fukui, Manabu; Kaneko, Takeo; Kobayashi, Kensei

    Microbial activities have been detected in such extreme terrestrial environments as deep lithosphere, a submarine hydrothermal systems, stratosphere, and Antarctica. Microorganisms have adapted to such harsh environments by evolving their biomolecules. Some of these biomolecules such as enzymes might have different characteristics from those of organisms in ordinary environments. Many biosignatures (or biomarkers) have been proposed to detect microbial activities in such extreme environments. A number of techniques are proposed to evaluate biological activities in extreme environments including cultivation methods, assay of metabolism, and analysis of bioorganic compounds like amino acids and DNA. Enzyme activities are useful signature of extant life in extreme environments. Among many enzymes, phosphatase could be a good indicator of biological activities, since phosphate esters are essential for all the living terrestrial organisms. In addition, alkaline phosphatase is known as a typical zinc-containing metalloenzyme and quite stable in environments. We analyzed phosphatase activities in Antarctica soil samples to see whether they can be used as biosignatures for extant life. In addition, we characterized phosphatases extracted from the Antarctica soil samples, and compared with those obtained from other types of environments. Antarctica surface environments are quite severe environments for life since it is extremely cold and dry and exposed to strong UV and cosmic rays. We tried to evaluate biological activities in Antarctica by measuring phosphatase activities. Surface soil samples are obtained at the Sites 1-8 near Showa Base in Antarctica during the 47th Japan Antarctic exploration mission in 2005-6. Activities of acid phosphatase (ACP) and alkaline phosphatase (ALP) are measured spectrophotometrically after mixing the powdered sample and p-nitrophenyl phosphate solution (pH 6.5 for ACP, pH 8.0 for ALP). ALP was characterized after extraction from soils with

  11. Limitations of protein-coated charcoal in the separation of free from bound vitamin B12 in serum.

    PubMed Central

    Jacob, E; Wong, K T

    1983-01-01

    The effect of haemoglobin and albumin-coated charcoal on the concentration of vitamin B12 binding proteins in serum has been investigated. As commonly employed, coated charcoal removes a significant amount of transcobalamin II (TCII) from serum, but does not affect transcobalamin I and III (TCI and III). Increasing the protein coat up to about 10 mg of protein per 25 mg of charcoal reduces the adsorption of TCII, but increasing the protein concentration beyond this has little added effect. The amount of adsorption is proportional to the amount of coated charcoal employed, but even small amounts adsorb some TCII. These results indicate that protein-coated charcoal is not the ideal way of separating free from bound vitamin B12 in serum; it cannot reliably be used for the measurement of the concentration of apo-TCII but can be employed for the measurement of apo-TCI and III. PMID:6886019

  12. Activity sampling of nurses of a sub-acute ward of a large hospital.

    PubMed

    Bobdey, C S; Sandhu, M S; Urmil, A C; Dayakar, T

    1992-07-01

    A study was conducted in a 43 bedded subacute family ward of a large hospital to find out the adequacy and efficiency of its nursing service. Activity analysis in respect of nurses was carried out by Activity Sampling Technique. The study revealed that out of 334 activities, observed, 78 (23.3%) were non-productive, whereas 256 (76.7%) were productive. Out of the productive activities, 148 (44.3%) were for direct patient care mainly comprising of 46 (31.1% for carrying out technical procedures, 36 (24.32%) for determining patients' needs, 20 (13.15%) for preparing patients for various procedures and 15 (10.14%) for assisting in technical procedures. Number wise the nurses were found to be adequate. PMID:10130935

  13. Predicting Antitumor Activity of Peptides by Consensus of Regression Models Trained on a Small Data Sample

    PubMed Central

    Radman, Andreja; Gredičak, Matija; Kopriva, Ivica; Jerić, Ivanka

    2011-01-01

    Predicting antitumor activity of compounds using regression models trained on a small number of compounds with measured biological activity is an ill-posed inverse problem. Yet, it occurs very often within the academic community. To counteract, up to some extent, overfitting problems caused by a small training data, we propose to use consensus of six regression models for prediction of biological activity of virtual library of compounds. The QSAR descriptors of 22 compounds related to the opioid growth factor (OGF, Tyr-Gly-Gly-Phe-Met) with known antitumor activity were used to train regression models: the feed-forward artificial neural network, the k-nearest neighbor, sparseness constrained linear regression, the linear and nonlinear (with polynomial and Gaussian kernel) support vector machine. Regression models were applied on a virtual library of 429 compounds that resulted in six lists with candidate compounds ranked by predicted antitumor activity. The highly ranked candidate compounds were synthesized, characterized and tested for an antiproliferative activity. Some of prepared peptides showed more pronounced activity compared with the native OGF; however, they were less active than highly ranked compounds selected previously by the radial basis function support vector machine (RBF SVM) regression model. The ill-posedness of the related inverse problem causes unstable behavior of trained regression models on test data. These results point to high complexity of prediction based on the regression models trained on a small data sample. PMID:22272081

  14. Predicting antitumor activity of peptides by consensus of regression models trained on a small data sample.

    PubMed

    Radman, Andreja; Gredičak, Matija; Kopriva, Ivica; Jerić, Ivanka

    2011-01-01

    Predicting antitumor activity of compounds using regression models trained on a small number of compounds with measured biological activity is an ill-posed inverse problem. Yet, it occurs very often within the academic community. To counteract, up to some extent, overfitting problems caused by a small training data, we propose to use consensus of six regression models for prediction of biological activity of virtual library of compounds. The QSAR descriptors of 22 compounds related to the opioid growth factor (OGF, Tyr-Gly-Gly-Phe-Met) with known antitumor activity were used to train regression models: the feed-forward artificial neural network, the k-nearest neighbor, sparseness constrained linear regression, the linear and nonlinear (with polynomial and Gaussian kernel) support vector machine. Regression models were applied on a virtual library of 429 compounds that resulted in six lists with candidate compounds ranked by predicted antitumor activity. The highly ranked candidate compounds were synthesized, characterized and tested for an antiproliferative activity. Some of prepared peptides showed more pronounced activity compared with the native OGF; however, they were less active than highly ranked compounds selected previously by the radial basis function support vector machine (RBF SVM) regression model. The ill-posedness of the related inverse problem causes unstable behavior of trained regression models on test data. These results point to high complexity of prediction based on the regression models trained on a small data sample. PMID:22272081

  15. Automated sample preparation for ICP analysis of active pharmaceutical ingredients and intermediates.

    PubMed

    Sims, Jonathan; Smith, Andrew; Patel, Dharmista; Batchelor, Richard; Carreira, Judith

    2011-10-01

    Routine testing of active pharmaceutical ingredients (APIs) for metal residues is an expectation of regulatory bodies such as the FDA (U.S. Food and Drug Administration). Sample preparation techniques are the rate-limiting step in the testing process and can be variable depending on the specific characteristics of the API under test. Simplification and standardization of the routine preparation of inductively coupled plasma spectroscopy sample solutions of organic compounds has been developed using a commercially available robotic workstation. Contamination from the metal components of the instrument and from sample tubes used in the methodology has been studied using a Design of Experiments approach. The optimized method described can be used for the measurement of trace metals in Pharmaceuticals at levels compliant with European and U.S. regulatory requirements. PMID:21906564

  16. A neutron activation analysis procedure for the determination of uranium, thorium and potassium in geologic samples

    USGS Publications Warehouse

    Aruscavage, P. J.; Millard, H.T., Jr.

    1972-01-01

    A neutron activation analysis procedure was developed for the determination of uranium, thorium and potassium in basic and ultrabasic rocks. The three elements are determined in the same 0.5-g sample following a 30-min irradiation in a thermal neutron flux of 2??1012 n??cm-2??sec-1. Following radiochemical separation, the nuclides239U (T=23.5 m),233Th (T=22.2 m) and42K (T=12.36 h) are measured by ??-counting. A computer program is used to resolve the decay curves which are complex owing to contamination and the growth of daughter activities. The method was used to determine uranium, throium and potassium in the U. S. Geological Survey standard rocks DTS-1, PCC-1 and BCR-1. For 0.5-g samples the limits of detection for uranium, throium and potassium are 0.7, 1.0 and 10 ppb, respectively. ?? 1972 Akade??miai Kiado??.

  17. Diminishing relative jitter in electrooptic sampling of active mm-wave and THz circuits.

    PubMed

    Jamshidifar, M; Bolívar, P Haring

    2013-02-25

    In this work a novel approach in synchronization of electrooptic sampling systems for the ultra-broadband characterization of active mm-wave and THz devices is presented. The relative time jitter between sampled circuit and probing electrooptic head is eliminated by using a femtosecond laser system both as the generator of CW driving the device under test as well as the impulsively probing element. Previous ultra-broadband approaches were applicable to passive components driven by THz impulses, only. The presented system is more generally applicable to active mm-wave and THz components driven by conventional CW electronic sources. Broadband analysis on silicon nonlinear transmission line elements up to a frequency of 300 GHz is presented in order to illustrate the capabilities of the concept. PMID:23481973

  18. Epithermal Neutron Activation Analysis of Some Geological Samples of Different Origin

    SciTech Connect

    Duliu, O. G.; Cristache, C. I.; Oaie, G.; Ricman, C.; Culicov, O. A.; Frontasyeva, M. V.

    2010-01-21

    Instrumental Epithermal Neutron Activation Analysis was used to investigate the distribution of six major elements and 34 trace elements in a set of eight igneous and metamorphic rocks collected from Carpathian and Macin Mountainsas well as unconsolidated sediments collected from anoxic zone of the Black Sea. All experimental data were interpreted within the Upper Continental Core and Mid Ocean Ridge Basalt model system that allowed getting more information concerning samples origin as well as the environmental peculiarities.

  19. Characterization of Tank 48H Samples for Alpha Activity and Actinide Isotopics

    SciTech Connect

    Hobbs, D.T.; Coleman, C.J.; Hay, M.S.

    1995-12-04

    This document reports the total alpha activity and actinide isotopic results for samples taken from Tank 48H prior to the addition of sodium tetraphenylborate and MST in Batch {number_sign}1 of the ITP process. This information used to determine the quantity of MST for Batch {number_sign}1 of the ITP process and the total actinide content in the tank for dose calculations.

  20. Geochemical signature of land-based activities in Caribbean coral surface samples

    USGS Publications Warehouse

    Prouty, N.G.; Hughen, K.A.; Carilli, J.

    2008-01-01

    Anthropogenic threats, such as increased sedimentation, agrochemical run-off, coastal development, tourism, and overfishing, are of great concern to the Mesoamerican Caribbean Reef System (MACR). Trace metals in corals can be used to quantify and monitor the impact of these land-based activities. Surface coral samples from the MACR were investigated for trace metal signatures resulting from relative differences in water quality. Samples were analyzed at three spatial scales (colony, reef, and regional) as part of a hierarchical multi-scale survey. A primary goal of the paper is to elucidate the extrapolation of information between fine-scale variation at the colony or reef scale and broad-scale patterns at the regional scale. Of the 18 metals measured, five yielded statistical differences at the colony and/or reef scale, suggesting fine-scale spatial heterogeneity not conducive to regional interpretation. Five metals yielded a statistical difference at the regional scale with an absence of a statistical difference at either the colony or reef scale. These metals are barium (Ba), manganese (Mn), chromium (Cr), copper (Cu), and antimony (Sb). The most robust geochemical indicators of land-based activities are coral Ba and Mn concentrations, which are elevated in samples from the southern region of the Gulf of Honduras relative to those from the Turneffe Islands. These findings are consistent with the occurrence of the most significant watersheds in the MACR from southern Belize to Honduras, which contribute sediment-laden freshwater to the coastal zone primarily as a result of human alteration to the landscape (e.g., deforestation and agricultural practices). Elevated levels of Cu and Sb were found in samples from Honduras and may be linked to industrial shipping activities where copper-antimony additives are commonly used in antifouling paints. Results from this study strongly demonstrate the impact of terrestrial runoff and anthropogenic activities on coastal water

  1. Geochemical signature of land-based activities in Caribbean coral surface samples

    NASA Astrophysics Data System (ADS)

    Prouty, N. G.; Hughen, K. A.; Carilli, J.

    2008-12-01

    Anthropogenic threats, such as increased sedimentation, agrochemical run-off, coastal development, tourism, and overfishing, are of great concern to the Mesoamerican Caribbean Reef System (MACR). Trace metals in corals can be used to quantify and monitor the impact of these land-based activities. Surface coral samples from the MACR were investigated for trace metal signatures resulting from relative differences in water quality. Samples were analyzed at three spatial scales (colony, reef, and regional) as part of a hierarchical multi-scale survey. A primary goal of the paper is to elucidate the extrapolation of information between fine-scale variation at the colony or reef scale and broad-scale patterns at the regional scale. Of the 18 metals measured, five yielded statistical differences at the colony and/or reef scale, suggesting fine-scale spatial heterogeneity not conducive to regional interpretation. Five metals yielded a statistical difference at the regional scale with an absence of a statistical difference at either the colony or reef scale. These metals are barium (Ba), manganese (Mn), chromium (Cr), copper (Cu), and antimony (Sb). The most robust geochemical indicators of land-based activities are coral Ba and Mn concentrations, which are elevated in samples from the southern region of the Gulf of Honduras relative to those from the Turneffe Islands. These findings are consistent with the occurrence of the most significant watersheds in the MACR from southern Belize to Honduras, which contribute sediment-laden freshwater to the coastal zone primarily as a result of human alteration to the landscape (e.g., deforestation and agricultural practices). Elevated levels of Cu and Sb were found in samples from Honduras and may be linked to industrial shipping activities where copper-antimony additives are commonly used in antifouling paints. Results from this study strongly demonstrate the impact of terrestrial runoff and anthropogenic activities on coastal water

  2. Instrumental neutron activation analysis of soil and sediment samples from Siwa Oasis, Egypt

    NASA Astrophysics Data System (ADS)

    Badawy, Wael M.; Ali, Khaled; El-Samman, Hussein M.; Frontasyeva, Marina V.; Gundorina, Svetlana F.; Duliu, Octavian G.

    2015-07-01

    Instrumental neutron activation analysis was used to study geochemical peculiarities of the Siwa Oasis in the Western Egyptian Desert. A total of 34 elements were determined in soil and sediment samples (Na, Mg, Al, Cl, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Br, Rb, Sr, Zr, Sb, I, Cs, Ba, La, Ce, Nd, Eu, Tb, Dy, Tm, Yb, Hf, Ta, Th, and U). For data interpretation Cluster analysis was applied. Comparison with the available literature data was carried out.

  3. Paraoxonase-1 Enzyme Activity Assay for Clinical Samples: Validation and Correlation Studies

    PubMed Central

    Garelnabi, Mahdi; Younis, Abdelmoneim

    2015-01-01

    Background Paraoxonase-1 (PON1) enzyme is reported in various types of tissues and linked to numerous pathophysiological disorders. It is a potential biomarker in many pathological conditions such as cardiovascular diseases. Material/Methods We conducted several small-scale studies to evaluate PON1 performance as affected by sample types, storage, and interferences. We also carried out short-term studies to compare the performance of the widely used PON1 assay to the similar commercially available PON1 kit assay method; sample size for the method comparison was N=40, and the number varied for other validation experiments. Results Our studies using various types of anticoagulants show that samples collected in tubes with NaF, citrate, EDTA, clot activator, and sodium heparin have increased PON1 levels that are 49%, 24.5%, 19.8%, 11.4%, and 8%, respectively, higher compared to serum samples collected in plain tubes. However, samples collected in lithium heparin tubes demonstrated 10.4% lower PON1 levels compared to serum collected in plain tubes. Biological interference such as hemolysis has little effect on PON1 levels; however, samples spiked with lipids have shown 13% lower PON 1 levels. Our studies comparing the PON1 method commonly available for PON1 assay and a similar non-ELISA commercially available PON1 kit method showed a weak Spearman correlation coefficient of R2=0.40 for the range of 104.9–245.6 U/L. Conclusions The current study provides new validation data on enzyme PON1 performance. While no appreciable change was seen with storage, samples type affects the enzyme performance. Our results should encourage additional clinical studies to investigate other aspects of factors known to affect PON1 enzyme function and performance. PMID:25814092

  4. Active tactile sampling by an insect in a step-climbing paradigm

    PubMed Central

    Krause, André F.; Dürr, Volker

    2012-01-01

    Many insects actively explore their near-range environment with their antennae. Stick insects (Carausius morosus) rhythmically move their antennae during walking and respond to antennal touch by repetitive tactile sampling of the object. Despite its relevance for spatial orientation, neither the spatial sampling patterns nor the kinematics of antennation behavior in insects are understood. Here we investigate unrestrained bilateral sampling movements during climbing of steps. The main objectives are: (1) How does the antennal contact pattern relate to particular object features? (2) How are the antennal joints coordinated during bilateral tactile sampling? We conducted motion capture experiments on freely climbing insects, using steps of different height. Tactile sampling was analyzed at the level of antennal joint angles. Moreover, we analyzed contact patterns on the surfaces of both the obstacle and the antenna itself. Before the first contact, both antennae move in a broad, mostly elliptical exploratory pattern. After touching the obstacle, the pattern switches to a narrower and faster movement, caused by higher cycle frequencies and lower cycle amplitudes in all joints. Contact events were divided into wall- and edge-contacts. Wall contacts occurred mostly with the distal third of the flagellum, which is flexible, whereas edge contacts often occurred proximally, where the flagellum is stiff. The movement of both antennae was found to be coordinated, exhibiting bilateral coupling of functionally analogous joints [e.g., left head-scape (HS) joint with right scape-pedicel (SP) joint] throughout tactile sampling. In comparison, bilateral coupling between homologous joints (e.g., both HS joints) was significantly weaker. Moreover, inter-joint coupling was significantly weaker during the contact episode than before. In summary, stick insects show contact-induced changes in frequency, amplitude and inter-joint coordination during tactile sampling of climbed obstacles

  5. Formulation of a charcoal suspension for intratumoral injection. Study of galenical excipients.

    PubMed

    Bonhomme-Faivre, L; Mathieu, M C; Depraetere, P; Grossiord, J L; Orbach-Arbouys, S; Puisieux, F; Seiller, M

    1999-02-01

    To tattoo human breast cancer prior to chemotherapy, radiotherapy, or surgery, thus allowing a better localization of the remaining tumor by the surgeon, we developed a formulation containing 10% charcoal suspended in water for parenteral preparations. The present study concerns a new step in the development of the charcoal suspension. We sought to determine whether the addition of various excipients could improve the formulation properties and affect the labeling of tumor by the suspension. We have tested surfactants (egg lecithin, polysorbate 80, Cremophor EL, and Pluronic F68), isotonisants (sugars such as glucose and mannitol), polysaccharides (dextrans 20 and 40), and Cabosil, a pyrogenated silica. Except for glucose and mannitol, which were added at a 5% concentration, the other excipients were added at a 0.1% concentration, they were dissolved in water for parenteral injection and sterilized at 120 degrees C for 20 min. We then measured diffusion in vivo in mammary tumor. In vivo, when injected intratumorally in mice, a greater diffusion of charcoal particles was noted within the tumor (in the case of egg lecithin, polysorbate 80, dextran 20 and 40, and glucose) and sometimes in some organs (e.g., Cremophor EL and mannitol). Pluronic F68 slightly improved the stability of the suspension and did not lead to marked diffusion at the injection site, but it showed slight toxicity and cannot be used in the formulation. We concluded that the best formulation was an aqueous 10% micronized peat charcoal suspension. PMID:10065351

  6. Antagonistic potential of fluorescent pseudomonads and control of charcoal rot of chickpea caused by Macrophomina phaseolina.

    PubMed

    Kumar, Vinod; Kumar, Anuj; Kharwar, R N

    2007-01-01

    The effectiveness of plant growth promoting rhizobacteria especially Pseudomonas fluorescens isolates were tested against charcoal rot of chickpea both in green house as well as in field conditions. Most of the isolates reduced charcoal rot disease and promoted plant growth in green house. A marked increase in shoot and root length was observed in P. fluorescens treated plants. Among all the P. fluorescens isolates Pf4-99, was found most effective in the improvement of chickpea crop in green house as well as in field. Pf4-99 effectively promoted plant growth and produced indole acetic acid in culture medium. This isolate also inhibited the mycelial growth of the M. phaseolina under in vitro conditions and reduced the disease severity Potential isolate (Pf4-99) also significantly increased the biomass of the chickpea plants, shoot length, root length and protein content of the chickpea seeds. A part from these, the total number of seeds per plant and their weight were also enhanced. The colonization of Pf4-99 reduced the incidence of seed mycoflora by which indirectly enhanced the seed germination and vigour index of seedlings. The observations revealed that isolate Pf4-99 is quite effective to reduce the charcoal rot disease both in field and greenhouse, and also increases seed yields significantly Therefore, this isolate appears to be an efficient biocontrol agent against charcoal rot disease as well as yield increasing rhizobacterium. PMID:17717979

  7. Reconstructions of biomass burning from sediment charcoal records to improve data-model comparisons

    NASA Astrophysics Data System (ADS)

    Marlon, J. R.; Kelly, R.; Daniau, A.-L.; Vannière, B.; Power, M. J.; Bartlein, P.; Higuera, P.; Blarquez, O.; Brewer, S.; Brücher, T.; Feurdean, A.; Gil-Romera, G.; Iglesias, V.; Maezumi, S. Y.; Magi, B.; Mustaphi, C. J. C.; Zhihai, T.

    2015-11-01

    The location, timing, spatial extent, and frequency of wildfires are changing rapidly in many parts of the world, producing substantial impacts on ecosystems, people, and potentially climate. Paleofire records based on charcoal accumulation in sediments enable modern changes in biomass burning to be considered in their long-term context. Paleofire records also provide insights into the causes and impacts of past wildfires and emissions when analyzed in conjunction with other paleoenvironmental data and with fire models. Here we present new 1000 year and 22 000 year trends and gridded biomass burning reconstructions based on the Global Charcoal Database version 3, which includes 736 charcoal records (57 more than in version 2). The new gridded reconstructions reveal the spatial patterns underlying the temporal trends in the data, allowing insights into likely controls on biomass burning at regional to global scales. In the most recent few decades, biomass burning has sharply increased in both hemispheres, but especially in the north, where charcoal fluxes are now higher than at any other time during the past 22 000 {years}. We also discuss methodological issues relevant to data-model comparisons, and identify areas for future research. Spatially gridded versions of the global dataset from GCDv3 are provided to facilitate comparison with and validation of global fire simulations.

  8. Charcoal Rot Disease Assessment of Soybean Genotypes and Prelimary Genetic Analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Charcoal rot [Macrophomina phaseolina (Tassi) Goid] of soybean [Glycine max (L.) Merr.] is a disease of economic importance in the United States that causes significant yield losses. In 2002 (30), 2003 (30), 2004 (44) and 2005 (81) a total of 185 soybean genotypes in maturity groups III, IV and V we...

  9. Fungicide, herbicide, and genotype effects on charcoal rot and phomopsis seed decay in soybeans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yield limiting diseases such as charcoal rot and Phomopsis seed decay have significant impact on the economic potential for soybeans because there are few methods for management of these diseases. The objectives of this study were to evaluate application of the herbicide lactofen, the fungicide azo...

  10. Charcoal Rot Disease Assessment of Soybean Genotypes Using a Colony Forming Unit Index

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Charcoal rot [Macrophomina phaseolina (Tassi) Goid] of soybean [Glycine max (L.) Merr.] is a disease of economic significance in the United States and around the world. Yield losses will remain high until resistant genotypes are developed. Progress in developing resistant genotypes is hampered beca...

  11. 4. Photocopied June 1978 R.H. ROBERTSON, PENCIL AND CHARCOAL SKETCH, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Photocopied June 1978 R.H. ROBERTSON, PENCIL AND CHARCOAL SKETCH, LAKE HENDERSON, FROM TAHAWUS CLUB BOAT DOCK. CA. 1914. SOURCE: ARTHUR CROCKER, PRESIDENT OF THE TAHAWUS CLUB. - Adirondack Iron & Steel Company, New Furnace, Hudson River, Tahawus, Essex County, NY

  12. Reconstructions of biomass burning from sediment-charcoal records to improve data-model comparisons

    NASA Astrophysics Data System (ADS)

    Marlon, Jennifer R.; Kelly, Ryan; Daniau, Anne-Laure; Vannière, Boris; Power, Mitchell J.; Bartlein, Patrick; Higuera, Philip; Blarquez, Olivier; Brewer, Simon; Brücher, Tim; Feurdean, Angelica; Gil Romera, Graciela; Iglesias, Virginia; Yoshi Maezumi, S.; Magi, Brian; Mustaphi, Colin J. Courtney; Zhihai, Tonishtan

    2016-06-01

    The location, timing, spatial extent, and frequency of wildfires are changing rapidly in many parts of the world, producing substantial impacts on ecosystems, people, and potentially climate. Paleofire records based on charcoal accumulation in sediments enable modern changes in biomass burning to be considered in their long-term context. Paleofire records also provide insights into the causes and impacts of past wildfires and emissions when analyzed in conjunction with other paleoenvironmental data and with fire models. Here we present new 1000-year and 22 000-year trends and gridded biomass burning reconstructions based on the Global Charcoal Database version 3 (GCDv3), which includes 736 charcoal records (57 more than in version 2). The new gridded reconstructions reveal the spatial patterns underlying the temporal trends in the data, allowing insights into likely controls on biomass burning at regional to global scales. In the most recent few decades, biomass burning has sharply increased in both hemispheres but especially in the north, where charcoal fluxes are now higher than at any other time during the past 22 000 years. We also discuss methodological issues relevant to data-model comparisons and identify areas for future research. Spatially gridded versions of the global data set from GCDv3 are provided to facilitate comparison with and validation of global fire simulations.

  13. An Integrative Suicide Prevention Program for Visitor Charcoal Burning Suicide and Suicide Pact

    ERIC Educational Resources Information Center

    Wong, Paul W. C.; Liu, Patricia M. Y.; Chan, Wincy S. C.; Law, Y. W.; Law, Steven C. K.; Fu, King-Wa; Li, Hana S. H.; Tso, M. K.; Beautrais, Annette L.; Yip, Paul S. F.

    2009-01-01

    An integrative suicide prevention program was implemented to tackle an outbreak of visitor charcoal burning suicides in Cheung Chau, an island in Hong Kong, in 2002. This study evaluated the effectiveness of the program. The numbers of visitor suicides reduced from 37 deaths in the 51 months prior to program implementation to 6 deaths in the 42…

  14. Design and Operating Criteria for Fluorine Disposal by Reaction with Charcoal

    NASA Technical Reports Server (NTRS)

    Schmidt, Harold W.

    1959-01-01

    Experiments with the charcoal-fluorine reaction for the disposal of fluorine have shown generally that this method is effective over a wide range of conditions. Pure fluorine or fluorine diluted with nitrogen to concentrations as low as 0.3 percent fluorine may be disposed of efficiently within the rate limitation. Maximum feed rates have been established and are inversely proportional to the charcoal-bed particle diameter. Moisture content in the charcoal had no appreciable effect on the disposal efficiency after the reaction zone was established and the moisture was driven off by the heat of reaction. There was no evidence of bed poisoning resulting from continued use. Design parameters may be based on the stoichiometric requirements plus sufficient excess charcoal to maintain desired efficiency toward the end of a disposal operation. The length of time a given reactor may be used continuously is limited by the rate of fluorine input and the resistance of the system to heat and fluorine attack. Refractory-lined reactors have been in routine field use at the Lewis Research Center for over a year and have given satisfactory service over a wide range of conditions.

  15. Pyrolysis of blended animal manures to produce combustible gas and value-added charcoal adsorbent

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blended swine solids, chicken litter, and rye grass were pyrolyzed using a skid-mounted sytem. Produced gas composition was analyzed for major hydrocarbons and S-containing compounds. Charcoal was analyzed for its surface functional groups, contact angles, HHV, and total element contents. Some of th...

  16. Seasonal progress of charcoal rot and its impact on soybean productivity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of charcoal rot caused by Macrophomina phaseolina on yield of soybean were evaluated in the field using two genotypes each in maturity groups III and IV. Four separate experiments were established in an area of a field fumigated with methyl bromide. The experiments were: 1) artificiall...

  17. The Charcoal Trap: Miombo Woddlands and the Energy Demands of People

    NASA Astrophysics Data System (ADS)

    Kutsch, W. L.; Merbold, L.; Mukelabai, M. M.

    2012-04-01

    Miombo woodlands cover the transition zone between dry open savannas and moist forests in Southern Africa. They cover about 2.7 million km2 in southern Africa and provide many ecosystem services that support rural life, including medical products, wild foods, construction timber and fuel. In Zambia, as in many of its neighbouring countries, miombo woodlands are currently experiencing accelerating degradation and clearing, mostly with charcoal production as the initial driver. Domestic energy needs in the growing urban areas are largely satisfied by charcoal, which is less energy-efficient fuel on a tree-to-table basis than the firewood that is used in rural areas, but has a higher energy density and is thus cheaper to transport. This study uses data from inventories and from eddy covariance measurements of carbon exchange to characterize the impact of charcoal production on miombo woodlands. We address the following questions: (i) how much carbon is lost at local as well as at national scale and (ii) does forest degradation result in the loss of a carbon sink? On the basis of our data we (iii) estimate the per capita emissions through deforestation and forest degradation in Zambia and relate it to fossil fuel emissions. Furthermore, (iv) a rough estimate of the energy that is provided by charcoal production to private households at a national level is calculated and (v) options for alternative energy supply to private households are discussed.

  18. Fast and Specific Assessment of the Halogenating Peroxidase Activity in Leukocyte-enriched Blood Samples.

    PubMed

    Flemmig, Jörg; Schwarz, Pauline; Bäcker, Ingo; Leichsenring, Anna; Lange, Franziska; Arnhold, Jürgen

    2016-01-01

    In this paper a protocol for the quick and standardized enrichment of leukocytes from small whole blood samples is described. This procedure is based on the hypotonic lysis of erythrocytes and can be applied to human samples as well as to blood of non-human origin. The small initial sample volume of about 50 to 100 µl makes this method applicable to recurrent blood sampling from small laboratory animals. Moreover, leukocyte enrichment is achieved within minutes and with low material efforts regarding chemicals and instrumentation, making this method applicable in multiple laboratory environments. Standardized purification of leukocytes is combined with a highly selective staining method to evaluate halogenating peroxidase activity of the heme peroxidases, myeloperoxidase (MPO) and eosinophil peroxidase (EPO), i.e., the formation of hypochlorous and hypobromous acid (HOCl and HOBr). While MPO is strongly expressed in neutrophils, the most abundant immune cell type in human blood as well as in monocytes, the related enzyme EPO is exclusively expressed in eosinophils. The halogenating activity of these enzymes is addressed by using the almost HOCl- and HOBr-specific dye aminophenyl fluorescein (APF) and the primary peroxidase substrate hydrogen peroxide. Upon subsequent flow cytometry analysis all peroxidase-positive cells (neutrophils, monocytes, eosinophils) are distinguishable and their halogenating peroxidase activity can be quantified. Since APF staining may be combined with the application of cell surface markers, this protocol can be extended to specifically address leukocyte sub-fractions. The method is applicable to detect HOCl and HOBr production both in human and in rodent leukocytes. Given the widely and diversely discussed immunological role of these enzymatic products in chronic inflammatory diseases, this protocol may contribute to a better understanding of the immunological relevance of leukocyte-derived heme peroxidases. PMID:27501318

  19. Wildfire and charcoal enhance nitrification and ammonium-oxidizing bacterial abundance in dry montane forest soils.

    PubMed

    Ball, P N; MacKenzie, M D; DeLuca, T H; Holben, W E

    2010-01-01

    All forest fire events generate some quantity of charcoal, which may persist in soils for hundreds to thousands of years. However, few studies have effectively evaluated the potential for charcoal to influence specific microbial communities or processes. To our knowledge, no studies have specifically addressed the effect of charcoal on ammonia-oxidizing bacteria (AOB) in forest soils. Controlled experiments have shown that charcoal amendment of fire-excluded temperate and boreal coniferous forest soil increases net nitrification, suggesting that charcoal plays a major role in maintaining nitrification for extended periods postfire. In this study, we examined the influence of fire history on gross nitrification, nitrification potential, and the nature and abundance of AOB. Soil cores were collected from sites in the Selway-Bitterroot wilderness area in northern Idaho that had been exposed twice (in 1910, 1934) or three times (1910, 1934, and 1992) in the last 94 yr, allowing us to contrast soils recently exposed to fire to those that experienced no recent fire (control). Charcoal content was determined in the O horizon by hand-separation and in the mineral soil by a chemical digestion procedure. Gross and net nitrification, and potential rates of nitrification were measured in mineral soil. Analysis of the AOB community was conducted using primer sets specific for the ammonia mono-oxygenase gene (amoA) or the 16S rRNA gene of AOB. Denaturing gradient gel electrophoresis was used to analyze the AOB community structure, while AOB abundance was determined by quantitative polymerase chain reaction. Recent (12-yr-old) wildfire resulted in greater charcoal contents and nitrification rates compared with sites without fire for 75 yr, and the more recent fire appeared to have directly influenced AOB abundance and community structure. We predicted and observed greater abundance of AOB in soils recently exposed to fire compared with control soils. Interestingly, sequence data

  20. Characterization and genesis interpretation of charcoal-bearing concretions from the early Eocene Ione Formation, CA

    NASA Astrophysics Data System (ADS)

    Bair, D.; Aburto, F.

    2013-12-01

    Charcoal core concretions have been discovered in the kaolinitic soil horizons of the Ione formation (early Eocene epoch ~52Ma BP). It is thought that the Ione Formation in the Ione Basin was deposited in delta and estuarine waters that were subsequently exhumed and exposed to a warmer, humid, tropical-like environment during the early Eocene. The formation of concretions is indicative of seasonal dryness, and the charcoal cores are evidence of wildfires and of the existence of a forest ecosystem. The mineral outer shells of the concretions have been characterized by powder X-ray diffraction, Electron Microprobe and Laser Ablation Quadruple Mass Spectrometry (LA-ICP-MS). Micro-computed tomography (MCT) scans indicate that these concretions have at least three distinct shells and a inner core with fragments of charcoal without apparent internal organization. The outer shell is mainly composed of a layered mix of kaolinite, quartz, goethite, hematite and birnessite. Some pyrite and jarosite have also been found, which could indicate that goethite may be post-depositional and a product of the bacteria-mediated oxidation of pyrite. The central shell has a similar composition, but with a higher content of iron oxyhydroxides and jarosite. The inner cores of the concretions are mainly composed of a mixture of kaolinite and quartz which correspond to the layer in which the concretions were found. The concretion cores contain loose charcoal fragments in a unsolidified kaolinite matrix. The charcoal fragments have been characterized by Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), C/N isotope analysis, and Synchrotron radiation FTIR (SR-FTIR). Analysis of the ATR-FTIR spectra showed significant absorbance peaks at wavenumbers that coincided with the chemical functionality of other wood biochars. Charcoal from different concretions display (n =12) extremely similar spectra which suggest that they were originated from similar species and

  1. Cellulase activity screening using pure carboxymethylcellulose: application to soluble cellulolytic samples and to plant tissue prints.

    PubMed

    Johnsen, Hanne R; Krause, Kirsten

    2014-01-01

    Reliable, rapid and inexpensive detection of cellulolytic enzymes that can be used for a wide variety of biological and environmental samples are currently in high demand. Here, a new cellulase detection protocol is described that circumvents problems observed with popular agar-based methods by exploiting the ability of carboxymethylcellulose (CMC) to form gel-like surfaces on its own. These pure CMC-layers are sensitive to cellulolytic degradation and stainable by Gram's iodine without showing unwelcome reactions with other enzymes. The staining intensity negatively correlates with the enzyme activity and can be used for quantification. Cellulase activities are not obstructed by high sugar contents (e.g., in plant material) which limit the applicability of other quantification methods, making our new method particularly attractive for screening of plant extracts. A useful variant of this new method is its applicability to plant tissue prints for spatial mapping of the cellulolytic activity in a zymogram-like fashion. PMID:24413752

  2. Antimicrobial activity of different solvent extracted samples from the flowers of medicinally important Plumeria obstusa.

    PubMed

    Ali, Nasir; Ahmad, Dawood; Bakht, Jehan

    2015-01-01

    The present research work was carried out to investigate the antimicrobial (eight bacteria and one fungus) activities of different solvent (ethanol, petroleum ether, chloroform, ethyl acetate and isobutanol) extracted samples from flowers of P. obstusa by disc diffusion method. Analysis of the data revealed that all the five extracts from flowers of P. obstusa showed different ranges of antimicrobial activities. Petroleum ether fractions showed inhibitory activities against all the nine microbial species except Klebsiella pneumonia. Ethyl acetate and isobutanol fractions showed inhibitory effects against all the tested microbial species except Pseudomonas aeruginosa. Chloroform and ethanol extracts had varying levels of inhibitions against all of the tested microorganisms. The most susceptible gram positive bacterium was Bacillus subtilis which was inhibited by all the five extracts while the most resistant gram positive bacterium was Staphylococcus aureus. Erwinia carotovora was the most susceptible gram negative bacterium while Pseudomonas aeruginosa was highly resistant among the gram negative bacteria. PMID:25553696

  3. Sampling artifacts in active air sampling of semivolatile organic contaminants: Comparing theoretical and measured artifacts and evaluating implications for monitoring networks.

    PubMed

    Melymuk, Lisa; Bohlin-Nizzetto, Pernilla; Prokeš, Roman; Kukučka, Petr; Klánová, Jana

    2016-10-01

    The effects of sampling artifacts are often not fully considered in the design of air monitoring with active air samplers. Semivolatile organic contaminants (SVOCs) are particularly vulnerable to a range of sampling artifacts because of their wide range of gas-particle partitioning and degradation rates, and these can lead to erroneous measurements of air concentrations and a lack of comparability between sites with different environmental and sampling conditions. This study used specially adapted filter-sorbent sampling trains in three types of active air samplers to investigate breakthrough of SVOCs, and the possibility of other sampling artifacts. Breakthrough volumes were experimentally determined for a range of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) in sampling volumes from 300 to 10,000 m(3), and sampling durations of 1-7 days. In parallel, breakthrough was estimated based on theoretical sorbent-vapor pressure relationships. The comparison of measured and theoretical determinations of breakthrough demonstrated good agreement between experimental and estimated breakthrough volumes, and showed that theoretical breakthrough estimates should be used when developing air monitoring protocols. Significant breakthrough in active air samplers occurred for compounds with vapor pressure >0.5 Pa at volumes <700 m(3). Sample volumes between 700 and 10,000 m(3) may lead to breakthrough for compounds with vapor pressures between 0.005 and 0.5 Pa. Breakthrough is largely driven by sample volume and compound volatility (therefore indirectly by temperature) and is independent of sampler type. The presence of significant breakthrough at "typical" sampling conditions is relevant for air monitoring networks, and may lead to under-reporting of more volatile SVOCs. PMID:26743995

  4. Dioxin-like activity in environmental and human samples from Greenland and Denmark.

    PubMed

    Long, Manhai; Bonefeld-Jørgensen, Eva C

    2012-11-01

    Dioxins and dioxin-like (DL) compounds are some of the most toxic chemicals being highly persistent in the environment. The toxicological effects of dioxins are mediated via the aryl hydrocarbon receptor (AhR). Compounds of diverse structure and lipophility can bind and activate AhR. The AhR transactivation bioassay is utilized in an array of projects to study the AhR-mediated activities of individual chemicals and mixtures and for epidemiological purposes. This review summarizes a series of studies regarding the DL-activity of single compounds and complex compound mixtures in the environment and humans. We found that some pesticides, plasticizers and phytoestrogens can activate the AhR, and the combined effect of compounds with no or weak AhR potency cannot be ignored. The significant DL-activity in the wastewater effluent indicates the treatment is not sufficient to prevent contamination of surface waters with dioxins. Our results from human studies suggest that the serum DL-activity reflect the complex mixture of persistent organic pollutants (POPs). Greenlandic Inuit had lower serum DL-activity level compared to Europeans, probably due to long distance from the dioxin sources and UV degradation of the high potent dioxin and/or the inhibitory effect of the high level of non-DL POPs. Selective bioaccumulation of PCBs in the food chain may contribute to the negative correlation between serum POPs and DL-activity observed in Greenlandic Inuit. Hence the AhR transactivation bioassay provides a cost-effective and integrated screening tool for measurement of the DL-activity in human, environmental and commercial samples. PMID:22858370

  5. Chemical and Isotopic Thresholds in Charring: Implications for the Interpretation of Charcoal Mass and Isotopic Data

    NASA Astrophysics Data System (ADS)

    Pyle, L.; Hockaday, W. C.; Boutton, T. W.; Zygourakis, K.; Kinney, T.; Masiello, C. A.

    2014-12-01

    Charcoal plays a significant role in the long-term carbon cycle and its use as a soil amendment is becoming a viable carbon sequestration strategy (biochar). One challenge in this research area has been comparing results between studies in part due to the diversity of lab and field production conditions. Although the highest treatment temperature (HTT) is often used to describe pyrolysis conditions, several studies have shown that length of time at the highest temperature can also cause changes to the physicochemical qualities of charcoal and ignoring this effect may introduce inter-comparison problems. Addressing this issue becomes especially important in the discussion of optimizing biochar for soil remediation and carbon sequestration, and in discussions of charcoal use in reconstructing past fire regimes, as increasing time at temperature may cause changes in charcoal properties similar to the changes caused by increasing HTT. Here we introduce a formal definition of charring intensity (CI) to more accurately characterize pyrolysis, and we document variation in this property with pyrolysis temperature and reaction duration. We found two types of responses to CI: either a linear or a threshold relationship. We show that a threshold exists where %C, %N and δ15N begin exhibiting large changes, and this CI threshold co-occurred with an increase in charcoal aromaticity. Mass yield decreased linearly with charring intensity and carbon isotopes did not change from original biomass values in our controlled laboratory experiments. Analysis of these data shows that pyrolysis parameters should be defined in the literature as a combination of temperature and duration conditions, and that biomass that has undergone pyrolysis may be influencing soil organic nitrogen. Additionally, the lack of alteration in carbon isotopes across our matrix supports the efficacy of using pyrolyzed material for archaeological reconstructions.

  6. The Preparation and Reduction Behavior of Charcoal Composite Iron Oxide Pellets

    NASA Astrophysics Data System (ADS)

    Konishi, Hirokazu; Usui, Tateo; Harada, Takeshi

    In the energy conversion, biomass has novel advantage, i.e., no CO2 emission, because of carbon neutral. Charcoal composite iron oxide pellets were proposed to decrease CO2 emission for the ironmaking. These pellets were promising to decrease the initial temperature for reduction reaction of carbon composite iron ore agglomerate under a rising temperature condition, such as in a blast furnace shaft. In order to obtain charcoal, Japanese cedar and cypress were carbonized from room temperature to maximum carbonization temperature (TC, max = 1273 K) at a heating rate of 200 K/h, and kept at TC, max until arrival time of 6 h. Reducing gases of CO and CH4 started releasing from relatively low temperature (500 K). In the total gas volume of carbonization, H2 gas of Japanese cedar was more than that of Japanese cypress. These woods have more CO gas volume than Newcastle blend coal has. The obtained charcoal was mixed with reagent grade hematite in the mass ratio of one to four. Then, a small amount of Bentonite was added to the mixture as a binder, and the charcoal composite iron oxide pellets were prepared and reduced at 1273, 1373 and 1473 K in nitrogen gas atmosphere. It was conirmed by the generated gas analysis during reduction reaction that charcoal composite iron oxide pellets had higher reducibility than char composite pellets using Newcastle blend coal. From the XRD analysis of the reduced pellets, it was found that the original Fe2O3 was almost reduced to Fe for 60 min at 1273 K, 20 min at 1373 K and 5~15 min at 1473 K.

  7. Combining charcoal sediment and molecular markers to infer a Holocene fire history in the Maya lowlands of Petén, Guatemala

    NASA Astrophysics Data System (ADS)

    Kirchgeorg, Torben; Schüpbach, Simon; Colombaroli, Daniele; Beffa, Giorgia; Radaelli, Marta; Kehrwald, Natalie; Barbante, Carlo

    2015-04-01

    Holocene vegetation changes in the Maya Lowlands during the Holocene are a result of changing climate conditions, solely anthropogenic activities, or interactions of both factors. As a consequence, it is difficult to assess how tropical ecosystems will cope with projected changes in precipitation and land-use intensification over the next decades. We investigated the role of fire during the Holocene by combining different proxies. We distinguished between three different morphotypes (grass, wood and leaves) in macroscopic charcoal. We also determined the molecular fire proxies levoglucosan, mannosan and galactosan. Combining these different fire proxies allows a more robust understanding of the complex history of fire regimes at different spatial scales during the Holocene. Comparing the two biomass burning proxies may help increase our understanding about advantages and limitations of molecular markers as proxies for past fire reconstruction in lake sediments. In order to infer changes in past biomass burning, we analysed a lake sediment core from Lake Petén Itzá, Guatemala (17°00'N, 89°50'W, 110 m above sea level), and compared our results with millennial-scale vegetation and climate change data available in this area. Some differences were observed between the two records and we assumed that while macroscopic charcoal represents a local fire signal, the molecular fire proxies records seem to be influenced by regional to supra-regional fire or low temperature fires. During the Holocene we detected three periods of high fire activity: 9500-6000 cal yr BP, 3800 cal yr BP and 2700 cal yr BP. We attributed the first maximum (9500-6000 cal yr BP) to only climate conditions, which corresponds with observations from previous studies in this region. The fast decrease in the relative abundance of woody charcoal to grass charcoal at the 3800 cal yr BP fire maximum may result from human activity, but we cannot exclude that this shift was related to climate conditions

  8. Quantitative conformationally sampled pharmacophore for delta opioid ligands: reevaluation of hydrophobic moieties essential for biological activity.

    PubMed

    Bernard, Denzil; Coop, Andrew; MacKerell, Alexander D

    2007-04-19

    Recent studies have indicated several therapeutic applications for delta opioid agonists and antagonists. To exploit the therapeutic potential of delta opioids developing a structural basis for the activity of ligands at the delta opioid receptor is essential. The conformationally sampled pharmacophore (CSP) method (Bernard et al. J. Am. Chem. Soc. 2003, 125, 3103-3107) is extended here to obtain quantitative models of delta opioid ligand efficacy and affinity. Quantification is performed via overlap integrals of the conformational space sampled by ligands with respect to a reference compound. Iterative refinement of the CSP model identified hydrophobic groups other than the traditional phenylalanine residues as important for efficacy and affinity in DSLET and ICI 174 864. The obtained models for a structurally diverse set of peptidic and nonpeptidic delta opioid ligands offer good predictions with R2 values>0.9, and the predicted efficacy for a set of test compounds was consistent with the experimental values. PMID:17367120

  9. Microwave acid digestion and preconcentration neutron activation analysis of biological and diet samples for iodine.

    PubMed

    Rao, R R; Chatt, A

    1991-07-01

    A simple preconcentration neutron activation analysis (PNAA) method has been developed for the determination of low levels of iodine in biological and nutritional materials. The method involves dissolution of the samples by microwave digestion in the presence of acids in closed Teflon bombs and preconcentration of total iodine, after reduction to iodide with hydrazine sulfate, by coprecipitation with bismuth sulfide. The effects of different factors such as acidity, time for complete precipitation, and concentrations of bismuth, sulfide, and diverse ions on the quantitative recovery of iodide have been studied. The absolute detection limit of the PNAA method is 5 ng of iodine. Precision of measurement, expressed in terms of relative standard deviation, is about 5% at 100 ppb and 10% at 20 ppb levels of iodine. The PNAA method has been applied to several biological reference materials and total diet samples. PMID:1897721

  10. The nature and origin of Narrow Line AGN activity in a sample of isolated SDSS galaxies

    NASA Astrophysics Data System (ADS)

    Coziol, R.; Torres-Papaqui, J. P.; Plauchu-Frayn, I.; Islas-Islas, J. M.; Ortega-Minakata, R. A.; Neri-Larios, D. M.; Andernach, H.

    2011-10-01

    We discuss the nature and origin of the nuclear activity observed in a sample of 292 SDSS narrow-emission-line galaxies, considered to have formed and evolved in isolation. The fraction of Narrow Line AGNs (NLAGNs) and Transition type Objects (TOs; a NLAGN with circumnuclear star formation) amounts to 64% of the galaxies. We verify that the probability for a galaxy to show an AGN characteristic increases with the bulge mass of the galaxy (Torres-Papaqui et al. 2011), and find evidence that this trend is really a by-product of the morphology, suggesting that the AGN phenomenon is intimately connected with the formation process of the galaxies. The NLAGNs in our sample are consistent with a scaled-down or powered-down versions of quasars and Broad Line AGNs.

  11. Improving Polymerase Activity with Unnatural Substrates by Sampling Mutations in Homologous Protein Architectures.

    PubMed

    Dunn, Matthew R; Otto, Carine; Fenton, Kathryn E; Chaput, John C

    2016-05-20

    The ability to synthesize and propagate genetic information encoded in the framework of xeno-nucleic acid (XNA) polymers would inform a wide range of topics from the origins of life to synthetic biology. While directed evolution has produced examples of engineered polymerases that can accept XNA substrates, these enzymes function with reduced activity relative to their natural counterparts. Here, we describe a biochemical strategy that enables the discovery of engineered polymerases with improved activity for a given unnatural polymerase function. Our approach involves identifying specificity determining residues (SDRs) that control polymerase activity, screening mutations at SDR positions in a model polymerase scaffold, and assaying key gain-of-function mutations in orthologous protein architectures. By transferring beneficial mutations between homologous protein structures, we show that new polymerases can be identified that function with superior activity relative to their starting donor scaffold. This concept, which we call scaffold sampling, was used to generate engineered DNA polymerases that can faithfully synthesize RNA and TNA (threose nucleic acid), respectively, on a DNA template with high primer-extension efficiency and low template sequence bias. We suggest that the ability to combine phenotypes from different donor and recipient scaffolds provides a new paradigm in polymerase engineering where natural structural diversity can be used to refine the catalytic activity of synthetic enzymes. PMID:26860781

  12. The determination of uranium in food samples by Compton suppression epithermal neutron activation analysis.

    PubMed

    Kapsimalis, R; Landsberger, S; Ahmed, Y A

    2009-12-01

    Eight foods common to the Nigerian diet were analyzed for trace amounts of uranium using epithermal neutron activation analysis. Food sample sizes of roughly one-half gram, irradiated for 10 min, with a 15 min decay time and counting time for 10 min yielded detection limits between 0.02 and 0.04 Bq/kg. Dried milk, chicken pasta, spaghetti and biscuits had less than detectable amounts of uranium, while sorghum, wheat and brown beans contained 0.73, 0.23 and 0.16 Bq/kg, respectively. PMID:19541492

  13. A low-luminosity type-1 QSO sample. III. Optical spectroscopic properties and activity classification

    NASA Astrophysics Data System (ADS)

    Tremou, E.; Garcia-Marin, M.; Zuther, J.; Eckart, A.; Valencia-Schneider, M.; Vitale, M.; Shan, C.

    2015-08-01

    Context. We report on the optical spectroscopic analysis of a sample of 99 low-luminosity quasi-stellar objects (LLQSOs) at z ≤ 0.06 base the Hamburg/ESO QSO Survey (HES). To better relate the low-redshift active galactic nucleus (AGN) to the QSO population it is important to study samples of the latter type at a level of detail similar to that of the low-redshift AGN. Powerful QSOs, however, are absent at low redshifts due to evolutionary effects and their small space density. Our understanding of the (distant) QSO population is, therefore, significantly limited by angular resolution and sensitivity. The LLQSOs presented here offer the possibility of studying the faint end of this population at smaller cosmological distances and, therefore, in greater detail. Aims: In comparing two spectroscopic methods, we aim to establish a reliable activity classification scheme of the LLQSOs sample. Our goal is to enrich our systematic multiwavelength analysis of the AGN/starburst relation in these systems and give a complementary information on this particular sample of LLQSOs from the Hamburg ESO survey. Methods: Here, we present results of the analysis of visible wavelength spectroscopy provided by the HES and the 6 Degree Field Galaxy Survey (6dFGS). These surveys use different spectroscopic techniques, long-slit and circular fiber, respectively. These allow us to assess the influence of different apertures on the activity of the LLQSOs using classical optical diagnostic diagrams. We perform a Gaussian fitting of strong optical emission lines and decompose narrow and broad Balmer components. Results: A small number of our LLQSO present no broad component, which is likely to be present but buried in the noise. Two sources show double broad components, whereas six comply with the classic NLS1 requiremnts. As expected in NLR of broad line AGNs, the [Sii]-based electron density values range between 100 and 1000 Ne/cm3. Using the optical characteristics of Populations A and B

  14. Development of needle trap technology for on-site determinations: active and passive sampling.

    PubMed

    Asl-Hariri, Saba; Gómez-Ríos, German A; Gionfriddo, Emanuela; Dawes, Peter; Pawliszyn, Janusz

    2014-06-17

    This study presents a thorough evaluation of new prototypes of extended tip needle trap devices (NT), as well as their application to in situ sampling of biological emissions and active/passive on-site sampling of indoor air. A new NT prototype was constructed with a side hole above the sorbent and an extended tip that fits inside the restriction of the narrow neck liner to increase desorption efficiency. New prototype needles were initially packed with divinylbenzene particles at SGE Analytical Science for the purpose of studying biogenic emissions of pine trees. Prior to their final application, they were evaluated in terms of robustness after multiple use (n > 10), as well as amount extracted of volatile organic compounds (VOCs). An ANOVA test for all the probes showed that at a 95% level of confidence, there were not statistical differences observed among the 9 NTs tested. In addition, the needles were also packed in laboratory with synthesized highly cross-linked PDMS as a frit to immobilize carboxen (Car) particles for spot sampling. For passive sampling, the needles were packed with Car particles embedded in PDMS to simplify calculations in passive mode. The use of NTs as spot samplers, as well as a passive sampler under controlled conditions in the laboratoryyielded a relative standard deviation of less than 15%. Finally, a new, reusable and readily deployable penlike diffusive sampler for needle traps (PDS-NT) was built and tested. Application of the PDS-NT in combination with NT-spot sampling toward the analysis of indoor air in a polymer synthesis laboratory showed good agreement between both techniques for the analyte studied, yielding averages of 0.03 and 0.025 ng/mL of toluene, respectively. PMID:24842217

  15. The Relationship between Active Coping and Trait Resilience across U.S. and Taiwanese College Student Samples

    ERIC Educational Resources Information Center

    Li, Ming-Hui; Nishikawa, Takeshi

    2012-01-01

    This study compared predictors of active coping (people's tendency to actively cope with stress) among college students in the United States and Taiwan. In both samples, trait resilience predicted active coping and mediated the effect of self-efficacy on active coping. The findings indicate that trait resilience influences college students' active…

  16. Joint Associations of Residential Density and Neighborhood Involvement with Physical Activity among a Multiethnic Sample of Urban Adults

    ERIC Educational Resources Information Center

    Johnson-Lawrence, Vicki; Schulz, Amy J.; Zenk, Shannon N.; Israel, Barbara A.; Wineman, Jean; Marans, Robert W.; Rowe, Zachary

    2015-01-01

    Regular physical activity is associated with improvements in overall health. Although resident involvement in neighborhood social activities is positively associated with physical activity, neighborhood design features, including residential density, have varied associations with physical activity. Using data from a multiethnic sample of 696…

  17. Utilization of unpeeled cassava (Manihot esculenta Crantz) root meal supplemented with or without charcoal by broiler chickens.

    PubMed

    Oso, A O; Akapo, O; Sanwo, K A; Bamgbose, A M

    2014-06-01

    A 42-day feeding trial was conducted using 480-day-old, male Marshall broilers to study the utilization of unpeeled cassava root meal (UCRM) supplemented with or without 6 g/kg charcoal. The experimental design was laid out in a 3 × 2 factorial arrangement of treatments having three inclusion levels of UCRM (0, 100 and 200 g/kg) with or without 6 g/kg charcoal supplementation. Each treatment consisted of 80 birds replicated eight times with 10 birds per replicate. Main effect of inclusion level of UCRM and supplementation of charcoal showed reduced (p < 0.05) final live weight, weight gain, feed intake and apparent crude protein digestibility of the birds with increasing inclusion levels of UCRM. Birds fed diets supplemented with charcoal showed higher (p < 0.05) final live weight, weight gain and feed intake than birds fed diets without charcoal. Supplementation of charcoal in diet containing 100 g/kg UCRM resulted in improved (p < 0.05) weight gain when compared with birds fed similar diet but not supplemented with charcoal. Broilers fed diet containing no UCRM but supplemented with charcoal had the highest overall (p < 0.05) final live weight and weight gain, while birds fed diet containing 200 g/kg UCRM supplemented with charcoal recorded the poorest (p < 0.05) final live weight and weight gain. Serum glutamate oxaloacetate transaminase (SGOT) and serum thiocyanate concentration increased (p < 0.05) with increasing dietary inclusion levels of UCRM. Dietary supplementation of charcoal resulted in increased (p < 0.05) concentration of serum glucose and cholesterol and reduced (p < 0.05) SGOT concentration. Birds fed diets containing UCRM had high (p < 0.05) serum thiocyanate concentration irrespective of dietary supplementation or not with 6 g/kg charcoal. In conclusion, supplementation of diet containing up to 100 g/kg UCRM with 6 g/kg charcoal showed improved weight gain without any deleterious effect on serum metabolites. PMID:23721067

  18. Macro-Particle Charcoal C Content following Prescribed Burning in a Mixed-Conifer Forest, Sierra Nevada, California

    PubMed Central

    Wiechmann, Morgan L.; Hurteau, Matthew D.; Kaye, Jason P.; Miesel, Jessica R.

    2015-01-01

    Fire suppression and changing climate have resulted in increased large wildfire frequency and severity in the western United States, causing carbon cycle impacts. Forest thinning and prescribed burning reduce high-severity fire risk, but require removal of biomass and emissions of carbon from burning. During each fire a fraction of the burning vegetation and soil organic matter is converted into charcoal, a relatively stable carbon form. We sought to quantify the effects of pre-fire fuel load and type on charcoal carbon produced by biomass combusted in a prescribed burn under different thinning treatments and to identify more easily measured predictors of charcoal carbon mass in a historically frequent-fire mixed-conifer forest. We hypothesized that charcoal carbon produced from coarse woody debris (CWD) during prescribed burning would be greater than that produced from fine woody debris (FWD). We visually quantified post-treatment charcoal carbon content in the O-horizon and the A-horizon beneath CWD (> 30 cm diameter) and up to 60 cm from CWD that was present prior to treatment. We found no difference in the size of charcoal carbon pools from CWD (treatment means ranged from 0.3–2.0 g m-2 of A-horizon and 0.0–1.7 g m-2 of O-horizon charcoal) and FWD (treatment means ranged from 0.2–1.7 g m-2 of A-horizon and 0.0–1.5 g m-2 of O-horizon charcoal). We also compared treatments and found that the burn-only, understory-thin and burn, and overstory-thin and burn treatments had significantly more charcoal carbon than the control. Charcoal carbon represented 0.29% of total ecosystem carbon. We found that char mass on CWD was an important predictor of charcoal carbon mass, but only explained 18–35% of the variation. Our results help improve our understanding of the effects forest restoration treatments have on ecosystem carbon by providing additional information about charcoal carbon content. PMID:26258533

  19. Macro-particle charcoal C content following prescribed burning in a mixed-conifer forest, Sierra Nevada, California.

    PubMed

    Wiechmann, Morgan L; Hurteau, Matthew D; Kaye, Jason P; Miesel, Jessica R

    2015-01-01

    Fire suppression and changing climate have resulted in increased large wildfire frequency and severity in the western United States, causing carbon cycle impacts. Forest thinning and prescribed burning reduce high-severity fire risk, but require removal of biomass and emissions of carbon from burning. During each fire a fraction of the burning vegetation and soil organic matter is converted into charcoal, a relatively stable carbon form. We sought to quantify the effects of pre-fire fuel load and type on charcoal carbon produced by biomass combusted in a prescribed burn under different thinning treatments and to identify more easily measured predictors of charcoal carbon mass in a historically frequent-fire mixed-conifer forest. We hypothesized that charcoal carbon produced from coarse woody debris (CWD) during prescribed burning would be greater than that produced from fine woody debris (FWD). We visually quantified post-treatment charcoal carbon content in the O-horizon and the A-horizon beneath CWD (> 30 cm diameter) and up to 60 cm from CWD that was present prior to treatment. We found no difference in the size of charcoal carbon pools from CWD (treatment means ranged from 0.3-2.0 g m-2 of A-horizon and 0.0-1.7 g m-2 of O-horizon charcoal) and FWD (treatment means ranged from 0.2-1.7 g m-2 of A-horizon and 0.0-1.5 g m-2 of O-horizon charcoal). We also compared treatments and found that the burn-only, understory-thin and burn, and overstory-thin and burn treatments had significantly more charcoal carbon than the control. Charcoal carbon represented 0.29% of total ecosystem carbon. We found that char mass on CWD was an important predictor of charcoal carbon mass, but only explained 18-35% of the variation. Our results help improve our understanding of the effects forest restoration treatments have on ecosystem carbon by providing additional information about charcoal carbon content. PMID:26258533

  20. Study of activation data of metal samples from LDEF-1 and Spacelab-2

    NASA Technical Reports Server (NTRS)

    Laird, C. E.

    1994-01-01

    Gamma-ray spectra obtained from samples flown aboard the Long Duration Exposure Facility have been analyzed to obtain the nuclear species produced in this material by the interaction of this material with protons and neutrons in this material by the interaction of this material with protons and neutrons encountered in its 69 month orbital flight as well as to quantify the specific activity (pCi/kg) of these nuclear species. This quantification requires accurate corrections of efficiency, self-attenuation, and background. Plans have been developed for archival of the spectra in a form readily accessible to the scientific, engineering and technical community engaged in space research and application. Work has been initiated in the process of estimating the flux of activating particles encountered by material at various locations of the spacecraft.

  1. The influence of production conditions, starting material and deposition environment on charcoal alteration in a tropical biome.

    NASA Astrophysics Data System (ADS)

    Ascough, Philippa; Bird, Michael; Meredith, Will; Large, David; Snape, Colin; Manion, Corinne

    2014-05-01

    Natural and anthropogenic burning events are a key link in the global carbon cycle, substantially influencing atmospheric CO2 levels, and consuming c.8700 teragrams yr-1 of dry biomass [1,2,3]. An important result of this process is charcoal, when lignocellulosic structures in biomass (e.g. wood) are converted to aromatic domains with high chemical stability. Charcoal is therefore not readily re-oxidized to CO2, with estimates of 5-7 ky for the half-life of charcoal carbon in soils [3,4]. Charcoal's high carbon content coupled with high environmental resistance has led to the concept of biochar as a valuable means of global carbon sequestration, capable of carbon offsets comparable to annual anthropogenic fuel emissions [5,6,7]. Charcoal is not, however, an environmentally inert substance, and at least some components of charcoal are susceptible to alteration in depositional environments. Despite the importance of charcoal in global carbon cycling, the mechanisms by which charcoal is altered in the environment remain, as yet, poorly understood. This fact limits our ability to properly incorporate both natural environmental charcoal and biochar into global carbon budgets. This study aimed to improve understanding of charcoal alteration in the environment by examining the influence of production conditions, starting material and deposition environment on the physical and chemical characteristics of charcoal at a field site in the Daintree rainforest. These factors have been identified as critical in determining the dynamics of charcoal in depositional environments [8,9] and climatic conditions at the field site (in Tropical Queensland, Australia) are likely to result in extensive alteration of charcoal. Charcoal from wood (Nothofagus spp.), algae (Enteromorpha spp.), and sugarcane (Saccharum spp.) biomass was produced at temperatures over 300-500°C and exposed to conditions of varying pH and vegetation cover. The effect of these variables on charcoal chemistry

  2. Hard-X-ray spectra of active galactic nuclei in the INTEGRAL complete sample

    NASA Astrophysics Data System (ADS)

    Molina, M.; Bassani, L.; Malizia, A.; Stephen, J. B.; Bird, A. J.; Bazzano, A.; Ubertini, P.

    2013-08-01

    In this paper, we present the hard-X-ray spectral analysis of a complete sample of active galactic nuclei (AGNs) detected by INTEGRAL/IBIS. In conjunction with IBIS spectra, we make use of Swift/BAT data, with the aim of cross-calibrating the two instruments, studying source variability and constraining some important spectral parameters. We find that flux variability is present in at least 14 per cent of the sample, while spectral variability is found only in one object. There is general good agreement between BAT and IBIS spectra, despite a systematic mismatch of about 22 per cent in normalization. When fitted with a simple power-law model, type 1 and type 2 sources appear to have very similar average photon indices, suggesting that they are powered by the same mechanism. As expected, we also find that a simple power law does not always describe the data sufficiently well, thus indicating a certain degree of spectral complexity, which can be ascribed to features like a high energy cut-off and/or a reflection component. Fixing the reflection to be 0, 1 or 2, we find that our sample covers quite a large range in photon indices as well as cut-off energies; however, the spread is due only to a small number of objects, while the majority of the AGNs lie within well-defined boundaries of photon index (1 ≤ Γ ≤ 2) and cut-off energy (30 ≤ Ecut ≤ 300 keV).

  3. Magnetic Measurements of Bacterial Activity in Mid Oceanic Ridge Basalt Samples.

    NASA Astrophysics Data System (ADS)

    Carlut, J.; Horen, H.; Brunet, F.; Janots, D.; Pozzi, J.

    2004-12-01

    Magnetic properties of the young oceanic crust gives insights on the 3D structure at ridges axis and on variations of the Earth's magnetic field. Accurate interpretations depend on our understanding of the magnetic stability of titanomagnetite crystals carrying the magnetic signal. The mean remanent intensity of young ocean basalts shows significant variations with age and it has been suggested that rapid chemical alteration of titanomagnetite could be responsible. Ubiquitous presence of bacteria in deep marine environment and their ability to interact with iron oxides suggest a possible important impact of these life forms on the stability of titanomagnetites. In vivo experiments have been conducted on more than 15 fresh lava macro samples with a batch of selected sulfate reducing bacteria of the desulfovibrio genus, relevant to the deep biosphere. Remanent magnetization of samples was measured at regular time interval, in addition to more complete magnetic and chemical characterization at beginning and end of experiments. After a few months results show a significant contribution of bacterial activity on magnetic properties of samples, in particular a well defined drop in remanence. Our results suggest a strong impact of bacteria on the alteration rate of iron oxides carrying the magnetic signal within the oceanic crust.

  4. X-ray spectral parameters for a sample of 95 active galactic nuclei

    NASA Astrophysics Data System (ADS)

    Vasylenko, A. A.; Zhdanov, V. I.; Fedorova, E. V.

    2015-12-01

    We present a broadband X-ray analysis of a new homogeneous sample of 95 active galactic nuclei (AGN) from the 22-month Swift/BAT all-sky survey. For this sample we treated jointly the X-ray spectra observed by XMM-Newton and INTEGRAL missions for the total spectral range of 0.5-250 keV. Photon index \\varGamma, relative reflection R, equivalent width of Fe K_{α} line EW_{FeK}, hydrogen column density NH, exponential cut-off energy Ec and intrinsic luminosity L_{corr} are determined for all objects of the sample. We investigated correlations \\varGamma-R, EW_{FeK}-L_{corr}, \\varGamma-Ec, EW_{FeK}-NH. Dependence "\\varGamma-R" for Seyfert 1/2 galaxies has been investigated separately. We found that the relative reflection parameter at low power-law indexes for Seyfert 2 galaxies is systematically higher than for Seyfert 1 ones. This can be related to an increasing contribution of the reflected radiation from the gas-dust torus. Our data show that there exists some anticorrelation between EW_{FeK} and L_{corr}, but it is not strong. We have not found statistically significant deviations from the AGN Unified Model.

  5. Magnetic Monitoring and Characterization at the Nanoscale of Bacterial Activity in Mid Oceanic Ridge Basalt Samples

    NASA Astrophysics Data System (ADS)

    Carlut, J.; Benzerara, K.; Horen, H.; Baronnet, A.

    2011-12-01

    Microbial communities have been shown over the last few years to be a significant component of the sub-sea floor crustal environment. The ubiquitous presence of these life forms suggests an important chemical impact on the host rocks. Among the diverse species, sulfate-reducing bacteria have been suggested, based on sulfur isotope studies, to be a major actor of the oceanic rocks alteration. Laboratory experiments were thus conducted on basalts from the East Pacific Ridge incubated with model sulfate-reducing bacteria. Results show that such bacteria can have a strong impact on the alteration rate of iron oxides carrying the magnetic signal of oceanic rocks. To some extent microbial processes can thus play a role in the decrease of sea floor magnetic signal. Such findings also open ways for the remote monitoring of bacterial activity through magnetic measurements. In order to gain insights on the mechanisms involved we characterized alteration features of iron oxides at the nanoscale in laboratory bio-altered samples and natural samples. We used a combination of scanning electron microscope, focused ion beam milling, ion beam thinning, transmission electron microscopy and scanning transmission X-ray microscopy. Some of the iron oxide crystals from these samples show singular alteration rims mostly composed of Fe and S and measuring a few nanometers in thickness. These observations contribute to understand the potential role of microbes in the alteration of the oceanic crust and possible impact on the magnetic signal.

  6. Broad Hβ Emission-line Variability in a Sample of 102 Local Active Galaxies

    NASA Astrophysics Data System (ADS)

    Runco, Jordan N.; Cosens, Maren; Bennert, Vardha N.; Scott, Bryan; Komossa, S.; Malkan, Matthew A.; Lazarova, Mariana S.; Auger, Matthew W.; Treu, Tommaso; Park, Daeseong

    2016-04-01

    A sample of 102 local (0.02 ≤ z ≤ 0.1) Seyfert galaxies with black hole masses MBH > 107M⊙ was selected from the Sloan Digital Sky Survey (SDSS) and observed using the Keck 10 m telescope to study the scaling relations between MBH and host galaxy properties. We study profile changes of the broad Hβ emission line within the three to nine year time frame between the two sets of spectra. The variability of the broad Hβ emission line is of particular interest, not only because it is used to estimate MBH, but also because its strength and width are used to classify Seyfert galaxies into different types. At least some form of broad-line variability (in either width or flux) is observed in the majority (∼66%) of the objects, resulting in a Seyfert-type change for ∼38% of the objects, likely driven by variable accretion and/or obscuration. The broad Hβ line virtually disappears in 3/102 (∼3%) extreme cases. We discuss potential causes for these changing look active galactic nuclei. While similar dramatic transitions have previously been reported in the literature, either on a case-by-case basis or in larger samples focusing on quasars at higher redshifts, our study provides statistical information on the frequency of Hβ line variability in a sample of low-redshift Seyfert galaxies.

  7. Determination of radium-226 in environmental and personal monitoring samples.

    PubMed

    Lawrie, W C; Desmond, J A; Spence, D; Anderson, S; Edmondson, C

    2000-01-01

    Radium-226 is a member of the Uranium-238 natural decay series and is the most hazardous radionuclide released to the environment from uranium mining and milling. Due to its long half-life (1600 years) and radiological effects it is one of the most important isotopes to be determined among the naturally occurring nuclides in environmental samples. It is also among the most toxic long-lived alpha-emitters present in environmental samples, as well as one of the most widespread. The requirement for the determination of radium has become a matter of interest in public health due to its hazardous nature with respect to internal exposure. It is concentrated in bones, thus increasing the internal radiation dose of individuals. The methodology developed involves dissolving solid samples by microwave digestion. The radium is then separated from matrix interferents by cation exchange chromatography and subsequently electrodeposited onto a stainless steel disc. Alpha-Spectrometry is employed to determine the activity in the sample. A limit of detection of 20 mBq l(-1) for ground water samples (100 ml) and 20 mBq g(-1) for solid samples (0.1 g) is achievable. The method has been validated via an intercomparison exercise and analysis of a marine sediment reference material. Samples analysed include run off waters from uranium mines, coal and fly ash and also trapping media such as silica gel, charcoal and activated carbon. PMID:10879851

  8. Activity ratios of 137Cs, 90Sr and 239+240Pu in environmental samples.

    PubMed

    Bossew, P; Lettner, H; Hubmer, A; Erlinger, C; Gastberger, M

    2007-01-01

    Both global and Chernobyl fallout have resulted in environmental contamination with radionuclides such as 137Cs, 90Sr and 239+240Pu. In environmental samples, 137Cs and 239+240Pu can be divided into the contributions of either source, if also the isotopes 134Cs and 238Pu are measurable, based on the known isotopic ratios in global and Chernobyl fallout. No analogous method is available for 90Sr. The activity ratios of Sr to Cs and Pu, respectively, are known for the actual fallout mainly from air filter measurements; but due to the high mobility of Sr in the environment, compared to Cs and Pu, these ratios generally do not hold for the inventory many years after deposition. In this paper we suggest a method to identify the mean contributions of global and Chernobyl fallout to total Sr in soil, sediment and cryoconite samples from Alpine and pre-Alpine regions of Austria, based on a statistical evaluation of Sr/Cs/Pu radionuclide activity ratios. Results are given for Sr:Cs, Sr:Pu and Cs:Pu ratios. Comparison with fallout data shows a strong depletion of Sr against Cs and Pu. PMID:17407799

  9. Neutron activation determination of iridium, gold, platinum, and silver in geologic samples

    USGS Publications Warehouse

    Millard, H.T., Jr.

    1987-01-01

    Low-level methods for the determination of iridium and other noble metals have become increasingly important in recent years due to interest in locating abundance anomalies associated with the Cretaceous and Tertiary (K-T) boundary. Typical iridium anomalies are in the range of 1 to 100 ??g/kg (ppb). Thus methods with detection limits near 0.1 ??g/kg should be adequate to detect K-T boundary anomalies. Radiochemical neutron activation analysis methods continue to be required although instrumental neutron activation analysis techniques employing elaborate gamma-counters are under development. In the procedure developed in this study samples irradiated in the epithermal neutron facility of the U. S. Geological Survey TRIGA Reactor (Denver, Colorado) are treated with a mini-fire assay technique. The iridium, gold, and silver are collected in a 1-gram metallic lead button. Primary contaminants at this stage are arsenic and antimony. These can be removed by heating the button with a mixture of sodium perioxide and sodium hydroxide. The resulting 0.2-gram lead bead is counted in a Compton suppression spectrometer. Carrier yields are determined by reirradiation of the lead beads. This procedure has been applied to the U.S.G.S. Standard Rock PCC-1 and samples from K-T boundary sites in the Western Interior of North America. ?? 1987 Akade??miai Kiado??.

  10. Design of a californium source-driven measurement system for accountability of material recovered from the Molten Salt Reactor Experiment charcoal bed

    SciTech Connect

    Bentzinger, D.L.; Perez, R.B.; Mattingly, J.K.; Valentine, T.E.; Mihalczo, J.T.

    1998-05-01

    The Molten Salt Reactor Experiment Facility (MSRE) operated from 1965 to 1969. The fuel was a molten salt that flowed through the reactor core which consisted of uranium tetrafluoride with molten lithium and beryllium salt used as the coolant. In 1968 the fuel was switched from {sup 235}U to {sup 233}U. The Molten Salt Reactor Experiment was canceled in 1969 at which time approximately 4800 kg of salt was transferred to the fuel drain tanks. There was about 36.3 kg of uranium, 675 grams of plutonium and various fission products present in the fuel salt. The salt was allowed to solidify in the fuel drain tanks. The salt was heated on a yearly basis to recombine the fluorine gas with the uranium salt mixture. In March 1994, a gas sample was taken from the off gas system that indicated {sup 233}U had migrated from the fuel drain tank system to the off gas system. It was found that approximately 2.6 kg of uranium had migrated to the Auxiliary Charcoal Bed (ACB). The ACB is located in the concrete-lined charcoal bed cell which is below ground level located outside the MSRE building. Therefore, there was a concern for the potential of a nuclear criticality accident, although water would have to leak into the chamber for a criticality accident to occur. Unstable carbon/fluorine compounds were also formed when the fluorine reacted with the charcoal in the charcoal bed. The purpose of the proposed measurement system was to perform an accountability measurement to determine the fissile mass of {sup 233}U in the primary vessel. The contents of the primary containment assembly will then be transferred to three smaller containers for long term storage. Calculations were performed using MCNP-DSP to determine the configuration of the measurement system. The information obtained from the time signatures can then be compared to the measurement data to determine the amount of {sup 233}U present in the primary containment assembly.

  11. MEASURING X-RAY VARIABILITY IN FAINT/SPARSELY SAMPLED ACTIVE GALACTIC NUCLEI

    SciTech Connect

    Allevato, V.; Paolillo, M.; Papadakis, I.; Pinto, C.

    2013-07-01

    We study the statistical properties of the normalized excess variance of variability process characterized by a ''red-noise'' power spectral density (PSD), as in the case of active galactic nuclei (AGNs). We perform Monte Carlo simulations of light curves, assuming both a continuous and a sparse sampling pattern and various signal-to-noise ratios (S/Ns). We show that the normalized excess variance is a biased estimate of the variance even in the case of continuously sampled light curves. The bias depends on the PSD slope and on the sampling pattern, but not on the S/N. We provide a simple formula to account for the bias, which yields unbiased estimates with an accuracy better than 15%. We show that the normalized excess variance estimates based on single light curves (especially for sparse sampling and S/N < 3) are highly uncertain (even if corrected for bias) and we propose instead the use of an ''ensemble estimate'', based on multiple light curves of the same object, or on the use of light curves of many objects. These estimates have symmetric distributions, known errors, and can also be corrected for biases. We use our results to estimate the ability to measure the intrinsic source variability in current data, and show that they could also be useful in the planning of the observing strategy of future surveys such as those provided by X-ray missions studying distant and/or faint AGN populations and, more in general, in the estimation of the variability amplitude of sources that will result from future surveys such as Pan-STARRS and LSST.

  12. BDNF Methylation and Maternal Brain Activity in a Violence-Related Sample

    PubMed Central

    Moser, Dominik A.; Paoloni-Giacobino, Ariane; Stenz, Ludwig; Adouan, Wafae; Manini, Aurélia; Suardi, Francesca; Cordero, Maria I.; Vital, Marylene; Sancho Rossignol, Ana; Rusconi-Serpa, Sandra; Ansermet, François; Dayer, Alexandre G.; Schechter, Daniel S.

    2015-01-01

    It is known that increased circulating glucocorticoids in the wake of excessive, chronic, repetitive stress increases anxiety and impairs Brain-Derived Neurotrophic Factor (BDNF) signaling. Recent studies of BDNF gene methylation in relation to maternal care have linked high BDNF methylation levels in the blood of adults to lower quality of received maternal care measured via self-report. Yet the specific mechanisms by which these phenomena occur remain to be established. The present study examines the link between methylation of the BDNF gene promoter region and patterns of neural activity that are associated with maternal response to stressful versus non-stressful child stimuli within a sample that includes mothers with interpersonal violence-related PTSD (IPV-PTSD). 46 mothers underwent fMRI. The contrast of neural activity when watching children—including their own—was then correlated to BDNF methylation. Consistent with the existing literature, the present study found that maternal BDNF methylation was associated with higher levels of maternal anxiety and greater childhood exposure to domestic violence. fMRI results showed a positive correlation of BDNF methylation with maternal brain activity in the anterior cingulate (ACC), and ventromedial prefrontal cortex (vmPFC), regions generally credited with a regulatory function toward brain areas that are generating emotions. Furthermore we found a negative correlation of BDNF methylation with the activity of the right hippocampus. Since our stimuli focus on stressful parenting conditions, these data suggest that the correlation between vmPFC/ACC activity and BDNF methylation may be linked to mothers who are at a disadvantage with respect to emotion regulation when facing stressful parenting situations. Overall, this study provides evidence that epigenetic signatures of stress-related genes can be linked to functional brain regions regulating parenting stress, thus advancing our understanding of mothers at risk

  13. BDNF Methylation and Maternal Brain Activity in a Violence-Related Sample.

    PubMed

    Moser, Dominik A; Paoloni-Giacobino, Ariane; Stenz, Ludwig; Adouan, Wafae; Manini, Aurélia; Suardi, Francesca; Cordero, Maria I; Vital, Marylene; Sancho Rossignol, Ana; Rusconi-Serpa, Sandra; Ansermet, François; Dayer, Alexandre G; Schechter, Daniel S

    2015-01-01

    It is known that increased circulating glucocorticoids in the wake of excessive, chronic, repetitive stress increases anxiety and impairs Brain-Derived Neurotrophic Factor (BDNF) signaling. Recent studies of BDNF gene methylation in relation to maternal care have linked high BDNF methylation levels in the blood of adults to lower quality of received maternal care measured via self-report. Yet the specific mechanisms by which these phenomena occur remain to be established. The present study examines the link between methylation of the BDNF gene promoter region and patterns of neural activity that are associated with maternal response to stressful versus non-stressful child stimuli within a sample that includes mothers with interpersonal violence-related PTSD (IPV-PTSD). 46 mothers underwent fMRI. The contrast of neural activity when watching children-including their own-was then correlated to BDNF methylation. Consistent with the existing literature, the present study found that maternal BDNF methylation was associated with higher levels of maternal anxiety and greater childhood exposure to domestic violence. fMRI results showed a positive correlation of BDNF methylation with maternal brain activity in the anterior cingulate (ACC), and ventromedial prefrontal cortex (vmPFC), regions generally credited with a regulatory function toward brain areas that are generating emotions. Furthermore we found a negative correlation of BDNF methylation with the activity of the right hippocampus. Since our stimuli focus on stressful parenting conditions, these data suggest that the correlation between vmPFC/ACC activity and BDNF methylation may be linked to mothers who are at a disadvantage with respect to emotion regulation when facing stressful parenting situations. Overall, this study provides evidence that epigenetic signatures of stress-related genes can be linked to functional brain regions regulating parenting stress, thus advancing our understanding of mothers at risk for

  14. Development of a fluorescent probe for measurement of peroxyl radical scavenging activity in biological samples.

    PubMed

    Güçlü, Kubilay; Kıbrıslıoğlu, Gülşah; Özyürek, Mustafa; Apak, Reşat

    2014-02-26

    In antioxidant activity testing, it has been argued that assays capable of measuring the inhibitive action against the biologically relevant peroxyl radicals (ROO(•)) from a controllable source are preferable in terms of simulating physiological conditions because ROO(•) is the predominant free radical found in lipid oxidation in foods and biological systems. A new fluorescent probe, p-aminobenzoic acid (PABA), was developed for selective measurement of peroxyl radical scavenging (PRS) activity of biological samples, in view of the fact that the existing PRS assays are quite laborious and require the application of strictly optimized conditions. The earlier probe, β-phycoerythrin, of a similar PRS assay of wide use, oxygen radical absorbance capacity (ORAC), varies from lot to lot of production, undergoes photobleaching, and interacts with polyphenols via non-specific protein binding, while the current probe, fluorescein, undergoes undesired fluorescence (FL) quenching and side reactions. The developed technique is based on the fluorescence decrease of the PABA probe (within an optimal time of 30 min) because of its oxidation by ROO(•), generated from the thermal dissociation of 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH). In the absence of the scavenger, ROO(•) reacted with the probe, generating non-fluorescent products, and caused a decrease in PABA fluorescence, whereas the ROO(•) scavenger resulted in a fluorescence increase because of the inhibition of the probe oxidation by ROO(•). Thus, the fluorescence increment of intact PABA is proportional to the ROO(•) scavenging activity of samples. The linear range of relative fluorescence intensity versus the PABA concentration was in the interval of 0.5-5.0 μM. Assay precision and accuracy were assessed by analyzing two spiked homogenates of liver and kidney at clinically relevant concentrations with 97-105% recovery and 2.3% interday reproducibility. The proposed method was

  15. 40 CFR 59.208 - Charcoal lighter material testing protocol.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... digital air velocity meter, DavisΔ DTA 4000 vane anemometer, or equivalent to method 1A of 40 CFR part 60... Subpart, or use Method 1A of 40 CFR part 60, appendix A. Continuously record a velocity reference point... CFR part 60, appendix A, Method 25 Total Combustion Analysis (TCA) sampling apparatus consisting...

  16. 40 CFR 59.208 - Charcoal lighter material testing protocol.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... digital air velocity meter, DavisΔ DTA 4000 vane anemometer, or equivalent to method 1A of 40 CFR part 60... Subpart, or use Method 1A of 40 CFR part 60, appendix A. Continuously record a velocity reference point... CFR part 60, appendix A, Method 25 Total Combustion Analysis (TCA) sampling apparatus consisting...

  17. 40 CFR 59.208 - Charcoal lighter material testing protocol.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... digital air velocity meter, DavisΔ DTA 4000 vane anemometer, or equivalent to method 1A of 40 CFR part 60... Subpart, or use Method 1A of 40 CFR part 60, appendix A. Continuously record a velocity reference point... CFR part 60, appendix A, Method 25 Total Combustion Analysis (TCA) sampling apparatus consisting...

  18. 40 CFR 59.208 - Charcoal lighter material testing protocol.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... digital air velocity meter, DavisΔ DTA 4000 vane anemometer, or equivalent to method 1A of 40 CFR part 60... Subpart, or use Method 1A of 40 CFR part 60, appendix A. Continuously record a velocity reference point... CFR part 60, appendix A, Method 25 Total Combustion Analysis (TCA) sampling apparatus consisting...

  19. 40 CFR 59.208 - Charcoal lighter material testing protocol.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... digital air velocity meter, DavisΔ DTA 4000 vane anemometer, or equivalent to method 1A of 40 CFR part 60... Subpart, or use Method 1A of 40 CFR part 60, appendix A. Continuously record a velocity reference point... CFR part 60, appendix A, Method 25 Total Combustion Analysis (TCA) sampling apparatus consisting...

  20. POP-ART: thermodynamically correct activated event sampling in complex materials

    NASA Astrophysics Data System (ADS)

    Chubynsky, M. V.; Vocks, Henk; Mousseau, Normand; Barkema, G. T.

    2006-03-01

    Dynamics of complex systems with a rugged energy landscape can be represented as a sequence of rare activated events during which the system jumps between different potential energy minima. The activation-relaxation technique (ART) [1] is an efficient method of sampling such events; however, because of an unknown bias in selecting these events it cannot easily provide thermodynamical information. We present a modification of ART, the properly obeying probability ART (POP-ART) [2]. POP-ART combines short molecular dynamics runs with ART-like activated moves, with an additional accept/reject step designed to satisfy detailed balance and thus reproduce correct thermodynamics. Both correctness and efficiency of the method have been tested using a variety of systems. We mention briefly some ways of extending the approach to obtain correct dynamics as well.[1] G.T. Barkema and N. Mousseau, Phys. Rev. Lett. 77, 4358 (1996)[2] H. Vocks, M.V. Chubynsky, G.T. Barkema and N. Mousseau, J. Chem. Phys., accepted