WorldWideScience

Sample records for volatility process recovers

  1. A POLYMER-CERAMIC COMPOSITE MEMBRANE FOR RECOVERING VOLATILE ORGANIC COMPOUNDS FROM WASTEWATERS BY PERVAPORATION

    Science.gov (United States)

    A composite membrane was constructed on a porous ceramic support from a block copolymer of styrene and butadiene (SBS). It was tested in a laboratory pervaporation apparatus for recovering volatile organic compounds (VOCs) such a 1,1,1-trichloroethane (TCA) and trichloroethylene ...

  2. Nitrogen Trifluoride-Based Fluoride- Volatility Separations Process: Initial Studies

    Energy Technology Data Exchange (ETDEWEB)

    McNamara, Bruce K.; Scheele, Randall D.; Casella, Andrew M.; Kozelisky, Anne E.

    2011-09-28

    This document describes the results of our investigations on the potential use of nitrogen trifluoride as the fluorinating and oxidizing agent in fluoride volatility-based used nuclear fuel reprocessing. The conceptual process uses differences in reaction temperatures between nitrogen trifluoride and fuel constituents that produce volatile fluorides to achieve separations and recover valuable constituents. We provide results from our thermodynamic evaluations, thermo-analytical experiments, kinetic models, and provide a preliminary process flowsheet. The evaluations found that nitrogen trifluoride can effectively produce volatile fluorides at different temperatures dependent on the fuel constituent.

  3. HS-GC-MS Volatile compounds recovered in freshly pressed and commercial Wonderful pomegranate juices

    Science.gov (United States)

    Consumption and production of superfruits has been increasing. Highly colored fruits often have bitter and astringent components that may make them undesirable, especially when processed. Many pomegranate volatile reports involved commercial samples, complicated isolation methods, or blending and ...

  4. Volatility Determination in an Ambit Process Setting

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole; Graversen, Svend-Erik

    The probability limit behaviour of normalised quadratic variation is studied for a simple tempo-spatial ambit process, with particular regard to the question of volatility memorylessness.......The probability limit behaviour of normalised quadratic variation is studied for a simple tempo-spatial ambit process, with particular regard to the question of volatility memorylessness....

  5. On multi-scaling in volatility processes

    NARCIS (Netherlands)

    Capobianco, E.

    2002-01-01

    Among the statistical features of financial volatility processes, the most challenging for statistical inference purposes are non-gaussianity and non-stationarity. In this study I present results from experiments aimed to empirically modeling return generating processes in which the underlying volat

  6. Innovative Elution Processes for Recovering Uranium from Seawater

    Energy Technology Data Exchange (ETDEWEB)

    Wai, Chien [Univ. of Idaho, Moscow, ID (United States); Tian, Guoxin [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Janke, Christopher [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-05-29

    Utilizing amidoxime-based polymer sorbents for extraction of uranium from seawater has attracted considerable interest in recent years. Uranium collected in the sorbent is recovered typically by elution with an acid. One drawback of acid elution is deterioration of the sorbent which is a significant factor that limits the economic competitiveness of the amidoxime-based sorbent systems for sequestering uranium from seawater. Developing innovative elution processes to improve efficiency and to minimize loss of sorbent capacity become essential in order to make this technology economically feasible for large-scale industrial applications. This project has evaluated several elution processes including acid elution, carbonate elution, and supercritical fluid elution for recovering uranium from amidoxime-based polymer sorbents. The elution efficiency, durability and sorbent regeneration for repeated uranium adsorption- desorption cycles in simulated seawater have been studied. Spectroscopic techniques are used to evaluate chemical nature of the sorbent before and after elution. A sodium carbonate-hydrogen peroxide elution process for effective removal of uranium from amidoxime-based sorbent is developed. The cause of this sodium carbonate and hydrogen peroxide synergistic leaching of uranium from amidoxime-based sorbent is attributed to the formation of an extremely stable uranyl peroxo-carbonato complex. The efficiency of uranium elution by the carbonate-hydrogen peroxide method is comparable to that of the hydrochloric acid elution but damage to the sorbent material is much less for the former. The carbonate- hydrogen peroxide elution also does not need any elaborate step to regenerate the sorbent as those required for hydrochloric acid leaching. Several CO2-soluble ligands have been tested for extraction of uranium from the sorbent in supercritical fluid carbon dioxide. A mixture of hexafluoroacetylacetone and tri-n-butylphosphate shows the best result but uranium

  7. Different strategies for recovering metals from CARON process residue

    Energy Technology Data Exchange (ETDEWEB)

    Cabrera, G., E-mail: gema.cabrera@uca.es [Biological and Enzymatic Reactors Group, Department of Chemical Engineering and Food Technology, Faculty of Sciences, University of Cadiz (Spain); Gomez, J.M., E-mail: josemanuel.montesdeoca@uca.es [Biological and Enzymatic Reactors Group, Department of Chemical Engineering and Food Technology, Faculty of Sciences, University of Cadiz (Spain); Hernandez, I., E-mail: ianeyahd@fbio.uh.cu [Laboratory of Metals, Department of Microbiology, Faculty of Biology, University of Havana (Cuba); Coto, O., E-mail: ocoto@fbio.uh.cu [Laboratory of Metals, Department of Microbiology, Faculty of Biology, University of Havana (Cuba); Cantero, D., E-mail: domingo.cantero@uca.es [Biological and Enzymatic Reactors Group, Department of Chemical Engineering and Food Technology, Faculty of Sciences, University of Cadiz (Spain)

    2011-05-30

    The capacity of Acidithiobacillus thiooxidans DMS 11478 to recover the heavy metals contained in the residue obtained from the CARON process has been evaluated. Different bioreactor configurations were studied: a two-stage batch system and two semi-continuous systems (stirred-tank reactor leaching and column leaching). In the two-stage system, 46.8% Co, 36.0% Mg, 26.3% Mn and 22.3% Ni were solubilised after 6 h of contact between the residue and the bacteria-free bioacid. The results obtained with the stirred-tank reactor and the column were similar: 50% of the Mg and Co and 40% of the Mn and Ni were solubilised after thirty one days. The operation in the column reactor allowed the solid-liquid ratio to be increased and the pH to be kept at low values (<1.0). Recirculation of the leachate in the column had a positive effect on metal removal; at sixty five days (optimum time) the solubilisation levels were as follows: 86% Co, 83% Mg, 72% Mn and Ni, 62% Fe and 23% Cr. The results corroborate the feasibility of the systems studied for the leaching of metals from CARON process residue and these methodologies can be considered viable for the recovery of valuable metals.

  8. Modeling Multivariate Volatility Processes: Theory and Evidence

    Directory of Open Access Journals (Sweden)

    Jelena Z. Minovic

    2009-05-01

    Full Text Available This article presents theoretical and empirical methodology for estimation and modeling of multivariate volatility processes. It surveys the model specifications and the estimation methods. Multivariate GARCH models covered are VEC (initially due to Bollerslev, Engle and Wooldridge, 1988, diagonal VEC (DVEC, BEKK (named after Baba, Engle, Kraft and Kroner, 1995, Constant Conditional Correlation Model (CCC, Bollerslev, 1990, Dynamic Conditional Correlation Model (DCC models of Tse and Tsui, 2002, and Engle, 2002. I illustrate approach by applying it to daily data from the Belgrade stock exchange, I examine two pairs of daily log returns for stocks and index, report the results obtained, and compare them with the restricted version of BEKK, DVEC and CCC representations. The methods for estimation parameters used are maximum log-likehood (in BEKK and DVEC models and twostep approach (in CCC model.

  9. Altered Reward Processing in Women Recovered From Anorexia Nervosa

    National Research Council Canada - National Science Library

    Venkatraman, Vijay K; Fischer, Lorie; Bailer, Ursula F; Aizenstein, Howard; May, J. Christopher; Frank, Guido K; Carter, Cameron; Putnam, Karen; Fudge, Julie; Kaye, Walter H; Wagner, Angela; Mazurkewicz, Laura; Nguyen, Van

    2007-01-01

    .... To avoid the confounding effects of malnutrition, the authors compared 13 healthy comparison women and 13 women who had recovered from restricting-type anorexia nervosa and had 1 year of normal...

  10. Profiles of impaired, spared, and recovered neuropsychologic processes in alcoholism.

    Science.gov (United States)

    Oscar-Berman, Marlene; Valmas, Mary M; Sawyer, Kayle S; Ruiz, Susan Mosher; Luhar, Riya B; Gravitz, Zoe R

    2014-01-01

    Long-term chronic alcoholism is associated with disparate and widespread residual consequences for brain functioning and behavior, and alcoholics suffer a variety of cognitive deficiencies and emotional abnormalities. Alcoholism has heterogeneous origins and outcomes, depending upon factors such as family history, age, gender, and mental or physical health. Consequently, the neuropsychologic profiles associated with alcoholism are not uniform among individuals. Moreover, within and across research studies, variability among subjects is substantial and contributes to characteristics associated with differential treatment outcomes after detoxification. In order to refine our understanding of alcoholism-related impaired, spared, and recovered abilities, we focus on five specific functional domains: (1) memory; (2) executive functions; (3) emotion and psychosocial skills; (4) visuospatial cognition; and (5) psychomotor abilities. Although the entire brain might be vulnerable in uncomplicated alcoholism, the brain systems that are considered to be most at risk are the frontocerebellar and mesocorticolimbic circuitries. Over time, with abstinence from alcohol, the brain appears to become reorganized to provide compensation for structural and behavioral deficits. By relying on a combination of clinical and scientific approaches, future research will help to refine the compensatory roles of healthy brain systems, the degree to which abstinence and treatment facilitate the reversal of brain atrophy and dysfunction, and the importance of individual differences to outcome. © 2014 Elsevier B.V. All rights reserved.

  11. Development of volatile compounds in processed cheese during storage

    DEFF Research Database (Denmark)

    Sunesen, Lars Oddershede; Lund, Pia; Sørensen, J.

    2002-01-01

    The purpose of this work teas to study tire impact of storage conditions, such as light and temperature, on the development of volatile compounds to processed cheese. Cheese in glass containers was stored at 5, 20 or 37 degreesC in light or darkness for up to 1 yr. Dynamic headspace and gas...

  12. Recovering a stochastic process from super-resolution noisy ensembles of single-particle trajectories.

    Science.gov (United States)

    Hoze, N; Holcman, D

    2015-11-01

    Recovering a stochastic process from noisy ensembles of single-particle trajectories is resolved here using the coarse-grained Langevin equation as a model. The massive redundancy contained in single-particle tracking data allows recovering local parameters of the underlying physical model. We use several parametric and nonparametric estimators to compute the first and second moments of the process, to recover the local drift, its derivative, and the diffusion tensor, and to deconvolve the instrumental from the physical noise. We use numerical simulations to also explore the range of validity for these estimators. The present analysis allows defining what can exactly be recovered from statistics of super-resolution microscopy trajectories used for characterizing molecular trafficking underlying cellular functions.

  13. Active non-volatile memory post-processing

    Energy Technology Data Exchange (ETDEWEB)

    Kannan, Sudarsun; Milojicic, Dejan S.; Talwar, Vanish

    2017-04-11

    A computing node includes an active Non-Volatile Random Access Memory (NVRAM) component which includes memory and a sub-processor component. The memory is to store data chunks received from a processor core, the data chunks comprising metadata indicating a type of post-processing to be performed on data within the data chunks. The sub-processor component is to perform post-processing of said data chunks based on said metadata.

  14. Active non-volatile memory post-processing

    Science.gov (United States)

    Kannan, Sudarsun; Milojicic, Dejan S.; Talwar, Vanish

    2017-04-11

    A computing node includes an active Non-Volatile Random Access Memory (NVRAM) component which includes memory and a sub-processor component. The memory is to store data chunks received from a processor core, the data chunks comprising metadata indicating a type of post-processing to be performed on data within the data chunks. The sub-processor component is to perform post-processing of said data chunks based on said metadata.

  15. Volatile components of the frying process

    Directory of Open Access Journals (Sweden)

    Nawar, W. W.

    1998-08-01

    Full Text Available In the course of deep fat frying, food contacts oil at about 180 °C and is partially exposed to air for various periods of time. Thus frying, more than any other standard food process or handling method, has the greatest potential for causing chemical changes in fat, and sizeable amounts of this fat are carried with the food (5-40% fat by weight is absorbed. During frying, oxidative reactions involving the formation and decomposition of hydroperoxides lead to such compounds as saturated and unsaturated aldehydes, ketones, hydrocarbons, lactones, alcohols, acids and esters. Sulfur compounds and pyrazine derivatives may develop in the food itself or from the interactions between the food and oil. Food absorbs varying amounts of oil during deep-fat frying (potato chips have a final fat content of about 35%. The food itself can release some of its endogenous lipids (e.g., fat from chicken into the frying fat and consequently the oxidative stability of the new mixture may be different from that of the original frying fat. The changes that occur in the oil and food during frying should not be automatically construed as undesirable or harmful. In fact, some of these changes are necessary to provide the sensory qualities typical of fried food. On the other hand, extensive decomposition, resulting from lack of adequate control of the frying operation, can be a potential source of damage not only to sensory quality of the fried food but also to nutritional value.

  16. Option Pricing with Stochastic Volatility and Jump Diffusion Processes

    Directory of Open Access Journals (Sweden)

    Radu Lupu

    2006-05-01

    Full Text Available Option pricing by the use of Black Scholes Merton (BSM model is based on the assumption that asset prices have a lognormal distribution. In spite of the use of these models on a large scale, both by practioners and academics, the assumption of lognormality is rejected by the history of returns. The objective of this article is to present the methods that developed after the Black Scholes Merton environment and deals with the option pricing model adjustment to the empirical properties of asset returns. The main models that appeared after BSM allowed for special changes of the returns that materialized in jump-diffusion and stochastic volatility processes. The article presents the foundations of risk neutral options evaluation and the empirical evidence that fed the amendment of the lognormal assumption in the first part and shows the evaluation procedure under the assumption of stock prices following the jump-diffusion process and the stochastic volatility process.

  17. Option Pricing with Stochastic Volatility and Jump Diffusion Processes

    Directory of Open Access Journals (Sweden)

    Radu Lupu

    2006-03-01

    Full Text Available Option pricing by the use of Black Scholes Merton (BSM model is based on the assumption that asset prices have a lognormal distribution. In spite of the use of these models on a large scale, both by practioners and academics, the assumption of lognormality is rejected by the history of returns. The objective of this article is to present the methods that developed after the Black Scholes Merton environment and deals with the option pricing model adjustment to the empirical properties of asset returns. The main models that appeared after BSM allowed for special changes of the returns that materialized in jump-diffusion and stochastic volatility processes. The article presents the foundations of risk neutral options evaluation and the empirical evidence that fed the amendment of the lognormal assumption in the first part and shows the evaluation procedure under the assumption of stock prices following the jump-diffusion process and the stochastic volatility process.

  18. Digi-Clima Grid: image processing and distributed computing for recovering historical climate data

    Directory of Open Access Journals (Sweden)

    Sergio Nesmachnow

    2015-12-01

    Full Text Available This article describes the Digi-Clima Grid project, whose main goals are to design and implement semi-automatic techniques for digitalizing and recovering historical climate records applying parallel computing techniques over distributed computing infrastructures. The specific tool developed for image processing is described, and the implementation over grid and cloud infrastructures is reported. A experimental analysis over institutional and volunteer-based grid/cloud distributed systems demonstrate that the proposed approach is an efficient tool for recovering historical climate data. The parallel implementations allow to distribute the processing load, achieving accurate speedup values.

  19. Integration of biohydrogen fermentation and gas separation processes to recover and enrich hydrogen

    NARCIS (Netherlands)

    Bélafi-Bakó, K.; Búcsú, D.; Pientka, Z.; Bálint, B.; Herbel, Z.; Kovács, K.I.; Wessling, Matthias

    2006-01-01

    An integrated system for biohydrogen production and separation was designed, constructed and operated where biohydrogen was fermented by Thermococcus litoralis, a heterotrophic archaebacterium, and a two-step gas separation process was coupled to recover and concentrate hydrogen. A special liquid

  20. Integration of biohydrogen fermentation and gas separation processes to recover and enrich hydrogen

    NARCIS (Netherlands)

    Bélafi-Bakó, K.; Búcsú, D.; Pientka, Z.; Bálint, B.; Herbel, Z.; Kovács, K.I.; Wessling, M.

    2006-01-01

    An integrated system for biohydrogen production and separation was designed, constructed and operated where biohydrogen was fermented by Thermococcus litoralis, a heterotrophic archaebacterium, and a two-step gas separation process was coupled to recover and concentrate hydrogen. A special liquid se

  1. Novel process to recover by-products from the pickling baths of stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Frias, C.; Negro, C.; Formoso, A.; Van Erkel, J.; Maas, W.; Kemppainen, J.; Mancia, F. [Tecnicas Reunidas, S.A., Madrid (Spain)

    2001-07-01

    Development of an integrated process (the PIBARE process) which is able to recover and recycle free and complex acids back to the pickling tank is described. The recovery of these by-products proceeds while the metals are recovered in the form of electrodeposited metal alloy and are internally recycled to the stainless steel manufacturing process. Virtually no solid residue or liquid is produced in the process. Results after three years of investigation are very promising, having achieved all stated objectives at least on the laboratory scale. The new technology promises significant economic and environmental benefits over other existing technologies for the treatment of spent baths. However, since the benefits have not been confirmed at the pilot scale, commercial application would require additional research, including finding more efficient and more selective anionic membranes. 3 tabs., 6 figs.

  2. Elevated cognitive control over reward processing in recovered female patients with anorexia nervosa.

    Science.gov (United States)

    Ehrlich, Stefan; Geisler, Daniel; Ritschel, Franziska; King, Joseph A; Seidel, Maria; Boehm, Ilka; Breier, Marion; Clas, Sabine; Weiss, Jessika; Marxen, Michael; Smolka, Michael N; Roessner, Veit; Kroemer, Nils B

    2015-09-01

    Individuals with anorexia nervosa are thought to exert excessive self-control to inhibit primary drives. This study used functional MRI (fMRI) to interrogate interactions between the neural correlates of cognitive control and motivational processes in the brain reward system during the anticipation of monetary reward and reward-related feedback. In order to avoid confounding effects of undernutrition, we studied female participants recovered from anorexia nervosa and closely matched healthy female controls. The fMRI analysis (including node-to-node functional connectivity) followed a region of interest approach based on models of the brain reward system and cognitive control regions implicated in anorexia nervosa: the ventral striatum, medial orbitofrontal cortex (mOFC) and dorsolateral prefrontal cortex (DLPFC). We included 30 recovered patients and 30 controls in our study. There were no behavioural differences and no differences in hemodynamic responses of the ventral striatum and the mOFC in the 2 phases of the task. However, relative to controls, recovered patients showed elevated DLPFC activity during the anticipation phase, failed to deactivate this region during the feedback phase and displayed greater functional coupling between the DLPFC and mOFC. Recovered patients also had stronger associations than controls between anticipation-related DLPFC responses and instrumental responding. The results we obtained using monetary stimuli might not generalize to other forms of reward. Unaltered neural responses in ventral limbic reward networks but increased recruitment of and connectivity with lateral-frontal brain circuitry in recovered patients suggests an elevated degree of selfregulatory processes in response to rewarding stimuli. An imbalance between brain systems subserving bottom-up and top-down processes may be a trait marker of the disorder.

  3. Green process to recover magnesium chloride from residue solution of potassium chloride production plant

    Institute of Scientific and Technical Information of China (English)

    Lin WANG; Yunliang HE; Yanfei WANG; Ying BAO; Jingkang WANG

    2008-01-01

    The green process to recover magnesium chlor-ide from the residue solution of a potassium chloride pro-duction plant, which comes from the leach solution of a potash mine in Laos, is designed and optimized. The res-idue solution contains magnesium chloride above 25 wt-%, potassium chloride and sodium chloride together below 5 wt-% and a few other ions such as Br-, SO2-4and Ca2+. The recovery process contains two steps: the previous impurity removal operation and the two-stage evapora-tion-cooling crystallization procedure to produce magnes-ium chloride. The crystallized impurity carnallite obtained from the first step is recycled to the potassium chloride plant to recover the potassium salt. The developed process is a zero discharge one and thus fulfills the requirements for green chemical industrial production. The produced magnesium chloride is up to industrial criteria.

  4. Mass, energy and material balances of SRF production process. Part 3: solid recovered fuel produced from municipal solid waste.

    Science.gov (United States)

    Nasrullah, Muhammad; Vainikka, Pasi; Hannula, Janne; Hurme, Markku; Kärki, Janne

    2015-02-01

    This is the third and final part of the three-part article written to describe the mass, energy and material balances of the solid recovered fuel production process produced from various types of waste streams through mechanical treatment. This article focused the production of solid recovered fuel from municipal solid waste. The stream of municipal solid waste used here as an input waste material to produce solid recovered fuel is energy waste collected from households of municipality. This article presents the mass, energy and material balances of the solid recovered fuel production process. These balances are based on the proximate as well as the ultimate analysis and the composition determination of various streams of material produced in a solid recovered fuel production plant. All the process streams are sampled and treated according to CEN standard methods for solid recovered fuel. The results of the mass balance of the solid recovered fuel production process showed that 72% of the input waste material was recovered in the form of solid recovered fuel; 2.6% as ferrous metal, 0.4% as non-ferrous metal, 11% was sorted as rejects material, 12% as fine faction and 2% as heavy fraction. The energy balance of the solid recovered fuel production process showed that 86% of the total input energy content of input waste material was recovered in the form of solid recovered fuel. The remaining percentage (14%) of the input energy was split into the streams of reject material, fine fraction and heavy fraction. The material balances of this process showed that mass fraction of paper and cardboard, plastic (soft) and wood recovered in the solid recovered fuel stream was 88%, 85% and 90%, respectively, of their input mass. A high mass fraction of rubber material, plastic (PVC-plastic) and inert (stone/rock and glass particles) was found in the reject material stream. © The Author(s) 2014.

  5. Testing for a Common Volatility Process and Information Spillovers in Bivariate Financial Time Series Models

    NARCIS (Netherlands)

    J. Chen (Jinghui); M. Kobayashi (Masahito); M.J. McAleer (Michael)

    2016-01-01

    textabstractThe paper considers the problem as to whether financial returns have a common volatility process in the framework of stochastic volatility models that were suggested by Harvey et al. (1994). We propose a stochastic volatility version of the ARCH test proposed by Engle and Susmel (1993),

  6. System of extraction of volatiles from soil using microwave processes

    Science.gov (United States)

    Ethridge, Edwin C. (Inventor); Kaukler, William F. (Inventor)

    2013-01-01

    A device for the extraction and collection of volatiles from soil or planetary regolith. The device utilizes core drilled holes to gain access to underlying volatiles below the surface. Microwave energy beamed into the holes penetrates through the soil or regolith to heat it, and thereby produces vapor by sublimation. The device confines and transports volatiles to a cold trap for collection.

  7. Solid recovered fuel production from biodegradable waste in grain processing industry.

    Science.gov (United States)

    Kliopova, Irina; Staniskis, Jurgis Kazimieras; Petraskiene, Violeta

    2013-04-01

    Management of biodegradable waste is one of the most important environmental problems in the grain-processing industry since this waste cannot be dumped anymore due to legal requirements. Biodegradable waste is generated in each stage of grain processing, including the waste-water and air emissions treatment processes. Their management causes some environmental and financial problems. The majority of Lithuanian grain-processing enterprises own and operate composting sites, but in Lithuania the demand for compost is not given. This study focused on the analysis of the possibility of using biodegradable waste for the production of solid recovered fuel, as a local renewable fuel with the purpose of increasing environmental performance and decreasing the direct costs of grain processing. Experimental research with regard to a pilot grain-processing plant has proven that alternative fuel production will lead to minimizing of the volume of biodegradable waste by 75% and the volume of natural gas for heat energy production by 62%. Environmental indicators of grain processing, laboratory analysis of the chemical and physical characteristics of biodegradable waste, mass and energy balances of the solid recovered fuel production, environmental and economical benefits of the project are presented and discussed herein.

  8. Family role in the reintegration process of recovering drug addicts: a qualitative review of Israeli offenders.

    Science.gov (United States)

    Gideon, Lior

    2007-04-01

    In an outcome evaluation of recovering addicts who participated in a prison-based therapeutic community, 39 clients, a nonrandomized subsample, are interviewed about their rehabilitation and reintegration experience. This study focuses on the family as the main source of support and as an agent of change for the recovering drug addict. Although many studies show marriage and family to be positively related to successful reintegration and rehabilitation, clients in this study report families as having a negative effect on the rehabilitation and reintegration process. This is especially true among those who reunite with their spouse. The findings are discussed in regard to role expectations and support mechanisms, and suggestions are made for further research.

  9. An application of stereoscopy and image processing in forensics: recovering obliterated firearms serial number

    Science.gov (United States)

    da Silva Nunes, L. C.; dos Santos, Paulo Acioly M.

    2004-10-01

    We present an application of the use of stereoscope to recovering obliterated firearms serial number. We investigate a promising new combined cheap method using both non-destructive and destructive techniques. With the use of a stereomicroscope coupled with a digital camera and a flexible cold light source, we can capture the image of the damaged area, and with continuous polishing and sometimes with the help of image processing techniques we could enhance the observed images and they can also be recorded as evidence. This method has already proven to be useful, in certain cases, in aluminum dotted pistol frames, whose serial number is printed with a laser, when etching techniques are not successful. We can also observe acid treated steel surfaces and enhance the images of recovered serial numbers, which sometimes lack of definition.

  10. Process for recovering alkali metals and sulfur from alkali metal sulfides and polysulfides

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, John Howard; Alvare, Javier

    2016-10-25

    Alkali metals and sulfur may be recovered from alkali monosulfide and polysulfides in an electrolytic process that utilizes an electrolytic cell having an alkali ion conductive membrane. An anolyte solution includes an alkali monosulfide, an alkali polysulfide, or a mixture thereof and a solvent that dissolves elemental sulfur. A catholyte includes molten alkali metal. Applying an electric current oxidizes sulfide and polysulfide in the anolyte compartment, causes alkali metal ions to pass through the alkali ion conductive membrane to the catholyte compartment, and reduces the alkali metal ions in the catholyte compartment. Liquid sulfur separates from the anolyte solution and may be recovered. The electrolytic cell is operated at a temperature where the formed alkali metal and sulfur are molten.

  11. Integration of biohydrogen fermentation and gas separation processes to recover and enrich hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Belafi-Bako, K.; Bucsu, D. [Research Institute of Chemical and Process Engineering, University of Veszprem, Egyetem u. 2., 8200 Veszprem (Hungary); Pientka, Z. [Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsky sq. 2., Prague (Czech Republic); Balint, B.; Herbel, Z.; Kovacs, K.L. [Department of Biotechnology and Institute of Biophysics, Biological Research Center, Hungarian Academy of Sciences, University of Szeged, Temesvari krt. 62., 6726 Szeged (Hungary); Wessling, M. [Membrane Technology Group, University of Twente, P.O. Box 217, 7500 AE Enschede (Netherlands)

    2006-09-15

    An integrated system for biohydrogen production and separation was designed, constructed and operated where biohydrogen was fermented by Thermococcus litoralis, a heterotrophic archaebacterium, and a two-step gas separation process was coupled to recover and concentrate hydrogen. A special liquid seal system was built to deliver, compress and collect the laboratory scale, low volume gas mixtures consisting of hydrogen, nitrogen and carbon dioxide. As a result, gas mixture with 73% high hydrogen content was produced by a combination of a porous and a non-porous gas separation membrane. (author)

  12. Variational Latent Gaussian Process for Recovering Single-Trial Dynamics from Population Spike Trains.

    Science.gov (United States)

    Zhao, Yuan; Park, Il Memming

    2017-05-01

    When governed by underlying low-dimensional dynamics, the interdependence of simultaneously recorded populations of neurons can be explained by a small number of shared factors, or a low-dimensional trajectory. Recovering these latent trajectories, particularly from single-trial population recordings, may help us understand the dynamics that drive neural computation. However, due to the biophysical constraints and noise in the spike trains, inferring trajectories from data is a challenging statistical problem in general. Here, we propose a practical and efficient inference method, the variational latent gaussian process (vLGP). The vLGP combines a generative model with a history-dependent point process observation, together with a smoothness prior on the latent trajectories. The vLGP improves on earlier methods for recovering latent trajectories, which assume either observation models inappropriate for point processes or linear dynamics. We compare and validate vLGP on both simulated data sets and population recordings from the primary visual cortex. In the V1 data set, we find that vLGP achieves substantially higher performance than previous methods for predicting omitted spike trains, as well as capturing both the toroidal topology of visual stimuli space and the noise correlation. These results show that vLGP is a robust method with the potential to reveal hidden neural dynamics from large-scale neural recordings.

  13. A hydrometallurgical process for recovering total metal values from waste monolithic ceramic capacitors.

    Science.gov (United States)

    Prabaharan, G; Barik, S P; Kumar, B

    2016-06-01

    A hydrometallurgical process for recovering the total metal values from waste monolithic ceramic capacitors was investigated. The process parameters such as time, temperature, acid concentration, hydrogen peroxide concentration and other reagents (amount of zinc dust and sodium formate) were optimized. Base metals such as Ba, Ti, Sn, Cu and Ni are leached out in two stages using HCl in stage 1 and HCl with H2O2 in stage 2. More than 99% of leaching efficiency for base metals (Cu, Ni, Ba, Ti and Sn) was achieved. Precious metals such as Au and Pd are leached out using aquaregia and nitric acid was used for the leaching of Ag. Base metals (Ba, Ti, Sn, Cu and Ni) are recovered by selective precipitation using H2SO4 and NaOH solution. In case of precious metals, Au and Pd from the leach solution were precipitated out using sodium metabisulphite and sodium formate, respectively. Sodium chloride was used for the precipitation of Ag from leach solution. Overall recovery for base metals and precious metals are 95% and 92%, respectively. Based on the results of the present study, a process flow diagram was proposed for commercial application.

  14. Innovative Application of Mechanical Activation for Rare Earth Elements Recovering: Process Optimization and Mechanism Exploration

    Science.gov (United States)

    Tan, Quanyin; Deng, Chao; Li, Jinhui

    2016-01-01

    With the rapidly expanding use of fluorescent lamps (FLs) and increasing interest in conservation and sustainable utilization of critical metals such as rare earth elements (REEs), the recovering of REEs from phosphors in waste FLs is becoming a critical environmental and economic issue. To effectively recycle REEs with metallurgical methods, mechanical activation by ball milling was introduced to pretreat the waste phosphors. This current study put the emphasis on the mechanical activation and leaching processes for REEs, and explored the feasibility of the method from both theoretical and practical standpoints. Results showed physicochemical changes of structural destruction and particle size reduction after mechanical activation, leading to the easy dissolution of REEs in the activated samples. Under optimal conditions, dissolution yields of 89.4%, 93.1% and 94.6% for Tb, Eu and Y, respectively, were achieved from activated waste phosphors using hydrochloric acid as the dissolution agent. The shrinking core model proved to be the most applicable for the leaching procedure, with an apparent activation energy of 10.96 ± 2.79 kJ/mol. This novel process indicates that mechanical activation is an efficient method for recovering REEs from waste phosphors, and it has promising potential for REE recovery with low cost and high efficiency.

  15. Controlled release process to recover heterologous glycosylphosphatidylinositol membrane anchored proteins from CHO cells.

    Science.gov (United States)

    Kennard, M L; Food, M R; Jefferies, W A; Piret, J M

    1993-08-05

    A semicontinuous process has been developed to recover heterologous proteins at increased concentrations and purities. Proteins attached to mammalian cell membranes by glycosylphosphatidylinositol (GPI) anchors can be selectively released into the supernatant by the enzyme phosphatidylinositol-phospholipase C (PI-PLC). Chinese hamster ovary (CHO) cells, genetically engineered to express the GPI anchored, human melanoma antigen (p97), were used as a model system. These cells were grown in protein containing growth medium. During a brief harvesting phase the medium was replaced by phosphate buffered saline (PBS) containing 10 mU/mL of PI-PLC and the GPI anchored protein was cleaved from the cell surface and recovered in soluble form at up to 30% purity. After harvesting, the cells were returned to growth medium where the protein was re-expressed within 40 h. The growth rate, viability, and protein production of cells, repeatedly harvested over a 44-day period, were not adversely affected. This continuous cyclic harvesting process allowed recovery of a heterologous protein at high purity and concentrations and could be applied to the recovery of other GPI anchored proteins and genetically engineered GPI anchored fusion proteins. (c) 1993 John Wiley & Sons, Inc.

  16. An environmentally-friendly vacuum reduction metallurgical process to recover germanium from coal fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lingen; Xu, Zhenming, E-mail: zmxu@sjtu.edu.cn

    2016-07-15

    Highlights: • An environmental friendly vacuum reduction metallurgical process is proposed. • Rare and valuable metal germanium from coal fly ash is recycled. • Residues are not a hazardous material and can be further recycled. • A germanium recovery ratio of 94.64% is obtained in pilot scale experiments. - Abstract: The demand for germanium in the field of semiconductor, electronics, and optical devices is growing rapidly; however, the resources of germanium are scarce worldwide. As a secondary material, coal fly ash could be further recycled to retrieve germanium. Up to now, the conventional processes to recover germanium have two problems as follows: on the one hand, it is difficult to be satisfactory for its economic and environmental effect; on the other hand, the recovery ratio of germanium is not all that could be desired. In this paper, an environmentally-friendly vacuum reduction metallurgical process (VRMP) was proposed to recover germanium from coal fly ash. The results of the laboratory scale experiments indicated that the appropriate parameters were 1173 K and 10 Pa with 10 wt% coke addition for 40 min, and recovery ratio germanium was 93.96%. On the basis of above condition, the pilot scale experiments were utilized to assess the actual effect of VRMP for recovery of germanium with parameter of 1473 K, 1–10 Pa and heating time 40 min, the recovery ratio of germanium reached 94.64%. This process considerably enhances germanium recovery, meanwhile, eliminates much of the water usage and residue secondary pollution compared with other conventional processes.

  17. Treatment of exhaust fluorescent lamps to recover yttrium: experimental and process analyses.

    Science.gov (United States)

    De Michelis, Ida; Ferella, Francesco; Varelli, Ennio Fioravante; Vegliò, Francesco

    2011-12-01

    The paper deals with recovery of yttrium from fluorescent powder coming from dismantling of spent fluorescent tubes. Metals are leached by using different acids (nitric, hydrochloric and sulphuric) and ammonia in different leaching tests. These tests show that ammonia is not suitable to recover yttrium, whereas HNO(3) produces toxic vapours. A full factorial design is carried out with HCl and H(2)SO(4) to evaluate the influence of operating factors. HCl and H(2)SO(4) leaching systems give similar results in terms of yttrium extraction yield, but the last one allows to reduce calcium extraction with subsequent advantage during recovery of yttrium compounds in the downstream. The greatest extraction of yttrium is obtained by 20% w/v S/L ratio, 4N H(2)SO(4) concentration and 90°C. Yttrium and calcium yields are nearly 85% and 5%, respectively. The analysis of variance shows that acid concentration alone and interaction between acid and pulp density have a significant positive effect on yttrium solubilization for both HCl and H(2)SO(4) medium. Two models are empirically developed to estimate yttrium and calcium concentration during leaching. Precipitation tests demonstrate that at least the stoichiometric amount of oxalic acid is necessary to recover yttrium efficiently and a pure yttrium oxalate n-hydrate can be produced (99% grade). The process is economically feasible if other components of the fluorescent lamps (glass, ferrous and non-ferrous scraps) are recovered after the equipment dismantling and valorized, besides the cost that is usually paid to recycling companies for collection, treatment or final disposal of such fluorescent powders.

  18. Analysis of volatile organic compounds released during food decaying processes.

    Science.gov (United States)

    Phan, Nhu-Thuc; Kim, Ki-Hyun; Jeon, Eui-Chan; Kim, Uk-Hun; Sohn, Jong Ryeul; Pandey, Sudhir Kumar

    2012-03-01

    A number of volatile organic compounds (VOCs) including acetone, methyl ethyl ketone, toluene, ethylbenzene, m,p-xylene, styrene, and o- xylene released during food decaying processes were measured from three types of decaying food samples (Kimchi (KC), fresh fish (FF), and salted fish (SF)). To begin with, all the food samples were contained in a 100-mL throwaway syringe. These samples were then analyzed sequentially for up to a 14-day period. The patterns of VOC release contrasted sharply between two types of fish (FF and SF) and KC samples. A comparison of data in terms of total VOC showed that the mean values for the two fish types were in the similar magnitude with 280 ± 579 (FF) and 504 ± 1,089 ppmC (SF), while that for KC was much lower with 16.4 ± 7.6 ppmC. There were strong variations in VOC emission patterns during the food decaying processes between fishes and KC that are characterized most sensitively by such component as styrene. The overall results of this study indicate that concentration levels of the VOCs differed significantly between the food types and with the extent of decaying levels through time.

  19. Recovering metals from printed circuit board scrap by a mechanical separation process

    Institute of Scientific and Technical Information of China (English)

    XU Min; LI Guang-ming; HE Wen-zhi; LI Hui

    2008-01-01

    A mechanical separation process was developed for recovering metals from printed circuit board (PCB) scrap; it included three steps: impact crushing, sieving and fluidization separation. The mechanism of the technique was based on the difference in the crushabilities of metallic and nonmetallic materials in the PCBs that led to the concentrated distribution of metals in particles of larger sizes and nonmetals mostly in particles of smaller sizes. It was found that crushed PCB particles from 0.125 mm to 1.000 mm contained about 80% of metals in the PCBs. Metals acquired satisfactory liberation in particles smaller than 0.800 mm. The crushed PCB particles were sieved into fractions of different size ranges. Each fraction separately went through a gas-solid fluidized bed operating at a selected optimal gas velocity for the specific size range. Approximately 95% of metals in printed circuit board particles from 0.125 mm to 0.800 mm was recovered by the gas-fluidized bed separator at the selected optimal gas velocity. However, separation of metals from particles smaller than 0.125 mm was not satisfactory. Further study is needed on metal recovery from fine particles.

  20. Computer Program for Estimation Multivariate Volatility Processes Using DVEC Model of CRM

    Directory of Open Access Journals (Sweden)

    Jelena Z. Minović

    2008-12-01

    Full Text Available This article presents computer program for estimation of multivariate (bivariate and trivariate volatility processes, written in EViews Version 4.1. In order to estimate multivariate volatility processes for analysis of the Serbian financial market, I had to write new subprograms within Eviews software package. The programs are written for the diagonal vector ARCH model (DVEC in bivariate and trivariate versions.

  1. Determination of volatiles produced during radiation processing in Laurus cinnamomum

    Energy Technology Data Exchange (ETDEWEB)

    Salum, D.C.; Araujo, M.M.; Fanaro, G.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Cidade Universitaria, Av. Professor Lineu Prestes 2242, Zip code: 05508-000 Butanta, Sao Paulo, SP (Brazil); Purgatto, E. [Faculdade de Ciencias Farmaceuticas, FCF/USP, Departamento de Alimentos e Nutricao Experimental. Av. Prof. Lineu Prestes, 580 Bloco 14. CEP: 05508-900 Sao Paulo, SP (Brazil)], E-mail: epurgatt@usp.br; Villavicencio, A.L.C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Cidade Universitaria, Av. Professor Lineu Prestes 2242, Zip code: 05508-000 Butanta, Sao Paulo, SP (Brazil)], E-mail: villavic@ipen.br

    2009-07-15

    In order to protect food from pathogenic microorganisms as well as increase its shelf-life, while keeping sensorial properties (e.g., odor and taste), which are important properties required by spice buyers, it is necessary to analyze volatile formation from irradiation of medicinal and food herbs. Possible changes in the odor of these herbs are evaluated by characterizing different radiation doses and effects on sensorial properties, in order to allow better application of the irradiation technology. The aim of the present study was to analyze volatile formation on cinnamon (Laurus cinnamomum) samples after gamma irradiation. These samples were irradiated into plastic packages using a {sup 60}Co facility. Radiation doses applied were 0, 5, 10, 15, 20 and 25 kGy. For the analysis of the samples, solid-phase microextraction (SPME) was applied, while for the analysis of volatile compounds, CG/MS. Spice irradiation showed the highest decrease in volatile compounds. For L. cinnamomum, the irradiation decreased volatile compounds by nearly 56% and 89.5%, respectively, comparing to volatile from a sample which had not been previously irradiated.

  2. Determination of volatiles produced during radiation processing in Laurus cinnamomum

    Science.gov (United States)

    Salum, D. C.; Araújo, M. M.; Fanaro, G. B.; Purgatto, E.; Villavicencio, A. L. C. H.

    2009-07-01

    In order to protect food from pathogenic microorganisms as well as increase its shelf-life, while keeping sensorial properties (e.g., odor and taste), which are important properties required by spice buyers, it is necessary to analyze volatile formation from irradiation of medicinal and food herbs. Possible changes in the odor of these herbs are evaluated by characterizing different radiation doses and effects on sensorial properties, in order to allow better application of the irradiation technology. The aim of the present study was to analyze volatile formation on cinnamon ( Laurus cinnamomum) samples after gamma irradiation. These samples were irradiated into plastic packages using a 60Co facility. Radiation doses applied were 0, 5, 10, 15, 20 and 25 kGy. For the analysis of the samples, solid-phase microextraction (SPME) was applied, while for the analysis of volatile compounds, CG/MS. Spice irradiation showed the highest decrease in volatile compounds. For L. cinnamomum, the irradiation decreased volatile compounds by nearly 56% and 89.5%, respectively, comparing to volatile from a sample which had not been previously irradiated.

  3. Altered food-cue processing in chronically ill and recovered women with anorexia nervosa.

    Science.gov (United States)

    Sanders, Nicole; Smeets, Paul A M; van Elburg, Annemarie A; Danner, Unna N; van Meer, Floor; Hoek, Hans W; Adan, Roger A H

    2015-01-01

    Anorexia nervosa (AN) is a severe mental disorder characterized by food restriction and weight loss. This study aimed to test the model posed by Brooks et al. (2012a,b) that women suffering from chronic AN show decreased food-cue processing activity in brain regions associated with energy balance and food reward (bottom-up; BU) and increased activity in brain regions associated with cognitive control (top-down; TD) when compared with long-term recovered AN (REC) and healthy controls (HC). Three groups of women, 15 AN (mean illness duration 7.8 ± 4.1 years), 14 REC (mean duration of recovery 4.7 ± 2.7 years) and 15 HC viewed alternating blocks of food and non-food images preceded by a short instruction during functional magnetic resonance imaging (fMRI), after fasting overnight. Functional region of interests (fROIs) were defined in BU (e.g., striatum, hippocampus, amygdala, hypothalamus, and cerebellum), TD (e.g., medial and lateral prefrontal cortex, and anterior cingulate), the insula, and visual processing areas (VPA). Food-cue processing activation was extracted from all fROIs and compared between the groups. In addition, functional connectivity between the fROIs was examined by modular partitioning of the correlation matrix of all fROIs. We could not confirm the hypothesis that BU areas are activated to a lesser extent in AN upon visual processing of food images. Among the BU areas the caudate showed higher activation in both patient groups compared to HC. In accordance with Brooks et al.'s model, we did find evidence for increased TD control in AN and REC. The functional connectivity analysis yielded two clusters in HC and REC, but three clusters in AN. In HC, fROIs across BU, TD, and VPA areas clustered; in AN, one cluster span across BU, TD, and insula; one across BU, TD, and VPA areas; and one was confined to the VPA network. In REC, BU, TD, and VPA or VPA and insula clustered. In conclusion, despite weight recovery, neural processing of food

  4. Altered food cue processing in chronically ill and recovered women with Anorexia Nervosa.

    Directory of Open Access Journals (Sweden)

    Nicole eSanders

    2015-02-01

    Full Text Available Anorexia Nervosa (AN is a severe mental disorder characterized by food restriction and weight loss.This study aimed to test the model posed by Brooks et al. (2012, that women suffering from chronic AN show decreased food cue processing activity in brain regions associated with energy balance and food reward (bottom-up; BU and increased activity in brain regions associated with cognitive control (top-down; TD when compared to long term recovered AN (REC and healthy controls (HC. Three groups of women, 15 AN (mean illness duration 7.8 ± 4.1 y, 14 REC (mean duration of recovery 4.7 ± 2.7 yr and 15 HC viewed alternating blocks of food and non-food images preceded by a short instruction during functional magnetic resonance imaging (fMRI, after fasting overnight. Functional ROIs (fROIs were defined in BU (e.g. striatum, hippocampus, amygdala, hypothalamus and cerebellum, TD (e.g. medial and lateral prefrontal cortex, anterior cingulate, the insula and visual processing areas (VPA. Food-cue processing activation was extracted from all fROIs and compared between the groups. In addition, functional connectivity between the fROIs was examined by modular partitioning of the correlation matrix of all fROIs.We could not confirm the hypothesis that BU areas are activated to a lesser extent in AN upon visual processing of food images. Among the BU areas the caudate showed higher activation in both patient groups compared to HC. In accordance with Brooks et al.’s model, we did find evidence for increased TD control in AN and REC. The functional connectivity analysis yielded two clusters in HC and REC, but three clusters in AN. In HC fROIs across BU, TD and VPA areas clustered, in AN one cluster span across BU, TD and insula, one across BU, TD and VPA areas and one was confined to the VPA network. In REC BU, TD and VPA or VPA and insula clustered.In conclusion, despite weight recovery, neural processing of food cues is also altered in recovered AN patient

  5. Altered Food-Cue Processing in Chronically Ill and Recovered Women with Anorexia Nervosa

    Science.gov (United States)

    Sanders, Nicole; Smeets, Paul A. M.; van Elburg, Annemarie A.; Danner, Unna N.; van Meer, Floor; Hoek, Hans W.; Adan, Roger A. H.

    2015-01-01

    Anorexia nervosa (AN) is a severe mental disorder characterized by food restriction and weight loss. This study aimed to test the model posed by Brooks et al. (2012a,b) that women suffering from chronic AN show decreased food-cue processing activity in brain regions associated with energy balance and food reward (bottom-up; BU) and increased activity in brain regions associated with cognitive control (top-down; TD) when compared with long-term recovered AN (REC) and healthy controls (HC). Three groups of women, 15 AN (mean illness duration 7.8 ± 4.1 years), 14 REC (mean duration of recovery 4.7 ± 2.7 years) and 15 HC viewed alternating blocks of food and non-food images preceded by a short instruction during functional magnetic resonance imaging (fMRI), after fasting overnight. Functional region of interests (fROIs) were defined in BU (e.g., striatum, hippocampus, amygdala, hypothalamus, and cerebellum), TD (e.g., medial and lateral prefrontal cortex, and anterior cingulate), the insula, and visual processing areas (VPA). Food-cue processing activation was extracted from all fROIs and compared between the groups. In addition, functional connectivity between the fROIs was examined by modular partitioning of the correlation matrix of all fROIs. We could not confirm the hypothesis that BU areas are activated to a lesser extent in AN upon visual processing of food images. Among the BU areas the caudate showed higher activation in both patient groups compared to HC. In accordance with Brooks et al.’s model, we did find evidence for increased TD control in AN and REC. The functional connectivity analysis yielded two clusters in HC and REC, but three clusters in AN. In HC, fROIs across BU, TD, and VPA areas clustered; in AN, one cluster span across BU, TD, and insula; one across BU, TD, and VPA areas; and one was confined to the VPA network. In REC, BU, TD, and VPA or VPA and insula clustered. In conclusion, despite weight recovery, neural processing of food

  6. Change in Species Diversity during Recovering Process of Evergreen Broad-leaved Fo rest

    Institute of Scientific and Technical Information of China (English)

    WenYuanguang; LiuShirong; ChenFang; HeTatping; LiangHongwen

    2005-01-01

    Evergreen broad-leaved forest is one of the most important vegetation types in China. Because of the human activities, evergreen broad-leaved forest has been destroyed extensively, leading to degraded ecosystem. It is urgent to conserve and restore these natural forests in China.tn this paper, the tendency and rate of species diversity restoration of the evergreen broad-lea ved forest in Darning Mountain has been studied. The main results are as follows:(a) in subtropical mid-mountain area, species diversity in degraded evergreen broad-leaved forest can be restored. Through analyzing b diversity index of communities in different time and space, it was found that the species composition of communities tend to be the same as that in the zonal evergreen broad-leaved forest. (b) The restoration rate of evergreen broad-leaved forest was very fast. Planting Chinese fir after clear-cutting and controlled burning of the forest 178 species appeared in a 60Om2, sample area after 20 years"" natural recovering. Among these species, 58 were tree layer and the height of community reached 18m, The survey suggested that it would take only 20 years for the degraded forest to develop into community composed of light demanding broad-leaved pioneer trees and rain-tolerance broad-leaved trees, and it need another 40-80 years to reach the stage consisting of min-tulerance evergreen broad-leaved trees, (c) Species number increased quickly at the early stage (2-20 years) during vegetation recovering process toward the climax, and decreased at the min-stage (50-60 years ), then maintained a relatively stable level at the late-stage (over 150 years).

  7. Elemental balance of SRF production process: solid recovered fuel produced from municipal solid waste.

    Science.gov (United States)

    Nasrullah, Muhammad; Vainikka, Pasi; Hannula, Janne; Hurme, Markku; Oinas, Pekka

    2016-01-01

    In the production of solid recovered fuel (SRF), certain waste components have excessive influence on the quality of product. The proportion of rubber, plastic (hard) and certain textiles was found to be critical as to the elemental quality of SRF. The mass flow of rubber, plastic (hard) and textiles (to certain extent, especially synthetic textile) components from input waste stream into the output streams of SRF production was found to play the decisive role in defining the elemental quality of SRF. This paper presents the mass flow of polluting and potentially toxic elements (PTEs) in SRF production. The SRF was produced from municipal solid waste (MSW) through mechanical treatment (MT). The results showed that of the total input chlorine content to process, 55% was found in the SRF and 30% in reject material. Of the total input arsenic content, 30% was found in the SRF and 45% in fine fraction. In case of cadmium, lead and mercury, of their total input content to the process, 62%, 38% and 30%, respectively, was found in the SRF. Among the components of MSW, rubber material was identified as potential source of chlorine, containing 8.0 wt.% of chlorine. Plastic (hard) and textile components contained 1.6 and 1.1. wt.% of chlorine, respectively. Plastic (hard) contained higher lead and cadmium content compared with other waste components, i.e. 500 mg kg(-1) and 9.0 mg kg(-1), respectively.

  8. Dynamics of the anaerobic process: Effects of volatile fatty acids

    DEFF Research Database (Denmark)

    Pind, Peter Frode; Angelidaki, Irini; Ahring, Birgitte Kiær

    2003-01-01

    A complex and fast dynamic response of the anaerobic biogas system was observed when the system was subjected to pulses of volatile fatty acids (VFAs). It was shown that a pulse of specific VFAs into a well-functioning continuous stirred tank reactor (CSTR) system operating on cow manure affected...

  9. Recovering Y and Eu from Waste Phosphors Using Chlorination Roasting—Water Leaching Process

    Directory of Open Access Journals (Sweden)

    Mingming Yu

    2016-10-01

    Full Text Available Recovering Y and Eu from waste phosphors using chlorination roasting followed by a water leaching process was investigated in this study. Firstly, by chlorination roasting and water leaching, Y and Eu elements present in waste phosphors were efficiently extracted into a leach solution. Secondly, the majority of the impurities in the solution can be removed by adjusting the pH to 4.5 using a Na2S and NH3·H2O solution. Thirdly, the rare earths can be precipitated afterwards by adding a H2C2O4 solution and adjusting the pH to 2.0. Then rare earth oxides (REOs can be obtained after calcining at 800 °C for 1 h. The characterization study of the waste phosphors and the rare earth oxide products was performed by XRD, XRF, and SEM-EDS analysis to determine the phase and morphological features. Influences of the factors, such as roasting temperatures and time, the addition of ammonium chloride on the roasting of waste phosphors, as well as the pH and the amount of oxalates on the precipitation of Y and Eu, were investigated. The maximum grade (99.84% of mixed rare earth oxides and recovery rate (87.35% of Y and Eu were obtained at the optimized conditions.

  10. Digi-Clima Grid: image processing and distributed computing for recovering historical climate data

    National Research Council Canada - National Science Library

    Sergio Nesmachnow; Gabriel Usera; Francisco Brasileiro

    2015-01-01

    This article describes the Digi-Clima Grid project, whose main goals are to design and implement semi-automatic techniques for digitalizing and recovering historical climate records applying parallel...

  11. Density dependence in a recovering osprey population: demographic and behavioural processes.

    Science.gov (United States)

    Bretagnolle, V; Mougeot, F; Thibault, J-C

    2008-09-01

    1. Understanding how density-dependent and independent processes influence demographic parameters, and hence regulate population size, is fundamental within population ecology. We investigated density dependence in growth rate and fecundity in a recovering population of a semicolonial raptor, the osprey Pandion haliaetus [Linnaeus, 1758], using 31 years of count and demographic data in Corsica. 2. The study population increased from three pairs in 1974 to an average of 22 pairs in the late 1990s, with two distinct phases during the recovery (increase followed by stability) and contrasted trends in breeding parameters in each phase. 3. We show density dependence in population growth rate in the second phase, indicating that the stabilized population was regulated. We also show density dependence in productivity (fledging success between years and hatching success within years). 4. Using long-term data on behavioural interactions at nest sites, and on diet and fish provisioning rate, we evaluated two possible mechanisms of density dependence in productivity, food depletion and behavioural interference. 5. As density increased, both provisioning rate and the size of prey increased, contrary to predictions of a food-depletion mechanism. In the time series, a reduction in fledging success coincided with an increase in the number of non-breeders. Hatching success decreased with increasing local density and frequency of interactions with conspecifics, suggesting that behavioural interference was influencing hatching success. 6. Our study shows that, taking into account the role of non-breeders, in particular in species or populations where there are many floaters and where competition for nest sites is intense, can improve our understanding of density-dependent processes and help conservation actions.

  12. Evolution of volatile aldehydes in Iberian ham matured under different processing conditions.

    Science.gov (United States)

    Martín, L; Timón, M L; Petrón, M J; Ventanas, J; Antequera, T

    2000-04-01

    To evaluate the influence of the Iberian ham processing conditions in the evolution of volatile aldehydes, 35 hams were processed in two plants following different conditions of relative humidity and temperature. For this, free fatty acids, peroxide values and volatile aldehydes were quantified in the hams. The highest increases in free fatty acids were noted during the drying stage in both processing plants. The drying period also revealed the greatest increase in peroxide values, where the highest values were in those hams processed at higher temperatures. The temperature during post-salting and drying had a marked influence on the formation of volatile aldehydes, being responsible for the differences in volatile compounds of matured hams.

  13. Simultaneous determination of volatile and non-volatile nitrosamines in processed meat products by liquid chromatography tandem mass spectrometry using atmospheric pressure chemical ionisation and electrospray ionisation

    DEFF Research Database (Denmark)

    Herrmann, Susan Strange; Duedahl-Olesen, Lene; Granby, Kit

    2014-01-01

    A sensitive, selective and generic method has been developed for the simultaneous determination of the contents (μgkg−1 range) of both volatile nitrosamines (VNA) and non-volatile nitrosamines (NVNA) in processed meat products. The extraction procedure only requires basic laboratory equipment and...

  14. Occurrence of volatile and non-volatile N-nitrosamines in processed meat products and the role of heat treatment

    DEFF Research Database (Denmark)

    Herrmann, Susan Strange; Duedahl-Olesen, Lene; Granby, Kit

    2015-01-01

    Most of the available data on the occurrence of N-nitrosamines (NA) in processed meat products have been generated in the 1980s and 1990s and especially data on the occurrence of non-volatile NA (NVNA) are scarce. Therefore we have studied the levels of volatile nitrosamines (VNA) and NVNA...... in processed meat products on the Danish market (N = 70) and for comparison also products on the Belgian market (N = 20). The effect of heat treatment on the NA levels, in selected samples, was also studied, in order to enable an evaluation of how preparation before consumption affects the levels of NA...... μg kg−1 for one Danish sample and two Belgian samples. Levels of up to 2000 and 4000 μg kg−1 of N-nitroso-thiazolidine-4-carboxylic acid (NTCA) an NVNA occurred in the Danish and the Belgian samples, respectively. The majority of the Danish processed meat products contain NVNA but also VNA occur...

  15. Relation between volatility correlations in financial markets and Omori processes occurring on all scales.

    Science.gov (United States)

    Weber, Philipp; Wang, Fengzhong; Vodenska-Chitkushev, Irena; Havlin, Shlomo; Stanley, H Eugene

    2007-07-01

    We analyze the memory in volatility by studying volatility return intervals, defined as the time between two consecutive fluctuations larger than a given threshold, in time periods following stock market crashes. Such an aftercrash period is characterized by the Omori law, which describes the decay in the rate of aftershocks of a given size with time t by a power law with exponent close to 1. A shock followed by such a power law decay in the rate is here called Omori process. We find self-similar features in the volatility. Specifically, within the aftercrash period there are smaller shocks that themselves constitute Omori processes on smaller scales, similar to the Omori process after the large crash. We call these smaller shocks subcrashes, which are followed by their own aftershocks. We also show that the Omori law holds not only after significant market crashes as shown by Lillo and Mantegna [Phys. Rev. E 68, 016119 (2003)], but also after "intermediate shocks." By appropriate detrending we remove the influence of the crashes and subcrashes from the data, and find that this procedure significantly reduces the memory in the records. Moreover, when studying long-term correlated fractional Brownian motion and autoregressive fractionally integrated moving average artificial models for volatilities, we find Omori-type behavior after high volatilities. Thus, our results support the hypothesis that the memory in the volatility is related to the Omori processes present on different time scales.

  16. Dietary exposure to volatile and non-volatile N-nitrosamines from processed meat products in Denmark.

    Science.gov (United States)

    Herrmann, S S; Duedahl-Olesen, L; Christensen, T; Olesen, P T; Granby, K

    2015-06-01

    Recent epidemiological studies show a positive association between cancer incidence and high intake of processed meat. N-nitrosamines (NAs) in these products have been suggested as one potential causative factor. Most volatile NAs (VNAs) are classified as probable human carcinogens, whereas the carcinogenicity for the majority of the non-volatile NA (NVNA) remains to be elucidated. Danish adults (15-75 years) and children (4-6 years) consume 20 g and 16 g of processed meat per day (95th percentile), respectively. The consumption is primarily accounted for by sausages, salami, pork flank (spiced and boiled) and ham. This consumption results in an exposure to NVNA of 33 and 90 ng kg bw(-1) day(-1) for adults and children, respectively. The exposure to VNA is significantly lower amounting to 0.34 and 1.1 ng kg bw(-1) day(-1) for adults and children, respectively. Based on a BMDL10 of 29 µg kg bw(-1) day(-1) a MOE value ≥17,000 was derived for the exposure to NA known to be carcinogenic (VNA including NSAR), indicating an exposure of low concern. The exposure to the NVNA is substantially higher and if found to be of toxicological significance the exposure may be of concern.

  17. Volatility Discovery

    DEFF Research Database (Denmark)

    Dias, Gustavo Fruet; Scherrer, Cristina; Papailias, Fotis

    The price discovery literature investigates how homogenous securities traded on different markets incorporate information into prices. We take this literature one step further and investigate how these markets contribute to stochastic volatility (volatility discovery). We formally show...... that the realized measures from homogenous securities share a fractional stochastic trend, which is a combination of the price and volatility discovery measures. Furthermore, we show that volatility discovery is associated with the way that market participants process information arrival (market sensitivity...

  18. Microwave Processing of Planetary Surfaces for Volatile Extraction

    Science.gov (United States)

    Ethridge, Edwin C.; Kaukler, William

    2011-01-01

    In-Situ Resource Utilization will be necessary for sustained exploration of space. Volatiles are present in planetary soils, but water by far has the strongest potential for effective utilization. The presence of water at the lunar poles, Mars, and possibly on Phobos opens the possibility of producing LOX for propellant. Water is also a useful radiation shielding material and water (and oxygen) are expendables that are also required for habitation in space. Because of the strong function of water vapor pressure with temperature, heating soil effectively liberates water vapor by sublimation. Microwave energy will penetrate soil and heat from within much more efficiently than heating from the surface with radiant heat. This is especially true under vacuum conditions since the heat transfer rate is very low. The depth of microwave penetration is a strong function of the microwave frequency and to a lesser extent on soil dielectric properties. Methods for measuring the complex electric permittivity and magnetic permeability are being developed and have been measured for some lunar soil simulants at 0.5, 2.45, and 10 GHz from room temperature down to liquid nitrogen temperature. A new method for delivery of microwaves deep into a planetary surface is being prototyped with laboratory experiments and modeled with COMSOL MultiPhysics. We have plans to set up a planetary testbed in a large vacuum chamber in the coming year. Recent results will be presented.

  19. Efficient volatile metal removal from low rank coal in gasification, combustion, and processing systems and methods

    Energy Technology Data Exchange (ETDEWEB)

    Bland, Alan E.; Sellakumar, Kumar Muthusami; Newcomer, Jesse D.

    2017-03-21

    Efficient coal pre-processing systems (69) integrated with gasification, oxy-combustion, and power plant systems include a drying chamber (28), a volatile metal removal chamber (30), recirculated gases, including recycled carbon dioxide (21), nitrogen (6), and gaseous exhaust (60) for increasing the efficiencies and lowering emissions in various coal processing systems.

  20. Testing the maximal rank of the volatility process for continuous diffusions observed with noise

    DEFF Research Database (Denmark)

    Fissler, Tobias; Podolskij, Mark

    2016-01-01

    In this paper, we present a test for the maximal rank of the volatility process in continuous diffusion models observed with noise. Such models are typically applied in mathematical finance, where latent price processes are corrupted by microstructure noise at ultra high frequencies. Using high...

  1. Testing the maximal rank of the volatility process for continuous diffusions observed with noise

    DEFF Research Database (Denmark)

    Fissler, Tobias; Podolskij, Mark

    In this paper, we present a test for the maximal rank of the volatility process in continuous diffusion models observed with noise. Such models are typically applied in mathematical finance, where latent price processes are corrupted by microstructure noise at ultra high frequencies. Using high...

  2. On stochastic integration for volatility modulated Brownian-driven Volterra processes via white noise analysis

    DEFF Research Database (Denmark)

    E. Barndorff-Nielsen, Ole; Benth, Fred Espen; Szozda, Benedykt

    This paper generalizes the integration theory for volatility modulated Brownian-driven Volterra processes onto the space G* of Potthoff-Timpel distributions. Sufficient conditions for integrability of generalized processes are given, regularity results and properties of the integral are discussed...

  3. Efficient volatile metal removal from low rank coal in gasification, combustion, and processing systems and methods

    Science.gov (United States)

    Bland, Alan E.; Sellakumar, Kumar Muthusami; Newcomer, Jesse D.

    2017-03-21

    Efficient coal pre-processing systems (69) integrated with gasification, oxy-combustion, and power plant systems include a drying chamber (28), a volatile metal removal chamber (30), recirculated gases, including recycled carbon dioxide (21), nitrogen (6), and gaseous exhaust (60) for increasing the efficiencies and lowering emissions in various coal processing systems.

  4. On stochastic integration for volatility modulated Brownian-driven Volterra processes via white noise analysis

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole E.; Benth, Fred Espen; Szozda, Benedykt

    This paper generalizes the integration theory for volatility modulated Brownian-driven Volterra processes onto the space G∗ of Potthoff--Timpel distributions. Sufficient conditions for integrability of generalized processes are given, regularity results and properties of the integral are discussed...

  5. Dietary exposure to volatile and non-volatile N-nitrosamines from processed meat products in Denmark

    DEFF Research Database (Denmark)

    Herrmann, Susan Strange; Duedahl-Olesen, Lene; Christensen, Tue

    2015-01-01

    the carcinogenicity for the majority of the non-volatile NA (NVNA) remains to be elucidated. Danish adults (15–75 years) and children (4–6 years) consume 20 g and 16 g of processed meat per day (95th percentile), respectively. The consumption is primarily accounted for by sausages, salami, pork flank (spiced...... and boiled) and ham. This consumption results in an exposure to NVNA of 33 and 90 ng kg bw−1 day−1 for adults and children, respectively. The exposure to VNA is significantly lower amounting to 0.34 and 1.1 ng kg bw−1 day−1 for adults and children, respectively. Based on a BMDL10 of 29 µg kg bw−1 day−1 a MOE...

  6. Pricing foreign equity option under stochastic volatility tempered stable Lévy processes

    Science.gov (United States)

    Gong, Xiaoli; Zhuang, Xintian

    2017-10-01

    Considering that financial assets returns exhibit leptokurtosis, asymmetry properties as well as clustering and heteroskedasticity effect, this paper substitutes the logarithm normal jumps in Heston stochastic volatility model by the classical tempered stable (CTS) distribution and normal tempered stable (NTS) distribution to construct stochastic volatility tempered stable Lévy processes (TSSV) model. The TSSV model framework permits infinite activity jump behaviors of return dynamics and time varying volatility consistently observed in financial markets through subordinating tempered stable process to stochastic volatility process, capturing leptokurtosis, fat tailedness and asymmetry features of returns. By employing the analytical characteristic function and fast Fourier transform (FFT) technique, the formula for probability density function (PDF) of TSSV returns is derived, making the analytical formula for foreign equity option (FEO) pricing available. High frequency financial returns data are employed to verify the effectiveness of proposed models in reflecting the stylized facts of financial markets. Numerical analysis is performed to investigate the relationship between the corresponding parameters and the implied volatility of foreign equity option.

  7. Distribution of colored carotenoids between light-harvesting complexes in the process of recovering carotenoid biosynthesis in Ectothiorhodospira haloalkaliphila cells.

    Science.gov (United States)

    Ashikhmin, Aleksandr; Makhneva, Zoya; Bolshakov, Maksim; Moskalenko, Andrey

    2014-12-01

    The processes of recovering colored-carotenoid (Car) biosynthesis in Car-less cells of the purple sulfur bacterium Ectothiorhodospira haloalkaliphila grown with diphenylamine (DPA-cells) have been studied. It has been found that (1) the rate of recovering colored-Car biosynthesis in the lag-phase is far ahead of the growth rate of the cells themselves; (2) several Cars (ζ-carotene, neurosporene etc.) act as intermediates in Car biosynthesis; (3) because filling the "empty" Car pockets in the LH1-RC complexes is faster than in LH2, available spirilloxanthin is preferentially incorporated into the nascent LH1-RC core particles; (4) as a consequence of the resulting lack of spirilloxanthin availability, the biosynthetic intermediates (anhydrorhodovibrin, rhodopin and lycopene) fill the empty nascent LH2 Car pockets. In the present report, we further discuss the process of colored Car incorporation into LH complexes during the recovery of Car biosynthesis in the DPA-cells of Ect.haloalkaliphila.

  8. Hayabusa2 Sample Catcher and Container: Metal-Seal System for Vacuum Encapsulation of Returned Samples with Volatiles and Organic Compounds Recovered from C-Type Asteroid Ryugu

    Science.gov (United States)

    Okazaki, Ryuji; Sawada, Hirotaka; Yamanouchi, Shinji; Tachibana, Shogo; Miura, Yayoi N.; Sakamoto, Kanako; Takano, Yoshinori; Abe, Masanao; Itoh, Shoichi; Yamada, Keita; Yabuta, Hikaru; Okamoto, Chisato; Yano, Hajime; Noguchi, Takaaki; Nakamura, Tomoki; Nagao, Keisuke

    2017-07-01

    The spacecraft Hayabusa2 was launched on December 3, 2014, to collect and return samples from a C-type asteroid, 162173 Ryugu (provisional designation, 1999 JU3). It is expected that the samples collected contain organic matter and water-bearing minerals and have key information to elucidate the origin and history of the Solar System and the evolution of bio-related organics prior to delivery to the early Earth. In order to obtain samples with volatile species without terrestrial contamination, based on lessons learned from the Hayabusa mission, the sample catcher and container of Hayabusa2 were refined from those used in Hayabusa. The improvements include (1) a mirror finish of the inner wall surface of the sample catcher and the container, (2) adoption of an aluminum metal sealing system, and (3) addition of a gas-sampling interface for gas collection and evacuation. The former two improvements were made to limit contamination of the samples by terrestrial atmosphere below 1 Pa after the container is sealed. The gas-sampling interface will be used to promptly collect volatile species released from the samples in the sample container after sealing of the container. These improvements maintain the value of the returned samples.

  9. Hayabusa2 Sample Catcher and Container: Metal-Seal System for Vacuum Encapsulation of Returned Samples with Volatiles and Organic Compounds Recovered from C-Type Asteroid Ryugu

    Science.gov (United States)

    Okazaki, Ryuji; Sawada, Hirotaka; Yamanouchi, Shinji; Tachibana, Shogo; Miura, Yayoi N.; Sakamoto, Kanako; Takano, Yoshinori; Abe, Masanao; Itoh, Shoichi; Yamada, Keita; Yabuta, Hikaru; Okamoto, Chisato; Yano, Hajime; Noguchi, Takaaki; Nakamura, Tomoki; Nagao, Keisuke

    2016-10-01

    The spacecraft Hayabusa2 was launched on December 3, 2014, to collect and return samples from a C-type asteroid, 162173 Ryugu (provisional designation, 1999 JU3). It is expected that the samples collected contain organic matter and water-bearing minerals and have key information to elucidate the origin and history of the Solar System and the evolution of bio-related organics prior to delivery to the early Earth. In order to obtain samples with volatile species without terrestrial contamination, based on lessons learned from the Hayabusa mission, the sample catcher and container of Hayabusa2 were refined from those used in Hayabusa. The improvements include (1) a mirror finish of the inner wall surface of the sample catcher and the container, (2) adoption of an aluminum metal sealing system, and (3) addition of a gas-sampling interface for gas collection and evacuation. The former two improvements were made to limit contamination of the samples by terrestrial atmosphere below 1 Pa after the container is sealed. The gas-sampling interface will be used to promptly collect volatile species released from the samples in the sample container after sealing of the container. These improvements maintain the value of the returned samples.

  10. Characterization and extraction of volatile compounds from pineapple (Ananas comosus L. Merril processing residues

    Directory of Open Access Journals (Sweden)

    Lília Calheiros de Oliveira Barretto

    2013-12-01

    Full Text Available The aim of this study was to extract and identify volatile compounds from pineapple residues generated during concentrated juice processing. Distillates of pineapple residues were obtained using the following techniques: simple hydrodistillation and hydrodistillation by passing nitrogen gas. The volatile compounds present in the distillates were captured by the solid-phase microextraction technique. The volatile compounds were identified in a system of high resolution gas chromatography system coupled with mass spectrometry using a polyethylene glycol polar capillary column as stationary phase. The pineapple residues constituted mostly of esters (35%, followed by ketones (26%, alcohols (18%, aldehydes (9%, acids (3% and other compounds (9%. Odor-active volatile compounds were mainly identified in the distillate obtained using hydrodistillation by passing nitrogen gas, namely decanal, ethyl octanoate, acetic acid, 1-hexanol, and ketones such as γ-hexalactone, γ-octalactone, δ-octalactone, γ-decalactone, and γ-dodecalactone. This suggests that the use of an inert gas and lower temperatures helped maintain higher amounts of flavor compounds. These data indicate that pineapple processing residue contained important volatile compounds which can be extracted and used as aroma enhancing products and have high potential for the production of value-added natural essences.

  11. Potential Signatures of Semi-volatile Compounds Associated With Nuclear Processing

    Energy Technology Data Exchange (ETDEWEB)

    Probasco, Kathleen M.; Birnbaum, Jerome C.; Maughan, A. D.

    2002-06-01

    Semi-volatile chemicals associated with nuclear processes (e.g., the reprocessing of uranium to produce plutonium for nuclear weapons, or the separation of actinides from processing waste streams), can provide sticky residues or signatures that will attach to piping, ducting, soil, water, or other surface media. Volatile compounds, that are more suitable for electro-optical sensing, have been well studied. However, the semi-volatile compounds have not been well documented or studied. A majority of these semi-volatile chemicals are more robust than typical gaseous or liquid chemicals and can have lifetimes of several weeks, months, or years in the environment. However, large data gaps exist concerning these potential signature compounds and more research is needed to fill these data gaps so that important signature information is not overlooked or discarded. This report investigates key semi-volatile compounds associated with nuclear separations, identifies available chemical and physical properties, and discusses the degradation products that would result from hydrolysis, radiolysis and oxidation reactions on these compounds.

  12. Process for recovering uranium from waste hydrocarbon oils containing the same. [Uranium contaminated lubricating oils from gaseous diffusion compressors

    Science.gov (United States)

    Conrad, M.C.; Getz, P.A.; Hickman, J.E.; Payne, L.D.

    1982-06-29

    The invention is a process for the recovery of uranium from uranium-bearing hydrocarbon oils containing carboxylic acid as a degradation product. In one aspect, the invention comprises providing an emulsion of water and the oil, heating the same to a temperature effecting conversion of the emulsion to an organic phase and to an acidic aqueous phase containing uranium carboxylate, and recovering the uranium from the aqueous phase. The process is effective, simple and comparatively inexpensive. It avoids the use of toxic reagents and the formation of undesirable intermediates.

  13. Utilization of recovered nitrogen from hydrothermal carbonization process by Arthrospira platensis.

    Science.gov (United States)

    Yao, Changhong; Pan, Yanfei; Lu, Hongbin; Wu, Peichun; Meng, Yingying; Cao, Xupeng; Xue, Song

    2016-07-01

    In the context of sustainable cultivation of microalgae, the present study focused on the use of nitrogen from the hot-water extracted biomass residue of Arthrospira platensis by hydrothermal carbonization (HTC) and the sequential cultivation of the same alga with the HTC aqueous phase (AP). Nearly 90% of the nitrogen recovered from HTC into AP was in the organic form. Under nitrogen-limited condition with HTCAP as nitrogen source the yield and content of carbohydrate were enhanced by 21% and 15% respectively compared with that under the same nitrogen level provided by NaNO3, which entitled HTCAP for the substitution of conventional nitrate. In the same way pilot-scale cultivation of A. platensis in raceway ponds outdoors demonstrated that carbohydrate content of 43.8% DW and productivity of 10.3g/m(2)/d was achieved. Notably 54% of organic nitrogen in the HTCAP could be recycled by cultivation of pre-nitrogen starved A. platensis as seeds under nitrogen limitation.

  14. Low-temperature process steps for realization of non-volatile memory devices

    NARCIS (Netherlands)

    Brunets, I.; Boogaard, A.; Aarnink, A.A.I.; Kovalgin, A.Y.; Wolters, R.A.M.; Holleman, J.; Schmitz, J.

    2007-01-01

    In this work, the low-temperature process steps required for the realization of nano-crystal non-volatile memory cells are discussed. An amorphous silicon film, crystallized using a diode pumped solid state green laser irradiating at 532 nm, is proposed as an active layer. The deposition of the subs

  15. Treatment of volatile organic contaminants in a vertical flow filter: Relevance of different removal processes

    NARCIS (Netherlands)

    De Biase, C.; Reger, D.; Schmidt, A.; Jechalke, S.; Reiche, N.; Martínez-Lavanchy, P.M.; Rosell, M.; Van Afferden, M.; Maier, U.; Oswald, S.E.; Thullner, M.

    2011-01-01

    Vertical flow filters and vertical flow constructed wetlands are established wastewater treatment systems and have also been proposed for the treatment of contaminated groundwater. This study investigates the removal processes of volatile organic compounds in a pilot-scale vertical flow filter. The

  16. Process model for ammonia volatilization from anaerobic swine lagoons incorporating varying wind speeds and biogas bubbling

    Science.gov (United States)

    Ammonia volatilization from treatment lagoons varies widely with the total ammonia concentration, pH, temperature, suspended solids, atmospheric ammonia concentration above the water surface, and wind speed. Ammonia emissions were estimated with a process-based mechanistic model integrating ammonia ...

  17. Treatment of volatile organic contaminants in a vertical flow filter: Relevance of different removal processes

    NARCIS (Netherlands)

    De Biase, C.; Reger, D.; Schmidt, A.; Jechalke, S.; Reiche, N.; Martínez-Lavanchy, P.M.; Rosell, M.; Van Afferden, M.; Maier, U.; Oswald, S.E.; Thullner, M.

    2011-01-01

    Vertical flow filters and vertical flow constructed wetlands are established wastewater treatment systems and have also been proposed for the treatment of contaminated groundwater. This study investigates the removal processes of volatile organic compounds in a pilot-scale vertical flow filter.

  18. Process of carbothermal self-recovering of disperse Fe-C waste materials of metallurgical production modelling

    Directory of Open Access Journals (Sweden)

    Володимир Олександрович Маслов

    2015-10-01

    Full Text Available Investigation of carbothermic self-recovering kinetics of metallurgical production Fe-C waste materials has been continued in this work for model monodisperse wustite-carbon and magnetite-carbon samples. On the strength of the results of differential thermal analysis the temperature of the beginning of the interaction in polydisperse material was determined. It should be more than 960oC. Kinetic curves of carbothermic self-recovering at 970oC and 1050oC were obtained on monodisperse model samples. During the study of high-temperature processing kinetics of Fe-C waste materials the amount of removed oxygen was determined from the volume and composition of the emitted gas phase. The method comprising simultaneous volume - dynamic and gas analyses was used. Analysis of the results showed that with increase in temperature the maximum rate of oxygen removal was achieved faster and had greater value. Analysis of the gas phase showed that at the initial stage of the process CO content was low over the whole operating temperature range. Then it increased and CO/CO2 ratio remained constant till the experiment was over. The concentration of CO for all temperatures being studied was about 75%, the rest was CO2. It convincingly indicated that the process is out of equilibrium with the gas phase and shifting towards CO2 formation. It was found that the completion of the first stage of the process is characterized by virtually zero magnetic properties of the material, i.e. by obtaining pure wustite. The obtained results confirmed the two-stage scheme of carbothermic process of dispersed Fe-C waste materials self-recovering and its topochemical nature. Studies of electrophysical and magnetic properties of the samples after the carbothermic self-recovering have been made. We found that for the studied materials the value of the specific saturation magnetization keeps growing during the process, reaching 179 A×m2/kg for wustite-carbon sample. The obtained

  19. Application of pyrolysis process to remove and recover liquid crystal and films from waste liquid crystal display glass.

    Science.gov (United States)

    Lu, Rixin; Ma, En; Xu, Zhenming

    2012-12-01

    Liquid crystal display (LCD) glass mainly consists of polarizing film, liquid crystal and glass substrate. Removing and recovering the liquid crystal and films from the LCD glass effectively has important significance for recovering the other parts. This study proposed a pyrolysis process to recover the organic parts from LCD glass. Through thermal gravimetric analysis, the pyrolysis temperature of the LCD glass could be chosen at 850 K. The removal rate of organic parts from LCD glass reached 87.87 wt%. Pyrolysis products consisted of 66.82 wt% oils, 21.01 wt% gaseous and 12.13 wt% residues. In addition, the oils contained 46.27 wt% acetic acid and 32.94 wt% triphenyl phosphate. Then, the pyrolysis mechanisms and products sources of the liquid crystal glass have been analyzed based on the information of bonds energy. The pyrolysis mechanism analysis proved that the products mainly consisted of acetic acid, triphenyl phosphate and C, which is consistent to the results of GC-MS analysis. A reasonable way has been put forward to recycle the pyrolysis products: acetic acid and triphenyl phosphate can be collected by distillation, the rest oils and gases can be used as fuel and the remained glass can be used to extract indium and to produce building materials.

  20. Evaluation of recovering the "Tuvacobalt” Mining and Processing Complex: accounting the ecology factor

    Directory of Open Access Journals (Sweden)

    David F. Dabiev

    2016-06-01

    Full Text Available The article describes the various options for recovery of the "Tuvacobalt” Mining and Processing Complex that worked on the mineral resources base of Khovu-Aksy nickel-cobalt deposit between 1970 and 1990’s. It shows that in case of revival combined with innovative technologies the project will have a relatively higher economic efficiency.

  1. Enterobacteriaceae and related organisms recovered from biofilms in a commercial shell egg processing facility.

    Science.gov (United States)

    During six visits, biofilms from egg contact and non-contact surfaces in a commercial shell egg processing facility were sampled. Thirty-five different sample sites were selected: Pre-wash and wash tanks (lids, screens, tank interiors, nozzle guards), post-wash spindles, blower filters, belts (far...

  2. Free amino acids and other non-volatile compounds formed during processing of Iberian ham.

    Science.gov (United States)

    Martín, L; Antequera, T; Ventanas, J; Benítez-Donoso, R; Córdoba, J J

    2001-12-01

    Fifty-five legs from Iberian pigs were traditionally processed into dry cured hams. Free amino acids and other non-volatile compounds in the water-soluble fraction from the biceps femoris muscle were analyzed by HPLC. At the drying stage and in the last months in the cellar the largest increases in these water-soluble compounds took place. There was a clear influence on free amino acid formation of salt content and on the formation of peptides of the temperature at each processing stage. As the amount of non-volatile compounds in the water-soluble fraction increases with processing time, their determination could provide a maturation index for Iberian ham.

  3. Virtual volatility

    Science.gov (United States)

    Silva, A. Christian; Prange, Richard E.

    2007-03-01

    We introduce the concept of virtual volatility. This simple but new measure shows how to quantify the uncertainty in the forecast of the drift component of a random walk. The virtual volatility also is a useful tool in understanding the stochastic process for a given portfolio. In particular, and as an example, we were able to identify mean reversion effect in our portfolio. Finally, we briefly discuss the potential practical effect of the virtual volatility on an investor asset allocation strategy.

  4. Virtual volatility

    OpenAIRE

    A. Christian Silva; Prange, Richard E.

    2006-01-01

    We introduce the concept of virtual volatility. This simple but new measure shows how to quantify the uncertainty in the forecast of the drift component of a random walk. The virtual volatility also is a useful tool in understanding the stochastic process for a given portfolio. In particular, and as an example, we were able to identify mean reversion effect in our portfolio. Finally, we briefly discuss the potential practical effect of the virtual volatility on an investor asset allocation st...

  5. Adsorption process to recover hydrogen from feed gas mixtures having low hydrogen concentration

    Science.gov (United States)

    Golden, Timothy Christopher; Weist, Jr., Edward Landis; Hufton, Jeffrey Raymond; Novosat, Paul Anthony

    2010-04-13

    A process for selectively separating hydrogen from at least one more strongly adsorbable component in a plurality of adsorption beds to produce a hydrogen-rich product gas from a low hydrogen concentration feed with a high recovery rate. Each of the plurality of adsorption beds subjected to a repetitive cycle. The process comprises an adsorption step for producing the hydrogen-rich product from a feed gas mixture comprising 5% to 50% hydrogen, at least two pressure equalization by void space gas withdrawal steps, a provide purge step resulting in a first pressure decrease, a blowdown step resulting in a second pressure decrease, a purge step, at least two pressure equalization by void space gas introduction steps, and a repressurization step. The second pressure decrease is at least 2 times greater than the first pressure decrease.

  6. Lipid oxidation in baked products: impact of formula and process on the generation of volatile compounds.

    Science.gov (United States)

    Maire, Murielle; Rega, Barbara; Cuvelier, Marie-Elisabeth; Soto, Paola; Giampaoli, Pierre

    2013-12-15

    This paper investigates the effect of ingredients on the reactions occurring during the making of sponge cake and leading to the generation of volatile compounds related to flavour quality. To obtain systems sensitive to lipid oxidation (LO), a formulation design was applied varying the composition of fatty matter and eggs. Oxidation of polyunsaturated fatty acids (PUFA) and formation of related volatile compounds were followed at the different steps of cake-making. Optimised dynamic Solid Phase Micro Extraction was applied to selectively extract either volatile or semi-volatile compounds directly from the baking vapours. We show for the first time that in the case of alveolar baked products, lipid oxidation occurs very early during the step of dough preparation and to a minor extent during the baking process. The generation of lipid oxidation compounds depends on PUFA content and on the presence of endogenous antioxidants in the raw matter. Egg yolk seemed to play a double role on reactivity: protecting unsaturated lipids from oxidation and being necessary to generate a broad class of compounds of the Maillard reaction during baking and linked to the typical flavour of sponge cake.

  7. The requirements for processing tritium recovered from liquid lithium blankets: The blanket interface

    Energy Technology Data Exchange (ETDEWEB)

    Clemmer, R.G.; Finn, P.A.; Greenwood, L.R.; Grimm, T.L.; Sze, D.K.; Bartlit, J.R.; Anderson, J.L.; Yoshida, H.; Naruse

    1988-03-01

    We have initiated a study to define a blanket processing mockup for Tritium Systems Test Assembly. Initial evaluation of the requirements of the blanket processing system have been started. The first step of the work is to define the condition of the gaseous tritium stream from the blanket tritium recovery system. This report summarizes this part of the work for one particular blanket concept, i.e., a self-cooled lithium blanket. The total gas throughput, the hydrogen to tritium ratio, the corrosive chemicals, and the radionuclides are defined. The key discoveries are: the throughput of the blanket gas stream (including the helium carrier gas) is about two orders of magnitude higher than the plasma exhaust stream;the protium to tritium ratio is about 1, the deuterium to tritium ratio is about 0.003;the corrosion chemicals are dominated by halides;the radionuclides are dominated by C-14, P-32, and S-35;their is high level of nitrogen contamination in the blanket stream. 77 refs., 6 figs., 13 tabs.

  8. Are volatility correlations in financial markets related to Omori processes occurring on all scales?

    CERN Document Server

    Weber, P; Stanley, H E; Vodenska-Chitkushev, I; Wang, F; Havlin, Shlomo; Vodenska-Chitkushev, Irena; Wang, Fengzhong; Weber, Philipp

    2006-01-01

    We analyze the memory in volatility by studying volatility return intervals, defined as the time between two consecutive fluctuations larger than a given threshold, in time periods following stock market crashes. Such an aftercrash period is characterized by the Omori law, which describes the decay in the rate of aftershocks of a given size with time t by a power law with exponent close to 1. A shock followed by such a power law decay in the rate is here called Omori process. Studying several aftercrash time series, we show that the Omori law holds not only after significant market crashes, but also after ``intermediate shocks''. Moreover, we find self-similar features in the volatility. Specifically, within the aftercrash period there are smaller shocks that themselves constitute Omori processes on smaller scales, similar to the Omori process after the large crash. We call these smaller shocks subcrashes, which are followed by their own aftershocks. We also find similar Omori processes after intermediate cra...

  9. Methods to recover value-added coproducts from dry grind processing of grains into fuel ethanol.

    Science.gov (United States)

    Liu, Keshun; Barrows, Frederic T

    2013-07-31

    Three methods are described to fractionate condensed distillers solubles (CDS) into several new coproducts, including a protein-mineral fraction and a glycerol fraction by a chemical method; a protein fraction, an oil fraction and a glycerol-mineral fraction by a physical method; or a protein fraction, an oil fraction, a mineral fraction, and a glycerol fraction by a physicochemical method. Processing factors (ethanol concentration and centrifuge force) were also investigated. Results show that the three methods separated CDS into different fractions, with each fraction enriched with one or more of the five components (protein, oil, ash, glycerol and other carbohydrates) and thus having different targeted end uses. Furthermore, because glycerol, a hygroscopic substance, was mostly shifted to the glycerol or glycerol-mineral fraction, the other fractions had much faster moisture reduction rates than CDS upon drying in a forced air oven at 60 °C. Thus, these methods could effectively solve the dewatering problem of CDS, allowing elimination of the current industrial practice of blending distiller wet grains with CDS for drying together and production of distiller dried grains as a standalone coproduct in addition to a few new fractions.

  10. [Effects of processing methods on the amounts of volatile oil of nutmeg and on isolation and characterization of the volatile oil constituents].

    Science.gov (United States)

    Li, T; Zhou, J; Xu, Z; Pan, J; Mao, S

    1990-07-01

    In this paper, the authors investigated the effects of various processing methods, i.e., scalding in hot purified talc, simmering wrapped in flour in hot purified talc and stir-frying in smoking wheat bran, on nutmeg (Semen Myristicae) in terms of the quantities of the volatile oil. The experimental results revealed that the amounts of volatile oil contained in nutmeg vary remarkably with the lengths of cooking time and the fluctuation of temperature. Detected by GC-MS-computer, 32 compounds of nutmeg were characterized, and their contents were determined by GC respectively.

  11. Occurence and dietary exposure of volatile and non-volatile N-Nitrosamines in processed meat products

    DEFF Research Database (Denmark)

    Herrmann, Susan Strange; Duedahl-Olesen, Lene; Granby, Kit

    a high level of consumer protection Denmark obtains National low limits of the nitrite use in meat products. An estimation of the dietary exposure to volatile NAs (VNA) and non-volatile NAs (NVNA) is necessary when performing a risk assessment of the use of nitrite and nitrate for meat preservation.......Nitrite and nitrate have for many decades been used for preservation of meat. However, nitrite can react with secondary amines in meat to form N-Nitrosamines (NAs), many of which have been shown to be genotoxic1 . The use of nitrite therefore ought to be limited as much as possible. To maintain...

  12. Automated Signal Processing Applied to Volatile-Based Inspection of Greenhouse Crops

    Directory of Open Access Journals (Sweden)

    Eldert van Henten

    2010-07-01

    Full Text Available Gas chromatograph–mass spectrometers (GC-MS have been used and shown utility for volatile-based inspection of greenhouse crops. However, a widely recognized difficulty associated with GC-MS application is the large and complex data generated by this instrument. As a consequence, experienced analysts are often required to process this data in order to determine the concentrations of the volatile organic compounds (VOCs of interest. Manual processing is time-consuming, labour intensive and may be subject to errors due to fatigue. The objective of this study was to assess whether or not GC-MS data can also be automatically processed in order to determine the concentrations of crop health associated VOCs in a greenhouse. An experimental dataset that consisted of twelve data files was processed both manually and automatically to address this question. Manual processing was based on simple peak integration while the automatic processing relied on the algorithms implemented in the MetAlignTM software package. The results of automatic processing of the experimental dataset resulted in concentrations similar to that after manual processing. These results demonstrate that GC-MS data can be automatically processed in order to accurately determine the concentrations of crop health associated VOCs in a greenhouse. When processing GC-MS data automatically, noise reduction, alignment, baseline correction and normalisation are required.

  13. Occurrence and antimicrobial susceptibility of Salmonella isolates recovered from the pig slaughter process in Romania.

    Science.gov (United States)

    Morar, Adriana; Sala, Claudia; Imre, Kálmán

    2015-01-15

    Reported human salmonellosis cases have increased in Romania. Antibiotic susceptibility testing of Salmonella strains isolated from pork and chicken meat indicate a worrying multidrug resistance pattern. This study aimed to investigate the occurrence of Salmonella and to evaluate the antibiotic resistance of Salmonella strains in a pig slaughterhouse-processing complex, which receives animals from 30% of the large industrialized swine farms in Romania. A total of 108 samples, including pork (n = 47), packaged pork products (n = 44), scald water sludge (n = 8), and detritus from the hair removal machine of the slaughterhouse (n = 9) were examined for the presence of Salmonella through standard methods. The antibiotic susceptibility of the isolated strains to 17 antibiotics was tested using the Vitek 2 system. Twenty-six (24.1%) samples were found to be Salmonella positive; this included 25.5% of meat samples and 15.9% of packaged products, as well as samples from two different points of the slaughter (41.2%). Resistance was observed against tetracycline (61.5%), ampicillin (50%), piperacillin (50%), trimethoprim-sulfamethoxazole (34.6%), amoxicillin/clavulanic acid (26.9%), nitrofurantion (23.1%), cefazolin (15.4%), piperacillin/tazobactam (7.7%), imipenem (3.8%), ciprofloxacin (3.8%), and norfloxacin (3.8%). No resistance towards cefoxitin, cefotaxime, ceftazidime, cefepime, amikacin, and gentamicin was found. Our study demonstrated the occurrence of multidrug-resistant Salmonella strains in the investigated pork production complex and highlighted it as a potential source of human infections. The results demonstrate the seriousness of antibiotic resistance of Salmonella in Romania, while providing a useful insight for the treatment of human salmonellosis by specialists.

  14. Studies on the lipid constituents of grape seeds recovered from pomace resulting from white grape processing

    Directory of Open Access Journals (Sweden)

    El-Shami, S. M.

    1992-06-01

    Full Text Available Studies on the lipid constituents of grape seeds, produced as by-product from white grape processing, were carried out. Gas liquid chromatography was used to determine the composition of fatty acid methyl esters and sterol silyl derivatives of the oil. The oil was found to contain appreciable amount of unsaturated fatty acids, namely, oleic and linoleic acids, however, linolenic acid was not detected. Saturated fatty acids, namely, palmitic and stearic were found to be present in reasonable amounts. Myristic, palmitoleic, eicosanoic and eicosadienoic acids were detected as minor components. Isofucosterol was found among the other sterol constituents namely, campesterol, stigmasterol and beta-sitosterol. HPLC analysis of the oil for determination of tocopherols, showed the presence of alpha-and gamma-tocotrienols, and alpha-and gamma-tocopherols to the extent of 53.2, 28.6, 16,4 and 1,8% respectively. The total tocopherols content of the oil was 470 ppm. The defatted meal of grape seeds was found to contain 24,6% protein which contained large proportions of all the essential amino acids as determined by amino acid analyzer.

    Se han realizado estudios sobre los constituyentes lipidiaos de semillas de uva producidas como subproducto del procesado de uva blanca. La cromatografía gas-líquido se usó para determinar la composición de esteres metílicos de ácidos grasos y silil derivados esteroles del aceite. Se observó que el aceite contenía cantidades apreciables de ácidos grasos insaturados, principalmente ácidos oleico y linoleico, no siendo sin embargo detectado el ácido linolénico. Se encontraron en cantidades razonables ácidos grasos saturados, principalmente, palmítico y esteárico. Como componentes minoritarios se detectaron los ácidos mirístico, palmitoleico, eicosanoico y eicosadienoico. El isofucosterol apareció junto a otros esteroles, principalmente, campesterol, estigmasterol y beta-sitosterol. El análisis por HPLC

  15. Unstable volatility

    DEFF Research Database (Denmark)

    Casas, Isabel; Gijbels, Irène

    2012-01-01

    The objective of this paper is to introduce the break-preserving local linear (BPLL) estimator for the estimation of unstable volatility functions for independent and asymptotically independent processes. Breaks in the structure of the conditional mean and/or the volatility functions are common i...

  16. Unstable volatility

    DEFF Research Database (Denmark)

    Casas, Isabel; Gijbels, Irène

    2012-01-01

    The objective of this paper is to introduce the break-preserving local linear (BPLL) estimator for the estimation of unstable volatility functions for independent and asymptotically independent processes. Breaks in the structure of the conditional mean and/or the volatility functions are common i...

  17. FIELD DEMONSTRATION OF A MEMBRANE PROCESS TO RECOVER HEAVY HYDROCARBONS AND TO REMOVE WATER FROM NATURAL GAS

    Energy Technology Data Exchange (ETDEWEB)

    R. Baker; T. Hofmann; J. Kaschemekat; K.A. Lokhandwala; Membrane Group; Module Group; Systems Group

    2001-01-11

    The objective of this project is to design, construct and field demonstrate a 3-MMscfd membrane system to recover natural gas liquids (NGL) and remove water from raw natural gas. An extended field test to demonstrate system performance under real-world conditions is required to convince industry users of the efficiency and reliability of the process. The system will be designed and fabricated by Membrane Technology and Research, Inc. (MTR) and then installed and operated at British Petroleum (BP)-Amoco's Pascagoula, MS plant. The Gas Research Institute will partially support the field demonstration and BP-Amoco will help install the unit and provide onsite operators and utilities. The gas processed by the membrane system will meet pipeline specifications for dewpoint and Btu value and can be delivered without further treatment to the pipeline. Based on data from prior membrane module tests, the process is likely to be significantly less expensive than glycol dehydration followed by propane refrigeration, the principal competitive technology. At the end of this demonstration project the process will be ready for commercialization. The route to commercialization will be developed during this project and may involve collaboration with other companies already servicing the natural gas processing industry.

  18. FIELD DEMONSTRATION OF A MEMBRANE PROCESS TO RECOVER HEAVY HYDROCARBONS AND TO REMOVE WATER FROM NATURAL GAS

    Energy Technology Data Exchange (ETDEWEB)

    R. Baker; R. Hofmann; K.A. Lokhandwala

    2003-02-14

    The objective of this project is to design, construct and field demonstrate a membrane system to recover natural gas liquids (NGL) and remove water from raw natural gas. An extended field test to demonstrate system performance under real-world conditions would convince industry users of the efficiency and reliability of the process. The system has been designed and fabricated by Membrane Technology and Research, Inc. (MTR) and will be installed and operated at British Petroleum (BP)-Amoco's Pascagoula, MS plant. The Gas Research Institute will partially support the field demonstration and BP-Amoco will help install the unit and provide onsite operators and utilities. The gas processed by the membrane system will meet pipeline specifications for dewpoint and Btu value and can be delivered without further treatment to the pipeline. Based on data from prior membrane module tests, the process is likely to be significantly less expensive than glycol dehydration followed by propane refrigeration, the principal competitive technology. At the end of this demonstration project the process will be ready for commercialization. The route to commercialization will be developed during this project and may involve collaboration with other companies already servicing the natural gas processing industry.

  19. Field Demonstration of a Membrane Process to Recover Heavy Hydrocarbons and to Remove Water from Natural Gas

    Energy Technology Data Exchange (ETDEWEB)

    R. Baker; T. Hofmann; K. A. Lokhandwala

    2006-09-29

    The objective of this project is to design, construct and field demonstrate a membrane system to recover natural gas liquids (NGL) and remove water from raw natural gas. An extended field test to demonstrate system performance under real-world high-pressure conditions is being conducted to convince industry users of the efficiency and reliability of the process. The system was designed and fabricated by Membrane Technology and Research, Inc. (MTR) and installed and operated at BP Amoco's Pascagoula, MS plant. The Gas Research Institute is partially supporting the field demonstration and BP-Amoco helped install the unit and provides onsite operators and utilities. The gas processed by the membrane system meets pipeline specifications for dew point and BTU value and can be delivered without further treatment to the pipeline. Based on data from prior membrane module tests, the process is likely to be significantly less expensive than glycol dehydration followed by propane refrigeration, the principal competitive technology. During the course of this project, MTR has sold 13 commercial units related to the field test technology, and by the end of this demonstration project the process will be ready for broader commercialization. A route to commercialization has been developed during this project and involves collaboration with other companies already servicing the natural gas processing industry.

  20. Field Demonstration of a Membrane Process to Recover Heavy Hydrocarbons and to Remove Water from Natural Gas

    Energy Technology Data Exchange (ETDEWEB)

    R. Baker; T. Hofmann; K. A. Lokhandwala

    2004-09-29

    The objective of this project is to design, construct and field demonstrate a membrane system to recover natural gas liquids (NGL) and remove water from raw natural gas. An extended field test to demonstrate system performance under real-world conditions would convince industry users of the efficiency and reliability of the process. The system has been designed and fabricated by Membrane Technology and Research, Inc. (MTR) and will be installed and operated at British Petroleum (BP)-Amoco's Pascagoula, MS plant. The Gas Research Institute will partially support the field demonstration and BP-Amoco will help install the unit and provide onsite operators and utilities. The gas processed by the membrane system will meet pipeline specifications for dewpoint and BTU value and can be delivered without further treatment to the pipeline. Based on data from prior membrane module tests, the process is likely to be significantly less expensive than glycol dehydration followed by propane refrigeration, the principal competitive technology. At the end of this demonstration project the process will be ready for commercialization. The route to commercialization will be developed during this project and may involve collaboration with other companies already servicing the natural gas processing industry.

  1. Field Demonstration of a Membrane Process to Recover Heavy Hydrocarbons and to Remove Water from Natural Gas

    Energy Technology Data Exchange (ETDEWEB)

    Kaaeid Lokhandwala

    2007-03-30

    The objective of this project was to design, construct and field demonstrate a membrane system to recover natural gas liquids (NGL) and remove water from raw natural gas. An extended field test to demonstrate system performance under real-world high-pressure conditions was conducted to convince industry users of the efficiency and reliability of the process. The system was designed and fabricated by Membrane Technology and Research, Inc. (MTR) and installed and operated at BP Amoco's Pascagoula, MS plant. The Gas Research Institute partially supported the field demonstration and BP-Amoco helped install the unit and provide onsite operators and utilities. The gas processed by the membrane system meets pipeline specifications for dew point and BTU value and can be delivered without further treatment to the pipeline. During the course of this project, MTR has sold thirteen commercial units related to the field test technology. Revenue generated from new business is already more than four times the research dollars invested in this process by DOE. The process is ready for broader commercialization and the expectation is to pursue the commercialization plans developed during this project, including collaboration with other companies already servicing the natural gas processing industry.

  2. Field Demonstration of a Membrane Process to Recover Heavy Hydrocarbons and to Remove Water from Natural Gas

    Energy Technology Data Exchange (ETDEWEB)

    R. Baker; T. Hofmann; K. A. Lokhandwala

    2005-09-29

    The objective of this project is to design, construct and field demonstrate a membrane system to recover natural gas liquids (NGL) and remove water from raw natural gas. An extended field test to demonstrate system performance under real-world high-pressure conditions is being conducted to convince industry users of the efficiency and reliability of the process. The system was designed and fabricated by Membrane Technology and Research, Inc. (MTR) and installed and operated at BP Amoco's Pascagoula, MS plant. The Gas Research Institute is partially supporting the field demonstration and BP-Amoco helped install the unit and provided onsite operators and utilities. The gas processed by the membrane system meets pipeline specifications for dewpoint and BTU value and can be delivered without further treatment to the pipeline. Based on data from prior membrane module tests, the process is likely to be significantly less expensive than glycol dehydration followed by propane refrigeration, the principal competitive technology. During the course of this project, MTR has sold 11 commercial units related to the field test technology, and by the end of this demonstration project the process will be ready for broader commercialization. A route to commercialization has been developed during this project and involves collaboration with other companies already servicing the natural gas processing industry.

  3. Application of Ozone and Oxygen to Reduce Chemical Oxygen Demand and Hydrogen Sulfide from a Recovered Paper Processing Plant

    Directory of Open Access Journals (Sweden)

    Patricia A. Terry

    2010-01-01

    Full Text Available A pilot study was performed at the Fox River Fiber recovered paper processing company in DePere, Wisconsin, to determine the extent to which injection of oxygen and ozone could reduce the high chemical oxygen demand, COD, in the effluent and the effectiveness of the ozone/oxygen stream in suppressing production of hydrogen sulfide gas in downstream sewage lines. Adaptive Ozone Solutions, LLC, supplied the oxygen/ozone generation and injection system. Samples were analyzed both before and after oxygen/ozone injection. Hydrogen sulfide gas was continuously monitored at sewer stations downstream of Fox River Fiber. Results showed that with a very short contact time, effluent COD was reduced by over 15%. A simple kinetic model predicts that a contact time of fewer than 30 minutes could reduce COD by as much as 60%. In addition, downstream hydrogen sulfide gas production in the sewage mains was also better controlled, such that costly Bioxide applications could be reduced.

  4. Understanding the determinants of volatility clustering in terms of stationary Markovian processes

    Science.gov (United States)

    Miccichè, S.

    2016-11-01

    Volatility is a key variable in the modeling of financial markets. The most striking feature of volatility is that it is a long-range correlated stochastic variable, i.e. its autocorrelation function decays like a power-law τ-β for large time lags. In the present work we investigate the determinants of such feature, starting from the empirical observation that the exponent β of a certain stock's volatility is a linear function of the average correlation of such stock's volatility with all other volatilities. We propose a simple approach consisting in diagonalizing the cross-correlation matrix of volatilities and investigating whether or not the diagonalized volatilities still keep some of the original volatility stylized facts. As a result, the diagonalized volatilities result to share with the original volatilities either the power-law decay of the probability density function and the power-law decay of the autocorrelation function. This would indicate that volatility clustering is already present in the diagonalized un-correlated volatilities. We therefore present a parsimonious univariate model based on a non-linear Langevin equation that well reproduces these two stylized facts of volatility. The model helps us in understanding that the main source of volatility clustering, once volatilities have been diagonalized, is that the economic forces driving volatility can be modeled in terms of a Smoluchowski potential with logarithmic tails.

  5. Process engineering versus product engineering - A case study on volatile organic compounds removal

    DEFF Research Database (Denmark)

    Coutinho, João A.P.; Vilela, T.; Pereira, P.

    2005-01-01

    to the problem-need specified in the beginning of the project, but producing a novel formulation (chemical product design) represents a method that results to a completely xylene-free process which is environmentally and economically more interesting than those generated via the more traditional process......Three solutions for removing the dangerous volatile organic compound (VOC) xylene from an industrial coating process are presented and compared. Two of them are based on classical process engineering principles, i.e., development of separation-cleaning methods such as incineration and adsorption....... The last approach is somewhat different and is based on the so-called product engineering concept, i.e., in this case, a change of the formulation so that xylene is entirely eliminated from the process. It is shown that both the process and the product engineering approaches yield viable solutions...

  6. Active thermography and post-processing image enhancement for recovering of abraded and paint-covered alphanumeric identification marks

    Science.gov (United States)

    Montanini, R.; Quattrocchi, A.; Piccolo, S. A.

    2016-09-01

    Alphanumeric marking is a common technique employed in industrial applications for identification of products. However, the realised mark can undergo deterioration, either by extensive use or voluntary deletion (e.g. removal of identification numbers of weapons or vehicles). For recovery of the lost data many destructive or non-destructive techniques have been endeavoured so far, which however present several restrictions. In this paper, active infrared thermography has been exploited for the first time in order to assess its effectiveness in restoring paint covered and abraded labels made by means of different manufacturing processes (laser, dot peen, impact, cold press and scribe). Optical excitation of the target surface has been achieved using pulse (PT), lock-in (LT) and step heating (SHT) thermography. Raw infrared images were analysed with a dedicated image processing software originally developed in Matlab™, exploiting several methods, which include thermographic signal reconstruction (TSR), guided filtering (GF), block guided filtering (BGF) and logarithmic transformation (LN). Proper image processing of the raw infrared images resulted in superior contrast and enhanced readability. In particular, for deeply abraded marks, good outcomes have been obtained by application of logarithmic transformation to raw PT images and block guided filtering to raw phase LT images. With PT and LT it was relatively easy to recover labels covered by paint, with the latter one providing better thermal contrast for all the examined targets. Step heating thermography never led to adequate label identification instead.

  7. Complex electronic waste treatment - An effective process to selectively recover copper with solutions containing different ammonium salts.

    Science.gov (United States)

    Sun, Z H I; Xiao, Y; Sietsma, J; Agterhuis, H; Yang, Y

    2016-11-01

    Recovery of valuable metals from electronic waste has been highlighted by the EU directives. The difficulties for recycling are induced by the high complexity of such waste. In this research, copper could be selectively recovered using an ammonia-based process, from industrially processed information and communication technology (ICT) waste with high complexity. A detailed understanding on the role of ammonium salt was focused during both stages of leaching copper into a solution and the subsequent step for copper recovery from the solution. By comparing the reactivity of the leaching solution with different ammonium salts, their physiochemical behaviour as well as the leaching efficiency could be identified. The copper recovery rate could reach 95% with ammonium carbonate as the leaching salt. In the stage of copper recovery from the solution, electrodeposition was introduced without an additional solvent extraction step and the electrochemical behaviour of the solution was figured out. With a careful control of the electrodeposition conditions, the current efficiency could be improved to be 80-90% depending on the ammonia salts and high purity copper (99.9wt.%). This research provides basis for improving the recyclability and efficiency of copper recovery from such electronic waste and the whole process design for copper recycling.

  8. Vapour Treatment Method Against Other Pyro- and Hydrometallurgical Processes Applied to Recover Platinum From Used Auto Catalytic Converters

    Institute of Scientific and Technical Information of China (English)

    Agnieszka FORNALCZYK; Mariola SATERNUS

    2013-01-01

    Today more and more cars are produced every year.All of them have to be equipped with catalytic converters,the main role of which is to obtain substances harmless to the environment instead of exhausted gases.Catalytic converters contain platinum group metals (PGM) especially platinum,palladium and rhodium.The price of these metals and their increasing demand are the reasons why today it is necessary to recycle used auto catalytic converters.There are many available methods of recovering PGM metals from them,especially platinum.These methods used mainly hydrometallurgical processes; however pyrometallurgical ones become more and more popular.The article presents results of the research mainly concerning pyrometallurgical processes.Two groups of research were carried out.In the first one different metals such as lead,magnesium and copper were used as a metal collector.During the tests,platinum went to those metals forming an alloy.In other research metal vapours were blown through catalytic converter carrier (grinded or whole).In the tests metals such as calcium,magnesium,cadmium and zinc were applied.As a result white or grey powder (metal plus platinum) was obtained.The tables present results of the research.Processing parameters and conclusions are also shown.To compare efficiency of pyrometallurgical and hydrometallurgical methods catalytic converter carrier and samples of copper with platinum obtained from pyrometallurgical method were solved in aqua regia,mixture of aqua regia and fluoric acid.

  9. FIELD DEMONSTRATION OF A MEMBRANE PROCESS TO RECOVER HEAVY HYDROCARBONS AND TO REMOVE WATER FROM NATURAL GAS

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2002-04-10

    The objective of this project is to design, construct and field demonstrate a 3-MMscfd membrane system to recover natural gas liquids (NGL) and remove water from raw natural gas. The gas processed by the membrane system will meet pipeline specifications for dew point and Btu value, and the process is likely to be significantly less expensive than glycol dehydration followed by propane refrigeration, the principal competitive technology. The BP-Amoco gas processing plant in Pascagoula, MS was finalized as the location for the field demonstration. Detailed drawings of the MTR membrane skid (already constructed) were submitted to the plant in February, 2000. However, problems in reaching an agreement on the specifications of the system compressor delayed the project significantly, so MTR requested (and was subsequently granted) a no-cost extension to the project. Following resolution of the compressor issues, the goal is to order the compressor during the first quarter of 2002, and to start field tests in mid-2002. Information from potential users of the membrane separation process in the natural gas processing industry suggests that applications such as fuel gas conditioning and wellhead gas processing are the most promising initial targets. Therefore, most of our commercialization effort is focused on promoting these applications. Requests for stream evaluations and for design and price quotations have been received through MTR's web site, from direct contact with potential users, and through announcements in industry publications. To date, about 90 commercial quotes have been supplied, and orders totaling about $1.13 million for equipment or rental of membrane units have been received.

  10. Effects of high hydrostatic pressure and thermal processing on bioactive compounds, antioxidant activity, and volatile profile of mulberry juice.

    Science.gov (United States)

    Wang, Fan; Du, Bao-Lei; Cui, Zheng-Wei; Xu, Li-Ping; Li, Chun-Yang

    2017-03-01

    The aim of this study was to investigate the effects of high hydrostatic pressure and thermal processing on microbiological quality, bioactive compounds, antioxidant activity, and volatile profile of mulberry juice. High hydrostatic pressure processing at 500 MPa for 10 min reduced the total viable count from 4.38 log cfu/ml to nondetectable level and completely inactivated yeasts and molds in raw mulberry juice, ensuring the microbiological safety as thermal processing at 85 ℃ for 15 min. High hydrostatic pressure processing maintained significantly (p juice than thermal processing. The main volatile compounds of mulberry juice were aldehydes, alcohols, and ketones. High hydrostatic pressure processing enhanced the volatile compound concentrations of mulberry juice while thermal processing reduced them in comparison with the control. These results suggested that high hydrostatic pressure processing could be an alternative to conventional thermal processing for production of high-quality mulberry juice.

  11. Toward energy-neutral wastewater treatment: a high-rate contact stabilization process to maximally recover sewage organics.

    Science.gov (United States)

    Meerburg, Francis A; Boon, Nico; Van Winckel, Tim; Vercamer, Jensen A R; Nopens, Ingmar; Vlaeminck, Siegfried E

    2015-03-01

    The conventional activated sludge process is widely used for wastewater treatment, but to progress toward energy self-sufficiency, the wastewater treatment scheme needs to radically improve energy balances. We developed a high-rate contact stabilization (HiCS) reactor system at high sludge-specific loading rates (>2 kg bCOD kg(-1)TSS d(-1)) and low sludge retention times (organics than high-rate conventional activated sludge (HiCAS) and the low-rate variants of HiCS and HiCAS. The best HiCS system recovered 36% of the influent chemical energy as methane, due to the combined effects of low production of CO2, high sludge yield, and high methane yield of the produced sludge. The HiCS system imposed a feast-famine cycle and a putative selection pressure on the sludge micro-organisms toward substrate adsorption and storage. Given further optimization, it is a promising process for energy recovery from wastewater.

  12. Bio-electrolytic sensor for rapid monitoring of volatile fatty acids in anaerobic digestion process

    DEFF Research Database (Denmark)

    Jin, Xiangdan; Li, Xiaohu; Zhao, Nannan;

    2017-01-01

    This study presents an innovative biosensor that was developed on the basis of a microbial electrolysis cell for fast and reliable measurement of volatile fatty acids (VFA) during anaerobic digestion (AD) process. The bio-electrolytic sensor was first tested with synthetic wastewater containing...... to monitor VFA concentrations in a lab-scale AD reactor for a month. The VFA measurements from the sensor correlated well with those from GC analysis which proved the accuracy of the system. Since hydrogen was produced in the cathode as byproduct during monitoring, the system could be energy self...

  13. Field Demonstration of a Membrane Process to Recover Heavy Hydrocarbons and to Remove Water from Natural Gas

    Energy Technology Data Exchange (ETDEWEB)

    Kaaeid Lokhandwala

    2003-09-29

    The objective of this project is to design, construct and field demonstrate a membrane system to recover natural gas liquids (NGLs) and remove water from raw natural gas. To convince industry users of the efficiency and reliability of the process, we plan to conduct an extended field test to demonstrate system performance under real-world conditions. The membrane system has been designed and fabricated by Membrane Technology and Research, Inc. (MTR). The MTR membrane system and the compressor are now onsite at BP's Pascagoula, MS plant. The plant is undergoing a very significant expansion and the installation of the membrane unit into the test location is being implemented, albeit at a slower rate than we expected. The startup of the system and conducting of tests will occur in the next six months, depending on the availability of the remaining budget. In the interim, significant commercial progress has been made regarding the introduction of the NGL membrane and systems into the natural gas market.

  14. Evolution process and sources of ambient volatile organic compounds during a severe haze event in Beijing, China.

    Science.gov (United States)

    Wu, Rongrong; Li, Jing; Hao, Yufang; Li, Yaqi; Zeng, Limin; Xie, Shaodong

    2016-08-01

    108 ambient volatile organic compounds (VOCs) were measured continuously at a time resolution of an hour using an online gas chromatography-frame ionization detector/mass spectrometry (GC-FID/MS) in October 2014 in Beijing, and positive matrix factorization (PMF) was performed with online data. The evolution process and causes for high levels of VOCs during a haze event were investigated through comprehensive analysis. Results show that mixing ratios of VOCs during the haze event (89.29 ppbv) were 2 to 5 times as that in non-haze days, There was a distinct accumulation process of VOCs at the beginning of the haze event, and the mixing ratios of VOCs maintained at the high levels until to the end of pollution when the mixing ratios of ambient VOCs recovered to the normal concentration levels in a few hours. Some reactive and toxic species increased remarkably as well, which indicates a potential health risk to the public in terms of VOCs. Eight sources were resolved by PMF, and results revealed gasoline exhaust was the largest contributor (32-46%) to the ambient VOCs in Beijing. Emissions of gasoline exhaust surged from 13.46 to 40.36 ppbv, with a similar variation pattern to total VOCs, indicating that high levels of VOCs were largely driven to by expanded vehicular emissions. Emissions of biomass burning also increased noticeably (from 2.32 to 11.12 ppbv), and backward trajectories analysis indicated regional transport of biomass burning emissions. Our findings suggested that extremely high levels of VOCs during the haze event was primarily attributed to vehicular emissions, biomass burning and regional transport, as well as stationary synoptic conditions.

  15. Optimization of process parameters for production of volatile fatty acid, biohydrogen and methane from anaerobic digestion.

    Science.gov (United States)

    Khan, M A; Ngo, H H; Guo, W S; Liu, Y; Nghiem, L D; Hai, F I; Deng, L J; Wang, J; Wu, Y

    2016-11-01

    The anaerobic digestion process has been primarily utilized for methane containing biogas production over the past few years. However, the digestion process could also be optimized for producing volatile fatty acids (VFAs) and biohydrogen. This is the first review article that combines the optimization approaches for all three possible products from the anaerobic digestion. In this review study, the types and configurations of the bioreactor are discussed for each type of product. This is followed by a review on optimization of common process parameters (e.g. temperature, pH, retention time and organic loading rate) separately for the production of VFA, biohydrogen and methane. This review also includes additional parameters, treatment methods or special additives that wield a significant and positive effect on production rate and these products' yield.

  16. Markov switching in GARCH processes and mean reverting stock market volatility

    OpenAIRE

    Dueker, Michael J.

    1995-01-01

    This paper introduces four models of conditional heteroskedasticity that contain markov switching parameters to examine their multi-period stock-market volatility forecasts as predictions of options-implied volatilities. The volatility model that best predicts the behavior of the optionsimplied volatilities allows the student-t degrees-of-freedom parameter to switch such that the conditional variance and kurtosis are subject to discrete shifts. The half-life of the most leptokurtic state is e...

  17. Influence of processing on the volatile profile of strawberry spreads made with isomaltulose.

    Science.gov (United States)

    Peinado, I; Rosa, E; Heredia, A; Escriche, I; Andrés, A

    2013-05-01

    A new strawberry spread formulated with fructose and isomaltulose (replacing sucrose partially or totally) and a high percentage of fruit was developed in line with the new trend of healthier products. This work studies the influence of some process variables (percentage of sugar, pectin and citric acid, and time of thermal treatment) on the volatile profile of these spreads with different formulations. The ripeness of the raw strawberries influences the concentrations of some of the compounds in the spreads, such as isobutyl acetate, butyl butyrate, 3-hexen-1-yl acetate or propan-2-ol. The process conditions have an important effect on the volatile profiles. Most of the esters and alcohols decreased whereas 13 new compounds appear, mostly furans (furfural, 2-acetylfurane, 5-methyl furfural, mesifurane) and aldehydes (octanal, nonanal, decanal and benzaldeyhde). In general, the spreads formulated with sucrose-isomaltulose that contained higher levels of pectin and citric acid gave better results in the preservation of the original aromatic compounds in raw strawberries. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Generalized Fractional Processes with Long Memory and Time Dependent Volatility Revisited

    Directory of Open Access Journals (Sweden)

    M. Shelton Peiris

    2016-09-01

    Full Text Available In recent years, fractionally-differenced processes have received a great deal of attention due to their flexibility in financial applications with long-memory. This paper revisits the class of generalized fractionally-differenced processes generated by Gegenbauer polynomials and the ARMA structure (GARMA with both the long-memory and time-dependent innovation variance. We establish the existence and uniqueness of second-order solutions. We also extend this family with innovations to follow GARCH and stochastic volatility (SV. Under certain regularity conditions, we give asymptotic results for the approximate maximum likelihood estimator for the GARMA-GARCH model. We discuss a Monte Carlo likelihood method for the GARMA-SV model and investigate finite sample properties via Monte Carlo experiments. Finally, we illustrate the usefulness of this approach using monthly inflation rates for France, Japan and the United States.

  19. The lived experiences of aboriginal adolescent survivors of childhood cancer during the recovering process in Taiwan: A descriptive qualitative research.

    Science.gov (United States)

    Cheng, Ya-Chun; Huang, Chu-Yu; Wu, Wei-Wen; Chang, Shu-Chuan; Lee-Hsieh, Jane; Liang, Shu-Yuan; Cheng, Su-Fen

    2016-06-01

    The purpose of this study was to understand the experiences of Taiwanese aboriginal adolescent survivors of childhood cancer during the process of recovery. A snowball sampling strategy was used to recruit participants from the pediatrics unit of a medical center in the eastern region of Taiwan. In-depth interviews were conducted with 11 aboriginal adolescent childhood cancer survivors. The data were analyzed using content analysis. The results revealed three major themes with subthemes within each theme. The three major themes are: roots of resilience, transformation and growth, and meaning of traditional rituals for resilience. The three subthemes within "roots of resilience" include: "feeling secure through company of family, care and financial support", "receiving support from the important others and religion" and "learning to self-adjust". The three subthemes revealed within "transformation and growth" are: restructuring the relationship with peers, "appreciating parents' hard work", and "learning to seize the moment". The two subthemes within "meaning of traditional rituals to resilience" include: "feeling blessed with the power of ancestral spirits" and "strengthening ethnic identity". This study provided insight into the experiences of aboriginal adolescents as they recovered from childhood cancer. The experiences made positive impacts by inspiring growth in maturity and consolidating aboriginal ethnic identity. The adolescents were empowered by support from family, friends and clansmen, and by their participation in aboriginal rituals. As healthcare professionals care for the aboriginal adolescents, it is critical to consider this culturally and ethnically specific knowledge/experience of surviving cancer to improve quality of care. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Observed glacier and volatile distribution on Pluto from atmosphere-topography processes.

    Science.gov (United States)

    Bertrand, Tanguy; Forget, François

    2016-12-01

    Pluto has a variety of surface frosts and landforms as well as a complex atmosphere. There is ongoing geological activity related to the massive Sputnik Planitia glacier, mostly made of nitrogen (N2) ice mixed with solid carbon monoxide and methane, covering the 4-kilometre-deep, 1,000-kilometre-wide basin of Sputnik Planitia near the anti-Charon point. The glacier has been suggested to arise from a source region connected to the deep interior, or from a sink collecting the volatiles released planetwide. Thin deposits of N2 frost, however, were also detected at mid-northern latitudes and methane ice was observed to cover most of Pluto except for the darker, frost-free equatorial regions. Here we report numerical simulations of the evolution of N2, methane and carbon monoxide on Pluto over thousands of years. The model predicts N2 ice accumulation in the deepest low-latitude basin and the threefold increase in atmospheric pressure that has been observed to occur since 1988. This points to atmospheric-topographic processes as the origin of Sputnik Planitia's N2 glacier. The same simulations also reproduce the observed quantities of volatiles in the atmosphere and show frosts of methane, and sometimes N2, that seasonally cover the mid- and high latitudes, explaining the bright northern polar cap reported in the 1990s and the observed ice distribution in 2015. The model also predicts that most of these seasonal frosts should disappear in the next decade.

  1. Observed glacier and volatile distribution on Pluto from atmosphere-topography processes

    Science.gov (United States)

    Bertrand, Tanguy; Forget, François

    2016-12-01

    Pluto has a variety of surface frosts and landforms as well as a complex atmosphere. There is ongoing geological activity related to the massive Sputnik Planitia glacier, mostly made of nitrogen (N2) ice mixed with solid carbon monoxide and methane, covering the 4-kilometre-deep, 1,000-kilometre-wide basin of Sputnik Planitia near the anti-Charon point. The glacier has been suggested to arise from a source region connected to the deep interior, or from a sink collecting the volatiles released planetwide. Thin deposits of N2 frost, however, were also detected at mid-northern latitudes and methane ice was observed to cover most of Pluto except for the darker, frost-free equatorial regions. Here we report numerical simulations of the evolution of N2, methane and carbon monoxide on Pluto over thousands of years. The model predicts N2 ice accumulation in the deepest low-latitude basin and the threefold increase in atmospheric pressure that has been observed to occur since 1988. This points to atmospheric-topographic processes as the origin of Sputnik Planitia’s N2 glacier. The same simulations also reproduce the observed quantities of volatiles in the atmosphere and show frosts of methane, and sometimes N2, that seasonally cover the mid- and high latitudes, explaining the bright northern polar cap reported in the 1990s and the observed ice distribution in 2015. The model also predicts that most of these seasonal frosts should disappear in the next decade.

  2. Effect of high pressure high temperature processing on the volatile fraction of differently coloured carrots.

    Science.gov (United States)

    Kebede, Biniam T; Grauwet, Tara; Palmers, Stijn; Vervoort, Liesbeth; Carle, Reinhold; Hendrickx, Marc; Van Loey, Ann

    2014-06-15

    To get deeper insight into the effect of high pressure high temperature (HPHT) processing on the volatile fraction of carrots, differently coloured cultivars exhibiting orange, purple, red and yellow hues were investigated. The impact of HPHT sterilisation was compared with thermal sterilisation based on equivalent microbiological inactivation. The results of this study demonstrated HPHT sterilisation to exert a distinct effect on important chemical reactions in comparison to thermal sterilisation. A comprehensive integration of MS-based metabolomic fingerprinting (HS-SPME-GC-MS) and chemometric tools has been implemented as an untargeted multivariate screening tool to identify differences. In all carrot cultivars, two dominant discriminative quality-related reactions were found: oxidative degradation and the Maillard reaction. Regarding the first reaction, oxidative terpenes, free fatty acids and carotenoids degradation products were detected at higher levels after HPHT sterilisation. Regarding the latter reaction, HPHT sterilisation appeared to suppress the formation of Maillard and Strecker degradation products.

  3. Amino acid, fatty acid, and mineral profiles of materials recovered from rainbow trout (Oncorhynchus mykiss) processing by-products using isoelectric solubilization/precipitation.

    Science.gov (United States)

    Chen, Y-C; Tou, J C; Jaczynski, J

    2007-11-01

    Protein, lipid, and insolubles (bones, skin, scales, fins, insoluble protein, and more) were recovered from rainbow trout processing by-products by means of isoelectric solubilization/precipitation at basic pH and acidic pH. Isoelectric solubilization/precipitation of the trout processing by-products resulted in the recovery of protein that was higher (P processing by-products. Basic pH treatments yielded a higher (P processing by-products, indicating that the pH treatments had no effect on these FAs. Ca and P contents of the processing by-products exceeded the recommended dietary allowances (RDA), but Fe and Mg did not. Basic pH treatments yielded protein with the lowest (P minerals and the highest (P processing by-products effectively removed minerals from the recovered protein without removal of the bones, skin, scales, fins, and so on, prior to processing. The results indicated that isoelectric solubilization/precipitation, particularly at basic pH, permitted recovery of high-quality protein and lipids from fish processing by-products for human food uses; also, the recovered insolubles may be used in animal feeds as a source of minerals.

  4. Effects of volatile fatty acids on a thermophilic anaerobic hydrogen fermentation process degrading peptone.

    Science.gov (United States)

    Cheng, S S; Chang, S M; Chen, S T

    2002-01-01

    Hydrogen fermentation using glucose as a single substrate caused abrupt pH drops and the gradual losses of hydrogen producers, which in turn led to system failure. In this study the use of a proteinaceous substrate, peptone, avoided the abrupt pH drops in the reactive system and allowed for further exploration of volatile fatty acids (VFAs) and pH effects on the hydrogen fermentation process. Our results showed that: (1) during the hydrogen fermentation tests, the abrupt pH drops were avoided thus system stability increased due to the production of ammonia from the peptone fermented, (2) pH control was not necessary and the addition of acetate to the process had little effect on the hydrogen fermentation process, (3) at the extreme pHs the addition of acetate either lengthened the lag phase (pH hydrogen production rate (pH > or = 8), and both situations were not desired, and (4) high VFA content in the system sped up the consumption of hydrogen gas. Results of this study suggested that the hydrogen fermentation using the protein-containing substances as substrate was beneficial in maintaining the system pH. As long as the pH was maintained around 6-8, system inhibition due to VFAs accumulation was minimized. Thus, the optimal operation of a hydrogen fermentation process would be achievable via the control of substrate composition at a certain carbohydrate-to-protein ratio.

  5. Differential volatile signatures from skin, naevi and melanoma: a novel approach to detect a pathological process.

    Directory of Open Access Journals (Sweden)

    Tatjana Abaffy

    Full Text Available BACKGROUND: Early detection of melanoma is of great importance to reduce mortality. Discovering new melanoma biomarkers would improve early detection and diagnosis. Here, we present a novel approach to detect volatile compounds from skin. METHODS AND FINDINGS: We used Head Space Solid Phase Micro-Extraction (HS-SPME and gas chromatography/mass spectrometry (GC/MS to identify volatile signatures from melanoma, naevi and skin samples. We hypothesized that the metabolic state of tissue alters the profile of volatile compounds. Volatiles released from fresh biopsy tissue of melanoma and benign naevus were compared based on their difference in frequency distribution and their expression level. We also analyzed volatile profiles from frozen tissue, including skin and melanoma. CONCLUSIONS: Three volatiles, 4-methyl decane, dodecane and undecane were preferentially expressed in both fresh and frozen melanoma, indicating that they are candidate biomarkers. Twelve candidate biomarkers evaluated by fuzzy logic analysis of frozen samples distinguished melanoma from skin with 89% sensitivity and 90% specificity. Our results demonstrate proof-of-principle that there is differential expression of volatiles in melanoma. Our volatile metabolomic approach will lead to a better understanding of melanoma and can enable development of new diagnostic and treatment strategies based on altered metabolism.

  6. [Occurrence and distribution of volatile organic compounds in conventional and advanced drinking water treatment processes].

    Science.gov (United States)

    Chen, Xi-Chao; Luo, Qian; Chen, Hu; Wei, Zi; Wang, Zi-Jian; Xu, Ke-Wen

    2013-12-01

    A series of experiments were conducted to study the occurrence and distribution of volatile organic compounds (VOCs) in conventional and advanced drinking water treatment processes of 3 water treatment plants in Lianyungang City. Results showed that 30 compounds of 3 classes were detected from 67 kinds of VOCs in all the samples collected. The concentrations of carbonyl compounds, halogenated hydrocarbons and benzenes detected were in the ranges of 0.04-61.27, 0.02-35.61 and 0.07-2.33 microg x L(-1) respectively. Comparing the changes of different VOCs in three drinking water treatment plants, conventional chlorination process could effectively remove benzenes but meanwhile produced trihalomethanes (THMs). Additional advanced treatment ozonation-biological activated carbon process could decrease the formation of THMs during pre-chlorination but produced new risky contaminants like carbonyl compounds. The changes of VOCs in tap water were also investigated. It was found that carbonyl compounds produced by ozonation could be further transformed to THMs with residual chlorine. However, the health risks of all detected compounds in tap water were at a low level, except that the carcinogenic risk of crotonaldehydes (9.3 x 10(-5)-2.2 x 10(-4)) was slightly higher than the US EPA threshold (10(-6)-10(-4)).

  7. Exposure to Volatile Organic Compounds and Possibility of Exposure to By-product Volatile Organic Compounds in Photolithography Processes in Semiconductor Manufacturing Factories.

    Science.gov (United States)

    Park, Seung-Hyun; Shin, Jung-Ah; Park, Hyun-Hee; Yi, Gwang Yong; Chung, Kwang-Jae; Park, Hae-Dong; Kim, Kab-Bae; Lee, In-Seop

    2011-09-01

    The purpose of this study was to measure the concentration of volatile organic compound (VOC)s originated from the chemicals used and/or derived from the original parental chemicals in the photolithography processes of semiconductor manufacturing factories. A total of four photolithography processes in 4 Fabs at three different semiconductor manufacturing factories in Korea were selected for this study. This study investigated the types of chemicals used and generated during the photolithography process of each Fab, and the concentration levels of VOCs for each Fab. A variety of organic compounds such as ketone, alcohol, and acetate compounds as well as aromatic compounds were used as solvents and developing agents in the processes. Also, the generation of by-products, such as toluene and phenol, was identified through a thermal decomposition experiment performed on a photoresist. The VOC concentration levels in the processes were lower than 5% of the threshold limit value (TLV)s. However, the air contaminated with chemical substances generated during the processes was re-circulated through the ventilation system, thereby affecting the airborne VOC concentrations in the photolithography processes. Tens of organic compounds were being used in the photolithography processes, though the types of chemical used varied with the factory. Also, by-products, such as aromatic compounds, could be generated during photoresist patterning by exposure to light. Although the airborne VOC concentrations resulting from the processes were lower than 5% of the TLVs, employees still could be exposed directly or indirectly to various types of VOCs.

  8. Pricing of American Put Option under a Jump Diffusion Process with Stochastic Volatility in an Incomplete Market

    Directory of Open Access Journals (Sweden)

    Shuang Li

    2014-01-01

    Full Text Available We study the pricing of American options in an incomplete market in which the dynamics of the underlying risky asset is driven by a jump diffusion process with stochastic volatility. By employing a risk-minimization criterion, we obtain the Radon-Nikodym derivative for the minimal martingale measure and consequently a linear complementarity problem (LCP for American option price. An iterative method is then established to solve the LCP problem for American put option price. Our numerical results show that the model and numerical scheme are robust in capturing the feature of incomplete finance market, particularly the influence of market volatility on the price of American options.

  9. Improved process model for ammonia volatilization from anaerobic swine lagoons under varying wind speeds and gas bubbling

    Science.gov (United States)

    Ammonia volatilization from treatment lagoons varies widely with the lagoon water total ammonia concentration, pH, temperature, suspended solids, atmospheric ammonia concentration above the water surface, and wind speed. Ammonia emissions were estimated with a process-based mechanistic model using a...

  10. New technology for volatile components stripping in process fluids; Nova tecnologia para estripagem de componentes volateis em fluidos de processo

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Roberto Massao [White Martins Gases Industriais, Rio de Janeiro, RJ (Brazil)

    1992-12-31

    Stripping is a process used in order to remove volatile contaminants during the purification step by bubbling inert gas in a contaminated liquid. This work defines the stripping process and its process parameters, describes some stripping techniques and introduces the supersonic stripper, that works at supersonic velocity. Dissolved oxygen reduction and stripping time reduction results are shown. The conclusion is that the supersonic stripper is superior to the in-line conventional systems. (author) 6 refs., 2 figs.

  11. Determination of volatile and non-volatile products of milk fermentation processes using capillary zone electrophoresis and solid phase microextraction coupled to gas chromatography.

    Science.gov (United States)

    Ligor, Magdalena; Jarmalaviciene, Reda; Szumski, Michal; Maruska, Audrius; Buszewski, Boguslaw

    2008-08-01

    The aim of the investigations was to develop analytical methods for the determination of selected volatile and non-volatile organic compounds numbering among the final products of milk fermentation. The analyzed compounds were as follows: biacetyl and carboxylic acids (formic, acetic, citric, and lactic). The model yogurt was prepared under controlled conditions in our laboratory by addition of the selected bacteria (Lactobacillus bulgaricus and Streptococcus thermophilus) to the milk sample. The temperature, time, and stirring were controlled during the fermentation process. Factors considered in SPMPE-GC-FID method development included fiber exposure time, salt addition, temperature of extraction, and temperature of desorption. Various SPME fibers, for example with PDMS, CAR/PDMS, PA, and PDMS/DVB coatings, were tested to obtain the highest recovery of the investigated compounds extracted from yogurt samples. Based on these preliminary experiments, qualitative and quantitative analyses for the determination of biacetyl were performed by SPME-GC-FID. Moreover, a capillary zone electrophoresis method was developed for the determination of carboxylic acids in the yogurt samples. The buffer composition as well as deproteinization by acetonitrile were found to have a crucial effect on the analysis.

  12. [Emission characteristics and safety evaluation of volatile organic compounds in manufacturing processes of automotive coatings].

    Science.gov (United States)

    Zeng, Pei-Yuan; Li, Jian-Jun; Liao, Dong-Qi; Tu, Xiang; Xu, Mei-Ying; Sun, Guo-Ping

    2013-12-01

    Emission characteristics of volatile organic compounds (VOCs) were investigated in an automotive coating manufacturing enterprise. Air samples were taken from eight different manufacturing areas in three workshops, and the species of VOCs and their concentrations were measured by gas chromatography-mass spectrometry (GC-MS). Safety evaluation was also conducted by comparing the concentration of VOCs with the permissible concentration-short term exposure limit (PC-STEL) regulated by the Ministry of Health. The results showed that fifteen VOCs were detected in the indoor air of the automotive coatings workshop, including benzene, toluene, ethylbenzene, xylene, ethyl acetate, butyl acetate, methyl isobutyl ketone, propylene glycol monomethyl ether acetate, trimethylbenzene and ethylene glycol monobutyl ether, Their concentrations widely ranged from 0.51 to 593.14 mg x m(-3). The concentrations of TVOCs were significantly different among different manufacturing processes. Even in the same manufacturing process, the concentrations of each component measured at different times were also greatly different. The predominant VOCs of indoor air in the workshop were identified to be ethylbenzene and butyl acetate. The concentrations of most VOCs exceeded the occupational exposure limits, so the corresponding control measures should be taken to protect the health of the workers.

  13. Chemical fractionation and speciation modelling for optimization of ion-exchange processes to recover palladium from industrial wastewater.

    Science.gov (United States)

    Folens, K; Van Hulle, S; Vanhaecke, F; Du Laing, G

    2016-01-01

    Palladium is used in several industrial applications and, given its high intrinsic value, intense efforts are made to recover the element. In this hydrometallurgic perspective, ion-exchange (IEX) technologies are principal means. Yet, without incorporating the chemical and physical properties of the Pd present in real, plant-specific conditions, the recovery cannot reach its technical nor economic optimum. This study characterized a relevant Pd-containing waste stream of a mirror manufacturer to provide input for a speciation model, predicting the Pd speciation as a function of pH and chloride concentration. Besides the administered neutral PdCl2 form, both positively and negatively charged [PdCln](2-n) species occur depending on the chloride concentration in solution. Purolite C100 and Relite 2AS IEX resins were selected and applied in combination with other treatment steps to optimize the Pd recovery. A combination of the cation and anion exchange resins was found successful to quantitatively recover Pd. Given the fact that Pd was also primarily associated with particles, laboratory-scale experiments focused on physical removal of the Pd-containing flow were conducted, which showed that particle-bound Pd can already be removed by physical pre-treatment prior to IEX, while the ionic fraction remains fully susceptible to the IEX mechanism.

  14. Simultaneous determination of volatile and non-volatile nitrosamines in processed meat products by liquid chromatography tandem mass spectrometry using atmospheric pressure chemical ionisation and electrospray ionisation.

    Science.gov (United States)

    Herrmann, S S; Duedahl-Olesen, L; Granby, K

    2014-02-21

    A sensitive, selective and generic method has been developed for the simultaneous determination of the contents (μgkg(-1) range) of both volatile nitrosamines (VNA) and non-volatile nitrosamines (NVNA) in processed meat products. The extraction procedure only requires basic laboratory equipment and a small volume of organic solvent. Separation and quantification were performed by the developed LC-(APCI/ESI)MS/MS method. The method was validated using spiked samples of three different processed meat products. Satisfactory recoveries (50-130%) and precisions (2-23%) were obtained for eight VNA and six NVNAs with LODs generally between 0.2 and 1μgkg(-1), though for a few analyte/matrix combinations higher LODs were obtained (3 to 18μgkg(-1)). The validation results show that results obtained for one meat product is not always valid for other meat products. We were not able to obtain satisfactory results for N-nitrosohydroxyproline (NHPRO), N-nitrosodibenzylamine (NDBzA) and N-nitrosodiphenylamine (NDPhA). Application of the APCI interface improved the sensitivity of the method, because of less matrix interference, and gave the method a wider scope, as some NAs were ionisable only by APCI. However, it was only possible to ionize N-nitroso-thiazolidine-4-carboxylic acid (NTCA) and N-nitroso-2-methyl-thiazolidine-4-carboxylic acid (NMTCA) by ESI. The validated method was applied for the analysis of processed meat products and contents of N-nitrosodimethylamine (NDMA), N-nitrosopyrrolidine (NPYR), N-nitrosomethylaniline (NMA), N-nitrosoproline (NPRO), NTCA, and NMTCA were found in one or several nitrite cured meat products, whereas none were detected in non-nitrite cured bacon.

  15. Implications of internal processes in the interpretation of Titan's volatile inventory measured by Cassini-Huygens

    Science.gov (United States)

    Tobie, Gabriel; Gautier, D.; Hersant, F.; Lunine, J. I.

    2010-04-01

    Based on a series of data collected by Cassini-Huygens, we constrain the composition of the primordial bricks that formed Titan and quantify the chemical exchanges that occurred on Titan between the interior and the atmosphere since its accretion. Assuming that the bricks that formed Titan had a composition close to that of Enceladus and that of the planetesimals in the feeding zone of Saturn, we show that accretional melting generate an CH4-CO2-H2S - dominated atmosphere of more than 10 bars in equilibrium with a water ocean. The partial atmospheric pressure of ammonia remains low (ammonia into nitrogen is possible just after accretion but requires the water ocean remains in contact with the atmosphere during at least 10-50 millions of years. We show that most of the gas species, except N2 and 36Ar, released during accretion are likely to be re-incorporated in the interior during the post-accretional cooling phase, owing to efficient clathration at the water/ocean interface. During this process, xenon is predicted to be almost entirely removed from the primitive atmosphere and to be stored in the form of clathrate hydrate in the interior. The composition of gases released during the rest of the evolution is determined by the stability of each gas species relative to the clathrate phase and is expected to be dominated by CH4 and CO2, and to contain small amounts of argon and CO. It can be anticipated from our analysis that flows and deposits of CO2-rich materials would be associated to cryovolcanic events. Although the detection of 40Ar clearly support that interaction with the silicate phase has occurred during Titan's history, it is still unclear if significant chemical exchanges has occurred with the rocky core. Only detection of 38Ar and of the other noble gas isotopes by a future mission will permit to determine how the silicate phase has contributed to the volatile budget of Titan. Isotopic ratios in the surface materials (H2O, CO2 ice, organic matters, gas

  16. Oxidation of diesel-generated volatile organic compounds in the selective catalytic reduction process

    Energy Technology Data Exchange (ETDEWEB)

    Koebel, M.; Elsener, M. [Paul Scherrer Inst., Villigen (Switzerland). Combustion Research

    1998-10-01

    The main part of the VOCs (volatile organic compounds) contained in diesel exhaust ({approx}80%) is oxidized to CO and CO{sub 2} over an SCR (selective catalytic reduction) catalyst. CO is the major product of this oxidation, representing about 50--70% of the formed products (CO + CO{sub 2}). This preferential formation of CO leads to a pronounced increase of CO emissions when an SCR process is added to a diesel engine. A small fraction of the VOCs is selectively oxidized to carboxylic acids over the SCR catalyst. This selectivity is due to the acidic properties of the catalyst causing the preferential desorption at the oxidation state of the acid. The main products of these oxidation reactions are the lower monocarboxylic acids and some dicarboxylic acids forming stable anhydrides, especially maleic and phthalic acid. The highest emissions of these acids are found at low temperatures; they decrease at higher temperatures. Formic acid is preferentially decomposed into carbon monoxide and water. It must therefore be assumed that the strong increase of CO mentioned above is due to a mechanism involving the thermal decomposition of formic acid formed from various primary VOCs.

  17. Coupled interactions between volatile activity and Fe oxidation state during arc crustal processes

    Science.gov (United States)

    Humphreys, Madeleine C.S.; Brooker, R; Fraser, D.C.; Burgisser, A; Mangan, Margaret T.; McCammon, C

    2015-01-01

    Arc magmas erupted at the Earth’s surface are commonly more oxidized than those produced at mid-ocean ridges. Possible explanations for this high oxidation state are that the transfer of fluids during the subduction process results in direct oxidation of the sub-arc mantle wedge, or that oxidation is caused by the effect of later crustal processes, including protracted fractionation and degassing of volatile-rich magmas. This study sets out to investigate the effect of disequilibrium crustal processes that may involve coupled changes in H2O content and Fe oxidation state, by examining the degassing and hydration of sulphur-free rhyolites. We show that experimentally hydrated melts record strong increases in Fe3+/∑Fe with increasing H2O concentration as a result of changes in water activity. This is relevant for the passage of H2O-undersaturated melts from the deep crust towards shallow crustal storage regions, and raises the possibility that vertical variations in fO2 might develop within arc crust. Conversely, degassing experiments produce an increase in Fe3+/∑Fe with decreasing H2O concentration. In this case the oxidation is explained by loss of H2 as well as H2O into bubbles during decompression, consistent with thermodynamic modelling, and is relevant for magmas undergoing shallow degassing en route to the surface. We discuss these results in the context of the possible controls on fO2 during the generation, storage and ascent of magmas in arc settings, in particular considering the timescales of equilibration relative to observation as this affects the quality of the petrological record of magmatic fO2.

  18. Polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) mitigation in the pyrolysis process of waste tires using CO₂ as a reaction medium.

    Science.gov (United States)

    Kwon, Eilhann E; Oh, Jeong-Ik; Kim, Ki-Hyun

    2015-09-01

    Our work reported the CO2-assisted mitigation of PAHs and VOCs in the thermo-chemical process (i.e., pyrolysis). To investigate the pyrolysis of used tires to recover energy and chemical products, the experiments were conducted using a laboratory-scale batch-type reactor. In particular, to examine the influence of the CO2 in pyrolysis of a tire, the pyrolytic products including C1-5-hydrocarbons (HCs), volatile organic carbons (VOCs), and polycyclic aromatic hydrocarbons (PAHs) were evaluated qualitatively by gas chromatography (GC) with mass spectroscopy (MS) as well as with a thermal conductivity detector (TCD). The mass balance of the pyrolytic products under various pyrolytic conditions was established on the basis of their weight fractions of the pyrolytic products. Our experimental work experimentally validated that the amount of gaseous pyrolytic products increased when using CO2 as a pyrolysis medium, while substantially altering the production of pyrolytic oil in absolute content (7.3-17.2%) and in relative composition (including PAHs and VOCs). Thus, the co-feeding of CO2 in the pyrolysis process can be considered an environmentally benign and energy efficient process.

  19. Influence of partial replacement of NaCl with KCl on profiles of volatile compounds in dry-cured bacon during processing

    Science.gov (United States)

    This study investigated the influence of partial substitution of NaCl with KCl on the formation of volatile compounds in bacons during processing using a purge and trap dynamic headspace GC/MS system. Three substitutions were 0% KCl (I), 40% KCl (II), and 70% KCl (III). The profiles of the volatile ...

  20. Nitrogen compounds in must and volatile profile of white wine: Influence of clarification process before alcoholic fermentation.

    Science.gov (United States)

    Burin, Vívian Maria; Caliari, Vinícius; Bordignon-Luiz, Marilde T

    2016-07-01

    The aim of this study was to investigate the effect of adding a fining agent to the must in relation to the fermentation kinetics and the volatile composition of the wine produced. Three fining agents, bentonite, pectinolytic enzyme and silica were applied, separately, to samples of Chardonnay must. It was observed that the addition of a fining agent had a significant influence on the must and wine composition. The must clarified with bentonite showed the lowest nitrogen content and the enzyme addition led to the highest nitrogen content. During the fermentation process, a difference in the consumption rate was observed for each amino acid in relation to the fining agent used in the process. In relation to the volatile composition, the wine produced had different characteristics according to the fining agent added to the must, which was confirmed by separation of the samples using principal component analysis.

  1. Recovering/concentrating of hemicellulosic sugars and acetic acid by nanofiltration and reverse osmosis from prehydrolysis liquor of kraft based hardwood dissolving pulp process.

    Science.gov (United States)

    Ahsan, Laboni; Jahan, M Sarwar; Ni, Yonghao

    2014-03-01

    This work investigated the feasibility of recovering and concentrating sugars and acetic acid (HAc) from prehydrolysis liquor (PHL) of the kraft-based dissolving pulp process prior to fermentation of hemicellulosic sugars, by the combination of activated carbon adsorption, nanofiltration (NF) and reverse osmosis (RO) processes. To reduce the fouling PHL was subjected to adsorption on activated carbon, then the treated PHL (TPHL) passed through a nanofiltration (NF DK) membrane to retain the sugars, and the permeate of acetic acid rich solution was passed through a reverse osmosis membrane (RO SG). It was found that for NF process sugars were concentrated from 48 to 227g/L at a volume reduction factor (VRF) of 5 while 80 to 90% of acetic acid was permeated. For the reverse osmosis process, 68% of acetic acid retention was achieved at pH 4.3 and 500 psi pressure and the HAc concentration increased from 10 to 50g/L.

  2. A process-based emission model of volatile organic compounds from silage sources on farms

    Science.gov (United States)

    Bonifacio, H. F.; Rotz, C. A.; Hafner, S. D.; Montes, F.; Cohen, M.; Mitloehner, F. M.

    2017-03-01

    Silage on dairy farms can emit large amounts of volatile organic compounds (VOCs), a precursor in the formation of tropospheric ozone. Because of the challenges associated with direct measurements, process-based modeling is another approach for estimating emissions of air pollutants from sources such as those from dairy farms. A process-based model for predicting VOC emissions from silage was developed and incorporated into the Integrated Farm System Model (IFSM, v. 4.3), a whole-farm simulation of crop, dairy, and beef production systems. The performance of the IFSM silage VOC emission model was evaluated using ethanol and methanol emissions measured from conventional silage piles (CSP), silage bags (SB), total mixed rations (TMR), and loose corn silage (LCS) at a commercial dairy farm in central California. With transport coefficients for ethanol refined using experimental data from our previous studies, the model performed well in simulating ethanol emission from CSP, TMR, and LCS; its lower performance for SB could be attributed to possible changes in face conditions of SB after silage removal that are not represented in the current model. For methanol emission, lack of experimental data for refinement likely caused the underprediction for CSP and SB whereas the overprediction observed for TMR can be explained as uncertainty in measurements. Despite these limitations, the model is a valuable tool for comparing silage management options and evaluating their relative effects on the overall performance, economics, and environmental impacts of farm production. As a component of IFSM, the silage VOC emission model was used to simulate a representative dairy farm in central California. The simulation showed most silage VOC emissions were from feed lying in feed lanes and not from the exposed face of silage storages. This suggests that mitigation efforts, particularly in areas prone to ozone non-attainment status, should focus on reducing emissions during feeding. For

  3. SCREENING PROCESSED MILK FOR VOLATILE ORGANIC COMPOUNDS USING VACUUM DISTILLATION/GAS CHROMATOGRAPHY/MASS SPECTROMETRY

    Science.gov (United States)

    An adaptation of Office of Solid Waste and Emergency Response' Test Methods for Evaluating Solid Waste Physical/Chemical Methods (SW-846) method 8261 to analyze milk for an expanded list of volatile organic compounds is presented. The milk matriz exhibits a strong affinity for o...

  4. Thermogenic respiratory processes drive the exponential increase of volatile organic compound emissions in Macrozamia cycad cones.

    Science.gov (United States)

    Terry, L Irene; Roemer, Robert B; Booth, David T; Moore, Chris J; Walter, Gimme H

    2016-07-01

    An important outcome of plant thermogenesis is increased emissions of volatiles that mediate pollinator behaviour. We investigated whether the large increase in emissions, mainly the monoterpene ß-myrcene (>90%), during daily thermogenic events of Macrozamia macleayi and lucida cycad cones are due solely to the influence of high cone temperatures or are, instead, a result of increased respiratory rates during thermogenesis. We concurrently measured temperature, oxygen consumption and ß-myrcene emission profiles during thermogenesis of pollen cones under typical environmental temperatures and during experimental manipulations of cone temperatures and aerobic conditions, all in the dark. The exponential rise in ß-myrcene emissions never occurred without a prior, large increase in respiration, whereas an increase in cone temperature alone did not increase emissions. When respiration during thermogenesis was interrupted by anoxic conditions, ß-myrcene emissions decreased. The increased emission rates are not a result of increased cone temperature per se (through increased enzyme activity or volatilization of stored volatiles) but are dependent on biosynthetic pathways associated with increased respiration during thermogenesis that provide the carbon, energy (ATP) and reducing compounds (NADPH) required for ß-myrcene production through the methylerythritol phosphate (MEP) pathway. These findings establish the significant contribution of respiration to volatile production during thermogenesis.

  5. Automated signal processing applied to volatile-based inspection of greenhouse crops

    NARCIS (Netherlands)

    Jansen, R.M.C.; Hofstee, J.W.; Bouwmeester, H.J.; Henten, van E.J.

    2010-01-01

    Gas chromatograph–mass spectrometers (GC-MS) have been used and shown utility for volatile-based inspection of greenhouse crops. However, a widely recognized difficulty associated with GC-MS application is the large and complex data generated by this instrument. As a consequence, experienced analyst

  6. When should fig fruit produce volatiles? Pattern in a ripening process

    Science.gov (United States)

    Borges, Renee M.; Ranganathan, Yuvaraj; Krishnan, Anusha; Ghara, Mahua; Pramanik, Gautam

    2011-11-01

    Ripe fruit need to signal their presence to attract dispersal agents. Plants may employ visual and/or olfactory sensory channels to signal the presence of ripe fruit. Visual signals of ripe fruit have been extensively investigated. However, the volatile signatures of ripe fruit that use olfactorily-oriented dispersers have been scarcely investigated. Moreover, as in flowers, where floral scents are produced at times when pollinators are active (diurnal versus nocturnal), whether plants can modulate the olfactory signal to produce fruit odours when dispersers are active in the diel cycle is completely unknown. We investigated day-night differences in fruit odours in two species of figs, Ficus racemosa and Ficus benghalensis. The volatile bouquet of fruit of F. racemosa that are largely dispersed by bats and other mammals was dominated by fatty acid derivatives such as esters. In this species in which the ripe fig phase is very short, and where the figs drop off soon after ripening, there were no differences between day and night in fruit volatile signature. The volatile bouquet of fruit of F. benghalensis that has a long ripening period, however, and that remain attached to the tree for extended periods when ripe, showed an increase in fatty acid derivatives such as esters and of benzenoids such as benzaldehyde at night when they are dispersed by bats, and an elevation of sesquiterpenes during the day when they are dispersed by birds. For the first time we provide data that suggest that the volatile signal produced by fruit can show diel differences based on the activity period of the dispersal agent.

  7. Effect of post harvest radiation processing and storage on the volatile oil composition and glucosinolate profile of cabbage.

    Science.gov (United States)

    Banerjee, Aparajita; Variyar, Prasad S; Chatterjee, Suchandra; Sharma, Arun

    2014-05-15

    Effect of radiation processing (0.5-2 kGy) and storage on the volatile oil constituents and glucosinolate profile of cabbage was investigated. Among the volatile oil constituents, an enhancement in trans-hex-2-enal was noted on irradiation that was attributed to the increased liberation of precursor linolenic acid mainly from monogalactosyl diacyl glycerol (MGDG). Irradiation also enhanced sinigrin, the major glucosinolate of cabbage that accounted for the enhanced allyl isothiocyanate (AITC) in the volatile oils of the irradiated vegetable. During storage the content of trans-hex-2-enal increased immediately after irradiation and then returned to the basal value within 24h while the content of sinigrin and AITC increased post irradiation and thereafter remained constant during storage. Our findings on the enhancement in potentially important health promoting compounds such as sinigrin and AITC demonstrates that besides extending shelf life and safety, radiation processing can have an additional advantage in improving the nutritional quality of cabbage. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Robust Shared Objects for Non-Volatile Main Memory

    OpenAIRE

    Berryhill, Ryan; Golab, Wojciech; Tripunitara, Mahesh

    2016-01-01

    Research in concurrent in-memory data structures has focused almost exclusively on models where processes are either reliable, or may fail by crashing permanently. The case where processes may recover from failures has received little attention because recovery from conventional volatile memory is impossible in the event of a system crash, during which both the state of main memory and the private states of processes are lost. Future hardware architectures are likely to include various forms ...

  9. A solvent extraction approach to recover acetic acid from mixed waste acids produced during semiconductor wafer process.

    Science.gov (United States)

    Shin, Chang-Hoon; Kim, Ju-Yup; Kim, Jun-Young; Kim, Hyun-Sang; Lee, Hyang-Sook; Mohapatra, Debasish; Ahn, Jae-Woo; Ahn, Jong-Gwan; Bae, Wookeun

    2009-03-15

    Recovery of acetic acid (HAc) from the waste etching solution discharged from silicon wafer manufacturing process has been attempted by using solvent extraction process. For this purpose 2-ethylhexyl alcohol (EHA) was used as organic solvent. In the pre-treatment stage >99% silicon and hydrofluoric acid was removed from the solution by precipitation. The synthesized product, Na(2)SiF(6) having 98.2% purity was considered of commercial grade having good market value. The waste solution containing 279 g/L acetic acid, 513 g/L nitric acid, 0.9 g/L hydrofluoric acid and 0.030 g/L silicon was used for solvent extraction study. From the batch test results equilibrium conditions for HAc recovery were optimized and found to be 4 stages of extraction at an organic:aqueous (O:A) ratio of 3, 4 stages of scrubbing and 4 stages of stripping at an O:A ratio of 1. Deionized water (DW) was used as stripping agent to elute HAc from organic phase. In the whole batch process 96.3% acetic acid recovery was achieved. Continuous operations were successfully conducted for 100 h using a mixer-settler to examine the feasibility of the extraction system for its possible commercial application. Finally, a complete process flowsheet with material balance for the separation and recovery of HAc has been proposed.

  10. Real-time monitoring system for improving corona electrostatic separation in the process of recovering waste printed circuit boards.

    Science.gov (United States)

    Li, Jia; Zhou, Quan; Xu, Zhenming

    2014-12-01

    Although corona electrostatic separation is successfully used in recycling waste printed circuit boards in industrial applications, there are problems that cannot be resolved completely, such as nonmetal particle aggregation and spark discharge. Both of these problems damage the process of separation and are not easy to identify during the process of separation in industrial applications. This paper provides a systematic study on a real-time monitoring system. Weight monitoring systems were established to continuously monitor the separation process. A Virtual Instrumentation program written by LabVIEW was utilized to sample and analyse the mass increment of the middling product. It includes four modules: historical data storage, steady-state analysis, data computing and alarm. Three kinds of operating conditions were used to verify the applicability of the monitoring system. It was found that the system achieved the goal of monitoring during the separation process and realized the function of real-time analysis of the received data. The system also gave comprehensible feedback on the accidents of material blockages in the feed inlet and high-voltage spark discharge. With the warning function of the alarm system, the whole monitoring system could save the human cost and help the new technology to be more easily applied in industry. © The Author(s) 2014.

  11. Temporal variation, regional sources, and removal processes of volatile organic compounds in New England

    Science.gov (United States)

    Russo, Rachel S.

    This dissertation describes three research projects with the common objective of characterizing the influence of volatile organic compounds (VOCs) on air quality in New England using measurements made over multiple years (2002-2008) and from different sampling locations. The specific objectives include identifying sources (direct emission or secondary production), quantifying mixing ratios, and characterizing the chemical (i.e., oxidation, photolysis) and physical (i.e., transport, mixing) processes which regulate the distributions of VOCs in the troposphere over southeastern New Hampshire. Chapters 2 and 3 discuss the seasonal and interannual variability of nonmethane hydrocarbons (NMHCs), selected halocarbons, and alkyl nitrates using measurements from canister samples collected at Thompson Farm in Durham, NH throughout January 2004-February 2008. Several anthropogenic and biogenic sources of NMHCs and halocarbons were identified based on correlations with tracer compounds and comparisons with source signatures. Additionally, evidence for the dry deposition of alkyl nitrates of night was observed which is a previously unaccounted for removal mechanism. Analysis of alkyl nitrate/parent hydrocarbon ratios, measurements made onboard the NOAA R/V Ronald H. Brown during the 2002 New England Air Quality Study, and canister samples collected throughout the Great Bay estuary in August 2003 are presented to assess the relative contributions of anthropogenic and marine sources of alkyl nitrates. The research described in Chapter 4 used measurements of VOCs made at an inland (Thompson Farm) and an offshore (Appledore Island) site to identify evidence of chlorine initiated oxidation of VOCs, estimate chlorine atom (Cl) concentrations during two summers and for different transport sectors, and assess the potential influence of chlorine chemistry on the oxidative capacity of the troposphere over coastal New Hampshire. Comparable Cl concentrations were estimated using a novel

  12. Inorganic analyses of volatilized and condensed species within prototypic Defense Waste Processing Facility (DWPF) canistered waste

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C.M.

    1992-06-30

    The high-level radioactive waste currently stored in carbon steel tanks at the Savannah River Site (SRS) will be immobilized in a borosilicate glass in the Defense Waste Processing Facility (DWPF). The canistered waste will be sent to a geologic repository for final disposal. The Waste Acceptance Preliminary Specifications (WAPS) require the identification of any inorganic phases that may be present in the canister that may lead to internal corrosion of the canister or that could potentially adversely affect normal canister handling. During vitrification, volatilization of mixed (Na, K, Cs)Cl, (Na, K, Cs){sub 2}SO{sub 4}, (Na, K, Cs)BF{sub 4}, (Na, K){sub 2}B{sub 4}O{sub 7} and (Na,K)CrO{sub 4} species from glass melt condensed in the melter off-gas and in the cyclone separator in the canister pour spout vacuum line. A full-scale DWPF prototypic canister filled during Campaign 10 of the SRS Scale Glass Melter was sectioned and examined. Mixed (NaK)CI, (NaK){sub 2}SO{sub 4}, (NaK) borates, and a (Na,K) fluoride phase (either NaF or Na{sub 2}BF{sub 4}) were identified on the interior canister walls, neck, and shoulder above the melt pour surface. Similar deposits were found on the glass melt surface and on glass fracture surfaces. Chromates were not found. Spinel crystals were found associated with the glass pour surface. Reference amounts of the halides and sulfates were found retained in the glass and the glass chemistry, including the distribution of the halides and sulfates, was homogeneous. In all cases where rust was observed, heavy metals (Zn, Ti, Sn) from the cutting blade/fluid were present indicating that the rust was a reaction product of the cutting fluid with glass and heat sensitized canister or with carbon-steel contamination on canister interior. Only minimal water vapor is present so that internal corrosion of the canister, will not occur.

  13. Emerging Equity Market Volatility

    OpenAIRE

    Geert Bekaert; Harvey, Campbell R.

    1995-01-01

    Returns in emerging capital markets are very different from returns in developed markets. While most previous research has focused on average returns, we analyze the volatility of the returns in emerging equity markets. We characterize the time-series of volatility in emerging markets and explore the distributional foundations of the variance process. Of particular interest is evidence of asymmetries in volatility and the evolution of the variance process after periods of capital market refor...

  14. From quantum mechanics to finance: Microfoundations for jumps, spikes and high volatility phases in diffusion price processes

    Science.gov (United States)

    Henkel, Christof

    2017-03-01

    We present an agent behavior based microscopic model that induces jumps, spikes and high volatility phases in the price process of a traded asset. We transfer dynamics of thermally activated jumps of an unexcited/excited two state system discussed in the context of quantum mechanics to agent socio-economic behavior and provide microfoundations. After we link the endogenous agent behavior to price dynamics we establish the circumstances under which the dynamics converge to an Itô-diffusion price processes in the large market limit.

  15. Comparison of Diafiltration and Size-Exclusion Chromatography to Recover Hemicelluloses From Process Water From Thermomechanical Pulping of Spruce

    Science.gov (United States)

    Andersson, Alexandra; Persson, Tobias; Zacchi, Guido; Stålbrand, Henrik; Jönsson, Ann-Sofi

    Hemicelluloses constitute one of the most abundant renewable resources on earth. To increase their utilization, the isolation of hemicelluloses from industrial biomass side-streams would be beneficial. A method was investigated to isolate hemicelluloses from process water from a thermomechanical pulp mill. The method consists of three steps: removal of solids by microfiltration, preconcentration of the hemicelluloses by ultrafiltration, and purification by either size-exclusion chromatography (SEC) or diafiltration. The purpose of the final purification step is to separate hemicelluloses from small oligosaccharides, monosaccharides, and salts. The ratio between galactose, glucose, and mannose in oligo- and polysaccharides after preconcentration was 0.8∶1∶2.8, which is similar to that found in galactoglucomannan. Continuous diafiltration was performed using a composite fluoro polymer membrane with cutoff of 1000 Da. After diafiltration with four diavolumes the purity of the hemicelluloses was 77% (gram oligo- and polysaccharides/ gram total dissolved solids) and the recovery was 87%. Purification by SEC was performed with 5, 20, and 40% sample loadings, respectively and a flow rate of 12 or 25 mL/min (9 or 19 cm/h). The purity of hemicelluloses after SEC was approx 82%, and the recovery was above 99%. The optimal sample load and flow rate were 20% and 25 mL/min, respectively. The process water from thermomechanical pulping of spruce is inexpensive. Thus, the recovery of hemicelluloses is not of main importance. If the purity of 77%, obtained with diafiltration, is sufficient for the utilization of the hemicelluloses, diafiltration probably offers a less expensive alternative in this application.

  16. A three-prong strategy to develop functional food using protein isolates recovered from chicken processing by-products with isoelectric solubilization/precipitation.

    Science.gov (United States)

    Tahergorabi, Reza; Sivanandan, Litha; Beamer, Sarah K; Matak, Kristen E; Jaczynski, Jacek

    2012-09-01

    Skin-on bone-in chicken drumsticks were processed with isoelectric solubilization/precipitation to recover muscle proteins. The drumsticks were used as a model for dark chicken meat processing by-products. The main objective of this study was conversion of dark chicken meat processing by-products to restructured functional food product. An attempt was made to develop functional food product that would resemble respective product made from boneless skinless chicken breast meat. A three-prong strategy to address diet-driven cardiovascular disease (CVD)with a functional food was used in this study. The strategy included addition of three ingredients with well-documented cardiovascular benefits: (i) ω-3 polyunsaturated fatty acid-rich oil (flaxseed-algae, 9:1); (ii) soluble fiber; and (iii) salt substitute. Titanium dioxide, potato starch, polyphosphate, and transglutaminase were also added. The batters were formulated and cooked resulting in heat-set gels. Color (L*a*b*), texture (torsion test, Kramer shear test, and texture profile analysis), thermal denaturation (differential scanning calorimetry), and gelation (dynamic rheology) of chicken drumstick gels and chicken breast gels were determined and compared. Chicken drumstick gels generally had comparable color and texture properties to the gels made from chicken breast meat. The endothermic transition (thermal denaturation) of myosin was more pronounced and gelation properties were better for the drumstick gels. This study demonstrated a feasibility to develop functional food made of muscle proteins recovered with isoelectric solubilization/precipitation from low-value dark chicken meat processing by-products. The functional food developed in this study was enriched with CVD-beneficial nutrients and had comparable instrumental quality attributes to respective products made of chicken breast meat. Although the results of this study point towards the potential for a novel, marketable functional food product, sensory

  17. Impact of thermal and nonthermal processing technologies on unfermented apple cider aroma volatiles.

    Science.gov (United States)

    Azhu Valappil, Zareena; Fan, Xuetong; Zhang, Howard Q; Rouseff, Russell L

    2009-02-11

    Aroma composition and microbial quality of identical lots of apple cider treated by pulsed electric field (PEF), ultraviolet irradiation (UV), or thermal pasteurization stored at 4 degrees C were compared at 0 and 4 weeks. Conditions were optimized to achieve identical 5 log reductions in Escherichia coli K12 for each treatment. PEF and thermal pasteurization maintained acceptable microbial quality for 4 weeks, but UV samples fermented after 2 weeks. Twenty-eight volatiles were quantified using gas chromatography-mass spectrometry (GC-MS) and odor activity values (OAV) determined. OAVs of 69:hexyl acetate, 41:hexanal, 25:2-methylbutyl acetate, 23:2-methyl ethyl butyrate, and 14:2-(E)-hexenal were observed for the control cider. Significant differences (p ciders only after 4 weeks of storage. Thermal samples lost 30% of the major ester and aldehyde volatiles during storage with significant decreases (p cider, hexanal and 2-(E)-hexenal were completely lost after 4 weeks of storage. Microbial spoilage in UV cider after 4 weeks of storage was chemically confirmed by the detection of the microbial metabolite 1,3-pentadiene. PEF cider lost cider.

  18. Oil and stock market volatility: A multivariate stochastic volatility perspective

    Energy Technology Data Exchange (ETDEWEB)

    Vo, Minh, E-mail: minh.vo@metrostate.edu

    2011-09-15

    This paper models the volatility of stock and oil futures markets using the multivariate stochastic volatility structure in an attempt to extract information intertwined in both markets for risk prediction. It offers four major findings. First, the stock and oil futures prices are inter-related. Their correlation follows a time-varying dynamic process and tends to increase when the markets are more volatile. Second, conditioned on the past information, the volatility in each market is very persistent, i.e., it varies in a predictable manner. Third, there is inter-market dependence in volatility. Innovations that hit either market can affect the volatility in the other market. In other words, conditioned on the persistence and the past volatility in their respective markets, the past volatility of the stock (oil futures) market also has predictive power over the future volatility of the oil futures (stock) market. Finally, the model produces more accurate Value-at-Risk estimates than other benchmarks commonly used in the financial industry. - Research Highlights: > This paper models the volatility of stock and oil futures markets using the multivariate stochastic volatility model. > The correlation between the two markets follows a time-varying dynamic process which tends to increase when the markets are more volatile. > The volatility in each market is very persistent. > Innovations that hit either market can affect the volatility in the other market. > The model produces more accurate Value-at-Risk estimates than other benchmarks commonly used in the financial industry.

  19. ALH85085: a unique volatile-poor carbonaceous chondrite with possible implications for nebular fractionation processes

    Science.gov (United States)

    Grossman, J.N.; Rubin, A.E.; MacPherson, G.J.

    1988-01-01

    Allan Hills 85085 is a unique chondrite with affinities to the Al Rais-Renazzo clan of carbonaceous chondrites. Its constituents are less than 50 ??m in mean size. Chondrules and microchondrules of all textures are present; nonporphyritic chondrules are unusually abundant. The mean compositions of porphyritic, nonporphyritic and barred olivine chondrules resemble those in ordinary chondrites except that they are depleted in volatile elements. Ca-, Al-rich inclusions are abundant and largely free of nebular alteration; they comprise types similar to those in CM and CO chondrites, as well as unique types. Calcium dialuminate occurs in several inclusions. Metal, silicate and sulfide compositions are close to those in CM-CO chondrites and Al Rais and Renazzo. C1-chondrite clasts and metal-rich "reduced" clasts are present, but opaque matrix is absent. Siderophile abundances in ALH85085 are extremely high (e.g., Fe Si = 1.7 ?? solar), and volatiles are depleted (e.g., Na Si = 0.25 ?? solar, S Si = 0.03 ?? solar). Nonvolatile lithophile abundances are similar to those in Al Rais, Renazzo, and CM and CO chondrites. ALH85085 agglomerated when temperatures in the nebula were near 1000 K, in the same region where Renazzo, Al Rais and the CI chondrites formed. Agglomeration of high-temperature material may thus be a mechanism by which the fractionation of refractory lithophiles occurred in the nebula. Chondrule formation must have occurred at high temperatures when clumps of precursors were small. After agglomeration, ALH85085 was annealed and lightly shocked. C1 and other clasts were subsequently incorporated during late-stage brecciation. ?? 1988.

  20. Volatile compounds of dry-cured Iberian ham as affected by the length of the curing process.

    Science.gov (United States)

    Ruiz, J; Ventanas, J; Cava, R; Andrés, A; García, C

    1999-05-01

    Volatile compounds from 10 dry-cured Iberian hams ripened for two different processing times, a prolonged traditional one (600 days) and a shortened process (420 days), were analysed by purge and trap coupled to gas chromatography-mass spectroscopy. Eighty-three compounds were identified which agreed with the major classes found in other ham types. The amount of methyl branched alkanes was much higher than in other dry-cured ham types, probably due to the feeding regime. The percentages of 2- and 3-methylbutanal were higher (p<0.0001 and p<0.0003, respectively) in the longer aged hams, whereas the amounts of some compounds from lipid oxidation decreased from 420 to 600 days aging. In agreement with these observations, 600-day hams had higher scores for those odour and flavour traits usually considered to be positive attributes and lower scores for rancidity. A positive and significant correlation between 2-methyl butanal and cured flavour was found.

  1. Children's (In)ability to Recover from Garden Paths in a Verb-Final Language: Evidence for Developing Control in Sentence Processing

    Science.gov (United States)

    Choi, Youngon; Trueswell, John C.

    2010-01-01

    An eye-tracking study explored Korean-speaking adults' and 4- and 5-year-olds' ability to recover from misinterpretations of temporarily ambiguous phrases during spoken language comprehension. Eye movement and action data indicated that children, but not adults, had difficulty in recovering from these misinterpretations despite strong…

  2. Volatile Metabolites

    Directory of Open Access Journals (Sweden)

    Daryl D. Rowan

    2011-11-01

    Full Text Available Volatile organic compounds (volatiles comprise a chemically diverse class of low molecular weight organic compounds having an appreciable vapor pressure under ambient conditions. Volatiles produced by plants attract pollinators and seed dispersers, and provide defense against pests and pathogens. For insects, volatiles may act as pheromones directing social behavior or as cues for finding hosts or prey. For humans, volatiles are important as flavorants and as possible disease biomarkers. The marine environment is also a major source of halogenated and sulfur-containing volatiles which participate in the global cycling of these elements. While volatile analysis commonly measures a rather restricted set of analytes, the diverse and extreme physical properties of volatiles provide unique analytical challenges. Volatiles constitute only a small proportion of the total number of metabolites produced by living organisms, however, because of their roles as signaling molecules (semiochemicals both within and between organisms, accurately measuring and determining the roles of these compounds is crucial to an integrated understanding of living systems. This review summarizes recent developments in volatile research from a metabolomics perspective with a focus on the role of recent technical innovation in developing new areas of volatile research and expanding the range of ecological interactions which may be mediated by volatile organic metabolites.

  3. Changes in guava (Psidium guajava L. var. Paluma nectar volatile compounds concentration due to thermal processing and storage

    Directory of Open Access Journals (Sweden)

    Maria Ivaneide Coutinho Correa

    2010-12-01

    Full Text Available Guava nectars were formulated for approximately 10, 12, or 14 ºBrix, with 40% guava pulp. Sodium benzoate, 500 mg.kg-1 was used as preservative. The Brix value was adjusted with saturated sucrose syrup. The guava nectar was pasteurized (85 ºC/42 seconds in tubular heat exchanger and then hot filled in 500 mL white glass bottles. The products were stored either at room temperature (25 ± 5 ºC or refrigerated (5 ± 2 ºC under fluorescent light exposure and analyzed on the day after processing (time zero and also 40, 80, and 120 days of storage. Eight compounds were identified and quantified by Gas Chromatography (GC -Mass Spectrometry (MS: hexanal, (E-hex-2-enal, 1-hexenol, (Z-hex-3-enol, (Z-hex-3-enyl acetate, phenyl-3-propyl acetate, cinnamyl acetate, and acetic acid. There was no significant effect of thermal treatment on the volatile compound concentrations, except for a significant decrease (p = 0.0001 in hexanal and (Z-hex-3-enyl acetate (p = 0.0029. As for the storage time, there was a much greater decrease in the esters contents, such as (Z-hex-3-enyl and phenyl-3-propyl acetates. Cinnamyl acetate had the greatest decrease over storage time. Refrigeration was better than room temperature for guava nectar volatile compounds stability over storage time, mainly for esters compounds, which are important for the product aroma and flavor

  4. Solid-phase microextraction and gas chromatography-mass spectrometry of volatile compounds from avocado puree after microwave processing.

    Science.gov (United States)

    López, Mercedes G; Guzmán, G R; Dorantes, A L

    2004-05-14

    Microwave processing offers an alternative to blanch fruits and vegetables, since the application of high temperature and short time often results in minimum damage. An experimental design was used to investigate the effect of microwave time, pH, and avocado leaves (independent variables) on avocado flavor (response) using solid-phase microextraction (SPME)-GC-MS. Among the fully characterized flavor volatiles, 19 compounds were derived from lipid oxidation and only 4 from the avocado leaves. The main components derived from lipids were aldehydes, ketones and alcohols. Terpenoids, estragole, and 2-hexenal [E] were volatiles derived from avocado leaves. When leaves were added to fresh and microwaved avocado terpenoids and 2-hexenal [E]/hexanal ratio increased, this behavior was considered to have a positive effect on the sensorial quality of the product. From the statistical analysis of the experimental design, it was possible to determinate that the most important factors influencing the abundance of flavor compounds derived from lipids were microwave time and pH. Maximum values of these compounds were detected at high levels of microwave time and low values of pH. On the other hand, response surface of terpenoids and estragole showed an increment when microwave time and avocado leaf was increased. The region of optimum response was 30 s microwave time, pH 5.5, and 1% of avocado leaf.

  5. Problem Solving for Volatilizing Situation in Nursing: Developing Thinking Process Supporting System using NursingNAVI® Contents.

    Science.gov (United States)

    Tsuru, Satoko; Wako, Fumiko; Omori, Miho; Sudo, Kumiko

    2015-01-01

    We have identified three foci of the nursing observation and nursing action respectively. Using these frameworks, we have developed the structured knowledge model for a number of diseases and medical interventions. We developed this structure based NursingNAVI® contents collaborated with some quality centered hospitals. Authors analysed the nursing care documentations of post-gastrectomy patients in light of the standardized nursing care plan in the "NursingNAVI®" developed by ourselves and revealed the "failure to observe" and "failure to document", which leaded to the volatility of the patients' data, conditions and some situation. This phenomenon should have been avoided if nurses had employed a standardized nursing care plan. So, we developed thinking process support system for planning, delivering, recording and evaluating in daily nursing using NursingNAVI® contents. A hospital decided to use NursingNAVI® contents in HIS. It was suggested that the system has availability for nursing OJT and time reduction of planning and recording without volatilizing situation.

  6. Pricing Volatility of Stock Returns with Volatile and Persistent Components

    DEFF Research Database (Denmark)

    Zhu, Jie

    2009-01-01

    This paper introduces a two-component volatility model based on first moments of both components to describe the dynamics of speculative return volatility. The two components capture the volatile and the persistent part of volatility, respectively. The model is applied to 10 Asia-Pacific stock...... markets. Their in-mean effects on returns are tested. The empirical results show that the persistent component is much more important for the volatility dynamic process than is the volatile component. However, the volatile component is found to be a significant pricing factor of asset returns for most...... markets. A positive or risk-premium effect exists between the return and the volatile component, yet the persistent component is not significantly priced for the return dynamic process....

  7. Mechanochemical process to recover heavy metals from industrial ash; Procedimenti meccanochimici per l'estrazione di metalli pesanti da ceneri industriali

    Energy Technology Data Exchange (ETDEWEB)

    La Barbera, A.; Bimbi, C.; De Francesco, M.; Padella, F. [ENEA Centro Ricerche Casaccia, Rome (Italy). Dipt. Innovazione; Ranaldi, E. [ENEA Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente

    1999-07-01

    An innovative mechanochemical process has been conceived to recover heavy metals from industrial ashes. The low environmental impact process is based on the transformation of heavy metals oxides into soluble salts. In particular high energy ball milling has been successfully applied on real samples from iron electrometallurgy. Heavy metals extractions higher than the ones resulting from the typical acid attack were obtained. [Italian] A partire da simulazioni termidinamiche, e' stato ideato un innovativo processo meccanochimico a basso impatto ambientale per il recupero di metalli pesanti da ceneri pericolose di origine industriale. Il processo, che prevede la conversione in fasi solubili di metalli pesanti presenti nelle ceneri sotto forma di ossidi misti insolubili, e' stato sperimentato con successo sia su campioni di laboratorio che su campioni reali. In particolare la macinazione ad alta energia e' stata applicata a campioni di cenere provenienti da elettrometallurgia del ferro, con un elevato contenuto di zinco, ottenendo risultati migliori di quelli ottenibili da un tradizionale attacco acido.

  8. The Search for a Volatile Human Specific Marker in the Decomposition Process.

    Directory of Open Access Journals (Sweden)

    E Rosier

    Full Text Available In this study, a validated method using a thermal desorber combined with a gas chromatograph coupled to mass spectrometry was used to identify the volatile organic compounds released during decomposition of 6 human and 26 animal remains in a laboratory environment during a period of 6 months. 452 compounds were identified. Among them a human specific marker was sought using principle component analysis. We found a combination of 8 compounds (ethyl propionate, propyl propionate, propyl butyrate, ethyl pentanoate, pyridine, diethyl disulfide, methyl(methylthioethyl disulfide and 3-methylthio-1-propanol that led to the distinction of human and pig remains from other animal remains. Furthermore, it was possible to separate the pig remains from human remains based on 5 esters (3-methylbutyl pentanoate, 3-methylbutyl 3-methylbutyrate, 3-methylbutyl 2-methylbutyrate, butyl pentanoate and propyl hexanoate. Further research in the field with full bodies has to corroborate these results and search for one or more human specific markers. These markers would allow a more efficiently training of cadaver dogs or portable detection devices could be developed.

  9. Change in Color and Volatile Composition of Skim Milk Processed with Pulsed Electric Field and Microfiltration Treatments or Heat Pasteurization

    Directory of Open Access Journals (Sweden)

    Anupam Chugh

    2014-04-01

    Full Text Available Non-thermal processing methods, such as pulsed electric field (PEF and tangential-flow microfiltration (TFMF, are emerging processing technologies that can minimize the deleterious effects of high temperature short time (HTST pasteurization on quality attributes of skim milk. The present study investigates the impact of PEF and TFMF, alone or in combination, on color and volatile compounds in skim milk. PEF was applied at 28 or 40 kV/cm for 1122 to 2805 µs, while microfiltration (MF was conducted using membranes with three pore sizes (lab-scale 0.65 and 1.2 µm TFMF, and pilot-scale 1.4 µm MF. HTST control treatments were applied at 75 or 95 °C for 20 and 45 s, respectively. Noticeable color changes were observed with the 0.65 µm TFMF treatment. No significant color changes were observed in PEF-treated, 1.2 µm TFMF-treated, HTST-treated, and 1.4 µm MF-treated skim milk (p ≥ 0.05 but the total color difference indicated better color retention with non-thermal preservation. The latter did not affect raw skim milk volatiles significantly after single or combined processing (p ≥ 0.05, but HTST caused considerable changes in their composition, including ketones, free fatty acids, hydrocarbons, and sulfur compounds (p < 0.05. The findings indicate that for the particular thermal and non-thermal treatments selected for this study, better retention of skim milk color and flavor components were obtained for the non-thermal treatments.

  10. Latent Integrated Stochastic Volatility, Realized Volatility, and Implied Volatility: A State Space Approach

    DEFF Research Database (Denmark)

    Bach, Christian; Christensen, Bent Jesper

    We include simultaneously both realized volatility measures based on high-frequency asset returns and implied volatilities backed out of individual traded at the money option prices in a state space approach to the analysis of true underlying volatility. We model integrated volatility as a latent...... fi…rst order Markov process and show that our model is closely related to the CEV and Barndorff-Nielsen & Shephard (2001) models for local volatility. We show that if measurement noise in the observable volatility proxies is not accounted for, then the estimated autoregressive parameter in the latent...... process is downward biased. Implied volatility performs better than any of the alternative realized measures when forecasting future integrated volatility. The results are largely similar across the stock market (S&P 500), bond market (30-year U.S. T-bond), and foreign currency exchange market ($/£ )....

  11. Emission of volatile organic compounds from domestic coal stove with the actual alternation of flaming and smoldering combustion processes.

    Science.gov (United States)

    Liu, Chengtang; Zhang, Chenglong; Mu, Yujing; Liu, Junfeng; Zhang, Yuanyuan

    2017-02-01

    Volatile organic compounds (VOCs) emissions from the chimney of a prevailing domestic stove fuelled with raw bituminous coal were measured under flaming and smoldering combustion processes in a farmer's house. The results indicated that the concentrations of VOCs quickly increased after the coal loading and achieved their peak values in a few minutes. The peak concentrations of the VOCs under the smoldering combustion process were significantly higher than those under the flaming combustion process. Alkanes accounted for the largest proportion (43.05%) under the smoldering combustion, followed by aromatics (28.86%), alkenes (21.91%), carbonyls (5.81%) and acetylene (0.37%). The emission factors of the total VOCs under the smoldering combustion processes (5402.9 ± 2031.8 mg kg(-1)) were nearly one order of magnitude greater than those under the flaming combustion processes (559.2 ± 385.9 mg kg(-1)). Based on the VOCs emission factors obtained in this study and the regional domestic coal consumption, the total VOCs emissions from domestic coal stoves was roughly estimated to be 1.25 × 10(8) kg a(-1) in the Beijing-Tianjin-Hebei region. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Pricing Volatility of Stock Returns with Volatile and Persistent Components

    DEFF Research Database (Denmark)

    Zhu, Jie

    In this paper a two-component volatility model based on the component's first moment is introduced to describe the dynamic of speculative return volatility. The two components capture the volatile and persistent part of volatility respectively. Then the model is applied to 10 Asia-Pacific stock m......, a positive or risk-premium effect exists between return and the volatile component, yet the persistent component is not significantly priced for return dynamic process.......In this paper a two-component volatility model based on the component's first moment is introduced to describe the dynamic of speculative return volatility. The two components capture the volatile and persistent part of volatility respectively. Then the model is applied to 10 Asia-Pacific stock...... markets. Their in-mean effects on return are also tested. The empirical results show that the persistent component accounts much more for volatility dynamic process than the volatile component. However the volatile component is found to be a significant pricing factor of asset returns for most markets...

  13. Slab-derived halogens and noble gases illuminate closed system processes controlling volatile element transport into the mantle wedge

    Science.gov (United States)

    Kobayashi, Masahiro; Sumino, Hirochika; Nagao, Keisuke; Ishimaru, Satoko; Arai, Shoji; Yoshikawa, Masako; Kawamoto, Tatsuhiko; Kumagai, Yoshitaka; Kobayashi, Tetsuo; Burgess, Ray; Ballentine, Chris J.

    2017-01-01

    Halogen and noble gas systematics are powerful tracers of volatile recycling in subduction zones. We present halogen and noble gas compositions of mantle peridotites containing H2O-rich fluid inclusions collected at volcanic fronts from two contrasting subduction zones (the Avacha volcano of Kamchatka arc and the Pinatubo volcano of Luzon arcs) and orogenic peridotites from a peridotite massif (the Horoman massif, Hokkaido, Japan) which represents an exhumed portion of the mantle wedge. The aims are to determine how volatiles are carried into the mantle wedge and how the subducted fluids modify halogen and noble gas compositions in the mantle. The halogen and noble gas signatures in the H2O-rich fluids are similar to those of marine sedimentary pore fluids and forearc and seafloor serpentinites. This suggests that marine pore fluids in deep-sea sediments are carried by serpentine and supplied to the mantle wedge, preserving their original halogen and noble gas compositions. We suggest that the sedimentary pore fluid-derived water is incorporated into serpentine through hydration in a closed system along faults at the outer rise of the oceanic, preserving Cl/H2O and 36Ar/H2O values of sedimentary pore fluids. Dehydration-hydration process within the oceanic lithospheric mantle maintains the closed system until the final stage of serpentine dehydration. The sedimentary pore fluid-like halogen and noble gas signatures in fluids released at the final stage of serpentine dehydration are preserved due to highly channelized flow, whereas the original Cl/H2O and 36Ar/H2O ratios are fractionated by the higher incompatibility of halogens and noble gases in hydrous minerals.

  14. Plant volatiles.

    Science.gov (United States)

    Baldwin, Ian T

    2010-05-11

    Plant volatiles are the metabolites that plants release into the air. The quantities released are not trivial. Almost one-fifth of the atmospheric CO2 fixed by land plants is released back into the air each day as volatiles. Plants are champion synthetic chemists; they take advantage of their anabolic prowess to produce volatiles, which they use to protect themselves against biotic and abiotic stresses and to provide information - and potentially disinformation - to mutualists and competitors alike. As transferors of information, volatiles have provided plants with solutions to the challenges associated with being rooted in the ground and immobile.

  15. Ters Para İkamesi Süreci ve Döviz Kuru Oynaklığı: Türkiye Örneği = Reverse Currency Substitution Process and Exchange Rate Volatility: The Turkish Case

    Directory of Open Access Journals (Sweden)

    Burak DARICI

    2009-01-01

    Full Text Available Theoretical and empirical literature shows that there is a significant relation between currency substitution and exchange rate volatility, and this volatility affects money demand significantly. This study examines the relation between reverse currency substitution and the volatility in exchange rate as well as the effects of this volatility on the demand for money. We used monthly data covering the period of 2001/04-2006/12, which started with the implementation of Program for Transition to a Strong Economy. Following the literature, we employed E-GARCH method in exchange rate volatility modeling and Pesaran et al (2001 bounds test approach in the estimation of money demand function. In accordance with the theoretical expectations, we found that with the increase in reverse currency substitution the exchange rate volatility decreased. Moreover, the decline in the volatility of exchange rate increased the money demand, i.e. accelerated the reverse currency substitution process.

  16. The reduction of iron oxides by volatiles in a rotary hearth furnace process: Part III. The simulation of volatile reduction in a multi-layer rotary hearth furnace process

    Science.gov (United States)

    Sohn, I.; Fruehan, R. J.

    2006-04-01

    For reduction of iron oxides by volatiles from coal, the major reductant was found to be H2, and it can affect the overall reduction of iron oxides. In this study, the reduction by actual volatiles of composite pellets at 1000 °C was studied. The volatile reduction of the hand-packed Fe2O3/coal composite pellet as it is devolatilizing out of the pellet was found to be negligible. However, the reduction of iron oxide pellets at the top layer by volatiles from the bottom layers of a three-layer pellet geometry was observed to be about 15 pct. From the morphological observations of partially reduced pellets and the computed rates of bulk mass transfer, volatile reduction appears to be controlled by a mixed-controlled mechanism of bulk gas mass transfer and the limited-mixed control reduction kinetics. Using the reduction rate obtained from the single pellet experiments with pure hydrogen and extrapolating this rate to an H2 partial pressure corresponding to the H2 from the volatiles, an empirical relationship was obtained to approximately predict the amount of volatile reduction up to 20 pct.

  17. Stable carbon isotope ratio and its use in determination of photochemical processing of ambient volatile organic compounds

    Science.gov (United States)

    Kornilova, A.; Saccon, M. S.; Rudolph, J.; Huang, L.

    2012-12-01

    Stable Carbon Isotopic Composition measurement technique can provide valuable information about trace gas processing in the atmosphere. It can not only be used to distinguish physical processes such as dilution and mixing from photochemical ageing, but also can be an important tool in identification of sources, calculating the photochemical age and qualitatively and quantitatively connecting precursors with their atmospheric products. Even though isotopic composition analysis is a valuable technique, its use is hindered by the low concentrations of compounds in the atmosphere, complexity of the samples and complex measuring instrumentation. We have developed and validated sampling and instrumental analysis techniques that can be used to perform isotopic composition measurements of volatile organic compounds (VOC) and to apply these methods to analysis of ambient samples. In this poster application of this newly developed sampling and analysis techniques will be presented and discussed using concentrations and stable carbon isotope ratios of ambient VOC collected during 2009-2010 at urban and remote locations of southern Ontario. Photochemical ages determined using conventional hydrocarbon clock will be compared to ones determined with photochemical ages derived from isotope hydrocarbon clock. Advantages of the use of stable carbon isotope ratios over other conventional methods will be outlined and applications of isotope hydrocarbon clock in air quality monitoring will be discussed.

  18. The investment in scent: time-resolved metabolic processes in developing volatile-producing Nigella sativa L. seeds.

    Directory of Open Access Journals (Sweden)

    Wentao Xue

    Full Text Available The interplay of processes in central and specialized metabolisms during seed development of Nigella sativa L. was studied by using a high-throughput metabolomics technology and network-based analysis. Two major metabolic shifts were identified during seed development: the first was characterized by the accumulation of storage lipids (estimated as total fatty acids and N-compounds, and the second by the biosynthesis of volatile organic compounds (VOCs and a 30% average decrease in total fatty acids. Network-based analysis identified coordinated metabolic processes during development and demonstrated the presence of five network communities. Enrichment analysis indicated that different compound classes, such as sugars, amino acids, and fatty acids, are largely separated and over-represented in certain communities. One community displayed several terpenoids and the central metabolites, shikimate derived amino acids, raffinose, xylitol and glycerol-3-phosphate. The latter are related to precursors of the mevalonate-independent pathway for VOC production in the plastid; also plastidial fatty acid 18∶3n-3 abundant in "green" seeds grouped with several major terpenes. The findings highlight the interplay between the components of central metabolism and the VOCs. The developmental regulation of Nigella seed metabolism during seed maturation suggests a substantial re-allocation of carbon from the breakdown of fatty acids and from N-compounds, probably towards the biosynthesis of VOCs.

  19. Recovering from Delivery

    Science.gov (United States)

    ... suicidal thoughts, or any thoughts of harming your baby While recovering from delivery can be a lot to handle, things will get easier. Before you know it, you will be able to fully focus on enjoying your new baby. Reviewed by: Larissa Hirsch, MD Date reviewed: June ...

  20. Investigation of non-volatile additives on the process of distillation of hydrocarbon mixtures

    Directory of Open Access Journals (Sweden)

    М.Б. Степанов

    2009-02-01

    Full Text Available  The given results of researches of influence of nonvolatile additives on processes of distillation of individual hydrocarbons and their mixes, including petroleum and mineral oil. With the help of the developed computer system of the continuous control of distillation it is shown, that at the presence of small amounts of the additive decrease of temperature of the beginning of boiling of hydrocarbons is observed, their speeds of banish and exits of light fuel mineral oil grow during initial oil refining

  1. Modelling of a biofiltration process of volatile organic compound mixtures in a biofilter

    Directory of Open Access Journals (Sweden)

    Rasa Vaiškūnaitė

    2016-11-01

    Full Text Available Currently, different methods for air clean-up from chemical pollutants are applied worldwide: adsorption, absorption, and thermal and catalytic oxidation. One of the most promising methods is biological air cleaning. The aim of this study was to test the performance of a developed biofilter with packing material of activated pine bark for biological air cleaning and to mathematically model the biofiltration processes. Comparative analysis of the modelling results for individual pollutants (butyl acetate, butanol and xylene showed strongest dependence of the efficiency of xylene removal from the air on the amount and ratio of other substances (from 20% to 70%. Thus, the process of removal of pollutants (butanol and butyl acetate that are easier to biologically decompose was obtained to be influenced to a lesser extent by the amount and ratio (% of other components. The results also showed that the efficiency of butyl acetate removal mostly depended on the ratio of other substances in the mixture (from 15% to 100%, whereas the efficiency of butyl acetate and xylene removal mostly depended on the amount of other substances in the mixture (from 20% to 100%. With the parameters of the biofilter (height of packing material, incoming air flow velocity and the pollutants to be removed known, the mathematical expression of the filter efficiency was found, which would allow to make theoretical calculation and selection of the most appropriate parameters of the device as well as to achieve maximum efficiency of air cleaning.

  2. Recovering entanglement by local operations

    Energy Technology Data Exchange (ETDEWEB)

    D’Arrigo, A., E-mail: antonio.darrigo@dmfci.unict.it [CNR-IMM UOS Università (MATIS), Consiglio Nazionale delle Ricerche, Via Santa Sofia 64, 95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Università degli Studi Catania, Via Santa Sofia 64, 95123 Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia (CSFNSM), Via Santa Sofia 64, 95123 Catania (Italy); Lo Franco, R. [Dipartimento di Fisica e Chimica, Università di Palermo, via Archirafi 36, 90123 Palermo (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia (CSFNSM), Via Santa Sofia 64, 95123 Catania (Italy); Benenti, G. [CNISM and Center for Nonlinear and Complex Systems, Università degli Studi dell’Insubria, Via Valleggio 11, 22100 Como (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Paladino, E.; Falci, G. [Dipartimento di Fisica e Astronomia, Università degli Studi Catania, Via Santa Sofia 64, 95123 Catania (Italy); CNR-IMM UOS Università (MATIS), Consiglio Nazionale delle Ricerche, Via Santa Sofia 64, 95123 Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia (CSFNSM), Via Santa Sofia 64, 95123 Catania (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Catania, Viale S. Sofia 64, 95123 Catania (Italy)

    2014-11-15

    We investigate the phenomenon of bipartite entanglement revivals under purely local operations in systems subject to local and independent classical noise sources. We explain this apparent paradox in the physical ensemble description of the system state by introducing the concept of “hidden” entanglement, which indicates the amount of entanglement that cannot be exploited due to the lack of classical information on the system. For this reason this part of entanglement can be recovered without the action of non-local operations or back-transfer process. For two noninteracting qubits under a low-frequency stochastic noise, we show that entanglement can be recovered by local pulses only. We also discuss how hidden entanglement may provide new insights about entanglement revivals in non-Markovian dynamics.

  3. Optimization of the Inclusion Process of Volatile Oil from Lavandula augustifolia Mill.%薰衣草挥发油包合工艺的优化

    Institute of Scientific and Technical Information of China (English)

    何沙沙; 廉宜君; 赵文彬; 任艳艳; 慕永歌; 陈韩英

    2011-01-01

    [目的] 优化薰衣草挥发油超声包合工艺,为薰衣草挥发油制剂的开发研究提供试验依据.[方法]以挥发油利用率为考察指标,采用单因素试验对薰衣草挥发油包合前溶解的乙醇浓度、乙醇用量进行考察;采用正交试验设计对薰衣草挥发油包合过程中各工艺参数进行优选.[结果] 薰衣草挥发油最佳包合工艺:挥发油用85%乙醇按1:25 的比例溶解,油:B-CD值为1:10,β-CD 浓度为12%,包合温度为55℃,超声包结时间为2.0 h.在最佳工艺条件下,薰衣草挥发油的利用率达到87.63%.[结论]该试验得到的包合工艺挥发油利用率高,操作简便,为薰衣草挥发油制剂的开发提供了试验依据.%[Objective] To optimize the inclusion process of Lavandula augustifolia Mill. volatile oil,so as to provide experimental basis for the developing and study of essential oil preparation products from Lavandula augustifolia Mill.. [ Method] Using utilization rate of volatile oil as an indicator,the concentration and use amount of ethanol employed to dissolve Lavandula augustifolia Mill. volatile oil were optimized by single factor test, and the inclusion process parameters were optimized by orthogonal test. [ Result ] With the proportion of 1:25,85% ethanol was used to dissolve the volatile oil. The optimum inclusion conditions for lavender volatile oil were as follows:ratio of essential oil to β-CD of 1: 10, β-CD concentration of 12% ,inclusion temperature of 55 ℃ and ultrasonic inclusion duration of 2.0 hours. Under the optimal inclusion process,the use rate of Lavandula augustifolia Mill. volatile oil reached as high as 87.63%. [ Conclusion] Simple in operation ,the inclusion process for Lavandula augustifolia Mill. volatile oil was high in utilization ratio,which provided experimental basis for the developing and study of essential oil preparation products from Lavandula augustifolia Mill.

  4. Phytoremediation of 1,4-dioxane-containing recovered groundwater.

    Science.gov (United States)

    Ferro, Ari M; Kennedy, Jean; LaRue, James C

    2013-01-01

    The results of a pilot-scale phytoremediation study are reported in this paper. Small plots of trees established on a closed municipal waste landfill site were irrigated with recovered groundwater containing 1,4-dioxane (dioxane) and other volatile organic compounds (VOCs). The plots were managed to minimize the leaching of irrigation water, and leaching was quantified by the use of bromide tracer. Results indicated that the dioxane (2.5 microg/L) was effectively removed, probably via phytovolatilization, and that a full-scale phytoremediation system could be used. A system is now in place at the site in which the recovered groundwater can be treated using two different approaches. A physical treatment system (PTS) will be used during the winter months, and a 12 ha phytoremediation system (stands of coniferous trees) will be used during the growing season. The PTS removes VOCs using an air-stripper, and destroys dioxane using a photo-catalytic oxidation process. Treated water will be routed to the local sewer system. The phytoremediation system, located on the landfill, will be irrigated with effluent from the PTS air-stripper containing dioxane. Seasonal use of the phytoremediation system will reduce reliance on the photo-catalytic oxidation process that is extremely energy consumptive and expensive to operate.

  5. Recent Advances in Volatiles of Teas

    Directory of Open Access Journals (Sweden)

    Xin-Qiang Zheng

    2016-03-01

    Full Text Available Volatile compounds are important components of tea aroma, a key attribute of sensory quality. The present review examines the formation of aromatic volatiles of various kinds of teas and factors influencing the formation of tea volatiles, including tea cultivar, growing environment and agronomic practices, processing method and storage of tea. The determination of tea volatiles and the relationship of active-aroma volatiles with the sensory qualities of tea are also discussed in the present paper.

  6. Chasing volatility

    DEFF Research Database (Denmark)

    Caporin, Massimiliano; Rossi, Eduardo; Santucci de Magistris, Paolo

    The realized volatility of financial returns is characterized by persistence and occurrence of unpreditable large increments. To capture those features, we introduce the Multiplicative Error Model with jumps (MEM-J). When a jump component is included in the multiplicative specification, the condi...... models, the introduction of the jump component provides a sensible improvement in the fit, as well as for in-sample and out-of-sample volatility tail forecasts....

  7. Volatility Risk

    OpenAIRE

    Zhiguang Wang

    2009-01-01

    Classical capital asset pricing theory tells us that riskaverse investors would require higher returns to compensate for higher risk on an investment. One type of risk is price (return) risk, which reflects uncertainty in the price level and is measured by the volatility (standard deviation) of asset returns. Volatility itself is also known to be random and hence is perceived as another type of risk. Investors can bear price risk in exchange for a higher return. But are investors willing to p...

  8. PERBEDAAN KANDUNGAN SENYAWA VOLATIL DAUN SALAM (Eugenia polyantha Wight) PADA BEBERAPA PROSES CURING The Difference of Volatile Compounds of Bay Leaf (Eugenia polyantha Wight.) in Several Curing Processes

    OpenAIRE

    2012-01-01

    The influence of curing process toward flavour substances of bay leaf has been conducted. Bay leaves were cured with three different time of process: 0, 2 and 4 days and extracted by simultaneous distillation-extraction using n- hexane. Flavour extract was evaporated by vacuum rotary evaporator and remained solvent was flushed with nitrogen gas. Flavour compounds of the bay leaf extract were analysed using GC-MS. The result showed that curing process affected the composition of bay leaf flavo...

  9. Evaluation of volatile profiles obtained for minimally-processed pineapple fruit samples during storage by headspace-solid phase microextraction gas chromatography-mass spectrometry

    Directory of Open Access Journals (Sweden)

    Francielle Crocetta TURAZZI

    Full Text Available Abstract This paper describes the application of the solid-phase microextraction (SPME technique for the determination and monitoring of the volatile profile of minimally-processed pineapple fruit stored at various temperatures (-12 °C, 4 °C and 25 °C for different periods (1, 4 and 10 days. The SPME fiber coating composed of Car/PDMS presented the best performance. The optimal extraction conditions obtained through a Doehlert design were 60 min at 35 °C. The profiles for the volatile compounds content of the fruit at each stage of storage were determined by gas chromatography-mass spectrometry (GC-MS. The variation in the volatile profile over time was greater when the fruit samples were stored at 25 °C and at -12 °C compared to 4 °C. Thus, according to the volatile profiles associated with the storage conditions evaluated in this study, packaged pineapple retains best its fresh fruit aroma when stored at 4 °C.

  10. 小青龙贴中挥发油的提取工艺研究%Study on the Extraction Process of Volatile Oil in Xiaoqinglong Plaster

    Institute of Scientific and Technical Information of China (English)

    徐志红; 陈磊垚; 刘欣怡

    2013-01-01

    Objective To optimize the best conditions of the extraction process of volatile oil in xi-aoqinglong plaster. Methods L9( 34 ) orthogonal test was adopted. The extraction rate of volatile oil was taken as the observation index. It was to observe the impacts of water amount, soak time and extraction time on the extraction rate of volatile ole in xiaoqinglong plaster. Results The extraction and soak time brought the best impact on the extraction of volatile oil, presenting the best significance. The water volume impacted less on the results. In consideration with the actual production, the final decision of the extraction process of volatile oil in xiaoqinglong plaster was: adding water 8 times as the weight of herbal materials, soaking for 1 h, steam distillation for 6 h. Conclusion In the verification test, the extraction rate of xiaoqinglong plaster of 3 batches is stable; the optimized extraction process of volatile oil is simple,stable and feasible. This process is suitable to be applied in the industrialized production.%目的 优选小青龙贴中挥发油的最佳提取工艺条件.方法 采用L9(34)正交试验方法,以得油率为考察指标,考察加水量、浸泡时间和提取时间三个因素对小青龙贴中得油率的影响.结果 提取时间和浸泡时间对提取挥发油的影响最大,最有显著性意义,加水量对结果的影响较小.结合实际生产,最终确定小青龙贴中挥发油的提取工艺为:药材加8倍量水,浸泡1 h,水蒸气蒸馏6 h.结论 验证试验中三批小青龙贴得油率稳定,所优选的挥发油提取工艺简单、稳定、可行,适用于工业化大生产.

  11. Development of Voloxidation Process for Treatment of LWR Spent Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Park, J. J.; Jung, I. H.; Shin, J. M. (and others)

    2007-08-15

    The objective of the project is to develop a process which provides a means to recover fuel from the cladding, and to simplify downstream processes by recovering volatile fission products. This work focuses on the process development in three areas ; the measurement and assessment of the release behavior for the volatile and semi-volatile fission products from the voloxidation process, the assessment of techniques to trap and recover gaseous fission products, and the development of process cycles to optimize fuel cladding separation and fuel particle size. High temperature adsorption method of KAERI was adopted in the co-design of OTS for hot experiment in INL. KAERI supplied 6 sets of filter for hot experiment. Three hot experiment in INL hot cell from the 25th of November for two weeks with attaching 4 KAERI staffs had been carried out. The results were promising. For example, trapping efficiency of Cs was 95% and that of I was 99%, etc.

  12. A Fractionally Integrated Wishart Stochastic Volatility Model

    NARCIS (Netherlands)

    M. Asai (Manabu); M.J. McAleer (Michael)

    2013-01-01

    textabstractThere has recently been growing interest in modeling and estimating alternative continuous time multivariate stochastic volatility models. We propose a continuous time fractionally integrated Wishart stochastic volatility (FIWSV) process. We derive the conditional Laplace transform of

  13. Process qualification strategy for advances embedded non volatile memory technology - the Philips'0.18um embedded flash case

    NARCIS (Netherlands)

    Tao, Guoqiao; Scarpa, Andrea; Dijk, van Kitty; Kuper, Fred G.

    2003-01-01

    A qualification strategy for advanced embedded non-volatile memory technology has been revealed. This strategy consists of: a thorough understanding of the requirements, extensive use and frequent update of the FMEA (failure mode effect analysis), a qualification plan with excellent coverage of all

  14. METHOD OF RECOVERING THORIUM

    Science.gov (United States)

    Fisher, R.W.

    1957-12-10

    A method is described for recovering thorium from impurities found in a slag containing thorium and said impurities, comprising leaching a composition containing thorium with water, removing the water solution, treating the residue with hydrochloric acid, separating the solution from the insoluble residue, adjusting its acidity to 1 to 3 normal, adding oxalic acid, and thereafter separating the precipitated thorium oxalate digesting the residue from the hydrochloric acid treatment with a strong solution of sodium hydroxide at an elevated temperature, removing said solution and treating the insoluble residue with hydrochloric acid, separating the solution from the insoluble residue, adjusting the acidity of this solution to 1 to 3 normal, adding nitric acid to oxidize the iron present, adding oxalic acid and thereafter separating the thorium oxalate thus precipitated.

  15. Stochastic volatility selected readings

    CERN Document Server

    Shephard, Neil

    2005-01-01

    Neil Shephard has brought together a set of classic and central papers that have contributed to our understanding of financial volatility. They cover stocks, bonds and currencies and range from 1973 up to 2001. Shephard, a leading researcher in the field, provides a substantial introduction in which he discusses all major issues involved. General Introduction N. Shephard. Part I: Model Building. 1. A Subordinated Stochastic Process Model with Finite Variance for Speculative Prices, (P. K. Clark). 2. Financial Returns Modelled by the Product of Two Stochastic Processes: A Study of Daily Sugar Prices, 1961-7, S. J. Taylor. 3. The Behavior of Random Variables with Nonstationary Variance and the Distribution of Security Prices, B. Rosenberg. 4. The Pricing of Options on Assets with Stochastic Volatilities, J. Hull and A. White. 5. The Dynamics of Exchange Rate Volatility: A Multivariate Latent Factor ARCH Model, F. X. Diebold and M. Nerlove. 6. Multivariate Stochastic Variance Models. 7. Stochastic Autoregressive...

  16. Flash Thermal Conditioning of Olive Pastes during the Oil Mechanical Extraction Process: Cultivar Impact on the Phenolic and Volatile Composition of Virgin Olive Oil.

    Science.gov (United States)

    Veneziani, Gianluca; Esposto, Sonia; Taticchi, Agnese; Selvaggini, Roberto; Urbani, Stefania; Di Maio, Ilona; Sordini, Beatrice; Servili, Maurizio

    2015-07-08

    The concentration of phenolic and volatile compounds in virgin olive oil (VOO) is closely related to the different operative conditions applied to the mechanical extraction process of the olive oil. However, the great qualitative and quantitative variability of these compounds indicates an important role played by genetic and agronomic aspects. A heat exchanger was placed in front of a traditional, covered malaxer to study the impact of flash thermal conditioning (FTC) of olive paste on the quality of VOO, which is highly influenced by phenolic release and aroma generation. The VOO flash thermal conditioning of five major Italian cultivars showed a higher concentration of phenols (range of increase percentage, 9.9-37.3%) compared to the control trials, whereas the FTC treatment featured a differentiated impact on the volatile fractions, associated with the genetic origins of the olives.

  17. Volatiles in protoplanetary disks

    CERN Document Server

    Pontoppidan, Klaus M; Bergin, Edwin A; Brittain, Sean; Marty, Bernard; Mousis, Olvier; Oberg, Karin L

    2014-01-01

    Volatiles are compounds with low sublimation temperatures, and they make up most of the condensible mass in typical planet-forming environments. They consist of relatively small, often hydrogenated, molecules based on the abundant elements carbon, nitrogen and oxygen. Volatiles are central to the process of planet formation, forming the backbone of a rich chemistry that sets the initial conditions for the formation of planetary atmospheres, and act as a solid mass reservoir catalyzing the formation of planets and planetesimals. This growth has been driven by rapid advances in observations and models of protoplanetary disks, and by a deepening understanding of the cosmochemistry of the solar system. Indeed, it is only in the past few years that representative samples of molecules have been discovered in great abundance throughout protoplanetary disks - enough to begin building a complete budget for the most abundant elements after hydrogen and helium. The spatial distributions of key volatiles are being mapped...

  18. In-cloud processes of methacrolein under simulated conditions – Part 3: Hygroscopic and volatility properties of the formed secondary organic aerosol

    Directory of Open Access Journals (Sweden)

    A. Monod

    2009-07-01

    Full Text Available The hygroscopic and volatility properties of secondary organic aerosol (SOA produced from the nebulization of solutions after aqueous phase photooxidation of methacrolein was experimentally studied in a laboratory, using a Volatility-Hygroscopicity Tandem DMA (VHTDMA. The obtained SOA were 80% 100°C-volatile after 5 h of reaction and only 20% 100°C-volatile after 22 h of reaction. The Hygroscopic Growth Factor (HGF of the SOA produced from the nebulization of solutions after aqueous-phase photooxidation of methacrolein is 1.34–1.43, which is significantly higher than the HGF of SOA formed by gas-phase photooxidation of terpenes, usually found almost hydrophobic. These hygroscopic properties were confirmed for SOA formed by the nebulization of the same solutions where NaCl was added. The hygroscopic properties of the cloud droplet residuals decrease with the reaction time, in parallel with the formation of more refractory compounds. This decrease was mainly attributed to the 250°C-refractive fraction (presumably representative of the highest molecular weight compounds, which evolved from moderately hygroscopic (HGF of 1.52 to less hygroscopic (HGF of 1.36. Oligomerization is suggested as a process responsible for the decrease of both volatility and hygroscopicity with time. The NaCl seeded experiments enabled us to show that 19±4 mg L−1 of SOA was produced after 9.5 h of reaction and 41±9 mg L−1 after 22 h of in-cloud reaction. Because more and more SOA is formed as the reaction time increases, our results show that the reaction products formed during the aqueous-phase OH-oxidation of methacrolein may play a major role in the properties of residual particles upon the droplet's evaporation. Therefore, the specific physical properties of SOA produced during cloud processes should be taken into account for a global estimation of SOA and their atmospheric impacts.

  19. Volatile phenols depletion in red wine using molecular imprinted polymers.

    Science.gov (United States)

    Teixeira, Rafaela; Dopico-García, Sonia; Andrade, Paula B; Valentão, Patrícia; López-Vilariño, José M; González-Rodríguez, Victoria; Cela-Pérez, Concepción; Silva, Luís R

    2015-12-01

    Wines can be modified by microorganisms during the ageing process, by producing off-flavours like volatile phenols (VP), leading to their deterioration, with great economic losses. The development of methods to recover wines affected by unwanted VP became an important target. Molecular imprinted polymers (MIPs) are synthetic materials with artificially-generated recognition sites for selective extraction of organic compounds from different matrices. In this work, two MIPs to remove unwanted VP from wines were developed and their effects were evaluated. Volatile compounds were determined by GC-FID and GC-IT/MS and phenolic compounds (non-coloured and anthocyanins) by HPLC-DAD. The treatment with MIP-4EG and MIP-4EP significantly reduced the content of 4-ethylguaiacol and 4-ethylphenol, respectively. Nevertheless, the changes observed in wine non-coloured and coloured phenolics and sensorial analysis indicate that their specificity and selectivity regarding off-flavours still needs to be improved.

  20. Ammonia volatilization from intensively managed dairy pastures.

    NARCIS (Netherlands)

    Bussink, D.W.

    1996-01-01

    The objectives of this thesis are (i) to quantify NH 3 volatilization from grassland, (ii) to gain understanding of the NH3 volatilization processes on grassland and (iii) to study measures how to reduce NH 3 volatilization from gra

  1. Applications for carbon fibre recovered from composites

    Science.gov (United States)

    Pickering; Liu, Z.; Turner, TA; Wong, KH

    2016-07-01

    Commercial operations to recover carbon fibre from waste composites are now developing and as more recovered fibre becomes available new applications for recovered fibre are required. Opportunities to use recovered carbon fibre as a structural reinforcement are considered involving the use of wet lay processes to produce nonwoven mats. Mats with random in-plane fibre orientation can readily be produced using existing commercial processes. However, the fibre volume fraction, and hence the mechanical properties that can be achieved, result in composites with limited mechanical properties. Fibre volume fractions of 40% can be achieved with high moulding pressures of over 100 bar, however, moulding at these pressures results in substantial fibre breakage which reduces the mean fibre length and the properties of the composite manufactured. Nonwoven mats made from aligned, short carbon fibres can achieve higher fibre volume fractions with lower fibre breakage even at high moulding pressure. A process for aligning short fibres is described and a composite of over 60% fibre volume fraction has been manufactured at a pressures up to 100 bar with low fibre breakage. Further developments of the alignment process have been undertaken and a composite of 46% fibre volume fraction has been produced moulded at a pressure of 7 bar in an autoclave, exhibiting good mechanical properties that compete with higher grade materials. This demonstrates the potential for high value applications for recovered carbon fibre by fibre alignment.

  2. CYCLODEXTRINS TO RECOVER TEXTILE DYES IN WASTE WATER

    Directory of Open Access Journals (Sweden)

    FRANCO Esther

    2015-05-01

    Full Text Available Cyclodextrins are cyclic oligosaccharides with a special toroid shape, obtained by the action of glucosyltransferase enzyme (CGTase on starch molecule. Their peculiar structure allows the accommodation of different guest molecules inside their cavity forming molecular inclusion complexes. There are different types depending on the glucose units that are formed, called native. The cyclodextrins can be modified incorporating different groups (hydroxipropyl, methyl... that changes their properties. Due their versatility in size, properties and the variety of inclusion complex can form is employed in many different industries like pharmacy, food or cosmetics to protect the molecule or to reduce their volatility. As the guest molecule is not bond with the cyclodextrin with the appropriate conditions it can release easily. In textile industry had been use in different areas: to remove surfactants from washed textiles, to substitute surfactants, in the dyeing process, in detergents… Due their capacity to fix onto textile allows the functionalization of the fabrics giving them new properties like UV protection, antimicrobial or insect repellents depending on the guest molecule, in. The project DYES4EVER employs the cyclodextrins to encapsulate dyes not fixed during the dye process that remains in the wastewater and aims to go one step further and reuse the dyes recovered as a raw material in new dyeing processes.

  3. Exponential Smoothing, Long Memory and Volatility Prediction

    DEFF Research Database (Denmark)

    Proietti, Tommaso

    Extracting and forecasting the volatility of financial markets is an important empirical problem. The paper provides a time series characterization of the volatility components arising when the volatility process is fractionally integrated, and proposes a new predictor that can be seen as extensi...... methods for forecasting realized volatility, and that the estimated model confidence sets include the newly proposed fractional lag predictor in all occurrences....

  4. Process of separating and recovering flare gas from petrochemical plant via hydrate formation%水合物法分离回收石油化工厂火炬气工艺研究

    Institute of Scientific and Technical Information of China (English)

    王海秀; 周锡堂

    2013-01-01

    介绍了4种火炬气回收工艺和水合物法气体分离技术,提出了水合物法分离回收石油化工厂火炬气的新工艺——利用水合物的生成逐一分离、回收其中有价值的组分.对流程的特点和技术可行性进行了分析,指出对于组分复杂的火炬气可采用水合物法分离回收.与传统工艺相比,该工艺具有回收彻底、更节能、更环保等诸多优点.%Four flare gas recovery process and gas separation technology via forming hydrate are introduced.A novel process for separating and recovering flare gas from petrochemical plant by hydrate formation is proposed.Each component can be separated by forming hydrate and the valuable composition is recovered.The characteristics and technical feasibility are analysed.For flare gas of complex constituents,the gas separation and recovery technology via forming hydrate is recommended.Compared with the traditional process,the novel process has the advantages of complete recovery,energy saving and environmental protection.

  5. Recovering probabilities for nucleotide trimming processes for T cell receptor TRA and TRG V-J junctions analyzed with IMGT tools.

    Science.gov (United States)

    Bleakley, Kevin; Lefranc, Marie-Paule; Biau, Gérard

    2008-10-02

    Nucleotides are trimmed from the ends of variable (V), diversity (D) and joining (J) genes during immunoglobulin (IG) and T cell receptor (TR) rearrangements in B cells and T cells of the immune system. This trimming is followed by addition of nucleotides at random, forming the N regions (N for nucleotides) of the V-J and V-D-J junctions. These processes are crucial for creating diversity in the immune response since the number of trimmed nucleotides and the number of added nucleotides vary in each B or T cell. IMGT sequence analysis tools, IMGT/V-QUEST and IMGT/JunctionAnalysis, are able to provide detailed and accurate analysis of the final observed junction nucleotide sequences (tool "output"). However, as trimmed nucleotides can potentially be replaced by identical N region nucleotides during the process, the observed "output" represents a biased estimate of the "true trimming process." A probabilistic approach based on an analysis of the standardized tool "output" is proposed to infer the probability distribution of the "true trimmming process" and to provide plausible biological hypotheses explaining this process. We collated a benchmark dataset of TR alpha (TRA) and TR gamma (TRG) V-J rearranged sequences and junctions analysed with IMGT/V-QUEST and IMGT/JunctionAnalysis, the nucleotide sequence analysis tools from IMGT, the international ImMunoGeneTics information system, http://imgt.cines.fr. The standardized description of the tool output is based on the IMGT-ONTOLOGY axioms and concepts. We propose a simple first-order model that attempts to transform the observed "output" probability distribution into an estimate closer to the "true trimming process" probability distribution. We use this estimate to test the hypothesis that Poisson processes are involved in trimming. This hypothesis was not rejected at standard confidence levels for three of the four trimming processes: TRAV, TRAJ and TRGV. By using trimming of rearranged TR genes as a benchmark, we

  6. Recovering probabilities for nucleotide trimming processes for T cell receptor TRA and TRG V-J junctions analyzed with IMGT tools

    Directory of Open Access Journals (Sweden)

    Lefranc Marie-Paule

    2008-10-01

    Full Text Available Abstract Background Nucleotides are trimmed from the ends of variable (V, diversity (D and joining (J genes during immunoglobulin (IG and T cell receptor (TR rearrangements in B cells and T cells of the immune system. This trimming is followed by addition of nucleotides at random, forming the N regions (N for nucleotides of the V-J and V-D-J junctions. These processes are crucial for creating diversity in the immune response since the number of trimmed nucleotides and the number of added nucleotides vary in each B or T cell. IMGT® sequence analysis tools, IMGT/V-QUEST and IMGT/JunctionAnalysis, are able to provide detailed and accurate analysis of the final observed junction nucleotide sequences (tool "output". However, as trimmed nucleotides can potentially be replaced by identical N region nucleotides during the process, the observed "output" represents a biased estimate of the "true trimming process." Results A probabilistic approach based on an analysis of the standardized tool "output" is proposed to infer the probability distribution of the "true trimmming process" and to provide plausible biological hypotheses explaining this process. We collated a benchmark dataset of TR alpha (TRA and TR gamma (TRG V-J rearranged sequences and junctions analysed with IMGT/V-QUEST and IMGT/JunctionAnalysis, the nucleotide sequence analysis tools from IMGT®, the international ImMunoGeneTics information system®, http://imgt.cines.fr. The standardized description of the tool output is based on the IMGT-ONTOLOGY axioms and concepts. We propose a simple first-order model that attempts to transform the observed "output" probability distribution into an estimate closer to the "true trimming process" probability distribution. We use this estimate to test the hypothesis that Poisson processes are involved in trimming. This hypothesis was not rejected at standard confidence levels for three of the four trimming processes: TRAV, TRAJ and TRGV. Conclusion By

  7. Proposal and design of a natural gas liquefaction process recovering the energy obtained from the pressure reducing stations of high-pressure pipelines

    Science.gov (United States)

    Tan, Hongbo; Zhao, Qingxuan; Sun, Nannan; Li, Yanzhong

    2016-12-01

    Taking advantage of the refrigerating effect in the expansion at an appropriate temperature, a fraction of high-pressure natural gas transported by pipelines could be liquefied in a city gate station through a well-organized pressure reducing process without consuming any extra energy. The authors proposed such a new process, which mainly consists of a turbo-expander driven booster, throttle valves, multi-stream heat exchangers and separators, to yield liquefied natural gas (LNG) and liquid light hydrocarbons (LLHs) utilizing the high-pressure of the pipelines. Based on the assessment of the effects of several key parameters on the system performance by a steady-state simulation in Aspen HYSYS, an optimal design condition of the proposed process was determined. The results showed that the new process is more appropriate to be applied in a pressure reducing station (PRS) for the pipelines with higher pressure. For the feed gas at the pressure of 10 MPa, the maximum total liquefaction rate (ytot) of 15.4% and the maximum exergy utilizing rate (EUR) of 21.7% could be reached at the optimal condition. The present process could be used as a small-scale natural gas liquefying and peak-shaving plant at a city gate station.

  8. Modelling and Predicting the Breaking Strength and Mass Irregularity of Cotton Rotor-Spun Yarns Containing Cotton Fiber Recovered from Ginning Process by Using Artificial Neural Network Algorithm

    Directory of Open Access Journals (Sweden)

    Mohsen Shanbeh

    2011-01-01

    Full Text Available One of the main methods to reduce the production costs is waste recycling which is the most important challenge for the future. Cotton wastes collected from ginning process have desirable properties which could be used during spinning process. The purpose of this study was to develop predictive models of breaking strength and mass irregularity (CV% of cotton waste rotor-spun yarns containing cotton waste collected from ginning process by using the artificial neural network trained with backpropagation algorithm. Artificial neural network models have been developed based on rotor diameter, rotor speed, navel type, opener roller speed, ginning waste proportion and yarn linear density as input parameters. The parameters of artificial neural network model, namely, learning, and momentum rate, number of hidden layers and number of hidden processing elements (neurons were optimized to get the best predictive models. The findings showed that the breaking strength and mass irregularity of rotor spun yarns could be predicted satisfactorily by artificial neural network. The maximum error in predicting the breaking strength and mass irregularity of testing data was 8.34% and 6.65%, respectively.

  9. Subtyping of Listeria monocytogenes isolates recovered from retail ready-to-eat foods, processing plants and listeriosis patients in Sweden 2010.

    Science.gov (United States)

    Lambertz, S Thisted; Ivarsson, S; Lopez-Valladares, G; Sidstedt, M; Lindqvist, R

    2013-08-16

    Identification and prioritisation of food safety interventions requires an understanding of the relationship between food, pathogens and cases. Such understanding can be gained through different approaches, e.g. microbial subtyping to attribute cases of foodborne disease to food vehicles or other sources of illness. In this study, Listeria monocytogenes isolates (n=166) from (i) three categories of ready-to-eat (RTE) foods, (ii) food processing plant environments, and (iii) human listeriosis cases, all sampled during 2010 in Sweden, were subtyped. In addition, 121 isolates from human listeriosis cases, collected 2005-2009, were subtyped. Subtyping consisted of both serotyping (conventional method and PCR) and genotyping using pulsed-field gel electrophoresis (PFGE). Serotype 1/2a dominated in all three groups of isolates (range 73-96%). Eighteen percent of the human isolates (2010) belonged to serotype 4b, but only 1.4% of the food isolates. The food isolates differentiated into 19 pulsotypes (ID=0.843), the human isolates collected 2010 into 31 pulsotypes (ID=0.950) and the processing plant isolates into 22 pulsotypes (ID=0.991). Six of the pulsotypes were shared between the food and human isolates. These pulsotypes comprised 42% of the human isolates and 59% of the food isolates. For some processing plants, there was suggested persistence of one or more specific L. monocytogenes strains, as indicated by repetitive isolation of the same pulsotype from food. This study indicated the presence of L. monocytogenes in the processing plant environment as a likely source of contamination of gravad and cold-smoked fish, and this food category as an important source of human exposure to the pathogen.

  10. Stochastic volatility and stochastic leverage

    DEFF Research Database (Denmark)

    Veraart, Almut; Veraart, Luitgard A. M.

    This paper proposes the new concept of stochastic leverage in stochastic volatility models. Stochastic leverage refers to a stochastic process which replaces the classical constant correlation parameter between the asset return and the stochastic volatility process. We provide a systematic...... treatment of stochastic leverage and propose to model the stochastic leverage effect explicitly, e.g. by means of a linear transformation of a Jacobi process. Such models are both analytically tractable and allow for a direct economic interpretation. In particular, we propose two new stochastic volatility...... models which allow for a stochastic leverage effect: the generalised Heston model and the generalised Barndorff-Nielsen & Shephard model. We investigate the impact of a stochastic leverage effect in the risk neutral world by focusing on implied volatilities generated by option prices derived from our new...

  11. Pricing Volatility Referenced Assets

    Directory of Open Access Journals (Sweden)

    Alan De Genaro Dario

    2006-12-01

    Full Text Available Volatility swaps are contingent claims on future realized volatility. Variance swaps are similar instruments on future realized variance, the square of future realized volatility. Unlike a plain vanilla option, whose volatility exposure is contaminated by its asset price dependence, volatility and variance swaps provide a pure exposure to volatility alone. This article discusses the risk-neutral valuation of volatility and variance swaps based on the framework outlined in the Heston (1993 stochastic volatility model. Additionally, the Heston (1993 model is calibrated for foreign currency options traded at BMF and its parameters are used to price swaps on volatility and variance of the BRL / USD exchange rate.

  12. Recovering Seasat SAR Data

    Science.gov (United States)

    Logan, T. A.; Arko, S. A.; Rosen, P. A.

    2013-12-01

    To demonstrate the feasibility of orbital remote sensing for global ocean observations, NASA launched Seasat on June 27th, 1978. Being the first space borne SAR mission, Seasat produced the most detailed SAR images of Earth from space ever seen to that point in time. While much of the data collected in the USA was processed optically, a mere 150 scenes had been digitally processed by March 1980. In fact, only an estimated 3% of Seasat data was ever digitally processed. Thus, for over three decades, the majority of the SAR data from this historic mission has been dormant, virtually unavailable to scientists in the 21st century. Over the last year, researchers at the Alaska Satellite Facility (ASF) Distributed Active Archive Center (DAAC) have processed the Seasat SAR archives into imagery products. A telemetry decoding system was created and the data were filtered into readily processable signal files. Due to nearly 35 years of bit rot, the bit error rate (BER) for the ASF DAAC Seasat archives was on the order of 1 out of 100 to 1 out of 100,000. This extremely high BER initially seemed to make much of the data undecodable - because the minor frame numbers are just 7 bits and no range line numbers exist in the telemetry even the 'simple' tasks of tracking the minor frame number or locating the start of each range line proved difficult. Eventually, using 5 frame numbers in sequence and a handful of heuristics, the data were successfully decoded into full range lines. Concurrently, all metadata were stored into external files. Recovery of this metadata was also problematic, the BER making the information highly suspect and, initially at least, unusable in any sort of automated fashion. Because of the BER, all of the single bit metadata fields proved unreliable. Even fields that should be constant for a data take (e.g. receiving station, day of the year) showed high variability, each requiring a median filter to be usable. The most challenging, however, were the

  13. Capture and identification of the volatile components in crude and processed herbal medicines through on-line purge and trap technique coupled with GC × GC-TOF MS.

    Science.gov (United States)

    Cao, Gang; Xu, Zhiwei; Wu, Xin; Li, Qingli; Chen, Xiaocheng

    2014-01-01

    This work aimed to investigate the volatile components in crude and processed herbal medicines (HMs). Using Atractylodis Macrocephalae Rhizoma (AMR) as a model HM, the volatile components were captured through on-line purge and trap technique and identified by using comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOF MS) system. A total of 224 and 171 volatile compounds were identified in crude and processed AMR samples, respectively. After frying with honey-bran, 52 compounds which were found in crude AMR samples disappeared in processed AMR samples, and 15 compounds were newly generated in processed AMR. The established method can be applied in different research areas such as HM and food processing.

  14. Studies on mathematical modeling of the leaching process in order to efficiently recover lead from the sulfate/oxide lead paste.

    Science.gov (United States)

    Buzatu, Traian; Ghica, Gabriel Valeriu; Petrescu, Ionuţ Mircea; Iacob, Gheorghe; Buzatu, Mihai; Niculescu, Florentina

    2017-02-01

    Increasing global lead consumption has been mainly supported by the acid battery manufacturing industry. As the lead demand will continue to grow, to provide the necessary lead will require an efficient approach to recycling lead acid batteries. In this paper was performed a mathematical modeling of the process parameters for lead recovery from spent lead-acid batteries. The results of the mathematical modeling compare well with the experimental data. The experimental method applied consists in the solubilisation of the sulfate/oxide paste with sodium hydroxide solutions followed by electrolytic processing for lead recovery. The parameters taken into considerations were NaOH molarity (4M, 6M and 8M), solid/liquid ratio - S/L (1/10, 1/30 and 1/50) and temperature (40°C, 60°C and 80°C). The optimal conditions resulted by mathematical modeling of the electrolytic process of lead deposition from alkaline solutions have been established by using a second-order orthogonal program, in order to obtain a maximum efficiency of current without exceeding an imposed energy specific consumption. The optimum value for the leaching recovery efficiency, obtained through mathematical modeling, was 89.647%, with an error of δy=3.623 which leads to a maximum recovery efficiency of 86.024%. The optimum values for each variable that ensure the lead extraction efficiency equal to 89.647% are the following: 3M - NaOH, 1/35 - S/L, 70°C - temperature. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Mathematical modeling of the whole expanded bed adsorption process to recover and purify chitosanases from the unclarified fermentation broth of Paenibacillus ehimensis.

    Science.gov (United States)

    de Araújo Padilha, Carlos Eduardo; Fortunato Dantas, Paulo Victor; de Sousa, Francisco Canindé; de Santana Souza, Domingos Fabiano; de Oliveira, Jackson Araújo; de Macedo, Gorete Ribeiro; Dos Santos, Everaldo Silvino

    2016-12-15

    In this study, a general rate model was applied to the entire process of expanded bed adsorption chromatography (EBAC) for the chitosanases purification protocol from unclarified fermentation broth produced by Paenibacillus ehimensis using the anionic adsorbent Streamline(®) DEAE. For the experiments performed using the expanded bed, a homemade column (2.6cm×30.0cm) was specially designed. The proposed model predicted the entire EBA process adequately, giving R(2) values higher than 0.85 and χ(2) as low as 0.351 for the elution step. Using the validated model, a 3(3) factorial design was used to investigate other non-tested conditions as input. It was observed that the superficial velocity during loading and washing steps, as well as the settled bed height, has a strong positive effect on the F objective function used to evaluate the production of the purified chitosanases. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Study on Technology Process of Recovering Scheelite from Tailings%从尾矿中回收白钨矿的工艺试验研究

    Institute of Scientific and Technical Information of China (English)

    林颖; 叶志平; 吴静仪

    2014-01-01

    The process of recovery of tungsten by regrinding-flotation from an old ore tailing contained 0. 19% WO3 in the south is investigated. The results show that satisfactory flotation indexes can be achieved by the process of one stage roughing,two-stage scavenging and three-stage cleaning,with sodium hydroxide as regulator,sodium sili-cate as the depressant and paraffin soap oxidated 733 as the collector. The experiment of tungsten roughing shows that the optimized dosage of NaOH is 2 000 g / t,dosage of sodium silicate is 2 000 g / t,dosage of collector 733 is 100 g / t when the optimum grinding fineness of - 0. 074 mm is 83. 52% . The tungsten concentrate grade and the recovery of WO3 reach 3. 26% and 70. 48% ,respectively. Analysis of IR spectra testified that chemisorption and bonding were the main reaction mechanism of 733 on scheelite.%研究采用再磨-浮选工艺对南方某老尾库尾矿(含 WO30.19%)中的钨进行回收.以 NaOH 为调整剂、Na2 SiO3为抑制剂、氧化石蜡皂733为捕收剂,当-0.074 mm 占83.52%的磨矿细度下,钨粗选试验最佳条件为 NaOH 用量为2000 g/ t,Na2 SiO3用量为2000 g/ t,捕收剂733用量为100 g/ t.通过一次粗选、二次扫选和三次精选流程,获得钨粗精矿含 WO33.26%,回收率为70.48%.红外光谱测定结果表明,捕收剂733对白钨矿的捕收作用以表面化学吸附和键合为主.

  17. Scaling Foreign Exchange Volatility

    OpenAIRE

    Jonathan Batten; Craig Ellis

    2001-01-01

    When asset returns are normally distributed the risk of an asset over a long return interval may be estimated by scaling the risk from shorter return intervals. While it is well known that asset returns are not normally distributed a key empirical question concerns the effect that scaling the volatility of dependent processes will have on the pricing of related financial assets. This study provides an insight into this issue by investigating the return properties of the most important currenc...

  18. A hybrid magnetic/complementary metal oxide semiconductor process design kit for the design of low-power non-volatile logic circuits

    Science.gov (United States)

    Di Pendina, G.; Prenat, G.; Dieny, B.; Torki, K.

    2012-04-01

    Since the advent of the MOS transistor, the performance of microelectronic circuits has followed Moore's law, stating that their speed and density would double every 18 months. Today, this trend tends to get out of breath: the continuously decreasing size of devices and increasing operation frequency result in power consumption and heating issues. Among the solutions investigated to circumvent these limitations, the use of non-volatile devices appears particularly promising. It allows easing, for example, the power gating technique, which consists in cutting-off the power supply of inactive blocks without losing information, drastically reducing the standby power consumption. In this approach, the advantages of magnetic tunnel junctions (MTJs) compared with other non-volatile devices allow one to design hybrid CMOS/magnetic circuits with high performance and new functionalities. Designing such circuits requires integrating MTJs in standard microelectronics design suites. This is performed by means of a process design kit (PDK) for the hybrid CMOS/magnetic technology. We present here a full magnetic PDK, which contains a compact model of the MTJ for electrical simulation, technology files for layout and physical verifications, and standard cells for the design of complex logic circuits and which is compatible with standard design suites. This PDK allows designers to accurately and comfortably design high-performance hybrid CMOS/magnetic logic circuits in the same way as standard CMOS circuits.

  19. Improvement of soluble coffee aroma using an integrated process of supercritical CO2 extraction with selective removal of the pungent volatiles by adsorption on activates carbon

    Directory of Open Access Journals (Sweden)

    S. Lucas

    2006-06-01

    Full Text Available In this paper a two-step integrated process consisting of CO2 supercritical extraction of volatile coffee compounds (the most valuable from roasted and milled coffee, and a subsequent step of selective removal of pungent volatiles by adsorption on activated carbon is presented. Some experiments were carried out with key compounds from roasted coffee aroma in order to study the adsorption step: ethyl acetate as a desirable compound and furfural as a pungent component. Operational parameters such as adsorption pressure and temperature and CO2 flowrate were optimized. Experiments were conducted at adsorption pressures of 12-17 MPa, adsorption temperatures of 35-50ºC and a solvent flow rate of 3-5 kg/h. In all cases, the solute concentration and the activated particle size were kept constant. Results show that low pressures (12 MPa, low temperatures (35ºC and low CO2 flowrates (3 kg/h are suitable for removing the undesirable pungent and smell components (e.g. furfural and retaining the desirable aroma compounds (e.g. ethyl acetate. The later operation with real roasted coffee has corroborated the previous results obtained with the key compounds.

  20. Study on a process for recovering residual liquid from production of acetic acid by carbonylation of methanol%羰基化合成醋酸过程废液的回收工艺研究

    Institute of Scientific and Technical Information of China (English)

    白芳; 华超; 迪建东

    2012-01-01

    To solve the existing difficulties in recovering and utilizing the heavy residual liquid from the production of acetic acid by carbonylation of methanol, a new process was proposed, in which first using a wiped-film evaporator to obtain the concentrated acetic acid, ethylene glycol diacetate (EGDA) and acetoxyacetic acid (AAA) distillates from the residual liquid, then the distillates were further purified by a vacuum batch distillation process to obtain the pured products. The experimental results showed that the proposed process was feasible, and the purification of the recovered products was over 99% for acetic acid and over 95% for EDGA and AAA. The effects of operation conditions were investigated, and the optimum experimental operation conditions were determined.%针对羰基化生产醋酸过程中产生的重组分残液难以回收的现状,首次提出了采用刮膜蒸发器富集醋酸废液中的醋酸、乙二醇二乙酸酯(EGDA)和乙酰氧基乙酸(AAA)馏分,其后减压间歇精馏分离富集馏分,实现羰基化醋酸废液的回收利用.试验表明该方法是切实可行的,并获得了纯度为99%以上的醋酸产品和95%以上的EGDA和AAA副产品.研究了精馏操作对EGDA和AAA纯度的影响,获得了最佳实验条件.

  1. Oenological characteristics, amino acids and volatile profiles of Hongqu rice wines during pottery storage: Effects of high hydrostatic pressure processing.

    Science.gov (United States)

    Tian, Yuting; Huang, Jiamei; Xie, Tingting; Huang, Luqiang; Zhuang, Weijin; Zheng, Yafeng; Zheng, Baodong

    2016-07-15

    Hongqu rice wines were subjected to high hydrostatic pressure (HHP) treatments of 200 MPa and 550 MPa at 25 °C for 30 min and effects on wine quality during pottery storage were examined. HHP treatment can significantly (pwines. After 18 months of storage, the HHP-treated wines exhibited a more rapid decrease in total sugars (9.3-15.3%), lower free amino acid content (e.g. lysine content decreased by 45.0-84.5%), and higher ketone content (e.g. 6- and 14-fold increase for 2-nonanone). These changes could be attributed to the occurrence of Maillard and oxidation reactions. The wines treated at 550 MPa for 30 min developed about twice as rapidly during pottery storage than untreated wines based on principal component analysis. After only 6 months, treated wines had a volatile composition and an organoleptic quality similar to that of untreated wines stored in pottery for 18 months. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Design of the extraction process for terpenes and other volatiles from allspice by solid-phase microextraction and hydrodistillation.

    Science.gov (United States)

    Bajer, Tomáš; Ligor, Magdalena; Ligor, Tomasz; Buszewski, Bogusław

    2016-02-01

    Methods for the separation and determination of terpenes (mono- and sesqui-) and phenylpropanoids such as eugenol and methyleugenol from samples of allspice berries have been developed. Chromatographic analyses of isolated groups of compounds were carried out by means of gas chromatography coupled with mass spectrometry. A comparison of various types of solid-phase microextraction fibers was performed. The highest yields of terpenes were extracted by polydimethylsiloxane and divinylbenzene/Carboxen/polydimethylsiloxane fibers (almost the same for these two fibers), approximately twice as much as by Carbowax/divinylbenzene fiber. The highest amounts of monoterpenes were extracted by divinylbenzene/Carboxen/polydimethylsiloxane fiber, and the highest amounts of sesquiterpenes were extracted by polydimethylsiloxane fiber. Moreover, the effect of water addition on extraction yields as well as time and temperature of extraction were tested. Aroma profiles of extracts obtained by solid-phase microextraction and essential oil obtained by hydrodistillation of allspice berries were compared. The aroma profile of the divinylbenzene/Carboxen/polydimethylsiloxane fiber extract was similar to the aroma profile of essential oil. Particular characteristics of volatile allspice matters were presented. The linear retention indices for each compound were calculated.

  3. Economic process to produce biohydrogen and volatile fatty acids by a mixed culture using vinasse from sugarcane ethanol industry as nutrient source.

    Science.gov (United States)

    Sydney, Eduardo Bittencourt; Larroche, Christian; Novak, Alessandra Cristine; Nouaille, Regis; Sarma, Saurabh Jyoti; Brar, Satinder Kaur; Letti, Luiz Alberto; Soccol, Vanete Thomaz; Soccol, Carlos Ricardo

    2014-05-01

    This work evaluates the potential of vinasse (a waste obtained at the bottom of sugarcane ethanol distillation columns) as nutrient source for biohydrogen and volatile fatty acids production by means of anaerobic consortia. Two different media were proposed, using sugarcane juice or molasses as carbon source. The consortium LPBAH1 was selected for fermentation of vinasse supplemented with sugarcane juice, resulting in a higher H2 yield of 7.14 molH2 molsucrose(-1) and hydrogen content in biogas of approx. 31%, while consortium LPBAH2 resulted in 3.66 molH2/molsucrose and 32.7% hydrogen content in biogas. The proposed process showed a rational and economical use for vinasse, a mandatory byproduct of the renewable Brazilian energy matrix.

  4. Multifractal diffusion entropy analysis on stock volatility in financial markets

    Science.gov (United States)

    Huang, Jingjing; Shang, Pengjian; Zhao, Xiaojun

    2012-11-01

    This paper introduces a generalized diffusion entropy analysis method to analyze long-range correlation then applies this method to stock volatility series. The method uses the techniques of the diffusion process and Rényi entropy to focus on the scaling behaviors of regular volatility and extreme volatility respectively in developed and emerging markets. It successfully distinguishes their differences where regular volatility exhibits long-range persistence while extreme volatility reveals anti-persistence.

  5. Volatile organic compound flux from manure of cattle fed diets differing in grain processing method and co-product inclusion

    Science.gov (United States)

    Hales, Kristin; Parker, David B.; Cole, N. Andy

    2015-01-01

    Odor emissions from livestock production have become increasingly important in the past decade. Odors derived from animal feeding operations are caused by odorous VOC emitted from the mixture of feces and urine, as well as feed and silage which may be experiencing microbial fermentation. Distillers grains are a by-product of corn grain fermentation used to produce fuel ethanol, and this industry has grown rapidly throughout the U.S. in past years. Therefore, the use of wet distillers grains with solubles (WDGS) in feedlot cattle diets has also increased. The objective of this research was to determine specific VOC emissions from feces and urine or a mixture of both, from cattle fed steam flaked or dry-rolled corn (DRC)-based diets containing either 0% or 30% WDGS. Flux of dimethyl trisulfide was greater from feces of cattle fed DRC than steam-flaked corn (SFC) diets. No other differences in flux from feces were detected across dietary treatments for phenol, 4-methylphenol, indole, skatole, dimethyl disulfide, and flux of volatile fatty acids (VFA) such as acetic, propionic, isobutyric, butyric, isovaleric, and valeric acids (P > 0.15). Flux of skatole, acetic acid, and valeric acid from urine was greater for cattle fed SFC than DRC diets (P acetic acid and heptanoic acid from urine was greater when cattle were fed diets containing 0% WDGS than 30% WDGS (P < 0.05). When combining urine and feces in the ratio in which they were excreted from the animal, flux of propionic acid was greater when cattle were fed DRC vs. SFC diets (P = 0.05). Based on these results, the majority of the VOC, VFA, and odor flux from cattle feeding operations is from the urine. Therefore, dietary strategies to reduce odor from cattle feeding facilities should primarily focus on reducing excretion of odorous compounds in the urine.

  6. Assessing Relative Volatility/Intermittency/Energy Dissipation

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole E.; Pakkanen, Mikko; Schmiegel, Jürgen

    We introduce the notion of relative volatility/intermittency and demonstrate how relative volatility statistics can be used to estimate consistently the temporal variation of volatility/intermittency even when the data of interest are generated by a non-semimartingale, or a Brownian semistationary...... process in particular. While this estimation method is motivated by the assessment of relative energy dissipation in empirical data of turbulence, we apply it also to energy price data. Moreover, we develop a probabilistic asymptotic theory for relative power variations of Brownian semistationary...... processes and Ito semimartingales and discuss how it can be used for inference on relative volatility/intermittency....

  7. Recirculated and Energy Recovered Linacs

    Energy Technology Data Exchange (ETDEWEB)

    Geoffrey Krafft

    2003-05-01

    Linacs that are recirculated share many characteristics with ordinary linacs, including the ability to accelerate electron beams from an injector to high energy with relatively little (normalized) emittance growth and the ability to deliver ultrashort bunch duration pulses to users. When such linacs are energy recovered, the additional possibility of accelerating very high average beam current arises. Because this combination of beam properties is not possible from either a conventional linac, or from storage rings where emittance and pulse length are set by the equilibrium between radiation damping and quantum excitation of oscillations about the closed orbit, energy recovered linacs are being considered for an increasing variety of applications. These possibilities extend from high power free-electron lasers and recirculated linac light sources, to electron coolers for high energy colliders or actual electron-ion colliding- beam machines based on an energy recovered linac for the electrons.

  8. Recirculated and Energy Recovered Linacs

    CERN Document Server

    Geoffr-Ey-Kraff

    2003-01-01

    Linacs that are recirculated share many characteristics with ordinary linacs, including the ability to accelerate electron beams FR-om an injector to high energy with relatively little (normalized) emittance growth and the ability to deliver ultrashort bunch duration pulses to users. When such linacs are energy recovered, the additional possibility of accelerating very high average beam current arises. Because this combination of beam properties is not possible FR-om either a conventional linac, or FR-om storage rings where emittance and pulse length are set by the equilibrium between radiation damping and quantum excitation of oscillations about the closed orbit, energy recovered linacs are being considered for an increasing variety of applications. These possibilities extend FR-om high power FR-ee-electron lasers and recirculated linac light sources, to electron coolers for high energy colliders or actual electron-ion colliding- beam machines based on an energy recovered linac for the electrons.

  9. Change in Species Diversity during Recovering Process of Evergreen Broad-leaved Forest%常绿阔叶林恢复过程植物物种多样性的变化

    Institute of Scientific and Technical Information of China (English)

    温远光

    2005-01-01

    Evergreen broad-leaved forest is one of the most important vegetation types in China. Because of the human activities, evergreen broad-leaved forest has been destroyed extensively, leading to degraded ecosystem. It is urgent to conserve and restore these natural forests in China.In this paper, the tendency and rate of species diversity restoration of the evergreen broad-leaved forest in Daming Mountain has been studied. The main results are as follows: (a) In subtropical mid-mountain area, species diversity in degraded evergreen broad-leaved forest can be restored. Through analyzing b diversity index of communities in different time and space, it was found that the species composition of communities tend to be the same as that in the zonal evergreen broad-leaved forest. (b) The restoration rate of evergreen broad-leaved forest was very fast. Planting Chinese fir after clear-cutting and controlled burning of the forest, 178 species appeared in a 600m2 sample area after 20years'natural recovering. Among these species, 58 were tree layer and the height of community reached 18m. The survey suggested that it would take only 20 years for the degraded forest to develop into community composed of light demanding broad-leaved pioneer trees and min-tolerance broad-leaved trees, and it need another 40~80 years to reach the stage consisting of min-tolerance evergreen broad-leaved trees. (c) Species number increased quickly at the early stage (2-20 years) during vegetation recovering process toward the climax, and decreased at the min-stage (50-60 years ), then maintained a relatively stable level at the late-stage (over 150 years).

  10. Personality in recovered depressed elderly.

    Science.gov (United States)

    Schneider, L S; Zemansky, M F; Bender, M; Sloane, R B

    1992-01-01

    Personality traits in euthymic elderly subjects with and without past histories of major depressive episodes were assessed using the Structured Clinical Interview for DSM-III-R and the Social Adjustment Scale-SR. Recovered depressed subjects were characterized by significantly more personality traits from DSM-III-R Clusters B and C than controls, and they exhibited differences in social adjustment, as well. Subjects who have recovered from depressive episodes may show significant differences in personality and social adjustment that might represent residua of past depression, a trait characteristic, or a risk factor for recurrence.

  11. Exposure of Lima bean leaves to volatiles from herbivore-induced conspecific plants results in emission of carnivore attractants: active or passive process?

    NARCIS (Netherlands)

    Choh, Y.; Shimoda, T.; Ozawa, R.; Dicke, M.; Takabayashi, J.

    2004-01-01

    There is increasing evidence that volatiles emitted by herbivore-damaged plants can cause responses in downwind undamaged neighboring plants, such as the attraction of carnivorous enemies of herbivores. One of the open questions is whether this involves an active (production of volatiles) or passive

  12. 攀钢含钛高炉渣湿法提钛工艺%Hydrometallurgical process for recovering titanium from titanium-bearing blast furnace slag in Panzhihua Steel Plant

    Institute of Scientific and Technical Information of China (English)

    王浩然; 张延玲; 安卓卿; 赵世强

    2016-01-01

    酸浸法提钛工艺可以获得较高TiO2含量的产物,但是该工艺所产生的酸浸液存在难回收的问题。采用碱浸法可以避免酸浸液回收的问题,但是该工艺流程比较复杂,钠盐的回收成本较高。酸碱法在理论上可以将含钛高炉渣转化为富钛料,然而该工艺流程相对复杂,工业应用还需要不断深入研究与完善。针对采用湿法工艺从攀钢含钛高炉渣中提钛的各项技术,从技术、经济、环保等方面进行对比分析,指出需要将湿法工艺与火法工艺联合,同时将一些外场冶金技术引入到含钛高炉渣的提钛分离过程中,从而有望高效、综合利用攀钢含钛高炉渣。%High purity TiO2-containing product is prepared by acid leaching method. However, the pickle liquor recycling remains a difficult problem, which can be avoided by using the alkaline leaching method, but this process is complex and the recovering cost of sodium salt is a bit high. The acid-alkali method can change the Ti-bearing blast-furnace slag into rich-titanium material theoretically, while this process is complex too, which needs further study and perfection. A variety of pyrometallurgy technologies to recover titanium from ti-tanium bearing blast furnace slag are comprehensively reviewed and a comparative analysis is made from as-pect of technological, economic and environmental protection. It is pointed out that efficient and comprehen-sive utilization of titanium bearing blast furnace slag requires combining pyrometallurgy with hydro metallur-gical process, as well as some external field metallurgy technology.

  13. Ventilation and Heat Recovering System

    Directory of Open Access Journals (Sweden)

    Olga Bancea

    2007-01-01

    Full Text Available Some aspects concerning the heat reducing for ventilation, achieved by using heat recovering components and a combined heating--ventilating system, assuring both comfort and human health are presented. The floor imbedded systems together with air outlets elements could fulfill all the aesthetically desires, as well as comfort and they are ideal for family houses.

  14. Method for sampling and analysis of volatile biomarkers in process gas from aerobic digestion of poultry carcasses using time-weighted average SPME and GC-MS.

    Science.gov (United States)

    Koziel, Jacek A; Nguyen, Lam T; Glanville, Thomas D; Ahn, Heekwon; Frana, Timothy S; Hans van Leeuwen, J

    2017-10-01

    A passive sampling method, using retracted solid-phase microextraction (SPME) - gas chromatography-mass spectrometry and time-weighted averaging, was developed and validated for tracking marker volatile organic compounds (VOCs) emitted during aerobic digestion of biohazardous animal tissue. The retracted SPME configuration protects the fragile fiber from buffeting by the process gas stream, and it requires less equipment and is potentially more biosecure than conventional active sampling methods. VOC concentrations predicted via a model based on Fick's first law of diffusion were within 6.6-12.3% of experimentally controlled values after accounting for VOC adsorption to the SPME fiber housing. Method detection limits for five marker VOCs ranged from 0.70 to 8.44ppbv and were statistically equivalent (p>0.05) to those for active sorbent-tube-based sampling. The sampling time of 30min and fiber retraction of 5mm were found to be optimal for the tissue digestion process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. An ultra-low-power area-efficient non-volatile memory in a 0.18 μ m single-poly CMOS process for passive RFID tags

    Institute of Scientific and Technical Information of China (English)

    Jia Xiaoyun; Feng Peng; Zhang Shengguang; Wu Nanjian; Zhao Baiqin; Liu Su

    2013-01-01

    This paper presents an ultra-low-power area-efficient non-volatile memory (NVM) in a 0.18μm singlepoly standard CMOS process for passive radio frequency identification (RFID) tags.In the memory cell,a novel low-power operation method is proposed to realize bi-directional Fowler-Nordheim tunneling during write operation.Furthermore,the cell is designed with PMOS transistors and coupling capacitors to minimize its area.In order to improve its reliability,the cell consists of double floating gates to store the data,and the 1 kbit NVM was implemented in a 0.18μm single-poly standard CMOS process.The area of the memory cell and 1 kbit memory array is 96μm2 and 0.12 mm2,respectively.The measured results indicate that the program/erase voltage ranges from 5 to 6 V.The power consumption of the read/write operation is 0.19μW/0.69 μW at a read/write rate of (268 kb/s)/(3.0 kb/s).

  16. CAM Stochastic Volatility Model for Option Pricing

    Directory of Open Access Journals (Sweden)

    Wanwan Huang

    2016-01-01

    Full Text Available The coupled additive and multiplicative (CAM noises model is a stochastic volatility model for derivative pricing. Unlike the other stochastic volatility models in the literature, the CAM model uses two Brownian motions, one multiplicative and one additive, to model the volatility process. We provide empirical evidence that suggests a nontrivial relationship between the kurtosis and skewness of asset prices and that the CAM model is able to capture this relationship, whereas the traditional stochastic volatility models cannot. We introduce a control variate method and Monte Carlo estimators for some of the sensitivities (Greeks of the model. We also derive an approximation for the characteristic function of the model.

  17. Spiral mining for lunar volatiles

    Science.gov (United States)

    Schmitt, H. H.; Kulcinski, G. L.; Sviatoslavsky, I. N.; Carrier, W. D., III

    Lunar spiral mining, extending outward from a periodically mobile central power and processing station represents an alternative for comparison with more traditional mining schemes. In this concept, a mining machine would separate regolith fines and extract the contained volatiles. Volatiles then would be pumped along the miner's support arm to the central station for refining and for export or storage. The basic architecture of the central processing station would be cylindrical. A central core area could house the power subsystem of hydrogen-oxygen engines or fuel cells. Habitat sections and other crew occupied areas could be arranged around the power generation core. The outer cylinder could include all volatile refining subsystems. Solar thermal power collectors and reflectors would be positioned on top of the central station. Long term exploitation of a volatile resource region would begin with establishment of a support base at the center of a long boundary of the region. The mining tract for each spiral mining system would extend orthogonal to this boundary. New spiral mining systems would be activated along parallel tracts as demand for lunar He-3 and other solar wind volatiles increased.

  18. Chemical diversity of organic volatiles among comets: An emerging taxonomy and implications for processes in the proto-planetary disk

    Science.gov (United States)

    Mumma, Michael J.

    2008-10-01

    As messengers from the early Solar System, comets contain key information from the time of planet formation and even earlier some may contain material formed in our natal interstellar cloud. Along with water, the cometary nucleus contains ices of natural gases (CH4, C2H6), alcohols (CH3OH), acids (HCOOH), embalming fluid (H2CO), and even anti-freeze (ethylene glycol). Comets today contain some ices that vaporize at temperatures near absolute zero (CO, CH4), demonstrating that their compositions remain largely unchanged after 4.5 billion years. By comparing their chemical diversity, several distinct cometary classes have been identified but their specific relation to chemical gradients in the proto-planetary disk remains murky. How does the compositional diversity of comets relate to nebular processes such as chemical processing, radial migration, and dynamical scattering? No current reservoir holds a unique class, but their fractional abundance can test emerging dynamical models for origins of the scattered Kuiper disk, the Oort cloud, and the (proposed) main-belt comets. I will provide a simplified overview emphasizing what we are learning, current issues, and their relevance to the subject of this Symposium.

  19. Effects of processing methods on composition and functionality of volatile components isolated from immature fruits of atemoya.

    Science.gov (United States)

    Liu, Tai-Ti; Chao, Louis Kuo-Ping; Peng, Chi-Wei; Yang, Tsung-Shi

    2016-07-01

    Atemoya is one of the most important commercial fruits of the family Annonaceae. The immature fruits of atemoya amply produced from a fruit-thinning process is normally regarded as waste and discarded. This research aimed at studying antimicrobial, antioxidant, and anti-inflammatory activities of the essential oil (EO) isolated from the immature fruits to explore its potential application. The fruits were subjected to different drying methods: solar drying (SD), oven drying at 30°C (OD-30), and at 50°C (OD-50). The oven drying method gave a higher EO yield than the solar drying method. Spathulenol was the largest compound in the EO after the drying process. Antimicrobial effect was not affected by the different drying methods. Antioxidant activity of the EO was measured by DPPH, nitric oxide, and reducing power methods. The EOOD-50 exhibited a stronger antioxidant activity than EOSD and EOOD-30. The EO also showed an anti-inflammatory activity in a cell model.

  20. Volatile Organic Compounds (VOCs)

    Science.gov (United States)

    ... Contact Us Share Volatile Organic Compounds' Impact on Indoor Air Quality On this page: Introduction Sources Health Effects Levels in Homes Steps to Reduce Exposure Standards or Guidelines Additional Resources Introduction Volatile organic compounds ( ...

  1. 板栗加工工艺对挥发性香气成分的影响%Effect of Processing Technology on Volatile Components of Chinese Chestnut

    Institute of Scientific and Technical Information of China (English)

    崔亚辉; 徐芳; 王丰俊; 王建中; 欧阳杰

    2012-01-01

    Chinese chestnut forms different flavors by different processing technology. An automatic thermal de-sorption-gas chromatography-mass spectrometric (ATD-GC-MS) system was applied to analyze the volatile composition of raw chestnut, boiled chestnut, fried chestnut and roasted chestnut. Herbaceous aroma such as ethyl acetate, hex-anal, butyl acetate, 1-butanol-3-methyl-acetate, alpha-pinene and benzaldehyde were found in raw chestnut; fried chestnut and roasted chestnut were found to have characteristic volatiles such as 2-pentyl-furan, 3-carene, 4-hydroxy-2-butanone and 2-methyl-tetrahydrofuran-3-ketone; and in boiled chestnut, spiro [2,4] hepta-4,6-diene was found first time. The results will provide a reference for the further research and development of Chinese chestnut products.%板栗经过不同的加工工艺熟化后会产生不同的风味.文中分别对生板栗,以及煮制、炒制和烤制加工后的板栗进行ATD热脱附以及GC-MS分析,得出不同加工工艺条件下的板栗挥发性香气成分.其中生板栗主要有板栗本身的草本清香香气成分,如乙酸乙酯、己醛、乙酸丁酯、3-甲基-1-丁醇乙酸酯、α-蒎烯和苯甲醛等;炒板栗和烤板栗的特征性挥发物有2-戊基呋喃、3-蒈烯、4-羟基-2-丁酮和2-甲基-四氢呋喃-3-酮;煮板栗中发现了之前未在板栗香气研究中报道过的香气成分螺[2,4]庚-4.6-二烯.

  2. Determination of volatiles produced during radiation processing in food and medicinal herbs; Determinacao de volateis produzidos durante o processamento por radiacao em ervas alimenticias e medicinais

    Energy Technology Data Exchange (ETDEWEB)

    Salum, Debora Christina

    2008-07-01

    In order to protect food from pathogenic microorganisms as well as to increase its shelf life while keeping sensorial properties (e.g. odor and taste), once the latter are one of the main properties required by spice buyers, it is necessary to analyze volatile formation from irradiation of medicinal and food herbs. The aim of the present study was to analyze volatile formation from Co irradiation of Laurus Cinnamomum, Piper Nigrum, Origanum Vulgare and Myristica Fragans. Possible changes on the odor of these herbs are evaluated by characterizing different radiation doses and effects on sensorial properties in order to allow better application of irradiation technology. l he samples have been irradiated in plastic packages by making use of a {sup 60}Co Gamma irradiator. Irradiation doses of 0, 5, 10, 15, 20 and 25kGy have been tested. For the analysis of the samples, SPME has been applied, while for the analysis of volatile compounds, CG/MS. Spice irradiation has promoted mostly decrease in volatile compounds when doses of 5, 10, 15, 20 and 25kGy were used. For Laurus cinnamomum, the irradiation decreased volatile by nearly 56% and 89.5% respectively, comparing to volatile from a sample which has not been previously irradiated. Differently from other spices analyzed, irradiation on Myristica Fragans has increased volatile compounds except for 4-terpineol. The miristicine (toxic substance when in large quantities, commonly mentioned as narcotic) has increased by nearly 80%. For Origanum Vulgare and Piper Nigrum, significant decrease in volatile compounds have been found, mainly when it comes to 25 kGy irradiation. In general, results indicate loss of sensorial quality of spices. (author)

  3. Production of poly(hydroxybutyrate-hydroxyvalerate) from waste organics by the two-stage process: focus on the intermediate volatile fatty acids.

    Science.gov (United States)

    Shen, Liang; Hu, Hongyou; Ji, Hongfang; Cai, Jiyuan; He, Ning; Li, Qingbiao; Wang, Yuanpeng

    2014-08-01

    The two-stage process, coupling volatile fatty acids (VFAs) fermentation and poly(hydroxybutyrate-hydroxyvalerate) (P(HB/HV)) biosynthesis, was investigated for five waste organic materials. The overall conversion efficiencies were glycerol>starch>molasses>waste sludge>protein, meanwhile the maximum P(HB/HV) (1.674 g/L) was obtained from waste starch. Altering the waste type brought more effects on VFAs composition other than the yield in the first stage, which in turn greatly changed the yield in the second stage. Further study showed that even-number carbon VFAs (or odd-number ones) had a good positive linear relationship with P(HB/HV) content of HB (or HV). Additionally, VFA producing microbiota was analyzed by pyrosequencing methods for five wastes, which indicated that specific species (e.g., Lactobacillus for protein; Ethanoligenens for starch; Ruminococcus and Limnobacter for glycerol) were dominant in the community for VFAs production. Potential competition among acidogenic bacteria specially involved to produce some VFA was proposed as well.

  4. Effect of mixed liquor volatile suspended solids (MLVSS and hydraulic retention time (HRT on the performance of activated sludge process during the biotreatment of real textile wastewater

    Directory of Open Access Journals (Sweden)

    Kapil Kumar

    2014-03-01

    Full Text Available Adequate information is available on colour and organics removal in batch mode using pure microbial cultures from dye contaminated wastewater. There was a need to develop environment friendly and cost effective treatment technique for actual field conditions. Therefore, the present study was undertaken with an aim to evaluate the potential of acclimatized mixed microbial consortia for the removal of colour and organics from real textile wastewater. Experiments were performed in laboratory scale activated sludge process (ASP unit under steady state condition, varying mixed liquor volatile suspended solids (MLVSS (2500, 3500 and 5000 mg/l and hydraulic retention time (HRT (18, 24 and 36 h. The results showed that decolourization and chemical oxygen demand (COD removal increased with increase in MLVSS and HRT. At 18 h HRT, decolourization was found to be 46, 54 and 67%, which increased to 67, 75 and 90% (36 h HRT at 2500, 3500 and 5000 mg/l MLVSS, respectively. COD removal was found to be 62, 73 and 77% (at 18 h HRT which increased to 77, 85 and 91% (36 h HRT at 2000, 3500 and 5000 mg/l MLVSS, respectively. On the basis of the results obtained in this study suitable treatment techniques can be developed for the treatment of wastewater contaminated with variety of dyes in continuous mode of operation. This shall have the advantage of treatment of larger quantity of wastewater in shorter duration.

  5. Method for recovering materials from waste

    Science.gov (United States)

    Wicks, G.G.; Clark, D.E.; Schulz, R.L.

    1994-01-01

    A method for recovering metals from metals-containing wastes, a vitrifying the remainder of the wastes for disposal. Metals-containing wastes such as circuit boards, cathode ray tubes, vacuum tubes, transistors and so forth, are broken up and placed in a suitable container. The container is heated by microwaves to a first temperature in the range of approximately 300--800{degrees}C to combust organic materials in the waste, then heated further to a second temperature in the range of approximately 1000--1550{degrees}C at which temperature glass formers present in the waste will cause it to melt and vitrify. Low-melting-point metals such as tin and aluminum can be recovered after organics combustion is substantially complete. Metals with higher melting points, such as gold, silver and copper, can be recovered from the solidified product or separated from the waste at their respective melting points. Network former-containing materials can be added at the start of the process to assist vitrification.

  6. Energy recycling by co-combustion of coal and recovered paint solids from automobile paint operations.

    Science.gov (United States)

    Suriyawong, Achariya; Magee, Rogan; Peebles, Ken; Biswas, Pratim

    2009-05-01

    During the past decade, there has been substantial interest in recovering energy from many unwanted byproducts from industries and municipalities. Co-combustion of these products with coal seems to be the most cost-effective approach. The combustion process typically results in emissions of pollutants, especially fine particles and trace elements. This paper presents the results of an experimental study of particulate emission and the fate of 13 trace elements (arsenic [As], barium [Ba], cadmium [Cd], chromium [Cr], copper [Cu], cobalt [Co], manganese [Mn], molybdenum [Mo], nickel [Ni], lead [Pb], mercury [Hg], vanadium [V], and zinc [Zn]) during combustion tests of recovered paint solids (RPS) and coal. The emissions from combustions of coal or RPS alone were compared with those of co-combustion of RPS with subbituminous coal. The distribution/partitioning of these toxic elements between a coarse-mode ash (particle diameter [dp] > 0.5 microm), a submicrometer-mode ash (dp burning particles and the higher volatile chlorine species. Hg was completely volatilized in all cases; however, the fraction in the oxidized state increased with co-combustion. Most trace elements, except Zn, were retained in ash during combustion of RPS alone. Mo was mostly retained in all samples. The behavior of elements, except Mn and Mo, varied depending on the fuel samples. As, Ba, Cr, Co, Cu, and Pb were vaporized to a greater extent from cocombustion of RPS and coal than from combustion of either fuel. Evidence of the enrichment of certain toxic elements in submicrometer particles has also been observed for As, Cd, Cr, Cu, and Ni during co-combustion.

  7. A Retrospective: Active Volatile-Driven Geologic Processes Across the Solar System—Lessons for Planetary Explorers

    Science.gov (United States)

    Soderblom, L. A.

    2014-12-01

    When Voyagers 1 and 2 left Earth in 1977, we had little clue as to the rich variety of activity we'd find on the outer Solar System moons. The moons of Jupiter, Saturn, Uranus, and Neptune would likely exhibit little geologic evolution¾much less even than our Moon. We expected battered, cratered, dead worlds. Like the Moon, Mars had showed volcanic activity in the geologic past, but ancient, heavily crater highlands dominated both surfaces. It seemed unlikely that we'd find even extinct volcanism in the cold, dead reaches of the outer Solar System. Voyager 1 shocked us by revealing Io's prolific ongoing volcanism. (Not all were surprised: just days earlier, Peale, Cassen, and Reynolds published a prediction that Io could be volcanically active). Europa, too, was a Voyager surprise; only a small handful of impact craters pocked its surface. It too had to be a geologically young body—likely still actively evolving. We have even found very recent geological activity on tiny cometary nuclei, where young flows have oozed forth across their surfaces. At Neptune, incredibly, Voyager 2 found eruptions on Triton's 37K polar cap—plumes driven by solar-heated nitrogen gas blasting dark dust and bright ice in 8-km-high columns. On Mars, "dark spiders" near the pole signaled similar active eruptions, in this case driven by pressurized carbon dioxide. Cassini witnessed a myriad of jets near tiny Enceladus' south pole, arising from an internal ocean evidently driven by active chemical processes and modulated by Saturn's proximity. Cassini revealed Titan to be Earth's alien twin, with a host of processes borrowed from textbooks on terrestrial geomorphology and meteorology. Akin to Earth's global hydrological cycle, Titan's runs on methane—methane rivers, seas, and rain abound. What lessons can we take from these active places into the next phase of exploration? When the Voyagers were launched, our naiveté allowed that only planet Earth was dynamically active. But exploring

  8. Determination of refractive and volatile elements in sediment using laser ablation inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Duodu, Godfred Odame; Goonetilleke, Ashantha; Allen, Charlotte; Ayoko, Godwin A

    2015-10-22

    Wet-milling protocol was employed to produce pressed powder tablets with excellent cohesion and homogeneity suitable for laser ablation (LA) analysis of volatile and refractive elements in sediment. The influence of sample preparation on analytical performance was also investigated, including sample homogeneity, accuracy and limit of detection. Milling in volatile solvent for 40 min ensured sample is well mixed and could reasonably recover both volatile (Hg) and refractive (Zr) elements. With the exception of Cr (-52%) and Nb (+26%) major, minor and trace elements in STSD-1 and MESS-3 could be analysed within ±20% of the certified values. Comparison of the method with total digestion method using HF was tested by analysing 10 different sediment samples. The laser method recovers significantly higher amounts of analytes such as Ag, Cd, Sn and Sn than the total digestion method making it a more robust method for elements across the periodic table. LA-ICP-MS also eliminates the interferences from chemical reagents as well as the health and safety risks associated with digestion processes. Therefore, it can be considered as an enhanced method for the analysis of heterogeneous matrices such as river sediments.

  9. Stochastic Volatility and DSGE Models

    DEFF Research Database (Denmark)

    Andreasen, Martin Møller

    This paper argues that a specification of stochastic volatility commonly used to analyze the Great Moderation in DSGE models may not be appropriate, because the level of a process with this specification does not have conditional or unconditional moments. This is unfortunate because agents may...

  10. Thermoset composite recycling: Properties of recovered glass fiber

    DEFF Research Database (Denmark)

    Beauson, Justine; Fraisse, Anthony; Toncelli, C.

    2015-01-01

    Recycling of glass fiber thermoset polymer composite is a challenging topic and a process able to recover the glass fibers original properties in a limited cost is still under investigation. This paper focuses on the recycling technique separating the glass fiber from the matrix material. Four...... different recycling processes, mechanical, burn off, pyrolysis and glycolysis are selected are compared based on the properties of the glass fiber recovered. The intention is to use the same characterization methodology....

  11. Securing non-volatile memory regions

    Science.gov (United States)

    Faraboschi, Paolo; Ranganathan, Parthasarathy; Muralimanohar, Naveen

    2013-08-20

    Methods, apparatus and articles of manufacture to secure non-volatile memory regions are disclosed. An example method disclosed herein comprises associating a first key pair and a second key pair different than the first key pair with a process, using the first key pair to secure a first region of a non-volatile memory for the process, and using the second key pair to secure a second region of the non-volatile memory for the same process, the second region being different than the first region.

  12. Implementation of online volatile fatty acids sensor for control and optimization of anaerobic process for low cost biogas production from manure. Project report

    Energy Technology Data Exchange (ETDEWEB)

    Boe, K.; Angelidaki, I.

    2010-10-15

    Proper monitoring and control can improve process stability and enhance process performance for better economy of the biogas plants. Volatile fatty acid (VFA) is the most widely recognized as a direct, relevant measure of stability. Classic on-line measurement of individual VFA is based on filtration, which suffers from fouling when applied with manure slurries. A VFA sensor developed at DTU Environment, based on headspace chromatography technique could avoid the problems from particulate matters. In this work, the sensor had been implemented for online monitoring of the lab-scale and the pilot-scale manure digester. The industrial prototype of the VFA sensor and sample acquisition system has been constructed and implemented at a pilot scale biogas plant, located at Lundtofte, DTU. The VFA sensor has shown very satisfying results in terms of sensitivity and reliability for monitoring the biogas process. Moreover, the online VFA and biogas registration data were used as process indicators for automatic control of the biogas reactor. The results from control experiments confirmed that the combination of biogas production, total VFA concentration and propionate concentration could effectively reflect the dynamic state of the process which was very crucial for automatic control. Due to the standardized analyzing condition (pH<2, temperature>70 deg. C), the sensor responses were not affected by the manure composition (TS, VS or the addition of extra organics), which made these results representative for implementing in the full-scale biogas plant where some industrial organic wastes were added to increase the biogas production. During the project period, the sensor design and construction had been modified and tested several times to improve the robustness. However, the implementation of the sensor in full-scale biogas plant would need some further development such as improvement of mechanical design and further up-scaling depending on the dry solid content in the

  13. Recovering valuable elements from flue slime of blast furnace by combining process of mineral and metallurgy%选冶联合技术提取高炉瓦斯泥中有价元素研究

    Institute of Scientific and Technical Information of China (English)

    张晋霞; 邹玄; 张晓亮; 牛福生

    2015-01-01

    After analyzing the properties ,chemical composition of the flue slime from the blast furnace in Tangshan Iron & Steel Company ,the paper proposed the suggestion of recovering valuable elements from flue slime by combining process of mineral and metallurgy .The laboratory test results showed that the iron concentrate with the iron grade 53 .25% and recovery of 51 .05% by tabling gravity separation as well as the carbon concentrate with fixed carbon content of 74 .21% and recovery of 66 .39% by once rough separation and two times cleaning separation were obtained .The addition of sulfuric acid to the final flotation tailings , the leaching rate of zinc is 97 .85% .When the dosage of sodium sulfide is 200kg/t ,the recovery of zinc concentrate can reach to 86 .36% .%在对高炉瓦斯泥性质、矿物成分分析的基础上,采用选冶联合技术对其有价元素进行了提取研究。试验研究表明,瓦斯泥原料经摇床分选后,获得了铁品位为53.25%,回收率为51.05%的铁精矿;摇床尾矿经浮选柱一次粗选两次精选工艺流程,得到碳品位为74.21%、作业回收率为66.39%的碳精矿;最终尾矿采用硫酸进行浸锌试验,锌的浸出率可达97.85%,向浸出液中加入硫化钠用量为200kg/t时,Zn回收率达到86.36%。

  14. Recovering valuable metals from recycled photovoltaic modules.

    Science.gov (United States)

    Yi, Youn Kyu; Kim, Hyun Soo; Tran, Tam; Hong, Sung Kil; Kim, Myong Jun

    2014-07-01

    Recovering valuable metals such as Si, Ag, Cu, and Al has become a pressing issue as end-of-life photovoltaic modules need to be recycled in the near future to meet legislative requirements in most countries. Of major interest is the recovery and recycling of high-purity silicon (> 99.9%) for the production of wafers and semiconductors. The value of Si in crystalline-type photovoltaic modules is estimated to be -$95/kW at the 2012 metal price. At the current installed capacity of 30 GW/yr, the metal value in the PV modules represents valuable resources that should be recovered in the future. The recycling of end-of-life photovoltaic modules would supply > 88,000 and 207,000 tpa Si by 2040 and 2050, respectively. This represents more than 50% of the required Si for module fabrication. Experimental testwork on crystalline Si modules could recover a > 99.98%-grade Si product by HNO3/NaOH leaching to remove Al, Ag, and Ti and other metal ions from the doped Si. A further pyrometallurgical smelting at 1520 degrees C using CaO-CaF2-SiO2 slag mixture to scavenge the residual metals after acid leaching could finally produce > 99.998%-grade Si. A process based on HNO3/NaOH leaching and subsequent smelting is proposed for recycling Si from rejected or recycled photovoltaic modules. Implications: The photovoltaic industry is considering options of recycling PV modules to recover metals such as Si, Ag, Cu, Al, and others used in the manufacturing of the PV cells. This is to retain its "green" image and to comply with current legislations in several countries. An evaluation of potential resources made available from PV wastes and the technologies used for processing these materials is therefore of significant importance to the industry. Of interest are the costs of processing and the potential revenues gained from recycling, which should determine the viability of economic recycling of PV modules in the future.

  15. Technical Research of Recovering Protein from Process Water in Starch Wet Milling System%淀粉工艺水中蛋白回收工艺的研究

    Institute of Scientific and Technical Information of China (English)

    刘泽龙; 潘君慧; 张连慧; 强婉丽

    2015-01-01

    A study was conducted to develop a technique that can recover protein from the process water in starch wet milling system, which mainly include recollecting corn gluten and obtaining two kinds of novel protein from process water produced during the step of major starch/protein separation by membrane filtration incroporating heat treatment. It was found that ultrafiltration membranes with molecular weight cut-off at 50 ku and 100 ku have better effect on the rejection of 30 ku protein fraction , which is in the enrichment of branched chain amino acids such as Leu and Val. In addition , the obtained protein fractions at molecular weight range of 3 ku to 14 ku were found to resist to heat treatment. The novel protein products can be used as food protein ingredient or protein feed with potential application in muscle building and the acid food or beverage , repectively.%为了探索玉米淀粉生产中的工艺水中的蛋白组分的开发利用,研究一种玉米淀粉工艺水蛋白回收工艺,主要包括处理在湿磨法生产玉米淀粉工艺中的麸质浓缩步骤产生的工艺水,并使用膜技术和热处理技术在回收玉米黄粉的同时获得两种新蛋白产品。研究发现,50 ku和100 ku对丰度较高的30 ku蛋白组分的截留浓缩效果较好,其中,该蛋白富含亮氨酸和缬氨酸等支链氨基酸。分离出的耐热耐酸蛋白组分主要为3 ku~14 ku的部分。所得新蛋白产品可作为食用或饲用蛋白原料使用,并且分别具有增肌和用于酸性食品的潜力。

  16. SPME-GC-MS versus Selected Ion Flow Tube Mass Spectrometry (SIFT-MS) analyses for the study of volatile compound generation and oxidation status during dry fermented sausage processing.

    Science.gov (United States)

    Olivares, Alicia; Dryahina, Kseniya; Navarro, José Luis; Smith, David; Spanĕl, Patrik; Flores, Mónica

    2011-03-09

    The use of selected ion flow tube mass spectrometry (SIFT-MS) and gas chromatography-mass spectrometry together with solid phase microextraction (GC-MS-SPME) has been compared in the analysis of volatile compounds during dry fermented sausage processing. Thus, the headspace (HS) of samples of dry fermented sausages with different fat contents was analyzed during their manufacture using both techniques, and significant and positive correlations were found between SIFT-MS and SPME-GC-MS measurements for the compounds pentanal, hexanal, 2-heptenal, octanal, 2-nonenal, 2-butanone, 2-pentanone, ethanol, acetic acid, and hexanoic acid. The oxidative status of fermented sausages during processing was also evaluated, and a significant correlation was obtained between the HS concentration of lipid autoxidation volatile compounds measured by SIFT-MS and SPME-GC-MS and the level of thiobarbituric acid reactive substances (TBARS) in the sausage. The hexanal measured by SIFT-MS resulted in a higher correlation coefficient (r = 0.936) than that obtained using SPME-GC-MS (r = 0.927). SIFT-MS is shown to be a fast, real time analytical technique for monitoring changes in the profile of volatile compounds in dry fermented sausages during processing and a useful tool to evaluate the oxidative status of meat products.

  17. Current status of fluoride volatility method development

    Energy Technology Data Exchange (ETDEWEB)

    Uhlir, J.; Marecek, M.; Skarohlid, J. [UJV - Nuclear Research Institute, Research Centre Rez, CZ-250 68 Husinec - Rez 130 (Czech Republic)

    2013-07-01

    The Fluoride Volatility Method is based on a separation process, which comes out from the specific property of uranium, neptunium and plutonium to form volatile hexafluorides whereas most of fission products (mainly lanthanides) and higher transplutonium elements (americium, curium) present in irradiated fuel form nonvolatile tri-fluorides. Fluoride Volatility Method itself is based on direct fluorination of the spent fuel, but before the fluorination step, the removal of cladding material and subsequent transformation of the fuel into a powdered form with a suitable grain size have to be done. The fluorination is made with fluorine gas in a flame fluorination reactor, where the volatile fluorides (mostly UF{sub 6}) are separated from the non-volatile ones (trivalent minor actinides and majority of fission products). The subsequent operations necessary for partitioning of volatile fluorides are the condensation and evaporation of volatile fluorides, the thermal decomposition of PuF{sub 6} and the finally distillation and sorption used for the purification of uranium product. The Fluoride Volatility Method is considered to be a promising advanced pyrochemical reprocessing technology, which can mainly be used for the reprocessing of oxide spent fuels coming from future GEN IV fast reactors.

  18. Pyrochemical investigations into recovering plutonium from americium extraction salt residues

    Energy Technology Data Exchange (ETDEWEB)

    Fife, K.W.; West, M.H.

    1987-05-01

    Progress into developing a pyrochemical technique for separating and recovering plutonium from spent americium extraction waste salts has concentrated on selective chemical reduction with lanthanum metal and calcium metal and on the solvent extraction of americium with calcium metal. Both techniques are effective for recovering plutonium from the waste salt, although neither appears suitable as a separation technique for recycling a plutonium stream back to mainline purification processes. 17 refs., 13 figs., 2 tabs.

  19. Modelling the Volatility-Return Trade-off when Volatility may be Nonstationary

    DEFF Research Database (Denmark)

    Dahl, Christian Møller; Iglesias, Emma M.

    In this paper a new GARCH-M type model, denoted the GARCH-AR, is proposed. In particular, it is shown that it is possible to generate a volatility-return trade-off in a regression model simply by introducing dynamics in the standardized disturbance process. Importantly, the volatility in the GARCH...

  20. Volatility in Equilibrium

    DEFF Research Database (Denmark)

    Bollerslev, Tim; Sizova, Natalia; Tauchen, George

    Stock market volatility clusters in time, carries a risk premium, is fractionally inte- grated, and exhibits asymmetric leverage effects relative to returns. This paper develops a first internally consistent equilibrium based explanation for these longstanding empirical facts. The model is cast......, and the dynamic cross-correlations of the volatility measures with the returns calculated from actual high-frequency intra-day data on the S&P 500 aggregate market and VIX volatility indexes....

  1. Protein recovered from channel catfish processing by-products via isoelectric solubilization/precipitation and its gelation properties%鮰鱼下脚料蛋白质的回收及其凝胶特性研究

    Institute of Scientific and Technical Information of China (English)

    贡汉坤; 焦云鹏

    2012-01-01

    通过回收并制备鮰鱼下脚料的蛋白质凝胶,考察溶解pH、离心力、离子强度对鱼下脚料中蛋白质的溶解性及凝胶理化性质的影响.结果表明,溶解pH、离心力、离子强度对鱼下脚料中的蛋白质的溶解性能均有显著影响(P<0.05).pH=2.5或pH=11.5,离心力为5 500 r/min,离子强度为0.6M时,蛋白质溶解性能较好,pH=5.5时蛋白质溶解性最差.溶解pH=11.5时,制备的鱼肉凝胶蛋白质、灰分含量较高,脂类含量较低,并且凝胶的破断强度值、凹陷度以及凝胶强度值较高,但凝胶色泽较差.%In the present study, muscle proteins were recovered from channel catfish processing by-products (fish meat leftover on bones, head, skin, and etc. ) by isoelectric solubilization/preciphation. And the effects of solubilization pH, centrifugal force and ionic strengths on protein solubility were investigated by using single-factor experiments. We found that solubilization pH, centrifugal force and ionic strengths had significant effects on protein solubility (P<0. 05). Protein had high solubility when solubilization pH was 2. 5 or 11. 5, and low solubility when solubilization pH was 5. 5. centrifugal force was 5 500 r/min, and ionic strengths were 0. 6 M. And Gels made from protein solubilized at alkali pH (11. 5) had lower content of lip-ids, relative higher contents of protein and ash, higher Breaking force, breaking strain and gel strength, but lower quality than gels from other pH treatments.

  2. The reduction of iron oxides by volatiles in a rotary hearth furnace process: Part II. The reduction of iron oxide/carbon composites

    Science.gov (United States)

    Sohn, I.; Fruehan, R. J.

    2006-04-01

    The reduction of iron oxide/carbon composite pellets with hydrogen at 900 °C to 1000 °C was studied. Compared to hydrogen, the reduction by carbon was negligible at 900 °C and below. However, significant carbon oxidation of the iron oxide/graphite pellets by H2O generated from the reduction of Fe2O3 by H2 was observed. At higher temperatures, reduction by carbon complicates the overall reduction mechanism, with the iron oxide/graphite composite pellet found to be more reactive than the iron oxide/char composite pellet. From the scanning electron micrographs, partially reduced composite pellets showed a typical topochemical interface with an intermediate region between an oxygen-rich unreacted core and an iron-rich outer shell. To determine the possibility of reduction by volatiles, a layer of iron oxide powders was spread on top of a high volatile containing bituminous coal and heated inside a reactor using infra-red radiation. By separating the individual reactions involved for an iron oxide/coal mixture where a complex set of reactions occur simultaneously, it was possible to determine the sole effect of volatile reduction. It was found that the light reducing gases evolve initially and react with the iron oxide, with complex hydrocarbons evolving at the later stages. The volatiles caused about 20 to 50 pct reduction of the iron oxide.

  3. Assessing relative volatility/intermittency/energy dissipation

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole E.; Pakkanen, Mikko S.; Schmiegel, Jürgen

    2014-01-01

    We introduce the notion of relative volatility/intermittency and demonstrate how relative volatility statistics can be used to estimate consistently the temporal variation of volatility/intermittency when the data of interest are generated by a non-semimartingale, or a Brownian semistationary...... process in particular. This estimation method is motivated by the assessment of relative energy dissipation in empirical data of turbulence, but it is also applicable in other areas. We develop a probabilistic asymptotic theory for realised relative power variations of Brownian semistationary processes......, and introduce inference methods based on the theory. We also discuss how to extend the asymptotic theory to other classes of processes exhibiting stochastic volatility/intermittency. As an empirical application, we study relative energy dissipation in data of atmospheric turbulence....

  4. Estimation of Stochastic Volatility Models by Nonparametric Filtering

    DEFF Research Database (Denmark)

    Kanaya, Shin; Kristensen, Dennis

    2016-01-01

    /estimated volatility process replacing the latent process. Our estimation strategy is applicable to both parametric and nonparametric stochastic volatility models, and can handle both jumps and market microstructure noise. The resulting estimators of the stochastic volatility model will carry additional biases......A two-step estimation method of stochastic volatility models is proposed: In the first step, we nonparametrically estimate the (unobserved) instantaneous volatility process. In the second step, standard estimation methods for fully observed diffusion processes are employed, but with the filtered...... and variances due to the first-step estimation, but under regularity conditions we show that these vanish asymptotically and our estimators inherit the asymptotic properties of the infeasible estimators based on observations of the volatility process. A simulation study examines the finite-sample properties...

  5. The Age of Lunar South Circumpolar Craters Haworth, Shoemaker, Faustini, and Shackleton: Implications for Regional Geology, Surface Processes, and Volatile Sequestration

    Science.gov (United States)

    Tye, A. R.; Fassett, C. I.; Head, J. W.; Mazarico, E.; Basilevsky, A. T.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

    2015-01-01

    The interiors of the lunar south circumpolar craters Haworth, Shoemaker, Faustini, and Shackleton contain permanently shadowed regions (PSRs) and have been interpreted to contain sequestered volatiles including water ice. Altimetry data from the Lunar Orbiter Laser Altimeter (LOLA) onboard the Lunar Reconnaissance Orbiter provide a new means of examining the permanently shadowed interiors of these craters in unprecedented detail. In this study, we used extremely high-resolution gridded LOLA data of Haworth, Shoemaker, Faustini, and Shackleton to determine the size-frequency distributions and the spatial density of craters superposing their rims, inner slopes, and floors. Based on their population of superposed D greater than or equal to 2 km craters, Haworth, Shoemaker, and Faustini have pre-Nectarian formation ages. Shackleton is interpreted as having a Late Imbrian age on the basis of craters with diameter D greater than or equal to 0.5 km superposed on its rim. The local density of craters with sub-km diameters across our study area is strongly dependent on slope; because of its steep interior slopes, the lifetime of craters on the interior of Shackleton is limited. The slope-dependence of the small crater population implies that the population in this size range is controlled primarily by the rate at which craters are destroyed. This is consistent with the hypothesis that crater removal and resurfacing is a result of slopedependent processes such as diffusive mass wasting and seismic shaking, linked to micrometeorite and meteorite bombardment. Epithermal neutron flux data and UV albedo data show that these circumpolar PSRs, particularly Shoemaker, may have approximately 1-2% water ice by mass in their highly porous surface regolith, and that Shoemaker may have approximately 5% or more water ice by mass in the near subsurface. The ancient formation ages of Shoemaker, Faustini and Haworth, and the Late Imbrian (approximately 3.5 Ga) crater retention ages of their

  6. Understanding Financial Market Volatility

    NARCIS (Netherlands)

    A. Opschoor (Anne)

    2014-01-01

    markdownabstract__Abstract__ Volatility has been one of the most active and successful areas of research in time series econometrics and economic forecasting in recent decades. Loosely speaking, volatility is defined as the average magnitude of fluctuations observed in some phenomenon over time. Wi

  7. Improving Garch Volatility Forecasts

    NARCIS (Netherlands)

    Klaassen, F.J.G.M.

    1998-01-01

    Many researchers use GARCH models to generate volatility forecasts. We show, however, that such forecasts are too variable. To correct for this, we extend the GARCH model by distinguishing two regimes with different volatility levels. GARCH effects are allowed within each regime, so that our model

  8. Understanding Financial Market Volatility

    NARCIS (Netherlands)

    A. Opschoor (Anne)

    2014-01-01

    markdownabstract__Abstract__ Volatility has been one of the most active and successful areas of research in time series econometrics and economic forecasting in recent decades. Loosely speaking, volatility is defined as the average magnitude of fluctuations observed in some phenomenon over

  9. Volatile metabolites from actinomycetes

    DEFF Research Database (Denmark)

    Scholler, C.E.G.; Gurtler, H.; Pedersen, R.

    2002-01-01

    Twenty-six Streptomyces spp. were screened for their volatile production capacity on yeast starch agar. The volatile organic compounds (VOCs) were concentrated on a porous polymer throughout an 8-day growth period. VOCs were analyzed by gas chromatography with flame ionization detection and ident...

  10. Volatile compounds in meat and meat products

    Directory of Open Access Journals (Sweden)

    Monika KOSOWSKA

    Full Text Available Abstract Meaty flavor is composed of a few hundreds of volatile compounds, only minor part of which are responsible for the characteristic odor. It is developed as a result of multi-directional reactions proceeding between non-volatile precursors contained in raw meat under the influence of temperature. The volatile compounds are generated upon: Maillard reactions, lipid oxidation, interactions between Maillard reaction products and lipid oxidation products as well as upon thiamine degradation. The developed flavor is determined by many factors associated with: raw material (breed, sex, diet and age of animal, conditions and process of slaughter, duration and conditions of meat storage, type of muscle, additives applied and the course of the technological process. The objective of this review article is to draw attention to the issue of volatile compounds characteristic for meat products and factors that affect their synthesis.

  11. Chlorine and fluorine partition coefficients and abundances in sub-arc mantle xenoliths (Kamchatka, Russia): Implications for melt generation and volatile recycling processes in subduction zones

    Science.gov (United States)

    Bénard, A.; Koga, K. T.; Shimizu, N.; Kendrick, M. A.; Ionov, D. A.; Nebel, O.; Arculus, R. J.

    2017-02-01

    We report chlorine (Cl) and fluorine (F) abundances in minerals, interstitial glasses, and melt inclusions in 12 andesite-hosted, spinel harzburgite xenoliths and crosscutting pyroxenite veins exhumed from the sub-arc lithospheric mantle beneath Avacha volcano in the Kamchatka Arc (NE Russia). The data are used to calculate equilibrium mineral-melt partition coefficients (D mineral / melt) for Cl and F relevant to subduction-zone processes and unravel the history of volatile depletion and enrichment mechanisms in an arc setting. Chlorine is ∼100 times more incompatible in pyroxenes (DClmineral/melt = 0.005-0.008 [±0.002-0.003]) than F (DFmineral/melt = 0.50-0.57 [±0.21-0.24]), which indicates that partial melting of mantle sources leads to strong depletions in Cl relative to F in the residues. The data set in this study suggests a strong control of melt composition on DCl,Fpyroxene/melt, in particular H2O contents and Al/(Al + Si), which is in line with recent experiments. Fluorine is compatible in Ca-amphibole in the 'wet' sub-arc mantle (DFamphibole/melt = 3.5-3.7 [±1.5]) but not Cl (DClamphibole/melt = 0.03-0.05 [±0.01-0.03]), indicating that amphibole may fractionate F from Cl in the mantle wedge. The inter-mineral partition coefficients for Cl and F in this study are consistent amongst different harzburgite samples, whether they contain glass or not. In particular, disseminated amphibole hosts much of the Cl and F bulk rock budgets of spinel harzburgites (DClamphibole/pyroxene up to 14 and DFamphibole/pyroxene up to 40). Chlorine and fluorine are variably enriched (up to 1500 ppm Cl and 750 ppm F) in the parental arc picrite and boninite melts of primitive pyroxenite veins (and related melt inclusions) crosscutting spinel harzburgites. Based on the data in this study, the main inferences on the behaviour of Cl and F during melting and metasomatic processes in the sub-arc mantle are as follow: (i) Melting models show that most depleted mantle protoliths

  12. Potential of derived lunar volatiles for life support

    Science.gov (United States)

    Bula, R. J.; Wittenberg, L. J.; Tibbitts, T. W.; Kulcinski, G. L.

    1992-01-01

    The lunar regolith contains small quantities of solar wind implanted volatile compounds that have vital, basic uses for maintaining life support systems of lunar or space settlements. Recent proposals to utilize the helium-3 isotope (He-3) derived from the lunar regolith as a fuel for fusion reactors would result in the availability of large quantities of other lunar volatile compounds. The quantities obtained would provide the annual life support replacement requirements of 1150 to 23,000 inhabitants per ton of He-3 recovered, depending on the volatile compound. Utilization of the lunar volatile compounds for life support depends on the costs, in terms of materials and energy, associated with their extraction from the lunar regolith as compared to the delivery costs of these compounds from Earth resources. Considering today's conservative estimated transportation costs ($10,000 dollars per kilogram) and regolith mining costs ($5 dollars per ton), the life support replacement requirements could be more economically supplied by recovering the lunar volatile compounds than transporting these materials from Earth resources, even before He-3 will be utilized as a fusion fuel. In addition, availability of lunar volatile compounds could have a significant cost impact on maintaining the life support systems of the space station and a Mars base.

  13. Mimic-biology research on self-recovering mechanism of cavity-type crack

    Institute of Scientific and Technical Information of China (English)

    YUAN; Chaolong; (袁朝龙); ZHONG; Yuexian; (钟约先); MA; Qingxian; (马庆贤); CAO; Qixiang; (曹起骧)

    2002-01-01

    Modeling method was used to research the recovering law of inner cavity-type cracks during the processes of high-temperature plastic deformation. It was found that the self-recovering of cavity-type fault was similar to the self-healing of wound of skin and fracture. The self-recovering process of cavity-type fault was investigated according to the rule of self-healing of wound in human body. The recrystallization mechanism of self-recovering of cavity-type fault was discovered. A new method is presented to study the self-recovering mechanism of cavity-type cracks.

  14. Idiosyncratic Volatility Puzzle

    DEFF Research Database (Denmark)

    Aslanidis, Nektarios; Christiansen, Charlotte; Lambertides, Neophytos;

    from a large pool of macroeconomic and Önancial variables. Cleaning for macro-Önance e§ects reverses the puzzling negative relation between returns and idiosyncratic volatility documented previously. Portfolio analysis shows that the e§ects from macro-Önance factors are economically strong......In this paper, we scrutinize the cross-sectional relation between idiosyncratic volatility and stock returns. As a novelty, the idiosyncratic volatility is obtained by conditioning upon macro-Önance factors as well as upon traditional asset pricing factors. The macro-Önance factors are constructed...

  15. Recovering Innocence: Growing Up Reading.

    Science.gov (United States)

    Spencer, Patricia Sylvester

    1991-01-01

    Offers a plan for changing the perception among teenagers that reading for pleasure is an activity of their childhood past. Suggests an elective Reading Workshop that allows students to share favorite books and authors, to read aloud and listen to others read aloud, and to discuss their reading processes and decisions. (PRA)

  16. On guidance and volatility

    NARCIS (Netherlands)

    Billings, M.B.; Jennings, R.; Lev, B.

    2013-01-01

    Survey evidence suggests that managers voluntarily disclose information, particularly earnings guidance, with an aim toward dampening share price volatility. Yet, consultants and influential institutions advise against providing guidance — citing fears of litigation and market penalties associated w

  17. Dynamic Volatility Arbitrage

    DEFF Research Database (Denmark)

    Dorn, Jochen

    profit on well-developed markets. Dynamic participation features on cross asset portfolios are at rst sight a remedy to that dilemma. Based on volatility thresholds and portfolio re-balancing, the fund engineers try to create a "volatility guaranteed" investment opportunity by surfing on the unusual high...... concepts, next to nothing is known about position reverting strategies and how, and -even more important- in which context they are applied in practice. In the recent market downturn only one sector generated signicant profits for the leading investment banks: Volatility trading activities, namely on Forex......, interest rates and commodities. If an investor positions himself on the (volatility) market within a long/short trading framework, he typically bets on a traditional mispricing arbitrage. However as this corresponds to a call spread with equal exercise prices, this strategy alone would not generate enough...

  18. It’s all about volatility of volatility

    DEFF Research Database (Denmark)

    Grassi, Stefano; Santucci de Magistris, Paolo

    2015-01-01

    for the realized volatility series. It emerges that during the recent financial crisis the relative weight of the daily component dominates over the monthly term. The estimates of the two factor stochastic volatility model suggest that the change in the dynamic structure of the realized volatility during...... the financial crisis is due to the increase in the volatility of the persistent volatility term. A set of Monte Carlo simulations highlights the robustness of the methodology adopted in tracking the dynamics of the parameters....

  19. Examining Moderate Volatile Loss through Lunar History

    Science.gov (United States)

    Saxena, Prabal; Killen, Rosemary M.; Airapetian, Vladimir; Petro, Noah; Mandell, Avi

    2017-06-01

    While the Moon and bulk silicate earth (BSE) share many compositional similarities, a notable difference is the apparent depletion of moderate volatiles in lunar samples. Depletion of elements such as sodium and potassium relative to BSE composition has been observed in Apollo samples. The source of these depletions is poorly understood but may be a result of preferential accretion of volatile-rich melt in the inner disk to the Earth during Moon formation.However, recent Kepler data has indicated that stellar analogues to our Sun experience enhanced flare activity early in their evolution. This implies that the Sun may have had a higher frequency and energy of flares and associated Coronal Mass Ejections (CME) in its distant past. We examine the potential impacts of this increased activity on lunar exosphere generation and specifically on potential loss of moderate volatiles including sodium and potassium.We use a surface bounded exosphere model that incorporates multiple processes including photon stimulated desorption, kinetic sputtering and impact vaporization in order to study potential moderate volatile loss under a variety of different conditions. This model is informed by appropriate solar wind and CME properties, which includes CMEs of different energies. We also incorporate regolith overturn to determine ranges of potential bulk depletion of moderate volatiles from the lunar regolith.Our work is aimed at determining the potential impact of solar activity on the depletion of moderate volatiles in the lunar regolith. Such a contribution is important to ascertain in order to isolate the depletion of volatiles due to disk processes and may thus help constrain details of the Moon's formation. Finally, we also examine the potential of lunar abundances of moderate volatiles as an observational tracer of past solar activity.

  20. Volatile halogenated hydrocarbons in foods

    Energy Technology Data Exchange (ETDEWEB)

    Miyahara, Makoto; Toyoda, Masatake; Saito, Yukio [National Institute of Health Services, Tokyo (Japan)] [and others

    1995-02-01

    Volatile halogenated organic compounds were determined in foods. Statistical treatment of the data for 13 sampled from 20 families living in suburban Tokyo (Saitama prefecture) indicated that the foods were contaminated by water pollution and/or substances introduced by the process of food production. Butter and margarine were contaminated by chlorinated ethylene, ethane, and related compounds released by dry cleaning and other operations. Soybean sprouts and tofu (soybean curd) contained chloroform and related trihalomethanes absorbed during the production process. 27 refs., 6 figs., 5 tabs.

  1. Non-volatile memories

    CERN Document Server

    Lacaze, Pierre-Camille

    2014-01-01

    Written for scientists, researchers, and engineers, Non-volatile Memories describes the recent research and implementations in relation to the design of a new generation of non-volatile electronic memories. The objective is to replace existing memories (DRAM, SRAM, EEPROM, Flash, etc.) with a universal memory model likely to reach better performances than the current types of memory: extremely high commutation speeds, high implantation densities and retention time of information of about ten years.

  2. Opportunity Analysis for Recovering Energy from Industrial Waste Heat and Emissions

    Energy Technology Data Exchange (ETDEWEB)

    Viswanathan, Vish V.; Davies, Richard W.; Holbery, Jim D.

    2006-04-01

    United States industry consumed 32.5 Quads (34,300 PJ) of energy during 2003, which was 33.1% of total U.S. energy consumption (EIA 2003 Annual Energy Review). The U.S. industrial complex yields valuable goods and products. Through its manufacturing processes as well as its abundant energy consumption, it supports a multi-trillion dollar contribution to the gross domestic product and provides millions of jobs in the U.S. each year. Industry also yields waste products directly through its manufacturing processes and indirectly through its energy consumption. These waste products come in two forms, chemical and thermal. Both forms of waste have residual energy values that are not routinely recovered. Recovering and reusing these waste products may represent a significant opportunity to improve the energy efficiency of the U.S. industrial complex. This report was prepared for the U.S. Department of Energy Industrial Technologies Program (DOE-ITP). It analyzes the opportunity to recover chemical emissions and thermal emissions from U.S. industry. It also analyzes the barriers and pathways to more effectively capitalize on these opportunities. A primary part of this analysis was to characterize the quantity and energy value of the emissions. For example, in 2001, the industrial sector emitted 19% of the U.S. greenhouse gases (GHG) through its industrial processes and emitted 11% of GHG through electricity purchased from off-site utilities. Therefore, industry (not including agriculture) was directly and indirectly responsible for emitting 30% of the U.S. GHG. These emissions were mainly comprised of carbon dioxide (CO2), but also contained a wide-variety of CH4 (methane), CO (carbon monoxide), H2 (hydrogen), NMVOC (non-methane volatile organic compound), and other chemicals. As part of this study, we conducted a survey of publicly available literature to determine the amount of energy embedded in the emissions and to identify technology opportunities to capture and

  3. Does implied volatility of currency futures option imply volatility of exchange rates?

    Science.gov (United States)

    Wang, Alan T.

    2007-02-01

    By investigating currency futures options, this paper provides an alternative economic implication for the result reported by Stein [Overreactions in the options market, Journal of Finance 44 (1989) 1011-1023] that long-maturity options tend to overreact to changes in the implied volatility of short-maturity options. When a GARCH process is assumed for exchange rates, a continuous-time relationship is developed. We provide evidence that implied volatilities may not be the simple average of future expected volatilities. By comparing the term-structure relationship of implied volatilities with the process of the underlying exchange rates, we find that long-maturity options are more consistent with the exchange rates process. In sum, short-maturity options overreact to the dynamics of underlying assets rather than long-maturity options overreacting to short-maturity options.

  4. Influence of storage conditions on the formation of some volatile compounds in white fortified wines (Vins doux naturels) during the aging process.

    Science.gov (United States)

    Cutzach, I; Chatonnet, P; Dubourdieu, D

    2000-06-01

    Sweet fortified wines, traditionally aged under strong oxidation conditions, have a characteristic aroma. An experimental study investigated the aging of white sweet fortified wines under various conditions. The development of various molecules, previously identified as characteristic of the aroma of this type of wine, was monitored by analysis. The development of these compounds during accelerated aging was affected by oxidation and the color of the wine. Aging in oak containers, variable storage temperatures, and variable modes of oxidation affect the formation of many of the volatile compounds responsible for the aging aroma of vins doux naturels (fortified wines). Furfural (1), 5-ethoxymethylfurfural (2), and sotolon (3) always reach concentrations above their perception thresholds in wood-aged wines, especially when new oak is used. The isomers of methyl-gamma-octalactone (4 and 5) are reliable indicators of aging in oak. Among the many identifiable volatile phenols, only the vanillin (7) content increases with aging, particularly if the container is made of wood and there is a high degree of oxidation. This molecule frequently reaches and even exceeds its perception threshold. We show here that vanillin and isomers of methyl-gamma-octalactone have a major impact on the aromas of fortified wines.

  5. Asymmetry Effects of shocks in Chinese Stock Markets Volatility

    DEFF Research Database (Denmark)

    Hou, Ai Jun

    2013-01-01

    The unique characteristics of the Chinese stock markets make it difficult to assume a particular distribution for innovations in returns and the specification form of the volatility process when modelling return volatility with the parametric GARCH family models. This paper therefore applies a ge...... nonparametric model demonstrates a better performance for return volatility forecasts, particularly for the out-of-sample forecast. The results from this paper have important implications in risk management, portfolio selection, and hedging strategy.......The unique characteristics of the Chinese stock markets make it difficult to assume a particular distribution for innovations in returns and the specification form of the volatility process when modelling return volatility with the parametric GARCH family models. This paper therefore applies...... a generalized additive nonparametric smoothing technique to examine the volatility of the Chinese stock markets. The empirical results indicate that an asymmetric effect of negative news exists in the Chinese stock markets. Furthermore, compared with other parametric models, the generalized additive...

  6. A Jump-Diffusion Model with Stochastic Volatility and Durations

    DEFF Research Database (Denmark)

    Wei, Wei; Pelletier, Denis

    Market microstructure theories suggest that the durations between transactions carry information about volatility. This paper puts forward a model featuring stochastic volatility, stochastic conditional duration, and jumps to analyze high frequency returns and durations. Durations affect price...... jumps in two ways: as exogenous sampling intervals, and through the interaction with volatility. We adopt a bivariate Ornstein-Ulenbeck process to model intraday volatility and conditional duration. We develop a MCMC algorithm for the inference on irregularly spaced multivariate processes with jumps....... The algorithm provides smoothed estimates of the latent variables such as spot volatility, conditional duration, jump times, and jump sizes. We apply this model to IBM data and find that volatility and conditional duration are interdependent. We also find that jumps play an important role in return variation...

  7. Silver-palladium braze alloy recovered from masking materials

    Science.gov (United States)

    Cierniak, R.; Colman, G.; De Carlo, F.

    1966-01-01

    Method for recovering powdered silver-palladium braze alloy from an acrylic spray binder and rubber masking adhesive used in spray brazing is devised. The process involves agitation and dissolution of masking materials and recovery of suspended precious metal particles on a filter.

  8. Recovering Place: On the Agency

    Directory of Open Access Journals (Sweden)

    Joern Langhorst

    2012-12-01

    Full Text Available Based on the author’s ongoing involvement in the recovery after hurricane Katrina in New Orleans, and the Lower Ninth Ward neighbourhood in particular, this paper discusses the implications of alternative strategies and tactics involved in the recovery, restoration and rebuilding of post-disaster landscapes. It emphasises that the recovery and rebuilding of community is as important as physical restoration. The empowerment of disaster-affected communities is posited as a central element, in particular, because disasters often reveal long-standing underlying dysfunctions and uneven development patterns as important factors disproportionally affecting communities that were already victimised and marginalised. Design and planning approaches that gain the trust of local residents can reveal hidden, suppressed and alternative narratives and histories central to understanding the processes leading up to the disaster and to the development of viable and sustainable future scenarios. The active participation of traumatised communities is critical to an inclusive discourse on their future, allowing them to become co-authors of the landscapes and places they inhabit instead of victims of hegemonial agendas that created pre-disaster conditions in the first place. The paper discusses a modest spatial intervention in the Lower Ninth Ward and its impacts as an example of the agency of landscape in processes of cultural change. It discusses the instrumentality of a truly public space in a critical location in asserting the viability of a post-disaster neighbourhood and in changing the discourses on human–environment relationships to facilitate a sustainable future in a landscape shaped by challenging social and environmental dynamics.

  9. Asymmetry Effects of shocks in Chinese Stock Markets Volatility

    DEFF Research Database (Denmark)

    Hou, Ai Jun

    2013-01-01

    The unique characteristics of the Chinese stock markets make it difficult to assume a particular distribution for innovations in returns and the specification form of the volatility process when modelling return volatility with the parametric GARCH family models. This paper therefore applies...... a generalized additive nonparametric smoothing technique to examine the volatility of the Chinese stock markets. The empirical results indicate that an asymmetric effect of negative news exists in the Chinese stock markets. Furthermore, compared with other parametric models, the generalized additive...

  10. Dynamic headspace analyses of residual volatiles in pharmaceuticals.

    Science.gov (United States)

    Wampler, T P; Bowe, W A; Levy, E J

    1985-02-01

    Pharmaceutical preparations may be assayed for volatile organic compounds by purging them with a stream of inert carrier gas and collecting the organics onto a suitable sorbent material, from which they may be backflushed to a gas chromatograph. Compared to solvent extraction, the process offers advantages of increased sensitivity, ease of automation, and elimination of the solvent peak. Examples are given of three major sources of volatiles in pharmaceuticals, with the development of a method for quantitating the volatiles using an internal standard.

  11. Volatile components and continental material of planets

    Science.gov (United States)

    Florenskiy, K. P.; Nikolayeva, O. V.

    1986-01-01

    It is shown that the continental material of the terrestrial planets varies in composition from planet to planet according to the abundances and composition of true volatiles (H20, CO2, etc.) in the outer shells of the planets. The formation of these shells occurs very early in a planet's evolution when the role of endogenous processes is indistinct and continental materials are subject to melting and vaporizing in the absence of an atmosphere. As a result, the chemical properties of continental materials are related not only to fractionation processes but also to meltability and volatility. For planets retaining a certain quantity of true volatile components, the chemical transformation of continental material is characterized by a close interaction between impact melting vaporization and endogeneous geological processes.

  12. Chemical properties of ω-3 fortified gels made of protein isolate recovered with isoelectric solubilisation/precipitation from whole fish.

    Science.gov (United States)

    Tahergorabi, Reza; Beamer, Sarah K; Matak, Kristen E; Jaczynski, Jacek

    2013-08-15

    Protein isolate was recovered from whole gutted fish using isoelectric solubilisation/precipitation (ISP). The objective was to determine chemical properties of heat-set gels made of the ISP protein isolate fortified with ω-3 polyunsaturated fatty acids (PUFAs)-rich oils (flaxseed, fish, algae, krill, and blend). The extent of the PUFAs increase, ω-6/ω-3 FAs and unsaturated/saturated FAs ratios, and the indices of thrombogenicity and atherogenicity depended on specific ω-3 PUFAs-rich oil used to fortify protein isolate gels. Lipid oxidation in ω-3 PUFAs fortified gels was minimal, although greater (Pgels (without ω-3 PUFAs fortification). However, all gels were in the slightly rancid, but acceptable range. The commonly used thiobarbituric-acid-reactive-substances (TBARS) assay to determine lipid oxidation in seafood may be inaccurate for samples containing krill oil due to its red pigment, astaxanthin. Protein degradation (total-volatile-basic-nitrogen) was greater (Pgels than control gels. However, all gels were considerably below the acceptability threshold for protein degradation. The shear stress of ω-3 PUFAs fortified gels was generally greater than the control gels and the shear strain was generally unchanged. This study demonstrates that ω-3 PUFAs fortification of protein isolates recovered with ISP from fish processing by-products or whole fish has potential application in the development of functional foods.

  13. Hydrometallurgical route to recover molybdenum, nickel, cobalt and aluminum from spent hydrotreating catalysts in sulphuric acid medium.

    Science.gov (United States)

    Valverde, Ivam Macedo; Paulino, Jéssica Frontino; Afonso, Julio Carlos

    2008-12-30

    This work describes a hydrometallurgical route for processing spent commercial catalysts (CoMo and NiMo/Al2O3), for recovering the active phase and support components. They were initially pre-oxidized (500 degrees C, 5h) in order to eliminate coke and other volatile species present. Pre-oxidized catalysts were dissolved in H2SO4 (9molL-1) at approximately 90 degrees C, and the remaining residues separated from the solution. Molybdenum was recovered by solvent extraction using tertiary amines. Alamine 304 presented the best performance at pH around 1.8. After this step, cobalt (or nickel) was separated by adding aqueous ammonium oxalate in the above pH. Before aluminum recovery, by adding NaOH to the acid solution, phosphorus (H2PO4-) was removed by passing the liquid through a strong anion exchange column. Final wastes occur as neutral and colorless sodium sulphate solutions and the insoluble solid in the acid leachant. The hydrometallurgical route presented in this work generates less final aqueous wastes, as it is not necessary to use alkaline medium during the metal recovery steps. The metals were isolated in very high yields (>98wt.%).

  14. Topographic quantitative EEG amplitude in recovered alcoholics.

    Science.gov (United States)

    Pollock, V E; Schneider, L S; Zemansky, M F; Gleason, R P; Pawluczyk, S

    1992-05-01

    Topographic measures of electroencephalographic (EEG) amplitude were used to compare recovered alcoholics (n = 14) with sex- and age-matched control subjects. Delta, alpha, and beta activity did not distinguish the groups, but regional differences in theta distribution did. Recovered alcoholics showed more uniform distributions of theta amplitudes in bilateral anterior and posterior regions compared with controls. Because a minimum of 5 years had elapsed since the recovered alcoholic subjects fulfilled DSM-III-R criteria for alcohol abuse or dependence, it is unlikely these EEG theta differences reflect the effects of withdrawal.

  15. Spirocyclic aromatic hydrocarbon-based organic nanosheets for eco-friendly aqueous processed thin-film non-volatile memory devices.

    Science.gov (United States)

    Lin, Zong-Qiong; Liang, Jin; Sun, Peng-Ju; Liu, Feng; Tay, Yee-Yan; Yi, Ming-Dong; Peng, Kun; Xia, Xian-Hai; Xie, Ling-Hai; Zhou, Xin-Hui; Zhao, Jian-Feng; Huang, Wei

    2013-07-19

    Supramolecular steric hindrance designs make pyrene-functionalized spiro[fluorene-9,7'-dibenzo[c,h]acridine]-5'-one (Py-SFDBAO) assemble into 2D nanostructures that facilitate aqueous phase large-area synthesis of high-quality and uniform crystalline thin films. Thin-film diodes using aqueous nanosheets as active layers exhibit a non-volatile bistable electrical switching feature with ON/OFF ratios of 6.0 × 10(4) and photoswitching with conductive gains of 10(2) -10(3). Organic nanosheets are potentially key components for eco-friendly aqueous dispersed organic nano-inks in the application of printed and flexible electronics.

  16. Tetracycline removal and effect on the formation and degradation of extracellular polymeric substances and volatile fatty acids in the process of hydrogen fermentation.

    Science.gov (United States)

    Hou, Guangying; Hao, Xiaoyan; Zhang, Rui; Wang, Jing; Liu, Rutao; Liu, Chunguang

    2016-07-01

    Many research indicate antibiotics show adverse effect on methane fermentation, while few research focus on their effect on hydrogen fermentation. The present study aimed to gain insight of the effect of antibiotics on hydrogen fermentation with waste sludge and corn straw as substrate. For this purpose, tetracycline, as a model, was investigated with regard to tetracycline removal, hydrogen production, interaction with extracellular polymeric substances (EPSs) of substrate and volatile fatty acids (VFAs) on concentration and composition. Results show that tetracycline could be removed efficiently by hydrogen fermentation, and relative low-dose tetracycline (200mg/l) exposure affects little on hydrogen production. While tetracycline exposure could change hydrogen fermentation from butyric acid-type to propionic acid-type depending on tetracycline level. Based upon three-dimensional excitation-emission matrix fluorescence spectroscopy and UV-vis tetracycline changed the component and content of EPSs, and static quenching was the main mechanism between EPSs with tetracycline.

  17. Determination of refractive and volatile elements in sediment using laser ablation inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Duodu, Godfred Odame [School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), 2 George St, 4001, QLD (Australia); Goonetilleke, Ashantha [School of Civil Engineering and Built Environment, Science and Engineering Faculty, Queensland University of Technology (QUT), 2 George St, 4001, QLD (Australia); Allen, Charlotte [Institute for Future Environments, Queensland University of Technology (QUT), 2 George St, 4001, QLD (Australia); Ayoko, Godwin A., E-mail: g.ayoko@qut.edu.au [School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), 2 George St, 4001, QLD (Australia)

    2015-10-22

    Wet-milling protocol was employed to produce pressed powder tablets with excellent cohesion and homogeneity suitable for laser ablation (LA) analysis of volatile and refractive elements in sediment. The influence of sample preparation on analytical performance was also investigated, including sample homogeneity, accuracy and limit of detection. Milling in volatile solvent for 40 min ensured sample is well mixed and could reasonably recover both volatile (Hg) and refractive (Zr) elements. With the exception of Cr (−52%) and Nb (+26%) major, minor and trace elements in STSD-1 and MESS-3 could be analysed within ±20% of the certified values. Comparison of the method with total digestion method using HF was tested by analysing 10 different sediment samples. The laser method recovers significantly higher amounts of analytes such as Ag, Cd, Sn and Sn than the total digestion method making it a more robust method for elements across the periodic table. LA-ICP-MS also eliminates the interferences from chemical reagents as well as the health and safety risks associated with digestion processes. Therefore, it can be considered as an enhanced method for the analysis of heterogeneous matrices such as river sediments. - Highlights: • Wet milling was used to produce pressed tablet sediment for LA-ICP-MS analysis. • Milling was effective for refractive elements with narrow range of particle size. • This is the first use of LA-ICP-MS for Hg analysis in sediment samples. • Acceptable accuracy and precision were obtained for most of the elements studied. • Detection limits down to parts per trillion were observed for some elements.

  18. Microwave Extraction of Volatiles for Mars Science and ISRU

    Science.gov (United States)

    Ethridge, Edwin C.; Kaulker, William F.

    2012-01-01

    The greatest advantage of microwave heating for volatiles extraction is that excavation can be greatly reduced. Surface support operations would be simple consisting of rovers with drilling capability for insertion of microwaves down bore holes to heat at desired depths. The rovers would also provide support to scientific instruments for volatiles analysis and for volatiles collection and storage. The process has the potential for a much lower mass and a less complex system than other in-situ processes. Microwave energy penetrates the surface heating within with subsequent sublimation of water or decomposition of volatile containing minerals. On Mars the volatiles should migrate to the surface to be captured with a cold trap. The water extraction and transport process coupled with atmospheric CO2 collection could readily lead to a propellant production process, H2O + CO2 yields CH4 + O2.

  19. Understanding Interest Rate Volatility

    DEFF Research Database (Denmark)

    Volker, Desi

    This thesis is the result of my Ph.D. studies at the Department of Finance of the Copenhagen Business School. It consists of three essays covering topics related to the term structure of interest rates, monetary policy and interest rate volatility. The rst essay, \\Monetary Policy Uncertainty...... and Interest Rates", examines the role of monetary policy uncertainty on the term structure of interest rates. The second essay, \\A Regime-Switching A ne Term Structure Model with Stochastic Volatility" (co-authored with Sebastian Fux), investigates the ability of the class of regime switching models...... with and without stochastic volatility to capture the main stylized features of U.S. interest rates. The third essay, \\Variance Risk Premia in the Interest Rate Swap Market", investigates the time-series and cross-sectional properties of the compensation demanded for holding interest rate variance risk. The essays...

  20. METHOD FOR RECOVERING URANIUM FROM OILS

    Science.gov (United States)

    Gooch, L.H.

    1959-07-14

    A method is presented for recovering uranium from hydrocarbon oils, wherein the uranium is principally present as UF/sub 4/. According to the invention, substantially complete removal of the uranium from the hydrocarbon oil may be effected by intimately mixing one part of acetone to about 2 to 12 parts of the hydrocarbon oil containing uranium and separating the resulting cake of uranium from the resulting mixture. The uranium in the cake may be readily recovered by burning to the oxide.

  1. Enhanced Mixed Feedstock Processing Using Ionic Liquids

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, Blake A [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

    2016-10-22

    Biomass pretreatment using certain ionic liquids (ILs) is very efficient, generally producing a substrate that is amenable to saccharification with fermentable sugar yields approaching theoretical limits. Although promising, several challenges must be addressed before IL pretreatment technology becomes commercially viable. Once of the most significant challenges is the affordable and scalable recovery and recycle or the IL itself. Pervaporation is a highly selective and scalable membrane separation process for quantitatively recovering volatile solutes or solvents directly from non-volatile solvents that could prove more versatile for IL dehydration than traditional solvent extraction processes, as well as efficient and energetically more advantageous than standard evaporative techniques. In this study we evaluated a commercially available pervaporation system for IL dehydration and recycling as part of an integrated IL pretreatment process using 1-ethyl-3-methylimidazolium acetate ([C2C1Im][OAc]) that has been proven to be very effective as a biomass pretreatment solvent. We demonstrate that >99.9 wt% [C2C1Im][OAc] can be recovered from aqueous solution and recycled at least five times. A preliminary techno-economic analysis validated the promising role of pervaporation in improving overall biorefinery process economics, especially in the case where other IL recovery technologies might lead to significant losses. These findings establish the foundation for further development of pervaporation as an effective method of recovering and recycling ILs using a commercially viable process technology.

  2. Detecting instability in the volatility of carbon prices

    Energy Technology Data Exchange (ETDEWEB)

    Chevallier, Julien [Univ. Paris Dauphine (France)

    2011-01-15

    This article investigates the presence of outliers in the volatility of carbon prices. We compute three different measures of volatility for European Union Allowances, based on daily data (EGARCH model), option prices (implied volatility), and intraday data (realized volatility). Based on the methodology developed by Zeileis et al. (2003) and Zeileis (2006), we detect instability in the volatility of carbon prices based on two kinds of tests: retrospective tests (OLS-/Recursive-based CUSUM processes, F-statistics, and residual sum of squares), and forward-looking tests (by monitoring structural changes recursively or with moving estimates). We show evidence of strong shifts mainly for the EGARCH and IV models during the time period. Overall, we suggest that yearly compliance events, and growing uncertainties in post-Kyoto international agreements, may explain the instability in the volatility of carbon prices. (author)

  3. The multivariate supOU stochastic volatility model

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole; Stelzer, Robert

    structure of the volatility, the log returns, as well as their "squares" are discussed in detail. Moreover, we give several examples in which long memory effects occur and study how the model as well as the simple Ornstein-Uhlenbeck type stochastic volatility model behave under linear transformations......Using positive semidefinite supOU (superposition of Ornstein-Uhlenbeck type) processes to describe the volatility, we introduce a multivariate stochastic volatility model for financial data which is capable of modelling long range dependence effects. The finiteness of moments and the second order...

  4. A study on the process and activation of recovering nisin from the fermentation broth by foam separation%泡沫分离发酵液中乳链菌肽的工艺和活性研究

    Institute of Scientific and Technical Information of China (English)

    刘云菲; 胡滨; 吴兆亮

    2012-01-01

    Nisin is a kind of antimicrobial peptides widely used but easy to lose activation, and it is difficult to separate and purify. In this paper, the foam separation technology is used for the recovering of nisin from the fermentation broth. The effect of the gas velocity, the temperature and the gas-distribution aperture to enrichment ratio, recovery rate and in-activation rate of nisin is discussed. The experimental results show that with the gas velocity increasing, the recovery rate increases, and the enrichment ratio and the nisin inactivation rate decrease; with the temperature increasing, the enrichment ratio and the nisin inactivation rate increase, and the recovery rate decreases; with the gas-distributor aperture augments, bubbles become larger, the enrichment ratio and the nisin inactivation rate increase, and the recovery rate decreases.%乳链菌肽(nisin)是一种用途广泛但容易失活的抗菌肽,分离纯化难度大.本文以发酵液为实验物系,利用泡沫分离技术从中分离纯化nisin,研究了气速、温度、分布器孔径对实验物系的影响.实验结果表明,随着气速的增加,泡沫分离乳链菌肽的富集比减小,回收率增大,nisin 的失活率逐渐减小 ;随着温度的升高,泡沫分离乳链菌肽的富集比增加,回收率降低,nisin的失活率增大 ;随分布器孔径增大,气泡变大,泡沫分离乳链菌肽的富集比增大,回收率降低,nisin的失活率增大.

  5. Analysis of Volatile Chemical Constituents in Vinegar-Processed Schisandrae Sphenantherae Fructus and Vinegar-Processed Schisandrae Chinesis Fructus by HS-SPME-GC-MS%HS-SPME-GC-MS联用分析醋制南北五味子中挥发性成分

    Institute of Scientific and Technical Information of China (English)

    叶欣; 卢金清; 曹利; 林杰; 万丽娟

    2016-01-01

    Objective:To analyze and compare the volatile components in vinegar-processed schisandrae sphenantherae fructus and vinegar-processed schisandrae chinesis fructus.Methods:The volatile components in vinegar-processed schisandrae sphenantherae fruc-tus and vinegar-processed schisandrae chinesis fructus were extracted by headspace solid phase-microextraction (HS-SPME) and quali-tatively analyzed by GC-MS.Results:Totally 20 kinds of constituents were identified from vinegar-processed schisandra sphenanthera fructus, which accounted for 99.55%of the total volatile components , and totally 21 kinds of constituents were identified from vinegar-processed schisandra sphenanthera fructus, which accounted for 99.90% of the total volatile components .Conclusion: The type and content of volatile components in vinegar-processed schisandrae sphenantherae fructus and vinegar-processed schisandrae chinesis fructus are quite different , and the study can provide scientific basis for the two traditional Chinese medicinal materials .%目的:分析和比较醋制南北五味子挥发性成分。方法:采用顶空固相微萃取法( HS-SPME)萃取醋制南北五味子中挥发性成分,结合GC-MS法对其挥发性成分进行分析。结果:从醋制南五味子中鉴定出20种化学成分,从醋制北五味子中鉴定出21种化学成分,分别占各自挥发性成分总量的99.55%和99.90%。结论:醋制南北五味子的挥发性成分在种类和含量上差异较大,为快速鉴定醋制南北五味子提供科学依据。

  6. Hydrometallurgical route to recover molybdenum, nickel, cobalt and aluminum from spent hydrotreating catalysts in acid medium; Rota hidrometalurgica de recuperacao de molibdenio, cobalto, niquel e aluminio de catalisadores gastos de hidrotratamento em meio acido

    Energy Technology Data Exchange (ETDEWEB)

    Valverde Junior, Ivam Macedo; Paulino, Jessica Frontino; Afonso, Julio Carlos [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Quimica. Dept. de Quimica Analitica]. E-mail: julio@iq.ufrj.br

    2008-07-01

    This work describes a hydrometallurgical route for processing spent commercial catalysts (CoMo and NiMo/Al{sub 2}O{sub 3}). Samples were preoxidized (500 deg C, 5 h) in order to eliminate coke and other volatile species present. The calcined solid was dissolved in concentrated H{sub 2}SO{sub 4} and water (1:1 vol/vol) at 90 de C; the insoluble matter was separated from the solution. Molybdenum was recovered by solvent extraction using tertiary amines at pH around 1.8. Cobalt (or nickel) was separated by addition of aqueous ammonium oxalate at the above pH. Phosphorus was removed by passing the liquid through a strong anion exchange column. Aluminum was recovered by neutralizing the solution with NaOH. The route presented in this work generates less final aqueous wastes because it is not necessary to use alkaline medium during the metal recovery steps. (author)

  7. Changes of volatile composition during fumigating process of Liangzhou fumigated vinegar%凉州熏醋熏醅前后挥发性成分的变化

    Institute of Scientific and Technical Information of China (English)

    韩庆辉; 贠建民; 宋勇强; 文玉

    2012-01-01

    采用顶空固相微萃取技术(SPME)和气质联用技术(GC-MS)相结合的方法对凉州熏醋熏醅前后的挥发性成分进行了分析。结果表明,凉州熏醋熏醅前后的挥发性成分分别为58种和57种,主要包括醇类、酸类、酯类、醛类、酮类、杂环类、烃类七大类化合物;凉州熏醋在熏醅前的主要挥发性成分为乙酸铵(18.223%)、乙酸乙酯(15.853%)、乙酸(15.236%)、3-羟基-2-丁酮(19.532%)等;熏醅后为乙酸铵(49.959%)、乙酸乙酯(5.352%)、3-羟基-2-丁酮(9.530%)、糠醛(12.007%)等。初步探明了凉州熏醋熏醅前、后主要挥发性成分的变化。%The volatile components of Liangzhou fumigated vinegar before and after fumigating were inspected by headspace solid phase micro-extraction(SPME) and gas chromatography-mass spectrum(GC-MS) technique.The results showed that 58 and 57 kinds of compounds existed in two samples respectively,the major compounds were alcohols,acids,esters,aldehydes,ketones,herterocylics and alkanes in both materials.The major volatile compounds of liangzhou fumigated materials before fumigating were ammonium acetate(18.223%),ethyl acetate(15.853%),acetic acid(15.236%) and 3-hydroxybu-2-tanone(19.532%).The compounds after fumigating were ammonium acetate(49.959%),ethyl,acetate(5.352%),3-hydroxybu-2-tanone(9.530%),furfural(12.007%).Preliminary proved the changes of flavor substancesin roasted materials of liangzhou fumigated vinegar before and after fumigating.

  8. Option Valuation with Observable Volatility and Jump Dynamics

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Feunou, Bruno; Jeon, Yoontae

    Under very general conditions, the total quadratic variation of a jump-diffusion process can be decomposed into diffusive volatility and squared jump variation. We use this result to develop a new option valuation model in which the underlying asset price exhibits volatility and jump intensity dy...

  9. 蒸馏-萃取耦合法提取川芎挥发油的工艺优化研究%Process optimization study of coupled method of distillation-extraction for volatile oil of Ligusticum Chuanxiong Hort

    Institute of Scientific and Technical Information of China (English)

    赵引利; 何燕宁; 胡春兰; 杨冬丽; 张东阁; 杨宇杰; 王春民; 雒佳莉

    2015-01-01

    Objective To further optimize coupled method of distillation-extraction for volatile oil of Ligusticum Chuanxiong Hort.. Methods Distillation and solvent extraction method were coupled to extract volatile oil of Ligusticum Chuanxiong Hort..Recovery rate of ligustilide was selected as an indicator to optimize the separation and purification of volatile oil of Ligusticum Chuanxiong Hort.,which was mixed with extraction agent.The content of ligustilide was deter-mined by gas chromatography.AT-5 quartz capillary at size of 30 mí0.32 mmí0.25 μm was selected as capillary-col-umn chromatography.The basic conditions were flame ionization detector (FID),temperature of injection port being 250℃, temperature of detector being 250℃,and temperature programming. Results The optimized extraction process was paraffin wax solution extracted once by 1 ml ethyl alcohol,and 5 times by 0.5 ml ethyl alcohol,and salted out by 1.5 times of 30% sodium chloride solution before obtaining volatile oil of Ligusticum Chuanxiong Hort.. Conclusion The opti-mized coupled method of distillation-extraction process is stable and can be applied to extract volatile oil of Ligusticum Chuanxiong Hort..%目的:对蒸馏原萃取耦合法进行进一步优化,用于提取川芎挥发油。方法将蒸馏法与溶剂萃取法耦合用于提取川芎挥发油,以藁本内酯回收率为指标优选混有萃取剂的川芎挥发油的分离、纯化过程。用气相色谱法检测藁本内酯含量,采用AT-5石英毛细管色谱柱(30 m×0.32 mm×0.25μm);FID检测器;进样口温度:250℃,检测器温度:250℃;程序升温。结果确定优化后的提取工艺,即蒸馏-萃取所得川芎挥发油的石蜡溶液经1 ml乙醇萃取1次,0.5 ml乙醇萃取5次,1.5倍量30%NaCl水溶液盐析等得到川芎挥发油。结论优化后的蒸馏原萃取耦合法工艺稳定,可以用于提取川芎挥发油。

  10. Dynamic Volatility Arbitrage

    DEFF Research Database (Denmark)

    Dorn, Jochen

    concepts, next to nothing is known about position reverting strategies and how, and -even more important- in which context they are applied in practice. In the recent market downturn only one sector generated signicant profits for the leading investment banks: Volatility trading activities, namely on Forex...

  11. Stock markets liberalization affects volatility?

    OpenAIRE

    Ioan Alin NISTOR; Maria-Lenuţa CIUPAC-ULICI; GHERMAN Mircea-Cristian

    2012-01-01

    Regarding the impact of liberalization, the results show that, in general, market opening is accompanied by a significant increase in market volatility. In particular, volatility tends to decrease due to large capital inflows and domestic growth.The study analyzes the impact of stock market liberalization on volatility in six emerging stock markets by using GARCH methodology. Theory on the effects of financial liberalization on volatility has been ambiguous, and empirical work has yielded con...

  12. The exploitation of volatile oil

    Institute of Scientific and Technical Information of China (English)

    MENG Teng; ZHANG Da; TENG Xiangjin; LINing; HAO Zaibin

    2007-01-01

    Rose is a kind of favorite ornamental plant. This article briefly introduced the cultivation and the use of rose around the world both in ancient time and nowadays. Today, volatile oil becomes the mainstream of the rose industry. People pay attention to the effect of volatile oil; meanwhile, they speed up their research on extracting volatile oil and the ingredients.

  13. Plant volatiles and the environment

    NARCIS (Netherlands)

    Loreto, F.; Dicke, M.; Schnitzler, J.P.; Turlings, T.C.J.

    2014-01-01

    Volatile organic compounds emitted by plants represent the largest part of biogenic volatile organic compounds (BVOCs) released into our atmosphere. Plant volatiles are formed through many biochemical pathways, constitutively and after stress induction. In recent years, our understanding of the func

  14. Development and simulation of a novel oil absorption process for recovering ethylene from refinery dry gas%油吸收法回收干气中乙烯新工艺的开发与模拟

    Institute of Scientific and Technical Information of China (English)

    李鑫钢; 王珏; 丛山; 罗小波; 王美宏; 李洪

    2016-01-01

    Oil refineries dry gases contain ethylene and other valuable raw material.However,those dry gases are often lined into the flare system to be burned directly,which results in a waste of resources.Current oil absorption methods are difficult to get polymerization grade C2 components and that limits their range of use.A novel oil absorption method using C5 as absorbent was developed to recover polymerization grade C2 components.Then a single factor analysis of the recovery of C2 components and energy consumption was analyzed for different cases according to different system pressure,temperature,absorbent flowrate and theoretical stage numbers of all columns.The appropriate range of those factors are 3-3.2 MPa,-20-10℃,15-20 t/h,20,14,20 for absorption column,desorption column and distillation column.Then an orthogonal analysis of temperature,pressure and absorbent flowrate was conducted,which showed that the order of influencing recovery was absorbent flowrate >temperature >pressure,the order of influencing energy consumption was pressure >temperature >absorbent flowrate.%炼厂干气中含有乙烯等有价值的气体,目前多以燃烧为主,造成资源浪费.现有的油吸收法获得的C2 产品纯度低,应用范围受到限制.为了获得高纯度的C2 产品,文章开发了一种以C5 作为吸收剂回收干气中高纯度C2的三塔流程.通过单因素分析研究了吸收压力、吸收温度、吸收剂流量、各塔理论板数等对C2 回收率、能耗的影响.结果表明:单位能耗较低时的吸收压力为3—3.2 MPa,吸收温度为-20—-10℃,吸收剂流量为15—20 t/h,吸收塔、解吸塔、精馏塔理论板数分别为20,14,20.通过多因素正交模拟分析发现,对C2 回收率影响的因素大小顺序为吸收剂流量>吸收温度>吸收压力;对能耗影响的因素大小为吸收压力>吸收温度>吸收剂流量.

  15. Volume, Volatility and Public News Announcements

    DEFF Research Database (Denmark)

    Bollerslev, Tim; Li, Jia; Xue, Yuan

    We provide new empirical evidence for the way in which financial markets process information. Our results are based on high-frequency intraday data along with new econometric techniques for making inference on the relationship between trading intensity and spot volatility around public news...

  16. Explaining output volatility: The case of taxation

    DEFF Research Database (Denmark)

    Posch, Olaf

    the second moment of output growth rates without (long-run) effects on the first moment. Taking the model to the data, we exploit observed heterogeneity patterns to estimate effects of tax rates on macro volatility using panel estimation, explicitly modeling the unobserved variance process. We find a strong...

  17. Ergonomic analysis jobs in recovered factories.

    Science.gov (United States)

    Cuenca, Gabriela; Zotta, Gastón

    2012-01-01

    With the advent of the deep economic crisis in Argentina on 2001, the recovery of companies through to the creation of the Cooperatives Working Self-Management or Factories Recovered by its workers was constituted as one of the ways in which the salaried disobeyed the increasing unemployment. When the companies turn into recovered factories they tend to leave of side practices that have been seen like imposed by the previous organization and not understanding them as a primary condition for the execution of his tasks. Safety and ergonomics are two disciplines that are no longer considered relevant to the daily work. Therefore this investigation aims to revalue, undergo semantic to give back to a place in every organization analyzed. This research developed a self-diagnostic tool for working conditions, and the environment, present in the recovered factories.

  18. Volatile species retention during metallic fuel casting

    Science.gov (United States)

    Fielding, Randall S.; Porter, Douglas L.

    2013-10-01

    Metallic nuclear fuels are candidate transmutation fuel forms for advanced fuel cycles. Through the operation of the Experimental Breeder Reactor II metallic nuclear fuels have been shown to be robust and easily manufactured. However, concerns have been raised concerning loss of americium during the casting process because of its high vapor pressure. In order to address these concerns a gaseous diffusion model was developed and a series of experiments using both manganese and samarium as surrogates for americium were conducted. The modeling results showed that volatility losses can be controlled to essentially no losses with a modest overpressure. Experimental results also showed volatile species retention down to no detectable losses through overpressure, and although the loss values varied from the model results the same trend was seen. Based on these results it is very probable that americium losses through volatility can be controlled to no detectable losses through application of a modest overpressure during casting.

  19. Medication errors recovered by emergency department pharmacists.

    Science.gov (United States)

    Rothschild, Jeffrey M; Churchill, William; Erickson, Abbie; Munz, Kristin; Schuur, Jeremiah D; Salzberg, Claudia A; Lewinski, Daniel; Shane, Rita; Aazami, Roshanak; Patka, John; Jaggers, Rondell; Steffenhagen, Aaron; Rough, Steve; Bates, David W

    2010-06-01

    We assess the impact of emergency department (ED) pharmacists on reducing potentially harmful medication errors. We conducted this observational study in 4 academic EDs. Trained pharmacy residents observed a convenience sample of ED pharmacists' activities. The primary outcome was medication errors recovered by pharmacists, including errors intercepted before reaching the patient (near miss or potential adverse drug event), caught after reaching the patient but before causing harm (mitigated adverse drug event), or caught after some harm but before further or worsening harm (ameliorated adverse drug event). Pairs of physician and pharmacist reviewers confirmed recovered medication errors and assessed their potential for harm. Observers were unblinded and clinical outcomes were not evaluated. We conducted 226 observation sessions spanning 787 hours and observed pharmacists reviewing 17,320 medications ordered or administered to 6,471 patients. We identified 504 recovered medication errors, or 7.8 per 100 patients and 2.9 per 100 medications. Most of the recovered medication errors were intercepted potential adverse drug events (90.3%), with fewer mitigated adverse drug events (3.9%) and ameliorated adverse drug events (0.2%). The potential severities of the recovered errors were most often serious (47.8%) or significant (36.2%). The most common medication classes associated with recovered medication errors were antimicrobial agents (32.1%), central nervous system agents (16.2%), and anticoagulant and thrombolytic agents (14.1%). The most common error types were dosing errors, drug omission, and wrong frequency errors. ED pharmacists can identify and prevent potentially harmful medication errors. Controlled trials are necessary to determine the net costs and benefits of ED pharmacist staffing on safety, quality, and costs, especially important considerations for smaller EDs and pharmacy departments. Copyright (c) 2009 American College of Emergency Physicians

  20. Silicon isotopes in angrites and volatile loss in planetesimals

    Science.gov (United States)

    Moynier, Frédéric; Savage, Paul S.; Badro, James; Barrat, Jean-Alix

    2014-01-01

    Inner solar system bodies, including the Earth, Moon, and asteroids, are depleted in volatile elements relative to chondrites. Hypotheses for this volatile element depletion include incomplete condensation from the solar nebula and volatile loss during energetic impacts. These processes are expected to each produce characteristic stable isotope signatures. However, processes of planetary differentiation may also modify the isotopic composition of geochemical reservoirs. Angrites are rare meteorites that crystallized only a few million years after calcium–aluminum-rich inclusions and exhibit extreme depletions in volatile elements relative to chondrites, making them ideal samples with which to study volatile element depletion in the early solar system. Here we present high-precision Si isotope data that show angrites are enriched in the heavy isotopes of Si relative to chondritic meteorites by 50–100 ppm/amu. Silicon is sufficiently volatile such that it may be isotopically fractionated during incomplete condensation or evaporative mass loss, but theoretical calculations and experimental results also predict isotope fractionation under specific conditions of metal–silicate differentiation. We show that the Si isotope composition of angrites cannot be explained by any plausible core formation scenario, but rather reflects isotope fractionation during impact-induced evaporation. Our results indicate planetesimals initially formed from volatile-rich material and were subsequently depleted in volatile elements during accretion. PMID:25404309

  1. Silicon isotopes in angrites and volatile loss in planetesimals.

    Science.gov (United States)

    Pringle, Emily A; Moynier, Frédéric; Savage, Paul S; Badro, James; Barrat, Jean-Alix

    2014-12-02

    Inner solar system bodies, including the Earth, Moon, and asteroids, are depleted in volatile elements relative to chondrites. Hypotheses for this volatile element depletion include incomplete condensation from the solar nebula and volatile loss during energetic impacts. These processes are expected to each produce characteristic stable isotope signatures. However, processes of planetary differentiation may also modify the isotopic composition of geochemical reservoirs. Angrites are rare meteorites that crystallized only a few million years after calcium-aluminum-rich inclusions and exhibit extreme depletions in volatile elements relative to chondrites, making them ideal samples with which to study volatile element depletion in the early solar system. Here we present high-precision Si isotope data that show angrites are enriched in the heavy isotopes of Si relative to chondritic meteorites by 50-100 ppm/amu. Silicon is sufficiently volatile such that it may be isotopically fractionated during incomplete condensation or evaporative mass loss, but theoretical calculations and experimental results also predict isotope fractionation under specific conditions of metal-silicate differentiation. We show that the Si isotope composition of angrites cannot be explained by any plausible core formation scenario, but rather reflects isotope fractionation during impact-induced evaporation. Our results indicate planetesimals initially formed from volatile-rich material and were subsequently depleted in volatile elements during accretion.

  2. Crude ethanolic extract from spent coffee grounds: Volatile and functional properties.

    Science.gov (United States)

    Page, Julio C; Arruda, Neusa P; Freitas, Suely P

    2017-08-30

    Espresso capsule consumption and spent coffee ground (SCG) generation have increased, and the present study was undertaken to evaluate the volatile profile (VP), the antioxidant activity (AA) and the sun protection factor (SPF) of the Crude ethanolic extract obtained from the SCG in capsules. The extract yield was superior to the ether yield because a higher unsaponifiable matter (U.M.) amount was recovered by ethanol. The obtained VP (70 compounds) was typical of roasted coffee oil. Furthermore, chemometric analysis using principal components (PCA) discriminated the extracts and grouped the replicates for each sample, which showed the repeatability of the extraction process. The AA ranged from 18.4 to 23.6 (mg extract mg DPPH(-1)) and the SPF from 2.27 to 2.76. The combination of the coffee VP, AA and SPF gave the espresso SCG's crude ethanolicextract, desirable properties that can be used in cosmetic and food industries. Copyright © 2017. Published by Elsevier Ltd.

  3. Applications for Energy Recovering Free Electron Lasers

    Energy Technology Data Exchange (ETDEWEB)

    George Neil

    2007-08-01

    The availability of high-power, high-brilliance sources of tunable photons from energy-recovered Free Electron Lasers is opening up whole new fields of application of accelerators in industry. This talk will review some of the ideas that are already being put into production, and some of the newer ideas that are still under development.

  4. Some Representation Theorems for Recovering Contraction Relations

    Institute of Scientific and Technical Information of China (English)

    Ping Hou

    2005-01-01

    One of the important topics in the study of contraction inference relations is to establish the representation theorems for them. Various methods have been employed for giving representation of a broad class of contraction operations.However, there was not any canonical approach to dealing with the representation results for the contraction relations in the literature. Recently, in order to obtain the representation result for recovering contraction inference relations satisfying the condition weak conjunctive inclusion (wci), a notion of an image structure associated with the canonical epistemic state has been introduced. Based on the image structure, this paper establishes three representation results for recovering contraction inference relations which satisfy the conditions CL, CR1 and DR* respectively by the standard epistemic AGM states. A unique technique and uniform proofs to represent these contraction relations are adopted, which could overcome the core objection in previous description of contraction relations. The paper shows as well that the image structure and canonical epistemic states can be used not only to get the representation result for wci-recovering contraction relation, but also to provide semantic characterizations for a wide range of recovering contraction relations.

  5. Leaching process for recovering valuable metals from the LiNi1/3Co1/3Mn1/3O2 cathode of lithium-ion batteries.

    Science.gov (United States)

    He, Li-Po; Sun, Shu-Ying; Song, Xing-Fu; Yu, Jian-Guo

    2017-06-01

    In view of the importance of environmental protection and resource recovery, recycling of spent lithium-ion batteries (LIBs) and electrode scraps generated during manufacturing processes is quite necessary. An environmentally sound leaching process for the recovery of Li, Ni, Co, and Mn from spent LiNi1/3Co1/3Mn1/3O2-based LIBs and cathode scraps was investigated in this study. Eh-pH diagrams were used to determine suitable leaching conditions. Operating variables affecting the leaching efficiencies for Li, Ni, Co, and Mn from LiNi1/3Co1/3Mn1/3O2, such as the H2SO4 concentration, temperature, H2O2 concentration, stirring speed, and pulp density, were investigated to determine the most efficient conditions for leaching. The leaching efficiencies for Li, Ni, Co, and Mn reached 99.7% under the optimized conditions of 1M H2SO4, 1vol% H2O2, 400rpm stirring speed, 40g/L pulp density, and 60min leaching time at 40°C. The leaching kinetics of LiNi1/3Co1/3Mn1/3O2 were found to be significantly faster than those of LiCoO2. Based on the variation in the weight fraction of the metal in the residue, the "cubic rate law" was revised as follows: θ(1-f)(1/3)=(1-kt/r0ρ), which could characterize the leaching kinetics optimally. The activation energies were determined to be 64.98, 65.16, 66.12, and 66.04kJ/mol for Li, Ni, Co, and Mn, respectively, indicating that the leaching process was controlled by the rate of surface chemical reactions. Finally, a simple process was proposed for the recovery of valuable metals from spent LiNi1/3Co1/3Mn1/3O2-based LIBs and cathode scraps. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. PARAMETER ESTIMATION FOR A DISCRETELY OBSERVED STOCHASTIC VOLATILITY MODEL WITH JUMPS IN THE VOLATILITY

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In this paper a stochastic volatility model is considered. That is, a log price process Y whichis given in terms of a volatility process V is studied. The latter is defined such that the logprice possesses some of the properties empirically observed by Barndorff-Nielsen & Jiang[6]. Inthe model there are two sets of unknown parameters, one set corresponding to the marginaldistribution of V and one to autocorrelation of V. Based on discrete time observations ofthe log price the authors discuss how to estimate the parameters appearing in the marginaldistribution and find the asymptotic properties.

  7. Improved Predictions of Carbon Tetrachloride Contaminant Flow and Transport: Implementation of Kinetic Volatilization and Multicomponent NAPL Behavior

    Energy Technology Data Exchange (ETDEWEB)

    Oostrom, Martinus; Zhang, Z. F.; Freedman, Vicky L.; Tartakovsky, Guzel D.

    2008-09-29

    Carbon tetrachloride (CT) was discharged to waste sites that are included in the 200-PW-1 Operable Unit in Hanford 200 West Area. Fluor Hanford, Inc. is conducting a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) remedial investigation/feasibility study (RI/FS) for the 200-PW-1 Operable Unit. The RI/FS process and remedial investigations for the 200-PW-1, 200 PW-3, and 200-PW-6 Operable Units are described in the Plutonium/Organic-Rich Process Condensate/Process Waste Groups Operable Unit RI/FS Work Plan. As part of this overall effort, Pacific Northwest National Laboratory (PNNL) was contracted to improve the STOMP simulator (White and Oostrom, 2006) by incorporating kinetic volatilization of nonaqueous phase liquids (NAPL) and multicomponent flow and transport. This work supports the U.S. Department of Energy's (DOE's) efforts to characterize the nature and distribution of CT in the 200 West Area and subsequently select an appropriate final remedy. Previous numerical simulation results with the STOMP simulator have overestimated the effect of soil vapor extraction (SVE) on subsurface CT, showing rapid removal of considerably more CT than has actually been recovered so far. These previous multiphase simulations modeled CT mass transfer between phases based on equilibrium partitioning. Equilibrium volatilization can overestimate volatilization because mass transfer limitations present in the field are not considered. Previous simulations were also conducted by modeling the NAPL as a single component, CT. In reality, however, the NAPL mixture disposed of at the Hanford site contained several non-volatile and nearly insoluble organic components, resulting in time-variant fluid properties as the CT component volatilized or dissolved over time. Simulation of CT removal from a DNAPL mixture using single-component DNAPL properties typically leads to an overestimation of CT removal. Other possible reasons for the discrepancy

  8. Methods for recovering precious metals from industrial waste

    Science.gov (United States)

    Canda, L.; Heput, T.; Ardelean, E.

    2016-02-01

    The accelerated rate of industrialization increases the demand for precious metals, while high quality natural resources are diminished quantitatively, with significant operating costs. Precious metals recovery can be successfully made from waste, considered to be secondary sources of raw material. In recent years, concerns and interest of researchers for more increasing efficient methods to recover these metals, taking into account the more severe environmental protection legislation. Precious metals are used in a wide range of applications, both in electronic and communications equipment, spacecraft and jet aircraft engines and for mobile phones or catalytic converters. The most commonly recovered precious metals are: gold from jewellery and electronics, silver from X- ray films and photographic emulsions, industrial applications (catalysts, batteries, glass/mirrors), jewellery; platinum group metals from catalytic converters, catalysts for the refining of crude oil, industrial catalysts, nitric acid manufacturing plant, the carbon-based catalyst, e-waste. An important aspect is the economic viability of recycling processes related to complex waste flows. Hydrometallurgical and pyrometallurgical routes are the most important ways of processing electrical and electronic equipment waste. The necessity of recovering precious metals has opened new opportunities for future research.

  9. Multifractal Models, Intertrade Durations and Return Volatility

    OpenAIRE

    Segnon, Mawuli Kouami

    2015-01-01

    This thesis covers the application of multifractal processes in modeling financial time series. It aims to demonstrate the capacity and the robustness of the multifractal processes to better model return volatility and ultra high frequency financial data than both the generalized autoregressive conditional heteroscedasticity (GARCH)-type and autoregressive conditional duration (ACD) models currently used in research and practice. The thesis is comprised of four main parts that ...

  10. Recovering from conflict in romantic relationships: a developmental perspective.

    Science.gov (United States)

    Salvatore, Jessica E; Kuo, Sally I-Chun; Steele, Ryan D; Simpson, Jeffry A; Collins, W Andrew

    2011-03-01

    This study adopted a developmental perspective on recovery from conflict in romantic relationships. Participants were 73 young adults (target participants), studied since birth, and their romantic partners. A novel observational coding scheme was used to evaluate each participant's degree of conflict recovery, operationalized as the extent to which the participant disengaged from conflict during a 4-min "cool-down" task immediately following a 10-min conflict discussion. Conflict recovery was systematically associated with developmental and dyadic processes. Targets who were rated as securely attached more times in infancy recovered from conflict better, as did their romantic partners. Concurrently, having a romantic partner who displayed better recovery predicted more positive relationship emotions and greater relationship satisfaction. Prospectively, target participants' early attachment security and their partners' degree of conflict recovery interacted to predict relationship stability 2 years later, such that having a partner who recovered from conflict better buffered targets with insecure histories.

  11. Recovering lost 21 cm radial modes via cosmic tidal reconstruction

    CERN Document Server

    Zhu, Hong-Ming; Yu, Yu; Chen, Xuelei

    2016-01-01

    21 cm intensity mapping has emerged as a promising technique to map the large-scale structure of the Universe, at redshifts $z$ from 1 to 10. Unfortunately, many of the key cross correlations with photo-$z$ galaxies and the CMB have been thought to be impossible due to foreground contamination for radial modes with small wavenumbers. These modes are usually subtracted in the foreground subtraction process. We recover the lost 21 cm radial modes via cosmic tidal reconstruction and find more than 60\\% cross-correlation signal at $\\ell\\lesssim100$ and even more on larger scales can be recovered from null. The tidal reconstruction method opens up a new set of possibilities to probe our Universe and is extremely valuable not only for 21 cm surveys but also for CMB and photometric redshift observations.

  12. Recovering indium with sulfating roasting from copper-smelting ash

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A technology for recovering indium from Jinchuan copper-smelting ash was developed. Indium in the ash was first enriched to the leaching-slag in leaching process, and then recovered by sulfating roasting. The method included mixing the leaching-slag with sulfuric acid, making them into particles, roasting the mixture, and then leaching the calcine with hot water. Above 90% of indium in calcine could be dissolved into the leaching solution. The optimized conditions were determined as follows: the mass ratio of sulfuric acid to leaching slag was 0.1, the roasting time was about 1 to 1.5 h in the temperature range of 200-250 ℃, and the calcine was leached for 1 h with 5:1 of liquid/solid ratio at 60℃. Over 99% of indium in leaching solution was finally enriched by Zn substitution or sulfide precipitation.

  13. Plant volatiles in polluted atmospheres: stress responses and signal degradation

    National Research Council Canada - National Science Library

    BLANDE, JAMES D; HOLOPAINEN, JARMO K; NIINEMETS, ÜLO

    2014-01-01

    .... Volatiles induced by herbivore feeding are among the best studied plant responses to stress and may constitute an informative message to the surrounding community and further function in plant defence processes...

  14. Volatility smile as relativistic effect

    Science.gov (United States)

    Kakushadze, Zura

    2017-06-01

    We give an explicit formula for the probability distribution based on a relativistic extension of Brownian motion. The distribution (1) is properly normalized and (2) obeys the tower law (semigroup property), so we can construct martingales and self-financing hedging strategies and price claims (options). This model is a 1-constant-parameter extension of the Black-Scholes-Merton model. The new parameter is the analog of the speed of light in Special Relativity. However, in the financial context there is no ;speed limit; and the new parameter has the meaning of a characteristic diffusion speed at which relativistic effects become important and lead to a much softer asymptotic behavior, i.e., fat tails, giving rise to volatility smiles. We argue that a nonlocal stochastic description of such (Lévy) processes is inadequate and discuss a local description from physics. The presentation is intended to be pedagogical.

  15. Recovering of images degraded by atmosphere

    Science.gov (United States)

    Lin, Guang; Feng, Huajun; Xu, Zhihai; Li, Qi; Chen, Yueting

    2017-08-01

    Remote sensing images are seriously degraded by multiple scattering and bad weather. Through the analysis of the radiative transfer procedure in atmosphere, an image atmospheric degradation model considering the influence of atmospheric absorption multiple scattering and non-uniform distribution is proposed in this paper. Based on the proposed model, a novel recovering method is presented to eliminate atmospheric degradation. Mean-shift image segmentation and block-wise deconvolution are used to reduce time cost, retaining a good result. The recovering results indicate that the proposed method can significantly remove atmospheric degradation and effectively improve contrast compared with other removal methods. The results also illustrate that our method is suitable for various degraded remote sensing, including images with large field of view (FOV), images taken in side-glance situations, image degraded by atmospheric non-uniform distribution and images with various forms of clouds.

  16. GC-MS analysis of volatile oils from fresh and processed Typhonii Rhizoma%禹白附生品和制品挥发油成分及稳定性

    Institute of Scientific and Technical Information of China (English)

    张婷婷; 陈晓珍; 罗应刚

    2011-01-01

    目的:比较禹白附生品和制品挥发油成分与含量的差别,并考察禹白附挥发性成分的稳定性.方法:采用水蒸气蒸馏法分别提取禹白附生品和制品挥发油,立即通过GC-MS技术分离并鉴定其中的化学成分;同时在不同条件进行放置,一定时间后再运用GC-MS技术分离并鉴定其中的化学成分;最后运用主成分分析法统计分析所得数据.结果:从禹白附生品中共分离鉴定出43个化合物,从制品中则共分离鉴定出34个化合物;其中共有成分15个.生品和制品中的主要成分、含量差异明显;不同条件放置后生品制品的挥发油成分发生明显变化.结论:禹白附生品和制品的挥发油主要成分不同,且含量差异显著;禹白附生品和制品的挥发油成分不稳定,挥发油成分在不同条件发生明显变化.%Typhonii Rhizoma is a toxic traditional Chinese medicine. Its toxic components remained unclear. To compare chemical composition of volatile oils from fresh and processed Typhonii Rhizoma qualitatively, volatile oils were obtained by stream distillation and analyzed by GC-MS. The data obtained from GC-MS were processed by principal component analysis. From the essential oils of fresh and processed Typhonii Rhizoma, 43 compounds and 34 compounds were identified respectively. The chemical composition and content in the two oils was different. In the two essential oils 15 identical components were detected. The chemical components and their contents in the essential oils are changing with the storage.

  17. Recovering hydrocarbons with surfactants from lignin

    Energy Technology Data Exchange (ETDEWEB)

    Naae, D.G.; Whittington, L.E.; Ledoux, W.A.; Debons, F.E.

    1988-11-29

    This patent describes a method of recovering hydrocarbons from an underground hydrocarbon formation penetrated by at least one injection well and at least one production well, which comprises: injecting into the formation through an injection well a surfactant slug comprising about 0.1% to about 10% by weight of surfactants produced from lignin, the surfactants produced by placing lignin in contact with water, converting the lignin into low molecular weight lignin phenols by reducing the lignin in the presence of a reducing agent of carbon monoxide or hydrogen creating a reduction reaction mixture comprising oil soluble lignin phenols, the reduction occurring at a temperature greater than about 200/sup 0/C and a pressure greater than about 100 psi, recovering the oil soluble lignin phenols from the reduction mixture, and converting the lignin phenols into lignin surfactants by a reaction selected from the group consisting of alkoxylation, sulfonation, sulfation, aklylation, sulfomethylation, and alkoxysulfation; injecting into the formation through the injection well a drive fluid to push the surfactant slug towards a production well; and recovering hydrocarbons at the production well.

  18. Recovering chaotic properties from small data.

    Science.gov (United States)

    Shao, Chenxi; Fang, Fang; Liu, Qingqing; Wang, Tingting; Wang, Binghong; Yin, Peifeng

    2014-12-01

    Physical properties are obviously essential to study a chaotic system that generates discrete-time signals, but recovering chaotic properties of a signal source from small data is a very troublesome work. Existing chaotic models are weak in dealing with such case in that most of them need big data to exploit those properties. In this paper, geometric theory is considered to solve this problem. We build a smooth trajectory from series to implicitly exhibit the chaotic properties with series-nonuniform rational B-spline (S-NURBS) modeling method, which is presented by our team to model slow-changing chaotic time series. As for the part of validation, we reveal how well our model recovers the properties from both the statistical and the chaotic aspects to confirm the effectiveness of the model. Finally a practical chaotic model is built up to recover the chaotic properties contained in the Musa standard dataset, which is used in analyzing software reliability, thereby further proves the high credibility of this model in practical time series. The effectiveness of the S-NURBS modeling leads us to believe that it is really a feasible and worthy research area to study chaotic systems from geometric perspective. For this reason, we reckon that we have opened up a new horizon for chaotic system research.

  19. Medical errors recovered by critical care nurses.

    Science.gov (United States)

    Dykes, Patricia C; Rothschild, Jeffrey M; Hurley, Ann C

    2010-05-01

    : The frequency and types of medical errors are well documented, but less is known about potential errors that were intercepted by nurses. We studied the type, frequency, and potential harm of recovered medical errors reported by critical care registered nurses (CCRNs) during the previous year. : Nurses are known to protect patients from harm. Several studies on medical errors found that there would have been more medical errors reaching the patient had not potential errors been caught earlier by nurses. : The Recovered Medical Error Inventory, a 25-item empirically derived and internally consistent (alpha =.90) list of medical errors, was posted on the Internet. Participants were recruited via e-mail and healthcare-related listservs using a nonprobability snowball sampling technique. Investigators e-mailed contacts working in hospitals or who managed healthcare-related listservs and asked the contacts to pass the link on to others with contacts in acute care settings. : During 1 year, 345 CCRNs reported that they recovered 18,578 medical errors, of which they rated 4,183 as potentially lethal. : Surveillance, clinical judgment, and interventions by CCRNs to identify, interrupt, and correct medical errors protected seriously ill patients from harm.

  20. Option Pricing using Realized Volatility

    DEFF Research Database (Denmark)

    Stentoft, Lars Peter

    In the present paper we suggest to model Realized Volatility, an estimate of daily volatility based on high frequency data, as an Inverse Gaussian distributed variable with time varying mean, and we examine the joint properties of Realized Volatility and asset returns. We derive the appropriate...... benchmark model estimated on return data alone. Hence the paper provides evidence on the value of using high frequency data for option pricing purposes....

  1. Option Pricing using Realized Volatility

    DEFF Research Database (Denmark)

    Stentoft, Lars Peter

    In the present paper we suggest to model Realized Volatility, an estimate of daily volatility based on high frequency data, as an Inverse Gaussian distributed variable with time varying mean, and we examine the joint properties of Realized Volatility and asset returns. We derive the appropriate d...... benchmark model estimated on return data alone. Hence the paper provides evidence on the value of using high frequency data for option pricing purposes....

  2. 发酵鸭肉肠加工工艺优化及挥发性风味物质检测%Optimal Processing and Volatile Flavor Compounds of Fermented Duck Sausage

    Institute of Scientific and Technical Information of China (English)

    石江涛; 王武; 邓诗诗; 魏玲

    2015-01-01

    以鸭腿为原料,选择嗜酸乳杆菌(L. plantarum)和戊糖片球菌(P. pentosaces)为发酵菌种,以感官评分为评价指标,采用单因素结合响应面试验方法优化发酵鸭肉肠的加工工艺,并采用固相微萃取和气质联用技术检测发酵鸭肉肠中挥发性风味物质的组成。结果表明:发酵鸭肉肠较佳的加工工艺条件为:发酵剂添加量106 CFU/g、发酵时间54 h、发酵温度27℃,此工艺下制作的发酵鸭肉肠具有较好的感官品质。从发酵鸭肉肠中检测出37种挥发性成分,包括醛类、醇类、烃类、酸类、酯类以及含氮类化合物等。%The process optimization using combination of single factor method and response surface methodology (RSM) for the production of fermented duck sausage from duck leg meat using a 1:1 mixture ofL. plantarum andP. pentosaces as starter culture was conducted in this study. The response was sensory evaluation score. Volatile compounds in fermented sausage were determined by solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). Results indicated that the optimal processing parameters of fermented duck sausage were 106 CFU/g starter culture, 54 h of fermentation time, and 27℃ of fermentation temperature. Totally 37 volatile lfavor compounds including aldehydes, alcohols, hydrocarbons, acids, esters and nitrogenous compounds were identiifed in fermented duck sausage.

  3. Volatile signals during pregnancy.

    Science.gov (United States)

    Vaglio, Stefano

    2010-01-01

    Scents play a key role in mediating reproductive interactions in many vertebrates including mammals. Nowadays, several studies indicate that humans seem to use remarkably olfactory communication and are even able to produce and perceive pheromones. Furthermore, over the past several years, it became increasingly clear that pheromone-like chemical signals probably play a role in offspring identification and mother recognition. Recently developed technical procedures (solid-phase microextraction and dynamic headspace extraction) now allow investigators to characterize volatile compounds with high reliability. We analyzed the volatile compounds in sweat patch samples collected from the para-axillary and nipple-areola regions of women during pregnancy and after childbirth. We hypothesized that, at the time of birth and during the first weeks of life, the distinctive olfactory pattern of the para-axillary area is probably useful to newborn babies for recognizing and distinguishing their own mother, whereas the characteristic pattern of the nipple-areola region is probably useful as a guide to nourishment.

  4. Molecular plant volatile communication.

    Science.gov (United States)

    Holopainen, Jarmo K; Blande, James D

    2012-01-01

    Plants produce a wide array of volatile organic compounds (VOCs) which have multiple functions as internal plant hormones (e.g., ethylene, methyl jasmonate and methyl salicylate), in communication with conspecific and heterospecific plants and in communication with organisms of second (herbivores and pollinators) and third (enemies of herbivores) trophic levels. Species specific VOCs normally repel polyphagous herbivores and those specialised on other plant species, but may attract specialist herbivores and their natural enemies, which use VOCs as host location cues. Attraction of predators and parasitoids by VOCs is considered an evolved indirect defence, whereby plants are able to indirectly reduce biotic stress caused by damaging herbivores. In this chapter we review these interactions where VOCs are known to play a crucial role. We then discuss the importance of volatile communication in self and nonself detection. VOCs are suggested to appear in soil ecosystems where distinction of own roots from neighbours roots is essential to optimise root growth, but limited evidence of above-ground plant self-recognition is available.

  5. Supercritical fluid extraction of volatile and non-volatile compounds from Schinus molle L.

    Directory of Open Access Journals (Sweden)

    M. S. T. Barroso

    2011-06-01

    Full Text Available Schinus molle L., also known as pepper tree, has been reported to have antimicrobial, antifungal, anti-inflammatory, antispasmodic, antipyretic, antitumoural and cicatrizing properties. This work studies supercritical fluid extraction (SFE to obtain volatile and non-volatile compounds from the aerial parts of Schinus molle L. and the influence of the process on the composition of the extracts. Experiments were performed in a pilot-scale extractor with a capacity of 1 L at pressures of 9, 10, 12, 15 and 20 MPa at 323.15 K. The volatile compounds were obtained by CO2 supercritical extraction with moderate pressure (9 MPa, whereas the non-volatile compounds were extracted at higher pressure (12 to 20 MPa. The analysis of the essential oil was carried out by GC-MS and the main compounds identified were sabinene, limonene, D-germacrene, bicyclogermacrene, and spathulenol. For the non-volatile extracts, the total phenolic content was determined by the Folin-Ciocalteau method. Moreover, one of the goals of this study was to compare the experimental data with the simulated yields predicted by a mathematical model based on mass transfer. The model used requires three adjustable parameters to predict the experimental extraction yield curves.

  6. A Consistent Pricing Model for Index Options and Volatility Derivatives

    DEFF Research Database (Denmark)

    Kokholm, Thomas

    We propose a flexible modeling framework for the joint dynamics of an index and a set of forward variance swap rates written on this index. Our model reproduces various empirically observed properties of variance swap dynamics and enables volatility derivatives and options on the underlying index...... to be priced consistently, while allowing for jumps in volatility and returns. An affine specification using Lévy processes as building blocks leads to analytically tractable pricing formulas for volatility derivatives, such as VIX options, as well as efficient numerical methods for pricing of European options...

  7. A Consistent Pricing Model for Index Options and Volatility Derivatives

    DEFF Research Database (Denmark)

    Cont, Rama; Kokholm, Thomas

    2013-01-01

    We propose a flexible modeling framework for the joint dynamics of an index and a set of forward variance swap rates written on this index. Our model reproduces various empirically observed properties of variance swap dynamics and enables volatility derivatives and options on the underlying index...... to be priced consistently, while allowing for jumps in volatility and returns. An affine specification using Lévy processes as building blocks leads to analytically tractable pricing formulas for volatility derivatives, such as VIX options, as well as efficient numerical methods for pricing of European options...

  8. A Consistent Pricing Model for Index Options and Volatility Derivatives

    DEFF Research Database (Denmark)

    Kokholm, Thomas

    We propose a flexible modeling framework for the joint dynamics of an index and a set of forward variance swap rates written on this index. Our model reproduces various empirically observed properties of variance swap dynamics and enables volatility derivatives and options on the underlying index...... to be priced consistently, while allowing for jumps in volatility and returns. An affine specification using Lévy processes as building blocks leads to analytically tractable pricing formulas for volatility derivatives, such as VIX options, as well as efficient numerical methods for pricing of European options...

  9. Bias-reduced estimation of long memory stochastic volatility

    DEFF Research Database (Denmark)

    Frederiksen, Per; Nielsen, Morten Ørregaard

    We propose to use a variant of the local polynomial Whittle estimator to estimate the memory parameter in volatility for long memory stochastic volatility models with potential nonstation- arity in the volatility process. We show that the estimator is asymptotically normal and capable of obtaining...... bias reduction as well as a rate of convergence arbitrarily close to the parametric rate, n1=2. A Monte Carlo study is conducted to support the theoretical results, and an analysis of daily exchange rates demonstrates the empirical usefulness of the estimators....

  10. FY 1999 development of a technology to recycle fabric products. Development of a technology to recover 'waste selvages' generated from weaving process and recycle them as fabric products; 1999 nendo sen'i seihin recycle gijutsu kaihatsu seika hokokusho. Seishoku no sai ni hasseisuru 'sutemimi' wo sairiyo shita orimono seihin gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    The development was made of technology to recover 'waste selvages' generated from the weaving process and recycle them as weaving yarn for bath/toiletry products such as bath mats and toilet mats. The FY 1999 results were summarized. Based on the results of the study made in the previous year, research was conducted using a rapier loom made by Saurer Co. to study the effect of change in selvage fabric on the tangling condition of waste yarn. As a result, it was confirmed that 'waste selvage standard' and 'tangling yarn threading chart' were the most suitable. As to the development of technique for winding 'waste selvages,' safety, operability and efficiency were confirmed of the exclusive winding device which moves associated with the waste selvage roller on the yarn supply side. As to the development of technique for sizing, twisting and heat-processing of 'waste selvages,' favorable results were obtained in the test on the sizing of 'waste selvage' in the dyeing process and the heating processing technique using fused yarn. Good results were also obtained in the test using an exclusive double twister on the twisting condition, strength and uniformity of 'waste selvages.' Also in the development of the winding machine corresponding to coarse yarn and the weaving technique corresponding to coarse yarn, the results obtained were favorable. (NEDO)

  11. Recovering an obstacle using integral equations

    KAUST Repository

    Rundell, William

    2009-05-01

    We consider the inverse problem of recovering the shape, location and surface properties of an object where the surrounding medium is both conductive and homogeneous and we measure Cauchy data on an accessible part of the exterior boundary. It is assumed that the physical situation is modelled by harmonic functions and the boundary condition on the obstacle is one of Dirichlet type. The purpose of this paper is to answer some of the questions raised in a recent paper that introduced a nonlinear integral equation approach for the solution of this type of problem.

  12. Rota hidrometalúrgica de recuperação de molibdênio, cobalto, níquel e alumínio de catalisadores gastos de hidrotratamento em meio ácido Hydrometallurgical route to recover molybdenum, nickel, cobalt and aluminum from spent hydrotreating catalysts in acid medium

    OpenAIRE

    Ivam Macedo Valverde Júnior; Jéssica Frontino Paulino; Julio Carlos Afonso

    2008-01-01

    This work describes a hydrometallurgical route for processing spent commercial catalysts (CoMo and NiMo/Al2O3). Samples were preoxidized (500 ºC, 5 h) in order to eliminate coke and other volatile species present. The calcined solid was dissolved in concentrated H2SO4 and water (1:1 vol/vol) at 90 ºC; the insoluble matter was separated from the solution. Molybdenum was recovered by solvent extraction using tertiary amines at pH around 1.8. Cobalt (or nickel) was separated by addition of aqueo...

  13. Consistent ranking of volatility models

    DEFF Research Database (Denmark)

    Hansen, Peter Reinhard; Lunde, Asger

    2006-01-01

    We show that the empirical ranking of volatility models can be inconsistent for the true ranking if the evaluation is based on a proxy for the population measure of volatility. For example, the substitution of a squared return for the conditional variance in the evaluation of ARCH-type models can...

  14. Political institutions and economic volatility

    NARCIS (Netherlands)

    Klomp, Jeroen; de Haan, Jakob

    2009-01-01

    We examine the effect of political 'institutions' on economic growth volatility, using data from more than 100 countries over the period 1960 to 2005, taking into account various control variables as suggested in previous studies. Our indicator of volatility is the relative standard deviation of the

  15. Volatile and Isotopic Imprints of Ancient Mars

    Science.gov (United States)

    Mahaffy, Paul R.; Conrad, Pamela G.

    2015-01-01

    The science investigations enabled by Curiosity rover's instruments focus on identifying and exploring the habitability of the Martian environment. Measurements of noble gases, organic and inorganic compounds, and the isotopes of light elements permit the study of the physical and chemical processes that have transformed Mars throughout its history. Samples of the atmosphere, volatiles released from soils, and rocks from the floor of Gale Crater have provided a wealth of new data and a window into conditions on ancient Mars.

  16. A new method of recovering polyhydroxyalkanoate from Azotobacter

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    After polyhydroxyalkanoate (PHA) fermentation for 42-48 h by the Azotobacter chroococcum G-3, the PHA content reached more than 75% of the dry weight. Biomass was isolated from culture by centrifugation and pretreated with freezing to release PHA pellet, then was treated with 10 g/L sodium dodecyl sulfate (SDS) for 15 min to effectively solubilize lipid and protein. Subsequently, it was further purified by digesting with 30% sodium hypochlorite (NaClO) for 3 min to remove peptidoglycan and non-PHA biomass. Finally, 98% PHA was obtained by diluting and rinsing with water, and the PHA recovered was suitable for processing.

  17. Emerging non-volatile memories

    CERN Document Server

    Hong, Seungbum; Wouters, Dirk

    2014-01-01

    This book is an introduction to the fundamentals of emerging non-volatile memories and provides an overview of future trends in the field. Readers will find coverage of seven important memory technologies, including Ferroelectric Random Access Memory (FeRAM), Ferromagnetic RAM (FMRAM), Multiferroic RAM (MFRAM), Phase-Change Memories (PCM), Oxide-based Resistive RAM (RRAM), Probe Storage, and Polymer Memories. Chapters are structured to reflect diffusions and clashes between different topics. Emerging Non-Volatile Memories is an ideal book for graduate students, faculty, and professionals working in the area of non-volatile memory. This book also: Covers key memory technologies, including Ferroelectric Random Access Memory (FeRAM), Ferromagnetic RAM (FMRAM), and Multiferroic RAM (MFRAM), among others. Provides an overview of non-volatile memory fundamentals. Broadens readers' understanding of future trends in non-volatile memories.

  18. An Intelligent Analysis Model for Multisource Volatile Memory

    Directory of Open Access Journals (Sweden)

    Xiaolu Zhang

    2013-09-01

    Full Text Available For the rapidly development of network and distributed computing environment, it make researchers harder to do analysis examines only from one or few pieces of data source in persistent data-oriented approaches, so as the volatile memory analysis either. Therefore, mass data automatically analysis and action modeling needs to be considered for reporting entire network attack process. To model multiple volatile data sources situation can help understand and describe both thinking process of investigator and possible action step for attacker. This paper presents a Game model for multisource volatile data and applies it to main memory images analysis with the definition of space-time feature for volatile element information. Abstract modeling allows the lessons gleaned in performing intelligent analysis, evidence filing and automating presentation. Finally, a test demo based on the model is also present to illustrate the whole procedure

  19. Five years post whiplash injury: Symptoms and psychological factors in recovered versus non-recovered

    Directory of Open Access Journals (Sweden)

    Stålnacke Britt-Marie

    2010-07-01

    Full Text Available Abstract Background Few studies have focused on the differences between persons who are recovered after whiplash injury and those who suffer from persistent disability. The primary aim of this study was therefore to examine differences in symptoms, psychological factors and life satisfaction between subjects classified as recovered and those with persistent disability five years after whiplash injury based on the Neck Disability Index (NDI. Methods A set of questionnaires was answered by 158 persons (75 men, 83 women to assess disability (NDI, pain intensity (VAS, whiplash-related symptoms (Rivermead Post-Concussion Symptoms Questionnaire, RPQ, post-traumatic stress (Impact of Event Scale, IES, depression (Beck's depression inventory, BDI and life satisfaction (LiSat-11. The participants were divided into three groups based on the results of the NDI: recovered (34.8%, mild disability (37.3% and moderate/severe disability (27.3%. Results The moderate/severe group reported significantly higher VAS, BDI and IES scores and lower level of physical health and psychological health compared to the mild and the recovered groups. Less significant differences were reported between the mild and the recovered groups. Conclusions The group with the highest disability score reported most health problems with pain, symptoms, depression, post-traumatic stress and decreased life satisfaction. These findings indicate that classifying these subjects into subgroups based on disability levels makes it possible to optimize the management and treatment after whiplash injury.

  20. Preparation of volatile fatty acid (VFA) calcium salts by anaerobic digestion of glucose.

    Science.gov (United States)

    Li, Xiaofen; Swan, Janis E; Nair, Giridhar R; Langdon, Alan G

    2015-01-01

    Many potentially useful intermediates such as hydrogen and volatile fatty acids (VFAs) are formed during the complex anaerobic digestion processes that produce methane from biomass. This study recovers VFAs from an anaerobic digester by a combination of gas stripping and absorption with calcium carbonate slurry. Glucose was used as the model substrate because it is readily available, inexpensive, and easily digested. Sludge from a meatworks anaerobic digester produced methane and carbon dioxide (and sometimes a small amount of hydrogen) when batch-fed with glucose. Conditioning the neutral anaerobic sludge to an acidic pH (below 4.8) was achieved using repeated 1 g L(-1) doses of glucose. After conditioning, mainly VFAs and hydrogen were produced. The intermediate VFAs could be stripped using headspace gas. In subsequent fed-batch digestion/stripping cycles, the pH decreased when glucose was added and then increased when the VFA was gas stripped. The predominant acids formed at low pH values were lactic, butyric, and acetic acids. Lactic acid was converted to VFAs during stripping. The VFA calcium salts recovered were 80% butyrate and 20% acetate with minor quantities of propionate and valerate.

  1. Governmentally amplified output volatility

    Science.gov (United States)

    Funashima, Yoshito

    2016-11-01

    Predominant government behavior is decomposed by frequency into several periodic components: updating cycles of infrastructure, Kuznets cycles, fiscal policy over business cycles, and election cycles. Little is known, however, about the theoretical impact of such cyclical behavior in public finance on output fluctuations. Based on a standard neoclassical growth model, this study intends to examine the frequency at which public investment cycles are relevant to output fluctuations. We find an inverted U-shaped relationship between output volatility and length of cycle in public investment. This implies that periodic behavior in public investment at a certain frequency range can cause aggravated output resonance. Moreover, we present an empirical analysis to test the theoretical implication, using the U.S. data in the period from 1968 to 2015. The empirical results suggest that such resonance phenomena change from low to high frequency.

  2. When will the Antarctic Ozone Hole Recover?

    Science.gov (United States)

    Newman, Paul A.; Nash, Eric R.; Kawa, S. Randolph; Montzka, Steve

    2006-01-01

    The Antarctic ozone hole develops each year and culminates by early Spring. Antarctic ozone values have been monitored since 1979 using satellite observations from the .TOMS instrument. The severity of the hole has been assessed from TOMS using the minimum total ozone value from the October monthly mean (depth of the hole) and by calculating the average size during the September-October period. Ozone is mainly destroyed by halogen catalytic cycles, and these losses are modulated by temperature variations in the collar of the polar lower stratospheric vortex. In this presentation, we show the relationships of halogens and temperature to, both the size and depth of the hole. Because atmospheric halogen levels are responding to international agreements that limit or phase out production, the amount of halogens in the stratosphere should decrease over the next few decades. Using projections of halogen levels combined with age-of-air estimates, we find that the ozone hole is recovering at an extremely slow rate and that large ozone holes will regularly recur over the next 2 decades. The ozone hole will begin to show first signs of recovery in about 2023, and the hole will fully recover to pre-1980 levels in approximately 2070. This 2070 recovery is 20 years later than recent projections.

  3. Process sampling module coupled with purge and trap-GC-FID for in situ auto-monitoring of volatile organic compounds in wastewater.

    Science.gov (United States)

    Liu, Hsin-Wang; Liu, Yung-Tsun; Wu, Bei-Zen; Nian, Hung-Chi; Chen, Hsing-Jung; Chiu, Kong-Hwa; Lo, Jiunn-Guang

    2009-12-15

    An automatic sampling device, i.e., process sampling module (PSM), connected with a purge and trap-GC-FID system has been developed for real-time monitoring of VOCs in wastewater. The system was designed to simultaneously monitor 17 compounds, including one polar compound, i.e., acetone, and 16 non-polar compounds. The trapping tube is packed with two adsorbents, Carbopack B and Carbosieve III, to trap target compounds. For the purpose of in situ monitoring, the flush valve of the sampling tube is composed of two two-way valves and a time controller to prevent absorption interference of the residue. The optimal conditions for the analytical system include a 12 min purge time at a temperature of 60 degrees C, and 4 min of desorption time with a desorption temperature of 260 degrees C. Good chromatograms have been obtained with the analytical system even if a cryogenic device and de-misting were not used. The relative standards deviation (RSD) of the system is between 2% and 13.4%, and accuracies between 0.3 and 23.5% have been achieved. The detection limits of the method range from 0.32 to 2.39 ppb. In this system, the four parts, i.e., PSM, P&T, GC, and FID, were simple, reliable and rugged. Also, the interface of these four parts was simple and dependable.

  4. Intensification of volatile organic compounds mass transfer in a compact scrubber using the O3/H2O2 advanced oxidation process: kinetic study and hydroxyl radical tracking.

    Science.gov (United States)

    Biard, Pierre-François; Couvert, Annabelle; Renner, Christophe; Levasseur, Jean-Pierre

    2011-11-01

    This study assesses the potential of ozonation and advanced oxidation process O(3)/H(2)O(2) to enhance the dimethyldisulfide (DMDS) mass transfer in a compact chemical scrubber developed for air treatment applications. Theoretical calculations, through Hatta number and enhancement factor evaluations for two parallel irreversible reactions, were compared to experimental data and enabled the description of the mass transfer mechanisms. These calculations required the determination of the kinetic constant of the DMDS oxidation by molecular ozone ( [Formula: see text] ) and the measurement of the hydroxyl radical concentration within the scrubber. The competitive kinetic method using the 1,2-dihydroxybenzene (resorcinol) enabled to determine a value of the kinetic constant [Formula: see text] of 1.1×10(6)M(-1)s(-1) at 293K. Then, experiments using para-chlorobenzoic acid in solution allowed measuring the average hydroxyl concentration in the scrubber between the inlet and the outlet depending on the chemical conditions (pH and inlet O(3) and H(2)O(2) concentrations). High hydroxyl radical concentrations (10(-8)M) and ratio of the HO°-to-O(3) exposure (R(ct)≈10(-4)) were put in evidence.

  5. Compressive Structured Light for Recovering Inhomogeneous Participating Media.

    Science.gov (United States)

    Gu, Jinwei; Nayar, Shree K; Grinspun, Eitan; Belhumeur, Peter N; Ramamoorthi, Ravi

    2013-03-01

    We propose a new method named compressive structured light for recovering inhomogeneous participating media. Whereas conventional structured light methods emit coded light patterns onto the surface of an opaque object to establish correspondence for triangulation, compressive structured light projects patterns into a volume of participating medium to produce images which are integral measurements of the volume density along the line of sight. For a typical participating medium encountered in the real world, the integral nature of the acquired images enables the use of compressive sensing techniques that can recover the entire volume density from only a few measurements. This makes the acquisition process more efficient and enables reconstruction of dynamic volumetric phenomena. Moreover, our method requires the projection of multiplexed coded illumination, which has the added advantage of increasing the signal-to-noise ratio of the acquisition. Finally, we propose an iterative algorithm to correct for the attenuation of the participating medium during the reconstruction process. We show the effectiveness of our method with simulations as well as experiments on the volumetric recovery of multiple translucent layers, 3D point clouds etched in glass, and the dynamic process of milk drops dissolving in water.

  6. Volatility Exposure for Strategic Asset Allocation

    OpenAIRE

    Briere, Marie; Burgues, Alexandre; Signori, Ombretta

    2010-01-01

    The authors examine the advantages of incorporating strategic exposure to equity volatility into the investment opportunity set of a long-term equity investor. They consider two standard volatility investments: implied volatility and volatility risk premium strategies. An analytical framework, which offers pragmatic solutions for long-term investors who seek exposure to volatility, is used to calibrate and assess the risk-return profiles of portfolios. The benefit of volatility exposure for a...

  7. Reduced Heart Rate Volatility

    Science.gov (United States)

    Grogan, Eric L.; Morris, John A.; Norris, Patrick R.; France, Daniel J.; Ozdas, Asli; Stiles, Renée A.; Harris, Paul A.; Dawant, Benoit M.; Speroff, Theodore

    2004-01-01

    Objective: To determine if using dense data capture to measure heart rate volatility (standard deviation) measured in 5-minute intervals predicts death. Background: Fundamental approaches to assessing vital signs in the critically ill have changed little since the early 1900s. Our prior work in this area has demonstrated the utility of densely sampled data and, in particular, heart rate volatility over the entire patient stay, for predicting death and prolonged ventilation. Methods: Approximately 120 million heart rate data points were prospectively collected and archived from 1316 trauma ICU patients over 30 months. Data were sampled every 1 to 4 seconds, stored in a relational database, linked to outcome data, and de-identified. HR standard deviation was continuously computed over 5-minute intervals (CVRD, cardiac volatility–related dysfunction). Logistic regression models incorporating age and injury severity score were developed on a test set of patients (N = 923), and prospectively analyzed in a distinct validation set (N = 393) for the first 24 hours of ICU data. Results: Distribution of CVRD varied by survival in the test set. Prospective evaluation of the model in the validation set gave an area in the receiver operating curve of 0.81 with a sensitivity and specificity of 70.1 and 80.0, respectively. CVRD predict death as early as 24 hours in the validation set. Conclusions: CVRD identifies a subgroup of patients with a high probability of dying. Death is predicted within first 24 hours of stay. We hypothesize CVRD is a surrogate for autonomic nervous system dysfunction. PMID:15319726

  8. Evolution of Volatile Compounds during the Distillation of Cognac Spirit.

    Science.gov (United States)

    Awad, Pierre; Athès, Violaine; Decloux, Martine Esteban; Ferrari, Gérald; Snakkers, Guillaume; Raguenaud, Patrick; Giampaoli, Pierre

    2017-09-06

    Cognac wine spirit has a complex composition in volatile compounds which contributes to its organoleptic profile. This work focused on the batch distillation process and, in particular, on volatile compounds specifically produced by chemical reactions during the distillation of Cognac wine spirit, traditionally conducted in two steps with charentais pot stills. The aim of this study was to characterize these volatile compounds formed during distillation. Sampling has been performed on the distillates and inside the boiler during a typical Cognac distillation. The analysis of these samples allowed us to perform a mass balance and to point out several types of volatile compounds whose quantities strongly increased during the distillation process. These compounds were distinguished by their chemical family. It has been found that the first distillation step was decisive for the formation of volatile compounds. Moreover, 2 esters, 3 aldehydes, 12 norisoprenoids, and 3 terpenes were shown to be generated during the process. These results suggest that some volatile compounds found in Cognac spirit are formed during distillation due to chemical reactions induced by high temperature. These findings give important indications to professional distillers in order to enhance the product's quality.

  9. Thermodynamics of Volatile Species in the Silicon-Oxygen-Hydrogen System Studied

    Science.gov (United States)

    Jacobson, Nathan S.; Opila, Elizabeth J.; Copland, Evan H.; Myers, Dwight

    2005-01-01

    The volatilization of silica (SiO2) to silicon hydroxides and oxyhydroxides because of reaction with water vapor is important in a variety of high-temperature corrosion processes. For example, the lifetimes of silicon carbide (SiC) and silicon nitride (Si3N4) - based components in combustion environments are limited by silica volatility. To understand and model this process, it is essential to have accurate thermodynamic data for the formation of volatile silicon hydroxides and oxyhydroxides.

  10. Recovering vitrified carnation (Dianthus caryophyllus L.) shoots using Bacto-Peptone and its subfractions.

    Science.gov (United States)

    Sato, S; Hagimori, M; Iwai, S

    1993-05-01

    Vitrified shoots regenerated from carnation petals (Dianthus caryophyllus L. cv. Scania) were recovered by culturing them in a medium containing 3.0 g/l Bacto-Peptone. Wax structures not found on vitrified shoots developed on the abaxial surface of leaves of recovered shoots and on those of normal leaves. Recovered shoots were rooted and successfully acclimatized while vitrified shoots could not survive the acclimatization process. The Bacto-Peptone solution was fractionated and the efficiency of each fraction for the recovery of vitrification was examined. Only basic, non high molecular fractions whose molecular weight was less than 10,000 were effective.

  11. Hygroscopic behavior of partially volatilized coastal marine aerosols using the volatilization and humidification tandem differential mobility analyzer technique

    Science.gov (United States)

    Johnson, G. R.; Ristovski, Z. D.; D'Anna, B.; Morawska, L.

    2005-10-01

    Coastal marine nucleation, Aitken, and accumulation mode aerosol particles with back trajectories indicative of marine origin were examined using a volatilization and humidification tandem differential mobility analyzer (VHTDMA) to reveal the volatilization temperatures of the various component species. The diameter hygroscopic growth factors of the residue particles were continually examined throughout the volatilization process. In each of the three modes the dominant particle type appeared to be composed of the same four physicochemically distinct species though in different ratios. These species exhibited volatility and hygroscopic behavior consistent with combinations of a volatile organic species, sulfuric acid, ammonium sulfate or bisulfate, iodine oxide, and an insoluble nonvolatile residue. The Aitken and accumulation mode aerosols contain large fractions of the insoluble, volatile, organic-like material, and the volatilization of this species results in a distinct increase in the water volume uptake of the particles. Of the four distinct species, only the sulfuric acid-like species constituted an increasing volume fraction with decreasing particle size. This finding indicates that nucleation mode particles constitute an acidic seed and as such would undergo acid-catalyzed secondary organic aerosol growth at a faster rate. The lack of a nonvolatile hygroscopic residue consistent with sea salt in these particles implies that the aerosolization of seawater is not the dominant production mechanism for these submicrometer coastal marine aerosols.

  12. Candidate Low-Temperature Glass Waste Forms for Technetium-99 Recovered from Hanford Effluent Management Facility Evaporator Concentrate

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Mei [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tang, Ming [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rim, Jung Ho [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chamberlin, Rebecca M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-07-24

    Alternative treatment and disposition options may exist for technetium-99 (99Tc) in secondary liquid waste from the Hanford Direct-Feed Low-Activity Waste (DFLAW) process. One approach includes development of an alternate glass waste form that is suitable for on-site disposition of technetium, including salts and other species recovered by ion exchange or precipitation from the EMF evaporator concentrate. By recovering the Tc content from the stream, and not recycling the treated concentrate, the DFLAW process can potentially be operated in a more efficient manner that lowers the cost to the Department of Energy. This report provides a survey of candidate glass formulations and glass-making processes that can potentially incorporate technetium at temperatures <700 °C to avoid volatilization. Three candidate technetium feed streams are considered: (1) dilute sodium pertechnetate loaded on a non-elutable ion exchange resin; (2) dilute sodium-bearing aqueous eluent from ion exchange recovery of pertechnetate, or (3) technetium(IV) oxide precipitate containing Sn and Cr solids in an aqueous slurry. From the technical literature, promising candidate glasses are identified based on their processing temperatures and chemical durability data. The suitability and technical risk of three low-temperature glass processing routes (vitrification, encapsulation by sintering into a glass composite material, and sol-gel chemical condensation) for the three waste streams was assessed, based on available low-temperature glass data. For a subset of candidate glasses, their long-term thermodynamic behavior with exposure to water and oxygen was modeled using Geochemist’s Workbench, with and without addition of reducing stannous ion. For further evaluation and development, encapsulation of precipitated TcO2/Sn/Cr in a glass composite material based on lead-free sealing glasses is recommended as a high priority. Vitrification of pertechnetate in aqueous anion exchange eluent solution

  13. Diagnostics For Recirculating And Energy Recovered Linacs

    Energy Technology Data Exchange (ETDEWEB)

    Geoffrey A. Krafft; Jean-Claude Denard

    2002-12-18

    In this paper, the electron beam diagnostics developed for recirculating electron accelerators will be reviewed. The main novelties in dealing with such accelerators are: to have sufficient information and control possibilities for the longitudinal phase space, to have means to accurately set the recirculation path length, and to have a means to distinguish the beam passes on measurements of position in the linac proper. The solutions to these problems obtained at Jefferson Laboratory and elsewhere will be discussed. In addition, more standard instrumentation (profiling and emittance measurements) will be reviewed in the context of recirculating linacs. Finally, and looking forward, electron beam diagnostics for applications to high current energy recovered linacs will be discussed.

  14. Volatile cycling and the thermal evolution of planetary mantle

    Science.gov (United States)

    Sandu, Constantin

    The thermal histories of terrestrial planets are investigated using two parameterized mantle convection models for either Earth like planets and planets with no active plate tectonics. Using parameterized models of mantle convection, we performed computer simulations of planetary cooling and volatile cycling. The models estimate the amount of volatile in mantle reservoir, and calculate the outgassing and regassing rates. A linear model of volatile concentration-dependent is assumed for the activation energy of the solid-state creep in the mantle. The kinematic viscosity of the mantle is thus dynamically affected by the activation energy through a variable concentration in volatile. Mantle temperature and heat flux is calculated using a model derived from classic thermal boundary layer theory of a single layered mantle with temperature dependent viscosity. The rate of volatile exchanged between mantle and surface is calculated by balancing the amount of volatiles degassed in the atmosphere by volcanic and spreading related processes and the amount of volatiles recycled back in the mantle by the subduction process. In the cases that lack plate tectonics, the degassing efficiency is dramatically reduced and the regassing process is absent. The degassing effect is dependent on average spreading rate of tectonic plates and on the amount of volatile in the melt extract in the transition zone between mantle and upper boundary laver. The regassing effect is dependent on the subduction rate and on the amount of volatile present on a hydrated layer on top of the subducting slab. The degassing and regassing parameters are all related to the intensity of the convection in the mantle and to the surface temperature of the planet, and they are regulated by the amount of volatiles in reservoir. Comparative study with the previous models display significant differences and improve the versatility of the model. The optimum efficiency factors found are in the range of 0.01--0.06 for

  15. Volatile compounds of commercial Milano salami.

    Science.gov (United States)

    Meynier, A; Novelli, E; Chizzolini, R; Zanardi, E; Gandemer, G

    1999-02-01

    The relationship between extracted volatiles of Milano salami, one of the main dry-cured sausages produced in Italy, and their olfactory properties was studied. Volatile compounds were extracted by a purge-and-trap method, quantified using a flame ionisation detector and identified by mass spectrometry. Olfactory analysis was performed by sniffing the gas chromatographic effluent. Nearly 80 compounds were identified and quantified: most came from spices (60.5%), 18.9% from lipid oxidation, 11.8% from amino acid catabolism and 4.9% from fermentation processes. Panellists detected 19 odours by sniffing. These odours were associated with spices, lipid oxidation or fermentation and were in agreement with the contributions of each reaction to the overall aroma of the product.

  16. Recent developments in volatility modeling and applications

    Directory of Open Access Journals (Sweden)

    A. Thavaneswaran

    2006-01-01

    Full Text Available In financial modeling, it has been constantly pointed out that volatility clustering and conditional nonnormality induced leptokurtosis observed in high frequency data. Financial time series data are not adequately modeled by normal distribution, and empirical evidence on the non-normality assumption is well documented in the financial literature (details are illustrated by Engle (1982 and Bollerslev (1986. An ARMA representation has been used by Thavaneswaran et al., in 2005, to derive the kurtosis of the various class of GARCH models such as power GARCH, non-Gaussian GARCH, nonstationary and random coefficient GARCH. Several empirical studies have shown that mixture distributions are more likely to capture heteroskedasticity observed in high frequency data than normal distribution. In this paper, some results on moment properties are generalized to stationary ARMA process with GARCH errors. Application to volatility forecasts and option pricing are also discussed in some detail.

  17. Rota hidrometalúrgica de recuperação de molibdênio, cobalto, níquel e alumínio de catalisadores gastos de hidrotratamento em meio ácido Hydrometallurgical route to recover molybdenum, nickel, cobalt and aluminum from spent hydrotreating catalysts in acid medium

    Directory of Open Access Journals (Sweden)

    Ivam Macedo Valverde Júnior

    2008-01-01

    Full Text Available This work describes a hydrometallurgical route for processing spent commercial catalysts (CoMo and NiMo/Al2O3. Samples were preoxidized (500 ºC, 5 h in order to eliminate coke and other volatile species present. The calcined solid was dissolved in concentrated H2SO4 and water (1:1 vol/vol at 90 ºC; the insoluble matter was separated from the solution. Molybdenum was recovered by solvent extraction using tertiary amines at pH around 1.8. Cobalt (or nickel was separated by addition of aqueous ammonium oxalate at the above pH. Phosphorus was removed by passing the liquid through a strong anion exchange column. Aluminum was recovered by neutralizing the solution with NaOH. The route presented in this work generates less final aqueous wastes because it is not necessary to use alkaline medium during the metal recovery steps.

  18. Approximation methods of European option pricing in multiscale stochastic volatility model

    Science.gov (United States)

    Ni, Ying; Canhanga, Betuel; Malyarenko, Anatoliy; Silvestrov, Sergei

    2017-01-01

    In the classical Black-Scholes model for financial option pricing, the asset price follows a geometric Brownian motion with constant volatility. Empirical findings such as volatility smile/skew, fat-tailed asset return distributions have suggested that the constant volatility assumption might not be realistic. A general stochastic volatility model, e.g. Heston model, GARCH model and SABR volatility model, in which the variance/volatility itself follows typically a mean-reverting stochastic process, has shown to be superior in terms of capturing the empirical facts. However in order to capture more features of the volatility smile a two-factor, of double Heston type, stochastic volatility model is more useful as shown in Christoffersen, Heston and Jacobs [12]. We consider one modified form of such two-factor volatility models in which the volatility has multiscale mean-reversion rates. Our model contains two mean-reverting volatility processes with a fast and a slow reverting rate respectively. We consider the European option pricing problem under one type of the multiscale stochastic volatility model where the two volatility processes act as independent factors in the asset price process. The novelty in this paper is an approximating analytical solution using asymptotic expansion method which extends the authors earlier research in Canhanga et al. [5, 6]. In addition we propose a numerical approximating solution using Monte-Carlo simulation. For completeness and for comparison we also implement the semi-analytical solution by Chiarella and Ziveyi [11] using method of characteristics, Fourier and bivariate Laplace transforms.

  19. Water Vapor-Mediated Volatilization of High-Temperature Materials

    Science.gov (United States)

    Meschter, Peter J.; Opila, Elizabeth J.; Jacobson, Nathan S.

    2013-07-01

    Volatilization in water vapor-containing atmospheres is an important and often unexpected mechanism of degradation of high-temperature materials during processing and in service. Thermodynamic properties data sets for key (oxy)hydroxide vapor product species that are responsible for material transport and damage are often uncertain or unavailable. Estimation, quantum chemistry calculation, and measurement methods for thermodynamic properties of these species are reviewed, and data judged to be reliable are tabulated and referenced. Applications of water vapor-mediated volatilization include component and coating recession in turbine engines, oxidation/volatilization of ferritic steels in steam boilers, chromium poisoning in solid-oxide fuel cells, vanadium transport in hot corrosion and degradation of hydrocracking catalysts, Na loss from Na β"-Al2O3 tubes, and environmental release of radioactive isotopes in a nuclear reactor accident or waste incineration. The significance of water vapor-mediated volatilization in these applications is described.

  20. Determining Energy Use Volatility for Commercial Mortgage Valuation

    Energy Technology Data Exchange (ETDEWEB)

    Mathew, Paul [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Pang, XiuFeng [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wang, Liping [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-06-01

    Commercial mortgage contracts currently do not fully account for the risks inherent in the level and volatility of energy use in commercial buildings. As a result, energy efficiency is not explicitly included in the valuation process for commercial mortgage underwriting. In particular, there is limited if any consideration of the volatility of energy use and price, which is critical to evaluate the impact of extreme events and default risk. Explicit inclusion of energy use and volatility in commercial mortgage underwriting can send a strong “price signal” that financially rewards and values energy efficiency in commercial properties. This report presents the results of a technical analysis of and a proposed protocol to assess energy use volatility for the purposes of commercial mortgage valuation.

  1. VOCs催化反应过程与反应机理研究现状%Research Status of Volatile Organic Compounds(VOCs)Catalytic Oxidation Process and Mechanism

    Institute of Scientific and Technical Information of China (English)

    岳琳

    2014-01-01

    Reviews the research status of volatile organic compounds catalytic oxidation process and mechanism,such as catalyst characterization,research methods of catalytic process,and different research systems. In-situ technology and X-ray absorption fine structure (XAFS) in catalyst characterization can preferably elucidate the catalytic process and mechanism. The research of catalytic oxidation process mainly include reaction kinetic models (the Power-rate Law, the Mars-van Krevelen Model, and the Langmuir-Hinshelwood), reaction monitoring technology (In-situ FTIR, In-situ NMR, transient technique, isotopic tracing) , quantum chemical calculation, et al. Generally, reaction kinetics is one of the most widely techniques for the mechanism research of catalytic oxidation. The reaction products can be directly detected,which adsorb more attention. The research of quantum chemical calculation is just used for proof.%论述了挥发性有机污染物(VOCs)催化反应过程机理研究的现状,包括催化剂的表征、催化过程研究方法以及不同的研究体系。催化剂表征使用原位技术以及X射线吸收精细结构(XAFS)方法可以更好地阐述催化剂在催化过程中的作用与机制。催化过程研究主要包括催化反应动力学模拟(Power-rate Law、Mars-van Krevelen Model、Langmuir-Hinshelwood),反应产物监测(原位红外技术、原位核磁技术、暂态技术、同位素示踪技术),量子化学计算等。其中,反应动力学是使用较为广泛的研究催化反应机制的技术之一。反应产物监测可以得到直观的认识,获得了广大学者的关注。量子化学计算只作为论证。

  2. 薄荷、肉桂中挥发油提取及β-环糊精包合工艺研究%Extraction of volatile oil from Herba Menthae and Cortex Cinnamomi and its inclusion process with β-cyclodextrin

    Institute of Scientific and Technical Information of China (English)

    卫强; 杜会兰; 胡娟; 杨春燕

    2011-01-01

    目的:研究七味养心健脾胶囊中薄荷、肉桂挥发油的提取及包合工艺条件和参数。方法:以吸水率、浸泡时间、加水量、提取时间等为考察指标,分别比较薄荷、肉桂挥发油提取条件,选择优化条件;以β-环糊精-油比例、包合温度、包合时间等因素进行正交试验,优选挥发油包合工艺条件。结果:薄荷、肉桂浸泡4 h,加水10倍,提取3 h,挥发油含量较高;最佳包合条件为:β-环糊精-油比例为5∶1,包合温度为60℃,包合时间2 h。用薄层鉴别和紫外鉴别,包合前后挥发油质量不变。结论:薄荷、肉桂包合工艺可改善挥发油挥发性,提高制剂质量。%Objective: To study the optimum extraction process of volatile oil from Herba Menthae and Cortex Cinnamomi,and their inclusion process with β-cyclodextri in Qiwei Yangxinjianpi capsule.Methods: Effects of water absorption,soak time,water volume and extracting time on extraction of volatile oil were investigated,and the inclusion process with β-CD were optimized by orthogonal design.Results: Optimal extracting condition was as follows: adding 10 times distilled water,soaking for 4 hours,distilling three hours;The optimum conditions of inclusive compound were the proportion of 1∶5(volatile oil to β-CD),2 hours of inclusion at 60 ℃.Thin-layer chromatography and ultraviolet scanning analysis showed that the quality of volatile oil was stable before and after inclusion.Conclusion: This inclusion process can improve the volatility of volatile oil and preparation property.

  3. Removal of volatile fatty acids and ammonia recovery from unstable anaerobic digesters with a microbial electrolysis cell.

    Science.gov (United States)

    Cerrillo, Míriam; Viñas, Marc; Bonmatí, August

    2016-11-01

    Continuous assays with a microbial electrolysis cell (MEC) fed with digested pig slurry were performed to evaluate its stability and robustness to malfunction periods of an anaerobic digestion (AD) reactor and its feasibility as a strategy to recover ammonia. When performing punctual pulses of volatile fatty acids (VFA) in the anode compartment of the MEC, simulating a malfunction of the AD process, an increase in the current density was produced (up to 14 times, reaching values of 3500mAm(-2)) as a result of the added chemical oxygen demand (COD), especially when acetate was used. Furthermore, ammonium diffusion from the anode to the cathode compartment was enhanced and the removal efficiency achieved up to 60% during daily basis VFA pulses. An AD-MEC combined system has proven to be a robust and stable configuration to obtain a high quality effluent, with a lower organic and ammonium content.

  4. On forecasting Exchange Rate Volatility.

    OpenAIRE

    Hafner, Christian

    2003-01-01

    In an efficient market, foreign exchange rates have to guarantee absence of triangular arbitrage. This note shows that the no-arbitrage condition can be exploited for forecasting the volatility of a single rate by using the information contained in the other rates. Linearly transforming the volatility forecasts of a bivariate model is shown to be more efficient than using a univariate model for the cross-rate.

  5. Process for simultaneously processing of used metal and/or metal scrap and scrap containing halogenated hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Dapper, G.; Kirchner, W.; Sloterdijk, W.; Verbraak, C.A.

    1982-03-02

    A process is presened for reducing environmental pollution resulting from disposal of waste containing halogenated hydrocarbons by simultaneous treatment with used metal and/or metal scrap at elevated temperatures. The halogenated hydrocarbons are pyrolyzed and the resulting hydrogen halide containing gas is brought into contact with the used metal and/or metal scrap at elevated temperatures so as to form metal halogenides that are volatile under the conditions applied. The volatile metal halogenides are largely separated from the gaseous mixture formed, and at least part of the remaining gaseous mixture and/or hydrocarbon residue is used as fuel to maintain the required temperature. The waste feed compositions and process conditions can be chosen to effect separation between various metals by selective halogenation and condensation, and substantially all of the hydrogen halide can be tied up and recovered as metal halogenides.

  6. High-Current Energy-Recovering Electron Linacs

    Energy Technology Data Exchange (ETDEWEB)

    Nikolitsa Merminga; David Douglas; Geoffrey Krafft

    2003-12-01

    The use of energy recovery provides a potentially powerful new paradigm for generation of the charged particle beams used in synchrotron radiation sources, high-energy electron cooling devices, electron-ion colliders, and other applications in photon science and nuclear and high-energy physics. Energy-recovering electron linear accelerators (called energy-recovering linacs, or ERLs) share many characteristics with ordinary linacs, as their six-dimensional beam phase space is largely determined by electron source properties. However, in common with classic storage rings, ERLs possess a high average-current-carrying capability enabled by the energy recovery process, and thus promise similar efficiencies. The authors discuss the concept of energy recovery and its technical challenges and describe the Jefferson Lab (JLab) Infrared Demonstration Free-Electron Laser (IR Demo FEL), originally driven by a 3548-MeV, 5-mA superconducting radiofrequency (srf) ERL, which provided the most substantial demonstration of energy recovery to date: a beam of 250 kW average power. They present an overview of envisioned ERL applications and a development path to achieving the required performance. They use experimental data obtained at the JLab IR Demo FEL and recent experimental results from CEBAF-ERL GeV-scale, comparatively low-current energy-recovery demonstration at JLab to evaluate the feasibility of the new applications of high-current ERLs, as well as ERLs' limitations and ultimate performance.

  7. Selenium Uptake and Volatilization by Marine Algae

    Science.gov (United States)

    Luxem, Katja E.; Vriens, Bas; Wagner, Bettina; Behra, Renata; Winkel, Lenny H. E.

    2015-04-01

    Selenium (Se) is an essential trace nutrient for humans. An estimated one half to one billion people worldwide suffer from Se deficiency, which is due to low concentrations and bioavailability of Se in soils where crops are grown. It has been hypothesized that more than half of the atmospheric Se deposition to soils is derived from the marine system, where microorganisms methylate and volatilize Se. Based on model results from the late 1980s, the atmospheric flux of these biogenic volatile Se compounds is around 9 Gt/year, with two thirds coming from the marine biosphere. Algae, fungi, and bacteria are known to methylate Se. Although algal Se uptake, metabolism, and methylation influence the speciation and bioavailability of Se in the oceans, these processes have not been quantified under environmentally relevant conditions and are likely to differ among organisms. Therefore, we are investigating the uptake and methylation of the two main inorganic Se species (selenate and selenite) by three globally relevant microalgae: Phaeocystis globosa, the coccolithophorid Emiliania huxleyi, and the diatom Thalassiosira oceanica. Selenium uptake and methylation were quantified in a batch experiment, where parallel gas-tight microcosms in a climate chamber were coupled to a gas-trapping system. For E. huxleyi, selenite uptake was strongly dependent on aqueous phosphate concentrations, which agrees with prior evidence that selenite uptake by phosphate transporters is a significant Se source for marine algae. Selenate uptake was much lower than selenite uptake. The most important volatile Se compounds produced were dimethyl selenide, dimethyl diselenide, and dimethyl selenyl sulfide. Production rates of volatile Se species were larger with increasing intracellular Se concentration and in the decline phase of the alga. Similar experiments are being carried out with P. globosa and T. oceanica. Our results indicate that marine algae are important for the global cycling of Se

  8. Exactly Recovering Low-Rank Matrix in Linear Time via $l_1$ Filter

    CERN Document Server

    Liu, Risheng; Su, Zhixun

    2011-01-01

    Recovering a low rank matrix from corrupted data, which is known as Robust PCA, has attracted considerable interests in recent years. This problem can be exactly solved by a combined nuclear norm and $l_1$ norm minimization. However, due to the computational burden of SVD inherent with the nuclear norm minimization, traditional methods suffer from high computational complexity, especially for large scale datasets. In this paper, inspired by digital filtering idea in image processing, we propose a novel algorithm, named $l_1$ Filter, for solving Robust PCA with linear cost. The $l_1$ Filter is defined by a seed, which is a exactly recovered small submatrix of the underlying low rank matrix. By solving some $l_1$ minimization problems in parallel, the full low rank matrix can be exactly recovered from corrupted observations with linear cost. Both theoretical analysis and experimental results exhibit that our method is an efficient way to exactly recovering low rank matrix in linear time.

  9. Volatile compounds in low-acid fermented sausage "espetec" and sliced cooked pork shoulder subjected to high pressure processing. A comparison of dynamic headspace and solid-phase microextraction.

    Science.gov (United States)

    Rivas-Cañedo, Ana; Juez-Ojeda, Cristina; Nuñez, Manuel; Fernández-García, Estrella

    2012-05-01

    Two extraction techniques, dynamic headspace extraction (DHE) and solid-phase microextraction (SPME), were compared to assess the effect of high-pressure treatment (400MPa, 10min, 12°C) on the volatile compounds of low-acid fermented sausage "espetec" and sliced cooked pork shoulder stored at 4°C. DHE was more efficient at extracting low-boiling compounds such as ethanal, 2,3-butanedione and alcohols, while SPME extracted more efficiently a higher number of chemical families, especially fatty acids. The effect of pressurisation on the volatile fraction of "espetec" was better categorized by DHE, whereas SPME was more appropriate for cooked pork shoulder. The volatile fraction of "espetec" changed slightly after pressurisation, mainly showing a decrease in the levels of lipid-derived compounds, like linear alkanes, aldehydes, or 1-alcohols in pressurised samples. The volatile profile of cooked pork shoulder underwent substantial changes during refrigerated storage, mainly due to microbial metabolism, most of these changes being limited by HPP.

  10. Volatility Forecasting: Downside Risk, Jumps and Leverage Effect

    Directory of Open Access Journals (Sweden)

    Francesco Audrino

    2016-02-01

    Full Text Available We provide empirical evidence of volatility forecasting in relation to asymmetries present in the dynamics of both return and volatility processes. Using recently-developed methodologies to detect jumps from high frequency price data, we estimate the size of positive and negative jumps and propose a methodology to estimate the size of jumps in the quadratic variation. The leverage effect is separated into continuous and discontinuous effects, and past volatility is separated into “good” and “bad”, as well as into continuous and discontinuous risks. Using a long history of the S & P500 price index, we find that the continuous leverage effect lasts about one week, while the discontinuous leverage effect disappears after one day. “Good” and “bad” continuous risks both characterize the volatility persistence, while “bad” jump risk is much more informative than “good” jump risk in forecasting future volatility. The volatility forecasting model proposed is able to capture many empirical stylized facts while still remaining parsimonious in terms of the number of parameters to be estimated.

  11. Asymmetry Effects in Chinese Stock Markets Volatility: A Generalized Additive Nonparametric Approach

    OpenAIRE

    Hou, Ai Jun

    2007-01-01

    The unique characteristics of the Chinese stock markets make it difficult to assume a particular distribution for innovations in returns and the specification form of the volatility process when modeling return volatility with the parametric GARCH family models. This paper therefore applies a generalized additive nonparametric smoothing technique to examine the volatility of the Chinese stock markets. The empirical results indicate that an asymmetric effect of negative news exists in the Chin...

  12. Trading Strategy with Stochastic Volatility in a Limit Order Book Market

    OpenAIRE

    Ching, Wai-Ki; Gu, Jia-Wen; Siu, Tak-Kuen; Yang, Qing-Qing

    2016-01-01

    In this paper, we employ the Heston stochastic volatility model to describe the stock's volatility and apply the model to derive and analyze the optimal trading strategies for dealers in a security market. We also extend our study to option market making for options written on stocks in the presence of stochastic volatility. Mathematically, the problem is formulated as a stochastic optimal control problem and the controlled state process is the dealer's mark-to-market wealth. Dealers in the s...

  13. Volatility Transmission of Overnight Rate along the Yield Curve in Pakistan

    OpenAIRE

    Mahmood, Asif

    2014-01-01

    This paper presented the empirical results of the volatility transmission of overnight rate along the yield curve in case of Pakistan. The results indicate that the volatility transmission of overnight repo rate is higher at the shorter end of the yield curve while lower at the longer end. These results are in line with both theoretical and empirical underpinning of the interest rates volatility transmission process found in other countries. Moreover, the results also suggest that the pass-th...

  14. Formation of volatile chemicals from thermal degradation of less volatile coffee components: quinic acid, caffeic acid, and chlorogenic acid.

    Science.gov (United States)

    Moon, Joon-Kwan; Shibamoto, Takayuki

    2010-05-12

    The less volatile constituents of coffee beans (quinic acid, caffeic acid, and chlorogenic acid) were roasted under a stream of nitrogen, air, or helium. The volatile degradation compounds formed were analyzed by gas chromatography and gas chromatography-mass spectrometry. Caffeic acid produced the greatest amount of total volatiles. Quinic acid and chlorogenic acid produced a greater number of volatiles under the nitrogen stream than under the air stream. These results suggest that the presence of oxygen does not play an important role in the formation of volatile compounds by the heat degradation of these chemicals. 2,5-Dimethylfuran formed in relatively large amounts (59.8-2231.0 microg/g) in the samples obtained from quinic acid and chlorogenic acid but was not found in the samples from caffeic acid. Furfuryl alcohol was found in the quinic acid (259.9 microg/g) and caffeic acid (174.4 microg/g) samples roasted under a nitrogen stream but not in the chlorogenic sample. The three acids used in the present study do not contain a nitrogen atom, yet nitrogen-containing heterocyclic compounds, pyridine, pyrrole, and pyrazines, were recovered. Phenol and its derivatives were identified in the largest quantities. The amounts of total phenols ranged from 60.6 microg/g (quinic acid under helium) to 89893.7 microg/g (caffeic acid under helium). It was proposed that phenol was formed mainly from quinic acid and that catechols were formed from caffeic acid. Formation of catechol from caffeic acid under anaerobic condition indicates that the reaction participating in catechol formation was not oxidative degradation.

  15. Re-connecting with a Recovering River through Imaginative Engagement

    Directory of Open Access Journals (Sweden)

    Clare Morgan

    2010-09-01

    Full Text Available Imaginative engagement as a mode of citizen participation—the use of arts-based methods to involve people actively in shared learning experiences—holds promise as a means to increase awareness and understanding, and to build capacity, for sustainable use and management of rivers. We conducted a series of creative writing workshops in a former industrial area of northern England that were focused on a "recovering" river. Participants in the workshops found the process a positive experience and reported changes in their knowledge, attitudes, and actions about the use and management of river environments locally and more generally. The "catchment consciousness" of members appeared to increase, and their raised levels of interest led them to invest time in researching the history and geography of the river. We conclude that the method has significant potential for complementing collaborative approaches to river planning and management.

  16. Technique for Recovering Pile-Up Events from Microcalorimeter Data

    Science.gov (United States)

    Wulf, D.; Jaeckel, F.; McCammon, D.; Morgan, K. M.

    2016-07-01

    We report here a technique for processing microcalorimeter data that offers improved live-time over conventional optimal filtering techniques without loss of spectral resolution. Separate filters optimized for pulse amplitude and pulse arrival time (constructed in the usual way from the averaged signal and noise spectral densities) are applied to the entire pixel data stream. Pulses in the resulting filtered streams are then simultaneously fit as the sum of scaled and shifted copies of an isolated filtered pulse template. Analysis using calibration data from the University of Wisconsin/Goddard Space Flight Center X-ray quantum calorimeter sounding rocket payload demonstrates the ability of this technique to recover pulses separated by as little as the rise-time of the detectors without observable spectral broadening.

  17. A Simple Test for Causality in Volatility

    Directory of Open Access Journals (Sweden)

    Chia-Lin Chang

    2017-03-01

    Full Text Available An early development in testing for causality (technically, Granger non-causality in the conditional variance (or volatility associated with financial returns was the portmanteau statistic for non-causality in the variance of Cheng and Ng (1996. A subsequent development was the Lagrange Multiplier (LM test of non-causality in the conditional variance by Hafner and Herwartz (2006, who provided simulation results to show that their LM test was more powerful than the portmanteau statistic for sample sizes of 1000 and 4000 observations. While the LM test for causality proposed by Hafner and Herwartz (2006 is an interesting and useful development, it is nonetheless arbitrary. In particular, the specification on which the LM test is based does not rely on an underlying stochastic process, so the alternative hypothesis is also arbitrary, which can affect the power of the test. The purpose of the paper is to derive a simple test for causality in volatility that provides regularity conditions arising from the underlying stochastic process, namely a random coefficient autoregressive process, and a test for which the (quasi- maximum likelihood estimates have valid asymptotic properties under the null hypothesis of non-causality. The simple test is intuitively appealing as it is based on an underlying stochastic process, is sympathetic to Granger’s (1969, 1988 notion of time series predictability, is easy to implement, and has a regularity condition that is not available in the LM test.

  18. Generation of saffron volatiles by thermal carotenoid degradation.

    Science.gov (United States)

    Carmona, Manuel; Zalacain, Amaya; Salinas, M Rosario; Alonso, Gonzalo L

    2006-09-06

    Generation of volatiles by thermal treatments has been studied in saffron spice for two reasons: (a) to determine volatile profile changes during simulated aging processes and (b) to study the volatile generation pathway. During the aging process, while the amounts of C10 compounds such as safranal and HTCC increase, the amounts of C9 compounds such as isophorone and 2,6,6-trimethylcyclohexane-1,4-dione decrease. A new compound tentatively identified as 4,5,6,7-tetrahydro-7,7-dimethyl-5-oxo-3H-isobenzofuranone seems to play a very important role in the aging process. The importance of this compound, structurally similar to dihydroactindiolide, was also confirmed when the saffron volatile fraction was analyzed via the degradation of the linear chain of crocetin and crocetin esters and is reported for the first time in this paper. Thermal degradation studies of zeaxanthin, crocetin, and trans and cis crocetin esters isomers allowed us to propose different mechanisms which explain saffron volatile generation depending on the crocetin ester isomer structure.

  19. The hydrogen concentration as parameter to identify natural attenuation processes of volatile chlorinated hydrocarbons in ground water; Die Wasserstoffkonzentration als Parameter zur Identifizierung des natuerlichen Abbaus von leichtfluechtigen Chlorkohlenwasserstoffen (LCKW) im Grundwasser

    Energy Technology Data Exchange (ETDEWEB)

    Alter, M.D.

    2006-06-15

    In this study, the hydrogen concentration as parameter to identify natural attenuation processes of volatile chlorinated hydrocarbons was investigated. The currently accepted and recommended bubble strip method for hydrogen sampling was optimized, and a storage method for hydrogen samples was developed. Furthermore batch experiments with a dechlorinating mixed culture and pure cultures were carried out to study H{sub 2}-concentrations of competing redox processes. The extraction of hydrogen from ground water was optimized by a reduced inlet diameter of the usually applied gas sampling bulbs, allowing a maximal turbulent ow and gas transfer. With a gas volume of 10 ml and flow rates of 50 to 140 ml/min, the course of extraction almost followed the theoretical course of equilibration. At flow rates > 100 ml/min a equilibrium of 98% was achieved within 20 min. Until recently it was generally accepted that hydrogen samples can be stored only for 2 hours and therefore have to be analyzed immediately in the eld. Here, it was shown that eld samples can be stored for 1-3 days until analysis. For the dechlorination of tetrachloroethene (PCE), a hydrogen threshold concentration of 1-2 nM was found with the dechlorinating mixed culture as well as with a pure culture of Sulfurospirillum multivorans in combination with another pure culture Methanosarcina mazei. No dechlorination was detectable below this concentration. With the dechlorinating mixed culture, this finding is valid for all successive dechlorination steps until ethene. The hydrogen threshold concentration for denitrification were below the detection limit of 0,2 nM with the dechlorinating mixed culture. A threshold concentration of 3,1-3,5 nM was found for sulphate reduction and a threshold of 7-9 nM H{sub 2} for hydrogenotrophic methanogenesis. This implies that the natural dechlorination at contaminated sites is preferred to competing processes like sulphate reduction and methanogenesis. The threshold

  20. Effects of minerals in ferric bauxite on sodium carbonate decomposition and volatilization

    Institute of Scientific and Technical Information of China (English)

    胡文韬; 王化军; 刘欣伟; 孙传尧

    2015-01-01

    Direct reduction is an emerging technology for ferric bauxite utilization. However, because of sodium volatilization, its sodium carbonate consumption is considerably higher than that in ordinary bauxite processing technology. TG-DSC and XRD were applied to detecting phase transformation and mass loss in direct reduction to reveal the mechanism on sodium volatilization. The results show that the most significant influence factor of ferric bauxite on sodium volatilization in direct reduction system is its iron content. Sodium volatilization is probably ascribed to the instability of amorphous substances structure. Amorphous substances are the intermediate-products of the reaction, and the volatilization rate of sodium increases with its generating rate. These amorphous substances are volatile, thus, more sodium is volatilized with its generation. A small amount of amorphous substances are generated in the reaction between Na2CO3and Al2O3; thus, only 3.15% of sodium is volatilized. Similarly, the volatilization rate is 1.87% in the reaction between Na2CO3and SiO2. However, the volatilization rate reaches 7.64% in the reaction between Na2CO3 and Fe2O3 because of the generation of a large amount of amorphous substances.

  1. RICE PRICE VOLATILITY IN EAST JAVA

    Directory of Open Access Journals (Sweden)

    Wati R.Y.E.

    2017-09-01

    Full Text Available The purpose of the research is analyzing the volatility and volatility spillover of monthly price of paddy at the level of farmers and consumers in 2010-2016. ARCH/GARCH used to analyze volatility and GARCH BEKK-model is used to analyze the volatility spillover. The results of the analysis show that price volatility at the farmer level is very high (extremely high volatility, price volatility at the consumer level is low (low volatility, and volatility spillover does not occur between the farmers and the consumers market. The need to guarantee an effective floor price as well as information disclosure related to the market commodity prices so that the pattern of prices transmission among interrelated markets can be symmetrical.

  2. The price of fixed income market volatility

    CERN Document Server

    Mele, Antonio

    2015-01-01

    Fixed income volatility and equity volatility evolve heterogeneously over time, co-moving disproportionately during periods of global imbalances and each reacting to events of different nature. While the methodology for options-based "model-free" pricing of equity volatility has been known for some time, little is known about analogous methodologies for pricing various fixed income volatilities. This book fills this gap and provides a unified evaluation framework of fixed income volatility while dealing with disparate markets such as interest-rate swaps, government bonds, time-deposits and credit. It develops model-free, forward looking indexes of fixed-income volatility that match different quoting conventions across various markets, and uncovers subtle yet important pitfalls arising from naïve superimpositions of the standard equity volatility methodology when pricing various fixed income volatilities. The ultimate goal of the authors´ efforts is to make interest rate volatility standardization a valuable...

  3. Kinetics of recovering germanium from lignite ash with chlorinating roasting methods

    Institute of Scientific and Technical Information of China (English)

    ZHU Guocai; WANG Jingyan; CHENG Zhuo; ZHAO Yuna

    2008-01-01

    A process of recovering Ge by chlorinating roasting was put forward. GeCl4 was separated and recovered from lignite ash because of its low boiling point. Kinetic analysis indicates that the chlorinating roasting process fits with the unreacted-core shrinking model and the reaction rate equation corresponds to 1-2a/3-(1-a)2/3 =kt. The apparent activation energy Ea is calculated to be 22.36 kJ·mol-1. The diffusion of product layer serves as the rate-controlling step in this process. When the roasting temperature is 250℃, the roasting time is 60 min, the concentration of hydrochloric acid is 10 mol/L, and the ratio of liquid to solid is 10 (mHCl/ash=10), and 90% Ge in lignite ash can be recovered.

  4. Stability and `volatility ` of element 104 oxychloride

    Energy Technology Data Exchange (ETDEWEB)

    Eichler, B.; Gaeggeler, H.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    The formation enthalpies {Delta}H{sup *} of solid and gaseous oxychlorides of element 104 from free atoms were estimated by extrapolation. Stability and volatility of these compounds are compared to those of the homologous and neighbouring elements in the periodic system. It can be supposed that in a gas adsorption chromatographic process with oxygen containing chlorinating carrier gas the transport with the carrier gas flow occurs in the chemical state 104Cl{sub 4}. Only in the absorbed state the compound 104OCl{sub 2} is formed. (author) 1 fig., 3 refs.

  5. Volatile Organic Compound emissions from soil: using Proton-Transfer-Reaction Time-of-Flight Mass Spectrometry (PTR-TOF-MS) for the real time observation of microbial processes

    Science.gov (United States)

    Veres, P. R.; Behrendt, T.; Klapthor, A.; Meixner, F. X.; Williams, J.

    2014-08-01

    In this study we report on the emissions of volatile organic compounds (VOC) and nitric oxide (NO) from two contrasting soils (equatorial rainforest and arid cotton field) analyzed in a laboratory based dynamic chamber system. The effect of soil moisture and soil temperature on VOC and NO emission was examined in laboratory incubation experiments by measuring as a pre-saturated soil dried out. Our results suggest that real time monitoring of VOC emissions from soil using a proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF-MS) instrument can be used to improve our understanding of the release mechanisms of trace gases (e.g. NO, N2O) that are involved in the nitrogen cycle. Moreover, we report on the release rate of various VOC species, many of which exhibit a temperature dependent response indicative of biological production, namely a temperature amplification factor (Q10) ∼ 2-3. Contrary to the conventional modeling of NO emissions from soils, that the release of NO from the overall community across the range of soil water content can be modeled as an optimum function, we suggest that VOC measurements indicate there exist multiple distinct contributing microbial guilds releasing NO. These microbial guilds could likely be individually identified with the observed VOC profiles. Using a cotton field soil sample from a Sache oasis (Taklimakan desert, Xinijang, P. R. China), we identify five VOC emission groups with varying degrees of NO co-emission. An equatorial rainforest soil (Suriname) was shown to emit a variety of VOC including acetaldehyde, acetone, DMS, formaldehyde, and isoprene that vary strongly and individually as a function of temperature and soil moisture content. PTR-TOF-MS with high time resolution, sensitivity, and molecular specificity is an ideal tool for the real time analysis of VOC and NO emitting processes in soil systems. These experiments can be used as a template for future experiments to more completely and specifically

  6. Observability of market daily volatility

    Science.gov (United States)

    Petroni, Filippo; Serva, Maurizio

    2016-02-01

    We study the price dynamics of 65 stocks from the Dow Jones Composite Average from 1973 to 2014. We show that it is possible to define a Daily Market Volatility σ(t) which is directly observable from data. This quantity is usually indirectly defined by r(t) = σ(t) ω(t) where the r(t) are the daily returns of the market index and the ω(t) are i.i.d. random variables with vanishing average and unitary variance. The relation r(t) = σ(t) ω(t) alone is unable to give an operative definition of the index volatility, which remains unobservable. On the contrary, we show that using the whole information available in the market, the index volatility can be operatively defined and detected.

  7. Consistent ranking of volatility models

    DEFF Research Database (Denmark)

    Hansen, Peter Reinhard; Lunde, Asger

    2006-01-01

    result in an inferior model being chosen as "best" with a probability that converges to one as the sample size increases. We document the practical relevance of this problem in an empirical application and by simulation experiments. Our results provide an additional argument for using the realized...... variance in out-of-sample evaluations rather than the squared return. We derive the theoretical results in a general framework that is not specific to the comparison of volatility models. Similar problems can arise in comparisons of forecasting models whenever the predicted variable is a latent variable.......We show that the empirical ranking of volatility models can be inconsistent for the true ranking if the evaluation is based on a proxy for the population measure of volatility. For example, the substitution of a squared return for the conditional variance in the evaluation of ARCH-type models can...

  8. Oil Volatility Risk and Expected Stock Returns

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Pan, Xuhui (Nick)

    After the financialization of commodity futures markets in 2004-05 oil volatility has become a strong predictor of returns and volatility of the overall stock market. Furthermore, stocks' exposure to oil volatility risk now drives the cross-section of expected returns. The difference in average...... return between the quintile of stocks with low exposure and high exposure to oil volatility is significant at 0.66% per month, and oil volatility risk carries a significant risk premium of -0.60% per month. In the post-financialization period, oil volatility risk is strongly related with various measures...

  9. Volatile compounds in samples of cork and also produced by selected fungi.

    Science.gov (United States)

    Barreto, M C; Vilas Boas, L; Carneiro, L C; San Romão, M V

    2011-06-22

    The production of volatile compounds by microbial communities of cork samples taken during the cork manufacturing process was investigated. The majority of volatiles were found in samples collected at two stages: resting after the first boiling and nontreated cork disks. Volatile profiles produced by microbiota in both stages are similar. The releasable volatile compounds and 2,4,6-trichloroanisole (TCA) produced in cork-based culture medium by five isolated fungal species in pure and mixed cultures were also analyzed by gas chromatography coupled with mass spectrometry (GC-MS).The results showed that 1-octen-3-ol and esters of fatty acids (medium chain length C8-C20) were the main volatile compounds produced by either pure fungal species or their mixture. Apparently, Penicillium glabrum is the main contributor to the overall volatile composition observed in the mixed culture. The production of releasable TCA on cork cannot be attributed to any of the assayed fungal isolates.

  10. Modeling the Implied Volatility Surface-: A Study for S&P 500 Index Option

    Directory of Open Access Journals (Sweden)

    Jin Zheng

    2013-02-01

    Full Text Available The aim of this study is to demonstrate a framework to model the implied volatilities of S&P 500 index options and estimate the implied volatilities of stock prices using stochastic processes. In this paper, three models are established to estimate whether the implied volatilities are constant during the whole life of options. We mainly concentrate on the Black-Scholes and Dumas’ option models and make the empirical comparisons. By observing the daily-recorded data of S&P 500 index, we study the volatility model and volatility surface. Results from numerical experiments show that the stochastic volatilities are determined by moneyness rather than constant. Our research is of vital importance, especially for forecasting stock market shocks and crises, as one of the applications.

  11. Volatilization of parathion and chlorothalonil from a potato crop simulated by the PEARL model.

    Science.gov (United States)

    Leistra, Minze; van den Berg, Frederik

    2007-04-01

    The volatilization of pesticides from crop canopies in the field should be modeled within the context of evaluating environmental exposure. A model concept based on diffusion through a laminar air-boundary layer was incorporated into the PEARL model (pesticide emission assessment at regional and local scales) and used to simulate volatilization of the pesticides parathion and chlorothalonil from a potato crop in a field experiment. Rate coefficients for the competing processes of plant penetration, wash off, and phototransformation in the canopy had to be derived from a diversity of literature data. Cumulative volatilization of the moderately volatile parathion (31% of the dosage in 7.6 days) could be simulated after calibrating two input data derived for the related compound parathion-methyl. The less volatile and more slowly transformed chlorothalonil showed 5% volatilization in 7.6 days, which could be explained by the simulation. Simulated behavior of the pesticides in the crop canopy roughly corresponded to published data.

  12. Volatilization of zinc and lead in direct recycling of stainless steel making dust

    Institute of Scientific and Technical Information of China (English)

    PENG Ji(彭及); PENG Bing(彭兵); YU Di(余笛); TANG Mo-tang(唐谟堂); J.Lobel; J.A.Kozinski

    2004-01-01

    The volatilization of zinc and lead from the stainless steel making dust pellets in the direct recycling procedure was conducted by using a thermo-gravimetric analyzer and a Tamman furnace in the nitrogen atmosphere respectively. The results show that the temperature has a significant effect on the volatilization rates of zinc and lead,and the carbon content in the pellets has no effect on the volatilization process. The volatilization of zinc is controlled by the chemical reaction between zinc oxide and carbon monoxide, while the volatilization of lead is controlled by the evaporation front liquid phase to the atmosphere. The volatilization of zinc and lead mainly happen at about 1 000 ℃according to non-isothermal experiment.

  13. Rhenium volatilization in waste glasses

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Kai; Pierce, David A. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Hrma, Pavel, E-mail: pavel.hrma@pnnl.gov [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Schweiger, Michael J. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Kruger, Albert A. [U.S. Department of Energy, Office of River Protection, Richland, WA 99352 (United States)

    2015-09-15

    Highlights: • Re did not volatilize from a HLW feed until 1000 °C. • Re began to volatilize from LAW feeds at ∼600 °C. • The vigorous foaming and generation of gases from salts enhanced Re evaporation in LAW feeds. • The HLW glass with less foaming and salts is a promising medium for Tc immobilization. - Abstract: We investigated volatilization of rhenium (Re), sulfur, cesium, and iodine during the course of conversion of high-level waste melter feed to glass and compared the results for Re volatilization with those in low-activity waste borosilicate glasses. Whereas Re did not volatilize from high-level waste feed heated at 5 K min{sup −1} until 1000 °C, it began to volatilize from low-activity waste borosilicate glass feeds at ∼600 °C, a temperature ∼200 °C below the onset temperature of evaporation from pure KReO{sub 4}. Below 800 °C, perrhenate evaporation in low-activity waste melter feeds was enhanced by vigorous foaming and generation of gases from molten salts as they reacted with the glass-forming constituents. At high temperatures, when the glass-forming phase was consolidated, perrhenates were transported to the top surface of glass melt in bubbles, typically together with sulfates and halides. Based on the results of this study (to be considered preliminary at this stage), the high-level waste glass with less foaming and salts appears a promising medium for technetium immobilization.

  14. Analyzing Malware Based on Volatile Memory

    Directory of Open Access Journals (Sweden)

    Liang Hu

    2013-11-01

    Full Text Available To explain the necessity of comprehensive and automatically analysis process for volatile memory, this paper summarized ordinarily analyzing methods and their common points especially for concerned data source. Then, a memory analysis framework Volatiltiy-2.2 and statistical output file size are recommended. In addition, to address the limitation of plug-ins classification in analyzing procedure, a user perspective classify is necessary and proposed. Furthermore, according to target data source differences on the base of result data set volume and employed relational method is introduced for comprehensive analysis guideline procedure. Finally, a test demo including DLLs loading order list analyzing is recommend, in which DLL load list is regard as different kind of characteristics typical data source with process and convert into process behavior fingerprint. The clustering for the fingerprint is employed string similar degree algorithm model in the demo, which has a wide range applications in traditional malware behavior analysis, and it is proposed that these methods also can be applied for volatile memory

  15. Investigating Long-Range Dependence in American Treasury Bills Variations and Volatilities during Stable and Unstable Periods

    Science.gov (United States)

    Lahmiri, Salim

    2016-05-01

    Detrended fluctuation analysis (DFA) is used to examine long-range dependence in variations and volatilities of American treasury bills (TB) during periods of low and high movements in TB rates. Volatility series are estimated by generalized autoregressive conditional heteroskedasticity (GARCH) model under Gaussian, Student, and the generalized error distribution (GED) assumptions. The DFA-based Hurst exponents from 3-month, 6-month, and 1-year TB data indicates that in general the dynamics of the TB variations process is characterized by persistence during stable time period (before 2008 international financial crisis) and anti-persistence during unstable time period (post-2008 international financial crisis). For volatility series, it is found that; for stable period; 3-month volatility process is more likely random, 6-month volatility process is anti-persistent, and 1-year volatility process is persistent. For unstable period, estimation results show that the generating process is persistent for all maturities and for all distributional assumptions.

  16. Leverage and Feedback Effects on Multifactor Wishart Stochastic Volatility for Option Pricing

    NARCIS (Netherlands)

    M. Asai (Manabu); M.J. McAleer (Michael)

    2013-01-01

    textabstractThe paper proposes a general asymmetric multifactor Wishart stochastic volatility (AMWSV) diffusion process which accommodates leverage, feedback effects and multifactor for the covariance process. The paper gives the closed-form solution for the conditional and unconditional Laplace

  17. DOES ENERGY CONSUMPTION VOLATILITY AFFECT REAL GDP VOLATILITY? AN EMPIRICAL ANALYSIS FOR THE UK

    Directory of Open Access Journals (Sweden)

    Abdul Rashid

    2013-10-01

    Full Text Available This paper empirically examines the relation between energy consumption volatility and unpredictable variations in real gross domestic product (GDP in the UK. Estimating the Markov switching ARCH model we find a significant regime switching in the behavior of both energy consumption and GDP volatility. The results from the Markov regime-switching model show that the variability of energy consumption has a significant role to play in determining the behavior of GDP volatilities. Moreover, the results suggest that the impacts of unpredictable variations in energy consumption on GDP volatility are asymmetric, depending on the intensity of volatility. In particular, we find that while there is no significant contemporaneous relationship between energy consumption volatility and GDP volatility in the first (low-volatility regime, GDP volatility is significantly positively related to the volatility of energy utilization in the second (high-volatility regime.

  18. Factors affecting the volatilization of volatile organic compounds from wastewater

    Directory of Open Access Journals (Sweden)

    Junya Intamanee

    2006-09-01

    Full Text Available This study aimed to understand the influence of the wind speed (U10cm, water depth (h and suspended solids (SS on mass transfer coefficient (KOLa of volatile organic compounds (VOCs volatilized from wastewater. The novelty of this work is not the method used to determine KOLa but rather the use of actual wastewater instead of pure water as previously reported. The influence of U10cm, h, and SS on KOLa was performed using a volatilization tank with the volume of 100-350 L. Methyl Ethyl Ketone (MEK was selected as a representative of VOCs investigated here in. The results revealed that the relationship between KOLa and the wind speeds falls into two regimes with a break at the wind speed of 2.4 m/s. At U10cm 2.4 m/s, KOLa increased more rapidly. The relationship between KOLa and U10cm was also linear but has a distinctly higher slope. For the KOLa dependency on water depth, the KOLa decreased significantly with increasing water depth up to a certain water depth after that the increase in water depth had small effect on KOLa. The suspended solids in wastewater also played an important role on KOLa. Increased SS resulted in a significant reduction of KOLa over the investigated range of SS. Finally, the comparison between KOLa obtained from wastewater and that of pure water revealed that KOLa from wastewater were much lower than that of pure water which was pronounced at high wind speed and at small water depth. This was due the presence of organic mass in wastewater which provided a barrier to mass transfer and reduced the degree of turbulence in the water body resulting in low volatilization rate and thus KOLa. From these results, the mass transfer model for predicting VOCs emission from wastewater should be developed based on the volatilization of VOCs from wastewater rather than that from pure water.

  19. Fluidized bed gasification of industrial solid recovered fuels.

    Science.gov (United States)

    Arena, Umberto; Di Gregorio, Fabrizio

    2016-04-01

    The study evaluates the technical feasibility of the fluidized bed gasification of three solid recovered fuels (SRFs), obtained as co-products of a recycling process. The SRFs were pelletized and fed to a pilot scale bubbling fluidized bed reactor, operated in gasification and co-gasification mode. The tests were carried out under conditions of thermal and chemical steady state, with a bed of olivine particles and at different values of equivalence ratio. The results provide a complete syngas characterization, in terms of its heating value and composition (including tars, particulates, and acid/basic pollutants) and of the chemical and physical characterization of bed material and entrained fines collected at the cyclone outlet. The feasibility of the fluidized bed gasification process of the different SRFs was evaluated with the support of a material and substance flow analysis, and a feedstock energy analysis. The results confirm the flexibility of fluidized bed reactor, which makes it one of the preferable technologies for the gasification of different kind of wastes, even in co-gasification mode. The fluidized bed gasification process of the tested SRFs appears technically feasible, yielding a syngas of valuable quality for energy applications in an appropriate plant configuration.

  20. The volatile compound BinBase mass spectral database

    Directory of Open Access Journals (Sweden)

    Barupal Dinesh K

    2011-08-01

    Full Text Available Abstract Background Volatile compounds comprise diverse chemical groups with wide-ranging sources and functions. These compounds originate from major pathways of secondary metabolism in many organisms and play essential roles in chemical ecology in both plant and animal kingdoms. In past decades, sampling methods and instrumentation for the analysis of complex volatile mixtures have improved; however, design and implementation of database tools to process and store the complex datasets have lagged behind. Description The volatile compound BinBase (vocBinBase is an automated peak annotation and database system developed for the analysis of GC-TOF-MS data derived from complex volatile mixtures. The vocBinBase DB is an extension of the previously reported metabolite BinBase software developed to track and identify derivatized metabolites. The BinBase algorithm uses deconvoluted spectra and peak metadata (retention index, unique ion, spectral similarity, peak signal-to-noise ratio, and peak purity from the Leco ChromaTOF software, and annotates peaks using a multi-tiered filtering system with stringent thresholds. The vocBinBase algorithm assigns the identity of compounds existing in the database. Volatile compound assignments are supported by the Adams mass spectral-retention index library, which contains over 2,000 plant-derived volatile compounds. Novel molecules that are not found within vocBinBase are automatically added using strict mass spectral and experimental criteria. Users obtain fully annotated data sheets with quantitative information for all volatile compounds for studies that may consist of thousands of chromatograms. The vocBinBase database may also be queried across different studies, comprising currently 1,537 unique mass spectra generated from 1.7 million deconvoluted mass spectra of 3,435 samples (18 species. Mass spectra with retention indices and volatile profiles are available as free download under the CC-BY agreement (http

  1. 27 CFR 24.130 - Change in volatile fruit-flavor concentrate operations.

    Science.gov (United States)

    2010-04-01

    ...-flavor concentrate operations. 24.130 Section 24.130 Alcohol, Tobacco Products and Firearms ALCOHOL AND... Subsequent to Original Establishment § 24.130 Change in volatile fruit-flavor concentrate operations. If the proprietor desires to make any change in the process employed to produce volatile fruit-flavor concentrate...

  2. Modeling the Volatility in Global Fertilizer Prices

    NARCIS (Netherlands)

    P-Y. Chen (Ping-Yu); C-L. Chang (Chia-Lin); C-C. Chen (Chi-Chung); M.J. McAleer (Michael)

    2010-01-01

    textabstractThe main purpose of this paper is to estimate the volatility in global fertilizer prices. The endogenous structural breakpoint unit root test and alternative volatility models, including the generalized autoregressive conditional heteroskedasticity (GARCH) model, Exponential GARCH (EGARC

  3. Fluctuation behaviors of financial return volatility duration

    Science.gov (United States)

    Niu, Hongli; Wang, Jun; Lu, Yunfan

    2016-04-01

    It is of significantly crucial to understand the return volatility of financial markets because it helps to quantify the investment risk, optimize the portfolio, and provide a key input of option pricing models. The characteristics of isolated high volatility events above certain threshold in price fluctuations and the distributions of return intervals between these events arouse great interest in financial research. In the present work, we introduce a new concept of daily return volatility duration, which is defined as the shortest passage time when the future volatility intensity is above or below the current volatility intensity (without predefining a threshold). The statistical properties of the daily return volatility durations for seven representative stock indices from the world financial markets are investigated. Some useful and interesting empirical results of these volatility duration series about the probability distributions, memory effects and multifractal properties are obtained. These results also show that the proposed stock volatility series analysis is a meaningful and beneficial trial.

  4. Characterization and semiquantitative analysis of volatiles in seedless watermelon varieties using solid-phase microextraction.

    Science.gov (United States)

    Beaulieu, John C; Lea, Jeanne M

    2006-10-04

    Seedless triploid watermelons have increased in popularity since the early 1990s, and the demand for seedless fruit is on the rise. Sweetness and sugars are crucial breeding focuses for fruit quality. Volatiles also play an important role; yet, we found no literature for seedless varieties and no reports using solid-phase microextraction (SPME) in watermelon. The objective of this experiment was to identify volatile and semivolatile compounds in five seedless watermelon varieties using carboxen divinylbenzene polydimethylsiloxane solid-phase microextraction (SPME) with gas chromatography-mass spectrometry (GC-MS). Fully ripe watermelon was squeezed through miracloth to produce rapid juice extracts for immediate headspace SPME GC-MS. Aldehydes, alcohols, ketones, and one furan (2-pentyl furan, a lipid oxidation product) were recovered. On the basis of total ion count peak area, the most abundant compounds in five varieties were 3-nonen-1-ol/(E,Z)-2,6-nonadienal (16.5-28.2%), (E)-2-nonenal (10.6-22.5%), and (Z)-6-nonenal (2.0-11.3%). Hexanal was most abundant (37.7%) in one variety (Petite Perfection) [corrected] The most abundant ketone was 6-methyl-5-hepten-2-one (2.7-7.7%). Some sensory attributes reported for these compounds are melon, citrus, cucumber, orange, rose, floral, guava, violet, vegetable, green, grassy, herbaceous, pungent, fatty, sweet, and waxy. Identifying and relating these compounds to sensory attributes will allow for future monitoring of the critical flavor compounds in seedless watermelon after processing and throughout fresh-cut storage.

  5. How to recover from the financial market flu.

    Science.gov (United States)

    Doody, Dennis

    2008-05-01

    The widely publicized subprime mortgage crisis and soaring crude oil prices have contributed to considerable market volatility in recent months, inducing queasiness among institutional investors. A four-layer approach to asset allocation that carefully considers assets, liquidity, currency, and risk may be the best strategy for maintaining an institution's financial health through today's volatile market. Perhaps the biggest challenge in such financially turbulent times is keeping fear in check.

  6. Increased resting state functional connectivity in the default mode network in recovered anorexia nervosa.

    Science.gov (United States)

    Cowdrey, Felicity A; Filippini, Nicola; Park, Rebecca J; Smith, Stephen M; McCabe, Ciara

    2014-02-01

    Functional brain imaging studies have shown abnormal neural activity in individuals recovered from anorexia nervosa (AN) during both cognitive and emotional task paradigms. It has been suggested that this abnormal activity which persists into recovery might underpin the neurobiology of the disorder and constitute a neural biomarker for AN. However, no study to date has assessed functional changes in neural networks in the absence of task-induced activity in those recovered from AN. Therefore, the aim of this study was to investigate whole brain resting state functional connectivity in nonmedicated women recovered from anorexia nervosa. Functional magnetic resonance imaging scans were obtained from 16 nonmedicated participants recovered from anorexia nervosa and 15 healthy control participants. Independent component analysis revealed functionally relevant resting state networks. Dual regression analysis revealed increased temporal correlation (coherence) in the default mode network (DMN) which is thought to be involved in self-referential processing. Specifically, compared to healthy control participants the recovered anorexia nervosa participants showed increased temporal coherence between the DMN and the precuneus and the dorsolateral prefrontal cortex/inferior frontal gyrus. The findings support the view that dysfunction in resting state functional connectivity in regions involved in self-referential processing and cognitive control might be a vulnerability marker for the development of anorexia nervosa.

  7. Business Cycles, Financial Crises, and Stock Volatility

    OpenAIRE

    G. William Schwert

    1989-01-01

    This paper shows that stock volatility increases during recessions and financial crises from 1834-1987. The evidence reinforces the notion that stock prices are an important business cycle indicator. Using two different statistical models for stock volatility, I show that volatility increases after major financial crises. Moreover. stock volatility decreases and stock prices rise before the Fed increases margin requirements. Thus, there is little reason to believe that public policies can con...

  8. Decomposing European bond and equity volatility

    DEFF Research Database (Denmark)

    Christiansen, Charlotte

    The paper investigates volatility spillover from US and aggregate European asset markets into European national asset markets. A main contribution is that bond and equity volatilities are analyzed simultaneously. A new model belonging to the "volatilityspillover" family is suggested: The conditio...... (stock) volatilities are mainly influenced by bond (stock) effects. Global, regional, and local volatility effects are all important. The introduction of the euro is associated with a structural break....

  9. The january effect across volatility regimes

    OpenAIRE

    Agnani, Betty; Aray, Henry

    2007-01-01

    Using a Markov regime switching model, this article presents evidence on the well-known January effect on stock returns. The specification allows a distinction to be drawn between two regimes, one with high volatility and other with low volatility. We obtain a time-varying January effect that is, in general, positive and significant in both volatility regimes. However, this effect is larger in the high volatility regime. In sharp contrast with most previous literature we find two major result...

  10. Possible Sources of Polar Volatiles

    Science.gov (United States)

    Schultz, P. H.

    2011-12-01

    Extensive analyses of returned Apollo samples demonstrated that the Moon is extremely volatile poor. While this conclusion remains true, various measurements since the late 90's implicated the presence of water: e.g., enhanced reflection of circularly polarized radar signals and suppression of epithermal neutrons near the poles. More recently, traces of H2O have been discovered inside volcanic glass, along with more significant amounts residing in hydrous minerals (apatite) returned from both highland and mare landing sites. Three recent lunar missions (DIXI, M3, Cassini) identified hydrous phases on/near the lunar surface, whereas the LCROSS probe detected significant quantities of volatiles (OH, H2O and other volatiles) excavated by the Centaur impact. These new mission results and sample studies, however, now allow testing different hypotheses for the generation, trapping, and replenishment of these volatiles. Solar-proton implantation must contribute to the hydrous phases in the lunar regolith in order to account for the observed time-varying abundances and occurrence near the lunar equator. This also cannot be the entire story. The relatively low speed LCROSS-Centaur impact (2.5km/s) could not vaporize such hydrous minerals, yet emissions lines of OH (from the thermal disassociation of H2O), along with other compounds (CO2, NH2) were detected within the first second, before ejecta could reach sunlight. Telescopic observations by Potter and Morgan (1985) discovered a tenuous lunar atmosphere of Na, but the LCROSS UV/Vis spectrometer did not detect the Na-D line until after the ejecta reached sunlight (along with a line pair attributed to Ag). With time, other volatile species emerged (OH, CO). The LAMP instrument on the Lunar Reconnaissance Orbiter had a different viewpoint from the side (rather than from above) and detected many other atomic species release by the LCROSS-Centaur impact. Consequently, it appears that there is a stratigraphy for trapped species

  11. A Hull and White Formula for a General Stochastic Volatility Jump-Diffusion Model with Applications to the Study of the Short-Time Behavior of the Implied Volatility

    Directory of Open Access Journals (Sweden)

    Elisa Alòs

    2008-01-01

    Full Text Available We obtain a Hull and White type formula for a general jump-diffusion stochastic volatility model, where the involved stochastic volatility process is correlated not only with the Brownian motion driving the asset price but also with the asset price jumps. Towards this end, we establish an anticipative Itô's formula, using Malliavin calculus techniques for Lévy processes on the canonical space. As an application, we show that the dependence of the volatility process on the asset price jumps has no effect on the short-time behavior of the at-the-money implied volatility skew.

  12. Volatile Survival on Near-Earth Asteroid 2008 EV5

    Science.gov (United States)

    Pohl, Leos; Britt, Daniel

    2016-10-01

    Asteroid 2008 EV5 is currently one of the possible targets of NASA Asteroid Redirect Mission (ARM). The objective of this mission is to recover a boulder from the surface of an asteroid. The selection of the final target requires understanding the physical characteristics of the asteroid such as the size-frequency distribution of boulders on the asteroid's surface, the presence of volatiles on the surface and below, the strength of the surface materials and the degree of their alteration. In our work, we focus on the second criterion, the possibility of volatiles presence on 2008 EV5. These can be expected to survive embedded within the crystal lattice of various phyllosilicates. The positive presence of volatiles on the surface of and inside the asteroid is important especially for ISRU hardware demonstrations. Spectral data suggest that 2008 EV5 is a member of CI chondrite group which is characterized by high phyllosilicate content (~70%) but there is also the possibility of it being a CR chondrite where the phyllosilicate content ranges significantly, from samples with negligible phyllosilicate content to samples with almost 70% phyllosilicate content. If the dynamical history of the asteroid brought it close enough to the Sun, the lattice of phyllosilicates could have disintegrated and released the volatiles (water) and the material could have dehydrated. The depth at which the dehydration might have taken place depends on the characteristic depth of heat wave penetration which in turn depends on material characteristics such as density, heat capacity and heat conductivity. These are in turn are closely linked to the porosity. The characteristic heat penetration depth also depends on orbital geometry and rotational and orbital periods. Besides the temperature itself, the dehydration is also affected by the duration of the crystal lattice breakup temperatures. We use thermal model in conjunction with available experimental data on the dehydration of clays and

  13. 27 CFR 20.213 - Reuse of recovered spirits.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Reuse of recovered spirits. 20.213 Section 20.213 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Alcohol, Specially Denatured Rum, or Articles § 20.213 Reuse of recovered spirits. (a) If the...

  14. Phosphorus distribution in a soil fertilized with recovered manure phosphates

    Science.gov (United States)

    Phosphorus (P) can be recovered in a concentrated form from livestock manure and poultry litter. A greenhouse study was conducted to evaluate the short-term leaching potential and plant availability of P from recovered P materials from liquid pig manure (SRP) and broiler litter (LRP) in a characteri...

  15. Language Production Abilities of Children Whose Stuttering Persisted or Recovered.

    Science.gov (United States)

    Watkins, Ruth V.; Yairi, Ehud

    1997-01-01

    A study evaluated the language production of 12 children (ages 5-8) who continued stuttering for 36 months or more after onset, 10 who recovered 18-36 months post onset, and 10 who recovered within 18 months of onset of stuttering. The majority of the children performed in the average range on measures of language production. (Author/CR)

  16. On the recovering of a coupled nonlinear Schroedinger potential

    Energy Technology Data Exchange (ETDEWEB)

    Corona, Gulmaro Corona [Area de Analisis Matematico y sus Aplicaciones, Universidad Autonoma Metropolitana, Atzcapotzalco, DF (Mexico)]. E-mail: ccg@hp9000a1.uam.mx

    2000-04-28

    We establish a priori conditions for a Gel'fand-Levitan (GL) integral using some results of the Fredholm theory. As consequence, we obtain a recovering formula for the potential of the coupled nonlinear Schroedinger equations. The remarkable fact is that the recovering formula is given in terms of the solutions of a classical GL-integral equation. (author)

  17. Beyond coherence: Recovering structured time-frequency representations

    DEFF Research Database (Denmark)

    Borup, Lasse; Gribonval, Rémi; Nielsen, Morten

    2008-01-01

    pursuit and (orthogonal) matching pursuit algorithms to recover a structured representation of an admissible signal. The sufficient conditions take into account the structure of the wavelet/Wilson dictionary and allow very large (even infinite) support sets to be recovered even though the dictionary...

  18. Oil Volatility Risk and Expected Stock Returns

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Pan, Xuhui (Nick)

    After the financialization of commodity futures markets in 2004-05 oil volatility has become a strong predictor of returns and volatility of the overall stock market. Furthermore, stocks' exposure to oil volatility risk now drives the cross-section of expected returns. The difference in average r...

  19. Volatiles in inter-specific bacterial interactions

    NARCIS (Netherlands)

    Tyc, O.; Zweers, H.; De Boer, W.; Garbeva, P.V.

    2015-01-01

    The importance of volatile organic compounds for functioning of microbes is receiving increased research attention. However, to date very little is known on how inter-specific bacterial interactions effect volatiles production as most studies have been focused on volatiles produced by monocultures o

  20. Volatiles in inter-specific bacterial interactions

    NARCIS (Netherlands)

    Tyc, O.; Zweers, H.; De Boer, W.; Garbeva, P.V.

    2015-01-01

    The importance of volatile organic compounds for functioning of microbes is receiving increased research attention. However, to date very little is known on how inter-specific bacterial interactions effect volatiles production as most studies have been focused on volatiles produced by monocultures

  1. Oil Volatility Risk and Expected Stock Returns

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Pan, Xuhui (Nick)

    After the financialization of commodity futures markets in 2004-05 oil volatility has become a strong predictor of returns and volatility of the overall stock market. Furthermore, stocks' exposure to oil volatility risk now drives the cross-section of expected returns. The difference in average r...

  2. Cost Linkages Transmit Volatility Across Markets

    DEFF Research Database (Denmark)

    Nguyen, Daniel Xuyen; Schaur, Georg

    to link the domestic and export supply costs. This theoretical contribution has two new implications for the exporting firm. First, the demand volatility in the foreign market now directly affects the firm's domestic sales volatility. Second, firms hedge domestic demand volatility with exports. The model...

  3. A new non-destructive readout by using photo-recovered surface potential contrast.

    Science.gov (United States)

    Wang, Le; Jin, Kui-juan; Gu, Jun-xing; Ma, Chao; He, Xu; Zhang, Jiandi; Wang, Can; Feng, Yu; Wan, Qian; Shi, Jin-an; Gu, Lin; He, Meng; Lu, Hui-bin; Yang, Guo-zhen

    2014-11-10

    Ferroelectric random access memory is still challenging in the feature of combination of room temperature stability, non-destructive readout and high intensity storage. As a non-contact and non-destructive information readout method, surface potential has never been paid enough attention because of the unavoidable decay of the surface potential contrast between oppositely polarized domains. That is mainly due to the recombination of the surface movable charges around the domain walls. Here, by introducing a laser beam into the combination of piezoresponse force microscopy and Kelvin probe force microscopy, we demonstrate that the surface potential contrast of BiFeO3 films can be recovered under light illumination. The recovering mechanism is understood based on the redistribution of the photo-induced charges driven by the internal electric field. Furthermore, we have created a 12-cell memory pattern based on BiFeO3 films to show the feasibility of such photo-assisted non-volatile and non-destructive readout of the ferroelectric memory.

  4. Dummies versus air puffs: efficient stimulus delivery for low-volatile odors.

    Science.gov (United States)

    Brandstaetter, Andreas Simon; Rössler, Wolfgang; Kleineidam, Christoph Johannes

    2010-05-01

    Aiming to unravel how animals perceive odors, a variety of neurophysiological techniques are used today. For olfactory stimulation, odors are commonly incorporated into a constant airstream that carries odor molecules to the receptor organ (air-delivered stimulation). Such odor delivery works well for odors of high volatility (naturally effective over long distances) but less or not at all for low-volatile odors (usually only received at short range). We developed a new odor stimulation technique especially suited for low-volatile odors and compared it with conventional air-delivered stimulation using 2 neurophysiological approaches. Odor-loaded dummies were moved into close vicinity of the receptor organs on the antenna of the Florida carpenter ant Camponotus floridanus (dummy-delivered stimulation). Neuronal activity was monitored either at receptor neuron level using electroantennography or in the first olfactory neuropile, the antennal lobes, using calcium imaging. We tested 3 odors of different volatility: C. floridanus' highly volatile alarm pheromone undecane, its low-volatile trail pheromone nerolic acid, and an even less volatile, behaviorally active C23 alkene, cis-9-tricosene. For low-volatile odors, dummy-delivered stimulation was particularly efficient. We conclude that dummy-delivered stimulation is advantageous compared to the commonly used air-delivered stimulation when studying an animal's detection and processing of low-volatile odors.

  5. Dissociation and Mass Transfer Coefficients for Ammonia Volatilization Models

    Science.gov (United States)

    Process-based models are being used to predict ammonia emissions from manure sources, but their accuracy has not been fully evaluated for cattle manure. Laboratory trials were conducted to measure the dissociation and mass transfer coefficients for ammonia volatilization from media of buffered ammon...

  6. Estimating and Forecasting Generalized Fractional Long Memory Stochastic Volatility Models

    NARCIS (Netherlands)

    S. Peiris (Shelton); M. Asai (Manabu); M.J. McAleer (Michael)

    2016-01-01

    textabstractIn recent years fractionally differenced processes have received a great deal of attention due to its flexibility in financial applications with long memory. This paper considers a class of models generated by Gegenbauer polynomials, incorporating the long memory in stochastic volatility

  7. Herbicide volatilization trumps runoff losses, a multi-year investigation

    Science.gov (United States)

    Surface runoff and volatilization are two processes critical to herbicide off-site transport. To determine the relevance of these off-site transport mechanisms, runoff and turbulent vapor fluxes were simultaneously monitored on the same site for eight years. Site location, herbicide formulations, ...

  8. Analysis of the Behavior of Volatility in Crude Oil Price

    Directory of Open Access Journals (Sweden)

    Fernando Antonio Lucena Aiube

    2014-02-01

    Full Text Available This article analyzes volatility in the spot price of crude oil. In recent years the price has also increased reaching more than US$ 140/barrel in the last decade. Moreover, the negotiated trading volume in the futures market in recent years higher than the trading volume of the earlier years. How these changes have affected the volatility in the oil prices? Does the presence of huge players, which leads to an increase in the volume under negotiation, increase volatility? Has the persistence been affected? To answer these questions, we first estimated spot prices using the two-factor model of Schwartz and Smith. With this filtering process we can capture the entire information from the future term-structure. We then analyzed the estimated spot-price series to identify the stylized facts and then adjusted conditional volatility models of GARCH family. Our findings show that the volatility in the high prices period is not different from that of low prices. The shocks behaved as transitory and the persistence in the high prices period decreased. This fact has pricing and hedging implications for short-term derivatives.

  9. 催化燃烧治理氯苯类挥发性有机化合物的最新进展%Recent process in the removal of chlorobenzenes volatile organic compounds by catalytic combustion

    Institute of Scientific and Technical Information of China (English)

    于旭霞; 冯俊小

    2016-01-01

    氯苯类(CBs)化合物的排放给环境带来严重的污染和危害。本文回顾和总结了近几年来的氯苯类挥发性有机污染物的处理方法,综述了所采用催化剂的国内外研究现状,并对不同种方法进行优缺点分析。结果表明:催化燃烧法是最具有应用前景的、最有效的处理 CBs 的技术之一,该法优势是能够在催化剂存在的条件下,高效地处理低浓度的污染物,操作温度低,避免了氮氧化物的产生。应用于催化燃烧的催化剂类型繁多,贵金属催化剂具有高活性但对高温敏感;过渡金属氧化物催化剂的抗氯中毒能力较强;钙钛矿类催化剂廉价易得,其A、B位原子具有良好的可调性,并可通过负载与改性弥补其反应温度高及易失活等缺点。与其他催化剂相对比,钙钛矿类催化剂具有更广泛的应用前景。%Emission of chlorobenzenes (CBs) substance has caused serious pollutions to our environment. This paper reviewed the approaches of treating chlorobenzene volatile organic compounds in recent years,and also summarized the research status of catalysts as well as the advantages and disadvantages of different types of methods. The results showed that catalytic combustion treatment method was one of the most promising and effective treatment techniques for CBs,because the contaminants of low concentrations could be disposed effectively with the help of catalysts at low operating temperature with no nitrogen oxides generated during the process. Many types of catalysts can be applied to the catalytic combustion. While the noble metal catalysts have high activity but sensitive to temperature,and the transition metal oxide catalysts have strong ability to resist chlorine poisoning,the perovskite-based catalysts have wider applications. Perovskite-based catalysts are inexpensive and easy to obtain,and the A and B atoms in the molecular have a good adjustability. By means of

  10. 厌氧过程挥发性脂肪酸检测中的氯离子干扰研究%Research on the chloridion interference in the anaerobic process of the detection of volatile fat acid

    Institute of Scientific and Technical Information of China (English)

    曾科; 崔燕平; 刘世豪; 张宏超

    2015-01-01

    The IC reactor has been utilized for treating straw-washing wastewater in a pulping and paper mill. While the COD volume loading rate is 1.95-4.69 kg/(m3·d),the volatile fat acid (VFA) of the reactor effluent is 192.0-533.0 mg/L. Anaerobic process reflects the acidification trend. The influences of chloridion interference while VFA is detected on the detection results are studied. After adding different amount of chloride to wastewater samples containing acetic acid with different mass concentrations ,the results show that chloridions have certain interference effect on VFA detection,and the VFA detected has all been increased. When the chloride whose concentration is less than 1 000 mg/L is added to the standard water sample whose acetic acid mass concentration is between 208.8-1 044.0 mg/L,the VFA increase values detected are all less than 40.0 mg/L and the VFA increase rates are all between 0.07%-5.07%. When the concentration of the added chloride is 1 000-5 000 mg/L,the detected interference value of VFA is less than 80 mg/L, and the VFA increase rate is between 1.50%~32.87%.%试验用 IC 反应器处理制浆洗草废水,负荷为1.95~4.69 kg/(m3·d)时,出水挥发性脂肪酸(VFA)为192.0~533.0 mg/L,厌氧过程体现酸化趋势,研究了VFA检测时氯离子的干扰对检则结果带来的影响。对含乙酸质量浓度不同的废水水样,投加不同量氯化物后检测VFA,结果表明氯离子对VFA检测有一定干扰,检测的VFA均有所增加。乙酸质量浓度为208.8~1044.0 mg/L的标准水样,投加氯化物的质量浓度小于1000 mg/L时,测定VFA的增加值均小于40.0 mg/L,VFA增加率在0.07%~5.07%;投加氯化物质量浓度在1000~5000 mg/L时,对VFA测定的干扰值未超过80.0 mg/L,VFA增加率在1.50%~32.87%。

  11. 微波超声协同萃取香草兰净油工艺优化及挥发性成分分析%Optimization of Microwave Ultrasonic Collaborative Extraction Vanilla Net Oil Process and Volatile Component Analysis

    Institute of Scientific and Technical Information of China (English)

    徐飞; 初众; 卢少芳; 谭乐和; 谷风林

    2013-01-01

    In order to optimize the technological conditions of the vanilla net oil by ultrasonic microwave collaborative extraction,the extraction efficiency were investigated of vanilla net oil using quadratic regression orthogonal rotary group legal,and gas chromatography-mass spectrum was used to identify the volatile components.The results showed that the best extraction conditions with an extraction yield 5.18% were time 6.91 min,extraction power 253 W,extraction solution petroleum ether:cyclohexane=2.8∶1 (V∶V).There were 25 components with matching degree more than 90,mainly fatty acids,alde hyde and aldehyde and esters,including linoleic acid(23.17%),lauric acid(0.07%),myristic acid(0.24%),pentadecane acid(0.28%),n-cetane acid(5.43%),9,12-octadecane diene acid ethyl ester(5.30%),palmitic acid methyl ester(0.09%)and vanillin(12.6%).The net oil had rich unique fragrance,and the optimized process could be used to improve the vanilla net oil extraction.%为优化香草兰净油超声微波协同萃取工艺条件,采用二次回归正交旋转组合设计对香草兰净油得率进行探讨,并进行气相色谱-质谱鉴定.结果表明:最佳萃取条件为萃取时间6.91 min,萃取功率253W,萃取溶液石油醚:正己烷=2.8:1(V:V),得率5.18%.匹配度达90以上的化合物有25种,其中脂肪酸、醛类及酯类含量较高,主要有亚油酸(23.17%)、月桂酸(0.07%)、肉豆蔻酸(0.24%)、十五烷酸(0.28%)、n-十六烷酸(5.43%)、9,12-十八烷二烯酸乙酯(5.30%)、棕榈酸甲酯(0.09%)、香兰素(12.6%)等.该净油具有浓郁独特的香味,优选得到的工艺可提高香草兰净油得率.

  12. Can volatile organic compounds be markers of sea salt?

    Science.gov (United States)

    Silva, Isabel; Coimbra, Manuel A; Barros, António S; Marriott, Philip J; Rocha, Sílvia M

    2015-02-15

    Sea salt is a handmade food product that is obtained by evaporation of seawater in saltpans. During the crystallisation process, organic compounds from surroundings can be incorporated into sea salt crystals. The aim of this study is to search for potential volatile markers of sea salt. Thus, sea salts from seven north-east Atlantic Ocean locations (France, Portugal, Continental Spain, Canary Islands, and Cape Verde) were analysed by headspace solid-phase microextraction combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry. A total of 165 compounds were detected, ranging from 32 to 71 compounds per salt. The volatile composition revealed the variability and individuality of each salt, and a set of ten compounds were detected in all samples. From these, seven are carotenoid-derived compounds that can be associated with the typical natural surroundings of ocean hypersaline environment. These ten compounds are proposed as potential volatile markers of sea salt.

  13. Landform Erosion and Volatile Redistribution on Ganymede and Callisto

    Science.gov (United States)

    Moore, Jeffrey Morgan; Howard, Alan D.; McKinnon, William B.; Schenk, Paul M.; Wood, Stephen E.

    2009-01-01

    We have been modeling landscape evolution on the Galilean satellites driven by volatile transport. Our work directly addresses some of the most fundamental issues pertinent to deciphering icy Galilean satellite geologic histories by employing techniques currently at the forefront of terrestrial, martian, and icy satellite landscape evolution studies [e.g., 1-6], including modeling of surface and subsurface energy and volatile exchanges, and computer simulation of long-term landform evolution by a variety of processes. A quantitative understanding of the expression and rates of landform erosion, and of volatile redistribution on landforms, is especially essential in interpreting endogenic landforms that have, in many cases, been significantly modified by erosion [e.g., 7-9].

  14. Estimating Stochastic Volatility Models using Prediction-based Estimating Functions

    DEFF Research Database (Denmark)

    Lunde, Asger; Brix, Anne Floor

    In this paper prediction-based estimating functions (PBEFs), introduced in Sørensen (2000), are reviewed and PBEFs for the Heston (1993) stochastic volatility model are derived. The finite sample performance of the PBEF based estimator is investigated in a Monte Carlo study, and compared to the p......In this paper prediction-based estimating functions (PBEFs), introduced in Sørensen (2000), are reviewed and PBEFs for the Heston (1993) stochastic volatility model are derived. The finite sample performance of the PBEF based estimator is investigated in a Monte Carlo study, and compared...... to the performance of the GMM estimator based on conditional moments of integrated volatility from Bollerslev and Zhou (2002). The case where the observed log-price process is contaminated by i.i.d. market microstructure (MMS) noise is also investigated. First, the impact of MMS noise on the parameter estimates from...

  15. Recovering biomethane and nutrients from anaerobic digestion of water hyacinth (Eichhornia crassipes) and its co-digestion with fruit and vegetable waste.

    Science.gov (United States)

    Hernández-Shek, M A; Cadavid-Rodríguez, L S; Bolaños, I V; Agudelo-Henao, A C

    2016-01-01

    The potential to recover bioenergy from anaerobic digestion of water hyacinth (WH) and from its co-digestion with fruit and vegetable waste (FVW) was investigated. Initially, biogas and methane production were studied using the biochemical methane potential (BMP) test at 2 g volatile solids (VS) L(-1) of substrate concentration, both in the digestion of WH alone and in its co-digestion with FVW (WH-FVW ratio of 70:30). Subsequently, the biogas production was optimized in terms of total solids (TS) concentration, testing 4 and 6% of TS. The BMP test showed a biogas yield of 0.114 m(3) biogas kg(-1) VSadded for WH alone. On the other hand, the biogas potential from the WH-FVW co-digestion was 0.141 m(3) biogas kg(-1) VSadded, showing an increase of 23% compared to that of WH alone. Maximum biogas production of 0.230 m(3) biogas kg(-1) VSadded was obtained at 4% of TS in the co-digestion of WH-FVW. Using semi-continuously stirred tank reactors, 1.3 m(3) biogas yield kg(-1) VSadded was produced using an organic loading rate of 2 kg VS m(-3) d(-1) and hydraulic retention time of 15 days. It was also found that a WH-FVW ratio of 80:20 improved the process in terms of pH stability. Additionally, it was found that nitrogen can be recovered in the liquid effluent with a potential for use as a liquid fertilizer.

  16. Mantle Volatiles - Distribution and Consequences

    Science.gov (United States)

    Luth, R. W.

    2003-12-01

    Volatiles in the mantle have, for many years, been the subject of intensive study from a number of perspectives. They are of interest because of their potential effects on melting relationships, on transport of major and trace elements, and on the rheological and other physical properties of the mantle. By convention, "volatiles" in this context are constituents that are liquid or gaseous at normal Earth surface conditions. This review will look at the behavior of C-O-H-S-halogen volatiles, beginning with H2O and C-O volatiles.There have been tremendous strides made recently towards understanding how volatiles in general and water in particular is transported and stored in the mantle. This progress is based on research on a number of fronts: studies of mantle-derived samples have provided insight into the nature and occurrence of hydrous phases such as amphibole, mica, and chlorite, and have provided constraints on the capacity of nominally anhydrous minerals (NAMs) such as olivine, pyroxenes, and garnet to contain "water" by a variety of substitution mechanisms. Experimental studies on mantle-derived magmas have provided constraints on volatile contents in their source regions. Other studies have constrained the pressure, temperature, and composition conditions over which hydrous phases are stable in the mantle.Fundamental questions remain about the geochemical cycling of volatiles in the mantle, and between the mantle and the surface. Much attention has focused on the capability of hydrous phases such as amphibole, mica, serpentine, chlorite, and a family of "dense hydrous magnesian silicates" (DHMSs) to act as carriers of water in subducting slabs back into the mantle. It has been clear since the work of Ito et al. (1983) that there is a discrepancy between the amount of volatiles subducted into the mantle and those returned to the surface by arc magmatism. A recent overview of volatile cycling in subduction systems by Bebout (1996) suggests that 5-15% of the H2

  17. Level Shifts in Volatility and the Implied-Realized Volatility Relation

    DEFF Research Database (Denmark)

    Christensen, Bent Jesper; de Magistris, Paolo Santucci

    to the multivariate case of the univariate level shift technique by Lu and Perron (2008). An application to the S&P500 index and a simulation experiment show that the recently documented empirical properties of strong persistence in volatility and forecastability of future realized volatility from current implied...... volatility, which have been interpreted as long memory (or fractional integration) in volatility and fractional cointegration between implied and realized volatility, are accounted for by occasional common level shifts....

  18. Stochastic model of financial markets reproducing scaling and memory in volatility return intervals

    Science.gov (United States)

    Gontis, V.; Havlin, S.; Kononovicius, A.; Podobnik, B.; Stanley, H. E.

    2016-11-01

    We investigate the volatility return intervals in the NYSE and FOREX markets. We explain previous empirical findings using a model based on the interacting agent hypothesis instead of the widely-used efficient market hypothesis. We derive macroscopic equations based on the microscopic herding interactions of agents and find that they are able to reproduce various stylized facts of different markets and different assets with the same set of model parameters. We show that the power-law properties and the scaling of return intervals and other financial variables have a similar origin and could be a result of a general class of non-linear stochastic differential equations derived from a master equation of an agent system that is coupled by herding interactions. Specifically, we find that this approach enables us to recover the volatility return interval statistics as well as volatility probability and spectral densities for the NYSE and FOREX markets, for different assets, and for different time-scales. We find also that the historical S&P500 monthly series exhibits the same volatility return interval properties recovered by our proposed model. Our statistical results suggest that human herding is so strong that it persists even when other evolving fluctuations perturbate the financial system.

  19. Fractional diffusion: recovering the distributed fractional derivative from overposed data

    Science.gov (United States)

    Rundell, W.; Zhang, Z.

    2017-03-01

    There has been considerable recent study in ‘subdiffusion’ models that replace the standard parabolic equation model by a one with a fractional derivative in the time variable. There are many ways to look at this newer approach and one such is to realize that the order of the fractional derivative is related to the time scales of the underlying diffusion process. This raises the question of what order α of derivative should be taken and if a single value actually suffices. This has led to models that combine a finite number of these derivatives each with a different fractional exponent {αk} and different weighting value c k to better model a greater possible range of time scales. Ultimately, one wants to look at a situation that combines derivatives in a continuous way—the so-called distributional model with parameter μ ≤ft(α \\right) . However all of this begs the question of how one determines this ‘order’ of differentiation. Recovering a single fractional value has been an active part of the process from the beginning of fractional diffusion modeling and if this is the only unknown then the markers left by the fractional order derivative are relatively straightforward to determine. In the case of a finite combination of derivatives this becomes much more complex due to the more limited analytic tools available for such equations, but recent progress in this direction has been made, (Li et al 2015 Appl. Math. Comput. 257 381–97, Li and Yamamoto 2015 Appl. Anal. 94 570–9). This paper considers the full distributional model where the order is viewed as a function μ ≤ft(α \\right) on the interval (0, 1]. We show existence, uniqueness and regularity for an initial-boundary value problem including an important representation theorem in the case of a single spatial variable. This is then used in the inverse problem of recovering the distributional coefficient μ ≤ft(α \\right) from a time trace of the solution and a uniqueness result is

  20. The economic value of realized volatility

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Feunou, Bruno; Jacobs, Kris

    2014-01-01

    Many studies have documented that daily realized volatility estimates based on intraday returns provide volatility forecasts that are superior to forecasts constructed from daily returns only. We investigate whether these forecasting improvements translate into economic value added. To do so, we...... develop a new class of affine discrete-time option valuation models that use daily returns as well as realized volatility. We derive convenient closed-form option valuation formulas, and we assess the option valuation properties using Standard & Poor’s (S&P) 500 return and option data. We find...... that realized volatility reduces the pricing errors of the benchmark model significantly across moneyness, maturity, and volatility levels....

  1. Volatile Sulfur Compounds from Livestock Production

    DEFF Research Database (Denmark)

    Kasper, Pernille

    2017-01-01

    Volatile sulfur compounds, i.e. hydrogen sulfide, methanethiol and dimethyl sulfide have been identified as key odorants in livestock production due to their high concentration levels and low odor threshold values. At the same time their removal with abatement technologies based on mass transfer...... and, thus, odor removal in these systems. In this context, two processes based on the absorptive oxidation of sulfur compounds in trickling filters containing metal catalysts were examined. One process with iron chelated by ethylenediaminetetraacetic acid (EDTA) was shown to remove hydrogen sulfide...... that the original sample composition was significantly impaired due to adsorption and diffusion at the walls of the measuring equipment. Generally, sulfur compounds were best preserved in both olfactometers and sample bags, while carboxylic acids, 4-methylphenol and trimethylamine were found to undergo substantial...

  2. Co-combustion of solid recovered fuels in coal-fired power plants.

    Science.gov (United States)

    Thiel, Stephanie; Thomé-Kozmiensky, Karl Joachim

    2012-04-01

    Currently, in ten coal-fired power plants in Germany solid recovered fuels from mixed municipal waste and production-specific commercial waste are co-combusted and experiments have been conducted at other locations. Overall, in 2010 approximately 800,000 tonnes of these solid recovered fuels were used. In the coming years up to 2014 a slight decline in the quantity of materials used in co-combustions is expected. The co-combustion activities are in part significantly influenced by increasing power supply from renewable sources of energy and their impact on the regime of coal-fired power plants usage. Moreover, price trends of CO₂ allowances, solid recovered fuels as well as imported coal also have significant influence. In addition to the usage of solid recovered fuels with biogenic content, the co-combustion of pure renewable biofuels has become more important in coal-fired power plants. The power plant operators make high demands on the quality of solid recovered fuels. As the operational experience shows, a set of problems may be posed by co-combustion. The key factors in process engineering are firing technique and corrosion. A significant ecological key factor is the emission of pollutants into the atmosphere. The results of this study derive from research made on the basis of an extensive literature search as well as a survey on power plant operators in Germany. The data from operators was updated in spring 2011.

  3. Arbitrage and Volatility in Chinese Stock's Markets

    Science.gov (United States)

    Lu, Shu Quan; Ito, Takao; Zhang, Jianbo

    From the point of view of no-arbitrage pricing, what matters is how much volatility the stock has, for volatility measures the amount of profit that can be made from shorting stocks and purchasing options. With the short-sales constraints or in the absence of options, however, high volatility is likely to mean arbitrage from stock market. As emerging stock markets for China, investors are increasingly concerned about volatilities of Chinese two stock markets. We estimate volatility's models for Chinese stock markets' indexes using Markov chain Monte Carlo (MCMC) method and GARCH. We find that estimated values of volatility parameters are very high for all data frequencies. It suggests that stock returns are extremely volatile even at long term intervals in Chinese markets. Furthermore, this result could be considered that there seems to be arbitrage opportunities in Chinese stock markets.

  4. Forecasting volatility of crude oil markets

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sang Hoon [Department of Business Administration, Gyeongsang National University, Jinju, 660-701 (Korea); Kang, Sang-Mok; Yoon, Seong-Min [Department of Economics, Pusan National University, Busan, 609-735 (Korea)

    2009-01-15

    This article investigates the efficacy of a volatility model for three crude oil markets - Brent, Dubai, and West Texas Intermediate (WTI) - with regard to its ability to forecast and identify volatility stylized facts, in particular volatility persistence or long memory. In this context, we assess persistence in the volatility of the three crude oil prices using conditional volatility models. The CGARCH and FIGARCH models are better equipped to capture persistence than are the GARCH and IGARCH models. The CGARCH and FIGARCH models also provide superior performance in out-of-sample volatility forecasts. We conclude that the CGARCH and FIGARCH models are useful for modeling and forecasting persistence in the volatility of crude oil prices. (author)

  5. Rand volatility and inflation in South Africa

    Directory of Open Access Journals (Sweden)

    Azwifaneli Innocentia (Mulaudzi Nemushu

    2017-01-01

    Full Text Available The floating exchange rate regime, coupled with a more open trade policy and the growth in imports, leaves South Africa vulnerable to the effects of exchange rate behaviour on import, producer and consumer prices, which all contribute to inflation. Given the central role that inflation targeting occupies in South Africa’s monetary policy, this paper examines the effect of exchange rate shocks on consumer prices using monthly data covering the period January 1994 to December 2013. Consistent with developing countries story, results show a modest exchange rate pass-through to inflation, although inflation is mainly driven by own shocks. The variance decompositions also reveal that foreign exchange rate shocks (REER contribute relatively more to inflation than money supply shocks (M3. This suggests that South African inflation process is not basically influenced by money supply changes. The practical implication is that that the volatility of the rand is not a serious threat to inflation. The SARB should therefore focus on price stability and not be unduly worried about the volatility of the rand.

  6. Chirospecific analysis of plant volatiles

    Energy Technology Data Exchange (ETDEWEB)

    Tkachev, A V [N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2007-10-31

    Characteristic features of the analysis of plant volatiles by enantioselective gas (gas-liquid) chromatography and gas chromatography/mass spectrometry are discussed. The most recent advances in the design of enantioselective stationary phases are surveyed. Examples of the preparation of the most efficient phases based on modified cyclodextrins are given. Current knowledge on the successful analytical resolution of different types of plant volatiles (aliphatic and aromatic compounds and mono-, sesqui- and diterpene derivatives) into optical antipodes is systematically described. Chiral stationary phases used for these purposes, temperature conditions and enantiomer separation factors are summarised. Examples of the enantiomeric resolution of fragrance compounds and components of plant extracts, wines and essential oils are given.

  7. Chirospecific analysis of plant volatiles

    Science.gov (United States)

    Tkachev, A. V.

    2007-10-01

    Characteristic features of the analysis of plant volatiles by enantioselective gas (gas-liquid) chromatography and gas chromatography/mass spectrometry are discussed. The most recent advances in the design of enantioselective stationary phases are surveyed. Examples of the preparation of the most efficient phases based on modified cyclodextrins are given. Current knowledge on the successful analytical resolution of different types of plant volatiles (aliphatic and aromatic compounds and mono-, sesqui- and diterpene derivatives) into optical antipodes is systematically described. Chiral stationary phases used for these purposes, temperature conditions and enantiomer separation factors are summarised. Examples of the enantiomeric resolution of fragrance compounds and components of plant extracts, wines and essential oils are given.

  8. Solid phase microextraction for profiling volatile compounds in liquered white wines

    Directory of Open Access Journals (Sweden)

    Henryk H. Jeleń

    2010-03-01

    Full Text Available Background. Profile of volatile compounds is a distinct feature of wine, which is dependent on the type of wine, grapes, fermentation and ageing processes. Profiling volatile compounds in wine using fast method provides information on major groups of compounds and can be used for classification/differentiation purposes. Solid phase microextraction (SPME was used for the profiling of volatile compounds in liquered white wines in this study. Material and methods. Different fibers were tested for this purpose: PDMS, Carboxene/ PDMS, Carboxene/DVB/PDMS, Polyacrylate, Divinylbenzene/PDMS. Different times were compared to optimize extraction process. Profile and amount of volatile compounds extracted by SPME fiber was compared for eight liquered white wines. Results. Carboxene/DVB/PDMS showed the highest efficiency in extracting higher alcohols, esters, carbonyls and terpenes. Of tested extraction times ranging from 5 to 30 min. 20 minutes was chosen providing sufficient peak responses. Using SPME total amount of volatile compounds in eight liquered wines was compared – Riversaltes, Offley Porto and Jutrzenka having the highest amount of adsorbed volatiles. Profiles of volatiles of analysed wines revealed that dominating compounds in 6 wines were esters, followed by higher alcohols, two analysed Muscat wines had high terpene contents compared to remaining wines. Conclusion. SPME can be used for relatively fast profiling of wine volatiles, that can be used for wines classification.  

  9. Volatiles in Inter-Specific Bacterial Interactions.

    Science.gov (United States)

    Tyc, Olaf; Zweers, Hans; de Boer, Wietse; Garbeva, Paolina

    2015-01-01

    The importance of volatile organic compounds for functioning of microbes is receiving increased research attention. However, to date very little is known on how inter-specific bacterial interactions effect volatiles production as most studies have been focused on volatiles produced by monocultures of well-described bacterial genera. In this study we aimed to understand how inter-specific bacterial interactions affect the composition, production and activity of volatiles. Four phylogenetically different bacterial species namely: Chryseobacterium, Dyella, Janthinobacterium, and Tsukamurella were selected. Earlier results had shown that pairwise combinations of these bacteria induced antimicrobial activity in agar media whereas this was not the case for monocultures. In the current study, we examined if these observations were also reflected by the production of antimicrobial volatiles. Thus, the identity and antimicrobial activity of volatiles produced by the bacteria were determined in monoculture as well in pairwise combinations. Antimicrobial activity of the volatiles was assessed against fungal, oomycetal, and bacterial model organisms. Our results revealed that inter-specific bacterial interactions affected volatiles blend composition. Fungi and oomycetes showed high sensitivity to bacterial volatiles whereas the effect of volatiles on bacteria varied between no effects, growth inhibition to growth promotion depending on the volatile blend composition. In total 35 volatile compounds were detected most of which were sulfur-containing compounds. Two commonly produced sulfur-containing volatile compounds (dimethyl disulfide and dimethyl trisulfide) were tested for their effect on three target bacteria. Here, we display the importance of inter-specific interactions on bacterial volatiles production and their antimicrobial activities.

  10. Volatiles in inter-specific bacterial interactions

    Directory of Open Access Journals (Sweden)

    Olaf eTyc

    2015-12-01

    Full Text Available The importance of volatile organic compounds for functioning of microbes is receiving increased research attention. However, to date very little is known on how inter-specific bacterial interactions effect volatiles production as most studies have been focused on volatiles produced by monocultures of well described bacterial genera. In this study we aimed to understand how inter-specific bacterial interactions affect the composition, production and activity of volatiles. Four phylogenetically different bacterial species namely: Chryseobacterium, Dyella, Janthinobacterium and Tsukamurella were selected. Earlier results had shown that pairwise combinations of these bacteria induced antimicrobial activity in agar media whereas this was not the case for monocultures. In the current study, we examined if these observations were also reflected by the production of antimicrobial volatiles. Thus, the identity and antimicrobial activity of volatiles produced by the bacteria were determined in monoculture as well in pairwise combinations. Antimicrobial activity of the volatiles was assessed against fungal, oomycetal and bacterial model organisms. Our results revealed that inter-specific bacterial interactions affected volatiles blend composition. Fungi and oomycetes showed high sensitivity to bacterial volatiles whereas the effect of volatiles on bacteria varied between no effects, growth inhibition to growth promotion depending on the volatile blend composition. In total 35 volatile compounds were detected most of which were sulfur-containing compounds. Two commonly produced sulfur-containing volatile compounds (dimethyl disulfide and dimethyl trisulfide were tested for their effect on three target bacteria. Here we display the importance of inter-specific interactions on bacterial volatiles production and their antimicrobial activities.

  11. Money, banks and endogenous volatility

    OpenAIRE

    Pere Gomis-Porqueras

    2000-01-01

    In this paper I consider a monetary growth model in which banks provide liquidity, and the government fixes a constant rate of money creation. There are two underlying assets in the economy, money and capital. Money is dominated in rate of return. In contrast to other papers with a larger set of government liabilities, I find a unique equilibrium when agents' risk aversion is moderate. However, indeterminacies and endogenous volatility can be observed when agents are relatively risk averse.

  12. Volatility at Karachi Stock Exchange

    OpenAIRE

    Aslam Farid; Javed Ashraf

    1995-01-01

    Frequent “crashes” of the stock market reported during the year 1994 suggest that the Karachi bourse is rapidly converting into a volatile market. This cannot be viewed as a positive sign for this developing market of South Asia. Though heavy fluctuations in stock prices are not an unusual phenomena and it has been observed at almost all big and small exchanges of the world. Focusing on the reasons for such fluctuations is instructive and likely to have important policy implications. Proponen...

  13. Influence of different salting processes on the evolution of the volatile metabolites of vacuum-packed fillets of farmed and wild sea bass (Dicentrarchus labrax) stored under refrigeration conditions: a study by SPME-GC/MS.

    Science.gov (United States)

    Vidal, Natalia P; Manzanos, María J; Goicoechea, Encarnación; Guillén, María D

    2017-02-01

    Fish shelf-life extension is a topic of great interest. In this study the behaviour of salted and unsalted farmed and wild European sea bass (Dicentrarchus labrax) fillets during storage was analysed through the evolution of their volatile metabolites. Farmed and wild sea bass fillets were brine-salted for 15 or 75 min, or dry-salted, vacuum-packed and stored at 4 °C for up to 1 month, and their headspaces were studied by Solid Phase Micro extraction-Gas Chromatography/Mass Spectrometry (SPME-GC/MS). At the same storage time, unsalted wild fillets contained, in general, a higher number and abundance of volatile compounds coming from microbiological or endogenous enzymatic activity than unsalted farmed ones. The more intense the salting, the lower the number and abundance of microbiological spoilage metabolites, especially in wild samples. The appearance of oxidation metabolites only in dry-salted wild samples evidences that this kind of salting provokes a certain oxidation in these samples. The better performance of farmed than wild fillets suggests that salted farmed fillets, vacuum-packed and stored under refrigeration conditions, could be a successful alternative to diversify the presence of sea bass in the market. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  14. Human skin volatiles: a review.

    Science.gov (United States)

    Dormont, Laurent; Bessière, Jean-Marie; Cohuet, Anna

    2013-05-01

    Odors emitted by human skin are of great interest to biologists in many fields; applications range from forensic studies to diagnostic tools, the design of perfumes and deodorants, and the ecology of blood-sucking insect vectors of human disease. Numerous studies have investigated the chemical composition of skin odors, and various sampling methods have been used for this purpose. The literature shows that the chemical profile of skin volatiles varies greatly among studies, and the use of different sampling procedures is probably responsible for some of these variations. To our knowledge, this is the first review focused on human skin volatile compounds. We detail the different sampling techniques, each with its own set of advantages and disadvantages, which have been used for the collection of skin odors from different parts of the human body. We present the main skin volatile compounds found in these studies, with particular emphasis on the most frequently studied body regions, axillae, hands, and feet. We propose future directions for promising experimental studies on odors from human skin, particularly in relation to the chemical ecology of blood-sucking insects.

  15. 硫铁矿烧渣直接还原回收有价金属%Recovering Valuable Metals from Pyrite Cinder by Direct Reduction

    Institute of Scientific and Technical Information of China (English)

    范增

    2015-01-01

    研究了采用回转短窑对硫铁矿烧渣进行焙烧以回收有价金属的方法 ,考察了不同的工艺条件对硫铁矿烧渣焙烧的影响.研究结果表明 :在还原温度在1 250℃下、还原时间为60 min下 ,硫铁矿烧渣得到充分的还原.金、银、铜、铅、锌的挥发率中试分别达到93 .26% , 82 .20% ,82 .55% ,88 .53% 和83 .48% ,此时球团的硬度可以达到2 100 N.%The roasting method was used to recover valuable metals from pyrites cinder in rotary kiln , and the influences of different process conditions on roasting pyrite cinder were examined . The results show that the pyrite cinder can be fully reduced under the conditions of reaction temperature at 400℃ and reac-tion time for 60 minutes . The volatilizing rates of gold , silver , copper , lead and zinc in pilot scale experi-ment can reach 93 .26% ,82 .20% ,82 .55% ,88 .53% and 83 .48% , respectively . Hardness of the pellets can reach 2100 N at this time .

  16. Volatile and non-volatile/semi-volatile compounds and in vitro bioactive properties of Chilean Ulmo (Eucryphia cordifolia Cav.) honey.

    Science.gov (United States)

    Acevedo, Francisca; Torres, Paulina; Oomah, B Dave; de Alencar, Severino Matias; Massarioli, Adna Prado; Martín-Venegas, Raquel; Albarral-Ávila, Vicenta; Burgos-Díaz, César; Ferrer, Ruth; Rubilar, Mónica

    2017-04-01

    Ulmo honey originating from Eucryphia cordifolia tree, known locally in the Araucania region as the Ulmo tree is a natural product with valuable nutritional and medicinal qualities. It has been used in the Mapuche culture to treat infections. This study aimed to identify the volatile and non-volatile/semi-volatile compounds of Ulmo honey and elucidate its in vitro biological properties by evaluating its antioxidant, antibacterial, antiproliferative and hemolytic properties and cytotoxicity in Caco-2 cells. Headspace volatiles of Ulmo honey were isolated by solid-phase microextraction (SPME); non-volatiles/semi-volatiles were obtained by removing all saccharides with acidified water and the compounds were identified by GC/MS analysis. Ulmo honey volatiles consisted of 50 compounds predominated by 20 flavor components. Two of the volatile compounds, lyrame and anethol have never been reported before as honey compounds. The non-volatile/semi-volatile components of Ulmo honey comprised 27 compounds including 13 benzene derivatives accounting 75% of the total peak area. Ulmo honey exhibited weak antioxidant activity but strong antibacterial activity particularly against gram-negative bacteria and methicillin-resistant Staphylococcus aureus (MRSA), the main strain involved in wounds and skin infections. At concentrations >0.5%, Ulmo honey reduced Caco-2 cell viability, released lactate dehydrogenase (LDH) and increased reactive oxygen species (ROS) production in a dose dependent manner in the presence of foetal bovine serum (FBS). The wide array of volatile and non-volatile/semi-volatile constituents of Ulmo honey rich in benzene derivatives may partly account for its strong antibacterial and antiproliferative properties important for its therapeutic use. Our results indicate that Ulmo honey can potentially inhibit cancer growth at least partly by modulating oxidative stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. A rapid column technique for trapping and collecting of volatile fungal hydrocarbons and hydrocarbon derivatives.

    Science.gov (United States)

    Booth, Eric; Strobel, Gary; Knighton, Berk; Sears, Joe; Geary, Brad; Avci, Recep

    2011-10-01

    A custom-made stainless steel column was designed to contain various materials that would trap the hydrocarbons and hydrocarbon derivatives during the processes of fungal fermentation ultimately yielding preparative amounts of volatile organic substances (VOCs). Trapping materials tested in the column were Carbotrap materials A and B (Supelco) as well as bentonite-shale from the oil bearing areas of Eastern Montana, the former allowed for the effective and efficient trapping of VOCs from purged cultures of Hypoxylon sp. Trapping efficiencies of various materials were measured by both gravimetric as well as proton transfer reaction mass spectroscopy with the Carbotraps A and B being 99% efficient when tested with known amounts of 1,8-cineole. Trapped fungal VOCs could effectively be removed and recovered via controlled heating of the stainless steel column followed by passage of the gases through a liquid nitrogen trap at a recovery rate of ca 65-70%. This method provides for the recovery of mg quantities of compounds normally present in the gas phase that may be needed for spectroscopy, bioassays and further separation and analysis and may have wide applicability for many other biological systems involving VOCs. Other available Carbotraps could be used for other applications.

  18. Bioelectrochemical recovery of waste-derived volatile fatty acids and production of hydrogen and alkali.

    Science.gov (United States)

    Zhang, Yifeng; Angelidaki, Irini

    2015-09-15

    Volatile fatty acids (VFA) are organic compounds of great importance for various industries and environmental processes. Fermentation and anaerobic digestion of organic wastes are promising alternative technologies for VFA production. However, one of the major challenges is development of sustainable downstream technologies for VFA recovery. In this study, an innovative microbial bipolar electrodialysis cell (MBEDC) was developed to meet the challenge of waste-derived VFA recovery, produce hydrogen and alkali, and potentially treat wastewater. The MBEDC was operated in fed-batch mode. At an applied voltage of 1.2 V, a VFA recovery efficiency of 98.3%, H2 of 18.4 mL and alkali production presented as pH of 12.64 were obtained using synthetic fermentation broth. The applied voltage, initial VFA concentrations and composition were affecting the VFA recovery. The energy balance revealed that net energy (5.20-6.86 kWh/kg-VFA recovered) was produced at all the applied voltages (0.8-1.4 V). The coexistence of other anionic species had no negative effect on VFA transportation. The VFA concentration was increased 2.96 times after three consecutive batches. Furthermore, the applicability of MBEDC was successfully verified with digestate. These results demonstrate for the first time the possibility of a new method for waste-derived VFA recovery and valuable products production that uses wastewater as fuel and bacteria as catalyst. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Emerging Politics of Authorship: Recovering Collectivity, Negotiating the Risk

    Directory of Open Access Journals (Sweden)

    Andrea Pisac

    2011-12-01

    Full Text Available This article examines authorship as a socially embedded process by challenging Western notions of the autonomous creative genius. It considers social interactions between various agents in the field of literary production which in turn recovers the collective nature of modern authorship. Far from leaving it unexamined, it further contextualises authorial collectivity and its role in the emerging model of authorship. Questions and arguments raised in this article are informed by the ethnographic data collected during my doctoral research focusing on the reception of post-1990s ex-Yugoslav literature on the UK book market. Such ethnographic approach to literary translations – i.e. the micro-level analysis of social interactions that ‘create’ literature – demonstrated how the author is ‘created’ in the communication of two literary systems through linguistic translation as well as re-translations of symbolic and social capitals. My research was concerned with analysing the ‘backstage’ of the publishing industry – informal networks and international literary geopolitics – which all contributed to debunking the myth of the autonomous creative genius. However, instead of retracing my steps, this article outlines new avenues and questions that such analysis has opened up. One such question is how new technologies are (reconstructing and (repositioning the role of the author.

  20. Biodiesel production from residual oils recovered from spent bleaching earth

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yi-Pin; Chang, James I. [Department of Safety, Health and Environmental Engineering, National Kaohsiung First University of Science and Technology, 1, University Blvd., Yenchao, Kaohsiung (China)

    2010-01-15

    This work was to study technical and economic feasibilities of converting residual oils recovered from spent bleaching earth generated at soybean oil refineries into useable biodiesel. Experimental results showed that fatty acids in the SBE residual oil were hexadecenoic acid (58.19%), stearic acid (21.49%) and oleic acid (20.32%), which were similar to those of vegetable oils. The methyl ester conversion via a transesterification process gave a yield between 85 and 90%. The biodiesel qualities were in reasonable agreement with both EN 14214 and ASTM D6751 standards. A preliminary financial analysis showed that the production cost of biodiesel from SBE oils was significantly lower than the pre-tax price of fossil diesel or those made of vegetable oils or waste cooking oils. The effects of the crude oil price and the investment on the production cost and the investment return period were also conducted. The result showed that the investment would return faster at higher crude oil price. (author)

  1. Neural responses to emotional faces in women recovered from anorexia nervosa.

    Science.gov (United States)

    Cowdrey, Felicity A; Harmer, Catherine J; Park, Rebecca J; McCabe, Ciara

    2012-03-31

    Impairments in emotional processing have been associated with anorexia nervosa. However, it is unknown whether neural and behavioural differences in the processing of emotional stimuli persist following recovery. The aim of this study was to investigate the neural processing of emotional faces in individuals recovered from anorexia nervosa compared with healthy controls. Thirty-two participants (16 recovered anorexia nervosa, 16 healthy controls) underwent a functional magnetic resonance imaging (fMRI) scan. Participants viewed fearful and happy emotional faces and indicated the gender of the face presented. Whole brain analysis revealed no significant differences between the groups to the contrasts of fear versus happy and vice versa. Region of interest analysis demonstrated no significant differences in the neural response to happy or fearful stimuli between the groups in the amygdala or fusiform gyrus. These results suggest that processing of emotional faces may not be aberrant after recovery from anorexia nervosa. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  2. Alienation, recovered animism and altered states of consciousness.

    Science.gov (United States)

    Charlton, Bruce G

    2007-01-01

    Alienation is the feeling that life is 'meaningless', that we do not belong in the world. But alienation is not an inevitable part of the human condition: some people do feel at one with the world as a consequence of the animistic way of thinking which is shared by children and hunter-gatherers. Animism considers all significant entities to have 'minds', to be 'alive', to be sentient agents. The animistic thinker inhabits a world populated by personal powers including not just other human beings, but also important animals and plants, and significant aspects of physical landscape. Humans belong in this world because it is a web of social relationships. Animism is therefore spontaneous, the 'natural' way of thinking for humans: all humans began as animistic children and for most of human evolutionary history would have grown into animistic adults. It requires sustained, prolonged and pervasive formal education to 'overwrite' animistic thinking with the rationalistic objectivity typical of the modern world. It is this learned abstraction that creates alienation--humans are no longer embedded in a world of social relations but become estranged, adrift in a world of indifferent things. Methods used to cure alienation and recover animistic modes of thinking involve detachment from the social systems that tend to maintain objectivity and rationality: for example, solitude, leisure, unstructured time and direct contact with nature. Many people also achieve similar results by deliberately inducing altered states of consciousness. Animistic thinking may emerge in meditation or contemplation, lucid dreaming, from self-hypnosis, when drowsy, in 'trance states' induced by repetitious rhythm or light, or when delirious due to illness, brain injury, psychoses, or intoxication with 'entheogenic' drugs--which is probably one reason for the perennial popularity of inducing intoxicated states. However, intoxication will typically damage memory processes making it harder to learn

  3. Quantitation of volatile oils in ground cumin by supercritical fluid extraction and gas chromatography with flame ionization detection.

    Science.gov (United States)

    Heikes, D L; Scott, B; Gorzovalitis, N A

    2001-01-01

    Ground cumin is used as a flavoring agent in a number of ethnic cuisines. The chemical entities, which primarily establish its characteristically pungent flavor, are found in the volatile oil of cumin. Fixed oils and carbohydrates tend to round out the harshness of the volatile oil components. However, the quantity of volatile oil is commonly the measure of the quality of this spice. For several decades, the spice industry has used a classical distillation procedure for the determination of volatile oil in cumin and other spices. However, the method is cumbersome and requires nearly 8 h to complete. Supercritical fluid extraction with capillary gas chromatography-flame ionization detection is utilized in the formulation of a rapid, accurate, and specific method for the determination of volatile oil in ground cumin. Samples are extracted in a static-dynamic mode with CO2 at 550 bar and 100 degrees C. Toluene is used as a static modifier addition. The extracted volatile oil, collected in toluene, is analyzed directly using tetradecane as the internal standard. Integration is performed as grouped peaks to include all chemical entities found in cumin volatile oil recovered from the official distillation procedure. Results from this procedure compare favorably with those obtained by the official procedure (coefficient of correlation = 0.995, 24 samples).

  4. Studies on formation of volatiles produced in the process of co-pyrolysis of xylose/proline mixtures%木糖/脯氨酸共裂解过程挥发性化合物形成规律

    Institute of Scientific and Technical Information of China (English)

    罗昌荣; 谢焰; 印黔黔; 沈世豪; 黄伟; 李炎强; 刘百战

    2013-01-01

    were also investigated and found that the ratio of xylose to proline had obvious influence on the relative proportion of pyrolysates and the present proline changed the furfural formation path when xylose was thermally degraded. The furfural was produced via Amadori products degradation path and proline only played a catalyst role in the degradation of xylose. It vanished only after the reaction with some degradation fragments. The content of total volatile compounds formed in the co-pyrolysis process of xylose was lower than that of xylose alone. Maybe due to some bigger molecules formed when xylose combined with proline, while those molecules were mainly charred. As well, the content of phenol was also decreased greatly, about 33 percent of that of xylose pyrolysed alone.

  5. What People Recovering from Alcoholism Need to Know about Osteoporosis

    Science.gov (United States)

    ... People Recovering from Alcoholism Need to Know About Osteoporosis Publication available in: PDF (76 KB) Related Resources ... Management Strategies Resources For Your Information What Is Osteoporosis? Osteoporosis is a condition in which bones become ...

  6. Improving CO2 Efficiency for Recovering Oil in Heterogeneous Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Grigg, Reid B.; Svec, Robert K.

    2003-03-10

    The work strived to improve industry understanding of CO2 flooding mechanisms with the ultimate goal of economically recovering more of the U.S. oil reserves. The principle interests are in the related fields of mobility control and injectivity.

  7. Volatility of mixed atmospheric humic-like substances and ammonium sulfate particles

    Science.gov (United States)

    Nie, Wei; Hong, Juan; Häme, Silja A. K.; Ding, Aijun; Li, Yugen; Yan, Chao; Hao, Liqing; Mikkilä, Jyri; Zheng, Longfei; Xie, Yuning; Zhu, Caijun; Xu, Zheng; Chi, Xuguang; Huang, Xin; Zhou, Yang; Lin, Peng; Virtanen, Annele; Worsnop, Douglas R.; Kulmala, Markku; Ehn, Mikael; Yu, Jianzhen; Kerminen, Veli-Matti; Petäjä, Tuukka

    2017-03-01

    The volatility of organic aerosols remains poorly understood due to the complexity of speciation and multiphase processes. In this study, we extracted humic-like substances (HULIS) from four atmospheric aerosol samples collected at the SORPES station in Nanjing, eastern China, and investigated the volatility behavior of particles at different sizes using a Volatility Tandem Differential Mobility Analyzer (VTDMA). In spite of the large differences in particle mass concentrations, the extracted HULIS from the four samples all revealed very high-oxidation states (O : C > 0.95), indicating secondary formation as the major source of HULIS in Yangtze River Delta (YRD). An overall low volatility was identified for the extracted HULIS, with the volume fraction remaining (VFR) higher than 55 % for all the regenerated HULIS particles at the temperature of 280 °C. A kinetic mass transfer model was applied to the thermodenuder (TD) data to interpret the observed evaporation pattern of HULIS, and to derive the mass fractions of semi-volatile (SVOC), low-volatility (LVOC) and extremely low-volatility components (ELVOC). The results showed that LVOC and ELVOC dominated (more than 80 %) the total volume of HULIS. Atomizing processes led to a size-dependent evaporation of regenerated HULIS particles, and resulted in more ELVOC in smaller particles. In order to understand the role of interaction between inorganic salts and atmospheric organic mixtures in the volatility of an organic aerosol, the evaporation of mixed samples of ammonium sulfate (AS) and HULIS was measured. The results showed a significant but nonlinear influence of ammonium sulfate on the volatility of HULIS. The estimated fraction of ELVOC in the organic part of the largest particles (145 nm) increased from 26 %, in pure HULIS samples, to 93 % in 1 : 3 (mass ratio of HULIS : AS) mixed samples, to 45 % in 2 : 2 mixed samples, and to 70 % in 3 : 1 mixed samples, suggesting that the interaction with ammonium sulfate

  8. Recovering a Basic Space from Issue Scales in R

    OpenAIRE

    2016-01-01

    basicspace is an R package that conducts Aldrich-McKelvey and Blackbox scaling to recover estimates of the underlying latent dimensions of issue scale data. We illustrate several applications of the package to survey data commonly used in the social sciences. Monte Carlo tests demonstrate that the procedure can recover latent dimensions and reproduce the matrix of responses at moderate levels of error and missing data.

  9. Recovering heavy rare earth metals from magnet scrap

    Energy Technology Data Exchange (ETDEWEB)

    Ott, Ryan T.; McCallum, Ralph W.; Jones, Lawrence L.

    2017-08-08

    A method of treating rare earth metal-bearing permanent magnet scrap, waste or other material in a manner to recover the heavy rare earth metal content separately from the light rare earth metal content. The heavy rare earth metal content can be recovered either as a heavy rare earth metal-enriched iron based alloy or as a heavy rare earth metal based alloy.

  10. Headspace Solid-Phase Microextraction Coupled with Gas Chromatography-Mass Spectrometric Analysis of Volatile Composition Changes of Steamed Bread during Processing%顶空固相微萃取-气质联用分析小麦馒头制作过程中的挥发性成分变化

    Institute of Scientific and Technical Information of China (English)

    燕雯; 张正茂; 刘拉平

    2012-01-01

    To study the volatile composition changes of steamed bread during processing, the volatile components in wheat flours, fermented doughs and steamed breads from three representative wheat cultivars with different gluten strength, Pubing 143, Jinmai 47 and Xinong 9817, were extracted by headspace solid-phase microextraction (HSPME) and analyzed by GC-MS. A total 23 volatile compounds (mainly naphthalene, 1-methyl-naphthalene, (Z)-2-Butenedioic acid dimethyl ester, 1,7-dimethyl- naphthalene and 2-methyl-naphthalene) were found to be common to wheat flours from "all investigated cultivars, accounting for 84.01%, 77.82% and 82.28% of the total volatile compounds in Pubing 143, Jinmai 47 and Xinong 9817, respectively. Eighteen volatile compounds (mainly ethanol, naphthalene, 1-methyl-naphthalene, butanedioic acid ethyl methyl ester and phenylethyl alcohol) were common to fermented doughs made with wheat flours from all investigated cultivars, accounting for 80.99%, 71.65% and 70.44% of the total volatile compounds in Pubing 143, Jinmai 47 and Xinong 9817, respectively. Twenty-six volatile compounds (mainly naphthalene, 1-methyl-naphthalene, 2-pentyl-furan, ethanol and nonanal) were common to steamed breads made with wheat flours from all investigated cultivars, accounting for 80.26%, 75.99% and 80.43% of the total compounds in Pubing 143, Jinmai 47 and Xinong 9817, respectively. The results obtained demonstrate that wheat flour, fermented dough and steamed bread vary in volatile composition among wheat cultivars with different gluten strength despite no difference in most of the main volatile components. During the processing of steamed bread from wheat flour; the relative content of hydrocarbons significantly decreases, whereas both the kinds and relative contents of alcohols increase, suggesting a significant change in the volatile composition.%为研究小麦挥发成分在加工过程的形成变化,选用具有代表性的3种不同

  11. Geochemical Constraints for Mechanisms of Planetary Differentiation and Volatile Depletion

    OpenAIRE

    Dhaliwal, Jasmeet Kaur

    2016-01-01

    The evolution of the terrestrial planets involved a range of complex processes, including accretion, core formation, post-core formation accretion, mantle differentiation and volatile depletion. The earliest processes of accretion and core formation have largely been overprinted on Earth and Mars, but can be investigated using geochemical measurements of extraterrestrial materials. Highly siderophile elements (HSE; Os, Ir, Ru, Rh, Pt, Pd, Re, Au) preferentially partition into metal phases an...

  12. Where do herbivore-induced plant volatiles go?

    Directory of Open Access Journals (Sweden)

    Jarmo K. Holopainen

    2013-06-01

    Full Text Available Herbivore induced plant volatiles (HIPV are specific volatile organic compounds (VOC that a plant produces in response to herbivory. Some HIPVs are only produced after damage, while others are also produced by intact plants, but in lower quantities. Among the known functions of HIPVs are within plant volatile signalling to activate systemic plant defences, the priming and activation of defences in neighbouring plants and the attraction of natural enemies of herbivores. When released into the atmosphere a plant’s control over the produced compounds ends. However, many of the HIPVs are highly reactive with atmospheric oxidants and their atmospheric life times could be relatively short, often only a few minutes. We summarise the potential ecological and atmospheric processes that involve the reaction products of HIPVs in their gaseous, liquid and solid secondary organic aerosol (SOA forms, both in the atmosphere and after deposition on plant surfaces. A potential negative feedback loop, based on the reactions forming SOA from HIPV and the associated stimulation of sun screening cloud formation is presented. This hypothesis is based on recent field surveys in the geographical areas facing greatest degree of global warming and insect outbreaks. Furthermore, we discuss how these processes could benefit the individual plant or conspecifics that originally released the HIPVs into the atmosphere. Further ecological studies should aim to elucidate the possible reasons for biosynthesis of short-lived volatile compounds to have evolved as a response to external biotic damage to plants.

  13. Factors that influence the volatile organic compound content in human breath

    NARCIS (Netherlands)

    Blanchet, L.; Smolinska, Agnieszka; Baranska, Agnieszka; Tigchelaar-Feenstra, E.; Swertz, M.; Zhernakova, A.; Dallinga, J. W.; Wijmenga, C.; van Schooten, Frederik J.

    Background. Thousands of endogenous and exogenous volatile organic compounds (VOCs) are excreted in each breath. Inflammatory and deviant metabolic processes affect the level of endogeneous VOCs, which can serve as specific biomarkers for clinical diagnosis and disease monitoring. Important issues

  14. On the source of stochastic volatility: Evidence from CAC40 index options during the subprime crisis

    Science.gov (United States)

    Slim, Skander

    2016-12-01

    This paper investigates the performance of time-changed Lévy processes with distinct sources of return volatility variation for modeling cross-sectional option prices on the CAC40 index during the subprime crisis. Specifically, we propose a multi-factor stochastic volatility model: one factor captures the diffusion component dynamics and two factors capture positive and negative jump variations. In-sample and out-of-sample tests show that our full-fledged model significantly outperforms nested lower-dimensional specifications. We find that all three sources of return volatility variation, with different persistence, are needed to properly account for market pricing dynamics across moneyness, maturity and volatility level. Besides, the model estimation reveals negative risk premium for both diffusive volatility and downward jump intensity whereas a positive risk premium is found to be attributed to upward jump intensity.

  15. Recovering activity and illusion: the nephrology day care unit.

    Science.gov (United States)

    Remón Rodríguez, C; Quirós Ganga, P L; González-Outón, J; del Castillo Gámez, R; García Herrera, A L; Sánchez Márquez, M G

    2011-01-01

    Day Care Units are an alternative to hospital care that improves more efficiency. The Nephrology, by its technical characteristics, would be benefit greatly from further development of this care modality. The objectives of this study are to present the process we have developed the Nephrology Day Care Unit in the Puerto Real University Hospital (Cádiz, Spain). For this project we followed the Deming Management Method of Quality improvement, selecting opportunities, analyzing causes, select interventions, implement and monitor results. The intervention plan includes the following points: 1) Define the place of the Day Care Unit in the organization of our Clinical Department of Nephrology, 2) Define the Manual of organization, 3) Define the structural and equipment resources, 4) Define the Catalogue of services and procedures, 5) Standards of Care Processes. Protocols and Clinical Pathways; and 6) Information and Registration System. In the first 8 months we have been performed nearly 2000 procedures, which corresponds to an average of about 10 procedures per day, and essentially related to Hemodialysis in critical or acute patients, the Interventional Nephrology, the Clinical Nephrology and Peritoneal Dialysis. The development of the Nephrology Day Care Units can help to increase our autonomy, our presence in Hospitals, recover the progressive loss of clinical activity (diagnostic and therapeutic skills) in the past to the benefit of other Specialties. It also contributes to: Promote and develop the Diagnostic and Interventional Nephrology; improve the clinical management of patients with Primary Health Level, promote the Health Education and Investigation, collaborate in the Resources Management, and finally, to make more attractive and exciting our Specialty, both for nephrologists to training specialists.

  16. [Structural recovering in Andean successional forests from Porce (Antioquia, Colombia)].

    Science.gov (United States)

    Yepes, Adriana P; del Valle, Jorge I; Jaramillo, Sandra L; Orrego, Sergio A

    2010-03-01

    Places subjected to natural or human disturbance can recover forest through an ecological process called secondary succession. Tropical succession is affected by factors such as disturbances, distance from original forest, surface configuration and local climate. These factors determine the composition of species and the time trend of the succession itself. We studied succession in soils used for cattle ranching over various decades in the Porce Region of Colombia (Andean Colombian forests). A set of twenty five permanent plots was measured, including nine plots (20 x 50 m) in primary forests and sixteen (20 x 25 m) in secondary forests. All trees with diameter > or =1.0 cm were measured. We analyzed stem density, basal area, above-ground biomass and species richness, in a successional process of ca. 43 years, and in primary forests. The secondary forests' age was estimated in previous studies, using radiocarbon dating, aerial photographs and a high-resolution satellite image analysis (7 to >43 years). In total, 1,143 and 1,766 stems were measured in primary and secondary forests, respectively. Basal area (5.7 to 85.4 m2 ha(-1)), above-ground biomass (19.1 to 1,011.5 t ha(-1)) and species richness (4 to 69) directly increased with site age, while steam density decreased (3,180 to 590). Diametric distributions were "J-inverted" for primary forests and even-aged size-class structures for secondary forests. Three species of palms were abundant and exclusive in old secondary forests and primary forests: Oenocarpus mapora, Euterpe precatoria and Oenocarpus bataua. These palms happened in cohorts after forest disturbances. Secondary forest structure was 40% in more than 43 years of forest succession and indicate that many factors are interacting and affecting the forests succession in the area (e.g. agriculture, cattle ranching, mining, etc.).

  17. Origin of Volatiles in Earth: Indigenous Versus Exogenous Sources Based on Highly Siderophile, Volatile Siderophile, and Light Volatile Elements

    Science.gov (United States)

    Righter, K.; Danielson, L.; Pando, K. M.; Marin, N.; Nickodem, K.

    2015-01-01

    Origin of Earth's volatiles has traditionally been ascribed to late accretion of material after major differentiation events - chondrites, comets, ice or other exogenous sources. A competing theory is that the Earth accreted its volatiles as it was built, thus water and other building blocks were present early and during differentiation and core formation (indigenous). Here we discuss geochemical evidence from three groups of elements that suggests Earth's volatiles were acquired during accretion and did not require additional sources after differentiation.

  18. Prediction error and somatosensory insula activation in women recovered from anorexia nervosa.

    Science.gov (United States)

    Frank, Guido K W; Collier, Shaleise; Shott, Megan E; O'Reilly, Randall C

    2016-08-01

    Previous research in patients with anorexia nervosa showed heightened brain response during a taste reward conditioning task and heightened sensitivity to rewarding and punishing stimuli. Here we tested the hypothesis that individuals recovered from anorexia nervosa would also experience greater brain activation during this task as well as higher sensitivity to salient stimuli than controls. Women recovered from restricting-type anorexia nervosa and healthy control women underwent fMRI during application of a prediction error taste reward learning paradigm. Twenty-four women recovered from anorexia nervosa (mean age 30.3 ± 8.1 yr) and 24 control women (mean age 27.4 ± 6.3 yr) took part in this study. The recovered anorexia nervosa group showed greater left posterior insula activation for the prediction error model analysis than the control group (family-wise error- and small volume-corrected p anorexia nervosa than controls for unexpected stimulus omission, but not for unexpected receipt. Sensitivity to punishment was elevated in women recovered from anorexia nervosa. This was a cross-sectional study, and the sample size was modest. Anorexia nervosa after recovery is associated with heightened prediction error-related brain response in the posterior insula as well as greater response to unexpected reward stimulus omission. This finding, together with behaviourally increased sensitivity to punishment, could indicate that individuals recovered from anorexia nervosa are particularly responsive to punishment. The posterior insula processes somatosensory stimuli, including unexpected bodily states, and greater response could indicate altered perception or integration of unexpected or maybe unwanted bodily feelings. Whether those findings develop during the ill state or whether they are biological traits requires further study.

  19. The origin of volatiles in the Earth's mantle

    Science.gov (United States)

    Hier-Majumder, Saswata; Hirschmann, Marc M.

    2017-08-01

    that the mantle stored substantially higher amounts of volatiles than previously thought, thanks to large quantities of melt trapped in the mantle due to rapid freezing of the magma ocean. Our models show that up to 77% of the total planetary budget of water and 12% of CO2 can be stored in the mantle due to this previously unaccounted process.

  20. Differentiation of lemon essential oil based on volatile and non-volatile fractions with various analytical techniques: a metabolomic approach.

    Science.gov (United States)

    Mehl, Florence; Marti, Guillaume; Boccard, Julien; Debrus, Benjamin; Merle, Philippe; Delort, Estelle; Baroux, Lucie; Raymo, Vilfredo; Velazco, Maria Inés; Sommer, Horst; Wolfender, Jean-Luc; Rudaz, Serge

    2014-01-15

    Due to the importance of citrus lemon oil for the industry, fast and reliable analytical methods that allow the authentication and/or classification of such oil, using the origin of production or extraction process, are necessary. To evaluate the potential of volatile and non-volatile fractions for classification purposes, volatile compounds of cold-pressed lemon oils were analyzed, using GC-FID/MS and FT-MIR, while the non-volatile residues were studied, using FT-MIR, (1)H-NMR and UHPLC-TOF-MS. 64 Lemon oil samples from Argentina, Spain and Italy were considered. Unsupervised and supervised multivariate analyses were sequentially performed on various data blocks obtained by the above techniques. Successful data treatments led to statistically significant models that discriminated and classified cold-pressed lemon oils according to their geographic origin, as well as their production processes. Studying the loadings allowed highlighting of important classes of discriminant variables that corresponded to putative or identified chemical functions and compounds.