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Sample records for dioxide delignification summary

  1. Carbon dioxide research plan. A summary

    Energy Technology Data Exchange (ETDEWEB)

    Trivelpiece, Alvin W.; Koomanoff, F. A.; Suomi, Verner E.

    1983-11-01

    The Department of Energy is the lead federal agency for research related to atmospheric carbon dioxide. Its responsibility is to sponsor a program of relevant research, and to coordinate this research with that of others. As part of its responsibilities, the Department of Energy has prepared a research plan. The plan documented in this Summary delineated the logic, objectives, organization, background and current status of the research activities. The Summary Plan is based on research subplans in four specific areas: global carbon cycle, climate effects, vegetative response and indirect effects. These subplans have emanated from a series of national and international workshops, conferences, and from technical reports. The plans have been peer reviewed by experts in the relevant scientific fields. Their execution is being coordinated between the responsible federal and international government agencies and the involved scientific community.

  2. Fundamental Investigations of C1O2 Delignification - Final Report - 07/10/1996 - 07/09/1999

    Energy Technology Data Exchange (ETDEWEB)

    Ragauskas, Arthur J.; McDonough, T. J.

    2001-05-18

    The overall objective of this project was to develop a fundamental understanding of the mechanisms of chlorine dioxide delignification of low kappa kraft pulps and identify new methods of improving the efficiency and effectiveness of this bleaching agent. The approach adopted was to investigate the fundamental structural components of lignin that contribute to delignification reactions with chlorine dioxide. These results were then used to examine new bleaching technologies that will permit enhanced delignification while simultaneously reducing the generation of chlorinated organic compounds.

  3. High Selectivity Oxygen Delignification

    Energy Technology Data Exchange (ETDEWEB)

    Arthur J. Ragauskas

    2005-09-30

    The overall objective of this program was to develop improved extended oxygen delignification (EOD) technologies for current U.S. pulp mill operations. This was accomplished by: (1) Identifying pulping conditions that optimize O and OO performance; (2) Identifying structural features of lignin that enhance reactivity towards EOD of high kappa pulps; (3) Identifying factors minimizing carbohydrate degradation and improve pulp strength of EOD high kappa pulps; (4) Developing a simple, reproducible method of quantifying yield gains from EOD; and (5) Developing process conditions that significantly reduce the capital requirements of EOD while optimizing the yield benefits. Key research outcomes included, demonstrating the use of a mini-O sequence such as (E+O)Dkf:0.05(E+O) or Dkf:0.05(E+O)(E+O) without interstage washing could capture approximately 60% of the delignification efficiency of a conventional O-stage without the major capital requirements associated with an O-stage for conventional SW kraft pulps. The rate of formation and loss of fiber charge during an O-stage stage can be employed to maximize net fiber charge. Optimal fiber charge development and delignification are two independent parameters and do not parallel each other. It is possible to utilize an O-stage to enhance overall cellulosic fiber charge of low and high kappa SW kraft pulps which is beneficial for physical strength properties. The application of NIR and multi-variant analysis was developed into a rapid and simple method of determining the yield of pulp from an oxygen delignification stage that has real-world mill applications. A focus point of this program was the demonstration that Kraft pulping conditions and oxygen delignification of high and low-kappa SW and HW pulps are intimately related. Improved physical pulp properties and yield can be delivered by controlling the H-factor and active alkali charge. Low AA softwood kraft pulp with a kappa number 30 has an average improvement of 2% in

  4. High Selectivity Oxygen Delignification

    Energy Technology Data Exchange (ETDEWEB)

    Lucian A. Lucia

    2005-11-15

    Project Objective: The objectives of this project are as follows: (1) Examine the physical and chemical characteristics of a partner mill pre- and post-oxygen delignified pulp and compare them to lab generated oxygen delignified pulps; (2) Apply the chemical selectivity enhancement system to the partner pre-oxygen delignified pulps under mill conditions (with and without any predetermined amounts of carryover) to determine how efficiently viscosity is preserved, how well selectivity is enhanced, if strength is improved, measure any yield differences and/or bleachability differences; and (3) Initiate a mill scale oxygen delignification run using the selectivity enhancement agent, collect the mill data, analyze it, and propose any future plans for implementation.

  5. National assessment of geologic carbon dioxide storage resources: summary

    Science.gov (United States)

    ,

    2013-01-01

    The U.S. Geological Survey (USGS) recently completed an evaluation of the technically accessible storage resource (TASR) for carbon dioxide (CO2) for 36 sedimentary basins in the onshore areas and State waters of the United States. The TASR is an estimate of the geologic storage resource that may be available for CO2 injection and storage and is based on current geologic and hydrologic knowledge of the subsurface and current engineering practices. By using a geology-based probabilistic assessment methodology, the USGS assessment team members obtained a mean estimate of approximately 3,000 metric gigatons (Gt) of subsurface CO2 storage capacity that is technically accessible below onshore areas and State waters; this amount is more than 500 times the 2011 annual U.S. energy-related CO2 emissions of 5.5 Gt (U.S. Energy Information Administration, 2012, http://www.eia.gov/environment/emissions/carbon/). In 2007, the Energy Independence and Security Act (Public Law 110–140) directed the U.S. Geological Survey to conduct a national assessment of geologic storage resources for CO2 in consultation with the U.S. Environmental Protection Agency, the U.S. Department of Energy, and State geological surveys. The USGS developed a methodology to estimate storage resource potential in geologic formations in the United States (Burruss and others, 2009, USGS Open-File Report (OFR) 2009–1035; Brennan and others, 2010, USGS OFR 2010–1127; Blondes, Brennan, and others, 2013, USGS OFR 2013–1055). In 2012, the USGS completed the assessment, and the results are summarized in this Fact Sheet and are provided in more detail in companion reports (U.S. Geological Survey Geologic Carbon Dioxide Storage Resources Assessment Team, 2013a,b; see related reports at right). The goal of this project was to conduct an initial assessment of storage capacity on a regional basis, and results are not intended for use in the evaluation of specific sites for potential CO2 storage. The national

  6. Carbon dioxide storage in unconventional reservoirs workshop: summary of recommendations

    Science.gov (United States)

    Jones, Kevin B.; Blondes, Madalyn S.

    2015-01-01

    “Unconventional reservoirs” for carbon dioxide (CO2) storage—that is, geologic reservoirs in which changes to the rock trap CO2 and therefore contribute to CO2 storage—including coal, shale, basalt, and ultramafic rocks, were the focus of a U.S. Geological Survey (USGS) workshop held March 28 and 29, 2012, at the National Conservation Training Center in Shepherdstown, West Virginia. The goals of the workshop were to determine whether a detailed assessment of CO2 storage capacity in unconventional reservoirs is warranted, and if so, to build a set of recommendations that could be used to develop a methodology to assess this storage capacity. Such an assessment would address only the technically available resource, independent of economic or policy factors. At the end of the workshop, participants agreed that sufficient knowledge exists to allow an assessment of the potential CO2 storage resource in coals, organic-rich shales, and basalts. More work remains to be done before the storage resource in ultramafic rocks can be meaningfully assessed.

  7. Recent advances in polyoxometalate based delignification

    Science.gov (United States)

    R. H. Atalla; L. A. Weinstock; R. S. Reiner; C. J. Houtman; S. Reichel; C. G. Hill; C. L. Hill

    1999-01-01

    A new delignification technology based on the use of polyoxometalates (POMs) as delignification agents is under development at the USDA Forest Service, Forest Products Labotatory (FPL), in Madison, Wisconsin. These reagents are chlorine free and can be used under conditions wherein they oxidize lignin and chromophores in wood pulp fibers while leaving the cellulose...

  8. Using cavitation for delignification of wood.

    Science.gov (United States)

    Baxi, Pranav B; Pandit, Aniruddha B

    2012-04-01

    The Kraft process is the most widely used chemical process for the removal of lignin and other polymers from wood to obtain cellulosic pulp fibres. In the present study, the effect of cavitation (growth and violent collapse of vapour bubbles in a liquid) on delignification of wood was investigated. Steam was introduced in the reactor in order to study the effect of steam driven hybrid cavitation on delignification. The results obtained were subjected to kinetic analysis. The rates of delignification obtained using hydrodynamic cavitation were about 4-5 orders of magnitude greater than those obtained using acoustic cavitation (rate constants for delignification were 9.78×10(-6) and 6.8×10(-1)min(-1) for acoustic and hydrodynamic cavitation, respectively). The energy imparted by the pump in the hydrodynamic cavitation reactor was much higher than that imparted by the acoustic devices and this was considered to be the cause of the higher delignification rates. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Thermal and Physical Properties of Plutonium Dioxide Produced from the Oxidation of Metal: a Data Summary

    Energy Technology Data Exchange (ETDEWEB)

    Wayne, David M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-01-13

    The ARIES Program at the Los Alamos National Laboratory removes plutonium metal from decommissioned nuclear weapons, and converts it to plutonium dioxide in a specially-designed Direct Metal Oxidation furnace. The plutonium dioxide is analyzed for specific surface area, particle size distribution, and moisture content. The purpose of these analyses is to certify that the plutonium dioxide powder meets or exceeds the specifications of the end-user, and the specifications for the packaging and transport of nuclear materials. Analytical results from plutonium dioxide from ARIES development activities, from ARIES production activities, from muffle furnace oxidation of metal, and from metal that was oxidized over a lengthy time interval in air at room temperature, are presented. The processes studied produce plutonium dioxide powder with distinct differences in measured properties, indicating the significant influence of oxidation conditions on physical properties.

  10. Progress in the development and optimization of polyoxometalate delignification systems

    Science.gov (United States)

    R.H. Atalla; I.A. Weinstock; J.S. Bond; R.S. Reiner; E.L. Springer; C.G. Hill; Yu. Geletii; V.A. Grigoriev; A.J. Bailey; L. Delannoy; C.L. Hill

    2002-01-01

    We have reported the use of polyoxometalates (POMs) as selective, regenerable delignification agents that are inherently thermodynamically stable, and self-buffering. The re-activation with oxygen is under conditions that mineralize the organic byproducts of the delignification process. Thus, the POMs provide the basis for a closed bleach plant wherein the consumable...

  11. The effect of delignification of forest biomass on enzymatic hydrolysis.

    Science.gov (United States)

    Yu, Zhiying; Jameel, Hasan; Chang, Hou-Min; Park, Sunkyu

    2011-10-01

    The effect of delignification methods on enzymatic hydrolysis of forest biomass was investigated using softwood and hardwood that were pretreated at an alkaline condition followed by sodium chlorite or ozone delignification. Both delignifications improved enzymatic hydrolysis especially for softwood, while pretreatment alone was found effective for hardwood. High enzymatic conversion was achieved by sodium chlorite delignification when the lignin content was reduced to 15%, which is corresponding to 0.30-0.35 g/g accessible pore volume, and further delignification showed a marginal effect. Sample crystallinity index increased with lignin removal, but it did not show a correlation with the overall carbohydrate conversion of enzymatic hydrolysis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Comparative Studies of Delignification Caused by Ganoderma Species †

    Science.gov (United States)

    Adaskaveg, J. E.; Gilbertson, R. L.; Blanchette, R. A.

    1990-01-01

    Isolates of six species of Ganoderma in the G. lucidum complex were evaluated for their ability to decay wood of Quercus hypoleucoides A. Camus and Abies concolor (Gord. and Glend.) Lindl. ex. Hildebr. by using in vitro agar block decay tests. Morphological, ultrastructural, and chemical studies of decayed wood were used to determine the extent of delignification or simultaneous decay caused by each species of Ganoderma. All species decayed both white fir and oak wood; however, less percent weight loss (%WL) occurred in white fir than oak. In white fir, isolates of two undescribed Ganoderma species (RLG16161, RLG16162, JEA615, and JEA625) caused significantly higher%WL (21 to 26%) than that in G. colossum, G. oregonense, G. meredithiae, and G. zonatum (10 to 16%). Only Ganoderma sp. isolates JEA615 and JEA625 caused delignification, with JEA615 causing a lignin-to-glucose gram loss ratio of 1.6:1. Morphological and ultrastructural studies confirmed delignification by this fungus and showed that some delignification had occurred by all of the species, although areas of delignification were limited to small regions adjacent to simultaneously decayed cells. In oak, G. colossum caused significantly less%WL (22 to 35%) than the other species (38 to 52%). All of the species, except G. meredithiae, caused delignification with lignin-to-glucose gram loss ratios ranging from 1.4 to 4.9:1. Extensive delignification by isolates of G. colossum and G. oregonense was observed; moderate delignification was caused by the other species. Ganoderma meredithiae caused a simultaneous decay, with only small localized regions of cells delignified, while delignification by G. zonatum was irregular, with specific zones within the cell wall delignified. The thermophilic and chlamydosporic G. colossum has the capacity to cause extensive delignification and appears ideally suited for use in lignin degradation studies and biotechnological applications of lignin-degrading fungi. Images PMID

  13. [Measurements of surface ocean carbon dioxide partial pressure during WOCE]. Summary of research progress

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-31

    This paper discusses the research progress of the second year of research under ``Measurement of Surface Ocean Carbon Dioxide Partial Pressure During WOCE`` and proposes to continue measurements of underway pCO{sub 2}. During most of the first year of this grant, our efforts to measure pCO{sub 2} on WOCE WHP legs were frustrated by ship problems. The R/V Knorr, which was originally scheduled to carry out the first work on WHP lines P19 and P16 in the southeastem Pacific during the 1990-91 austral summer, was delayed in the shipyard during her mid-life refit for more than a year. In the interim, the smaller R/V Thomas Washington, was pressed into service to carry out lower-latitude portions of WHP lines P16 and P17 during mid-1991 (TUNES Expedition). We installed and operated our underway chromatographic system on this expedition, even though space and manpower on this smaller vessel were limited and no one from our group would be aboard any of the 3 WHP expedition legs. The results for carbon dioxide and nitrous oxide are shown. A map of the cruise track is shown for each leg, marked with cumulative distance. Following each track is a figure showing the carbon dioxide and nitrous oxide results as a function of distance along this track. The results are plotted as dry-gas mole fractions (in ppm and ppb, respectively) in air and in gas equilibrated with surface seawater at a total pressure equal to the barometric pressure. The air data are plotted as a 10-point running mean, and appear as a roughly horizontal line. The seawater data are plotted as individual points, using a 5-point Gaussian smoother. Equal values Of xCO{sub 2} in air and surface seawater indicate air-sea equilibrium.

  14. Alkaline Peroxide Delignification of Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Mittal, Ashutosh [Biosciences; Katahira, Rui [National; Donohoe, Bryon S. [Biosciences; Black, Brenna A. [National; Pattathil, Sivakumar [Complex; Stringer, Jack M. [National; Beckham, Gregg T. [National

    2017-05-30

    Selective biomass fractionation into carbohydrates and lignin is a key challenge in the conversion of lignocellulosic biomass to fuels and chemicals. In the present study, alkaline hydrogen peroxide (AHP) pretreatment was investigated to fractionate lignin from polysaccharides in corn stover (CS), with a particular emphasis on the fate of the lignin for subsequent valorization. The influence of peroxide loading on delignification during AHP pretreatment was examined over the range of 30-500 mg H2O2/g dry CS at 50 degrees C for 3 h. Mass balances were conducted on the solid and liquid fractions generated after pretreatment for each of the three primary components, lignin, hemicellulose, and cellulose. AHP pretreatment at 250 mg H2O2/g dry CS resulted in the pretreated solids with more than 80% delignification consequently enriching the carbohydrate fraction to >90%. Two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy of the AHP pretreated residue shows that, under high peroxide loadings (>250 mg H2O2/g dry CS), most of the side chain structures were oxidized and the aryl-ether bonds in lignin were partially cleaved, resulting in significant delignification of the pretreated residues. Gel permeation chromatography (GPC) analysis shows that AHP pretreatment effectively depolymerizes CS lignin into low molecular weight (LMW) lignin fragments in the aqueous fraction. Imaging of AHP pretreated residues shows a more granular texture and a clear lamellar pattern in secondary walls, indicative of layers of varying lignin removal or relocalization. Enzymatic hydrolysis of this pretreated residue at 20 mg/g of glucan resulted in 90% and 80% yields of glucose and xylose, respectively, after 120 h. Overall, AHP pretreatment is able to selectively remove more than 80% of the lignin from biomass in a form that has potential for downstream valorization processes and enriches the solid pulp into a highly digestible material.

  15. Using Carbon Dioxide to Enhance Recovery of Methane from Gas Hydrate Reservoirs: Final Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    McGrail, B. Peter; Schaef, Herbert T.; White, Mark D.; Zhu, Tao; Kulkarni, Abhijeet S.; Hunter, Robert B.; Patil, Shirish L.; Owen, Antionette T.; Martin, P F.

    2007-09-01

    Carbon dioxide sequestration coupled with hydrocarbon resource recovery is often economically attractive. Use of CO2 for enhanced recovery of oil, conventional natural gas, and coal-bed methane are in various stages of common practice. In this report, we discuss a new technique utilizing CO2 for enhanced recovery of an unconventional but potentially very important source of natural gas, gas hydrate. We have focused our attention on the Alaska North Slope where approximately 640 Tcf of natural gas reserves in the form of gas hydrate have been identified. Alaska is also unique in that potential future CO2 sources are nearby, and petroleum infrastructure exists or is being planned that could bring the produced gas to market or for use locally. The EGHR (Enhanced Gas Hydrate Recovery) concept takes advantage of the physical and thermodynamic properties of mixtures in the H2O-CO2 system combined with controlled multiphase flow, heat, and mass transport processes in hydrate-bearing porous media. A chemical-free method is used to deliver a LCO2-Lw microemulsion into the gas hydrate bearing porous medium. The microemulsion is injected at a temperature higher than the stability point of methane hydrate, which upon contacting the methane hydrate decomposes its crystalline lattice and releases the enclathrated gas. Small scale column experiments show injection of the emulsion into a CH4 hydrate rich sand results in the release of CH4 gas and the formation of CO2 hydrate

  16. Process parameters affecting the delignification of eucalyptus kraft pulp with peroxyacetic acid

    OpenAIRE

    Chandranupap, P.; Chaivichit, P.; Chandranupap, P.

    2004-01-01

    Various process parameters affecting eucalyptus kraft pulp delignification with peroxyacetic acid were investigated. The results showed that pH was an important factor. The delignification rate increased with increasing pH to the value of 6. High delignification rate was obtained when the pulp was chelated with Na4-EDTA prior to the peroxyacetic acid stage. Therefore, delignification reaction rate depends on peroxyacid charge, temperature, pH and metal content of pulp.

  17. Summary

    International Nuclear Information System (INIS)

    2004-01-01

    The fourth workshop of the OECD/NEA Forum on Stakeholder Confidence (FSC) was hosted by ONDRAF/NIRAS, the Belgian Agency for Radioactive Waste Management and enriched fissile materials. The central theme of the workshop was ''Dealing with interests, values and knowledge in managing risk''within the Belgian context of local partnerships for the long term management of low-level, short-lived radioactive waste. The four-day workshop started with a half-day session in Brussels giving a general introduction on the Belgian context and the local partnership methodology. This was followed by community visits to three local partnerships, PaLoFF in Fleurus-Farciennes, MONA in Mol, and STOLA in Dessel. After the visits, the workshop continued with two full-day sessions in Brussels. One hundred and nineteen registered participants, representing 13 countries, attended the workshop or participated in the community visits. About two thirds were Belgian stakeholders; the remainder came from FSC member organisations. The participants included representatives of municipal governments, civil society organisations, government agencies, industrial companies, the media, and international organisations as well as private citizens, consultants and academics. This Executive Summary gives an overview of the presentations and discussions that took place at the workshop and the community visits. The structure of the Executive Summary follows the structure of the workshop itself. Complementary to this Executive Summary and also provided with this document, is a NEA Secretariat's reflection aiming to place the main lessons of the workshop into an international perspective. (author)

  18. Delignification kinetics of corn stover in lime pretreatment.

    Science.gov (United States)

    Kim, Sehoon; Holtzapple, Mark T

    2006-03-01

    Corn stover was pretreated with excess calcium hydroxide (0.5 g Ca(OH)(2)/g raw biomass) in non-oxidative and oxidative conditions at 25, 35, 45, and 55 degrees C. The delignification kinetic model of corn stover used three first-order reactions with following forms: W(L) = 0.09 x exp(-infinity x t) + 0.28 x exp(-k(2) x t) + 0.63 x exp(-k(3) x t) in non-oxidative pretreatment; W(L) = 0.16 x exp(-infinity x t) + 0.27 x exp(-k(2) x t) + 0.57 x exp(-k(3) x t) in oxidative pretreatment. The first term corresponds to the initial phase, which is essentially infinite at the time scale of the reaction (weeks). The second and third terms correspond to the bulk and residual phases of delignification. The activation energies for delignification in the oxidative lime pretreatment reactions were estimated as 50.15 and 54.21 kJ/mol in the bulk and residual phases, respectively, which are similar to the Kraft delignification of bagasse, but much less than in Kraft delignification of wood.

  19. Study of "napier grass" delignification for production of cellulosic derivatives.

    Science.gov (United States)

    de Araújo Morandim-Giannetti, Andreia; Albuquerque, Tiago Santos; de Carvalho, Renata Kobal Campos; Araújo, Ramires Menezes Silva; Magnabosco, Rodrigo

    2013-01-30

    Recently, much research on the evaluation of new cellulose sources has been developed. In this context, a promising source is "napier grass", which contains 30.40% lignin, 36.34% cellulose, and 34.12% hemicellulose. In this work, conditions for the delignification of "napier grass" in the laboratory were studied by using calcium oxide (CaO) and hydrogen peroxide (H(2)O(2)). The best pulping conditions were 9.00% CaO for a period of 2.73 h, which resulted in 74.99% delignification and 66.58% cellulose. The best conditions for the bleaching process were pH 12 and hydrogen peroxide at concentration of 4.2% for 6h, at a temperature of 40 °C, which gave 90.98% delignification and 99.21% cellulose. The analyses were performed by using weight percent. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Pretreatment of Acacia nilotica Sawdust by Catalytic Delignification and Its Fractal Kinetic Modeling

    Science.gov (United States)

    Mallick, Abhyuday; Ash, Soumendra Nath; Mahapatra, Debashis Kumar

    2016-04-01

    Alkaline delignification of Acacia nilotica heartwood has been carried out using 10 % Sodium hydroxide and Sodium sulphide as the cooking liquor. Delignification was carried out at 373, 393, 403 and 413 K on Acacia nilotica sawdust of particle-sizes 70, 100 and 120 mesh, for durations ranging from 1 to 3 h. The reactions were carried out in presence and in absence of Ferrous sulphate to determine its catalytic properties in delignification. Maximum delignification achieved was 82.7 %, based on Klason lignin, in 3 h at 413 K for 120 mesh feed. The activation energies for delignification were 20.9275 and 35 kJ/mol, respectively, in presence and in absence of Ferrous sulphate, indicating its significant catalytic effect. A kinetic model for delignification was developed by modification of the Nuclei Growth model. Delignification extent could be predicted from the developed model quite accurately, with R2 values ranging from 0.947 to 0.99.

  1. Polyoxometalates in Oxidative Delignification of Chemical Pulps: Effect on Lignin

    Directory of Open Access Journals (Sweden)

    Kolby Hirth

    2010-03-01

    Full Text Available Chemical pulps are produced by chemical delignification of lignocelluloses such as wood or annual non-woody plants. After pulping (e.g., kraft pulping, the remaining lignin is removed by bleaching to produce a high quality, bright paper. The goal of bleaching is to remove lignin from the pulp without a negative effect on the cellulose; for this reason, delignification should be performed in a highly selective manner. New environmentally-friendly alternatives to conventional chlorine-based bleaching technologies (e.g., oxygen, ozone, or peroxide bleaching have been suggested or implemented. In an attempt to find inorganic agents that mimic the action of highly selective lignin-degrading enzymes and that can be applicable in industrial conditions, the researchers have focused on polyoxometalates (POMs, used either as regenerable redox reagents (in anaerobic conditions or as catalysts (in aerobic conditions of oxidative delignification. The aim of this paper is to review the basic concepts of POM delignification in these two processes.

  2. Electrochemical delignification of wood pulp using polyoxometalate mediators

    Science.gov (United States)

    R.S. Reiner; E.L. Springer; R.H. Atalla

    2003-01-01

    It has been found that polyoxometalates (POMs) can act as mediators in the electrochemical oxidation of lignin in pulps. An electrochemical cell, with a Nafion® membrane separating the anode and cathode compartments, was used in the delignification experiments. A softwood kraft pulp was placed in the anode compartment with a buffered 0.01M solution of the...

  3. Comparison of hydrophilic variation and bioethanol production of furfural residues after delignification pretreatment.

    Science.gov (United States)

    Bu, Lingxi; Tang, Yong; Xing, Yang; Zhang, Weiming; Shang, Xinhui; Jiang, Jianxin

    2014-01-01

    Furfural residue (FR) is a waste lignocellulosic material with enormous potential for bioethanol production. In this study, bioethanol production from FR after delignification was compared. Hydrophilic variation was measured by conductometric titration to detect the relationship between hydrophilicity and bioethanol production. It was found that ethanol yield increased as delignification enhanced, and it reached up to 75.6% of theoretical yield for samples with 8.7% lignin. The amount of by-products decreased as delignification increased. New inflection points appeared in conductometric titration curves of samples that were partially delignified, but they vanished in the curves of the highly delignified samples. Total charges and carboxyl levels increased after slight delignification, and they decreased upon further delignification. These phenomena suggested some new hydrophilic groups were formed during pretreated delignification, which would be beneficial to enzymatic hydrolysis. However, some newly formed groups may act as toxicant to the yeast during simultaneous saccharification and fermentation.

  4. Fundamental understanding of distracted oxygen delignification efficiency by dissolved lignin during biorefinery process of eucalyptus.

    Science.gov (United States)

    Zhao, Huifang; Li, Jing; Zhang, Xuejin

    2018-02-27

    In this work, a fundamental understanding of oxygen delignification distracted by dissolved lignin was investigated. In the new biorefinery model of shortening kraft pulping integrated with extended oxygen delignification process, increasing content of residual lignin in the original pulp could result in enhanced delignification efficiency, higher pulp viscosity and less carbonyl groups. However, the invalid oxygen consumption by dissolved lignin could be increased with the increase of process temperature and alkali dosage. The normalized ultraviolet absorbance (divided by absorbance at 280 nm) also showed that the content of chromophoric group in dissolved lignin decreased with oxygen delignification proceeded, both of which indicated that dissolved lignin could enhance the invalid oxygen consumption. Therefore, a conclusion that replacement of the liquor at the initial phase of oxygen delignification process would balance the enhancement of delignification efficiency and invalid oxygen consumption was achieved. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Extended oxygen delignification of high kappa softwood pulp in a flow-through reactor

    OpenAIRE

    Jafari, Vahid

    2015-01-01

    Julkaistu vain painettuna, saatavuus katso Bibid. Published only in printed form, availability see Bibid Oxygen delignification (O-delignification) is an important tool for improving yield, reducing lignin content of pulp and lowering the bleach chemical consumption in the pulp and paper industries. This process is designed after cooking to maximize the delignification rate in comparison to the final phase of Kraft cooking without sacrificing pulp quality. In order to improve the yield of ...

  6. Closed-mill delignification by design using polyoxometalates

    Science.gov (United States)

    C. J. Houtman; R. S. Reiner; S. E. Reichel; M. J. Birchmeier; C. E. Sullivan; L. A. Weinstock; R. H. Atalla

    1999-01-01

    Polyoxometalates (POMs) are a class of delignification agents that promise to provide the basis for a new closed-mill bleaching technology. The results presented here are based on the use of Na6SiV2W10O40, which is effective in reducing the Kappa number of softwood Kraft pulp from 30 to below 10 with minimal loss in viscosity. A critical part of a viable POM process is...

  7. Comparative Studies of Delignification Caused by Ganoderma Species †

    OpenAIRE

    Adaskaveg, J. E.; Gilbertson, R. L.; Blanchette, R. A.

    1990-01-01

    Isolates of six species of Ganoderma in the G. lucidum complex were evaluated for their ability to decay wood of Quercus hypoleucoides A. Camus and Abies concolor (Gord. and Glend.) Lindl. ex. Hildebr. by using in vitro agar block decay tests. Morphological, ultrastructural, and chemical studies of decayed wood were used to determine the extent of delignification or simultaneous decay caused by each species of Ganoderma. All species decayed both white fir and oak wood; however, less percent w...

  8. Cavitation assisted delignification of wheat straw: a review.

    Science.gov (United States)

    Iskalieva, Asylzat; Yimmou, Bob Mbouyem; Gogate, Parag R; Horvath, Miklos; Horvath, Peter G; Csoka, Levente

    2012-09-01

    Wheat is grown in most of the Indian and Chinese regions and after harvesting, the remaining straw offers considerable promise as a renewable source most suitable for papermaking and as a pulping resource. Delignification of wheat straw offers ample scope for energy conservation by way of the application of the process intensification principles. The present work reviews the pretreatment techniques available for improving the effectiveness of the conventional approach for polysaccharide component separation, softening and delignification. A detailed overview of the cavitation assisted delignification process has been presented based on the earlier literature illustrations and important operational guidelines have been presented for overall low-cost and amenable energy utilization in the processes. The effectiveness of the methods has been evaluated according to yield and properties of the isolated fibers in comparison to the conventional treatment. Also the experimental results of one such non-conventional treatment scheme based on the use of hydrodynamic cavitation have been presented for the pulping of wheat straw. The effect of hydrodynamically induced cavitation on cell wall matrix and its components have been characterized using FT-IR analysis with an objective of understanding the cavitation assisted digestion mechanism on straws. It has been observed that the use of hydrodynamic cavitation does not degrade the fibrillar structure of cellulose but causes relocalisation and partial removal of lignin. Overall it appears that considerable improvement can be obtained due to the use of pretreatment or alternate techniques for delignification, which is an energy intensive step in the paper making industries. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Induction of wheat straw delignification by Trametes species.

    Science.gov (United States)

    Knežević, Aleksandar; Stajić, Mirjana; Jovanović, Vladimir M; Kovačević, Višnja; Ćilerdžić, Jasmina; Milovanović, Ivan; Vukojević, Jelena

    2016-05-24

    Wheat straw is the major crop residue in European countries which makes it the most promising material for bioconversion into biofuels. However, cellulose and hemicellulose are protected with lignin, so delignification is an inevitable phase in lignocellulose processing. The organisms predominantly responsible for its degradation are white-rot fungi and among them Trametes species represent promising degraders due to a well-developed ligninolytic enzyme system. Although numerous studies have confirmed that low molecular weight compounds can induce the production and activity of ligninolytic enzymes it is not clear how this reflects on the extent of delignification. The aim of the study was to assess the capacity of p-anisidine and veratryl alcohol to induce the production and activity of Mn-oxidizing peroxidases and laccases, and wheat straw delignification by six Trametes species. Significant inter- and intraspecific variations in activity and features of these enzymes were found, as well as differences in the potential of lignocellulose degradation in the presence or absence of inducers. Differences in the catalytic properties of synthesized enzyme isoforms strongly affected lignin degradation. Apart from enhanced lignin degradation, the addition of p-anisidine could significantly improve the selectivity of wheat straw ligninolysis, which was especially evident for T. hirsuta strains.

  10. Fungal delignification of lignocellulosic biomass improves the saccharification of cellulosics.

    Science.gov (United States)

    Gupta, Rishi; Mehta, Girija; Khasa, Yogender Pal; Kuhad, Ramesh Chander

    2011-07-01

    The biological delignification of lignocellulosic feedstocks, Prosopis juliflora and Lantana camara was carried out with Pycnoporus cinnabarinus, a white rot fungus, at different scales under solid-state fermentation (SSF) and the fungal treated substrates were evaluated for their acid and enzymatic saccharification. The fungal fermentation at 10.0 g substrate level optimally delignified the P. juliflora by 11.89% and L. camara by 8.36%, and enriched their holocellulose content by 3.32 and 4.87%, respectively, after 15 days. The fungal delignification when scaled up from 10.0 g to 75.0, 200.0 and 500.0 g substrate level, the fungus degraded about 7.69-10.08% lignin in P. juliflora and 6.89-7.31% in L. camara, and eventually enhanced the holocellulose content by 2.90-3.97 and 4.25-4.61%, respectively. Furthermore, when the fungal fermented L. camara and P. juliflora was hydrolysed with dilute sulphuric acid, the sugar release was increased by 21.4-42.4% and the phenolics content in hydrolysate was decreased by 18.46 and 19.88%, as compared to the unfermented substrate acid hydrolysis, respectively. The reduction of phenolics in acid hydrolysates of fungal treated substrates decreased the amount of detoxifying material (activated charcoal) by 25.0-33.0% as compared to the amount required to reduce almost the same level of phenolics from unfermented substrate hydrolysates. Moreover, an increment of 21.1-25.1% sugar release was obtained when fungal treated substrates were enzymatically hydrolysed as compared to the hydrolysis of unfermented substrates. This study clearly shows that fungal delignification holds potential in utilizing plant residues for the production of sugars and biofuels.

  11. Mixed Enzyme Systems for Delignification of Lignocellulosic Biomass

    Directory of Open Access Journals (Sweden)

    Elisa M. Woolridge

    2014-01-01

    Full Text Available The application of enzymes such as laccase and xylanase for the preparation of cellulose from lignocellulosic material is an option for those industries seeking to reduce the use of chlorine-containing bleach agents, thus minimizing the environmental impact of their processes. Mixed hydrolytic and oxidative enzyme systems have been well described in the context of biopulping, and thus provide good precedent regarding effectiveness, despite the susceptibility of xylanase to inactivation by laccase-generated oxidants. This paper examines the progress towards development of sequential and simultaneous mixed enzyme systems to accomplish delignification.

  12. Kinetic modeling of kraft delignification of Eucalyptus globulus

    Energy Technology Data Exchange (ETDEWEB)

    Santos, A.; Rodriguez, F.; Gilarranz, M.A.; Moreno, D.; Garcia-Ochoa, F. [Univ. Complutense, Madrid (Spain). Dept. de Ingenieria Quimica

    1997-10-01

    A kinetic model for the kraft pulping delignification of Eucalyptus globulus is proposed. This model is discriminated among some kinetic expressions often used in the literature, and the kinetic parameters are determined by fitting of experimental results. A total of 25 isothermal experiments at liquor-to-wood ratios of 50 and 5 L/kg have been carried out. Initial, bulk, and residual delignification stages have been observed during the lignin removal, the transitions being, referring to the lignin initial content, about 82 and 3%. Carbohydrate removal and effective alkali-metal and hydrosulfide consumption have been related with the lignin removal by means of effective stoichiometric coefficients for each stage, coefficients also being calculated by fitting of the experimental data. The kinetic model chosen has been used to simulate typical kraft pulping experiments carried out at nonisothermal conditions, using a temperature ramp. The model yields simulated values close to those obtained experimentally for the wood studied and also ably reproduces the trends of the literature data.

  13. Kinetic modelling of laccase mediated delignification of Lantana camara.

    Science.gov (United States)

    Gujjala, Lohit K S; Bandyopadhyay, Tapas K; Banerjee, Rintu

    2016-07-01

    Enzymatic delignification is seen as a green step in biofuels production owing to its specificity towards lignin and its proper understanding requires a kinetic study to decipher intricate details of the process such as thermodynamic parameters viz., activation energy, entropy change and enthalpy change. A system of two coupled kinetic models has been constructed to model laccase mediated delignification of Lantana camara. From the simulated output, activation energy was predicted to be 45.56 and 56.06 kJ/mol, entropy change was observed to be 1.08 × 10(2) and 1.05 × 10(2)cal/mol-K and enthalpy change was determined to be 3.33 × 10(4) and 3.20 × 10(4)cal/mol, respectively from Tessier's and Michaelis Menten model. While comparing the prediction efficiency, it was noticed that Tessier's model gave better performance. Sensitivity analysis was also conducted and it was observed that the model was most sensitive towards temperature dependent kinetic constants. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Effect of acid-chlorite delignification on cellulose degree of polymerization.

    Science.gov (United States)

    Hubbell, Christopher A; Ragauskas, Arthur J

    2010-10-01

    Two types of pure cellulose, Avicel PH-101 and Whatman filter paper, were treated with an acid-chlorite delignification procedure in the presence of varying amounts of incorporated lignin, and the molecular weight distributions and degrees of polymerization (DP) of derivatized cellulose were determined by gel permeation chromatography (GPC). Avicel samples with 0% added lignin showed a DP reduction of nearly 5% during acid-chlorite delignification, compared to a 1% drop in DP with 30% added lignin. Lignin-free filter paper samples showed a DP reduction of nearly 35% after hollocellulose delignification. This drop in DP was reduced to less than 12% for samples which contained 30% lignin. Thus, the presence of lignin in biomass samples minimized the DP reduction of cellulose due to acid catalyzed cleavage during acid-chlorite delignification. Copyright 2010 Elsevier Ltd. All rights reserved.

  15. [Synergistic mechanism of steam explosion combined with laccase treatment for straw delignification].

    Science.gov (United States)

    Li, Guanhua; Chen, Hongzhang

    2014-06-01

    Components separation is the key technology in biorefinery. Combination of steam explosion and laccase was used, and synergistic effect of the combined pretreatment was evaluated in terms of physical structure, chemical components and extraction of lignin. The results showed that steam explosion can destroy the rigid structure and increase the specific surface area of straw, which facilitated the laccase pretreatment. The laccase pretreatment can modify the lignin structure based on the Fourier transform infrared test, as a result the delignification of straw was enhanced. Nuclei Growth model with a time dependent rate constant can describe the delignification, and the kinetics parameters indicated that the combined pretreatment improved the reaction sites and made the delignification reaction more sensitive to temperature. The combined pretreatment enhanced delignification, and can be a promising technology as an alternative to the existing pretreatment.

  16. Evaluation of agave fiber delignification by means of microscopy techniques and image analysis.

    Science.gov (United States)

    Hernández-Hernández, Hilda M; Chanona-Pérez, Jorge J; Calderón-Domínguez, Georgina; Perea-Flores, María J; Mendoza-Pérez, Jorge A; Vega, Alberto; Ligero, Pablo; Palacios-González, Eduardo; Farrera-Rebollo, Reynold R

    2014-10-01

    Recently, the use of different types of natural fibers to produce paper and textiles from agave plants has been proposed. Agave atrovirens can be a good source of cellulose and lignin; nevertheless, the microstructural changes that happen during delignification have scarcely been studied. The aim of this work was to study the microstructural changes that occur during the delignification of agave fibers by means of microscopy techniques and image analysis. The fibers of A. atrovirens were obtained from leaves using convective drying, milling, and sieving. Fibers were processed using the Acetosolv pulping method at different concentrations of acetic acid; increasing acid concentration promoted higher levels of delignification, structural damage, and the breakdown of fiber clumps. Delignification followed by spectrometric analysis and microstructural studies were carried out by light, confocal laser scanning and scanning electron microscopy and showed that the delignification process follows three stages: initial, bulk, and residual. Microscopy techniques and image analysis were efficient tools for microstructural characterization during delignification of agave fibers, allowing quantitative evaluation of the process and the development of linear prediction models. The data obtained integrated numerical and microstructural information that could be valuable for the study of pulping of lignocellulosic materials.

  17. Structural elucidation of lignin polymers of Eucalyptus chips during organosolv pretreatment and extended delignification.

    Science.gov (United States)

    Wen, Jia-Long; Sun, Shao-Long; Yuan, Tong-Qi; Xu, Feng; Sun, Run-Cang

    2013-11-20

    Effective delignification of lignocelluloses is a very important to guarantee the economic feasibility of organosolv-based biorefinery. Eucalyptus chips were successively subjected to organosolv pretreatment (AEOP) and extended delignification (ED) process in the present study. The effects of delignification processes were scientifically evaluated by component analysis, SEM, and CP-MAS NMR techniques. It was found that the integrated process of organosolv pretreatment and subsequent delignification resulted in an effective delignification. The fundamental chemistry of the lignin obtained after these processes was thoroughly investigated by FT-IR, multidimensional NMR ((31)P-, (13)C-, and 2D-HSQC NMR), and GPC techniques. It was observed that an extensive cleavage of aryl ether linkages, ethoxylation, and some condensation reactions occurred in AEOP process, while α-oxidation mainly took place in alkaline hydrogen peroxide (AHP) process. It is believed that better understanding the fundamental chemistry of lignin facilitates the optimization of the delignification process. More importantly, well-defined of lignin polymers will facilitate their value-added applications in current and future biorefineries.

  18. Increased delignification by white rot fungi after pressure refining Miscanthus.

    Science.gov (United States)

    Baker, Paul W; Charlton, Adam; Hale, Mike D C

    2015-01-01

    Pressure refining, a pulp making process to separate fibres of lignocellulosic materials, deposits lignin granules on the surface of the fibres that could enable increased access to lignin degrading enzymes. Three different white rot fungi were grown on pressure refined (at 6 bar and 8 bar) and milled Miscanthus. Growth after 28 days showed highest biomass losses on milled Miscanthus compared to pressure refined Miscanthus. Ceriporiopsis subvermispora caused a significantly higher proportion of lignin removal when grown on 6 bar pressure refined Miscanthus compared to growth on 8 bar pressure refined Miscanthus and milled Miscanthus. RM22b followed a similar trend but Phlebiopsis gigantea SPLog6 did not. Conversely, C. subvermispora growing on pressure refined Miscanthus revealed that the proportion of cellulose increased. These results show that two of the three white rot fungi used in this study showed higher delignification on pressure refined Miscanthus than milled Miscanthus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Kinetics of Eucalyptus globulus delignification in a methanol-water medium

    Energy Technology Data Exchange (ETDEWEB)

    Gilarranz, M.A.; Rodriguez, F.; Santos, A.; Oliet, M.; Garcia-Ochoa, F.; Tijero, J. [Univ. Complutense, Madrid (Spain). Dept. de Ingenieria Quimica

    1999-09-01

    The kinetics of Eucalyptus Globulus delignification in methanol-water pulping has been studied. A total of 17 isothermal runs at a liquor-to-wood ratio of 50 L/kg were carried out to develop the kinetic model describing the system. In a first series of experiments, eight models were considered to study the influence of temperature on the delignification rate. The most suitable model, which was discriminated according to statistical criteria, describes delignification as the consecutive dissolution of three lignin species: initial, bulk, and residual lignin, their content in wood being 10, 69, and 21%, respectively. Initial and residual delignification were considered as irreversible reactions and bulk delignification as reversible. The influence of hydrogen ion concentration was taken into account by means of a general power-law expression. The model proposed was taken into account by means of a general power-law expression. The model proposed was validated by reproducing the experimental data from four runs carried out under nonisothermal conditions and a liquor-to-wood ratio of 7 L/kg, which are closer to industrial operating conditions.

  20. Effect of alkaline pretreatment on delignification of wheat straw.

    Science.gov (United States)

    Asghar, Umar; Irfan, Muhammad; Iram, Mehvish; Huma, Zile; Nelofer, Rubina; Nadeem, Muhammad; Syed, Quratulain

    2015-01-01

    This study was conducted to analyse structural changes through scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) after alkaline pretreatment of wheat straw for optimum steaming period. During the study, 2 mm size of substrate was soaked in 2.5% NaOH for 1 h at room temperature and then autoclaved at 121°C for various steaming time (30, 60, 90 and 120 min). Results revealed that residence time of 90 min at 121°C has strong effect on substrate, achieving a maximum cellulose content of 83%, delignification of 81% and hemicellulose content of 10.5%. Further SEM and FTIR spectroscopy confirmed structural modification caused by alkaline pretreatment in substrate. Maximum saccharification yield of 52.93% was achieved with 0.5% enzyme concentration using 2.5% substrate concentration for 8 h of incubation at 50°C. This result indicates that the above-mentioned pretreatment conditions create accessible areas for enzymatic hydrolysis.

  1. Study of Acid Hydrolysis on Organic Waste: Understanding The Effect of Delignification and Particle Size

    Directory of Open Access Journals (Sweden)

    Anwar Nadiem

    2018-01-01

    Full Text Available Organic wastes from Swiettenia marcophylla L, Artocarpus heterophyllus L, Mangifera indica L, and Annona muricata L were prepared by grinding into 0.1875, 0.3750, 0.7500 mm of particle size and delignified by 2% NaOH at 80°C for 90 minutes. Acid dilution hydrolysis process with H2SO4 1% was performed at 150°C for 120 minutes in a closed reactor. The effect of particle size and delignification on and reducing sugar concentration were investigated. The result showed (1 leaves that can be used as raw material to produce hydrogen should have 38–49% cellulose and hemicellulose. (2 Reducing sugar concentration increased with particle size reduction and delignification. (3 the best result with the highest reducing sugar concentration was achieved by 0.1875 mm particle size with delignification on Annona muricata L.

  2. Relationship between lignin structure and delignification degree in Pinus pinaster kraft pulps.

    Science.gov (United States)

    Baptista, C; Robert, D; Duarte, A P

    2008-05-01

    This study examines the structure of residual and dissolved lignins from Pinus pinaster pulps obtained at different degrees of delignification by laboratory conventional kraft pulping. The cooking H factor was varied from 85 to 8049. The residual and dissolved lignin samples were characterised by elemental analysis, residual carbohydrate content, permanganate oxidation and 13C NMR spectroscopy. The reflectance factor of the pulps was also determined in order to tentatively correlate the delignification degree and residual lignin structure with the pulp colour. The obtained results confirmed that the delignification degree increases the condensation of the lignin structure, which might have an influence upon the observed increased pulp colour. The lack of selectivity of kraft pulping process in the case of more delignified pulps was also shown.

  3. Fractionation of bamboo culms by autohydrolysis, organosolv delignification and extended delignification: understanding the fundamental chemistry of the lignin during the integrated process.

    Science.gov (United States)

    Wen, Jia-Long; Sun, Shao-Ni; Yuan, Tong-Qi; Xu, Feng; Sun, Run-Cang

    2013-12-01

    Bamboo (Phyllostachys pubescens) was successfully fractionated using a three-step integrated process: (1) autohydrolysis pretreatment facilitating xylooligosaccharide (XOS) production (2) organosolv delignification with organic acids to obtain high-purity lignin, and (3) extended delignification with alkaline hydrogen peroxide (AHP) to produce purified pulp. The integrated process was comprehensively evaluated by component analysis, SEM, XRD, and CP-MAS NMR techniques. Emphatically, the fundamental chemistry of the lignin fragments obtained from the integrated process was thoroughly investigated by gel permeation chromatography and solution-state NMR techniques (quantitative (13)C, 2D-HSQC, and (31)P-NMR spectroscopies). It is believed that the integrated process facilitate the production of XOS, high-purity lignin, and purified pulp. Moreover, the enhanced understanding of structural features and chemical reactivity of lignin polymers will maximize their utilizations in a future biorefinery industry. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Palo Podrido: Model for Extensive Delignification of Wood by Ganoderma applanatum.

    Science.gov (United States)

    Dill, I; Kraepelin, G

    1986-12-01

    Chemical and micromorphological analysis revealed that South Chilean "palo podrido" results from a white-rot fungus that causes highly selective and extensive delignification. Palo podrido samples from 10 different hardwood trunks (Eucryphia cordifolia, Drimys winteri, and Nothofagus dombeyi) decayed by Ganoderma applanatum were analyzed. Of 14 samples, 11 had extremely low Klason lignin values, ranging from 6.1 to 0.4% (dry weight). The most remarkable and unusual feature was that delignification and defibration were not restricted to small pockets but extended throughout large areas in the interior of trunks subjected to undisturbed rotting over long periods of time. Comparative analysis of water content, swelling capacity, and lignin content led to the conclusion that besides lignin degradation, suppression of the cellulolytic activity of the rotting organisms plays a decisive role. Among various nutrients added to a palo podrido sample (3% residual Klason lignin), the nitrogen source was the only one leading to almost complete cellulose degradation. We suggest that the extremely low nitrogen content (0.037 to 0.073% [dry weight]) of the investigated wood species was the primary cause for the extensive delignification as well as the concomitant suppression of cellulose breakdown. The low temperatures, high humidity, and microaerobic conditions maintained within the decaying trunks are discussed as additional ecological factors favoring delignification in South Chilean rain forests.

  5. Color and Surface Chemistry Changes of Pine Wood Flour after Extraction and Delignification

    Science.gov (United States)

    Yao Chen; Mandla A. Tshabalala; Jianmin Gao; Nicole M. Stark; Yongming Fan

    2014-01-01

    A detailed study was undertaken to examine the color and chemistry changes of pine wood flour when its extractives are removed and when it is delignified. The solvent systems employed were toluene/ethanol (TE), acetone/water (AW), and hot-water (HW), while sodium chlorite/acetic acid were used for delignification (i.e., lignin removal (LR)). Samples were analyzed by...

  6. Delignification outperforms alkaline extraction for xylan fingerprinting of oil palm empty fruit bunch

    NARCIS (Netherlands)

    Murciano Martínez, Patricia; Kabel, Mirjam A.; Gruppen, Harry

    2016-01-01

    Enzyme hydrolysed (hemi-)celluloses from oil palm empty fruit bunches (EFBs) are a source for production of bio-fuels or chemicals. In this study, after either peracetic acid delignification or alkaline extraction, EFB hemicellulose structures were described, aided by xylanase hydrolysis.

  7. Delignification of eucalypt kraft pulp with manganese-substituted polyoxometalate assisted by fungal versatile peroxidase.

    Science.gov (United States)

    Marques, Gisela; Gamelas, José A F; Ruiz-Dueñas, Francisco J; del Rio, José C; Evtuguin, Dmitry V; Martínez, Angel T; Gutiérrez, Ana

    2010-08-01

    Oxidation of the manganese-substituted polyoxometalate [SiW(11)Mn(II)(H(2)O)O(39)](6-) (SiW(11)Mn(II)) to [SiW(11)Mn(III)(H(2)O)O(39)](5-) (SiW(11)Mn(III)), one of the most selective polyoxometalates for the kraft pulp delignification, by versatile peroxidase (VP) was studied. First, SiW(11)Mn(II) was demonstrated to be quickly oxidized by VP at room temperature in the presence of H(2)O(2) (K(m)=6.4+/-0.7 mM and k(cat)=47+/-2s(-1)). Second, the filtrate from eucalypt pulp delignification containing reduced polyoxometalate was treated with VP/H(2)O(2), and 95-100% reoxidation was attained. In this way, it was possible to reuse the liquor from a first SiW(11)Mn(III) stage for further delignification, in a sequence constituted by two polyoxometalate stages, and a short intermediate step consisting of the addition of VP/H(2)O(2) to the filtrate for SiW(11)Mn(II) reoxidation. When the first ClO(2) stage of a conventional bleaching sequence was substituted by the two-stage delignification with polyoxometalate (assisted by VP) a 50% saving in ClO(2) was obtained for similar mechanical strength of the final pulp. (c) 2010 Elsevier Ltd. All rights reserved.

  8. Comparison of Dilute Acid and Ionic Liquid Pretreatment of Switchgrass: Biomass Recalcitrance, Delignification and Enzymatic Saccharification

    Science.gov (United States)

    The efficiency of two biomass pretreatment technologies, dilute acid hydrolysis and dissolution in an ionic liquid, are compared in terms of delignification, saccharification efficiency and saccharide yields with switchgrass serving as a model bioenergy crop. When subject to ionic liquid pretreatme...

  9. Palo Podrido: Model for Extensive Delignification of Wood by Ganoderma applanatum

    Science.gov (United States)

    Dill, Ingrid; Kraepelin, Gunda

    1986-01-01

    Chemical and micromorphological analysis revealed that South Chilean “palo podrido” results from a white-rot fungus that causes highly selective and extensive delignification. Palo podrido samples from 10 different hardwood trunks (Eucryphia cordifolia, Drimys winteri, and Nothofagus dombeyi) decayed by Ganoderma applanatum were analyzed. Of 14 samples, 11 had extremely low Klason lignin values, ranging from 6.1 to 0.4% (dry weight). The most remarkable and unusual feature was that delignification and defibration were not restricted to small pockets but extended throughout large areas in the interior of trunks subjected to undisturbed rotting over long periods of time. Comparative analysis of water content, swelling capacity, and lignin content led to the conclusion that besides lignin degradation, suppression of the cellulolytic activity of the rotting organisms plays a decisive role. Among various nutrients added to a palo podrido sample (3% residual Klason lignin), the nitrogen source was the only one leading to almost complete cellulose degradation. We suggest that the extremely low nitrogen content (0.037 to 0.073% [dry weight]) of the investigated wood species was the primary cause for the extensive delignification as well as the concomitant suppression of cellulose breakdown. The low temperatures, high humidity, and microaerobic conditions maintained within the decaying trunks are discussed as additional ecological factors favoring delignification in South Chilean rain forests. Images PMID:16347235

  10. Coniferyl ferulate incorporation into lignin dramatically enhances the delignification and enzymatic hydrolysis of maize cell walls

    Science.gov (United States)

    Incorporating ester interunit linkages into plant lignins could enhance the delignification and saccharification of fiber for fermentation into ethanol or other industrial products. In this study, we examined how substitution of coniferyl alcohol (a normal monolignol) with 0 to 60% coniferyl ferulat...

  11. Alkaline and ultrasound assisted alkaline pretreatment for intensification of delignification process from sustainable raw-material.

    Science.gov (United States)

    Subhedar, Preeti B; Gogate, Parag R

    2014-01-01

    Alkaline and ultrasound-assisted alkaline pretreatment under mild operating conditions have been investigated for intensification of delignification. The effect of NaOH concentration, biomass loading, temperature, ultrasonic power and duty cycle on the delignification has been studied. Most favorable conditions for only alkaline pretreatment were alkali concentration of 1.75 N, solid loading of 0.8% (w/v), temperature of 353 K and pretreatment time of 6 h and under these conditions, 40.2% delignification was obtained. In case of ultrasound-assisted alkaline approach, most favorable conditions obtained were alkali concentration of 1N, paper loading of 0.5% (w/v), sonication power of 100 W, duty cycle of 80% and pretreatment time of 70 min and the delignification obtained in ultrasound-assisted alkaline approach under these conditions was 80%. The material samples were characterized by FTIR, SEM, XRD and TGA technique. The lignin was recovered from solution by precipitation method and was characterized by FTIR, GPC and TGA technique. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Delignification outperforms alkaline extraction for xylan fingerprinting of oil palm empty fruit bunch.

    Science.gov (United States)

    Murciano Martínez, Patricia; Kabel, Mirjam A; Gruppen, Harry

    2016-11-20

    Enzyme hydrolysed (hemi-)celluloses from oil palm empty fruit bunches (EFBs) are a source for production of bio-fuels or chemicals. In this study, after either peracetic acid delignification or alkaline extraction, EFB hemicellulose structures were described, aided by xylanase hydrolysis. Delignification of EFB facilitated the hydrolysis of EFB-xylan by a pure endo-β-1,4-xylanase. Up to 91% (w/w) of the non-extracted xylan in the delignified EFB was hydrolysed compared to less than 4% (w/w) of that in untreated EFB. Alkaline extraction of EFB, without prior delignification, yielded only 50% of the xylan. The xylan obtained was hydrolysed only for 40% by the endo-xylanase used. Hence, delignification alone outperformed alkaline extraction as pretreatment for enzymatic fingerprinting of EFB xylans. From the analysis of the oligosaccharide-fingerprint of the delignified endo-xylanase hydrolysed EFB xylan, the structure was proposed as acetylated 4-O-methylglucuronoarabinoxylan. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Polyoxometalate delignification of birch kraft pulp and effect on residual lignin

    Science.gov (United States)

    Biljana Bujanovic; Richard S. Reiner; Sally A. Ralph; Rajai H. Atalla

    2011-01-01

    To advance the understanding of delignification with polyoxometalates (POMs) that have been explored for use in bleaching of chemical pulps, the transformation of lignin during anaerobic treatment of birch kraft pulp with an equilibrated POM mixture composed of Na5(+2)[SiV1(-0.1)MoW10(+0.1)O

  14. Increased delignification rate of Dendrocalamus strictus (Roxburgh nees by Schizophyllum commune Fr.; Fr. to reduce chemical consumption during pulping process

    Directory of Open Access Journals (Sweden)

    Vipin Kumar Saini

    2013-08-01

    Full Text Available Pulp and paper industry is traditionally known to be a large contributor to environmental pollution due its largeconsumption of energy and chemicals. To reduce the chemical consumption, rate of delignification was increased bySchizophyllum commune in destructured sample of Dendrocalamus stictus, which was destructured by Impressafiner (compression-cum dewatering process. The extent of delignification was determined and comparison was made between thenon-destructured and destructured samples. The influence of physical parameters like incubation time, moisture level, media,media concentration, pH and temperature were also examined during the study. It was found that rate of delignification wassignificantly 6.43% more in destructured sample than non-destructured sample. Kraft pulping of treated destructured sampleshows 2.59 point reduction in kappa number than untreated non-destructured sample. Thus this paper provides an insight ofthe delignification extent in Dendrocalamus strictus after mechanical operation at varying physical parameters.

  15. Summary of the presentations at the international workshop on reducing carbon dioxide emissions from the developing world: Assessment of benefits, costs and barriers

    International Nuclear Information System (INIS)

    Sathaye, J.; Goldman, N.

    1991-06-01

    The ''International Workshop on Reducing Carbon Dioxide Emissions from the Developing World: Assessment of Benefits, Costs and Barriers'' was the second workshop held as part of a project being conducted by the International Energy Studies Group of Lawrence Berkeley Laboratory, in collaboration with experts from leading institutions across the developing world. The goal of the project is to analyze long-range energy consumption in developing countries and its potential contribution to global climate change. The US Environmental Protection Agency (EPA) is supporting this work, the results of which already have made a key contribution to the technical analysis being used as the basis for discussion by the Energy and Industry Sub-group of the Intergovernmental Panel on Climate Change (IPCC). The main purpose of this workshop was two-fold: (1) to discuss the feasibility of implementing the efficiency improvements and fuel switching measures incorporated into the long-term energy scenarios created for 17 developing countries and (2) to examine the costs and benefits of reducing energy-related carbon dioxide emissions generated by developing countries

  16. Bisphosphine dioxides

    Energy Technology Data Exchange (ETDEWEB)

    Moloy, Kenneth G. (Charleston, WV)

    1990-01-01

    A process for the production of organic bisphosphine dioxides from organic bisphosphonates. The organic bisphosphonate is reacted with a Grignard reagent to give relatively high yields of the organic bisphosphine dioxide.

  17. Bisphosphine dioxides

    Energy Technology Data Exchange (ETDEWEB)

    Moloy, K.G.

    1990-02-20

    A process is described for the production of organic bisphosphine dioxides from organic bisphosphonates. The organic bisphosphonate is reacted with a Grignard reagent to give relatively high yields of the organic bisphosphine dioxide.

  18. Organosolv delignification of Eucalyptus globulus: Kinetic study of autocatalyzed ethanol pulping

    Energy Technology Data Exchange (ETDEWEB)

    Oliet, M.; Rodriguez, F.; Santos, A.; Gilarranz, M.A.; Garcia-Ochoa, F.; Tijero, J.

    2000-01-01

    The autocatalyzed delignification of Eucalyptus globulus in 50% ethanol (w/w) was modeled as the irreversible and consecutive dissolution of initial, bulk, and residual lignin. Their respective contributions to total lignin was estimated as 9, 75, and 16%. Isothermal pulping experiments were carried out to evaluate an empirical kinetic model among eight proposals corresponding to different reaction schemes. The calculated activation energy was found to be 96.5, 98.5, and 40.8 kJ/mol for initial, bulk, and residual delignification, respectively. The influence of hydrogen ion concentration was expressed by a power-law function model. The kinetic model developed here was validated using data from nonisothermal pulping runs.

  19. Characterization of Empty Fruit Bunch Treated with Ionic Liquid Prior to Enzymatic Delignification

    Directory of Open Access Journals (Sweden)

    Revie Financie

    2015-12-01

    Full Text Available The technological utility of enzymes for delignification can be increased by using ionic liquid to open more accessible surface area for biomass transformation into bio-based products. The present paper demonstrates application of ionic liquid (IL [emim][DEP] 1-ethyl-3 methyllimidazolium-diethyl phospate for empty fruit bunch (EFB pretreatment process followed by enzymatic delignification by using Laccase.  It was found that [emim][DEP] increased the performance of the enzyme laccase and henced higher cellulose rich materials, whereas also reduced the lignin content in the EFB. The lowest lignin content obtained from IL-laccase treated EFB was approximately 17.92%, lower than the lignin content in the untreated EFB. Both treated and untreated EFB were characterized in chemical and physical properties by using scanning electron microscope (SEM, fourier transform infrared (FTIR, and thermogravimetric analysis (TGA/DTG to observe the changes resulted from the pretreatment.

  20. Influence of the alkaline delignification on the simultaneous saccharification and fermentation (SSF) of sugar cane bagasse.

    Science.gov (United States)

    Soares, Mariana Lucena; Gouveia, Ester Ribeiro

    2013-11-01

    Ethanol production from steam explosion alkaline delignified bagasse was investigated by saccharification and simultaneous fermentation. Non delignified bagasse (ND) contained 25% lignin, and after alkaline delignification, materials with 6% (D1 - NaOH 1% w/v) and 12% (D05 - NaOH 0.5% w/v) lignin, respectively, were obtained. Ethanol production increased 450% and 733% in relation to ND, when D05 and D1 material, respectively, were used. Higher productivity and EtOH/bagasse were observed for D1. However, higher enzymatic convertibility of cellulose was obtained with 0.5% w/v NaOH. Alkaline delignification increased the ethanol production despite decreased cellulose. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Effect of shortening kraft pulping integrated with extended oxygen delignification on biorefinery process performance of eucalyptus.

    Science.gov (United States)

    Li, Jing; Zhang, Chunyun; Hu, Huichao; Chai, Xin-Sheng

    2016-02-01

    The aim of this work was to study the impact of shortening kraft pulping (KP) process integrated with extended oxygen delignification (OD) on the biorefinery process performance of eucalyptus. Data showed that using kraft pulps with high kappa number could improve the delignification efficiency of OD, reduce hexenuronic acid formation in kraft pulps. Pulp viscosity for a target kappa number of ∼10 was comparable to that obtained from conventional KP and OD process. The energy and alkali consumption in the integrated biorefinery process could be optimized when using a KP pulp with kappa number of ∼27. The process could minimize the overall methanol formation, but greater amounts of carbonate and oxalate were formed. The information from this study will be helpful to the future implementation of short-time KP integrated with extended OD process in actual pulp mill applications for biorefinery, aiming at further improvement in the biorefinery effectiveness of hardwood. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Epigallocatechin gallate incorporation into lignin enhances the alkaline delignification and enzymatic saccharification of cell walls

    Directory of Open Access Journals (Sweden)

    Elumalai Sasikumar

    2012-08-01

    Full Text Available Abstract Background Lignin is an integral component of the plant cell wall matrix but impedes the conversion of biomass into biofuels. The plasticity of lignin biosynthesis should permit the inclusion of new compatible phenolic monomers such as flavonoids into cell wall lignins that are consequently less recalcitrant to biomass processing. In the present study, epigallocatechin gallate (EGCG was evaluated as a potential lignin bioengineering target for rendering biomass more amenable to processing for biofuel production. Results In vitro peroxidase-catalyzed polymerization experiments revealed that both gallate and pyrogallyl (B-ring moieties in EGCG underwent radical cross-coupling with monolignols mainly by β–O–4-type cross-coupling, producing benzodioxane units following rearomatization reactions. Biomimetic lignification of maize cell walls with a 3:1 molar ratio of monolignols and EGCG permitted extensive alkaline delignification of cell walls (72 to 92% that far exceeded that for lignified controls (44 to 62%. Alkali-insoluble residues from EGCG-lignified walls yielded up to 34% more glucose and total sugars following enzymatic saccharification than lignified controls. Conclusions It was found that EGCG readily copolymerized with monolignols to become integrally cross-coupled into cell wall lignins, where it greatly enhanced alkaline delignification and subsequent enzymatic saccharification. Improved delignification may be attributed to internal trapping of quinone-methide intermediates to prevent benzyl ether cross-linking of lignin to structural polysaccharides during lignification, and to the cleavage of ester intra-unit linkages within EGCG during pretreatment. Overall, our results suggest that apoplastic deposition of EGCG for incorporation into lignin would be a promising plant genetic engineering target for improving the delignification and saccharification of biomass crops.

  3. Epigallocatechin gallate incorporation into lignin enhances the alkaline delignification and enzymatic saccharification of cell walls.

    Science.gov (United States)

    Elumalai, Sasikumar; Tobimatsu, Yuki; Grabber, John H; Pan, Xuejun; Ralph, John

    2012-08-13

    Lignin is an integral component of the plant cell wall matrix but impedes the conversion of biomass into biofuels. The plasticity of lignin biosynthesis should permit the inclusion of new compatible phenolic monomers such as flavonoids into cell wall lignins that are consequently less recalcitrant to biomass processing. In the present study, epigallocatechin gallate (EGCG) was evaluated as a potential lignin bioengineering target for rendering biomass more amenable to processing for biofuel production. In vitro peroxidase-catalyzed polymerization experiments revealed that both gallate and pyrogallyl (B-ring) moieties in EGCG underwent radical cross-coupling with monolignols mainly by β-O-4-type cross-coupling, producing benzodioxane units following rearomatization reactions. Biomimetic lignification of maize cell walls with a 3:1 molar ratio of monolignols and EGCG permitted extensive alkaline delignification of cell walls (72 to 92%) that far exceeded that for lignified controls (44 to 62%). Alkali-insoluble residues from EGCG-lignified walls yielded up to 34% more glucose and total sugars following enzymatic saccharification than lignified controls. It was found that EGCG readily copolymerized with monolignols to become integrally cross-coupled into cell wall lignins, where it greatly enhanced alkaline delignification and subsequent enzymatic saccharification. Improved delignification may be attributed to internal trapping of quinone-methide intermediates to prevent benzyl ether cross-linking of lignin to structural polysaccharides during lignification, and to the cleavage of ester intra-unit linkages within EGCG during pretreatment. Overall, our results suggest that apoplastic deposition of EGCG for incorporation into lignin would be a promising plant genetic engineering target for improving the delignification and saccharification of biomass crops.

  4. Effect of delignification process on physical properties of sugarcane baggase paper

    Science.gov (United States)

    Suseno, Natalia; Sapei, Lanny; Purwanto, Edy; Adiarto, Tokok

    2017-05-01

    Wood fiber derived cellulose has been mainly used as the raw material in the papermaking. However, currently the paper production capacity is greater than the availability of wood. To overcome this problem, there have been many attempts to use non-wood fibers as substitutes for papermaking such as the fibrous materials derived from agriculture wastes. In this research, the paper was made from sugarcane bagasse which was previously delignified using soda process. The research was conducted by varying NaOH concentrations of 8 -16%, delignification temperatures of 60- 100°C and times of 30 -150 min. The aim of the research was to study the effect of delignification process on physical properties of sugarcane baggase soda pulping. The results showed the increase in tensile strengths as the NaOH concentrations increased. Tensile strength was increasing up to optimum temperature and time and then decreased. The water uptake results showed the opposite tendencies with those of tensile strength. The optimum condition was achieved at the NaOH concentration of 10 %, delignification temperature of 80 °C, and time of 90 min. Tensile strength and water uptake achieved at this optimum condition were 27.42 N/mm2 and 240 g/m2, respectively.

  5. Streptomyces griseorubens mediated delignification of paddy straw for improved enzymatic saccharification yields.

    Science.gov (United States)

    Saritha, M; Arora, Anju; Singh, Surender; Nain, Lata

    2013-05-01

    Biological pretreatment of paddy straw was carried out using an actinomycete isolate, identified as Streptomyces griseorubens ssr38, for delignification under solid state fermentation and enhanced sugar recovery by enzymatic saccharification. After 10 days incubation, the inoculated paddy straw was extracted with mild alkali and high absorbance at 205 nm was shown by the extracts indicating the ability of S. griseorubens ssr38 to depolymerize/solubilize lignin to a high extent. Also, almost 25% of depolymerized lignin could be recovered as value-added acid-precipitable polymeric lignin (APPL) as compared to controls. Enrichment in carbohydrate content of inoculated paddy straw following delignification led to a high saccharification efficiency of 97.8% upon enzymatic hydrolysis with Accelerase®1500. The study, therefore, proves the potential of actinomycetes, besides the conventionally used white-rot fungi, for biological pretreatment, in the biomass to bioethanol process, with respect to the high extent of delignification, lignin recovery, cellulose enrichment and very high saccharification efficiency. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Hydrodynamic cavitation as a novel approach for delignification of wheat straw for paper manufacturing.

    Science.gov (United States)

    Badve, Mandar P; Gogate, Parag R; Pandit, Aniruddha B; Csoka, Levente

    2014-01-01

    The present work deals with application of hydrodynamic cavitation for intensification of delignification of wheat straw as an essential step in the paper manufacturing process. Wheat straw was first treated with potassium hydroxide (KOH) for 48 h and subsequently alkali treated wheat straw was subjected to hydrodynamic cavitation. Hydrodynamic cavitation reactor used in the work is basically a stator and rotor assembly, where the rotor is provided with indentations and cavitational events are expected to occur on the surface of rotor as well as within the indentations. It has been observed that treatment of alkali treated wheat straw in hydrodynamic cavitation reactor for 10-15 min increases the tensile index of the synthesized paper sheets to about 50-55%, which is sufficient for paper board manufacture. The final mechanical properties of the paper can be effectively managed by controlling the processing parameters as well as the cavitational parameters. It has also been established that hydrodynamic cavitation proves to be an effective method over other standard digestion techniques of delignification in terms of electrical energy requirements as well as the required time for processing. Overall, the work is first of its kind application of hydrodynamic cavitation for enhancing the effectiveness of delignification and presents novel results of significant interest to the paper and pulp industry opening an entirely new area of application of cavitational reactors. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Optimized delignification of wood-derived lignocellulosics for improved enzymatic hydrolysis.

    Science.gov (United States)

    Cullis, Ian F; Mansfield, Shawn D

    2010-08-15

    One of the major bottlenecks in the bioconversion of lignocelluosic feedstocks to liquid ethanol is the recalcitrance of residue following pretreatment, specifically softwood derived residues. Peroxide delignification has previously been shown to effectively aid in the removal of condensed lignaceous moieties from substrates following pretreatment, and thereby improve the hydrolyzability of the polymeric carbohydrates to their monomeric constituents. Despite the effectiveness of peroxide, drawbacks in this system still remain, as the concentration of peroxide required for adequate hydrolysis performance is currently uneconomical. In an attempt to improve the efficacy of the delignification process, we evaluated other post-treatment operations and concurrently attempted to limit the decomposition of peroxide loading; with the over arching aim to improve the efficiency of the bioconversion process. By employing several peroxide stabilizers and pre-chelating the steam exploded recalcitrant substrates, we were able to substantially improve the delignification treatment of Douglas-fir wood chips, and to reduce peroxide loading by more than 50% without negative effects on the hydrolysis rates and yield.

  8. Delignification of sugarcane bagasse using glycerol-water mixtures to produce pulps for saccharification.

    Science.gov (United States)

    Novo, Lísias Pereira; Gurgel, Leandro Vinícius Alves; Marabezi, Karen; Curvelo, Antonio Aprigio da Silva

    2011-11-01

    This paper describes the organosolv delignification of depithed bagasse using glycerol-water mixtures without a catalyst. The experiments were performed using two separate experimental designs. In the first experiment, two temperatures (150 and 190°C), two time periods (60 and 240 min) and two glycerol contents (20% and 80%, v/v) were used. In the second experiment, which was a central composite design, the glycerol content was maintained at 80%, and a range of temperatures (141.7-198.3°C) and time (23-277 min) was used. The best result, obtained with a glycerol content of 80%, a reaction time of 150 min and a temperature of 198.3°C, produced pulps with 54.4% pulp yield, 7.75% residual lignin, 81.4% delignification and 13.7% polyose content. The results showed that high contents of glycerol tend to produce pulps with higher delignification and higher polyoses content in relation to the pulps obtained from low glycerol content reactions. In addition, the proposed method shows potential as a pretreatment for cellulose saccharification. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Characterization of Palo Podrido, a Natural Process of Delignification in Wood †

    Science.gov (United States)

    Agosin, Eduardo; Blanchette, Robert A.; Silva, Herman; Lapierre, Catherine; Cease, Kory R.; Ibach, Rebecca E.; Abad, André R.; Muga, Pedro

    1990-01-01

    Chemical and morphological changes of incipient to advanced stages of palo podrido, an extensively delignified wood, and other types of white rot decay found in the temperate forests of southern Chile were investigated. Palo podrido is a general term for white rot decay that is either selective or nonselective for the removal of lignin, whereas palo blanco describes the white decayed wood that has advanced stages of delignification. Selective delignification occurs mainly in trunks of Eucryphia cordifolia and Nothofagus dombeyi, which have the lowest lignin content and whose lignins have the largest amount of β-aryl ether bonds and the highest syringyl/guaiacyl ratio of all the native woods included in this study. A Ganoderma species was the main white rot fungus associated with the decay. The structural changes in lignin during the white rot degradation were examined by thioacidolysis, which revealed that the β-aryl ether-linked syringyl units were more specifically degraded than the guaiacyl ones, particularly in the case of selective delignification. Ultrastructural studies showed that the delignification process was diffuse throughout the cell wall. Lignin was first removed from the secondary wall nearest the lumen and then throughout the secondary wall toward the middle lamella. The middle lamella and cell corners were the last areas to be degraded. Black manganese deposits were found in some, but not all, selectively delignified samples. In advanced stages of delignification, almost pure cellulose could be found, although with a reduced degree of polymerization. Cellulolytic enzymes appeared to be responsible for depolymerization. A high brightness and an easy refining capacity were found in an unbleached pulp made from selectively delignified N. dombeyi wood. Its low viscosity, however, resulted in poor resistance properties of the pulp. The last stage of degradation (i.e., decomposition of cellulose-rich secondary wall layers) resulted in a gelatinlike

  10. Process intensification of delignification and enzymatic hydrolysis of delignified cellulosic biomass using various process intensification techniques including cavitation.

    Science.gov (United States)

    Nagula, Karuna Narsappa; Pandit, Aniruddha Bhalchandra

    2016-08-01

    Different methods of pretreatment including alkali treatment, treatment with ultrasound, biological treatment using laccase enzyme and combined treatment like ultrasound-laccase for Napier grass have been tried. With alkali pretreatment optimized conditions obtained were sodium hydroxide 0.3% w/v giving 86% delignification at temperature of 80°C, treatment time of 2h. In physical methods of treatment ultrasound, at a temperature of 45°C, treatment time of 2h, operating at frequency 24kHz and power of 100W gave 18% delignification. For laccase pretreatment, optimized conditions obtained were 300rpm impeller speed, enzyme concentration 10U/gm of Napier grass gave 50% delignification with cellulose. The optimized conditions for delignification by using combination treatment of ultrasound & enzymatic were obtained at 24kHz frequency, 100W giving 75% of delignification in 6h. An enhancement in lignin degradation by 25% and reduction in the treatment time from 12 to 6h is achieved as compared to only laccase treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Fractionation of wheat straw by prehydrolysis, organosolv delignification and enzymatic hydrolysis for production of sugars and lignin.

    Science.gov (United States)

    Huijgen, W J J; Smit, A T; de Wild, P J; den Uil, H

    2012-06-01

    Wheat straw was fractionated using a three-step biorefining approach: (1) aqueous pretreatment for hemicellulose prehydrolysis into sugars, (2) organosolv delignification, and (3) enzymatic cellulose hydrolysis into glucose. Prehydrolysis was applied to avoid degradation of hemicellulose sugars during organosolv delignification. Maximum xylose yield obtained was 67% or 0.17 kg/kg straw (prehydrolysis: 175 °C, 30 min, 20mM H(2)SO(4)) compared to 4% in case of organosolv without prehydrolysis (organosolv: 200 °C, 60 min, 60% w/w aqueous ethanol). Prehydrolysis was found to reduce the lignin yield by organosolv delignification due to the formation of 'pseudo-lignin' and lignin recondensation during prehydrolysis. This reduction could partly be compensated by increasing the temperature of the organosolv delignification step. Prehydrolysis substantially improved the enzymatic cellulose digestibility from 49% after organosolv without prehydrolysis to 80% (20 FPU/g substrate). Increasing the organosolv delignification temperature to 220 °C resulted in a maximum enzymatic glucose yield of 93% or 0.36 kg/kg straw. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. High selective delignification using oxidative ionic liquid pretreatment at mild conditions for efficient enzymatic hydrolysis of lignocellulose.

    Science.gov (United States)

    Pang, Zhiqiang; Lyu, Wenkang; Dong, Cuihua; Li, Hongxing; Yang, Guihua

    2016-08-01

    Herein, the oxidative ionic liquid (IL) pretreatment for overcoming recalcitrance of lignocellulose with selective delignification was investigated, and the subsequent enzymatic hydrolysis was evaluated. IL pretreatment incorporating oxygen delignification could enhance lignin extraction with high selectivity at low carbohydrate loss. The dual-action of oxidative decomposition and dissolution by 1-butyl-3-methlimidazolium chloride (BmimCl) on biomass were synergistically acted, accounting for efficient recalcitrance removal. In addition, the mild oxidative IL treatment only slightly converted crystalline cellulose into amorphous structure, and the extensive extraction of the amorphous lignin and carbohydrate resulted to the expose of cellulose with high susceptibility. Correspondingly, the enzymatic hydrolysis of the pretreated lignocellulose was greatly enhanced. The oxidative IL treatment at mild conditions, collaborating BmimCl treatment with oxygen delignification is a promising and effective system for overcoming the robust structure of lignocellulose. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Intensification of delignification and subsequent hydrolysis for the fermentable sugar production from lignocellulosic biomass using ultrasonic irradiation.

    Science.gov (United States)

    Subhedar, Preeti B; Ray, Pearl; Gogate, Parag R

    2018-01-01

    The present work deals with intensification of delignification and subsequent enzymatic hydrolysis of sustainable biomass such as groundnut shells, coconut coir and pistachio shells using ultrasound assisted approach so as to develop an economical approach for obtaining bioethanol. Process intensification, in the current context, is referred to as any improvements giving enhanced rates possibly with lower energy and chemical as well as enzyme requirement for delignification and hydrolysis respectively. Conventional processing for both delignification and enzymatic hydrolysis has also been investigated for establishing the degree of intensification. The obtained results for delignification of biomass established that for conventional alkaline treatment, the extent of delignification for the case of groundnut shells, coconut coir and pistachio shells were 41.8, 45.9 and 38% which increased to 71.1, 89.5 and 78.9% respectively giving almost 80-100% increase for the ultrasound assisted approach. Under optimized conditions, the conventional approach resulted in reducing sugar yields as 10.2, 12.1 and 8.1g/L for groundnut shells, coconut coir and pistachio shells respectively whereas for the case of ultrasound-assisted enzymatic hydrolysis, the obtained yields were 21.3, 23.9 and 18.4g/L in same order of biomass. The material samples were characterized by several characterization techniques for establishing the morphological changes obtained due to the use of ultrasound which were found to be favorable for enhanced delignification and hydrolysis for the ultrasound assisted approach. Overall, the results of this work establish the process intensification benefits due to the application of ultrasound for different sustainable biomass with mechanistic understanding based on the morphological analyses. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Carbon dioxide and climate

    International Nuclear Information System (INIS)

    1991-10-01

    Global climate change is a serious environmental concern, and the US has developed ''An Action Agenda'' to deal with it. At the heart of the US effort is the US Global Change Research Program (USGCRP), which has been developed by the Committee on Earth and Environmental Sciences (CEES) of the Federal Coordinating Council for Sciences, Engineering, and Technology (FCCSET). The USGCRP will provide the scientific basis for sound policy making on the climate-change issue. The DOE contribution to the USGCRP is the Carbon Dioxide Research Program, which now places particular emphasis on the rapid improvement of the capability to predict global and regional climate change. DOE's Carbon Dioxide Research Program has been addressing the carbon dioxide-climate change connection for more than twelve years and has provided a solid scientific foundation for the USGCRP. The expansion of the DOE effort reflects the increased attention that the Department has placed on the issue and is reflected in the National Energy Strategy (NES) that was released in 1991. This Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1991 and gives a brief overview of objectives, organization, and accomplishments. The Environmental Sciences Division of the Office of Health and Environmental Research, Office of Energy Research supports a Carbon Dioxide Research Program to determine the scientific linkage between the rise of greenhouse gases in the atmosphere, especially carbon dioxide, and climate and vegetation change. One facet is the Core CO 2 Program, a pioneering program that DOE established more than 10 years ago to understand and predict the ways that fossil-fuel burning could affect atmospheric CO 2 concentration, global climate, and the Earth's biosphere. Major research areas are: global carbon cycle; climate detection and models of climate change; vegetation research; resource analysis; and, information and integration

  15. A novel and efficient fungal delignification strategy based on versatile peroxidase for lignocellulose bioconversion.

    Science.gov (United States)

    Kong, Wen; Fu, Xiao; Wang, Lei; Alhujaily, Ahmad; Zhang, Jingli; Ma, Fuying; Zhang, Xiaoyu; Yu, Hongbo

    2017-01-01

    The selective lignin-degrading white-rot fungi are regarded to be the best lignin degraders and have been widely used for reducing the saccharification recalcitrance of lignocellulose. However, the biological delignification and conversion of lignocellulose in biorefinery is still limited. It is necessary to develop novel and more efficient bio-delignification systems. Physisporinus vitreus relies on a new versatile peroxidase (VP)-based delignification strategy to remove enzymatic recalcitrance of corn stover efficiently, so that saccharification of corn stover was significantly enhanced to 349.1 mg/g biomass (yield of glucose) and 91.5% (hydrolysis yield of cellulose) at 28 days, as high as levels reached by thermochemical treatment. Analysis of the lignin structure using pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) showed that the total abundance of lignin-derived compounds decreased by 54.0% and revealed a notable demethylation during lignin degradation by P. vitreus . Monomeric and dimeric lignin model compounds were used to confirm the ligninolytic capabilities of extracellular ligninases secreted by P. vitreus . The laccase (Lac) from P. vitreus could not oxidize nonphenolic lignin compounds and polymerized β- O -4 and 5-5' dimers to precipitate which had a negative effect on the enzymatic hydrolysis of corn stover in vitro. However, the VP from P. vitreus could oxidize both phenolic and nonphenolic lignin model compounds as well as break the β- O -4 and 5-5' dimers into monomeric compounds, which were measured by high-performance liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). Moreover, we showed that addition of purified VP in vitro improved the enzymatic hydrolysis of corn stover by 14.1%. From the highly efficient system of enzymatic recalcitrance removal by new white-rot fungus, we identified a new delignification strategy based on VP which could oxidize both phenolic and nonphenolic lignin units and break

  16. COPOLYMERIZATION OF CONIFERYL FERULATE WITH MONOLIGNOLS: IMPACT ON LIGNIN FORMATION AND ALKALINE DELIGNIFICATION OF MAIZE CELL WALLS

    Science.gov (United States)

    Incorporating alkali-labile (ester) interunit linkages into plant lignins could enhance fiber delignification during papermaking and improve the ruminal or industrial biofermentation of structural polysaccharides into organic acids, ethanol, or other products. In this model study, we examined how su...

  17. Effect of light-delignification on mechanical, hydrophobic, and thermal properties of high-strength molded fiber materials.

    Science.gov (United States)

    Wang, Quanliang; Xiao, Shengling; Shi, Sheldon Q; Cai, Liping

    2018-01-17

    This study developed a high-strength molded fiber material (HMFM) using pulp fibers, which could be a good substitute for plastic and solid wood materials. The surface composition, microstructure and thermal properties of HMFM were investigated by XPS, SEM and DSC, respectively. The SEM observations showed that the obvious adhesive substances and agglomeration appeared among fibers, and the inter-fiber contact area and binding tightness increased after the light-delignification. The XPS examination showed that the oxygen-rich composition on the outer surface of HMFM were reduced, and the outer surface coverage of lignin increased from 70.05% to 90.15% after the light-delignification. The DSC observation showed that the thermal stability of HMFM decreased, the temperature for the maximum rate of mass loss decreased from 370 °C to 345.6 °C, and the enthalpy value required for decomposition was reduced from 110.8 J/g to 68.0 J/g after the light-delignification. The mechanical and hydrophobic properties of HMFM were obviously improved after the light-delignification. When the content of lignin decreased from 24.9% to 11.45%, the density of HMFM increased by 6.0%, the tensile strength increased by 22.0%, the bending strength increased by 23.9%, and the water contact angle increased from 64.3°-72.7° to 80.8°-84.3°.

  18. Integrated dynamic model of the alkaline delignification process of Lignocellulosic biomass

    International Nuclear Information System (INIS)

    Fuertez, John; Ruiz, Angela; Alvarez, Hernan; Molina, Alejandro

    2011-01-01

    Although in the public literature there are several studies that describe models of alkaline delignification, they were originally developed for the paper industry, and do not include the effects of important operating variables such as temperature, hydroxide-ion concentration, solid to liquid weight ratio, particle size, biomass composition (hemi cellulose, lignin fraction) and mixing. This lack of detailed models of the pretreatment stages prompted the current study that describes a model which includes the variables listed above and provides an important tool for predicting the degree of lignin removal in lignocellulosic materials such as sugar cane bagasse (Saccharum officinarum L). The model considers kinetic expressions available in the literature. The kinetic parameters were determined by fitting the model to experimental data obtained for that purpose in our lab. The experimental matrix considered eighteen, 24-h isothermal experiments in which bulk and residual delignification stages were observed to occur in a parallel manner. Carbohydrate removal and hydroxide consumption were related to lignin removal by effective stoichiometric coefficients that were calculated by fitting the experimental data. A mixing compartment network model that represented mixing inside the reactor was included into a temporal superstructure based on the similarity between plug flow reactors and ideal batch reactors to model a non-ideally mixed batch reactor. The kinetic model was validated with data obtained in this study.

  19. Exploring the mechanism of high degree of delignification inhibits cellulose conversion efficiency.

    Science.gov (United States)

    Ding, Dayong; Zhou, Xia; You, Tingting; Zhang, Xun; Zhang, Xueming; Xu, Feng

    2018-02-01

    This study explored the mechanism that high degree of delignification (DD) inhibits enzymatic hydrolysis. Sample with DD of 86.22% achieved the highest cellulose conversion of 68.26%, and the cell wall exhibited defibrillation of macrofibrils and erosion of microfibrils during enzymatic hydrolysis. Cracks between microfibrils are formed within the cell wall, getting the largest specific surface area, which greatly enhanced cellulose conversion. However, high DD of 96.58% resulted in dramatic reduction of cellulose conversion to 56.60% which was evidenced to be the synergistic effect of internal cell wall collapse and microfibrils reaggregation. These ultrastructural changes dominated upon this condition and induced a more compact surface structure which significantly hinders the accessibility of cellulase. The CrI value increased after delignification but changed little with the increased DD, suggesting limited influence of DD on crystalline structure. The results indicate that certain amount of lignin retained may be essential to enhance cellulose conversion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Delignification of deciduous wood under the action of hydrogen peroxide and ozone

    Science.gov (United States)

    Mamleeva, N. A.; Kharlanov, A. N.; Lunin, V. V.

    2013-01-01

    Kinetic curves of the dependence of ozone specific absorption ( Q r, sp ) upon the ozonation of aspen wood pretreated with solutions of hydrogen peroxide of various concentrations (from 5 × 10-4 to 2 × 10-1 mol/L) are obtained. The water content in the samples being 56 ± 3%. The initial rate of ozone absorption and total ozone consumption ( Q inlet) are determined. Wood samples are investigated by IR and UV diffuse reflection spectroscopy. Based on the kinetics and spectral data, it is concluded that pretreating wood with a H2O2 solution allows the degree of delignification (DD) to be increased at a constant Q inlet value. The DD is maximal at C_{H_2 O_2 } = 5 × 10^{ - 3} mol/L and is 88% in contrast to a sample ozonated without H2O2 (DD = 85%). The role of pretreatment with hydrogen peroxide and the subsequent action of the O3/H2O2 system in the process of delignification of wood is analyzed.

  1. Comparison of laboratory delignification methods, their selectivity, and impacts on physiochemical characteristics of cellulosic biomass.

    Science.gov (United States)

    Kumar, Rajeev; Hu, Fan; Hubbell, Christopher A; Ragauskas, Arthur J; Wyman, Charles E

    2013-02-01

    Two established delignification methods employing sodium chlorite-acetic acid (SC/AA) and peracetic acid (PAA) are often used, and are reportedly highly selective. However, these reports are mostly for highly recalcitrant and unpretreated softwoods and hardwoods species, and information for less recalcitrant lignocellulosic feedstocks and pretreated biomass is scarce. Furthermore, the effects on cellulose structure are not documented. Thus, in this study, delignification kinetics and selectivity were evaluated when SC/AA and PAA were applied to untreated switchgrass, poplar, corn stover, and pine sawdust; poplar subjected to AFEX, controlled pH, lime, and SO(2) pretreatments; and the cellulose model compounds. Both methods proved effective in removing >90% lignin, but selectivity for lignin and carbohydrates removal was substrate and pretreatment dependent. For untreated biomass, PAA was more selective in removing lignin than SC/AA; however, both methods were less selective for pretreated solids. Cellulose characterizations revealed that PAA had less pronounced impacts on cellulose structure. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Influence of delignification efficiency with alkaline peroxide on the digestibility of furfural residues for bioethanol production.

    Science.gov (United States)

    Wang, Kun; Yang, Haiyan; Chen, Qian; Sun, Run-cang

    2013-10-01

    Furfural residues (FR), the abundant lignocellulosic residues from commercial furfural production, were delignified with alkaline peroxide process and then taken as substrates for ethanol production by simultaneous saccharification and fermentation (SSF). It was apparent that the delignification efficiency was increased with higher chemical addition and temperature, reaching the maximum removal (73.5%) of lignin. The widespread accessible-cellulose in FR favored the enzymatic hydrolysis and achieved the considerable bioconversion (75.7% with 5 FPU+10 IU/g substrate). The delignification process increased the relative glucose content and then the bioconversion efficiency, closely relating to the increased specific surface area. As the cellulose contents were higher than 60%, the final conversions conversely fell to around 75%, probably due to the insufficient utilization of all active cellulose with low enzyme cocktails addition. Although the SSF bioconversion slightly decreased as the elevated amount of fermentable cellulose, the maximum of ethanol concentration (16.9 g/L) was expectedly obtained. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  3. Assessment of integrated process based on autohydrolysis and robust delignification process for enzymatic saccharification of bamboo.

    Science.gov (United States)

    Chen, Tian-Ying; Wen, Jia-Long; Wang, Bing; Wang, Han-Min; Liu, Chuan-Fu; Sun, Run-Cang

    2017-11-01

    In this study, bamboo (Phyllostachys pubescens) was successfully deconstructed using an integrated process (autohydrolysis and subsequent delignification). Xylooligosaccharides, high-purity lignin, and digestible substrates for producing glucose can be consecutively collected during the integrated process. The structural change and fate of lignin during autohydrolysis process was deeply investigated. Additionally, the structural characteristics and active functional groups of the lignin fractions obtained by these delignification processes were thoroughly investigated by NMR (2D-HSQC and 31 P NMR) and GPC techniques. The chemical compositions (S, G, and H) and major linkages (β-O-4, β-β, β-5, etc.) were thoroughly assigned and the frequencies of the major lignin linkages were quantitatively compared. Considering the structural characteristics and molecular weights of the lignin as well as enzymatic saccharification ratio of the substrate, the combination of autohydrolysis and organic base-catalyzed ethanol pretreatment was deemed as a promising biorefinery mode in the future based on bamboo feedstock. Copyright © 2017. Published by Elsevier Ltd.

  4. Fractionation and delignification of empty fruit bunches with low reaction severity for high sugar recovery.

    Science.gov (United States)

    Hong, Jin Young; Kim, Young Soo; Oh, Kyeong Keun

    2013-10-01

    Fractionation and delignification of empty fruit bunches (EFB) was conducted in a series of two steps under low reaction severity with the aim of minimizing the neutralization of hydrolyzates. In EFB underwent acid fractionation, the glucan content was increased to 62.4%, at which point 86.9% of the hemicellulosic sugar and 20.5% of the lignin were extracted from the raw EFB. Xylose-rich hydrolyzate, indicating a high selectivity of 17.7 could be separated. Through the consecutive delignification of acid-fractionated EFB using sodium hydroxide, solid residue with a high glucan content (70.4%) and low hemicellulosic sugar content (3.7%) could be obtained, which indicated that 95.9% of the hemicellulosic sugar and 67.5% of the lignin were extracted based on raw EFB. The final pretreated solid residue was converted to glucose through enzyme hydrolysis, which resulted in an enzymatic digestibility of 76.9% was achieved. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Delignification of miscanthus using ethylenediamine (EDA) with or without ammonia and subsequent enzymatic hydrolysis to sugars.

    Science.gov (United States)

    Padmanabhan, Sasisanker; Schwyter, Philippe; Liu, Zhongguo; Poon, Geoffrey; Bell, Alexis T; Prausnitz, John M

    2016-06-01

    Pretreatment of miscanthus is essential for efficient enzymatic production of cellulosic ethanol. This study reports a possible pretreatment method for miscanthus using aqueous ethylenediamine (EDA) for 30 min at 180 °C with or without ammonia. The mass ratio of miscanthus to EDA was varied from 1:3, 1:1, and 1:0.5, keeping the mass ratio of miscanthus to liquid (EDA + Water) constant at 1:8. The ammonia-to-miscanthus ratio was 1:0.25. After pretreatment with a ratio of 1:3 miscanthus to EDA, about 75 % of the lignin was removed from the raw miscanthus with 90 % retention of cellulose and 50 % of hemicellulose in the recovered solid. Enzymatic hydrolysis of the recovered solid miscanthus gave 63 % glucose and 62 % xylose conversion after 72 h. EDA provides an effective pretreatment for miscanthus, achieving good delignification and enhanced sugar yield by enzyme hydrolysis. Results using aqueous EDA with or without ammonia are much better than those using hot water and compare favorably with those using aqueous ammonia. The delignification efficiency of EDA pretreatment is high compared to that for hot-water pretreatment and is nearly as efficient as that obtained for aqueous-ammonia pretreatment.

  6. Use of polyoxometalate catalysts in ionic liquids to enhance the dissolution and delignification of woody biomass.

    Science.gov (United States)

    Sun, Ning; Jiang, Xinyu; Maxim, Mirela L; Metlen, Andreas; Rogers, Robin D

    2011-01-17

    A well-known polyoxometalate, [PV₂Mo₁₀O₄₀]⁵⁻, in both acidic (acidic POM, H₅[PV₂Mo₁₀O₄₀]) and ionic liquid-compatible form ([C₂mim]POM, [1-ethyl-3-methylimidazolium]₄H[PV₂Mo₁₀O₄₀]), has been studied as a catalyst for the dissolution and delignification of wood in the ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate ([C(2) mim]OAc). Differences were observed with variables such as the form of POM, POM loading, and reaction conditions. Generally, the addition of POM leads to a faster dissolution, a lower lignin content in the recovered cellulose-rich materials (isolated pulp), and a lower isolated yield of lignin due to its oxidation. Acidic POM decreases the lignin content of the pulp without compromising the yield of the pulp. [C₂mim]POM in the IL facilitates greater delignification (lower lignin content in pulp) than the IL with acidic POM; however, the overall pulp yield is also lower indicating some degradation of the carbohydrates. The POM can be recovered with [C₂mim]OAc after evaporation of the reconstitution solvent (e.g., acetone/water) and can be reused, albeit with some loss of POM and loss of POM activity under the current conditions. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Delignification and Enhanced Gas Release from Soil Containing Lignocellulose by Treatment with Bacterial Lignin Degraders.

    Science.gov (United States)

    Rashid, Goran M M; Duran-Pena, Maria Jesus; Rahmanpour, Rahman; Sapsford, Devin; Bugg, Timothy D H

    2017-04-10

    The aim of the study was to isolate bacterial lignin-degrading bacteria from municipal solid waste soil, and to investigate whether they could be used to delignify lignocellulose-containing soil, and enhance methane release. A set of 20 bacterial lignin degraders, including 11 new isolates from municipal solid waste soil, were tested for delignification and phenol release in soil containing 1% pine lignocellulose. A group of 7 strains were then tested for enhancement of gas release from soil containing 1% lignocellulose in small-scale column tests. Using an aerobic pre-treatment, aerobic strains such as Pseudomonas putida showed enhanced gas release from the treated sample, but four bacterial isolates showed 5-10 fold enhancement in gas release in an in situ experiment under microanaerobic conditions: Agrobacterium sp., Lysinibacillus sphaericus, Comamonas testosteroni, and Enterobacter sp.. The results show that facultative anaerobic bacterial lignin degraders found in landfill soil can be used for in situ delignification and enhanced gas release in soil containing lignocellulose. The study demonstrates the feasibility of using an in situ bacterial treatment to enhance gas release and resource recovery from landfill soil containing lignocellulosic waste. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  8. Antioxidant and DNA damage protecting potentials of polysaccharide extracted from Phellinus baumii using a delignification method.

    Science.gov (United States)

    Jin, Qun-Li; Zhang, Zuo-Fa; Lv, Guo-Ying; Cai, Wei-Ming; Cheng, Jun-Wen; Wang, Jian-Gong; Fan, Lei-Fa

    2016-11-05

    A delignification method was employed to extract the polysaccharide from the fruiting body of Phellinus baumii. The three parameters, processing temperature, ratio of water to raw material and amount of acetic acid every time were optimized using the Box-Behnken design. As a result, the optimal extraction conditions were: processing temperature 70.3°C, ratio of water to raw material of 34.7mL/g and amount of acetic acid of 0.32mL every time. Under these conditions, the highest yield of polysaccharide (10.28%) was obtained. The main fraction (PPB-2) purified from PPB was composed of fucose, arabinose, galactose, glucose, xylose and mannose, while glucose was the predominant monosaccharide. PPB-2 exhibited noticeable antioxidant activity and strong protection against oxidative DNA damage. These findings implied that acid-chlorite delignification was a superior method to extract the polysaccharide from P. baumii and PPB-2 may be useful for cancer chemoprevention. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Evidence for room temperature delignification of wood using hydrogen peroxide and manganese acetate as a catalyst.

    Science.gov (United States)

    Lucas, Marcel; Hanson, Susan K; Wagner, Gregory L; Kimball, David B; Rector, Kirk D

    2012-09-01

    Manganese acetate was found to catalyze the oxidative delignification of wood with hydrogen peroxide at room temperature. The delignification reaction was monitored by optical and Raman microscopy, and liquid chromatography/mass spectrometry. When exposed to H(2)O(2) and Mn(OAc)(3) in aqueous solution, poplar wood sections were converted into a fine powder-like material which consisted of individual wood cells within 4 days at room temperature and without agitation. Optical and Raman microscopy provided the spatial distribution of cellulose and lignin in the wood structure, and showed the preferential oxidation of lignin-rich middle lamellae. Raman spectra from the solid residue revealed a delignified and cellulose-rich material. Glucose yields following enzymatic hydrolysis were 20-40% higher in poplar sawdust pretreated with Mn(OAc)(3) for 2, 4, and 7 days at room temperature than those in sawdust exposed to water only for identical durations, suggesting the viability of this mild, inexpensive method for pretreatment of lignocellulosic biomass. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Effects of Incubation Time and Temperature on In Vitro Selective Delignification of Silver Leaf Oak by Ganoderma colossum

    Science.gov (United States)

    Adaskaveg, J. E.; Gilbertson, R. L.; Dunlap, M. R.

    1995-01-01

    The effects of incubation time and temperature on the ability of isolates of the chlamydosporic and thermophilic fungus Ganoderma colossum (Fr.) C. F. Baker to cause selective delignification of Quercus hypoleucoides A. Camus were evaluated by standard in vitro agar block tests. Chemical and scanning electron microscopy studies of decayed wood were used to determine the extent of selective delignification or simultaneous decay caused by each fungal isolate. At 35 deg C, the percent weight loss increased from 6.1% after 4 weeks to a maximum of 32.5 to 33.0% after 16 and 20 weeks of incubation. The average percent Klason lignin-chlorite holocellulose ratios (PKL/CHC) decreased from 0.35 in the control wood block to 0.22 in wood blocks incubated for 12 weeks; this indicated selective delignification. The average PKL/CHC increased for the 16- and 20-week incubation periods, indicating greater removal of polysaccharides during longer incubation periods. In temperature studies, the percent weight loss after 12 weeks was 26 to 27% between 30 and 40 deg C and less than 16% for the 25 and 45 deg C treatments. The average PKL/CHC ranged from 0.18 to 0.16 between 35 and 40 deg C, whereas they were 0.23 and 0.31 for the 25 and 45 deg C treatments, respectively. Scanning electron microscopy confirmed an optimum temperature range near 35 to 40 deg C and incubation times of 8 to 12 weeks for selective delignification. Under these conditions, ray parenchyma, fiber tracheids, and vessels were devoid of middle lamella; pit regions of cells were visible with significantly enlarged apertures; and individual cells were separated and clearly delimited. Extensive delignification of wood occurred throughout the wood blocks evaluated. Incubation times longer than 12 weeks resulted in greater degradation of wood cell walls and thus in greater removal of the polysaccharide component of the wood. For incubation times of 4 weeks or a temperature of 25 deg C, limited to no degradation of cells

  11. Chemical and morphological characterization of sugarcane bagasse submitted to a delignification process for enhanced enzymatic digestibility

    Science.gov (United States)

    2011-01-01

    Background In recent years, biorefining of lignocellulosic biomass to produce multi-products such as ethanol and other biomaterials has become a dynamic research area. Pretreatment technologies that fractionate sugarcane bagasse are essential for the successful use of this feedstock in ethanol production. In this paper, we investigate modifications in the morphology and chemical composition of sugarcane bagasse submitted to a two-step treatment, using diluted acid followed by a delignification process with increasing sodium hydroxide concentrations. Detailed chemical and morphological characterization of the samples after each pretreatment condition, studied by high performance liquid chromatography, solid-state nuclear magnetic resonance, diffuse reflectance Fourier transformed infrared spectroscopy and scanning electron microscopy, is reported, together with sample crystallinity and enzymatic digestibility. Results Chemical composition analysis performed on samples obtained after different pretreatment conditions showed that up to 96% and 85% of hemicellulose and lignin fractions, respectively, were removed by this two-step method when sodium hydroxide concentrations of 1% (m/v) or higher were used. The efficient lignin removal resulted in an enhanced hydrolysis yield reaching values around 100%. Considering the cellulose loss due to the pretreatment (maximum of 30%, depending on the process), the total cellulose conversion increases significantly from 22.0% (value for the untreated bagasse) to 72.4%. The delignification process, with consequent increase in the cellulose to lignin ratio, is also clearly observed by nuclear magnetic resonance and diffuse reflectance Fourier transformed infrared spectroscopy experiments. We also demonstrated that the morphological changes contributing to this remarkable improvement occur as a consequence of lignin removal from the sample. Bagasse unstructuring is favored by the loss of cohesion between neighboring cell walls, as

  12. Chemical and morphological characterization of sugarcane bagasse submitted to a delignification process for enhanced enzymatic digestibility

    Directory of Open Access Journals (Sweden)

    Rezende Camila

    2011-11-01

    Full Text Available Abstract Background In recent years, biorefining of lignocellulosic biomass to produce multi-products such as ethanol and other biomaterials has become a dynamic research area. Pretreatment technologies that fractionate sugarcane bagasse are essential for the successful use of this feedstock in ethanol production. In this paper, we investigate modifications in the morphology and chemical composition of sugarcane bagasse submitted to a two-step treatment, using diluted acid followed by a delignification process with increasing sodium hydroxide concentrations. Detailed chemical and morphological characterization of the samples after each pretreatment condition, studied by high performance liquid chromatography, solid-state nuclear magnetic resonance, diffuse reflectance Fourier transformed infrared spectroscopy and scanning electron microscopy, is reported, together with sample crystallinity and enzymatic digestibility. Results Chemical composition analysis performed on samples obtained after different pretreatment conditions showed that up to 96% and 85% of hemicellulose and lignin fractions, respectively, were removed by this two-step method when sodium hydroxide concentrations of 1% (m/v or higher were used. The efficient lignin removal resulted in an enhanced hydrolysis yield reaching values around 100%. Considering the cellulose loss due to the pretreatment (maximum of 30%, depending on the process, the total cellulose conversion increases significantly from 22.0% (value for the untreated bagasse to 72.4%. The delignification process, with consequent increase in the cellulose to lignin ratio, is also clearly observed by nuclear magnetic resonance and diffuse reflectance Fourier transformed infrared spectroscopy experiments. We also demonstrated that the morphological changes contributing to this remarkable improvement occur as a consequence of lignin removal from the sample. Bagasse unstructuring is favored by the loss of cohesion between

  13. Chemical and morphological characterization of sugarcane bagasse submitted to a delignification process for enhanced enzymatic digestibility.

    Science.gov (United States)

    Rezende, Camila Alves; de Lima, Marisa Aparecida; Maziero, Priscila; deAzevedo, Eduardo Ribeiro; Garcia, Wanius; Polikarpov, Igor

    2011-11-28

    In recent years, biorefining of lignocellulosic biomass to produce multi-products such as ethanol and other biomaterials has become a dynamic research area. Pretreatment technologies that fractionate sugarcane bagasse are essential for the successful use of this feedstock in ethanol production. In this paper, we investigate modifications in the morphology and chemical composition of sugarcane bagasse submitted to a two-step treatment, using diluted acid followed by a delignification process with increasing sodium hydroxide concentrations. Detailed chemical and morphological characterization of the samples after each pretreatment condition, studied by high performance liquid chromatography, solid-state nuclear magnetic resonance, diffuse reflectance Fourier transformed infrared spectroscopy and scanning electron microscopy, is reported, together with sample crystallinity and enzymatic digestibility. Chemical composition analysis performed on samples obtained after different pretreatment conditions showed that up to 96% and 85% of hemicellulose and lignin fractions, respectively, were removed by this two-step method when sodium hydroxide concentrations of 1% (m/v) or higher were used. The efficient lignin removal resulted in an enhanced hydrolysis yield reaching values around 100%. Considering the cellulose loss due to the pretreatment (maximum of 30%, depending on the process), the total cellulose conversion increases significantly from 22.0% (value for the untreated bagasse) to 72.4%. The delignification process, with consequent increase in the cellulose to lignin ratio, is also clearly observed by nuclear magnetic resonance and diffuse reflectance Fourier transformed infrared spectroscopy experiments. We also demonstrated that the morphological changes contributing to this remarkable improvement occur as a consequence of lignin removal from the sample. Bagasse unstructuring is favored by the loss of cohesion between neighboring cell walls, as well as by changes in

  14. Microwave-assisted dissolution and delignification of wood in 1-ethyl-3-methylimidazolium acetate.

    Science.gov (United States)

    Wang, Hui; Maxim, Mirela L; Gurau, Gabriela; Rogers, Robin D

    2013-05-01

    Microwave irradiation can facilitate the dissolution and delignification of lignocelluloses in ionic liquids compared to simple oil bath heating as demonstrated here where 92.5% of 0.5 g ground southern yellow pine was dissolved in 10 g 1-ethyl-3-methylimidazolium acetate using microwave irradiation in only 4 min. Cellulose-rich material (pulp) regenerated from the wood/ionic liquid solution had a lignin content of ~10%; significantly lower than the lignin content of the original wood (31.9%) or that of pulp obtained from the same experiment but using 16 h of oil bath heating (16-24%). The 10% lignin content obtained with the microwave method was close to that of pulp obtained from the oil bath heating method when polyoxometalate catalysts were used (5-9%). Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Addition of ammonia and/or oxygen to an ionic liquid for delignification of miscanthus.

    Science.gov (United States)

    Rodríguez, Héctor; Padmanabhan, Sasisanker; Poon, Geoffrey; Prausnitz, John M

    2011-09-01

    Ammonia and/or oxygen were used to enhance the delignification of miscanthus dissolved in 1-ethyl-3-methylimidazolium acetate at 140°C. After dissolution of the gas at 9 bar, water was added as antisolvent to regenerate the dissolved biomass. In a next step, an acetone/water mixture was used to remove carbohydrate-free lignin from the regenerated biomass. The lignin content in the final product was around 10%, much lower than the ca. 23% lignin content of the raw dry miscanthus. This lignin reduction is achieved without diminution of cellulose or of total carbohydrates recovered, relative to the recovery achieved with the ionic liquid pretreatment in contact with air or nitrogen. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. The delignification effects of white-rot fungal pretreatment on thermal characteristics of moso bamboo.

    Science.gov (United States)

    Zeng, Yelin; Yang, Xuewei; Yu, Hongbo; Zhang, Xiaoyu; Ma, Fuying

    2012-06-01

    Moso bamboo (Phyllostachys pubesescens) is a major bamboo species which is widely used for temporary scaffolding in China. Its fast growing and low ash content make moso bamboo a potential renewable energy resource. In present work, thermal behaviors of moso bamboo and its lignocellulosic fractions were investigated using thermogravimetric analysis. Furthermore, to understand whether the delignification effect of white-rot fungi can promote the thermal decomposition of bamboo especially the lignin component, the changes in lignocellulose components as well as thermal behaviors of bamboo and acid detergent lignin were investigated. The results showed that the white-rot fungal pretreatment is advantageous to thermal decomposition of lignin in bamboo. The weight losses of ADL samples became greater and the thermal processes were accelerated after biopretreatment. The total pyrolysis weight loss increased from 57.14% to 65.07% for Echinodontium taxodii 2538 treated bamboo ADL sample. Copyright © 2011. Published by Elsevier Ltd.

  17. Changes in Lignin Chemistry of Switchgrass due to Delignification by Sodium Hydroxide Pretreatment

    Directory of Open Access Journals (Sweden)

    Woochul Jung

    2018-02-01

    Full Text Available Switchgrass was pretreated with sodium hydroxide (NaOH at various concentrations and pretreatment times to investigate how delignification caused by NaOH affects its lignin chemistry. NaOH resulted in significant delignification ranging from 44.0 to 84.6% depending on pretreatment intensity. While there was no significant glucan loss due to NaOH pretreatment, higher NaOH concentrations removed xylan by up to 28.3%. Nitrobenzene oxidation (NBO was used to study changes in lignin chemistry, and indicated that at higher NaOH concentrations, the amount of 4-hydroxygenzaldehyde (Hy degraded from p-hydroxyphenyl propanol (H lignin units was significantly reduced (p < 0.05. However, amounts of syringic (SA and vanillic (VA acids generated from syringyl (S and guaiacyl (G degradation were greater at higher NaOH concentration. S/G ratio (=0.62 raw switchgrass did not significantly (p > 0.05 change with 15 min pretreatment, but it increased to 0.75 and 0.72, respectively, with 30 and 60 min pretreatments (p < 0.05. Increase in NaOH concentration did not significantly (p > 0.05 change S/G ratio, but H/G ratio (=0.48 raw switchgrass decreased significantly to 0.14 regardless of pretreatment times. Overall, the H unit was found to be more susceptible to NaOH than S and G unit monolignols. Though changes in lignin chemistry due to NaOH concentration were observed, their impact on cellulolytic enzyme action during hydrolysis could not be fully understood. Further studies on lignin isolation may help to determine how these changes in lignin chemistry by NaOH impact cellulolytic enzymes.

  18. Mergeable summaries

    DEFF Research Database (Denmark)

    Agarwal, Pankaj K.; Graham, Graham; Huang, Zengfeng

    2013-01-01

    We study the mergeability of data summaries. Informally speaking, mergeability requires that, given two summaries on two datasets, there is a way to merge the two summaries into a single summary on the two datasets combined together, while preserving the error and size guarantees. This property m...

  19. Integrated delignification and simultaneous saccharification and fermentation of hard wood by a white-rot fungus, Phlebia sp. MG-60.

    Science.gov (United States)

    Kamei, Ichiro; Hirota, Yoshiyuki; Meguro, Sadatoshi

    2012-12-01

    We propose a new process of unified aerobic delignification and anaerobic saccharification and fermentation of wood by a single microorganism, the white-rot fungus Phlebia sp. MG-60. This fungus is able to selectively degrade lignin under aerobic solid state fermentation conditions, and to produce ethanol directly from delignified oak wood under semi-aerobic liquid culture conditions. After 56 d aerobic incubation, 40.7% of initial lignin and negligible glucan were degraded. Then under semi-aerobic conditions without the addition of cellulase, 43.9% of theoretical maximum ethanol was produced after 20 d. Changing from aerobic conditions (biological delignification pretreatment) to semi-aerobic conditions (saccharification and fermentation) enabled the fermentation of wood by solely biological processes. This is the first report of ethanol production from woody biomass using a single microorganism without addition of chemicals or enzymes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Lignocellulosic biomass delignification using aqueous alcohol solutions with the catalysis of acidic ionic liquids: A comparison study of solvents.

    Science.gov (United States)

    Cheng, Fangchao; Zhao, Xin; Hu, Yingcheng

    2018-02-01

    The exploration of effective deconstruction of biomass complex structures and mild fractionation into individual components is a profound challenge for the development of biorefinery. Herein, a biomass fractionation process, via treating biomass in various aqueous alcohol solutions with the catalysis of acidic ionic liquids 1-butyl-3-methylimidazolium hydrogen sulfate, was demonstrated to fractionate coir and poplar into cellulose materials with a lignin content as low as 0.95% and lignin with a delignification rate of up to 98%. The participation of acidic ionic liquids into the solvent system greatly multiplied the biomass fractionation efficiency. The analysis on effects of the chemical structure and solubility parameter of alcohols on the delignification efficiency provided a rational and meaningful way to predict and screen solvent for the biomass fractionation process. Lignin in the present study exhibited similar structure with milled wood lignin, and comparable molecular and thermal properties with the conventional organosolv lignin. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Conversion of Levulinic Acid from Various Herbaceous Biomass Species Using Hydrochloric Acid and Effects of Particle Size and Delignification

    Directory of Open Access Journals (Sweden)

    Indra Neel Pulidindi

    2018-03-01

    Full Text Available Acid catalyzed hydrothermal conversion of levulinic acid (LA from various herbaceous materials including rice straw (RS, corn stover (CS, sweet sorghum bagasse (SSB, and Miscanthus (MS was evaluated. With 1 M HCl, 150 °C, 5 h, 20 g/L solid loading, the yields of LA from untreated RS, CS, SSB and MS based on the glucan content were 60.2, 75.1, 78.5 and 61.7 wt %, respectively. It was also found that the particle size had no significant effect on LA conversion yield with >3 h reaction time. With delignification using simulated green liquor (Na2CO3-Na2S, 20 wt % total titratable alkali (TTA, 40 wt % sulfidity at 200 °C for 15 min, lignin removal was in the range of 64.8–91.2 wt %. Removal of both lignin and xylan during delignification increased the glucan contents from 33.0–44.3 of untreated biomass to 61.7–68.4 wt % of treated biomass. Delignified biomass resulted in much lower conversion yield (50.4–56.0 wt % compared to 60.2–78.5 wt % of untreated biomass. Nonetheless, the concentration of LA in the product was enhanced by a factor of ~1.5 with delignification.

  2. Biological Delignification of Aspen Wood by Solid-State Fermentation with the White-Rot Fungus Merulius tremellosus†

    Science.gov (United States)

    Reid, Ian D.

    1985-01-01

    Solid-state fermentation of aspen (Populus tremuloides) wood with Merulius tremellosus for 8 weeks removed 52% of the lignin but only 12% of the total wood weight, and increased the cellulase digestibility to 53% from 18%. Water-soluble and enzyme-solubilized lignin degradation products accumulated. Delignification was fastest at temperatures between 25 and 32.5°C and at a water-to-wood ratio of 2. Initial pH values between 4 and 6 were optimal; M. tremellosus acidified the wood to below pH 3.5 as it grew. The fungus tolerated CO2 concentrations of at least 14% and O2 concentrations down to 7% in the bulk gas phase. Both simple and complex nitrogen supplements inhibited delignification. Supplementary KH2PO4, MgSO4, CaCl2, thiamine, and trace elements had little effect on the fermentation. Four isolates of M. tremellosus had very similar abilities to delignify aspen wood. Biological delignification with M. tremellosus may be a useful pretreatment for enzymatic saccharification or ruminant feeding. PMID:16346831

  3. Evaluation of hemicellulose removal by xylanase and delignification on SHF and SSF for bioethanol production with steam-pretreated substrates.

    Science.gov (United States)

    Shen, Fei; Kumar, Linoj; Hu, Jinguang; Saddler, Jack N

    2011-10-01

    Steam-pretreated sweet sorghum bagasse (SSB) and Douglas-fir (DF) were employed for SHF and SSF to evaluate the effects of xylanase supplementation and delignification on ethanol production. Results indicated final ethanol concentration in SHF could reach 28.4 g/L (SSB) and 20.4 g/L (DF) by xylanase supplementation with the increase of 46% and 61% in comparison with controls. The delignification could significantly enhance final ethanol concentration to 31.2g/L (SSB) and 30.2 g/L (DF) with the increase of 61% and 138%. In SSF, final ethanol concentration in the delignified SSB and DF arrived at 27.6 g/L and 34.3 g/L with the increase of 26% and 157% compared with controls. However, only 2.2 g/L (SSB) and 6.9 g/L (DF) ethanol were obtained with xylanase supplementation. According to these results, it could be concluded that delignification was beneficial to improve ethanol production of SHF and SSF. The xylanase supplementation (0.12 g protein/g glucan) was only positive to SHF while retarded SSF seriously. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. MEMPELAJARI PROSES PENYULINGAN MINYAK NILAM MELALUI DELIGNIFIKASI DAUN [Study on Distilation Process of Patchouli Oil Through Leaves Delignification

    Directory of Open Access Journals (Sweden)

    Nasruddin1

    2005-12-01

    Full Text Available Research was objected to determine the effect of patchouli leaves preparation on the distillation efficiency and quality of patchouli oil. The patchouli leaves (Pogostemon cablin Benth were taken from Pandan Dulang Village, Muara Enim. It was separated from the stems and dried until maximum moisture content of 15%. Experiment was conducted in two replications base on these treatments, i.e delignification temperature (550C, 800C and fermentation time (2, 4, 6, 8, days. NaOH solution (0,25% was used for delignification. The distillation process was conducted at 100  20C and ambient pressure environment. Patchouli oil quality was expressed as several parameter such as ester numbers, acid numbers, and specific gravity.The result showed that increasing of fermentation time is followed by decreasing of the patchouli oil quality. Delignification at 550C for 6 days was identified as the treatment produced the highest efficiency process which about 2,346% (w/w of patchouli oil that could be extracted and showed specific gravity 0.959, acid number 0,761 and ester number 4,561. All patchouli oil produced using the treatment of fermentation time were in the range of physico-chemical quality standard of patchouli oil given by SNI no 06-2385-1991.

  5. Delignification and detoxification of peanut shell bio-waste using an extremely halophilic laccase from an Aquisalibacillus elongatus isolate.

    Science.gov (United States)

    Rezaie, Rezvan; Rezaei, Shahla; Jafari, Nasrin; Forootanfar, Hamid; Khoshayand, Mohammad Reza; Faramarzi, Mohammad Ali

    2017-11-01

    Lignocellulose bioconversion is a harsh process requiring the use of surfactants and organic solvents. Consequently, the incorporation of laccases in this bioconversion requires the bioprospecting of enzymes that can remain stable under extreme conditions. An extracellular, highly stable laccase was produced by the halophilic isolate Aquisalibacillus elongatus in submerged liquid culture fermentation. Statistical and non-statistical strategies gave the highest enzymatic activity (8.02 U mL -1 ) following addition of glucose (1.7 g L -1 ), copper sulfate (0.8 g L -1 ), urea (15 g L -1 ), and CaCl 2 (0.8 g L -1 ). The enzyme, after purification using a synthetic affinity support, delignified a peanut shell substrate by 45%. A pH of 8.0 and a temperature of 35 °C were optimal for delignification of this bio-waste material. Addition of [Bmim][PF 6 ], 1,4-dioxane, acetone, and HBT promoted this bio-waste delignification. Bio-treatment in the presence of 50% [Bmim][PF 6 ] gave a maximal lignin removal of 87%. The surfactants tested had no significant effects on the delignification yield. The laccase also detoxified the toxic phenols found in peanut shell waste. The high catalytic efficiency of this enzyme against a lignocellulosic sample under extreme conditions suggests the suitability of this laccase for industrial applications.

  6. Fungal treatment of cornstalks enhances the delignification and xylan loss during mild alkaline pretreatment and enzymatic digestibility of glucan.

    Science.gov (United States)

    Yu, Hongbo; Du, Wanqing; Zhang, Ji; Ma, Fuying; Zhang, Xiaoyu; Zhong, Weixin

    2010-09-01

    Fungal treatment with Irpex lacteus was used to enhance the delignification and xylan loss during mild alkaline pretreatment and subsequent enzymatic conversion in this research. The 15-day bio-treatment can modify the lignin structure and increase losses of lignin (from 75.67% to 80.00%) and xylan (from 40.68% to 51.37%) during alkaline pretreatment, making the enzymatic conversion more efficient. The high digestibility of glucan can be obtained after the bio-treatment and alkaline pretreatment at near room-temperature (30 degrees C), and the maximum digestibility increased 14% in comparison with that after the sole alkaline pretreatment. The bio-treatment enhanced delignification and glucan digestibility more significantly when the alkaline pretreatment was performed at lower severity. Additionally, Nuclei Growth model with a time-dependent rate constant can describe well the delignification and xylan loss. Results indicated that the bio-treatment increased the rate constant of initial reaction, but accelerated the decline of rate constant during alkaline pretreatment. (c) 2010 Elsevier Ltd. All rights reserved.

  7. Clean production of corn stover pulp using KOH+NH4OH solution and its kinetic during delignification

    Directory of Open Access Journals (Sweden)

    Sun Yong

    2012-01-01

    Full Text Available The self-made KOH together with NH4OH pulping of corn stover was investigated. The combined alkaline system could effectively remove lignin during pulping. There are three stages of lignin removal during delginification. Approximately 90% of lignin could be removed after temperature reached 150ºC for over 30 minutes. The p-hydroxyl phenol groups in lignin could be completely removed during the delignification reaction. The tendency of the increase of the crystalline degree of cellulose is observed with increase of reaction temperature. The kinetics of delignification is found to be the first order with respect to the remained lignin and the 0.4 order with respect to the remained hydroxide concentration. The activation energy of delignification is 23 kJ/mol. The solution obtained from precipitation of lignin is rich in nitrogen, phosphorous, potassium elements and organic matters. Various techniques including FT-IR, GPC, DSC, were applied to characterize the acid precipitated lignin. The result shows that the lignin with the polydispersity of 1.4 still maintains the p-coumaryl, coniferyl, and sinapyl units in its matrix.

  8. Impact of Hot-Water Extraction on Acetone-Water Oxygen Delignification of Paulownia Spp. and Lignin Recovery

    Directory of Open Access Journals (Sweden)

    Chen Gong

    2014-02-01

    Full Text Available A hardwood-based biorefinery process starting with hot-water extraction (HWE is recommended in order to remove most of the hemicelluloses/xylans before further processing. HWE may be followed by delignification in acetone/water in the presence of oxygen (AWO for the production of cellulose and lignin. In this study, the HWE-AWO sequence was evaluated for its effectiveness at removing lignin from the fast-growing species Paulownia tomentosa (PT and Paulownia elongata (PE, in comparison with the reference species, sugar maple (Acer saccharum, SM. HWE might lead to a remarkable increase in lignin accessibility, and as a result, a greater AWO delignification degree was observed for extracted PT, PE, and SM than for unextracted ones. Organosolv lignin was recovered from the spent liquor of AWO delignification of PT with/without prior HWE and characterized to evaluate the benefits of HWE on the lignin structure and purity. The lignin recovered from the spent liquor of HWE-AWO sequence is of higher purity and lighter color than that recovered from the AWO spent liquor. These properties along with low sulfur content are desirable for lignin high-value applications.

  9. Green oxidations: Titanium dioxide induced tandem oxidation coupling reactions

    OpenAIRE

    Jeena, Vineet; Robinson, Ross S

    2009-01-01

    Summary The application of titanium dioxide as an oxidant in tandem oxidation type processes is described. Under microwave irradiation, quinoxalines have been synthesized in good yields from the corresponding ?-hydroxyketones.

  10. Supercritical carbon dioxide combined with 1-butyl-3-methylimidazolium acetate and ethanol for the pretreatment and enzymatic hydrolysis of sugarcane bagasse.

    Science.gov (United States)

    Silveira, Marcos Henrique Luciano; Vanelli, Bruno Angelo; Corazza, Marcos Lucio; Ramos, Luiz Pereira

    2015-09-01

    The use of green solvents for the partial delignification of milled sugarcane bagasse (1mm particle size) and for the enhancement of its susceptibility to enzymatic hydrolysis was demonstrated. The experiments were carried out for 2h using 40 g of supercritical carbon dioxide combined with 1-butyl-3-methylimidazolium acetate and 15.8 g of ethanol. The effects of temperature (110-180 °C), pressure (195-250 bar) and IL-to-bagasse mass ratio (0:1-1:1) were investigated through a factorial design in which the response variables were the extent of delignification and both anhydroglucose and anhydroxylose contents in the pretreated materials. The highest delignification degree (41%) led to the best substrate for hydrolysis, giving a 70.7 wt% glucose yield after 12h using 5 wt% and Cellic CTec2® (Novozymes) at 10 mg g(-1) total solids. Hence, excellent substrates for hydrolysis were produced with a minimal IL requirement, which could be recovered by ethanol washing for its downstream processing and reuse. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Carbon dioxide and climate

    Energy Technology Data Exchange (ETDEWEB)

    1990-10-01

    Scientific and public interest in greenhouse gases, climate warming, and global change virtually exploded in 1988. The Department's focused research on atmospheric CO{sub 2} contributed sound and timely scientific information to the many questions produced by the groundswell of interest and concern. Research projects summarized in this document provided the data base that made timely responses possible, and the contributions from participating scientists are genuinely appreciated. In the past year, the core CO{sub 2} research has continued to improve the scientific knowledge needed to project future atmospheric CO{sub 2} concentrations, to estimate climate sensitivity, and to assess the responses of vegetation to rising concentrations of CO{sub 2} and to climate change. The Carbon Dioxide Research Program's goal is to develop sound scientific information for policy formulation and governmental action in response to changes of atmospheric CO{sub 2}. The Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1990 and gives a brief overview of objectives, organization, and accomplishments.

  12. Multiple effects of swelling by sodium bicarbonate after delignification on enzymatic saccharification of rice straw.

    Science.gov (United States)

    Kahar, Prihardi; Taku, Kazuo; Tanaka, Shuzo

    2013-12-01

    The multiple effects of pretreatments by chemical delignification using acidified sodium chlorite (ASC) and swelling using sodium bicarbonate (SB) for enzymatic saccharification of rice straw in bioethanol production have been investigated in this study. The treatment with the combination of ASC three times (3× ASC) first and SB later resulted in the significant reduction in Klason lignin content up to 90% (wt./wt.). By the saccharification of the pretreated rice straw with cellulase enzymes, it was confirmed that SB treatment was an important step in the pretreatment process not only to disintegrate the cellulose structure but also to facilitate the amorphization of the crystalline cellulose as well as the extended removal of integrated lignin. Furthermore, FTIR analyses revealed that the crystal type of cellulose appeared to be changed from type I to type II by SB treatment, thereby increasing the cellulose surface area and making it more accessible to the cellulase enzyme. Conversion rate to sugar was remarkably increased when 3× ASC + SB treatments were applied to untreated rice straw, even though the saccharification of the treated rice straw was performed at a low enzyme loading (1/100, wt.-enzymes/wt.-substrate). Conclusively, rice straw could be saccharified at high yield in short time at low cellulase loading, enables the enzymatic saccharification to be more feasible for practical bioethanol production using rice straw as a substrate. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  13. Aqueous-ammonia delignification of miscanthus followed by enzymatic hydrolysis to sugars.

    Science.gov (United States)

    Liu, Zhongguo; Padmanabhan, Sasisanker; Cheng, Kun; Schwyter, Philippe; Pauly, Markus; Bell, Alexis T; Prausnitz, John M

    2013-05-01

    This work concerns the effect of aqueous ammonia pretreatment at four temperatures and at 10, 20 or 30 wt.% ammonia. After 1h, more than 65% delignification is achieved at 150 or 180 °C for high and for low concentrations of ammonia. When the delignified miscanthus is enzymatically hydrolyzed for 96 h using cellulases and beta-glucosidase, conversion of the recovered solid to glucose is 53.4% and to xylose 70.0%. Additional glucose and xylose can be obtained from the ammonia-containing aqueous phase. Increased ammonia concentration leads to better conversion. Fourier-transform infrared and Two-dimensional (13)C-(1)H Heteronuclear Single Quantum Coherence (HSQC) Nuclear Magnetic Resonance spectroscopy provide data for the composition of the pretreated miscanthus and for that of the liquid extract. These spectra indicate that pretreatment with ammonia leads to de-acetylation of the xylan-backbone. The β-O-4' linked aryl ether remains the most abundant linkage in the pretreated miscanthus. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Enhanced delignification of steam-pretreated poplar by a bacterial laccase.

    Science.gov (United States)

    Singh, Rahul; Hu, Jinguang; Regner, Matthew R; Round, James W; Ralph, John; Saddler, John N; Eltis, Lindsay D

    2017-02-07

    The recalcitrance of woody biomass, particularly its lignin component, hinders its sustainable transformation to fuels and biomaterials. Although the recent discovery of several bacterial ligninases promises the development of novel biocatalysts, these enzymes have largely been characterized using model substrates: direct evidence for their action on biomass is lacking. Herein, we report the delignification of woody biomass by a small laccase (sLac) from Amycolatopsis sp. 75iv3. Incubation of steam-pretreated poplar (SPP) with sLac enhanced the release of acid-precipitable polymeric lignin (APPL) by ~6-fold, and reduced the amount of acid-soluble lignin by ~15%. NMR spectrometry revealed that the APPL was significantly syringyl-enriched relative to the original material (~16:1 vs. ~3:1), and that sLac preferentially oxidized syringyl units and altered interunit linkage distributions. sLac's substrate preference among monoaryls was also consistent with this observation. In addition, sLac treatment reduced the molar mass of the APPL by over 50%, as determined by gel-permeation chromatography coupled with multi-angle light scattering. Finally, sLac acted synergistically with a commercial cellulase cocktail to increase glucose production from SPP ~8%. Overall, this study establishes the lignolytic activity of sLac on woody biomass and highlights the biocatalytic potential of bacterial enzymes.

  15. A review of biological delignification and detoxification methods for lignocellulosic bioethanol production.

    Science.gov (United States)

    Moreno, Antonio D; Ibarra, David; Alvira, Pablo; Tomás-Pejó, Elia; Ballesteros, Mercedes

    2015-01-01

    Future biorefineries will integrate biomass conversion processes to produce fuels, power, heat and value-added chemicals. Due to its low price and wide distribution, lignocellulosic biomass is expected to play an important role toward this goal. Regarding renewable biofuel production, bioethanol from lignocellulosic feedstocks is considered the most feasible option for fossil fuels replacement since these raw materials do not compete with food or feed crops. In the overall process, lignin, the natural barrier of the lignocellulosic biomass, represents an important limiting factor in biomass digestibility. In order to reduce the recalcitrant structure of lignocellulose, biological pretreatments have been promoted as sustainable and environmentally friendly alternatives to traditional physico-chemical technologies, which are expensive and pollute the environment. These approaches include the use of diverse white-rot fungi and/or ligninolytic enzymes, which disrupt lignin polymers and facilitate the bioconversion of the sugar fraction into ethanol. As there is still no suitable biological pretreatment technology ready to scale up in an industrial context, white-rot fungi and/or ligninolytic enzymes have also been proposed to overcome, in a separated or in situ biodetoxification step, the effect of the inhibitors produced by non-biological pretreatments. The present work reviews the latest studies regarding the application of different microorganisms or enzymes as useful and environmentally friendly delignification and detoxification technologies for lignocellulosic biofuel production. This review also points out the main challenges and possible ways to make these technologies a reality for the bioethanol industry.

  16. Enhanced Delignification of Lignocellulosic Biomass by Recombinant Fungus Phanerochaete chrysosporium Overexpressing Laccases and Peroxidases.

    Science.gov (United States)

    Coconi Linares, Nancy; Fernández, Francisco; Loske, Achim M; Gómez-Lim, Miguel A

    2018-02-27

    Ligninolytic enzyme production and lignin degradation are typically the rate-limiting steps in the biofuel industry. To improve the efficiency of simultaneous bio-delignification and enzyme production, Phanerochaete chrysosporium was transformed by shock wave-induced acoustic cavitation to co-overexpress 3 peroxidases and 1 laccase and test it on the degradation of sugarcane bagasse and wheat bran. Lignin depolymerization was enhanced by up to 25% in the presence of recombinant fungi in comparison with the wild-type strain. Sugar release on lignocellulose was 2- to 6-fold higher by recombinant fungi as compared with the control. Wheat bran ostensibly stimulated the production of ligninolytic enzymes. The highest peroxidase activity from the recombinant strains was 2.6-fold higher, whereas the increase in laccase activity was 4-fold higher in comparison to the control. The improvement of lignin degradation was directly proportional to the highest peroxidase and laccase activity. Because various phenolic compounds released during lignocellulose degradation have proven to be toxic to cells and to inhibit enzyme activity, a significant reduction (over 40%) of the total phenolic content in the samples treated with recombinant strains was observed. To our knowledge, this is the first report that engineering P. chrysosporium enhances biodegradation of lignocellulosic biomass. © 2018 S. Karger AG, Basel.

  17. Modification of pine pulp during oxygen delignification by xylan self-assembly.

    Science.gov (United States)

    Grigoray, Olga; Järnström, Joakim; Heikkilä, Elina; Fardim, Pedro; Heinze, Thomas

    2014-11-04

    Self-assembly is a technique of preparing functional materials based on targeted intermolecular interactions involving different macromolecules. In this work, hardwood xylan was disassembled from wood and birch bleached kraft pulp using pressurized hot water extraction (HWX) and cold alkali extraction (CAX), respectively. The extracted biopolymers were characterized using gas chromatography (GC), size exclusion chromatography (SEC) and Fourier transform infrared spectroscopy (FTIR), and subsequently added into an oxygen delignification reactor containing pine kraft pulp. The assembly of xylan-pulp fiber was characterized using advanced time-of-flight secondary ion mass spectrometry (ToF-SIMS) and imaging. The xylan-pine pulp assembly was not significantly removed during the whole elemental chlorine free bleaching sequence or during low consistency refining. Modified fibers had superior mechanical properties compared to the reference pulp. Our concept can be easily applied in the pulp and paper industry, and it opens new possibilities for the utilization of fully bio-based fibers in new materials. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Study of the delignification of hardwood chips in a pulping process for sugar production.

    Science.gov (United States)

    Llano, Tamara; Rueda, Cristina; Quijorna, Natalia; Blanco, Alain; Coz, Alberto

    2012-12-31

    Spent sulphite liquor is a lignocellulosic residue obtained in the acid sulphite pulping process after the digestion of hardwood chips, and composed mainly by lignosulphonates and hemicelluloses. The aim of this work is to study the main process variables at different digestion conditions: maximum temperature, heating rate, and total SO₂ content, which affect the delignification process of hardwood chips to obtain dissolving pulp and to increase the total amount of fermentable sugars and lignosulphonates presented in this lignocellulosic waste. The best results are 210.5 g/L of lignosulphonates and 47.26 g/L of total monosaccharides obtained at higher temperatures of 1.058T and 1.072T, low heating rates of 0.334R and 0.285R, and total SO₂ content of 6.20%. Furthermore, concentrate-acid hydrolysis of the liquor with sulphuric acid was performed in order to study the evolution of the sugar content and the release of the inhibitors. Temperature, acid concentration, acid/liquor ratio and time were modified, showing that acid/liquid ratio is the most influential variable. Although increase in the content of sugars in neither case, a notable furfural and acetic acid concentration decrease is registered, 97.88% and 36.57% respectively, at 20 °C, 60% (w/w) sulphuric acid and acid/sample ratio of 1/0.1 (v/v). Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Laccase induction by synthetic dyes in Pycnoporus sanguineus and their possible use for sugar cane bagasse delignification.

    Science.gov (United States)

    Hernández, Christian; Farnet Da Silva, Anne-Marie; Ziarelli, Fabio; Perraud-Gaime, Isabelle; Gutiérrez-Rivera, Beatriz; García-Pérez, José Antonio; Alarcón, Enrique

    2017-02-01

    The use of synthetic dyes for laccase induction in vivo has been scarcely explored. We characterized the effect of adding different synthetic dyes to liquid cultures of Pycnoporus sanguineus on laccase production. We found that carminic acid (CA) can induce 722 % and alizarin yellow 317 % more laccase than control does, and they promoted better fungal biomass development in liquid cultures. Aniline blue and crystal violet did not show such positive effect. CA and alizarin yellow were degraded up to 95 % during P. sanguineus culturing (12 days). With this basis, CA was selected as the best inducer and used to evaluate the induction of laccase on solid-state fermentation (SSF), using sugarcane bagasse (SCB) as substrate, in an attempt to reach selective delignification. We found that laccase induction occurred in SSF, and a slight inhibition of cellulase production was observed when CA was added to the substrate; also, a transformation of SCB under SSF was followed by the 13 C cross polarization magic angle spinning (CPMAS) solid-state nuclear magnetic resonance (NMR). Results showed that P. sanguineus can selectively delignify SCB, decreasing aromatic C compounds by 32.67 % in 16 days; O-alkyl C region (polysaccharides) was degraded less than 2 %; delignification values were not correlated with laccase activities. Cellulose-crystallinity index was increased by 27.24 % in absence of CA and 15.94 % when 0.01 mM of CA was added to SCB; this dye also inhibits the production of fungal biomass in SSF (measured as alkyl C gain). We conclude that CA is a good inducer of laccase in liquid media, and that P. sanguineus is a fungus with high potential for biomass delignification.

  20. Delignification of Sawdust White Teak (Gmelina arborea Roxb. by Fungi Phanerochaete chrysosporium Irradiated Gamma Ray

    Directory of Open Access Journals (Sweden)

    Nurhasni Nurhasni

    2016-12-01

    Full Text Available Abstrak Biomassa lignoselulosa yang merupakan limbah pemanenan kayu harus dilakukan proses untuk memisahkan selulosa, hemiselulosa dan lignin sehingga dapat termanfaatkan. Penelitian ini bertujuan untuk mengetahui efektivitas inokulan fungi Phanerochaete chrysosporium iradiasi gamma dan pretreatment kimia terhadap percepatan delignifikasi serbuk kayu jati putih (Gmelina arborea Roxb. sehingga dapat dimanfaatkan dalam proses pulping. Pada penelitian ini dilakukan pretreatment substrat kayu jati putih (Gmelina arborea Roxb. menggunakan larutan NaOH 1% dan H2SO4 1% serta iradiasi gamma Co-60, yang mempunyai daya ionisasi kecil, daya tembus yang tinggi serta Co-60 dapat memancarkan sinar gamma dengan waktu paruh pendek. Penelitian ini dilakukan dalam dua tahap, tahap pertama penentuan dosis optimum iradiasi gamma terhadap fungi Phanerochaete chrysosporium (0 Gy, 200 Gy, 400 Gy, 600 Gy, 800 Gy, dan 1000 Gy dan tahap kedua analisis karakteristik substrat kayu jati putih yang telah di pretreatment dengan metode Solid State Fermentation (SSF selama 21 hari. Hasil penelitian menunjukkan bahwa dosis optimum pemberian iradiasi gamma pada fungi Phanerochaete chrysosporium yaitu pada dosis 600 Gy yang dapat meningkatkan aktivitas enzim lignin peroksidase (LiP sebesar 22.18 U/mL. Proses pretreatment kimia dengan menggunakan H2SO4 1% dapat mempercepat proses biodelignifikasi yang menghasilkan efisiensi degradasi lignin tertinggi yaitu sebesar 25.65%.   Kata kunci: Lignoselulosa, delignifikasi, Solid State Fermentation (SSF, Phanerochaete chrysosporium,iradiasi gamma.   Abstract   Lignocellulose biomass is waste wood harvesting should be a process for separating cellulose, hemicellulose and lignin that can be utilized. This study aims to determine the effectiveness of the inoculant fungi Phanerochaete chrysosphorium gamma irradiation and chemical pretreatment to accelerate delignification powder white teak (Gmelina arborea Roxb.. In this research

  1. Kraft Pulp Bleaching and Delignification by Dikaryons and Monokaryons of Trametes versicolor

    Science.gov (United States)

    Addleman, Katherine; Archibald, Frederick

    1993-01-01

    The ability of 10 dikaryotic and 20 monokaryotic strains of Trametes (Coriolus) versicolor to bleach and delignify hardwood and softwood kraft pulps was assessed. A dikaryon (52P) and two of its mating-compatible monokaryons (52J and 52D) derived via protoplasting were compared. All three regularly bleached hardwood kraft pulp more than 20 brightness points (International Standards Organization) in 5 days and softwood kraft pulp the same amount in 12 days. Delignification (kappa number reduction) by the dikaryon and the monokaryons was similar, but the growth of the monokaryons was slower. Insoluble dark pigments were commonly found in the mycelium, medium, and pulp of the dikaryon only. Laccase and manganese peroxidase (MnP) but not lignin peroxidase activities were secreted during bleaching by all three strains. Their laccase and MnP isozyme patterns were compared on native gels. No segregation of isozyme bands between the monokaryons was found. Hardwood kraft pulp appeared to adsorb several laccase isozyme bands. One MnP isozyme (pI, 3.2) was secreted in the presence of pulp by all three strains, but a second (pI, 4.9) was produced only by 52P. A lower level of soluble MnP activity in one monokaryon (52D) was associated with reduced bleaching ability and a lower level of methanol production. Since monokaryon 52J bleached pulp better than its parent dikaryon 52P, especially per unit of biomass, this genetically simpler monokaryon will be the preferred subject for further genetic manipulation and improvement of fungal pulp biological bleaching. Images PMID:16348851

  2. Chemical and structural changes associated with Cu-catalyzed alkaline-oxidative delignification of hybrid poplar.

    Science.gov (United States)

    Li, Zhenglun; Bansal, Namita; Azarpira, Ali; Bhalla, Aditya; Chen, Charles H; Ralph, John; Hegg, Eric L; Hodge, David B

    2015-01-01

    Alkaline hydrogen peroxide pretreatment catalyzed by Cu(II) 2,2'-bipyridine complexes has previously been determined to substantially improve the enzymatic hydrolysis of woody plants including hybrid poplar as a consequence of moderate delignification. In the present work, cell wall morphological and lignin structural changes were characterized for this pretreatment approach to gain insights into pretreatment outcomes and, specifically, to identify the extent and nature of lignin modification. Through TEM imaging, this catalytic oxidation process was shown to disrupt cell wall layers in hybrid poplar. Cu-containing nanoparticles, primarily in the Cu(I) oxidation state, co-localized with the disrupted regions, providing indirect evidence of catalytic activity whereby soluble Cu(II) complexes are reduced and precipitated during pretreatment. The concentration of alkali-soluble polymeric and oligomeric lignin was substantially higher for the Cu-catalyzed oxidative pretreatment. This alkali-soluble lignin content increased with time during the catalytic oxidation process, although the molecular weight distributions were unaltered. Yields of aromatic monomers (including phenolic acids and aldehydes) were found to be less than 0.2 % (wt/wt) on lignin. Oxidation of the benzylic alcohol in the lignin side-chain was evident in NMR spectra of the solubilized lignin, whereas minimal changes were observed for the pretreatment-insoluble lignin. These results provide indirect evidence for catalytic activity within the cell wall. The low yields of lignin-derived aromatic monomers, together with the detailed characterization of the pretreatment-soluble and pretreatment-insoluble lignins, indicate that the majority of both lignin pools remained relatively unmodified. As such, the lignins resulting from this process retain features closely resembling native lignins and may, therefore, be amenable to subsequent valorization.

  3. Biological pretreatment of lignocellulosic substrates for enhanced delignification and enzymatic digestibility.

    Science.gov (United States)

    Saritha, M; Arora, Anju; Lata

    2012-06-01

    Sheer enormity of lignocellulosics makes them potential feedstock for biofuel production but, their conversion into fermentable sugars is a major hurdle. They have to be pretreated physically, chemically, or biologically to be used by fermenting organisms for production of ethanol. Each lignocellulosic substrate is a complex mix of cellulose, hemicellulose and lignin, bound in a matrix. While cellulose and hemicellulose yield fermentable sugars, lignin is the most recalcitrant polymer, consisting of phenyl-propanoid units. Many microorganisms in nature are able to attack and degrade lignin, thus making access to cellulose easy. Such organisms are abundantly found in forest leaf litter/composts and especially include the wood rotting fungi, actinomycetes and bacteria. These microorganisms possess enzyme systems to attack, depolymerize and degrade the polymers in lignocellulosic substrates. Current pretreatment research is targeted towards developing processes which are mild, economical and environment friendly facilitating subsequent saccharification of cellulose and its fermentation to ethanol. Besides being the critical step, pretreatment is also cost intensive. Biological treatments with white rot fungi and Streptomyces have been studied for delignification of pulp, increasing digestibility of lignocellulosics for animal feed and for bioremediation of paper mill effluents. Such lignocellulolytic organisms can prove extremely useful in production of bioethanol when used for removal of lignin from lignocellulosic substrate and also for cellulase production. Our studies on treatment of hardwood and softwood residues with Streptomyces griseus isolated from leaf litter showed that it enhanced the mild alkaline solubilisation of lignins and also produced high levels of the cellulase complex when growing on wood substrates. Lignin loss (Klason lignin) observed was 10.5 and 23.5% in case of soft wood and hard wood, respectively. Thus, biological pretreatment process for

  4. Improved production and characterization of a highly stable laccase from the halophilic bacterium Chromohalobacter salexigens for the efficient delignification of almond shell bio-waste.

    Science.gov (United States)

    Jafari, Nasrin; Rezaei, Shahla; Rezaie, Rezvan; Dilmaghani, Haleh; Khoshayand, Mohammad Reza; Faramarzi, Mohammad Ali

    2017-12-01

    Extremozymes have gained importance for their ability to efficiently develop the processes in rigorous industrial conditions with incidence in the recycling of especially robust natural wastes. The production of an extracellular laccase from the halophilic bacterium Chromohalobacter salexigens aided for the bio-delignification of almond shell was optimized using response surface methodology followed by one-factor-at-a-time, resulting in an 80-fold increase in the enzyme yield. Out of 10 different medium components, CuSO 4 , ZnSO 4 , glucose, and urea were shown to have the greatest effects on the laccase production. The crude laccase was surprisingly stable against the various solvents, salts, chemicals, pH ranges, and temperatures, and it exhibited a high catalytic efficiency to a wide range of phenolic and non-phenolic substrates. Laccase reduced the kappa number of the lignin of almond shell by approximately 27% without the aid of a mediator, and the delignification efficiency strengthened by up to 58% reduction in kappa number in the used harsh conditions. Due to the high potential of the enzyme in delignification, specifically under extreme conditions, laccase from C. salexigens can be considered as an ideal alternative for chemical treatment methods in cellulose fibres extraction of lignocellulosic bio-wastes or delignification of the lignin and lignin-derived industrial wastes. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Statistical Optimization of Laccase Production and Delignification of Sugarcane Bagasse by Pleurotus ostreatus in Solid-State Fermentation

    Science.gov (United States)

    Karp, Susan Grace; Faraco, Vincenza; Amore, Antonella; Letti, Luiz Alberto Junior; Thomaz Soccol, Vanete; Soccol, Carlos Ricardo

    2015-01-01

    Laccases are oxidative enzymes related to the degradation of phenolic compounds, including lignin units, with concomitant reduction of oxygen to water. Delignification is a necessary pretreatment step in the process of converting plant biomass into fermentable sugars. The objective of this work was to optimize the production of laccases and to evaluate the delignification of sugarcane bagasse by Pleurotus ostreatus in solid-state fermentation. Among eight variables (pH, water activity, temperature, and concentrations of CuSO4, (NH4)2SO4, KH2PO4, asparagine, and yeast extract), copper sulfate and ammonium sulfate concentrations were demonstrated to significantly influence laccase production. The replacement of ammonium sulfate by yeast extract and the addition of ferulic acid as inducer provided increases of 5.7- and 2.0-fold, respectively, in laccase activity. Optimization of laccase production as a function of yeast extract, copper sulfate, and ferulic acid concentrations was performed by response surface methodology and optimal concentrations were 6.4 g/L, 172.6 μM, and 1.86 mM, respectively. Experimentally, the maximum laccase activity of 151.6 U/g was produced at the 5th day of solid-state fermentation. Lignin content in sugarcane bagasse was reduced from 31.89% to 26.36% after 5 days and to 20.79% after 15 days by the biological treatment of solid-state fermentation. PMID:26180784

  6. Mass balance of pilot-scale pretreatment of sugarcane bagasse by steam explosion followed by alkaline delignification.

    Science.gov (United States)

    Rocha, George J M; Martín, Carlos; da Silva, Vinícius F N; Gómez, Edgardo O; Gonçalves, Adilson R

    2012-05-01

    Five pilot-scale steam explosion pretreatments of sugarcane bagasse followed by alkaline delignification were explored. The solubilised lignin was precipitated with 98% sulphuric acid. Most of the pentosan (82.6%), and the acetyl group fractions were solubilised during pretreatment, while 90.2% of cellulose and 87.0% lignin were recovered in the solid fraction. Approximately 91% of the lignin and 72.5% of the pentosans contained in the steam-exploded solids were solubilised by delignification, resulting in a pulp with almost 90% of cellulose. The acidification of the black liquors allowed recovery of 48.3% of the lignin contained in the raw material. Around 14% of lignin, 22% of cellulose and 26% of pentosans were lost during the process. In order to increase material recovery, major changes, such as introduction of efficient condensers and the reduction in the number of washing steps, should be done in the process setup. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Statistical Optimization of Laccase Production and Delignification of Sugarcane Bagasse by Pleurotus ostreatus in Solid-State Fermentation.

    Science.gov (United States)

    Karp, Susan Grace; Faraco, Vincenza; Amore, Antonella; Letti, Luiz Alberto Junior; Thomaz Soccol, Vanete; Soccol, Carlos Ricardo

    2015-01-01

    Laccases are oxidative enzymes related to the degradation of phenolic compounds, including lignin units, with concomitant reduction of oxygen to water. Delignification is a necessary pretreatment step in the process of converting plant biomass into fermentable sugars. The objective of this work was to optimize the production of laccases and to evaluate the delignification of sugarcane bagasse by Pleurotus ostreatus in solid-state fermentation. Among eight variables (pH, water activity, temperature, and concentrations of CuSO4, (NH4)2SO4, KH2PO4, asparagine, and yeast extract), copper sulfate and ammonium sulfate concentrations were demonstrated to significantly influence laccase production. The replacement of ammonium sulfate by yeast extract and the addition of ferulic acid as inducer provided increases of 5.7- and 2.0-fold, respectively, in laccase activity. Optimization of laccase production as a function of yeast extract, copper sulfate, and ferulic acid concentrations was performed by response surface methodology and optimal concentrations were 6.4 g/L, 172.6 μM, and 1.86 mM, respectively. Experimentally, the maximum laccase activity of 151.6 U/g was produced at the 5th day of solid-state fermentation. Lignin content in sugarcane bagasse was reduced from 31.89% to 26.36% after 5 days and to 20.79% after 15 days by the biological treatment of solid-state fermentation.

  8. Optimization of a novel sequential alkalic and metal salt pretreatment for enhanced delignification and enzymatic saccharification of corn cobs.

    Science.gov (United States)

    Sewsynker-Sukai, Yeshona; Gueguim Kana, E B

    2017-11-01

    This study presents a sequential sodium phosphate dodecahydrate (Na 3 PO 4 ·12H 2 O) and zinc chloride (ZnCl 2 ) pretreatment to enhance delignification and enzymatic saccharification of corn cobs. The effects of process parameters of Na 3 PO 4 ·12H 2 O concentration (5-15%), ZnCl 2 concentration (1-5%) and solid to liquid ratio (5-15%) on reducing sugar yield from corn cobs were investigated. The sequential pretreatment model was developed and optimized with a high coefficient of determination value (0.94). Maximum reducing sugar yield of 1.10±0.01g/g was obtained with 14.02% Na 3 PO 4 ·12H 2 O, 3.65% ZnCl 2 and 5% solid to liquid ratio. Scanning electron microscopy (SEM) and Fourier Transform Infrared analysis (FTIR) showed major lignocellulosic structural changes after the optimized sequential pretreatment with 63.61% delignification. In addition, a 10-fold increase in the sugar yield was observed compared to previous reports on the same substrate. This sequential pretreatment strategy was efficient for enhancing enzymatic saccharification of corn cobs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Understanding pulp delignification by laccase-mediator systems through isolation and characterization of lignin-carbohydrate complexes.

    Science.gov (United States)

    Du, Xueyu; Li, Jiebing; Gellerstedt, Göran; Rencoret, Jorge; Del Río, José C; Martínez, Angel T; Gutiérrez, Ana

    2013-09-09

    The effects and mechanism of pulp delignification by laccases in the presence of redox mediators have been investigated on unbleached eucalyptus kraft pulp treated with laccases from Pycnoporus cinnabarinus (PcL) and Myceliophthora thermophila (MtL) and 1-hydroxybenzotriazole (HBT) and methyl syringate (MeS) as mediators, respectively. Determination of the corrected κ number in eucalyptus pulps after the enzymatic treatments revealed that the PcL-HBT system exhibited a more remarkable delignification effect than the MtL-MeS system. To obtain further insight, lignin-carbohydrate complexes were fractionated and subsequently characterized by nuclear magnetic resonance, thioacidolysis (followed by gas chromatography and size exclusion chromatography), and pyrolysis-gas chromatography-mass spectrometry (pyrolysis-GC-MS) analyses before and after the enzymatic treatments and their controls. We can conclude that the laccase-mediator treatments altered the lignin structures in such a way that more lignin was recovered in the xylan-lignin fractions, as shown by Klason lignin estimation, with smaller amounts of both syringyl (S) and guaiacyl (G) uncondensed units, as shown by thioacidolysis and gas chromatography, especially after the PcL-HBT treatment. The laccase-mediator treatment produced oxidation at Cα and cleavage of Cα and Cβ bonds in pulp lignin, as shown by pyrolysis-GC-MS. The general mechanism of residual lignin degradation in the pulp by laccase-mediator treatments is discussed in light of the results obtained.

  10. Effect of different pretreatments on delignification pattern and enzymatic hydrolysability of miscanthus, oil palm biomass and typha grass.

    Science.gov (United States)

    Timilsena, Yakindra Prasad; Abeywickrama, Chandana Janaka; Rakshit, Sudip Kumar; Brosse, Nicolas

    2013-05-01

    Cumulative pretreatments methods were evaluated for delignification ability and enzymatic digestibility using miscanthus (M×G), empty palm fruit bunch (EFB) and typha grass as feedstocks. Despite their close chemical composition, the three feedstocks unveiled quite different behavior under the same condition of pretreatment. Characterization of ethanol organosol lignins extracted from the three feedstocks by (13)C NMR and FTIR revealed information concerning S/G/H ratios which was important to rationalize the differences among the feedstock behavior. The S/G/H ratios for MxG, EFB and typha, were established to levels of ~52/44/4, ~68/30/2 and ~46/27/27 respectively. The xylans hydrolytic susceptibility were a major cause of difference in behavior of feedstock during the pretreatment process. The influence of the presence of naphthol during autohydrolysis on the delignification ability was studied. A good relationship was observed between S+H/G ratio and the scavenging effect of naphthol. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Meteorological Summaries

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multi-year summaries of one or more meteorological elements at a station or in a state. Primarily includes Form 1078, a United States Weather Bureau form designed...

  12. Survey Summary

    Data.gov (United States)

    U.S. Department of Health & Human Services — Nursing home summary information for the Health and Fire Safety Inspections currently listed on Nursing Home Compare, including dates of the three most recent...

  13. Combination of enzymatic hydrolysis and ethanol organosolv pretreatments: effect on lignin structures, delignification yields and cellulose-to-glucose conversion.

    Science.gov (United States)

    Obama, Patrick; Ricochon, Guillaume; Muniglia, Lionel; Brosse, Nicolas

    2012-05-01

    Enzymatic pre-hydrolysis using the industrial enzymatic cocktail Cellulyve® was assessed as a first step in a pretreatment process of Miscanthus biomass involving an aqueous-ethanol organosolv treatment. (13)C and (31)P Nuclear Magnetic Resonance and size exclusion chromatography were used to analyze the cellulose and lignin before and after treatment. It was demonstrated that despite a very low impact on the fibre structure (observed by Scanning Electron Microscopy) and composition (in terms of sugars and polyphenolics content), the enzymatic pre-treatment disrupted the lignocellulosic matrix to a considerable extend. This weakening permitted enhanced removal of lignin during organosolv pulping and increased hydrolysability of the residual cellulosic pulp for the production of monomeric glucose. Using this combined treatment, a delignification yield of 93% and an enzymatic cellulose-to-glucose conversion of 75% were obtained. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Reduction of enzyme dosage by oxygen delignification and mechanical refining for enzymatic hydrolysis of green liquor-pretreated hardwood.

    Science.gov (United States)

    Koo, Bon-Wook; Treasure, Trevor H; Jameel, Hasan; Phillips, Richard B; Chang, Hou-Min; Park, Sunkyu

    2011-10-01

    In this study, a strategy to reduce enzyme dosage is evaluated by applying two post-treatments, oxygen delignification and mechanical refining. The sugar conversion for GL12 substrates was increased from 51.5% to 77.9% with post-treatments at the enzyme dosage of 10 FPU. When the amount of enzyme was reduced to 5 FPU with post-treatments, the conversion of 71.8% was obtained, which was significant higher than the conversion without any post-treatment using 10 FPU (51.5%). This clearly demonstrates the benefit of post-treatments that allows more than 50% of enzyme reduction at the same level of enzymatic conversion. Enzyme-accessible surface area and pore volume were evaluated by Simons' staining and DSC thermoporometry methods, and strong correlations were found with the sugar conversion.

  15. A comparative study of the biomass properties of Erianthus and sugarcane: lignocellulose structure, alkaline delignification rate, and enzymatic saccharification efficiency.

    Science.gov (United States)

    Miyamoto, Takuji; Yamamura, Masaomi; Tobimatsu, Yuki; Suzuki, Shiro; Kojima, Miho; Takabe, Keiji; Terajima, Yoshifumi; Mihashi, Asako; Kobayashi, Yoshinori; Umezawa, Toshiaki

    2018-03-20

    A comprehensive understanding of the structure and properties of gramineous lignocelluloses is needed to facilitate their uses in biorefinery. In this study, lignocelluloses from fractionated internode tissues of two taxonomically close species, Erianthus arundinaceus and sugarcane (Saccharum spp.), were characterized. Our analyses determined that syringyl (S) lignins were predominant over guaiacyl (G) or p-hydroxyphenyl (H) lignins in sugarcane tissues; on the other hand, S lignin levels were similar to those of G lignin in Erianthus tissues. In addition, tricin units were detected in sugarcane tissues, but not in Erianthus tissues. Distributions of lignin inter-monomeric linkage types were also different in Erianthus and sugarcane tissues. Alkaline treatment removed lignins from sugarcane tissues more efficiently than Erianthus tissues, resulting in a higher enzymatic digestibility of sugarcane tissues compared with Erianthus tissues. Our data indicate that Erianthus biomass displayed resistance to alkaline delignification and enzymatic digestion.

  16. Lignin Peroxidase Activity Is Not Important in Biological Bleaching and Delignification of Unbleached Kraft Pulp by Trametes versicolor

    Science.gov (United States)

    Archibald, Frederick S.

    1992-01-01

    The discovery in 1983 of fungal lignin peroxidases able to catalyze the oxidation of nonphenolic aromatic lignin model compounds and release some CO2 from lignin has been seen as a major advance in understanding how fungi degrade lignin. Recently, the fungus Trametes versicolor was shown to be capable of substantial decolorization and delignification of unbleached industrial kraft pulps over 2 to 5 days. The role, if any, of lignin peroxidase in this biobleaching was therefore examined. Several different assays indicated that T. versicolor can produce and secrete peroxidase proteins, but only under certain culture conditions. However, work employing a new lignin peroxidase inhibitor (metavanadate ions) and a new lignin peroxidase assay using the dye azure B indicated that secreted lignin peroxidases do not play a role in the T. versicolor pulp-bleaching system. Oxidative activity capable of degrading 2-keto-4-methiolbutyric acid (KMB) appeared unique to ligninolytic fungi and always accompanied pulp biobleaching. PMID:16348775

  17. Summary Lecture

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... This summary lecture makes no attempt to summarize what was actually said at the meeting, since this is well covered by the other contributors. Instead I have structured my presentation in three parts: First I try to demonstrate why the Sun is unique by comparing it with laboratory plasmas. This is followed ...

  18. Conference summaries

    International Nuclear Information System (INIS)

    1986-01-01

    This volume contains conference summaries of the international conference on radioactive waste management of the Canadian Nuclear Society. Topics of discussion include: storage and disposal; hydrogeology and geochemistry; transportation; buffers and backfill; public attitudes; tailings; site investigations and geomechanics; concrete; economics; licensing; matrix materials and container design; durability of fuel; biosphere modelling; radioactive waste processing; and, future options

  19. Research Summaries

    Science.gov (United States)

    Brock, Stephen E., Ed.

    2010-01-01

    This column features summaries of research articles from 3 recent crisis management publications. The first, "School Shootings and Counselor Leadership: Four Lessons from the Field" summarized by Kristi Fenning, was conducted as the result of the increased demand for trained crisis personnel on school campuses. Survey participants were…

  20. Carbon dioxide as chemical feedstock

    National Research Council Canada - National Science Library

    Aresta, M

    2010-01-01

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

  1. Conference summaries

    International Nuclear Information System (INIS)

    1987-01-01

    This volume contains summaries of 28 papers presented at the 27. conference of the Canadian Nuclear Association. These papers discuss the general situation of the Canadian nuclear industry and the CANDU reactor; dialogue with the public; the International Atomic Energy Agency; and economic goals and operating lessons. It also contains summaries of 70 papers presented at the 8. conference of the Canadian Nuclear Society, which discuss plant life extension; safety and the environment; reactor physics; thermalhydraulics; risk assessment; the CANDU spacer location and repositioning project; CANDU operations; safety research after Chernobyl; fuel channels; and nuclear technology developments. The individual papers are also available in INIS-mf--13673 (CNA), and INIS-mf--12909 (CNS). (L.L.)

  2. Conference Summary

    International Nuclear Information System (INIS)

    Tinkham, M.

    1991-01-01

    This summary will begin with short remarks, trying to recall some of the spirit of the presentations of each of the speakers during the first day, with no attempt at detail or completeness, given the need for a 20:1 compression relative to the original talk. The author hopes these idiosyncratic recollections do not infuriate the speakers too much. Since the speakers on the second day presented such interlocking topics, he simply tries to present some sort of consensus report, to which he adds some comments of his own. The two talks preceding this Summary on the final day dealt with the prospects for applications; since he had no chance to attempt to prepare a proper report on these, he says only a few words about those presentations

  3. Conference summaries

    International Nuclear Information System (INIS)

    1991-01-01

    This volume contains conference summaries for the 31. annual conference of the Canadian Nuclear Association and the 12. annual conference of the Canadian Nuclear Society. Topics of discussion include: reactor physics; thermalhydraulics; industrial irradiation; computer applications; fuel channel analysis; small reactors; severe accidents; fuel behaviour under accident conditions; reactor components, safety related computer software; nuclear fuel management; fuel behaviour and performance; reactor safety; reactor engineering; nuclear waste management; and, uranium mining and processing

  4. Neural network modeling to support an experimental study of the delignification process of sugarcane bagasse after alkaline hydrogen peroxide pre-treatment.

    Science.gov (United States)

    Valim, Isabelle C; Fidalgo, Juliana L G; Rego, Artur S C; Vilani, Cecília; Martins, Ana Rosa F A; Santos, Brunno F

    2017-11-01

    The present study examines the use of Artificial Neural Networks (ANN) as prediction and fault detection tools for the delignification process of sugarcane bagasse via hydrogen peroxide (H 2 O 2 ). Experimental conditions varied from 25 to 45°C for temperature and from 1.5% to 7.5% (v/v) for H 2 O 2 concentrations. Analytical results for the delignification were obtained by Fourier Transform Infrared (FT-IR) analysis and used for the ANN training and testing steps, allowing for the development of ANN models. The condition experimentally identified as the most suitable for the delignification process was of 25°C with 4.5% (v/v) H 2 O 2 , oxidizing 54% of total lignin. An ANN topology was selected for each proposed model, whose performance was evaluated by the correlation coefficient (R 2 ) and error indices (MSE and SSE). The values obtained for R 2 and the error indices indicated good agreements of the theoretical and actual data, of close to 1 and close to 0, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Synergistic effect of delignification and treatment with the ionic liquid 1-ethyl-3-methylimidazolium acetate on enzymatic digestibility of poplar wood.

    Science.gov (United States)

    Wu, Long; Kumagai, Akio; Lee, Seung-Hwan; Endo, Takashi

    2014-06-01

    This study examined the effects of removing key recalcitrance factors by ionic liquid (IL) treatment on the cellulase digestibility of poplar wood. Ground biomass was subjected to chlorite delignification and IL (1-ethyl-3-methylimidazolium acetate) treatment alone or in combination. The compositional and structural features of differentially treated biomass samples and their hydrolysis performance at various cellulase loadings were investigated. IL treatment caused minor compositional changes but drastically decreased cellulose crystallinity; in particular, when administered after delignification, an X-ray diffractogram similar to that of cellulose II polymorph was observed, suggesting that in the absence of lignin, the cellulose was dissolved in the IL and regenerated in water with a polymorphic transformation. The structural changes induced by the combined delignification-IL treatment facilitated the enzymatic hydrolysis of cellulose; the biomass could be fully degraded within 72 h by 4 FPU of cellulase per gram glucan, with cellobiose degradation being the rate-limiting step. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Classification of titanium dioxide

    International Nuclear Information System (INIS)

    Macias B, L.R.; Garcia C, R.M.; Maya M, M.E.; Ita T, A. De; Palacios G, J.

    2002-01-01

    In this work the X-ray diffraction (XRD), Scanning Electron Microscopy (Sem) and the X-ray Dispersive Energy Spectroscopy techniques are used with the purpose to achieve a complete identification of phases and mixture of phases of a crystalline material as titanium dioxide. The problem for solving consists of being able to distinguish a sample of titanium dioxide being different than a titanium dioxide pigment. A standard sample of titanium dioxide with NIST certificate is used, which indicates a purity of 99.74% for the TiO 2 . The following way is recommended to proceed: a)To make an analysis by means of X-ray diffraction technique to the sample of titanium dioxide pigment and on the standard of titanium dioxide waiting not find differences. b) To make a chemical analysis by the X-ray Dispersive Energy Spectroscopy via in a microscope, taking advantage of the high vacuum since it is oxygen which is analysed and if it is concluded that the aluminium oxide appears in a greater proportion to 1% it is established that is a titanium dioxide pigment, but if it is lesser then it will be only titanium dioxide. This type of analysis is an application of the nuclear techniques useful for the tariff classification of merchandise which is considered as of difficult recognition. (Author)

  7. Uranium dioxide pellets

    International Nuclear Information System (INIS)

    Zawidzki, T.W.

    1979-01-01

    Sintered uranium dioxide pellets composed of particles of size > 50 microns suitable for power reactor use are made by incorporating a small amount of sulphur into the uranium dioxide before sintering. The increase in grain size achieved results in an improvement in overall efficiency when such pellets are used in a power reactor. (author)

  8. Summary guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Halsnaes, K.; Painuly, J.P.; Turkson, J.; Meyer, H.J.; Markandya, A.

    1999-09-01

    This document is a summary version of the methodological guidelines for climate change mitigation assessment developed as part of the Global Environment Facility (GEF) project Economics of Greenhouse Gas Limitations; Methodological Guidelines. The objectives of this project have been to develop a methodology, an implementing framework and a reporting system which countries can use in the construction of national climate change mitigation policies and in meeting their future reporting obligations under the FCCC. The methodological framework developed in the Methodological Guidelines covers key economic concepts, scenario building, modelling tools and common assumptions. It was used by several country studies included in the project. (au) 13 refs.

  9. Executive summary

    International Nuclear Information System (INIS)

    1981-02-01

    This paper is an 'executive summary' of work undertaken to review proposals for transport, handling and emplacement of high level radioactive wastes in an underground repository, appropriate to the U.K. context, with particular reference to: waste block size and configuration; self-shielded or partially-shielded block; stages of disposal; transportation within the repository; emplacement in vertical holes or horizontal tunnels; repository access by adit, incline or shaft; and costs. The paper contains a section on general conclusions and recommendations. (U.K.)

  10. Conference summaries

    International Nuclear Information System (INIS)

    1988-01-01

    This volume contains conference summaries of the 28. annual conference of the Canadian Nuclear Association, and the 9. annual conference of the Canadian Nuclear Society. Topics of discussion include: power reactors; fuel cycles; nuclear power and public understanding; future trends; applications of nuclear technology; CANDU reactors; operational enhancements; design of small reactors; accident behaviour in fuel channels; fuel storage and waste management; reactor commissioning/decommissioning; nuclear safety experiments and modelling; the next generation reactors; advances in nuclear engineering education in Canada; safety of small reactors; current position and improvements of fuel channels; current issues in nuclear safety; and radiation applications - medical and industrial

  11. A combined sodium phosphate and sodium sulfide pretreatment for enhanced enzymatic digestibility and delignification of corn stover.

    Science.gov (United States)

    Qing, Qing; Zhou, Linlin; Guo, Qi; Huang, Meizi; He, Yucai; Wang, Liqun; Zhang, Yue

    2016-10-01

    Na3PO4 and Na2S were employed as efficient alkaline catalysts for the pretreatment of corn stover. To systematically obtain optimal conditions, the effects of critical pretreatment parameters including sodium phosphate concentration (1-4%), sulfidity (0-20%), pretreatment temperature (100-120°C), and reaction time (20-60min) on the reducing sugar yield of pretreated substrates were evaluated in a lab-scale using the response surface methodology. Pretreated under the sodium phosphate concentration of 4%, sulfidity of 10%, temperature of 120°C, and reaction time of 40min, the reducing sugar yield and glucose yield of the pretreated corn stover achieved 91.11% and 64.01%, respectively, with a moderate enzyme loading of 30FPU/g substrate. Additionally, a strong correlation (R(2)=0.971 and R(2)=0.954) between the delignification and the reducing sugar yield (or glucose yield) was observed by this pretreatment method. These results evidently support that the combined Na3PO4-Na2S pretreatment is an effective and feasible method for processing lignocellulosic biomass. Copyright © 2016. Published by Elsevier Ltd.

  12. Delignification of Wood Chips and Pulps by Using Natural and Synthetic Porphyrins: Models of Fungal Decay †

    Science.gov (United States)

    Paszczyński, Andrzej; Crawford, Ronald L.; Blanchette, Robert A.

    1988-01-01

    Kraft pulps, prepared from softwoods, and small chips of birch wood were treated with heme and tert-butyl hydroperoxide in aqueous solutions at reflux temperature. Analyses of treated pulps showed decreases in kappa number (a measure of lignin content) from about 36 to less than 2, with concomitant increases in brightness (80% increase in the better samples). Analyses of treated wood chips revealed selective delignification and removal of hemicelluloses. After 48 h of treatment, lignin losses from the wood chips approached 40%, and xylose/mannose (hemicellulose) losses approached 70%, while glucose (cellulose) losses were less than 10%. Examination of delignified chips by transmission electron microscopy showed that the removal of lignin occurred in a manner virtually indistinguishable from that seen after decay by white rot fungi. Various metalloporphyrins, which act as biomimetic catalysts, were compared to horseradish peroxidase and fungal manganese peroxidase in their abilities to oxidize syringaldazine in an organic solvent, dioxane. The metalloporphyrins and peroxidases behaved similarly, and it appeared that the activities of the peroxidases resulted from the extraction of heme into the organic phase, rather than from the activities of the enzymes themselves. We concluded that heme-tert-butyl hydroperoxide systems in the absence of a protein carrier mimic the decay of lignified tissues by white rot fungi. Images PMID:16347540

  13. Biological delignification of paddy straw and Parthenium sp. using a novel micromycete Myrothecium roridum LG7 for enhanced saccharification.

    Science.gov (United States)

    Tiwari, Rameshwar; Rana, Sarika; Singh, Surender; Arora, Anju; Kaushik, Rajeev; Agrawal, Ved Varun; Saxena, Anil Kumar; Nain, Lata

    2013-05-01

    A new lignolytic micromycete fungus Myrothecium roridum LG7 was isolated and selected for biological delignification of agro residue-paddy straw and herbaceous weed Parthenium sp. Physical and chemical modifications in the biomass following pretreatment with M. roridum LG7 for 7 days in term of structural modification and lignin removal, changes in lignin skeleton, and alteration of cellulose crystallinity was observed through SEM-EDXA, FTIR and XRD analysis, respectively. Colonization of the fungus led to high amount of lignin removal (5.8-6.98mg/gds) from pretreated biomass which could be recovered as a value added product. Enzymatic hydrolysis of M. roridum LG7 pretreated biomass released significantly higher amount of reducing sugars (455.81-509.65 mg/gds) as compared to respective raw biomass within 24h. This study illustrates the promise of M. roridum LG7 for biological pretreatment through structural and chemical alteration of biomass beside creation of alkaline environment which prevent the growth of other contaminants. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Carbon dioxide removal process

    Science.gov (United States)

    Baker, Richard W.; Da Costa, Andre R.; Lokhandwala, Kaaeid A.

    2003-11-18

    A process and apparatus for separating carbon dioxide from gas, especially natural gas, that also contains C.sub.3+ hydrocarbons. The invention uses two or three membrane separation steps, optionally in conjunction with cooling/condensation under pressure, to yield a lighter, sweeter product natural gas stream, and/or a carbon dioxide stream of reinjection quality and/or a natural gas liquids (NGL) stream.

  15. Executive Summary

    International Nuclear Information System (INIS)

    2014-01-01

    Each session of the workshop consisted of a number of presentations followed by a panel discussion moderated by the session Chairs. A summary of each session and subsequent discussion that ensued are provided. Session 1: National approaches for long term interim storage facilities. Seven papers were presented during this session by representatives of research institutes in USA (EPRI) and in Norway (IFE), governmental authorities for the nuclear industry in Finland (STUK) and Slovak Republic (UJD), technical support organizations in Germany (GRS) and France (IRSN) and the public company in charge of waste management in Spain (ENRESA). The papers discussed the national policy, the regulatory framework and the current situation for storage of SF and HLW in various European countries (Germany, Spain, Finland, Norway and Slovak Republic). The main activities the EPRI is undertaking to establish the technical bases for extended (long-term) storage and the IRSN's definition of the safety principles and objectives for new storage facilities regarding long-term storage are also discussed. Session 2: Safety requirements, regulatory framework and implementation issues. Eleven papers were presented during this session by representatives from international groups (the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency (NEA)), representatives of regulatory bodies from the United States (Nuclear Regulatory Commission) and Germany (Bundesamt fuer Strahlenschutz (BfS)), German Federal Institute for Materials Research and Testing (BAM), operators from the United Kingdom (Sellafield Limited, UK) and France (EDF), vendors (AREVA), and representatives of TSOs in Germany (TUV and Oko-Institut). Session 3: Technical issues and operational experience, needs for R and D. This session was chaired by Karl Wasinger (AREVA, Germany) and Fumihisa Nagase (JAEA, Japan). Ten papers were presented during this session by representatives of research institutes of Japan (CRIEPI

  16. Management summary

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    A most pressing problem in many environmental assessments is determining the extent of contamination to the biosphere resulting from a given activity. This could result from the planned or accidental release of a contaminant to the environment and its subsequent transport through air, water, or the food chain. In either case, three critical questions need to be raised in the environmental assessment of the problem: Where are the contaminants; When will they arrive at a specific location; How much of the contaminant will be at the point of uptake. The location of the contaminant is important, since a contaminant isolated from man both now and in the future may represent little hazard, even in rather large quantities. Under other conditions, small amounts of contaminants arriving at critical locations over a short period may involve severe hazard. The problem of location is simplified by concentrating on those places where the contaminants will interface with the biosphere. Applications in evaluating the consequences of ground water contamination are discussed. Environmental consequences or impacts are most effectively and efficiently communicated by: Blending extensive technical results and reducing them to simple summary relationships, i.e., the arrival distributions; focusing on the arrival distributions as the central theme of communication efforts; and determining quantitative consequences or impacts to the biosphere through use of the arrival distributions. Appropriately applied, these principles can reduce a voluminous impact statement on subsurface pollution to a few pages that are directly useful to decision-makers and the public

  17. Theory summary

    International Nuclear Information System (INIS)

    Tang, W.M.

    2001-01-01

    This is a summary of the advances in magnetic fusion energy theory research presented at the 17th International Atomic Energy Agency Fusion Energy Conference from 19 24 October, 1998 in Yokohama, Japan. Theory and simulation results from this conference provided encouraging evidence of significant progress in understanding the physics of thermonuclear plasmas. Indeed, the grand challenge for this field is to acquire the basic understanding that can readily enable the innovations which would make fusion energy practical. In this sense, research in fusion energy is increasingly able to be categorized as fitting well the 'Pasteur's Quadrant' paradigm, where the research strongly couples basic science ('Bohr's Quadrant') to technological impact ('Edison's Quadrant'). As supported by some of the work presented at this conference, this trend will be further enhanced by advanced simulations. Eventually, realistic three-dimensional modeling capabilities, when properly combined with rapid and complete data interpretation of results from both experiments and simulations, can contribute to a greatly enhanced cycle of understanding and innovation. Plasma science theory and simulation have provided reliable foundations for this improved modeling capability, and the exciting advances in high-performance computational resources have further accelerated progress. There were 68 papers presented at this conference in the area of magnetic fusion energy theory

  18. Session summaries

    International Nuclear Information System (INIS)

    Sudo, Y.

    2002-01-01

    In the summary session, possible international activities in the field of basic studies on high-temperature engineering were discussed within the framework of the OECD/NEA Nuclear Science Committee (NSC). It was recommended to include topics relevant to fission-product behaviour and safety issues of HTGR in next meeting, in addition to the topics discussed in this meeting. The chairperson of the last session summarised the recommendations to be presented to the NSC into the following five topics as possible international activities: - Basic studies on behaviour of irradiated graphite/carbon and ceramic materials including their composites under both operation and storage conditions. - Development of in-core material characterisation and instrumentation methods. - Improvement in material properties through high-temperature irradiation. - Basic studies on HTGR fuel fabrication and performance including fission-product release. - Basic studies on safety issues of HTGR. It was also recommended that a further information exchange meeting focused on the organisation of the interactive collaboration activity with regard to the above topics be planned in 2003, tentatively in Oarai, Japan. (author)

  19. A utilização de perácidos na deslignificação e no branqueamento de polpas celulósicas The use of peracids in delignification and cellulose pulp bleaching

    Directory of Open Access Journals (Sweden)

    Lilian Borges Brasileiro

    2001-12-01

    Full Text Available Peracids are strong oxidant species and their use is being largely studied in the delignification and cellulose pulp bleaching. Some of them has already an industrial application, specially in non-conventional bleaching sequences like ECF (Elemental chlorine free and TCF (Totally chlorine free. This review presents the main aspects of the structure, properties, preparation and reaction of peracids (peracetic acid, peroxymonosulfuric acid and their mixture with lignin, specially for peracetic acid. Information about bleaching and delignification of wood pulps with peracids and the factors affecting its efficiency are also presented.

  20. Physicochemical characterization, modelling and optimization of ultrasono-assisted acid pretreatment of two Pennisetum sp. using Taguchi and artificial neural networking for enhanced delignification.

    Science.gov (United States)

    Mohapatra, Sonali; Dandapat, Snigdha Jyotsna; Thatoi, Hrudayanath

    2017-02-01

    Acid as well as ultrasono-assisted acid pretreatment of lignocellulosic biomass of two Pennisetum sp.; Denanath grass (DG) and Hybrid Napier grass (HNG) have been investigated for enhanced delignification and maximum exposure of cellulose for production of bioethanol. Screening of pretreatment with different acids such as H 2 SO 4 , HCl, H 3 PO 4 and H 2 NO 3 were optimized for different temperature, soaking time and acid concentrations using Taguchi orthogonal array and the data obtained were statistically validated using artificial neural networking. HCl was found to be the most effective acid for pretreatment of both the Pennisetum sp. The optimized conditions of HCl pretreatment were acid concentration of 1% and 1.5%, soaking time 130 and 50 min and temperature 121 °C and 110 °C which yielded maximum delignification of 33.0% and 33.8% for DG and HNG respectively. Further ultrosono-assisted HCl pretreatment with a power supply of 100 W, temperature of 353 K, and duty cycle of 70% has resulted in significantly higher delignification of 80.4% and 82.1% for both DG and HNG respectively than that of acid pretreatment. Investigation using SEM, FTIR and autofloresence microscopy for both acid and ultrasono-assisted acid pretreatment lignocellulosic biomass revealed conformational changes of pretreated lignocellulosic biomass with decreased lignin content and increased exposure of cellulose, with greater effectiveness in case of ultrasono assisted acid pretreatment condition. Copyright © 2016. Published by Elsevier Ltd.

  1. Modulus for the coal ash. Summary

    Energy Technology Data Exchange (ETDEWEB)

    Rank, V.

    1944-06-30

    This summary outlined the procedure for obtaining a modulus to determine the effects of varying ash content. This modulus was to indicate the relative amounts of aluminum oxide and silicon dioxide after addition of alkalais or alkaline-earth constituents found in catalysts. The calculation of the modulus was based upon stoichiometric ratios of these oxides to other major components of ash as represented in the major minerals in the ash. The assumptions about the conditions in low- to intermediate-temperature coking included the following: (1) magnesium oxide was found only in biotite, which contained potassium oxide, magnesium oxide, aluminum oxide, silicon dioxide, and water in the respective mole ratios 1:4:2:6:1. (2) Potassium oxide outside of biotite was found only in muscovite, which contained potassium oxide, aluminum oxide, silicon dioxide, and water in the respective mole ratios 1:1:6:2. (3) Sodium oxide was combined only with aluminum oxide and silicon dioxide in the mole ratios 1:1:6. (4) Phosphoric acid was found as aluminum phosphate. (5) Lime was found in anortite, which contained calcium sulfate, calcium carbonate, or calcium oxide combined with aluminum oxide and silicon dioxide in the mole ratios 1:1:2. (6) Aluminum oxide and silicon dioxide existed mainly in the hydrated state with the two of them combined with water in the mole ratios 1:2:2. The completed formula for the modulus was given as M = (aluminum oxide) + (silicon dioxide) - 0.65(magnesium oxide) - 4.90(potassium oxide + sodium oxide) - 3.96(calcium oxide) - 0.72(phosphorous pentoxide), where the parentheses should be filled by numbers in weight units for the respective compounds.

  2. A Simple Method That Uses Differential Staining and Light Microscopy To Assess the Selectivity of Wood Delignification by White Rot Fungi

    Science.gov (United States)

    Srebotnik, Ewald; Messner, Kurt

    1994-01-01

    Cryostat microtome sections of birch wood degraded by white rot fungi were examined by light microscopy after treatment with two stains: astra-blue, which stains cellulose blue only in the absence of lignin, and safranin, which stains lignin regardless of whether cellulose is present. The method provided a simple and reliable screening procedure that distinguishes between fungi that cause decay by selectively removing lignin and those that degrade both cellulose and lignin simultaneously. Moreover, morphological characteristics specific to selective delignification were revealed. Images PMID:16349245

  3. Executive summary

    International Nuclear Information System (INIS)

    2002-01-01

    systems. The scope of the workshop comprised reactor physics, fuel performance and fuel material technology, thermal-hydraulics, core behaviour and fuel cycle of advanced reactors with different types of fuels or fuel lattices. Reactor types considered were water-cooled, high-temperature gas-cooled and fast spectrum reactors as well as hybrid reactors with fast and thermal neutron spectra. The emphasis was on innovative concepts and issues related to the reactor and fuel. The workshop concluded with a wide-ranging panel discussion which considered some difficult questions from which it is hoped that some recommendations for future priorities can be derived. A record of the discussion is included at the end of this summary. (author)

  4. Uranium dioxide preparation

    International Nuclear Information System (INIS)

    Watt, G.W.; Baugh, D.W. Jr.

    1977-01-01

    An actinide dioxide, e.g., uranium dioxide, is prepared by reacting an actinide nitrate or hydrate or tetrahydrofuranate thereof, e.g., uranyl nitrate, a hydrate of uranyl nitrate, or a tetrahydrofuranate of uranyl nitrate with an alkali or alkaline earth metal adduct of a monocyclic or polycyclic hydrocarbon in the presence of an inert organic solvent. Typically, the starting material may be uranyl nitrate dihydrate or uranyl nitrate ditetrahydrofuranate (the latter material is a novel composition of matter) with a reactant such as the sodium adduct of naphthalene in the presence of a solvent such as tetrahydrofuran. The resultant uranium dioxide may be further purified by heating it in the presence of hydrogen. 15 claims

  5. Improvement in rice straw pulp bleaching effluent quality by incorporating oxygen delignification stage prior to elemental chlorine-free bleaching.

    Science.gov (United States)

    Kaur, Daljeet; Bhardwaj, Nishi K; Lohchab, Rajesh Kumar

    2017-10-01

    Environmental degradation by industrial and other developmental activities is alarming for imperative environmental management by process advancements of production. Pulp and paper mills are now focusing on using nonwood-based raw materials to protect forest resources. In present study, rice straw was utilized for pulp production as it is easily and abundantly available as well as rich in carbohydrates (cellulose and hemicelluloses). Soda-anthraquinone method was used for pulp production as it is widely accepted for agro residues. Bleaching process during paper production is the chief source of wastewater generation. The chlorophenolic compounds generated during bleaching are highly toxic, mutagenic, and bioaccumulative in nature. The objectives of study were to use oxygen delignification (ODL) stage prior to elemental chlorine-free (ECF) bleaching to reduce wastewater load and to study its impact on bleached pulp characteristics. ODL stage prior to ECF bleaching improved the optical properties of pulp in comparison to only ECF bleaching. When ODL stage was incorporated prior to bleaching, the tensile index and folding endurance of the pulp were found to be 56.6 ± 1.5 Nm/g and 140, respectively, very high in comparison to ECF alone. A potential reduction of 51, 57, 43, and 53% in BOD 3 , COD, color, and AOX, respectively was observed on adding the ODL stage compared to ECF only. Generation of chlorophenolic compounds was reduced significantly. Incorporation of ODL stage prior to bleaching was found to be highly promising for reducing the toxicity of bleaching effluents and may lead to better management of nearby water resources. Graphical abstract ᅟ.

  6. Summary Record

    International Nuclear Information System (INIS)

    2008-01-01

    (II-3) - Uncertainty analysis of the steady state benchmark. It should be recognized that the purpose of this benchmark is not only to compare currently available macroscopic approaches but above-all to encourage the development of novel next-generation approaches that focus on more microscopic processes. Thus, the benchmark problem includes both macroscopic and microscopic measurement data. In this context, the sub-channel grade void fraction data are regarded as the macroscopic data and the digitized computer graphic images are the microscopic data. The technical topics to be addressed at the workshop include: - Review of the benchmark activities after the 4. Workshop; - Presentation and discussion of summary of comparisons of final submitted results for Exercise 1 of Phase I (I-1); for Exercise 0 of Phase II (II-0); and for Exercise 1 of Phase II (II-1); - Presentation and discussion of comparison of final submitted results for Exercise 2 of Phase I (I-2); - Presentation and discussion of comparison of final submitted results for Exercise 3 of Phase I (I-3); - Presentation and discussion of comparison of final submitted results for Exercise 2 of Phase II (II-2); - Presentation and discussion of preliminary uncertainty results for Exercise 4 of Phase I (I-4); - Presentation and discussion of preliminary uncertainty results for Exercise 3 of Phase II (II-3); - Preparing a special issue in a journal with participants' BFBT papers; - Defining a work plan and schedule outlining actions to advance the two phases of the benchmark activities

  7. Algae Cultivation for Carbon Capture and Utilization Workshop Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-05-01

    The Algae Cultivation for Carbon Capture and Utilization Workshop Summary Report summarizes a workshop hosted by the U.S. Department of Energy's Bioenergy Technologies Office on May 23–24, 2017, in Orlando, Florida. The event gathered stakeholder input through facilitated discussions focused on innovative technologies and business strategies for growing algae on waste carbon dioxide resources.

  8. Production of a lignocellulolytic enzyme system for simultaneous bio-delignification and saccharification of corn stover employing co-culture of fungi.

    Science.gov (United States)

    Ma, Kedong; Ruan, Zhiyong

    2015-01-01

    Aiming at improving the efficiency of transferring corn stover into sugars, an efficient lignocellulolytic enzyme system was developed and investigated by co-cultivation of the Coprinus comatus with Trichoderma reesei in a single bioreactor. The results showed that the lignocellulolytic enzyme activities of the co-culture exceeded that of the monoculture, suggesting synergistic interaction between two fungi. The highest laccase activity from the co-culture was 2.6-fold increase over that of the C. comatus monoculture and reached a peak 3days earlier. The maximum delignification obtained was 66.5% and about 82% of the original polysaccharides were converted into fermentable sugars by simultaneous bio-delignification and saccharification process. Correlation analysis showed that sugar yields were directly proportional to the lignin degradation. Our results suggested that co-fungi cultivation was a valuable technique for corn stover bioconversion, which could produce high efficiency of lignocellulolytic enzyme system as a cheaper alternative to commercial enzymes for industrial utilization. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Immobilization of laccase on modified Fe3O4@SiO2@Kit-6 magnetite nanoparticles for enhanced delignification of olive pomace bio-waste.

    Science.gov (United States)

    Amin, Reza; Khorshidi, Alireza; Shojaei, Abdollah Fallah; Rezaei, Shahla; Faramarzi, Mohammad Ali

    2018-03-19

    Lignocellulose is considered a major source for the production of valuable chemicals. Efficient degradation of lignin as the natural carrier of the lignocellulosic biomass represents a key limiting factor in biomass digestibility. Recently, biological delignification methods have been promoted as sustainable and environmentally friendly alternatives to the traditional technologies. In this study, porous nanocomposite of Fe 3 O 4 @SiO 2 @KIT-6 with magnetic properties was synthesized. The immobilized laccase supported on nanocomposite with enhanced stability in a hydrophobic ionic liquid has been developed for both olive pomace delignification and degradation of phenolic extracts from the pomace. After 6 h incubation, the degradation rate of lignin and phenol by the immobilized laccase was estimated to be 77.3% and 76.5%, respectively. The immobilized laccase retained 70% of its initial degradation ability after 11 successive batch treatments of olive pomace. Furthermore, the immobilized laccase retained >70% of its initial activity after 21 days of storage at room temperature. The obtained results indicated that the immobilized laccase on magnetic mesoporous support together with (1-Butyl-3-methylimidazolium hexafluorophosphate) ([Bmim][PF 6 ]) could potentially provide a promising procedure for an improved enzymatic degradation of lignin and phenol in the related industries. Copyright © 2018. Published by Elsevier B.V.

  10. The effect of direct and counter-current flow-through delignification on enzymatic hydrolysis of wheat straw, and flow limits due to compressibility.

    Science.gov (United States)

    Pihlajaniemi, Ville; Sipponen, Mika Henrikki; Pastinen, Ossi; Nyyssölä, Antti; Laakso, Simo

    2016-12-01

    This article compares the processes for wheat straw lignocellulose fractionation by percolation, counter-current progressing batch percolation and batch reaction at low NaOH-loadings (3-6% of DM). The flow-through processes were found to improve delignification and subsequent enzymatic saccharification, reduce NaOH-consumption and allow reduction of thermal severity, whereas hemicellulose dissolution was unaffected. However, contrary to previous expectations, a counter-current process did not provide additional benefits to regular percolation. The compressibility and flow properties of a straw bed were determined and used for simulation of the packing density profile and dynamic pressure in an industrial scale column. After dissolution of 30% of the straw DM by delignification, a pressure drop above 100 kPa m -1 led to clogging of the flow due to compaction of straw. Accordingly, the maximum applicable feed pressure and volumetric straw throughput was determined as a function of column height, indicating that a 10 m column can be operated at a maximum feed pressure of 530 kPa, corresponding to an operation time of 50 min and a throughput of 163 kg m -3  h -1 . Biotechnol. Bioeng. 2016;113: 2605-2613. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  11. Reactivity of syringyl and guaiacyl lignin units and delignification kinetics in the kraft pulping of Eucalyptus globulus wood using Py-GC-MS/FID.

    Science.gov (United States)

    Lourenço, Ana; Gominho, Jorge; Marques, António Velez; Pereira, Helena

    2012-11-01

    Eucalyptus globulus sapwood and heartwood showed no differences in lignin content (23.0% vs. 23.7%) and composition: syringyl-lignin (17.9% vs. 18.0%) and guaiacyl-lignin (4.8% vs. 5.2%). Delignification kinetics of S- and G-units in heartwood and sapwood was investigated by Py-GC-MS/FID at 130, 150 and 170°C and modeled as double first-order reactions. Reactivity differences between S and G-units were small during the main pulping phase and the higher reactivity of S over G units was better expressed in the later pulping stage. The residual lignin composition in pulps was different from wood or from samples in the initial delignification stages, with more G and H-units. S/G ratio ranged from 3 to 4.5 when pulp residual lignin was higher than 10%, decreasing rapidly to less than 1. The S/H was initially around 20 (until 15% residual lignin), decreasing to 4 when residual lignin was about 3%. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Isolation, one-step affinity purification, and characterization of a polyextremotolerant laccase from the halophilic bacterium Aquisalibacillus elongatus and its application in the delignification of sugar beet pulp.

    Science.gov (United States)

    Rezaei, Shahla; Shahverdi, Ahmad Reza; Faramarzi, Mohammad Ali

    2017-04-01

    The aim of the present work was to study the ability of a halophilic bacterial laccase to efficient delignification in extreme conditions. Here, a highly stable extracellular laccase showing ligninolytic activity from halophilic Aquisalibacillus elongatus is described. The laccase production was strongly influenced by NaCl and CuSO 4 and under optimal conditions reached 4.8UmL -1 . The monomeric enzyme of 75kDa was purified by a synthetic affinity column with 68.2% yield and 99.8-fold purification. The enzyme showed some valuable features viz. stability against a wide range of organic solvents, salts, metals, inhibitors, and surfactants and specificity to a wide spectrum of substrates diverse in structure and redox potential. It retained more than 50% of the original activity at 25-75°C and pH 5.0-10.0. Furthermore, the enzyme was found to be effective in the delignification of sugar beet pulp in an ionic liquid that makes it useful for industrial applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Executive summary

    International Nuclear Information System (INIS)

    2009-01-01

    . These can be grouped into the following categories: the assessment process, licensee actions, regulatory actions. Summaries from the three days of workshop discussions as well as information from the licensee and regulatory responses to two pre-workshop surveys are presented. Also included are highlights from the numerous invited presentations. The conclusions and findings from the extensive group and plenary discussions are summarised too. Supporting material, discussion group presentation slides, slides from the invited presenters, and information/responses to the licensee and regulatory surveys are included in the attached Appendices

  14. Carbon dioxide recycling

    Science.gov (United States)

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

  15. Bench Remarks: Carbon Dioxide.

    Science.gov (United States)

    Bent, Henry A.

    1987-01-01

    Discusses the properties of carbon dioxide in its solid "dry ice" stage. Suggests several demonstrations and experiments that use dry ice to illustrate Avogadro's Law, Boyle's Law, Kinetic-Molecular Theory, and the effects of dry ice in basic solution, in limewater, and in acetone. (TW)

  16. Balancing atmospheric carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

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

    1990-01-01

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

  17. Carbon dioxide dangers demonstration model

    Science.gov (United States)

    Venezky, Dina; Wessells, Stephen

    2010-01-01

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

  18. CARBON DIOXIDE FIXATION.

    Energy Technology Data Exchange (ETDEWEB)

    FUJITA,E.

    2000-01-12

    Solar carbon dioxide fixation offers the possibility of a renewable source of chemicals and fuels in the future. Its realization rests on future advances in the efficiency of solar energy collection and development of suitable catalysts for CO{sub 2} conversion. Recent achievements in the efficiency of solar energy conversion and in catalysis suggest that this approach holds a great deal of promise for contributing to future needs for fuels and chemicals.

  19. Comparison of the efficiency of bacterial and fungal laccases in delignification and detoxification of steam-pretreated lignocellulosic biomass for bioethanol production.

    Science.gov (United States)

    De La Torre, María; Martín-Sampedro, Raquel; Fillat, Úrsula; Eugenio, María E; Blánquez, Alba; Hernández, Manuel; Arias, María E; Ibarra, David

    2017-11-01

    This study evaluates the potential of a bacterial laccase from Streptomyces ipomoeae (SilA) for delignification and detoxification of steam-exploded wheat straw, in comparison with a commercial fungal laccase from Trametes villosa. When alkali extraction followed by SilA laccase treatment was applied to the water insoluble solids fraction, a slight reduction in lignin content was detected, and after a saccharification step, an increase in both glucose and xylose production (16 and 6%, respectively) was observed. These effects were not produced with T. villosa laccase. Concerning to the fermentation process, the treatment of the steam-exploded whole slurry with both laccases produced a decrease in the phenol content by up to 35 and 71% with bacterial and fungal laccases, respectively. The phenols reduction resulted in an improved performance of Saccharomyces cerevisiae during a simultaneous saccharification and fermentation (SSF) process, improving ethanol production rate. This enhancement was more marked with a presaccharification step prior to the SSF process.

  20. Spectrophotometric determination of sulphur dioxide.

    Science.gov (United States)

    Parashar, D C; Raman, V; Singh, M

    1987-01-01

    Sulphur dioxide, an important industrial gas and air pollutant, is usually estimated using mercury salts. The authors have developed a method in which hazardous mercury salts are avoided. Sulphur dioxide is trapped in aqueous morpholine and mixed with the excess of dichromate solution in acidic medium. The hexavalent chromium in dichromate is reduced to trivalent chromium by sulphur dioxide and the excess of hexavalent chromium is determined with diphenylcarbazide which yields a soluble red-violet complex with an absorption maximum at 540 nm. The decrease in the absorbance values of the red-violet complex formed after reduction, when compared to that of a reagent control, is proportional to the concentration of sulphur dioxide used for reduction. Beer's law operates between 0.4 and 4 microg ml(-1) concentration of sulphur dioxide in solution.

  1. Indexing for summary queries

    DEFF Research Database (Denmark)

    Yi, Ke; Wang, Lu; Wei, Zhewei

    2014-01-01

    returned by reporting queries. In this article, we design indexing techniques that allow for extracting a statistical summary of all the records in the query. The summaries we support include frequent items, quantiles, and various sketches, all of which are of central importance in massive data analysis....... Our indexes require linear space and extract a summary with the optimal or near-optimal query cost. We illustrate the efficiency and usefulness of our designs through extensive experiments and a system demonstration....

  2. FEMA Disaster Declarations Summary

    Data.gov (United States)

    Department of Homeland Security — The FEMA Disaster Declarations Summary is a summarized dataset describing all federally declared disasters, starting with the first disaster declaration in 1953,...

  3. Uranium dioxide electrolysis

    Science.gov (United States)

    Willit, James L [Batavia, IL; Ackerman, John P [Prescott, AZ; Williamson, Mark A [Naperville, IL

    2009-12-29

    This is a single stage process for treating spent nuclear fuel from light water reactors. The spent nuclear fuel, uranium oxide, UO.sub.2, is added to a solution of UCl.sub.4 dissolved in molten LiCl. A carbon anode and a metallic cathode is positioned in the molten salt bath. A power source is connected to the electrodes and a voltage greater than or equal to 1.3 volts is applied to the bath. At the anode, the carbon is oxidized to form carbon dioxide and uranium chloride. At the cathode, uranium is electroplated. The uranium chloride at the cathode reacts with more uranium oxide to continue the reaction. The process may also be used with other transuranic oxides and rare earth metal oxides.

  4. Production of uranium dioxide

    International Nuclear Information System (INIS)

    Knudsen, I.E.

    1977-01-01

    A three stage fluidized bed process is described for converting uranium hexafluoride (UF 6 ) to a ceramic-grade uranium dioxide (UO 2 ) powder by first, reacting hydrogen and steam with UF 6 in a first fluidized bed in a temperature range of from about 475 to 600 0 C to form solid intermediate products UO 2 F 2 and U 3 O 8 ; second, reacting hydrogen and steam with the intermediate products in a second fluidized bed at a temperature ranging from about 575 to about 675 0 C to produce a second group of intermediate products including UO 2 F 2 , U 3 O 8 , and UO 2 ; and, third, reacting hydrogen and steam with the second group of intermediate products in a third fluidized bed as a temperature of 575 to 675 0 C to produce ceramic grade UO 2 powder having low residual content of fluorides and other foreign materials. 9 claims, 1 figure

  5. Uranium dioxide pellets

    International Nuclear Information System (INIS)

    Zawidzki, T.W.

    1982-01-01

    A process for the preparation of a sintered, high density, large crystal grain size uranium dioxide pellet is described which involves: (i) reacting a uranyl nitrate of formula UO 2 (NO 3 ) 2 .6H 2 O with a sulphur source, at a temperature of from about 300 deg. C to provide a sulphur-containing uranium trioxide; (ii) reacting the thus-obtained modified uranium trioxide with ammonium nitrate to form an insoluble sulphur-containing ammonium uranate; (iii) neutralizing the thus-formed slurry with ammonium hydroxide to precipitate out as an insoluble ammonium uranate the remaining dissolved uranium; (iv) recovering the thus-formed precipitates in a dry state; (v) reducing the dry precipitate to UO 2 , and forming it into 'green' pellets; and (vi) sintering the pellets in a hydrogen atmosphere at an elevated temperature

  6. Forecasting carbon dioxide emissions.

    Science.gov (United States)

    Zhao, Xiaobing; Du, Ding

    2015-09-01

    This study extends the literature on forecasting carbon dioxide (CO2) emissions by applying the reduced-form econometrics approach of Schmalensee et al. (1998) to a more recent sample period, the post-1997 period. Using the post-1997 period is motivated by the observation that the strengthening pace of global climate policy may have been accelerated since 1997. Based on our parameter estimates, we project 25% reduction in CO2 emissions by 2050 according to an economic and population growth scenario that is more consistent with recent global trends. Our forecasts are conservative due to that we do not have sufficient data to fully take into account recent developments in the global economy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. NFSMI Research Summary

    Science.gov (United States)

    Nettles, Mary Frances

    2014-01-01

    The NFSMI Research Summary is a continuing series of summaries reporting recently completed research and research-based resources funded by the National Food Service Management Institute. The following research studies are summarized in this article: (1) Succession Planning for Management Level Staff in School Nutrition Programs; (2)…

  8. Advanced Analysis Environments - Summary

    International Nuclear Information System (INIS)

    Panacek, Suzanne

    2001-01-01

    This is a summary of the panel discussion on Advanced Analysis Environments. Rene Brun, Tony Johnson, and Lassi Tuura shared their insights about the trends and challenges in analysis environments. This paper contains the initial questions, a summary of the speakers' presentation, and the questions asked by the audience

  9. Supercritical Carbon Dioxide–Based Sterilization of Decellularized Heart Valves

    Directory of Open Access Journals (Sweden)

    Ryan S. Hennessy, MD

    2017-02-01

    Full Text Available Summary: Sterilization of grafts is essential. Supercritical carbon dioxide, electrolyzed water, gamma radiation, ethanol-peracetic acid, and hydrogen peroxide techniques were compared for impact on sterility and mechanical integrity of porcine decellularized aortic valves. Ethanol-peracetic acid– and supercritical carbon dioxide–treated valves were found to be sterile using histology, microbe culture, and electron microscopy assays. The cusp tensile properties of supercritical carbon dioxide–treated valves were higher compared with valves treated with other techniques. Superior sterility and integrity was found in the decellularized valves treated with supercritical carbon dioxide sterilization. This sterilization technique may hold promise for other decellularized soft tissues. Key Words: decellularized, decontamination, heart valve, tensile properties, tissue engineering

  10. Supercritical carbon dioxide-based sterilization of decellularized heart valves

    Science.gov (United States)

    Hennessy, Ryan S.; Jana, Soumen; Tefft, Brandon J.; Helder, Meghana R.; Young, Melissa D.; Hennessy, Rebecca R.; Stoyles, Nicholas J.; Lerman, Amir

    2017-01-01

    Objective The goal of this research project encompasses finding the most efficient and effective method of decellularized tissue sterilization. Background Aortic tissue grafts have been utilized to repair damaged or diseased valves. Although, the tissues for grafting are collected aseptically, it does not eradicate the risk of contamination nor disease transfer. Thus, sterilization of grafts is mandatory. Several techniques have been applied to sterilize grafts; however, each technique shows drawbacks. In this study, we compared several sterilization techniques: supercritical carbon dioxide, electrolyzed water, gamma radiation, ethanol-peracetic acid, and hydrogen peroxide for impact on the sterility and mechanical integrity of porcine decellularized aortic valves. Methods Valve sterility was characterized by histology, microbe culture, and electron microscopy. Uniaxial tensile testing was conducted on the valve cusps along their circumferential orientation to study these sterilization techniques on their integrity. Results Ethanol-peracetic acid and supercritical carbon dioxide treated valves were found to be sterile. The tensile strength of supercritical carbon dioxide treated valves (4.28 ± 0.22 MPa) was higher to those valves treated with electrolyzed water, gamma radiation, ethanol-peracetic acid and hydrogen peroxide (1.02 ± 0.15, 1.25 ± 0.25, 3.53 ± 0.41 and 0.37 ± 0.04 MPa, respectively). Conclusions Superior sterility and integrity were found in the decellularized porcine aortic valves with supercritical carbon dioxide sterilization. This sterilization technique may hold promise for other decellularized soft tissues. Summary Sterilization of grafts is essential. Supercritical carbon dioxide, electrolyzed water, gamma radiation, ethanol-peracetic acid, and hydrogen peroxide techniques were compared for impact on sterility and mechanical integrity of porcine decellularized aortic valves. Ethanol-peracetic acid and supercritical carbon dioxide treated

  11. Recuperative supercritical carbon dioxide cycle

    Science.gov (United States)

    Sonwane, Chandrashekhar; Sprouse, Kenneth M; Subbaraman, Ganesan; O'Connor, George M; Johnson, Gregory A

    2014-11-18

    A power plant includes a closed loop, supercritical carbon dioxide system (CLS-CO.sub.2 system). The CLS-CO.sub.2 system includes a turbine-generator and a high temperature recuperator (HTR) that is arranged to receive expanded carbon dioxide from the turbine-generator. The HTR includes a plurality of heat exchangers that define respective heat exchange areas. At least two of the heat exchangers have different heat exchange areas.

  12. Method for carbon dioxide sequestration

    Science.gov (United States)

    Wang, Yifeng; Bryan, Charles R.; Dewers, Thomas; Heath, Jason E.

    2017-12-05

    A method for geo-sequestration of a carbon dioxide includes selection of a target water-laden geological formation with low-permeability interbeds, providing an injection well into the formation and injecting supercritical carbon dioxide (SC-CO.sub.2) and water or bine into the injection well under conditions of temperature, pressure and density selected to cause the fluid to enter the formation and splinter and/or form immobilized ganglia within the formation.

  13. Summary big data

    CERN Document Server

    2014-01-01

    This work offers a summary of Cukier the book: "Big Data: A Revolution That Will Transform How we Live, Work, and Think" by Viktor Mayer-Schonberg and Kenneth. Summary of the ideas in Viktor Mayer-Schonberg's and Kenneth Cukier's book: " Big Data " explains that big data is where we use huge quantities of data to make better predictions based on the fact we identify patters in the data rather than trying to understand the underlying causes in more detail. This summary highlights that big data will be a source of new economic value and innovation in the future. Moreover, it shows that it will

  14. Biofuels: Project summaries

    Energy Technology Data Exchange (ETDEWEB)

    1994-07-01

    The US DOE, through the Biofuels Systems Division (BSD) is addressing the issues surrounding US vulnerability to petroleum supply. The BSD goal is to develop technologies that are competitive with fossil fuels, in both cost and environmental performance, by the end of the decade. This document contains summaries of ongoing research sponsored by the DOE BSD. A summary sheet is presented for each project funded or in existence during FY 1993. Each summary sheet contains and account of project funding, objectives, accomplishments and current status, and significant publications.

  15. Final summary report

    International Nuclear Information System (INIS)

    Krumhansl, J.A.

    A summary is presented of the topics covered during the period, from 1960 to 1978, of the contract. The general area of the research has been theoretical solid state physics. A list of publications produced during the contract is given

  16. Global Climate Summaries

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Global Hourly Summaries are simple indicators of observational normals which include climatic data summarizations and frequency distributions. These typically...

  17. MSIS State Summary Datamarts

    Data.gov (United States)

    U.S. Department of Health & Human Services — This page provides background needed to take advantage of the capabilities of the MSIS State Summary Datamart. This mart allows the user to develop high-level...

  18. Cancer Information Summaries

    Science.gov (United States)

    Peer-reviewed, evidence-based summaries on topics including adult and pediatric cancer treatment, supportive and palliative care, screening, prevention, genetics, and complementary and alternative medicine. References to published literature are included.

  19. Annual Meteorological Summaries

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Single-year summaries of observations at Weather Bureau and cooperative stations across the United States. Predominantly the single page Form 1066, which includes...

  20. Worldwide Airfield Summary

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Worldwide Airfield Summary contains a selection of climatological data produced by the U.S. Air Force, Air Weather Service. The reports were compiled from dozens...

  1. Summary of blog

    CERN Document Server

    Reader, Capitol

    2013-01-01

    This ebook consists of a summary of the ideas, viewpoints and facts presented by Hugh Hewitt in his book "Blog: Understanding the Information Reformation that's Changing Your World". This summary offers a concise overview of the entire book in less than 30 minutes reading time. However this work does not replace in any case Hugh Hewitt's book.Hewitt argues that blogs have an important potential and he believes that it would be a dreadful mistake to avoid their power.

  2. Site environmental report summary

    International Nuclear Information System (INIS)

    1992-01-01

    In this summary of the Fernald 1992 Site Environmental Report the authors will describe the impact of the Fernald site on man and the environment and provide results from the ongoing Environmental Monitoring Program. Also included is a summary of the data obtained from sampling conducted to determine if the site complies with DOE, US Environmental Protection Agency (USEPA), and Ohio EPA (OEPA) requirements. These requirements are set to protect both man and the environment

  3. 21 CFR 573.940 - Silicon dioxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Silicon dioxide. 573.940 Section 573.940 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... Listing § 573.940 Silicon dioxide. The food additive silicon dioxide may be safely used in animal feed in...

  4. 21 CFR 172.480 - Silicon dioxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Silicon dioxide. 172.480 Section 172.480 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Agents § 172.480 Silicon dioxide. The food additive silicon dioxide may be safely used in food in...

  5. 21 CFR 73.1575 - Titanium dioxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Titanium dioxide. 73.1575 Section 73.1575 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1575 Titanium dioxide. (a) Identity and specifications. (1) The color additive titanium dioxide shall conform in identity and specifications to the requirements...

  6. 40 CFR 180.1195 - Titanium dioxide.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Titanium dioxide. 180.1195 Section 180.1195 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS... Titanium dioxide. Titanium dioxide is exempted from the requirement of a tolerance for residues in or on...

  7. 21 CFR 73.2575 - Titanium dioxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Titanium dioxide. 73.2575 Section 73.2575 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2575 Titanium dioxide. (a) Identity and specifications. The color additive titanium dioxide shall conform in identity and specifications to the requirements...

  8. 21 CFR 73.575 - Titanium dioxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Titanium dioxide. 73.575 Section 73.575 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.575 Titanium dioxide. (a) Identity. (1) The color additive titanium dioxide is synthetically prepared TiO2, free from admixture with other substances. (2) Color...

  9. 21 CFR 73.3126 - Titanium dioxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Titanium dioxide. 73.3126 Section 73.3126 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Medical Devices § 73.3126 Titanium dioxide. (a) Identity and specifications. The color additive titanium dioxide (CAS Reg. No. 13463-67-7), Color Index No. 77891, shall...

  10. Evaluation of a combined brown rot decay-chemical delignification process as a pretreatment for bioethanol production from Pinus radiata wood chips.

    Science.gov (United States)

    Fissore, Antonella; Carrasco, Lissete; Reyes, Pablo; Rodríguez, Jaime; Freer, Juanita; Mendonça, Regis Teixeira

    2010-09-01

    Wood chips of Pinus radiata softwood were biotreated with the brown rot fungus (BRF) Gloeophyllum trabeum for periods from 4 and 12 weeks. Biodegradation by BRF leads to an increase in cellulose depolymerization with increasing incubation time. As a result, the intrinsic viscosity of holocellulose decreased from 1,487 cm(3)/g in control samples to 783 and 600 cm(3)/g in 4- and 12-week decayed wood chips, respectively. Wood weight and glucan losses varied from 6 to 14% and 9 to 21%, respectively. Undecayed and 4-week decayed wood chips were delignified by alkaline (NaOH solution) or organosolv (ethanol/water) processes to produced cellulosic pulps. For both process, pulp yield was 5-10% lower for decayed samples than for control pulps. However, organosolv bio-pulps presented low residual lignin amount and high glucan retention. Chemical pulps and milled wood from undecayed and 4-week decayed wood chips were pre-saccharified with cellulases for 24 h at 50 degrees C followed by simultaneous saccharification and fermentation (SSF) with the yeast Saccharomyces cerevisiae IR2-9a at 40 degrees C for 96 h for bioethanol production. Considering glucan losses during wood decay and conversion yields from chemical pulping and SSF processes, no gains in ethanol production were obtained from the combination of BRF with alkaline delignification; however, the combination of BRF and organosolv processes resulted in a calculated production of 210 mL ethanol/kg wood or 72% of the maximum theoretically possible from that pretreatment, which was the best result obtained in the present study.

  11. Symposium summary and prognosis

    International Nuclear Information System (INIS)

    Bjorken, J.D.

    1975-11-01

    The summary of the symposium on high energy physics experiments includes phenomena at low energies, the foundations of physics (considered to be mainly gravitation and quantum electrodynamics), standards of reference used for interpretation of experimental data, the new physics, particle proliferation, theoretical development, and a prognosis for the future

  12. Summary of cosmology workshop

    Indian Academy of Sciences (India)

    Summary of cosmology workshop consistent with data. Concordant results are also obtained from the formation of large-scale structures in the universe by combining the exquisite measurements of the angular spectrum of CMB anisotropy with recent measurements of the power spectrum of density perturbation from large ...

  13. Summary of discussion

    International Nuclear Information System (INIS)

    2006-01-01

    This document provides summaries of the discussions occurred during the second international workshop on the indemnification of nuclear damage. It concerns the second accident scenario: a fire on board of a ship transporting enriched uranium hexafluoride along the Danube River. (A.L.B.)

  14. Summary of Session III

    International Nuclear Information System (INIS)

    Furman, M.A.

    2002-01-01

    This is a summary of the talks presented in Session III ''Simulations of Electron-Cloud Build Up'' of the Mini-Workshop on Electron-Cloud Simulations for Proton and Positron Beams ECLOUD-02, held at CERN, 15-18 April 2002

  15. Crisis Management Research Summaries

    Science.gov (United States)

    Brock, Stephen E., Ed.; Zhe, Elizabeth; Torem, Chris; Comeaux, Natashia; Dempsey, Allison

    2010-01-01

    This article presents a summary of recent crisis management publications. The first research report summarized, "Predictors of PTSD," was a study of predictor variables for responses to the World Trade Center attack. The second paper, "Effective Mental Health Response to Catastrophic Events," looked at effective responses following Hurricane…

  16. ICPAQGP 2001: Conference summary

    Indian Academy of Sciences (India)

    physics pp. 965–982. ICPAQGP 2001: Conference summary. REINHARD STOCK. University of Frankfurt, August-Euler-Str. 6, D-60486 Frankfurt, Germany ... New data from RHIC and direct photon production results from CERN .... in coupled modes featuring effective masses, our quarks are not really current quarks, the.

  17. Summary of Trends

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Summary of Trends. Optical Ethernet: Direct Ethernet connectivity to businesses through optical fiber. Automation of network infrastructure: Cross-connects for interconnections; Intelligence through software for OA&M. New “data-centric” protection mechanisms ...

  18. Geothermal energy. Program summary

    Energy Technology Data Exchange (ETDEWEB)

    1979-06-01

    Brief descriptions of geothermal projects funded through the Department of Energy during FY 1978 are presented. Each summary gives the project title, contractor name, contract number, funding level, dates, location, and name of the principal investigator, together with project highlights, which provide informaion such as objectives, strategies, and a brief project description. (MHR)

  19. Crisis Management: Research Summaries

    Science.gov (United States)

    Brock, Stephen E., Ed.; Dorman, Sally; Anderson, Luke; McNair, Daniel

    2013-01-01

    This article presents summaries of three studies relevant to school crisis response. The first report, "A Framework for International Crisis Intervention" (Sally Dorman), is a review of how existing crisis intervention models (including the NASP PREPaRE model) have been adapted for international use. The second article, "Responding…

  20. summary writing skills development

    African Journals Online (AJOL)

    In this paper, we outline how translanguaging as a teaching and learning approach promises to develop literacy in both the students' African languages and English. The paper describes a summary skills development teaching approach and its accompanying activities which enable the students to move between isiZulu ...

  1. EFFECTIVE ALKALINE PEROXIDE OXIDATION PRETREATMENT OF SHEA TREE SAWDUST FOR THE PRODUCTION OF BIOFUELS: KINETICS OF DELIGNIFICATION AND ENZYMATIC CONVERSION TO SUGAR AND SUBSEQUENT PRODUCTION OF ETHANOL BY FERMENTATION USING Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    A. O. Ayeni

    Full Text Available Abstract Shea tree sawdust delignification kinetic data during alkaline peroxide pretreatment were investigated at temperatures of 120 °C, 135 °C, and 150 °C. The activation energy during delignification was 76.4 kJ/mol and the Arrhenius constant was calculated as 8.4 x 106 per min. The reducing sugar yield for the treated to the untreated biomass was about 22-fold. Enzymatic hydrolysis conditions studied were; time (72 h and 96 h, substrate concentration (20, 30, 40, and 50 g/L, and enzyme loadings (10, 25, 40, 50 FPU/g dry biomass, which showed the optimum conditions of 96 h, 40 g/L, and 25 FPU/g dry biomass at 45 °C hydrolysis temperature. At the optimized enzymatic hydrolysis conditions, the reducing sugar yield was 416.32 mg equivalent glucose/g treated dry biomass. After 96 h fermentation of treated biomass, the ethanol obtained at 2% effective cellulose loading was 12.73 g/L. Alkaline peroxide oxidation pretreatment and subsequent enzymatic hydrolysis improved the ethanol yield of the biomass.

  2. Extracorporeal carbon dioxide removal in acute exacerbations of chronic obstructive pulmonary disease.

    Science.gov (United States)

    Pettenuzzo, Tommaso; Fan, Eddy; Del Sorbo, Lorenzo

    2018-01-01

    Extracorporeal carbon dioxide removal (ECCO 2 R) has been proposed as an adjunctive intervention to avoid worsening respiratory acidosis, thereby preventing or shortening the duration of invasive mechanical ventilation (IMV) in patients with exacerbation of chronic obstructive pulmonary disease (COPD). This review will present a comprehensive summary of the pathophysiological rationale and clinical evidence of ECCO 2 R in patients suffering from severe COPD exacerbations.

  3. Mineral commodity summaries 2015

    Science.gov (United States)

    ,

    2015-01-01

    Each chapter of the 2015 edition of the U.S. Geological Survey (USGS) Mineral Commodity Summaries (MCS) includes information on events, trends, and issues for each mineral commodity as well as discussions and tabular presentations on domestic industry structure, Government programs, tariffs, 5-year salient statistics, and world production and resources. The MCS is the earliest comprehensive source of 2014 mineral production data for the world. More than 90 individual minerals and materials are covered by two-page synopses.

  4. Summary and closing remarks

    International Nuclear Information System (INIS)

    Hiskes, J.R.

    1996-01-01

    A summary of the topics covered in papers presented at the 1995 Brookhaven joint conference on production, neutralization, and application of negative ion beams is given. The conference topics covered included plasma ion sources, plasma seeding of these sources for increased ion production, beam extraction and transport, computer simulation and design studies, and operation of existing and experimental ion source facilities. Application of the sources to accelerator, tokamak, and thin film deposition are discussed. (AIP) copyright 1996 American Institute of Physics

  5. Blois V: Experimental summary

    International Nuclear Information System (INIS)

    Albrow, M.G.

    1993-09-01

    The author gives a summary talk of the best experimental data given at the Vth Blois Workshop on Elastic and Diffractive Scattering. He addresses the following eight areas in his talk: total and elastic cross sections; single diffractive excitation; electron-proton scattering; di-jets and rapidity gaps; areas of future study; spins and asymmetries; high-transverse momentum and masses at the Tevatron; and disoriented chiral condensates and cosmic radiation

  6. Blois V: Experimental summary

    Energy Technology Data Exchange (ETDEWEB)

    Albrow, M.G.

    1993-09-01

    The author gives a summary talk of the best experimental data given at the Vth Blois Workshop on Elastic and Diffractive Scattering. He addresses the following eight areas in his talk: total and elastic cross sections; single diffractive excitation; electron-proton scattering; di-jets and rapidity gaps; areas of future study; spins and asymmetries; high-transverse momentum and masses at the Tevatron; and disoriented chiral condensates and cosmic radiation.

  7. ULSGEN (Uplink Summary Generator)

    Science.gov (United States)

    Wang, Y.-F.; Schrock, M.; Reeve, T.; Nguyen, K.; Smith, B.

    2014-01-01

    Uplink is an important part of spacecraft operations. Ensuring the accuracy of uplink content is essential to mission success. Before commands are radiated to the spacecraft, the command and sequence must be reviewed and verified by various teams. In most cases, this process requires collecting the command data, reviewing the data during a command conference meeting, and providing physical signatures by designated members of various teams to signify approval of the data. If commands or sequences are disapproved for some reason, the whole process must be restarted. Recording data and decision history is important for traceability reasons. Given that many steps and people are involved in this process, an easily accessible software tool for managing the process is vital to reducing human error which could result in uplinking incorrect data to the spacecraft. An uplink summary generator called ULSGEN was developed to assist this uplink content approval process. ULSGEN generates a web-based summary of uplink file content and provides an online review process. Spacecraft operations personnel view this summary as a final check before actual radiation of the uplink data. .

  8. Carbon dioxide retention in divers

    Energy Technology Data Exchange (ETDEWEB)

    Florio, J.T.; Mackenzie, D.A.R.; McKenzie, R.S. [ARE Physiological Laboratory, Gosport (United Kingdom)

    1998-04-01

    This report summarises the work carried out at the ARE Physiological Laboratory (ARE(PL)) between July 1978 and December 1983. The work was intended to examine the proposition that some divers have a low ventilatory response to carbon dioxide; that this results in a low ventilatory response to exercise with consequent hypercapnia; and that these characteristics put the diver at a greater-than-normal risk by increasing the individual`s susceptibility to oxygen toxicity and to other hazards associated with diving (e.g. nitrogen narcosis, decompression sickness and hypothermia). The specific aims of the project can be summarised as follows: (a) to demonstrate the existence of divers who exhibit the tendency to `retain carbon dioxide` when working in hyperbaric conditions; (b) to define the circumstances under which such individuals are at risk; (c) to assess the magnitude of the risk; and (d) to recommend ways to eliminate or to reduce the risk. (author)

  9. CARBON DIOXIDE AS A FEEDSTOCK.

    Energy Technology Data Exchange (ETDEWEB)

    CREUTZ,C.; FUJITA,E.

    2000-12-09

    This report is an overview on the subject of carbon dioxide as a starting material for organic syntheses of potential commercial interest and the utilization of carbon dioxide as a substrate for fuel production. It draws extensively on literature sources, particularly on the report of a 1999 Workshop on the subject of catalysis in carbon dioxide utilization, but with emphasis on systems of most interest to us. Atmospheric carbon dioxide is an abundant (750 billion tons in atmosphere), but dilute source of carbon (only 0.036 % by volume), so technologies for utilization at the production source are crucial for both sequestration and utilization. Sequestration--such as pumping CO{sub 2} into sea or the earth--is beyond the scope of this report, except where it overlaps utilization, for example in converting CO{sub 2} to polymers. But sequestration dominates current thinking on short term solutions to global warming, as should be clear from reports from this and other workshops. The 3500 million tons estimated to be added to the atmosphere annually at present can be compared to the 110 million tons used to produce chemicals, chiefly urea (75 million tons), salicylic acid, cyclic carbonates and polycarbonates. Increased utilization of CO{sub 2} as a starting material is, however, highly desirable, because it is an inexpensive, non-toxic starting material. There are ongoing efforts to replace phosgene as a starting material. Creation of new materials and markets for them will increase this utilization, producing an increasingly positive, albeit small impact on global CO{sub 2} levels. The other uses of interest are utilization as a solvent and for fuel production and these will be discussed in turn.

  10. Electrodeposition of uranium dioxide films

    International Nuclear Information System (INIS)

    Maya, L.; Gonzalez, B.D.; Lance, M.J.; Holcomb, D.E.

    2004-01-01

    Uranium dioxide films in a hydrated form are electrodeposited unto nickel plates starting with a uranyl nitrate solution in ammonium sulfate. The process is incidental to water splitting which is the dominant electrochemical pathway and as a consequence, the uranium deposition is highly dependent on experimental parameters that require close control such as the pH and concentration of the supporting electrolyte as well as current density, and the cell design. (author)

  11. Manufacture of uranium dioxide powder

    International Nuclear Information System (INIS)

    Becker, M.

    1976-01-01

    Uranium dioxide powder is prepared by the AUC (ammonium uranyl carbonate) method. Supplementing the known process steps, the AUC, after separation from the mother liquor, is washed with an ammonium hydrogen carbonate or an NH 4 OH solution and is subsequently post-treated with a liquid which reduces the surface tension of the residual water in an AUC. Such a liquid is, for instance, alcohol

  12. Carbon dioxide capture and storage

    International Nuclear Information System (INIS)

    Durand, B.

    2011-01-01

    The author first highlights the reasons why storing carbon dioxide in geological formations could be a solution in the struggle against global warming and climate change. Thus, he comments various evolutions and prospective data about carbon emissions or fossil energy consumption as well as various studies performed by international bodies and agencies which show the interest of carbon dioxide storage. He comments the evolution of CO 2 contributions of different industrial sectors and activities, notably in France. He presents the different storage modes and methods which concern different geological formations (saline aquifers, abandoned oil or gas fields, not exploitable coal seams) and different processes (sorption, carbonation). He discusses the risks associated with these storages, the storable quantities, evokes some existing installations in different countries. He comments different ways to capture carbon dioxide (in post-combustion, through oxy-combustion, by pre-combustion) and briefly evokes some existing installations. He evokes the issue of transport, and discusses efficiency and cost aspects, and finally has few words on legal aspects and social acceptability

  13. Internal friction in uranium dioxide

    International Nuclear Information System (INIS)

    Paulin Filho, Pedro Iris

    1979-01-01

    The uranium dioxide inelastic properties were studied measuring internal friction at low frequencies (of the order of 1 Hz). The work was developed in the 160 to 400 deg C temperature range. The effect of stoichiometry variation was studied oxidizing the sample with consequent change of the defect structure originally present in the non-stoichiometric uranium dioxide. The presence of a wide and irregular peak due to oxidation was observed at low temperatures. Activation energy calculations indicated the occurrence of various relaxation processes and assuming the existence of a peak between - 80 and - 70 deg C , the absolute value obtained for the activation energy (0,54 eV) is consistent with the observed values determined at medium and high frequencies for the stress induced reorientation of defects. The microstructure effect on the inelastic properties was studied for stoichiometric uranium dioxide, by varying grain size and porosity. These parameters have influence on the high temperature measurements of internal friction. The internal friction variation for temperatures higher than 340 deg C is thought to be due to grain boundary relaxation phenomena. (author)

  14. Carbon Dioxide Removal via Passive Thermal Approaches

    Science.gov (United States)

    Lawson, Michael; Hanford, Anthony; Conger, Bruce; Anderson, Molly

    2011-01-01

    A paper describes a regenerable approach to separate carbon dioxide from other cabin gases by means of cooling until the carbon dioxide forms carbon dioxide ice on the walls of the physical device. Currently, NASA space vehicles remove carbon dioxide by reaction with lithium hydroxide (LiOH) or by adsorption to an amine, a zeolite, or other sorbent. Use of lithium hydroxide, though reliable and well-understood, requires significant mass for all but the shortest missions in the form of lithium hydroxide pellets, because the reaction of carbon dioxide with lithium hydroxide is essentially irreversible. This approach is regenerable, uses less power than other historical approaches, and it is almost entirely passive, so it is more economical to operate and potentially maintenance- free for long-duration missions. In carbon dioxide removal mode, this approach passes a bone-dry stream of crew cabin atmospheric gas through a metal channel in thermal contact with a radiator. The radiator is pointed to reject thermal loads only to space. Within the channel, the working stream is cooled to the sublimation temperature of carbon dioxide at the prevailing cabin pressure, leading to formation of carbon dioxide ice on the channel walls. After a prescribed time or accumulation of carbon dioxide ice, for regeneration of the device, the channel is closed off from the crew cabin and the carbon dioxide ice is sublimed and either vented to the environment or accumulated for recovery of oxygen in a fully regenerative life support system.

  15. Absorption of carbon dioxide in waste tanks

    International Nuclear Information System (INIS)

    Hobbs, D.T.

    1987-01-01

    Air flow rates and carbon dioxide concentrations of air entering and exiting eight H-Area waste tanks were monitored for a period of one year. The average instanteous concentration of carbon dioxide in air is within the range reported offsite, and therefore is not affect by operation of the coal-fired power plant adjacent to the tank farm. Waste solutions in each of the tanks were observed to be continuously absorbing carbon dioxide. The rate of absorption of carbon dioxide decreased linearly with the pH of the solution. Personnel exposure associated with the routine sampling and analysis of radioactive wastes stored at SRP to determine the levels of corrosion inhibitors in solution could be reduced by monitoring the absorption of carbon dioxide and using the relationship between pH and carbon dioxide absorption to determine the free hydroxide concentration in solution

  16. Carbon dioxide production in animal houses

    DEFF Research Database (Denmark)

    Pedersen, Søren; Blanes-Vidal, Victoria; Joergensen, H.

    2008-01-01

    , when used in full scale animal buildings as basis for estimation of ventilation flow. Based on the data reviewed in this study, we recommend adding 10% carbon dioxide production to the laboratory based carbon dioxide production for animal houses with slatted or solid floors, provided that indoor manure......This article deals with carbon dioxide production from farm animals; more specifically, it addresses the possibilities of using the measured carbon dioxide concentration in animal houses as basis for estimation of ventilation flow (as the ventilation flow is a key parameter of aerial emissions from......C) has often been used. The article shows that the carbon dioxide production per hpu increases with increasing respiration quotient. As the respiration quotient increases with body mass for growing animals, the carbon dioxide production per heat production unit also increases with increased body mass...

  17. Program summary report

    International Nuclear Information System (INIS)

    1978-01-01

    The report provides summary information on all phases of nuclear regulation, and is intended as an information and decision-making tool for mid and upper level management of the Nuclear Regulatory Commission. The report is divided functionally into ten sections: (1) nuclear power plants in the United States; (2) operating nuclear power plants; (3) reactors under construction; (4) operating license applications under NRC review; (5) construction permit applications and special projects under NRC review; (6) ACRS and ASLBP; (7) nuclear materials; (8) standards and regulations; (9) research projects; and (10) foreign reactors

  18. Summary and conclusions

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    Although EPA has the primary administrative role in implementing Title IV of the CAAA, the state public utility commissions and FERC are probably the most important agencies in determining the development and success of an allowance market. The policies and actions they adopt with regard to their jurisdictional utilities to implement the CAAA will profoundly influence the cost of compliance and the extent the market is used by utilities. Special summaries are provided on the topics of beneficial ownership of allowances, ratemaking treatment of allowances, managing uncertainty, and designing general regulatory guidelines. 1 ref

  19. A METHOD OF PREPARING URANIUM DIOXIDE

    Science.gov (United States)

    Scott, F.A.; Mudge, L.K.

    1963-12-17

    A process of purifying raw, in particular plutonium- and fission- products-containing, uranium dioxide is described. The uranium dioxide is dissolved in a molten chloride mixture containing potassium chloride plus sodium, lithium, magnesium, or lead chloride under anhydrous conditions; an electric current and a chlorinating gas are passed through the mixture whereby pure uranium dioxide is deposited on and at the same time partially redissolved from the cathode. (AEC)

  20. Combined effect of sulfur dioxide and carbon dioxide gases on mold fungi

    Energy Technology Data Exchange (ETDEWEB)

    Kochurova, A.I.; Karpova, T.N.

    1974-01-01

    Sulfur dioxide at 0.08% killed Penicillium expansum, Stemphylium macrosporium, and Botrytis cinerea within 24 hours. At 0.2%, it killed P. citrinum, Alternaria tenuis, and Fusarium moniliforme. Sulfur dioxide (at 0.04%) and Sulfur dioxide-carbon dioxide mixtures (at 0.02 and 5% respectively) completely suppressed the growth of P. citrinum, P. expansum, P. rubrum, A. tenuis, S. macrosporium, B. cinerea, and F. moniliforme in laboratory experiments. 1 table.

  1. Intern Summary Reports

    Science.gov (United States)

    2004-01-01

    Topics covered include: Probe Station Antenna Range; LERCIP 2004 Summary; L.E.R.C.I.P. Internship Summary; Hubble Space Telescope Bi-Stem Thermal Shield Analyses; GRABER - the Duct Tape of Space and JIMO Heat Conducting Foam; CDF and PDF Comparison Between Humacao, Puerto Rico and Florida; Development of the On-board Aircraft Network; Development of the Planar Inlet Design and Analysis Process (PINDAP); An Overview of My 2004 Summer Internship [Non-destructive Evaluation]; My Summer Experience as an Administrative Officer Assistant [in the Safety and Assurance Directorate Office]; Programming an Experiment Control System; Reducing the Cation Exchange Capacity of Lithium Clay to Form Better Dispersed; Polymer-Clay Nanocomposites; Feasibility of EB Welded Hastelloy X and Combination of Refractory Metals; My Work in the NASA Glenn History Office and Records Management Office; Education, Technology, and Media: A Peak into My Summer Internship at NASA Glenn Research Center in Cleveland, Ohio; [The Engineering and Technical Services Directorate at the Glenn Research Center]; Drinking Water Database; Design of an EXB Probe; and Texturing Carbon-carbon Composite Radiator Surfaces Utilizing Atomic Oxygen.

  2. Mineral Commodity Summaries 2011

    Science.gov (United States)

    ,

    2011-01-01

    Each chapter of the 2011 edition of the U.S. Geological Survey (USGS) Mineral Commodity Summaries (MCS) includes information on events, trends, and issues for each mineral commodity as well as discussions and tabular presentations on domestic industry structure, Government programs, tariffs, 5-year salient statistics, and world production and resources. The MCS is the earliest comprehensive source of 2010 mineral production data for the world. More than 90 individual minerals and materials are covered by two-page synopses. For mineral commodities for which there is a Government stockpile, detailed information concerning the stockpile status is included in the two-page synopsis. Mineral Commodity Summaries 2011 contains new chapters on iron oxide pigments, wollastonite, and zeolites. The chapters on mica (natural), scrap and flake and mica (natural), sheet have been combined into a single chapter - mica (natural). Abbreviations and units of measure, and definitions of selected terms used in the report, are in Appendix A and Appendix B, respectively. "Appendix C - Reserves and Resources" has been divided into "Part A - Resource/Reserve Classification for Minerals" and "Part B - Sources of Reserves Data," including some information that was previously in this introduction. A directory of USGS minerals information country specialists and their responsibilities is Appendix D. The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the MCS 2011 are welcomed.

  3. Summary of main points

    International Nuclear Information System (INIS)

    2006-01-01

    In conjunction with its 6. annual meeting, the WPDD in close co-operation with the FSC held a Topical session on 'Stakeholder Involvement in Decommissioning' on November 14, 2005. The session was attended by 36 participants totally representing 14 NEA member countries and 2 international organisations. Two keynote addresses were given at the Topical Session. The first one treated of what is needed for robust decisions and how to bring all stakeholders into the debate. In the second keynote address a summary was made on what have been said on stakeholder involvement in decommissioning during earlier meetings of the WPDD. The main part of the session was then devoted to views from different stakeholders regarding their role and their involvement. This part contained viewpoints from local communities (Kaevlinge in Sweden and Port Hope in Canada), authorities (Scottish Executive and CSNC) and operators (EDF from France and EWN from Germany). Case studies from the decommissioning of Dounrey in the UK and from Trojan and Main Yankee in the USA were presented in the end part of the Topical session followed by a summary and lessons learnt report by the Rapporteur. A detailed programme of the Topical session can be seen in Appendix 1

  4. Testing a Regenerative Carbon Dioxide and Moisture Removal Technology

    Science.gov (United States)

    Barta, Daniel J.; Button, Amy; Sweterlitsch, Jeffrey J.; Curley, Suzanne

    2010-01-01

    The National Aeronautics and Space Administration supported the development of a new vacuum-desorbed regenerative carbon dioxide and humidity control technology for use in short duration human spacecraft. The technology was baselined for use in the Orion Crew Exploration Vehicle s Environmental Control and Life Support System (ECLSS). Termed the Carbon Dioxide And Moisture Removal Amine Swing-bed (CAMRAS), the unit was developed by Hamilton Sundstrand and has undergone extensive testing at Johnson Space Center. The tests were performed to evaluate performance characteristics under range of operating conditions and human loads expected in future spacecraft applications, as part of maturation to increase its readiness for flight. Early tests, conducted at nominal atmospheric pressure, used human metabolic simulators to generate loads, with later tests making us of human test subjects. During these tests many different test cases were performed, involving from 1 to 6 test subjects, with different activity profiles (sleep, nominal and exercise). These tests were conducted within the airlock portion of a human rated test chamber sized to simulate the Orion cabin free air volume. More recently, a test was completed that integrated the CAMRAS with a simulated suit loop using prototype umbilicals and was conducted at reduced atmospheric pressure and elevated oxygen levels. This paper will describe the facilities and procedures used to conduct these and future tests, and provide a summary of findings.

  5. Selective recovery of titanium dioxide from low grade sources

    CSIR Research Space (South Africa)

    Van Vuuren, DS

    2006-09-01

    Full Text Available There are a number of readily available, large reserves of titanium dioxide bearing minerals from which the titanium dioxide cannot currently be economically recovered via current commercial recovery processes due to: The grade of titanium dioxide...

  6. Reactivity of lignin with different composition of aromatic syringyl/guaiacyl structures and erythro/threo side chain structures in β-O-4 type during alkaline delignification: as a basis for the different degradability of hardwood and softwood lignin.

    Science.gov (United States)

    Shimizu, Satoko; Yokoyama, Tomoya; Akiyama, Takuya; Matsumoto, Yuji

    2012-07-04

    The reactivity of lignin during alkaline delignification was quantitatively investigated focusing on the effect of the structural differences between syringyl and guaiacyl aromatic nuclei and between erythro and threo in the side chain of β-O-4 type lignin substructure on the β-O-4 bond cleavage rate. It was known that the ratio of this reaction rate of the erythro to threo isomers of the dimeric β-O-4 type lignin model compound with two guaiacyl aromatic nuclei was ca. 4. However, the presence of a syringyl nucleus strongly influenced the rate, and the ratio of the syringyl type analogue was in the range between 2.7 and 8.0 depending on the reaction temperature. The effect of syringyl nucleus on the enhancement of the reaction rate appeared to be greater when the syringyl nucleus consists of the cleaving ether bond rather than being a member of the carbon framework.

  7. Neutrino physics: Summary talk

    International Nuclear Information System (INIS)

    Marciano, W.J.

    1989-04-01

    This paper is organized as follows: First, I describe the state of neutrino phenomenology. Emphasis is placed on sin 2 θ W , its present status and future prospects. In addition, some signatures of ''new physics'' are described. Then, kaon physics at Fermilab is briefly discussed. I concentrate on the interesting rare decay K L → π 0 e + e - which may be a clean probe direct CP violation. Neutrino mass, mixing, and electromagnetic moments are surveyed. There, I describe the present state and future direction of accelerator based experiments. Finally, I conclude with an outlook on the future. Throughout this summary, I have drawn from and incorporated ideas discussed by other speakers at this workshop. However, I have tried to combine their ideas with my own perspective on neutrino physics and where it is headed. 49 refs., 3 figs., 4 tabs

  8. National COPD conference summary.

    Science.gov (United States)

    Buist, A Sonia; Bailey, William; Hurd, Suzanne S

    2004-01-01

    The first National COPD Conference, sponsored by the US COPD Coalition was held in Arlington, Virginia on November 14-15, 2003. The theme for the conference was developed around the Department of Health and Human Services (DHHS) Healthy People 2010 goals for COPD and included plenary speeches, roundtable discussions, abstracts, and workshops on spirometry, patient/physician education materials, and home monitoring/telemetry. The goal was to bring together a multidisciplinary group to identify important issues relating to COPD in the United States, specifically the barriers to a wider recognition of the disease, and to develop an orchestrated action plan. Over 500 scientists, clinicians, respiratory therapists, nurses, patients, government officials, and representatives from pharmaceutical companies participated. This summary provides the recommendations from the conference that will be used to develop an action plan for the US COPD Coalition. It includes actions proposed by plenary speakers, roundtable faculty and conference participants.

  9. Sulfur Dioxide Analyzer Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Springston, Stephen R. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-05-01

    The Sulfur Dioxide Analyzer measures sulfur dioxide based on absorbance of UV light at one wavelength by SO2 molecules which then decay to a lower energy state by emitting UV light at a longer wavelength. Specifically, SO2 + hυ1 →SO2 *→SO2 + hυ2 The emitted light is proportional to the concentration of SO2 in the optical cell. External communication with the analyzer is available through an Ethernet port configured through the instrument network of the AOS systems. The Model 43i-TLE is part of the i-series of Thermo Scientific instruments. The i-series instruments are designed to interface with external computers through the proprietary Thermo Scientific iPort Software. However, this software is somewhat cumbersome and inflexible. Brookhaven National Laboratory (BNL) has written an interface program in National Instruments LabView that both controls the Model 43i-TLE Analyzer AND queries the unit for all measurement and housekeeping data. The LabView vi (the software program written by BNL) ingests all raw data from the instrument and outputs raw data files in a uniform data format similar to other instruments in the AOS and described more fully in Section 6.0 below.

  10. Sonochemical reduction of carbon dioxide.

    Science.gov (United States)

    Harada, H

    1998-06-01

    Sonolysis of carbon dioxide dissolved in water was performed from a standpoint of reducing this material in atmosphere. During one hour of sonication, the amount of CO2 decreased to about half at 5 degrees C under CO2-Ar atmosphere. The decreasing rate for CO2 followed the order Ar > He > H2 > N2 and it was down with increasing temperature in the range of 5-45 degrees C. The most favorable concentration for reducing CO2 was 0.03 (mole fraction of CO2 in gas phase). This concentration in gas phase means an equal mixture of CO2 and Ar in water, because CO2 is more soluble than Ar. Since carbon dioxide dissolved in water would be partly ionized, the roles of ions on the sonolysis were also examined. Gaseous reaction products were CO, H2 and a small amount of O2. Carbon monoxide and hydrogen might be obtained from CO2 and H2O by sonolysis, respectively. Both gases are fuel and react each other to C1 compounds such as methanol, and so on. Therefore, irradiation of ultrasonic waves should be an important technique for reducing CO2.

  11. Summary: Hadron dynamics sessions

    International Nuclear Information System (INIS)

    Carroll, A.S.; Londergan, J.T.

    1993-01-01

    Four sessions on Hadron Dynamics were organized at this Workshop. The first topic, QCD Exclusive Reactions and Color Transparency, featured talks by Ralston, Heppelman and Strikman; the second, QCD and Inclusive Reactions had talks by Garvey, Speth and Kisslinger. The third dynamics session, Medium Modification of Elementary Interactions had contributions from Kopeliovich, Alves and Gyulassy; the fourth session Pre-QCD Dynamics and Scattering, had talks by Harris, Myhrer and Brown. An additional joint Spectroscopy/Dynamics session featured talks by Zumbro, Johnson and McClelland. These contributions are reviewed briefly in this summary. Two additional joint sessions between Dynamics and η physics are reviewed by the organizers of the Eta sessions. In such a brief review there is no way the authors can adequately summarize the details of the physics presented here. As a result, they concentrate only on brief impressionistic sketches of the physics topics discussed and their interrelations. They include no bibliography in this summary, but simply refer to the talks given in more detail in the Workshop proceedings. They focus on topics which were common to several presentations in these sessions. First, nuclear and particle descriptions of phenomena are now clearly converging, in both a qualitative and quantitative sense; they show several examples of this convergence. Second, an important issue in hadron dynamics is the extent to which elementary interactions are modified in nuclei at high energies and/or densities, and they illustrate some of these medium effects. Finally, they focus on those dynamical issues where hadron facilities can make an important, or even a unique, contribution to the knowledge of particle and nuclear physics

  12. Summary: Hadron dynamics sessions

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, A.S. [Brookhaven National Lab., Upton, NY (United States); Londergan, J.T. [Indiana Univ., Bloomington, IN (United States)

    1993-11-01

    Four sessions on Hadron Dynamics were organized at this Workshop. The first topic, QCD Exclusive Reactions and Color Transparency, featured talks by Ralston, Heppelman and Strikman; the second, QCD and Inclusive Reactions had talks by Garvey, Speth and Kisslinger. The third dynamics session, Medium Modification of Elementary Interactions had contributions from Kopeliovich, Alves and Gyulassy; the fourth session Pre-QCD Dynamics and Scattering, had talks by Harris, Myhrer and Brown. An additional joint Spectroscopy/Dynamics session featured talks by Zumbro, Johnson and McClelland. These contributions are reviewed briefly in this summary. Two additional joint sessions between Dynamics and {eta} physics are reviewed by the organizers of the Eta sessions. In such a brief review there is no way the authors can adequately summarize the details of the physics presented here. As a result, they concentrate only on brief impressionistic sketches of the physics topics discussed and their interrelations. They include no bibliography in this summary, but simply refer to the talks given in more detail in the Workshop proceedings. They focus on topics which were common to several presentations in these sessions. First, nuclear and particle descriptions of phenomena are now clearly converging, in both a qualitative and quantitative sense; they show several examples of this convergence. Second, an important issue in hadron dynamics is the extent to which elementary interactions are modified in nuclei at high energies and/or densities, and they illustrate some of these medium effects. Finally, they focus on those dynamical issues where hadron facilities can make an important, or even a unique, contribution to the knowledge of particle and nuclear physics.

  13. Carbon dioxide sequestration by mineral carbonation

    NARCIS (Netherlands)

    Huijgen, W.J.J.

    2007-01-01

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

  14. Carbon Dioxide for pH Control

    Energy Technology Data Exchange (ETDEWEB)

    Wagonner, R.C.

    2001-08-16

    Cardox, the major supplier of carbon dioxide, has developed a diffuser to introduce carbon dioxide into a water volume as small bubbles to minimize reagent loss to the atmosphere. This unit is integral to several configurations suggested for treatment to control alkalinity in water streams.

  15. Pressure pumping of carbon dioxide from soil

    Science.gov (United States)

    E. S. Takle; J. R. Brandle; R. A. Schmidt; R. Garcia; I. V. Litvina; G. Doyle; X. Zhou; Q. Hou; C. W. Rice; W. J. Massman

    2000-01-01

    Recent interest in atmospheric increases in carbon dioxide have heightened the need for improved accuracy in measurements of fluxes of carbon dioxide from soils. Diffusional movement has long been considered the dominant process by which trace gases move from the subsurface source to the surface, although there has been some indication that atmospheric pressure...

  16. Thermoexpanded graphite modification by titanium dioxide

    International Nuclear Information System (INIS)

    Semko, L.S.; Gorbik, P.P.; Chujko, O.O.; Kruchek, Ya.Yi.; Dzyubenko, L.S.; Orans'ka, O.Yi.

    2006-01-01

    A method of the synthesis of thermoexpanded graphite (TEG) powders coated by titanium dioxide is developed. The conversion of n-buthylorthotitanate into TiO 2 on the TEG surface is investigated. The optimal parameters of the synthesis and the structure of titanium dioxide clusters on the TEG surface are determined

  17. Carbon dioxide disposal in solid form

    Energy Technology Data Exchange (ETDEWEB)

    Lackner, K.S.; Butt, D.P.; Sharp, D.H. [Los Alamos National Lab., NM (United States); Wendt, C.H. [Auxon Corp., (United States)

    1995-12-31

    Coal reserves can provide for the world`s energy needs for centuries. However, coal`s long term use may be severely curtailed if the emission of carbon dioxide into the atmosphere is not eliminated. We present a safe and permanent method of carbon dioxide disposal that is based on combining carbon dioxide chemically with abundant raw materials to form stable carbonate minerals. We discuss the availability of raw materials and potential process designs. We consider our initial rough cost estimate of about 3{cents}/kWh encouraging. The availability of a carbon dioxide fixation technology would serve as insurance in case global warming, or the perception of global warming, causes severe restrictions on carbon dioxide emissions. If the increased energy demand of a growing world population is to be satisfied from coal, the implementation of such a technology would quite likely be unavoidable.

  18. Standards development status. Summary report

    International Nuclear Information System (INIS)

    1981-12-01

    The Standards Development Status Summary Report is designed for scheduling, monitoring, and controlling the process by which Regulatory Standards, Guides, Reports, Petitions, and Environmental Statements are written. It is a summary of the current schedule plans for development of the above products

  19. METHODOLOGICAL ASPECTS OF MOLASSES SAMPLE PREPARATION IN SULFUR DIOXIDE CONTENT DETERMINING

    Directory of Open Access Journals (Sweden)

    M. I. Egorova

    2015-01-01

    Full Text Available Summary. Molasses is characterized as sugar production by-product from primary or secondary sacchariferous raw materials. The features of the appearance, the chemical composition, molasses and exit directions of its use, depending on the type of production, in which it is formed. The value of molasses is demonstrated according to its total composition as well as its use directions. Statistics on beet molasses amounts in Russia is presented. Described consumer market molasses in Russia and abroad with its exports. Shown regulations contain requirements for the quality and safety of molasses, including sulfur dioxide. The data on sulfur allergenic properties are presented. Showing source of the sulfur dioxide in the residual molasses number of processing aids and the impact of its level in the value of raw molasses for use in biotechnological processes and fodder production. The necessity to develop methodology for determining the sulfur dioxide content in the molasses to control its security. The iodometric method, which is used in practice for determination of sulphur dioxide in foods are characterized. Differences molasses and sugar as objects of iodometric determination of sulfur dioxide, which leads to the inability to ascertain the equivalence point. The variants eliminate interfering background of dark-colored foods common in analytical chemistry. Advantages and disadvantages of the background masking and stripping the determination of sulfur dioxide in the darkcolored products. It was characterized by clarifying sugar solutions in optical control methods. The hypothesis about preferability of its use in sample molasses preparation for equivalence point fixation in iodometric titration is suggested. The tasks of experimental research for the development of sample preparation algorithm molasses in determining the content of sulphurous acid.

  20. Master index for the carbon dioxide research state-of-the-art report series

    Energy Technology Data Exchange (ETDEWEB)

    Farrell, M P [ed.

    1987-03-01

    Four State of the Art (SOA) reports, ''Atmospheric Carbon Dioxide and the Global Carbon Cycle,'' ''Direct Effects of Increasing Carbon Dioxide on Vegetation,'' ''Detecting the Climatic Effects of Increasing Carbon Dioxide,'' and ''Projecting the Climatic Effects of Increasing Carbon Dioxide,'' and two companion reports, ''Characterization of Information Requirements for Studies of CO/sub 2/ Effects: Water Resources, Agriculture, Fisheries, Forests and Human Health'' and ''Glaciers, Ice Sheets, and Sea Level: Effect of a CO/sub 2/-Induced Climatic Change,'' were published by the US Department of Energy's Carbon Dioxide Research Division. Considerable information on atmospheric carbon dioxide and its possible effects on world climate is summarized in these six volumes. Each volume has its own index, but to make the information that is distributed throughout the six volumes more accessible and usable, comprehensive citation and subject indexes have been compiled. The subject indexes of the individual volumes have been edited to provide a uniformity from volume to volume and also to draw distinctions not needed in the separate volumes' indexes. Also, the comprehensive subject index has been formatted in a matrix arrangement to graphically show the distribution of subject treatment from volume to volume. Other aids include cross references between the scientific and common names of the animals and plants referred to, a glossary of special terms used, tables of data and conversion factors related to the data, and explanations of the acronyms and initialisms used in the texts of the six volumes. The executive summaries of the six volumes are collected and reproduced to allow the readers interested in the contents of one volume to rapidly gain information on the contents of the other volumes.

  1. Erbium diffusion in titanium dioxide

    Directory of Open Access Journals (Sweden)

    Louise Basse

    2017-04-01

    Full Text Available The diffusivity of erbium in the anatase phase of titanium dioxide (TiO2 has been studied for various temperatures ranging from 800 °C to 1, 000 °C. Samples of TiO2, with a 10 nm thick buried layer containing 0.5 at% erbium, were fabricated by radio-frequency magnetron sputtering and subsequently heat treated. The erbium concentration profiles were measured by secondary ion mass spectrometry, allowing for determination of the temperature-dependent diffusion coefficients. These were found to follow an Arrhenius law with an activation energy of ( 2.1 ± 0.2 eV. X-ray diffraction revealed that the TiO2 films consisted of polycrystalline grains of size ≈ 100 nm.

  2. Nanoparticulate cerium dioxide and cerium dioxide-titanium dioxide composite thin films on glass by aerosol assisted chemical vapour deposition

    International Nuclear Information System (INIS)

    Qureshi, Uzma; Dunnill, Charles W.; Parkin, Ivan P.

    2009-01-01

    Two series of composite thin films were deposited on glass by aerosol assisted chemical vapour deposition (AACVD)-nanoparticulate cerium dioxide and nanoparticulate cerium dioxide embedded in a titanium dioxide matrix. The films were analysed by a range of techniques including UV-visible absorption spectroscopy, X-ray diffraction, scanning electron microscopy and energy dispersive analysis by X-rays. The AACVD prepared films showed the functional properties of photocatalysis and super-hydrophilicity. The CeO 2 nanoparticle thin films displaying photocatalysis and photo-induced hydrophilicity almost comparable to that of anatase titania.

  3. Summary of the Workshop

    International Nuclear Information System (INIS)

    Myers, S; Zimmermann, F

    2012-01-01

    The summary session of the LHC Performance Workshop in Chamonix, 6-10 February 2012, synthesized one week of presentations and intense discussions on the near-, medium- and long-term strategy for the LHC and LHC upgrades. In particular, Chamonix’12 discussed the lessons from 2011, the strategy, beam energy and beam parameters for 2012, the planning for the Long Shutdown no. 1 (LS1), the measures and schemes for improving or maintaining the machine availability at higher beam energy, the injector performance and injector upgrade schedule, the HL-LHC project as well as possible additional or future LHC upgrades like LHeC and HELHC. Key workshop themes included the risk associated with 4 TeV beam energy in 2012, the beam energy after LS1, the turnaround time, the physics goal and optimized running schedule for 2012, the achievements and plans for Pb-Pb and p-Pb collisions, beam-beam effects, electron-cloud phenomena and UFOs. We report the proposals for decisions which have emerged at the Chamonix’12 workshop. (author)

  4. Mineral commodity summaries 2014

    Science.gov (United States)

    ,

    2014-01-01

    Each chapter of the 2014 edition of the U.S. Geological Survey (USGS) Mineral Commodity Summaries (MCS) includes information on events, trends, and issues for each mineral commodity as well as discussions and tabular presentations on domestic industry structure, Government programs, tariffs, 5-year salient statistics, and world production and resources. The MCS is the earliest comprehensive source of 2013 mineral production data for the world. More than 90 individual minerals and materials are covered by two-page synopses. For mineral commodities for which there is a Government stockpile, detailed information concerning the stockpile status is included in the two-page synopsis. Abbreviations and units of measure, and definitions of selected terms used in the report, are in Appendix A and Appendix B, respectively. “Appendix C—Reserves and Resources” includes “Part A—Resource/Reserve Classification for Minerals” and “Part B—Sources of Reserves Data.” A directory of USGS minerals information country specialists and their responsibilities is Appendix D. The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the MCS 2014 are welcomed.

  5. Mineral commodity summaries 2013

    Science.gov (United States)

    ,

    2013-01-01

    Each chapter of the 2013 edition of the U.S. Geological Survey (USGS) Mineral Commodity Summaries (MCS) includes information on events, trends, and issues for each mineral commodity as well as discussions and tabular presentations on domestic industry structure, Government programs, tariffs, 5-year salient statistics, and world production and resources. The MCS is the earliest comprehensive source of 2012 mineral production data for the world. More than 90 individual minerals and materials are covered by two-page synopses. For mineral commodities for which there is a Government stockpile, detailed information concerning the stockpile status is included in the two-page synopsis. Abbreviations and units of measure, and definitions of selected terms used in the report, are in Appendix A and Appendix B, respectively. “Appendix C—Reserves and Resources” includes “Part A—Resource/Reserve Classification for Minerals” and “Part B—Sources of Reserves Data.” A directory of USGS minerals information country specialists and their responsibilities is Appendix D. The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the MCS 2013 are welcomed.

  6. Astronautics summary and prospects

    CERN Document Server

    Kiselev, Anatoly Ivanovich; Menshikov, Valery Alexandrovich

    2003-01-01

    The monograph by A.I.Kiselev, A.A. Medvedev and Y.A.Menshikov, Astronautics: Summary and Prospects, aroused enthusiasm both among experts and the public at large. This is due to the felicitous choice of presentation that combines a simple description of complex space matters with scientificsubstantiation of the sub­ jectmatter described. The wealth of color photos makes the book still more attractive, and it was nominated for an award at the 14th International Moscow Book Fair, being singled out as the "best publication of the book fair". The book's popularity led to a second edition, substantially revised and enlarged. Since the first edition did not sufficiently cover the issues of space impact on ecology and the prospective development of space systems, the authors revised the entire volume, including in it the chapter "Space activity and ecology" and the section "Multi-function space systems". Using the federal monitoring system, now in the phase of system engi­ neering, as an example, the authors consi...

  7. Carbon dioxide for the recovery of crude oil: a literature search to June 30, 1979. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Doscher, T.

    1980-05-01

    Individual summaries and pertinent commentaries on each of the groups of references into which the literature on carbon dioxide for the recovery of crude oil has been classified are presented in this report. The major classifications are: physical models, laboratory studies, field tests, modelling, patents, and miscellaneous. A special summary that reviews and comments on field operations, fluid handling, and corrosion problems is also included. User's guide and subject categories for the CO/sub 2/ literature survey are given, followed by abstracts of the citations. It is concluded from this survey that the most significant deficiency in research on carbon dioxide flooding for the recovery of crude oil is the paucity of well controlled and interpreted field tests.

  8. A Summary of Aluminum Combustion

    National Research Council Canada - National Science Library

    Beckstead, M

    2004-01-01

    .... The exponent is shown to be less than two, with nominal values of 1.5 to 1.8 being typical. The effect of oxidizer is pronounced with oxygen being twice as effective as water and about five times more effective than carbon dioxide...

  9. 49 CFR 173.217 - Carbon dioxide, solid (dry ice).

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Carbon dioxide, solid (dry ice). 173.217 Section... Class 7 § 173.217 Carbon dioxide, solid (dry ice). (a) Carbon dioxide, solid (dry ice), when offered for... marked on two sides “WARNING CO2 SOLID (DRY ICE).” (2) Other packagings containing solid carbon dioxide...

  10. Summary 2010 Greenhouse Gas Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — This file contains a summary of the publicly available data from the GHG Reporting Program for 2010. This data includes non-confidential data reported by facilities...

  11. Summary of the Day (CDMP)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This Summary of the Day data file contains daily selected elements of observations recorded by certified observers. The stations were located in the U.S. and were...

  12. Lunar Core Drive Tubes Summary

    Data.gov (United States)

    National Aeronautics and Space Administration — Contains a brief summary and high resolution imagery from various lunar rock and core drive tubes collected from the Apollo and Luna missions to the moon.

  13. School Construction Summary, Fiscal 1967.

    Science.gov (United States)

    Michigan State Dept. of Education, Lansing.

    A tabular summary of school construction--public and non public--in Michigan for fiscal year 1967 is presented. Discussions of small projects approvals, transportable buildings, future construction, and special facilities are included. (FPO)

  14. Reactive Capture of Carbon Dioxide Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Phase I SBIR, Reactive Innovations, LLC (RIL) proposes to develop a compact and lightweight electrochemical to capture carbon dioxide in the martian...

  15. Encapsulated liquid sorbents for carbon dioxide capture.

    Science.gov (United States)

    Vericella, John J; Baker, Sarah E; Stolaroff, Joshuah K; Duoss, Eric B; Hardin, James O; Lewicki, James; Glogowski, Elizabeth; Floyd, William C; Valdez, Carlos A; Smith, William L; Satcher, Joe H; Bourcier, William L; Spadaccini, Christopher M; Lewis, Jennifer A; Aines, Roger D

    2015-02-05

    Drawbacks of current carbon dioxide capture methods include corrosivity, evaporative losses and fouling. Separating the capture solvent from infrastructure and effluent gases via microencapsulation provides possible solutions to these issues. Here we report carbon capture materials that may enable low-cost and energy-efficient capture of carbon dioxide from flue gas. Polymer microcapsules composed of liquid carbonate cores and highly permeable silicone shells are produced by microfluidic assembly. This motif couples the capacity and selectivity of liquid sorbents with high surface area to facilitate rapid and controlled carbon dioxide uptake and release over repeated cycles. While mass transport across the capsule shell is slightly lower relative to neat liquid sorbents, the surface area enhancement gained via encapsulation provides an order-of-magnitude increase in carbon dioxide absorption rates for a given sorbent mass. The microcapsules are stable under typical industrial operating conditions and may be used in supported packing and fluidized beds for large-scale carbon capture.

  16. Carbon Dioxide Collection and Pressurization Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Reactive Innovations, LLC, proposes a Phase I SBIR program to develop a compact and lightweight electrochemical reactor to separate and pressurize carbon dioxide...

  17. Life Support Systems: Carbon Dioxide Removal

    Data.gov (United States)

    National Aeronautics and Space Administration — The Advanced Exploration Systems (AES) Life Support Systems project Carbon Dioxide Removal and Management task includes development of systems that remove CO2 from a...

  18. High performance hydrophobic solvent, carbon dioxide capture

    Science.gov (United States)

    Nulwala, Hunaid; Luebke, David

    2017-05-09

    Methods and compositions useful, for example, for physical solvent carbon capture. A method comprising: contacting at least one first composition comprising carbon dioxide with at least one second composition to at least partially dissolve the carbon dioxide of the first composition in the second composition, wherein the second composition comprises at least one siloxane compound which is covalently modified with at least one non-siloxane group comprising at least one heteroatom. Polydimethylsiloxane (PDMS) materials and ethylene-glycol based materials have high carbon dioxide solubility but suffer from various problems. PDMS is hydrophobic but suffers from low selectivity. Ethylene-glycol based systems have good solubility and selectivity, but suffer from high affinity to water. Solvents were developed which keep the desired combinations of properties, and result in a simplified, overall process for carbon dioxide removal from a mixed gas stream.

  19. Overview and summary

    International Nuclear Information System (INIS)

    1999-01-01

    The ITER Physics Basis presents and evaluates the physics rules and methodologies for plasma performance projections, which provide the basis for the design of a tokamak burning plasma device whose goal is to demonstrate the scientific and technological feasibility of fusion energy for peaceful purposes. This Chapter summarizes the physics basis for burning plasma projections, which is developed in detail by the ITER Physics Expert Groups in subsequent chapters. To set context, the design guidelines and requirements established in the report of ITER Special Working Group 1 are presented, as are the specifics of the tokamak design developed in the Final Design Report of the ITER Engineering Design Activities, which exemplifies burning tokamak plasma experiments. The behaviour of a tokamak plasma is determined by the interaction of many diverse physics processes, all of which bear on projections for both a burning plasma experiment and an eventual tokamak reactor. Key processes summarized here are energy and particle confinement and the H-mode power threshold; MHD stability, including pressure and density limits, neoclassical islands, error fields, disruptions, sawteeth, and ELMs; power and particle exhaust, involving divertor power dispersal, helium exhaust, fuelling and density control, H-mode edge transition region, erosion of plasma facing components, tritium retention; energetic particle physics; auxiliary power physics; and the physics of plasma diagnostics. Summaries of projection methodologies, together with estimates of their attendant uncertainties, are presented in each of these areas. Since each physics element has its own scaling properties, an integrated experimental demonstration of the balance between the combined processes which obtains in a reactor plasma is inaccessible to contemporary experimental facilities: it requires a reactor scale device. It is argued, moreover, that a burning plasma experiment can be sufficiently flexible to permit

  20. Safeguards Summary Event List (SSEL)

    International Nuclear Information System (INIS)

    1982-07-01

    The Safeguards Summary Event List (SSEL) provides brief summaries of several hundred safeguards-related events involving nuclear material or facilities regulated by the US Nuclear Regulatory Commission (NRC). Events are described under the categories of bomb-related, intrusion, missing and/or allegedly stolen, transportation, vandalism, arson, firearms, sabotage and miscellaneous. The information contained in the event descriptions is derived primarily from official NRC reporting channels

  1. Safeguards Summary Event List (SSEL)

    International Nuclear Information System (INIS)

    1983-02-01

    The Safeguards Summary Event List (SSEL) provides brief summaries of several hundred safeguards-related events involving nuclear material or facilities regulated by the US Nuclear Regulatory Commission (NRC). Events are described under the categories of bomb-related, intrusion, missing and/or allegedly stolen, transportation, vandalism, arson, firearms, radiological sabotage and miscellaneous. The information contained in the event descriptions is derived primarily from official NRC reporting channels

  2. Safeguards Summary Event List (SSEL)

    International Nuclear Information System (INIS)

    1984-03-01

    The Safeguards Summary Event List (SSEL) provides brief summaries of several hundred safeguards-related events involving nuclear material or facilities regulated by the U.S. Nuclear Regulatory Commission (NRC). Events are described under the categories of bomb-related, intrusion, missing and/or allegedly stolen, transportation, tampering/vandalism, arson, firearms, radiological sabotage and miscellaneous. The information contained in the event descriptions is derived primarily from official NRC reporting channels

  3. Renal artery intervention utilizing carbon dioxide angiography.

    Science.gov (United States)

    Sag, Alan A; Afsar, Baris; Kanbay, Mehmet

    2017-12-01

    Carbon dioxide angiography is an established non-nephrotoxic option for imaging of the infradiaphragmatic arteries and veins. Safe performance of the technique once required a somewhat cumbersome system, however, recent innovations have simplified implementation and expanded the user base for this technique. As such, patient access has also increased. In this issue, Hameed et al. provide initial feasibility data regarding carbon dioxide angiography and renal denervation therapy. This experience may be translated into future renovascular interventions in patients with limited renal reserve.

  4. Thorium dioxide: properties and nuclear applications

    International Nuclear Information System (INIS)

    Belle, J.; Berman, R.M.

    1984-01-01

    This is the sixth book on reactor materials published under sponsorship of the Naval Reactors Office of the United States Department of Energy, formerly the United States Atomic Energy Commission. This book presents a comprehensive compilation of the most significant properties of thorium dioxide, much like the book Uranium Dioxide: Properties and Nuclear Applications presented information on the fuel material used in the Shippingport Pressurized Water Reactor core

  5. Surface and bulk conductivity of vanadium dioxide

    Science.gov (United States)

    Tutov, E. A.; Manannikov, A. V.; Al-Khafaji, H. I.; Zlomanov, V. P.

    2017-03-01

    The dc and ac resistances of a TR-68 thermistor based on the vanadium dioxide film have been measured and the temperature dependence of the resistance in the semiconductor-metal transition region under adsorption has been studied. The energy band model has been proposed, which explains the anomalous response to adsorption of donor gases by the inversion of the conductivity type of vanadium dioxide surface layers.

  6. Thorium dioxide: properties and nuclear applications

    Energy Technology Data Exchange (ETDEWEB)

    Belle, J.; Berman, R.M. (eds.)

    1984-01-01

    This is the sixth book on reactor materials published under sponsorship of the Naval Reactors Office of the United States Department of Energy, formerly the United States Atomic Energy Commission. This book presents a comprehensive compilation of the most significant properties of thorium dioxide, much like the book Uranium Dioxide: Properties and Nuclear Applications presented information on the fuel material used in the Shippingport Pressurized Water Reactor core.

  7. SEQUESTERING CARBON DIOXIDE IN COALBEDS

    Energy Technology Data Exchange (ETDEWEB)

    K.A.M. Gasem; R.L. Robinson, Jr.; L.R. Radovic

    2001-06-15

    During the present reporting period, six complementary tasks involving experimentation, model development, and coal characterization were undertaken to meet our project objectives: (1) A second adsorption apparatus, utilizing equipment donated by BP Amoco, was assembled. Having confirmed the reliability of this additional experimental apparatus and procedures, adsorption isotherms for CO{sub 2}, methane, ethane, and nitrogen on wet Fruitland coal and on activated carbon were measured at 319.3 K (115 F) and pressures to 12.4 MPa (1800 psia). These measurements showed good agreement with our previous data and yielded an expected uncertainty of about 3%. The addition of this new facility has allowed us to essentially double our rate of data production. (2) Adsorption isotherms for pure CO{sub 2}, methane, and nitrogen on wet Illinois-6 coal and on activated carbon were measured at 319.3 K (115 F) and pressures to 12.4 MPa (1800 psia) on our first apparatus. The activated carbon measurements showed good agreement with literature data and with measurements obtained on our second apparatus. The expected uncertainty of the data is about 3%. The Illinois-6 adsorption measurements are a new addition to the existing database. Preparations are underway to measure adsorption isotherms for pure methane, carbon dioxide and nitrogen on DESC-8 coal. (3) Adsorption from binary mixtures of methane, nitrogen and CO{sub 2} at a series of compositions was also measured on the wet Fruitland coal at 319.3 K (115 F), using our first apparatus. The nominal compositions of these mixtures are 20%/80%, 40%/60%, 60%/40%, and 80%/20%. The experiments were conducted at pressures from 100 psia to 1800 psia. The expected uncertainty for these binary mixture data varies from 2 to 9%. (4) A study was completed to address the previously-reported rise in the CO{sub 2} absolute adsorption on wet Fruitland coal at 115 F and pressures exceeding 1200 psia. Our additional adsorption measurements on

  8. Report of the Carbon Dioxide Committee II

    International Nuclear Information System (INIS)

    1994-01-01

    The Carbon Dioxide Committee was given the task of preparing a suggestion of the acts aimed at reducing the greenhouse gas emissions and increasing the sinks of carbon in Finland. Emissions of all greenhouse gases were in 1990 80 million tons. calculated as carbon dioxide. The carbon dioxide emissions were about 58 million tons of the total. The increase of forest resources binds carbon from the atmosphere and reduces thereby net emissions of Finland at present by nearly 30 million tons of carbon dioxide. Carbon dioxide emissions will grow during the next decades, unless strong measures to control them will not be taken. As a result of the Commissions examination, acts will be needed both in the production of energy and in its consumption. Emissions can be reduced by replacing fossil fuels with nuclear energy, bioenergy and other renewable energy sources. Saving of energy and improvement of energy efficiency will limit carbon dioxide emissions. The Commission has made suggestions both to change the structure of energy production and to control the consumption of energy. (orig.)

  9. Low Energy, Low Emissions: Sulfur Dioxide; Nitrogen Oxides, and Carbon Dioxide in Western Europe.

    Science.gov (United States)

    Alcamo, Joseph; De Vries, Bert

    1992-01-01

    Links proposed low-energy scenarios for different Western European countries with the amount of pollutants that may result from these scenarios. Sulfur dioxide, nitrogen oxide, and carbon dioxide emissions are calculated for the 10 countries for which low-energy scenarios are available, resulting in reductions of 54%, 37%, and 40%, respectively.…

  10. Does Writing Summaries Improve Memory for Text?

    Science.gov (United States)

    Spirgel, Arie S.; Delaney, Peter F.

    2016-01-01

    In five experiments, we consistently found that items included in summaries were better remembered than items omitted from summaries. We did not, however, find evidence that summary writing was better than merely restudying the text. These patterns held with shorter and longer texts, when the text was present or absent during the summary writing,…

  11. Executive Summary - Overview

    International Nuclear Information System (INIS)

    2005-01-01

    Professor Andrzej Budzanowski was Director of IFJ in the years 1990-2004. On September 1st 2004, on IFJ joining the Polish Academy of Sciences, Professor Marek Jezabek has been nominated by the President of PAN as the Director of IFJ, for a 4-year term. Our Institute, with a personnel of 450 (182 research staff) and over 50 Ph.D. students, is presently one of the largest institutes of the Polish Academy of Sciences and one of the largest research institutes in Poland. The scientific staff consists on 120 post-doctoral researchers, 26 Associated Professors and 36 State-Nominated Professors. The total budget of the Institute for the year 2004 was about 56 million Euro. The IFJ is financed mainly from the state budget of the Ministry of Scientific Research and Information Technology. In 2004 this financing was about 4 million Euro, constituting 72% of the Institute's total budget. The remaining part of our 2004 budget came from individual research projects, also sponsored by the Ministry of Scientific Research (688 kEuro), from international projects (368 kEuro) and from the Institute's entrepreneurship activities (498 kEuro). Between 2003 and 2004 we doubled our income from international projects. For further budget information. The Scientific Council of the Institute, which consists of 40 elected members of the Institute's staff and 4 external members (elected representatives from other Polish institutes and universities), is authorized to confer Ph.D. degrees in Physics and related disciplines, and to initiate and conduct habilitation and professorship procedures. In 2003-2004 17 Ph.D. theses and 11 habilitations have been completed. Following their review procedures, 3 Associate Professors at the IFJ became state-nominated Professors, receiving their nominations from Poland's President, Mr. A. Kwasniewski. The Institute is structured into 17 scientific departments which cover the range of our scientific interests. A summary of our main scientific achievements in

  12. Carbon dioxide capture process with regenerable sorbents

    Science.gov (United States)

    Pennline, Henry W.; Hoffman, James S.

    2002-05-14

    A process to remove carbon dioxide from a gas stream using a cross-flow, or a moving-bed reactor. In the reactor the gas contacts an active material that is an alkali-metal compound, such as an alkali-metal carbonate, alkali-metal oxide, or alkali-metal hydroxide; or in the alternative, an alkaline-earth metal compound, such as an alkaline-earth metal carbonate, alkaline-earth metal oxide, or alkaline-earth metal hydroxide. The active material can be used by itself or supported on a substrate of carbon, alumina, silica, titania or aluminosilicate. When the active material is an alkali-metal compound, the carbon-dioxide reacts with the metal compound to generate bicarbonate. When the active material is an alkaline-earth metal, the carbon dioxide reacts with the metal compound to generate carbonate. Spent sorbent containing the bicarbonate or carbonate is moved to a second reactor where it is heated or treated with a reducing agent such as, natural gas, methane, carbon monoxide hydrogen, or a synthesis gas comprising of a combination of carbon monoxide and hydrogen. The heat or reducing agent releases carbon dioxide gas and regenerates the active material for use as the sorbent material in the first reactor. New sorbent may be added to the regenerated sorbent prior to subsequent passes in the carbon dioxide removal reactor.

  13. Designed amyloid fibers as materials for selective carbon dioxide capture.

    Science.gov (United States)

    Li, Dan; Furukawa, Hiroyasu; Deng, Hexiang; Liu, Cong; Yaghi, Omar M; Eisenberg, David S

    2014-01-07

    New materials capable of binding carbon dioxide are essential for addressing climate change. Here, we demonstrate that amyloids, self-assembling protein fibers, are effective for selective carbon dioxide capture. Solid-state NMR proves that amyloid fibers containing alkylamine groups reversibly bind carbon dioxide via carbamate formation. Thermodynamic and kinetic capture-and-release tests show the carbamate formation rate is fast enough to capture carbon dioxide by dynamic separation, undiminished by the presence of water, in both a natural amyloid and designed amyloids having increased carbon dioxide capacity. Heating to 100 °C regenerates the material. These results demonstrate the potential of amyloid fibers for environmental carbon dioxide capture.

  14. The surface science of titanium dioxide

    Science.gov (United States)

    Diebold, Ulrike

    2003-01-01

    Titanium dioxide is the most investigated single-crystalline system in the surface science of metal oxides, and the literature on rutile (1 1 0), (1 0 0), (0 0 1), and anatase surfaces is reviewed. This paper starts with a summary of the wide variety of technical fields where TiO 2 is of importance. The bulk structure and bulk defects (as far as relevant to the surface properties) are briefly reviewed. Rules to predict stable oxide surfaces are exemplified on rutile (1 1 0). The surface structure of rutile (1 1 0) is discussed in some detail. Theoretically predicted and experimentally determined relaxations of surface geometries are compared, and defects (step edge orientations, point and line defects, impurities, surface manifestations of crystallographic shear planes—CSPs) are discussed, as well as the image contrast in scanning tunneling microscopy (STM). The controversy about the correct model for the (1×2) reconstruction appears to be settled. Different surface preparation methods, such as reoxidation of reduced crystals, can cause a drastic effect on surface geometries and morphology, and recommendations for preparing different TiO 2(1 1 0) surfaces are given. The structure of the TiO 2(1 0 0)-(1×1) surface is discussed and the proposed models for the (1×3) reconstruction are critically reviewed. Very recent results on anatase (1 0 0) and (1 0 1) surfaces are included. The electronic structure of stoichiometric TiO 2 surfaces is now well understood. Surface defects can be detected with a variety of surface spectroscopies. The vibrational structure is dominated by strong Fuchs-Kliewer phonons, and high-resolution electron energy loss spectra often need to be deconvoluted in order to render useful information about adsorbed molecules. The growth of metals (Li, Na, K, Cs, Ca, Al, Ti, V, Nb, Cr, Mo, Mn, Fe, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au) as well as some metal oxides on TiO 2 is reviewed. The tendency to 'wet' the overlayer, the growth morphology, the

  15. Operating reactors licensing actions summary

    International Nuclear Information System (INIS)

    1983-01-01

    The operating reactors licensing actions summary is designed to provide the management of the Nuclear Regulatory Commission (NRC) with an overview of licensing actions dealing with operating power and nonpower reactors. These reports utilize data collected from the Division of Licensing in the Office of Nuclear Reactor Regulation and are prepared by the Office of Management and Program Analysis. This summary report is published primarily for internal NRC use in managing the operating reactors licensing actions program. Its content will change based on NRC management informational requirements

  16. Safeguards Summary Event List (SSEL)

    International Nuclear Information System (INIS)

    Fadden, M.; Yardumian, J.

    1993-07-01

    The Safeguards Summary Event List provides brief summaries of hundreds of safeguards-related events involving nuclear material or facilities regulated by the US Nuclear Regulatory Commission. Events are described under the categories: Bomb-related, Intrusion, Missing/Allegedly Stolen, Transportation-related, Tampering/Vandalism, Arson, Firearms-related, Radiological Sabotage, Non-radiological Sabotage, and Miscellaneous. Because of the public interest, the Miscellaneous category also includes events reported involving source material, byproduct material, and natural uranium, which are exempt from safeguards requirements. Information in the event descriptions was obtained from official NRC sources

  17. Safeguards summary event list (SSEL)

    International Nuclear Information System (INIS)

    1989-07-01

    The Safeguards Summary Event List (SSEL) provides brief summaries of several hundred safeguards-related events involving nuclear material or facilities regulated by the US Nuclear Regulatory Commission (NRC). Because of public interest, also included are events reported involving byproduct material which is exempt from safeguards requirements. Events are described under the categories of bomb-related, intrusion, missing and/or allegedly stolen, transportation, tampering/vandalism, arson, firearms, radiological sabotage, nonradiological sabotage, alcohol and drugs, and miscellaneous. The information contained in the event descriptions is derived primarily from official NRC reporting channels

  18. Experimental Plasma Research project summaries

    International Nuclear Information System (INIS)

    1980-09-01

    This report contains descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Diagnostics; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report

  19. Experimental plasma research project summaries

    International Nuclear Information System (INIS)

    1978-08-01

    This report contans descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Measurements and Instrumentation; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report

  20. Operating reactors licensing actions summary

    International Nuclear Information System (INIS)

    1982-05-01

    The operating reactors licensing actions summary is designed to provide the management of the Nuclear Regulatory Commission (NRC) with an overview of licensing actions dealing with operating power and nonpower reactors. These reports utilize data collected from the Division of Licensing in the Office of Nuclear Reactor Regulation and are prepared by the Office of Management and Program Analysis. This summary report is published primarily for internal NRC use in managing the operating reactors licensing actions program. Its content will change based on NRC management informational requirements

  1. Operating reactors licensing actions summary

    International Nuclear Information System (INIS)

    1982-08-01

    The operating reactors licensing actions summary is designed to provide the management of the Nuclear Regulatory Commission (NRC) with an overview of licensing actions dealing with operating power and nonpower reactors. These reports utilize data collected from the Division of Licensing in the Office of Nuclear Reactor Regulation and are prepared by the Office of Management and Program Analysis. This summary report is published primarily for internal NRC use in managing the operating reactors licensing actions program. Its content will change based on NRC management informational requirements

  2. Operating reactors licensing actions summary

    International Nuclear Information System (INIS)

    1983-03-01

    The operating reactors licensing actions summary is designed to provide the management of the Nuclear Regulatory Commission (NRC) with an overview of licensing actions dealing with operating power and nonpower reactors. These reports utilize data collected from the Division of Licensing in the Office of Nuclear Reactor Regulation and are prepared by the Office of Management and Program Analysis. This summary report is published primarily for internal NRC use in managing the operating reactors licensing actions program. Its content will change based on NRC management informational requirements

  3. Operating reactors licensing actions summary

    International Nuclear Information System (INIS)

    1982-11-01

    The operating reactors licensing actions summary is designed to provide the management of the Nuclear Regulatory Commission (NRC) with an overview of licensing actions dealing with operating power and nonpower reactors. These reports utilize data collected from the Division of Licensing in the Office of Nuclear Reactor Regulation and are prepared by the Office of Management and Program Analysis. This summary report is published primarily for internal NRC use in managing the operating reactors licensing actions program. Its content will change based on NRC management informational requirements

  4. Operating reactors licensing actions summary

    International Nuclear Information System (INIS)

    1982-07-01

    The operating reactors licensing actions summary is designed to provide the management of the Nuclear Regulatory Commission (NRC) with an overview of licensing actions dealing with operating power and nonpower reactors. These reports utilize data collected from the Division of Licensing in the Office of Nuclear Reactor Regulation and are prepared by the Office of Management and Program Analysis. This summary report is published primarily for internal NRC use in managing the operating reactors licensing actions program. Its content will change based on NRC management informational requirements

  5. Turning carbon dioxide into fuel.

    Science.gov (United States)

    Jiang, Z; Xiao, T; Kuznetsov, V L; Edwards, P P

    2010-07-28

    Our present dependence on fossil fuels means that, as our demand for energy inevitably increases, so do emissions of greenhouse gases, most notably carbon dioxide (CO2). To avoid the obvious consequences on climate change, the concentration of such greenhouse gases in the atmosphere must be stabilized. But, as populations grow and economies develop, future demands now ensure that energy will be one of the defining issues of this century. This unique set of (coupled) challenges also means that science and engineering have a unique opportunity-and a burgeoning challenge-to apply their understanding to provide sustainable energy solutions. Integrated carbon capture and subsequent sequestration is generally advanced as the most promising option to tackle greenhouse gases in the short to medium term. Here, we provide a brief overview of an alternative mid- to long-term option, namely, the capture and conversion of CO2, to produce sustainable, synthetic hydrocarbon or carbonaceous fuels, most notably for transportation purposes. Basically, the approach centres on the concept of the large-scale re-use of CO2 released by human activity to produce synthetic fuels, and how this challenging approach could assume an important role in tackling the issue of global CO2 emissions. We highlight three possible strategies involving CO2 conversion by physico-chemical approaches: sustainable (or renewable) synthetic methanol, syngas production derived from flue gases from coal-, gas- or oil-fired electric power stations, and photochemical production of synthetic fuels. The use of CO2 to synthesize commodity chemicals is covered elsewhere (Arakawa et al. 2001 Chem. Rev. 101, 953-996); this review is focused on the possibilities for the conversion of CO2 to fuels. Although these three prototypical areas differ in their ultimate applications, the underpinning thermodynamic considerations centre on the conversion-and hence the utilization-of CO2. Here, we hope to illustrate that advances

  6. SEQUESTERING CARBON DIOXIDE IN COALBEDS

    Energy Technology Data Exchange (ETDEWEB)

    K.A.M. Gasem; R.L. Robinson, Jr.; J.E. Fitzgerald; Z. Pan; M. Sudibandriyo

    2003-04-30

    The authors' long-term goal is to develop accurate prediction methods for describing the adsorption behavior of gas mixtures on solid adsorbents over complete ranges of temperature, pressure, and adsorbent types. The originally-stated, major objectives of the current project are to: (1) measure the adsorption behavior of pure CO{sub 2}, methane, nitrogen, and their binary and ternary mixtures on several selected coals having different properties at temperatures and pressures applicable to the particular coals being studied, (2) generalize the adsorption results in terms of appropriate properties of the coals to facilitate estimation of adsorption behavior for coals other than those studied experimentally, (3) delineate the sensitivity of the competitive adsorption of CO{sub 2}, methane, and nitrogen to the specific characteristics of the coal on which they are adsorbed; establish the major differences (if any) in the nature of this competitive adsorption on different coals, and (4) test and/or develop theoretically-based mathematical models to represent accurately the adsorption behavior of mixtures of the type for which measurements are made. As this project developed, an important additional objective was added to the above original list. Namely, we were encouraged to interact with industry and/or governmental agencies to utilize our expertise to advance the state of the art in coalbed adsorption science and technology. As a result of this additional objective, we participated with the Department of Energy and industry in the measurement and analysis of adsorption behavior as part of two distinct investigations. These include (a) Advanced Resources International (ARI) DOE Project DE-FC26-00NT40924, ''Adsorption of Pure Methane, Nitrogen, and Carbon Dioxide and Their Mixtures on Wet Tiffany Coal'', and (b) the DOE-NETL Project, ''Round Robin: CO{sub 2} Adsorption on Selected Coals''. These activities, contributing

  7. Unravelling the capability of Pyrenophora phaeocomes S-1 for the production of ligno-hemicellulolytic enzyme cocktail and simultaneous bio-delignification of rice straw for enhanced enzymatic saccharification.

    Science.gov (United States)

    Rastogi, Shubhangi; Soni, Raman; Kaur, Jaspreet; Soni, Sanjeev Kumar

    2016-12-01

    A natural variant of Pyrenophora phaeocomes isolated from natural biodiversity was able to grow on various agricultural residues by co-producing laccase, xylanase and mannanase. Solid state fermentation of rice straw induced the highest productivities corresponding to 10,859.51±46.74, 22.01±1.00 and 10.45±0.128IUgds -1 for laccase, xylanase and mannanase respectively after 4days. Besides producing the ligno-hemicellulolytic enzyme cocktail, 40days cultivation of P. phaeocomes S-1 on rice straw brought about the 63 and 51% degradation of lignin and hemicellulose. These components were further removed with mild alkali extraction revealing the overall losses amounting to 78 and 60% respectively for lignin, and hemicellulose. The biologically pretreated straw upon enzymatic hydrolysis revealed 50% saccharification efficiency releasing 470mgg -1 sugars. Application of this knowledge will lead to efficient management of waste rice straw with low cost production of industrially important enzymes cocktail and its biological delignification for effective enzymatic hydrolysis to free sugars. Copyright © 2016. Published by Elsevier Ltd.

  8. Reaction of titanium polonides with carbon dioxide

    International Nuclear Information System (INIS)

    Abakumov, A.S.; Malyshev, M.L.; Reznikova, N.F.

    1987-01-01

    It has been ascertained that heating titanium and tantalum in carbon dioxide to temperatures of 500 or 800 0 C alters the composition of the gas phase, causing the advent of carbon monoxide and lowering the oxygen content. Investigation of the thermal stability of titanium polonides in a carbon dioxide medium has shown that titanium mono- and hemipolonides are decomposed at temperatures below 350 0 C. The temperature dependence of the vapor pressure of polonium produced in the decomposition of these polonides in a carbon dioxide medium have been determined by a radiotensimetric method. The enthalpy of the process, calculated from this relationship, is close to the enthalpy of vaporization of elementary polonium in vacuo

  9. IMPEDANCE SPECTROSCOPY OF POLYCRYSTALLINE TIN DIOXIDE FILMS

    Directory of Open Access Journals (Sweden)

    D. V. Adamchuck

    2016-01-01

    Full Text Available The aim of this work is the analysis of the influence of annealing in an inert atmosphere on the electrical properties and structure of non-stoichiometric tin dioxide films by means of impedance spectroscopy method. Non-stoichiometric tin dioxide films were fabricated by two-step oxidation of metallic tin deposited on the polycrystalline Al2O3 substrates by DC magnetron sputtering. In order to modify the structure and stoichiometric composition, the films were subjected to the high temperature annealing in argon atmosphere in temperature range 300–800 °С. AC-conductivity measurements of the films in the frequency range 20 Hz – 2 MHz were carried out. Variation in the frequency dependencies of the real and imaginary parts of the impedance of tin dioxide films was found to occur as a result of high-temperature annealing. Equivalent circuits for describing the properties of films with various structure and stoichiometric composition were proposed. Possibility of conductivity variation of the polycrystalline tin dioxide films as a result of аnnealing in an inert atmosphere was demonstrated by utilizing impedance spectroscopy. Annealing induces the recrystallization of the films, changing in their stoichiometry as well as increase of the sizes of SnO2 crystallites. Variation of electrical conductivity and structure of tin dioxide films as a result of annealing in inert atmosphere was confirmed by X-ray diffraction analysis. Analysis of the impedance diagrams of tin dioxide films was found to be a powerful tool to study their electrical properties. 

  10. Solubility of Sulfur Dioxide in Sulfuric Acid

    Science.gov (United States)

    Chang, K. K.; Compton, L. E.; Lawson, D. D.

    1982-01-01

    The solubility of sulfur dioxide in 50% (wt./wt.) sulfuric acid was evaluated by regular solution theory, and the results verified by experimental measurements in the temperature range of 25 C to 70 C at pressures of 60 to 200 PSIA. The percent (wt./wt.) of sulfur dioxide in 50% (wt./wt.) sulfuric acid is given by the equation %SO2 = 2.2350 + 0.0903P - 0.00026P 10 to the 2nd power with P in PSIA.

  11. A carbon dioxide fatality from dry ice.

    Science.gov (United States)

    Srisont, Smith; Chirachariyavej, Thamrong; Peonim, A V M Vichan

    2009-07-01

    This report documents a rare case of carbon dioxide intoxication in a young healthy male. The deceased hid in a small plastic container, size 1.5 x 1 x 1 m, and within 5 min he was located suffering convulsions and was reported as dead within minutes. Scene investigation revealed dry ice in the container. Autopsy findings were unremarkable. The probable cause of the convulsions was carbon dioxide intoxication due to both the dry ice sublimation and the small confined space in which he was hiding. This report emphasizes the significance of scene investigation in establishing the cause of the death.

  12. Operating reactors licensing actions summary

    International Nuclear Information System (INIS)

    1982-04-01

    The operating reactors licensing actions summary is designed to provide the management of the Nuclear Regulatory Commission (NRC) with an overview of licensing actions dealing with operating power and nonpower reactors. These reports utilize data collected from the Division of Licensing in the Office of Nuclear Reactor Regulation and are prepared by the Office of Management and Program Analysis

  13. Summary of ISNP2K

    Indian Academy of Sciences (India)

    Summary of ISNP2K. 7. New accelerators and new applications. Accelerators are basic facilities for nuclear and particle physics. It is quite impressive to see how new accelerators are being built in India. The super-conducting linac booster for the 15 UD Pelletron accelerator at NSC, New. Delhi was reported by A Roy, NSC.

  14. Biomass energy systems program summary

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-07-01

    Research programs in biomass which were funded by the US DOE during fiscal year 1978 are listed in this program summary. The conversion technologies and their applications have been grouped into program elements according to the time frame in which they are expected to enter the commercial market. (DMC)

  15. Determination of sulfur dioxide by a radiorelease method

    Energy Technology Data Exchange (ETDEWEB)

    Sriman Narayanan, S.; Rao, V.R.S. (Indian Inst. of Tech., Madras. Dept. of Chemistry)

    1983-04-13

    A radiorelease technique for the determination of sulfur dioxide using radiochlor /sup 36/Cl-amine-T is described. Methods for the elimination of interference from coexisting gases are also reported. 1-40 ppm sulfur dioxide can be determined.

  16. Determination of sulfur dioxide by a radiorelease method

    International Nuclear Information System (INIS)

    Sriman Narayanan, S.; Rao, V.R.S.

    1983-01-01

    A radiorelease technique for the determination of sulfur dioxide using radiochlor 36 Cl-amine-T is described. Methods for the elimination of interference from coexisting gases are also reported. 1-40 ppm sulfur dioxide can be determined. (author)

  17. International Space Station Carbon Dioxide Removal Assembly Testing

    Science.gov (United States)

    Knox, James C.

    2000-01-01

    Performance testing of the International Space Station Carbon Dioxide Removal Assembly flight hardware in the United States Laboratory during 1999 is described. The CDRA exceeded carbon dioxide performance specifications and operated flawlessly. Data from this test is presented.

  18. 40 CFR 180.444 - Sulfur dioxide; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... § 180.444 Sulfur dioxide; tolerances for residues. A tolerance is established as follows for sulfite residues of the fungicide sulfur dioxide (determined as (SO2)) in or on the following raw agricultural... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Sulfur dioxide; tolerances for...

  19. 21 CFR 868.5310 - Carbon dioxide absorber.

    Science.gov (United States)

    2010-04-01

    ... breathing circuit as a container for carbon dioxide absorbent. It may include a canister and water drain. (b... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Carbon dioxide absorber. 868.5310 Section 868.5310...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5310 Carbon dioxide absorber. (a...

  20. 49 CFR 179.102-1 - Carbon dioxide, refrigerated liquid.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Carbon dioxide, refrigerated liquid. 179.102-1...) § 179.102-1 Carbon dioxide, refrigerated liquid. (a) Tank cars used to transport carbon dioxide, refrigerated liquid must comply with the following special requirements: (1) All plates for tank, manway nozzle...

  1. 40 CFR 89.322 - Carbon dioxide analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Carbon dioxide analyzer calibration... Test Equipment Provisions § 89.322 Carbon dioxide analyzer calibration. (a) Prior to its introduction... carbon dioxide analyzer shall be calibrated on all normally used instrument ranges. New calibration...

  2. 40 CFR 86.1324-84 - Carbon dioxide analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Carbon dioxide analyzer calibration... Exhaust Test Procedures § 86.1324-84 Carbon dioxide analyzer calibration. Prior to its introduction into service and monthly thereafter, the NDIR carbon dioxide analyzer shall be calibrated as follows: (a...

  3. 40 CFR 86.124-78 - Carbon dioxide analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Carbon dioxide analyzer calibration... Complete Heavy-Duty Vehicles; Test Procedures § 86.124-78 Carbon dioxide analyzer calibration. Prior to its introduction into service and monthly thereafter the NDIR carbon dioxide analyzer shall be calibrated: (a...

  4. 40 CFR 86.524-78 - Carbon dioxide analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Carbon dioxide analyzer calibration... Regulations for 1978 and Later New Motorcycles; Test Procedures § 86.524-78 Carbon dioxide analyzer calibration. (a) Prior to its introduction into service and monthly thereafter the NDIR carbon dioxide...

  5. 40 CFR 90.320 - Carbon dioxide analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Carbon dioxide analyzer calibration... Emission Test Equipment Provisions § 90.320 Carbon dioxide analyzer calibration. (a) Prior to its initial... carbon dioxide analyzer as follows: (1) Follow good engineering practices for instrument start-up and...

  6. 40 CFR 91.320 - Carbon dioxide analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Carbon dioxide analyzer calibration... Provisions § 91.320 Carbon dioxide analyzer calibration. (a) Prior to its introduction into service, and monthly thereafter, or within one month prior to the certification test, calibrate the NDIR carbon dioxide...

  7. Array of titanium dioxide nanostructures for solar energy utilization

    Science.gov (United States)

    Qiu, Xiaofeng; Parans Paranthaman, Mariappan; Chi, Miaofang; Ivanov, Ilia N; Zhang, Zhenyu

    2014-12-30

    An array of titanium dioxide nanostructures for solar energy utilization includes a plurality of nanotubes, each nanotube including an outer layer coaxial with an inner layer, where the inner layer comprises p-type titanium dioxide and the outer layer comprises n-type titanium dioxide. An interface between the inner layer and the outer layer defines a p-n junction.

  8. Carbon dioxide: making the right connection

    African Journals Online (AJOL)

    During the changeover of machines, the patient was manually ventilated with a ... Fearing residual contamination of the new machine with volatile agents, an ICU .... Grey with black-and-white shoulder. High-pressure air. Salmon pink. Carbon dioxide. Green. Green with grey shoulder. Medical vacuum. Primrose yellow.

  9. Piezomagnetism and magnetoelastic memory in uranium dioxide.

    Science.gov (United States)

    Jaime, M; Saul, A; Salamon, M; Zapf, V S; Harrison, N; Durakiewicz, T; Lashley, J C; Andersson, D A; Stanek, C R; Smith, J L; Gofryk, K

    2017-07-24

    The thermal and magnetic properties of uranium dioxide, a prime nuclear fuel and thoroughly studied actinide material, remain a long standing puzzle, a result of strong coupling between magnetism and lattice vibrations. The magnetic state of this cubic material is characterized by a 3-k non-collinear antiferromagnetic structure and multidomain Jahn-Teller distortions, likely related to its anisotropic thermal properties. Here we show that single crystals of uranium dioxide subjected to strong magnetic fields along threefold axes in the magnetic state exhibit the abrupt appearance of positive linear magnetostriction, leading to a trigonal distortion. Upon reversal of the field the linear term also reverses sign, a hallmark of piezomagnetism. A switching phenomenon occurs at ±18 T, which persists during subsequent field reversals, demonstrating a robust magneto-elastic memory that makes uranium dioxide the hardest piezomagnet known. A model including a strong magnetic anisotropy, elastic, Zeeman, Heisenberg exchange, and magnetoelastic contributions to the total energy is proposed.The nuclear fuel uranium dioxide is of intrinsic interest due to its industrial applications but it also exhibits intriguing electronic and magnetic properties. Here, the authors demonstrate how its complex magnetic structure and interactions give rise to a strong piezomagnetic effect.

  10. 21 CFR 173.300 - Chlorine dioxide.

    Science.gov (United States)

    2010-04-01

    ...) The additive may be used as an antimicrobial agent in water used to wash fruits and vegetables that.... Treatment of the fruits and vegetables with chlorine dioxide shall be followed by a potable water rinse or... 1 CFR part 51. You may obtain a copy from the Center for Food Safety and Applied Nutrition (HFS-200...

  11. Improved ionic model of liquid uranium dioxide

    NARCIS (Netherlands)

    Gryaznov, [No Value; Iosilevski, [No Value; Yakub, E; Fortov, [No Value; Hyland, GJ; Ronchi, C

    The paper presents a model for liquid uranium dioxide, obtained by improving a simplified ionic model, previously adopted to describe the equation of state of this substance [1]. A "chemical picture" is used for liquid UO2 of stoichiometric and non-stoichiometric composition. Several ionic species

  12. Carbon dioxide therapy in hypocapnic respiratory failure.

    Science.gov (United States)

    Julu, P O O; Shah, M; Monro, J A; Puri, B K

    2018-01-01

    Oxygen therapy, usually administered by a facemask or nasal cannulae, is the current default treatment of respiratory failure. Since respiration entails intake of oxygen and release of carbon dioxide from tissues as waste product, the notion of administering carbon dioxide in respiratory failure appears counter-intuitive. However, carbon dioxide stimulates the chemosensitive area of the medulla, known as the central respiratory chemoreceptor, which activates the respiratory groups of neurones in the brainstem and stimulates inspiration thereby initiating oxygen intake during normal breathing. This vital initiation of normal breathing is via a reduction in the pH of the cerebrospinal fluid and the medullary interstitial fluid. We hypothesise that in cases of type I respiratory failure in which the P a CO 2 is low, administration of carbon dioxide by inhalation would stimulate the respiratory groups of brainstem neurones and facilitate breathing, which would be of therapeutic value. Preliminary clinical evidence in favour of this hypothesis is presented and we recommend that a formal randomised study be carried out. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. 21 CFR 582.3862 - Sulfur dioxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sulfur dioxide. 582.3862 Section 582.3862 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 582.3862...

  14. 21 CFR 182.3862 - Sulfur dioxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sulfur dioxide. 182.3862 Section 182.3862 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 182.3862 Sulfur...

  15. Integrated Vertical Photobioreactor System for Carbon Dioxide ...

    African Journals Online (AJOL)

    A vertical photobioreactor containing the microalgae Scenedesmus obliquus is a highly efficient system for converting carbon dioxide (CO2) into biomass. The use of photobioreactor for CO2 mitigation has been explored using microalgae as photosynthetic microorganism. The growth rate (m, h-1) were 0.03; 0.13; 0.20; 0.09 ...

  16. Tourism Transport, Technology, and Carbon Dioxide Emissions

    NARCIS (Netherlands)

    Peeters, P.M.

    2010-01-01

    Technological development from horse-drawn carriages to the new Airbus A380 has led to a remarkable increase in both the capacity and speed of tourist travel. This development has an endogenous systemic cause and will continue to increase carbon dioxide emissions/energy consumption if left

  17. Carbon dioxide (CO2) utilizing strain database

    African Journals Online (AJOL)

    Jane

    2011-10-17

    Oct 17, 2011 ... CSD can be used to gain information related to CO2 fixing microbes. It can also contribute to devising biological strategies for reducing carbon dioxide from the environment. It introduces an innovative idea of exploring the potential of these bacterial strains for reversing global warming. The CSD can be.

  18. Electrocatalytic carbon dioxide reduction - a mechanistic study

    NARCIS (Netherlands)

    Schouten, Klaas Jan Schouten

    2013-01-01

    This thesis presents new insights into the reduction of carbon dioxide to methane and ethylene on copper electrodes. This electrochemical process has great potential for the storage of surplus renewable electrical energy in the form of hydrocarbons. The research described in this thesis focuses on

  19. Heat transfer coeffcient for boiling carbon dioxide

    DEFF Research Database (Denmark)

    Knudsen, Hans Jørgen Høgaard; Jensen, Per Henrik

    1997-01-01

    Heat transfer coefficient and pressure drop for boiling carbon dioxide (R744) flowing in a horizontal pipe has been measured. The pipe is heated by condensing R22 outside the pipe. The heat input is supplied by an electrical heater wich evaporates the R22. With the heat flux assumed constant over...

  20. Heat transfer coefficient for boiling carbon dioxide

    DEFF Research Database (Denmark)

    Knudsen, Hans Jørgen Høgaard; Jensen, Per Henrik

    1998-01-01

    Heat transfer coefficient and pressure drop for boiling carbon dioxide (R744) flowing in a horizontal pipe has been measured. The calculated heat transfer coeeficient has been compared with the Chart correlation of Shah. The Chart Correlation predits too low heat transfer coefficient but the ratio...

  1. Dissolved carbon dioxide in Dutch coastal waters

    NARCIS (Netherlands)

    Bakker, D.C E; de Baar, H.J.W.; de Wilde, H.P.J.

    1996-01-01

    The role of shelf seas in global carbon cycling is poorly understood. The dissolved inorganic carbon system and air-sea exchange of carbon dioxide (CO2) are described for the Dutch coastal zone in September 1993. The inorganic carbon chemistry was affected by tidal mixing, wind speed, wind

  2. Carbon dioxide capture and air quality

    NARCIS (Netherlands)

    Horssen, A. van; Ramirez, C.A.; Harmelen, T. van; Koornneef, J.

    2011-01-01

    Carbon dioxide (CO2) is one of the most important greenhouse gases (GHG). The most dominant source of anthropogenic CO2 contributing to the rise in atmospheric concentration since the industrial revolution is the combustion of fossil fuels. These emissions are expected to result in global climate

  3. RETENTION OF SULFUR DIOXIDE BY NYLON FILTERS

    Science.gov (United States)

    Based on laboratory studies, recovery efficiencies of sulfur dioxide (SO2) were determined for nylon filters. The nylon filters used in these experiments were found to retain SO2. A relatively uniform amount (1.7%) was recoverable from each nylon filter, independent of relative...

  4. Yellow cake to ceramic uranium dioxide

    International Nuclear Information System (INIS)

    Zawidzki, T.W.; Itzkovitch, I.J.

    1983-01-01

    This overview article first reviews the processes for converting uranium ore concentrates to ceramic uranium dioxide at the Port Hope Refinery of Eldorado Resources Limited. In addition, some of the problems, solutions, thoughts and research direction with respect to the production and properties of ceramic UO 2 are described

  5. Electrowinning molten titanium from titanium dioxide

    CSIR Research Space (South Africa)

    Van Vuuren, DS

    2005-10-01

    Full Text Available The value chain of titanium products shows that the difference between the cost of titanium ingot and titanium dioxide is about $9/kg titanium. In contrast, the price of aluminium, which is produced in a similar way, is only about $1.7/kg...

  6. Thermal Oxidation of Structured Silicon Dioxide

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lehrmann; Hansen, Ole; Jensen, Jørgen Arendt

    2014-01-01

    The topography of thermally oxidized, structured silicon dioxide is investigated through simulations, atomic force microscopy, and a proposed analytical model. A 357 nm thick oxide is structured by removing regions of the oxide in a masked etch with either reactive ion etching or hydrofluoric acid...

  7. Carbon dioxide sensing with sulfonated polyaniline

    NARCIS (Netherlands)

    Doan, D.C.T.; Ramaneti, R.; Baggerman, J.; Bent, van der J.; Marcelis, A.T.M.; Tong, H.D.; Rijn, van C.J.M.

    2012-01-01

    The use of polyaniline and especially sulfonated polyaniline (SPAN) is explored for sensing carbon dioxide (CO2) at room temperature. Frequency-dependent AC measurements were carried out to detect changes in impedance of the polymer, drop casted on interdigitated electrodes, when exposed to CO2 gas.

  8. Bicontinuous nanoporous polymers by carbon dioxide foaming

    NARCIS (Netherlands)

    Krause, B.; Münüklü, P.; van der Vegt, N.F.A.; Wessling, Matthias; Sijbesma, H.P.

    2001-01-01

    We investigate the physical foaming process of glassy poly(ether imide) and poly(ether sulfone) using carbon dioxide and report temperature-concentration diagrams ("foam diagrams") marking out the foaming envelope in which dense CO2-saturated films expand and microvoids are introduced. Two types of

  9. U.S. Annual Climatological Summaries

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Annual Climatological Summary contains historical monthly and annual summaries for over 8000 U.S. locations. Observing stations are located in the United States of...

  10. Systematic framework for carbon dioxide capture and utilization processes to reduce the global carbon dioxide emissions

    DEFF Research Database (Denmark)

    Frauzem, Rebecca; Plaza, Cristina Calvera; Gani, Rafiqul

    In the year 2013, 9.5 billion metric tons of carbon dioxide gas was emitted into the air, and each year this amount is increasing [1]. Carbon dioxide emissions are of particular concern as they represent 80% of greenhouse gas emissions and therefore are a large contributor to global warming. Amon...... framework with its implemented methods and tools is a small but important step. Collaboration and integration of data, methods and tools is necessary to provide a more sustainable solution to the global carbon dioxide emission problem.......In the year 2013, 9.5 billion metric tons of carbon dioxide gas was emitted into the air, and each year this amount is increasing [1]. Carbon dioxide emissions are of particular concern as they represent 80% of greenhouse gas emissions and therefore are a large contributor to global warming. Among...... which the issue of global carbon dioxide emissions can be investigated in terms of different available capture-utilization technologies, solution methods, and benefit scenarios, with the objective to determine more sustainable solutions within an appropriate application boundary. The framework would...

  11. ENDF/B summary documentation

    International Nuclear Information System (INIS)

    Kinsey, R.

    1979-07-01

    This publication provides a localized source of descriptions for the evaluations contained in the ENDF/B Library. The summary documentation presented is intended to be a more detailed description than the (File 1) comments contained in the computer readable data files, but not so detailed as the formal reports describing each ENDF/B evaluation. The summary documentations were written by the CSEWB (Cross Section Evaluation Working Group) evaluators and compiled by NNDC (National Nuclear Data Center). This edition includes documentation for materials found on ENDF/B Version V tapes 501 to 516 (General Purpose File) excluding tape 504. ENDF/B-V also includes tapes containing partial evaluations for the Special Purpose Actinide (521, 522), Dosimetry (531), Activation (532), Gas Production (533), and Fission Product (541-546) files. The materials found on these tapes are documented elsewhere. Some of the evaluation descriptions in this report contain cross sections or energy level information

  12. Safeguards Summary Event List (SSEL)

    International Nuclear Information System (INIS)

    1991-07-01

    The Safeguards Summary Event List (SSEL) provides brief summaries of several hundred safeguards-related events involving nuclear material or facilities regulated by the US Nuclear Regulatory Commission (NRC). Because of public interest, the Miscellaneous category includes a few events which involve either source material, byproduct material, or natural uranium which are exempt from safeguards requirements. Events are described under the categories of bomb-related, intrusion, missing and/or allegedly stolen, transportation, tampering/vandalism, arson, firearms, radiological sabotage, nonradiological sabotage, pre-1990 alcohol and drugs (involving reactor operators, security force members, or management persons), and miscellaneous. The information contained in the event descriptions is derived primarily from official NRC reporting channels

  13. ENDF/B summary documentation

    Energy Technology Data Exchange (ETDEWEB)

    Kinsey, R. (comp.)

    1979-07-01

    This publication provides a localized source of descriptions for the evaluations contained in the ENDF/B Library. The summary documentation presented is intended to be a more detailed description than the (File 1) comments contained in the computer readable data files, but not so detailed as the formal reports describing each ENDF/B evaluation. The summary documentations were written by the CSEWB (Cross Section Evaluation Working Group) evaluators and compiled by NNDC (National Nuclear Data Center). This edition includes documentation for materials found on ENDF/B Version V tapes 501 to 516 (General Purpose File) excluding tape 504. ENDF/B-V also includes tapes containing partial evaluations for the Special Purpose Actinide (521, 522), Dosimetry (531), Activation (532), Gas Production (533), and Fission Product (541-546) files. The materials found on these tapes are documented elsewhere. Some of the evaluation descriptions in this report contain cross sections or energy level information. (RWR)

  14. Visualizing Summary Statistics and Uncertainty

    KAUST Repository

    Potter, K.

    2010-08-12

    The graphical depiction of uncertainty information is emerging as a problem of great importance. Scientific data sets are not considered complete without indications of error, accuracy, or levels of confidence. The visual portrayal of this information is a challenging task. This work takes inspiration from graphical data analysis to create visual representations that show not only the data value, but also important characteristics of the data including uncertainty. The canonical box plot is reexamined and a new hybrid summary plot is presented that incorporates a collection of descriptive statistics to highlight salient features of the data. Additionally, we present an extension of the summary plot to two dimensional distributions. Finally, a use-case of these new plots is presented, demonstrating their ability to present high-level overviews as well as detailed insight into the salient features of the underlying data distribution. © 2010 The Eurographics Association and Blackwell Publishing Ltd.

  15. Separations innovative concepts: Project summary

    Energy Technology Data Exchange (ETDEWEB)

    Lee, V.E. (ed.)

    1988-05-01

    This project summary includes the results of 10 innovations that were funded under the US Department's Innovative Concept Programs. The concepts address innovations that can substantially reduce the energy used in industrial separations. Each paper describes the proposed concept, and discusses the concept's potential energy savings, market applications, technical feasibility, prior work and state of the art, and future development needs.

  16. Compact Visualisation of Video Summaries

    Directory of Open Access Journals (Sweden)

    Janko Ćalić

    2007-01-01

    Full Text Available This paper presents a system for compact and intuitive video summarisation aimed at both high-end professional production environments and small-screen portable devices. To represent large amounts of information in the form of a video key-frame summary, this paper studies the narrative grammar of comics, and using its universal and intuitive rules, lays out visual summaries in an efficient and user-centered way. In addition, the system exploits visual attention modelling and rapid serial visual presentation to generate highly compact summaries on mobile devices. A robust real-time algorithm for key-frame extraction is presented. The system ranks importance of key-frame sizes in the final layout by balancing the dominant visual representability and discovery of unanticipated content utilising a specific cost function and an unsupervised robust spectral clustering technique. A final layout is created using an optimisation algorithm based on dynamic programming. Algorithm efficiency and robustness are demonstrated by comparing the results with a manually labelled ground truth and with optimal panelling solutions.

  17. Moriond QCD 2013 Experimental Summary

    Energy Technology Data Exchange (ETDEWEB)

    Denisov, Dmitri [Fermilab

    2013-06-28

    The article presents experimental highlights of Moriond 2013 QCD conference. This was fantastic conference and the first Moriond QCD since the discovery of the Higgs boson. Many new results about its properties have been presented at the conference with Higgs-like particle becoming a Higgs as it properties match expected for the Higgs boson pretty well. There were many new results presented in all experimental areas including QCD, elecroweak, studies of the top, bottom and charm quarks, searches for physics beyond Standard Model as well as studies of the heavy ion collisions. 56 experimental talks have been presented at the conference and it is impossible to cover each result in the summary, so highlights are limited to what I was able to present in my summary talk presented on March 16 2013. The proceedings of the conference cover in depth all talks presented and I urge you to get familiar with all of them. Theoretical Summary of the conference was given by Michelangelo Mangano, so theory talks are not covered in the article.

  18. Summary

    Indian Academy of Sciences (India)

    In explaining this, we determine spin (frequency) of black holes which is a parameter of our model. For the best observational fit, we obtain the spin parameter of black holes ranges: 0.6 ≤ a ≤ 0.8: None of them corresponds to an extremally (a~1) rotating black hole. This is a test of Einstein's theory of General Relativity.

  19. Summary

    International Nuclear Information System (INIS)

    Roehlig, Klaus-Juergen

    2014-01-01

    Document available in abstract form only. Full text follows: During the five sessions of the workshop, much insight has been gained in a variety of issues and challenges that national programmes will encounter as they approach the construction phase of deep geologic repositories as well as their plans to address and resolve these issues. Due to the wide range of participating programmes and due to the different phases of repository development represented, the information presented at the workshop ranged from general and generic questions to specific technical, managerial, administrative, legal, regulatory and procedural issues. Although many issues still awaiting their resolutions, it can be observed that there were joint views amongst the participants with respect to the nature and specificities of these issues. These include: - the need for flexibility (within a so-called safety envelope) when projects evolve over time, - the need to address targets could be very difficult in nature and in some cases may compete with each other when developing and optimising repository systems, - the central role of management with regard to developing adequate professional attitudes and an appropriate safety culture, taking into account the various professional disciplines involved, - the need for integrating different legal and regulatory fields, often addressed by different authorities, and the question of a 'leading regulator'; - the technical challenge of conceptualising parallel processes such as excavation in parts of a repository and emplacement in others and the need to fulfil related safety requirements (mining and occupational, radiation protection etc.), - monitoring may have different roles in different phases of repository development, or - the outstanding role of the safety case prepared in advance to operation (waste emplacement) compared to the cases prepared at other stages of repository development, and the need to act accordingly in the regulatory and licensing process. This set of issues is by no means complete. For the Regulators' Forum and the IGSC it is now necessary to identify those issues and approaches to their resolutions which are of joint interest in order to address them in their programmes of work. The IGSC will, in accordance with its mandate, focus on topics related to safety case development and to the links to establish between different components of repository development. Subjects which have to be discussed and perhaps addressed in the Programme of Work include: - Operational safety: In the past, IGSC focussed on the relationship of operational and postclosure safety. A move towards questions specific for operational safety and in particular the potential for developing a list of events, incident causes etc. to be accounted for when assessing operational safety ('operational safety FEP list') will be considered. - Further attention will be devoted to establishing the linkage between the construction of engineered components and safety assessment, i.e. to the issue of feasibility to construct components according to the design specifications made by, or used in, safety assessments. - The IGSC will contribute to the EU MoDerN project in order to address issues related to monitoring and its linkage to safety demonstration. - IGSC also will further address organisational issues. (author)

  20. Summary

    OpenAIRE

    2013-01-01

    This issue of RCCS Annual Review begins with three articles focusing on women, war and violence, and concludes with two texts on creative city policies. The other articles included here present a critical examination of various issues: the dominant trends in homelessness research; the social representations and uses of DNA technology in criminal investigation in Portugal; and the relations between heritage and tourism in the contemporary world.

  1. Summary

    International Nuclear Information System (INIS)

    Bickerton, George

    1997-01-01

    The Chernobyl accident has pushed many countries in analyzing critically their radiological emergency plans in order to identify the fields requiring amelioration or reinforcement. A common topic was the necessity of informing and drilling efficiently the civil population as well as different intervening agents against effects of nuclear accidents. It was stressed that the health and safety of populations, potentially most exposed, constitute a top priority, followed by the protection of food storage. The majority of the countries, were the management of public affairs is effected at two or more echelons, is confronted with the difficulty of developing plans clearly defining the missions and responsibilities of different administration levels as well as the interactions between them in case of emergency. Emphasized are also the requirements of information tools able of computing the contamination of foods or forages taking into account of factors like annual season, the phase of crop growth and the meteorological conditions. Obviously, such programs permit forecasting, surveying and evaluating the contamination and consequently, establishing the proper level of intervention. Also, the question of intervention thresholds was approached as well as the necessity of harmonizing intervention on international scale. A number of topics were mentioned to be under current study among which the relations between soil contamination and radionuclide concentration in milk and forage as well as the methods of managing the highly cesium-contaminated milk. Finally, it was argued for the necessity of ensuring the population confidence in the measures of intervention as well as in the indications of competent officials in charge with emergency actions

  2. Summary

    International Nuclear Information System (INIS)

    2002-01-01

    This report summarizes the progress made that resulted in the improvement of the organizational and analytical performance on Nuclear Analytical Laboratories at the Ankara Nuclear Research and Training Centre in accordance with ISO 17025 requirements. This report lists the main accomplishments and presents future plans of the Laboratory

  3. Summary

    OpenAIRE

    Huetz de Lemps, Xavier

    2017-01-01

    The Spanish colonial bureaucracy in the 19th century Philippines is a good example of the kind of profoundly and incorrigihly corrupt Systems whose capacity to survive, adapt and reproduce is a source of fascination to contemporary observers and historians alike. This book seeks to explore and understand the workings of an administrative machine that nevertheless “held” the archipelago until 1898. Eschewing clichéd idealisations or demonisations of Spanish rule, and eschewing the kind of hist...

  4. SUMMARY

    African Journals Online (AJOL)

    drug was identified in 66.6% of responders and these consisted of. Antihistamines in 54%, corticosteroids in 7.9%, and Vitamin B Complex in 6.3%. Itching with oral CQ occurred in 100% of the responders and in 49% with intramuscular injection ...

  5. Monitoring carbon dioxide in mechanically ventilated patients during hyperbaric treatment

    DEFF Research Database (Denmark)

    Bjerregård, Asger; Jansen, Erik

    2012-01-01

    Measurement of the arterial carbon dioxide (P(a)CO(2)) is an established part of the monitoring of mechanically ventilated patients. Other ways to get information about carbon dioxide in the patient are measurement of end-tidal carbon dioxide (P(ET)CO(2)) and transcutaneous carbon dioxide (PTCCO2......). Carbon dioxide in the blood and cerebral tissue has great influence on vasoactivity and thereby blood volume of the brain. We have found no studies on the correlation between P(ET)CO(2) or P(TC)CO(2), and P(a)CO(2) during hyperbaric oxygen therapy (HBOT)....

  6. Energy efficient solvent regeneration process for carbon dioxide capture

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Shaojun; Meyer, Howard S.; Li, Shiguang

    2018-02-27

    A process for removing carbon dioxide from a carbon dioxide-loaded solvent uses two stages of flash apparatus. Carbon dioxide is flashed from the solvent at a higher temperature and pressure in the first stage, and a lower temperature and pressure in the second stage, and is fed to a multi-stage compression train for high pressure liquefaction. Because some of the carbon dioxide fed to the compression train is already under pressure, less energy is required to further compress the carbon dioxide to a liquid state, compared to conventional processes.

  7. 31 CFR 26.3 - Availability of Environmental Impact Assessment Summaries (EIA Summaries) and Environmental...

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Availability of Environmental Impact Assessment Summaries (EIA Summaries) and Environmental Impact Assessments (EIAs). 26.3 Section 26.3 Money and... DEVELOPMENT BANDS (MDBs) § 26.3 Availability of Environmental Impact Assessment Summaries (EIA Summaries) and...

  8. Research Progress in Carbon Dioxide Storage and Enhanced Oil Recovery

    Science.gov (United States)

    Wang, Keliang; Wang, Gang; Lu, Chunjing

    2018-02-01

    With the rapid development of global economy, human beings have become highly dependent upon fossil fuel such as coal and petroleum. Much fossil fuel is consumed in industrial production and human life. As a result, carbon dioxide emissions have been increasing, and the greenhouse effects thereby generated are posing serious threats to environment of the earth. These years, increasing average global temperature, frequent extreme weather events and climatic changes cause material disasters to the world. After scientists’ long-term research, ample evidences have proven that emissions of greenhouse gas like carbon dioxide have brought about tremendous changes to global climate. To really reduce carbon dioxide emissions, governments of different countries and international organizations have invested much money and human resources in performing research related to carbon dioxide emissions. Manual underground carbon dioxide storage and carbon dioxide-enhanced oil recovery are schemes with great potential and prospect for reducing carbon dioxide emissions. Compared with other schemes for reducing carbon dioxide emissions, aforementioned two schemes exhibit high storage capacity and yield considerable economic benefits, so they have become research focuses for reducing carbon dioxide emissions. This paper introduces the research progress in underground carbon dioxide storage and enhanced oil recovery, pointing out the significance and necessity of carbon dioxide-driven enhanced oil recovery.

  9. Uranium Dioxide Powder Flow ability Improvement Using Sol-Gel

    International Nuclear Information System (INIS)

    Juanda, D.; Sambodo Daru, G.

    1998-01-01

    The improvement of flow ability characteristics of uranium dioxide powder has been done using sol-gel process. To anticipate a pellet mass production with uniform pellet dimension, the uranium dioxide powder must be have a spherical form. Uranium dioxide spherical powder has been diluted in acid transformed into sol colloidal solution. To obtain uranium dioxide spherical form, the uranium sol-colloidal solution has been dropped in a hot paraffin ( at the temperature of 90 0 C) to form gelatinous colloid and then dried at 800 0 C, and sintered at the temperature of 1700 0 C. The flow ability of spherical uranium dioxide powder has been examined by using Flowmeter Hall (ASTM. B. 213-46T). The measurement result reveals that the spherical uranium dioxide powder has a flow ability twice than that of unprocessed uranium dioxide powder

  10. Carbon dioxide conversion over carbon-based nanocatalysts.

    Science.gov (United States)

    Khavarian, Mehrnoush; Chai, Siang-Piao; Mohamed, Abdul Rahman

    2013-07-01

    The utilization of carbon dioxide for the production of valuable chemicals via catalysts is one of the efficient ways to mitigate the greenhouse gases in the atmosphere. It is known that the carbon dioxide conversion and product yields are still low even if the reaction is operated at high pressure and temperature. The carbon dioxide utilization and conversion provides many challenges in exploring new concepts and opportunities for development of unique catalysts for the purpose of activating the carbon dioxide molecules. In this paper, the role of carbon-based nanocatalysts in the hydrogenation of carbon dioxide and direct synthesis of dimethyl carbonate from carbon dioxide and methanol are reviewed. The current catalytic results obtained with different carbon-based nanocatalysts systems are presented and how these materials contribute to the carbon dioxide conversion is explained. In addition, different strategies and preparation methods of nanometallic catalysts on various carbon supports are described to optimize the dispersion of metal nanoparticles and catalytic activity.

  11. Carbon Dioxide and Nitrogen Infused Compressed Air Foam for Depopulation of Caged Laying Hens

    Science.gov (United States)

    Gurung, Shailesh; White, Dima; Archer, Gregory; Styles, Darrel; Zhao, Dan; Farnell, Yuhua; Byrd, James; Farnell, Morgan

    2018-01-01

    Simple Summary Compressed air, detergent, and water make up compressed air foam. Our laboratory has previously reported that compressed air foam may be an effective method for mass depopulation of caged layer hens. Gases, such as carbon dioxide and nitrogen, have also been used for poultry euthanasia and depopulation. The objective of this study was to produce compressed air foam infused with carbon dioxide or nitrogen to compare its efficacy against foam with air and gas inhalation methods (carbon dioxide or nitrogen) for depopulation of caged laying hens. The study showed that a carbon dioxide-air mixture or 100% nitrogen can replace air to make compressed air foam. However, the foam with carbon dioxide had poor foam quality compared to the foam with air or nitrogen. The physiological stress response of hens subjected to foam treatments with and without gas infusion did not differ significantly. Hens exposed to foam with nitrogen died earlier as compared to methods such as foam with air and carbon dioxide. The authors conclude that infusion of nitrogen into compressed air foam results in better foam quality and shortened time to death as compared to the addition of carbon dioxide. Abstract Depopulation of infected poultry flocks is a key strategy to control and contain reportable diseases. Water-based foam, carbon dioxide inhalation, and ventilation shutdown are depopulation methods available to the poultry industry. Unfortunately, these methods have limited usage in caged layer hen operations. Personnel safety and welfare of birds are equally important factors to consider during emergency depopulation procedures. We have previously reported that compressed air foam (CAF) is an alternative method for depopulation of caged layer hens. We hypothesized that infusion of gases, such as carbon dioxide (CO2) and nitrogen (N2), into the CAF would reduce physiological stress and shorten time to cessation of movement. The study had six treatments, namely a negative control

  12. Magnesian calcite sorbent for carbon dioxide capture

    Energy Technology Data Exchange (ETDEWEB)

    Mabry, J.C.; Mondal, K. [Southern Illinois University, Carbondale, IL (United States)

    2011-07-01

    Magnesian calcite with controlled properties was synthesized for the removal of carbon dioxide. The results from characterization, reactivity and CO{sub 2} capture capacity for different synthesis conditions are reported. The magnesian calcite samples (CaCO{sub 3}:MgCO{sub 3}) were synthesized by the coprecipitation of specific amounts of commercially available CaO and MgO by carbon dioxide. Characterization was done with BET, SEM/EDS, particle size analysis and XRD. The capacity was measured using TGA cycles at 800 {sup o}C and compared for different preparation conditions. The effects of CaO, MgO and surfactant loading on the physical properties and carbonation activity were studied to determine the optimal synthesis condition. A long-term carbonation-calcination cycling test was conducted on the optimal sample. It was observed that the sample maintained its capacity to 86% of its original uptake even after 50 cycles.

  13. Anthropogenic sulfur dioxide emissions: 1850–2005

    Directory of Open Access Journals (Sweden)

    S. J. Smith

    2011-02-01

    Full Text Available Sulfur aerosols impact human health, ecosystems, agriculture, and global and regional climate. A new annual estimate of anthropogenic global and regional sulfur dioxide emissions has been constructed spanning the period 1850–2005 using a bottom-up mass balance method, calibrated to country-level inventory data. Global emissions peaked in the early 1970s and decreased until 2000, with an increase in recent years due to increased emissions in China, international shipping, and developing countries in general. An uncertainty analysis was conducted including both random and systemic uncertainties. The overall global uncertainty in sulfur dioxide emissions is relatively small, but regional uncertainties ranged up to 30%. The largest contributors to uncertainty at present are emissions from China and international shipping. Emissions were distributed on a 0.5° grid by sector for use in coordinated climate model experiments.

  14. Sulfur Dioxide Emissions from Congo Volcanoes

    Science.gov (United States)

    2002-01-01

    The Earth Probe Total Ozone Mapping Spectrometer (TOMS) detected a sulfur dioxide cloud associated with the January 2002 eruption of Nyiragongo as it flew over the region at around 11 a.m. local time (0900 UTC) on January 17. The sensor detected no significant amounts of ash in the eruption cloud. At the time of the TOMS overpass the cloud extended up to roughly 200 km (124 miles) northwest of Nyiragongo and was still attached to the volcano. This observation is consistent with nearly coincident MODIS imagery which shows an opaque cloud of gas and steam in the same location. The TOMS measurements show that the amount of sulfur dioxide in the Nyiragongo's plume range from about 10 to 30 kilotons. Please note that TOMS mass retrievals are dependent on the altitude of the cloud and may be adjusted as more information becomes available. Since the cloud may still have been developing at the time of the TOMS overpass, the final sulfur dioxide burden may have been greater. Wind trajectory data (courtesy of Leslie Lait, SSAI) suggest that part of the cloud may have reached at least mid- to upper-tropospheric altitudes of up to 12 km (7 miles), but scientists suspect no significant stratospheric injection of sulfur dioxide as a result of this eruption since the gas was not visible over the Democratic Republic of the Congo region in subsequent TOMS data acquired on January 18. Production of sulfur dioxide without a significant ash cloud is commonly observed during effusive eruptions such as the Nyiragongo event. Although dense low-level ash may be produced during such eruptions, these particulates usually fall out fairly quickly and elude detection by satellite. The size of the January 17 Nyiragongo cloud and the estimated sulfur dioxide tonnage are fairly modest, and at least an order of magnitude smaller than values typically measured by TOMS during eruptions of nearby Nyamuragira during its frequent outbursts (e.g., on February 6, 2001). Sulfur dioxide column amounts

  15. Thermal properties of nonstoichiometry uranium dioxide

    Science.gov (United States)

    Kavazauri, R.; Pokrovskiy, S. A.; Baranov, V. G.; Tenishev, A. V.

    2016-04-01

    In this paper, was developed a method of oxidation pure uranium dioxide to a predetermined deviation from the stoichiometry. Oxidation was carried out using the thermogravimetric method on NETZSCH STA 409 CD with a solid electrolyte galvanic cell for controlling the oxygen potential of the environment. 4 samples uranium oxide were obtained with a different ratio of oxygen-to-metal: O / U = 2.002, O / U = 2.005, O / U = 2.015, O / U = 2.033. For the obtained samples were determined basic thermal characteristics of the heat capacity, thermal diffusivity, thermal conductivity. The error of heat capacity determination is equal to 5%. Thermal diffusivity and thermal conductivity of the samples decreased with increasing deviation from stoichiometry. For the sample with O / M = 2.033, difference of both values with those of stoichiometric uranium dioxide is close to 50%.

  16. The climate report 2001. Executive summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-03-01

    The Climate Report 2001 present all policies and measures adopted in the energy sector in order to fulfill the commitment in United Nations Framework convention on Climate Change. Sweden's energy and carbon dioxide taxation policy is the most effective measure for reducing carbon dioxide emissions, although other measures intended to encourage the efficiency of energy use and the use of renewable energy also contributes. It is expected that, as a result of the various incentive programmes, carbon dioxide emissions will have been reduced by 3-4 million tonnes by 2000/2005, of which a significant part will have been reduced in other countries. Taxation policy has decreased emissions with approximately 5 million tonnes in 2000. Until 2010, it is expected that carbon dioxide emissions will be essentially unchanged at the 1990 level. Until 2020 emissions will rise depending on nuclear power phaseout.

  17. Titanium Dioxide Photocatalysis in Biomaterials Applications

    OpenAIRE

    Cai, Yanling

    2013-01-01

    Despite extensive preventative efforts, the problem of controlling infections associated with biomedical materials persists. Bacteria tend to colonize on biocompatible materials and form biofilms; thus, novel biomaterials with antibacterial properties are of great interest. In this thesis, titanium dioxide (TiO2)-associated photocatalysis under ultraviolet (UV) irradiation was investigated as a strategy for developing bioactivity and antibacterial properties on biomaterials. Although much of ...

  18. Structure of zirconium dioxide based porous glasses

    Czech Academy of Sciences Publication Activity Database

    Gubanova, N. N.; Kopitsa, G. P.; Ezdakova, K. V.; Baranchikov, A. Y.; Angelov, Borislav; Feoktystov, A.; Pipich, V.; Ryukhtin, Vasyl; Ivanov, V. K.

    2014-01-01

    Roč. 8, č. 5 (2014), s. 967-975 ISSN 1027-4510 R&D Projects: GA ČR GAP208/10/1600; GA MŠk(XE) LM2011019; GA ČR GB14-36566G Institutional support: RVO:61389013 ; RVO:61389005 Keywords : zirconium dioxide * porous glasse * nanoparticles Subject RIV: CF - Physical ; Theoretical Chemistry; BG - Nuclear, Atomic and Molecular Physics, Colliders (UJF-V) Impact factor: 0.359, year: 2012

  19. Pulsed discharge plasmas in supercritical carbon dioxide

    OpenAIRE

    Kiyan, Tsuyoshi; Uemura, A.; Tanaka, K.; Zhang, C.H.; Namihira, Takao; Sakugawa, Takashi; Katsuki, Sunao; Akiyama, Hidenori; Roy, B.C.; Sasaki, M.; Goto, M.; キヤン, ツヨシ; ナミヒラ, タカオ; サクガワ, タカシ; カツキ, スナオ

    2005-01-01

    In recent years, several studies about electrical discharge plasma in supercritical carbon dioxide (CO2) have been carried out. One of the unique characteristics of supercritical fluid is a large density fluctuation near the critical point that can result in marked dramatic changes of thermal conductivity. Therefore, the electrical discharge plasma produced in supercritical fluid has unique features and reactions unlike those of normal plasma produced in gas phase. In our experiments, two typ...

  20. Anodic growth of titanium dioxide nanostructures

    DEFF Research Database (Denmark)

    2010-01-01

    Disclosed is a method of producing nanostructures of titanium dioxide (TiO 2 ) by anodisation of titanium (Ti) in an electrochemical cell, comprising the steps of: immersing a non-conducting substrate coated with a layer of titanium, defined as the anode, in an electrolyte solution...... an electrical contact to the layer of titanium on the anode, where the electrical contact is made in the electrolyte solution...

  1. Plutonium focus area: Technology summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    To ensure research and development programs focus on the most pressing environmental restoration and waste management problems at the U.S. Department of Energy (DOE), the Assistant Secretary for the Office of Environmental Management (EM) established a working group in August 1993 to implement a new approach to research and technology development. As part of this approach, EM developed a management structure and principles that led to creation of specific focus areas. These organizations were designed to focus scientific and technical talent throughout DOE and the national scientific community on major environmental restoration and waste management problems facing DOE. The focus area approach provides the framework for inter-site cooperation and leveraging of resources on common problems. After the original establishment of five major focus areas within the Office of Technology Development (EM-50), the Nuclear Materials Stabilization Task Group (NMSTG, EM-66) followed EM-50`s structure and chartered the Plutonium Focus Area (PFA). NMSTG`s charter to the PFA, described in detail later in this book, plays a major role in meeting the EM-66 commitments to the Defense Nuclear Facilities Safety Board (DNFSB). The PFA is a new program for FY96 and as such, the primary focus of revision 0 of this Technology Summary is an introduction to the Focus Area; its history, development, and management structure, including summaries of selected technologies being developed. Revision 1 to the Plutonium Focus Area Technology Summary is slated to include details on all technologies being developed, and is currently planned for release in August 1996. The following report outlines the scope and mission of the Office of Environmental Management, EM-60, and EM-66 organizations as related to the PFA organizational structure.

  2. Fusion Plasma Theory project summaries

    International Nuclear Information System (INIS)

    1993-10-01

    This Project Summary book is a published compilation consisting of short descriptions of each project supported by the Fusion Plasma Theory and Computing Group of the Advanced Physics and Technology Division of the Department of Energy, Office of Fusion Energy. The summaries contained in this volume were written by the individual contractors with minimal editing by the Office of Fusion Energy. Previous summaries were published in February of 1982 and December of 1987. The Plasma Theory program is responsible for the development of concepts and models that describe and predict the behavior of a magnetically confined plasma. Emphasis is given to the modelling and understanding of the processes controlling transport of energy and particles in a toroidal plasma and supporting the design of the International Thermonuclear Experimental Reactor (ITER). A tokamak transport initiative was begun in 1989 to improve understanding of how energy and particles are lost from the plasma by mechanisms that transport them across field lines. The Plasma Theory program has actively-participated in this initiative. Recently, increased attention has been given to issues of importance to the proposed Tokamak Physics Experiment (TPX). Particular attention has been paid to containment and thermalization of fast alpha particles produced in a burning fusion plasma as well as control of sawteeth, current drive, impurity control, and design of improved auxiliary heating. In addition, general models of plasma behavior are developed from physics features common to different confinement geometries. This work uses both analytical and numerical techniques. The Fusion Theory program supports research projects at US government laboratories, universities and industrial contractors. Its support of theoretical work at universities contributes to the office of Fusion Energy mission of training scientific manpower for the US Fusion Energy Program

  3. Fusion Plasma Theory project summaries

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    This Project Summary book is a published compilation consisting of short descriptions of each project supported by the Fusion Plasma Theory and Computing Group of the Advanced Physics and Technology Division of the Department of Energy, Office of Fusion Energy. The summaries contained in this volume were written by the individual contractors with minimal editing by the Office of Fusion Energy. Previous summaries were published in February of 1982 and December of 1987. The Plasma Theory program is responsible for the development of concepts and models that describe and predict the behavior of a magnetically confined plasma. Emphasis is given to the modelling and understanding of the processes controlling transport of energy and particles in a toroidal plasma and supporting the design of the International Thermonuclear Experimental Reactor (ITER). A tokamak transport initiative was begun in 1989 to improve understanding of how energy and particles are lost from the plasma by mechanisms that transport them across field lines. The Plasma Theory program has actively-participated in this initiative. Recently, increased attention has been given to issues of importance to the proposed Tokamak Physics Experiment (TPX). Particular attention has been paid to containment and thermalization of fast alpha particles produced in a burning fusion plasma as well as control of sawteeth, current drive, impurity control, and design of improved auxiliary heating. In addition, general models of plasma behavior are developed from physics features common to different confinement geometries. This work uses both analytical and numerical techniques. The Fusion Theory program supports research projects at US government laboratories, universities and industrial contractors. Its support of theoretical work at universities contributes to the office of Fusion Energy mission of training scientific manpower for the US Fusion Energy Program.

  4. Plutonium focus area: Technology summary

    International Nuclear Information System (INIS)

    1996-03-01

    To ensure research and development programs focus on the most pressing environmental restoration and waste management problems at the U.S. Department of Energy (DOE), the Assistant Secretary for the Office of Environmental Management (EM) established a working group in August 1993 to implement a new approach to research and technology development. As part of this approach, EM developed a management structure and principles that led to creation of specific focus areas. These organizations were designed to focus scientific and technical talent throughout DOE and the national scientific community on major environmental restoration and waste management problems facing DOE. The focus area approach provides the framework for inter-site cooperation and leveraging of resources on common problems. After the original establishment of five major focus areas within the Office of Technology Development (EM-50), the Nuclear Materials Stabilization Task Group (NMSTG, EM-66) followed EM-50's structure and chartered the Plutonium Focus Area (PFA). NMSTG's charter to the PFA, described in detail later in this book, plays a major role in meeting the EM-66 commitments to the Defense Nuclear Facilities Safety Board (DNFSB). The PFA is a new program for FY96 and as such, the primary focus of revision 0 of this Technology Summary is an introduction to the Focus Area; its history, development, and management structure, including summaries of selected technologies being developed. Revision 1 to the Plutonium Focus Area Technology Summary is slated to include details on all technologies being developed, and is currently planned for release in August 1996. The following report outlines the scope and mission of the Office of Environmental Management, EM-60, and EM-66 organizations as related to the PFA organizational structure

  5. Fusion plasma theory project summaries

    Science.gov (United States)

    1993-10-01

    This Project Summary book is a published compilation consisting of short descriptions of each project supported by the Fusion Plasma Theory and Computing Group of the Advanced Physics and Technology Division of the Department of Energy, Office of Fusion Energy. The summaries contained in this volume were written by the individual contractors with minimal editing by the Office of Fusion Energy. Previous summaries were published in February of 1982 and December of 1987. The Plasma Theory program is responsible for the development of concepts and models that describe and predict the behavior of a magnetically confined plasma. Emphasis is given to the modelling and understanding of the processes controlling transport of energy and particles in a toroidal plasma and supporting the design of the International Thermonuclear Experimental Reactor (ITER). A tokamak transport initiative was begun in 1989 to improve understanding of how energy and particles are lost from the plasma by mechanisms that transport them across field lines. The Plasma Theory program has actively participated in this initiative. Recently, increased attention has been given to issues of importance to the proposed Tokamak Physics Experiment (TPX). Particular attention has been paid to containment and thermalization of fast alpha particles produced in a burning fusion plasma as well as control of sawteeth, current drive, impurity control, and design of improved auxiliary heating. In addition, general models of plasma behavior are developed from physics features common to different confinement geometries. This work uses both analytical and numerical techniques. The Fusion Theory program supports research projects at U.S. government laboratories, universities and industrial contractors. Its support of theoretical work at universities contributes to the office of Fusion Energy mission of training scientific manpower for the U.S. Fusion Energy Program.

  6. Carbon dioxide in Arctic and subarctic regions

    Energy Technology Data Exchange (ETDEWEB)

    Gosink, T. A.; Kelley, J. J.

    1981-03-01

    A three year research project was presented that would define the role of the Arctic ocean, sea ice, tundra, taiga, high latitude ponds and lakes and polar anthropogenic activity on the carbon dioxide content of the atmosphere. Due to the large physical and geographical differences between the two polar regions, a comparison of CO/sub 2/ source and sink strengths of the two areas was proposed. Research opportunities during the first year, particularly those aboard the Swedish icebreaker, YMER, provided additional confirmatory data about the natural source and sink strengths for carbon dioxide in the Arctic regions. As a result, the hypothesis that these natural sources and sinks are strong enough to significantly affect global atmospheric carbon dioxide levels is considerably strengthened. Based on the available data we calculate that the whole Arctic region is a net annual sink for about 1.1 x 10/sup 15/ g of CO/sub 2/, or the equivalent of about 5% of the annual anthropogenic input into the atmosphere. For the second year of this research effort, research on the seasonal sources and sinks of CO/sub 2/ in the Arctic will be continued. Particular attention will be paid to the seasonal sea ice zones during the freeze and thaw periods, and the tundra-taiga regions, also during the freeze and thaw periods.

  7. Carbon dioxide embolism during laparoscopic sleeve gastrectomy

    Directory of Open Access Journals (Sweden)

    Amir Abu Zikry

    2011-01-01

    Full Text Available Bariatric restrictive and malabsorptive operations are being carried out in most countries laparoscopically. Carbon dioxide or gas embolism has never been reported in obese patients undergoing bariatric surgery. We report a case of carbon dioxide embolism during laparoscopic sleeve gastrectomy (LSG in a young super obese female patient. Early diagnosis and successful management of this complication are discussed. An 18-year-old super obese female patient with enlarged fatty liver underwent LSG under general anesthesia. During initial intra-peritoneal insufflation with CO 2 at high flows through upper left quadrant of the abdomen, she had precipitous fall of end-tidal CO 2 and SaO 2 % accompanied with tachycardia. Early suspicion led to stoppage of further insufflation. Clinical parameters were stabilized after almost 30 min, while the blood gas analysis was restored to normal levels after 1 h. The area of gas entrainment on the damaged liver was recognized by the surgeon and sealed and the surgery was successfully carried out uneventfully. Like any other laparoscopic surgery, carbon dioxide embolism can occur during bariatric laparoscopic surgery also. Caution should be exercised when Veress needle is inserted through upper left quadrant of the abdomen in patients with enlarged liver. A high degree of suspicion and prompt collaboration between the surgeon and anesthetist can lead to complete recovery from this potentially fatal complication.

  8. Carbon dioxide makes heat therapy work

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, H.

    1987-01-01

    Scientists can now propagate healthy blueberry and raspberry plants from virus-infected stock by treating it with heat and carbon dioxide. Plants are grown at 100/sup 0/F, which makes them develop faster than the virus can spread. Then cuttings are taken of the new growth - less than an inch long - and grown into full-sized, virus-free plants. But in this race to outdistance the virus, some plant species are not able to take the heat. Some even die. Chemical reactions double for every 14/sup 0/F rise in temperature. So, if you try to grow a plant at 100/sup 0/F that was originally growing at 86/sup 0/F, it will double its respiration rate. Adding carbon dioxide increases the rate of photosynthesis in plants, which increases the plant's food reserves. What carbon dioxide does to allow some plants to grow at temperatures at which they would otherwise not survive and it allows other plants to grow for longer periods at 100/sup 0/F. One problem with the process, says Converse, is that the longer plants are exposed to heat the greater the mutation rate. So, resulting clones should be closely examined for trueness to horticultural type.

  9. Biological effects data: Fluoride and sulfur dioxide

    Energy Technology Data Exchange (ETDEWEB)

    McMechan, K.J. (ed.); Holton, R.L.; Ulbricht, R.J.; Morgan , J.B.

    1975-04-01

    The Alumax Pacific Aluminum Corporation has proposed construction of an aluminum reduction facility near Youngs Bay at Warrenton, Oregon. This report comprises one part of the final report to Alumax on a research project entitled, Physical, Chemical and Biological Studies of Youngs Bay.'' It presents data pertaining to the potential biological effects of fluoride and sulfur dioxide, two potentially hazardous plant-stack emissions, on selected aquatic species of the area. Companion volumes provide a description of the physical characteristics the geochemistry, and the aquatic animals present in Youngs Bay and adjacent ecosystems. An introductory volume provides general information and maps of the area, and summarizes the conclusions of all four studies. The data from the two phases of the experimental program are included in this report: lethal studies on the effects of selected levels of fluoride and sulfur dioxide on the survival rate of eleven Youngs Bay faunal species from four phyla, and sublethal studies on the effects of fluoride and sulfur dioxide on the rate of primary production of phytoplankton. 44 refs., 18 figs., 38 tabs.

  10. Electrocatalytic process for carbon dioxide conversion

    Energy Technology Data Exchange (ETDEWEB)

    Masel, Richard I.; Salehi-Khojin, Amin; Kutz, Robert

    2017-11-14

    An electrocatalytic process for carbon dioxide conversion includes combining a Catalytically Active Element and a Helper Polymer in the presence of carbon dioxide, allowing a reaction to proceed to produce a reaction product, and applying electrical energy to said reaction to achieve electrochemical conversion of said carbon dioxide reactant to said reaction product. The Catalytically Active Element can be a metal in the form of supported or unsupported particles or flakes with an average size between 0.6 nm and 100 nm. The reaction products comprise at least one of CO, HCO.sup.-, H.sub.2CO, (HCO.sub.2).sup.-, H.sub.2CO.sub.2, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup.-, CH.sub.3COOH, C.sub.2H.sub.6, (COOH).sub.2, (COO.sup.-).sub.2, and CF.sub.3COOH.

  11. Summary inside IBM's historic turnaround

    CERN Document Server

    2014-01-01

    This work offers a summary of the book "WHO SAYS ELEPHANTS CAN'T DANCE? Inside IBM's Historic Turnaround" by Louis Gerstner.In nine years as the chairman and CEO of International Business Machine Corporation (IBM), Louis Gerstner brought about a dramatic change in the company's fortunes. When he took charge, IBM was on the verge of extinction as the victim of rapid changes in the computer industry. However, instead of breaking up IBM as most analysts were suggesting, Gerstner and his management team turned the company around and restored it to a position of power and influence within the indu

  12. National stakeholder workshop summary report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    This is a summary of the plenary sessions and small group discussion sessions from the fourth National Stakeholder Workshop sponsored by the DOE Office of Worker and Community Transition held in Atlanta, Georgia on March 13--15, 1996. Topics of the sessions included work force planning and restructuring, worker participation in health and safety, review of actions and commitments, lessons learned in collective bargaining agreements, work force restructuring guidance, work force planning, update on community transition activities. Also included are appendices listing the participants and DOE contacts.

  13. Experimental plasma research project summaries

    International Nuclear Information System (INIS)

    1982-10-01

    The experimental plasma Research Branch has responsibility for developing a broad range of experimental data and new experimental techniques that are required for operating and interpreting present large-scale confinement experiments, and for designing future deuterium-tritium burining facilities. The Branch pursued these objectives by supporting research in DOE laboratories, other Federal laboratories, other Federal laboratories, universities, and private industry. Initiation and renewal of research projects are primarily through submission of unsolicited proposals by these institutions to DOE. Summaries of these projects are given

  14. Summary: Lidar Observations from ADM-Aeolus and EarthCARE-Validation, Study of Long-range Transport of Aerosol and Preparation of a Future Chinese CO2 Lidar Mission

    OpenAIRE

    Lemmerz, Christian; Reitebuch, Oliver; Liu, Jiqiao; Wu, Songhua; Althausen, Dietrich

    2017-01-01

    Summary of status and outlook for the three subprojects: Preparation of Cal/Val of spaceborne Aerosol and Carbon dioxide Detection Lidar (ACDL) by ground-based and airborne sounding instruments observations, Validation of ADM-Aeolus by airborne and ground-based wind lidar observations, and Long-range dust transport and validation using ground-based and satellite lidar observations.

  15. DECOVALEX II PROJECT Executive Summary

    International Nuclear Information System (INIS)

    Jing, L.; Stephansson, O.; Kautsky, F.

    1999-11-01

    DECOVALEX II project started in November 1995 as a continuation of the DECOVALEX I project, which was completed at the end of 1994. The project was initiated by recognising the fact that a proper evaluation of the current capacities of numerical modelling of the coupled T-H-M processes in fractured media is needed not only for small scale, well controlled laboratory test cases such as those studied in DECOVALEX I, but also for less characterised, more complex and realistic in-situ experiments. This executive summary presents the motivation, structure, objectives, approaches, and highlights of the main tasks and main achievements of the DECOVALEX II project from 1995-1999. The main source of the materials came from four technical reports the project prepared by the project Secretariat, which, in turn, were based on numerous progress reports produced by a large number of international research teams over the three and half year period. The editors of this summary, together with the Steering Committee of the DECOVALEX II project, feel very encouraged by the progresses which have been made during the project time and very positive about the usefulness of the achievements reached by the project to the larger international community of scientific research and management of radioactive wastes in different countries. We sincerely hope that continued efforts be made to forward the research carried out in both DECOVALEX I and DECOVALEX II projects so that the disposal of radioactive waste could be managed on a more reliable scientific basis

  16. DECOVALEX II PROJECT Executive Summary

    Energy Technology Data Exchange (ETDEWEB)

    Jing, L.; Stephansson, O. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Civil and Environmental Engineering; Tsang, C.F. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States). Earth Science Div.; Knight, L.J. [United Kingdom Nirex Ltd., Harwell (United Kingdom); Kautsky, F. [Swedish Nuclear Power Inspectorate (SKI), Stockholm (Sweden)

    1999-11-01

    DECOVALEX II project started in November 1995 as a continuation of the DECOVALEX I project, which was completed at the end of 1994. The project was initiated by recognising the fact that a proper evaluation of the current capacities of numerical modelling of the coupled T-H-M processes in fractured media is needed not only for small scale, well controlled laboratory test cases such as those studied in DECOVALEX I, but also for less characterised, more complex and realistic in-situ experiments. This executive summary presents the motivation, structure, objectives, approaches, and highlights of the main tasks and main achievements of the DECOVALEX II project from 1995-1999. The main source of the materials came from four technical reports the project prepared by the project Secretariat, which, in turn, were based on numerous progress reports produced by a large number of international research teams over the three and half year period. The editors of this summary, together with the Steering Committee of the DECOVALEX II project, feel very encouraged by the progresses which have been made during the project time and very positive about the usefulness of the achievements reached by the project to the larger international community of scientific research and management of radioactive wastes in different countries. We sincerely hope that continued efforts be made to forward the research carried out in both DECOVALEX I and DECOVALEX II projects so that the disposal of radioactive waste could be managed on a more reliable scientific basis.

  17. Swiss Energy Perspectives 2035 - Management summary; Energieperspektiven 2035 - Management summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-01-15

    This management summary issued by the Swiss Federal Office of Energy (SFOE) summarises the Swiss Energy Perspectives 2035 - a five-part synthesis report published in 2007. The report presents no prognoses but provides an 'if-then' overview of a set of four scenarios that examined ways in which Swiss energy demands could be met by the year 2035. National and international boundary conditions taken into account are reviewed and the four scenarios are introduced and briefly described. These include the reference scenario 'Business as Usual', 'Increased Co-operation' between politics and business, 'New Priorities' with goals set to reduce energy consumption and CO{sub 2} emissions and 'On the Way to a 2000-Watt Society'. Risks posed and chances provided are discussed, as are the options for taking action

  18. Method of immobilizing carbon dioxide from gas streams

    International Nuclear Information System (INIS)

    Holladay, D.W.; Haag, G.L.

    1979-01-01

    This invention comprises a method for rapidly and continuously immobilizing carbon dioxide contained in various industrial off-gas streams, the carbon dioxide being immobilized as dry, stable, and substantially water-insoluble particulates. Briefly, the method comprises passing the gas stream through a fixed or fluidized bed of hydrated barium hydroxide to remove and immobilize the carbon dioxide by converting the bed to barium carbonate. The method has several important advantages: it can be conducted effectively at ambient temperature; it provides a very rapid reaction rate over a wide range of carbon dioxide concentrations; it provides high decontamination factors; and it has a high capacity for carbon dioxide. The invention is especially well suited for the removal of radioactive carbon dioxide from off-gases generated by nuclear-fuel reprocessing facilities and nuclear power plants

  19. The carbon dioxide thermometer and the cause of global warming

    International Nuclear Information System (INIS)

    Calder, Nigel

    1999-01-01

    Carbon dioxide in the air may be increasing because the world is warming. This possibility, which contradicts the hypothesis of an enhanced greenhouse warming driven by manmade emissions, is here pursued in two ways. First, increments in carbon dioxide are treated as readings of a natural thermometer that tracks global and hemispheric temperature deviations, as gauged by meteorologists' thermometers. Calibration of the carbon dioxide thermometer to conventional temperatures then leads to a history of carbon dioxide since 1856 that diverges from the ice-core record. Secondly, the increments of carbon dioxide can also be accounted for, without reference to temperature, by the combined effects of cosmic rays, El Nino and volcanoes. The most durable effect is due to cosmic rays. A solar wind history, used as a long-term proxy for the cosmic rays, gives a carbon dioxide history similar to that inferred from the global temperature deviations. (author)

  20. Changes in plasma potassium concentration during carbon dioxide pneumoperitoneum

    DEFF Research Database (Denmark)

    Perner, A; Bugge, K; Lyng, K M

    1999-01-01

    Hyperkalaemia with ECG changes had been noted during prolonged carbon dioxide pneumoperitoneum in pigs. We have compared plasma potassium concentrations during surgery in 11 patients allocated randomly to undergo either laparoscopic or open appendectomy and in another 17 patients allocated randomly...... to either carbon dioxide pneumoperitoneum or abdominal wall lifting for laparoscopic colectomy. Despite an increasing metabolic acidosis, prolonged carbon dioxide pneumoperitoneum resulted in only a slight increase in plasma potassium concentrations, which was both statistically and clinically insignificant...

  1. Capacitance‐Assisted Sustainable Electrochemical Carbon Dioxide Mineralisation

    OpenAIRE

    Lamb, Katie J.; Dowsett, Mark R.; Chatzipanagis, Konstantinos; Scullion, Zhan Wei; Kröger, Roland; Lee, James D.; Aguiar, Pedro M.; North, Michael; Parkin, Alison

    2017-01-01

    Abstract An electrochemical cell comprising a novel dual‐component graphite and Earth‐crust abundant metal anode, a hydrogen producing cathode and an aqueous sodium chloride electrolyte was constructed and used for carbon dioxide mineralisation. Under an atmosphere of 5 % carbon dioxide in nitrogen, the cell exhibited both capacitive and oxidative electrochemistry at the anode. The graphite acted as a supercapacitive reagent concentrator, pumping carbon dioxide into aqueous solution as hydrog...

  2. Capacitance-Assisted Sustainable Electrochemical Carbon Dioxide Mineralisation

    OpenAIRE

    Lamb, Katie J.; Dowsett, Mark R.; Chatzipanagis, Konstantinos; Scullion, Zhan Wei; Kröger, Roland; Lee, James D.; Aguiar, Pedro M.; North, Michael; Parkin, Alison

    2018-01-01

    An electrochemical cell comprising a novel dual-component graphite and Earth-crust abundant metal anode, a hydrogen producing cathode and an aqueous sodium chloride electrolyte was constructed and used for carbon dioxide mineralisation. Under an atmosphere of 5 % carbon dioxide in nitrogen, the cell exhibited both capacitive and oxidative electrochemistry at the anode. The graphite acted as a supercapacitive reagent concentrator, pumping carbon dioxide into aqueous solution as hydrogen carbon...

  3. Supercritical carbon dioxide: a solvent like no other

    Directory of Open Access Journals (Sweden)

    Jocelyn Peach

    2014-08-01

    Full Text Available Supercritical carbon dioxide (scCO2 could be one aspect of a significant and necessary movement towards green chemistry, being a potential replacement for volatile organic compounds (VOCs. Unfortunately, carbon dioxide has a notoriously poor solubilising power and is famously difficult to handle. This review examines attempts and breakthroughs in enhancing the physicochemical properties of carbon dioxide, focusing primarily on factors that impact solubility of polar and ionic species and attempts to enhance scCO2 viscosity.

  4. Adverse effects of the automotive industry on carbon dioxide emissions

    OpenAIRE

    Mpho Bosupeng

    2016-01-01

    This study aims to determine the effects of the automotive industry on carbon dioxide emissions for the period from 1997 to 2010 for diverse economies, as well as the relationships between carbon dioxide discharges and output. The study applies cointegration and causality tests to validate these associations. The results of the Johansen cointegration test depict long-run associations between the quantity of passenger cars and carbon dioxide emissions in France, Sweden, Spain, Hungary and Japa...

  5. On reaction of titanium polonides with carbon dioxide

    International Nuclear Information System (INIS)

    Abakumov, A.S.; Malyshev, M.L.; Reznikova, N.F.

    1986-01-01

    The reaction between titanium polonides and carbon dioxide has been studied by comparing titanium polonide thermal resistance in vacuum and in carbon dioxide. The investigation has shown that titanium mono- and semipolonides fail at temperatures below 350 deg C. Temperature dependence of polonium vapor pressure prepared at failure of the given polonides is determined by the radiotensiometry in carbon dioxide. Enthalpy calculated for this dependence is close to the enthalpy of elementary polonium evaporation in vacuum

  6. Solid State Lighting OLED Manufacturing Roundtable Summary

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2010-03-31

    Summary of a meeting of OLED experts to develop proposed priority tasks for the Manufacturing R&D initiative, including task descriptions, discussion points, recommendations, and presentation highlights.

  7. Solid State Lighting LED Manufacturing Roundtable Summary

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2010-03-31

    Summary of a meeting of LED experts to develop proposed priority tasks for the Manufacturing R&D initiative, including task descriptions, discussion points, recommendations, and presentation highlights.

  8. Changes in plasma potassium concentration during carbon dioxide pneumoperitoneum

    DEFF Research Database (Denmark)

    Perner, A; Bugge, K; Lyng, K M

    1999-01-01

    Hyperkalaemia with ECG changes had been noted during prolonged carbon dioxide pneumoperitoneum in pigs. We have compared plasma potassium concentrations during surgery in 11 patients allocated randomly to undergo either laparoscopic or open appendectomy and in another 17 patients allocated randomly...... to either carbon dioxide pneumoperitoneum or abdominal wall lifting for laparoscopic colectomy. Despite an increasing metabolic acidosis, prolonged carbon dioxide pneumoperitoneum resulted in only a slight increase in plasma potassium concentrations, which was both statistically and clinically insignificant....... Thus hyperkalaemia is unlikely to develop in patients with normal renal function undergoing carbon dioxide pneumoperitoneum for laparoscopic surgery....

  9. Effects of Elevated Carbon Dioxide on Litter Chemistry and Decomposition

    Data.gov (United States)

    National Aeronautics and Space Administration — The results of published and unpublished experiments investigating the impacts of elevated carbon dioxide on the chemistry (nitrogen and lignin concentration) of...

  10. Effects of Elevated Carbon Dioxide on Litter Chemistry and Decomposition

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: The results of published and unpublished experiments investigating the impacts of elevated carbon dioxide on the chemistry (nitrogen and lignin...

  11. Carbon dioxide absorbent and method of using the same

    Science.gov (United States)

    Perry, Robert James; O'Brien, Michael Joseph

    2014-06-10

    In accordance with one aspect, the present invention provides a composition which contains the amino-siloxane structures I, or III, as described herein. The composition is useful for the capture of carbon dioxide from process streams. In addition, the present invention provides methods of preparing the amino-siloxane composition. Another aspect of the present invention provides methods for reducing the amount of carbon dioxide in a process stream employing the amino-siloxane compositions of the invention, as species which react with carbon dioxide to form an adduct with carbon dioxide.

  12. Carbon dioxide absorbent and method of using the same

    Energy Technology Data Exchange (ETDEWEB)

    Perry, Robert James; O' Brien, Michael Joseph

    2015-12-29

    In accordance with one aspect, the present invention provides a composition which contains the amino-siloxane structures I, or III, as described herein. The composition is useful for the capture of carbon dioxide from process streams. In addition, the present invention provides methods of preparing the amino-siloxane composition. Another aspect of the present invention provides methods for reducing the amount of carbon dioxide in a process stream employing the amino-siloxane compositions of the invention, as species which react with carbon dioxide to form an adduct with carbon dioxide.

  13. Summary of longitudinal instabilities workshop

    Energy Technology Data Exchange (ETDEWEB)

    Chasman, R.

    1976-01-01

    A five-day ISABELLE workshop on longitudinal instabilities was held at Brookhaven, August 9-13, 1976. About a dozen outside accelerator experts, both from Europe and the U.S.A., joined the local staff for discussions of longitudinal instabilities in ISABELLE. An agenda of talks was scheduled for the first day of the workshop. Later during the week, a presentation was given on the subject ''A more rigorous treatment of Landau damping in longitudinal beam instabilities''. A few progress meetings were held in which disagreements regarding calculations of coupling impedances were clarified. A summary session was held on the last day. Heavy emphasis was put on single bunched beam instabilities in the microwave region extending above the cut-off frequency of the ISABELLE vacuum chamber.

  14. CNA/CNS conference summaries

    International Nuclear Information System (INIS)

    1992-01-01

    This volume contains summaries of papers presented at the 32. annual conference of the Canadian Nuclear Association and the 13. annual conference of the Canadian Nuclear Society. The full proceedings, and the individual papers contained therein, have been abstracted separately. Sessions on the following topics are included: Plenary; The international CANDU program; Canadian used fuel management program; Public information advocates; Fuel and electricity supply; In which direction should reactors advance?; Canadian advanced nuclear research program; International cooperation in operations; Safety in design, operation, regulation; Renovation of operating stations; Reactor physics; New concepts and Technology; Fuel behaviour; Reactor design; Safety analysis; Fuel channel behaviour; Equipment and design qualification; Compliance and licensing; Fusion science and technology; Darlington assessment; Plant aging and life assessment; Thermalhydraulic modelling and analysis; Diagnostics and data management; Operator training and certification

  15. Atmospheric carbon dioxide and the climate record

    Energy Technology Data Exchange (ETDEWEB)

    Ellsaesser, H.W.

    1989-04-01

    This paper is an attempt to provide a summary review of conclusions from previous studies on this subject. Subject headings include: conceptualization of the greenhouse effect, the climatic effect of doubled CO/sub 2/, interpretation of the climatic record, diagnosis of apparent and possible model deficiencies, and the palaeoclimatic record.

  16. Atmospheric carbon dioxide and the climate record

    International Nuclear Information System (INIS)

    Ellsaesser, H.W.

    1989-04-01

    This paper is an attempt to provide a summary review of conclusions from previous studies on this subject. Subject headings include: conceptualization of the greenhouse effect, the climatic effect of doubled CO 2 , interpretation of the climatic record, diagnosis of apparent and possible model deficiencies, and the palaeoclimatic record

  17. Summary of presentations and discussions

    International Nuclear Information System (INIS)

    Takeuchi, Mitsuo

    2008-01-01

    In December 2007, the Forum on Stakeholder Confidence discussed its theme entitled 'Link between research, development and demonstration (RD and D) and stakeholder confidence'. It was remarked that regulators need a technical demonstration to aid in evaluating the safety case. Local stakeholders appreciate the opportunity to visualise technological arrangements. In both cases, demonstration adds to confidence in the feasibility of solutions. Some believe there is an important role for analogues in communication with stakeholders, if handled with integrity. To explore and benchmark current practices, it was decided to hold a topical session at the 9. regular meeting of the FSC on 4 June 2008 regarding the use of analogues for confidence building. The session opened with an introductory presentation by the session rapporteur. This incorporated input provided for the purpose by FSC members in cooperation with their country's representative to the NEA RWMC 'Integration Group on the Safety Case'. Three speakers then presented the various uses of analogues by implementers, regulators and scientists to build their own confidence; a fourth speaker dealt with the experience of using natural analogues in public information. The presentations addressed the use of analogues in the field of geological disposal of high-level waste (HLW) and long-lived intermediate level (ILW-LL) radioactive waste. Then the FSC participants split into two working groups for discussion. The outcome of these discussions was reported in plenary on 6 June 2008 and it was agreed to publish proceedings of the session. The present summary, prepared by the session rapporteur with input from the NEA Secretariat, captures the main points heard in the course of the event. It combines data from the formal presentations and remarks made in discussion. The latter represent viewpoints expressed by a group whose primary focus is not natural analogues but rather stakeholder interests. The

  18. Recent Progress and Novel Applications in Enzymatic Conversion of Carbon Dioxide

    Directory of Open Access Journals (Sweden)

    Nguyen Van Duc Long

    2017-04-01

    Full Text Available Turning carbon dioxide (CO2 into fuels and chemicals using chemical, photochemical, electrochemical, and enzymatic methods could be used to recycle large quantities of carbon. The enzymatic method, which is inspired by cellular CO2 metabolism, has attracted considerable attention for efficient CO2 conversion due to improved selectivity and yields under mild reaction conditions. In this review, the research progress of green and potent enzymatic conversion of CO2 into useful fuels and chemicals was discussed. Furthermore, applications of the enzymatic conversion of CO2 to assist in CO2 capture and sequestration were highlighted. A summary including the industrial applications, barriers, and some perspectives on the research and development of the enzymatic approach to convert CO2 were introduced.

  19. Near-Term Opportunities for Carbon Dioxide Capture and Storage 2007

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    This document contains the summary report of the workshop on global assessments for near-term opportunities for carbon dioxide capture and storage (CCS), which took place on 21-22 June 2007 in Oslo, Norway. It provided an opportunity for direct dialogue between concerned stakeholders in the global effort to accelerate the development and commercialisation of CCS technology. This is part of a series of three workshops on near-term opportunities for this important mitigation option that will feed into the G8 Plan of Action on Climate Change, Clean Energy and Sustainable Development. The ultimate goal of this effort is to present a report and policy recommendations to the G8 leaders at their 2008 summit meeting in Japan.

  20. Killing wild geese with carbon dioxide or a mixture of carbon dioxide and argon

    NARCIS (Netherlands)

    Gerritzen, M.A.; Reimert, H.G.M.; Lourens, A.; Bracke, M.B.M.; Verhoeven, M.T.W.

    2013-01-01

    The killing of animals is the subject of societal and political debate. Wild geese are caught and killed on a regular basis for fauna conservation and damage control. Killing geese with carbon dioxide (CO2) is commonly practiced, but not listed in legislation on the protection of flora and fauna,

  1. Pyrochemical reduction of uranium dioxide and plutonium dioxide by lithium metal

    International Nuclear Information System (INIS)

    Usami, T.; Kurata, M.; Inoue, T.; Sims, H.E.; Beetham, S.A.; Jenkins, J.A.

    2002-01-01

    The lithium reduction process has been developed to apply a pyrochemical recycle process for oxide fuels. This process uses lithium metal as a reductant to convert oxides of actinide elements to metal. Lithium oxide generated in the reduction would be dissolved in a molten lithium chloride bath to enhance reduction. In this work, the solubility of Li 2 O in LiCl was measured to be 8.8 wt% at 650 deg. C. Uranium dioxide was reduced by Li with no intermediate products and formed porous metal. Plutonium dioxide including 3% of americium dioxide was also reduced and formed molten metal. Reduction of PuO 2 to metal also occurred even when the concentration of lithium oxide was just under saturation. This result indicates that the reduction proceeds more easily than the prediction based on the Gibbs free energy of formation. Americium dioxide was also reduced at 1.8 wt% lithium oxide, but was hardly reduced at 8.8 wt%

  2. Possibilities of surface coating for thermal insulation. [zirconium dioxide, titanium dioxide, and zircon coatings

    Science.gov (United States)

    Poeschel, E.; Weisser, G.

    1979-01-01

    Calculations performed for pulsating heat sources indicate a relatively thin (200-1000 micron) coating can lower temperature both inside and on the surface of a construction material. Various coating materials (including zirconium dioxide) are discussed, together with possible thermic stresses and ways to deal with the latter.

  3. Capture of carbon dioxide by hybrid sorption

    Science.gov (United States)

    Srinivasachar, Srivats

    2014-09-23

    A composition, process and system for capturing carbon dioxide from a combustion gas stream. The composition has a particulate porous support medium that has a high volume of pores, an alkaline component distributed within the pores and on the surface of the support medium, and water adsorbed on the alkaline component, wherein the proportion of water in the composition is between about 5% and about 35% by weight of the composition. The process and system contemplates contacting the sorbent and the flowing gas stream together at a temperature and for a time such that some water remains adsorbed in the alkaline component when the contact of the sorbent with the flowing gas ceases.

  4. The carbon dioxide capture and geological storage

    International Nuclear Information System (INIS)

    2006-06-01

    This road-map proposes by the Group Total aims to inform the public on the carbon dioxide capture and geological storage. One possible means of climate change mitigation consists of storing the CO 2 generated by the greenhouse gases emission in order to stabilize atmospheric concentrations. This sheet presents the CO 2 capture from lage fossil-fueled combustion installations, the three capture techniques and the CO 2 transport options, the geological storage of the CO 2 and Total commitments in the domain. (A.L.B.)

  5. Nuclear power and carbon dioxide free automobiles

    International Nuclear Information System (INIS)

    Pendergast, D.R.

    1999-01-01

    Nuclear energy has been developed as a major source of electric power in Canada. Electricity from nuclear energy already avoids the emission of about 100 million tonnes of carbon dioxide to the atmosphere in Canada. This is a significant fraction of the 619 million tonnes of Canadian greenhouse gas emissions in 1995. However, the current scope of application of electricity to end use energy needs in Canada limits the contribution nuclear energy can make to carbon dioxide emission reduction. Nuclear energy can also contribute to carbon dioxide emissions reduction through expansion of the use of electricity to less traditional applications. Transportation, in particular contributed 165 million tonnes of carbon dioxide to the Canadian atmosphere in 1995. Canada's fleet of personal vehicles consisted of 16.9 million cars and light trucks. These vehicles were driven on average 21,000 km/year and generated 91 million tonnes of greenhouse gases expressed as a C02 equivalent. Technology to improve the efficiency of cars is under development which is expected to increase the energy efficiency from the 1995 level of about 10 litres/100 km of gasoline to under 3 litres/100km expressed as an equivalent referenced to the energy content of gasoline. The development of this technology, which may ultimately lead to the practical implementation of hydrogen as a portable source of energy for transportation is reviewed. Fuel supply life cycle greenhouse gas releases for several personal vehicle energy supply systems are then estimated. Very substantial reductions of greenhouse gas emissions are possible due to efficiency improvements and changing to less carbon intensive fuels such as natural gas. C02 emissions from on board natural gas fueled versions of hybrid electric cars would be decreased to approximately 25 million t/year from the current 91 million tonnes/year. The ultimate reduction identified is through the use of hydrogen fuel produced via electricity from CANDU power

  6. Method for Extracting and Sequestering Carbon Dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Rau, Gregory H.; Caldeira, Kenneth G.

    2005-05-10

    A method and apparatus to extract and sequester carbon dioxide (CO2) from a stream or volume of gas wherein said method and apparatus hydrates CO2, and reacts the resulting carbonic acid with carbonate. Suitable carbonates include, but are not limited to, carbonates of alkali metals and alkaline earth metals, preferably carbonates of calcium and magnesium. Waste products are metal cations and bicarbonate in solution or dehydrated metal salts, which when disposed of in a large body of water provide an effective way of sequestering CO2 from a gaseous environment.

  7. Carbon dioxide disposal on the ocean floor

    International Nuclear Information System (INIS)

    Giavarini, C.; Maccioni, F.

    2001-01-01

    A lot of experts propose to dispose of the Co2 in the Oceans; but there is some confusion on that subject. The possibility of dispersing the Carbon Dioxide on the Ocean floor must be considered with great caution, carefully studying all the possible balances Co2 is subject to. A parameter which must be considered is the possibility for Co2 - whatever the form may be - of solving in the sea water, even when very deep. At the moment, the most safe way of storing the Co2 in the oceans seems to be the introduction of Co2 Hydrates into the sediments under the ocean floor [it

  8. Nuclear energy significantly reduces carbon dioxide emissions

    International Nuclear Information System (INIS)

    Koprda, V.

    2006-01-01

    This article is devoted to nuclear energy, to its acceptability, compatibility and sustainability. Nuclear energy is non-dispensable part of energy sources with vast innovation potential. The safety of nuclear energy, radioactive waste deposition, and prevention of risk from misuse of nuclear material have to be very seriously adjudged and solved. Nuclear energy is one of the ways how to decrease the contamination of atmosphere with carbon dioxide and it solves partially also the problem of global increase of temperature and climate changes. Given are the main factors responsible for the renaissance of nuclear energy. (author)

  9. Carbon dioxide emissions from Indian monsoonal estuaries

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.; Viswanadham, R.; Rao, G.D.; Prasad, V.R.; Kumar, B; Naidu, S.A.; Kumar, N.A.; Rao, D.B; Sridevi, T.; Krishna, M.S.; Reddy, N.P.C.; Sadhuram, Y.; Murty, T.V.R.

    /CDIAC-74. Frankignoulle, M., G. Abril, A.V. Borges, I. Bourge, C. Canon, B. DeLille, E. Libert, and J.-M. Théate (1998), Carbon dioxide emissions from European estuaries. Science, 282, 434-436. Frankignoulle, M., I. Bourge, R. Wollast (1996). Atmospheric..., and transport of atmospheric CO 2 . Global Biogeochem. Cycles, 23, GB1005, doi :10.1029/2008GB003349. Gupta, G.V.M., V.V.S.S. Sarma, R.S. Robin, A.V. Raman, M. Jai Kumar, M. Rakesh, and B.R. Subramanian (2008). Influence of net ecosystem metabolism...

  10. Nitrogen dioxide exposure studies. Volume 1. Summary of the Gas Research Institute/Harvard indoor air quality and exposure studies on nitrigen dioxide. Topical report, 1985-1994

    Energy Technology Data Exchange (ETDEWEB)

    Spengler, J.D.

    1995-08-10

    This report summarizes the key findings of the studies described in GRI reports Volumes 2-7. The study found that gas-range homes, a gas furnace contributes approximately 8-16 ppb to indoor bedroom NO2 concentrations. In electric-range homes, a gas furnace contributes approximately 2 ppb to indoor levels; a fossilfuel space heater, approx 3 ppb in the winter.

  11. Property Tax Laws of Texas. A Summary.

    Science.gov (United States)

    Howell, Jay D., Jr.

    This booklet is basically a summary of a law book on the same subject by the same author. Although the 25 chapters of the larger work correspond directly to the chapters of the summary, this publication is not a law book in the usual sense. Rather, it is intended primarily to provide a simplified view of the property tax laws of Texas for tax…

  12. Detecting Terrorism Incidence Type from News Summary

    DEFF Research Database (Denmark)

    Nizamani, Sarwat; Memon, Nasrullah

    2012-01-01

    The paper presents the experiments to detect terrorism incidence type from news summary data. We have applied classification techniques on news summary data to analyze the incidence and detect the type of incidence. A number of experiments are conducted using various classification algorithms...... and results show that a simple decision tree classifier can learn incidence type with satisfactory results from news data....

  13. 15 CFR 785.7 - Summary decision.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Summary decision. 785.7 Section 785.7 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE ADDITIONAL PROTOCOL REGULATIONS ENFORCEMENT § 785.7 Summary...

  14. Summary of quantum aspects of gravitation workshop

    Indian Academy of Sciences (India)

    Summary of quantum aspects of gravitation workshop. GHANASHYAM DATE and JNANADEV MAHARANA. The Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai 600 113, India. The Institute of Physics, Sachivalaya Marg, Bhubaneswar 751 005, India. Abstract. This is a summary of the presentations at ...

  15. Theoretical summary talk of QCD 2002

    Indian Academy of Sciences (India)

    This summary will cover the theoretical talks presented at the QCD 2002 meeting held at IIT, Kanpur from November 18–22, 2002. However this talk will not cover the T /= 0 and ρ /= 0 talks as well as discussions of lattice QCD given at the meeting – these will be discussed in the summary by Rajeev Bhalerao. The meeting ...

  16. Methanation of hydrogen and carbon dioxide

    International Nuclear Information System (INIS)

    Burkhardt, Marko; Busch, Günter

    2013-01-01

    Highlights: • The biologic methanation of exclusively gases like hydrogen and carbon dioxide is feasible. • Electrical energy can be stored in the established gas grid by conversion to methane. • The quality of produced biogas is very high (c CH4 = 98 vol%). • The conversion rate is depending on H 2 -flow rate. - Abstract: A new method for the methanation of hydrogen and carbon dioxide is presented. In a novel anaerobic trickle-bed reactor, biochemical catalyzed methanation at mesophilic temperatures and ambient pressure can be realized. The conversion of gaseous substrates by immobilized hydrogenotrophic methanogens is a unique feature of this reactor type. The already patented reactor produces biogas which has a very high quality (c CH4 = 97.9 vol%). Therefore, the storage of biogas in the existing natural gas grid is possible without extensive purification. The specific methane production was measured with P = 1.17 Nm CH4 3 /(m R 3 d). It is conceivable to realize the process at sites that generate solar or wind energy and sites subject to the conditions for hydrogen electrolysis (or other methods of hydrogen production). The combination with conventional biogas plants under hydrogen addition to methane enrichment is possible as well. The process enables the coupling of various renewable energy sources

  17. Studies on carbon dioxide power plant, (3)

    International Nuclear Information System (INIS)

    Akagawa, Koji; Fujii, Terushige; Sakaguchi, Tadashi; Kawabata, Yasusuke; Kuroda, Toshihiro.

    1980-01-01

    A power generating plant using carbon dioxide instead of water has been studied by the authors, as high efficiency can be obtained in high temperature range (higher than 650 deg C) and turbines become compact as compared with the Rankine steam cycle. In this paper, the theoretical analysis of the dynamic characteristics of this small power generating plant of supercritical pressure and the comparison with the experimental results are reported. In the theoretical analysis, the linear approximation method using small variation method was adopted for solution. Every component was modeled as the concentrated constant system, and the transfer function for each component was determined, then simulation was carried out for the total system synthesizing these components. The approximation of physical values, and the analysis of a plunger pump, a regenerator, a heater, a vapor valve, a turbine and a blower, piping, and pressure drop are described. The response to the stepwise changes of heating, flow rate, opening of a vapor valve and a load control valve for a blower was investigated. The theoretical anaysis and the experimental results were in good agreement, and this analysis is applicable to the carbon dioxide plant of practical scale. (Kako, I.)

  18. Metal Insulator transition in Vanadium Dioxide

    Science.gov (United States)

    Jovaini, Azita; Fujita, Shigeji; Suzuki, Akira; Godoy, Salvador

    2012-02-01

    MAR12-2011-000262 Abstract Submitted for the MAR12 Meeting of The American Physical Society Sorting Category: 03.9 (T) On the metal-insulator-transition in vanadium dioxide AZITA JOVAINI, SHIGEJI FUJITA, University at Buffalo, SALVADOR GODOY, UNAM, AKIRA SUZUKI, Tokyo University of Science --- Vanadium dioxide (VO2) undergoes a metal-insulator transition (MIT) at 340 K with the structural change from tetragonal to monoclinic crystal. The conductivity _/ drops at MIT by four orders of magnitude. The low temperature monoclinic phase is known to have a lower ground-state energy. The existence of the k-vector k is prerequisite for the conduction since the k appears in the semiclassical equation of motion for the conduction electron (wave packet). The tetragonal (VO2)3 unit is periodic along the crystal's x-, y-, and z-axes, and hence there is a three-dimensional k-vector. There is a one-dimensional k for a monoclinic crystal. We believe this difference in the dimensionality of the k-vector is the cause of the conductivity drop. Prefer Oral Session X Prefer .

  19. Low temperature sintering of hyperstoichiometric uranium dioxide

    International Nuclear Information System (INIS)

    Chevrel, H.

    1991-12-01

    In the lattice of uranium dioxide with hyperstoichiometric oxygen content (UO 2+x ), each additional oxygen atoms is introduced by shifting two anions from normal sites to interstitial ones, thereby creating two oxygen vacancies. The point defects then combine to form complex defects comprising several interstitials and vacancies. The group of anions (3x) in the interstitial position participate in equilibria promoting the creation of uranium vacancies thereby considerably increasing uranium self-diffusion. However, uranium grain boundaries diffusion governs densification during the first two stages of sintering of uranium dioxide with hyperstoichiometric oxygen content, i.e., up to 93% of the theoretical density. Surface diffusion and evaporation-condensation, which are considerably accentuated by the hyperstoichiometric deviation, play an active role during sintering by promoting crystalline growth during the second and third stages of sintering. U 8 O 8 can be added to adjust the stoichiometry and to form a finely porous structure and thus increase the pore area subjected to surface phenomena. The composition with an O/U ratio equal to 2.25 is found to densify the best, despite a linear growth in sintering activation energy with hyperstoichiometric oxygen content, increasing from 300 kj.mol -1 for UO 2.10 to 440 kJ.mol -1 for UO 2.25 . Seeds can be introduced to obtain original microstructures, for example the presence of large grains in small-grain matrix

  20. Sulfur dioxide converter and pollution arrester system

    International Nuclear Information System (INIS)

    Montalvo, V.H.

    1983-01-01

    A sulphur dioxide converter and pollution arrester system are disclosed which involves the treatment of smoke and/or contaminated air emanating from a combustion area by passage through a zone achieving turbulence into a water spray contained first treating chamber. The turbulence zone, into which an atomized catalyst is introduced, serves to create a longer path for cooling as well as increased centrifugal motion to the solid particles in the contaminated air and also the formation of sulphur trioxide. In other words, the arrangement is such that pollution arresting action is provided in the form of ''slinging'' resulting from tangential directional movement and, when combining with the water spray in the first treating chamber, the ultimate formation of sulphuric acid. Subsequently, the contaminated air, containing amounts of sulphurous and sulphuric acids, passes through a second treating chamber, where airflow throughout the system is occasioned by action at the outlet end, such as the vacuum created by a flue and not by independent mechanical means. The arrangement serves to a twofold purpose, i.e. to minimize or arrest pollution and to convert sulphur dioxide, a component of high sulphur coal, into commercially valuable sulphuric acid

  1. Electronic structure of the actinide dioxides

    International Nuclear Information System (INIS)

    Kelly, P.J.

    1980-03-01

    The electronic properties of the fluorite structured actinide dioxides have been investigated using the linear muffin tin orbital method in the atomic sphere approximation. CaF 2 with the same structure was also studied because of the relative simplicity of its electronic structure and the greater amount of experimental data available. Band structures were calculated both non self consistently and self consistently. In the non self consistent calculations the effect of changing the approximation to the exchange-correlation potential and the starting atomic configurations was examined. Using the concepts of canonical bands the effects of hybridization were investigated. In particular the 5f electrons included in the band picture were found to mix more strongly into the valence band than indicated by experiment. On this basis the 5f electrons were not included in self consistent calculations which in the density functional formalism are capable of yielding ground state properties. Because of the non participation of the f electrons in the bonding UO 2 only was considered as representative of the actinide dioxides. For comparison CaF 2 was also examined. Using Pettifor's pressure formula to determine the equilibrium condition the lattice constants were calculated to be 0.5% and 5% respectively below the experimental values. (author)

  2. Thermo Scientific Sulfur Dioxide Analyzer Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Springston, S. R. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-03-01

    The Sulfur Dioxide Analyzer measures sulfur dioxide based on absorbance of UV light at one wavelength by SO2 molecules which then decay to a lower energy state by emitting UV light at a longer wavelength. Specifically, SO2 + hυ1 →SO2 *→SO2 + hυ2 The emitted light is proportional to the concentration of SO2 in the optical cell. External communication with the analyzer is available through an Ethernet port configured through the instrument network of the AOS systems. The Model 43i-TLE is part of the i-series of Thermo Scientific instruments. The i-series instruments are designed to interface with external computers through the proprietary Thermo Scientific iPort Software. However, this software is somewhat cumbersome and inflexible. BNL has written an interface program in National Instruments LabView that both controls the Model 43i-TLE Analyzer AND queries the unit for all measurement and housekeeping data. The LabView vi (the software program written by BNL) ingests all raw data from the instrument and outputs raw data files in a uniform data format similar to other instruments in the AOS and described more fully in Section 6.0 below.

  3. Nitrogen dioxide (silo gas) poisoning in pigs

    Energy Technology Data Exchange (ETDEWEB)

    Giddens, W.E. Jr.; Whitehair, C.K.; Sleight, S.D.

    1970-10-01

    Investigations were conducted on the composition of silo gas and its effects in pigs which inhale it, and comparison was made of lesions of silo gas toxicosis in pigs and those described for silo-filler's disease in man. Caged pigs were exposed for varying periods to the silo gas by placing them in recently filled silos or within an enclosure formed with plastic sheets at the bottom of a silo chute. Pigs inhaling a high concentration of silo gas for periods longer than 10 minutes died in 21 to 72 minutes. Composition of the silo gas as determined by mass spectrometer analysis was 0.173 to 9.05% carbon dioxide, 0 to 140 p.p.m. of nitric oxide, and 8 to 360 p.p.m. of nitrogen dioxide. In pigs dying from inhaling silo gas, the early lesions were pulmonary alveolar edema and hyperemia. Large amounts of alveolar fibrin were present in pigs that survived the longest. In addition, there were hemorrhage, bronchiolar and bronchial epithelial desquamation, and perivascular, interlobular, and subpleural edema. Pigs surviving the acute effects of silo gas toxicosis did not develop bronchiolitis fibrosa obliterans (BFO) as described for silo-filler's disease in man. 25 references, 5 figures, 2 tables.

  4. Nanomaterial Case Studies: Nanoscale Titanium Dioxide in ...

    Science.gov (United States)

    EPA announced the availability of the final report, Nanomaterial Case Studies: Nanoscale Titanium Dioxide in Water Treatment and in Topical Sunscreen. This report is a starting point to determine what is known and what needs to be known about selected nanomaterials as part of a process to identify and prioritize research to inform future assessments of the potential ecological and health implications of these materials. Two specific applications of nanoscale titanium dioxide (nano-TiO2) are considered: (1) as an agent for removing arsenic from drinking water; and (2) as an active ingredient in topical sunscreen. These case studies are organized around a comprehensive environmental assessment (CEA) framework that combines a product life cycle perspective with the risk assessment paradigm. They are intended to help identify what may need to be known in order to conduct a comprehensive environmental assessment of the potential risks related to nano-TiO2. These “case studies” do not represent completed or even preliminary assessments, nor are they intended to serve as a basis for risk management decisions in the near term on these specific uses of nano TiO2. Rather, the intent is to use this document in developing the scientific and technical information needed for future assessment efforts.

  5. Molecular and physiological responses to titanium dioxide ...

    Science.gov (United States)

    - Changes in tissue transcriptomes and productivity of Arabidopsis thaliana were investigated during exposure of plants to two widely-used engineered metal oxide nanoparticles, titanium dioxide (nano-titanium) and cerium dioxide (nano-cerium). Microarray analyses confirmed that exposure to either nanoparticle altered the transcriptomes of rosette leaves and roots, with comparatively larger numbers of differentially expressed genes (DEGs) found under nano-titania exposure. Nano-titania induced more DEGs in rosette leaves, whereas roots had more DEGs under nano-ceria exposure. MapMan analyses indicated that while nano-titania up-regulated overall and secondary metabolism in both tissues, metabolic processes under nano-ceria remained mostly unchanged. Gene enrichment analysis indicated that both nanoparticles mainly enriched ontology groups such as responses to stress (abiotic and biotic), and defense responses (pathogens), and responses to endogenous stimuli (hormones). Nano-titania specifically induced genes associated with photosynthesis, whereas nano-ceria induced expression of genes related to activating transcription factors, most notably those belonging to the ethylene responsive element binding protein family. Interestingly, there were also increased numbers of rosette leaves and plant biomass under nano-ceria exposure, but not under nano-titania. Other transcriptomic responses did not clearly relate to responses observed at the organism level. This may b

  6. Adaptation to carbon dioxide tax in shipping

    International Nuclear Information System (INIS)

    Olsen, Kristian

    2000-01-01

    This note discusses the consequences for the sea transport sector between Norway and continental Europe of levying a carbon dioxide tax on international bunker. The influence of such a tax on the operational costs of various types of ship and various transport routes is calculated. The profit obtainable from the following ways of adapting to an increased tax level is assessed: (1) Reducing the speed, (2) Rebuilding the engine to decrease fuel consumption, (3) Changing the design speed for new ships. It is found that a carbon dioxide tax of NOK 200 per tonne of CO 2 will increase the transport costs by 3 - 15 percent. In the long run much of this may be transferred to the freight rates since so much of the sea transport are in segments in which the demand for the service is not sensitive to the prices. Even if the freight rates are not changed, a tax this size will not make it necessary to reduce the speed of the existing fleet. The income lost by taking fewer trips will exceed the costs saved in reducing the speed. However, the optimum design speed for new ships may be somewhat reduced (0.5 knots). Rebuilding engines to reduce the fuel consumption would pay off were it not for the fact that the remaining life of the present fleet is probably too short for this to be interesting

  7. Use of supercritical carbon dioxide extraction

    Energy Technology Data Exchange (ETDEWEB)

    Taniguchi, Masayuki (Niigata Univ., Faculty of Engineering, Niigata, (Japan))

    1989-09-25

    Supercritical fluid extraction is a novel diffusion and separation technique which exploits simultaneously the increase of vapor pressure and the difference of chemical affinities of fluids near the critical point. A solvent which is used as the supercritical fluid has the following features: the critical point exists in the position of relatively ease of handling, the solvent is applicable to the extraction of a physiological active substance of thermal instability. Carbon dioxide as the solvent is non-flammable, non-corrosive, non-toxic, cheap, and readily available of high purity. The results of studies on the use of supercritical carbon dioxide (SC-CO{sub 2}) as a solvent for natural products in the fermentation and food industries, were collected. SC-CO{sub 2} extraction are used in many fields, examples for the application are as follows: removal of organic solvents from antibiotics; extraction of vegetable oils contained in wheat germ oil, high quality mustard seeds, rice bran and so on; brewing of sake using rice and rice-koji; use as a non-aqueous medium for the synthesis of precursors of the Aspartame; and use in sterilization. 66 refs., 17 figs., 21 tabs.

  8. MANOVA with Summary Statistics: A STATA Program

    Directory of Open Access Journals (Sweden)

    Nadeem Shafique Butt

    2008-01-01

    Full Text Available Almost all available statistical packages are capable of performing Multivariate Analysis of Variance (MANOVA from raw data. Some of statistical packages have capability to perform independent sample t-test, ANOVA and some other tests of significance on summary data, but you come across not single software that has the capability to perform MANOVA directly on summary data. A STATA programme has been written to perform Multivariate ANOVA on summary data. The programme computes available statistics for Multivariate ANOVA (i.e Willk’s Lembda, Lawley’s-Hotelling trace, Pillae’s trace and Roy’s largest root. The programme is also capable to perform Box–M test for testing equality of covariance matrices on summary data. Example has been given by using the programme on summary data to perform Multivariate ANOVA.

  9. Forum on orthophotography: Summary Report

    Science.gov (United States)

    ,

    1990-01-01

    summaries of the various presentations given by the program participants. The appendixes to the report include a list of forum cosponsoring agencies and cooperating organizations, a summary listing of forum registrants by organizational affiliation, and the forum registration list. Also included in the appendkes is the Higher Resolution Orthophoto Products Survey that was sent to each participant following the forum to assist in the identification of near- and longer-term applications, and the determination of requirements, for higher-resolution orthophoto products.

  10. Bird species richness and densities in relation to sulphur dioxide ...

    African Journals Online (AJOL)

    The expansion of coal-fired power stations in South Africa has resulted in growing environmental concerns as they are the largest emitters of sulphur dioxide (SO2). Sulphur dioxide emissions from power plants pose a potential threat to avian populations. However, the effect of SO2 pollution on bird communities is poorly ...

  11. Interglacials, Milankovitch Cycles, Solar Activity, and Carbon Dioxide

    Directory of Open Access Journals (Sweden)

    Gerald E. Marsh

    2014-01-01

    Full Text Available The existing understanding of interglacial periods is that they are initiated by Milankovitch cycles enhanced by rising atmospheric carbon dioxide concentrations. During interglacials, global temperature is also believed to be primarily controlled by carbon dioxide concentrations, modulated by internal processes such as the Pacific Decadal Oscillation and the North Atlantic Oscillation. Recent work challenges the fundamental basis of these conceptions.

  12. Interglacials, Milankovitch Cycles, Solar Activity, and Carbon Dioxide

    OpenAIRE

    Gerald E. Marsh

    2014-01-01

    The existing understanding of interglacial periods is that they are initiated by Milankovitch cycles enhanced by rising atmospheric carbon dioxide concentrations. During interglacials, global temperature is also believed to be primarily controlled by carbon dioxide concentrations, modulated by internal processes such as the Pacific Decadal Oscillation and the North Atlantic Oscillation. Recent work challenges the fundamental basis of these conceptions.

  13. A sensitive spectrophotometric determination of nitrogen dioxide in ...

    African Journals Online (AJOL)

    In the present investigation, a simple and sensitive spectrophotometric method for the determination of nitrogen dioxide in various environmental samples is described. Nitrogen dioxide in air was fixed as nitrite ion in alkaline sodium arsenite absorbing solution. The nitrite formed was diazotized with paminoacetophenone in ...

  14. Stability of wheat germ oil obtained by supercritical carbon dioxide ...

    African Journals Online (AJOL)

    Wheat germ oil was extracted using an environmental friendly solvent, supercritical carbon dioxide (SCCO2) at a semi-batch flow extraction process. The supercritical carbon dioxide (SC-CO2) extraction was carried out to extract oil at temperature of 40°C and pressure of 25 MPa. Ethanolysis was performed with 1 ...

  15. Applications of Titanium Dioxide Photocatalysis to Construction Materials

    CERN Document Server

    Ohama, Yoshihiko

    2011-01-01

    Titanium dioxide photocatalysis is based on the semiconducting nature of its anatase crystal type. Construction materials with titanium photocatalyst show performances of air purification, self-cleaning, water purification, antibacterial action. This book describes principles of titanium dioxide photocatalysis, its applications to cementitious and noncementitious materials, as well as an overview of standardization of testing methods.

  16. Carbon dioxide (CO 2 ) utilizing strain database | Saini | African ...

    African Journals Online (AJOL)

    The biological means of CO2 fixation using various microorganisms is gaining importance because database of their substantial role in reversing global warming. Carbon dioxide utilizing strain database (CSD) presents a comprehensive overview of microorganisms involved in biological fixation of carbon dioxide. As a part ...

  17. Carbon Dioxide and Global Warming: A Failed Experiment

    Science.gov (United States)

    Ribeiro, Carla

    2014-01-01

    Global warming is a current environmental issue that has been linked to an increase in anthropogenic carbon dioxide in the atmosphere. To raise awareness of the problem, various simple experiments have been proposed to demonstrate the effect of carbon dioxide on the planet's temperature. This article describes a similar experiment, which…

  18. Interaction of carbon dioxide with Cu overlayers on Pt(111)

    DEFF Research Database (Denmark)

    Schumacher, N.; Andersson, Klas Jerker; Grabow, L.C.

    2008-01-01

    Experimental and theoretical studies on the interaction of carbon dioxide with pseudomorphic and rough copper layers deposited on a platinum (111) single crystal are reported. Evidence for carbon dioxide dissociation and carbonate formation is presented and the relevance to methanol synthesis...

  19. Classification of titanium dioxide; Clasificacion del dioxido de titanio

    Energy Technology Data Exchange (ETDEWEB)

    Macias B, L.R. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Garcia C, R.M.; Maya M, M.E. [Secretaria de Hacienda y Credito Publico de Mexico, Mexico (Mexico); Ita T, A. De [Universidad Autonoma Metropolitana Azcapotzalco, Mexico (Mexico); Palacios G, J. [Instituto Politecnico Nacional (Mexico)

    2002-07-01

    In this work the X-ray diffraction (XRD), Scanning Electron Microscopy (Sem) and the X-ray Dispersive Energy Spectroscopy techniques are used with the purpose to achieve a complete identification of phases and mixture of phases of a crystalline material as titanium dioxide. The problem for solving consists of being able to distinguish a sample of titanium dioxide being different than a titanium dioxide pigment. A standard sample of titanium dioxide with NIST certificate is used, which indicates a purity of 99.74% for the TiO{sub 2}. The following way is recommended to proceed: a)To make an analysis by means of X-ray diffraction technique to the sample of titanium dioxide pigment and on the standard of titanium dioxide waiting not find differences. b) To make a chemical analysis by the X-ray Dispersive Energy Spectroscopy via in a microscope, taking advantage of the high vacuum since it is oxygen which is analysed and if it is concluded that the aluminium oxide appears in a greater proportion to 1% it is established that is a titanium dioxide pigment, but if it is lesser then it will be only titanium dioxide. This type of analysis is an application of the nuclear techniques useful for the tariff classification of merchandise which is considered as of difficult recognition. (Author)

  20. Effect of high pressurized carbon dioxide on Escherichia coli ...

    African Journals Online (AJOL)

    Carbon dioxide at high pressure can retard microbial growth and sometimes kill microorganisms depending on values of applied pressure, temperature and exposure time. In this study the effect of high pressurised carbon dioxide (HPCD) on Escherichia coli was investigated. Culture of E. coli was subjected to high ...

  1. 40 CFR 52.1576 - Control strategy: Nitrogen dioxide.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Nitrogen dioxide. 52... strategy: Nitrogen dioxide. (a) The requirements of § 52.14(c)(3) of this chapter as of May 8, 1974 (39 FR 16346), are not met since the plan does not provide for the degree of nitrogen oxides emission reduction...

  2. 40 CFR 86.224-94 - Carbon dioxide analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Carbon dioxide analyzer calibration. 86.224-94 Section 86.224-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.224-94 Carbon dioxide...

  3. 40 CFR 86.1524 - Carbon dioxide analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Carbon dioxide analyzer calibration. 86.1524 Section 86.1524 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Test Procedures § 86.1524 Carbon dioxide analyzer calibration. (a) The calibration requirements for the...

  4. Air quality assessment of carbon monoxide, nitrogen dioxide and ...

    African Journals Online (AJOL)

    Air quality in urban areas is a cause of concern because of increased industrial activities that contribute to large quantities of emissions. The study assess levels and variations of carbon monoxide (CO), nitrogen dioxide (NO2) and sulfur dioxide (SO2) in Blantyre, Malawi using a stationary environmental monitoring station ...

  5. Carbon Dioxide Production in Animal Houses: A literature review

    NARCIS (Netherlands)

    Pedersen, S.; Blanes-Vidal, V.; Joergensen, H.; Chwalibog, A.; Haeussermann, A.; Heetkamp, M.J.W.; Aarnink, A.J.A.

    2008-01-01

    This article deals with carbon dioxide production from farm animals; more specifically, it addresses the possibilities of using the measured carbon dioxide concentration in animal houses as basis for estimation of ventilation flow (as the ventilation flow is a key parameter of aerial emissions from

  6. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Alejandro Lopez-Ortiz; Douglas P. Harrison; Ya Liang

    2001-07-01

    Sodium based sorbents including sodium carbonate may be used to capture carbon dioxide from flue gas. A relatively concentrated carbon dioxide stream may be recoverable for sequestration when the sorbent is regenerated. Electrobalance tests indicated that sodium carbonate monohydrate was formed in a mixture of helium and water vapor at temperatures below 65 C. Additional compounds may also form, but this could not be confirmed. In the presence of carbon dioxide and water vapor, both the initial reaction rate of sodium carbonate with carbon dioxide and water and the sorbent capacity decreased with increasing temperature, consistent with the results from the previous quarter. Increasing the carbon dioxide concentration at constant temperature and water vapor concentration produced a measurable increase in rate, as did increasing the water vapor concentration at constant carbon dioxide concentration and temperature. Runs conducted with a flatter TGA pan resulted in a higher initial reaction rate, presumably due to improved gas-solid contact, but after a short time, there was no significant difference in the rates measured with the different pans. Analyses of kinetic data suggest that the surface of the sodium carbonate particles may be much hotter than the bulk gas due to the highly exothermic reaction with carbon dioxide and water, and that the rate of heat removal from the particle may control the reaction rate. A material and energy balance was developed for a cyclic carbonation/calcination process which captures about 26 percent of the carbon dioxide present in flue gas available at 250 C.

  7. Flexible substrates as basis for photocatalytic reduction of carbon dioxide

    DEFF Research Database (Denmark)

    Jensen, Jacob; Mikkelsen, Mette; Krebs, Frederik C

    2011-01-01

    A photocatalytic system for converting carbon dioxide into carbon monoxide was designed and constructed. The system relies on thin films of the photocatalyst prepared at low temperature using spray coating. We formulated inks based on the well-known photocatalyst titanium dioxide and characterized...

  8. Method for synthesis of titanium dioxide nanotubes using ionic liquids

    Science.gov (United States)

    Qu, Jun; Luo, Huimin; Dai, Sheng

    2013-11-19

    The invention is directed to a method for producing titanium dioxide nanotubes, the method comprising anodizing titanium metal in contact with an electrolytic medium containing an ionic liquid. The invention is also directed to the resulting titanium dioxide nanotubes, as well as devices incorporating the nanotubes, such as photovoltaic devices, hydrogen generation devices, and hydrogen detection devices.

  9. Combined reactions and separations using ionic liquids and carbon dioxide

    NARCIS (Netherlands)

    Kroon, M.C.

    2006-01-01

    A new and general type of process for the chemical industry is presented using ionic liquids and supercritical carbon dioxide as combined reaction and separation media. In this process, the carbon dioxide pressure controls the miscibility of reactants, products, catalyst and ionic liquid, enabling

  10. Kinetics of absorption of carbon dioxide in aqueous piperazine solutions

    NARCIS (Netherlands)

    Derks, P. W. J.; Kleingeld, T.; van Aken, C.; Hogendoorn, J. A.; Versteeg, G. F.

    2006-01-01

    In the present work the absorption of carbon dioxide into aqueous piperazine (PZ) solutions has been studied in a stirred cell, at low to moderate temperatures, piperazine concentrations ranging from 0.6 to 1.5 kmol m- 3, and carbon dioxide pressures up to 500 mbar, respectively. The obtained

  11. Carbon dioxide and nisin act synergistically on Listeria monocytogenes

    DEFF Research Database (Denmark)

    Nilsson, Lilian; Chen, Y.H.; Chikindas, M.L.

    2000-01-01

    This paper examines the synergistic action of carbon dioxide and nisin on Listeria monocytogenes Scott A wild-type and nisin-resistant (Nis(r)) cells grown in broth at 4 degrees C. Carbon dioxide extended the lag phase and decreased the specific growth rate of both strains, but to a greater degree...

  12. Effects of electron beam irradiation on tin dioxide gas sensors

    Indian Academy of Sciences (India)

    In this paper, the effects of electron beam irradiation on the gas sensing performance of tin dioxide thin films toward H2 are studied. The tin dioxide thin films were prepared by ultrasonic spray pyrolysis. The results show that the sensitivity increased after electron beam irradiation. The electron beam irradiation effects on tin ...

  13. Regional Management Plan: Summary report

    International Nuclear Information System (INIS)

    Drobny, N.L.

    1986-01-01

    This summary report describes the results of a 16-month project to develop a Regional Management Plan for low-level radioactive waste management in a seven-state area. The seven states are Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, and Wisconsin. These states have formed the Midwest Interstate Low-Level Radioactive Waste Commission in accord with Congressional requirements established in 1980. What is low-level radioactive waste? Low-level radioactive waste results from the use of radioactive materials in the treatment of disease, the production of consumer goods and industrial products, and from the generation of electricity at nuclear power plants. Low-level wastes, which are a responsibility of the states, are grouped into three classes, A, B, and C; this classification scheme is prescribed by Federal Regulations and represents different degrees of hazard associated with different concentrations of radioactive materials. Class A wastes are the least hazardous. Classes B and C represent higher hazard classes. 14 refs., 13 figs., 9 tabs

  14. Fossil energy program. Summary document

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-05-01

    This program summary document presents a comprehensive overview of the research, development, and demonstration (RD and D) activities that will be performed in FY 1981 by the Assistant Secretary for Fossil Energy (ASFE), US Department of Energy (DOE). The ASFE technology programs for the fossil resources of coal, petroleum (including oil shale) and gas have been established with the goal of making substantive contributions to the nation's future supply and efficienty use of energy. On April 29, 1977, the Administration submitted to Congress the National Energy Plan (NEP) and accompanying legislative proposals designed to establish a coherent energy policy structure for the United States. Congress passed the National Energy Act (NEA) on October 15, 1978, which allows implementation of the vital parts of the NEP. The NEP was supplemented by additional energy policy statements culminating in the President's address on July 15, 1979, presenting a program to further reduce dependence on imported petroleum. The passage of the NEA-related energy programs represent specific steps by the Administration and Congress to reorganize, redirect, and clarify the role of the Federal Government in the formulation and execution of national energy policy and programs. The energy technology RD and D prog4rams carried out by ASFE are an important part of the Federal Government's effort to provide the combination and amounts of energy resources needed to ensure national security and continued economic growth.

  15. Capacitance-Assisted Sustainable Electrochemical Carbon Dioxide Mineralisation.

    Science.gov (United States)

    Lamb, Katie J; Dowsett, Mark R; Chatzipanagis, Konstantinos; Scullion, Zhan Wei; Kröger, Roland; Lee, James D; Aguiar, Pedro M; North, Michael; Parkin, Alison

    2018-01-10

    An electrochemical cell comprising a novel dual-component graphite and Earth-crust abundant metal anode, a hydrogen producing cathode and an aqueous sodium chloride electrolyte was constructed and used for carbon dioxide mineralisation. Under an atmosphere of 5 % carbon dioxide in nitrogen, the cell exhibited both capacitive and oxidative electrochemistry at the anode. The graphite acted as a supercapacitive reagent concentrator, pumping carbon dioxide into aqueous solution as hydrogen carbonate. Simultaneous oxidation of the anodic metal generated cations, which reacted with the hydrogen carbonate to give mineralised carbon dioxide. Whilst conventional electrochemical carbon dioxide reduction requires hydrogen, this cell generates hydrogen at the cathode. Carbon capture can be achieved in a highly sustainable manner using scrap metal within the anode, seawater as the electrolyte, an industrially relevant gas stream and a solar panel as an effective zero-carbon energy source. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  16. Carbon dioxide absorbent and method of using the same

    Energy Technology Data Exchange (ETDEWEB)

    Perry, Robert James [Niskayuna, NY; Lewis, Larry Neil [Scotia, NY; O' Brien, Michael Joseph [Clifton Park, NY; Soloveichik, Grigorii Lev [Latham, NY; Kniajanski, Sergei [Clifton Park, NY; Lam, Tunchiao Hubert [Clifton Park, NY; Lee, Julia Lam [Niskayuna, NY; Rubinsztajn, Malgorzata Iwona [Ballston Spa, NY

    2011-10-04

    In accordance with one aspect, the present invention provides an amino-siloxane composition comprising at least one of structures I, II, III, IV or V said compositions being useful for the capture of carbon dioxide from gas streams such as power plant flue gases. In addition, the present invention provides methods of preparing the amino-siloxane compositions are provided. Also provided are methods for reducing the amount of carbon dioxide in a process stream employing the amino-siloxane compositions of the invention as species which react with carbon dioxide to form an adduct with carbon dioxide. The reaction of the amino-siloxane compositions provided by the present invention with carbon dioxide is reversible and thus, the method provides for multicycle use of said compositions.

  17. Adverse effects of the automotive industry on carbon dioxide emissions

    Directory of Open Access Journals (Sweden)

    Mpho Bosupeng

    2016-05-01

    Full Text Available This study aims to determine the effects of the automotive industry on carbon dioxide emissions for the period from 1997 to 2010 for diverse economies, as well as the relationships between carbon dioxide discharges and output. The study applies cointegration and causality tests to validate these associations. The results of the Johansen cointegration test depict long-run associations between the quantity of passenger cars and carbon dioxide emissions in France, Sweden, Spain, Hungary and Japan. In addition, significant relations were observed between output and carbon dioxide discharges in Spain, Canada, India and Japan. Changes in output had substantial impact on emissions in Germany, Canada and India. The results also show that the number of passenger cars influences the magnitude of emissions in multiple economies. In conclusion, the automotive industry has to be considered in policies that aim to reduce carbon dioxide emissions.

  18. New technology for carbon dioxide at high pressure

    International Nuclear Information System (INIS)

    Hassina, Bazaze; Raouf, Zehioua; Menial, A. H.

    2006-01-01

    Carbon dioxide has long been the nemesis of environmentalists because of its role in global warming, but under just the right conditions-namely, high pressure and high temperature its one of nature's best and most environmentally benign solvents. Decaf-coffee lovers, for instance, benefit from its ability to remove caffeine from coffee beans.During the last few years, carbon dioxide has also made inroads in the dry-cleaning industry, providing a safe cleaning alternative to the chemical perchloroethylene. But it's on the high-tech front that carbon dioxide may make its biggest impact. T here are huge opportunities. Scientists have known for more than a century that at 75 times atmospheric pressure and 31 degree centigrade, carbon dioxide goes into and odd state that chemists called s upercritical . What's interesting to industry is that supercritical carbon dioxide may be an enabling technology for going to smaller dimensions.(Author)

  19. Past explosive outbursts of entrapped carbon dioxide in salt mines provide a new perspective on the hazards of carbon dioxide

    DEFF Research Database (Denmark)

    Hedlund, Frank Huess

    2013-01-01

    . The Menzengraben mine experienced an extreme outburst in 1953, possibly involving a several thousand tons of carbon dioxide. This source of accidents fills an important gap in the available carbon dioxide accident history and may provide a unique empirical perspective on the hazards of handling very large amounts...

  20. Ultrafast measurements of chlorine dioxide photochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Ludowise, P.D.

    1997-08-01

    Time-resolved mass spectrometry and time-resolved photoelectron spectroscopy are used to study the ultrafast photodissociation dynamics of chlorine dioxide, an important constituent in stratospheric ozone depletion. Chapter 1 introduces these pump/probe techniques, in which a femtosecond pump pulse excites a molecule to a dissociative state. At a later time, a second femtosecond probe pulse ionizes the molecule. The resulting mass and photoelectron spectra are acquired as a function of the delay between the pump and probe pulses, which follows the evolution of the molecule on the excited state. A comparison to other techniques used to study reaction dynamics is discussed. Chapter 2 includes a detailed description of the design and construction of the experimental apparatus, which consists of a femtosecond laser system, a molecular beam time-of-flight spectrometer, and a data acquisition system. The time-of-flight spectrometer is specifically designed to have a short flight distance to maximize the photoelectron collection efficiency without degrading the resolution, which is limited by the bandwidth of the femtosecond laser system. Typical performance of the apparatus is demonstrated in a study of the time-resolved photoelectron spectroscopy of nitric oxide. The results of the time-resolved mass spectrometry experiments of chlorine dioxide are presented in Chapter 3. Upon excitation to the A {sup 2}A{sub 2} state near 3.2 eV, the molecule dissociates through an indirect two-step mechanism. The direct dissociation channel has been predicted to be open, but is not observed. A quantum beat is observed in the OClO{sup +} species, which is described as a vibrational coherence of the optically prepared A {sup 2}A{sub 2} state. Chapter 4 presents the results of the time-resolved photoelectron experiments of chlorine dioxide. At short delay time, the quantum beat of the OClO{sup +} species is observed in the X {sup 1}A{sub 1} state of the ion. At infinite delay, the signal

  1. Carbon Dioxide: The Other Planetary Fluid

    Science.gov (United States)

    Glaser, S.; Gamez, D.; Shock, E.

    2016-12-01

    Cometary and interstellar ices have carbon dioxide to water mole ratios of up to 0.3. When melted, such high levels of carbon dioxide cannot all be dissolved in the aqueous phase and instead partition into a CO2-rich (carbonic) fluid. This implies that during the accretion and formation of planetary systems carbonic fluids are not only possible, but common. In fact, they make up the atmosphere of Venus, are found bubbling out of Champagne Vent in the Pacific Ocean, and are documented by metamorphic fluid inclusions. Examination of phase diagrams reveals the conditions where carbonic fluids will exist or predominate. Carbonic fluids are predicted to exist in Earth's subduction zones and under the ice of small ocean worlds. CO2 had previously been shown to completely dissolve into NH­­3­-H­­2O oceans on small icy bodies by forming ammonium carbonate, but the newer measurements of CO2­ abundances indicate that not all of the CO2 can partition into the aqueous fluid as ammonium carbonate. The remaining CO2 would necessarily form a separate carbonic fluid making it likely that liquid CO2 would be a major oceanic component on some small icy bodies. The enhanced solubility of nonpolar and slightly polar organic compounds in carbonic fluids relative to aqueous fluids means that generation, transport, and deposition processes can be greatly enhanced in those cases where carbonic fluids occur. As an example, the solubility of benzoic acid, a polar compound, is about an order of magnitude greater in carbonic than in aqueous fluids, which is surprising given that water is a polar solvent and carbon dioxide is a nonpolar solvent. Anthracene, a nonpolar compound, has an even greater solubility difference between carbonic and aqueous fluids at approximately four orders of magnitude. Highly polar compounds, including most of the building blocks of life, are more soluble in aqueous fluids than in carbonic fluids. The solubility difference of organic molecules in carbonic

  2. Photobiological hydrogen production and carbon dioxide sequestration

    Science.gov (United States)

    Berberoglu, Halil

    Photobiological hydrogen production is an alternative to thermochemical and electrolytic technologies with the advantage of carbon dioxide sequestration. However, it suffers from low solar to hydrogen energy conversion efficiency due to limited light transfer, mass transfer, and nutrient medium composition. The present study aims at addressing these limitations and can be divided in three parts: (1) experimental measurements of the radiation characteristics of hydrogen producing and carbon dioxide consuming microorganisms, (2) solar radiation transfer modeling and simulation in photobioreactors, and (3) parametric experiments of photobiological hydrogen production and carbon dioxide sequestration. First, solar radiation transfer in photobioreactors containing microorganisms and bubbles was modeled using the radiative transport equation (RTE) and solved using the modified method of characteristics. The study concluded that Beer-Lambert's law gives inaccurate results and anisotropic scattering must be accounted for to predict the local irradiance inside a photobioreactor. The need for accurate measurement of the complete set of radiation characteristics of microorganisms was established. Then, experimental setup and analysis methods for measuring the complete set of radiation characteristics of microorganisms have been developed and successfully validated experimentally. A database of the radiation characteristics of representative microorganisms have been created including the cyanobacteria Anabaena variabilis, the purple non-sulfur bacteria Rhodobacter sphaeroides and the green algae Chlamydomonas reinhardtii along with its three genetically engineered strains. This enabled, for the first time, quantitative assessment of the effect of genetic engineering on the radiation characteristics of microorganisms. In addition, a parametric experimental study has been performed to model the growth, CO2 consumption, and H 2 production of Anabaena variabilis as functions of

  3. Key Frame Extraction in the Summary Space.

    Science.gov (United States)

    Li, Xuelong; Zhao, Bin; Lu, Xiaoqiang

    2017-07-04

    Key frame extraction is an efficient way to create the video summary which helps users obtain a quick comprehension of the video content. Generally, the key frames should be representative of the video content, meanwhile, diverse to reduce the redundancy. Based on the assumption that the video data are near a subspace of a high-dimensional space, a new approach, named as key frame extraction in the summary space, is proposed for key frame extraction in this paper. The proposed approach aims to find the representative frames of the video and filter out similar frames from the representative frame set. First of all, the video data are mapped to a high-dimensional space, named as summary space. Then, a new representation is learned for each frame by analyzing the intrinsic structure of the summary space. Specifically, the learned representation can reflect the representativeness of the frame, and is utilized to select representative frames. Next, the perceptual hash algorithm is employed to measure the similarity of representative frames. As a result, the key frame set is obtained after filtering out similar frames from the representative frame set. Finally, the video summary is constructed by assigning the key frames in temporal order. Additionally, the ground truth, created by filtering out similar frames from human-created summaries, is utilized to evaluate the quality of the video summary. Compared with several traditional approaches, the experimental results on 80 videos from two datasets indicate the superior performance of our approach.

  4. Carbon dioxide and climate. [Appendix includes names and addresses of the Principal Investigators for the research projects funded in FY1991

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    Global climate change is a serious environmental concern, and the US has developed An Action Agenda'' to deal with it. At the heart of the US effort is the US Global Change Research Program (USGCRP), which has been developed by the Committee on Earth and Environmental Sciences (CEES) of the Federal Coordinating Council for Sciences, Engineering, and Technology (FCCSET). The USGCRP will provide the scientific basis for sound policy making on the climate-change issue. The DOE contribution to the USGCRP is the Carbon Dioxide Research Program, which now places particular emphasis on the rapid improvement of the capability to predict global and regional climate change. DOE's Carbon Dioxide Research Program has been addressing the carbon dioxide-climate change connection for more than twelve years and has provided a solid scientific foundation for the USGCRP. The expansion of the DOE effort reflects the increased attention that the Department has placed on the issue and is reflected in the National Energy Strategy (NES) that was released in 1991. This Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1991 and gives a brief overview of objectives, organization, and accomplishments. The Environmental Sciences Division of the Office of Health and Environmental Research, Office of Energy Research supports a Carbon Dioxide Research Program to determine the scientific linkage between the rise of greenhouse gases in the atmosphere, especially carbon dioxide, and climate and vegetation change. One facet is the Core CO{sub 2} Program, a pioneering program that DOE established more than 10 years ago to understand and predict the ways that fossil-fuel burning could affect atmospheric CO{sub 2} concentration, global climate, and the Earth's biosphere. Major research areas are: global carbon cycle; climate detection and models of climate change; vegetation research; resource analysis; and, information and integration.

  5. 78 FR 21340 - Information Collection: Annual Wildfire Summary Report

    Science.gov (United States)

    2013-04-10

    ... Forest Service Information Collection: Annual Wildfire Summary Report AGENCY: Forest Service, USDA... a currently approved information collection; Annual Wildfire Summary Report. DATES: Comments must be... of the year, including holidays. SUPPLEMENTARY INFORMATION: Title: Annual Wildfire Summary Report...

  6. Interaction of sulfur dioxide and carbon dioxide with clean silver in ultrahigh vacuum.

    Science.gov (United States)

    Lassiter, W. S.

    1972-01-01

    It is shown that when a clean polycrystalline silver surface is subjected to sulfur dioxide at a pressure of 1 nanotorr, sulfur is chemisorbed to the silver. Heating the contaminated silver leads to an estimation of the minimum heat of desorption of 59 kcal/mol. Sulfur Auger peak height and relative function measurements of the surface during exposure show that adsorption occurs during 6 microtorr/sec exposure at 1 nanotorr.

  7. Hydrodynamic Controls on Carbon Dioxide Efflux from Inland Waters

    Science.gov (United States)

    Long, H. E.; Waldron, S.; Hoey, T.; Newton, J.; Quemin, S.

    2013-12-01

    Intensive research has been undertaken on carbon dioxide efflux from lakes, estuaries and oceans, but much less attention has been given to rivers and streams, especially lower order streams. River systems are often over-saturated with carbon dioxide and so tend to act as sources of carbon dioxide to the atmosphere. It has been thought that rivers act as pipes carrying this terrestrial carbon to the oceans. However, recent studies have shown that a significant amount of the carbon is reprocessed within the system in a series of transformations and losses. Fluvial evasion of carbon dioxide is now recognised to be a significant component of carbon cycles, however the factors controlling carbon dioxide efflux and its magnitude remain poorly understood and quantified. This research aims to quantify, and better understand the controls on, freshwater carbon dioxide evasion. Data are presented here from field measurements that commenced in Sept 2013 in two contrasting Scottish rivers: the River Kelvin which has a large (335 km.sq) part-urban catchment with predominantly non-peat soils and Drumtee Water, a small (9.6 km.sq) rural catchment of peat soils and agricultural land. Using a floating chamber with the headspace connected to an infrared gas analyser to measure changes in carbon dioxide concentration, efflux rates from 0.22 - 47.4 μmol CO2/m.sq/sec were measured, these close to the middle of the range of previously reported values. At one site on the River Kelvin in May 2013 an influx of -0.61 - -3.53 μmol CO2/m.sq/sec was recorded. Whereas previous research finds carbon dioxide efflux to increase with decreasing river size and a more organic-rich soil catchment, here the controls on carbon dioxide evasion are similar across the contrasting catchments. Carbon dioxide evasion shows seasonality, with maximum fluxes in the summer months being up to twice as high as the winter maxima. Linear regression demonstrates that evasion increases with increased flow velocity

  8. Layered solid sorbents for carbon dioxide capture

    Science.gov (United States)

    Li, Bingyun; Jiang, Bingbing; Gray, McMahan L; Fauth, Daniel J; Pennline, Henry W; Richards, George A

    2013-02-25

    A solid sorbent for the capture and the transport of carbon dioxide gas is provided having at least one first layer of a positively charged material that is polyethylenimine or poly(allylamine hydrochloride), that captures at least a portion of the gas, and at least one second layer of a negatively charged material that is polystyrenesulfonate or poly(acryclic acid), that transports the gas, wherein the second layer of material is in juxtaposition to, attached to, or crosslinked with the first layer for forming at least one bilayer, and a solid substrate support having a porous surface, wherein one or more of the bilayers is/are deposited on the surface of and/or within the solid substrate. A method of preparing and using the solid sorbent is provided.

  9. Carbon Dioxide Capture Adsorbents: Chemistry and Methods.

    Science.gov (United States)

    Patel, Hasmukh A; Byun, Jeehye; Yavuz, Cafer T

    2017-04-10

    Excess carbon dioxide (CO 2 ) emissions and their inevitable consequences continue to stimulate hard debate and awareness in both academic and public spaces, despite the widespread lack of understanding on what really is needed to capture and store the unwanted CO 2 . Of the entire carbon capture and storage (CCS) operation, capture is the most costly process, consisting of nearly 70 % of the price tag. In this tutorial review, CO 2 capture science and technology based on adsorbents are described and evaluated in the context of chemistry and methods, after briefly introducing the current status of CO 2 emissions. An effective sorbent design is suggested, whereby six checkpoints are expected to be met: cost, capacity, selectivity, stability, recyclability, and fast kinetics. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Carbon dioxide: Global warning for nephrologists.

    Science.gov (United States)

    Marano, Marco; D'Amato, Anna; Cantone, Alessandra

    2016-09-06

    The large prevalence of respiratory acid-base disorders overlapping metabolic acidosis in hemodialysis population should prompt nephrologists to deal with the partial pressure of carbon dioxide (pCO2) complying with the reduced bicarbonate concentration. What the most suitable formula to compute pCO2 is reviewed. Then, the neglected issue of CO2 content in the dialysis fluid is under the spotlight. In fact, a considerable amount of CO2 comes to patients' bloodstream every hemodialysis treatment and "acidosis by dialysate" may occur if lungs do not properly clear away this burden of CO2. Moreover, vascular access recirculation may be easy diagnosed by detecting CO2 in the arterial line of extracorporeal circuit if CO2-enriched blood from the filter reenters arterial needle.

  11. Algae: putting carbon dioxide in a bind

    Energy Technology Data Exchange (ETDEWEB)

    Ewers, J.; Wiechers, G. [RWE Power (Germany)

    2009-03-15

    German utility RWE Power has initiated a cutting edge project that is investigating the use of marine microalgae to capture carbon dioxide produced during lignite combustion. At its Niederaussem power plant, a pilot plant has been erected for the production of microalgae. Flue gas is withdrawn from the lignite-based power plant and transported through polyethylene pipes to the microalgae production plant. The CO{sub 2} in the flue gas is dissolved in the algae suspension and adsorbed by the algae for growth in photobioreactors, developed by Noragreen Projektmanagement GmbH. The photobioreactors which consist of clear plastic hoses, fixed in V shape to supports. The study is aiming to optimise the entire algae production process and subsequent conversion and use of the algae biomass produced. Uses being investigated include hydrothermal carbonization to obtain hydrocarbon products. 1 figs., 1 photo.

  12. Dispersion Polymerizations in Supercritical Carbon Dioxide

    Science.gov (United States)

    Desimone, J. M.; Maury, E. E.; Menceloglu, Y. Z.; McClain, J. B.; Romack, T. J.; Combes, J. R.

    1994-07-01

    Conventional heterogeneous dispersion polymerizations of unsaturated monomers are performed in either aqueous or organic dispersing media with the addition of interfacially active agents to stabilize the colloidal dispersion that forms. Successful stabilization of the polymer colloid during polymerization results in the formation of high molar mass polymers with high rates of polymerization. An environmentally responsible alternative to aqueous and organic dispersing media for heterogeneous dispersion polymerizations is described in which supercritical carbon dioxide (CO_2) is used in conjunction with molecularly engineered free radical initiators and amphipathic molecules that are specifically designed to be interfacially active in CO_2. Conventional lipophilic monomers, exemplified by methyl methacrylate, can be quantitatively (>90 percent) polymerized heterogeneously to very high degrees of polymerization (>3000) in supercritical CO_2 in the presence of an added stabilizer to form kinetically stable dispersions that result in micrometer-sized particles with a narrow size distribution.

  13. Carbon dioxide emissions from biochar in soil

    DEFF Research Database (Denmark)

    Bruun, Sander; Clauson-Kaas, Anne Sofie Kjærulff; Bobuľská, L.

    2014-01-01

    The stability of biochar in soil is of importance if it is to be used for carbon sequestration and long-term improvement of soil properties. It is well known that a significant fraction of biochar is highly stable in soil, but carbon dioxide (CO2) is also released immediately after application....... This study investigated the nature of the early release of CO2 and the degree to which stabilizing mechanisms protect biochar from microbial attack. Incubations of 14C-labelled biochar produced at different temperatures were performed in soils with different clay contents and in sterilized and non......-sterilized soils. It emerged that carbonate may be concentrated or form during or after biochar production, resulting in significant carbonate contents. If CO2 released from carbonates in short-term experiments is misinterpreted as mineralization of biochar, the impact of this process may be significantly over...

  14. Carbon Dioxide in Arable Soil Profiles

    DEFF Research Database (Denmark)

    Chirinda, Ngoni; Plauborg, Finn; Heckrath, Goswin Johann

    2014-01-01

    ; however, differences may occur in response to soil spatial variability. A better coverage of spatial variability is more easily addressed using manually operated systems whereas temporal variability can be covered using the automated system. Depending on the aim of the study, the two systems may be used......Carbon dioxide (CO2) concentrations in arable soil profiles are influenced by autotrophic and heterotrophic respiration as well as soil physical properties that regulate gas transport. Whereas different methods have been used to assess dynamics of soil CO2 concentrations, our understanding...... on the comparability of results obtained using different methods is limited. We therefore aimed to compare the dynamics in soil CO2 concentrations obtained from an automated system (GMP343 sensors) to those from a manually operated measurement system (i.e., soil gas sampled using stainless steel needles and rods...

  15. Preparation and integration of nanostructured titanium dioxide

    KAUST Repository

    Zeng, Hua Chun

    2011-10-01

    Titanium dioxide (TiO2) is a chemically stable nontoxic transition-metal oxide associated with a wide range of existing chemical engineering processes. In this short review, recent research endeavors in preparation and integration of nanostructured TiO2 materials system will be featured and discussed for their potential new applications. Because material development always plays pivotal roles in the progress of a particular engineering discipline, the reviewed subjects will provide useful information to stimulate nanoscale research of chemical engineering, linking established fundamentals with practical applications. Some critical issues and challenges regarding further development of this important functional material for nanotechnology will also be addressed. © 2011 Elsevier Ltd. All rights reserved.

  16. Medical device disinfection by dense carbon dioxide.

    Science.gov (United States)

    Bertoloni, G; Bertucco, A; Rassu, M; Vezzù, K

    2011-01-01

    The employment of disinfection-sterilisation processes for the re-use of medical devices without negative effects such as the presence of toxic residues, material degradation or other modifications is an important consideration for reducing the costs of surgical and medical procedures. Ethylene oxide is the most commonly used low temperature sterilisation technique in healthcare facilities, but its associated toxicity has reduced interest in this technology for the reprocessing of medical equipment. The aim of this study was to examine the disinfection efficiency of a novel low temperature approach, based on dense carbon dioxide on artificially contaminated catheters. The results obtained demonstrated that this method provided a complete inactivation of all bacteria and yeast strains tested, and that no obvious modifications to the surfaces tested were observed with multiple treatments. Copyright © 2010 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved.

  17. Pulsed-discharge carbon dioxide lasers

    Science.gov (United States)

    Willetts, David V.

    1990-01-01

    The purpose is to attempt a general introduction to pulsed carbon dioxide lasers of the kind used or proposed for laser radar applications. Laser physics is an excellent example of a cross-disciplinary topic, and the molecular spectroscopy, energy transfer, and plasma kinetics of the devices are explored. The concept of stimulated emission and population inversions is introduced, leading on to the molecular spectroscopy of the CO2 molecule. This is followed by a consideration of electron-impact pumping, and the pertinent energy transfer and relaxation processes which go on. Since the devices are plasma pumped, it is necessary to introduce a complex subject, but this is restricted to appropriate physics of glow discharges. Examples of representative devices are shown. The implications of the foregoing to plasma chemistry and gas life are discussed.

  18. Alberta ambient air quality objectives : sulphur dioxide

    International Nuclear Information System (INIS)

    2011-02-01

    Sulphur dioxide (SO 2 ) is a colourless, non-flammable gas with a pungent odour. Exposure to SO 2 can result in numerous effects to the pulmonary system. This paper outlined current Alberta ambient air quality objectives in relation to SO 2 . The 1-hour average Alberta ambient air quality objective for SO 2 is currently 450 μg per m 3 . Studies conducted with healthy humans showed increased airway resistance and bronchoconstriction, as well as decreased maximum expiratory flow. Exercise can increase the severity of response to SO 2 in healthy and asthmatic individuals. Long-term exposure to SO 2 levels can also impact the metabolic activity of vegetation. The United States Environmental Protection Agency (EPA) recently announced their intention to reduce the 1-hour SO 2 standard to between 131 to 262 μg per m 3 . 7 refs.

  19. Fluorination reaction uranium dioxide by fluorine

    International Nuclear Information System (INIS)

    Ogata, Shinji; Homma, Shunji; Koga, Jiro; Matsumoto, Shiro; Sasahira, Akira; Kawamura, Fumio

    2004-01-01

    Kinetics of the fluorination reaction of uranium dioxide is studied using un-reacted core model with shrinking particles. The model includes the film mass transfer of fluorine gas and its diffusion in the particle. The rate constants of the model are determined by fitting the experimental data for 370-450degC. The model successfully represents the fluorination in this temperature range. The rate control step is identified by examining the rate constants of the model for 300-1,800degC. For temperature range up to 900degC, the fluorination reaction is rate controlling. For over 900degC, both mechanisms of the mass transfer of fluorine and the fluorination reaction control the rate of the fluorination. With further increase of the temperature, however, the fluorination reaction becomes so fast that the mass transfer of fluorine eventually controls the rate of the fluorination. (author)

  20. Growth and characterization of iridium dioxide nanorods

    International Nuclear Information System (INIS)

    Chen, R.S.; Huang, Y.S.; Liang, Y.M.; Tsai, D.S.; Tiong, K.K.

    2004-01-01

    Conductive iridium dioxide (IrO 2 ) nanorods have been successfully grown on the Si(1 0 0) substrates via metalorganic chemical vapor deposition (MOCVD). A wedge-shaped morphology and naturally formed sharp tips are observed for IrO 2 nanorods using field-emission scanning electron microscopy (FESEM). High-resolution transmission electron microscopy (TEM) image and electron diffraction pattern show the growth of IrO 2 nanorods preferentially along c-axis. Structure and composition of IrO 2 nanorods have also been characterized using the techniques of Raman spectroscopy and X-ray photoelectron spectroscopy (XPS), respectively. It is noted that the IrO 2 nanorods are self-mediated instead of the conventional vapor-liquid-solid (VLS) approach or catalyst-mediated method