WorldWideScience

Sample records for review understanding sorbent

  1. Oil sorbents from plastic wastes and polymers: A review.

    Science.gov (United States)

    Saleem, Junaid; Adil Riaz, Muhammad; Gordon, McKay

    2018-01-05

    A large volume of the waste produced across the world is composed of polymers from plastic wastes such as polyethylene (HDPE or LDPE), polypropylene (PP), and polyethylene terephthalate (PET) amongst others. For years, environmentalists have been looking for various ways to overcome the problems of such large quantities of plastic wastes being disposed of into landfill sites. On the other hand, the usage of synthetic polymers as oil sorbents in particular, polyolefins, including polypropylene (PP) and polyethylene (PE) have been reported. In recent years, the idea of using plastic wastes as the feed for the production of oil sorbents has gained momentum. However, the studies undertaking such feasibility are rather scattered. This review paper is the first of its kind reporting, compiling and reviewing these various processes. The production of an oil sorbent from plastic wastes is being seen to be satisfactorily achievable through a variety of methods Nevertheless, much work needs to be done regarding further investigation of the numerous parameters influencing production yields and sorbent qualities. For example, differences in results are seen due to varying operating conditions, experimental setups, and virgin or waste plastics being used as feeds. The field of producing oil sorbents from plastic wastes is still very open for further research, and seems to be a promising route for both waste reduction, and the synthesis of value-added products such as oil sorbents. In this review, the research related to the production of various oil sorbents based on plastics (plastic waste and virgin polymer) has been discussed. Further oil sorbent efficiency in terms of oil sorption capacity has been described. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Lime-Based Sorbents for High-Temperature CO2 Capture—A Review of Sorbent Modification Methods

    Science.gov (United States)

    Manovic, Vasilije; Anthony, Edward J.

    2010-01-01

    This paper presents a review of the research on CO2 capture by lime-based looping cycles undertaken at CanmetENERGY’s (Ottawa, Canada) research laboratories. This is a new and very promising technology that may help in mitigation of global warming and climate change caused primarily by the use of fossil fuels. The intensity of the anticipated changes urgently requires solutions such as more cost-effective technologies for CO2 capture. This new technology is based on the use of lime-based sorbents in a dual fluidized bed combustion (FBC) reactor which contains a carbonator—a unit for CO2 capture, and a calciner—a unit for CaO regeneration. However, even though natural materials are cheap and abundant and very good candidates as solid CO2 carriers, their performance in a practical system still shows significant limitations. These limitations include rapid loss of activity during the capture cycles, which is a result of sintering, attrition, and consequent elutriation from FBC reactors. Therefore, research on sorbent performance is critical and this paper reviews some of the promising ways to overcome these shortcomings. It is shown that reactivation by steam/water, thermal pre-treatment, and doping simultaneously with sorbent reforming and pelletization are promising potential solutions to reduce the loss of activity of these sorbents over multiple cycles of use. PMID:20948952

  3. Lime-Based Sorbents for High-Temperature CO2 Capture—A Review of Sorbent Modification Methods

    Directory of Open Access Journals (Sweden)

    Edward J. Anthony

    2010-08-01

    Full Text Available This paper presents a review of the research on CO2 capture by lime-based looping cycles undertaken at CanmetENERGY’s (Ottawa, Canada research laboratories. This is a new and very promising technology that may help in mitigation of global warming and climate change caused primarily by the use of fossil fuels. The intensity of the anticipated changes urgently requires solutions such as more cost-effective technologies for CO2 capture. This new technology is based on the use of lime-based sorbents in a dual fluidized bed combustion (FBC reactor which contains a carbonator—a unit for CO2 capture, and a calciner—a unit for CaO regeneration. However, even though natural materials are cheap and abundant and very good candidates as solid CO2 carriers, their performance in a practical system still shows significant limitations. These limitations include rapid loss of activity during the capture cycles, which is a result of sintering, attrition, and consequent elutriation from FBC reactors. Therefore, research on sorbent performance is critical and this paper reviews some of the promising ways to overcome these shortcomings. It is shown that reactivation by steam/water, thermal pre-treatment, and doping simultaneously with sorbent reforming and pelletization are promising potential solutions to reduce the loss of activity of these sorbents over multiple cycles of use.

  4. Engineering metal (hydr)oxide sorbents for removal of arsenate and similar weak-acid oxyanion contaminants: A critical review with emphasis on factors governing sorption processes.

    Science.gov (United States)

    Hristovski, Kiril D; Markovski, Jasmina

    2017-11-15

    To create an integrative foundation for engineering of the next generation inexpensive sorbent systems, this critical review addresses the existing knowledge gap in factor/performance relationships between weak-acid oxyanion contaminants and metal (hydr)oxide sorbents. In-depth understanding of fundamental thermodynamics and kinetics mechanisms, material fabrication, and analytical and characterization techniques, is necessary to engineer sorbent that exhibit high capacity, selectivity, stability, durability and mass transport of contaminants under a wide range of operating and water matrix conditions requirements. From the perspective of thermodynamics and kinetics, this critical review examines the factors affecting sorbent performances and analyzes the existing research to elucidate future directions aimed at developing novel sorbents for removal of weak-acid oxyanion contaminants from water. Only sorbents that allow construction of simple and inexpensive water treatment systems adapted to overcome fiscal and technological barriers burdening small communities could pave the road for providing inexpensive potable water to millions of people. Novel sorbents, which exhibit (1) poor performances in realistic operating and water matrix conditions and/or (2) do not comply with the purely driven economics factors of production scalability or cost expectations, are predestined to never be commercialized. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Solid amine sorbents for CO2 capture by chemical adsorption: A review

    Directory of Open Access Journals (Sweden)

    Elif Erdal Ünveren

    2017-03-01

    Full Text Available Amines are well-known for their reversible reactions with CO2, which make them ideal for CO2 capture from several gas streams, including flue gas. In this respect, selective CO2 absorption by aqueous alkanolamines is the most mature technology but the process is energy intensive and has also corrosion problems. Both disadvantages can be diminished to a certain extent by chemical adsorption of CO2 selectively. The most important element of the chemical adsorption of CO2 involves the design and development of a suitable adsorbent which consist of a porous support onto which an amine is attached or immobilized. Such an adsorbent is often called as solid amine sorbent. This review covers solid amine-based studies which are developed and published in recent years. First, the review examines several different types of porous support materials, namely, three mesoporous silica (MCM-41, SBA-15 and KIT-6 and two polymeric supports (PMMA and PS for CO2 adsorption. Emphasis is given to the synthesis, modifications and characterizations -such as BET and PXRD data-of them. Amination of these supports to obtain a solid amine sorbent through impregnation or grafting is reviewed comparatively. Focus is given to the adsorption mechanisms, material characteristics, and synthesis methods which are discussed in detail. Significant amount of original data are also presented which makes this review unique. Finally, relevant CO2 adsorption (or equilibrium capacity data, and cyclic adsorption/desorption performance and stability of important classes of solid amine sorbents are critically reviewed. These include severa PEI or TEPA impregnated adsorbents and APTES-grafted systems.

  6. Sorbents for mercury removal from flue gas

    Energy Technology Data Exchange (ETDEWEB)

    Granite, Evan J.; Hargis, Richard A.; Pennline, Henry W.

    1998-01-01

    A review of the various promoters and sorbents examined for the removal of mercury from flue gas is presented. Commercial sorbent processes are described along with the chemistry of the various sorbent-mercury interactions. Novel sorbents for removing mercury from flue gas are suggested. Since activated carbons are expensive, alternate sorbents and/or improved activated carbons are needed. Because of their lower cost, sorbent development work can focus on base metal oxides and halides. Additionally, the long-term sequestration of the mercury on the sorbent needs to be addressed. Contacting methods between the flue gas and the sorbent also merit investigation.

  7. Aerogel sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Begag, Redouane; Rhine, Wendell E.; Dong, Wenting

    2018-04-03

    The current invention describes methods and compositions of various sorbents based on aerogels of various silanes and their use as sorbent for carbon dioxide. Methods further provide for optimizing the compositions to increase the stability of the sorbents for prolonged use as carbon dioxide capture matrices.

  8. Application of Mineral Sorbents for Removal of Petroleum Substances: A Review

    Directory of Open Access Journals (Sweden)

    Lidia Bandura

    2017-03-01

    Full Text Available Environmental pollution with petroleum products has become a major problem worldwide, and is a consequence of industrial growth. The development of sustainable methods for the removal of petroleum substances and their derivatives from aquatic and terrestrial environments and from air has therefore become extremely important today. Advanced technologies and materials dedicated to this purpose are relatively expensive; sorption methods involving mineral sorbents are therefore popular and are widely described in the scientific literature. Mineral materials are easily available, low-cost, universal adsorbents and have a number of properties that make them suitable for the removal of petroleum substances. This review describes recent works on the use of natural, synthetic and modified mineral adsorbents for the removal of petroleum substances and their derivatives from roads, water and air.

  9. Application of polyurethane foam as a sorbent for trace metal pre-concentration — A review

    Science.gov (United States)

    Lemos, V. A.; Santos, M. S.; Santos, E. S.; Santos, M. J. S.; dos Santos, W. N. L.; Souza, A. S.; de Jesus, D. S.; das Virgens, C. F.; Carvalho, M. S.; Oleszczuk, N.; Vale, M. G. R.; Welz, B.; Ferreira, S. L. C.

    2007-01-01

    The first publication on the use of polyurethane foam (PUF) for sorption processes dates back to 1970, and soon after the material was applied for separation processes. The application of PUF as a sorbent for solid phase extraction of inorganic analytes for separation and pre-concentration purposes is reviewed. The physical and chemical characteristics of PUF (polyether and polyester type) are discussed and an introduction to the characterization of these sorption processes using different types of isotherms is given. Separation and pre-concentration methods using unloaded and loaded PUF in batch and on-line procedures with continuous flow and flow injection systems are presented. Methods for the direct solid sampling analysis of the PUF after pre-concentration are discussed as well as approaches for speciation analysis. Thermodynamic proprieties of some extraction processes are evaluated and the interpretation of determined parameters, such as enthalpy, entropy and Gibbs free energy in light of the physico-chemical processes is explained.

  10. Sorbent Scoping Studies

    International Nuclear Information System (INIS)

    Chancellor, Christopher John

    2016-01-01

    The Los Alamos National Laboratory-Carlsbad Operations (LANL-CO) office was tasked by the DOE CBFO, Office of the Manager to perform a review of the acceptable knowledge (AK) to identify the oxidizers and sorbents in transuranic (TRU) waste streams, to conduct scoping studies on the oxidizers and sorbents identified in AK review to inform the Quality Level 1 (QL1) testing, and to conduct a series of QL1 tests to provide the scientific data to support a basis of knowledge document for determining the criteria for (1) accepting waste at the Waste Isolation Pilot Plant (WIPP) without treatment, (2) determining waste that will require treatment, and (3) if treatment is required, how the treatment must be performed. The purpose of this report is to present the results of the AK review of sorbents present in active waste streams, provide a technical analysis of the sorbent list, report the results of the scoping studies for the fastest-burning organic sorbent, and provide the list of organic and inorganic sorbents to be used in the development of a Test Plan for Preparation and Testing of Sorbents Mixed with Oxidizer found in Transuranic Waste (DWT-TP-001). The companion report, DWT-RPT-001, Oxidizer Scoping Studies, has similar information for oxidizers identified during the AK review of TRU waste streams. The results of the oxidizer and sorbent scoping studies will be used to inform the QL1 test plan. The QL1 test results will support the development of a basis of knowledge document that will evaluate oxidizing chemicals and sorbents in TRU waste and provide guidance for treatment.

  11. Sorbent Scoping Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chancellor, Christopher John [Los Alamos National Lab. (LANL), Carlsbad, NM (United States). Difficult Waste Team

    2016-11-14

    The Los Alamos National Laboratory–Carlsbad Operations (LANL-CO) office was tasked by the DOE CBFO, Office of the Manager to perform a review of the acceptable knowledge (AK) to identify the oxidizers and sorbents in transuranic (TRU) waste streams, to conduct scoping studies on the oxidizers and sorbents identified in AK review to inform the Quality Level 1 (QL1) testing, and to conduct a series of QL1 tests to provide the scientific data to support a basis of knowledge document for determining the criteria for (1) accepting waste at the Waste Isolation Pilot Plant (WIPP) without treatment, (2) determining waste that will require treatment, and (3) if treatment is required, how the treatment must be performed. The purpose of this report is to present the results of the AK review of sorbents present in active waste streams, provide a technical analysis of the sorbent list, report the results of the scoping studies for the fastest-burning organic sorbent, and provide the list of organic and inorganic sorbents to be used in the development of a Test Plan for Preparation and Testing of Sorbents Mixed with Oxidizer found in Transuranic Waste (DWT-TP-001). The companion report, DWT-RPT-001, Oxidizer Scoping Studies, has similar information for oxidizers identified during the AK review of TRU waste streams. The results of the oxidizer and sorbent scoping studies will be used to inform the QL1 test plan. The QL1 test results will support the development of a basis of knowledge document that will evaluate oxidizing chemicals and sorbents in TRU waste and provide guidance for treatment.

  12. Sorbent suppliers

    International Nuclear Information System (INIS)

    Vedder, M.

    1994-01-01

    Sorbents are used to absorb or contain spilled and leaking chemicals, oils, lubricants and other process fluids. They are commonly used around the base of machinery in industrial applications, and in remediating oil spills on land and water. Sorbents are made from biodegradable, inorganic or synthetic materials. Organic materials include corn cobs, wood pulp, paper fiber and cotton. Inorganic materials include clay, perlite, expanded silicates and expanded mica. Synthetic sorbents are made from petroleum- or plastic-based materials such as polyurethane, polyethylene or polypropylene. Sorbents are available in a variety of forms, including pads, rolls, booms, pillows and loose particulate

  13. Understanding Mathematics-A Review

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 5. Understanding Mathematics – A Review. Shashidhar Jagadeeshan. Book Review Volume 6 Issue 5 May ... Author Affiliations. Shashidhar Jagadeeshan1. Centre for Learning, 469, 9th Cross, 1st Block, Jayanagar, Bangalore 560 011, India.

  14. The use of solid sorbents for direct accumulation of organic compounds from water matrices : a review of solid-phase extraction techniques

    NARCIS (Netherlands)

    Liska, I.; Krupcik, J.; Leclercq, P.A.

    1989-01-01

    The main principles of solid-phase extraction techniques are reviewed in this paper. Various solid sorbents can be used as a suitable trap for direct accumulation of organic compounds from aqueous solutions. The trapped analytes can be desorbed by elution with suitably chosen liquid phases. These

  15. Understanding Athletic Pubalgia: A Review.

    Science.gov (United States)

    Cohen, Brian; Kleinhenz, Dominic; Schiller, Jonathan; Tabaddor, Ramin

    2016-10-04

    Athletic Pubalgia, more commonly known as sports hernia, is defined as chronic lower abdominal and groin pain without the presence of a true hernia. It is increasingly recognized in athletes as a source of groin pain and is often associated with other pathology. A comprehensive approach to the physical exam and a strong understanding of hip and pelvic anatomy are critical in making the appropriate diagnosis. Various management options are available. We review the basic anatomy, patholophysiology, diagnostic approach and treatment of athletic pubalgia as well as discuss associated conditions such as femoroacetabular impingement. [Full article available at http://rimed.org/rimedicaljournal-2016-10.asp].

  16. A critical review of microextraction by packed sorbent as a sample preparation approach in drug bioanalysis.

    Science.gov (United States)

    Alves, Gilberto; Rodrigues, Márcio; Fortuna, Ana; Falcão, Amílcar; Queiroz, João

    2013-06-01

    Sample preparation is widely accepted as the most labor-intensive and error-prone part of the bioanalytical process. The recent advances in this field have been focused on the miniaturization and integration of sample preparation online with analytical instrumentation, in order to reduce laboratory workload and increase analytical performance. From this perspective, microextraction by packed sorbent (MEPS) has emerged in the last few years as a powerful sample preparation approach suitable to be easily automated with liquid and gas chromatographic systems applied in a variety of bioanalytical areas (pharmaceutical, clinical, toxicological, environmental and food research). This paper aims to provide an overview and a critical discussion of recent bioanalytical methods reported in literature based on MEPS, with special emphasis on those developed for the quantification of therapeutic drugs and/or metabolites in biological samples. The advantages and some limitations of MEPS, as well as its comparison with other extraction techniques, are also addressed herein.

  17. Carbon nanotubes as solid-phase extraction sorbents prior to atomic spectrometric determination of metal species: A review

    Energy Technology Data Exchange (ETDEWEB)

    Herrero Latorre, C., E-mail: carlos.herrero@usc.es [Universidad de Santiago de Compostela, Dpto. Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Alfonso X el Sabio s/n, 27002 Lugo (Spain); Alvarez Mendez, J.; Barciela Garcia, J.; Garcia Martin, S.; Pena Crecente, R.M. [Universidad de Santiago de Compostela, Dpto. Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Alfonso X el Sabio s/n, 27002 Lugo (Spain)

    2012-10-24

    Highlights: Black-Right-Pointing-Pointer The use of CNTs as sorbent for metal species in solid phase extraction has been described. Black-Right-Pointing-Pointer Physical and chemical strategies for functionalization of carbon nanotubes have been discussed. Black-Right-Pointing-Pointer Published analytical methods concerning solid phase extraction and atomic spectrometric determination have been reviewed. - Abstract: New materials have significant impact on the development of new methods and instrumentation for chemical analysis. From the discovery of carbon nanotubes in 1991, single and multi-walled carbon nanotubes - due to their high adsorption and desorption capacities - have been employed as sorption substrates in solid-phase extraction for the preconcentration of metal species from diverse matrices. Looking for successive improvements in sensitivity and selectivity, in the past few years, carbon nanotubes have been utilized as sorbents for solid phase extraction in three different ways: like as-grown, oxidized and functionalized nanotubes. In the present paper, an overview of the recent trends in the use of carbon nanotubes for solid phase extraction of metal species in environmental, biological and food samples is presented. The determination procedures involved the adsorption of metals on the nanotube surface, their quantitative desorption and subsequent measurement by means of atomic spectrometric techniques such as flame atomic absorption spectrometry, electrothermal atomic absorption spectrometry or inductively coupled plasma atomic emission spectrometry/mass spectrometry, among others. Synthesis, purification and types of carbon nanotubes, as well as the diverse chemical and physical strategies for their functionalization are described. Based on 140 references, the performance and general properties of the applications of solid phase extraction based on carbon nanotubes for metal species atomic spectrometric determination are discussed.

  18. Carbon nanotubes as solid-phase extraction sorbents prior to atomic spectrometric determination of metal species: A review

    International Nuclear Information System (INIS)

    Herrero Latorre, C.; Álvarez Méndez, J.; Barciela García, J.; García Martín, S.; Peña Crecente, R.M.

    2012-01-01

    Highlights: ► The use of CNTs as sorbent for metal species in solid phase extraction has been described. ► Physical and chemical strategies for functionalization of carbon nanotubes have been discussed. ► Published analytical methods concerning solid phase extraction and atomic spectrometric determination have been reviewed. - Abstract: New materials have significant impact on the development of new methods and instrumentation for chemical analysis. From the discovery of carbon nanotubes in 1991, single and multi-walled carbon nanotubes – due to their high adsorption and desorption capacities – have been employed as sorption substrates in solid-phase extraction for the preconcentration of metal species from diverse matrices. Looking for successive improvements in sensitivity and selectivity, in the past few years, carbon nanotubes have been utilized as sorbents for solid phase extraction in three different ways: like as-grown, oxidized and functionalized nanotubes. In the present paper, an overview of the recent trends in the use of carbon nanotubes for solid phase extraction of metal species in environmental, biological and food samples is presented. The determination procedures involved the adsorption of metals on the nanotube surface, their quantitative desorption and subsequent measurement by means of atomic spectrometric techniques such as flame atomic absorption spectrometry, electrothermal atomic absorption spectrometry or inductively coupled plasma atomic emission spectrometry/mass spectrometry, among others. Synthesis, purification and types of carbon nanotubes, as well as the diverse chemical and physical strategies for their functionalization are described. Based on 140 references, the performance and general properties of the applications of solid phase extraction based on carbon nanotubes for metal species atomic spectrometric determination are discussed.

  19. Understanding mitochondrial myopathies: a review

    Directory of Open Access Journals (Sweden)

    Abhimanyu S. Ahuja

    2018-05-01

    Full Text Available Mitochondria are small, energy-producing structures vital to the energy needs of the body. Genetic mutations cause mitochondria to fail to produce the energy needed by cells and organs which can cause severe disease and death. These genetic mutations are likely to be in the mitochondrial DNA (mtDNA, or possibly in the nuclear DNA (nDNA. The goal of this review is to assess the current understanding of mitochondrial diseases. This review focuses on the pathology, causes, risk factors, symptoms, prevalence data, symptomatic treatments, and new research aimed at possible preventions and/or treatments of mitochondrial diseases. Mitochondrial myopathies are mitochondrial diseases that cause prominent muscular symptoms such as muscle weakness and usually present with a multitude of symptoms and can affect virtually all organ systems. There is no cure for these diseases as of today. Treatment is generally supportive and emphasizes symptom management. Mitochondrial diseases occur infrequently and hence research funding levels tend to be low in comparison with more common diseases. On the positive side, quite a few genetic defects responsible for mitochondrial diseases have been identified, which are in turn being used to investigate potential treatments. Speech therapy, physical therapy, and respiratory therapy have been used in mitochondrial diseases with variable results. These therapies are not curative and at best help with maintaining a patient’s current abilities to move and function.

  20. Desulfurization sorbent regeneration

    Science.gov (United States)

    Jalan, V.M.; Frost, D.G.

    1982-07-07

    A spent solid sorbent resulting from the removal of hydrogen sulfide from a fuel gas flow is regenerated with a steam-air mixture. The mixture of steam and air may also include additional nitrogen or carbon dioxide. The gas mixture contacts the spent sorbent containing metal sulfide at a temperature above 500/sup 0/C to regenerate the sulfide to metal oxide or carbonate. Various metal species including the period four transition metals and the lanthanides are suitable sorbents that may be regenerated by this method. In addition, the introduction of carbon dioxide gas permits carbonates such as those of strontium, barium and calcium to be regenerated. The steam permits regeneration of spent sorbent without formation of metal sulfate. Moreover, the regeneration will proceed with low oxygen concentrations and will occur without the increase in temperature to minimize the risk of sintering and densification of the sorbent. This method may be used for high-temperature fuel cells.

  1. Fundamental mechanisms in flue-gas conditioning. Topical report No. 1, Literature review and assembly of theories on the interactions of ash and FGD sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Dahlin, R.S.; Vann Bush, P.; Snyder, T.R.

    1992-01-09

    The overall goal of this research project is to formulate a mathematical model of flue gas conditioning. This model will be based on an understanding of why ash properties, such as cohesivity and resistivity, are changed by conditioning. Such a model could serve as a component of the performance models of particulate control devices where flue gas conditioning is used. There are two specific objectives of this research project, which divide the planned research into two main parts. One part of the project is designed to determine how ash particles are modified by interactions with sorbent injection processes and to describe the mechanisms by which these interactions affect fine particle collection. The objective of the other part of the project is to identify the mechanisms by which conditioning agents, including chemically active compounds, modify the key properties of fine fly ash particles.

  2. Mercury removal sorbents

    Science.gov (United States)

    Alptekin, Gokhan

    2016-03-29

    Sorbents and methods of using them for removing mercury from flue gases over a wide range of temperatures are disclosed. Sorbent materials of this invention comprise oxy- or hydroxyl-halogen (chlorides and bromides) of manganese, copper and calcium as the active phase for Hg.sup.0 oxidation, and are dispersed on a high surface porous supports. In addition to the powder activated carbons (PACs), this support material can be comprised of commercial ceramic supports such as silica (SiO.sub.2), alumina (Al.sub.2O.sub.3), zeolites and clays. The support material may also comprise of oxides of various metals such as iron, manganese, and calcium. The non-carbon sorbents of the invention can be easily injected into the flue gas and recovered in the Particulate Control Device (PCD) along with the fly ash without altering the properties of the by-product fly ash enabling its use as a cement additive. Sorbent materials of this invention effectively remove both elemental and oxidized forms of mercury from flue gases and can be used at elevated temperatures. The sorbent combines an oxidation catalyst and a sorbent in the same particle to both oxidize the mercury and then immobilize it.

  3. Space-filling polyhedral sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Haaland, Peter

    2016-06-21

    Solid sorbents, systems, and methods for pumping, storage, and purification of gases are disclosed. They derive from the dynamics of porous and free convection for specific gas/sorbent combinations and use space filling polyhedral microliths with facial aplanarities to produce sorbent arrays with interpenetrating interstitial manifolds of voids.

  4. PROCEEDINGS: MULTIPOLLUTANT SORBENT REACTIVITY ...

    Science.gov (United States)

    The report is a compilation of technical papers and visual aids presented by representatives of industry, academia, and government agencies at a workshop on multipollutant sorbent reactivity that was held at EPA's Environmental Research Center in Research Triangle Park, NC, on July 19-20, 1994. There were 16 technical presentations in three sessions, and a panel discussion between six research experts. The workshop was a forum for the exchange of ideas and information on the use of sorbents to control air emissions of acid gases (sulfur dioxide, nitrogen oxides, and hydrogen chloride); mercury and dioxins; and toxic metals, primarily from fossil fuel combustion. A secondary purpose for conducting the workshop was to help guide EPA's research planning activities. A general theme of the workshop was that a strategy of controlling many pollutants with a single system rather than systems to control individual pollutants should be a research goal. Some research needs cited were: hazardous air pollutant removal by flue gas desulfurization systems, dioxin formation and control, mercury control, waste minimization, impact of ash recycling on metals partitioning, impact of urea and sorbents on other pollutants, high temperature filtration, impact of coal cleaning on metals partitioning, and modeling dispersion of sorbents in flue gas. information

  5. Design of engineered sorbent barriers

    International Nuclear Information System (INIS)

    Jones, E.O.; Freeman, H.D.

    1988-08-01

    A sorbent barrier uses sorbent material such as activated carbon or natural zeolites to prevent the migration of radionuclides from a low-level waste site to the aquifer. The sorbent barrier retards the movement of radioactive contaminants, thereby providing time for the radionuclides to decay. Sorbent barriers can be a simple, effective, and inexpensive method for reducing the migration of radionuclides to the environment. Designing a sorbent barrier consists of using soil and sorbent material properties and site conditions as input to a model which will determine the necessary sorbent barrier thickness to meet contaminant limits. The paper will cover the following areas: techniques for measuring sorption properties of barrier materials and underlying soils, use of a radionuclide transport model to determine the required barrier thickness and performance under a variety of site conditions, and cost estimates for applying the barrier. 8 refs., 6 figs., 1 tab

  6. Design of engineered sorbent barriers

    International Nuclear Information System (INIS)

    Jones, E.O.; Freeman, H.D.

    1988-01-01

    A sorbent barrier uses sorbent material such as activated carbon or natural zeolites to prevent the migration of radionuclides from a low-level waste site to the aquifer. The sorbent barrier retards the movement of radioactive contaminants, thereby providing time for the radionuclides to decay. Sorbent barriers can be a simple, effective, and inexpensive method for reducing the migration of radionuclides to the environment. Designing a sorbent barrier consists of using soil and sorbent material properties and site conditions as input to a model which will determine the necessary sorbent barrier thickness to meet contaminant limits. The paper covers the following areas: techniques for measuring sorption properties of barrier materials and underlying soils, use of a radionuclide transport model to determine the required barrier thickness and performance under a variety of site conditions, and cost estimates for applying the barrier

  7. Understanding the Federal Proposal Review Process.

    Science.gov (United States)

    Cavin, Janis I.

    Information on the peer review process for the evaluation of federal grant proposals is presented to help college grants administrators and faculty develop good proposals. This guidebook provides an overview of the policies and conventions that govern the review and selection of proposals for funding, and details the review procedures of the…

  8. Understanding the Role of Online Reviews on Customers' Risk Perception

    Science.gov (United States)

    Yang, Jing

    2013-01-01

    Customer reviews play an important role in today's online shopping environment. Research into customer reviews has largely focused on the predictive effect of review characteristics on variables such as product sales. However, relatively little attention has been directed towards understanding how reviews impact a customer's decision to purchase a…

  9. Review Essay: Understanding in Professional Interactions

    Directory of Open Access Journals (Sweden)

    Rainer Schützeichel

    2012-07-01

    Full Text Available "Professions" are work collaborations in which representatives of certain vocations address the life problems of "laypersons." In such relationships, adequate communication between representatives of the profession and laypersons is crucial in addressing their individual problems. Accordingly, "understanding," as well as interactional documentation of this understanding, is of considerable importance. The authors of the present volume, "Understanding in Professional Spheres of Activity,"  address the documentation of this understanding in certain professional spheres. They examine the requirements for the documentation of such understanding and the forms of documentation used in the fields of doctor-patient communication, counseling communication, and organizational collaboration on a movie set. Conversation analytic as well as ethnographically complemented studies draw further attention to an examination of the interactional level in its socio-structural context, and to that end the study employs a combination of conversational linguistics and sociological research. This contribution is therefore important not only in terms of linguistics but also sociologically. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1203142

  10. Understanding Peer Review of Scientific Research

    Science.gov (United States)

    Association of American Universities, 2011

    2011-01-01

    An important factor in the success of America's national research system is that federal funds for university-based research are awarded primarily through peer review, which uses panels of scientific experts, or "peers," to evaluate the quality of grant proposals. In this competitive process, proposals compete for resources based on their…

  11. Tutorial Review for Understanding of Cholangiopathy

    Directory of Open Access Journals (Sweden)

    Yasuni Nakanuma

    2012-01-01

    Full Text Available The biliary tree consists of intrahepatic and extrahepatic bile ducts and is lined by biliary epithelial cells (or cholangiocytes. There are also peribiliary glands around the intrahepatic large bile ducts and extrahepatic bile ducts. The biliary tree is a conduit of bile secreted by hepatocytes and biliary epithelial cells and also of the peribiliary glands and has several physiological roles. A number of diseases affect mainly the intrahepatic and extrahepatic biliary tree, and, in this special issue, these cholangiopathies are reviewed in detail with respect to genetics, pathogenesis, and pathology. In this paper, the anatomy and physiology of the biliary tree, basic injuries to biliary epithelial cells from stress and bile duct damage, and representative cholangiopathies are briefly reviewed.

  12. Understanding Kombucha Tea Fermentation: A Review.

    Science.gov (United States)

    Villarreal-Soto, Silvia Alejandra; Beaufort, Sandra; Bouajila, Jalloul; Souchard, Jean-Pierre; Taillandier, Patricia

    2018-03-01

    Kombucha is a beverage of probable Manchurian origins obtained from fermented tea by a microbial consortium composed of several bacteria and yeasts. This mixed consortium forms a powerful symbiosis capable of inhibiting the growth of potentially contaminating bacteria. The fermentation process also leads to the formation of a polymeric cellulose pellicle due to the activity of certain strains of Acetobacter sp. The tea fermentation process by the microbial consortium was able to show an increase in certain biological activities which have been already studied; however, little information is available on the characterization of its active components and their evolution during fermentation. Studies have also reported that the use of infusions from other plants may be a promising alternative. Kombucha is a traditional fermented tea whose consumption has increased in the recent years due to its multiple functional properties such as anti-inflammatory potential and antioxidant activity. The microbiological composition of this beverage is quite complex and still more research is needed in order to fully understand its behavior. This study comprises the chemical and microbiological composition of the tea and the main factors that may affect its production. © 2018 Institute of Food Technologists®.

  13. Peat hybrid sorbents for treatment of wastewaters and remediation of polluted environment

    Science.gov (United States)

    Klavins, Maris; Burlakovs, Juris; Robalds, Artis; Ansone-Bertina, Linda

    2015-04-01

    For remediation of soils and purification of polluted waters, wastewaters, sorbents might be considered as an prospective group of materials and amongst them peat have a special role due to low cost, biodegradability, high number of functional groups, well developed surface area and combination of hydrophilic/hydrophobic structural elements. Peat as sorbent have good application potential for removal of trace metals, and we have demonstrated peat sorption capacities, sorption kinetics, thermodynamics in respect to metals with different valencies - Tl(I), Cu(II), Cr(III). However peat sorption capacity in respect to nonmetallic (anionic species) elements is low. Also peat mechanical properties do not support application in large scale column processes. To expand peat application possibilities the approach of biomass based hybrid sorbents has been elaborated. The concept "hybrid sorbent" in our understanding means natural, biomass based sorbent modified, covered with another sorbent material, thus combining two types of sorbent properties, sorbent functionalities, surface properties etc. As the "covering layer" both inorganic substances, mineral phases (iron oxohydroxides, oxyapatite) both organic polymers (using graft polymerization) were used. The obtained sorbents were characterised by their spectral properties, surface area, elemental composition. The obtained hybrid sorbents were tested for sorption of compounds in anionic speciation forms, for example of arsenic, antimony, tellurium and phosphorous compounds in comparison with weakly basic anionites. The highest sorption capacity was observed when peat sorbents modified with iron compounds were used. Sorption of different arsenic speciation forms onto iron-modified peat sorbents was investigated as a function of pH and temperature. It was established that sorption capacity increases with a rise in temperature, and the calculation of sorption process thermodynamic parameters indicates the spontaneity of sorption

  14. Novel sorbents for environmental remediation

    Science.gov (United States)

    Manariotis, Ioannis D.; Karapanagioti, Hrissi K.; Werner, David

    2014-05-01

    Nowadays, one of the major environmental problems is the pollution of aquatic systems and soil by persistent pollutants. Persistent pollutants have been found widespread in sediments, surface waters, and drinking water supplies. The removal of pollutants can be accomplished prior to their discharge to receiving bodies or by immobilizing them onto soil. Sorption is the most commonly applied process, and activated carbons have been widely used. Rapid progress in nanotechnology and a new focus on biomass-based instead of non-renewable starting materials have produced a wide range of novel engineered sorbents including biosorbents, biochars, carbon-based nanoparticles, bio-nano hybrid materials, and iron-impregnated activated carbons. Sorbent materials have been used in environmental remediation processes and especially in agricultural soil, sediments and contaminated soil, water treatment, and industrial wastewater treatment. Furthermore, sorbents may enhance the synergistic action of other processes, such as volatilization and biodegradation. Novel sorbents have been employed for the removal or immobilization of persistent pollutants such as and include heavy metals (As, Cr, Cu, Pb, Cd, and Hg), halogenated organic compounds, endocrine disrupting chemicals, metalloids and non-metallic elements, and other organic pollutants. The development and evaluation of novel sorbents requires a multidisciplinary approach encompassing environmental, nanotechnology, physical, analytical, and surface chemistry. The necessary evaluations encompass not only the efficiency of these materials to remove pollutants from surface waters and groundwater, industrial wastewater, polluted soils and sediments, etc., but also the potential side-effects of their environmental applications. The aim of this work is to present the results of the use of biochar and impregnated carbon sorbents for the removal of organic pollutants and metals. Furthermore, the new findings from the forthcoming session

  15. Understanding low uptake of bone anchored hearing ads: A review.

    OpenAIRE

    Powell, Rachael; Wearden, Alison; Pardesi, Sophie M; Green, Kevin

    2017-01-01

    Background: Bone anchored hearing aids (Baha) improve hearing for patients for whom conventional behind-the-ear aids are problematic. However, uptake of Baha is low and it is important to understand why this is the case. Method: A narrative review was conducted. Studies examining why people accept or decline Baha and satisfaction in people with Baha were reviewed. Results: Reasons for declining Baha included limited perceived benefits, concerns about surgery, aesthetic concerns and treatment ...

  16. A Systematic Review of Current Understandings of Employability

    Science.gov (United States)

    Williams, Stella; Dodd, Lorna J.; Steele, Catherine; Randall, Raymond

    2016-01-01

    A theoretical framework is essential for the effective evaluation of employability. However, there are a wide range of definitions of employability coexisting in current literature. A review into existing ways in which employability has been conceptualised is needed to inform a better understanding of the nature of contributions made by various…

  17. Understanding Listening Competency: A Systematic Review of Research Scales

    Science.gov (United States)

    Fontana, Peter C.; Cohen, Steven D.; Wolvin, Andrew D.

    2015-01-01

    To better understand what constitutes listening competency, we perform a systematic review of listening scales. Our goal was twofold: to determine the most commonly appearing listening traits and to determine if listening scales are similar to one other. As part of our analysis, we identified 53 relevant scales and analyzed the scales…

  18. Sol-gel derived sorbents

    Science.gov (United States)

    Sigman, Michael E.; Dindal, Amy B.

    2003-11-11

    Described is a method for producing copolymerized sol-gel derived sorbent particles for the production of copolymerized sol-gel derived sorbent material. The method for producing copolymerized sol-gel derived sorbent particles comprises adding a basic solution to an aqueous metal alkoxide mixture for a pH.ltoreq.8 to hydrolyze the metal alkoxides. Then, allowing the mixture to react at room temperature for a precalculated period of time for the mixture to undergo an increased in viscosity to obtain a desired pore size and surface area. The copolymerized mixture is then added to an immiscible, nonpolar solvent that has been heated to a sufficient temperature wherein the copolymerized mixture forms a solid upon the addition. The solid is recovered from the mixture, and is ready for use in an active sampling trap or activated for use in a passive sampling trap.

  19. Literature Review of Applying Visual Method to Understand Mathematics

    Directory of Open Access Journals (Sweden)

    Yu Xiaojuan

    2015-01-01

    Full Text Available As a new method to understand mathematics, visualization offers a new way of understanding mathematical principles and phenomena via image thinking and geometric explanation. It aims to deepen the understanding of the nature of concepts or phenomena and enhance the cognitive ability of learners. This paper collates and summarizes the application of this visual method in the understanding of mathematics. It also makes a literature review of the existing research, especially with a visual demonstration of Euler’s formula, introduces the application of this method in solving relevant mathematical problems, and points out the differences and similarities between the visualization method and the numerical-graphic combination method, as well as matters needing attention for its application.

  20. A REVIEW ON “UNDERSTANDING PRAGMATICS BY JEF VERSCHUEREN”

    Directory of Open Access Journals (Sweden)

    Yasin KHOSHHAL

    2016-04-01

    Full Text Available Examining the mental and social processes involved in communication through language, Understanding Pragmatic is a comprehensive introduction to the subject. This book provides an overview of the theoretical basis of pragmatic, examines the main theoretical perspectives and explores its methodological aspects. As for the pragmatic in its broadest sense, covering the whole range of social, cultural and cognitive construction of meaning through the use of language aspects. Assuming no background in the pragmatic, the text provides helpful summaries, chapter by chapter for suggestions of reading and research topics for further study. The book tries to ad-dress questions such as what do people do when language is used? How exactly the meaning is generated when we communicate? And why do we say when we say something else? This review gives an overall review of the book and seeks to cover the whole concepts that are mentioned, eventually the reviewers have given their comment and conclusion of the book.

  1. Understanding medical symptoms: a conceptual review and analysis.

    Science.gov (United States)

    Malterud, Kirsti; Guassora, Ann Dorrit; Graungaard, Anette Hauskov; Reventlow, Susanne

    2015-12-01

    The aim of this article is to present a conceptual review and analysis of symptom understanding. Subjective bodily sensations occur abundantly in the normal population and dialogues about symptoms take place in a broad range of contexts, not only in the doctor's office. Our review of symptom understanding proceeds from an initial subliminal awareness by way of attribution of meaning and subsequent management, with and without professional involvement. We introduce theoretical perspectives from phenomenology, semiotics, social interactionism, and discourse analysis. Drew Leder's phenomenological perspectives deal with how symptom perception occurs when any kind of altered balance brings forward a bodily attention. Corporeality is brought to explicit awareness and perceived as sensations. Jesper Hoffmeyer's biosemiotic perspectives provide access to how signs are interpreted to attribute meaning to the bodily messages. Symptom management is then determined by the meaning of a symptom. Dorte E. Gannik's concept "situational disease" explains how situations can be reviewed not just in terms of their potential to produce signs or symptoms, but also in terms of their capacity to contain symptoms. Disease is a social and relational phenomenon of containment, and regulating the situation where the symptoms originate implies adjusting containment. Discourse analysis, as presented by Jonathan Potter and Margaret Wetherell, provides a tool to notice the subtle ways in which language orders perceptions and how language constructs social interaction. Symptoms are situated in culture and context, and trends in modern everyday life modify symptom understanding continuously. Our analysis suggests that a symptom can only be understood by attention to the social context in which the symptom emerges and the dialogue through which it is negotiated.

  2. Understanding attractiveness in business relationships - A complete literature review

    DEFF Research Database (Denmark)

    Mortensen, M. H.

    2012-01-01

    The concept of attraction has received surprisingly little attention within business relationship research. Yet, recently, more and more authors have argued that attraction may contribute to the motivation and willingness of a buyer and supplier to engage in and develop a business relationship...... or resolve a particular construct: 1) attraction in the development of buyer-supplier relationships, 2) customer attractiveness to suppliers, and 3) attractiveness in portfolio and key account management. This literature review contributes to the understanding of how knowledge of the power of attraction...

  3. High capacity carbon dioxide sorbent

    Science.gov (United States)

    Dietz, Steven Dean; Alptekin, Gokhan; Jayaraman, Ambalavanan

    2015-09-01

    The present invention provides a sorbent for the removal of carbon dioxide from gas streams, comprising: a CO.sub.2 capacity of at least 9 weight percent when measured at 22.degree. C. and 1 atmosphere; an H.sub.2O capacity of at most 15 weight percent when measured at 25.degree. C. and 1 atmosphere; and an isosteric heat of adsorption of from 5 to 8.5 kilocalories per mole of CO.sub.2. The invention also provides a carbon sorbent in a powder, a granular or a pellet form for the removal of carbon dioxide from gas streams, comprising: a carbon content of at least 90 weight percent; a nitrogen content of at least 1 weight percent; an oxygen content of at most 3 weight percent; a BET surface area from 50 to 2600 m.sup.2/g; and a DFT micropore volume from 0.04 to 0.8 cc/g.

  4. Decontamination formulation with sorbent additive

    Science.gov (United States)

    Tucker; Mark D. , Comstock; Robert H.

    2007-10-16

    A decontamination formulation and method of making that neutralizes the adverse health effects of both chemical and biological compounds, especially chemical warfare (CW) and biological warfare (BW) agents, and toxic industrial chemicals. The formulation provides solubilizing compounds that serve to effectively render the chemical and biological compounds, particularly CW and BW compounds, susceptible to attack, and at least one reactive compound that serves to attack (and detoxify or kill) the compound. The formulation includes at least one solubilizing agent, a reactive compound, a bleaching activator, a sorbent additive, and water. The highly adsorbent, water-soluble sorbent additive (e.g., sorbitol or mannitol) is used to "dry out" one or more liquid ingredients, such as the liquid bleaching activator (e.g., propylene glycol diacetate or glycerol diacetate) and convert the activator into a dry, free-flowing powder that has an extended shelf life, and is more convenient to handle and mix in the field.

  5. Evaluation of inorganic sorbent treatment for LWR coolant process streams

    International Nuclear Information System (INIS)

    Roddy, J.W.

    1984-03-01

    This report presents results of a survey of the literature and of experience at selected nuclear installations to provide information on the feasibility of replacing organic ion exchangers with inorganic sorbents at light-water-cooled nuclear power plants. Radioactive contents of the various streams in boiling water reactors and pressurized water reactors were examined. In addition, the methods and performances of current methods used for controlling water quality at these plants were evaluated. The study also includes a brief review of the physical and chemical properties of selected inorganic sorbents. Some attributes of inorganic sorbents would be useful in processing light water reactor (LWR) streams. The inorganic resins are highly resistant to damage from ionizing radiation, and their exchange capacities are generally equivalent to those of organic ion exchangers. However, they are more limited in application, and there are problems with physical integrity, especially in acidic solutions. Research is also needed in the areas of selectivity and anion removal before inorganic sorbents can be considered as replacements for the synthetic organic resins presently used in LWRs. 11 figures, 14 tables

  6. CaO-based CO2 sorbents: from fundamentals to the development of new, highly effective materials.

    Science.gov (United States)

    Kierzkowska, Agnieszka M; Pacciani, Roberta; Müller, Christoph R

    2013-07-01

    The enormous anthropogenic emission of the greenhouse gas CO2 is most likely the main reason for climate change. Considering the continuing and indeed growing utilisation of fossil fuels for electricity generation and transportation purposes, development and implementation of processes that avoid the associated emissions of CO2 are urgently needed. CO2 capture and storage, commonly termed CCS, would be a possible mid-term solution to reduce the emissions of CO2 into the atmosphere. However, the costs associated with the currently available CO2 capture technology, that is, amine scrubbing, are prohibitively high, thus making the development of new CO2 sorbents a highly important research challenge. Indeed, CaO, readily obtained through the calcination of naturally occurring limestone, has been proposed as an alternative CO2 sorbent that could substantially reduce the costs of CO2 capture. However, one of the major drawbacks of using CaO derived from natural sources is its rapidly decreasing CO2 uptake capacity with repeated carbonation-calcination reactions. Here, we review the current understanding of fundamental aspects of the cyclic carbonation-calcination reactions of CaO such as its reversibility and kinetics. Subsequently, recent attempts to develop synthetic, CaO-based sorbents that possess high and cyclically stable CO2 uptakes are presented. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Understanding plasma catalysis through modelling and simulation—a review

    International Nuclear Information System (INIS)

    Neyts, E C; Bogaerts, A

    2014-01-01

    Plasma catalysis holds great promise for environmental applications, provided that the process viability can be maximized in terms of energy efficiency and product selectivity. This requires a fundamental understanding of the various processes taking place and especially the mutual interactions between plasma and catalyst. In this review, we therefore first examine the various effects of the plasma on the catalyst and of the catalyst on the plasma that have been described in the literature. Most of these studies are purely experimental. The urgently needed fundamental understanding of the mechanisms underpinning plasma catalysis, however, may also be obtained through modelling and simulation. Therefore, we also provide here an overview of the modelling efforts that have been developed already, on both the atomistic and the macroscale, and we identify the data that can be obtained with these models to illustrate how modelling and simulation may contribute to this field. Last but not least, we also identify future modelling opportunities to obtain a more complete understanding of the various underlying plasma catalytic effects, which is needed to provide a comprehensive picture of plasma catalysis. (paper)

  8. A brief review: history to understand fundamentals of electrocardiography

    Directory of Open Access Journals (Sweden)

    Joseph Lindsay

    2012-04-01

    Full Text Available The last decade of the 19th century witnessed the rise of a new era in which physicians used technology along with classical history taking and physical examination for the diagnosis of heart disease. The introduction of chest x-rays and the electrocardiograph (electrocardiogram provided objective information about the structure and function of the heart. In the first half of the 20th century, a number of innovative individuals set in motion a fascinating sequence of discoveries and inventions that led to the 12-lead electrocardiogram, as we know it now. Electrocardiography, nowadays, is an essential part of the initial evaluation for patients presenting with cardiac complaints. As a first line diagnostic tool, health care providers at different levels of training and expertise frequently find it imperative to interpret electrocardiograms. It is likely that an understanding of the electrical basis of electrocardiograms would reduce the likelihood of error. An understanding of the disorders behind electrocardiographic phenomena could reduce the need for memorizing what may seem to be an endless list of patterns. In this article, we will review the important steps in the evolution of electrocardiogram. As is the case in most human endeavors, an understanding of history enables one to deal effectively with the present.

  9. Sorbent Nanotechnologies for Water Cleaning

    Science.gov (United States)

    Ahmed, Snober

    Despite decades of regulatory efforts to mitigate water pollution, many chemicals, particularly heavy metals, still present risks to human health. In addition to direct exposure, certain metals such as mercury threaten public health due to its persistence, bioaccumulation and bioamplification throughout the food chain. A number of U.S. Federal and State regulations have been established to reduce the levels of mercury in water. Activated carbon (AC) has been widely explored for the removal of mercury. However, AC suffers from many limitations inherent to its chemical properties, and it becomes increasingly challenging to meet current and future regulations by simply modifying AC to enhance its performance. Recently, the performance of nanosorbents have been studied in order to removal pollutants. Nanosorbents utilize the ultra-high reactive surface of nanoparticles for rapid, effective and even permanent sequestration of heavy metals from water and air, thus showed promising results as compared to AC. The goal of this thesis research is to develop nanomaterial-based sorbents for the removal of mercury from water. It describes the development of a new solid-support assisted growth of selenium nanoparticles, their use for water remediation, and the development of a new nanoselenium-based sorbent sponge for fast and efficient mercury removal. The nanoselenium sorbent not only shows irreversible interaction with mercury but also exhibits remarkable properties by overcoming the limitations of AC. The nanoselenium sponge was shown to remove mercury to undetectable levels within one minute. This new sponge technology would have an impact on inspiring new stringent regulations and lowering costs to help industries meet regulatory requirements, which will ultimately help improve air and water quality, aquatic life and public health.

  10. Sorbent Structural Impacts Due to Humidity on Carbon Dioxide Removal Sorbents for Advanced Exploration Systems

    Science.gov (United States)

    Watson, David; Knox, James C.; West, Phillip; Stanley, Christine M.; Bush, Richard

    2015-01-01

    The Life Support Systems Project (LSSP) under the Advanced Exploration Systems (AES) program builds upon the work performed under the AES Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project focusing on the numerous technology development areas. The CO2 removal and associated air drying development efforts are focused on improving the current state-of-the-art system on the International Space Station (ISS) utilizing fixed beds of sorbent pellets by seeking more robust pelletized sorbents, evaluating structured sorbents, and examining alternate bed configurations to improve system efficiency and reliability. A component of the CO2 removal effort encompasses structural stability testing of existing and emerging sorbents. Testing will be performed on dry sorbents and sorbents that have been conditioned to three humidity levels. This paper describes the sorbent structural stability screening efforts in support of the LSS Project within the AES Program.

  11. Final Project Report for DOE/EERE High-Capacity and Low-Cost Hydrogen-Storage Sorbents for Automotive Applications

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Hong-Cai [Texas A & M Univ., College Station, TX (United States); Liu, Di-Jia [Texas A & M Univ., College Station, TX (United States)

    2017-12-01

    This report provides a review of the objectives, progress, and milestones of the research conducted during this project on the topic of developing innovative metal-organic frameworks (MOFs) and porous organic polymers (POPs) for high-capacity and low-cost hydrogen-storage sorbents in automotive applications.1 The objectives of the proposed research were to develop new materials as next-generation hydrogen storage sorbents that meet or exceed DOE’s 2017 performance targets of gravimetric capacity of 0.055 kg H2/kgsystem and volumetric capacity of 0.040 kg H2/Lsystem at a cost of $400/kg H2 stored. Texas A&M University (TAMU) and Argonne National Laboratory (ANL) collaborated in developing low-cost and high-capacity hydrogen-storage sorbents with appropriate stability, sorption kinetics, and thermal conductivity. The research scope and methods developed to achieve the project’s goals include the following: Advanced ligand design and synthesis to construct MOF sorbents with optimal hydrogen storage capacities, low cost and high stability; Substantially improve the hydrogen uptake capacity and chemical stability of MOF-based sorbents by incorporating high valent metal ions during synthesis or through the post-synthetic metal metathesis oxidation approach; Enhance sorbent storage capacity through material engineering and characterization; Generate a better understanding of the H2-sorbent interaction through advanced characterization and simulation. Over the course of the project 5 different MOFs were developed and studied: PCN-250, PCN-12, PCN-12’, PCN-608 and PCN-609.2-3 Two different samples were submitted to the National Renewable Energy Laboratory (NREL) in order to validate their hydrogen adsorption capacity, PCN-250 and PCN-12. Neither of these samples reached the project’s Go/No-Go requirements but the data obtained did further prove the hypothesis that the presence of open metal

  12. Inorganic sorbents for radiostrontium removal from waste solutions: selectivity and role of calixarenes

    International Nuclear Information System (INIS)

    Vijayan, S.; Belikov, K.; Drapailo, A.

    2011-01-01

    The challenge in the remediation of 90 Sr-contaminated waters arises from the need to achieve very high removal efficiencies to meet discharge targets from waste effluents containing relatively high concentrations of non-radioactive cations. Low-cost natural zeolites are not selective for strontium over other divalent cations, notably such ions as calcium; and produce low 90 Sr removal performance, and large volumes of spent sorbent waste. The synthesis and use of selective, synthetic inorganic sorbents could prove to be a feasible approach for high 90 Sr removal efficiencies, and much smaller volumes of secondary solid waste generation. The essential advantages of inorganic sorbents include their stability and resistance to radiation, and the potential for producing stable waste forms such as vitrified glass or ceramics for disposal. However, the cost of strontium-specific sorbents is prohibitive for large-scale applications at present. This paper is a review of the reported information on removal mechanisms and performance of Sr-specific inorganic sorbents. The analysis has revealed promising performance, efficiency and selectivity for strontium removal from solutions containing low and high concentrations of salts. The leading sorbents are crystalline silicotitanate and oxides of metals such as titanium. An initial assessment has also been made of the performance of calixarene-based macrocyclic compounds. These are known for their selectivity for strontium in solvent extraction processes. From the initial strontium removal results in bench-scale tests using different solid substrates, impregnated with calixarene derivatives, only sodium-mordenite impregnated with calyx[8]arene octamide gave an overall strontium removal efficiency in the range of 90 to 95% in the presence of 3.5 ppm calcium. There was no improvement observed for strontium-removal efficiency or selectivity over calcium in the calixarene-impregnated inorganic sorbent matrix. In several tests, the

  13. Understanding Monitoring Technologies for Adults With Pain: Systematic Literature Review.

    Science.gov (United States)

    Rodríguez, Iyubanit; Herskovic, Valeria; Gerea, Carmen; Fuentes, Carolina; Rossel, Pedro O; Marques, Maíra; Campos, Mauricio

    2017-10-27

    Monitoring of patients may decrease treatment costs and improve quality of care. Pain is the most common health problem that people seek help for in hospitals. Therefore, monitoring patients with pain may have significant impact in improving treatment. Several studies have studied factors affecting pain; however, no previous study has reviewed the contextual information that a monitoring system may capture to characterize a patient's situation. The objective of this study was to conduct a systematic review to (1) determine what types of technologies have been used to monitor adults with pain, and (2) construct a model of the context information that may be used to implement apps and devices aimed at monitoring adults with pain. A literature search (2005-2015) was conducted in electronic databases pertaining to medical and computer science literature (PubMed, Science Direct, ACM Digital Library, and IEEE Xplore) using a defined search string. Article selection was done through a process of removing duplicates, analyzing title and abstract, and then reviewing the full text of the article. In the final analysis, 87 articles were included and 53 of them (61%) used technologies to collect contextual information. A total of 49 types of context information were found and a five-dimension (activity, identity, wellness, environment, physiological) model of context information to monitor adults with pain was proposed, expanding on a previous model. Most technological interfaces for pain monitoring were wearable, possibly because they can be used in more realistic contexts. Few studies focused on older adults, creating a relevant avenue of research on how to create devices for users that may have impaired cognitive skills or low digital literacy. The design of monitoring devices and interfaces for adults with pain must deal with the challenge of selecting relevant contextual information to understand the user's situation, and not overburdening or inconveniencing users with

  14. Peer review in design: Understanding the impact of collaboration on the review process and student perception

    Science.gov (United States)

    Mandala, Mahender Arjun

    A cornerstone of design and design education is frequent situated feedback. With increasing class sizes, and shrinking financial and human resources, providing rich feedback to students becomes increasingly difficult. In the field of writing, web-based peer review--the process of utilizing equal status learners within a class to provide feedback to each other on their work using networked computing systems--has been shown to be a reliable and valid source of feedback in addition to improving student learning. Designers communicate in myriad ways, using the many languages of design and combining visual and descriptive information. This complex discourse of design intent makes peer reviews by design students ambiguous and often not helpful to the receivers of this feedback. Furthermore, engaging students in the review process itself is often difficult. Teams can complement individual diversity and may assist novice designers collectively resolve complex task. However, teams often incur production losses and may be impacted by individual biases. In the current work, we look at utilizing a collaborative team of reviewers, working collectively and synchronously, in generating web based peer reviews in a sophomore engineering design class. Students participated in a cross-over design, conducting peer reviews as individuals and collaborative teams in parallel sequences. Raters coded the feedback generated on the basis of their appropriateness and accuracy. Self-report surveys and passive observation of teams conducting reviews captured student opinion on the process, its value, and the contrasting experience they had conducting team and individual reviews. We found team reviews generated better quality feedback in comparison to individual reviews. Furthermore, students preferred conducting reviews in teams, finding the process 'fun' and engaging. We observed several learning benefits of using collaboration in reviewing including improved understanding of the assessment

  15. Sorbents for the oxidation and removal of mercur

    Science.gov (United States)

    Olson, Edwin S.; Holmes, Michael J.; Pavlish, John Henry

    2017-09-12

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  16. Sorbents for the oxidation and removal of mercury

    Science.gov (United States)

    Olson, Edwin S [Grand Forks, ND; Holmes, Michael J [Thompson, ND; Pavlish, John H [East Grand Forks, MN

    2008-10-14

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  17. Sorbents for the oxidation and removal of mercury

    Science.gov (United States)

    Olson, Edwin S [Grand Forks, ND; Holmes, Michael J [Thompson, ND; Pavlish, John H [East Grand Forks, MN

    2012-05-01

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  18. Sorption of methylxanthines by different sorbents

    Science.gov (United States)

    Dmitrienko, S. G.; Andreeva, E. Yu.; Tolmacheva, V. V.; Terent'eva, E. A.

    2013-05-01

    Sorption of caffeine, theophylline, theobromine, diprophylline, and pentoxyphylline on different sorbents (supercross-linked polystyrene, surface-modified copolymer of styrene and divinylbenzene Strata-X, and carbon nanomaterials Taunit and Diasorb-100-C16T) was studied in a static mode in an effort to find new sorbents suitable for sorption isolation and concentration of methylxanthines. The peculiarities of sorption of methylxanthines were explained in relation to the solution acidity, the nature of the sorbates and their concentration, the nature of the solvent, and the structural characteristics of the sorbents.

  19. Ionic liquids: solvents and sorbents in sample preparation.

    Science.gov (United States)

    Clark, Kevin D; Emaus, Miranda N; Varona, Marcelino; Bowers, Ashley N; Anderson, Jared L

    2018-01-01

    The applications of ionic liquids (ILs) and IL-derived sorbents are rapidly expanding. By careful selection of the cation and anion components, the physicochemical properties of ILs can be altered to meet the requirements of specific applications. Reports of IL solvents possessing high selectivity for specific analytes are numerous and continue to motivate the development of new IL-based sample preparation methods that are faster, more selective, and environmentally benign compared to conventional organic solvents. The advantages of ILs have also been exploited in solid/polymer formats in which ordinarily nonspecific sorbents are functionalized with IL moieties in order to impart selectivity for an analyte or analyte class. Furthermore, new ILs that incorporate a paramagnetic component into the IL structure, known as magnetic ionic liquids (MILs), have emerged as useful solvents for bioanalytical applications. In this rapidly changing field, this Review focuses on the applications of ILs and IL-based sorbents in sample preparation with a special emphasis on liquid phase extraction techniques using ILs and MILs, IL-based solid-phase extraction, ILs in mass spectrometry, and biological applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Low-Cost Sorbents: A Literature Summary

    National Research Council Canada - National Science Library

    Bailey, Susan

    1997-01-01

    The capital and regeneration costs of activated carbon and ion exchange media suggest that better process economics may be achieved with disposable sorbents for the treatment of metals-contaminated...

  1. The use of clays as sorbents and catalysts

    International Nuclear Information System (INIS)

    McCabe, R.W.

    1998-01-01

    The paper attempts to show the structural, physical and chemical properties of clay minerals relate to their laboratory, industrial and environmental uses as sorbents and catalysts. A brief review of the formulae and structures of clays and their relationship to their chemical and physical properties follows. Clay minerals are also useful in environmental protection as they can adsorb crude oils from spills and they are used, sometimes mixed into concrete, as containment barriers for radionuclides caesium 137 and strontium 90. Clay soils can also act as natural barriers to the migration of radionuclides in the environment

  2. Application of engineered sorbent barriers Summary of Laboratory Data for FY 1988

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H.D.; Jones, E.O.

    1989-09-01

    Laboratory studies were conducted in FY 1988 Pacific Northwest Laboratory to determine the effect of contact time, pH, solution to solid ratio, and particle size on the performance of a number of materials in adsorbing radioactive cobalt, strontium, and cesium. The laboratory studies were conducted to provide background information useful in designing an engineered sorbent barrier, which restricts the migration of radionuclides from low-level waste sites. Understanding how the variables affect the adsorption of ions on the sorbent materials is the key to estimating the performance of sorbent barriers under a variety of conditions. The scope of the studies was limited to three radionuclides and four sorbent materials, but the general approach can be used to evaluate other radionuclides and conditions. The sorbent materials evaluated in this study included clinoptilolite, activated carbon, bentonite clay, and Savannah River soil. The clinoptilolite and activated carbon were identified in previous studies as the most cost-effective materials for sorption of the three radionuclides under consideration. The bentonite clay was evaluated as a component of the barrier that could be used to modify the permeability of the barrier system. The Savannah River soil was used to represent soil from a humid site. 3 refs., 14 figs., 1 tab.

  3. Application of inorganic sorbents for sewage purification from copper

    International Nuclear Information System (INIS)

    Yelizarova, I.A.; Tomchuk, T.K.; Kalinin, N.F.; Vol'khin, V.V.; Levichek, M.S.; Gulyaeva, E.I.

    1986-01-01

    Article presents the results of elaboration of synthesis methods of sorbent on the base of phosphate and magnesium hydroxide. As a result of study the technology of sorbent production with optimal properties was elaborated.

  4. Understanding Culture: A Literature Review Comparing Three Cultural Pedagogies

    OpenAIRE

    Tabitha Kidwell

    2017-01-01

    Culture is an integral part of language study, but the field has yet to put forward a coherent theoretical argument for how culture can or should be incorporated in language education.  In an effort to remedy this situation, this paper reviews literature on the teaching of culture, drawing on Larzén’s (2005) identification of three pedagogies used to teach about culture within the language classroom:  through a pedagogy of information, a pedagogy of preparation, and a pedagogy of encounter.  ...

  5. Long Life Moving-Bed Zinc Titanate Sorbent

    International Nuclear Information System (INIS)

    Copeland, Robert J.; Cesario, Mike; Feinberg, Daniel A.; Sibold, Jack; Windecker, Brian; Yang, Jing

    1997-01-01

    The objective of this work was to develop and test long-life sorbents for hot gas cleanup. Specifically, we measured the sulfur loading at space velocities typically used for absorption of H 2 S and regenerated the sorbent with diluted air for multiple cycles. Based on the experimental results, we prepared a conceptual design of the sorbent-fabrication system, and estimated the cost of sorbent production and of sulfur removal

  6. Strategic Design and Optimization of Inorganic Sorbents for Cesium, Strontium and Actinides

    International Nuclear Information System (INIS)

    Maginn, Edward J.

    2009-01-01

    The primary objective of the Notre Dame component of the project was computational in nature. The goal was to provide a design tool for the synthesis of optimized sorbents for the removal of cesium, strontium and actinides from nuclear waste solutions. Molecular modeling enables us to observe and better understand the molecular level interactions that govern the selectivity of specific radionuclides in a particular sorbent. The research focused on the development and validation of a suitable and transferable model for all the cations and ion exchangers of interest, nd then subsequent simulations which determined the siting and mobility of water and cations. Speciic accomplishments include: (1) improving existing intermolecular force fields to accurately model the sorbents of interest; (2) utilizing energy-minimizations and molecular dynamics simulations for structural prediction of CST and niobium-substituted CST materials; (3) determining Na+/water positions in polyoxoniobate materials using molecular dynamics simulations; and (4) developing Hybrid Monte Carlo methods for improved structural prediction.

  7. Separation of radionuclides from gas by sorption on activated charcoal and inorganic sorbents

    International Nuclear Information System (INIS)

    Kepak, F.

    1988-01-01

    The review deals with the sorption and ion exchange of gaseous radionuclides on activated charcoal and on inorganic sorbents. It presents the physical and chemical characteristics of radionuclides, the sources of gaseous forms of radionuclides as well as the composition of radioactive gases from some nuclear facilities. 79 refs. (author)

  8. UNDERSTANDING E-COMMERCE ADOPTION. LITERATURE REVIEW OF COMPETING MODELS

    Directory of Open Access Journals (Sweden)

    Constantin SASU

    2017-05-01

    Full Text Available The present paper reviews the theory of planned behaviour (Ajzen, 1991, the theory of reasoned action (Fishbein and Ajzen, 1975; Ajzen and Fishbein, 1980 and the theory of technology acceptance model (Davis, 1989 in order to better perceive their possible future application in the marketing field, namely in the process of using electronic commerce at the organizational level. While previous empirical studies have focused primarily on one of the theories, in an attempt to rule the advantages and / or disadvantages which would support the findings and hypothesis presented, it is the authors’ belief that all three theories greatly contribute, each one in a unique way. However, several pitfalls in methodology may be encountered, therefore further empirical research is required.

  9. Alkaline sorbent injection for mercury control

    Science.gov (United States)

    Madden, Deborah A.; Holmes, Michael J.

    2002-01-01

    A mercury removal system for removing mercury from combustion flue gases is provided in which alkaline sorbents at generally extremely low stoichiometric molar ratios of alkaline earth or an alkali metal to sulfur of less than 1.0 are injected into a power plant system at one or more locations to remove at least between about 40% and 60% of the mercury content from combustion flue gases. Small amounts of alkaline sorbents are injected into the flue gas stream at a relatively low rate. A particulate filter is used to remove mercury-containing particles downstream of each injection point used in the power plant system.

  10. Topical Report 5: Sorbent Performance Report

    Energy Technology Data Exchange (ETDEWEB)

    Krutka, Holly; Sjostrom, Sharon

    2011-05-31

    ADA-ES has completed an extensive sorbent screening program funded primarily through DOE NETL cooperative agreement DE-NT0005649 with support from EPRI and industry cost-share participants. Tests were completed on simulated and actual flue gas. The overall project objective is to address the viability and accelerate development of a solid-based postcombustion CO2 capture technology that can be retrofit to the existing fleet of coal-fired power plants. An important component of the viability assessment was to evaluate the state of development of sorbents and measure key performance characteristics under realistic operating conditions.

  11. Desulfurization Sorbents for Transport-Bed Applications

    International Nuclear Information System (INIS)

    Gupta, Raghubir P.; Turk, Brian S.; Vierheilig, Albert A.

    1997-01-01

    This project extends the prior work on the development of fluidizable zinc titanate particles using a spray-drying technique to impart high reactivity and attrition resistance. The specific objectives are: (1) To develop highly reactive and attrition-resistant zinc titanate sorbents in 40- to 150-(micro)m particle size range for transport reactor applications; (2) To transfer sorbent production technology to private sector; and (3) To provide technical support to Sierra Pacific Clean Coal Technology Demonstration plant and FETC's Hot-Gas Desulfurization Process Development Unit (PDU), both employing a transport reactor system

  12. Influence of lignin on properties of wood-inorganic sorbents

    International Nuclear Information System (INIS)

    Remez, V.P.; Charina, M.V.; Klass, S.M.; Shubin, A.S.; Tkachev, K.V.; Isaeva, O.F.

    1986-01-01

    Present article is devoted to influence of lignin on properties of wood-inorganic sorbents. The influence of component composition of matrix on sorption properties of sorbents and their stability in different mediums is studied. The dependence of sorption capacity of sorbent on component matrix composition and its porous structure is defined.

  13. Developing and understanding biofluid vibrational spectroscopy: a critical review.

    Science.gov (United States)

    Baker, Matthew J; Hussain, Shawn R; Lovergne, Lila; Untereiner, Valérie; Hughes, Caryn; Lukaszewski, Roman A; Thiéfin, Gérard; Sockalingum, Ganesh D

    2016-04-07

    Vibrational spectroscopy can provide rapid, label-free, and objective analysis for the clinical domain. Spectroscopic analysis of biofluids such as blood components (e.g. serum and plasma) and others in the proximity of the diseased tissue or cell (e.g. bile, urine, and sputum) offers non-invasive diagnostic/monitoring possibilities for future healthcare that are capable of rapid diagnosis of diseases via specific spectral markers or signatures. Biofluids offer an ideal diagnostic medium due to their ease and low cost of collection and daily use in clinical biology. Due to the low risk and invasiveness of their collection they are widely welcomed by patients as a diagnostic medium. This review underscores recent research within the field of biofluid spectroscopy and its use in myriad pathologies such as cancer and infectious diseases. It highlights current progresses, advents, and pitfalls within the field and discusses future spectroscopic clinical potentials for diagnostics. The requirements and issues surrounding clinical translation are also considered.

  14. Gulf War Syndrome: a review of current knowledge and understanding.

    Science.gov (United States)

    Minshall, D

    2014-01-01

    The 1991 Persian Gulf War was a resounding military success for coalition forces, who liberated Kuwait following the Iraqi invasion. The medical legacy we have from the conflict is the poorly understood, yet remarkable, phenomenon of Gulf War Syndrome, which surfaced soon after. Epidemiological research has proven beyond doubt that Gulf War veterans report a wide variety of symptoms, in excess of appropriately matched control subjects, and experience worse general health. Numerous toxic environmental hazards have been suggested as causes of Gulf War Syndrome, yet exhaustive scientific study has failed to provide conclusive proof of any link. No novel or recognised disease has been found to account for the symptomatic burden of veterans, and the optimal treatment remains uncertain. This understanding can be added to from an anthropological perspective, where the narratives of those afflicted provide further insight. The nature of military life was changing at the time of the Gulf War, challenging the identity and beliefs of some veterans and causing socio-cultural distress. The symptomatic presentation of Gulf War Syndrome can be considered an articulation of this disharmony. Gulf War Syndrome can also be considered within the group of post-combat disorders such as shellshock, the like of which have occurred after major wars in the last century. With the current withdrawal from Afghanistan, the Defence Medical Services (DMS) should heed the lessons of history.

  15. Non-carbon sorbents for mercury removal from flue gases

    Energy Technology Data Exchange (ETDEWEB)

    Alptekin, G.O.; Dubovik, M.; Cesario, M. [TDA Research Inc., Wheat Ridge, CO (United States)

    2005-07-01

    TDA Research Inc. is developing a new sorbent that can effectively remove mercury from flue gases. It is made of non-carbon based materials and will therefore not alter the properties of the fly ash. The sorbent can be produced as an injectable powder. The paper summarises the initial testing results of the new sorbent. The sorbent exhibited 7.5 to 11.0 mg/g mercury absorption capacity under representative flue gas streams depending on the operating temperature and gas hourly space velocity. The sorbent also showed resistance to sulfur poisoning by sulfur dioxide. 6 refs., 3 figs., 1 tab.

  16. Radon adsorption in fibrous carbon sorbents

    International Nuclear Information System (INIS)

    Anshakov, O.M.; Kish, A.O.; Chudakov, V.A.; Matvejchuk, S.V.; Sokolovskij, A.S.; Ugolev, I.I.

    2006-01-01

    Radon sorption in woven fibrous sorbents 'AUT-M' and 'Busofit' and nonwoven fiber in the temperature range 0-50 degrees centigrade was studied. Adsorption heat of radon from the ambient air in different types of carbon fiber was determined. (authors)

  17. Analysis of Ethane and Diethylbenzene Bridged Sorbents

    Science.gov (United States)

    2017-12-13

    Textiles modified in this manner have been shown to reduce or eliminate transport of chemical warfare agents and simulants across the fabric barrier...B.J. Johnson; B.J. Melde; M.H. Moore; A.P. Malanoski; J.R. Taft, "Improving sorbents for glycerol capture in biodiesel refinement," Materials 10

  18. BOOK REVIEW: New Understanding Physics for Advanced Level

    Science.gov (United States)

    Breithaupt, Jim

    2000-09-01

    Breithaupt's new book is big: at 727 pages, it will be a hefty addition to any student's bag. According to the preface, the book is designed to help students achieve the transition from GCSE to A-level and to succeed well at this level. It also aims to cover the requirements of the compulsory parts of all new syllabuses and to cover most of the optional material, too. The book is organized into seven themes along traditional lines: mechanics, materials, fields, waves, electricity, inside the atom, and physics in medicine. Each theme begins with a colourful title page that outlines what the theme is about, lists the applications that students will meet in their reading, identifies prior learning from GCSE and gives a checklist of what students should be able to do once they have finished their reading of the theme. This is all very useful. The text of the book is illustrated with many colourful photographs, pictures and cartoons, but despite this it looks very dense. There are a lot of words on every page in a small font that makes them seem very unfriendly, and although the book claims to be readable I rather doubt that the layout will encourage voluntary reading of the text. Each chapter ends with a useful summary and a selection of short questions that allow students to test their understanding. Each theme has a set of multiple choice and long questions. Some of the questions have an icon referring the student to the accompanying CD (more of this later). There is much up-to-date material in the book. For example, the section on cosmology gives a brief description of the inflationary scenario within the Big Bang model of the origin of the universe, although no mechanism for the inflation is given, which might prove unsatisfying to some students. I do have some reservations about the presentation of some topics within the book: the discussion of relativistic mass, for example, states that `Einstein showed that the mass ... is given by the formula ...' and quotes

  19. The antimicrobial efficiency of silver activated sorbents

    International Nuclear Information System (INIS)

    Đolić, Maja B.; Rajaković-Ognjanović, Vladana N.; Štrbac, Svetlana B.; Rakočević, Zlatko Lj.; Veljović, Đorđe N.; Dimitrijević, Suzana I.; Rajaković, Ljubinka V.

    2015-01-01

    Highlights: • Different sorbents were activated by Ag + -ions and modified sorbents were determined by sorption capacities, in range of values: 42.06–3.28 mg/g. • Granulated activated carbon (GAC), natural zeolit (Z) and titanium dioxide (T) activated by Ag + -ions were tested against E. coli, S. aureus and C. albicans. • The most successful bacteria removal was obtained using Ag/Z against S. aureus and E. coli, while the yeast cell reduction reached unsatisfactory effect for all three activated sorbents. • XRD, XPS and FE-SEM analysis showed that the chemical state of the silver activating agent affects the antimicrobial activity, as well as the structural properties of the material. • An overall microbial cell reduction, which is performed by separated antimicrobial tests on the Ag + -activated surface and Ag + -ions in aquatic solutions, is a consequence of both mechanisms. - Abstract: This study is focused on the surface modifications of the materials that are used for antimicrobial water treatment. Sorbents of different origin were activated by Ag + -ions. The selection of the most appropriate materials and the most effective activation agents was done according to the results of the sorption and desorption kinetic studies. Sorption capacities of selected sorbents: granulated activated carbon (GAC), zeolite (Z), and titanium dioxide (T), activated by Ag + -ions were following: 42.06, 13.51 and 17.53 mg/g, respectively. The antimicrobial activity of Ag/Z, Ag/GAC and Ag/T sorbents were tested against Gram-negative bacteria E. coli, Gram-positive bacteria S. aureus and yeast C. albicans. After 15 min of exposure period, the highest cell removal was obtained using Ag/Z against S. aureus and E. coli, 98.8 and 93.5%, respectively. Yeast cell inactivation was unsatisfactory for all three activated sorbents. The antimicrobial pathway of the activated sorbents has been examined by two separate tests – Ag + -ions desorbed from the activated surface to the

  20. The metal/water explosion phenomenon - a review of present understanding

    International Nuclear Information System (INIS)

    Vaughan, G.J.

    1980-05-01

    The metal/water explosion phenomenon has led to deaths and damage in several industrial incidents. This paper reviews the current understanding (up to 1978) of the phenomenon in terms of both the experimental evidence and the theoretical models that have been proposed. Complete understanding of the phenomenon has not been achieved and some recommendations are given for future work. (author)

  1. Sol-gel niobia sorbent with a positively charged octadecyl ligand providing enhanced enrichment of nucleotides and organophosphorus pesticides in capillary microextraction for online HPLC analysis.

    Science.gov (United States)

    Kesani, Sheshanka; Malik, Abdul

    2018-04-01

    A niobia-based sol-gel organic-inorganic hybrid sorbent carrying a positively charged C 18 ligand (Nb 2 O 5 -C 18 (+ve)) was synthesized to achieve enhanced enrichment capability in capillary microextraction of organophosphorus compounds (which include organophosphorus pesticides and nucleotides) before their online analysis by high-performance liquid chromatography. The sorbent was designed to simultaneously provide three different types of molecular level interactions: electrostatic, Lewis acid-base, and van der Waals interactions. To understand relative contributions of various molecular level analyte-sorbent interactions in the extraction process, two other sol-gel niobia sorbents were also created: (a) a purely inorganic sol-gel niobia sorbent (Nb 2 O 5 ) and (b) an organic-inorganic hybrid sol-gel niobia sorbent carrying an electrically neutral-bonded octadecyl ligand (Nb 2 O 5 -C 18 ). The extraction efficiency of the created sol-gel niobia sorbent (Nb 2 O 5 -C 18 (+ve)) was compared with that of analogously designed and synthesized titania-based sol-gel sorbent (TiO 2 -C 18 (+ve)), taking into consideration that titania-based sorbents present state-of-the-art extraction media for organophosphorus compounds. In capillary microextraction with high-performance liquid chromatography analysis, Nb 2 O 5 -C 18 (+ve) had shown 40-50% higher specific extraction values (a measure of extraction efficiency) over that of TiO 2 -C 18 (+ve). Compared to TiO 2 -C 18 (+ve), Nb 2 O 5 -C 18 (+ve) also provided superior analyte desorption efficiency (96 vs. 90%) during the online release of the extracted organophosphorus pesticides from the sorbent coating in the capillary microextraction capillary to the chromatographic column using reversed-phase high-performance liquid chromatography mobile phase. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Qualitative systematic reviews: their importance for our understanding of research relevant to pain.

    Science.gov (United States)

    Seers, Kate

    2015-02-01

    This article outlines what a qualitative systematic review is and explores what it can contribute to our understanding of pain. Many of us use evidence of effectiveness for various interventions when working with people in pain. A good systematic review can be invaluable in bringing together research evidence to help inform our practice and help us understand what works. In addition to evidence of effectiveness, understanding how people with pain experience both their pain and their care can help us when we are working with them to provide care that meets their needs. A rigorous qualitative systematic review can also uncover new understandings, often helping illuminate 'why' and can help build theory. Such a review can answer the question 'What is it like to have chronic pain?' This article presents the different stages of meta-ethnography, which is the most common methodology used for qualitative systematic reviews. It presents evidence from four meta-ethnographies relevant to pain to illustrate the types of findings that can emerge from this approach. It shows how new understandings may emerge and gives an example of chronic musculoskeletal pain being experienced as 'an adversarial struggle' across many aspects of the person's life. This article concludes that evidence from qualitative systematic reviews has its place alongside or integrated with evidence from more quantitative approaches.

  3. New polymer bounces into sorbent market

    International Nuclear Information System (INIS)

    Roy, K.A.

    1991-01-01

    Spectacular spills like the Exxon Valdez capture headlines and dominate conversation, but most releases involve quantities too small to attract media attention. For these spills, companies often rely on sorbents to collect the oil and dispose it. These devices come in a variety of shapes, sizes and absorbent materials, including a new generation of products that offers solid results-literally. This paper reports on the Solidifier which absorbs oil, as well as chlorinated solvents, hydrocarbons and PCBs, and, as the name implies, solidifies into a rubber-like material. A polymer used extensively in the rubber industry is the key to the sorbent's success. Oil and other contaminants, act like catalysts. They dissolve into the polymer, causing its molecules to bond together and form a rubber-like mass. No. 2 diesel fuel oil can be bounced on the floor after it solidifies

  4. Adsorption of Ammonia on Regenerable Carbon Sorbents

    Science.gov (United States)

    Wójtowicz, Marek A.; Cosgrove, Jesph E.; Serio, Michael A..; Wilburn, Monique

    2015-01-01

    Results are presented on the development of reversible sorbents for the combined carbon dioxide, moisture, and trace-contaminant (TC) removal for use in Extravehicular Activities (EVAs), and more specifically in the Primary Life Support System (PLSS). The currently available life support systems use separate units for carbon dioxide, trace contaminants, and moisture control, and the long-term objective is to replace the above three modules with a single one. Data on sorption and desorption of ammonia, which is a major TC of concern, are presented in this paper. The current TC-control technology involves the use of a packed bed of acid-impregnated granular charcoal, which is non-regenerable, and the carbon-based sorbent under development in this project can be regenerated by exposure to vacuum at room temperature. In this study, several carbon sorbents were fabricated and tested for ammonia sorption. Ammonia-sorption capacity was related to carbon pore structure characteristics, and the temperature of oxidative carbon-surface treatment was optimized for enhanced ammonia-sorption performance.

  5. Sorbents based on carbonized rice peel

    International Nuclear Information System (INIS)

    Mansurova, R. M.; Taipova, R. A.; Zhylybaeva, N. K.; Mansurov, Z. A.; Bijsenbaev, M. A.

    2004-01-01

    The process receiving of sorbents based on carbonized rice peel (RP) was received and their sorption properties were investigated. Processing carbonization of samples leading on station, this was developed in laboratory of hybrid technology. Carbonization of samples was realized in nitric atmosphere on 400-8000 deg. C. On raising temperature of carbonization content of carbon in samples is rice, hydrogen and oxygen is reduce as a result isolation of volatility products is discover. The samples carbonized on 650 deg. C (910 m 2 /g) owners with maximum removed surface is discover. On carbonization temperature 600-800 deh. C the sorption of ions, which carbonized by sorbents based on rice peel is run to 95-100 %. Electron-microscopic investigation of samples leaded on EM-125 mechanism by accelerating pressure 100 kV. From electron-microscopic print of original samples of RP it is evident, that sample consists of carbonic fractions of different species: carbonic fiber of rounded fractions, fractions of ellipsoid form and of more thickly carbonic structure. Increasing sizes of pores and modification structure of synthesized sorbent is occur during carbonization process. The RP-samples, which carbonized by 650 deg. C has the higher specific surface. Samples consist of thin carbonic scum and reducing specific surface, by higher temperature

  6. CO2 Capacity Sorbent Analysis Using Volumetric Measurement Approach

    Science.gov (United States)

    Huang, Roger; Richardson, Tra-My Justine; Belancik, Grace; Jan, Darrell; Knox, Jim

    2017-01-01

    In support of air revitalization system sorbent selection for future space missions, Ames Research Center (ARC) has performed CO2 capacity tests on various solid sorbents to complement structural strength tests conducted at Marshall Space Flight Center (MSFC). The materials of interest are: Grace Davison Grade 544 13X, Honeywell UOP APG III, LiLSX VSA-10, BASF 13X, and Grace Davison Grade 522 5A. CO2 capacity was for all sorbent materials using a Micromeritics ASAP 2020 Physisorption Volumetric Analysis machine to produce 0C, 10C, 25C, 50C, and 75C isotherms. These data are to be used for modeling data and to provide a basis for continued sorbent research. The volumetric analysis method proved to be effective in generating consistent and repeatable data for the 13X sorbents, but the method needs to be refined to tailor to different sorbents.

  7. Advanced sorbent development progam; development of sorbents for moving-bed and fluidized-bed applications

    International Nuclear Information System (INIS)

    Ayala, R.E.; Venkataramani, V.S.

    1998-01-01

    The integrated gasification combined cycle (IGCC) power system using high-temperature coal gas cleanup is one of the most promising advanced technologies for the production of electric power from coal in an environmentally acceptable manner. Unlike conventional low-temperature cleanup systems that require costly heat exchangers, high-temperature coal gas cleanup systems can be operated near 482-538 C (900-1000F) or higher, conditions that are a closer match with the gasifier and turbine components in the IGCC system, thus resulting is a more efficient overall system. GE is developing a moving-bed, high-temperature desulfurization system for the IGCC power cycle in which zinc-based regenerable sorbents are currently being used as desulfurization sorbents. Zinc titanate and other proprietary zinc-based oxides are being considered as sorbents for use in the Clean Coal Technology Demonstration Program at Tampa Electric Co.s (TECo) Polk Power Station. Under cold startup conditions at TECo, desulfurization and regeneration may be carried out at temperatures as low as 343 C (650 F), hence a versatile sorbent is desirable to perform over this wide temperature range. A key to success in the development of high-temperature desulfurization systems is the matching of sorbent properties for the selected process operating conditions, namely, sustainable desulfurization kinetics, high sulfur capacity, and mechanical durability over multiple cycles. Additionally, the sulfur species produced during regeneration of the sorbent must be in a form compatible with sulfur recovery systems, such as sulfuric acid or elemental sulfur processes. The overall objective of this program is to develop regenerable sorbents for hydrogen sulfide removal from coal-derived fuel gases in the temperature range 343-538 C (650-1000 F). Two categories of reactor configurations are being considered: moving-bed reactors and fluidized-bed (bubbling and circulating) reactors. In addition, a cost assessment and

  8. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  9. Properties and reactivity of reactivated calcium-based sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Davini, P. [Pisa University, Pisa (Italy). Dept. of Chemical Engineering

    2002-04-01

    Calcium-based sorbents used in the process of high temperature desulfurisation of flue gases are partly regenerable by hydration with steam; the best results are obtained for treatment temperatures of approximately 300{degree}C. The regeneration process, and the consequent increase in the sorbent consumption can be correlated to the surface characteristics (BET surface area, porosity and pore size distribution) of the sorbents themselves. In particular, the presence of suitable pore structure, also having pores large enough to let molecules easily penetrate the inner part of the sorbent particles, is very important. 27 refs., 9 figs., 2 tabs.

  10. Simple test guidelines for screening oilspill sorbents for toxicity

    International Nuclear Information System (INIS)

    Blenkinsopp, S.A.; Sergy, G.; Doe, K.; Jackman, P.; Huybers, A.

    1998-01-01

    Environment Canada's Emergencies Science Division has established a program to develop a standard test method suitable for evaluating the toxicity of common sorbent materials. Sorbents are used to absorb or adsorb spilled oil and other hazardous materials. They vary widely in composition and packaging. They are often treated with oleophilic and hydrophobic compounds to improve performance and have been used in large quantities during oil spills. Until now, their potential toxicity has never been considered. Three tests have been evaluated to determine how appropriate they are in screening the toxicity of sorbents. Seven toxicity test recommendations for sorbents were presented. 7 refs., 3 tabs., 2 figs

  11. Sorbent selection and design considerations for uranium trapping

    International Nuclear Information System (INIS)

    Schultz, R.M.; Hobbs, W.E.; Norton, J.L.; Stephenson, M.J.

    1981-07-01

    The efficient removal of UF 6 from effluent streams can be accomplished through the selection of the best solid sorbent and the implementation of good design principles. Pressure losses, sorbent capacity, reaction kinetics, sorbent regeneration/uranium recovery requirements and the effects of other system components are the performance factors which are summarized. The commonly used uranium trapping materials highlighted are sodium fluoride, H-151 alumina, XF-100 alumina, and F-1 alumina. Sorbent selection and trap design have to be made on a case-by-case basis but the theoretical modeling studies and the evaluation of the performance factors presented can be used as a guide for other chemical trap applications

  12. Informing people about radiation risks: a review of obstacles to public understanding and effective risk communication

    International Nuclear Information System (INIS)

    Covello, V.T.

    1988-01-01

    This paper reviews the literature on informing people about radiation risks. The paper focuses on obstacles to public understanding and effective risk communication. The paper concludes with a set of guidelines for communicating information about radiation risks to the public. The paper also includes an appendix that reviews the literature on one of the most important tools for communicating information about radiation risks: risk comparisons

  13. Anionic sorbents for arsenic and technetium species

    International Nuclear Information System (INIS)

    Lucero, Daniel A.; Moore, Robert Charles; Bontchev, Ranko Panayotov; Hasan, Ahmed Ali Mohamed; Zhao, Hongting; Salas, Fred Manuel; Holt, Kathleen Caroline

    2003-01-01

    Two sorbents, zirconium coated zeolite and magnesium hydroxide, were tested for their effectiveness in removing arsenic from Albuquerque municipal water. Results for the zirconium coated zeolite indicate that phosphate present in the water interfered with the sorption of arsenic. Additionally, there was a large quantity of iron and copper present in the water, corrosion products from the piping system, which may have interfered with the uptake of arsenic by the sorbent. Magnesium hydroxide has also been proven to be a strong sorbent for arsenic as well as other metals. Carbonate, present in water, has been shown to interfere with the sorption of arsenic by reacting with the magnesium hydroxide to form magnesium carbonate. The reaction mechanism was investigated by FT-IR and shows that hydrogen bonding between an oxygen on the arsenic species and a hydrogen on the Mg(OH)2 is most likely the mechanism of sorption. This was also confirmed by RAMAN spectroscopy and XRD. Technetium exists in multiple oxidation states (IV and VII) and is easily oxidized from the relatively insoluble Tc(IV) form to the highly water soluble and mobile Tc(VII) form. The two oxidation states exhibit different sorption characteristics. Tc(VII) does not sorb to most materials whereas Tc(IV) will strongly sorb to many materials. Therefore, it was determined that it is necessary to first reduce the Tc (using SnCl2) before sorption to stabilize Tc in the environment. Additionally, the effect of carbonate and phosphate on the sorption of technetium by hydroxyapatite was studied and indicated that both have a significant effect on reducing Tc sorption

  14. TRUEX process solvent cleanup with solid sorbents

    International Nuclear Information System (INIS)

    Tse, Pui-Kwan; Reichley-Yinger, L.; Vandegrift, G.F.

    1989-01-01

    Solid sorbents, alumina, silica gel, and Amberlyst A-26 have been tested for the cleanup of degraded TRUEX-NPH solvent. A sodium carbonate scrub alone does not completely remove acidic degradation products from highly degraded solvent and cannot restore the stripping performance of the solvent. By following the carbonate scrub with either neutral alumina or Amberlyst A-26 anion exchange resin, the performance of the TRUEX-NPH is substantially restored. The degraded TRUEX-NPH was characterized before and after treatment by supercritical fluid chromatography. Its performance was evaluated by americium distribution ratios, phase-separation times, and lauric acid distribution coefficients. 17 refs., 2 figs., 5 tabs

  15. Assessment of spent mushroom substrate as sorbent of fungicides: influence of sorbent and sorbate properties.

    Science.gov (United States)

    Marín-Benito, Jesús M; Rodríguez-Cruz, M Sonia; Andrades, M Soledad; Sánchez-Martín, María J

    2012-01-01

    The capacity of spent mushroom substrate (SMS) as a sorbent of fungicides was evaluated for its possible use in regulating pesticide mobility in the environment. The sorption studies involved four different SMS types in terms of nature and treatment and eight fungicides selected as representative compounds from different chemical groups. Nonlinear sorption isotherms were observed for all SMS-fungicide combinations. The highest sorption was obtained by composted SMS from Agaricus bisporus cultivation. A significant negative and positive correlation was obtained between the K(OC) sorption constants and the polarity index values of sorbents and the K(OW) of fungicides, respectively. The statistic revealed that more than 77% of the variability in the K(OW) could be explained considering these properties jointly. The other properties of both the sorbent (total carbon, dissolved organic carbon, or pH) and the sorbate (water solubility) were nonsignificant. The hysteresis values for cyprodinil (log K(OW)= 4) were for all the sorbents much higher (>3) than for other fungicides. This was consistent with the remaining sorption after desorption considered as an indicator of the sorption efficiency of SMS for fungicides. Changes in the absorption bands of fungicides sorbed by SMS observed by FTIR permitted establishing the interaction mechanism of fungicides with SMS. The findings of this work provide evidence for the potential capacity of SMS as a sorbent of fungicides and the low desorption observed especially for some fungicides, although they suggest that more stabilized or humified organic substrates should be produced to enhance their efficiency in environmental applications. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  16. Post-combustion carbon capture - solid sorbents and membranes

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, R.M.

    2009-01-15

    This report follows on from that on solvent scrubbing for post-combustion carbon capture from coal-fired power plants by considering the use of solid sorbents and membranes instead of solvents. First, mesoporous and microporous adsorbents are discussed: carbon-based adsorbents, zeolites, hydrotalcites and porous crystals. Attempts have been made to improve the performance of the porous adsorbent by functionalising them with nitrogen groups and specifically, amine groups to react with CO{sub 2} and thus enhance the physical adsorption properties. Dry, regenerable solid sorbents have attracted a good deal of research. Most of the work has been on the carbonation/calcination cycle of natural limestone but there have also been studies of other calcium-based sorbents and alkali metal-based sorbents. Membranes have also been studied as potential post-combustion capture devices. Finally, techno-economic studies predicting the economic performance of solid sorbents and membranes are discussed. 340 refs., 21 figs., 8 tabs.

  17. Detoxication and recycling of radioactive waters using selective mineral sorbents

    International Nuclear Information System (INIS)

    Berak, L.

    1980-01-01

    Activated BaSO 4 (designated AB 70) was proposed for use in decontaminating concentrated calcium salt solutions containing a small amount of 226 Ra. The AB 70 concentration factor amounts to 2x1a 3 . A sorption contactor for applying the powder sorbent was proposed and will be tested. The AB 70 sorbent liberates small amounts of sulphates into the decontaminated solution, and thus another suitable mineral sorbent was sought. A new sorbent could be synthetized and tested, called RAS-1 whose Ra/Ca selectivity is comparable to that of AB 70 while its Ra/Ba selectivity is considerably higher. The RAS-1 sorbent is also suitable for radiochemical separation in the analysis and concentration of Ra. (Ha)

  18. Using Recent BCI Literature to Deepen our Understanding of Clinical Neurofeedback: A Short Review.

    Science.gov (United States)

    Jeunet, Camille; Lotte, Fabien; Batail, Jean-Marie; Philip, Pierre; Micoulaud Franchi, Jean-Arthur

    2018-05-15

    In their recent paper, Alkoby et al. (2017) provide the readership with an extensive and very insightful review of the factors influencing NeuroFeedback (NF) performance. These factors are drawn from both the NF literature and the Brain-Computer Interface (BCI) literature. Our short review aims to complement Alkoby et al.'s review by reporting recent additions to the BCI literature. The object of this paper is to highlight this literature and discuss its potential relevance and usefulness to better understand the processes underlying NF and further improve the design of clinical trials assessing NF efficacy. Indeed, we are convinced that while NF and BCI are fundamentally different in many ways, both the BCI and NF communities could reach compelling achievements by building upon one another. By reviewing the recent BCI literature, we identified three types of factors that influence BCI performance: task-specific, cognitive/motivational and technology-acceptance-related factors. Since BCIs and NF share a common goal (i.e., learning to modulate specific neurophysiological patterns), similar cognitive and neurophysiological processes are likely to be involved during the training process. Thus, the literature on BCI training may help (1) to deepen our understanding of neurofeedback training processes and (2) to understand the variables that influence the clinical efficacy of NF. This may help to properly assess and/or control the influence of these variables during randomized controlled trials. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

  19. Workplace health understandings and processes in small businesses: a systematic review of the qualitative literature.

    Science.gov (United States)

    MacEachen, Ellen; Kosny, Agnieszka; Scott-Dixon, Krista; Facey, Marcia; Chambers, Lori; Breslin, Curtis; Kyle, Natasha; Irvin, Emma; Mahood, Quenby

    2010-06-01

    Small businesses (SBs) play an important role in global economies, employ half of all workers, and pose distinct workplace health problems. This systematic review of qualitative peer-reviewed literature was carried out to identify and synthesize research findings about how SB workplace parties understand and enact processes related to occupational health and safety (OHS). The review was conducted as part of a larger mixed-method review and in consultation with stakeholders. A comprehensive literature search identified 5067 studies. After screening for relevance, 20 qualitative articles were identified. Quality assessment led to 14 articles of sufficient quality to be included in the meta-ethnographic findings synthesis. This review finds that SBs have distinctive social relations of work, apprehensions of workplace risk, and legislative requirements. Eight themes were identified that consolidate knowledge on how SB workplace parties understand OHS hazards, how they manage risk and health problems, and how broader structures, policies and systems shape the practice of workplace health in SBs. The themes contribute to 'layers of evidence' that address SB work and health phenomena at the micro (e.g. employer or worker behavior), meso (e.g. organizational dynamics) and macro (e.g. state policy) levels. This synthesis details the unique qualities and conditions of SBs that merit particular attention from planners and occupational health policy makers. In particular, the informal workplace social relations can limit workers' and employers' apprehension of risk, and policy and complex contractual conditions in which SBs are often engaged (such as chains of subcontracting) can complicate occupational health responsibilities. This review questions the utility of SB exemptions from OHS regulations and suggests a legislative focus on the particular needs of SBs. It considers ways that workers might activate their own workplace health concerns, and suggests that more

  20. Sorbent-based Oxygen Production for Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sethi, Vijay [Western Research Inst. (WRI), Laramie, WY (United States)

    2017-01-31

    Project DE-FE0024075 deals with the development of a moderate-temperature sorbent-based oxygen production technology. Sorbent-based oxygen production process utilizes oxygen-storage properties of Perovskites to (1) adsorb oxygen from air in a solid sorbent, and (2) release the adsorbed oxygen into a sweep gas such as CO2 and/or steam for gasification systems or recycled flue gas for oxy-combustion systems. Pure oxygen can be produced by the use of vacuum instead of a sweep gas to affect the pressure swing. By developing more efficient and stable, higher sorption capacity, newer class of materials operating at moderate temperatures this process represents a major advancement in air separation technology. Newly developed perovskite ceramic sorbent materials with order-disorder transition have a higher O2 adsorption capacity, potentially 200 °C lower operating temperatures, and up to two orders of magnitude faster desorption rates than those used in earlier development efforts. The performance advancements afforded by the new materials lead to substantial savings in capital investment and operational costs. Cost of producing oxygen using sorbents could be as much as 26% lower than VPSA and about 13% lower than a large cryogenic air separation unit. Cost advantage against large cryogenic separation is limited because sorbent-based separation numbers up sorbent modules for achieving the larger capacity.

  1. Clinical Validity, Understandability, and Actionability of Online Cardiovascular Disease Risk Calculators: Systematic Review.

    Science.gov (United States)

    Bonner, Carissa; Fajardo, Michael Anthony; Hui, Samuel; Stubbs, Renee; Trevena, Lyndal

    2018-02-01

    Online health information is particularly important for cardiovascular disease (CVD) prevention, where lifestyle changes are recommended until risk becomes high enough to warrant pharmacological intervention. Online information is abundant, but the quality is often poor and many people do not have adequate health literacy to access, understand, and use it effectively. This project aimed to review and evaluate the suitability of online CVD risk calculators for use by low health literate consumers in terms of clinical validity, understandability, and actionability. This systematic review of public websites from August to November 2016 used evaluation of clinical validity based on a high-risk patient profile and assessment of understandability and actionability using Patient Education Material Evaluation Tool for Print Materials. A total of 67 unique webpages and 73 unique CVD risk calculators were identified. The same high-risk patient profile produced widely variable CVD risk estimates, ranging from as little as 3% to as high as a 43% risk of a CVD event over the next 10 years. One-quarter (25%) of risk calculators did not specify what model these estimates were based on. The most common clinical model was Framingham (44%), and most calculators (77%) provided a 10-year CVD risk estimate. The calculators scored moderately on understandability (mean score 64%) and poorly on actionability (mean score 19%). The absolute percentage risk was stated in most (but not all) calculators (79%), and only 18% included graphical formats consistent with recommended risk communication guidelines. There is a plethora of online CVD risk calculators available, but they are not readily understandable and their actionability is poor. Entering the same clinical information produces widely varying results with little explanation. Developers need to address actionability as well as clinical validity and understandability to improve usefulness to consumers with low health literacy.

  2. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Berggren, M.H.; Jha, M.C.

    1989-10-01

    AMAX Research Development Center (AMAX R D) investigated methods for enhancing the reactivity and durability of zinc ferrite desulfurization sorbents. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For this program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and oxidation. Two base case sorbents, a spherical pellet and a cylindrical extrude used in related METC-sponsored projects, were used to provide a basis for the aimed enhancement in durability and reactivity. Sorbent performance was judged on the basis of physical properties, single particle kinetic studies based on thermogravimetric (TGA) techniques, and multicycle bench-scale testing of sorbents. A sorbent grading system was utilized to quantify the characteristics of the new sorbents prepared during the program. Significant enhancements in both reactivity and durability were achieved for the spherical pellet shape over the base case formulation. Overall improvements to reactivity and durability were also made to the cylindrical extrude shape. The primary variables which were investigated during the program included iron oxide type, zinc oxide:iron oxide ratio, inorganic binder concentration, organic binder concentration, and induration conditions. The effects of some variables were small or inconclusive. Based on TGA studies and bench-scale tests, induration conditions were found to be very significant.

  3. NIFSIL - a composite sorbent for caesium - properties and application

    International Nuclear Information System (INIS)

    Rajec, P.; Orechovska, J.

    1998-01-01

    Samples of the potassium-nickel ferrocyanides K 2 NiFe(CN) 6 , KNi 1,5 Fe(CN) 6 and Ni 2 Fe(CN) 6 were prepared and their properties studied with respect to their use as sorbents for caesium. Caesium is fixed on mixed alkaline-nickel ferrocyanide without structural change. The capacity of Cs retention never reached the theoretic value corresponding to a total release of the monovalent ions of the solid. High distribution coefficients (K D in the order of 10 4 cm 3 /g) determined in batch experiments show that these sorbents have a very high affinity for caesium ions, even in the presence of competing K + , Na + and Ca 2+ ions. The sorbents have a good chemical stability in a wide pH-range (2-12). The irradiation of some sorbent samples with high energy gamma-rays ( 60 Co) of a total dose of 1.10 5 Gy caused no remarkable changes in the sorbent properties (K D , sorption capacity and kinetics, mechanical stability). The sorbents were also tested for 85 Sr and 239 Pu and the results carried out under dynamic and batch experiments have shown that sorbents are not suitable for removal of these radionuclides. Potassium nickel hexacyanoferrate incorporated in silica-gel matrix could compete with others sorbents based on insoluble hexacyanoferrates, has the advantage of good radiation stability and suitable granulometry. The sorbent was prepared on a pilot scale with a capacity about 1000 kg per year with the prospect that it could be easily upgraded to an industrial scale

  4. Octahedral molecular sieve sorbents and catalysts

    Science.gov (United States)

    Li, Liyu [Richland, WA; King, David L [Richland, WA

    2010-04-20

    Octahedral molecular sieve sorbents and catalysts are disclosed, including silver hollandite and cryptomelane. These materials can be used, for example, to catalyze the oxidation of CO.sub.x (e.g., CO), NO.sub.x (e.g., NO), hydrocarbons (e.g., C.sub.3H.sub.6) and/or sulfur-containing compounds. The disclosed materials also may be used to catalyze other reactions, such as the reduction of NO.sub.2. In some cases, the disclosed materials are capable of sorbing certain products from the reactions they catalyze. Silver hollandite, in particular, can be used to remove a substantial portion of certain sulfur-containing compounds from a gas or liquid by catalysis and/or sorption. The gas or liquid can be, for example, natural gas or a liquid hydrocarbon.

  5. Potential of Cogon Grass as an Oil Sorbent

    OpenAIRE

    Wiloso, Edi Iswanto; Barlianti, Vera; Anggraini, Irni Fitria; Hendarsyah, Hendris

    2012-01-01

    Experiments on the potential of Cogon grass (lmperata cylindrica), a weed harmful to other plants, for use as a low-cost and biodegradable oil sorbent were carried out under various spill conditions. Flowers of Cogon grass adsorbed much larger amount of high-viscosity lubricating oil (57.9 g-oil/g-sorbent) than that adsorbed by Peat Sorb (7.7 g-oil/g-sorbent), a commercial oilsorbent based on peat. However, the flowers adsorbed only 27.9 g of low-viscosity crude oillgsorbent. In an oil-water ...

  6. Understanding asexual identity as a means to facilitate culturally competent care: A systematic literature review.

    Science.gov (United States)

    Jones, Catriona; Hayter, Mark; Jomeen, Julie

    2017-12-01

    To provide a contemporary overview of asexuality and the implications this has for healthcare practice. Individuals belonging to sexual minority groups face many barriers in accessing appropriate health care. The term "sexual minority group" is usually used to refer to lesbian women, gay, bisexual and transgender individuals. Anecdotal and research evidence suggests that those who identify as asexual have similar poor experiences. Systematic review and qualitative analysis. This work uses a systematic review and qualitative analysis of the existing interview data from self-identified asexuals, to construct features of the asexual identity. The findings will help practitioners and health professionals develop an understanding of this poorly understood construct. Ultimately this work is aimed at facilitating culturally competent care in the context of asexuality. Qualitative analysis produced three themes, which can be used, not only to frame asexuality in a positive and normalising way, but also to provide greater understanding of asexuality, "romantic differences coupled with sexual indifference," "validation through engagement with asexual communities" and "a diversity of subasexual identities." Having some understanding of what it means to identify as asexual, and respecting the choices made by asexuals can markedly improve the experiences of those who embrace an asexual identity when engaging with health care. Anecdotal evidence, taken from one of the largest asexual online forums, suggests that a number of self-identified asexuals choose not to disclose their identity to healthcare professionals through fear of their asexual status being pathologised, problematised or judged. Given that asexuality is a poorly understood concept, this may be due to lack of understanding on behalf of healthcare providers. The review provides health professionals and practitioners working in clinical settings with some insights of the features of an asexual identity to facilitate

  7. Biochar from Coffee Residues: A New Promising Sorbent

    Science.gov (United States)

    Fotopoulou, Kalliopi; Karapanagioti, Hrissi; Manariotis, Ioannis

    2014-05-01

    Biochar is a carbon-rich material produced by heating biomass in an oxygen-limited environment. Biochar is mainly used as an additive to soils to sequester carbon and improve soil fertility as well as a sorbent for environmental remediation processes. Surface properties such as point of zero charge, surface area and pore volume, surface topography, surface functional groups and acid-base behavior are important factors, which affect sorption efficiency. Understanding the surface alteration of biochars increases our understanding of the pollutant-sorbent interaction. The objective of the present study was to characterize the surface properties of biochar produced, and to investigate the effect of thermal treatment conditions on key characteristics that affect sorptive properties. The espresso coffee residue was obtained after the coffee was brewed through espresso machines in coffee shops. The coffee residue was dried and kept in an oven at 50oC until its pyrolysis at 850oC. Pyrolysis with different coffee mass and containers were tested in order to find optimum biochar characteristics. Detailed characterization techniques were carried out to determine the properties of the produced biochar. The surface area, the pore volume, and the average pore size of the biochars were determined using gas (N2) adsorption-desorption cycles using the Brunauer, Emmett, and Teller (BET) equation. Open surface area and micropore volume were determined using the t-plot method and the Harkins & Jura equation. Total organic carbon was also determined because it is an important factor that affects sorption. The results were compared with the corresponding properties of activated carbons. The biochar produced exhibited a wide range of surface area from 21 to 770 m2/g and open surface area from 21 to 65 m2/g. It is obvious that the surface area results from the formation of pores. Actually it was calculated that up to 90% of the porosity is due to the micropores. More specifically the

  8. The role of graphene-based sorbents in modern sample preparation techniques.

    Science.gov (United States)

    de Toffoli, Ana Lúcia; Maciel, Edvaldo Vasconcelos Soares; Fumes, Bruno Henrique; Lanças, Fernando Mauro

    2018-01-01

    The application of graphene-based sorbents in sample preparation techniques has increased significantly since 2011. These materials have good physicochemical properties to be used as sorbent and have shown excellent results in different sample preparation techniques. Graphene and its precursor graphene oxide have been considered to be good candidates to improve the extraction and concentration of different classes of target compounds (e.g., parabens, polycyclic aromatic hydrocarbon, pyrethroids, triazines, and so on) present in complex matrices. Its applications have been employed during the analysis of different matrices (e.g., environmental, biological and food). In this review, we highlight the most important characteristics of graphene-based material, their properties, synthesis routes, and the most important applications in both off-line and on-line sample preparation techniques. The discussion of the off-line approaches includes methods derived from conventional solid-phase extraction focusing on the miniaturized magnetic and dispersive modes. The modes of microextraction techniques called stir bar sorptive extraction, solid phase microextraction, and microextraction by packed sorbent are discussed. The on-line approaches focus on the use of graphene-based material mainly in on-line solid phase extraction, its variation called in-tube solid-phase microextraction, and on-line microdialysis systems. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Mechanochemically Activated, Calcium Oxide-Based, Magnesium Oxide-Stabilized Carbon Dioxide Sorbents.

    Science.gov (United States)

    Kurlov, Alexey; Broda, Marcin; Hosseini, Davood; Mitchell, Sharon J; Pérez-Ramírez, Javier; Müller, Christoph R

    2016-09-08

    Carbon dioxide capture and storage (CCS) is a promising approach to reduce anthropogenic CO2 emissions and mitigate climate change. However, the costs associated with the capture of CO2 using the currently available technology, that is, amine scrubbing, are considered prohibitive. In this context, the so-called calcium looping process, which relies on the reversible carbonation of CaO, is an attractive alternative. The main disadvantage of naturally occurring CaO-based CO2 sorbents, such as limestone, is their rapid deactivation caused by thermal sintering. Here, we report a scalable route based on wet mechanochemical activation to prepare MgO-stabilized, CaO-based CO2 sorbents. We optimized the synthesis conditions through a fundamental understanding of the underlying stabilization mechanism, and the quantity of MgO required to stabilize CaO could be reduced to as little as 15 wt %. This allowed the preparation of CO2 sorbents that exceed the CO2 uptake of the reference limestone by 200 %. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Evaluation of 137Cs sorbents for fixation in concrete

    International Nuclear Information System (INIS)

    Plodinec, M.J.

    1976-01-01

    As part of the long-term waste management program at the Savannah River Laboratory, several 137 Cs sorbents were evaluated for incorporation into concrete. The sorbents studied were: Linde AW-300, AW-500, 13-X, and SK-40; Norton Zeolon 200, 500, and 900; clinoptilolite; and vermiculite. The parameters studied were sorption kinetics, leachability, and compressive strength of the concrete. The best sorbents identified were Linde AW-500 and Norton Zeolon 900. In all tests, these two sorbents performed almost identically; sorption kinetics were acceptable; both strengthened the concrete, and both gave relatively leach-resistant concrete. Vermiculite that had been heated to collapse its lattice around 137 Cs gave the most leach-resistant concrete. However, it sorbed cesium slowly, and the resulting concrete was very weak. When silica gel was added to concrete to react with free calcium, the addition had no effect on cesium leachability

  11. Novel Sorbent to Clean Up Biogas for CHPs

    Energy Technology Data Exchange (ETDEWEB)

    Alptekin, Gökhan O. [TDA Research, Incorporated, Wheat Ridge, CO (United States); Jayataman, Ambalavanan [TDA Research, Incorporated, Wheat Ridge, CO (United States); Schaefer, Matthew [TDA Research, Incorporated, Wheat Ridge, CO (United States); Ware, Michael [TDA Research, Incorporated, Wheat Ridge, CO (United States); Hunt, Jennifer [FuelCell Energy, Inc., Danbury, CT (United States); Dobek, Frank [FuelCell Energy, Inc., Danbury, CT (United States)

    2015-05-30

    In this project, TDA Research Inc. (TDA) has developed low-cost (on a per unit volume of gas processed basis), high-capacity expendable sorbents that can remove both the H2S and organic sulfur species in biogas to the ppb levels. The proposed sorbents will operate downstream of a bulk desulfurization system as a polishing bed to provide an essentially sulfur-free gas to a fuel cell (or any other application that needs a completely sulfur-free feed). Our sorbents use a highly dispersed mixed metal oxides active phase with desired modifiers prepared over on a mesoporous support. The support structure allows the large organic sulfur compounds (such as the diethyl sulfide and dipropyl sulfide phases with a large kinetic diameter) to enter the sorbent pores so that they can be adsorbed and removed from the gas stream.

  12. Dual layer hollow fiber sorbents: Concept, fabrication and characterization

    KAUST Repository

    Bhandari, Dhaval; Olanrewaju, Kayode O.; Bessho, Naoki; Breedveld, Victor; Koros, William J.

    2013-01-01

    and to ensure consistent sorption capacity over repeated cycles, a dense, thin polymer barrier layer on the fiber sorbents is needed to allow only thermal interactions between the sorbate loaded layer and the thermal regeneration fluid. This paper considers

  13. Developing mathematics edutainment media for Android based on students’ understanding and interest: a teachers’ review

    Science.gov (United States)

    Setyaningrum, W.; Waryanto, N. H.

    2018-03-01

    This paper aimed to describe the development of interactive edutainment mathematics media using Construct 2 software for grade 7 Junior High School, and to determine the quality of the interactive edutainment media developed in regards to improve students’ understanding and interest. This research employs Research and Development design, which media was developed using ADDIE model consisting of analysing, designing, developing, implementing and evaluating. This paper focuses on the steps of development and validity of the interactive media from teachers’ point of view. The teachers review focuses on three aspects – instructional, audio-visual and operational design. The review suggested that the media was very good in regard to the three aspects, with the average score was 144.55 from the maximum score of 175. Several contexts used in the game, however, need to be adjusted to students age.

  14. A review of consumer awareness, understanding and use of food based dietary guidelines

    DEFF Research Database (Denmark)

    Brown, Kerry; Timotijevic, Lada; Barnett, Julie

    2011-01-01

    discussed interchangeably. Nevertheless, a greater amount of evidence for consumer awareness and understanding was reported than consumer use of FBDG. The twenty-eight studies varied in terms of aim, design and method. Study quality also varied with raw qualitative data, and quantitative method details were......Food-based dietary guidelines (FBDG) have primarily been designed for the consumer to encourage healthy, habitual food choices, decrease chronic disease risk and improve public health. However, minimal research has been conducted to evaluate whether FBDG are utilised by the public. The present...... review used a framework of three concepts, awareness, understanding and use, to summarise consumer evidence related to national FBDG and food guides. Searches of nine electronic databases, reference lists and Internet grey literature elicited 939 articles. Predetermined exclusion criteria selected twenty...

  15. Water purification from radionuclides with using fibroid sorbents

    International Nuclear Information System (INIS)

    Khaydarov, R. A.; Gapurova, O.U.; Khaydarov, R.R.

    2005-01-01

    Full text: Purification waste water and drinking water from radionuclides, heavy metal ions, organic contamination is one of the important problems today. For solving this problem we have created three types of fibroid sorbents on the base of Polyester: cationic and anionic exchange and carbonic. Main properties of these sorbents are described in this article. For example characteristics of the sorbents for removing radionuclides Co-60,57, Zn-65, Sr-89,90, Cs-134,137, etc., radionuclides containing organic molecules M-P-32, M-I-131, M-Mo-99+Tc-99m, M-C-14, etc., heavy metal ions Zn, Ni, Cu, Sb, Pb, Cd, Cr, U, etc., organic molecules (pesticides, phenols, dioxin, benzene, toluene, etc.) were investigated. Influence of pH on percent removal, influence of K, Na and another ions concentrations in the liquid on the percent removal, decreasing of the saturation capacity from number of regeneration and another characteristics are described. Static exchange capacity of the cationic sorbents is 1-2 mg-equ/g and anionic - 0.5-1 mg-equ/g. Capacity of the carbonic sorbents for benzene is 100 mg/g. Time of chemical balance setting is 1-2 s. The sorbents are effective in removing the low concentrations of contamination from the water (lower than 100-200 mg/l) and the air (lower than 100 mg/m 3 ). The use of sorbents in drinking water filters and mini-systems is described. The industrial water purification system consists of coagulating unit, sorbent unit and disinfectant unit. The systems are used in atomic power stations, electroplating plants, matches plants, leather and skin treating plants, car-washing stations, etc

  16. REMOVAL OF ANIONIC SURFACTANTS FROM WASTEWATER BY MAGNETIC MINERAL SORBENTS

    Directory of Open Access Journals (Sweden)

    Oksana Vladimirova Makarchuk

    2016-07-01

    Full Text Available The simplest and most effective method of removing low concentrations of anionic surfactants such as sodium dodecyl benzenesulfonate (SDBS and sodium lauryl sulfate (SLS is adsorption. Among adsorbents the natural clays are cheap and promising for these purposes. However, there are significant difficulties in removal of spent sorbent after the adsorption process. So, the creation of magnetic sorbents that can be effectively removed from water after sorption by magnetic separation will be a successful decision. The aim of this investigation is the creation of cheap and efficient magnetic sorbents based on natural clays and magnetite for anionic surfactant removal from wastewater. We have synthesized a series of magnetic sorbents from different natural clays with a content of magnetite from 2 to 10 wt%. The ability of magnetic sorbents to remove SDBS and SLS from aqueous solutions has been studied for different adsorbate concentrations by varying the amount of adsorbent, temperature and shaking time. Thermodynamic parameters were calculated from the slope and intercept of the linear plots of ln K against 1/T. Analysis of adsorption results obtained at different temperatures showed that the adsorption pattern on magnetic sorbents correspond to the Langmuir isotherm. It is shown that with increasing the content of magnetite in the magnetic sorbents improves not only their separation from water by magnetic separation, but adsorption capacity to SDBS and SLS. Thus, we obtained of cheap magnetic sorbents based on natural clays and magnetite by the easy way, which not only quickly separated from the solution by magnetic separation, but effectively remove anionic surfactants.

  17. Effectiveness of liquid radioactive waste purification by inorganic granulated sorbents

    International Nuclear Information System (INIS)

    Komarevskij, V.M.; Stepanets, O.V.; Sharygin, L.M.; Matveev, S.A.

    1995-01-01

    Study results on purification of simulative and real liquid radioactive wastes from fission products radionuclides and by inorganic corrosion-nature sorbents 'Thermoxide' are presented. Properties by sorption of cesium, strontium and cobalt are studied; results of experiments on purification of weakly-salted water solutions (waste waters, ships drainage tanks, showers and laundries) of the Beloyarsk NPP are presented. Sorbents source characteristics are determined. 4 refs., 2 figs., 3 tabs

  18. Engineered sorbent barriers for low-level waste disposal

    International Nuclear Information System (INIS)

    Mitchell, S.J.; Freeman, H.D.; Buelt, J.L.

    1987-01-01

    The Engineered Sorbent Barriers Program at Pacific Northwest Laboratory is developing sorbent materials to prevent the migration of radionuclides from low-level waste sites. These materials would allow water to pass, preventing the bathtub effect at humid sites. Screening studies identified promising sorbent materials for three key radionuclides: for cesium, greensand; for cobalt, activated charcoal; and for strontium, synthetic zeolite of clinoptilolite. Mixtures of these sorbent materials were tested in 0.6-m-diameter columns using radioactive leachates. To simulate expected worst-case conditions, the leachate solution contained the radionuclides, competing cations, and a chelating agent, adjusted to a pH of 5. A sorbent barrier comprised of greensand (1 wt%), activated charcoal (6 wt%), synthetic zeolite (20 wt%), and soil (73 wt%) achieved the decontamination factors necessary to meet the regulatory performance requirements established for this study. Sorbent barriers can be applied to shallow land burial, as backfill around the waste or engineered structures, or as backup to other liner systems. 2 references, 6 figures, 3 tables

  19. Characterization of calcium carbonate sorbent particle in furnace environment

    International Nuclear Information System (INIS)

    Lee, Kang Soo; Jung, Jae Hee; Keel, Sang In; Yun, Jin Han; Min, Tai Jin; Kim, Sang Soo

    2012-01-01

    The oxy-fuel combustion system is a promising technology to control CO 2 and NO X emissions. Furthermore, sulfation reaction mechanism under CO 2 -rich atmospheric condition in a furnace may lead to in-furnace desulfurization. In the present study, we evaluated characteristics of calcium carbonate (CaCO 3 ) sorbent particles under different atmospheric conditions. To examine the physical/chemical characteristics of CaCO 3 , which is used as a sorbent particle for in-furnace desulfurization in the oxy-fuel combustion system, they were injected into high temperature drop tube furnace (DTF). Experiments were conducted at varying temperatures, residence times, and atmospheric conditions in a reactor. To evaluate the aerosolizing characteristics of the CaCO 3 sorbent particle, changes in the size distribution and total particle concentration between the DTF inlet and outlet were measured. Structural changes (e.g., porosity, grain size, and morphology) of the calcined sorbent particles were estimated by BET/BJH, XRD, and SEM analyses. It was shown that sorbent particles rapidly calcined and sintered in the air atmosphere, whereas calcination was delayed in the CO 2 atmosphere due to the higher CO 2 partial pressure. Instead, the sintering effect was dominant in the CO 2 atmosphere early in the reaction. Based on the SEM images, it was shown that the reactions of sorbent particles could be explained as a grain–subgrain structure model in both the air and CO 2 atmospheres.

  20. Engineered sorbent barriers for low-level waste disposal.

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H.D.; Mitchell, S.J.; Buelt, J.L.

    1986-12-01

    The Engineered Sorbent Barriers Program at Pacific Northwest Laboratory is investigating sorbent materials to prevent the migration of soluble radio nuclides from low-level waste sites. These materials would allow water to pass, preventing the bathtub effect at humid sites. Laboratory studies identifield promising sorbent materials for three key radionuclides: for cesium, greensand; for cobalt, activated charcoal; and for strontium, synthetic zeolite or clinoptilolite. Mixtures of these sorbent materials were tested in 0.6-m-diameter columns using radioactive leachates. To simulate expected worst-case conditions, the leachate solution contained the radionuclides, competing cations, and a chelating agent and was adjusted to a pH of 5. A sorbent barrier comprised of greensand (1 wt%), activated charcoal (6 wt%), synthetic zeolite (20 wt%), and local soil (73 wt%) achieved the decontamination factors necessary to meet the regulatory performance requirements established for this study. Sorbent barriers can be applied to shallow-land burial, as backfill around the waste or engineered structures, or as backup to other liner systems. 7 refs., 14 figs., 12 tabs.

  1. Engineered sorbent barriers for low-level waste disposal

    International Nuclear Information System (INIS)

    Freeman, H.D.; Mitchell, S.J.; Buelt, J.L.

    1986-12-01

    The Engineered Sorbent Barriers Program at Pacific Northwest Laboratory is investigating sorbent materials to prevent the migration of soluble radio nuclides from low-level waste sites. These materials would allow water to pass, preventing the bathtub effect at humid sites. Laboratory studies identifield promising sorbent materials for three key radionuclides: for cesium, greensand; for cobalt, activated charcoal; and for strontium, synthetic zeolite or clinoptilolite. Mixtures of these sorbent materials were tested in 0.6-m-diameter columns using radioactive leachates. To simulate expected worst-case conditions, the leachate solution contained the radionuclides, competing cations, and a chelating agent and was adjusted to a pH of 5. A sorbent barrier comprised of greensand (1 wt%), activated charcoal (6 wt%), synthetic zeolite (20 wt%), and local soil (73 wt%) achieved the decontamination factors necessary to meet the regulatory performance requirements established for this study. Sorbent barriers can be applied to shallow-land burial, as backfill around the waste or engineered structures, or as backup to other liner systems. 7 refs., 14 figs., 12 tabs

  2. New Sorbents for Removing Arsenic From Water

    Science.gov (United States)

    McConchie, D. M.; Genc-Fuhrman, H.; Clark, M. W.; Caldicott, W.; Davies-McConchie, F. G.

    2004-12-01

    Elevated concentrations of arsenic in the drinking water used in many countries, including some of the poorest developing countries, and recognition that consuming this water can have serious consequences for human health, have led to increased investigations of ways to obtain safe water supplies. Finding new groundwater resources is a possible solution but this is a costly strategy that has no guarantee of success, particularly in areas where water is already a scarce commodity. The alternative is to treat water that is already available, but existing technologies are usually too expensive, too difficult to operate and maintain, or not completely effective when used in less developed countries or remote areas. There is therefore, an urgent need to find a simple and effective but inexpensive sorbent for arsenic that can be used to treat large volumes of water under less than ideal conditions. In this paper we present the results of field and laboratory trials that used a new, highly cost-effective, sorbent to remove arsenic from contaminated water. BauxsolT is the name given to the cocktail of minerals prepared by treating caustic bauxite refinery residues with Mg and Ca to produce a substance with a reaction pH of about 8.5, a high acid neutralizing capacity and an excellent ability to trap trace metals, metalloids and some other ionic species. The trapped ions are tightly bound by processes that include; precipitation of low solubility neoformational minerals, isomorphous substitution, solid-state diffusion, and adsorption; it is also an excellent flocculant. Although ordinary BauxsolT has an excellent ability to bind arsenate, and to a lesser extent arsenite, this ability can be further increased for particular water types by using activated BauxsolT or BauxsolT combined with small amounts of other reagents. Field trials conducted at the Gilt Edge Mine, South Dakota, showed that the addition of BauxsolT to highly sulfidic waste rock reduced the arsenic

  3. Development and application of charcoal sorbents for cryopumping fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Sedgley, D.W. (Grumman Corp., Bethpage, NY (USA). Space Systems Div.)

    1989-06-01

    Progress has been made in defining the capabilities of charcoal as the most promising absorbent to be used in cryopumps for fusion power application. The capabilities of alternative methods of cryopumping helium have been examined in a literature survey and by test, and the results are described here. Considerations include pumping speed, capacity to accumulate pumped gas, ease of reconditioning, use of alternative materials and tolerance to the fusion environment. Vacuum pumps for future fusion devices must handle large quantities of helium/hydrogen isotopes and other impurities. Cryopumps or turbomolecular pumps have demonstrated the capability on a small scale, and each has an important advantage: TMPs do not accumulate gases; cryopumps can separate helium from other effluents. This paper includes a review of a method for selecting charcoals for helium cryopumping, testing of a continuously operating cryopump system, and definition of a design that is based on the requirements of the Next European Torus. Tritium limits are satisfied. The pump design incorporates the charcoal sorbent system that has been recently developed and is based on a reasonable extrapolation of current state-of-the-art. Evaluation of alternative methods of separating helium and other gases led to selection of a movable barrier as the preferred solution. (orig.).

  4. Biochar: a green sorbent to sequester acidic organic contaminants

    Science.gov (United States)

    Sigmund, Gabriel; Kah, Melanie; Sun, Huichao; Hofmann, Thilo

    2015-04-01

    Biochar is a carbon rich product of biomass pyrolysis that exhibits a high sorption potential towards a wide variety of inorganic and organic contaminants. Because it is a valuable soil additive and a potential carbon sink that can be produced from renewable resources, biochar has gained growing attention for the development of more sustainable remediation strategies. A lot of research efforts have been dedicated to the sorption of hydrophobic contaminants and metals to biochar. Conversely, the understanding of the sorption of acidic organic contaminants remains limited, and questions remain on the influence of biochar characteristics (e.g. ash content) on the sorption behaviour of acidic organic contaminants. To address this knowledge gap, sorption batch experiments were conducted with a series of structurally similar acidic organic contaminants covering a range of dissociation constant (2,4-D, MCPA, 2,4-DB and triclosan). The sorbents selected for experimentation included a series of 10 biochars covering a range of characteristics, multiwalled carbon nanotubes as model for pure carbonaceous phases, and an activated carbon as benchmark. Overall, sorption coefficient [L/kg] covered six orders of magnitude and generally followed the order 2,4-D pH dependent lipophilicity ratio (i.e. D instead of Kow), ash content and ionic strength are key factors influencing the sorption of acidic organic contaminants to biochars. Overall, the identified factors, as well as the environmental matrix, should be carefully considered when selecting the type of biochar for sequestration purposes.

  5. Understanding the low uptake of bone-anchored hearing aids: a review.

    Science.gov (United States)

    Powell, R; Wearden, A; Pardesi, S M; Green, K

    2017-03-01

    Bone-anchored hearing aids improve hearing for patients for whom conventional behind-the-ear aids are problematic. However, uptake of bone-anchored hearing aids is low and it is important to understand why this is the case. A narrative review was conducted. Studies examining why people accept or decline bone-anchored hearing aids and satisfaction levels of people with bone-anchored hearing aids were reviewed. Reasons for declining bone-anchored hearing aids included limited perceived benefits, concerns about surgery, aesthetic concerns and treatment cost. No studies providing in-depth analysis of the reasons for declining or accepting bone-anchored hearing aids were identified. Studies of patient satisfaction showed that most participants reported benefits with bone-anchored hearing aids. However, most studies used cross-sectional and/or retrospective designs and only included people with bone-anchored hearing aids. Important avenues for further research are in-depth qualitative research designed to fully understand the decision-making process for bone-anchored hearing aids and rigorous quantitative research comparing satisfaction of people who receive bone-anchored hearing aids with those who receive alternative (or no) treatments.

  6. Undergraduate Nursing Students' Understandings of Mental Health: A Review of the Literature.

    Science.gov (United States)

    Barry, Sinead; Ward, Louise

    2017-02-01

    The purpose of this literature review was to identify research and current literature surrounding nursing students' understandings of mental health. The aim is to share findings from an extensive international and national literature review exploring undergraduate nurse education specific to mental health content. Data were collected utilising a comprehensive search of electronic databases including CINAHL (EBSCO), MEDLINE, and PsycINFO 1987-(Ovid) from 2008 to 2016. The initial search terms were altered to include undergraduate, mental health, nursing, education, experience, and knowledge. Three content themes emerged which included: 1. Undergraduate nursing students' knowledge has been considered compromised due to concerns relating to the variation and inconsistencies within the comprehensive nursing curriculums representation of mental health, 2. Undergraduate nursing students knowledge of mental health is thought to be compromised due to the quality of mental health theoretical and experiential learning opportunities, and 3. Research indicates that nursing students' knowledge of mental health was influenced by their experience of undertaking mental health content. Based on these findings greater consideration of students' understandings of mental health is required.

  7. Evaluation of Solid Sorbents As A Retrofit Technology for CO{sub 2} Capture from Coal-Fired Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Krutka, Holly; Sjostrom, Sharon

    2011-07-31

    limitations related to the CO{sub 2} uptake rate. Three additional supported amine materials, sorbents AX, F, and BN, were selected for evaluation using the 1 kW pilot at Sherco. Sorbent AX was operated in batch mode and performed similarly to sorbent R (i.e. could achieve up to 90% removal when given adequate regeneration time). Sorbent BN was not expected to be subject to the same mass diffusion limitations as experienced with sorbent R. When sorbent BN was used in continuous mode the steady state CO{sub 2} removal was approximately double that of sorbent R, which highlighted the importance of sorbents without kinetic limitations. Many different processes and equipment designs exist that may be applicable for postcombustion CO{sub 2} capture using solids in a temperature-swing system. A thorough technology survey was completed to identify the most promising options, which were grouped and evaluated based on the four main unit operations involved with sorbent based capture: Adsorption; Heating and cooling, or heat transfer; Conveying; Desorption. The review included collecting information from a wide variety of sources, including technology databases, published papers, advertisements, web searches, and vendor interviews. Working with power producers, scoring sheets were prepared and used to compare the different technology options. Although several technologies were interesting and promising, those that were selected for the final conceptual design were commercially available and performed multiple steps simultaneously. For the adsorption step, adsorption and conveying were both accomplished in a circulating fluidized bed. A rotary kiln was selected for desorption and cooling because it can simultaneously accomplish conveying and effective heat transfer. The final technology selection was used to complete preliminary costs assessments for a conceptual 500 MW CO{sub 2} capture process. The high level cost analysis was completed to determine the key cost drivers. The

  8. Tunable polymeric sorbent materials for fractionation of model naphthenates.

    Science.gov (United States)

    Mohamed, Mohamed H; Wilson, Lee D; Headley, John V

    2013-04-04

    The sorption properties are reported for several examples of single-component carboxylic acids representing naphthenic acids (NAs) with β-cyclodextrin (β-CD) based polyurethane sorbents. Seven single-component examples of NAs were chosen with variable z values, carbon number, and chemical structure as follows: 2-hexyldecanoic acid (z = 0 and C = 16; S1), n-caprylic acid (z = 0 and C = 8; S2), trans-4-pentylcyclohexanecarboxylic acid (z = -2 and C = 12; S3), 4-methylcyclohexanecarboxylic acid (z = -2 and C = 8; S4), dicyclohexylacetic acid (z = -4; C = 14; S5), 4-pentylbicyclo[2.2.2]octane-1-carboxylic acid (z = -4; C = 14; S6), and lithocholic acid (z = -6; C = 24; S7). The copolymer sorbents were synthesized at three relative β-CD:diisocyanate mole ratios (i.e., 1:1, 1:2, and 1:3) using 4,4'-dicyclohexylmethane diisocyanate (CDI) and 4,4'-diphenylmethane diisocyanate (MDI). The sorption properties of the copolymer sorbents were characterized using equilibrium sorption isotherms in aqueous solution at pH 9.00 with electrospray ionization mass spectrometry. The equilibrium fraction of the unbound carboxylate anions was monitored in the aqueous phase. The sorption properties of the copolymer sorbents (i.e., Qm) were obtained from the Sips isotherm model. The Qm values generally decrease as the number of accessible β-CD inclusion sites in the copolymer framework decreases. The chemical structure of the adsorbates played an important role in their relative uptake, as evidenced by the adsorbate lipophilic surface area (LSA) and the involvement of hydrophobic effects. The copolymers exhibit molecular selective sorption of the single-component carboxylates in mixtures which suggests their application as sorbents for fractionation of mixtures of NAs. By comparison, granular activated carbon (GAC) and chitosan sorbents did not exhibit any significant molecular selective sorption relative to the copolymer materials; however, evidence of variable sorption capacity was

  9. Understanding Factors that Shape Gender Attitudes in Early Adolescence Globally: A Mixed-Methods Systematic Review

    Science.gov (United States)

    Gibbs, Susannah; Blum, Robert Wm; Moreau, Caroline; Chandra-Mouli, Venkatraman; Herbert, Ann; Amin, Avni

    2016-01-01

    review suggest that young adolescents in different cultural settings commonly endorse norms that perpetuate gender inequalities, and that parents and peers are especially central in shaping such attitudes. Programs to promote equitable gender attitudes thus need to move beyond a focus on individuals to target their interpersonal relationships and wider social environments. Such programs need to start early and be tailored to the unique needs of sub-populations of boys and girls. Longitudinal studies, particularly from low-and middle-income countries, are needed to better understand how gender attitudes unfold in adolescence and to identify the key points for intervention. PMID:27341206

  10. Understanding Factors that Shape Gender Attitudes in Early Adolescence Globally: A Mixed-Methods Systematic Review.

    Science.gov (United States)

    Kågesten, Anna; Gibbs, Susannah; Blum, Robert Wm; Moreau, Caroline; Chandra-Mouli, Venkatraman; Herbert, Ann; Amin, Avni

    2016-01-01

    Early adolescence (ages 10-14) is a period of increased expectations for boys and girls to adhere to socially constructed and often stereotypical norms that perpetuate gender inequalities. The endorsement of such gender norms is closely linked to poor adolescent sexual and reproductive and other health-related outcomes yet little is known about the factors that influence young adolescents' personal gender attitudes. To explore factors that shape gender attitudes in early adolescence across different cultural settings globally. A mixed-methods systematic review was conducted of the peer-reviewed literature in 12 databases from 1984-2014. Four reviewers screened the titles and abstracts of articles and reviewed full text articles in duplicate. Data extraction and quality assessments were conducted using standardized templates by study design. Thematic analysis was used to synthesize quantitative and qualitative data organized by the social-ecological framework (individual, interpersonal and community/societal-level factors influencing gender attitudes). Eighty-two studies (46 quantitative, 31 qualitative, 5 mixed-methods) spanning 29 countries were included. Ninety percent of studies were from North America or Western Europe. The review findings indicate that young adolescents, across cultural settings, commonly express stereotypical or inequitable gender attitudes, and such attitudes appear to vary by individual sociodemographic characteristics (sex, race/ethnicity and immigration, social class, and age). Findings highlight that interpersonal influences (family and peers) are central influences on young adolescents' construction of gender attitudes, and these gender socialization processes differ for boys and girls. The role of community factors (e.g. media) is less clear though there is some evidence that schools may reinforce stereotypical gender attitudes among young adolescents. The findings from this review suggest that young adolescents in different cultural

  11. Understanding Factors that Shape Gender Attitudes in Early Adolescence Globally: A Mixed-Methods Systematic Review.

    Directory of Open Access Journals (Sweden)

    Anna Kågesten

    Full Text Available Early adolescence (ages 10-14 is a period of increased expectations for boys and girls to adhere to socially constructed and often stereotypical norms that perpetuate gender inequalities. The endorsement of such gender norms is closely linked to poor adolescent sexual and reproductive and other health-related outcomes yet little is known about the factors that influence young adolescents' personal gender attitudes.To explore factors that shape gender attitudes in early adolescence across different cultural settings globally.A mixed-methods systematic review was conducted of the peer-reviewed literature in 12 databases from 1984-2014. Four reviewers screened the titles and abstracts of articles and reviewed full text articles in duplicate. Data extraction and quality assessments were conducted using standardized templates by study design. Thematic analysis was used to synthesize quantitative and qualitative data organized by the social-ecological framework (individual, interpersonal and community/societal-level factors influencing gender attitudes.Eighty-two studies (46 quantitative, 31 qualitative, 5 mixed-methods spanning 29 countries were included. Ninety percent of studies were from North America or Western Europe. The review findings indicate that young adolescents, across cultural settings, commonly express stereotypical or inequitable gender attitudes, and such attitudes appear to vary by individual sociodemographic characteristics (sex, race/ethnicity and immigration, social class, and age. Findings highlight that interpersonal influences (family and peers are central influences on young adolescents' construction of gender attitudes, and these gender socialization processes differ for boys and girls. The role of community factors (e.g. media is less clear though there is some evidence that schools may reinforce stereotypical gender attitudes among young adolescents.The findings from this review suggest that young adolescents in different

  12. Understanding the impact of visual arts interventions for people living with dementia: a realist review protocol.

    Science.gov (United States)

    Windle, Gill; Gregory, Samantha; Newman, Andrew; Goulding, Anna; O'Brien, Dave; Parkinson, Clive

    2014-08-15

    Arts-based activities are being increasingly suggested as a valuable activity for people living with dementia in terms of countering the negative aspects of their condition. The potential for such programmes to improve a broad range of psychosocial outcomes is suggested in some studies. However, there is largely an absence of rigorous methodology to demonstrate the benefits, and research results are mixed. Practice variability in terms of the content, contexts and implementation of such interventions raises challenges in terms of identifying an optimal arts programme model that could be adopted by other service providers. Understanding how interventions may have the best chance at broad implementation success and uptake is limited. A realist review will be undertaken. This aims to understand how visual arts interventions influence outcomes in people living with dementia. The review will explore how the context, that is the circumstances which enable or constrain, affect outcomes through the activation of mechanisms. An early scoping search and a stakeholder survey formulated the preliminary programme theory. A systematic literature search across a broad range of disciplines (arts, humanities, social sciences, health) will be undertaken to identify journal articles and grey literature. Data will be extracted in relation to the programme theory, contextual factors, mechanisms and outcomes and their configurations, background information about the study design and participant characteristics, detail about the quantity ('dose') of an intervention, theoretical perspectives proposed by the authors of the paper and further theorising by the reviewer. Thematic connections/patterns will be sought across the extracted data, identifying patterns amongst contextual factors, the mechanisms they trigger and the associated outcomes. Along with stakeholder engagement and validation, this review will help inform the development of an optimal, replicable arts intervention for people

  13. Understanding the health of veterans who are homeless: A review of the literature.

    Science.gov (United States)

    Weber, Jillian; Lee, Rebecca C; Martsolf, Donna

    2017-09-01

    The United States Department of Housing and Urban Development estimates that almost 50,000 veterans are homeless on any given night. Homeless veterans are at greater risk of health disparities than their housed counterparts due to the multifactorial nature of their health and social needs. The Department of Veterans Affairs, in collaboration with more than a dozen other federal agencies, has concentrated efforts to improve the health of this vulnerable population while enacting a plan to eliminate veteran homelessness within the near future. Understanding the unique health needs of veterans who are homeless allows the profession of nursing to better support these efforts. The purpose of this literature review was to provide comprehensive knowledge to nurses about the health of homeless veterans for their use in clinical practice, research, and in contributing to the positive health outcomes for this vulnerable population. © 2017 Wiley Periodicals, Inc.

  14. A narrative review of recent progress in understanding the relationship between tuberculosis and protein energy malnutrition.

    Science.gov (United States)

    Hood, M L H

    2013-11-01

    Protein energy malnutrition (PEM) and tuberculosis (TB) are the major public health issues, particularly in the developing country setting. Malnutrition is an underlying cause of many deaths and when left untreated devastates normal physical and cognitive development. TB continues to gather momentum as a serious infectious killer. They have both rightly been highlighted as important global health issues by their inclusion in the Millennium Development Goals. But what is known of their relationship with one another? It is historically accepted that PEM and TB have a synergistic relationship adversely having an impact on one another. However, researchers have sought to apply this understanding in an examination of the relationship between TB and PEM with often inconclusive results. This narrative review of recently published research and current knowledge may help delineate the association between PEM and TB mortality. Such results will assist future research in this important area of health--an area lacking evidence-based guidance.

  15. Understanding the influence of the snack definition on the association between snacking and obesity: a review.

    Science.gov (United States)

    Gregori, Dario; Foltran, Francesca; Ghidina, Marco; Berchialla, Paola

    2011-05-01

    The aim of the present study is to understand how different definitions of snacking influence the estimated probability of obesity in the presence of concurrent risk factors. Factors influencing obesity were evaluated by reviewing the relevant literature through a PUBMED search. Six different modalities to define snack consumption were identified. A Bayesian network model in which nodes represent the variables that the retrieved studies indicate as affecting the probability of obesity was implemented and used to estimate the individual risk of developing obesity taking into account the concurrent effect of the considered risk factors. For a subject with a given profile of factors, the probability of obesity varies according to the chosen definition of snacking, up to maximum of 70%. The variability of the probability of obesity attributable to the chosen definition of snacking is very high and may threaten any conclusion about the effect of snacking, which may be related to the specific definitions adopted in the study.

  16. Understanding the impact of political violence in childhood: a theoretical review using a social identity approach.

    Science.gov (United States)

    Muldoon, Orla T

    2013-12-01

    The present paper reviews the literature that has assessed the psychological impact of political violence on children. Concern for those growing up in situations of political violence has resulted in two areas of research within psychology: the first considers children as victims of conflict and considers the mental health consequences of political violence. The second considers children as protagonists or aggressors in conflict and considers related moral and attitudinal consequences of exposure to political violence. These two literatures are most often considered separately. Here the two strands of research are brought together using a social identity framework, allowing apparently divergent findings to be integrated into a more coherent understanding of the totality of consequences for children and young people growing up in situations of armed conflict. © 2013.

  17. Tobacco counter-advertising: a review of the literature and a conceptual model for understanding effects.

    Science.gov (United States)

    Agostinelli, Gina; Grube, Joel W

    2003-01-01

    The tobacco counter-advertising literature is reviewed as it relates to basic process questions concerning what makes counter-advertisements effective. Limitations in addressing (a) counter-advertisement content and the psychological mediators targeted, (b) counter-advertisement style and the affective reactions targeted, (c) prior smoking experience, and (d) other audience factors are enumerated. A theoretical model based on alcohol advertising research is presented to address those limitations. The model addresses the practical research question of predicting when tobacco counter-advertising will work by examining the independent influence of each of these enumerated factors, as well as how these factors operate in concert, qualifying each other. The model also addresses the process question of explaining how counter-advertising works by identifying affective and cognitive processes as mediators. By understanding the processes that underlie the qualified findings, one can better advise the designers of tobacco counter-advertisements how to be more effective.

  18. Tributyl phosphate removal from reprocessing off-gas streams using a selected sorbent

    International Nuclear Information System (INIS)

    Parker, G.B.

    1980-01-01

    Laboratory experiments used small laboratory-scale columns packed with selected sorbent materials to remove tributyl phosphate (TBP) and iodine at conditions approaching those in actual reprocessing off-gas streams. The sorbent materials for TBP removal were placed upstream of iodine sorbent materials to protect the iodine sorbent from the deleterious effects of TBP. Methyl iodide in an airstream containing 30% TBP in normal paraffin hydrocarbons (NPH) and water vapor was metered to two packed columns of sorbents simultaneously (in parallel). One column contained a segment of 8-in. x 14-in. mesh alumina sorbent for TBP removal, the other did not. The measure of the effectiveness of TBP sorbent materials for TBP removal was determined by comparing the iodine retention of the iodine sorbent materials in the two parallel columns. Results from an 18 wt % Ag substituted mordenite iodine sorbent indicated that the iodine retention capacity of the sorbent was reduced 60% by the TBP and that the column containing iodine sorbent material protected by the alumina TBP sorbent retained 30 times more iodine than the column without TBP sorbent. TBP concentration was up to 500 mg/m 3 . Similar experiments using a 7 wt % Ag impregnated silica gel indicated that the TBP vapor had little effect on the iodine retention of the silica gel material. The stoichiometric maximum amount of iodine was retained by the silica gel material. Further experiments were conducted assessing the effects of NO 2 on iodine retention of this 7 wt % Ag sorbent. After the two columns were loaded with iodine in the presence of TBP (in NPH), one column was subjected to 2 vol % NO 2 in air. From visual comparison of the two columns, it appeared that the NO 2 regenerated the silica gel iodine sorbent and that iodine was washed off the silica gel iodine sorbent leaving the sorbent in the original state

  19. Review Of Mechanistic Understanding And Modeling And Uncertainty Analysis Methods For Predicting Cementitious Barrier Performance

    International Nuclear Information System (INIS)

    Langton, C.; Kosson, D.

    2009-01-01

    Cementitious barriers for nuclear applications are one of the primary controls for preventing or limiting radionuclide release into the environment. At the present time, performance and risk assessments do not fully incorporate the effectiveness of engineered barriers because the processes that influence performance are coupled and complicated. Better understanding the behavior of cementitious barriers is necessary to evaluate and improve the design of materials and structures used for radioactive waste containment, life extension of current nuclear facilities, and design of future nuclear facilities, including those needed for nuclear fuel storage and processing, nuclear power production and waste management. The focus of the Cementitious Barriers Partnership (CBP) literature review is to document the current level of knowledge with respect to: (1) mechanisms and processes that directly influence the performance of cementitious materials (2) methodologies for modeling the performance of these mechanisms and processes and (3) approaches to addressing and quantifying uncertainties associated with performance predictions. This will serve as an important reference document for the professional community responsible for the design and performance assessment of cementitious materials in nuclear applications. This review also provides a multi-disciplinary foundation for identification, research, development and demonstration of improvements in conceptual understanding, measurements and performance modeling that would be lead to significant reductions in the uncertainties and improved confidence in the estimating the long-term performance of cementitious materials in nuclear applications. This report identifies: (1) technology gaps that may be filled by the CBP project and also (2) information and computational methods that are in currently being applied in related fields but have not yet been incorporated into performance assessments of cementitious barriers. The various

  20. REVIEW OF MECHANISTIC UNDERSTANDING AND MODELING AND UNCERTAINTY ANALYSIS METHODS FOR PREDICTING CEMENTITIOUS BARRIER PERFORMANCE

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.; Kosson, D.

    2009-11-30

    Cementitious barriers for nuclear applications are one of the primary controls for preventing or limiting radionuclide release into the environment. At the present time, performance and risk assessments do not fully incorporate the effectiveness of engineered barriers because the processes that influence performance are coupled and complicated. Better understanding the behavior of cementitious barriers is necessary to evaluate and improve the design of materials and structures used for radioactive waste containment, life extension of current nuclear facilities, and design of future nuclear facilities, including those needed for nuclear fuel storage and processing, nuclear power production and waste management. The focus of the Cementitious Barriers Partnership (CBP) literature review is to document the current level of knowledge with respect to: (1) mechanisms and processes that directly influence the performance of cementitious materials (2) methodologies for modeling the performance of these mechanisms and processes and (3) approaches to addressing and quantifying uncertainties associated with performance predictions. This will serve as an important reference document for the professional community responsible for the design and performance assessment of cementitious materials in nuclear applications. This review also provides a multi-disciplinary foundation for identification, research, development and demonstration of improvements in conceptual understanding, measurements and performance modeling that would be lead to significant reductions in the uncertainties and improved confidence in the estimating the long-term performance of cementitious materials in nuclear applications. This report identifies: (1) technology gaps that may be filled by the CBP project and also (2) information and computational methods that are in currently being applied in related fields but have not yet been incorporated into performance assessments of cementitious barriers. The various

  1. Understanding how appraisal of doctors produces its effects: a realist review protocol.

    Science.gov (United States)

    Brennan, Nicola; Bryce, Marie; Pearson, Mark; Wong, Geoff; Cooper, Chris; Archer, Julian

    2014-06-23

    UK doctors are now required to participate in revalidation to maintain their licence to practise. Appraisal is a fundamental component of revalidation. However, objective evidence of appraisal changing doctors' behaviour and directly resulting in improved patient care is limited. In particular, it is not clear how the process of appraisal is supposed to change doctors' behaviour and improve clinical performance. The aim of this research is to understand how and why appraisal of doctors is supposed to produce its effect. Realist review is a theory-driven interpretive approach to evidence synthesis. It applies realist logic of inquiry to produce an explanatory analysis of an intervention that is, what works, for whom, in what circumstances, in what respects. Using a realist review approach, an initial programme theory of appraisal will be developed by consulting with key stakeholders in doctors' appraisal in expert panels (ethical approval is not required), and by searching the literature to identify relevant existing theories. The search strategy will have a number of phases including a combination of: (1) electronic database searching, for example, EMBASE, MEDLINE, the Cochrane Library, ASSIA, (2) 'cited by' articles search, (3) citation searching, (4) contacting authors and (5) grey literature searching. The search for evidence will be iteratively extended and refocused as the review progresses. Studies will be included based on their ability to provide data that enable testing of the programme theory. Data extraction will be conducted, for example, by note taking and annotation at different review stages as is consistent with the realist approach. The evidence will be synthesised using realist logic to interrogate the final programme theory of the impact of appraisal on doctors' performance. The synthesis results will be written up according to RAMESES guidelines and disseminated through peer-reviewed publication and presentations. The protocol is registered with

  2. Post combustion carbon capture - solid sorbents and membranes

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, R.M. [IEA Clean Coal Centre, London (United Kingdom)

    2009-04-15

    This report follows on from that on solvent scrubbing for post-combustion carbon capture from coal-fired power plants by considering the use of solid sorbents and membranes instead of solvents. First, mesoporous and microporous adsorbents are discussed: carbon-based adsorbents, zeolites, hydrotalcites and porous crystals. Attempts have been made to improve the performance of the porous adsorbent by functionalising them with nitrogen groups and specifically, amine groups to react with CO{sub 2} and thus enhance the physical adsorption properties. Dry, regenerable solid sorbents have attracted a good deal of research. Most of the work has been on the carbonation/calcination cycle of natural limestone but there have also been studies of other calcium-based sorbents and alkali metal-based sorbents. Membranes have also been studied as potential post-combustion capture devices. Finally, techno-economic studies predicting the economic performance of solid sorbents and membranes are discussed. The report is available from IEA Clean Coal Centre as report no. CCC/144. See Coal Abstracts entry April 2009 00406. 340 refs., 21 figs., 8 tabs.

  3. Oil spill sorbents: Testing protocol and certification listing program

    International Nuclear Information System (INIS)

    Cooper, D.; Gausemel, I.

    1993-01-01

    Environment Canada's Emergencies Engineering Division is spearheading a program in conjunction with the Canadian General Standards Board that would see the development of a certification and listing program in addition to a national standard for the testing of sorbent materials. Funding for this program is provided by Environment Canada (EC), Canadian Coast Guard (CCG), Marine Spill Response Corporation (MSRC), US Coast Guard (USCG), and US Minerals Management Service (MMS). The test methods are based upon those defined by the American Society for Testing and Materials and previous test methods developed by Environment Canada for our series of reports entitled Selection Criteria and Laboratory Evaluation of Oil Spill Sorbents. This series, which was started in 1975, encompasses a number of commercially available oil spill sorbents tested with different petroleum products and hydrocarbon solvents. The testing program will categorize the sorbents according to their operating characteristics. The main categories are oil spills on water, oil spills on land, and industrial use. The characteristics to be evaluated with the new test protocols include initial and maximum sorption capacities, water pickup, buoyancy, reuse potential, retention profile, disintegration (material integrity), and ease of application and retrieval. In the near future are plans to incorporate changes to the test that would involve increasing the list of test liquids to encompass spills in an industrial setting, in addition to testing sorbent booms and addressing the disposal problem

  4. Engineered sorbent barriers for low-level waste disposal

    International Nuclear Information System (INIS)

    Mitchell, S.J.; Freeman, H.D.; Buelt, J.L.

    1986-01-01

    Pacific Northwest Laboratory is developing sorbent materials to prevent the migration of radionuclides from low-level waste sites. These materials would allow water to pass, preventing the bathtub effect at humid sites. Screening studies identified promising sorbent materials for three key radionuclides: for cesium, greensand; for cobalt, activated charcoal; and for strontium, synthetic zeolite or clinoptilolite. Mixtures of these sorbent materials were tested in 0.6-m-diameter columns using radioactive leachates. To simulate expected worst-case conditions, the leachate solution contained the radionuclides, competing cations, and a chelating agent, adjusted to a pH of 5. A sorbent barrier comprised of greensand (1 wt %), activated charcoal (6 wt %), synthetic zeolite (20 wt %), and soil (73 wt %) achieved the decontamination factors necessary to meet the regulatory performance requirements established for this study. Sorbent barriers can be applied to shallow land burial, as backfill around the waste or engineered structures, or as backup to other liner systems. 2 refs., 6 figs., 3 tabs

  5. Cheap carbon sorbents produced from lignite by catalytic pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, B.N.; Schchipko, M.L. [Inst. of Chemistry of Natural Organic Materials, Akademgorodok, Krasnoyarsk (Russian Federation)

    1995-12-01

    Some data are presented describing the new technology of carbon sorbent production from powdered lignite in the installation with fluidized bed of catalyst. It was shown the different types of char products with extended pore structure and high sorption ability can be produced from cheap and accessible lignite of Kansk-Achinsk coal pit in pilot installation with fluidized bed of Al-Cu-Cr oxide catalyst or catalytically active slag materials. In comparison with the conventional technologies of pyrolysis the catalytic pyrolysis allows to increase by 3-5 times the process productivity and to decrease significantly the formation of harmful compounds. The latter is accomplished by complete oxidation of gaseous pyrolysis products in the presence of catalysts and by avoiding the formation of pyrolysis tars - the source of cancerogenic compounds. The technology of cheap powdered sorbent production from lignites makes possible to obtain from lignite during the time of pyrolysis only a few seconds char products with porosity up to 0.6 cm{sup 3} /g, and specific surface area more than 400 m{sup 3} /g. Some methods of powdered chars molding into carbon materials with the different shape were proved for producing of firmness sorbents. Cheap carbon sorbents obtained by thermocatalytic pyrolysis can be successfully used in purification of different industrial pollutants as one-time sorbent or as adsorbents of long-term application with periodic regeneration.

  6. Ecologically pure sorbents for power system of Myanmar

    Science.gov (United States)

    Nikitina, I. S.; Moryganova, Y. A.; Maung, Ko Ko; Arefeva, E. A.

    2017-11-01

    Currently, one of the most important problems of the thermal power plant, and many industrial enterprises in different countries is a wastewater treatment for oil products. When choosing the good sorbents is necessary to consider not only the properties and efficiency of the recommended materials, but also the cost, the possibility of environmentally friendly disposal of used sorbents and the possibility of using secondary resources. The purpose of this paper is to study the possibility of using agricultural waste in Myanmar as the sorbents in wastewater treatment containing oil products. The results of experiments have confirmed that rice hulls, and coconut fiber can be effectively used as the sorbents in wastewater treatment containing oil products at concentrations up to 10 mg/l. According to comparative analysis with the conventional sorbent-activated birch carbon (BAC-A) in the Russian power industry has shown that coconut fiber has very good sorption capacity and it is available to use as the raw materials for industries, which does not require to regenerate after using it and can be directly recycled in the factory.

  7. Dual layer hollow fiber sorbents: Concept, fabrication and characterization

    KAUST Repository

    Bhandari, Dhaval

    2013-02-01

    Hollow fiber sorbents are pseudo-monolithic separations materials created with fiber spinning technology using a polymer \\'binder\\', impregnated with high loadings of sorbent \\'fillers\\' [1]. To increase purified gas recovery during the sorption step and to ensure consistent sorption capacity over repeated cycles, a dense, thin polymer barrier layer on the fiber sorbents is needed to allow only thermal interactions between the sorbate loaded layer and the thermal regeneration fluid. This paper considers materials and methods to create delamination-free dual layer fiber sorbents, with a porous core and a barrier sheath layer formed using a simultaneous co-extrusion process. Low permeability polymers were screened for sheath layer creation, with the core layer comprising cellulose acetate polymer as binder and zeolite NaY as sorbent fillers. Appropriate core and sheath layer dope compositions were determined by the cloud-point method and rheology measurements. The morphology of the as-spun fibers was characterized in detail by SEM, EDX and gas permeation analysis. A simplified qualitative model is described to explain the observed fiber morphology. The effects of core, sheath spin dope and bore fluid compositions, spinning process parameters such as air-gap height, spin dope and coagulation bath temperatures, and elongation draw ratio are examined in detail. © 2012 Elsevier B.V. All rights reserved.

  8. Sorbent application on the base of chitosan for radionuclides separation

    International Nuclear Information System (INIS)

    Pivarciova, L.

    2016-01-01

    Radioactive waste contains enormous amounts of radionuclides, which pollute the environment and can cause serious chemical and radiological toxicity threats to lower and higher living organism. Alternative process for the removal of heavy metal ions and radionuclides is sorption, which utilizes various certain natural materials of biological origin. Amino-polysaccharide-based sorbents e.g. chitosan represent suitable materials for binding of metal oxo-anion species because of numerous functional groups -OH and -NH_2 because of their suitable H-bond donor and acceptor sites. The sorbents on the base chitosan prepared through chemical modification were used for removal and separation certain radionuclides from aqueous media. The aim of this work was the study of physicochemical properties of prepared sorbents. The specific surface of sorbents was characterized with BET methods. Point of zero charge was identified with potentiometric titration. The size of particles and shape of sorbents were determined by scanning electron microscope. The sorption experiments for selected radionuclides were conducted under static and dynamic conditions. The effect of various parameters on the sorption "9"9"mTc, "6"0Co and the effect of pH on the separation of radionuclide mixture in the solution were studied. (author)

  9. Pre-Service Primary Teachers' Knowledge and Understanding of Geography and Its Teaching: A Review

    Science.gov (United States)

    Catling, Simon

    2014-01-01

    It is a decade since the last review of the geographical understandings of pre-service primary teachers. Examining the range of research about novice primary teachers' geographical and environmental knowledge and understanding, it is clear there have been limited follow up studies, and there remain important gaps in the research. Research relevant…

  10. Review of the Scientific Understanding of Radioactive Waste at the U.S. DOE Hanford Site.

    Science.gov (United States)

    Peterson, Reid A; Buck, Edgar C; Chun, Jaehun; Daniel, Richard C; Herting, Daniel L; Ilton, Eugene S; Lumetta, Gregg J; Clark, Sue B

    2018-01-16

    This Critical Review reviews the origin and chemical and rheological complexity of radioactive waste at the U.S. Department of Energy Hanford Site. The waste, stored in underground tanks, was generated via three distinct processes over decades of plutonium extraction operations. Although close records were kept of original waste disposition, tank-to-tank transfers and conditions that impede equilibrium complicate our understanding of the chemistry, phase composition, and rheology of the waste. Tank waste slurries comprise particles and aggregates from nano to micro scales, with varying densities, morphologies, heterogeneous compositions, and complicated responses to flow regimes and process conditions. Further, remnant or changing radiation fields may affect the stability and rheology of the waste. These conditions pose challenges for transport through conduits or pipes to treatment plants for vitrification. Additionally, recalcitrant boehmite degrades glass quality and the high aluminum content must be reduced prior to vitrification for the manufacture of waste glass of acceptable durability. However, caustic leaching indicates that boehmite dissolves much more slowly than predicted given surface normalized rates. Existing empirical models based on ex situ experiments and observations generally only describe material balances and have not effectively predicted process performance. Recent advances in the areas of in situ microscopy, aberration-corrected transmission electron microscopy, theoretical modeling across scales, and experimental methods for probing the physics and chemistry at mineral-fluid and mineral-mineral interfaces are being implemented to build robustly predictive physics-based models.

  11. Understanding the Self in Individuals with Autism Spectrum Disorders (ASD: A Review of Literature

    Directory of Open Access Journals (Sweden)

    Ann X. Huang

    2017-08-01

    Full Text Available When the system of self is explored in individuals with Autism Spectrum Disorders (ASDs, it is important to measure it via both their own perceptions of the self and their understanding of others’ perceptions on themselves at a multidimensional level. This paper reviews existing research in this area using a three-dimension approach. Researchers have found that impairments in the self-system are usually correlated with these individuals’ social and cognitive functioning levels: high functioning individuals with ASD who have higher IQ are found to have better awareness of their limitations in social and communication domains than those with lower IQ. Many researchers believe that there are impairments in the psychological (but not physical self in individuals with ASD, such as theory of mind deficits due to social and communicative impairments. On the other hand, some researchers argue that individuals with ASD have selective rather than global impairments in the self. In other words, the impairment usually lies in a specific aspect of functioning in individuals with ASD. Insights from the review of existing literature on this topic may be able to shed some lights on the development of effective intervention programs to improve social communication deficits in this population.

  12. Understanding diagnostic variability in breast pathology: lessons learned from an expert consensus review panel

    Science.gov (United States)

    Allison, Kimberly H; Reisch, Lisa M; Carney, Patricia A; Weaver, Donald L; Schnitt, Stuart J; O’Malley, Frances P; Geller, Berta M; Elmore, Joann G

    2015-01-01

    Aims To gain a better understanding of the reasons for diagnostic variability, with the aim of reducing the phenomenon. Methods and results In preparation for a study on the interpretation of breast specimens (B-PATH), a panel of three experienced breast pathologists reviewed 336 cases to develop consensus reference diagnoses. After independent assessment, cases coded as diagnostically discordant were discussed at consensus meetings. By the use of qualitative data analysis techniques, transcripts of 16 h of consensus meetings for a subset of 201 cases were analysed. Diagnostic variability could be attributed to three overall root causes: (i) pathologist-related; (ii) diagnostic coding/study methodology-related; and (iii) specimen-related. Most pathologist-related root causes were attributable to professional differences in pathologists’ opinions about whether the diagnostic criteria for a specific diagnosis were met, most frequently in cases of atypia. Diagnostic coding/study methodology-related root causes were primarily miscategorizations of descriptive text diagnoses, which led to the development of a standardized electronic diagnostic form (BPATH-Dx). Specimen-related root causes included artefacts, limited diagnostic material, and poor slide quality. After re-review and discussion, a consensus diagnosis could be assigned in all cases. Conclusions Diagnostic variability is related to multiple factors, but consensus conferences, standardized electronic reporting formats and comments on suboptimal specimen quality can be used to reduce diagnostic variability. PMID:24511905

  13. Reviewing the History of Pandemic Influenza: Understanding Patterns of Emergence and Transmission

    Science.gov (United States)

    Saunders-Hastings, Patrick R.; Krewski, Daniel

    2016-01-01

    For centuries, novel strains of influenza have emerged to produce human pandemics, causing widespread illness, death, and disruption. There have been four influenza pandemics in the past hundred years. During this time, globalization processes, alongside advances in medicine and epidemiology, have altered the way these pandemics are experienced. Drawing on international case studies, this paper provides a review of the impact of past influenza pandemics, while examining the evolution of our understanding of, and response to, these viruses. This review argues that pandemic influenza is in part a consequence of human development, and highlights the importance of considering outbreaks within the context of shifting global landscapes. While progress in infectious disease prevention, control, and treatment has improved our ability to respond to such outbreaks, globalization processes relating to human behaviour, demographics, and mobility have increased the threat of pandemic emergence and accelerated global disease transmission. Preparedness planning must continue to evolve to keep pace with this heightened risk. Herein, we look to the past for insights on the pandemic experience, underlining both progress and persisting challenges. However, given the uncertain timing and severity of future pandemics, we emphasize the need for flexible policies capable of responding to change as such emergencies develop. PMID:27929449

  14. Understanding HIV-related posttraumatic stress disorder in South Africa: a review and conceptual framework.

    Science.gov (United States)

    Young, Charles

    2011-06-01

    A number of epidemiological studies have attempted to measure the prevalence of HIV-related posttraumatic stress disorder (PTSD) in sub-Saharan Africa. A systematic review of the literature identified eight relevant studies that put current estimates of the prevalence of HIV-related PTSD between 4.2% and 40%. Even the lower estimates suggest that PTSD in response to the trauma of being diagnosed and living with HIV is a significant mental health burden. However, a conceptual framework to advance our understanding of the prevalence and phenomenology of HIV-related PTSD is lacking. This article argues that the Ehlers & Clark (2000) cognitive model of PTSD provides a useful conceptual framework for understanding HIV-related PTSD in South Africa. The model emphasises the role of trauma appraisals in the development and maintenance of PTSD, which can also be usefully applied to some of the other psychological disorders associated with HIV infection. The model appears to fit some of the important research findings, and it offers insights into the relationships between HIV-related PTSD and other psychological disorders, HIV stigma, the high prevalence of non-HIV traumatic events, occasional problems with the delivery of antiretroviral drugs in the South African public health service, the unpredictable course of HIV illness, and the quality of HIV testing and counselling. Implications for individual treatment strategies and broader public health interventions are briefly discussed.

  15. Patient understanding of oral contraceptive pill instructions related to missed pills: a systematic review.

    Science.gov (United States)

    Zapata, Lauren B; Steenland, Maria W; Brahmi, Dalia; Marchbanks, Polly A; Curtis, Kathryn M

    2013-05-01

    Instructions on what to do after pills are missed are critical to reducing unintended pregnancies resulting from patient non-adherence to oral contraceptive (OC) regimens. Missed pill instructions have previously been criticized for being too complex, lacking a definition of what is meant by "missed pills," and for being confusing to women who may not know the estrogen content of their formulation. To help inform the development of missed pill guidance to be included in the forthcoming US Selected Practice Recommendations, the objective of this systematic review was to evaluate the evidence on patient understanding of missed pill instructions. We searched the PubMed database for peer-reviewed articles that examined patient understanding of OC pill instructions that were published in any language from inception of the database through March 2012. We included studies that examined women's knowledge and understanding of missed pill instructions after exposure to some written material (e.g., patient package insert, brochure), as well as studies that compared different types of missed pill instructions on women's comprehension. We used standard abstract forms and grading systems to summarize and assess the quality of the evidence. From 1620 articles, nine studies met our inclusion criteria. Evidence from one randomized controlled trial (RCT) and two descriptive studies found that more women knew what to do after missing 1 pill than after missing 2 or 3 pills (Level I, good, to Level II-3, poor), and two descriptive studies found that more women knew what to do after missing 2 pills than after missing 3 pills (Level II-3, fair). Data from two descriptive studies documented the difficulty women have understanding missed pill instructions contained in patient package inserts (Level II-3, poor), and evidence from two RCTs found that providing written brochures with information on missed pill instructions in addition to contraceptive counseling significantly improved

  16. Lay and health care professional understandings of self-management: A systematic review and narrative synthesis

    Directory of Open Access Journals (Sweden)

    Euan Sadler

    2014-08-01

    Full Text Available Objectives: Self-management is widely promoted but evidence of effectiveness is limited. Policy encourages health care professionals to support people with long-term conditions to learn self-management skills, yet little is known about the extent to which both parties share a common understanding of self-management. Thus, we compared health care professional and lay understandings of self-management of long-term conditions. Methods: Systematic review and narrative synthesis of qualitative studies identified from relevant electronic databases, hand-searching of references lists, citation tracking and recommendations by experts. Results: In total, 55 studies were included and quality was assessed using a brief quality assessment tool. Three conceptual themes, each with two subthemes were generated: traditional and shifting models of the professional–patient relationship (self-management as a tool to promote compliance; different expectations of responsibility; quality of relationship between health care professional and lay person (self-management as a collaborative partnership; self-management as tailored support and putting self-management into everyday practice (the lived experience of self-management; self-management as a social practice. Conclusion: Self-management was conceptualised by health care professionals as incorporating both a biomedical model of compliance and individual responsibility. Lay people understood self-management in wider terms, reflecting biomedical, psychological and social domains and different expectations of responsibility. In different ways, both deviated from the dominant model of self-management underpinned by the concept of self-efficacy. Different understandings help to explain how self-management is practised and may help to account for limited evidence of effectiveness of self-management interventions.

  17. Review of access, licenses and understandability of open datasets used in hydrology research

    Science.gov (United States)

    Falkenroth, Esa; Arheimer, Berit; Lagerbäck Adolphi, Emma

    2015-04-01

    The amount of open data available for hydrology research is continually growing. In the EU-funded project SWITCH-ON (Sharing Water-related Information to Tackle Changes in the Hydrosphere - for Operational Needs), we are addressing water concerns by exploring and exploiting the untapped potential of these new open data. This work is enabled by many ongoing efforts to facilitate the use of open data. For instance, a number of portals (such as the GEOSS Portal and the INSPIRE community geoportal) provide the means to search for such open data sets and open spatial data services. However, in general, the systematic use of available open data is still fairly uncommon in hydrology research. Factors that limits (re)usability of a data set include: (1) accessibility, (2) understandability and (3) licences. If you cannot access the data set, you cannot use if for research. If you cannot understand the data set you cannot use it for research. Finally, if you are not permitted to use the data, you cannot use it for research. Early on in the project, we sent out a questionnaire to our research partners (SMHI, Universita di Bologna, University of Bristol, Technische Universiteit Delft and Technische Universitaet Wien) to find out what data sets they were planning to use in their experiments. The result was a comprehensive list of useful open data sets. Later, this list of data sets was extended with additional information on data sets for planned commercial water-information products and services. With the list of 50 common data sets as a starting point, we reviewed issues related to access, understandability and licence conditions. Regarding access to data sets, a majority of data sets were available through direct internet download via some well-known transfer protocol such as ftp or http. However, several data sets were found to be inaccessible due to server downtime, incorrect links or problems with the host database management system. One possible explanation for this

  18. Composite sorbents of inorganic ion-exchangers and polyacrylonitrile binding matrix. Methods of modification of properties of inorganic ion-exchangers for application in column packed beds

    International Nuclear Information System (INIS)

    Sebesta, F.

    1997-01-01

    Methods of preparation of granules of inorganic ion exchangers as well as methods for improvement of granular strength of these materials are reviewed. The resulting ion exchangers are classified in three groups - 'intrinsic', supported and composite ion exchangers. Their properties are compared and possibilities of their technological application are evaluated. A new method of preparation of inorganic-organic composite sorbents of inorganic ion-exchangers and polyacrylonitrile binding matrix is described, advantages and disadvantages of such sorbents are discussed. Proposed fields of application include tratment of liquid radioactive and/or hazardous wastes, decontamination of natural water as well as analytical applications. (author)

  19. Deep Bed Iodine Sorbent Testing FY 2011 Report

    International Nuclear Information System (INIS)

    Soelberg, Nick; Watson, Tony

    2011-01-01

    Nuclear fission results in the production of fission products (FPs) and activation products that increasingly interfere with the fission process as their concentrations increase. Some of these fission and activation products tend to evolve in gaseous species during used nuclear fuel reprocessing. Analyses have shown that I129, due to its radioactivity, high potential mobility in the environment, and high longevity (half life of 15.7 million years), can require control efficiencies of up to 1,000x or higher to meet regulatory emission limits. Deep-bed iodine sorption testing has been done to evaluate the performance of solid sorbents for capturing iodine in off-gas streams from nuclear fuel reprocessing plants. The objectives of the FY 2011 deep bed iodine sorbent testing are: (1) Evaluate sorbents for iodine capture under various conditions of gas compositions and operating temperature (determine sorption efficiencies, capacities, and mass transfer zone depths); and (2) Generate data for dynamic iodine sorption modeling. Three tests performed this fiscal year on silver zeolite light phase (AgZ-LP) sorbent are reported here. Additional tests are still in progress and can be reported in a revision of this report or a future report. Testing was somewhat delayed and limited this year due to initial activities to address some questions of prior testing, and due to a period of maintenance for the on-line GC. Each test consisted of (a) flowing a synthetic blend of gases designed to be similar to an aqueous dissolver off-gas stream over the sorbent contained in three separate bed segments in series, (b) measuring each bed inlet and outlet gas concentrations of iodine and methyl iodide (the two surrogates of iodine gas species considered most representative of iodine species expected in dissolver off-gas), (c) operating for a long enough time to achieve breakthrough of the iodine species from at least one (preferably the first two) bed segments, and (d) post-test purging

  20. Understanding effects in reviews of implementation interventions using the Theoretical Domains Framework.

    Science.gov (United States)

    Little, Elizabeth A; Presseau, Justin; Eccles, Martin P

    2015-06-17

    Behavioural theory can be used to better understand the effects of behaviour change interventions targeting healthcare professional behaviour to improve quality of care. However, the explicit use of theory is rarely reported despite interventions inevitably involving at least an implicit idea of what factors to target to implement change. There is a quality of care gap in the post-fracture investigation (bone mineral density (BMD) scanning) and management (bisphosphonate prescription) of patients at risk of osteoporosis. We aimed to use the Theoretical Domains Framework (TDF) within a systematic review of interventions to improve quality of care in post-fracture investigation. Our objectives were to explore which theoretical factors the interventions in the review may have been targeting and how this might be related to the size of the effect on rates of BMD scanning and osteoporosis treatment with bisphosphonate medication. A behavioural scientist and a clinician independently coded TDF domains in intervention and control groups. Quantitative analyses explored the relationship between intervention effect size and total number of domains targeted, and as number of different domains targeted. Nine randomised controlled trials (RCTs) (10 interventions) were analysed. The five theoretical domains most frequently coded as being targeted by the interventions in the review included "memory, attention and decision processes", "knowledge", "environmental context and resources", "social influences" and "beliefs about consequences". Each intervention targeted a combination of at least four of these five domains. Analyses identified an inverse relationship between both number of times and number of different domains coded and the effect size for BMD scanning but not for bisphosphonate prescription, suggesting that the more domains the intervention targeted, the lower the observed effect size. When explicit use of theory to inform interventions is absent, it is possible to

  1. Characterization of calcium carbonate sorbent particle in furnace environment

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kang Soo [Aerosol and Particle Technology Laboratory, Department of Mechanical Engineering, KAIST 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 (Korea, Republic of); Jung, Jae Hee [Environment Sensor System Research Center, KIST 39-1 Hawolgok-dong, Seongbuk-gu, Seoul, 136-791 (Korea, Republic of); Keel, Sang In; Yun, Jin Han; Min, Tai Jin [Environmental Systems Research Division, KIMM 104 Sinseongno, Yuseong-gu, Daejeon, 305-343 (Korea, Republic of); Kim, Sang Soo, E-mail: sskim@kaist.ac.kr [Aerosol and Particle Technology Laboratory, Department of Mechanical Engineering, KAIST 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 (Korea, Republic of)

    2012-07-01

    The oxy-fuel combustion system is a promising technology to control CO{sub 2} and NO{sub X} emissions. Furthermore, sulfation reaction mechanism under CO{sub 2}-rich atmospheric condition in a furnace may lead to in-furnace desulfurization. In the present study, we evaluated characteristics of calcium carbonate (CaCO{sub 3}) sorbent particles under different atmospheric conditions. To examine the physical/chemical characteristics of CaCO{sub 3}, which is used as a sorbent particle for in-furnace desulfurization in the oxy-fuel combustion system, they were injected into high temperature drop tube furnace (DTF). Experiments were conducted at varying temperatures, residence times, and atmospheric conditions in a reactor. To evaluate the aerosolizing characteristics of the CaCO{sub 3} sorbent particle, changes in the size distribution and total particle concentration between the DTF inlet and outlet were measured. Structural changes (e.g., porosity, grain size, and morphology) of the calcined sorbent particles were estimated by BET/BJH, XRD, and SEM analyses. It was shown that sorbent particles rapidly calcined and sintered in the air atmosphere, whereas calcination was delayed in the CO{sub 2} atmosphere due to the higher CO{sub 2} partial pressure. Instead, the sintering effect was dominant in the CO{sub 2} atmosphere early in the reaction. Based on the SEM images, it was shown that the reactions of sorbent particles could be explained as a grain-subgrain structure model in both the air and CO{sub 2} atmospheres.

  2. Sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides

    Directory of Open Access Journals (Sweden)

    R.V. Smotraiev

    2016-05-01

    Full Text Available The actual problem of water supply in the world and in Ukraine, in particular, is a high level of pollution in water resources and an insufficient level of drinking water purification. With industrial wastewater, a significant amount of pollutants falls into water bodies, including suspended particles, sulfates, iron compounds, heavy metals, etc. Aim: The aim of this work is to determine the impact of aluminum and manganese ions additives on surface and sorption properties of zirconium oxyhydroxide based sorbents during their production process. Materials and Methods: The sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides were prepared by sol-gel method during the hydrolysis of metal chlorides (zirconium oxychloride ZrOCl2, aluminum chloride AlCl3 and manganese chloride MnCl2 with carbamide. Results: The surface and sorption properties of sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides were investigated. X-ray amorphous structure and evolved hydroxyl-hydrate cover mainly characterize the obtained xerogels. The composite sorbents based on xerogels of zirconium oxyhydroxide doped with aluminum oxyhydroxide (aS = 537 m2/g and manganese oxyhydroxide (aS = 356 m2/g have more developed specific surface area than single-component xerogels of zirconium oxyhydroxide (aS = 236 m2/g and aluminum oxyhydroxide (aS = 327 m2/g. The sorbent based on the xerogel of zirconium and manganese oxyhydroxides have the maximum SO42--ions sorption capacity. It absorbs 1.5 times more SO42–-ions than the industrial anion exchanger AN-221. The sorbents based on xerogels of zirconium oxyhydroxide has the sorption capacity of Fe3+-ions that is 1.5…2 times greater than the capacity of the industrial cation exchanger KU-2-8. The Na+-ions absorption capacity is 1.47…1.56 mmol/g for each sorbent. Conclusions: Based on these data it can be concluded that the proposed method is effective for sorbents production based on

  3. Itaconic acid based potential sorbent for uranium recovery

    International Nuclear Information System (INIS)

    Kalyan, Y.; Naidu, G.R.K.; Das, Sadananda; Pandey, A.K.; Reddy, A.V.R.

    2010-01-01

    Cross-linked hydrogels and adsorptive membranes containing Itaconic acid, Acrylamide, Penta erythritol tetra acrylate and α, α-dimethyl- α-phenyl aceto phenone were prepared by UV-initiated bulk polymerization. These hydrogels and adsorptive membranes were characterized for pH uptake, sorption and desorption kinetics and selectivity towards uranium. The sorption ability of the sorbents towards uranyl ion was thoroughly examined. The developed itaconic acid based sorbents were evaluated for the recovery of uranium from lean sources like sea water. (author)

  4. Bench-scale studies on capture of mercury on mineral non-carbon based sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yang [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion; Utah Univ., Salt Lake City, UT (United States). Dept. of Chemical Engineering; Wendt, Jost O.L. [Utah Univ., Salt Lake City, UT (United States). Dept. of Chemical Engineering; Zhang, Junying; Zheng, Chuguang [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion

    2013-07-01

    A new high-temperature, mineral non-carbon based dispersed sorbent derived from paper recycling products has been shown to capture mercury at high temperatures in excess of 600 C. The sorbent is consisted of kaolinite/calcite/lime mixtures. Experiments have been conducted on chemi-sorption of elemental mercury in air on a packed bed. The sorption occurs at temperatures between 600 and 1,100 C and requires activation of the minerals contained within the sorbents. Mercury capture is dominated by temperature and capture on sorbents over long time scales. The capture shows a maximum effectiveness at 1,000 C and increases monotonically with temperature. The presence of oxygen is also the required. Freshly activated sorbent is the most effective, and deactivation of sorbents occurs at high temperatures with long pre-exposure times. This activation is suspected to involve a solid-solid reaction between intimately mixed calcium oxide and silica that are both contained within the sorbent. Deactivation occurs at temperatures higher than 1,000 C, and this is due to melting of the substrate and pore closure. The situation in packed beds is complicated because the bed also shrinks, thus allowing channeling and by-passing, and consequent ambiguities in determining sorbent saturation. Sorbent A had significantly greater capacity for mercury sorption than did Sorbent B, for all temperatures and exposure time examined. The effect of SiO{sub 2} on poor Sorbent B is much larger than sorbent A.

  5. Understanding how environmental enhancement and conservation activities may benefit health and wellbeing: a systematic review.

    Science.gov (United States)

    Lovell, Rebecca; Husk, Kerryn; Cooper, Chris; Stahl-Timmins, Will; Garside, Ruth

    2015-09-07

    Action taken to enhance or conserve outdoor environments may benefit health and wellbeing through the process of participation but also through improving the environment. There is interest, amongst both health and environmental organisations, in using such activities as health promotion interventions. The objective of this systematic review was to investigate the health and wellbeing impacts of participation in environmental enhancement and conservation activities and to understand how these activities may be beneficial, to whom and in what circumstances or contexts. A theory-led mixed-method systematic review was used to assess evidence of effect and to identify pathways to change (protocol: http://onlinelibrary.wiley.com/doi/ 10.1002/14651858.CD010351/full ). Due to the multi-disciplinary, dispersed and disparate body of evidence an extensive multi-stage search strategy was devised and undertaken. Twenty-seven databases and multiple sources of grey literature were searched and over 200 relevant organisations were contacted. The heterogenous evidence was synthesised using a narrative approach and a conceptual model was developed to illustrate the mechanisms of effect. Due to the limited nature of the evidence additional higher order evidence was sought to assess the plausibility of the proposed mechanisms of effect through which health and wellbeing may accrue. The majority of the quantitative evidence (13 studies; all poor quality and lower-order study designs) was inconclusive, though a small number of positive and negative associations were observed. The qualitative evidence (13 studies; 10 poor quality, 3 good) indicated that the activities were perceived to have value to health and wellbeing through a number of key mechanisms; including exposure to natural environments, achievement, enjoyment and social contact. Additional high level evidence indicated that these pathways were plausible. Despite interest in the use of environmental enhancement activities as a

  6. Neisseria gonorrhoeae molecular typing for understanding sexual networks and antimicrobial resistance transmission: A systematic review.

    Science.gov (United States)

    Town, Katy; Bolt, Hikaru; Croxford, Sara; Cole, Michelle; Harris, Simon; Field, Nigel; Hughes, Gwenda

    2018-06-01

    Neisseria gonorrhoeae (NG) is a significant global public health concern due to rising diagnoses rates and antimicrobial resistance. Molecular combined with epidemiological data have been used to understand the distribution and spread of NG, as well as relationships between cases in sexual networks, but the public health value gained from these studies is unclear. We conducted a systematic review to examine how molecular epidemiological studies have informed understanding of sexual networks and NG transmission, and subsequent public health interventions. Five research databases were systematically searched up to 31st March 2017 for studies that used sequence-based DNA typing methods, including whole genome sequencing, and linked molecular data to patient-level epidemiological data. Data were extracted and summarised to identify common themes. Of the 49 studies included, 82% used NG Multi-antigen Sequence Typing. Gender and sexual orientation were commonly used to characterise sexual networks that were inferred using molecular clusters; clusters predominantly of one patient group often contained a small number of isolates from other patient groups. Suggested public health applications included using these data to target interventions at specific populations, confirm outbreaks, and inform partner management, but these were mainly untested. Combining molecular and epidemiological data has provided insight into sexual mixing patterns, and dissemination of NG, but few studies have applied these findings to design or evaluate public health interventions. Future studies should focus on the application of molecular epidemiology in public health practice to provide evidence for how to prevent and control NG. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Understanding the use of geographical information systems (GIS) in health informatics research: A review.

    Science.gov (United States)

    Shaw, Nicola; McGuire, Suzanne

    2017-06-23

    The purpose of this literature review is to understand geographical information systems (GIS) and how they can be applied to public health informatics, medical informatics, and epidemiology. Relevant papers that reflected the use of geographical information systems (GIS) in health research were identified from four academic databases: Academic Search Complete, BioMed Central, PubMed Central, and Scholars Portal, as well as Google Scholar. The search strategy used was to identify articles with "geographic information systems", "GIS", "public health", "medical informatics", "epidemiology", and "health geography" as main subject headings or text words in titles and abstracts. Papers published between 1997 and 2014 were considered and a total of 39 articles were included to inform the authors on the use of GIS technologies in health informatics research. The main applications of GIS in health informatics and epidemiology include disease surveillance, health risk analysis, health access and planning, and community health profiling. GIS technologies can significantly improve quality and efficiency in health research as substantial connections can be made between a population's health and their geographical location. Gains in health informatics can be made when GIS are applied through research, however, improvements need to occur in the quantity and quality of data input for these systems to ensure better geographical health maps are used so that proper conclusions between public health and environmental factors may be made.

  8. Understanding critical factors for the quality and shelf-life of MAP fresh meat: a review.

    Science.gov (United States)

    Singh, Preeti; Wani, Ali Abas; Saengerlaub, Sven; Langowski, Horst-Christian

    2011-02-01

    Due to increased demands for greater stringency in relation to hygiene and safety issues associated with fresh food products, coupled with ever-increasing demands by retailers for cost-effective extensions to product shelf-lives and the requirement to meet consumer expectations in relation to convenience and quality, the food packaging industry has rapidly developed to meet and satisfy expectations. One of the areas of research that has shown promise, and had success, is modified atmosphere packaging (MAP). The success of MAP-fresh meat depends on many factors including good initial product quality, good hygiene from the source plants, correct packaging material selection, the appropriate gas mix for the product, reliable packaging equipment, and maintenance of controlled temperatures and humidity levels. Advances in plastic materials and equipment have propelled advances in MAP, but other technological and logistical considerations are needed for successful MAP systems for raw chilled meat. Although several parameters critical for the quality of MA packed meat have been studied and each found to be crucial, understanding of the interactions between the parameters is needed. This review was undertaken to present the most comprehensive and current overview of the widely available, scattered information about the various integrated critical factors responsible for the quality and shelf life of MA packed meat with an interest to stimulate further research to optimize different quality parameters.

  9. Understanding recall rates in screening mammography: A conceptual framework review of the literature

    International Nuclear Information System (INIS)

    Mohd Norsuddin, N.; Reed, W.; Mello-Thoms, C.; Lewis, S.J.

    2015-01-01

    Recall rates are one of the performance measures used to evaluate the effectiveness of mammography screening programs. There is conflicting evidence regarding the link between recall rates and cancer detection rates and a variety of differing recall rates exist between countries and readers. This variability in recall rates may have important clinical and economic implications such as unnecessary follow-up procedures, additional costs to the health care system and psychological effects for the women themselves associated with false-positive mammograms results. In order to reduce the impact of false positive recall rates in screening mammography, it is essential for all multidisciplinary health care providers, especially those in medical imaging, to fully understand the factors that may contribute and affect recall rates. The multifactorial nature of recall rates is explored in this paper through the construction of a conceptual map based on a review of the current literature. - Highlights: • Recall rates vary across countries and readers and for initial and subsequent screens. • Falsely recalling women has important clinical, cost and psycho-social implications. • Imaging technology, readers' expertise and patient presentation affect recall rates. • Higher recall rates do not translate into improved sensitivity at higher thresholds. • Multidisciplinary approaches to reduce recall rates may improve women experiences.

  10. Review of the Scientific Understanding of Radioactive Waste at the U.S. DOE Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Reid A.; Buck, Edgar C.; Chun, Jaehun; Daniel, Richard C.; Herting, Daniel L. [Washington River Protection Solutions, Richland, Washington 99354, United States; Ilton, Eugene S.; Lumetta, Gregg J.; Clark, Sue B. [Chemistry

    2018-01-02

    This paper reviews the origin and chemical and rheological complexity of radioactive waste at the U.S. Department of Energy’s Hanford Site. The waste, stored in underground tanks, was generated via three distinct processes over decades of plutonium extraction operations. Although close records were kept of original waste disposition, tank-to-tank transfers and conditions that impede equilibrium complicate our understanding of the chemistry, phase composition, and rheology of the waste. Tank waste slurries comprise particles and aggregates from nano to micron scales, with varying densities, morphologies, heterogeneous compositions, and complicated responses to flow regimes and process conditions. Further, remnant or changing radiation fields may affect the stability and rheology of the waste. These conditions pose challenges for transport through conduits or pipes to treatment plants for vitrification. Additionally, recalcitrant boehmite degrades glass quality and must be reduced prior to vitrification, but dissolves much more slowly than predicted given surface normalized rates. Existing empirical models based on ex situ experiments and observations lack true predictive capabilities. Recent advances in in situ microscopy, aberration corrected TEM, theoretical modeling across scales, and experimental methods for probing the physics and chemistry at mineral-fluid and mineral-mineral interfaces are being implemented to build robustly predictive physics-based models.

  11. Do brain image databanks support understanding of normal ageing brain structure? A systematic review

    International Nuclear Information System (INIS)

    Dickie, David Alexander; Job, Dominic E.; Wardlaw, Joanna M.; Poole, Ian; Ahearn, Trevor S.; Staff, Roger T.; Murray, Alison D.

    2012-01-01

    To document accessible magnetic resonance (MR) brain images, metadata and statistical results from normal older subjects that may be used to improve diagnoses of dementia. We systematically reviewed published brain image databanks (print literature and Internet) concerned with normal ageing brain structure. From nine eligible databanks, there appeared to be 944 normal subjects aged ≥60 years. However, many subjects were in more than one databank and not all were fully representative of normal ageing clinical characteristics. Therefore, there were approximately 343 subjects aged ≥60 years with metadata representative of normal ageing, but only 98 subjects were openly accessible. No databank had the range of MR image sequences, e.g. T2*, fluid-attenuated inversion recovery (FLAIR), required to effectively characterise the features of brain ageing. No databank supported random subject retrieval; therefore, manual selection bias and errors may occur in studies that use these subjects as controls. Finally, no databank stored results from statistical analyses of its brain image and metadata that may be validated with analyses of further data. Brain image databanks require open access, more subjects, metadata, MR image sequences, searchability and statistical results to improve understanding of normal ageing brain structure and diagnoses of dementia. (orig.)

  12. Review: Animal model and the current understanding of molecule dynamics of adipogenesis.

    Science.gov (United States)

    Campos, C F; Duarte, M S; Guimarães, S E F; Verardo, L L; Wei, S; Du, M; Jiang, Z; Bergen, W G; Hausman, G J; Fernyhough-Culver, M; Albrecht, E; Dodson, M V

    2016-06-01

    Among several potential animal models that can be used for adipogenic studies, Wagyu cattle is the one that presents unique molecular mechanisms underlying the deposit of substantial amounts of intramuscular fat. As such, this review is focused on current knowledge of such mechanisms related to adipose tissue deposition using Wagyu cattle as model. So abundant is the lipid accumulation in the skeletal muscles of these animals that in many cases, the muscle cross-sectional area appears more white (adipose tissue) than red (muscle fibers). This enhanced marbling accumulation is morphologically similar to that seen in numerous skeletal muscle dysfunctions, disease states and myopathies; this might indicate cross-similar mechanisms between such dysfunctions and fat deposition in Wagyu breed. Animal models can be used not only for a better understanding of fat deposition in livestock, but also as models to an increased comprehension on molecular mechanisms behind human conditions. This revision underlies some of the complex molecular processes of fat deposition in animals.

  13. The Understanding of Peace among Children and Adolescents: A Critical Review of Research

    Directory of Open Access Journals (Sweden)

    Ron Smith

    2006-05-01

    Full Text Available Contextualisation Despite the existence in Northern Ireland of an internationally endorsed Peace Process (the 1998 Good Friday or Belfast Agreement, the need for education to play its part in developing a new peace culture and peace consciousness remains as important as ever. In December 1998, the Education Minister established a working group concerned with the promotion of tolerance in schools. The report of this group recommended that there needed to be greater encouragement to regard the development of respect for diversity as a core rather than peripheral element of the school curriculum (DENI 2000. However, earlier research suggested that the received discourses and assumptions about school effectiveness and school improvement were inappropriate to meeting the challenges of improving school effectiveness for peace within a conflicted society (see, Smith 2001 a; 2001 b. This research confirmed that there was a pervasive "culture of silence" within schools with regard to open discussion on the causes and consequences of social division. There were also other silences and gaps in the story forms available to teachers within schools. When, for example, it came to having a say or being allowed to air their views on issues of relevance to school-based community relations policy and practice, the voice of students and parents were mostly silenced, disqualified or subjugated. Consequently, I decided to examine the theme of school improvement for peace from a Narrative psychology perspective. That is, from a perspective which gives a central role to the storied nature of human conduct. This stance is a special case of the wider perspective called social constructionism (Wagner and Watkins, forthcoming. A critical review of relevant extant literatures, including the developmental literature on children's and young peoples' understanding of peace, strengthened my view that new paradigm methodologies and methods were required to investigate and

  14. Sorption of europium (3) by polymer sorbents with grafted heterocyclic nitrogen-containing groupings

    International Nuclear Information System (INIS)

    Bel'tyukova, S.V.; Kravchenko, T.B.; Balamtsarashvili, G.M.; Roska, A.S.

    1990-01-01

    On polymer sorbents (copolymer of styrene-divinylbenzene) with grafted heterocyclic nitrogen-containing functional groupings of tetrazole, triazole and imidazole (sorbents 1,2,3, respectively). It is stated that europium sorption takes place from neutral solutions in presence of organic solvents. Luminescent properties of europium on sorbent are used to develope methods of its determination in high purity lanthanide and yttrium oxides. Europium determination limits consist 7.5·10 -5 μg/ml on 1 and 3 sorbents and 1.5·10 -4 μg/ml on sorbent 2, S p value is 0.089 and 0.075, respectivaly

  15. Novel composite sorbent AAm/MA hydrogels containing starch and ...

    Indian Academy of Sciences (India)

    A novel polymer/clay composite sorbent based on acrylamide/maleic acid, starch and clay such as kaolin was synthesized with free radical solution polymerization by using ammonium persulfate/,,','-tetramethylethylenediamine as redox initiating pair in the presence of poly(ethylene glycol)diacrylate as a crosslinker.

  16. New Composite Sorbents for Caesium and Strontium Ions Sorption

    Directory of Open Access Journals (Sweden)

    Mykola Kartel

    2017-06-01

    Full Text Available Composite lignocellulose-inorganic sorbents derived from plant residues of agriculture and food industry, modified with ferrocyanides of d-metals and hydrated antimony pentoxide were prepared. Caesium and strontium ions removal from water was tested by radiotracer method. Sorption of heavy metal ions, methylene blue, gelatin, vitamin B12 was also studied.

  17. Comments on "Ceria-Zirconia High-Temperature Desulfurization Sorbents".

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Trnka, Otakar

    2006-01-01

    Roč. 45, č. 4 (2006), s. 1548-1549 ISSN 0888-5885 Institutional research plan: CEZ:AV0Z40720504 Keywords : hydrogen sulfide * desulfurization * cerium sorbent Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.518, year: 2006

  18. Natural sorbents for decontamination of objects of urban territories

    International Nuclear Information System (INIS)

    Movchan, N.; Fedorenko, Yu.; Zlobenko, B.; Spigoun, A.

    1996-01-01

    This paper gives an information about the use of film coverings, based on natural sorbents, in decontamination of buildings, contaminated after the Chernobyl accident. This method has incontrovertible advantages in the beginning period after the accident and can be used for cleaning considerable areas of urban territories

  19. Core-in-shell sorbent for hot coal gas desulfurization

    Science.gov (United States)

    Wheelock, Thomas D.; Akiti, Jr., Tetteh T.

    2004-02-10

    A core-in-shell sorbent is described herein. The core is reactive to the compounds of interest, and is preferably calcium-based, such as limestone for hot gas desulfurization. The shell is a porous protective layer, preferably inert, which allows the reactive core to remove the desired compounds while maintaining the desired physical characteristics to withstand the conditions of use.

  20. MERCURY CONTROL WITH CALCIUM-BASED SORBENTS AND OXIDIZING AGENTS

    Energy Technology Data Exchange (ETDEWEB)

    Thomas K. Gale

    2002-06-01

    The initial tasks of this DOE funded project to investigate mercury removal by calcium-based sorbents have been completed, and initial testing results have been obtained. Mercury monitoring capabilities have been obtained and validated. An approximately 1MW (3.4 Mbtu/hr) Combustion Research Facility at Southern Research Institute was used to perform pilot-scale investigations of mercury sorbents, under conditions representative of full-scale boilers. The initial results of ARCADIS G&M proprietary sorbents, showed ineffective removal of either elemental or oxidized mercury. Benchscale tests are currently underway to ascertain the importance of differences between benchscale and pilot-scale experiments. An investigation of mercury-capture temperature dependence using common sorbents has also begun. Ordinary hydrated lime removed 80 to 90% of the mercury from the flue gas, regardless of the temperature of injection. High temperature injection of hydrated lime simultaneously captured SO{sub 2} at high temperatures and Hg at low temperatures, without any deleterious effects on mercury speciation. Future work will explore alternative methods of oxidizing elemental mercury.

  1. An illustrative review to understand and manage metal-induced artifacts in musculoskeletal MRI: a primer and updates

    Energy Technology Data Exchange (ETDEWEB)

    Dillenseger, J.P.; Choquet, P.; Goetz, C.; Bierry, G. [University Hospital of Strasbourg, Medical Imaging Department, Strasbourg (France); Icube, CNRS, University of Strasbourg, Strasbourg (France); University of Strasbourg, Translational Medicine Research Federation, Strasbourg Medical School, Strasbourg (France); Moliere, S. [University Hospital of Strasbourg, Medical Imaging Department, Strasbourg (France); Ehlinger, M. [Icube, CNRS, University of Strasbourg, Strasbourg (France); University of Strasbourg, Translational Medicine Research Federation, Strasbourg Medical School, Strasbourg (France); University Hospital of Strasbourg, Department of Orthopedic Surgery, Strasbourg (France)

    2016-05-15

    This article reviews and explains the basic physical principles of metal-induced MRI artifacts, describes simple ways to reduce them, and presents specific reduction solutions. Artifacts include signal loss, pile-up artifacts, geometric distortion, and failure of fat suppression. Their nature and origins are reviewed and explained though schematic representations that ease the understanding. Then, optimization of simple acquisition parameters is detailed. Lastly, dedicated sequences and options specifically developed to reduce metal artifacts (VAT, SEMAC, and MAVRIC) are explained. (orig.)

  2. Current understanding of the driving mechanisms for spatiotemporal variations of atmospheric speciated mercury: a review

    Directory of Open Access Journals (Sweden)

    H. Mao

    2016-10-01

    Full Text Available Atmospheric mercury (Hg is a global pollutant and thought to be the main source of mercury in oceanic and remote terrestrial systems, where it becomes methylated and bioavailable; hence, atmospheric mercury pollution has global consequences for both human and ecosystem health. Understanding of spatial and temporal variations of atmospheric speciated mercury can advance our knowledge of mercury cycling in various environments. This review summarized spatiotemporal variations of total gaseous mercury or gaseous elemental mercury (TGM/GEM, gaseous oxidized mercury (GOM, and particulate-bound mercury (PBM in various environments including oceans, continents, high elevation, the free troposphere, and low to high latitudes. In the marine boundary layer (MBL, the oxidation of GEM was generally thought to drive the diurnal and seasonal variations of TGM/GEM and GOM in most oceanic regions, leading to lower GEM and higher GOM from noon to afternoon and higher GEM during winter and higher GOM during spring–summer. At continental sites, the driving mechanisms of TGM/GEM diurnal patterns included surface and local emissions, boundary layer dynamics, GEM oxidation, and for high-elevation sites mountain–valley winds, while oxidation of GEM and entrainment of free tropospheric air appeared to control the diurnal patterns of GOM. No pronounced diurnal variation was found for Tekran measured PBM at MBL and continental sites. Seasonal variations in TGM/GEM at continental sites were attributed to increased winter combustion and summertime surface emissions, and monsoons in Asia, while those in GOM were controlled by GEM oxidation, free tropospheric transport, anthropogenic emissions, and wet deposition. Increased PBM at continental sites during winter was primarily due to local/regional coal and wood combustion emissions. Long-term TGM measurements from the MBL and continental sites indicated an overall declining trend. Limited measurements suggested TGM

  3. Current understanding of the driving mechanisms for spatiotemporal variations of atmospheric speciated mercury: a review

    Science.gov (United States)

    Mao, Huiting; Cheng, Irene; Zhang, Leiming

    2016-10-01

    Atmospheric mercury (Hg) is a global pollutant and thought to be the main source of mercury in oceanic and remote terrestrial systems, where it becomes methylated and bioavailable; hence, atmospheric mercury pollution has global consequences for both human and ecosystem health. Understanding of spatial and temporal variations of atmospheric speciated mercury can advance our knowledge of mercury cycling in various environments. This review summarized spatiotemporal variations of total gaseous mercury or gaseous elemental mercury (TGM/GEM), gaseous oxidized mercury (GOM), and particulate-bound mercury (PBM) in various environments including oceans, continents, high elevation, the free troposphere, and low to high latitudes. In the marine boundary layer (MBL), the oxidation of GEM was generally thought to drive the diurnal and seasonal variations of TGM/GEM and GOM in most oceanic regions, leading to lower GEM and higher GOM from noon to afternoon and higher GEM during winter and higher GOM during spring-summer. At continental sites, the driving mechanisms of TGM/GEM diurnal patterns included surface and local emissions, boundary layer dynamics, GEM oxidation, and for high-elevation sites mountain-valley winds, while oxidation of GEM and entrainment of free tropospheric air appeared to control the diurnal patterns of GOM. No pronounced diurnal variation was found for Tekran measured PBM at MBL and continental sites. Seasonal variations in TGM/GEM at continental sites were attributed to increased winter combustion and summertime surface emissions, and monsoons in Asia, while those in GOM were controlled by GEM oxidation, free tropospheric transport, anthropogenic emissions, and wet deposition. Increased PBM at continental sites during winter was primarily due to local/regional coal and wood combustion emissions. Long-term TGM measurements from the MBL and continental sites indicated an overall declining trend. Limited measurements suggested TGM/GEM increasing from the

  4. A review of recent developments in the understanding of transonic shock buffet

    Science.gov (United States)

    Giannelis, Nicholas F.; Vio, Gareth A.; Levinski, Oleg

    2017-07-01

    Within a narrow band of flight conditions in the transonic regime, interactions between shock-waves and intermittently separated shear layers result in large amplitude, self-sustained shock oscillations. This phenomenon, known as transonic shock buffet, limits the flight envelope and is detrimental to both platform handling quality and structural integrity. The severity of this instability has incited a plethora of research to ascertain an underlying physical mechanism, and yet, with over six decades of investigation, aspects of this complex phenomenon remain inexplicable. To promote continual progress in the understanding of transonic shock buffet, this review presents a consolidation of recent investigations in the field. The paper begins with a conspectus of the seminal literature on shock-induced separation and modes of shock oscillation. The currently prevailing theories for the governing physics of transonic shock buffet are then detailed. This is followed by an overview of computational studies exploring the phenomenon, where the results of simulation are shown to be highly sensitive to the specific numerical methods employed. Wind tunnel investigations on two-dimensional aerofoils at shock buffet conditions are then outlined and the importance of these experiments for the development of physical models stressed. Research considering dynamic structural interactions in the presence of shock buffet is also highlighted, with a particular emphasis on the emergence of a frequency synchronisation phenomenon. An overview of three-dimensional buffet is provided next, where investigations suggest the governing mechanism may differ significantly from that of two-dimensional sections. Subsequently, a number of buffet suppression technologies are described and their efficacy in mitigating shock oscillations is assessed. To conclude, recommendations for the direction of future research efforts are given.

  5. Understanding and Resolving Failures in Human-Robot Interaction: Literature Review and Model Development

    Directory of Open Access Journals (Sweden)

    Shanee Honig

    2018-06-01

    Full Text Available While substantial effort has been invested in making robots more reliable, experience demonstrates that robots operating in unstructured environments are often challenged by frequent failures. Despite this, robots have not yet reached a level of design that allows effective management of faulty or unexpected behavior by untrained users. To understand why this may be the case, an in-depth literature review was done to explore when people perceive and resolve robot failures, how robots communicate failure, how failures influence people's perceptions and feelings toward robots, and how these effects can be mitigated. Fifty-two studies were identified relating to communicating failures and their causes, the influence of failures on human-robot interaction (HRI, and mitigating failures. Since little research has been done on these topics within the HRI community, insights from the fields of human computer interaction (HCI, human factors engineering, cognitive engineering and experimental psychology are presented and discussed. Based on the literature, we developed a model of information processing for robotic failures (Robot Failure Human Information Processing, RF-HIP, that guides the discussion of our findings. The model describes the way people perceive, process, and act on failures in human robot interaction. The model includes three main parts: (1 communicating failures, (2 perception and comprehension of failures, and (3 solving failures. Each part contains several stages, all influenced by contextual considerations and mitigation strategies. Several gaps in the literature have become evident as a result of this evaluation. More focus has been given to technical failures than interaction failures. Few studies focused on human errors, on communicating failures, or the cognitive, psychological, and social determinants that impact the design of mitigation strategies. By providing the stages of human information processing, RF-HIP can be used as a

  6. Recent developments in the understanding of equatorial ionization anomaly: A review

    Science.gov (United States)

    Balan, N.; Souza, J.; Bailey, G. J.

    2018-06-01

    A brief review of the recent developments in the understanding of the equatorial plasma fountain (EPF) and equatorial ionization anomaly (EIA) under quiet and active conditions is presented. It is clarified that (1) the EPF is not upward ExB plasma drift at the equator followed by downward plasma diffusion, but it is field perpendicular ExB plasma drift and field-aligned plasma diffusion acting together all along the field lines at all altitudes and plasma flowing in the direction of the resultant. (2) The EIA is formed not from the accumulation of plasma at the crests but mainly from the removal of plasma from around the equator by the upward ExB drift with small accumulations when the crests are within approximately ±20° magnetic latitude. The accumulations reduce with increasing latitude and become zero by approximately ±25°. (3) An asymmetric neutral wind makes EPF and EIA asymmetric with stronger fountain and stronger crest usually occurring in opposite hemispheres especially at equinoxes when winter anomaly is absent. (4) During the early stages of daytime main phase of major geomagnetic storms, the plasma fountain becomes a super fountain and the EIA becomes strong not due to the eastward prompt penetration electric field (PPEF) alone but due to the combined effect of eastward PPEF and storm-time equatorward winds (SEW). (5) During the later stages of the storms when EIA gets inhibited a peak sometimes occurs around the equator not due to westward electric fields but mainly due to the convergence of plasma from both hemispheres due to SEW.

  7. Calcium oxide doped sorbents for CO{sub 2} uptake in the presence of SO{sub 2} at high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Lu, H.; Smirniotis, P.G. [University of Cincinnati, Cincinnati, OH (United States)

    2009-06-15

    There is an urgent need to understand sorbent tolerance for capturing carbon dioxide (CO{sub 2}) in the presence of sulfur dioxide (SO{sub 2}). Sulfur oxide is emitted together with CO{sub 2} from various combustion systems and can cause severe air pollution. In this study, the behavior of different dopants on the performance of calcium oxide (CaO) sorbent for capturing CO{sub 2} in the presence of SO{sub 2} was investigated. Three main sets of experiments were carried out to study carbonation and sulfation both separately and simultaneously using a thermogravimetric analyzer (TGA). The results show that SO{sub 2} reduced the capability of the sorbents for capturing CO{sub 2} because of the competition between carbonation and sulfation reactions. Formation of calcium carbonate (CaCO{sub 3}) and calcium sulfate (CaSO{sub 4}) took place upon carbonation and sulfation, respectively. Our TGA and X-ray photoelectron spectroscopy (XPS) results indicate that the carbonation is totally reversible, while this is not the case with the sulfation. The permanent residual weight gained by the sorbents during the course of sulfation is attributed to the irreversible formation of sulfate species, which is confirmed by both the TGA and XPS results. The Ce promoted CaO sorbent exhibits the best performance for CO{sub 2} capture and is the most SO{sub 2} tolerant sorbent. On the other hand, the Mn doped dopant has the strongest affinity for SO{sub 2}.

  8. Open data used in water sciences - Review of access, licenses and understandability

    Science.gov (United States)

    Falkenroth, Esa; Lagerbäck Adolphi, Emma; Arheimer, Berit

    2016-04-01

    . Understandability of the data sets: 13 major formats were found, but the major issues encountered were due to incomplete documentation or metadata and problems with decoding binary formats. Ideally, open data sets should be represented in well-known formats and they should be accompanied with sufficient documentation so the data set can be understood. The development efforts on Water ML and NETCDF and other standards could improve understandability of data sets over time but in this review, only a few data sets were provided in these formats. Instead, the majority of datasets were stored in various text-based or binary formats or even document-oriented formats such as PDF. Other disciplines such as meteorology have long-standing traditions of operational data exchange format whereas hydrology research is still quite fragmented and the data exchange is usually done on a case-by-case basis. With the increased sharing of open data there is a good chance the situation will improve for data sets used also in water sciences. License issue: Only 3% of the data is completely free to use, while 57% can be used for non-commercial purposes or research. A high number of datasets did not have a clear statement on terms of use and limitation for access. In most cases the provider could be contacted regarding licensing issues.

  9. IgE and the role of the Radio-Allergo-Sorbent Test (RAST)

    International Nuclear Information System (INIS)

    Grond, K.

    1976-01-01

    In 1966 a new immunoglobulin was found in persons with allergies and in non-typical myeloma proteins. Normally this immunoglobulin E is present only in nanogramms and rests with predilection on the membrane of mast-cells. There is a reaginic-anaphylactic reaction after re-exposure of antigens to the antigen-antibody reaction followed by denudation of mediators of the anaphylactic reaction. With the Radio-Immuno-Sorbent-Test (RIST) the IgE can be quantitatively determined. Elevated IgE-blood levels are typically found in atopic eczema. With the Radio-Allergo-Sorbent-Test (RAST) the allergen specific IgE can be defined. A conformity with appropriate patchtests can be achieved in 60-80% of the cases. In this review advantoses and problem of RIST- and RAST-diagnoses are described. RAST presents a valuable aid in diagnosis of allergies beeing not burdensome and risky, as it is easy to perform and bears no risk to the patients. At the present time, however, patch tests are necessary in the diagnosis of allergies. (orig.) [de

  10. Application potential of grapefruit peel as dye sorbent: Kinetics, equilibrium and mechanism of crystal violet adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Saeed, Asma, E-mail: asmadr@wol.net.pk [Environmental Biotechnology Group, Biotechnology and Food Research Centre, PCSIR Laboratories Complex, Ferozepur Road, Lahore 54600 (Pakistan); Sharif, Mehwish [School of Biological Sciences, University of the Punjab, Lahore 54590 (Pakistan); Iqbal, Muhammad [Environmental Biotechnology Group, Biotechnology and Food Research Centre, PCSIR Laboratories Complex, Ferozepur Road, Lahore 54600 (Pakistan)

    2010-07-15

    This study reports the sorption of crystal violet (CV) dye by grapefruit peel (GFP), which has application potential in the remediation of dye-contaminated wastewaters using a solid waste generated by the citrus fruit juice industry. Batch adsorption of CV was conducted to evaluate the effect of initial pH, contact time, temperature, initial dye concentration, GFP adsorbent dose, and removal of the adsorbate CV dye from aqueous solution to understand the mechanism of sorption involved. Sorption equilibrium reached rapidly with 96% CV removal in 60 min. Fit of the sorption experimental data was tested on the pseudo-first and pseudo-second-order kinetics mathematical equations, which was noted to follow the pseudo-second-order kinetics better, with coefficient of correlation {>=}0.992. The equilibrium process was well described by the Langmuir isotherm model, with maximum sorption capacity of 254.16 mg g{sup -1}. The GFP was regenerated using 1 M NaOH, with up to 98.25% recovery of CV and could be reused as a dye sorbent in repeated cycles. GFP was also shown to be highly effective in removing CV from aqueous solution in continuous-flow fixed-bed column reactors. The study shows that GFP has the potential of application as an efficient sorbent for the removal of CV from aqueous solutions.

  11. Application potential of grapefruit peel as dye sorbent: Kinetics, equilibrium and mechanism of crystal violet adsorption

    International Nuclear Information System (INIS)

    Saeed, Asma; Sharif, Mehwish; Iqbal, Muhammad

    2010-01-01

    This study reports the sorption of crystal violet (CV) dye by grapefruit peel (GFP), which has application potential in the remediation of dye-contaminated wastewaters using a solid waste generated by the citrus fruit juice industry. Batch adsorption of CV was conducted to evaluate the effect of initial pH, contact time, temperature, initial dye concentration, GFP adsorbent dose, and removal of the adsorbate CV dye from aqueous solution to understand the mechanism of sorption involved. Sorption equilibrium reached rapidly with 96% CV removal in 60 min. Fit of the sorption experimental data was tested on the pseudo-first and pseudo-second-order kinetics mathematical equations, which was noted to follow the pseudo-second-order kinetics better, with coefficient of correlation ≥0.992. The equilibrium process was well described by the Langmuir isotherm model, with maximum sorption capacity of 254.16 mg g -1 . The GFP was regenerated using 1 M NaOH, with up to 98.25% recovery of CV and could be reused as a dye sorbent in repeated cycles. GFP was also shown to be highly effective in removing CV from aqueous solution in continuous-flow fixed-bed column reactors. The study shows that GFP has the potential of application as an efficient sorbent for the removal of CV from aqueous solutions.

  12. Application potential of grapefruit peel as dye sorbent: kinetics, equilibrium and mechanism of crystal violet adsorption.

    Science.gov (United States)

    Saeed, Asma; Sharif, Mehwish; Iqbal, Muhammad

    2010-07-15

    This study reports the sorption of crystal violet (CV) dye by grapefruit peel (GFP), which has application potential in the remediation of dye-contaminated wastewaters using a solid waste generated by the citrus fruit juice industry. Batch adsorption of CV was conducted to evaluate the effect of initial pH, contact time, temperature, initial dye concentration, GFP adsorbent dose, and removal of the adsorbate CV dye from aqueous solution to understand the mechanism of sorption involved. Sorption equilibrium reached rapidly with 96% CV removal in 60 min. Fit of the sorption experimental data was tested on the pseudo-first and pseudo-second-order kinetics mathematical equations, which was noted to follow the pseudo-second-order kinetics better, with coefficient of correlation > or = 0.992. The equilibrium process was well described by the Langmuir isotherm model, with maximum sorption capacity of 254.16 mg g(-1). The GFP was regenerated using 1 M NaOH, with up to 98.25% recovery of CV and could be reused as a dye sorbent in repeated cycles. GFP was also shown to be highly effective in removing CV from aqueous solution in continuous-flow fixed-bed column reactors. The study shows that GFP has the potential of application as an efficient sorbent for the removal of CV from aqueous solutions. 2010 Elsevier B.V. All rights reserved.

  13. A Longitudinal Study of Decomposition Odour in Soil Using Sorbent Tubes and Solid Phase Microextraction

    Directory of Open Access Journals (Sweden)

    Katelynn A. Perrault

    2014-07-01

    Full Text Available Odour profiling of decomposed remains is important for understanding the mechanisms that cadaver dogs and forensically-relevant insects use to locate decomposed remains. The decomposition odour profile is complex and has been documented in outdoor terrestrial environments. The purpose of this study was to perform longitudinal analysis of the volatile organic compound (VOC profile in soils associated with decomposed remains across all stages of decomposition. Two VOC collection techniques (sorbent tubes and solid phase microextraction were used to collect a wider analyte range and to investigate differences in collection techniques. Pig carcasses were placed in an outdoor research facility in Australia to model the decomposition process and VOCs were collected intermittently over two months. VOCs of interest were identified over the duration of the trial, showing distinct trends in compound evolution and disappearance. The collection techniques were complementary, representing different subsets of VOCs from the overall profile. Sorbent tubes collected more decomposition-specific VOCs and these compounds were more effective at characterising the matrix over an extended period. Using both collection techniques improves the likelihood of identifying the complete VOC profile of decomposition odour. Such information is important for the search and recovery of victim remains in various stages of decomposition.

  14. Understanding the Relationship between Teachers' Pedagogical Beliefs and Technology Use in Education: A Systematic Review of Qualitative Evidence

    Science.gov (United States)

    Tondeur, Jo; van Braak, Johan; Ertmer, Peggy A.; Ottenbreit-Leftwich, Anne

    2017-01-01

    This review was designed to further our understanding of the link between teachers' pedagogical beliefs and their educational uses of technology. The synthesis of qualitative findings integrates the available evidence about this relationship with the ultimate goal being to facilitate the integration of technology in education. A meta-aggregative…

  15. Carbon Dioxide Capture from Flue Gas Using Dry Regenerable Sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Thomas Nelson; David Green; Paul Box; Raghubir Gupta; Gennar Henningsen

    2007-06-30

    Regenerable sorbents based on sodium carbonate (Na{sub 2}CO{sub 3}) can be used to separate carbon dioxide (CO{sub 2}) from coal-fired power plant flue gas. Upon thermal regeneration and condensation of water vapor, CO{sub 2} is released in a concentrated form that is suitable for reuse or sequestration. During the research project described in this report, the technical feasibility and economic viability of a thermal-swing CO{sub 2} separation process based on dry, regenerable, carbonate sorbents was confirmed. This process was designated as RTI's Dry Carbonate Process. RTI tested the Dry Carbonate Process through various research phases including thermogravimetric analysis (TGA); bench-scale fixed-bed, bench-scale fluidized-bed, bench-scale co-current downflow reactor testing; pilot-scale entrained-bed testing; and bench-scale demonstration testing with actual coal-fired flue gas. All phases of testing showed the feasibility of the process to capture greater than 90% of the CO{sub 2} present in coal-fired flue gas. Attrition-resistant sorbents were developed, and these sorbents were found to retain their CO{sub 2} removal activity through multiple cycles of adsorption and regeneration. The sodium carbonate-based sorbents developed by RTI react with CO{sub 2} and water vapor at temperatures below 80 C to form sodium bicarbonate (NaHCO3) and/or Wegscheider's salt. This reaction is reversed at temperatures greater than 120 C to release an equimolar mixture of CO{sub 2} and water vapor. After condensation of the water, a pure CO{sub 2} stream can be obtained. TGA testing showed that the Na{sub 2}CO3 sorbents react irreversibly with sulfur dioxide (SO{sub 2}) and hydrogen chloride (HCl) (at the operating conditions for this process). Trace levels of these contaminants are expected to be present in desulfurized flue gas. The sorbents did not collect detectable quantities of mercury (Hg). A process was designed for the Na{sub 2}CO{sub 3}-based sorbent that

  16. Polar mesosphere summer echoes (PMSE: Review of observations and current understanding

    Directory of Open Access Journals (Sweden)

    M. Rapp

    2004-01-01

    Full Text Available Polar mesosphere summer echoes (PMSE are very strong radar echoes primarily studied in the VHF wavelength range from altitudes close to the polar summer mesopause. Radar waves are scattered at irregularities in the radar refractive index which at mesopause altitudes is effectively determined by the electron number density. For efficient scatter, the electron number density must reveal structures at the radar half wavelength (Bragg condition for monostatic radars; ~3 m for typical VHF radars. The question how such small scale electron number density structures are created in the mesopause region has been a longstanding open scientific question for almost 30 years. This paper reviews experimental and theoretical milestones on the way to an advanced understanding of PMSE. Based on new experimental results from in situ observations with sounding rockets, ground based observations with radars and lidars, numerical simulations with microphysical models of the life cycle of mesospheric aerosol particles, and theoretical considerations regarding the diffusivity of electrons in the ice loaded complex plasma of the mesopause region, a consistent explanation for the generation of these radar echoes has been developed. The main idea is that mesospheric neutral air turbulence in combination with a significantly reduced electron diffusivity due to the presence of heavy charged ice aerosol particles (radii ~5–50 nm leads to the creation of structures at spatial scales significantly smaller than the inner scale of the neutral gas turbulent velocity field itself. Importantly, owing to their very low diffusivity, the plasma structures acquire a very long lifetime, i.e., 10 min to hours in the presence of particles with radii between 10 and 50 nm. This leads to a temporal decoupling of active neutral air turbulence and the existence of small scale plasma structures and PMSE and thus readily explains observations proving the absence of neutral air turbulence at

  17. Proprioception in Dance: A Comparative Review of Understandings and Approaches to Research

    Science.gov (United States)

    Barlow, Rachel

    2018-01-01

    Proprioception is an ongoing topic of interest in dance research. Yet 'proprioception' can have a wide range of meanings, and therefore is studied in many different ways. This research presents a review of existing studies of proprioception in dance. The review comprised 4 main stages: stage (1) background research; stage (2) proposing a working…

  18. Understanding the physical attractiveness literature: Qualitative reviews versus meta-analysis.

    Science.gov (United States)

    Feingold, Alan

    2017-01-01

    The target article is a qualitative review of selected findings in the physical attractiveness literature. This commentary explains why the meta-analytic approach, frequently used by other attractiveness reviewers, is preferable for drawing unbiased conclusions about the effects of attractiveness. The article's main contribution is affording a foundation for subsequent meta-analysis of the studies discussed in a subjective fashion.

  19. Fearing Fat: A Literature Review of Family Systems Understandings and Treatments of Anorexia and Bulimia.

    Science.gov (United States)

    Killian, Kyle D.

    1994-01-01

    Reviews literature examining family variables associated with anorexia nervosa and bulimia nervosa and family systems treatments for these eating disorders. Presents definitions of and diagnostic criteria for anorexia and bulimia, and discusses prevalence of these disorders. Reviews role played by psychopathological, sociological, and…

  20. The Calcium-Looping technology for CO_2 capture: On the important roles of energy integration and sorbent behavior

    International Nuclear Information System (INIS)

    Perejón, Antonio; Romeo, Luis M.; Lara, Yolanda; Lisbona, Pilar; Martínez, Ana; Valverde, Jose Manuel

    2016-01-01

    Highlights: • The Calcium Looping (CaL) technology is a potentially low cost and highly efficient postcombustion CO_2 capture technology. • Energy integration and sorbent behavior play a relevant role on the process. • The industrial competitiveness of the process depends critically on the minimization of energy penalties. • It may be used in precombustion capture systems and other industrial processes such as cement production. • Sorbent deactivation must be assessed under realistic conditions involving high CO_2 concentration in the calciner. - Abstract: The Calcium Looping (CaL) technology, based on the multicyclic carbonation/calcination of CaO in gas–solid fluidized bed reactors at high temperature, has emerged in the last years as a potentially low cost technology for CO_2 capture. In this manuscript a critical review is made on the important roles of energy integration and sorbent behavior in the process efficiency. Firstly, the strategies proposed to reduce the energy demand by internal integration are discussed as well as process modifications aimed at optimizing the overall efficiency by means of external integration. The most important benefit of the high temperature CaL cycles is the possibility of using high temperature streams that could reduce significantly the energy penalty associated to CO_2 capture. The application of the CaL technology in precombustion capture systems and energy integration, and the coupling of the CaL technology with other industrial processes are also described. In particular, the CaL technology has a significant potential to be a feasible CO_2 capture system for cement plants. A precise knowledge of the multicyclic CO_2 capture behavior of the sorbent at the CaL conditions to be expected in practice is of great relevance in order to predict a realistic capture efficiency and energy penalty from process simulations. The second part of this manuscript will be devoted to this issue. Particular emphasis is put on the

  1. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir Gupta; Alejandro Lopez-Ortiz

    2001-01-01

    Four grades of sodium bicarbonate and two grades of trona were characterized in terms of particle size distribution, surface area, pore size distribution, and attrition. Surface area and pore size distribution determinations were conducted after calcination of the materials. The sorbent materials were subjected to thermogravimetric testing to determine comparative rates and extent of calcination (in inert gas) and sorption (in a simulated coal combustion flue gas mixture). Selected materials were exposed to five calcination/sorption cycles and showed no decrease in either sorption capacity or sorption rate. Process simulations were conducted involving different heat recovery schemes. The process is thermodynamically feasible. The sodium-based materials appear to have suitable physical properties for use as regenerable sorbents and, based on thermogravimetric testing, are likely to have sorption and calcination rates that are rapid enough to be of interest in full-scale carbon sequestration processes.

  2. Bench-scale Development of an Advanced Solid Sorbent-based CO2 Capture Process for Coal-fired Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Thomas [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Kataria, Atish [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Soukri, Mustapha [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Farmer, Justin [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Mobley, Paul [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Tanthana, Jak [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Wang, Dongxiang [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Wang, Xiaoxing [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Song, Chunshan [Research Triangle Institute (RTI), Research Triangle Park, NC (United States)

    2015-12-31

    and potential to achieve the DOE’s Carbon Capture Program’s goal of >90% CO2 capture rate at a cost of < $40/T-CO2 captured by 2025. Through this integrated technology development approach, the project team has advanced RTI’s CO2 capture technology to TRL-4 (nearly TRL-5, with the missing variable being testing on actual, coal-fired flue gas), according to the DOE/FE definitions for Technology Readiness Levels. At a broader level, this project has advanced the whole of the solid sorbent CO2 capture field, with advancements in process engineering and design, technical risk mitigation, sorbent scale-up optimization, and an understanding of the commercial viability and applicability of solid sorbent CO2 capture technologies for the U.S. existing fleet of coal-fired power plants.

  3. Durable zinc ferrite sorbent pellets for hot coal gas desulfurization

    Science.gov (United States)

    Jha, Mahesh C.; Blandon, Antonio E.; Hepworth, Malcolm T.

    1988-01-01

    Durable, porous sulfur sorbents useful in removing hydrogen sulfide from hot coal gas are prepared by water pelletizing a mixture of fine zinc oxide and fine iron oxide with inorganic and organic binders and small amounts of activators such as sodium carbonate and molybdenite; the pellets are dried and then indurated at a high temperature, e.g., 1800.degree. C., for a time sufficient to produce crush-resistant pellets.

  4. Sorbents for effective removal of radioactive antimony during chemical decontamination

    International Nuclear Information System (INIS)

    Nishad, Padala Abdul; Bhaskarapillai, Anupkumar; Velmurugan, Sankaralingam

    2014-01-01

    Removal of radioactive antimony is a challenging problem. Often, during decontamination, they get mobilized around the system and redeposit in different areas thus offsetting the reduction in the radiation field obtained by removing other activities such as 60 Co. Thus, there is a clear need for better antimony removing materials/strategies for effective reactor decontamination. In this regard, six commercially available sorbents namely, Tulsion A33 (strong base anion (-OH) resin), Amberlite IRC-718 (chelating resin), Radex ® Sb-1000, nano TiO 2 -special grade (Inorganic type IX), Chitosan (biosorbent) and Aeroxide p25 (nano TiO 2 , Inorganic type IX) were evaluated for their antimony sorption properties. Radex ® and TiO 2 based materials were found to be more effective in removing both Sb(V) and Sb(III). Solution pH was seen to significantly influence the antimony sorption and the effect was more prominent in anion resin, when tested under column conditions. Apart from the commercial sorbents, we have synthesised a robust high performing sorbent (TA-Chitosan beads) in the form of stable beads, using nano-TiO 2 and chitosan. The beads were found to retain the antimony sorption properties of the nano-TiO 2 , while adapting a physical format suitable for large scale operations. The sorbent exhibited almost complete sorption of antimony both in low (ppb level) as well as high concentrations of antimony. The suitability of the beads for use in column mode has been established and its radiation stability was probed in detail. The beads were found to be stable to irradiations as ascertained from the TOC values and unchanged sorption properties. The sorption properties of the CHITA beads in typical decontamination formulation containing mixture of complexing agents have been investigated in detail. (author)

  5. The effect of preparation of biogenic sorbent on zinc sorption

    Directory of Open Access Journals (Sweden)

    Jana Jenčárová

    2011-12-01

    Full Text Available The aim of this study is to prepare biogenic sulphides by using bacteria for the removal of zinc cations from their solutions. Theproduction was realized in a bioreactor under anaerobic conditions at 30 °C. Sorbents were prepared by sulphate-reducing bacteria indifferent nutrient medium modifications, under two modes of bacteria cultivation. Created precipitates of iron sulphides were removedfrom the liquid phase of the cultivation medium by filtration, dried and used for the sorption experiments.

  6. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    International Nuclear Information System (INIS)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; William J. McMichael; Douglas P. Harrison; Ya Liang

    2002-01-01

    The objective of this project is to develop a simple, inexpensive process to separate CO(sub 2) as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbents being investigated in this project are primarily alkali carbonates, and particularly sodium carbonate and potassium carbonate, which are converted to bicarbonates, through reaction with carbon dioxide and water vapor. Bicarbonates are regenerated to carbonates when heated, producing a nearly pure CO(sub 2) stream after condensation of water vapor. This quarter, electrobalance tests conducted at LSU indicated that exposure of sorbent to water vapor prior to contact with carbonation gas does not significantly increase the reaction rate. Calcined fine mesh trona has a greater initial carbonation rate than calcined sodium bicarbonate, but appears to be more susceptible to loss of reactivity under severe calcination conditions. The Davison attrition indices for Grade 5 sodium bicarbonate, commercial grade sodium carbonate and extra fine granular potassium carbonate were, as tested, outside of the range suitable for entrained bed reactor testing. Fluidized bed testing at RTI indicated that in the initial stages of reaction potassium carbonate removed 35% of the carbon dioxide in simulated flue gas, and is reactive at higher temperatures than sodium carbonate. Removals declined to 6% when 54% of the capacity of the sorbent was exhausted. Carbonation data from electrobalance testing was correlated using a shrinking core reaction model. The activation energy of the reaction of sodium carbonate with carbon dioxide and water vapor was determined from nonisothermal thermogravimetry

  7. Understanding the Impact of Rewards on Employees’ Creativity and Innovation: a Literature Review Study

    OpenAIRE

    Al-Mahdawiy, Badeel

    2016-01-01

    Purpose: The purpose of this master’s thesis is to study how organizational rewards; intrinsic rewards and extrinsic monetary and non-monetary rewards, affect employees’ creativity and innovation within an organizational environment, and to propose a new categorization of organizational rewards. Methodology: A literature review of selected peer-reviewed studies from different countries and industries. Findings: The results of this study support the following notions; (1) intrinsic rewards sup...

  8. Enhanced capture of elemental mercury by bamboo-based sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Zengqiang [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Xiang, Jun, E-mail: xiangjun@mail.hust.edu.cn [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Su, Sheng, E-mail: susheng_sklcc@hotmail.com [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Zeng, Hancai; Zhou, Changsong; Sun, Lushi; Hu, Song; Qiu, Jianrong [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer The KI-modified BC has excellent capacity for elemental mercury removal. Black-Right-Pointing-Pointer The chemisorption plays a dominant role for the modified BC materials. Black-Right-Pointing-Pointer The BC-I has strong anti-poisoning ability with the presence of NO or SO{sub 2}. - Abstract: To develop cost-effective sorbent for gas-phase elemental mercury removal, the bamboo charcoal (BC) produced from renewable bamboo and KI modified BC (BC-I) were used for elemental mercury removal. The effect of NO, SO{sub 2} on gas-phase Hg{sup 0} adsorption by KI modified BC was evaluated on a fixed bed reactor using an online mercury analyzer. BET surface area analysis, temperature programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS) were used to determine the pore structure and surface chemistry of the sorbents. The results show that KI impregnation reduced the sorbents' BET surface area and total pore volume compared with that of the original BC. But the BC-I has excellent adsorption capacity for elemental mercury at a relatively higher temperature of 140 Degree-Sign C and 180 Degree-Sign C. The presence of NO or SO{sub 2} could inhibit Hg{sup 0} capture, but BC-I has strong anti-poisoning ability. The specific reaction mechanism has been further analyzed.

  9. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Alejandro Lopez-Ortiz; Douglas P. Harrison; Ya Liang

    2001-07-01

    Sodium based sorbents including sodium carbonate may be used to capture carbon dioxide from flue gas. A relatively concentrated carbon dioxide stream may be recoverable for sequestration when the sorbent is regenerated. Electrobalance tests indicated that sodium carbonate monohydrate was formed in a mixture of helium and water vapor at temperatures below 65 C. Additional compounds may also form, but this could not be confirmed. In the presence of carbon dioxide and water vapor, both the initial reaction rate of sodium carbonate with carbon dioxide and water and the sorbent capacity decreased with increasing temperature, consistent with the results from the previous quarter. Increasing the carbon dioxide concentration at constant temperature and water vapor concentration produced a measurable increase in rate, as did increasing the water vapor concentration at constant carbon dioxide concentration and temperature. Runs conducted with a flatter TGA pan resulted in a higher initial reaction rate, presumably due to improved gas-solid contact, but after a short time, there was no significant difference in the rates measured with the different pans. Analyses of kinetic data suggest that the surface of the sodium carbonate particles may be much hotter than the bulk gas due to the highly exothermic reaction with carbon dioxide and water, and that the rate of heat removal from the particle may control the reaction rate. A material and energy balance was developed for a cyclic carbonation/calcination process which captures about 26 percent of the carbon dioxide present in flue gas available at 250 C.

  10. Cleanup of Savannah River Plant solvent using solid sorbents

    International Nuclear Information System (INIS)

    Mailen, J.C.; Tallent, O.K.

    1985-04-01

    The degradation products produced in Purex solvent by exposure to nitric acid and radiation can be divided into two groups: those which are removed by scrubbing with sodium carbonate solutions and those which are not; these latter materials are called secondary degradation products. This study investigated the use of solid sorbents for removal of the secondary degradation products from first-cycle Savannah River Plant solvent that had been previously washed with sodium carbonate solution. Silica gel, activated charcoal, macroreticular resin, attapulgite clay and activated alumina were the sorbents investigated in preliminary testing. Activated alumina was found to be most effective for improving phase separation of the solvent from sodium carbonate solutions and for increasing the interfacial tension. The activated alumina was also the sorbent most useful for removing complexants which retain plutonium at low acidity, but it was less effective in removing anionic surfactants and ruthenium. We found that the capacity of the activated alumina was greatly improved by drying the solvent before treatment

  11. Advances in organic-inorganic hybrid sorbents for the extraction of organic and inorganic pollutants in different types of food and environmental samples.

    Science.gov (United States)

    Ng, Nyuk-Ting; Kamaruddin, Amirah Farhan; Wan Ibrahim, Wan Aini; Sanagi, Mohd Marsin; Abdul Keyon, Aemi S

    2018-01-01

    The efficiency of the extraction and removal of pollutants from food and the environment has been an important issue in analytical science. By incorporating inorganic species into an organic matrix, a new material known as an organic-inorganic hybrid material is formed. As it possesses high selectivity, permeability, and mechanical and chemical stabilities, organic-inorganic hybrid materials constitute an emerging research field and have become popular to serve as sorbents in various separaton science methods. Here, we review recent significant advances in analytical solid-phase extraction employing organic-inorganic composite/nanocomposite sorbents for the extraction of organic and inorganic pollutants from various types of food and environmental matrices. The physicochemical characteristics, extraction properties, and analytical performances of sorbents are discussed; including morphology and surface characteristics, types of functional groups, interaction mechanism, selectivity and sensitivity, accuracy, and regeneration abilities. Organic-inorganic hybrid sorbents combined with extraction techniques are highly promising for sample preparation of various food and environmental matrixes with analytes at trace levels. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Dual layer hollow fiber sorbents for trace H2S removal from gas streams

    KAUST Repository

    Bhandari, Dhaval A.; Bessho, Naoki; Koros, William J.

    2013-01-01

    Hollow fiber sorbents are pseudo monolithic materials with potential use in various adsorption based applications. Dual layer hollow fiber sorbents have the potential to allow thermal regeneration without direct contact of the regeneration fluid with the sorbent particles. This paper considers the application of dual layer hollow fiber sorbents for a case involving trace amounts of H2S removal from a simulated gas stream and offers a comparison with single layer hollow fiber sorbents. The effect of spin dope composition and core layer zeolite loading on the gas flux, H2S transient sorption capacity and pore structure are also studied. This work can be used as a guide to develop and optimize dual layer hollow fiber sorbent properties beyond the specific example considered here. © 2013 Elsevier Ltd.

  13. Different sorbents in calcium looping cycle for CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Cong; Zheng, Ying; Ding, Ning [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion

    2013-07-01

    Cyclic CO{sub 2} capture using commercial pure micro CaCO{sub 3} and nano CaCO{sub 3} is investigated in this paper which focuses on the different characteristics two different sorbents during high temperature reactions. The results indicate that the nano CaCO{sub 3} sorbent has higher carbonation conversions and carbonation rates than the micro CaCO{sub 3} sorbent in the cyclic reactions. Furthermore, nano sorbent can retain its fast carbonation rates at the beginning dozens of seconds during each cycle. In contrast, the carbonation rates of micro sorbent diminish with the increase of cycle number. But, unfortunately, CaO derived from nano CaCO3 sorbent sinter much easily. Its grains, which are composed of numerous spherical nanocrystallites, experience dramatic morphological changes during high temperature reactions.

  14. Dual layer hollow fiber sorbents for trace H2S removal from gas streams

    KAUST Repository

    Bhandari, Dhaval A.

    2013-05-01

    Hollow fiber sorbents are pseudo monolithic materials with potential use in various adsorption based applications. Dual layer hollow fiber sorbents have the potential to allow thermal regeneration without direct contact of the regeneration fluid with the sorbent particles. This paper considers the application of dual layer hollow fiber sorbents for a case involving trace amounts of H2S removal from a simulated gas stream and offers a comparison with single layer hollow fiber sorbents. The effect of spin dope composition and core layer zeolite loading on the gas flux, H2S transient sorption capacity and pore structure are also studied. This work can be used as a guide to develop and optimize dual layer hollow fiber sorbent properties beyond the specific example considered here. © 2013 Elsevier Ltd.

  15. Advanced Utility Mercury-Sorbent Field-Testing Program

    Energy Technology Data Exchange (ETDEWEB)

    Ronald Landreth

    2007-12-31

    This report summarizes the work conducted from September 1, 2003 through December 31, 2007 on the project entitled Advanced Utility Mercury-Sorbent Field-Testing Program. The project covers the testing at the Detroit Edison St. Clair Plant and the Duke Power Cliffside and Buck Stations. The St. Clair Plant used a blend of subbituminous and bituminous coal and controlled the particulate emissions by means of a cold-side ESP. The Duke Power Stations used bituminous coals and controlled their particulate emissions by means of hot-side ESPs. The testing at the Detroit Edison St. Clair Plant demonstrated that mercury sorbents could be used to achieve high mercury removal rates with low injection rates at facilities that burn subbituminous coal. A mercury removal rate of 94% was achieved at an injection rate of 3 lb/MMacf over the thirty day long-term test. Prior to this test, it was believed that the mercury in flue gas of this type would be the most difficult to capture. This is not the case. The testing at the two Duke Power Stations proved that carbon- based mercury sorbents can be used to control the mercury emissions from boilers with hot-side ESPs. It was known that plain PACs did not have any mercury capacity at elevated temperatures but that brominated B-PAC did. The mercury removal rate varies with the operation but it appears that mercury removal rates equal to or greater than 50% are achievable in facilities equipped with hot-side ESPs. As part of the program, both sorbent injection equipment and sorbent production equipment was acquired and operated. This equipment performed very well during this program. In addition, mercury instruments were acquired for this program. These instruments worked well in the flue gas at the St. Clair Plant but not as well in the flue gas at the Duke Power Stations. It is believed that the difference in the amount of oxidized mercury, more at Duke Power, was the difference in instrument performance. Much of the equipment was

  16. Relating Bioavailability Parameters to the Sorbent Characteristics of PAH Polluted Soils

    DEFF Research Database (Denmark)

    Bartolome, N.; Hilber, I.; Schulin, R.

    2015-01-01

    Regulation of Hydrophobic Organic Contaminants (HOC) such as polycyclic aromatic hydrocarbons (PAHs) in soil is still based on total concentrations. However, many studies have demonstrated that not all of a pollutant’s content in soil is equally available to organisms (Reichenberg & Mayer 2006...... to several sorbent characteristics including organic and black carbon content. The results will provide a better understanding of bioavailability of PAHs in soils. Moreover, the outcomes will be discussed regarding to the potential application of chemical proxies in soil pollution risk assessment......). Over the last decade, intensive effort has been made to incorporate bioavailability into risk assessment (Cachada et al. 2014). Here, we compare total concentrations of PAH with two bioavailability parameters in 30 different soil samples from the archive of the standardized National and Zurich Cantonal...

  17. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; William J. McMichael; Douglas P. Harrison; Ya Liang

    2002-01-01

    The objective of this project is to develop a simple, inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, or ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. This quarter, five cycle thermogravimetric tests were conducted at the Louisiana State University (LSU) with sodium bicarbonate Grade 3 (SBC{number_sign}3) which showed that carbonation activity declined slightly over 5 cycles following severe calcination conditions of 200 C in pure CO{sub 2}. Three different sets of calcination conditions were tested. Initial carbonation activity (as measured by extent of reaction in the first 25 minutes) was greatest subsequent to calcination at 120 C in He, slightly less subsequent to calcination in 80% CO{sub 2}/20% H{sub 2}O, and lowest subsequent to calcination in pure CO{sub 2} at 200 C. Differences in the extent of reaction after 150 minutes of carbonation, subsequent to calcination under the same conditions followed the same trend but were less significant. The differences between fractional carbonation under the three calcination conditions declined with increasing cycles. A preliminary fixed bed reactor test was also conducted at LSU. Following calcination, the sorbent removed approximately 19% of the CO{sub 2} in the simulated flue gas. CO{sub 2} evolved during subsequent calcination was consistent with an extent of carbonation of approximately 49%. Following successful testing of SBC{number_sign}3 sorbent at RTI reported in the last quarter, a two cycle fluidized bed reactor test was conducted with trona as the sorbent precursor, which was calcined to sodium carbonate. In the first

  18. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    International Nuclear Information System (INIS)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; William J. McMichael; Douglas P. Harrison; Ya Liang

    2002-01-01

    The objective of this project is to develop a simple, inexpensive process to separate CO(sub 2) as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, or ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO(sub 2) stream after condensation of water vapor. This quarter, five cycle thermogravimetric tests were conducted at the Louisiana State University (LSU) with sodium bicarbonate Grade 3 (SBC(number s ign)3) which showed that carbonation activity declined slightly over 5 cycles following severe calcination conditions of 200 C in pure CO(sub 2). Three different sets of calcination conditions were tested. Initial carbonation activity (as measured by extent of reaction in the first 25 minutes) was greatest subsequent to calcination at 120 C in He, slightly less subsequent to calcination in 80% CO(sub 2)/20% H(sub 2)O, and lowest subsequent to calcination in pure CO(sub 2) at 200 C. Differences in the extent of reaction after 150 minutes of carbonation, subsequent to calcination under the same conditions followed the same trend but were less significant. The differences between fractional carbonation under the three calcination conditions declined with increasing cycles. A preliminary fixed bed reactor test was also conducted at LSU. Following calcination, the sorbent removed approximately 19% of the CO(sub 2) in the simulated flue gas. CO(sub 2) evolved during subsequent calcination was consistent with an extent of carbonation of approximately 49%. Following successful testing of SBC(number s ign)3 sorbent at RTI reported in the last quarter, a two cycle fluidized bed reactor test was conducted with trona as the sorbent precursor, which was calcined to sodium carbonate. In the first carbonation cycle, CO

  19. Use of biomass sorbents for oil removal from gas station runoff.

    Science.gov (United States)

    Khan, Eakalak; Virojnagud, Wanpen; Ratpukdi, Thunyalux

    2004-11-01

    The use of biomass sorbents, which are less expensive and more biodegradable than synthetic sorbents, for oil removal from gas station runoff was investigated. A bench-scale flume experiment was conducted to evaluate the oil removal and retention capabilities of the biomass sorbents which included kapok fiber, cattail fiber, Salvinia sp., wood chip, rice husk, coconut husk, and bagasse. Polyester fiber, a commercial synthetic sorbent, was also experimented for comparison purpose. Oil sorption and desorption tests were performed at a water flow rate of 20 lmin-1. In the oil sorption tests, a 50 mgl(-1) of used engine oil-water mixture was synthesized to simulate the gas station runoff. The mass of oil sorbed for all sorbents, except coconut husk and bagasse, was greater than 70%. Cattail fiber and polyester fiber were the sorbents that provided the least average effluent oil concentrations. Oil selectivity (hydrophobic properties) and physical characteristics of the sorbents are the two main factors that influence the oil sorption capability. The used sorbents from the sorption tests were employed in the desorption tests. Results indicated that oil leached out of all the sorbents tested. Polyester fiber released the highest amount of oil, approximately 4% (mass basis) of the oil sorbed. copyright 2004 Elsevier Ltd.

  20. Research on using Mineral Sorbents for A Sorption Process in the Environment Contaminated with Petroleum Substances

    Directory of Open Access Journals (Sweden)

    Pijarowski Piotr Marek

    2014-06-01

    Full Text Available A research on diatomite sorbents was carried out to investigate their ability to remove hazardous substances from oil spillages. We used two types of sorbents available on the market with differences in material density and particles size of composition. As sorbents we used Ekoterm oil and unleaded petrol 95 coming from refinery PKN Orlen S.A. Two types of sorbents with similar chemical composition but different granulometric composition were used. They are marked as D1 and C1 samples. The fastest absorbent was C1, but D1 sample was the most absorptive.

  1. IMMOBILIZATION OF MICROALGAE ON THE SURFACE OF NEW CROSS-LINKED POLYETHYLENIMINE-BASED SORBENTS.

    Science.gov (United States)

    Vasilieva, Svetlana; Shibzukhova, Karina; Morozov, Alexey; Solovchenko, Alexei; Bessonov, Ivan; Kopitsyna, Maria; Lukyanov, Alexander; Chekanov, Konstantin; Lobakova, Elena

    2018-04-11

    We report on the use of the polyethylenimine-based (PEI) sorbents for immobilization and harvesting of microalgae (MA) cells. Specific materials assessed were porous solid polymers from highly-branched PEI synthesized by cross-linking with epichlorohydrin (ECH) or diethylene glycol diglycidyl ether (DGDE). We estimated the effect of PEI/cross-linker ratio on the MA attachment and biocompatibility of the sorbents with the MA cells. A decrease in the cross-linker percentage resulted in the enhancement of the immobilization efficiency but impaired the cell viability as was manifested by inhibition of the photosynthetic activity of the MA cells. The rate of Chlorella vulgaris cell attachment to the sorbents with ECH was faster as compared to that of the PEI-DGDE-based polymers. The cells immobilized on the PEI-ECH sorbents showed a more profound decline in their viability (assessed via photosynthetic activity). The sorbents with 60% of DGDE were characterized by high immobilization efficiency. These sorbents supported a prolonged cultivation of the immobilized MA without impairing their viability and metabolic activity. We conclude that the sorbents with a lower percentage of DGDE (<30%) and sorbents with ECH are suitable for harvesting of the MA cells intended for immediate downstream processing, potentially without the cell desorption. To the best of our knowledge, this is the first report on successful application of PEI-based sorbents in microalgal biotechnology. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Understanding Adoptive Families: An Integrative Review of Empirical Research and Future Directions for Counseling Psychology

    Science.gov (United States)

    O'Brien, Karen M.; Zamostny, Kathy P.

    2003-01-01

    Contrary to societal stereotypes about adoption, this integrative review of published empirical research on adoptive families noted several positive and few negative out-comes with regard to satisfaction with the adoption, familial functioning, and parent-child communication. The critical analysis of 38 studies on adoptive families revealed a…

  3. Understanding the Changing Role of Academic Librarians from a Psychological Perspective: A Literature Review

    Science.gov (United States)

    Shupe, Ellen I.; Pung, Stephanie K.

    2011-01-01

    Although issues related to the role of librarians have long been discussed in the literature on academic librarianship, there has been little attempt to incorporate the extensive psychological theory and research on role-related issues. In the current article we review the empirical literature on the role of librarians, with a particular focus on…

  4. Information Types in Nonmimetic Documents: A Review of Biddle's Wipe-Clean Slate (Understanding Documents).

    Science.gov (United States)

    Mosenthal, Peter B.; Kirsch, Irwin S.

    1991-01-01

    Describes how the 16 permanent lists used by a first grade reading teacher (and mother of 6) to manage the household represents the whole range of documents covered in the 3 major types of documents: matrix documents, graphic documents, and locative documents. Suggests class activities to clarify students' understanding of the information in…

  5. Comparative DNA isolation behaviours of silica and polymer based sorbents in batch fashion: monodisperse silica microspheres with bimodal pore size distribution as a new sorbent for DNA isolation.

    Science.gov (United States)

    Günal, Gülçin; Kip, Çiğdem; Eda Öğüt, S; İlhan, Hasan; Kibar, Güneş; Tuncel, Ali

    2018-02-01

    Monodisperse silica microspheres with bimodal pore-size distribution were proposed as a high performance sorbent for DNA isolation in batch fashion under equilibrium conditions. The proposed sorbent including both macroporous and mesoporous compartments was synthesized 5.1 μm in-size, by a "staged shape templated hydrolysis and condensation method". Hydrophilic polymer based sorbents were also obtained in the form of monodisperse-macroporous microspheres ca 5.5 μm in size, with different functionalities, by a developed "multi-stage microsuspension copolymerization" technique. The batch DNA isolation performance of proposed material was comparatively investigated using polymer based sorbents with similar morphologies. Among all sorbents tried, the best DNA isolation performance was achieved with the monodisperse silica microspheres with bimodal pore size distribution. The collocation of interconnected mesoporous and macroporous compartments within the monodisperse silica microspheres provided a high surface area and reduced the intraparticular mass transfer resistance and made easier both the adsorption and desorption of DNA. Among the polymer based sorbents, higher DNA isolation yields were achieved with the monodisperse-macroporous polymer microspheres carrying trimethoxysilyl and quaternary ammonium functionalities. However, batch DNA isolation performances of polymer based sorbents were significantly lower with respect to the silica microspheres.

  6. Applied behavior analysis: understanding and changing behavior in the community-a representative review.

    Science.gov (United States)

    Luyben, Paul D

    2009-01-01

    Applied behavior analysis, a psychological discipline, has been characterized as the science of behavior change (Chance, 2006). Research in applied behavior analysis has been published for approximately 40 years since the initial publication of the Journal of Applied Behavior Analysis in 1968. The field now encompasses a wide range of human behavior. Although much of the published research centers on problem behaviors that occur in schools and among people with disabilities, a substantial body of knowledge has emerged in community settings. This article provides a review of the behavioral community research published in the Journal of Applied Behavior Analysis as representative of this work, including research in the areas of home and family, health, safety, community involvement and the environment, recreation and sports, crime and delinquency, and organizations. In the interest of space, research in schools and with people with disabilities has been excluded from this review.

  7. An integrative review: understanding driving retirement decisions for individuals living with a dementia.

    Science.gov (United States)

    Andrew, Catherine; Traynor, Victoria; Iverson, Don

    2015-12-01

    To synthesise primary research exploring decision making practices used to determine the time to retire from driving for individuals living with a dementia. Driving requires complex cognitive and physical skills potentially compromised due to the progressive nature of dementia. Whilst on-road assessments are considered reliable indicators of driving capacity by clinicians, drivers with dementia disagree. Integrative literature review informed by Whittemore & Knafl (2005). Electronic database search of Medline, CINAHL, Web of Science, Google Scholar 1997-2012; and incremental hand search. Primary studies published in peer reviewed journals were appraised against quality assessment criteria using CASP methodological assessment tools. A total of 43 studies were retained for synthesis. Key findings were abstracted and a themes matrix was generated to identify patterns of meaning. Six themes emerged: (i) dementia may compromise the complex task of driving; (ii) defining onset and severity of dementia is problematic; (iii) symptom progression impacts on driving skills; (iv) assessment of fitness to drive remains subjective; (v) some drivers are reluctant to accept negative assessment outcomes; and (vi) the search for effective strategies to enhance acceptance of driver retirement continues. This integrative literature review identified a large body of knowledge exploring the issues of driving cessation for drivers with dementia. However a challenge remains for practitioners, drivers and their family carers regarding how best to address this highly emotive issue. Findings could inform a structured approach to address this sensitive topic in a timely manner. © 2015 The Authors. Journal of Advanced Nursing published by John Wiley & Sons Ltd.

  8. Massage therapy: understanding the mechanisms of action on blood pressure. A scoping review.

    Science.gov (United States)

    Nelson, Nicole L

    2015-10-01

    Massage therapy (MT) has shown potential in reducing blood pressure (BP); however, the psychophysiological pathways and structures involved in this outcome are unclear. The aims of this scoping review were twofold. (1) To summarize the current knowledge of the mechanisms of action of MT on BP. (2) To highlight the research gaps and challenges that researchers must overcome to further elucidate how MT attenuates BP. A scoping review was conducted to examine the evidence regarding the mechanisms of action of MT on BP. This review included the thematic analysis of 27 publications that considered the influence of MT on BP. Based on this analysis, six potential BP mediating pathways were identified Current theories suggest that MT exerts sympatholytic effects through physiologic and psychological mechanisms, improves hypothalamus-pituitary-adrenocortical axis function, and increases in blood flow, which, in turn, may improve endothelial function. Future study is needed, using more scientifically rigorous methodology, to fully elucidate the mechanism of action of MT. Copyright © 2015 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

  9. How can GPS technology help us better understand exposure to the food environment? A systematic review

    Directory of Open Access Journals (Sweden)

    Andreea Cetateanu

    2016-12-01

    Full Text Available Purpose: Global Positioning Systems (GPS are increasingly being used to objectively assess movement patterns of people related to health behaviours. However research detailing their application to the food environment is scarce. This systematic review examines the application of GPS in studies of exposure to food environments and their potential influences on health. Methods: Based on an initial scoping exercise, published articles to be included in the systematic review were identified from four electronic databases and reference lists and were appraised and analysed, the final cut-off date for inclusion being January 2015. Included studies used GPS to identify location of individuals in relation to food outlets and link that to health or diet outcomes. They were appraised against a set of quality criteria. Results: Six studies met the inclusion criteria, which were appraised to be of moderate quality. Newer studies had a higher quality score. Associations between observed mobility patterns in the food environment and diet related outcomes were equivocal. Findings agreed that traditional food exposure measures overestimate the importance of the home food environment. Conclusions: The use of GPS to measure exposure to the food environment is still in its infancy yet holds much potential. There are considerable variations and challenges in developing and standardising the methods used to assess exposure. Keywords: Global positioning systems, Geographic information system, Food environments, Food exposure, Systematic review

  10. How do people of South Asian origin understand and experience depression? A protocol for a systematic review of qualitative literature.

    Science.gov (United States)

    Mooney, Roisin; Trivedi, Daksha; Sharma, Shivani

    2016-08-30

    Individuals from Black and Asian Minority Ethnic (BAME) groups are less likely to receive a diagnosis and to engage with treatment for depression. This review aims to draw on international literature to summarise what is known about how people specifically of South Asian origin, migrants and non-migrants, understand and experience depressive symptoms. The resulting evidence base will further inform practices aimed at encouraging help-seeking behaviour and treatment uptake. A systematic review and thematic synthesis of qualitative literature conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Using predefined inclusion and exclusion criteria, electronic searches will be conducted across 16 databases. Study quality will be assessed using the Critical Appraisal Skills Programme (CASP). Data will be extracted independently by 2 reviewers. Ethical approval is not required. A comprehensive evidence base of how people from South Asian backgrounds conceptualise and experience depression will better inform the design and delivery of mental health initiatives and advance directions for future research. Findings will be published in a peer-reviewed journal, and disseminated through existing networks for professionals, researchers, patients and the public. CRD42015026120. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  11. Systematic review to understand and improve care after stillbirth: a review of parents' and healthcare professionals' experiences.

    Science.gov (United States)

    Ellis, Alison; Chebsey, Caroline; Storey, Claire; Bradley, Stephanie; Jackson, Sue; Flenady, Vicki; Heazell, Alexander; Siassakos, Dimitrios

    2016-01-25

    2.7 million babies were stillborn in 2015 worldwide; behind these statistics lie the experiences of bereaved parents. The first Lancet series on stillbirth in 2011 described stillbirth as one of the "most shamefully neglected" areas of public health, recommended improving interaction between families and frontline caregivers and made a plea for increased investment in relevant research. A systematic review of qualitative, quantitative and mixed-method studies researching parents and healthcare professionals experiences of care after stillbirth in high-income westernised countries (Europe, North America, Australia and South Africa) was conducted. The review was designed to inform research, training and improve care for parents who experience stillbirth. Four thousand four hundred eighty eight abstracts were identified; 52 studies were eligible for inclusion. Synthesis and quantitative aggregation (meta-summary) was used to extract findings and calculate frequency effect sizes (FES%) for each theme (shown in italics), a measure of the prevalence of that finding in the included studies. Researchers' areas of interest may influence reporting of findings in the literature and result in higher FES sizes, such as; support memory making (53%) and fathers have different needs (18%). Other parental findings were more unexpected; Parents want increased public awareness (20%) and for stillbirth care to be prioritised (5%). Parental findings highlighted lessons for staff; prepare parents for vaginal birth (23%), discuss concerns (13%), give options & time (20%), privacy not abandonment (30%), tailored post-mortem discussions (20%) and post-natal information (30%). Parental and staff findings were often related; behaviours and actions of staff have a memorable impact on parents (53%) whilst staff described emotional, knowledge and system-based barriers to providing effective care (100%). Parents reported distress being caused by midwives hiding behind 'doing' and ritualising

  12. Development of composite calcium hydroxide sorbent in mechanical operations and evaluation of its basic sorption properties

    Directory of Open Access Journals (Sweden)

    Gara Paweł

    2017-01-01

    Full Text Available This article presents the results of research carried out on the possibility of obtaining composite calcium hydroxide sorbent in the process of two-step granulation, containing additional compounds of Al, Mg and Fe, and their textural and sorption studies. For this purpose, attempts were undertaken to compact commercial calcium hydroxide powder with six additives in the laboratory roll press. The resulting compacts were crushed and sieved in order to achieve the assumed sieve fraction. Based on the obtained results, basic parameters of the process of formation of composite sorbent have been determined. Both, the selected composite sorbents fractions and additives were subsequently subjected to textural studies (determination of the specific surface area and porosity and sorption capacity performance. In addition, for the better interpretation of the results, thermogravimetric studies were carried out both for the additives and composite sorbents, as well as the grain size distribution of the additives. The results of the physicochemical tests of the obtained composite sorbents were compared with analogic results from the study on fine-grained hydroxide sorbent without additives and carbonate sorbent. The presented results showed that in a two-step granulation process it is possible to obtain the granular Ca(OH2 sorbent, as well as composite sorbents possessing better SO2 sorption capacity in comparison to the powder Ca(OH2 and/or to the calcium carbonate sorbent. This can be attributed to the combination of capability of the sorbent to appropriate thermal decomposition and the formation of a group of pores in the range of 0.07-0.3 microns.

  13. Improving understanding in the research informed consent process: a systematic review of 54 interventions tested in randomized control trials.

    Science.gov (United States)

    Nishimura, Adam; Carey, Jantey; Erwin, Patricia J; Tilburt, Jon C; Murad, M Hassan; McCormick, Jennifer B

    2013-07-23

    Obtaining informed consent is a cornerstone of biomedical research, yet participants comprehension of presented information is often low. The most effective interventions to improve understanding rates have not been identified. To systematically analyze the random controlled trials testing interventions to research informed consent process. The primary outcome of interest was quantitative rates of participant understanding; secondary outcomes were rates of information retention, satisfaction, and accrual. Interventional categories included multimedia, enhanced consent documents, extended discussions, test/feedback quizzes, and miscellaneous methods. The search spanned from database inception through September 2010. It was run on Ovid MEDLINE, Ovid EMBASE, Ovid CINAHL, Ovid PsycInfo and Cochrane CENTRAL, ISI Web of Science and Scopus. Five reviewers working independently and in duplicate screened full abstract text to determine eligibility. We included only RCTs. 39 out of 1523 articles fulfilled review criteria (2.6%), with a total of 54 interventions. A data extraction form was created in Distiller, an online reference management system, through an iterative process. One author collected data on study design, population, demographics, intervention, and analytical technique. Meta-analysis was possible on 22 interventions: multimedia, enhanced form, and extended discussion categories; all 54 interventions were assessed by review. Meta-analysis of multimedia approaches was associated with a non-significant increase in understanding scores (SMD 0.30, 95% CI, -0.23 to 0.84); enhanced consent form, with significant increase (SMD 1.73, 95% CI, 0.99 to 2.47); and extended discussion, with significant increase (SMD 0.53, 95% CI, 0.21 to 0.84). By review, 31% of multimedia interventions showed significant improvement in understanding; 41% for enhanced consent form; 50% for extended discussion; 33% for test/feedback; and 29% for miscellaneous.Multiple sources of variation

  14. Understanding bureaucracy in health science ethics: toward a better institutional review board.

    Science.gov (United States)

    Bozeman, Barry; Slade, Catherine; Hirsch, Paul

    2009-09-01

    Research involving human participants continues to grow dramatically, fueled by advances in medical technology, globalization of research, and financial and professional incentives. This creates increasing opportunities for ethical errors with devastating effects. The typical professional and policy response to calamities involving human participants in research is to layer on more ethical guidelines or strictures. We used a recent case-the Johns Hopkins University/Kennedy Kreiger Institute Lead Paint Study-to examine lessons learned since the Tuskegee Syphilis Study about the role of institutionalized science ethics in the protection of human participants in research. We address the role of the institutional review board as the focal point for policy attention.

  15. Review of the current understanding of the potential for containment failure from in-vessel steam explosions

    International Nuclear Information System (INIS)

    1985-06-01

    A group of experts was convened to review the current understanding of the potential for containment failure from in-vessel steam explosions during core meltdown accidents in LWRs. The Steam Explosion Review Group (SERG) was requested to provide assessments of: (1) the conditional probability of containment failure due to a steam explosion, (2) a Sandia National Laboratory (SNL) report entitled ''An Uncertainty Study of PWR Steam Explosions,'' NUREG/CR-3369, (3) a SNL proposed steam explosion research program. This report summarizes the results of the deliberations of the review group. It also presents the detailed response of each individual member to each of the issues. The consensus of the SERG is that the occurrence of a steam explosion of sufficient energetics which could lead to alpha-mode containment failure has a low probability. The SERG members disagreed with the methodology used in NUREG/CR-3369 for the purpose of establishing the uncertainty in the probability of containment failure by a steam explosion. A consensus was reached among SERG members on the need for a continuing steam explosion research program which would improve our understanding of certain aspects of steam explosion phenomenology

  16. Resilience as a concept for understanding family caregiving of adults with Chronic Obstructive Pulmonary Disease (COPD): an integrative review.

    Science.gov (United States)

    Rosa, Francesca; Bagnasco, Annamaria; Aleo, Giuseppe; Kendall, Sally; Sasso, Loredana

    2017-04-01

    This paper was a report of the synthesis of evidence on examining the origins and definitions of the concept of resilience, investigating its application in chronic illness management and exploring its utility as a means of understanding family caregiving of adults with Chronic Obstructive Pulmonary Disease. Resilience is a concept that is becoming relevant to understanding how individuals and families live with illness, especially long-term conditions. Caregivers of adults with Chronic Obstructive Pulmonary Disease must be able to respond to exacerbations of the condition and may themselves experience cognitive imbalances. Yet, resilience as a way of understanding family caregiving of adults with COPD is little explored. Literature review - integrative review. CINAHL, PubMed, Google Scholar and EBSCO were searched between 1989-2015. The principles of rapid evidence assessment were followed. We identified 376 relevant papers: 20 papers reported the presence of the concept of resilience in family caregivers of chronic diseases patients but only 12 papers reported the presence of the concept of resilience in caregivers of Chronic Obstructive Pulmonary Disease patients and have been included in the synthesis. The term resilience in Chronic Obstructive Pulmonary Disease caregiving is most often understood using a deficit model of health.

  17. FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID REMOVAL

    Energy Technology Data Exchange (ETDEWEB)

    Gary M. Blythe

    2004-01-01

    The objective of this project has been to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. The project was co-funded by the U.S. DOE National Energy Technology Laboratory under Cooperative Agreement DE-FC26-99FT40718, along with EPRI, the American Electric Power Company (AEP), FirstEnergy Corporation, the Tennessee Valley Authority, and Carmeuse North America. Sulfuric acid controls are becoming of increased interest for coal-fired power generating units for a number of reasons. In particular, sulfuric acid can cause plant operation problems such as air heater plugging and fouling, back-end corrosion, and plume opacity. These issues will likely be exacerbated with the retrofit of selective catalytic reduction (SCR) for NOX control, as SCR catalysts are known to further oxidize a portion of the flue gas SO{sub 2} to SO{sub 3}. The project tested the effectiveness of furnace injection of four different magnesium-based or dolomitic alkaline sorbents on full-scale utility boilers. These reagents were tested during one- to two-week tests conducted on two FirstEnergy Bruce Mansfield Plant (BMP) units. One of the sorbents tested was a magnesium hydroxide slurry byproduct from a modified Thiosorbic{reg_sign} Lime wet flue gas desulfurization process. The other three sorbents are available commercially and include dolomite, pressure-hydrated dolomitic lime, and commercially available magnesium hydroxide. The dolomite reagent was injected as a dry powder through out-of-service burners. The other three reagents were injected as slurries through air-atomizing nozzles inserted through the front wall of the upper furnace. After completing the four one- to two-week tests, the most promising sorbents were selected for longer-term (approximately 25-day) full-scale tests on two different units. The longer-term tests were conducted to confirm sorbent effectiveness over extended operation on two

  18. Using qualitative methods to understand factors contributing to patient satisfaction among dermatology patients: a systematic review.

    Science.gov (United States)

    Gibbons, Caitlin; Singh, Sanminder; Gibbons, Brittany; Clark, Caitlin; Torres, Josefina; Cheng, Michelle Y; Wang, Elizabeth A; Armstrong, April W

    2018-05-01

    In this systematic review, we aimed to synthesize data that identify factors contributing to patient satisfaction in dermatology care using qualitative methods. We performed a comprehensive search of the literature using the PubMed database for articles published between January 1, 2000 and February 9, 2015. The initial search yielded 186 articles, of which 13 were included after applying inclusion and exclusion criteria. The systematic review of 13 articles included a total of 330 patients. Using in-field observations and semistructured interviews, studies found that qualitative methods and analysis increased the provider's sensitivity to patient needs and enhanced patient care. Analyses using qualitative methods found increased patient satisfaction in their healthcare provider is associated with (1) confidence in the provider's diagnosis, (2) perception of patient-centered, individualized recommendations and (3) quality of patient education and provider explanation during a visit. Patient satisfaction is measured using either quantitative or qualitative methods. Quantitative methods result in standardized data that often does not capture the nuances of patient experience. In contrast, qualitative methodology is integral to gathering patient perspectives on patient care and satisfaction and should be included in future research models.

  19. Understanding the role of waste prevention in local waste management: A literature review.

    Science.gov (United States)

    Zacho, Kristina O; Mosgaard, Mette A

    2016-10-01

    Local waste management has so far been characterised by end-of-pipe solutions, landfilling, incineration, and recycling. End-of-pipe solutions build on a different mind-set than life cycle-based approaches, and for this reason, local waste managers are reluctant to consider strategies for waste prevention. To accelerate the transition of waste and resource management towards a more integrated management, waste prevention needs to play a larger role in the local waste management. In this review article, we collect knowledge from the scientific community on waste prevention of relevance to local waste management. We analyse the trends in the waste prevention literature by organising the literature into four categories. The results indicate an increasing interest in waste prevention, but not much literature specifically concerns the integration of prevention into the local waste management. However, evidence from the literature can inform local waste management on the prevention potential; the environmental and social effects of prevention; how individuals in households can be motivated to reduce waste; and how the effects of prevention measures can be monitored. Nevertheless, knowledge is still lacking on local waste prevention, especially regarding the methods for monitoring and how local waste management systems can be designed to encourage waste reduction in the households. We end the article with recommendations for future research. The literature review can be useful for both practitioners in the waste sector and for academics seeking an overview of previous research on waste prevention. © The Author(s) 2016.

  20. Understanding mineral trioxide aggregate/Portland-cement: a review of literature and background factors.

    Science.gov (United States)

    Steffen, R; van Waes, H

    2009-06-01

    This was to carry out a review of the literature concerning mineral trioxide aggregate (MTA) and Portland cement with regards to clinical, biological and mechanical findings and a possible substitution of MTA through Portland cement for endodontic use. Electronic literature search of scientific papers from January 1993 to January 2009 was carried out on the MEDLINE and Scopus databases using specific key words. In total, 57 papers were identified that dealt with MTA and Portland cement in a relevant way. The review of 50 papers conforming to the applied criteria showed that MTA and Portland cements have the same clinical, biological and mechanical properties. In animal experiments and technical characterisations both materials seemed to have very similar properties. The only difference is bismuth oxide in MTA added for better radio opacity. It seems likely that MTA materials are based on industrial Portland cements mixed with bismuth oxide. More studies, especially some long-term studies comparing MTA and Portland cement, are necessary. The existing literature gives a solid base for clinical studies with Portland cement in order to replace MTA as an endodontic material. Portland cement could be a substitute for most endodontic materials used in primary teeth.

  1. How can GPS technology help us better understand exposure to the food environment? A systematic review.

    Science.gov (United States)

    Cetateanu, Andreea; Jones, Andy

    2016-12-01

    Global Positioning Systems (GPS) are increasingly being used to objectively assess movement patterns of people related to health behaviours. However research detailing their application to the food environment is scarce. This systematic review examines the application of GPS in studies of exposure to food environments and their potential influences on health. Based on an initial scoping exercise, published articles to be included in the systematic review were identified from four electronic databases and reference lists and were appraised and analysed, the final cut-off date for inclusion being January 2015. Included studies used GPS to identify location of individuals in relation to food outlets and link that to health or diet outcomes. They were appraised against a set of quality criteria. Six studies met the inclusion criteria, which were appraised to be of moderate quality. Newer studies had a higher quality score. Associations between observed mobility patterns in the food environment and diet related outcomes were equivocal. Findings agreed that traditional food exposure measures overestimate the importance of the home food environment. The use of GPS to measure exposure to the food environment is still in its infancy yet holds much potential. There are considerable variations and challenges in developing and standardising the methods used to assess exposure.

  2. The spectroscopic study of building composites containing natural sorbents.

    Science.gov (United States)

    Król, M; Mozgawa, W

    2011-08-15

    This work presents the results of FT-IR spectroscopic studies of heavy metal cations (Ag(+), Pb(2+), Zn(2+), Cd(2+) and Cr(3+)) immobilization from aqueous solutions on natural sorbents. The sorption has been conducted on sodium forms of zeolite (clinoptilolite) and clay minerals (mixtures containing mainly montmorillonite and kaolinite) which have been separated from natural Polish deposit. In the next part of the work both sorbents were used to obtain new building composites. It was proven those heavy metal cations' sorption causes changes in IR spectra of the zeolite and clay minerals. These alterations are dependent on the way the cations were sorbed. In the case of zeolite, variations of the bands corresponding to the characteristic ring vibrations have been observed. These rings occur in pseudomolecular complexes 4-4-1 (built of alumino- and silicooxygen tetrahedra) which constitute the secondary building units (SBU) and form spatial framework of the zeolite. The most significant changes have been determined in the region of pseudolattice vibrations (650-700 cm(-1)). In the instance of clay minerals, changes in the spectra occur at two ranges: 1200-800 cm(-1)--the range of the bands assigned to asymmetric Si-O(Si,Al) and bending Al-OH vibrations and 3800-3000 cm(-1)--the range of the bands originating from OH(-) groups stretching vibrations. Next results indicate possibilities of applying the used natural sorbents for the obtainment of new building materials having favourable composition and valuable properties. The zeolite was used for obtaining autoclaved materials with an addition of CaO, and the clay minerals for ceramic sintered materials with an addition of quartz and clinoptilolite were produced. FT-IR studies were also conducted on the obtained materials. Copyright © 2010 Elsevier B.V. All rights reserved.

  3. Microwave synthesis of nanostructured oxide sorbents doped with lanthanides

    Energy Technology Data Exchange (ETDEWEB)

    Mitrofanov, Andrey A., E-mail: mitrofanov-a@icloud.com; Silyavka, Elena S.; Shilovskikh, Vladimir V.; Kolonitckii, Petr D.; Sukhodolov, Nikolai G.; Selyutin, Artem A., E-mail: selutin@inbox.ru [Saint Petersburg State University, 7/9, Universitetskaya nab., St. Petersburg, 199034 (Russian Federation)

    2016-06-17

    A number of nanostructured mesoporous oxide systems based on aluminum oxide, doped with lanthanide ions have been obtained in this study. Structure and morphology of oxides obtained have been examined by X-ray diffraction analysis, thermogravimetric analysis, scanning electron microscopy. The surface area of the samples was determined by the BET method. The dependence of the adsorption of insulin on synthesized oxides from the concentration was investigated. The containing of insulin in solutions after adsorption was determined by the Bradford method. The isotherms of adsorption of insulin on resulting oxide sorbents were plotted, the dependence capacity of the sorption of insulin from the lanthanide dopant was determined.

  4. Durable zinc oxide-containing sorbents for coal gas desulfurization

    Science.gov (United States)

    Siriwardane, Ranjani V.

    1996-01-01

    Durable zinc-oxide containing sorbent pellets for removing hydrogen sulfide from a gas stream at an elevated temperature are made up to contain titania as a diluent, high-surface-area silica gel, and a binder. These materials are mixed, moistened, and formed into pellets, which are then dried and calcined. The resulting pellets undergo repeated cycles of sulfidation and regeneration without loss of reactivity and without mechanical degradation. Regeneration of the pellets is carried out by contacting the bed with an oxidizing gas mixture.

  5. Social media and rating sites as tools to understanding quality of care: a scoping review.

    Science.gov (United States)

    Verhoef, Lise M; Van de Belt, Tom H; Engelen, Lucien J L P G; Schoonhoven, Lisette; Kool, Rudolf B

    2014-02-20

    Insight into the quality of health care is important for any stakeholder including patients, professionals, and governments. In light of a patient-centered approach, it is essential to assess the quality of health care from a patient's perspective, which is commonly done with surveys or focus groups. Unfortunately, these "traditional" methods have significant limitations that include social desirability bias, a time lag between experience and measurement, and difficulty reaching large groups of people. Information on social media could be of value to overcoming these limitations, since these new media are easy to use and are used by the majority of the population. Furthermore, an increasing number of people share health care experiences online or rate the quality of their health care provider on physician rating sites. The question is whether this information is relevant to determining or predicting the quality of health care. The goal of our research was to systematically analyze the relation between information shared on social media and quality of care. We performed a scoping review with the following goals: (1) to map the literature on the association between social media and quality of care, (2) to identify different mechanisms of this relationship, and (3) to determine a more detailed agenda for this relatively new research area. A recognized scoping review methodology was used. We developed a search strategy based on four themes: social media, patient experience, quality, and health care. Four online scientific databases were searched, articles were screened, and data extracted. Results related to the research question were described and categorized according to type of social media. Furthermore, national and international stakeholders were consulted throughout the study, to discuss and interpret results. Twenty-nine articles were included, of which 21 were concerned with health care rating sites. Several studies indicate a relationship between information

  6. Current understanding of bleeding with ibrutinib use: a systematic review and meta-analysis.

    Science.gov (United States)

    Caron, François; Leong, Darryl P; Hillis, Christopher; Fraser, Graeme; Siegal, Deborah

    2017-05-09

    Ibrutinib therapy was associated with an increased risk of bleeding in previous trials. In this systematic review and meta-analysis of published trials including patients treated with ibrutinib, the relative risk (95% confidence interval [CI]) of overall bleeding was significantly higher in ibrutinib recipients (2.72 [1.62-6.58]), but major bleeding did not show a significant difference (1.66 [0.96-2.85]). The incidences (95% CI) of major bleeding and any bleeding were 3.0 (2.3-3.7) and 20.8 (19.1-22.1) per 100 patient-years, respectively. This analysis is limited by reporting bias from variable ascertainment of bleeding and lack of allocation concealment in some studies and differing exposures between groups, leading to potential overestimation of event rates in the ibrutinib group.

  7. Understanding mechanisms and the role of differentiation in pathogenesis of Toxoplasma gondii: a review

    Directory of Open Access Journals (Sweden)

    William J Sullivan Jr

    2009-03-01

    Full Text Available Parasite differentiation from proliferating tachyzoites into latent bradyzoites is central to pathogenesis and transmission of the intracellular protozoan pathogen Toxoplasma gondii. The presence of bradyzoite-containing cysts in human hosts and their subsequent rupture can cause life-threatening recrudescence of acute infection in the immunocompromised and cyst formation in other animals contributes to zoonotic transmission and widespread dissemination of the parasite. In this review, we discuss the evidence showing how the clinically relevant process of bradyzoite differentiation is regulated at both transcriptional and post-transcriptional levels. Specific regulatory factors implicated in modulating bradyzoite differentiation include promoter-based cis-elements, epigenetic modifications and protein translation control through eukaryotic initiation factor -2 (eIF2. In addition to a summary of the current state of knowledge in these areas we discuss the pharmacological ramifications and pose some questions for future research.

  8. Understanding Central Mechanisms of Acupuncture Analgesia Using Dynamic Quantitative Sensory Testing: A Review

    Directory of Open Access Journals (Sweden)

    Jiang-Ti Kong

    2013-01-01

    Full Text Available We discuss the emerging translational tools for the study of acupuncture analgesia with a focus on psychophysical methods. The gap between animal mechanistic studies and human clinical trials of acupuncture analgesia calls for effective translational tools that bridge neurophysiological data with meaningful clinical outcomes. Temporal summation (TS and conditioned pain modulation (CPM are two promising tools yet to be widely utilized. These psychophysical measures capture the state of the ascending facilitation and the descending inhibition of nociceptive transmission, respectively. We review the basic concepts and current methodologies underlying these measures in clinical pain research, and illustrate their application to research on acupuncture analgesia. Finally, we highlight the strengths and limitations of these research methods and make recommendations on future directions. The appropriate addition of TS and CPM to our current research armamentarium will facilitate our efforts to elucidate the central analgesic mechanisms of acupuncture in clinical populations.

  9. Understanding HIV-Related Stigma Among Women in the Southern United States: A Literature Review.

    Science.gov (United States)

    Darlington, Caroline K; Hutson, Sadie P

    2017-01-01

    Societal stigmatization of HIV/AIDS due to assumptions about transmission and associated behaviors plays a substantial role in the psychosocial well-being of people living with this chronic illness, particularly for women in traditionally conservative geographic regions. Known for social conservatism, the Southern United States (US) holds the highest incidence rate of HIV infection in the US. A systematic search of four databases was used to identify 27 relevant scientific articles pertaining to HIV-related stigma among women living with HIV/AIDS in the Southern US. These studies revealed a rudimentary understanding of stigma sources, effects, and stigma-reduction interventions in this population. Due to the cultural specificity of stigma, further differentiation of stigma in discrete sectors of the South as well as a dialogue about the moral implications of stigma is necessary to lay the groundwork for patient-centered interventions to mitigate the destructive effects of stigma experienced by women in this region.

  10. Understanding the bereavement care roles of nurses within acute care: a systematic review.

    Science.gov (United States)

    Raymond, Anita; Lee, Susan F; Bloomer, Melissa J

    2017-07-01

    To investigate nurses' roles and responsibilities in providing bereavement care during the care of dying patients within acute care hospitals. Bereavement within acute care hospitals is often sudden, unexpected and managed by nurses who may have limited access to experts. Nurses' roles and experience in the provision of bereavement care can have a significant influence on the subsequent bereavement process for families. Identifying the roles and responsibilities, nurses have in bereavement care will enhance bereavement supports within acute care environments. Mixed-methods systematic review. The review was conducted using the databases Cumulative Index Nursing and Allied Health Literature Plus, Embase, Ovid MEDLINE, PsychINFO, CareSearch and Google Scholar. Included studies published between 2006-2015, identified nurse participants, and the studies were conducted in acute care hospitals. Seven studies met the inclusion criteria, and the research results were extracted and subjected to thematic synthesis. Nurses' role in bereavement care included patient-centred care, family-centred care, advocacy and professional development. Concerns about bereavement roles included competing clinical workload demands, limitations of physical environments in acute care hospitals and the need for further education in bereavement care. Further research is needed to enable more detailed clarification of the roles nurse undertake in bereavement care in acute care hospitals. There is also a need to evaluate the effectiveness of these nursing roles and how these provisions impact on the bereavement process of patients and families. The care provided by acute care nurses to patients and families during end-of-life care is crucial to bereavement. The bereavement roles nurses undertake are not well understood with limited evidence of how these roles are measured. Further education in bereavement care is needed for acute care nurses. © 2016 John Wiley & Sons Ltd.

  11. Understanding the impact of simulated patients on health care learners' communication skills: a systematic review.

    Science.gov (United States)

    Kaplonyi, Jessica; Bowles, Kelly-Ann; Nestel, Debra; Kiegaldie, Debra; Maloney, Stephen; Haines, Terry; Williams, Cylie

    2017-12-01

    Effective communication skills are at the core of good health care. Simulated patients (SPs) are increasingly engaged as an interactive means of teaching, applying and practising communication skills with immediate feedback. There is a large body of research into the use of manikin-based simulation but a gap exists in the body of research on the effectiveness of SP-based education to teach communication skills that impact patient outcomes. The aim of this systematic review was to critically analyse the existing research, investigating whether SP-based communication skills training improves learner-patient communication, how communication skill improvement is measured, and who measures these improvements. The databases Medline, ProQuest (Health & Medical Complete, Nursing and Allied Health Source) and CINAHL (EBSCOhost) Education Resources Information Centre (ERIC) were searched for articles that investigated the effects of SP-based education on the communication skills of medical, nursing and allied health learners. There were 60 studies included in the review. Only two studies reported direct patient outcomes, one reporting some negative impact, and no studies included an economic analysis. Many studies reported statistically significant third-party ratings of improved communication effectiveness following SP-based education; however, studies were unable to be pooled for meta-analysis because of the outcome collection methods. There were a small number of studies comparing SP with no training at all and there were no differences between communication skills, contradicting the results from studies reporting benefits. Of the 60 studies included for analysis, 54 (90%) met the minimum quality score of 7/11, with four articles (7%) scoring 11/11. SP-based education is widely accepted as a valuable and effective means of teaching communication skills but there is limited evidence of how this translates to patient outcomes and no indication of economic benefit for this

  12. Uncovering Astronomy Students’ Understandings of the Age of the Universe: A Literature Review

    Science.gov (United States)

    Grundstrom, Erika; Slater, T.; Stassun, K.

    2008-05-01

    Most education reform documents describing what students should understand about astronomy include concepts surrounding the immense size scale and ancient age of our Universe. If an appreciation for "deep time” is needed to develop mastery of astronomical concepts, then astronomy educators need to become aware of how students, and the general public, think about concepts of immense timescales. As a first step toward addressing this issue, we conducted a survey of the educational research literature on students’ conceptions of long timescales. Most recent research efforts have focused on two strategies. One is to show figures illustrating geologic strata to students who are asked to determine the sequence of events based on the concepts of original horizontality and superposition with younger sediments overlying older sediments. The other research design is to employ a card-sorting technique where people are asked to arrange events in order in relative sequence and sometimes asked to space them on a timeline. The key finding is that students can often place historical events in the correct relative order but are unable to place them with correct relative spacing or accurate absolute dates. Other findings are that current research does not reveal gender or racial biases in student thinking and it does not show that students always distinguish between the Big Bang and the formation of the Sun or Earth. It is clear that researchers in earth science education have not focused on cosmological time frames, only geologic time frames, thus leaving an important deficit in the literature. Prior to turning our attention to curriculum materials development focused on improving student understanding of long timescales in astronomy, we plan to expand these studies to include cosmological events.

  13. Toward a better understanding of the future of the solo medical practitioner in health care industry: a conceptual review.

    Science.gov (United States)

    Erdem, S A; Lacombe, B

    1998-01-01

    Even a brief conceptual review of the current developments in the health care industry indicates that the future of independent medical practitioners is rather challenging. It may be necessary for these parties to pursue proactive and aggressive marketing strategies to be able to compete with the managed care organizations. Accordingly, this paper outlines some of the current trends in health care marketing as they relate to the ongoing changes to which solo medical practitioners need to respond. It is hoped that the review of the issues raised in this paper can provide an initial basis for a better understanding of some of the challenges to come up with more comprehensive and effective strategy decisions.

  14. SORBENT/UREA SLURRY INJECTION FOR SIMULTANEOUS SO2/NOX REMOVAL

    Science.gov (United States)

    The combination of sorbent injection and selective noncatalytic reduction (SNCR) technologies has been investigated for simulataneous SO2/NOx removal. A slurry composed of a urea-based solution and various Ca-based sorbents was injected at a range of tempera...

  15. Adsorption of H2O and CO2 on supported amine sorbents

    NARCIS (Netherlands)

    Veneman, Rens; Frigka, Natalia; Zhao, Wenying; Li, Zhenshan; Kersten, Sascha R.A.; Brilman, Derk Willem Frederik

    2015-01-01

    In this work the adsorption of H2O and CO2 on Lewatit VP OC 1065 was studied in view of the potential application of this sorbent in post combustion CO2 capture. Both CO2 and H2O were found to adsorb on the amine active sites present on the pore surface of the sorbent material. However, where the

  16. Synthesis of hydroxide type sorbents from industry high-iron wastes

    International Nuclear Information System (INIS)

    Stepanenko, E.K.; Smirnov, A.L.

    1986-01-01

    Article presents the results of studies on possibility of using of technological iron containing wastes for the obtaining of hydroxide type sorbents in granular form. The scheme of technology of synthesis of hydroxide type sorbents from high-iron wastes is elaborated.

  17. Evaluation of hydrous ferric oxide loaded activated carbon as a granular composite sorbent for radiostrontium

    International Nuclear Information System (INIS)

    Samanta, S.K.

    1997-01-01

    A composite sorbent was prepared in granular form by depositing hydrous ferric oxide inside the pores of activated carbon. The composite sorbent was found to show excellent sorption of radiostrontium in the presence of high sodium concentration under alkaline conditions. (author). 3 refs., 2 figs., 1 tab

  18. Coating membranes for a sorbent-based artificial liver: adsorption characteristics

    NARCIS (Netherlands)

    de Koning, H. W.; Chamuleau, R. A.; Bantjes, A.

    1982-01-01

    Techniques are described for the coating of sorbents to be used in an artificial liver support system based on mixed sorbent bed hemoperfusion. Activated charcoal has been coated with cellulose acetate (CA) by solvent evaporation. With Amberlite XAD-4, the Wurster technique was used for coating with

  19. Cross-linked poly(tetrahydrofuran) as promising sorbent for organic solvent/oil spill

    Energy Technology Data Exchange (ETDEWEB)

    Yati, Ilker; Ozan Aydin, Gulsah; Bulbul Sonmez, Hayal, E-mail: hayalsonmez@gtu.edu.tr

    2016-05-15

    Highlights: • Poly(tetrahydrofuran) based sorbents were prepared. • PTHF sorbents demonstrate reusability at least for ten times. • PTHF based sorbents show fast and quick absorption-desorption process. • 19 g of oil can be absorbed by 1 g of PTHF based sorbent. - Abstract: In this study, a series of different molecular weights of poly(tetrahydrofuran) (PTHF), which is one of the most important commercial polymers around the world, was condensed with tris[3-(trimethoxysilyl)propyl]isocyanurate (ICS) to generate a cross-linked 3-dimensional network in order to obtain organic solvent/oil sorbents having high swelling capacity. The prepared sorbents show high and fast swelling capacity in oils such as dichloromethane (DCM), tetrahydrofuran (THF), acetone, t-butyl methyl ether (MTBE), gasoline, euro diesel, and crude oil. The recovery of the absorbed oils from contaminated surfaces, especially from water, and the regeneration of the sorbents after several applications are effective. The characterization and thermal properties of the sorbents are identified by Fourier transform infrared spectroscopy (FTIR), solid-state {sup 13}C and {sup 29}Si cross-polarization magic angle spinning (CPMAS) nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC) and thermal gravimetric analyses (TGA), respectively. The new usage area of PTHF is emerged by the preparation of PTHF-based network structure with high oil absorption capacity and having excellent reusability as an oil absorbent for the removal of organic liquids from the spill site.

  20. Synthesis and test of sorbents based on calcium aluminates for SE-SR

    International Nuclear Information System (INIS)

    Barelli, L.; Bidini, G.; Di Michele, A.; Gallorini, F.; Petrillo, C.; Sacchetti, F.

    2014-01-01

    Highlights: • Synthesis strategy of CaO incorporation into calcium aluminates was approached. • Three innovative sorbents (M1, M2, M3) were synthesized and characterized. • Sorption capacity of developed sorbents was evaluated in multi-cycle processes. • M3 sorbent showed best performance, much higher than conventional CaO ones. • M3 sorbent functionality in SE-SR process was verified. - Abstract: Greenhouse gases emission of power generation plants will be continuously tightened to achieve European targets in terms of CO 2 emissions. In particular, the switching to a sustainable power generation using fossil fuels will be strongly encouraged in the future. In this context, sorption-enhanced steam reforming (SE-SR) is a promising process because it can be implemented as a CCS pre-combustion methodology. The purpose of this study is to develop and test innovative materials in order to overcome main limitations of standard CaO sorbent, usually used in the SE-SR process. The investigated innovative sorbents are based on incorporation of CaO particles into inert materials which significantly reduce the performance degradation. In particular, sorbent materials based on calcium aluminates were considered, investigating different techniques of synthesis. All synthesized materials were packed, together with the catalyst, in a fixed bed reactor and tested in sorption/regeneration cycles. Significant improvements were obtained respect to standard CaO regarding sorption capacity stability exhibited by the sorbent

  1. Development of New Potassium Carbonate Sorbent for CO2 Capture under Real Flue Gas Conditions

    Directory of Open Access Journals (Sweden)

    Javad Esmaili

    2014-07-01

    Full Text Available In this paper, the development of a new potassium carbonateon alumina support sorbent prepared by impregnating K2CO3 with an industrial grade of Al2O3 support was investigated. The CO2 capture capacity was measured using real flue gas with 8% CO2 and 12% H2O in a fixed-bed reactor at a temperature of 65 °C using breakthrough curves. The developed sorbent showed an adsorption capacity of 66.2 mgCO2/(gr sorbent. The stability of sorbent capture capacity was higher than the reference sorbent. The SO2 impurity decreased sorbent capacity about 10%. The free carbon had a small effect on sorbent capacity after 5 cycles. After 5 cycles of adsorption and regeneration, the changes in the pore volume and surface area were 0.020 cm3/gr and 5.5 m2/gr respectively. Small changes occurred in the pore size distribution and surface area of sorbent after 5 cycles.

  2. Effect of characteristic of sorbents on their sulfur capture capability at a fluidized bed condition

    Energy Technology Data Exchange (ETDEWEB)

    Leming Cheng; Bo Chen; Ni Liu; Zhongyang Luo; Kefa Cen [Zhejiang University, Hangzhou (China). Clean Energy and Environment Engineering Key Lab of Ministry of Education, Institute for Thermal Power Engineering

    2004-05-01

    This research was intent for finding relationships among physical and/or chemical properties of sorbents and their sulfur capture capability at a fluidized bed condition. Three limestones and two seashells were chosen as a SO{sub 2} sorbent. Characteristics of sorbents were evaluated based on atomic absorption spectrophotometer, scanning electron microscope and mercury-penetration porosimeter analyses. Their sulfur capture capabilities were measured on a fluidized bed test system at 800, 850, 900 and 950{sup o}C. Conversion of the sobents was computed and analyzed depending on the sorbents' morphology and microstructure analysis. Results showed pore size and specific surface might have large influence on sorbents' desulfurization ability in the range of 800 950{sup o}C. 14 refs., 6 figs., 4 tabs.

  3. Experimental research on combustion fluorine retention using calcium-based sorbents during coal combustion (II)

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Q.; Ma, X.; Liu, J.; Wu, X.; Zhou, J.; Cen, K. [Liaoning Technical University, Fuxin (China). College of Resource and Environment Engineering

    2008-12-15

    Fluoride pollution produced by coal burning can be controlled with the calcium-based sorbent combustion fluorine technique in which calcium-based sorbents are mixed with the coal or sprayed into the combustion chamber. In a fixed bed tube furnace combustion experiment using one calcium-based natural mineral, limestone and one calcium-based building material, it was shown that the calcium-based sorbent particle grain size and pore structure have a big influence on the combustion fluorine retention effect. Reducing the calcium-based sorbent particle grain size and improving the calcium sorbent structure characteristics at very high temperature to enhance the fluorine retention effect is the important approach to the fluorine retention agent development. 8 refs., 1 fig., 5 tabs.

  4. Preparation and characterisation of a sorbent suitable for technetium separation from environmental matrices

    International Nuclear Information System (INIS)

    Bartosova, A.; Rajec, P.; Reich, M.

    2003-01-01

    A sorbent based on Aliquat 336 anchored on hydrophobised silica gel support as an ion exchanger was prepared. Prepared sorbent was suitable for separation of technetium-99 from environmental matrices. The sorbent properties, sorption characteristic and distribution coefficient of 99 mTcO 4 - in various medium was studied. The chemical yield of Tc during separation process was determined using 99m Tc tracer and gamma measurement. Typical sorption recoveries of Tc for this sorbent from 0.1 M HNO 3 were more than 98 %. Typical desorption recoveries using 8 M HNO 3 were in the range 92 - 96 %. The commercial TEVA Spec resin from Eichrom Industries for comparison purpose was used as well. It was found that the prepared sorbent is suitable for separation of technetium from environmental matrices. (authors)

  5. [Contributions of cortisol suppression tests to understanding of psychiatric disorders: a narrative review of literature].

    Science.gov (United States)

    Tajima-Pozo, Kazuhiro; Montes-Montero, Ana; Güemes, Itziar; González-Vives, Sara; Díaz-Marsá, Marina; Carrasco, José Luis

    2013-01-01

    Activity of the hypothalamic-pituitary-adrenal axis had been studied for the past half century, when some researchers noted that some patients with Cushing's syndrome and severe mood disorders had high baseline cortisol levels, which resulted in an inhibited response in the 1mg dexamethasone suppression test. Altered dexamethasone suppression test results were subsequently found in many psychiatric diseases, including anorexia nervosa, obsessive-compulsive disorder, degenerative dementia, bipolar disorders, and schizophrenia. The relationship between high baseline cortisol levels and stress has also been studied. Some researches on the genesis of borderline personality disorder focused on traumatic childhood backgrounds. Other investigations aimed at elucidating the relationship between traumatic backgrounds and some psychiatric disorders noted that patients with post-traumatic stress disorder and borderline personality disorder showed an enhanced cortisol suppression with low cortisol doses (0.5 mg). Recent studies showed that use of an ultra-low dose of cortisol during the dexamethasone suppression test may be helpful for detecting disorders with hyperactivity of the hypothalamic-pituitary-adrenal axis. Recent advances in neuroimaging support the existence of hyperactivity of the hypothalamic-pituitary-adrenal axis in patients with borderline personality disorder, relating a decreased pituitary gland volume to major traumatic backgrounds and suicidal attempts. The purpose of this paper is to make a narrative review of research using dexamethasone suppression test in psychiatric disorders, in order to ascertain its value as a supplemental diagnostic test or as a prognostic marker. Copyright © 2012 SEEN. Published by Elsevier Espana. All rights reserved.

  6. A review of constructivism: understanding and using a relatively new theory.

    Science.gov (United States)

    Whitman, N

    1993-09-01

    The purpose of this review paper is to familiarize family medicine educators with a relatively new educational theory, "constructivism." This theory is derived from the philosophical proposition that reality is constructed by the individual. According to the more traditional theory of "objectivism," knowledge exists in the world external to personal experience. Constructivist theory postulates that personal experience cannot be separated from knowledge. In analyzing the literature, the author found that constructivism can be viewed at the cognitive (individual) and social (community) levels. Cognitive constructivism maintains that individuals develop their own models of reality using personal experience and research-based data. Two key elements of cognitive constructivism with implications for family medicine educators are promoting student independence and active learning. Social constructivism maintains that individuals use their membership in a community to continually refine and shape their models of reality. By communicating with each other (for physicians, in the "conversation of medicine"), we test our constructs. Two key elements of social constructivism with implications for application by family medicine educators are promoting collaboration and peer teaching.

  7. Understanding Children and Adolescents' Victimizations at Multiple Levels: An Ecological Review of the Literature.

    Science.gov (United States)

    Sabri, Bushra; Hong, Jun Sung; Campbell, Jacquelyn C; Cho, Hyunkag

    2013-05-01

    This article examines children and adolescent exposure to violence in various contexts. A systematic review of the literature was conducted to identify the definitions and types of violence reported in studies on victimization using the ecological systems framework. Sources included research studies and/or reports from scholarly journals ( n = 140), books ( n = 9), conference/workshops ( n = 5), and web sources, such as Uniform Crime Reports ( n = 23). The findings indicated that research differed in terminologies, conceptual and operational definitions, sample sizes and age group classification for children and adolescents. Further, studies lacked focus on the co-occurrence and inter-relatedness of victimization, and how these factors might affect the outcomes. Many studies employed a cross-sectional design, which limits strong conclusions about the temporal order of victimization experiences and outcomes. Future research efforts need more consistency among researchers in conceptual and operational definitions and the use of more rigorous designs. Increased holistic assessments are critical for effective prevention and intervention strategies for at-risk children and adolescents.

  8. Understanding Children and Adolescents’ Victimizations at Multiple Levels: An Ecological Review of the Literature

    Science.gov (United States)

    Sabri, Bushra; Hong, Jun Sung; Campbell, Jacquelyn C.; Cho, Hyunkag

    2013-01-01

    This article examines children and adolescent exposure to violence in various contexts. A systematic review of the literature was conducted to identify the definitions and types of violence reported in studies on victimization using the ecological systems framework. Sources included research studies and/or reports from scholarly journals (n = 140), books (n = 9), conference/workshops (n = 5), and web sources, such as Uniform Crime Reports (n = 23). The findings indicated that research differed in terminologies, conceptual and operational definitions, sample sizes and age group classification for children and adolescents. Further, studies lacked focus on the co-occurrence and inter-relatedness of victimization, and how these factors might affect the outcomes. Many studies employed a cross-sectional design, which limits strong conclusions about the temporal order of victimization experiences and outcomes. Future research efforts need more consistency among researchers in conceptual and operational definitions and the use of more rigorous designs. Increased holistic assessments are critical for effective prevention and intervention strategies for at-risk children and adolescents PMID:24065867

  9. Understanding Counterfactuality: A Review of Experimental Evidence for the Dual Meaning of Counterfactuals

    Science.gov (United States)

    Nieuwland, Mante S.

    2016-01-01

    Abstract Cognitive and linguistic theories of counterfactual language comprehension assume that counterfactuals convey a dual meaning. Subjunctive‐counterfactual conditionals (e.g., ‘If Tom had studied hard, he would have passed the test’) express a supposition while implying the factual state of affairs (Tom has not studied hard and failed). The question of how counterfactual dual meaning plays out during language processing is currently gaining interest in psycholinguistics. Whereas numerous studies using offline measures of language processing consistently support counterfactual dual meaning, evidence coming from online studies is less conclusive. Here, we review the available studies that examine online counterfactual language comprehension through behavioural measurement (self‐paced reading times, eye‐tracking) and neuroimaging (electroencephalography, functional magnetic resonance imaging). While we argue that these studies do not offer direct evidence for the online computation of counterfactual dual meaning, they provide valuable information about the way counterfactual meaning unfolds in time and influences successive information processing. Further advances in research on counterfactual comprehension require more specific predictions about how counterfactual dual meaning impacts incremental sentence processing. PMID:27512408

  10. Reply to Jaakkola (2014): "Do animals understand invisible displacement? A critical review".

    Science.gov (United States)

    Pepperberg, Irene M

    2015-05-01

    Jaakkola (2014) critiques studies that investigate nonhuman capacities to track objects undergoing invisible displacements. She states that the results of most of these studies are tainted by cuing, that conceptual understanding is lacking, and that, as a consequence, great apes are the only nonhumans to have full Stage 6 object permanence. Any critique, however, must clearly take into account all published information on the techniques being used, including more recent data that counter its negative claims. Furthermore, disagreements as to the interpretation of the underlying mechanisms, although common, need not always cast doubt on the actual findings reported. Here I present material with respect to Grey parrots (Psittacus erithacus) to counter Jaakkola's critique. First, I take issue with Jaakkola's claims of cuing, based both on data from newer studies and citations from the original material. Second, I discuss her suggestions that associative learning rather than inferential mechanisms underlie demonstrated performance, pointing out some difficulties in drawing clear lines between the 2 interpretations. In sum, I argue that Grey parrots, at least, do indeed succeed on tasks involving invisible displacement, and demonstrate full object permanence. (c) 2015 APA, all rights reserved).

  11. Understanding value in health data ecosystems: A review of current evidence and ways forward.

    Science.gov (United States)

    Sonja, Marjanovic; Ioana, Ghiga; Miaoqing, Yang; Anna, Knack

    2018-01-01

    The potential of health data to improve the efficiency and effectiveness of health research and development, healthcare delivery, and health systems more widely is substantial. There are many initiatives across the EU that are experimenting with ways to capture value and address the nexus of technical, legal, ethics-related, governance and data protection-related, and cultural challenges to delivering potential benefits for society and the economy. The field of health data research and policy is highly dynamic and there is a need for further reflection, thematic learning and evaluation to better understand how to create and connect receptive places, to inform future interventions and to identify transferable lessons. Our research emphasises that realising the benefits of health data at scale will require: a simultaneous focus on the technological and structural conditions that are required; collaboration and coordination to transform working cultures and build health and care workforce and citizen capacity to engage with data; and efforts to ensure that policy, industry, and research communities respond to public concerns, needs, and expectations in a timely and sustained manner. The global community of individuals and organisations with a stake in health data will also need to consider how progress can benefit different populations across the world in an equitable manner.

  12. Enhanced capture of elemental mercury by bamboo-based sorbents

    International Nuclear Information System (INIS)

    Tan, Zengqiang; Xiang, Jun; Su, Sheng; Zeng, Hancai; Zhou, Changsong; Sun, Lushi; Hu, Song; Qiu, Jianrong

    2012-01-01

    Highlights: ► The KI-modified BC has excellent capacity for elemental mercury removal. ► The chemisorption plays a dominant role for the modified BC materials. ► The BC-I has strong anti-poisoning ability with the presence of NO or SO 2 . - Abstract: To develop cost-effective sorbent for gas-phase elemental mercury removal, the bamboo charcoal (BC) produced from renewable bamboo and KI modified BC (BC-I) were used for elemental mercury removal. The effect of NO, SO 2 on gas-phase Hg 0 adsorption by KI modified BC was evaluated on a fixed bed reactor using an online mercury analyzer. BET surface area analysis, temperature programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS) were used to determine the pore structure and surface chemistry of the sorbents. The results show that KI impregnation reduced the sorbents’ BET surface area and total pore volume compared with that of the original BC. But the BC-I has excellent adsorption capacity for elemental mercury at a relatively higher temperature of 140 °C and 180 °C. The presence of NO or SO 2 could inhibit Hg 0 capture, but BC-I has strong anti-poisoning ability. The specific reaction mechanism has been further analyzed.

  13. Arsenic removal using natural biomaterial-based sorbents.

    Science.gov (United States)

    Ansone, Linda; Klavins, Maris; Viksna, Arturs

    2013-10-01

    Arsenic contamination of water is a major problem worldwide. A possible solution can be approached through developing new sorbents based on cost-effective and environmentally friendly natural biomaterials. We have developed new sorbents based on biomaterial impregnation with iron oxyhydroxide. In this study, raw peat material, iron-modified peat, iron-modified biomass (shingles, straw, sands, cane and moss) as well as iron humate were used for the removal of arsenate from contaminated water. The highest sorption capacity was observed in iron-modified peat, and kinetic studies indicated that the amount of arsenic sorbed on this material exceeds 90 % in 5 h. Arsenate sorption on iron-modified peat is characterised by the pseudo-second-order mechanism. The results of arsenic sorption in the presence of competing substances indicated that sulphate, nitrate, chloride and tartrate anions have practically no influence on As(V) sorption onto Fe-modified peat, whereas the presence of phosphate ions and humic acid significantly lowers the arsenic removal efficiency.

  14. Tin in canned food: a review and understanding of occurrence and effect.

    Science.gov (United States)

    Blunden, Steve; Wallace, Tony

    2003-12-01

    Tinplate is light gauge, steel sheet or strip, coated on both sides with commercially pure tin and has been used for well over a hundred years as a robust form of food packaging. Altogether, about 25,000 million food cans are produced and filled in Europe per annum, about 20% of these having plain internal (unlacquered) tin-coated steel bodies. Worldwide, the total for food packaging is approximately 80,000 million cans. Tinplate is also extensively used for the production of beverage cans. Europe produces and fills over 15,000 million tinplate beverage cans per annum all of which are internally lacquered. The use of tinplate for food and beverage packaging, will result in some tin dissolving into the food content, particularly when plain uncoated internal surfaces are used. The Provisional Tolerable Weekly Intake for tin is 14 mg/kg body weight and recommended maximum permissible levels of tin in food are typically 250 mg/kg (200 mg/kg UK) for solid foods and 150 mg/kg for beverages. However, the question arises as to whether evidence exists that such elevated levels of tin in food in any way constitute a risk to human health. This review considers the factors affecting the dissolution of tin, the reported measurements/surveys of actual levels of tin in canned foods and the studies and reports of acute (short term) toxicity relating to the ingestion of elevated levels of tin in food products. Chronic studies are mentioned, but are not covered in detail, since the review is mainly concerned with possible effects from the ingestion of single high doses. From published data, there appears to be a small amount of evidence suggesting that consumption of food or beverages containing tin at concentrations at or below 200 ppm has caused adverse gastrointestinal effects in an unknown but possibly small proportion of those exposed. However, the evidence supporting this assertion is derived from reports of adverse effects which offer data that are limited, incomplete or of

  15. Understanding of the impact of chemicals on amphibians: a meta-analytic review.

    Science.gov (United States)

    Egea-Serrano, Andrés; Relyea, Rick A; Tejedo, Miguel; Torralva, Mar

    2012-07-01

    Many studies have assessed the impact of different pollutants on amphibians across a variety of experimental venues (laboratory, mesocosm, and enclosure conditions). Past reviews, using vote-counting methods, have described pollution as one of the major threats faced by amphibians. However, vote-counting methods lack strong statistical power, do not permit one to determine the magnitudes of effects, and do not compare responses among predefined groups. To address these challenges, we conducted a meta-analysis of experimental studies that measured the effects of different chemical pollutants (nitrogenous and phosphorous compounds, pesticides, road deicers, heavy metals, and other wastewater contaminants) at environmentally relevant concentrations on amphibian survival, mass, time to hatching, time to metamorphosis, and frequency of abnormalities. The overall effect size of pollutant exposure was a medium decrease in amphibian survival and mass and a large increase in abnormality frequency. This translates to a 14.3% decrease in survival, a 7.5% decrease in mass, and a 535% increase in abnormality frequency across all studies. In contrast, we found no overall effect of pollutants on time to hatching and time to metamorphosis. We also found that effect sizes differed among experimental venues and among types of pollutants, but we only detected weak differences among amphibian families. These results suggest that variation in sensitivity to contaminants is generally independent of phylogeny. Some publication bias (i.e., selective reporting) was detected, but only for mass and the interaction effect size among stressors. We conclude that the overall impact of pollution on amphibians is moderately to largely negative. This implies that pollutants at environmentally relevant concentrations pose an important threat to amphibians and may play a role in their present global decline.

  16. Understanding the impact of school tobacco policies on adolescent smoking behaviour: A realist review.

    Science.gov (United States)

    Schreuders, Michael; Nuyts, Paulien A W; van den Putte, Bas; Kunst, Anton E

    2017-06-01

    Secondary schools increasingly implement school tobacco policies (STPs) to decrease adolescents' smoking. Recent studies suggested that STPs' impact depends on their implementation. We examined adolescents' cognitive and behavioural responses to STPs that impact adolescents' smoking and how these responses depend on elements of STPs' implementation. To examine STPs and adolescent smoking, we performed a realist review, which is an explanatory approach that synthesizes existing evidence into a program theory that links elements of STPs' implementation to outcomes by specifying its underlying generative mechanisms. The search was performed in MEDLINE/PubMed, PsycINFO, and Embase between January 1991 and 2016. Thirty-seven English language articles were identified for inclusion, reporting quantitative and/or qualitative primary evidence on STPs at secondary schools, adolescent smoking behaviour, and mechanisms. From these articles, evidence was extracted about mechanisms that decrease smoking and associated countervailing-mechanisms that reduce, nullify, or revert this positive impact. The program theory showed that STPs may trigger four mechanisms and seven associated countervailing-mechanisms. Adolescents' smoking decreases if STPs make them feel they can get sanctioned, feel less pressure to conform to smokers, internalise anti-smoking beliefs, and find it easier to stick to the decision not to smoke. This positive impact may reduce, nullify, or revert if the implementation of STPs cause adolescents to find alternative places to smoke, develop new social meanings of smoking, want to belong in smoker groups, internalise beliefs that smoking is not bad or that it asserts personal autonomy, or alienate from schools and schools' messages. The program theory, moreover, provided insights on how elements of STPs' implementation trigger mechanisms and avoid the countervailing-mechanisms. STPs' impact can be influenced by adequate implementation and embedding them in

  17. Incorporating ecogeomorphic feedbacks to better understand resiliency in streams: A review and directions forward

    Science.gov (United States)

    Atkinson, Carla L.; Allen, Daniel C.; Davis, Lisa; Nickerson, Zachary L.

    2018-03-01

    Decades of interdisciplinary research show river form and function depends on interactions between the living and nonliving world, but a dominant paradigm underlying ecogeomorphic work consists of a top-down, unidirectional approach with abiotic forces driving biotic systems. Stream form and location within the stream network does dictate the habitat and resources available for organisms and overall community structure. Yet this traditional hierarchal framework on its own is inadequate in communicating information regarding the influence of biological systems on fluvial geomorphology that lead to changes in channel morphology, sediment cycling, and system-scale functions (e.g., sediment yield, biogeochemical nutrient cycling). Substantial evidence that organisms influence fluvial geomorphology exists, specifically the ability of aquatic vegetation and lotic animals to modify flow velocities and sediment deposition and transport - thus challenging the traditional hierarchal framework. Researchers recognize the need for ecogeomorphic frameworks that conceptualize feedbacks between organisms, sediment transport, and geomorphic structure. Furthermore, vital ecosystem processes, such as biogeochemical nutrient cycling represent the conversations that are occurring between geomorphological and biological systems. Here we review and synthesize selected case studies highlighting the role organisms play in moderating geomorphic processes and likely interact with these processes to have an impact on an essential ecosystem process, biogeochemical nutrient recycling. We explore whether biophysical interactions can provide information essential to improving predictions of system-scale river functions, specifically sediment transport and biogeochemical cycling, and discuss tools used to study these interactions. We suggest that current conceptual frameworks should acknowledge that hydrologic, geomorphologic, and ecologic processes operate on different temporal scales, generating

  18. Adaptation and Mitigation in Agriculture: A Review of Synergies and Tradeoffs and How EO Could Improve Understanding and Outcomes

    Science.gov (United States)

    Barbieri, L.; Wollenberg, E.

    2017-12-01

    We present a review of the published literature on agricultural adaptation and mitigation, and report on the current evidence as to whether changes in agricultural practices meant to achieve mitigation or adaptation goals can be dual purpose: simultaneously reducing greenhouse gas (GHG) emissions and helping to facilitate adaptation. We characterize the spatio-temporal and system trends in how adaptation and mitigation outcomes are being achieved, and report on the current technical and knowledge gaps that exist and where Earth observations (EO) could improve our understanding. Agriculture contributes 12% GHG emissions globally, roughly one third from the developing world. Nearly 70% of the technical mitigation potential in agriculture sector occurs in these countries, however, while the mitigation potential is high, agricultural productivity also relies heavily on climate factors. With climate change, agricultural systems already, and will increasingly, need to adapt to extreme events and variability in temperatures and precipitation. This underscores the importance of implementing agricultural practices that can both reduce GHG emissions and help facilitate adaptation. Until recently, these objectives have been treated separately, but policy makers are increasingly calling for a joint approach to improve synergies, and avoid tradeoffs. There remain many complications in considering a joint approach: lack of clear conceptual frameworks, knowledge gaps in scientific understanding and evidence associated with adaptation and mitigation outcomes, and the abilities and motivations of stakeholders to consider both objectives. We review 56 peer-reviewed publications and present results from an in-depth analysis to answer two major concerns: to what extent is evidence provided for claims of synergistic outcomes, and what uncertainty surrounds this evidence. Our results show that only 21% of studies empirically measured both mitigation and adaptation outcomes, and claims

  19. Revisiting the understanding of "transactional sex" in sub-Saharan Africa: A review and synthesis of the literature.

    Science.gov (United States)

    Stoebenau, Kirsten; Heise, Lori; Wamoyi, Joyce; Bobrova, Natalia

    2016-11-01

    In sub-Saharan Africa, young women ages 15-24 have more than twice the risk of acquiring HIV as their male counterparts. A growing body of epidemiological evidence suggests that the practice of "transactional sex" may contribute to this disparity. Over the last 15 years, the social sciences have contributed significantly to understanding the meaning of and motivations for this practice. The findings from these studies are rich, but varied, rendering lessons difficult to navigate for intervention and further research. We therefore contribute a historically-grounded, comprehensive literature review on the nature and motivations for women's participation in transactional sex in sub-Saharan Africa. Drawing from over 300 studies (through 2014), we distill three prominent paradigms observed in the literature that we review toward presenting a unified conceptualization of the practice. "Sex for basic needs," the first paradigm, positions women as victims in transactional sexual relationships, with implications for interventions that protect girls from exploitation. In contrast, the "sex for improved social status" paradigm positions women as sexual agents who engage in transactional sex toward attaining a middle-class status and lifestyle. Finally, a third paradigm, "sex and material expressions of love," draws attention to the connections between love and money, and the central role of men as providers in relationships. We find important commonalities in the structural factors that shape the three paradigms of transactional sex including gender inequality and processes of economic change. We suggest that there are three continua stretching across these paradigms: deprivation, agency, and instrumentality. This review proposes a definition of transactional sex and discusses implications for research and interventions aiming to reduce young women's risk of HIV through such relationships. We consider the consequences of drawing from too narrow an understanding of the

  20. A review and framework for understanding the potential impact of poor solid waste management on health in developing countries.

    Science.gov (United States)

    Ziraba, Abdhalah K; Haregu, Tilahun Nigatu; Mberu, Blessing

    2016-01-01

    The increase in solid waste generated per capita in Africa has not been accompanied by a commensurate growth in the capacity and funding to manage it. It is reported that less than 30% of urban waste in developing countries is collected and disposed appropriately. The implications of poorly managed waste on health are numerous and depend on the nature of the waste, individuals exposed, duration of exposure and availability of interventions for those exposed. To present a framework for understanding the linkages between poor solid waste management, exposure and associated adverse health outcomes. The framework will aid understanding of the relationships, interlinkages and identification of the potential points for intervention. Development of the framework was informed by a review of literature on solid waste management policies, practices and its impact on health in developing countries. A configurative synthesis of literature was applied to develop the framework. Several iterations of the framework were reviewed by experts in the field. Each linkage and outcomes are described in detail as outputs of this study. The resulting framework identifies groups of people at a heightened risk of exposure and the potential health consequences. Using the iceberg metaphor, the framework illustrates the pathways and potential burden of ill-health related to solid waste that is hidden but rapidly unfolding with our inaction. The existing evidence on the linkage between poor solid waste management and adverse health outcomes calls to action by all stakeholders in understanding, prioritizing, and addressing the issue of solid waste in our midst to ensure that our environment and health are preserved. A resulting framework developed in this study presents a clearer picture of the linkages between poor solid waste management and could guide research, policy and action.

  1. Methods and sorbents for utilizing a hot-side electrostatic precipitator for removal of mercury from combustion gases

    Science.gov (United States)

    Nelson, Sidney [Hudson, OH

    2011-02-15

    Methods are provided for reducing emission of mercury from a gas stream by treating the gas with carbonaceous mercury sorbent particles to reduce the mercury content of the gas; collecting the carbonaceous mercury sorbent particles on collection plates of a hot-side ESP; periodically rapping the collection plates to release a substantial portion of the collected carbonaceous mercury sorbent particles into hoppers; and periodically emptying the hoppers, wherein such rapping and emptying are done at rates such that less than 70% of mercury adsorbed onto the mercury sorbent desorbs from the collected mercury sorbent into the gas stream.

  2. Performance Evaluation of Engineered Structured Sorbents for Atmosphere Revitalization Systems On Board Crewed Space Vehicles and Habitats

    Science.gov (United States)

    Howard, David F.; Perry, Jay L.; Knox, James C.; Junaedi, Christian; Roychoudhury, Subir

    2011-01-01

    Engineered structured (ES) sorbents are being developed to meet the technical challenges of future crewed space exploration missions. ES sorbents offer the inherent performance and safety attributes of zeolite and other physical adsorbents but with greater structural integrity and process control to improve durability and efficiency over packed beds. ES sorbent techniques that are explored include thermally linked and pressure-swing adsorption beds for water-save dehumidification and sorbent-coated metal meshes for residual drying, trace contaminant control, and carbon dioxide control. Results from sub-scale performance evaluations of a thermally linked pressure-swing adsorbent bed and an integrated sub-scale ES sorbent system are discussed.

  3. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Douglas P. Harrison; Ya Liang

    2001-10-01

    The objective of this project is to develop a simple, inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. Testing conducted previously confirmed that the reaction rate and achievable CO{sub 2} capacity of sodium carbonate decreased with increasing temperature, and that the global rate of reaction of sodium carbonate to sodium bicarbonate increased with an increase in both CO{sub 2} and H{sub 2}O concentrations. Energy balance calculations indicated that the rate of heat removal from the particle surface may determine the reaction rate for a particular particle system. This quarter, thermogravimetric analyses (TGA) were conducted which indicated that calcination of sodium bicarbonate at temperatures as high as 200 C did not cause a significant decrease in activity in subsequent carbonation testing. When sodium bicarbonate was subjected to a five cycle calcination/carbonation test, activity declined slightly over the first two cycles but was constant thereafter. TGA tests were also conducted with two other potential sorbents. Potassium carbonate was found to be less active than sodium carbonate, at conditions of interest in preliminary TGA tests. Sodium carbonate monohydrate showed negligible activity. Testing was also conducted in a 2-inch internal diameter quartz fluidized-bed reactor system. A five cycle test demonstrated that initial removals of 10 to 15 percent of the carbon dioxide in a simulated flue gas could be achieved. The carbonation reaction proceeded at temperatures as low as 41 C. Future work by TGA and in fixed

  4. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    International Nuclear Information System (INIS)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Douglas P. Harrison; Ya Liang

    2001-01-01

    The objective of this project is to develop a simple, inexpensive process to separate CO(sub 2) as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO(sub 2) stream after condensation of water vapor. Testing conducted previously confirmed that the reaction rate and achievable CO(sub 2) capacity of sodium carbonate decreased with increasing temperature, and that the global rate of reaction of sodium carbonate to sodium bicarbonate increased with an increase in both CO(sub 2) and H(sub 2)O concentrations. Energy balance calculations indicated that the rate of heat removal from the particle surface may determine the reaction rate for a particular particle system. This quarter, thermogravimetric analyses (TGA) were conducted which indicated that calcination of sodium bicarbonate at temperatures as high as 200 C did not cause a significant decrease in activity in subsequent carbonation testing. When sodium bicarbonate was subjected to a five cycle calcination/carbonation test, activity declined slightly over the first two cycles but was constant thereafter. TGA tests were also conducted with two other potential sorbents. Potassium carbonate was found to be less active than sodium carbonate, at conditions of interest in preliminary TGA tests. Sodium carbonate monohydrate showed negligible activity. Testing was also conducted in a 2-inch internal diameter quartz fluidized-bed reactor system. A five cycle test demonstrated that initial removals of 10 to 15 percent of the carbon dioxide in a simulated flue gas could be achieved. The carbonation reaction proceeded at temperatures as low as 41 C. Future work by TGA and in fixed-bed, fluidized-bed, and transport

  5. FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID CONTROL; SEMIANNUAL

    International Nuclear Information System (INIS)

    Gary M. Blythe

    2002-01-01

    This document summarizes progress on Cooperative Agreement DE-FC26-99FT40718, Furnace Injection of Alkaline Sorbents for Sulfuric Acid Control, during the time period October 1, 2001 through March 31, 2002. The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. The coincident removal of hydrochloric acid and hydrofluoric acid is also being determined, as is the removal of arsenic, a known poison for NO(sub X) selective catalytic reduction (SCR) catalysts. EPRI, the Tennessee Valley Authority (TVA), FirstEnergy Corporation, American Electric Power (AEP) and the Dravo Lime Company are project co-funders. URS Corporation is the prime contractor. This is the fifth reporting period for the subject Cooperative Agreement. During the previous (fourth) period, two long-term sorbent injection tests were conducted, one on Unit 3 at FirstEnergy's Bruce Mansfield Plant (BMP) and one on Unit 1 at AEP's Gavin Plant. Those tests determined the effectiveness of injecting alkaline slurries into the upper furnace of the boiler as a means of controlling sulfuric acid emissions from these units. The alkaline slurries tested included commercially available magnesium hydroxide slurry (Gavin Plant) and a byproduct magnesium hydroxide slurry (at both Gavin and BMP). The tests showed that injecting either the commercial or the byproduct magnesium hydroxide slurry could achieve up to 70-75% overall sulfuric acid removal. At BMP, the overall removal was limited by the need to maintain acceptable electrostatic precipitator (ESP) particulate control performance. At Gavin Plant, the overall sulfuric acid removal was limited because the furnace injected sorbent was less effective at removing SO(sub 3) formed across the SCR system installed on the unit for NO(sub X) control than at removing SO(sub 3) formed in the furnace. The SO(sub 3) removal results were presented in the

  6. Thermochemical Characterizations of Novel Vermiculite-LiCl Composite Sorbents for Low-Temperature Heat Storage

    Directory of Open Access Journals (Sweden)

    Yannan Zhang

    2016-10-01

    Full Text Available To store low-temperature heat below 100 °C, novel composite sorbents were developed by impregnating LiCl into expanded vermiculite (EVM in this study. Five kinds of composite sorbents were prepared using different salt concentrations, and the optimal sorbent for application was selected by comparing both the sorption characteristics and energy storage density. Textural properties of composite sorbents were obtained by extreme-resolution field emission scanning electron microscopy (ER-SEM and an automatic mercury porosimeter. After excluding two composite sorbents which would possibly exhibit solution leakage in practical thermal energy storage (TES system, thermochemical characterizations were implemented through simulative sorption experiments at 30 °C and 60% RH. Analyses of thermogravimetric analysis/differential scanning calorimetry (TGA/DSC curves indicate that water uptake of EVM/LiCl composite sorbents is divided into three parts: physical adsorption of EVM, chemical adsorption of LiCl crystal, and liquid–gas absorption of LiCl solution. Energy storage potential was evaluated by theoretical calculation based on TGA/DSC curves. Overall, EVMLiCl20 was selected as the optimal composite sorbent with water uptake of 1.41 g/g, mass energy storage density of 1.21 kWh/kg, and volume energy storage density of 171.61 kWh/m3.

  7. Carbon-Containing Waste of Coal Enterprises in Magnetic Sorbents Technology

    Science.gov (United States)

    Kvashevaya, Ekaterina; Ushakova, Elena; Ushakov, Andrey

    2017-11-01

    The article shows the issues state of coal-mining enterprises carbonaceous wastes utilization, including by obtaining oil-sorbent. The characteristics of the feedstock are presented; experiment methods of obtaining a binder based on the livestock enterprises waste, of forming binder with filler (sawdust, coal waste); of pyrogenetic processing to obtain a sorbent are described. Possible options for the introduction of magnetite (a magnetic component) in the composition of the oil sorbent are considered: on the surface, in the volume of the granule and the magnetite core. In the course of the work it was found that the optimum content of coal dust in the sorbent granules is 75% by weight, and the most effective way of obtaining the magnetic sorbent is to apply the carbon material directly to the "core" of magnetite. However, in this case, the problem of finding an effective binder for magnetite arises. The option of applying magnetite on the surface of a carbon sorbent is not effective. Thus, at present, we use a mixture of coal waste, which binds to the uniform distribution of magnetite in the volume. The developed magnetic sorbents can be used in various weather conditions, including strong winds and icing of water bodies, as well as for small and medium currents.

  8. Sorption of Aromatic Compounds with Copolymer Sorbent Materials Containing β-Cyclodextrin

    Directory of Open Access Journals (Sweden)

    Lee D. Wilson

    2011-08-01

    Full Text Available Urethane copolymer sorbent materials that incorporate β-cyclodextrin (CD have been prepared and their sorption properties with chlorinated aromatic compounds (i.e., pentachlorophenol, 2,4-dichlorophenol and 2,4-dichlorophenoxy acetic acid have been evaluated. The sorption properties of granular activated carbon (GAC were similarly compared in aqueous solution at variable pH conditions. The sorbents displayed variable BET surface areas as follows: MDI-X copolymers (< 101 m2/g, CDI-X copolymers (< 101 m2/g, and granular activated carbon (GAC ~103 m2/g. The sorption capacities for the copolymers sorbents are listed in descending order, as follows: GAC > CDI-3 copolymer ≈ MDI-3 copolymer. The sorption capacity for the aromatic adsorbates with each sorbent are listed in descending order, as follows: 2,4-dichlorophenol > 2,4-dichlorophenoxy acetic acid > pentachlorophenol. In general, the differences in the sorption properties of the copolymer sorbents with the chlorinated organics were related to the following factors: (i surface area of the sorbent; (ii CD content and accessibility; and (iii and the chemical nature of the sorbent material.

  9. Sorption of agrochemical model compounds by sorbent materials containing beta-cyclodextrin.

    Science.gov (United States)

    Wilson, Lee D; Mohamed, Mohamed H; Guo, Rui; Pratt, Dawn Y; Kwon, Jae Hyuck; Mahmud, Sarker T

    2010-04-01

    Polymeric sorbent materials that incorporate beta-cyclodextrin (CD) have been prepared and their sorption behavior toward two model agrochemical contaminant compounds, p-nitrophenol (PNP) and methyl chloride examined. The sorption of PNP was studied in aqueous solution using ultraviolet-visible (UV-Vis) spectroscopy, whereas the sorption of methyl chloride from the gas phase was studied using a Langmuir adsorption method. The sorption results for PNP in solution were compared between granular activated carbon (GAC), modified GAC, CD copolymers, and CD-based mesoporous silica hybrid materials. Nitrogen porosimetry at 77 K was used to estimate the surface area and pore structure properties of the sorbent materials. The sorbents displayed variable surface areas as follows: copolymers (36.2-157 m(2)/g), CD-silica materials (307-906 m(2)/g), surface modified GAC (657 m(2)/g), and granular activated carbon (approximately 10(3) m(2)/g). The sorption capacities for PNP and methyl chloride with the different sorbents are listed in descending order as follows: GAC > copolymers > surface modified GAC > CD-silica hybrid materials. In general, the differences in the sorption properties of the sorbents were related to the following: (i) surface area of the sorbent, (ii) CD content and accessibility, (iii) and the chemical nature of the sorbent material.

  10. Sorption of Aromatic Compounds with Copolymer Sorbent Materials Containing β-Cyclodextrin.

    Science.gov (United States)

    Wilson, Lee D; Mohamed, Mohamed H; Berhaut, Christopher L

    2011-08-29

    Urethane copolymer sorbent materials that incorporate β-cyclodextrin (CD) have been prepared and their sorption properties with chlorinated aromatic compounds (i.e., pentachlorophenol, 2,4-dichlorophenol and 2,4-dichlorophenoxy acetic acid) have been evaluated. The sorption properties of granular activated carbon (GAC) were similarly compared in aqueous solution at variable pH conditions. The sorbents displayed variable BET surface areas as follows: MDI-X copolymers (granular activated carbon (GAC ~10³ m²/g). The sorption capacities for the copolymers sorbents are listed in descending order, as follows: GAC > CDI-3 copolymer ≈ MDI-3 copolymer. The sorption capacity for the aromatic adsorbates with each sorbent are listed in descending order, as follows: 2,4-dichlorophenol > 2,4-dichlorophenoxy acetic acid > pentachlorophenol. In general, the differences in the sorption properties of the copolymer sorbents with the chlorinated organics were related to the following factors: (i) surface area of the sorbent; (ii) CD content and accessibility; and (iii) and the chemical nature of the sorbent material.

  11. Evaluation of silk-floss fiber and dog fur as sorbent materials for the petroleum sector

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Lucas P. dos [Universidade Federal do Parana (PGMec/UFPR), Curitiba, PR (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Dubiella, Juliana [Universidade Federal do Parana (DEMEC/UFPR), Curitiba, PR (Brazil). Dept. de Engenharia Mecanica. Programa Institucional de Bolsas de Iniciacao Cientifica; Perotta, Larissa [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Programa Interdisciplinar em Engenharia de Petroleo e Gas Natural; Satyanarayana, Kestur G. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Quimica; Flores-Sahagun, Thais Sydenstricker [Universidade Federal do Parana (DEMEC/UFPR), Curitiba, PR (Brazil). Dept. de Engenharia Mecanica

    2009-07-01

    In this study silk-floss and dog fur were tested as sorbent materials for oils and the results were compared with peat, a commercial sorbent. Sorption tests were carried out in dry and aqueous systems, with and without stirring for different periods of time (5-1440 min). Density, hydrophobicity, buoyancy and water uptake by the fibers of the impregnated sorbents have been determined. The use of silk-floss and dog fur was also tested in columns to purify water containing toluene, benzene, motor oil or sunflower oil. Breakthrough curves during 120 min were drawn for each material with the samples (oily water or water containing benzene or toluene) and were analyzed by ultraviolet spectroscopy. It was concluded that the silk-floss is the best sorbent material (65.3 g oil/g sorbent) followed by the dog fur (34.6 g oil/g sorbent) and peat (19.5 g oil/g sorbent), for sorption time of 1 h in dynamic condition. The efficiency of the pollutant removal from water with the use of adsorption columns was high for both materials although the use of dog fur was preferable because of the slight superiority in efficiency compared to silk-floss and also, due to the easier packing of the dog fur in the column. (author)

  12. Development of the advanced coolside sorbent injection process for SO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Withum, J.A.; Maskew, J.T.; Rosenhoover, W.A. [Consol, Inc., Library, PA (United States)] [and others

    1995-11-01

    The goal of this work was to develop a low-capital-cost process capable of over 90% SO{sub 2} removal as an economically attractive option for compliance with the Clean Air Act. The Advanced Coolside Process uses a contactor to simultaneously remove fly ash and saturate the flue gas with water, followed by sorbent injection into the highly humid flue gas and collection of the sorbent by the existing particulate collector High sorbent utilization is achieved by sorbent recycle. The original performance targets of 90% SO{sub 2} removal and 60% sorbent utilization were exceeded in 1000 acfm pilot plant operations using commercial hydrated lime as the only sorbent. Process optimization simplified the process equipment, resulting in significant cost reduction. Recent accomplishments include completion of equipment testing and sorbent optimization, a waste management study, and a long-term performance test. An economic evaluation for the optimized process projects capital costs 55% to 60 % less than those of limestone forced oxidation wet FGD. The projected levelized control cost is 15% to 35% lower than wet FGD (25% lower for a 260 MWe plant burning a 2.5% sulfur coal), depending on plant size and coal sulfur content.

  13. Highly stable and regenerable Mn-based/SBA-15 sorbents for desulfurization of hot coal gas

    International Nuclear Information System (INIS)

    Zhang, F.M.; Liu, B.S.; Zhang, Y.; Guo, Y.H.; Wan, Z.Y.; Subhan, Fazle

    2012-01-01

    Highlights: ► A series of mesoporous Cu x Mn y O z /SBA-15 sorbents were fabricated for hot coal gas desulfurization. ► 1Cu9Mn/SBA-15 sorbent with high breakthrough sulfur capacity is high stable and regenerable. ► Utilization of SBA-15 constrained the sintering and pulverization of sorbents. - Abstract: A series of mesoporous xCuyMn/SBA-15 sorbents with different Cu/Mn atomic ratios were prepared by wet impregnation method and their desulfurization performance in hot coal gas was investigated in a fixed-bed quartz reactor in the range of 700–850 °C. The successive nine desulfurization–regeneration cycles at 800 °C revealed that 1Cu9Mn/SBA-15 presented high performance with durable regeneration ability due to the high dispersion of Mn 2 O 3 particles incorporated with a certain amount of copper oxides. The breakthrough sulfur capacity of 1Cu9Mn/SBA-15 observed 800 °C is 13.8 g S/100 g sorbents, which is remarkably higher than these of 40 wt%LaFeO 3 /SBA-15 (4.8 g S/100 g sorbents) and 50 wt%LaFe 2 O x /MCM-41 (5.58 g S/100 g sorbents) used only at 500–550 °C. This suggested that the loading of Mn 2 O 3 active species with high thermal stability to SBA-15 support significantly increased sulfur capacity at relatively higher sulfidation temperature. The fresh and used xCuyMn/SBA-15 sorbents were characterized by means of BET, XRD, XPS, XAES, TG/DSC and HRTEM techniques, confirmed that the structure of the sorbents remained intact before and after hot coal gas desulfurization.

  14. Understanding Ethical Issues of Research Participation from the Perspective of Participating Children and Adolescents: A Systematic Review

    Science.gov (United States)

    Broome, Marion E.

    2017-01-01

    Background The past twenty years have seen distinct shifts in the way the participation of children and adolescents in research is viewed. This has been emphasized by the growing pediatric research enterprise. Additional information on children’s and adolescents’ experiences during research participation is needed to better inform researchers on the ethical conduct of research with this vulnerable population. Aims The objective of this analysis was to examine ethical issues in research with children and adolescents from their perspective as participants, including: assent, parental consent, risk perception, impact of research participation, and incentives. Methods This systematic review was conducted per the Long et al. framework by means of an iterative searching process. Using the key words ‘research ethics’ and ‘child or pediatric or adolescent’, PubMed, CINAHL, and EBSCOhost databases were searched to identify articles. Limitations placed on the original searches were: English language, year of publication between 2003–2014, humans, abstract available, and age birth–18 years. Findings Twenty-three empiric studies were identified and formed the sample. Included studies represented a diverse range of areas of research, methods, settings, sample demographics, authors, and journals. Discussion Even young children demonstrated the ability to understand essential elements of research, although there is variability in children’s level of understanding. Trust was a significant contributing factor to children’s and adolescents’ participation in research, and also shaped their assessments of risk. Research participation was mainly beneficial for children and adolescents. Incentives were mainly viewed positively, although concerns of possible undue influence were expressed. Linking Evidence to Action This systematic review highlights the importance of including the perspectives of children and adolescents and provides researchers and nurse clinicians

  15. Application of TIO2 as A sorbent for radioactive waste

    International Nuclear Information System (INIS)

    Zamroni, H.; Las, T.; Kamarz, H.

    1997-01-01

    The sorption properties of the neodymium has been studied by using TiO 2 sorbent. The experiment was carried out by batch methods to investigate the kinetic sorption, effect of pH and effect of NaNO 3 concentration in the solution. Neodymium uses for a model of trivalent actinide treated by TiO 2 which was known as materials having high thermal and radiation stabilities as well as potentially used for immobilization of waste with cement or vitrification. the results show that the optimum of kinetic sorption was obtained after one day experiment to reach the equilibrium in sorption on pH 4, and the increasing of NaNO 3 concentrations will increase the sorption of neodymium in solution (author)

  16. Phosphorus organic extragents and sorbents of radioactive a heavy metals

    International Nuclear Information System (INIS)

    Trofimov, B.A.; Gusarova, N.K.; Malysheva, S.F.; Sukhov, B.G.

    2002-01-01

    A fundamentally new method for activation of phosphorus in heterogenous super-base media including the conditions of mechanical, ultrasonic and X-ray activation, opening up a new way to C-P bond formation is developed. The method is opens principally new possibilities for direct atom-economic synthesis of previously unknown or difficult to obtain organophosphorus compounds (primary, secondary, tertiary phosphines and phosphine oxides) from elemental phosphorus and orga-nyl halides, electrophilic alkenes, acetylenes and oxiranes. Thus, the phosphothion and phosphorylation of organic compounds with elemental phosphorus, phosphines and phosphine oxides opens the principal new approach to the synthesis of specific and selective extra-gents, sorbents and complex-forming agents which can be used in the processes of purification and disinfecting of soil and water from radioactive and heavy metals

  17. Regenerable immobilized aminosilane sorbents for carbon dioxide capture applications

    Science.gov (United States)

    Gay, McMahan; Choi, Sunho; Jones, Christopher W

    2014-09-16

    A method for the separation of carbon dioxide from ambient air and flue gases is provided wherein a phase separating moiety with a second moiety are simultaneously coupled and bonded onto an inert substrate to create a mixture which is subsequently contacted with flue gases or ambient air. The phase-separating moiety is an amine whereas the second moiety is an aminosilane, or a Group 4 propoxide such as titanium (IV) propoxide (tetrapropyl orthotitanate, C.sub.12H.sub.28O.sub.4Ti). The second moiety makes the phase-separating moiety insoluble in the pores of the inert substrate. The new sorbents have a high carbon dioxide loading capacity and considerable stability over hundreds of cycles. The synthesis method is readily scalable for commercial and industrial production.

  18. Hot fuel gas dedusting after sorbent-based gas cleaning

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    Advanced power generation technologies, such as Air Blown Gasification Cycle (ABGC), require gas cleaning at high temperatures in order to meet environmental standards and to achieve high thermal efficiencies. The primary hot gas filtration process, which removes particulates from the cooled raw fuel gas at up to 600{degree}C is the first stage of gas cleaning prior to desulphurization and ammonia removal processes. The dust concentration in the fuel gas downstream of the sorbent processes would be much lower than for the hot gas filtration stage and would have a lower sulphur content and possibly reduced chlorine concentration. The main aim of this project is to define the requirements for a hot gas filter for dedusting fuel gas under these conditions, and to identify a substantially simpler and more cost effective solution using ceramic or metal barrier filters.

  19. Efficient CO2 sorbents based on silica foam with ultra-large mesopores

    KAUST Repository

    Qi, Genggeng; Fu, Liling; Choi, Brian Hyun; Giannelis, Emmanuel P.

    2012-01-01

    A series of high-capacity, amine impregnated sorbents based on a cost-effective silica foam with ultra-large mesopores is reported. The sorbents exhibit fast CO2 capture kinetics, high adsorption capacity (of up to 5.8 mmol g-1 under 1 atm of dry CO2), as well as good stability over multiple adsorption-desorption cycles. A simple theoretical analysis is provided relating the support structure to sorbent performance. © 2012 The Royal Society of Chemistry.

  20. Development of a Microwave Regenerative Sorbent-Based Hydrogen Purifier

    Science.gov (United States)

    Wheeler, Richard R., Jr.; Dewberry, Ross H.; McCurry, Bryan D.; Abney, Morgan B.; Greenwood, Zachary W.

    2016-01-01

    This paper describes the design and fabrication of a Microwave Regenerative Sorbent-based Hydrogen Purifier (MRSHP). This unique microwave powered technology was developed for the purification of a hydrogen stream produced by the Plasma Pyrolysis Assembly (PPA). The PPA is a hydrogen recovery (from methane) post processor for NASA's Sabatier-based carbon dioxide reduction process. Embodied in the Carbon dioxide Reduction Assembly (CRA), currently aboard the International Space Station (ISS), the Sabatier reaction employs hydrogen to catalytically recover oxygen, in the form of water, from respiratory carbon dioxide produced by the crew. This same approach is base-lined for future service in the Air Revitalization system on extended missions into deep space where resupply is not practical. Accordingly, manned exploration to Mars may only become feasible with further closure of the air loop as afforded by the greater hydrogen recovery permitted by the PPA with subsequent hydrogen purification. By utilizing the well-known high sorbate loading capacity of molecular sieve 13x, coupled with microwave dielectric heating phenomenon, MRSHP technology is employed as a regenerative filter for a contaminated hydrogen gas stream. By design, freshly regenerated molecular sieve 13x contained in the MRSHP will remove contaminants from the effluent of a 1-CM scale PPA for several hours prior to breakthrough. By reversing flow and pulling a relative vacuum the MRSHP prototype then uses 2.45 GHz microwave power, applied through a novel coaxial antenna array, to rapidly heat the sorbent bed and drive off the contaminants in a short duration vacuum/thermal contaminant desorption step. Finally, following rapid cooling via room temperature cold plates, the MRSHP is again ready to serve as a hydrogen filter.

  1. Understanding what helps or hinders asthma action plan use: a systematic review and synthesis of the qualitative literature.

    Science.gov (United States)

    Ring, Nicola; Jepson, Ruth; Hoskins, Gaylor; Wilson, Caroline; Pinnock, Hilary; Sheikh, Aziz; Wyke, Sally

    2011-11-01

    To understand better what helps and/or hinders asthma action plan use from the professionals and patients/carers perspective. Systematic review and qualitative synthesis (using meta-ethnography). Nineteen studies (20 papers) were included in an analysis of patients/carers' and professionals' views. Seven main influences on action plan implementation were identified including perceived un-helpfulness and irrelevance of the plans. Translation and synthesis of the original authors' interpretations suggested that action plan promotion and use was influenced by professional and patient/carers' asthma beliefs and attitudes and patient/carer experiences of managing asthma. Action plan use is hindered because professionals and patients/carers have different explanatory models of asthma, its management and their respective roles in the management process. Patients/carers, based on their experiential knowledge of their condition, perceive themselves as capable, effective in managing their asthma, but health professionals do not always share this view. Professionally provided medically focused action plans that do not 'fit' with and incorporate the patients'/carers' views of asthma, and their management strategies, will continue to be under-utilised. Professionals need to develop a more patient-centred, partnership-based, approach to the joint development and review of action plans, recognising the experiential asthma knowledge of patients/carers. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  2. Current concepts on burn wound conversion – a review of recent advances in understanding the secondary progressions of burns

    Science.gov (United States)

    Salibian, Ara A.; Del Rosario, Angelica Tan; De Almeida Moura Severo, Lucio; Nguyen, Long; Banyard, Derek A.; Toranto, Jason D.; Evans, Gregory R.D.; Widgerow, Alan D.

    2016-01-01

    Burn wound conversion describes the process by which superficial partial thickness burns convert into deeper burns necessitating surgical intervention. Fully understanding and thus controlling this phenomenon continues to defy burn surgeons. However, potentially guiding burn wound progression so as to obviate the need for surgery while still bringing about healing with limited scarring is the major unmet challenge. Comprehending the pathophysiologic background contributing to deeper progression of these burns is an essential prerequisite to planning any intervention. In this study, a review of articles examining burn wound progression over the last five years was conducted to analyze trends in recent burn progression research, determine changes in understanding of the pathogenesis of burn conversion, and subsequently examine the direction for future research in developing therapies. The majority of recent research focuses on applying therapies from other disease processes to common underlying pathogenic mechanisms in burn conversion. While ischemia, inflammation, and free oxygen radicals continue to demonstrate a critical role in secondary necrosis, novel mechanisms such as autophagy have also been shown to contribute affect significantly burn progression significantly. Further research will have to determine whether multiple mechanisms should be targeted when developing clinical therapies. PMID:26787127

  3. User testing and stakeholder feedback contributed to the development of understandable and useful Summary of Findings tables for Cochrane reviews.

    Science.gov (United States)

    Rosenbaum, Sarah E; Glenton, Claire; Nylund, Hilde Kari; Oxman, Andrew D

    2010-06-01

    To develop a Summary of Findings (SoF) table for use in Cochrane reviews that is understandable and useful for health professionals, acceptable to Cochrane Collaboration stakeholders, and feasible to implement. We gathered stakeholder feedback on the format and content of an SoF table from an advisory group of more than 50 participants and their constituencies through e-mail consultations. We conducted user tests using a think-aloud protocol method, collecting feedback from 21 health professionals and researchers in Norway and the UK. We analyzed the feedback, defined problem areas, and generated new solutions in brainstorming workshops. Stakeholders were concerned about precision in the data representation and about production feasibility. User testing revealed unexpected comprehension problems, mainly confusion about what the different numbers referred to (class reference). Resolving the tension between achieving table precision and table simplicity became the main focus of the working group. User testing led to a table more useful and understandable for clinical audiences. We arrived at an SoF table that was acceptable to the stakeholders and in principle feasible to implement technically. Some challenges remain, including presenting continuous outcomes and technical/editorial implementation.

  4. Supported modified hydrotalcites as sorbent for CO2 capture

    Energy Technology Data Exchange (ETDEWEB)

    Meis, N.

    2010-02-15

    The average concentration of CO2 in the atmosphere has been increasing since the start of the industrial revolution in the 18th century from 280 ppm to 385 ppm nowadays, and continues to increase because of the enormous human usage of fossil fuels (oil, gas, coal). This can strongly affect the climate, causing the Earth's surface to warm up, the so called 'amplified greenhouse effect'. To alleviate these environmental concerns regarding the current CO2 emissions into the atmosphere, Carbon Capture and Storage (CCS) is investigated as one of the possible routes. Due to the acidic character of CO2, basic oxides are expected to be suitable sorbents. Hydrotalcite, a natural clay, is specifically suitable for pre-combustion capture (250- 400{sup o}C), due to its acceptable sorption capacity and facile regeneration. The influence of lateral platelet size ({+-}40 nm - 2 {mu}m), the use of a support (carbon nanofibers, CNF) and addition of a promoter (alkali carbonate: K{sub 2}CO{sub 3}/Na{sub 2}CO{sub 3}) on the CO2 capture properties of HT was investigated. There was no significant difference in the CO2 sorption capacities at 523K for all unsupported HTs, regardless the platelet size of the HT precursor ({+-}0.1 mmol.g{sup -1}). The use of activated, promoted (alkali carbonate) hydrotalcites showed a much higher capacity ({+-}0.3 mmol.g{sup -1}) at 523K. In addition, the capacities of the activated supported HT at 523K were significantly increased compared to the activated unsupported HT (1.3-2.5 mmol.g{sup -1} HT). The alkali-loaded supported HTs showed capacities slightly higher than the capacity of supported unpromoted HT. The increase in capacity for the promoted and/or supported HTs points to a higher concentration of defects (low-coordination of oxygen sites) on the surface of the activated (alkali-)loaded HTs compared to the unloaded and unsupported HT. The higher concentration of adsorption for the promoted (supported) HTs, might be caused by the

  5. Long-Term Stability Testing Results Using Surrogates And Sorbents For Savannah River Site Organic And Aqueous Wastestreams - 10016

    International Nuclear Information System (INIS)

    Burns, H.

    2009-01-01

    The U.S. Department of Energy (DOE) has tasked MSE Technology Applications, Inc. (MSE) with evaluating the long-term stability of various commercially available sorbent materials to solidify two organic surrogate wastestreams (both volatile and nonvolatile), a volatile organic surrogate with a residual aqueous phase, an aqueous surrogate, and an aqueous surrogate with a residual organic phase. The Savannah River Site (SRS) Legacy and F-Canyon plutonium/uranium extraction (PUREX) process waste surrogates constituted the volatile organic surrogates, and various oils constituted the nonvolatile organic surrogates. The aqueous surrogates included a rainwater surrogate and an aqueous organic surrogate. MSE also evaluated the PUREX surrogate with a residual aqueous component with and without aqueous type sorbent materials. Solidification of the various surrogate wastestreams listed above was performed from 2004 to 2006 at the MSE Test Facility located in Butte, Montana. This paper summarizes the comparison of the initial liquid release test (LRT) values with LRT results obtained during subsequent sampling events in an attempt to understand and define the long-term stability characteristics for the solidified wastestreams.

  6. Towards an understanding of the role of clay minerals in crude oil formation, migration and accumulation

    Science.gov (United States)

    Wu, Lin Mei; Zhou, Chun Hui; Keeling, John; Tong, Dong Shen; Yu, Wei Hua

    2012-12-01

    This article reviews progress in the understanding of the role of clay minerals in crude oil formation, migration and accumulation. Clay minerals are involved in the formation of kerogen, catalytic cracking of kerogen into petroleum hydrocarbon, the migration of crude oil, and the continued change to hydrocarbon composition in underground petroleum reservoirs. In kerogen formation, clay minerals act as catalysts and sorbents to immobilize organic matter through ligand exchange, hydrophobic interactions and cation bridges by the mechanisms of Maillard reactions, polyphenol theory, selective preservation and sorptive protection. Clay minerals also serve as catalysts in acid-catalyzed cracking of kerogen into petroleum hydrocarbon through Lewis and Brønsted acid sites on the clay surface. The amount and type of clay mineral affect the composition of the petroleum. Brønsted acidity of clay minerals is affected by the presence and state of interlayer water, and displacement of this water is a probable driver in crude oil migration from source rocks. During crude oil migration and accumulation in reservoirs, the composition of petroleum is continually modified by interaction with clay minerals. The clays continue to function as sorbents and catalysts even while they are being transformed by diagenetic processes. The detail of chemical interactions and reaction mechanisms between clay minerals and crude oil formation remains to be fully explained but promises to provide insights with broader application, including catalytic conversion of biomass as a source of sustainable energy into the future.

  7. High efficiency nanocomposite sorbents for CO2 capture based on amine-functionalized mesoporous capsules

    KAUST Repository

    Qi, Genggeng; Wang, Yanbing; Estevez, Luis; Duan, Xiaonan; Anako, Nkechi; Park, Ah-Hyung Alissa; Li, Wen; Jones, Christopher W.; Giannelis, Emmanuel P.

    2011-01-01

    A novel high efficiency nanocomposite sorbent for CO2 capture has been developed based on oligomeric amine (polyethylenimine, PEI, and tetraethylenepentamine, TEPA) functionalized mesoporous silica capsules. The newly synthesized sorbents exhibit extraordinary capture capacity up to 7.9 mmol g-1 under simulated flue gas conditions (pre-humidified 10% CO 2). The CO2 capture kinetics were found to be fast and reached 90% of the total capacities within the first few minutes. The effects of the mesoporous capsule features such as particle size and shell thickness on CO2 capture capacity were investigated. Larger particle size, higher interior void volume and thinner mesoporous shell thickness all improved the CO2 capacity of the sorbents. PEI impregnated sorbents showed good reversibility and stability during cyclic adsorption-regeneration tests (50 cycles). © 2011 The Royal Society of Chemistry.

  8. Sorbents for waste water purification from radionuclides and other toxic substances

    International Nuclear Information System (INIS)

    Maddalone, R.F.; MakKlenason, L.Ts.

    1996-01-01

    The TRW firm (USA) developed the system for sorption and disposal of radionuclides, heavy metals and organic substances, based on utilization of carbon sorbents. The sorbent is produced through processing natural coal by alkali-salt solution and has a large specific pores surface (up to 1000 m 2 /g). The sorbent carboxyl ionogenic groups are able of absorbing heavy metals cations from waste waters. Sorption by uranium constituted 30 mg/l. The sorbent with absorbed substances may be burnt (it contains no sulfur) or delivered for vitrification. The volume of disposed materials constitutes in comparison with existing techniques for uranium isotopes 420000 : 1. The costs are reduced up to 0.26 doll/m 2 of reprocessed water. 2 refs., 2 figs., 4 tabs

  9. Application of magnetic sorbent in the removal of cadmium from soils

    Directory of Open Access Journals (Sweden)

    Michal Lovás

    2006-12-01

    Full Text Available A contamination of soil by heavy metals is a common problem at many metalliferous mining sites. There are various treatment processes for the cleanup of soil contaminated with heavy metals. A method designed for the decontamination of soil polluted by Cd is described. The method utilizes a magnetic sorbent – sludges from the hydrometallurgic processing of nickel mineral, activated by milling. The influence of sorbent concentration, pH and microwave energy on the sorption capacity and content of Cd ions in a soil was studed. The effectiveness of Cd desorption from the soil was 75 %, the maximal sorption capacity of sorbent was 9,8 mg/g. The content of Cd in water is function of pH and the concentration of sorbent. The influence of microwave energy (90 W was negligible.

  10. Experimental investigation of various vegetable fibers as sorbent materials for oil spills.

    Science.gov (United States)

    Annunciado, T R; Sydenstricker, T H D; Amico, S C

    2005-11-01

    Oil spills are a global concern due to their environmental and economical impact. Various commercial systems have been developed to control these spills, including the use of fibers as sorbents. This research investigates the use of various vegetable fibers, namely mixed leaves residues, mixed sawdust, sisal (Agave sisalana), coir fiber (Cocos nucifera), sponge-gourd (Luffa cylindrica) and silk-floss as sorbent materials of crude oil. Sorption tests with crude oil were conducted in deionized and marine water media, with and without agitation. Water uptake by the fibers was investigated by tests in dry conditions and distillation of the impregnated sorbent. The silk-floss fiber showed a very high degree of hydrophobicity and oil sorption capacity of approximately 85goil/g sorbent (in 24hours). Specific gravity measurements and buoyancy tests were also used to evaluate the suitability of these fibers for the intended application.

  11. Rubidium extraction using an organic polymer encapsulated potassium copper hexacyanoferrate sorbent

    KAUST Repository

    Naidu, Gayathri; Loganathan, Paripurnanda; Jeong, Sanghyun; Johir, Md.Abu Hasan; To, Vu Hien Phuong; Kandasamy, Jaya; Vigneswaran, Saravanamuthu

    2016-01-01

    Sea water reverse osmosis (SWRO) brine contains significant quantity of Rb. As an economically valuable metal, extracting Rb using a suitable and selective extraction method would be beneficial. An inorganic sorbent, copper based potassium

  12. Experimental investigation of various vegetable fibers as sorbent materials for oil spills

    Energy Technology Data Exchange (ETDEWEB)

    Annunciado, T.R.; Sydenstricker, T.H.D.; Amico, S.C. [Federal University of Parana, Curitiba, (Brazil). Department of Mechanical Engineering

    2005-11-15

    Oil spills are a global concern due to their environmental and economical impact. various commercial systems have been developed to control these spills, including the use of fibers as sorbents. This research investigates the use of various vegetable fibers, namely mixed leaves residues, mixed sawdust, sisal (Agave sisalana), coir fiber (Cocos nucifera), sponge-gourd (Luffa cylindrica) and silk-floss as sorbent materials of crude oil. Sorption tests with crude oil were conducted in deionized and marine water media, with and without agitation. Water uptake by the fibers was investigated by tests in dry conditions and distillation of the impregnated sorbent. The silk-floss fiber showed a very high degree of hydrophobicity and oil sorption capacity of approximately 85 g oil/g sorbent (in 24 hours). Specific gravity measurements and buoyancy tests were also used to evaluate the suitability of these fibers for the intended application. (author)

  13. Arsenic removal from aqueous solutions by sorption onto zirconium- and titanium-modified sorbents

    Directory of Open Access Journals (Sweden)

    Ignjatović Ljubiša

    2011-01-01

    Full Text Available Arsenic reduction in drinking water can include treatment by adsorption, switching to alternative water sources, or blending with water that has a lower arsenic concentration. Commercial sorbents MTM, Greensand and BIRM (Clack Corporation were modified with zirconium and titanium after activation. The modifications were performed with titanium tetrachloride and zirconium tetrachloride. The modified sorbents were dried at different temperatures. The sorption of arsenate and arsenite dissolved in drinking water (200μg L-1 onto the sorbents were tested using a batch procedure. After removal of the sorbent, the concentration of arsenic was determined by HG-AAS. Zirconium-modified BIRM showed the best performance for the removal of both arsenite and arsenate. Modification of the greensand did not affect arsenic sorption ability. Zirconium-modified BIRM diminished the concentration of total As to below 5 μg L-1.

  14. Evaluation of Solid Sorbents as a Retrofit Technology for CO2 Capture

    Energy Technology Data Exchange (ETDEWEB)

    Sjostrom, Sharon [Ada-Es, Inc., Highlands Ranch, CO (United States)

    2016-06-02

    ADA completed a DOE-sponsored program titled Evaluation of Solid Sorbents as a Retrofit Technology for CO2 Capture under program DE-FE0004343. During this program, sorbents were analyzed for use in a post-combustion CO2 capture process. A supported amine sorbent was selected based upon superior performance to adsorb a greater amount of CO2 than the activated carbon sorbents tested. When the most ideal sorbent at the time was selected, it was characterized and used to create a preliminary techno-economic analysis (TEA). A preliminary 550 MW coal-fired power plant using Illinois #6 bituminous coal was designed with a solid sorbent CO2 capture system using the selected supported amine sorbent to both facilitate the TEA and to create the necessary framework to scale down the design to a 1 MWe equivalent slipstream pilot facility. The preliminary techno-economic analysis showed promising results and potential for improved performance for CO2 capture compared to conventional MEA systems. As a result, a 1 MWe equivalent solid sorbent system was designed, constructed, and then installed at a coal-fired power plant in Alabama. The pilot was designed to capture 90% of the CO2 from the incoming flue gas at 1 MWe net electrical generating equivalent. Testing was not possible at the design conditions due to changes in sorbent handling characteristics at post-regenerator temperatures that were not properly incorporated into the pilot design. Thus, severe pluggage occurred at nominally 60% of the design sorbent circulation rate with heated sorbent, although no handling issues were noted when the system was operated prior to bringing the regenerator to operating temperature. Testing within the constraints of the pilot plant resulted in 90% capture of the incoming CO2 at a flow rate equivalent of 0.2 to 0.25 MWe net electrical generating equivalent. The reduction in equivalent flow rate at 90% capture was

  15. Chitosan-ferrocyanide sorbent for Cs-137 removal from mineralized alkaline media

    Energy Technology Data Exchange (ETDEWEB)

    Egorin, Andrei [Far Eastern Federal Univ., Vladivostok (Russian Federation); Institute of Chemistry FEBRAS, Vladivostok (Russian Federation); Ozyorsk Technical Institute MEPHI, Ozersk (Russian Federation); Tokar, Eduard [Far Eastern Federal Univ., Vladivostok (Russian Federation); Zemskova, Larisa [Institute of Chemistry FEBRAS, Vladivostok (Russian Federation)

    2016-11-01

    An organomineral sorbent based on mixed nickel-potassium ferrocyanide and chitosan to be used in removal of Cs-137 radionuclide from highly mineralized media with high pH has been fabricated. The synthesized sorbent was applied to remove Cs-137 from model solutions under static and dynamic conditions. The effects of contact time, pH, and presence of sodium ions and complexing agents in the process of Cs-137 removal have been investigated. The sorbent is distinguished by increased stability to the impact of alkaline media containing complexing agents, whereas the sorbent capacity in solutions with pH 11 exceeds 1000 bed volumes with the Cs-137 removal efficiency higher than 95%.

  16. 21 CFR 876.5600 - Sorbent regenerated dialysate delivery system for hemodialysis.

    Science.gov (United States)

    2010-04-01

    ... dialyzer. The device is used with the extracorporeal blood system and the dialyzer of the hemodialysis... dialysate conditions. The sorbent cartridge may include absorbent, ion exchange and catalytic materials. (b...

  17. Application of fibrous complexing sorbents for trace elements preconcentration and separation

    International Nuclear Information System (INIS)

    Zakhartchenko, E.A.; Myasoedova, G.V.

    2003-01-01

    This article demonstrates the application of the 'filled' fibrous sorbents for preconcentration and separation of platinum metals, as well as heavy metals and radionuclides. The POLYORGS complexing sorbents and ion-exchangers were used as fillers. Dynamic preconcentration conditions should be set for complete sorption of the elements: diameter and mass of the sorbent disk or the column as well as flow rate of the solution. These conditions depend on specific features of materials to be analysed and the requirements of the experimental task or detection method. Extensive alteration of features as well as perfect kinetic properties and high selectivity of the 'filled' sorbents confirm their applicability for trace elements preconcentration and separation in technology and analytical chemistry. (authors)

  18. Zinc-oxide-based sorbents and processes for preparing and using same

    Science.gov (United States)

    Gangwal, Santosh Kumar; Turk, Brian Scott; Gupta, Raghubir Prasael

    2010-03-23

    Zinc oxide-based sorbents, and processes for preparing and using them are provided. The sorbents are preferably used to remove one or more reduced sulfur species from gas streams. The sorbents comprise an active zinc component, optionally in combination with one or more promoter components and/or one or more substantially inert components. The active zinc component is a two phase material, consisting essentially of a zinc oxide (ZnO) phase and a zinc aluminate (ZnAl.sub.2O.sub.4) phase. Each of the two phases is characterized by a relatively small crystallite size of typically less than about 500 Angstroms. Preferably the sorbents are prepared by converting a precursor mixture, comprising a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor, to the two-phase, active zinc oxide containing component.

  19. Tail gas treatment of SEWGS technology. Literature review on CO2 and H2S separation

    Energy Technology Data Exchange (ETDEWEB)

    Fabbri, E.N.; Van Dijk, H.A.J. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2011-12-15

    This literature review is the result of an investigation of the most important way to remove sulphur for the last decades. We will discuss Claus and Claus tail gas process options to solve the problem. Next to solutions which come from membranes, direct oxidation catalysis, from acid gas removal technology, sorbent technology, and liquid oxidation. Each field will be described and explained to understand in which way it could be suitable to separate CO2 and H2S and reach our goals with regard to CO2 transport and storage conditions. Finally, the target of this work will be to propose some interesting and promising solutions in view of future experiments.

  20. Hydroxyapatite-based sorbents: elaboration, characterization and application for the removal of catechol from the aqueous phase.

    Science.gov (United States)

    Sebei, Haroun; Pham Minh, Doan; Lyczko, Nathalie; Sharrock, Patrick; Nzihou, Ange

    2017-10-01

    Hydroxyapatite (HAP) is highly considered as good sorbent for the removal of metals from the aqueous phase. However, soluble metals co-exist with organic pollutants in wastewaters. But little work has been devoted to investigate the reactivity of HAP for the removal of organic compounds. The main objective of this work is to study the reactivity of HAP-based sorbents for the removal of catechol as a model organic pollutant from an aqueous solution. Thus, HAP sorbents were firstly synthesized using calcium carbonate and potassium dihydrogen phosphate under moderate conditions (25-80°C, atmospheric pressure). A zinc-doped HAP was also used as sorbent, which was obtained from the contact of HAP with an aqueous solution of zinc nitrate. All the sorbents were characterized by different standard physico-chemical techniques. The sorption of catechol was carried out in a batch reactor under stirring at room temperature and pressure. Zinc-doped HAP sorbent was found to be more reactive than non-doped HAP sorbents for the fixation of catechol. The highest sorption capacity was of 15 mg of C per gram of zinc-doped HAP sorbent. The results obtained suggest the reaction scheme of HAP sorbents with metals and organic pollutants when HAP sorbents were used for the treatment of complex wastewaters.

  1. Sorption of short-lived radionuclides in a layer of sorbent with spherical granules

    International Nuclear Information System (INIS)

    Karlin, Yu.V.

    1993-01-01

    Sorption methods have found wide application in the purification of liquid radioactive wastes. The working element in sorption methods for this purpose is usually a sorption column with a fixed layer of sorbent. Continuous-action equipment with a moving layer of sorbent is very seldom used. When a fixed layer of sorbent is used its wear and prolonged mixing in the sorption column are reduced to a minimum, and maximum purification is achieved due to the advantages of the dynamic method of sorption over the static method. The time of protective action of the sorbent layer is determined by the time taken for the radionuclide to pass through the sorption column, and for the majority of radionuclides is determined by numerous parameters, including the type of sorbent and radionuclide, the rate of flow through the sorbent, the size of the sorbent granules, etc. The physical and chemical aspects of this process have been investigated in detail, and numerous methods for modeling it mathematically have been developed and have been used to develop methods of designing sorption column apparatus. The specific nature of the radionuclides as unstable materials enables the hypothetical case of a open-quotes perpetualclose quotes sorption filter to be represented. In fact, to achieve this it is only necessary to assume that the half-life of the radionuclide is so small that the rate of decay of the radionuclide in the sorption column (both in the sorbed state and in the aqueous phase of the sorption layer) is equal to the rate that it is fed into the column in the flow of liquid radioactive waste. In this case the sorption front of the radionuclide in the column wall remains fixed after a certain initial period. In this paper, a mathematical model of such a hypothetical filter for the case of spherical sorbent granules is considered

  2. Silver nanoparticles embedded polymer sorbent for preconcentration of uranium from bio-aggressive aqueous media

    International Nuclear Information System (INIS)

    Das, Sadananda; Pandey, Ashok K.; Athawale, Anjali A.; Subramanian, M.; Seshagiri, T.K.; Khanna, Pawan K.; Manchanda, Vijay K.

    2011-01-01

    Adsorptive sorbent for bio-aggressive natural aqueous media like seawater was developed by one pot simultaneous synthesis of silver nanoparticles (Ag nps) and poly(ethylene glycol methacrylate phosphate) (PEGMP) by UV-initiator induced photo-polymerization. The photo-polymerization was carried out by irradiating N,N'-dimethylformamide (DMF) solution containing appropriate amounts of the functional monomer (ethylene glycol methacrylate phosphate), UV initiator (α,α'-dimethoxy-α-phenyl acetophenone), and Ag + ions with 365 nm UV light in a multilamps photoreactor. To increase mechanical strength, nano-composite sorbent (Ag-PEGMP) was also reinforced with thermally bonded non-woven poly(propylene) fibrous sheet. Transmission electron microscopy (TEM) of the nano-composite sorbent showed uniform distribution of spherical Ag nanoparticles with particles size ranging from 3 to 6 nm. The maximum amount of Ag 0 that could be anchored in the form of nanoparticles were 5 ± 1 and 10 ± 1 wt.% in self-supported PEGMP and poly(propylene) reinforced PEGMP matrices, respectively. Ag-PEGMP sorbent was found to be stable under ambient conditions for a period of six months. Ag-PEGMP composite sorbent did not exhibit growth at all after incubation with pre-grown Escherichia coli cells, and showed non-adherence of this bacteria to the composite. This indicated that composite sorbent has the bio-resistivity due to bacterial repulsion and bactericidal properties of Ag nanoparticles embedded in the PEGMP. Sorption of U(VI) in PEGMP and Ag-PEGMP nano-composite sorbents from well-stirred seawater was studied to explore the possibility of using it for uranium preconcentration from bio-aggressive aqueous streams. The nano-composite sorbent was used to preconcentrate U(VI) from a process aqueous waste stream.

  3. Mixed and Doped Solid Sorbents for CO2 Capture Applications

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Yuhua [National Energy Technology Lab. (NETL), Albany, OR (United States)

    2016-06-14

    The objectives of this presentation are to capture CO2 we need materials with optimal performance and low costs; establish a theoretical procedure to identify most potential candidates of CO2 solid sorbents from a large solid material databank; computational synthesis new materials to fit industrial needs; and explore the optimal working conditions for the promised CO2 solid sorbents, especially from room to warm T ranges with optimal energy usage.

  4. Sorption of Aromatic Compounds with Copolymer Sorbent Materials Containing β-Cyclodextrin

    OpenAIRE

    Wilson, Lee D.; Mohamed, Mohamed H.; Berhaut, Christopher L.

    2011-01-01

    Urethane copolymer sorbent materials that incorporate β-cyclodextrin (CD) have been prepared and their sorption properties with chlorinated aromatic compounds (i.e., pentachlorophenol, 2,4-dichlorophenol and 2,4-dichlorophenoxy acetic acid) have been evaluated. The sorption properties of granular activated carbon (GAC) were similarly compared in aqueous solution at variable pH conditions. The sorbents displayed variable BET surface areas as follows: MDI-X copolymers (< 101 m2/g), CDI-X cop...

  5. Theoretical Predictions of the thermodynamic Properties of Solid Sorbents Capture CO2 Applications

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Yuhua; Sorescu, Dan; Luebke David; Pennline, Henry

    2012-05-02

    We are establishing a theoretical procedure to identify most potential candidates of CO{sub 2} solid sorbents from a large solid material databank to meet the DOE programmatic goal for energy conversion; and to explore the optimal working conditions for the promising CO{sub 2} solid sorbents, especially from room to warm T ranges with optimal energy usage, used for both pre- and post-combustion capture technologies.

  6. Understanding Negative Self-Evaluations in Borderline Personality Disorder-a Review of Self-Related Cognitions, Emotions, and Motives.

    Science.gov (United States)

    Winter, Dorina; Bohus, Martin; Lis, Stefanie

    2017-03-01

    Self-conscious emotions, such as guilt, shame, or self-disgust, as well as self-related motives, such as self-enhancement or self-verification, influence how people perceive, evaluate, memorize, and respond to self-related information. They not only influence peoples' concepts of themselves but may also affect their behavior in social environments. In the current review, we describe alterations of self-related processing in borderline personality disorder (BPD). We chose BPD as an example of a mental disorder of which impairments in self-functioning and identity constitute a major feature. Since terminology used in clinical research on self-referential processing is diverse and often confusing, we start with reviewing some of the main concepts in this area of research using a conceptual framework provided from social psychology. Most studies on self-referential processing in BPD focused on descriptions of self-esteem and revealed a negative self-concept, particularly expressed by explicitly reported low self-esteem. Moreover, self-esteem is unstable in BPD and likely reactive to self-relevant cues. BPD patients are prone to negative emotions with respect to themselves, such as self-disgust and shame. First data point to altered self-related motives, too. In conclusion, although explicit self-esteem is widely studied as a global and trait-like feature of BPD, there is a strong lack of studies that take the complexity of the construct self-esteem into account. Further studies on alterations in self-related processes are required to deepen our understanding of impairments of the self-concept in BPD and enable the improvement of psychosocial therapeutic approaches.

  7. Understanding Outdoor Gyms in Public Open Spaces: A Systematic Review and Integrative Synthesis of Qualitative and Quantitative Evidence.

    Science.gov (United States)

    Lee, Janet Lok Chun; Lo, Temmy Lee Ting; Ho, Rainbow Tin Hung

    2018-03-25

    (1) Background: An outdoor gym (OG) is environmental infrastructure built in a public open space to promote structured physical activity. The provision of OGs is increasingly seen as an important strategy to realize public health agendas promoting habitual physical activity. A systematic review was conducted to synthesize characteristics of OG and OG users' experiences and perceptions in different cultural contexts; (2) Methods: Online searches of multidisciplinary databases were conducted in health, sport and recreation, and urban planning disciplines. Characteristics of OGs were synthesized by integrating evidence from quantitative, qualitative, and mix-methods studies. The experiences and perceptions of OG users from both qualitative data and survey responses were synthesized through framework analysis; (3) Results: Nine studies met the inclusion criteria (three quantitative studies, four mixed-methods studies, and two pure qualitative studies). None were excluded on the basis of quality. OGs mainly serve adult and older adult population groups. Their size, design, and instructional support vary across studies. The inclusion of functional types of equipment did not have a unified standard. Regarding experiences and perceptions of OGs, five major themes emerged: "health", "social connectedness", "affordable", "support", and "design and promotion"; (4) Conclusions: The OG characteristics synthesis guides the direction in further studies regarding exploration of design parameters. The qualitative and quantitative synthesis revealed that health was a central theme of users' experiences. OGs are also spaces where community-dwellers can find social connectedness while participating in structured physical activity at no cost. Findings from this review create knowledge support for OG as environmental infrastructure for further research and facilitate the understanding of users' experiences and perceptions of OGs in different cultural contexts.

  8. Understanding suicide risk within the Research Domain Criteria (RDoC) framework: A meta-analytic review.

    Science.gov (United States)

    Glenn, Catherine R; Kleiman, Evan M; Cha, Christine B; Deming, Charlene A; Franklin, Joseph C; Nock, Matthew K

    2018-01-01

    The field is in need of novel and transdiagnostic risk factors for suicide. The National Institute of Mental Health's Research Domain Criteria (RDoC) provides a framework that may help advance research on suicidal behavior. We conducted a meta-analytic review of existing prospective risk and protective factors for suicidal thoughts and behaviors (ideation, attempts, and deaths) that fall within one of the five RDoC domains or relate to a prominent suicide theory. Predictors were selected from a database of 4,082 prospective risk and protective factors for suicide outcomes. A total of 460 predictors met inclusion criteria for this meta-analytic review and most examined risk (vs. protective) factors for suicidal thoughts and behaviors. The overall effect of risk factors was statistically significant, but relatively small, in predicting suicide ideation (weighted mean odds ratio: wOR = 1.72; 95% CI: 1.59-1.87), suicide attempt (wOR = 1.66 [1.57-1.76), and suicide death (wOR = 1.41 [1.24-1.60]). Across all suicide outcomes, most risk factors related to the Negative Valence Systems domain, although effect sizes were of similar magnitude across RDoC domains. This study demonstrated that the RDoC framework provides a novel and promising approach to suicide research; however, relatively few studies of suicidal behavior fit within this framework. Future studies must go beyond the "usual suspects" of suicide risk factors (e.g., mental disorders, sociodemographics) to understand the processes that combine to lead to this deadly outcome. © 2017 Wiley Periodicals, Inc.

  9. Understanding Outdoor Gyms in Public Open Spaces: A Systematic Review and Integrative Synthesis of Qualitative and Quantitative Evidence

    Science.gov (United States)

    Lee, Janet Lok Chun; Lo, Temmy Lee Ting

    2018-01-01

    (1) Background: An outdoor gym (OG) is environmental infrastructure built in a public open space to promote structured physical activity. The provision of OGs is increasingly seen as an important strategy to realize public health agendas promoting habitual physical activity. A systematic review was conducted to synthesize characteristics of OG and OG users’ experiences and perceptions in different cultural contexts; (2) Methods: Online searches of multidisciplinary databases were conducted in health, sport and recreation, and urban planning disciplines. Characteristics of OGs were synthesized by integrating evidence from quantitative, qualitative, and mix-methods studies. The experiences and perceptions of OG users from both qualitative data and survey responses were synthesized through framework analysis; (3) Results: Nine studies met the inclusion criteria (three quantitative studies, four mixed-methods studies, and two pure qualitative studies). None were excluded on the basis of quality. OGs mainly serve adult and older adult population groups. Their size, design, and instructional support vary across studies. The inclusion of functional types of equipment did not have a unified standard. Regarding experiences and perceptions of OGs, five major themes emerged: “health”, “social connectedness”, “affordable”, “support”, and “design and promotion”; (4) Conclusions: The OG characteristics synthesis guides the direction in further studies regarding exploration of design parameters. The qualitative and quantitative synthesis revealed that health was a central theme of users’ experiences. OGs are also spaces where community-dwellers can find social connectedness while participating in structured physical activity at no cost. Findings from this review create knowledge support for OG as environmental infrastructure for further research and facilitate the understanding of users’ experiences and perceptions of OGs in different cultural contexts

  10. Towards a better understanding of caregiver distress in early psychosis: a systematic review of the psychological factors involved.

    Science.gov (United States)

    Jansen, Jens Einar; Gleeson, John; Cotton, Sue

    2015-02-01

    We sought to review empirical studies of psychological factors accounting for distress in caregivers of young people with early psychosis. Following the PRISMA guidelines, we included studies that empirically tested psychological models of caregiver distress in early psychosis by searching the following databases up until March 2014: PsycINFO, EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL). This was followed by additional manual searches of reference lists and relevant journals. The search identified 15 papers describing 13 studies together comprising 1056 caregivers of persons with early psychosis. The mean age of caregivers was 47.2years (SD=9.8), of whom 71.5% were female and 74.4% were parents. Nine different psychological variables were examined in the included studies, which were categorised in the following non-mutually exclusive groups: coping, appraisal/attribution and interpersonal response. There was considerable data to support the link between distress and psychological factors such as avoidant coping, appraisal and emotional over-involvement. However, the possibilities of drawing conclusions were limited by a number of methodological issues, including cross-sectional data, small sample sizes, confounding variables not being accounted for, and a wide variation in outcome measures. The strengths of the review were the systematic approach, the exclusion of non-empirical papers and the rating of methodological quality by two independent raters. Limitations were that we excluded studies published in languages other than English, that data extraction forms were developed for this study and hence not tested for validity, and that there was a potential publication bias in favour of significant findings. A better grasp of the psychological factors accounting for caregiver distress early in the course of illness may help us understand the trajectory of distress. This is an important step in preventing long-term distress in caregivers and

  11. A first step toward understanding best practices in leadership training in undergraduate medical education: a systematic review.

    Science.gov (United States)

    Webb, Allison M B; Tsipis, Nicholas E; McClellan, Taylor R; McNeil, Michael J; Xu, MengMeng; Doty, Joseph P; Taylor, Dean C

    2014-11-01

    To characterize leadership curricula in undergraduate medical education as a first step toward understanding best practices in leadership education. The authors systematically searched the PubMed, Education Resources Information Center, Academic Search Complete, and Education Full Text databases for peer-reviewed English-language articles published 1980-2014 describing curricula with interventions to teach medical students leadership skills. They characterized educational settings, curricular format, and learner and instructor types. They assessed effectiveness and quality of evidence using five-point scales adapted from Kirkpatrick's four-level training evaluation model (scale: 0-4) and a Best Evidence Medical Education guide (scale: 1-5), respectively. They classified leadership skills taught into the five Medical Leadership Competency Framework (MLCF) domains. Twenty articles describing 24 curricula met inclusion criteria. The majority of curricula (17; 71%) were longitudinal, delivered over periods of one semester to four years. The most common setting was the classroom (12; 50%). Curricula were frequently provided to both preclinical and clinical students (11; 46%); many (9; 28%) employed clinical faculty as instructors. The majority (19; 79%) addressed at least three MLCF domains; most common were working with others (21; 88%) and managing services (18; 75%). The median effectiveness score was 1.5, and the median quality of evidence score was 2. Most studies did not demonstrate changes in student behavior or quantifiable results. Aligning leadership curricula with competency models, such as the MLCF, would create opportunities to standardize evaluation of outcomes, leading to better measurement of student competency and a better understanding of best practices.

  12. Understanding Identity and Organizations

    DEFF Research Database (Denmark)

    Christensen, Lars Thøger

    2013-01-01

    The article reviews the book "Understanding Identity and Organizations," by Kate Kenny, Andrea Whitle, and Hugh Wilmott.......The article reviews the book "Understanding Identity and Organizations," by Kate Kenny, Andrea Whitle, and Hugh Wilmott....

  13. High temperature CO2 capture using calcium oxide sorbent in a fixed-bed reactor

    International Nuclear Information System (INIS)

    Dou Binlin; Song Yongchen; Liu Yingguang; Feng Cong

    2010-01-01

    The gas-solid reaction and breakthrough curve of CO 2 capture using calcium oxide sorbent at high temperature in a fixed-bed reactor are of great importance, and being influenced by a number of factors makes the characterization and prediction of these a difficult problem. In this study, the operating parameters on reaction between solid sorbent and CO 2 gas at high temperature were investigated. The results of the breakthrough curves showed that calcium oxide sorbent in the fixed-bed reactor was capable of reducing the CO 2 level to near zero level with the steam of 10 vol%, and the sorbent in CaO mixed with MgO of 40 wt% had extremely low capacity for CO 2 capture at 550 deg. C. Calcium oxide sorbent after reaction can be easily regenerated at 900 deg. C by pure N 2 flow. The experimental data were analyzed by shrinking core model, and the results showed reaction rates of both fresh and regeneration sorbents with CO 2 were controlled by a combination of the surface chemical reaction and diffusion of product layer.

  14. Qualification of the ALKASORB sorbent for the sorption-enhanced water-gas shift process

    Energy Technology Data Exchange (ETDEWEB)

    Van Selow, E.R.; Cobden, P.D.; Dijk, Van H.A.J.; Walspurger, S.; Verbraeken, P.A.; Jansen, D.

    2013-07-01

    For the sorption-enhanced water-gas shift (SEWGS) process, a new sorbent material has been qualified in a reactor of 2 m length under conditions close to industrial designs. The sorbent ALKASORB is a potassium-carbonate promoted hydrotalcite-based compound. ALKASORB is shown to have many favourable properties in comparison to the reference sorbent, in particular with respect to mechanical stability. The cyclic capacity of the new compound is substantially higher than the cyclic capacity of the reference sorbent, and it allows a reduction of the steam requirement of 50%. The sorbent has demonstrated catalytic activity for the water-gas shift reaction that is sufficient to omit a separate catalyst. It is demonstrated that the sorbent remains chemically and mechanically stable during operation of at least 2000 adsorption-desorption cycles, even in the presence of H2S in the feed. H2S is shown not to influence CO2 adsorption capacity and is co-captured with the CO2. In contrast to the reference material that showed mechanical degradation during extended adsorption-desorption cycles, the new material is stable and allows to obtain carbon capture levels exceeding 95% more efficiently and more economically since the required size of the vessels will be smaller.

  15. Simulation of mercury capture by sorbent injection using a simplified model.

    Science.gov (United States)

    Zhao, Bingtao; Zhang, Zhongxiao; Jin, Jing; Pan, Wei-Ping

    2009-10-30

    Mercury pollution by fossil fuel combustion or solid waste incineration is becoming the worldwide environmental concern. As an effective control technology, powdered sorbent injection (PSI) has been successfully used for mercury capture from flue gas with advantages of low cost and easy operation. In order to predict the mercury capture efficiency for PSI more conveniently, a simplified model, which is based on the theory of mass transfer, isothermal adsorption and mass balance, is developed in this paper. The comparisons between theoretical results of this model and experimental results by Meserole et al. [F.B. Meserole, R. Chang, T.R. Carrey, J. Machac, C.F.J. Richardson, Modeling mercury removal by sorbent injection, J. Air Waste Manage. Assoc. 49 (1999) 694-704] demonstrate that the simplified model is able to provide good predictive accuracy. Moreover, the effects of key parameters including the mass transfer coefficient, sorbent concentration, sorbent physical property and sorbent adsorption capacity on mercury adsorption efficiency are compared and evaluated. Finally, the sensitive analysis of impact factor indicates that the injected sorbent concentration plays most important role for mercury capture efficiency.

  16. Experimental evaluation of sorbents for sulfur control in a coal-fueled gas turbine slagging combustor

    International Nuclear Information System (INIS)

    Cowell, L.H.; Wen, C.S.; LeCren, R.T.

    1992-01-01

    This paper reports on a slagging combustor that has been used to evaluate three calcium-based sorbents for sulfur capture efficiency in order to assess their applicability for use in a oil-fueled gas turbine. Testing is competed in a bench-scale combustor with one-tenth the heat input needed for the full-scale gas turbine. The bench-scale rig is a two-stage combustor featuring a fuel-rich primary zone an a fuel-lean secondary zone. The combustor is operated at 6.5 bars with inlet air preheated to 600 K. Gas temperatures of 1840 K are generated in the primary zone and 1280 K in the secondary zone. Sorbents are either fed into the secondary zone or mixed with the coal-water mixture and fed into the primary zone. Dry powered sorbents are fed into the secondary zone by an auger into one of six secondary air inlet ports. The three sorbents tested in the secondary zone include dolomite, pressure-hydrated dolomitic lime, and hydrated lime. Sorbents have been tested while burning coal-water mixtures with coal sulfur loadings of 0.56 to 3.13 weight percent sulfur. Sorbents are injected into the secondary zone at varying flow rates such that the calcium/sulfur ratio varies from 0.5 to 10.0

  17. Reactivity improvement of Ca(OH)2 sorbent using diatomaceous earth (DE) from Aceh Province

    Science.gov (United States)

    Mariana, M.; Mahidin, M.; Mulana, F.; Agam, T.; Hafdiansyah, F.

    2018-04-01

    In this study, the diatomaceous earth (DE) from Aceh Province was used to increase the reactivity of Ca(OH)2sorbent. The high silica (SiO2) content of about 97% in the diatomaceous earth allows the increasing reactivity of Ca(OH)2sorbent by forming calcium silicate hydrate (CSH). The CSH improved the porosity characteristic of the sorbent. The improvement process was performed by mixing Ca(OH)2sorbent, diatomaceous earth and water in a beaker glass at the Ca(OH)2/DE weight ratio of 1:10 for 2 hand then dried at 120 °C for 24 h. The dried sorbent was calcined at 500 °C and 800 °C for 2 h. The activated sorbent was characterized using Scanning Electron Microscopy (SEM) for the morphological properties; X- Ray Diffraction (XRD) for the materials characteristics. The adsorption capacity of thesorbent was tested by methylene blue adsorption. The results showed that the Ca(OH)2/DEsorbent had a higher porosity than the Ca(OH)2 adsorbent.The results also showed that Ca(OH)2/DE which was calcined at higher temperature of 800 °C had a higher adsorption capacity compared to Ca(OH)2/DE which was calcined at lower temperature of 500 °C.

  18. Retrofit acid gas emission control for municipal waste incineration application of dry sorbent injection

    International Nuclear Information System (INIS)

    Zmuda, J.T.; Smith, P.V.

    1991-01-01

    Dry sorbent injection (DSI) has been successfully demonstrated on coal fired boiler applications as a means of reducing sulfur dioxide emissions. More recently, the dry sorbent injection process was applied to an existing municipal waste incinerator to provide acid gas emission controls. The results obtained from the successful demonstration of the sorbent injection system on an existing municipal incinerator are presented. Removal efficiencies of compounds such as HCl, SO 2 , SO 3 , mercury, and others by the use of sorbent injection are shown. Effects of the DSI system on downstream equipment, such as electrostatic precipitators, fabric filters, ash handling systems, and waste management is included. The impacts of the DSI system on the furnace is also discussed. In this paper a discussion of dry sorbent injection as a means of reducing acid gas and other emissions from existing municipal waste incinerators which may be affected by the regulations is presented. An application case study will outline typical exhaust conditions, expected pollution reductions, capital and operating costs, and type of available sorbents and their costs

  19. Activation and characterization of waste coffee grounds as bio-sorbent

    Science.gov (United States)

    Mariana; Marwan; Mulana, F.; Yunardi; Ismail, T. A.; Hafdiansyah, M. F.

    2018-03-01

    As the city well known for its culture of coffee drinkers, modern and traditional coffee shops are found everywhere in Banda Aceh, Indonesia. High number of coffee shops in the city generates large quantities of spent coffee grounds as waste without any effort to convert them as other valuable products. In an attempt to reduce environmental problems caused by used coffee grounds, this research was conducted to utilize waste coffee grounds as an activated carbon bio-sorbent. The specific purpose of this research is to improve the performance of coffee grounds bio-sorbent through chemical and physical activation, and to characterize the produced bio-sorbent. Following physical activation by carbonization, a chemical activation was achieved by soaking the carbonized waste coffee grounds in HCl solvent and carbonization process. The activated bio-sorbent was characterized for its morphological properties using Scanning Electron Microscopy (SEM), its functional groups by Fourier Transform Infra-Red Spectrophotometer (FTIR), and its material characteristics using X-Ray Diffraction (XRD). Characterization of the activated carbon prepared from waste coffee grounds shows that it meets standard quality requirement in accordance with Indonesian National Standard, SNI 06-3730-1995. Activation process has modified the functional groups of the waste coffee grounds. Comparing to natural waste coffee grounds, the resulted bio-sorbent demonstrated a more porous surface morphology following activation process. Consequently, such bio-sorbent is a potential source to be used as an adsorbent for various applications.

  20. Release of iodine radionuclides from gas media in a system of selective block sorbents

    International Nuclear Information System (INIS)

    Moskvin, L.N.; Miroshnikov, V.S.; Mel'nikov, V.A.; Chetverikov, V.V.

    1979-01-01

    A scheme of extracting iodine radionuclides from gas flows in a system of selective sorbents has been developed. The method provides separation of three forms of iodine: the aerosol component, the elementary iodine and organic-iodine compounds. Aerosols are trapped by a mechanical filter made of porous polytetrafluoroethylene with pores of no more than 1 μm. Silver-based sorbents for the elementary iodine are made by sintering the granular polytetrafluoroethylene (the size of granules is 0.1-0.5 mm) with of finely dispersed solver (5% mass). Organic iodine compounds are extracted by a silica sorbent impregnated with silver nitrate. The efficiency of sorbents was tested in gas flows with a known content of 131 I in the form of elementary iodine and methyl iodide. The results of experiments show that the efficiency of sorption of elementary iodine by a metallic-silver sorbent and of methyl iodide by a SiO 2 /AgNO 3 sorbent constitutes no less than 99% at a flow rate of up to 200 l/h. The iodine has been extracted at a flow rate of 100 l/h during 100 hours and for that time the efficiency of the iodine sorbtion has not changed. The suggested variant of extracting iodine radionuclides from gaseous media can be used both for fast control of iodine content in gas blowoffs and for researches aimed at studying the distribution of iodine forms in steam-and-gas media depending on nuclear plant operating conditions

  1. CaO-Based CO2 Sorbents Effectively Stabilized by Metal Oxides.

    Science.gov (United States)

    Naeem, Muhammad Awais; Armutlulu, Andac; Imtiaz, Qasim; Müller, Christoph R

    2017-11-17

    Calcium looping (i.e., CO 2 capture by CaO) is a promising second-generation CO 2 capture technology. CaO, derived from naturally occurring limestone, offers an inexpensive solution, but due to the harsh operating conditions of the process, limestone-derived sorbents undergo a rapid capacity decay induced by the sintering of CaCO 3 . Here, we report a Pechini method to synthesize cyclically stable, CaO-based CO 2 sorbents with a high CO 2 uptake capacity. The sorbents synthesized feature compositional homogeneity in combination with a nanostructured and highly porous morphology. The presence of a single (Al 2 O 3 or Y 2 O 3 ) or bimetal oxide (Al 2 O 3 -Y 2 O 3 ) provides cyclic stability, except for MgO which undergoes a significant increase in its particle size with the cycle number. We also demonstrate a direct relationship between the CO 2 uptake and the morphology of the synthesized sorbents. After 30 cycles of calcination and carbonation, the best performing sorbent, containing an equimolar mixture of Al 2 O 3 and Y 2 O 3 , exhibits a CO 2 uptake capacity of 8.7 mmol CO 2  g -1 sorbent, which is approximately 360 % higher than that of the reference limestone. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Understanding the motivations of health-care providers in performing female genital mutilation: an integrative review of the literature.

    Science.gov (United States)

    Doucet, Marie-Hélène; Pallitto, Christina; Groleau, Danielle

    2017-03-23

    Female genital mutilation (FGM) is a traditional harmful practice that can cause severe physical and psychological damages to girls and women. Increasingly, trained health-care providers carry out the practice at the request of families. It is important to understand the motivations of providers in order to reduce the medicalization of FGM. This integrative review identifies, appraises and summarizes qualitative and quantitative literature exploring the factors that are associated with the medicalization of FGM and/or re-infibulation. Literature searches were conducted in PubMed, CINAHL and grey literature databases. Hand searches of identified studies were also examined. The "CASP Qualitative Research Checklist" and the "STROBE Statement" were used to assess the methodological quality of the qualitative and quantitative studies respectively. A total of 354 articles were reviewed for inclusion. Fourteen (14) studies, conducted in countries where FGM is largely practiced as well as in countries hosting migrants from these regions, were included. The main findings about the motivations of health-care providers to practice FGM were: (1) the belief that performing FGM would be less harmful for girls or women than the procedure being performed by a traditional practitioner (the so-called "harm reduction" perspective); (2) the belief that the practice was justified for cultural reasons; (3) the financial gains of performing the procedure; (4) responding to requests of the community or feeling pressured by the community to perform FGM. The main reasons given by health-care providers for not performing FGM were that they (1) are concerned about the risks that FGM can cause for girls' and women's health; (2) are preoccupied by the legal sanctions that might result from performing FGM; and (3) consider FGM to be a "bad practice". The findings of this review can inform public health program planners, policy makers and researchers to adapt or create strategies to end

  3. Development of a Catalyst/Sorbent for Methane Reforming

    Energy Technology Data Exchange (ETDEWEB)

    B.H. Shans; T.D. Wheelock; Justinus Satrio; Karl Albrecht; Tanya Harris Janine Keeley; Ben Silva; Aaron Shell; Molly Lohry; Zachary Beversdorf

    2008-12-31

    This project led to the further development of a combined catalyst and sorbent for improving the process technology required for converting CH{sub 4} and/or CO into H{sub 2} while simultaneously separating the CO{sub 2} byproduct all in a single step. The new material is in the form of core-in-shell pellets such that each pellet consists of a CaO core surrounded by an alumina-based shell capable of supporting a Ni catalyst. The Ni is capable of catalyzing the reactions of steam with CH{sub 4} or CO to produce H{sub 2} and CO{sub 2}, whereas the CaO is capable of absorbing the CO{sub 2} as it is produced. The absorption of CO{sub 2} eliminates the reaction inhibiting effects of CO{sub 2} and provides a means for recovering the CO{sub 2} in a useful form. The present work showed that the lifecycle performance of the sorbent can be improved either by incorporating a specific amount of MgO in the material or by calcining CaO derived from limestone at 1100 C for an extended period. It also showed how to prepare a strong shell material with a large surface area required for supporting an active Ni catalyst. The method combines graded particles of {alpha}-alumina with noncrystalline alumina having a large specific surface area together with a strength promoting additive followed by controlled calcination. Two different additives produced good results: 3 {micro}m limestone and lanthanum nitrate which were converted to their respective oxides upon calcination. The oxides partially reacted with the alumina to form aluminates which probably accounted for the strength enhancing properties of the additives. The use of lanthanum made it possible to calcine the shell material at a lower temperature, which was less detrimental to the surface area, but still capable of producing a strong shell. Core-in-shell pellets made with the improved shell materials and impregnated with a Ni catalyst were used for steam reforming CH{sub 4} at different temperatures and pressures. Under all

  4. Some (But Not Much) Progress Toward Understanding Teenage Childbearing: A Review of Research From the Past Decade

    Science.gov (United States)

    Coyne, Claire A.; D’Onofrio, Brian M.

    2013-01-01

    In the decade and a half since Coley & Chase-Lansdale’s (1998) review of teenage childbearing there have been a number of studies investigating teenage childbearing from a developmental psychological perspective. Many of these studies have focused primarily on identifying individual, familial, and socioeconomic risk factors in childhood and adolescence that are highly correlated with teenage sexual behavior and teenage childbearing. We have an emerging understanding of teenage childbearing as the culmination of a complex cascade of experiences and decisions that overlap greatly with the risks for antisocial behavior. Much of this research, however, is limited by its reliance on correlational and cross-sectional research designs, which are not able to rigorously test causal inferences or to identify mechanisms associated with teenage childbearing. Innovative studies using large, nationally representative samples with quasi-experimental and longitudinal designs can expand on such descriptive studies. In particular, quasi-experimental studies can help answer questions about which risk factors are causally associated with teenage childbearing and suggest potential mechanisms that can explain how teenage childbearing is associated with poor outcomes. Future studies also will need to incorporate more precise measures of developmental processes and explore heterogeneity among adolescent mothers. Although advances have been made in the psychological study of teenage childbearing, more research is needed in order to answer important questions about which psychological processes are causally related to teenage childbearing and how teenage childbearing is associated with poor outcomes for young mothers and their offspring. PMID:22675905

  5. Understanding small biomolecule-biomaterial interactions: a review of fundamental theoretical and experimental approaches for biomolecule interactions with inorganic surfaces.

    Science.gov (United States)

    Costa, Dominique; Garrain, Pierre-Alain; Baaden, Marc

    2013-04-01

    Interactions between biomolecules and inorganic surfaces play an important role in natural environments and in industry, including a wide variety of conditions: marine environment, ship hulls (fouling), water treatment, heat exchange, membrane separation, soils, mineral particles at the earth's surface, hospitals (hygiene), art and buildings (degradation and biocorrosion), paper industry (fouling) and more. To better control the first steps leading to adsorption of a biomolecule on an inorganic surface, it is mandatory to understand the adsorption mechanisms of biomolecules of several sizes at the atomic scale, that is, the nature of the chemical interaction between the biomolecule and the surface and the resulting biomolecule conformations once adsorbed at the surface. This remains a challenging and unsolved problem. Here, we review the state of art in experimental and theoretical approaches. We focus on metallic biomaterial surfaces such as TiO(2) and stainless steel, mentioning some remarkable results on hydroxyapatite. Experimental techniques include atomic force microscopy, surface plasmon resonance, quartz crystal microbalance, X-ray photoelectron spectroscopy, fluorescence microscopy, polarization modulation infrared reflection absorption spectroscopy, sum frequency generation and time of flight secondary ion mass spectroscopy. Theoretical models range from detailed quantum mechanical representations to classical forcefield-based approaches. Copyright © 2012 Wiley Periodicals, Inc.

  6. How semantic deficits in schizotypy help understand language and thought disorders in schizophrenia: a systematic and integrative review

    Directory of Open Access Journals (Sweden)

    Hélio Anderson Tonelli

    2014-04-01

    Full Text Available Introduction: Disorders of thought are psychopathological phenomena commonly present in schizophrenia and seem to result from deficits of semantic processing. Schizotypal personality traits consist of tendencies to think and behave that are qualitatively similar to schizophrenia, with greater vulnerability to such disorder. This study reviewed the literature about semantic processing deficits in samples of individuals with schizotypal traits and discussed the impact of current knowledge upon the comprehension of schizophrenic thought disorders. Studies about the cognitive performance of healthy individuals with schizotypal traits help understand the semantic deficits underlying psychotic thought disorders with the advantage of avoiding confounding factors usually found in samples of individuals with schizophrenia, such as the use of antipsychotics and hospitalizations. Methods: A search for articles published in Portuguese or English within the last 10 years on the databases MEDLINE, Web of Science, PsycInfo, LILACS and Biological Abstracts was conducted, using the keywords semantic processing, schizotypy and schizotypal personality disorder. Results: The search retrieved 44 manuscripts, out of which 11 were firstly chosen. Seven manuscripts were additionally included after reading these papers. Conclusion: The great majority of the included studies showed that schizotypal subjects might exhibit semantic processing deficits. They help clarify about the interfaces between cognitive, neurophysiological and neurochemical mechanisms underlying not only thought disorders, but also healthy human mind's creativity.

  7. Understanding facial expressivity in autism spectrum disorder: An inside out review of the biological basis and clinical implications.

    Science.gov (United States)

    Deutsch, Stephen I; Raffaele, C Teal

    2018-05-16

    Deficits in decoding and understanding facially expressed emotions occur commonly in persons with autism spectrum disorder (ASD), which contribute to the impairment of social communication that serves as one of its core diagnostic criteria. Research suggests that abnormalities of visual scanning of the face, activation of key nodes within the "social brain" by facially expressed emotions, functional connectivity within and between nodes of the "social brain", and transduction of specific neurotransmitter/neuromodulatory signals contribute to the pathogenesis of these deficits in at least some persons with ASD. Importantly, the etiologies of these deficits are heterogeneous and include genetic, immunologic, and inflammatory mechanisms, as well as in utero exposures to drugs and toxins. The manifestation and severity of these deficits can also be influenced by developmental age, IQ and genetic background. Consistent with the goals of the Special Issue, the current Review is intended to familiarize the readership with several of the leading neurobiological mechanisms proposed to underlie these deficits in decoding facially expressed emotions and stimulate interest in translational preclinical and clinical investigations, whose ultimate purpose is to attenuate their severity and, thereby, improve functional outcomes of persons with ASD. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. Development of Novel Sorbents for Uranium Extraction from Seawater

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Wenbin [Univ. of Chicago, IL (United States); Taylor-Pashow, Kathryn [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-01-08

    As the uranium resource in terrestrial ores is limited, it is difficult to ensure a long-term sustainable nuclear energy technology. The oceans contain approximately 4.5 billion tons of uranium, which is one thousand times the amount of uranium in terrestrial ores. Development of technologies to recover the uranium from seawater would greatly improve the uranium resource availability, sustaining the fuel supply for nuclear energy. Several methods have been previously evaluated including solvent extraction, ion exchange, flotation, biomass collection, and adsorption; however, none have been found to be suitable for reasons such as cost effectiveness, long term stability, and selectivity. Recent research has focused on the amidoxime functional group as a promising candidate for uranium sorption. Polymer beads and fibers have been functionalized with amidoxime functional groups, and uranium adsorption capacities as high as 1.5 g U/kg adsorbent have recently been reported with these types of materials. As uranium concentration in seawater is only ~3 ppb, great improvements to uranium collection systems must be made in order to make uranium extraction from seawater economically feasible. This proposed research intends to develop transformative technologies for economic uranium extraction from seawater. The Lin group will design advanced porous supports by taking advantage of recent breakthroughs in nanoscience and nanotechnology and incorporate high densities of well-designed chelators into such nanoporous supports to allow selective and efficient binding of uranyl ions from seawater. Several classes of nanoporous materials, including mesoporous silica nanoparticles (MSNs), mesoporous carbon nanoparticles (MCNs), meta-organic frameworks (MOFs), and covalent-organic frameworks (COFs), will be synthesized. Selective uranium-binding liagnds such as amidoxime will be incorporated into the nanoporous materials to afford a new generation of sorbent materials that will be

  9. Development of Novel Sorbents for Uranium Extraction from Seawater

    International Nuclear Information System (INIS)

    Lin, Wenbin; Taylor-Pashow, Kathryn

    2014-01-01

    As the uranium resource in terrestrial ores is limited, it is difficult to ensure a long-term sustainable nuclear energy technology. The oceans contain approximately 4.5 billion tons of uranium, which is one thousand times the amount of uranium in terrestrial ores. Development of technologies to recover the uranium from seawater would greatly improve the uranium resource availability, sustaining the fuel supply for nuclear energy. Several methods have been previously evaluated including solvent extraction, ion exchange, flotation, biomass collection, and adsorption; however, none have been found to be suitable for reasons such as cost effectiveness, long term stability, and selectivity. Recent research has focused on the amidoxime functional group as a promising candidate for uranium sorption. Polymer beads and fibers have been functionalized with amidoxime functional groups, and uranium adsorption capacities as high as 1.5 g U/kg adsorbent have recently been reported with these types of materials. As uranium concentration in seawater is only ~3 ppb, great improvements to uranium collection systems must be made in order to make uranium extraction from seawater economically feasible. This proposed research intends to develop transformative technologies for economic uranium extraction from seawater. The Lin group will design advanced porous supports by taking advantage of recent breakthroughs in nanoscience and nanotechnology and incorporate high densities of well-designed chelators into such nanoporous supports to allow selective and efficient binding of uranyl ions from seawater. Several classes of nanoporous materials, including mesoporous silica nanoparticles (MSNs), mesoporous carbon nanoparticles (MCNs), meta-organic frameworks (MOFs), and covalent-organic frameworks (COFs), will be synthesized. Selective uranium-binding liagnds such as amidoxime will be incorporated into the nanoporous materials to afford a new generation of sorbent materials that will be

  10. Understanding Federalism.

    Science.gov (United States)

    Hickok, Eugene W., Jr.

    1990-01-01

    Urges returning to the original federalist debates to understand contemporary federalism. Reviews "The Federalist Papers," how federalism has evolved, and the centralization of the national government through acts of Congress and Supreme Court decisions. Recommends teaching about federalism as part of teaching about U.S. government…

  11. Evaluation of Carbon Dioxide Capture From Existing Coal Fired Plants by Hybrid Sorption Using Solid Sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Steven [Univ. of North Dakota, Grand Forks, ND (United States); Srinivasachar, Srivats [Envergex LLC, Sturbridge, MA (United States); Laudal, Daniel [Univ. of North Dakota, Grand Forks, ND (United States); Browers, Bruce [Barr Engineering, Minneapolis, MN (United States)

    2014-12-31

    A novel hybrid solid sorbent technology for CO₂ capture and separation from coal combustion-derived flue gas was evaluated. The technology – Capture of CO₂ by Hybrid Sorption (CACHYS™) – is a solid sorbent technology based on the following ideas: 1) reduction of energy for sorbent regeneration, 2) utilization of novel process chemistry, 3) contactor conditions that minimize sorbent-CO₂ heat of reaction and promote fast CO₂ capture, and 4) low-cost method of heat management. This report provides key information developed during the course of the project that includes sorbent performance, energy for sorbent regeneration, physical properties of the sorbent, the integration of process components, sizing of equipment, and overall capital and operational cost of the integrated CACHYS™ system. Seven sorbent formulations were prepared and evaluated at the lab-scale for energy requirements and CO₂ capture performance. Sorbent heat of regeneration ranged from 30-80 kJ/mol CO₂ and was found to be dependent on process conditions. Two sorbent formulations (designated HCK-4 & HCK-7) were down-selected for additional fixed-bed testing. Additional testing involved subjecting the sorbents to 100 continuous cycles in the fixed-bed reactor to determine performance as a function of time. The working capacity achieved for HCK-4 sorbent ranged from 5.5-8.0 g CO₂/100 g sorbent, while the HCK-7 typically ranged from 8.0-10.0 g CO₂/100 g sorbent. Overall, there was no deterioration in capacity with continuous cycling for either sorbent. The CACHYS™ bench-scale testing system designed and fabricated under this award consists of a dual circulating fluidized-bed adsorber and a moving-bed regenerator. The system takes a flue gas slipstream from the University of North Dakota’s coal-fired steam plant. Prior to being sent to the adsorber, the flue gas is scrubbed to remove SO₂ and particulate. During parametric testing of the adsorber, CO₂ capture achieved using

  12. Improved CO_2 adsorption capacity and cyclic stability of CaO sorbents incorporated with MgO

    International Nuclear Information System (INIS)

    Farah Diana Mohd Daud; Kumaravel Vignesh; Srimala Sreekantan; Abdul Rahman Mohamed

    2016-01-01

    Calcium oxide (CaO) sorbents incorporated with magnesium oxide (MgO) were synthesized using a co-precipitation route. The sorbents were prepared with different MgO concentrations (from 5 wt% to 30 wt%). The as-prepared sorbents were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX) and BET surface area analysis techniques. The sintering effect of CaO sorbents was decreased after the incorporation of MgO. The sorbents with 5 wt% and 10 wt% of MgO retained their CO_2 adsorption capacity over multiple cycles. Most importantly, CaO with 10 wt% MgO showed constant CO_2 adsorption capacity over 30 carbonation cycles. The results revealed that CaO with 10 wt% MgO is sufficient to produce sorbents with high surface area, good structural stability and enhanced CO_2 adsorption capacity. (authors)

  13. Efficient separations and processing crosscutting program: Develop and test sorbents

    International Nuclear Information System (INIS)

    Bray, L.A.

    1995-09-01

    This report summarizes work performed during FY 1995 under the task open-quotes Develop and Test Sorbents,close quotes the purpose of which is to develop high-capacity, selective solid extractants to recover cesium, strontium, and technetium from nuclear wastes. This work is being done for the Efficient Separations and Processing Crosscutting Program (ESP), operated by the U.S. Department of Energy's Office of Environmental Management's Office of Technology Development. The task is under the direction of staff at Pacific Northwest Laboratory (PNL) with key participation from industrial and university staff at 3M, St. Paul, Minnesota; IBC Advanced Technologies, Inc., American Forks, Utah; AlliedSignal, Inc., Des Plaines, Illinois, and Texas A ampersand M University, College Station, Texas. 3M and IBC are responsible for ligand and membrane technology development; AlliedSignal and Texas A ampersand M are developing sodium titanate powders; and PNL is testing the materials developed by the industry/university team members. Major accomplishments for FY 1995 are summarized in this report

  14. Water Utility Lime Sludge Reuse – An Environmental Sorbent ...

    Science.gov (United States)

    Lime sludge can be used as an environmental sorbent to remove sulfur dioxide (SO2) and acid gases, by the ultra-fine CaCO3 particles, and to sequester mercury and other heavy metals, by the Natural Organic Matter and residual activated carbon. The laboratory experimental set up included a simulated flue gas preparation unit, a lab-scale wet scrubber, and a mercury analyzer system. The influent mercury concentration was based on a range from 22 surveyed power plants. The reactivity of the lime sludge sample for acid neutralization was determined using a method similar to method ASTM C1318-95. Similar experiments were conducted using reagent calcium carbonate and calcium sulfate to obtain baseline data for comparing with the lime sludge test results. The project also evaluated the techno-economic feasibility and sustainable benefits of reusing lime softening sludge. If implemented on a large scale, this transformative approach for recycling waste materials from water treatment utilities at power generation utilities for environmental cleanup can save both water and power utilities millions of dollars. Huge amounts of lime sludge waste, generated from hundreds of water treatment utilities across the U.S., is currently disposed in landfills. This project evaluated a sustainable and economically-attractive approach to the use of lime sludge waste as a valuable resource for power generation utilities.

  15. Thermal and Chemical Stability of Crystalline Silicotitanate Sorbent

    International Nuclear Information System (INIS)

    Taylor, P.A.; Mattus, C.H.

    1999-01-01

    The Savannah River Site (SRS) is evaluating technologies for removing cesium-137 (137Cs) from the supemate solutions stored in the high-level waste tanks at the site. Crystalline silicotitanate sorbent (IONSIV IE-9 1 lo, UOP Molecular Sieves; Mount Laurel, NJ) is very effective for removing cesium from high-salt solution, such as the SRS supemates, and is currently being used at Oak Ridge National Laboratory to remove radioactive cesium from similar solutions, Because of the extremely high loading of 137Cs that would be expected for the large columns of crystalline silicotitanate (CST) that would be used for treating the SRS supemate, any loss of flow or cooling to the columns could result in high temperatures within the column from radiolytic heating. The ability of CST to retain previously loaded cesium while in contact with SRS tank supemates at various temperatures was determined by performing bench scale simulant tests using CST samples that were loaded with stable cesium and radi oactive cesium tracer. These results were compared with those obtained from loading tests at the same temperatures

  16. Method of making ionic liquid mediated sol-gel sorbents

    Science.gov (United States)

    Malik, Abdul; Shearrow, Anne M.

    2017-01-31

    Ionic liquid (IL)-mediated sol-gel hybrid organic-inorganic materials present enormous potential for effective use in analytical microextraction. One obstacle to materializing this prospect arises from high viscosity of ILs significantly slowing down sol-gel reactions. A method was developed which provides phosphonium-based, pyridinium-based, and imidazolium-based IL-mediated advanced sol-gel organic-inorganic hybrid materials for capillary microextraction. Scanning electron microscopy results demonstrate that ILs can serve as porogenic agents in sol-gel reactions. IL-mediated sol-gel coatings prepared with silanol-terminated polymers provided up to 28 times higher extractions compared to analogous sol-gel coatings prepared without any IL in the sol solution. This study shows that IL-generated porous morphology alone is not enough to provide effective extraction media: careful choice of the organic polymer and the precursor with close sol-gel reactivity must be made to ensure effective chemical bonding of the organic polymer to the created sol-gel material to be able to provide the desired sorbent characteristics.

  17. Please Wait, Processing: A Selective Literature Review of the Neurological Understanding of Emotional Processing in ASD and Its Potential Contribution to Neuroeducation

    OpenAIRE

    Shyman, Eric

    2017-01-01

    Autism spectrum disorder (ASD) and its corresponding conditions have been investigated from a multitude of perspectives resulting in varying understandings of its origin, its outplay, its prognosis, and potential methods of intervention and education for individuals with the disorder. One area that has contributed significantly to providing a different type of understanding is that of neuroscience, and specifically neuroimaging. This paper will offer a selective literature review of research ...

  18. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Volume 1, Bench-scale testing and analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  19. Removal of mercury from coal-combustion flue gas using regenerable sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Turchi, C S; Albiston, J; Broderick, T E; Stewart, R M

    1999-07-01

    The US EPA estimates that coal-fired power plants constitute the largest anthropogenic source of mercury emissions in the US. The Agency has contemplated emission regulations for power plants, but the large gas-flow rates and low mercury concentrations involved have made current treatment options prohibitively expensive. ADA Technologies, Inc. (Englewood, Colorado), in conjunction with the US DOE, is developing regenerable sorbents for the removal and recovery of mercury from flue gas. These sorbents are based on the ability of noble metals to amalgamate mercury at typical flue-gas temperatures and release mercury at higher temperatures. The process allows for recovery of mercury with minimal volumes of secondary wastes and no impact on fly ash quality. In 1997 and 1998, ADA tested a 20-cfm sorbent unit at CONSOL Inc.'s coal-combustion test facility in Library, PA. Results from the 1997 tests indicated that the sorbent can remove elemental and oxidized mercury and can be regenerated without loss of capacity. Design changes were implemented in 1998 to enhance the thermal efficiency of the process and to recover the mercury in a stable form. Testing during autumn, 1998 demonstrated 60% to 90% removal efficiency of mercury from a variety of different coals. However, contradictory removal results were obtained at the end of the test period. Subsequent laboratory analyses indicated that the sorbent had lost over half its capacity for mercury due to a decrease in available sites for mercury sorption. The presence of sulfur compounds on the sorbent suggests that thermal cycling may have condensed acid gases on the sorbent leading to deterioration of the active sorption sites. The regeneration time/temperature profile has been altered to minimize this potential in the upcoming power plant tests.

  20. CNTs reinforced super-hydrophobic-oleophilic electrospun polystyrene oil sorbent for enhanced sorption capacity and reusability

    KAUST Repository

    Wu, Jingya; Kyoungjin An, Alicia; Guo, Jiaxin; Lee, Eui-Jong; Usman Farid, Muhammad; Jeong, Sanghyun

    2016-01-01

    To meet the challenges of global oil spills and oil-water contamination, the development of a low-cost and reusable sorbents with good hydrophobicity and oleophilic nature is crucial. In this study, functionalized carbon nanotubes (CNTs) were wrapped in polystyrene (PS) polymer (PS-CNTs) and electrospun to create an effective and rigid sorbent for oil. Covalent modification and fluorination of CNTs improved their dispersibility and interfacial interaction with the polymer, resulting in a well-aligned CNTs configuration inside the porous fiber structure. Interestingly, the oil sorption process using PS-CNTs was observed to have two phases. First, the oil swiftly entered the membrane pores formed by interconnected nanofibers due to oleophilic properties of the micro-sized void. In the second phase, the oil not only moved to nano interior spaces of the fibers by capillary forces but also adsorbed on the surface of fibers where the latter was retained due to Van der Waals force. The sorption process fits well with the intra particle diffusion model. Maximum oil sorption capacity of the PS-CNTs sorbent for sunflower oil, peanut oil, and motor oils were 116, 123, and 112 g/g, respectively, which was 65% higher than that of the PS sorbent without CNTs. Overall, a significant increase in the porosity, surface area, water contact angle, and oleophilic nature was observed for the PS-CNTs composite sorbents. Not only did the PS-CNTs sorbents exhibited a promising oil sorption capacity but also showed potential for reusability, which is an important factor to be considered in determining the overall performance of the sorbent and its environmental impacts.

  1. CNTs reinforced super-hydrophobic-oleophilic electrospun polystyrene oil sorbent for enhanced sorption capacity and reusability

    KAUST Repository

    Wu, Jingya

    2016-12-05

    To meet the challenges of global oil spills and oil-water contamination, the development of a low-cost and reusable sorbents with good hydrophobicity and oleophilic nature is crucial. In this study, functionalized carbon nanotubes (CNTs) were wrapped in polystyrene (PS) polymer (PS-CNTs) and electrospun to create an effective and rigid sorbent for oil. Covalent modification and fluorination of CNTs improved their dispersibility and interfacial interaction with the polymer, resulting in a well-aligned CNTs configuration inside the porous fiber structure. Interestingly, the oil sorption process using PS-CNTs was observed to have two phases. First, the oil swiftly entered the membrane pores formed by interconnected nanofibers due to oleophilic properties of the micro-sized void. In the second phase, the oil not only moved to nano interior spaces of the fibers by capillary forces but also adsorbed on the surface of fibers where the latter was retained due to Van der Waals force. The sorption process fits well with the intra particle diffusion model. Maximum oil sorption capacity of the PS-CNTs sorbent for sunflower oil, peanut oil, and motor oils were 116, 123, and 112 g/g, respectively, which was 65% higher than that of the PS sorbent without CNTs. Overall, a significant increase in the porosity, surface area, water contact angle, and oleophilic nature was observed for the PS-CNTs composite sorbents. Not only did the PS-CNTs sorbents exhibited a promising oil sorption capacity but also showed potential for reusability, which is an important factor to be considered in determining the overall performance of the sorbent and its environmental impacts.

  2. Understanding Forest Health with Remote Sensing-Part II—A Review of Approaches and Data Models

    Directory of Open Access Journals (Sweden)

    Angela Lausch

    2017-02-01

    Full Text Available Stress in forest ecosystems (FES occurs as a result of land-use intensification, disturbances, resource limitations or unsustainable management, causing changes in forest health (FH at various scales from the local to the global scale. Reactions to such stress depend on the phylogeny of forest species or communities and the characteristics of their impacting drivers and processes. There are many approaches to monitor indicators of FH using in-situ forest inventory and experimental studies, but they are generally limited to sample points or small areas, as well as being time- and labour-intensive. Long-term monitoring based on forest inventories provides valuable information about changes and trends of FH. However, abrupt short-term changes cannot sufficiently be assessed through in-situ forest inventories as they usually have repetition periods of multiple years. Furthermore, numerous FH indicators monitored in in-situ surveys are based on expert judgement. Remote sensing (RS technologies offer means to monitor FH indicators in an effective, repetitive and comparative way. This paper reviews techniques that are currently used for monitoring, including close-range RS, airborne and satellite approaches. The implementation of optical, RADAR and LiDAR RS-techniques to assess spectral traits/spectral trait variations (ST/STV is described in detail. We found that ST/STV can be used to record indicators of FH based on RS. Therefore, the ST/STV approach provides a framework to develop a standardized monitoring concept for FH indicators using RS techniques that is applicable to future monitoring programs. It is only through linking in-situ and RS approaches that we will be able to improve our understanding of the relationship between stressors, and the associated spectral responses in order to develop robust FH indicators.

  3. Understanding the Connection Between Traumatic Brain Injury and Alzheimer’s Disease: A Population-Based Medical Record Review Analysis

    Science.gov (United States)

    2017-10-01

    Medical Record Review Analysis PRINCIPAL INVESTIGATOR: Allen W. Brown, MD CONTRACTING ORGANIZATION: Mayo Clinic Rochester, MN 55905 REPORT DATE...response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and... reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information

  4. Please Wait, Processing: A Selective Literature Review of the Neurological Understanding of Emotional Processing in ASD and Its Potential Contribution to Neuroeducation.

    Science.gov (United States)

    Shyman, Eric

    2017-11-17

    Autism spectrum disorder (ASD) and its corresponding conditions have been investigated from a multitude of perspectives resulting in varying understandings of its origin, its outplay, its prognosis, and potential methods of intervention and education for individuals with the disorder. One area that has contributed significantly to providing a different type of understanding is that of neuroscience, and specifically neuroimaging. This paper will offer a selective literature review of research that investigates the role of emotional processing in ASD, and how a deepening of this line of understanding can be used to inform more comprehensive educational practices.

  5. Please Wait, Processing: A Selective Literature Review of the Neurological Understanding of Emotional Processing in ASD and Its Potential Contribution to Neuroeducation

    Directory of Open Access Journals (Sweden)

    Eric Shyman

    2017-11-01

    Full Text Available Autism spectrum disorder (ASD and its corresponding conditions have been investigated from a multitude of perspectives resulting in varying understandings of its origin, its outplay, its prognosis, and potential methods of intervention and education for individuals with the disorder. One area that has contributed significantly to providing a different type of understanding is that of neuroscience, and specifically neuroimaging. This paper will offer a selective literature review of research that investigates the role of emotional processing in ASD, and how a deepening of this line of understanding can be used to inform more comprehensive educational practices.

  6. Teaching Teaching & Understanding Understanding

    DEFF Research Database (Denmark)

    2006-01-01

    "Teaching Teaching & Understanding Understanding" is a 19-minute award-winning short-film about teaching at university and higher-level educational institutions. It is based on the "Constructive Alignment" theory developed by Prof. John Biggs. The film delivers a foundation for understanding what...

  7. Carbon nanotubes applications in separation science: A review

    Energy Technology Data Exchange (ETDEWEB)

    Herrera-Herrera, Antonio V.; Gonzalez-Curbelo, Miguel Angel [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Quimica, Universidad de La Laguna (ULL), Avenida Astrofisico Francisco Sanchez s/n, 38206 La Laguna (Tenerife) (Spain); Hernandez-Borges, Javier, E-mail: jhborges@ull.es [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Quimica, Universidad de La Laguna (ULL), Avenida Astrofisico Francisco Sanchez s/n, 38206 La Laguna (Tenerife) (Spain); Rodriguez-Delgado, Miguel Angel [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Quimica, Universidad de La Laguna (ULL), Avenida Astrofisico Francisco Sanchez s/n, 38206 La Laguna (Tenerife) (Spain)

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer The use of CNTs in Separation Science in the period 2009-2011 is reviewed. Black-Right-Pointing-Pointer CNTs as stationary phases in LC, CE and GC. Black-Right-Pointing-Pointer CNTs as pseudostationary phases in EKC. Black-Right-Pointing-Pointer CNTs as sorbents in SPE and SPME. Black-Right-Pointing-Pointer Other uses of CNTs in separation science, as LDI substrates or in membranes. - Abstract: Due to the intensive and multidisciplinary research carried out during the last two decades on carbon nanotubes (CNTs), the scientific community understands nowadays much better the chemistry, structure and properties of these interesting materials. In fact, they have found their particular place in a wide number of application fields (nanotechnology, electronics, optics, medicine, etc.) among which Analytical Chemistry is becoming more and more important. The aim of this review is to provide an updated report of the most recent manuscripts (years 2009-2011) regarding the use of CNTs in Separation Science. In particular, the use of CNTs as solid-phase extraction and microextraction sorbents, as part of membranes as well as their use in chromatography and electrophoresis will be discussed and commented. Besides, although not as fully related to Separation Science as the previous techniques, the use of CNTs as laser desorption/ionization substrates has also been considered because of its importance in the field.

  8. Carbon nanotubes applications in separation science: A review

    International Nuclear Information System (INIS)

    Herrera-Herrera, Antonio V.; González-Curbelo, Miguel Ángel; Hernández-Borges, Javier; Rodríguez-Delgado, Miguel Ángel

    2012-01-01

    Highlights: ► The use of CNTs in Separation Science in the period 2009–2011 is reviewed. ► CNTs as stationary phases in LC, CE and GC. ► CNTs as pseudostationary phases in EKC. ► CNTs as sorbents in SPE and SPME. ► Other uses of CNTs in separation science, as LDI substrates or in membranes. - Abstract: Due to the intensive and multidisciplinary research carried out during the last two decades on carbon nanotubes (CNTs), the scientific community understands nowadays much better the chemistry, structure and properties of these interesting materials. In fact, they have found their particular place in a wide number of application fields (nanotechnology, electronics, optics, medicine, etc.) among which Analytical Chemistry is becoming more and more important. The aim of this review is to provide an updated report of the most recent manuscripts (years 2009–2011) regarding the use of CNTs in Separation Science. In particular, the use of CNTs as solid-phase extraction and microextraction sorbents, as part of membranes as well as their use in chromatography and electrophoresis will be discussed and commented. Besides, although not as fully related to Separation Science as the previous techniques, the use of CNTs as laser desorption/ionization substrates has also been considered because of its importance in the field.

  9. Predicting sorption of organic acids to a wide range of carbonized sorbents

    Science.gov (United States)

    Sigmund, Gabriel; Kah, Melanie; Sun, Huichao; Hofmann, Thilo

    2016-04-01

    Many contaminants and infochemicals are organic acids that undergo dissociation under environmental conditions. The sorption of dissociated anions to biochar and other carbonized sorbents is typically lower than that of neutral species. It is driven by complex processes that are not yet fully understood. It is known that predictive approaches developed for neutral compounds are unlikely to be suitable for organic acids, due to the effects of dissociation on sorption. Previous studies on the sorption of organic acids to soils have demonstrated that log Dow, which describes the decrease in hydrophobicity of acids upon dissociation, is a useful alternative to log Kow. The aim of the present study was to adapt a log Dow based approach to describe the sorption of organic acids to carbonized sorbents. Batch experiments were performed with a series of 9 sorbents (i.e., carbonized wood shavings, pig manure, and sewage sludge, carbon nanotubes and activated carbon), and four acids commonly used for pesticidal and biocidal purposes (i.e., 2,4-D, MCPA, 2,4-DB, and triclosan). Sorbents were comprehensively characterized, including by N2 and CO2 physisorption, Fourier transform infrared spectroscopy, and elemental analysis. The wide range of sorbents considered allows (i) discussing the mechanisms driving the sorption of neutral and anionic species to biochar, and (ii) their dependency on sorbate and sorbent properties. Results showed that the sorption of the four acids was influenced by factors that are usually not considered for neutral compounds (i.e., pH, ionic strength). Dissociation affected the sorption of the four compounds, and sorption of the anions ranged over five orders of magnitude, thus substantially contributing to sorption in some cases. For prediction purposes, most of the variation in sorption to carbonized sorbents (89%) could be well described with a two-parameter regression equation including log Dow and sorbent specific surface area. The proposed model

  10. Regenerable sorbents for mercury capture in simulated coal combustion flue gas.

    Science.gov (United States)

    Rodríguez-Pérez, Jorge; López-Antón, M Antonia; Díaz-Somoano, Mercedes; García, Roberto; Martínez-Tarazona, M Rosa

    2013-09-15

    This work demonstrates that regenerable sorbents containing nano-particles of gold dispersed on an activated carbon are efficient and long-life materials for capturing mercury species from coal combustion flue gases. These sorbents can be used in such a way that the high investment entailed in their preparation will be compensated for by the recovery of all valuable materials. The characteristics of the support and dispersion of gold in the carbon surface influence the efficiency and lifetime of the sorbents. The main factor that determines the retention of mercury and the regeneration of the sorbent is the presence of reactive gases that enhance mercury retention capacity. The capture of mercury is a consequence of two mechanisms: (i) the retention of elemental mercury by amalgamation with gold and (ii) the retention of oxidized mercury on the activated carbon support. These sorbents were specifically designed for retaining the mercury remaining in gas phase after the desulfurization units in coal power plants. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Immobilized humic substances and immobilized aggregates of humic substances as sorbent for solid phase extraction.

    Science.gov (United States)

    Erny, Guillaume L; Gonçalves, Bruna M; Esteves, Valdemar I

    2013-09-06

    In this work, humic substances (HS) immobilized, as a thin layer or as aggregates, on silica gel were tested as material for solid phase extraction. Some triazines (simazine, atrazine, therbutylazine, atrazine-desethyl-desisopropyl-2-hydroxy, ametryn and terbutryn), have been selected as test analytes due to their environmental importance and to span a large range of solubility and octanol/water partition coefficient (logP). The sorbent was obtained immobilizing a thin layer of HS via physisorption on a pre-coated silica gel with a cationic polymer (polybrene). While the sorbent could be used as it is, it was demonstrated that additional HS could be immobilized, via weak interactions, to form stable humic aggregates. However, while a higher quantity of HS could be immobilized, no significant differences were observed in the sorption parameters. This sorbent have been tested for solid phase extraction to concentrate triazines from aqueous matrixes. The sorbent demonstrated performances equivalent to commercial alternatives as a concentration factor between 50 and 200, depending on the type of triazines, was obtained. Moreover the low cost and the high flow rate of sample through the column allowed using high quantity of sorbent. The analytical procedure was tested with different matrixes including tap water, river water and estuarine water. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Hot coal gas desulfurization with manganese-based sorbents. Final report, September 1992--December 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hepworth, M.T.; Slimane, R.B.

    1994-11-01

    The focus of much current work being performed by the Morgantown Energy Technology Center (METC) of the Department of Energy on hot coal-derived fuel gas desulfurization is in the use of zinc-based sorbents. METC has shown interest in formulating and testing manganese-based pellets as alternative effective sulfur sorbents in the 700 to 1200{degree}C temperature range. To substantiate the potential superiority of Mn-based pellets, a systematic approach toward the evaluation of the desulfurizing power of single-metal sorbents is developed based on thermodynamic considerations. This novel procedure considered several metal-based sorbents and singled out manganese oxide as a prime candidate sorbent capable of being utilized under a wide temperature range, irrespective of the reducing power (determined by CO{sub 2}/CO ratio) of the fuel gas. Then, the thermodynamic feasibility of using Mn-based pellets for the removal of H{sub 2}S from hot-coal derived fuel gases, and the subsequent oxidative regeneration of loaded (sulfided) pellets was established. It was concluded that MnO is the stable form of manganese for virtually all commercially available coal-derived fuel gases. In addition, the objective of reducing the H{sub 2}S concentration below 150 ppMv to satisfy the integrated gasification combined cycle system requirement was shown to be thermodynamically feasible. A novel process is developed for the manufacture of Mn-based spherical pellets which have the desired physical and chemical characteristics required.

  13. Waste Derived Sorbents and Their Potential Roles in Heavy Metal Remediation Applications

    Directory of Open Access Journals (Sweden)

    Chiang Y. W.

    2013-04-01

    Full Text Available Inorganic waste materials that have the suitable inherent characteristics could be used as precursors for the synthesis of micro- and mesoporous materials, which present great potential to be re-utilized as sorbent materials for heavy metal remediation. Three inorganic waste materials were studied in the present work: water treatment residuals (WTRs from an integrated drinking water/wastewater treatment plant, and fly ash and bottom ash samples from a municipal solid waste incinerator (MSWI. These wastes were converted into three sorbent materials: ferrihydrite-like materials derived from drying of WTRs, hydroxyapatite-like material derived from ultrasound assisted synthesis of MSWI fly ash with phosphoric acid solution, and a zeolitic material derived from alkaline hydrothermal conversion of MSWI bottom ash. The performance of these materials, as well as their equivalent commercially available counterparts, was assessed for the adsorption of multiple heavy metals (As, Cd, Co, Ni, Pb, Zn from synthetic solutions, contaminated sediments and surface waters; and satisfactory results were obtained. In addition, it was observed that the combination of sorbents into sorbent mixtures enhanced the performance levels and, where applicable, stabilized inherently mobile contaminants from the waste derived sorbents.

  14. Evaluation of Dry Sorbent Injection Technology for Pre-Combustion CO{sub 2} Capture

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, Carl [URS Group, Inc., Austin, TX (United States); Steen, William [URS Group, Inc., Austin, TX (United States); Triana, Eugenio [URS Group, Inc., Austin, TX (United States); Machalek, Thomas [URS Group, Inc., Austin, TX (United States); Davila, Jenny [URS Group, Inc., Austin, TX (United States); Schmit, Claire [URS Group, Inc., Austin, TX (United States); Wang, Andrew [URS Group, Inc., Austin, TX (United States); Temple, Brian [URS Group, Inc., Austin, TX (United States); Lu, Yongqi [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Lu, Hong [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Zhang, Luzheng [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Ruhter, David [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Rostam-Abadi, Massoud [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Sayyah, Maryam [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Ito, Brandon [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Suslick, Kenneth [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States)

    2013-09-30

    This document summarizes the work performed on Cooperative Agreement DE-FE0000465, “Evaluation of Dry Sorbent Technology for Pre-Combustion CO{sub 2} Capture,” during the period of performance of January 1, 2010 through September 30, 2013. This project involves the development of a novel technology that combines a dry sorbent-based carbon capture process with the water-gas-shift reaction for separating CO{sub 2} from syngas. The project objectives were to model, develop, synthesize and screen sorbents for CO{sub 2} capture from gasified coal streams. The project was funded by the DOE National Energy Technology Laboratory with URS as the prime contractor. Illinois Clean Coal Institute and The University of Illinois Urbana-Champaign were project co-funders. The objectives of this project were to identify and evaluate sorbent materials and concepts that were suitable for capturing carbon dioxide (CO{sub 2}) from warm/hot water-gas-shift (WGS) systems under conditions that minimize energy penalties and provide continuous gas flow to advanced synthesis gas combustion and processing systems. Objectives included identifying and evaluating sorbents that efficiently capture CO{sub 2} from a gas stream containing CO{sub 2}, carbon monoxide (CO), and hydrogen (H{sub 2}) at temperatures as high as 650 °C and pressures of 400-600 psi. After capturing the CO{sub 2}, the sorbents would ideally be regenerated using steam, or other condensable purge vapors. Results from the adsorption and regeneration testing were used to determine an optimal design scheme for a sorbent enhanced water gas shift (SEWGS) process and evaluate the technical and economic viability of the dry sorbent approach for CO{sub 2} capture. Project work included computational modeling, which was performed to identify key sorbent properties for the SEWGS process. Thermodynamic modeling was used to identify optimal physical properties for sorbents and helped down-select from the universe of possible sorbent

  15. Performance of a novel synthetic Ca-based solid sorbent suitable for desulfurizing flue gases in a fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Pacciani, R.; Muller, C.R.; Davidson, J.F.; Dennis, J.S.; Hayhurst, A.N. [University of Cambridge, Cambridge (United Kingdom). Dept. of Chemical Engineering & Biotechnology

    2009-08-05

    The extent and mechanism of sulfation and carbonation of limestone, dolomite, and chalk, were compared with a novel, synthetic sorbent (85 wt % CaO and 15 wt % Ca{sub 12}A{sub l14}O{sub 33}), by means of experiments undertaken in a small, electrically heated fluidized bed. The sorbent particles were used either (I) untreated, sieved to two particle sizes and reacted with two different concentrations of SO{sub 2}, or (ii) after being cycled 20 times between carbonation, in 15 vol % CO{sub 2} in N2, and calcination, in pure N2, at 750 degrees C. The uptake of untreated limestone and dolomite was generally low (<0.2 g(SO{sub 2})/g(sorbent)), confirming previous results, However, the untreated chalk and the synthetic sorbent were found to be substantially more reactive with SO{sub 2}, and their final uptake was significantly higher (>0.5 g(SO{sub 2})/g(sorbent)) and essentially independent of the particle size. Here, comparisons are made on the basis of the sorbents in the calcined state. The capacities for the uptake of SO{sub 2}, on a basis of unit mass of calcined sorbent, were comparable for the chalk and the synthetic sorbent. However, previous work has demonstrated the ability of the synthetic sorbent to retain its capacity for CO{sub 2} over many cycles of carbonation and calcination: much more so than natural sorbents such as chalk and limestone. Accordingly, the advantage of the synthetic sorbent is that it could be used to remove CO{sub 2} from flue gases and, at the end of its life, to remove SO{sub 2} on a once-through basis.

  16. Silver-Loaded Aluminosilicate Aerogels As Iodine Sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Brian J. [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Kroll, Jared O. [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Peterson, Jacob A. [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Matyáš, Josef [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Olszta, Matthew J. [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Li, Xiaohong [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Vienna, John D. [Pacific Northwest National Laboratory, Richland, Washington 99354, United States

    2017-09-14

    This paper discusses the development of aluminosilicates aerogels as scaffolds for Ag0 nanoparticles used for chemisorption of I2(g). The starting materials for these scaffolds included both Na-Al-Si-O and Al-Si-O aerogels, both synthesized from metal alkoxides. The Ag0 particles are added by soaking the aerogels in AgNO3 followed by drying and flowing under H2/Ar to reduce Ag+ → Ag0. In some cases, samples were soaked in 3-(mercaptopropyl)trimethoxysilane under supercritical CO2 to add –SH tethers to the aerogel surfaces for more effective binding of Ag+. During the Ag+-impregnation steps, for the Na-Al-Si-O aerogels, Na was replaced with Ag, and for the Al-Si-O aerogel, Si was replaced with Ag. The Ag-loading of thiolated versus non-thiolated Na-Al-Si-O aerogels was comparable at ~35 at% whereas the Ag-loading in unthiolated Al-Si-O aerogels was significantly lower at ~ 7 at% after identical treatment. Iodine loadings in both thiolated and unthiolated Ag0-functionalized Na-Al-Si-O aerogels were > 0.5 g g-1 showing almost complete utilization of the Ag through chemisorption to form AgI. Iodine loading in the thiolated Al-Si-O aerogel was 0.31 g g-1. The control of Ag uptake over solution residence time and [AgNO3] demonstrates the ability to customize the Ag-loading in the base sorbent to regulate the capacity of iodine chemisorption. Consolidation experimental results are also presented.

  17. Understanding public attitudes to road-user safety – literature review: final report road safety research report no. 112.

    OpenAIRE

    Musselwhite, C.; Avineri, E.; Fulcher, E.; Goodwin, P.; Susilo, Y.

    2010-01-01

    Context and scope: \\ud – The literature reviewed in this report is primarily UK based and published post 2000. \\ud – In total, 72 articles have been reviewed in-depth and represent a mixture of qualitative, quantitative and mixed methodology primary research and a variety of reviews (see Appendix 2). \\ud – A wider definition of attitudes was incorporated to include a variety of psychosocial variables, such as social norms, risk, identity and impression management, pro-social behaviour, habit,...

  18. Helplessness: a systematic translational review of theory and evidence for its relevance to understanding and treating depression.

    Science.gov (United States)

    Pryce, Christopher R; Azzinnari, Damiano; Spinelli, Simona; Seifritz, Erich; Tegethoff, Marion; Meinlschmidt, Gunther

    2011-12-01

    Helplessness is a major concept in depression and a major theme in preclinical and clinical depression research. For example, in rodents and humans, the learned helplessness (LH) effect describes a specific deficit in behaviour to control aversive stimuli that is induced by prior exposure to uncontrollable aversive stimuli. The LH effect is objective and valid in that the cause of the behavioural deficit, namely uncontrollability, is clear; furthermore, the deficit induced is underlain by emotional, motivational and cognitive processes that are relevant to depression psychopathology. As a further example, helplessness, hopelessness, external locus of control and causal attribution are inter-related and major themes in psychological theories (primarily cognitive theories) of depression. Despite this broad interest in helplessness, it can be argued that its potential usefulness as a scientific and clinical concept has so far not been investigated optimally, including with respect to its application in research aimed at development of improved anti-depressant pharmacotherapy. The first aim of this review was to describe and integrate the psychological evidence and the neurobiological evidence for the LH effect in rodents and healthy humans and for helplessness in depressed patients. The second aim was to conduct three systematic reviews, namely of rodent studies of the LH effect, rodent studies of effects of psychopharmacological agents on the LH effect, and human studies of efficacy of pharmacotherapeutic and psychotherapeutic treatment on helplessness in depressed patients. With respect to the first aim, the major findings are: the specificity of the LH effect in otherwise non-manipulated rodents and healthy humans has been under-estimated, and the LH effect is a specific learned aversive uncontrollability (LAU) effect. There is theoretical and empirical support for a model in which a specific LAU effect induced by a life event of major emotional significance can

  19. Understanding performance limitation and suppression of leakage current or self-discharge in electrochemical capacitors: a review.

    Science.gov (United States)

    Ike, Innocent S; Sigalas, Iakovos; Iyuke, Sunny

    2016-01-14

    Self-discharge is known to have considerable adverse effects on the performance and application of electrochemical capacitors (ECs). Thus, obtaining an understanding of EC self-discharge mechanism(s) and subsequent derivation and solution of EC models, subject to a particular mechanism or combination of mechanisms during charging, discharging and storage of the device, is the only way to solve problems associated with EC self-discharge. In this review, we summarize recent progress with respect to EC self-discharge by considering the two basic types, electric double-layer capacitors (EDLC) and pseudocapacitors, and their hybrids with their respective charge storage mechanisms, distinguishable self-discharge mechanisms, charge redistribution and charge/energy loss during self-discharge. It was clearly observed that most of the voltage reduction is not purely due to the self-discharge effect but is basically due to redistribution of charge carriers deep inside pores and can therefore be retrieved from a capacitor during long-time discharging. Tuning the self-discharge rate is therefore feasible for single-walled carbon nanotube (SWNT) ECs and can be achieved by simply adjusting the surface chemistry of the nanotubes. The effects of surface chemistry modification on EC self-discharge are very important in studying and suppressing the self-discharge process and will benefit potential applications of ECs with respect to energy retention. Self-discharge can be averted by the use of redox couples that are transformed to insoluble species via electrolysis and adsorbed onto the activated carbon electrode in redox-couple EDLCs, thus transforming the EDLC electrolyte into a material that can store charge. Self-discharge in ECs can also be successfully suppressed by utilizing an ion-interchange layer (ion-exchange membrane), separator or CuSO4 mobile electrolyte that can be converted into an insoluble species by electrolysis during the charge/discharge process. This will help

  20. What Is Our Current Understanding of One-to-One Computer Projects: A Systematic Narrative Research Review

    Science.gov (United States)

    Fleischer, Hakan

    2012-01-01

    The aim of this article is to review cross-disciplinary accumulated empirical research on one-to-one computer projects in school settings as published in peer-reviewed journals between 2005 and 2010, particularly the results of teacher- and pupil-oriented studies. Six hundred and five research articles were screened at the abstract and title…

  1. Aerosol Formation during the Combustion of Straw with Addition of Sorbents

    DEFF Research Database (Denmark)

    Zeuthen, Frederik Jacob; Jensen, Peter Arendt; Jensen, Jørgen P.

    2007-01-01

    , calcium phosphate, Bentonite, ICA5000, and clay. The addition of chalk increased the aerosol mass concentration by 24%. Experiments in a laminar flow aerosol condenser with the six sorbents were carried out in the laboratory using a synthetic flue gas to avoid fluctuations in the alkali feeding......The influence of six sorbents on aerosol formation during the combustion of straw in a 100 MW boiler on a Danish power plant has been studied in full-scale. The following sorbents were studied: ammonium sulfate, monocalcium phosphate, Bentonite, ICA5000, clay, and chalk. Bentonite and ICA5000...... are mixtures of clay minerals and consist mainly of the oxides from Fe, Al, and Si. The straw used was Danish wheat and seed grass. Measurements were also made with increased flow of primary air. The experiments showed between 46% and 70% reduction in particle mass concentrations when adding ammonium sulfate...

  2. Adsorption of Polycyclic Aromatic Hydrocarbons (PAHS from Aqueous Solutions on Different Sorbents

    Directory of Open Access Journals (Sweden)

    Smol Marzena

    2014-12-01

    Full Text Available This paper presents the results of the possibility and effectiveness of PAHs removal from a model aqueous solution, during the sorption on the selected sorbents. Six PAHs (naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene listed by EPA for the analysis in the environmental samples were determined. Model aqueous solution was prepared with RESTEK 610 mix PAHs standard. After the sorption process, decrease in the concentration of individual hydrocarbons was observed. The removal percentage was dependent on the type of sorbent (quartz sand, mineral sorbent, activated carbon. The highest efficiency (98.1% was observed for activated carbon.. The results shows that the sorption processes can be used in aqueous solutions treatment procedures.

  3. DEVELOPMENT OF DISPOSABLE SORBENTS FOR CHLORIDE REMOVAL FROM HIGH TEMPERATURE COAL-DERIVED GASES

    Energy Technology Data Exchange (ETDEWEB)

    Gopala Krishnan; Raghubir Gupta

    1999-09-01

    Advanced integrated-gasification combined-cycle (IGCC) and integrated-gasification fuel cell (IGFC) systems require the development of high temperature sorbents for the removal of hydrogen chloride (HCl) vapor to less than 1 parts-per-million (ppm) levels. HCl is a highly reactive, corrosive, and toxic gas which must be removed to meet environmental regulations, to protect power generation equipment, and to minimize deterioration of hot gas desulfurization sorbents. The objective of this program was to develop disposable, alkali-based sorbents capable of reducing HCl vapor levels to less than 1 ppm in the temperature range from 400 to 750 C and pressures in the range from 1 to 20 atm. The primary areas of focus of this program were to investigate different methods of sorbent fabrication, testing their suitability for different reactor configurations, obtaining reaction kinetics data, and conducting a preliminary economic feasibility assessment. This program was a joint effort between SRI International (SRI), Research Triangle Institute (RTI), and General Electric Corporate Research and Development (GE-CRD). SRI, the prime contractor and RTI, a major subcontractor, performed most of the work in this program. Thermochemical calculations indicated that sodium-based sorbents were capable of reducing HCl vapor levels to less than 1 ppm at temperatures up to 650 C, but the regeneration of spent sorbents would require complex process steps. Nahcolite (NaHCO{sub 3}), a naturally-occurring mineral, could be used as an inexpensive sorbent to remove HCl vapor in hot coal gas streams. In the current program, nahcolite powder was used to fabricate pellets suitable for fixed-bed reactors and granules suitable for fluidized-bed reactors. Pilot-scale equipment were used to prepare sorbents in large batches: pellets by disk pelletization and extrusion techniques, and granules by granulation and spray-drying techniques. Bench-scale fixed- and fluidized-bed reactors were assembled at

  4. Ionic liquid-functionalized mesoporous sorbents and their use in the capture of polluting gases

    Science.gov (United States)

    Lee, Jong Suk; Koros, William J.; Bhuwania, Nitesh; Hillesheim, Patrick C.; Dai, Sheng

    2016-01-12

    A composite structure for capturing a gaseous electrophilic species, the composite structure comprising mesoporous refractory sorbent particles on which an ionic liquid is covalently attached, wherein said ionic liquid includes an accessible functional group that is capable of binding to said gaseous electrophilic species. In particular embodiments, the mesoporous sorbent particles are contained within refractory hollow fibers. Also described is a method for capturing a gaseous electrophilic species by use of the above-described composite structure, wherein the gaseous electrophilic species is contacted with the composite structure. In particular embodiments thereof, cooling water is passed through the refractory hollow fibers containing the IL-functionalized sorbent particles in order to facilitate capture of the gaseous electrophilic species, and then steam is passed through the refractory hollow fibers to facilitate release of the gaseous electrophilic species such that the composite structure can be re-used to capture additional gas.

  5. Removal of dissolved textile dyes from wastewater by a compost sorbent

    Science.gov (United States)

    Tsui, L.S.; Roy, W.R.; Cole, M.A.

    2003-01-01

    The objective of this study was to evaluate the potential for treating dye-contaminated waste streams by sorption using compost as a low-cost sorbent. A mature, thermophilic compost sample was used to sorb CI Acid Black 24, CI Acid Orange 74, CI Basic Blue 9, CI Basic Green 4, CI Direct Blue 71, CI Direct Orange 39, CI Reactive Orange 16 and CI Reactive Red 2 from solution using a batch-sorption method. With the exception of the two reactive dyes, the sorption kinetics were favourable for a continuous-flow treatment process with the compost-dye mixtures reaching a steady state within 3-5 h. Based on limited comparisons, the affinity of the compost for each dye appeared to be competitive with other non-activated carbon sorbents. The results suggest that additional research on using compost as a sorbent for dye-contaminated solutions is warranted.

  6. Assessment of raw luffa as a natural hollow oleophilic fibrous sorbent for oil spill cleanup

    Directory of Open Access Journals (Sweden)

    Ola Abdelwahab

    2014-03-01

    Full Text Available Oil spills have a global concern due to its environmental and economical impact. Various commercial systems have been developed to control these spills, including the use of fibers as sorbents. However, plant biomass is renewable resource that can be converted into useful materials and energy. Luffa, an agricultural waste, was used as a sorbent material. The present study examines the adsorption capacity of raw luffa fibers for different types of oil and water pickup. The investigation revealed that the efficiency of fibers to remove crude oil from sea water was related to the surface properties of the fibers, concentration of the oil, amount of the fibers, as well as the temperature of the crude oil. The results show high sorption efficiency of luffa fibers for different kinds of oil. This sorbent also exhibited a good reusability since the decrease in sorption efficiency did not exceed 50% of the initial value after three sorption cycles.

  7. Adsorption of Carbon Dioxide, Ammonia, Formaldehyde, and Water Vapor on Regenerable Carbon Sorbents

    Science.gov (United States)

    Wojtowicz, Marek A.; Cosgrove, Joseph E.; Serio, Michael A.; Wilburn, Monique

    2015-01-01

    Results are presented on the development of reversible sorbents for the combined carbon dioxide, moisture, and trace-contaminant (TC) removal for use in Extravehicular Activities (EVAs), and more specifically in the Primary Life Support System (PLSS). The currently available life support systems use separate units for carbon dioxide, trace contaminants, and moisture control, and the long-term objective is to replace the above three modules with a single one. Furthermore, the current TC-control technology involves the use of a packed bed of acid-impregnated granular charcoal, which is nonregenerable, and the carbon-based sorbent under development in this project can be regenerated by exposure to vacuum at room temperature. In this study, several carbon sorbents were fabricated and tested for simultaneous carbon dioxide, ammonia, formaldehyde, and water sorption. Multiple adsorption/vacuum-regeneration cycles were demonstrated at room temperature, and also the enhancement of formaldehyde sorption by the presence of ammonia in the gas mixture.

  8. Efficiency of sugarcane bagasse-based sorbents for oil removal from engine washing wastewater.

    Science.gov (United States)

    Guilharduci, Viviane Vasques da Silva; Martelli, Patrícia Benedini; Gorgulho, Honória de Fátima

    2017-01-01

    This work evaluates the efficiency of sugarcane bagasse-based sorbents in the sorption of oil from engine washing wastewater. The sorbents were obtained from sugarcane bagasse in the natural form (SB-N) and modified with either acetic anhydride (SB-Acet) or 3-aminopropyltriethoxysilane (SB-APTS). The results showed that the sorption capacity of these materials decreased in the following order: SB-APTS > SB-N > SB-Acet. The superior oil sorption capacity observed for SB-APTS was attributed to the polar amino end groups in the silane structure, which acted to increase the hydrophilic character of the fibers. However, all the sorbents obtained in this study were able to clean a real sample of wastewater from engine washing, leading to significant reductions in suspended matter, sediment, anionic surfactants, and turbidity.

  9. Cadmium adsorption by coal combustion ashes-based sorbents-Relationship between sorbent properties and adsorption capacity

    Energy Technology Data Exchange (ETDEWEB)

    Balsamo, Marco; Di Natale, Francesco; Erto, Alessandro; Lancia, Amedeo [Dipartimento di Ingegneria Chimica, Universita degli Studi di Napoli Federico II, Piazzale Vincenzo Tecchio 80, 80125 Napoli (Italy); Montagnaro, Fabio, E-mail: fabio.montagnaro@unina.it [Dipartimento di Chimica, Universita degli Studi di Napoli Federico II, Complesso Universitario di Monte Sant' Angelo, 80126 Napoli (Italy); Santoro, Luciano [Dipartimento di Chimica, Universita degli Studi di Napoli Federico II, Complesso Universitario di Monte Sant' Angelo, 80126 Napoli (Italy)

    2011-03-15

    A very interesting possibility of coal combustion ashes reutilization is their use as adsorbent materials, that can also take advantage from proper beneficiation techniques. In this work, adsorption of cadmium from aqueous solutions was taken into consideration, with the emphasis on the intertwining among waste properties, beneficiation treatments, properties of the beneficiated materials and adsorption capacity. The characterization of three solid materials used as cadmium sorbents (as-received ash, ash sieved through a 25 {mu}m-size sieve and demineralized ash) was carried out by chemical analysis, infrared spectroscopy, laser granulometry and mercury porosimetry. Cadmium adsorption thermodynamic and kinetic tests were conducted at room temperature, and test solutions were analyzed by atomic absorption spectrophotometry. Maximum specific adsorption capacities resulted in the range 0.5-4.3 mg g{sup -1}. Different existing models were critically considered to find out an interpretation of the controlling mechanism for adsorption kinetics. In particular, it was observed that for lower surface coverage the adsorption rate is governed by a linear driving force while, once surface coverage becomes significant, mechanisms such as the intraparticle micropore diffusion may come into play. Moreover, it was shown that both external fluid-to-particle mass transfer and macropore diffusion hardly affect the adsorption process, which was instead regulated by intraparticle micropore diffusion: characteristic times for this process ranged from 4.1 to 6.1 d, and were fully consistent with the experimentally observed equilibrium times. Results were discussed in terms of the relationship among properties of beneficiated materials and cadmium adsorption capacity. Results shed light on interesting correlations among solid properties, cadmium capture rate and maximum cadmium uptake.

  10. Carbon nanocomposite sorbent and methods of using the same for separation of one or more materials from a gas stream

    Science.gov (United States)

    Olson, Edwin S.; Pavlish, John Henry

    2017-05-30

    The present invention relates to carbon nanocomposite sorbents. The present invention provides carbon nanocomposite sorbents, methods for making the same, and methods for separation of a pollutant from a gas that includes that pollutant. Various embodiments provide a method for reducing the mercury content of a mercury-containing gas.

  11. LOW CONCENTRATION MERCURY SORPTION MECHANISMS AND CONTROL BY CALCIUM-BASED SORBENTS; APPLICATION IN COAL-FIRED PROCESSES

    Science.gov (United States)

    The capture of elemental mercury (Hgo) and mercuric chloride (HgCl2) by three types of calcium (Ca)-based sorbents was examined in this bench-scale study under conditions prevalent in coal fired utilities. Ca-based sorbent performances were compared to that of an activated carbon...

  12. The Relative Influence of Turbulence and Turbulent Mixing on the Adsorption of Mercury within a Gas-Sorbent Suspension

    Science.gov (United States)

    Our previous investigations demonstrated that entrained flow or in-flight adsorption can be a more effective and flexible approach to trace gas adsorption than fixed sorbent beds. The present investigation establishes the turbulent mixing that accompanies sorbent injection is an ...

  13. INFLUENCE OF SOLVENT AND SORBENT CHARACTERISTICS ON DISTRIBUTION OF PENTACHLOROPHENOL IN OCTANOL-WATER AND SOIL-WATER SYSTEMS

    Science.gov (United States)

    Sorbent and solvent characteristics influencing sorption of pentachlorophenol (PCP) were investigated. Analysis of aqueous sorption data for several sorbents over a broad pH range suggested hydrophobic sorption of neutral PCP predominates at pH 7. At pH > 7, sorption of the penta...

  14. Experimental investigation of adsorption of NO and SO2 on modified activated carbon sorbent from flue gases

    International Nuclear Information System (INIS)

    Zhu, J.L.; Wang, Y.H.; Zhang, J.C.; Ma, R.Y.

    2005-01-01

    It is indicated that modified carbon is a practical sorbent for removal of NO and SO 2 from waste gases by the adsorption method. The ideal compositions for the prepared sorbent were 4.0 wt.% and 2.5 wt.% Na 2 CO 3 and KOH at the experimental conditions, respectively, shortened as ACNaK 2.5 . Experimental investigation showed that the sorbent had a comparatively high breakthrough adsorption capacity of NO and SO 2 , about 5.8 g (NO + SO 2 )/100 g sorbent. It is indicated that a relatively high adsorption temperature would benefit the sorbent adsorption capacities on NO and SO 2 at a certain space velocity and pressure. Further study revealed that the ACNaK 2.5 sorbent had good regenerability at the experimental conditions, which implied that the ACNaK 2.5 sorbent would be a useful sorbent for simultaneous removal of NO and SO 2 from waste gases by adsorption

  15. Multifunctional humate-based magnetic sorbent: Preparation, properties and sorption of Cu (II), phosphates and selected pesticides

    Czech Academy of Sciences Publication Activity Database

    Janoš, P.; Kormunda, M.; Novák, František; Životský, O.; Fuitová, J.; Pilařová, V.

    2013-01-01

    Roč. 73, č. 1 (2013), s. 46-52 ISSN 1381-5148 Grant - others:GA ČR(CZ) GAP106/12/1116 Program:GA Institutional support: RVO:60077344 Keywords : magnetic sorbent * humate-based sorbent * heavy metals * phosphate * pesticides Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.822, year: 2013

  16. TG-FTIR measurement of CO2-H2O co-adsorption for CO2 air capture sorbent screening

    NARCIS (Netherlands)

    Smal, I.M.; Yu, Qian; Veneman, Rens; Fränzel-Luiten, B.; Brilman, Derk Willem Frederik

    2014-01-01

    Capturing atmospheric CO2 using solid sorbents is gaining interest. As ambient air normally contains much more (up to 100 times) water than CO2, a selective sorbent is desirable as co-adsorption will most likely occur. In this study, a convenient method based on an TG-FTIR analysis system is

  17. Technology assessment guide for application of engineered sorbent barriers to low-level radioactive waste disposal sites

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H.D.; Jones, E.O.; Depner, J.P.

    1989-06-01

    An engineered sorbent barrier (ESB) uses sorbent materials (such as activated carbon or natural zeolites) to restrict migration of radionuclides from low-level waste sites. The permeability of the ESB allows moisture to pass while the sorbent material traps or absorbs contaminants. In contrast, waste sites with impermeable barriers could fill with water, especially those waste sites in humid climates. A sorbent barrier can be a simple, effective, and inexpensive method for restricting radionuclide migration. This report provides information and references to be used in assessing the sorbent barrier technology for low-level waste disposal. The ESB assessment is based on sorbent material and soil properties, site conditions, and waste properties and inventories. These data are used to estimate the thickness of the barrier needed to meet all performance requirements for the waste site. This document addresses the following areas: (1) site information required to assess the need and overall performance of a sorbent barrier; (2) selection and testing of sorbent materials and underlying soils; (3) use of radionuclide transport models to estimate the required barrier thickness and long-term performance under a variety of site conditions; (4) general considerations for construction and quality assurance; and (5) cost estimates for applying the barrier. 37 refs., 6 figs., 2 tabs.

  18. Phosphate Adsorption using Modified Iron Oxide-based Sorbents in Lake Water: Kinetics, Equilibrium, and Column Tests

    Science.gov (United States)

    Adsorption behavior of Bayoxide ® E33 (E33) and three E33-modified sorbents for the removal of phosphate from lake water was investigated in this study. E33-modified sorbents were synthesized by coating with manganese (E33/Mn) and silver (E33/AgI and E33/AgII) nanoparticles. Adso...

  19. The study of sorption of cesium radionuclides by 'T-55' ferrocyanide sorbent from various types of liquid radioactive wastes

    International Nuclear Information System (INIS)

    Semenischev, V.S.; Voronina, A.V.; Bykov, A.A.

    2013-01-01

    The sorption of caesium by T-55 sorbent from different types of liquid radioactive wastes is studied. It is shown that the sorbent can be used for extraction of cesium from high level acidic and saline solutions and also for decontamination of caesium contaminated waters containing surfactants and EDTA. (author)

  20. Calcium looping technology using improved stability nanostructured sorbent for cyclic CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Cong; Zheng, Ying; Ding, Ning; Zheng, Chu-guang [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion

    2013-07-01

    One of the post-combustion CO{sub 2} capture technologies that have sufficiently been proved to be the best candidates for practical large scale post-combustion application is the calcium looping cycle. However, the CO{sub 2} capture capacity of a calcium-based sorbent derived from natural limestone decays through long-term cyclic utilization; thus, the development of novel sorbents to achieve a high CO{sub 2} capture capacity is an critical challenge for the calcium looping cycle technology. In this paper, we report the preparation and character of a new calcium-based sorbent produced via the combustion of a dry gel. The results show that the novel calcium-based sorbent has a much higher residual carbonation conversion as well as a better performance of anti-sintering when compared with the calcium-based sorbent derived from commercial micrometer grade CaCO{sub 3} and nanometer grade CaCO{sub 3}. It is reasonable to propose that the different final carbonation performances are induced by their different pore structures and BET surface areas rather than by different particle sizes. Compared with the commercial nano CaO, the morphology of the new sorbent shows a more rough porous appearance with hollow nanostructure. During carbonation, CO{sub 2} diffused more easily through the hollow structure than through a solid structure to reach the unreacted CaO. Besides, there is less chance for the hollow nanostructured particles to be merged together during the high temperature reactions.

  1. The use of lightweight expanded clay aggregate (LECA) as sorbent for PAHs removal from water

    International Nuclear Information System (INIS)

    Nkansah, Marian Asantewah; Christy, Alfred A.; Barth, Tanja; Francis, George William

    2012-01-01

    Highlights: ► Effect of contact time on sorption PAH by LECA. ► Effect of mass of sorbent (LECA) on sorption of PAH. ► Sorption Isotherms for PAH-LECA interaction. - Abstract: Lightweight expanded clay aggregate (LECA) has been explored as a sorbent for the removal of PAHs (phenanthrene, fluoranthene and pyrene) from water. The efficacy of LECA as a sorbent for PAHs was assessed using contact time, mass of sorbent and sorption isotherms in a series of batch experiments. Maximum (optimum) sorption was reached at 21 h after which the amount of PAHs sorbed remained almost constant. Batch experiments were conducted by shaking a 100 ml solution mixture of individual PAHs (containing 0.02 mg/L) with LECA. The maximum sorption was 70.70, 70.82 and 72.12%, respectively for phenanthrene, fluoranthene and pyrene when a mass of 0.2 g of sorbent was used. There was an increase in sorption as a result of an increase in mass of sorbent until a maximum was reached at a mass of 4.0 g LECA with 92.61, 93.91 and 94.15% sorption of phenanthrene, fluoranthene and pyrene respectively. Sorption data were fitted to the linearised forms of the Freundlich and Langmuir isotherm models to determine the water-LECA partitioning coefficient. Physical sorption caused by the aromatic nature of the compounds was the main mechanism that governed the removal process while the hydrophobicity of the PAHs also influenced the sorption capacity. LECA can be used as an alternative method for aqueous PAHs removal.

  2. A decontamination system for chemical weapons agents using a liquid solution on a solid sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Waysbort, Daniel [Israel Institute for Biological Research, PO Box 19, Ness-Ziona 74100 (Israel); McGarvey, David J. [R and T Directorate, Edgewood Chemical and Biological Center (ECBC), Aberdeen Proving Ground-Edgewood Area, MD 21010 (United States)], E-mail: david.mcgarvey@us.army.mil; Creasy, William R.; Morrissey, Kevin M.; Hendrickson, David M. [SAIC, P.O. Box 68, Gunpowder Branch, Aberdeen Proving Ground, MD 21010 (United States); Durst, H. Dupont [R and T Directorate, Edgewood Chemical and Biological Center (ECBC), Aberdeen Proving Ground-Edgewood Area, MD 21010 (United States)

    2009-01-30

    A decontamination system for chemical warfare agents was developed and tested that combines a liquid decontamination reagent solution with solid sorbent particles. The components have fewer safety and environmental concerns than traditional chlorine bleach-based products or highly caustic solutions. The liquid solution, based on Decon Green{sup TM}, has hydrogen peroxide and a carbonate buffer as active ingredients. The best solid sorbents were found to be a copolymer of ethylene glycol dimethacrylate and n-lauryl methacrylate (Polytrap 6603 Adsorber); or an allyl methacrylate cross-linked polymer (Poly-Pore E200 Adsorber). These solids are human and environmentally friendly and are commonly used in cosmetics. The decontaminant system was tested for reactivity with pinacolyl methylphosphonofluoridate (Soman, GD), bis(2-chloroethyl)sulfide (Mustard, HD), and S-(2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) by using NMR Spectroscopy. Molybdate ion (MoO{sub 4}{sup -2}) was added to the decontaminant to catalyze the oxidation of HD. The molybdate ion provided a color change from pink to white when the oxidizing capacity of the system was exhausted. The decontaminant was effective for ratios of agent to decontaminant of up to 1:50 for VX (t{sub 1/2} {<=} 4 min), 1:10 for HD (t{sub 1/2} < 2 min with molybdate), and 1:10 for GD (t{sub 1/2} < 2 min). The vapor concentrations of GD above the dry sorbent and the sorbent with decontamination solution were measured to show that the sorbent decreased the vapor concentration of GD. The E200 sorbent had the additional advantage of absorbing aqueous decontamination solution without the addition of an organic co-solvent such as isopropanol, but the rate depended strongly on mixing for HD.

  3. A decontamination system for chemical weapons agents using a liquid solution on a solid sorbent

    International Nuclear Information System (INIS)

    Waysbort, Daniel; McGarvey, David J.; Creasy, William R.; Morrissey, Kevin M.; Hendrickson, David M.; Durst, H. Dupont

    2009-01-01

    A decontamination system for chemical warfare agents was developed and tested that combines a liquid decontamination reagent solution with solid sorbent particles. The components have fewer safety and environmental concerns than traditional chlorine bleach-based products or highly caustic solutions. The liquid solution, based on Decon Green TM , has hydrogen peroxide and a carbonate buffer as active ingredients. The best solid sorbents were found to be a copolymer of ethylene glycol dimethacrylate and n-lauryl methacrylate (Polytrap 6603 Adsorber); or an allyl methacrylate cross-linked polymer (Poly-Pore E200 Adsorber). These solids are human and environmentally friendly and are commonly used in cosmetics. The decontaminant system was tested for reactivity with pinacolyl methylphosphonofluoridate (Soman, GD), bis(2-chloroethyl)sulfide (Mustard, HD), and S-(2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) by using NMR Spectroscopy. Molybdate ion (MoO 4 -2 ) was added to the decontaminant to catalyze the oxidation of HD. The molybdate ion provided a color change from pink to white when the oxidizing capacity of the system was exhausted. The decontaminant was effective for ratios of agent to decontaminant of up to 1:50 for VX (t 1/2 ≤ 4 min), 1:10 for HD (t 1/2 1/2 < 2 min). The vapor concentrations of GD above the dry sorbent and the sorbent with decontamination solution were measured to show that the sorbent decreased the vapor concentration of GD. The E200 sorbent had the additional advantage of absorbing aqueous decontamination solution without the addition of an organic co-solvent such as isopropanol, but the rate depended strongly on mixing for HD

  4. Development of disposal sorbents for chloride removal from high-temperature coal-derived gases

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, G.N.; Wood, B.J.; Canizales, A. [and others

    1995-11-01

    The objective of this program is to develop alkali-based disposable sorbents capable of reducing HCl vapor concentrations to less than 1 ppmv in coal gas streams at temperatures in the range 400{degrees} to 750{degrees}C and pressures in the range 1 to 20 atm. The primary areas of focus of this program are investigation of different processes for fabricating the sorbents, testing their suitability for different reactor configurations, obtaining kinetic data for commercial reactor design, and updating the economics of the process.

  5. Potential for preparation of hot gas cleanup sorbents from spent hydroprocessing catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.; Biagini, M. [Canada Centre for Mineral and Energy Technology, Ottawa, ON (Canada). Energy Research Labs.

    1996-01-01

    Three spent-decoked hydroprocessing catalysts and two corresponding fresh catalysts were tested as hot gas clean-up sorbents and compared with the zinc ferrite using a simulated coal gasification gas mixture. The catalysts deposited only by coke exhibited relatively good cleaning efficiency. The catalyst deposited by coke and metals such as vanadium and nickel was less efficient. The useful life of the spent hydroprocessing catalysts may be extended if utilized as hot gas clean-up sorbents. 12 refs., 3 figs., 4 tabs.

  6. Experimentation of netlike hydro gel nitrogen containing polymer sorbents for biological liquids purification

    International Nuclear Information System (INIS)

    Karieva, Z.M.; Karimova, N. Kh.

    2003-01-01

    The high efficiency of hydrogels synthesized earlier in comparison with Pharmacopoeia sorbents are interesting to study comprehensively for the number of the toxins of biological liquids. Taking into considerations the high electoral sorption ability of ethynilpiperidol polymers to the hydro phobic interaction it may be suggested that they have a high detoxication ability. The detoxication characteristics of studied polymers have advantages over the known sorbents. Experiences with animals showed that in identical conditions of experiment in application of netlike polymers the survival grew 90%. Synthesis and investigations of netlike hydrogels polymer materials on nitrogen containing monomers of ethynil piperidol were given in the work. (author)

  7. Novel nanoporous sorbent for solid-phase extraction in petroleum fingerprinting

    Science.gov (United States)

    Alayande, S. Oluwagbemiga; Hlengilizwe, Nyoni; Dare, E. Olugbenga; Msagati, Titus A. M.; Akinlabi, A. Kehinde; Aiyedun, P. O.

    2016-04-01

    Sample preparation is crucial in the analysis of petroleum and its derivatives. In this study, developing affordable sorbent for petroleum fingerprinting analysis using polymer waste such expanded polystyrene was explored. The potential of electrospun expanded polystyrene (EPS) as a sorbent for the solid-phase extraction (SPE) technique was investigated, and its efficiency was compared with commercial cartridges such as alumina, silica and alumina/silica hybrid commercial for petroleum fingerprinting analysis. The chromatograms showed that the packed electrospun EPS fibre demonstrated excellent properties for SPE applications relative to the hybrid cartridges.

  8. Lanthanide Selective Sorbents: Self-Assembled Monolayers on Mesoporous Supports (SAMMS)

    Energy Technology Data Exchange (ETDEWEB)

    Fryxell, Glen E.; Wu, Hong; Lin, Yuehe; Shaw, Wendy J.; Birnbaum, Jerome C.; Linehan, John C.; Nie, Zimin; Kemner, Kenneth M.; Kelly, Shelley

    2004-11-01

    Through the marriage of mesoporous ceramics with self-assembled monolayer chemistry, the genesis of a powerful new class of environmental sorbent materials has been realized. By coating the mesoporous ceramic backbone with a monolayer terminated with a lanthanide-specific ligand, it is possible to couple high lanthanide binding affinity with the high loading capacity (resulting from the extremely high surface area of the support). This lanthanide-specific ligand field is created by pairing a “hard” anionic Lewis base with a suitable synergistic ligand, in a favorable chelating geometry. Details of the synthesis, characterization, lanthanide binding studies, binding kinetics, competition experiments and sorbent regeneration studies are summarized.

  9. Removal of H/sub 2/S from hot gas in the presence of Cu-containing sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Kyotani, T.; Kawashima, H.; Tomita, A.; Palmer, A.; Furimsky, E.

    1989-01-01

    Three solids containing Cu oxides were tested as sorbents for H/sub 2/S removal from hot gas at 600 degrees C. The formation of a surface layer of sulphides on pellet exterior affected Cu utilization for the sorbent prepared from Cu oxides alone. This improved for the sorbent prepared by impregnation of zeolite with Cu oxides, although complete utilization of Cu was not achieved. The combination of Cu oxides with SiO/sub 2/ gave the most efficient sorbent. Oxidation of H/sub 2/S to SO/sub 2/ on admission of hot gas to the fixed bed was a common observation for all sorbents. The addition of steam to hot gas suppressed the SO/sub 2/ formation. 9 refs., 6 figs., 4 tabs.

  10. Data summary report for M.W. Kellogg Z-sorb sorbent tests. CRADA 92-008 Final report

    Energy Technology Data Exchange (ETDEWEB)

    Everett, C E; Monaco, S J

    1994-05-01

    A series of tests were undertaken from August 6, 1992 through July 6, 1993 at METC`s High Pressure Bench-Scale Hot Gas Desulfurization Unit to support a Cooperative Research and Development Agreement (CRADA) between METC`s Sorbent Development Cluster and M.W. Kellogg. The M.W. Kellogg Company is currently developing a commercial offering of a hot gas clean-up system to be used in Integrated Gasification Combined Cycle (IGCC) systems. The intent of the CRADA agreement was to identify a suitable zinc-based desulfurization sorbent for the Sierra Pacific Power Company Clean Coal Technology Project, to identify optimum operating conditions for the sorbent, and to estimate potential sorbent loss per year. This report presents results pertaining to Phillips Petroleum`s Z-Sorb III sorbent.

  11. Use of programme theory to understand the differential effects of interventions across socio-economic groups in systematic reviews-a systematic methodology review.

    Science.gov (United States)

    Maden, Michelle; Cunliffe, Alex; McMahon, Naoimh; Booth, Andrew; Carey, Gina Michelle; Paisley, Suzy; Dickson, Rumona; Gabbay, Mark

    2017-12-29

    Systematic review guidance recommends the use of programme theory to inform considerations of if and how healthcare interventions may work differently across socio-economic status (SES) groups. This study aimed to address the lack of detail on how reviewers operationalise this in practice. A methodological systematic review was undertaken to assess if, how and the extent to which systematic reviewers operationalise the guidance on the use of programme theory in considerations of socio-economic inequalities in health. Multiple databases were searched from January 2013 to May 2016. Studies were included if they were systematic reviews assessing the effectiveness of an intervention and included data on SES. Two reviewers independently screened all studies, undertook quality assessment and extracted data. A narrative approach to synthesis was adopted. A total of 37 systematic reviews were included, 10 of which were explicit in the use of terminology for 'programme theory'. Twenty-nine studies used programme theory to inform both their a priori assumptions and explain their review findings. Of these, 22 incorporated considerations of both what and how interventions do/do not work in SES groups to both predict and explain their review findings. Thirteen studies acknowledged 24 unique theoretical references to support their assumptions of what or how interventions may have different effects in SES groups. Most reviewers used supplementary evidence to support their considerations of differential effectiveness. The majority of authors outlined a programme theory in the "Introduction" and "Discussion" sections of the review to inform their assumptions or provide explanations of what or how interventions may result in differential effects within or across SES groups. About a third of reviews used programme theory to inform the review analysis and/or synthesis. Few authors used programme theory to inform their inclusion criteria, data extraction or quality assessment. Twenty

  12. SO{sub 2} retention by reactivated CaO-based sorbent from multiple CO{sub 2} capture cycles

    Energy Technology Data Exchange (ETDEWEB)

    Vasilije Manovic; Edward J. Anthony [CANMET Energy Technology Centre-Ottawa, Ottawa, ON (Canada). Natural Resources Canada

    2007-06-15

    This paper examines the reactivation of spent sorbent, produced from multiple CO{sub 2} capture cycles, for use in SO{sub 2} capture. CaO-based sorbent samples were obtained from Kelly Rock limestone using three particle size ranges, each containing different impurities levels. Using a thermogravimetric analyzer (TGA), the sulfation behavior of partially sulfated and unsulfated samples obtained after multiple calcination-carbonation cycles in a tube furnace (TF), following steam reactivation in a pressurized reactor, is examined. In addition, samples calcined/sintered under different conditions after hydration are also examined. The results show that suitably treated spent sorbent has better sulfation characteristics than that of the original sorbent. Thus for example, after 2 h sulfation, {gt} 80% of the CaO was sulfated. In addition, the sorbent showed significant activity even after 4 h when {gt} 95% CaO was sulfated. The results were confirmed by X-ray diffraction (XRD) analysis, which showed that, by the end of the sulfation process, samples contained CaSO{sub 4} with only traces of unreacted CaO. The superior behavior of spent reactivated sorbent appears to be due to swelling of the sorbent particles during steam hydration. The surface area morphology of sorbent after reactivation was examined by scanning electron microscopy (SEM). Ca(OH){sub 2} crystals were seen, which displayed their regular shape, and their elemental composition was confirmed by energy-dispersive X-ray (EDX) analysis. These results allow the proposal of a new process for the use of CaO-based sorbent in fluidized bed combustion (FBC) systems, which incorporates CO{sub 2} capture, sorbent reactivation, and SO{sub 2} retention. 26 refs., 4 figs., 2 tabs.

  13. SO{sub 2} Retention by CaO-Based Sorbent Spent in CO{sub 2} Looping Cycles

    Energy Technology Data Exchange (ETDEWEB)

    Manovic, V.; Anthony, E.J.; Loncarevic, D.

    2009-07-15

    CaO-based looping cycles are promising processes for CO{sub 2} Capture from both syngas and flue gas. The technology is based on cyclical carbonation of CaO and regeneration of CaCO{sub 3} in a dual fluidized-bed reactor to produce a pure CO{sub 2} stream suitable for sequestration. Use of spent sorbent from CO{sub 2} looping cycles for SO{sub 2} capture is investigated. Three limestones were investigated: Kelly Rock (Canada), La Blanca (Spain), and Katowice (Poland, Upper Silesia). Carbonation/calcination cycles were performed in a tube furnace with both the original limestones and samples thermally pretreated for different times (i.e., sintered). The spent sorbent samples were sulfated in a thermogravimetric analyzer (TGA). The changes in the resulting sorbent pore structure were then investigated using mercury porosimetry. It has been shown that the sulfation rates of both thermally pretreated and spent sorbent samples are lower in comparison with those of the original samples. However, final conversions of both spent and pretreated sorbents after longer sulfation time were comparable or higher than those observed for the original sorbents under comparable conditions. Maximum sulfation levels strongly depend on sorbent porosity and pore surface area. The results showed that spent sorbent samples from CO{sub 2} looping cycles can be used as sorbents for SO{sub 2} retention in cases where significant porosity loss does not occur during CO{sub 2} reaction cycles. In the case of spent Kelly Rock and Katowice samples, sorbent particles are practically uniformly sulfated, achieving final conversions that are determined by the total pore volume available for the bulky CaSO{sub 4} product.

  14. Study of the factors affecting the performance of microextraction by packed sorbent (MEPS) using liquid scintillation counter and liquid chromatography-tandem mass spectrometry

    International Nuclear Information System (INIS)

    Altun, Zeki; Abdel-Rehim, Mohamed

    2008-01-01

    Microextraction by packed sorbent (MEPS) is a new technique for sample preparation that can be connected on-line with LC or GC. In MEPS, approximately 1-2 mg of the solid packing material is inserted into a syringe (100-250 μL) as a plug. Sample preparation takes place on the packed bed. The bed can be packed or coated to provide selective and suitable sampling conditions. The new method is very promising for extraction of drugs and metabolites from biological samples. In this paper, some factors affecting the performance of MEPS such as recovery, carry-over, leakage, washing volume and elution volume were studied using C18 and hydroxylated polystyrene-divinylbenzene copolymer (ENV+) as sorbents. Radioactively labelled bupivacaine in plasma samples was used as test analyte. For the extraction of this drug, using methanol/water 95:5 (v/v) (0.25% ammonium hydroxide) was used as elution solvent. The analyte response increased with increasing the elution volume and it was linear upp up to 100 μL utilizing liquid scintillation counter. Further, for concentrating the sample, we found that MEPS may be used such that the sample can be drawn through the needle, up and down, several times. The analyte leakage increases as the volume washing increases, though higher washing volumes may also result in cleaner extracts. To eliminate analyte carry-over, the sorbents were washed first with 3 x 250 μL elution solution and then with 3 x 250 μL washing solution. In addition, the reproducibility measurements show relatively good relative standard deviation (RSD) % values concerning analyte recovery and analyte leakage. The present study provides an understanding of basic aspects when optimizing methods for MEPS. In this study, MEPS was used off-line with liquid scintillation counter and on-line with LC-MS/MS

  15. Study of the factors affecting the performance of microextraction by packed sorbent (MEPS) using liquid scintillation counter and liquid chromatography-tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Altun, Zeki [Karlstad University, Faculty of Technology and Science, SE-651 88 Karlstad (Sweden); Abdel-Rehim, Mohamed [Karlstad University, Faculty of Technology and Science, SE-651 88 Karlstad (Sweden); Clinical Pharmacology and DMPK, AstraZeneca R and D Soedertaelje, SE-151 85 Soedertaelje (Sweden)], E-mail: Mohamed.Abdel-Rehim@Astrazeneca.com

    2008-12-23

    Microextraction by packed sorbent (MEPS) is a new technique for sample preparation that can be connected on-line with LC or GC. In MEPS, approximately 1-2 mg of the solid packing material is inserted into a syringe (100-250 {mu}L) as a plug. Sample preparation takes place on the packed bed. The bed can be packed or coated to provide selective and suitable sampling conditions. The new method is very promising for extraction of drugs and metabolites from biological samples. In this paper, some factors affecting the performance of MEPS such as recovery, carry-over, leakage, washing volume and elution volume were studied using C18 and hydroxylated polystyrene-divinylbenzene copolymer (ENV+) as sorbents. Radioactively labelled bupivacaine in plasma samples was used as test analyte. For the extraction of this drug, using methanol/water 95:5 (v/v) (0.25% ammonium hydroxide) was used as elution solvent. The analyte response increased with increasing the elution volume and it was linear upp up to 100 {mu}L utilizing liquid scintillation counter. Further, for concentrating the sample, we found that MEPS may be used such that the sample can be drawn through the needle, up and down, several times. The analyte leakage increases as the volume washing increases, though higher washing volumes may also result in cleaner extracts. To eliminate analyte carry-over, the sorbents were washed first with 3 x 250 {mu}L elution solution and then with 3 x 250 {mu}L washing solution. In addition, the reproducibility measurements show relatively good relative standard deviation (RSD) % values concerning analyte recovery and analyte leakage. The present study provides an understanding of basic aspects when optimizing methods for MEPS. In this study, MEPS was used off-line with liquid scintillation counter and on-line with LC-MS/MS.

  16. A Service evaluation of a hospital child death review process to elucidate understanding of contributory factors to child mortality and inform practice in the English National Health Service.

    Science.gov (United States)

    Magnus, Daniel S; Schindler, Margrid B; Marlow, Robin D; Fraser, James I

    2018-03-16

    To describe a novel approach to hospital mortality meetings to elucidate understanding of contributory factors to child death and inform practice in the National Health Service. All child deaths were separately reviewed at a meeting attended by professionals across the healthcare pathway, and an assessment was made of contributory factors to death across domains intrinsic to the child, family and environment, parenting capacity and service delivery. Data were analysed from a centrally held database of records. All child deaths in a tertiary children's hospital between 1 April 2010 and 1 April 2013. Descriptive data summarising contributory factors to child deaths. 95 deaths were reviewed. In 85% cases, factors intrinsic to the child provided complete explanation for death. In 11% cases, factors in the family and environment and, in 5% cases, factors in parenting capacity, contributed to patient vulnerability. In 33% cases, factors in service provision contributed to patient vulnerability and in two patients provided complete explanation for death. 26% deaths were classified as potentially preventable and in those cases factors in service provision were more commonly identified than factors across other domains (OR: 4.89; 95% CI 1.26 to 18.9). Hospital child death review meetings attended by professionals involved in patient management across the healthcare pathway inform understanding of events leading to a child's death. Using a bioecological approach to scrutinise contributory factors the multidisciplinary team concluded most deaths occurred as a consequence of underlying illness. Although factors relating to service provision were commonly identified, they rarely provided a complete explanation for death. Efforts to reduce child mortality should be driven by an understanding of modifiable risk factors. Systematic data collection arising from a standardised approach to hospital reviews should be the basis for national mortality review processes and database

  17. Mercury Removal from MSW Incineration Flue Gas by Mineral-based Sorbents.

    Czech Academy of Sciences Publication Activity Database

    Rumayor, Marta; Svoboda, Karel; Švehla, Jaroslav; Pohořelý, Michael; Šyc, Michal

    2018-01-01

    Roč. 73, DEC 13 (2018), s. 265-270 ISSN 0956-053X R&D Projects: GA TA ČR TE02000236 Institutional support: RVO:67985858 Keywords : mercury * removal * mineral sorbents Subject RIV: DI - Air Pollution ; Quality OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 4.030, year: 2016

  18. Anaerobic co-digestion of cork based oil sorbent and cow manure or sludge

    NARCIS (Netherlands)

    Cavaleiro, A.J.; Neves, T.M.; Guedes, A.P.; Alves, M.M.; Pinto, P.; Silva, S.P.; Machado de Sousa, Diana

    2015-01-01

    Cork, a material with great economic, social and environmental importance in Portugal, is also a good oil sorbent that can be used in the remediation of oil spills. The oil-impregnated cork can be easily removed, but requires further treatment. In the case of vegetable oil spills, anaerobic

  19. Water Utility Lime Sludge Reuse – An Environmental Sorbent for Power Utilities

    Science.gov (United States)

    Lime sludge can be used as an environmental sorbent to remove sulfur dioxide (SO2) and acid gases, by the ultra-fine CaCO3 particles, and to sequester mercury and other heavy metals, by the Natural Organic Matter and residual activated carbon. The laboratory experimental set up ...

  20. ACTIVATION AND REACTIVITY OF NOVEL CALCIUM-BASED SORBENTS FOR DRY SO2 CONTROL IN BOILERS

    Science.gov (United States)

    Chemically modified calcium hydroxide (Ca(OH)2) sorbents developed in the U.S. Environmental Protection Agency's Air and Energy Engineering Research Laboratory (AEERL) for sulfur dioxide (SO2) control in utility boilers were tested in an electrically heated, bench-scale isotherma...

  1. High temperature capture of CO2 on lithium-based sorbents from rice husk ash.

    Science.gov (United States)

    Wang, Ke; Guo, Xin; Zhao, Pengfei; Wang, Fanzi; Zheng, Chuguang

    2011-05-15

    Highly efficient Li(4)SiO(4) (lithium orthosilicate)-based sorbents for CO(2) capture at high temperature, was developed using waste materials (rice husk ash). Two treated rice husk ash (RHA) samples (RHA1 and RHA2) were prepared and calcined at 800°C in the presence of Li(2)CO(3). Pure Li(4)SiO(4) and RHA-based sorbents were characterized by X-ray fluorescence, X-ray diffraction, scanning electron microscopy, nitrogen adsorption, and thermogravimetry. CO(2) sorption was tested through 15 carbonation/calcination cycles in a fixed bed reactor. The metals of RHA were doped with Li(4)SiO(4) resulting to inhibited growth of the particles and increased pore volume and surface area. Thermal analyses indicated a much better CO(2) absorption in Li(4)SiO(4)-based sorbent prepared from RHA1 (higher metal content sample) because the activation energies for the chemisorption process and diffusion process were smaller than that of pure Li(4)SiO(4). RHA1-based sorbent also maintained higher capacities during the multiple cycles. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Technical task plan for testing filter box sorbent-paint filter test

    International Nuclear Information System (INIS)

    Kilpatrick, L.L.

    1993-01-01

    At the Savannah River Plant, High Level Waste Engineering (HLWE) asked Interim Waste Technology (IWT) to choose and test a sorbent to add to the ITP filter box that meets the EPA requirement for land disposal of containerized liquid hazardous wastes per Paint Filter Liquids (PFL) test method 9095. This report outlines the process to be used in accomplishing this task

  3. A highly efficient and selective polysilsesquioxane sorbent for heavy metal removal

    KAUST Repository

    Duan, Xiaonan; Qi, Genggeng; Wang, Peng; Giannelis, Emmanuel P.

    2012-01-01

    Suited for heavy stuff: An efficient mesoporous sorbent based on a pure ethylendiamine-bridged polysilsesquioxane is presented. This material, with both a high amine loading and a high surface area, is applied for heavy metal ion removal. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Regeneration dynamics of potassium-based sediment sorbents for CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Li-wei; Diao, Yong-fa; Wang, Lin-lin; Shi, Xiao-fang; Tai, Xiao-yan [Donghua University, Shanghai (China)

    2013-08-15

    Simulating regeneration tests of Potassium-Based sorbents that supported by Suzhou River Channel Sediment were carried out in order to obtain parameters of regeneration reaction. Potassium-based sediment sorbents have a better morphology with the surface area of 156.73 m{sup 2}·g{sup −1}, the pore volume of 357.5x10{sup −3} cm{sup 3}·g{sup −1} and the distribution of pore diameters about 2-20 nm. As a comparison, those of hexagonal potassium-based sorbents are only 2.83 m{sup 2}g{sup −1}, 7.45x10{sup −3} cm{sup 3}g{sup −1} and 1.72-5.4 nm, respectively. TGA analysis shows that the optimum final temperature of regeneration is 200 and the optimum loading is about 40%, with the best heating rate of 10 .deg. C·min{sup −1}. By the modified Coats-Redfern integral method, the activation energy of 40% KHCO{sub 3} sorbents is 102.43 kJ·mol{sup −1}. The results obtained can be used as basic data for designing and operating CO{sub 2} capture process.

  5. CO2 removal from biogas with supported amine sorbents : First technical evaluation based on experimental data

    NARCIS (Netherlands)

    Sutanto, Stevia; Dijkstra, J. W.; Pieterse, J. A.Z.; Boon, J; Hauwert, P.; Brilman, D. W.F.

    2017-01-01

    Biogas from fermentation of manure and organic residues produces a gas stream that can be fed into the natural gas grid, provided impurities (CO2, H2S and H2O) are removed according to specifications prior to grid injection. Compared to conventional technologies, supported amine sorbents (SAS) seem

  6. Adsorption of gaseous RuO4 by various sorbents. II

    International Nuclear Information System (INIS)

    Vujisic, L.; Nikolic, R.

    1983-01-01

    Sorption of gaseous RuO 4 on impregnated Alcoa Alumina H-151, impregnated charcoal, silica gel and HEPA filter was investigated. The results obtained on various sorbents are compared and discussed in connection with possibilities to use the chosen material in air cleaning systems

  7. Mercury Removal from MSW Incineration Flue Gas by Mineral-based Sorbents.

    Czech Academy of Sciences Publication Activity Database

    Rumayor, Marta; Svoboda, Karel; Švehla, Jaroslav; Pohořelý, Michael; Šyc, Michal

    Roč. 73, DEC 13 ( 2018 ), s. 265-270 ISSN 0956-053X R&D Projects: GA TA ČR TE02000236 Institutional support: RVO:67985858 Keywords : mercury * removal * mineral sorbents Subject RIV: DI - Air Pollution ; Quality OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 4.030, year: 2016

  8. Microbial consortia in mesocosm bioremediation trial using oil sorbents, slow-release fertilizer and bioaugmentation.

    Science.gov (United States)

    Gertler, Christoph; Gerdts, Gunnar; Timmis, Kenneth N; Golyshin, Peter N

    2009-08-01

    An experimental prototype oil boom including oil sorbents, slow-release fertilizers and biomass of the marine oil-degrading bacterium, Alcanivorax borkumensis, was applied for sorption and degradation of heavy fuel oil in a 500-L mesocosm experiment. Fingerprinting of DNA and small subunit rRNA samples for microbial activity conducted to study the changes in microbial communities of both the water body and on the oil sorbent surface showed the prevalence of A. borkumensis on the surface of the oil sorbent. Growth of this obligate oil-degrading bacterium on immobilized oil coincided with a 30-fold increase in total respiration. A number of DNA and RNA signatures of aromatic hydrocarbon-degrading bacteria were detected both in samples of water body and on oil sorbent. Ultimately, the heavy fuel oil in this mesocosm study was effectively removed from the water body. This is the first study to successfully investigate the fate of oil-degrading microbial consortia in an experimental prototype for a bioremediation strategy in offshore, coastal or ship-bound oil spill mitigation using a combination of mechanical and biotechnological techniques.

  9. 77 FR 9610 - Gastroenterology-Urology Devices; Reclassification of Sorbent Hemoperfusion Devices for the...

    Science.gov (United States)

    2012-02-17

    ... encephalopathy, a complication of liver failure in which the brain function progressively deteriorates. Hepatic encephalopathy is a condition in which toxic substances that are normally cleared from the body by the liver... encephalopathy, at which the disturbance of the brain function leads to loss of consciousness. Sorbent...

  10. Recovery of Lithium from Geothermal Brine with Lithium-Aluminum Layered Double Hydroxide Chloride Sorbents.

    Science.gov (United States)

    Paranthaman, Mariappan Parans; Li, Ling; Luo, Jiaqi; Hoke, Thomas; Ucar, Huseyin; Moyer, Bruce A; Harrison, Stephen

    2017-11-21

    We report a three-stage bench-scale column extraction process to selectively extract lithium chloride from geothermal brine. The goal of this research is to develop materials and processing technologies to improve the economics of lithium extraction and production from naturally occurring geothermal and other brines for energy storage applications. A novel sorbent, lithium aluminum layered double hydroxide chloride (LDH), is synthesized and characterized with X-ray powder diffraction, scanning electron microscopy, inductively coupled plasma optical emission spectrometry (ICP-OES), and thermogravimetric analysis. Each cycle of the column extraction process consists of three steps: (1) loading the sorbent with lithium chloride from brine; (2) intermediate washing to remove unwanted ions; (3) final washing for unloading the lithium chloride ions. Our experimental analysis of eluate vs feed concentrations of Li and competing ions demonstrates that our optimized sorbents can achieve a recovery efficiency of ∼91% and possess excellent Li apparent selectivity of 47.8 compared to Na ions and 212 compared to K ions, respectively in the brine. The present work demonstrates that LDH is an effective sorbent for selective extraction of lithium from brines, thus offering the possibility of effective application of lithium salts in lithium-ion batteries leading to a fundamental shift in the lithium supply chain.

  11. Catalyst functionalized buffer sorbent pebbles for rapid separation of carbon dioxide from gas mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Aines, Roger D

    2015-03-31

    A method for separating CO.sub.2 from gas mixtures uses a slurried media impregnated with buffer compounds and coating the solid media with a catalyst or enzyme that promotes the transformation of CO.sub.2 to carbonic acid. Buffer sorbent pebbles with a catalyst or enzyme coating are provided for rapid separation of CO.sub.2 from gas mixtures.

  12. A highly efficient and selective polysilsesquioxane sorbent for heavy metal removal

    KAUST Repository

    Duan, Xiaonan

    2012-02-29

    Suited for heavy stuff: An efficient mesoporous sorbent based on a pure ethylendiamine-bridged polysilsesquioxane is presented. This material, with both a high amine loading and a high surface area, is applied for heavy metal ion removal. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Feasibility Study of Commercial Sorbent in Coal-derived Syngas Desulfurization Field.

    Czech Academy of Sciences Publication Activity Database

    Chien, H.-Y.; Chyou, Y.-P.; Svoboda, Karel

    2015-01-01

    Roč. 6, č. 4 (2015), s. 236-242 ISSN 2078-0737 R&D Projects: GA ČR GC14-09692J Grant - others:MOST(TW) NSC 103-2923-E-042A-001 -MY3 Institutional support: RVO:67985858 Keywords : gasification * desulfurization * sorbent Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  14. Theoretical evaluation on selective adsorption characteristics of alkali metal-based sorbents for gaseous oxidized mercury.

    Science.gov (United States)

    Tang, Hongjian; Duan, Yufeng; Zhu, Chun; Cai, Tianyi; Li, Chunfeng; Cai, Liang

    2017-10-01

    Alkali metal-based sorbents are potential for oxidized mercury (Hg 2+ ) selective adsorption but show hardly effect to elemental mercury (Hg 0 ) in flue gas. Density functional theory (DFT) was employed to investigate the Hg 0 and HgCl 2 adsorption mechanism over alkali metal-based sorbents, including calcium oxide (CaO), magnesium oxide (MgO), potassium chloride (KCl) and sodium chloride (NaCl). Hg 0 was found to weakly interact with CaO (001), MgO (001), KCl (001) and NaCl (001) surfaces while HgCl 2 was effectively adsorbed on top-O and top-Cl sites. Charge transfer and bond population were calculated to discuss the covalency and ionicity of HgCl 2 bonding with the adsorption sites. The partial density of states (PDOS) analysis manifests that HgCl 2 strongly interacts with surface sites through the orbital hybridizations between Hg and top O or Cl. Frontier molecular orbital (FMO) energy and Mulliken electronegativity are introduced as the quantitative criteria to evaluate the reactivity of mercury species and alkali metal-based sorbents. HgCl 2 is identified as a Lewis acid and more reactive than Hg 0 . The Lewis basicity of the four alkali metal-based sorbents is predicted as the increasing order: NaCl < MgO < KCl < CaO, in consistence with the trend of HgCl 2 adsorption energies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Catalyst functionalized buffer sorbent pebbles for rapid separation of carbon dioxide from gas mixtures

    Science.gov (United States)

    Aines, Roger D.

    2013-03-12

    A method for separating CO.sub.2 from gas mixtures uses a slurried media impregnated with buffer compounds and coating the solid media with a catalyst or enzyme that promotes the transformation of CO.sub.2 to carbonic acid. Buffer sorbent pebbles with a catalyst or enzyme coating are provided for rapid separation of CO.sub.2 from gas mixtures.

  16. A decontamination system for chemical weapons agents using a liquid solution on a solid sorbent.

    Science.gov (United States)

    Waysbort, Daniel; McGarvey, David J; Creasy, William R; Morrissey, Kevin M; Hendrickson, David M; Durst, H Dupont

    2009-01-30

    A decontamination system for chemical warfare agents was developed and tested that combines a liquid decontamination reagent solution with solid sorbent particles. The components have fewer safety and environmental concerns than traditional chlorine bleach-based products or highly caustic solutions. The liquid solution, based on Decon Greentrade mark, has hydrogen peroxide and a carbonate buffer as active ingredients. The best solid sorbents were found to be a copolymer of ethylene glycol dimethacrylate and n-lauryl methacrylate (Polytrap 6603 Adsorber); or an allyl methacrylate cross-linked polymer (Poly-Pore E200 Adsorber). These solids are human and environmentally friendly and are commonly used in cosmetics. The decontaminant system was tested for reactivity with pinacolyl methylphosphonofluoridate (Soman, GD), bis(2-chloroethyl)sulfide (Mustard, HD), and S-(2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) by using NMR Spectroscopy. Molybdate ion (MoO(4)(-2)) was added to the decontaminant to catalyze the oxidation of HD. The molybdate ion provided a color change from pink to white when the oxidizing capacity of the system was exhausted. The decontaminant was effective for ratios of agent to decontaminant of up to 1:50 for VX (t(1/2) decontamination solution were measured to show that the sorbent decreased the vapor concentration of GD. The E200 sorbent had the additional advantage of absorbing aqueous decontamination solution without the addition of an organic co-solvent such as isopropanol, but the rate depended strongly on mixing for HD.

  17. Super-Hydrophobic High Throughput Electrospun Cellulose Acetate (CA) Nanofibrous Mats as Oil Selective Sorbents

    Science.gov (United States)

    Han, Chao

    The threat of oil pollution increases with the expansion of oil exploration and production activities, as well as the industrial growth around the world. Use of sorbents is a common method to deal with the oil spills. In this work, an advanced sorbent technology is described. A series of non-woven Cellulose Acetate (CA) nanofibrous mats with a 3D fibrous structure were synthesized by a novel high-throughput electrospinning technique. The precursor was solutions of CA/ acetic acid-acetone in various concentrations. Among them, 15.0% CA exhibits a superhydrophobic surface property, with a water contact angle of 128.95°. Its oil sorption capacity is many times higher the oil sorption capacity of the best commercial sorbent available in the market. Also, it showed good buoyancy properties on the water both as dry-mat and oil-saturated mat. In addition, it is biodegradable, easily available, easily manufactured, so the CA nanofibrous mat is an excellent candidate as oil sorbent for oil spill in water treatment.

  18. Monolithic columns with organic sorbent based on poly-1-vinylimidazole for high performance liquid chromatography

    Science.gov (United States)

    Patrushev, Y. V.; Sidelnikov, V. N.; Yudina, Y. S.

    2017-03-01

    Monolithic chromatographic columns for HPLC with sorbent based on 1-vinylimidazole are prepared. It is shown that changing the 1-vinylimidazole content in the initial solution allows us to change the polarity of columns. An example of aromatic hydrocarbons separation is presented.

  19. Adsorption of CO2 and H2O on supported amine sorbents

    NARCIS (Netherlands)

    Veneman, Rens; Zhao, W.; Li, Z.; Cai, N.; Brilman, Derk Willem Frederik

    2014-01-01

    In this work we have evaluated the H2O and CO2 adsorption characteristics of Lewatit VP OC 1065 in view of the potential application of solid sorbents in post combustion CO2 capture. Here we present single component adsorption isotherms for H2O and CO2 as well as co-adsorption experiments. It was

  20. Electrostatic interactions between immunoglobulin (IgG) molecules and a charged sorbent

    NARCIS (Netherlands)

    Bremer, M.G.E.G.; Duval, J.; Norde, Willem; Lyklema, J.

    2004-01-01

    The influence of electrostatic interactions on the adsorption of IgG is examined both theoretically and experimentally. The long-range interaction between IgG and the charged sorbent surface is treated in terms of the DLVO theory taking into account the possibility of charge- and potential

  1. CO_2 capture with solid sorbent: CFD model of an innovative reactor concept

    International Nuclear Information System (INIS)

    Barelli, L.; Bidini, G.; Gallorini, F.

    2016-01-01

    Highlights: • A new reactor solution based on rotating fixed beds was presented. • The preliminary design of the reactor was approached. • A CFD model of the reactor, including CO_2 capture kinetic, was developed. • The CFD model is validated with experimental results. • Sorbent exploitation increasing is possible thanks to the new reactor. - Abstract: In future decarbonization scenarios, CCS with particular reference to post-combustion technologies will be an important option also for energy intensive industries. Nevertheless, today CCS systems are rarely installed due to high energy and cost penalties of current technology based on chemical scrubbing with amine solvent. Therefore, innovative solutions based on new/optimized solvents, sorbents, membranes and new process designs, are R&D priorities. Regarding the CO_2 capture through solid sorbents, a new reactor solution based on rotating fixed beds is presented in this paper. In order to design the innovative system, a suitable CFD model was developed considering also the kinetic capture process. The model was validated with experimental results obtained by the authors in previous research activities, showing a potential reduction of energy penalties respect to current technologies. In the future, the model will be used to identify the control logic of the innovative reactor in order to verify improvements in terms of sorbent exploitation and reduction of system energy consumption.

  2. Understanding Resilience

    Directory of Open Access Journals (Sweden)

    Gang eWu

    2013-02-01

    Full Text Available Resilience is the ability to adapt successfully in the face of stress and adversity. Stressful life events, trauma and chronic adversity can have a substantial impact on brain function and structure, and can result in the development of PTSD, depression and other psychiatric disorders. However, most individuals do not develop such illnesses after experiencing stressful life events, and are thus thought to be resilient. Resilience as successful adaptation relies on effective responses to environmental challenges and ultimate resistance to the deleterious effects of stress, therefore a greater understanding of the factors that promote such effects is of great relevance. This review focuses on recent findings regarding genetic, epigenetic, developmental, psychosocial and neurochemical factors that are considered essential contributors to the development of resilience. Neural circuits and pathways involved in mediating resilience are also discussed. The growing understanding of resilience factors will hopefully lead to the development of new pharmacological and psychological interventions for enhancing resilience and mitigating the untoward consequences.

  3. Understanding low levels of physical activity in people with intellectual disabilities : A systematic review to identify barriers and facilitators

    NARCIS (Netherlands)

    Bossink, Leontien; van der Putten, Annette; Vlaskamp, Carla

    2017-01-01

    Background: People with intellectual disabilities (ID) undertake extremely low levels of physical activity. Aims: To enhance understanding concerning low levels of physical activity in people with ID, this study has three aims: (1) to identify barriers to and facilitators of physical activity in

  4. Lead, Chromium and Cadmium Removal from Contaminated Water Using Phosphate Sorbents

    Directory of Open Access Journals (Sweden)

    Fariborz Riahi

    2010-06-01

    Full Text Available Sorption of 3 poisonous metal ions (Pb2+, Cd2+, Cr3+ in aqueous solutions by two phosphate sorbents under dynamic and static conditions was studied. Phosphate sorbents (MgNH4PO4. H2O, Mg3(PO42. 6H2O were synthesized by known procedures. The resulting crystalline samples were analyzed for the contents of Mg2+, Pb2+, P, N using spectrophotometric and elemental analysis methods. Likewise, the amounts of Pb2+, Cd2+, Cr3+ in solutions were determined before and after the sorption process using the atomic absorption method. The relative standard deviations for Pb2+, Cd2+, Cr3+ were 4.7%, 2.17%, and 1.61% and the detection limits were 5 g/L, 0.05 mg/L, and 0.1 mg/L, respectively. The sorbents showed a high performance in the purification of contaminated solutions under static conditions. The sorption capacity levels of Mg3 (PO42. 6H2O and MgNH4 PO4. H2O were 9.8m.mol/gr and 8.9m.mol/gr for Pb2+; 10.5m.mol/gr and 9m.mol/gr for Cd2+; and 6.6m.mol/gr and 5.3m.mol/gr for Cr3+, respectively. Pb2+ , Cd2+, Cr3+. sorption by inorganic phosphate sorbents from solutions is associated with complicated chemical transformations of the sorbents. A proper account of these transformations allows for the sorption process to be optimized. The data on Pb2+, Cd2+, Cr3+ sorption under static conditions (24-h contact of Mg3 (PO42. 6H2O, MgNH4PO4. H2O, with solutions at 20oC and under dynamic conditions were obtained and the sorption behaviors of the metal ions were investigated in response to the sorbents used. It was found that Mg3 (PO42. 6H2O was the best sorbent for Pb2+, Cd2+, Cr3+ under dynamic conditions.

  5. Thermally moderated hollow fiber sorbent modules in rapidly cycled pressure swing adsorption mode for hydrogen purification

    KAUST Repository

    Lively, Ryan P.; Bessho, Naoki; Bhandari, Dhaval A.; Kawajiri, Yoshiaki; Koros, William J.

    2012-01-01

    We describe thermally moderated multi-layered pseudo-monolithic hollow fiber sorbents entities, which can be packed into compact modules to provide small-footprint, efficient H2 purification/CO2 removal systems for use in on-site steam methane reformer product gas separations. Dual-layer hollow fibers are created via dry-jet, wet-quench spinning with an inner "active" core of cellulose acetate (porous binder) and zeolite NaY (69 wt% zeolite NaY) and an external sheath layer of pure cellulose acetate. The co-spun sheath layer reduces the surface porosity of the fiber and was used as a smooth coating surface for a poly(vinyl-alcohol) post-treatment, which reduced the gas permeance through the fiber sorbent by at least 7 orders of magnitude, essentially creating an impermeable sheath layer. The interstitial volume between the individual fibers was filled with a thermally-moderating paraffin wax. CO2 breakthrough experiments on the hollow fiber sorbent modules with and without paraffin wax revealed that the "passively" cooled paraffin wax module had 12.5% longer breakthrough times than the "non-isothermal" module. The latent heat of fusion/melting of the wax offsets the released latent heat of sorption/desorption of the zeolites. One-hundred rapidly cycled pressure swing adsorption cycles were performed on the "passively" cooled hollow fiber sorbents using 25 vol% CO2/75 vol% He (H2 surrogate) at 60 °C and 113 psia, resulting in a product purity of 99.2% and a product recovery of 88.1% thus achieving process conditions and product quality comparable to conventional pellet processes. Isothermal and non-isothermal dynamic modeling of the hollow fiber sorbent module and a traditional packed bed using gPROMS® indicated that the fiber sorbents have sharper fronts (232% sharper) and longer adsorbate breakthrough times (66% longer), further confirming the applicability of the new fiber sorbent approach for H2 purification. © 2012, Hydrogen Energy Publications, LLC

  6. Thermally moderated hollow fiber sorbent modules in rapidly cycled pressure swing adsorption mode for hydrogen purification

    KAUST Repository

    Lively, Ryan P.

    2012-10-01

    We describe thermally moderated multi-layered pseudo-monolithic hollow fiber sorbents entities, which can be packed into compact modules to provide small-footprint, efficient H2 purification/CO2 removal systems for use in on-site steam methane reformer product gas separations. Dual-layer hollow fibers are created via dry-jet, wet-quench spinning with an inner "active" core of cellulose acetate (porous binder) and zeolite NaY (69 wt% zeolite NaY) and an external sheath layer of pure cellulose acetate. The co-spun sheath layer reduces the surface porosity of the fiber and was used as a smooth coating surface for a poly(vinyl-alcohol) post-treatment, which reduced the gas permeance through the fiber sorbent by at least 7 orders of magnitude, essentially creating an impermeable sheath layer. The interstitial volume between the individual fibers was filled with a thermally-moderating paraffin wax. CO2 breakthrough experiments on the hollow fiber sorbent modules with and without paraffin wax revealed that the "passively" cooled paraffin wax module had 12.5% longer breakthrough times than the "non-isothermal" module. The latent heat of fusion/melting of the wax offsets the released latent heat of sorption/desorption of the zeolites. One-hundred rapidly cycled pressure swing adsorption cycles were performed on the "passively" cooled hollow fiber sorbents using 25 vol% CO2/75 vol% He (H2 surrogate) at 60 °C and 113 psia, resulting in a product purity of 99.2% and a product recovery of 88.1% thus achieving process conditions and product quality comparable to conventional pellet processes. Isothermal and non-isothermal dynamic modeling of the hollow fiber sorbent module and a traditional packed bed using gPROMS® indicated that the fiber sorbents have sharper fronts (232% sharper) and longer adsorbate breakthrough times (66% longer), further confirming the applicability of the new fiber sorbent approach for H2 purification. © 2012, Hydrogen Energy Publications, LLC

  7. Using sorbent waste materials to enhance treatment of micro-point source effluents by constructed wetlands

    Science.gov (United States)

    Green, Verity; Surridge, Ben; Quinton, John; Matthews, Mike

    2014-05-01

    Sorbent materials are widely used in environmental settings as a means of enhancing pollution remediation. A key area of environmental concern is that of water pollution, including the need to treat micro-point sources of wastewater pollution, such as from caravan sites or visitor centres. Constructed wetlands (CWs) represent one means for effective treatment of wastewater from small wastewater producers, in part because they are believed to be economically viable and environmentally sustainable. Constructed wetlands have the potential to remove a range of pollutants found in wastewater, including nitrogen (N), phosphorus (P), biochemical oxygen demand (BOD) and carbon (C), whilst also reducing the total suspended solids (TSS) concentration in effluents. However, there remain particular challenges for P and N removal from wastewater in CWs, as well as the sometimes limited BOD removal within these treatment systems, particularly for micro-point sources of wastewater. It has been hypothesised that the amendment of CWs with sorbent materials can enhance their potential to treat wastewater, particularly through enhancing the removal of N and P. This paper focuses on data from batch and mesocosm studies that were conducted to identify and assess sorbent materials suitable for use within CWs. The aim in using sorbent material was to enhance the combined removal of phosphate (PO4-P) and ammonium (NH4-N). The key selection criteria for the sorbent materials were that they possess effective PO4-P, NH4-N or combined pollutant removal, come from low cost and sustainable sources, have potential for reuse, for example as a fertiliser or soil conditioner, and show limited potential for re-release of adsorbed nutrients. The sorbent materials selected for testing were alum sludge from water treatment works, ochre derived from minewater treatment, biochar derived from various feedstocks, plasterboard and zeolite. The performance of the individual sorbents was assessed through

  8. Using of clay-salt slimes of 'Belaruskali' factory as a sorbents of radionuclide

    International Nuclear Information System (INIS)

    Maskalchuk, L.

    2010-01-01

    minimization of radioactive waste volume by concentration and condensation. The concept about differentiated collection of liquid radioactive waste opens ample opportunities for introduction sorption processes for direct purifying of waste right after their collection. Sorption method of purification of liquid radioactive waste would considerably facilitate further water-salt solution disposal after radionuclide extraction and would prevent further storage of concentrated liquid radioactive waste, formed at evaporation of initial liquid radioactive waste, would exclude necessity of expansion and service of short term storage of concentrated liquid radioactive waste, would eliminate the use of time-taking and expensive technologies for processing and concentration of liquid radioactive waste. The main task of sorption method application is choice and reception of selective sorbents. Application of the natural inorganic material with sorption properties attracts that in contrast to expensive synthetic sorbents it is widespread, accessible and have rather low cost price thanks to presence of the great storage in developed and studied deposits. The review of the scientific and technical data about structural and sorption properties of natural mineral shows, that the most perspective material for extraction of radionuclides of cesium and strontium, and also the most toxic transuranium elements, from liquid waste are aluminum silicates. By the preliminary researches realized in the JIPNR - Sosny of NAS of Belarus it is established, those clay-salt slimes are complex formations which basic components: potassium and sodium chlorides, dolomite, field spars, illite and quartz. The specific structure of clay-salt slimes causes: - Possibility of synthesis of wide scale materials of various special-purpose functions, - Updating of clay-salt slimes for reception of sorbents with set physical, chemical and sorption properties. It is shown that clay-salt slimes possess a considerable specific

  9. Development and thermochemical characterizations of vermiculite/SrBr_2 composite sorbents for low-temperature heat storage

    International Nuclear Information System (INIS)

    Zhang, Y.N.; Wang, R.Z.; Zhao, Y.J.; Li, T.X.; Riffat, S.B.; Wajid, N.M.

    2016-01-01

    Novel EVM/SrBr_2 composite sorbents with different salt contents were developed for low-temperature thermal energy storage (TES). Simulative sorption experiment was conducted to obtain the sorption kinetics diagram and identify threshold salt content that composite sorbents can hold without solution leakage. Distribution of salt embedded in EVM was observed by extreme-resolution scanning electron microscopy (ER-SEM). Thermochemical characterizations including desorption performance and desorption heat were fully investigated by analyzing simultaneous thermal analyzer (STA) results. Results reveal that sorption process of composite sorbents is divided into three parts: water adsorption of EVM, water adsorption of SrBr_2 crystal and liquid-gas absorption of SrBr_2 solution. Since SrBr_2 solution can be hold in macrospores of EVM, water uptake and energy storage density are greatly increased. It appears that the composite sorbent of EVMSrBr_240 is a promising material for thermal energy storage, with water uptake of 0.53 g/g, mass energy storage density of 0.46 kWh/kg and volume energy storage density of 105.36 kWh/m"3. - Highlights: • Vermiculite/SrBr_2 composite sorbents were developed for thermal energy storage. • Water uptake of composite sorbents is divided into three phases. • Energy storage density of each sorption phase is evaluated via calculations. • EVMSrBr_240 is chosen as optimal sorbent without solution leakage.

  10. Understanding factors affecting patient and public engagement and recruitment to digital health interventions: a systematic review of qualitative studies.

    Science.gov (United States)

    O'Connor, Siobhan; Hanlon, Peter; O'Donnell, Catherine A; Garcia, Sonia; Glanville, Julie; Mair, Frances S

    2016-09-15

    Numerous types of digital health interventions (DHIs) are available to patients and the public but many factors affect their ability to engage and enrol in them. This systematic review aims to identify and synthesise the qualitative literature on barriers and facilitators to engagement and recruitment to DHIs to inform future implementation efforts. PubMed, MEDLINE, CINAHL, Embase, Scopus and the ACM Digital Library were searched for English language qualitative studies from 2000 - 2015 that discussed factors affecting engagement and enrolment in a range of DHIs (e.g. 'telemedicine', 'mobile applications', 'personal health record', 'social networking'). Text mining and additional search strategies were used to identify 1,448 records. Two reviewers independently carried out paper screening, quality assessment, data extraction and analysis. Data was analysed using framework synthesis, informed by Normalization Process Theory, and Burden of Treatment Theory helped conceptualise the interpretation of results. Nineteen publications were included in the review. Four overarching themes that affect patient and public engagement and enrolment in DHIs emerged; 1) personal agency and motivation; 2) personal life and values; 3) the engagement and recruitment approach; and 4) the quality of the DHI. The review also summarises engagement and recruitment strategies used. A preliminary DIgital Health EnGagement MOdel (DIEGO) was developed to highlight the key processes involved. Existing knowledge gaps are identified and a number of recommendations made for future research. Study limitations include English language publications and exclusion of grey literature. This review summarises and highlights the complexity of digital health engagement and recruitment processes and outlines issues that need to be addressed before patients and the public commit to digital health and it can be implemented effectively. More work is needed to create successful engagement strategies and better

  11. Sulphation of calcium-based sorbents in circulating fluidised beds under oxy-fuel combustion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Francisco Garcia-Labiano; Luis F. de Diego; Alberto Abad; Pilar Gayan; Margarita de las Obras-Loscertales; Aranzazu Rufas; Juan Adanez [Instituto de Carboquimica (CSIC), Zaragoza (Spain). Dept. Energy and Environment

    2009-07-01

    Sulphur Retention (SR) by calcium-based sorbents is a process highly dependent on the temperature and CO{sub 2} concentration. In circulating fluidised beds combustors (CFBC's) operating under oxy-fuel conditions, the sulphation process takes place in atmospheres enriched in CO{sub 2} with bed concentrations that can vary from 40 to 95%. Under so high CO{sub 2} concentrations, very different from that in conventional coal combustion atmosphere with air, the calcination and sulphation behaviour of the sorbent must be defined to optimise the SR process in the combustor. The objective of this work was to determine the SO{sub 2} retention capacity of a Spanish limestone at typical oxy-fuel conditions in CFBC's. Long term duration tests of sulphation (up to 24 h), to simulate the residence time of sorbents in CFBC's, were carried out by thermogravimetric analysis (TGA). Clear behaviour differences were found under calcining and non-calcining conditions. Especially relevant was the result obtained at calcining conditions but close to the thermodynamic temperature given for sorbent calcination. This situation must be avoided in CFBC's because the CO{sub 2} produced inside the particle during calcination can destroy the particles if a non-porous sulphate product layer has been formed around the particle. The effect of the main variables on the sorbent sulphation such as SO{sub 2} concentration, temperature, and particle size were analysed in the long term TGA tests. These data were also used to determine the kinetic parameters for the sulphation under oxy-fuel combustion conditions, which were able to adequately predict the sulphation conversion values in a wide range of operating conditions. 20 refs., 5 figs., 2 tabs.

  12. Removal of metals from industrial wastewater and urban runoff by mineral and bio-based sorbents.

    Science.gov (United States)

    Gogoi, Harshita; Leiviskä, Tiina; Heiderscheidt, Elisangela; Postila, Heini; Tanskanen, Juha

    2018-03-01

    The study was performed to evaluate chemically modified biosorbents, hydrochloric acid treated peat (HCl-P) and citric acid treated sawdust (Citric acid-SD) for their metal removal capacity from dilute industrial wastewater and urban runoff and compare their efficiency with that of commercially available mineral sorbents (AQM PalPower M10 and AQM PalPower T5M5 magnetite). Batch and column experiments were conducted using real water samples to assess the sorbents' metal sorption capacity. AQM PalPower M10 (consisting mainly of magnesium, iron and silicon oxides) exhibited excellent Zn removal from both industrial wastewater and spiked runoff water samples even at low dosages (0.1 g/L and 0.05 g/L, respectively). The high degree of Zn removal was associated with the release of hydroxyl ions from the sorbent and subsequent precipitation of zinc hydroxide. The biosorbents removed Ni and Cr better than AQM PalPower M10 from industrial wastewater and performed well in removing Cr and Cu from spiked runoff water, although at higher dosages (0.3-0.75 g/L). The main mechanism of sorption by biosorbents was ion exchange. The sorbents required a short contact time to reach equilibrium (15-30 min) in both tested water samples. AQM PalPower T5M5 magnetite was the worst performing sorbent, leaching Zn into both industrial and runoff water and Ni into runoff water. Column tests revealed that both HCl-P and AQM PalPower M10 were able to remove metals, although some leaching was witnessed, especially As from AQM PalPower M10. The low hydraulic conductivity observed for HCl-P may restrict the possibilities of using such small particle size peat material in a filter-type passive system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. A Low Cost, High Capacity Regenerable Sorbent for Pre-combustion CO{sub 2} Capture

    Energy Technology Data Exchange (ETDEWEB)

    Alptekin, Gokhan

    2012-09-30

    The overall objective of the proposed research is to develop a low cost, high capacity CO{sub 2} sorbent and demonstrate its technical and economic viability for pre-combustion CO{sub 2} capture. The specific objectives supporting our research plan were to optimize the chemical structure and physical properties of the sorbent, scale-up its production using high throughput manufacturing equipment and bulk raw materials and then evaluate its performance, first in bench-scale experiments and then in slipstream tests using actual coal-derived synthesis gas. One of the objectives of the laboratory-scale evaluations was to demonstrate the life and durability of the sorbent for over 10,000 cycles and to assess the impact of contaminants (such as sulfur) on its performance. In the field tests, our objective was to demonstrate the operation of the sorbent using actual coal-derived synthesis gas streams generated by air-blown and oxygen-blown commercial and pilot-scale coal gasifiers (the CO{sub 2} partial pressure in these gas streams is significantly different, which directly impacts the operating conditions hence the performance of the sorbent). To support the field demonstration work, TDA collaborated with Phillips 66 and Southern Company to carry out two separate field tests using actual coal-derived synthesis gas at the Wabash River IGCC Power Plant in Terre Haute, IN and the National Carbon Capture Center (NCCC) in Wilsonville, AL. In collaboration with the University of California, Irvine (UCI), a detailed engineering and economic analysis for the new CO{sub 2} capture system was also proposed to be carried out using Aspen PlusTM simulation software, and estimate its effect on the plant efficiency.

  14. Phosphorus removal from aqueous solution using iron coated natural and engineered sorbents

    International Nuclear Information System (INIS)

    Boujelben, N.; Bouzid, J.; Elouear, Z.; Feki, M.; Jamoussi, F.; Montiel, A.

    2008-01-01

    New filtration materials covered with metallic oxides are good adsorbents for both cation and anion forms of pollutants. Sfax is one of the most important industrial towns in Tunisia. Its phosphate manufacture in particular is causing considerable amounts of water pollution. Therefore, there is a need to find out a new way of getting rid of this excessive phosphate from water. This work is aimed to examining the potential of three sorbent materials (synthetic iron oxide coated sand (SCS), naturally iron oxide coated sand (NCS) and iron oxide coated crushed brick (CB)) for removing phosphate ions from aqueous solutions. According to our literature survey CB was not used as adsorbent previously. Phosphate ions are used here as species model for the elimination of other similar pollutants (arsenates, antimonates). Optical microscope and scanning electron microscope (SEM) analyses were used to investigate the surface properties and morphology of the coated sorbents. Infra-red spectroscopy and X-ray diffraction techniques were also used to characterize the sorbent structures. Results showed that iron coated crushed brick possess more micro pores and a higher surface area owing to its clay nature. The comparative sorption of PO 4 3- from aqueous solutions by SCS, CB and NCS was investigated by batch experiments. The estimated optimum pH of phosphate ion retention for the considered sorbents was 5. The equilibrium data were analysed using the Langmuir and Freundlich isotherms. The sorption capacities of PO 4 3- at pH 5 were 1.5 mg/g for SCS, 1.8 mg/g for CB and 0.88 mg/g for NCS. The effect of temperature on sorption phenomenon was also investigated. The results indicated that adsorption is an endothermic process for phosphate ions removal. This study demonstrates that all the considered sorbents can be used as an alternative emerging technology for water treatment without any side effect or treatment process alteration

  15. Developing new understanding of photoelectrochemical water splitting via in-situ techniques: A review on recent progress

    Directory of Open Access Journals (Sweden)

    Jiajie Cen

    2017-04-01

    Full Text Available Photoelectrochemical (PEC water splitting is a promising technology for solar hydrogen production to build a sustainable, renewable and clean energy economy. Given the complexity of the PEC water splitting processes, it is important to note that developing in-situ techniques for studying PEC water splitting presents a formidable challenge. This review is aimed at highlighting advantages and disadvantages of each technique, while offering a pathway of potentially combining several techniques to address different aspects of interfacial processes in PEC water splitting. We reviewed recent progress in various techniques and approaches utilized to study PEC water splitting, focusing on spectroscopic and scanning-probe methods. Keywords: In-situ, Water splitting, IMPS, TAS, SPM

  16. Disseminating results to clinical trial participants: a qualitative review of patient understanding in a post-trial population.

    Science.gov (United States)

    Darbyshire, Julie Lorraine; Price, Hermione Clare

    2012-01-01

    To identify the most appropriate format for results dissemination to maximise understanding of trial results. Qualitative. Of the original 58 4-T trial centres, 34 agreed to take part in this ancillary research. All participants from these centres were eligible. All 343 participants were sent questionnaires. The low response rate meant that we were unable to make any firm conclusions about the patients' preferred method of dissemination; however, we were able to comment on the level of understanding demonstrated by the trial participants. All 40 (12%) returned questionnaires were received from 15 centres. We received no questionnaires from over half of the centres. The questionnaires which were returned demonstrated broad satisfaction with the results letter, general enthusiasm for the trial and a variable level of understanding of the results; however, there was a high proportion of responders who were not clear on why the research was undertaken or what the results meant. The low response rate may be related to delays during the trial set-up process suggesting that interest in a study quickly wanes for both patients and centres. From this we deduce that rapid dissemination of results is needed if it is to have any impact at all. The responders are likely to reflect a biased cohort who were both enthusiastic about the research and who had a good experience during their 3 years in the 4-T trial. It is perhaps not surprising therefore that the overview is positive. That this population was still not fully informed about the purpose of the research would seem to confirm a low level of understanding among the general public which we suggest should be addressed during the consent process.

  17. Understanding How Organized Youth Sport May Be Harming Individual Players within the Family Unit: A Literature Review

    Directory of Open Access Journals (Sweden)

    Corliss N. Bean

    2014-10-01

    Full Text Available Within the United States, close to 45 million youths between the ages of 6 and 18 participate in some form of organized sports. While recent reviews have shown the positive effects of youth sport participation on youth health, there are also several negative factors surrounding the youth sport environment. To date, a comprehensive review of the negative physical and psychological effects of organized sport on youth has not been done and little thus far has documented the effect organized sport has on other players within a family, particularly on parents and siblings. Therefore the purpose of this paper is to conduct a review of studies on the negative effects of organized sport on the youth athlete and their parents and siblings. Articles were found by searching multiple databases (Physical Education Index and Sociology, Psychology databases (Proquest, SPORTDiscus and Health, History, Management databases (EBSCOhost, Science, Social Science, Arts and Humanities on Web of Science (ISI, SCOPUS and Scirus (Elsevier. Results show the darker side of organized sport for actors within the family unit. A model is proposed to explain under which circumstances sport leads to positive versus negative outcomes, ideas for future research are drawn and recommendations are made to optimize the youth sport experience and family health.

  18. Understanding Bacterial Isolates in Blood Culture and Approaches Used to Define Bacteria as Contaminants: A Literature Review.

    Science.gov (United States)

    Hossain, Belal; Islam, Mohammad Shahidul; Rahman, Atiqur; Marzan, Mahfuza; Rafiqullah, Iftekhar; Connor, Nicholas E; Hasanuzzaman, Mohammad; Islam, Maksuda; Hamer, Davidson H; Hibberd, Patricia L; Saha, Samir K

    2016-05-01

    Interpretation of blood culture isolates is challenging due to a lack of standard methodologies for identifying contaminants. This problem becomes more complex when the specimens are from sick young infants, as a wide range of bacteria can cause illness among this group. We used 43 key words to find articles published between 1970 and 2011 on blood culture isolates and possible contaminants in the PubMed database. Experts were also consulted to obtain other relevant articles. Selection of articles followed systematic methods considering opinions from more than 1 reviewer. After reviewing the titles of 3869 articles extracted from the database, we found 307 relevant to our objective. Based on the abstracts, 42 articles were selected for the literature review. In addition, we included 7 more articles based on cross-references and expert advice. The most common methods for differentiating blood culture isolates were multiple blood cultures from the same subject, antibiograms and molecular testing. Streptococcus pneumoniae, Hemophilus influenzae, Neisseria meningitidis and group A and B streptococcus were always considered as pathogens, whereas Bacillus sp., Diphtheroids, Propionibacterium and Micrococcus were commonly regarded as contaminants. Coagulase-negative staphylococci were the most frequent isolates and usually reported as contaminants unless the patient had a specific condition, such as long-term hospitalization or use of invasive devices (catheters). Inaccurate interpretation of blood culture may falsely guide treatment and also has long-term policy implications. The combination of clinical and microbiological knowledge, patient's clinical history and laboratory findings are essential for appropriate interpretation of blood culture.

  19. Understanding How Organized Youth Sport May Be Harming Individual Players within the Family Unit: A Literature Review

    Science.gov (United States)

    Bean, Corliss N.; Fortier, Michelle; Post, Courtney; Chima, Karam

    2014-01-01

    Within the United States, close to 45 million youths between the ages of 6 and 18 participate in some form of organized sports. While recent reviews have shown the positive effects of youth sport participation on youth health, there are also several negative factors surrounding the youth sport environment. To date, a comprehensive review of the negative physical and psychological effects of organized sport on youth has not been done and little thus far has documented the effect organized sport has on other players within a family, particularly on parents and siblings. Therefore the purpose of this paper is to conduct a review of studies on the negative effects of organized sport on the youth athlete and their parents and siblings. Articles were found by searching multiple databases (Physical Education Index and Sociology, Psychology databases (Proquest), SPORTDiscus and Health, History, Management databases (EBSCOhost), Science, Social Science, Arts and Humanities on Web of Science (ISI), SCOPUS and Scirus (Elsevier). Results show the darker side of organized sport for actors within the family unit. A model is proposed to explain under which circumstances sport leads to positive versus negative outcomes, ideas for future research are drawn and recommendations are made to optimize the youth sport experience and family health. PMID:25275889

  20. A review and analysis of the use of 'habit' in understanding, predicting and influencing health-related behaviour.

    Science.gov (United States)

    Gardner, Benjamin

    2015-01-01

    The term 'habit' is widely used to predict and explain behaviour. This paper examines use of the term in the context of health-related behaviour, and explores how the concept might be made more useful. A narrative review is presented, drawing on a scoping review of 136 empirical studies and 8 literature reviews undertaken to document usage of the term 'habit', and methods to measure it. A coherent definition of 'habit', and proposals for improved methods for studying it, were derived from findings. Definitions of 'habit' have varied in ways that are often implicit and not coherently linked with an underlying theory. A definition is proposed whereby habit is a process by which a stimulus generates an impulse to act as a result of a learned stimulus-response association. Habit-generated impulses may compete or combine with impulses and inhibitions arising from other sources, including conscious decision-making, to influence responses, and need not generate behaviour. Most research on habit is based on correlational studies using self-report measures. Adopting a coherent definition of 'habit', and a wider range of paradigms, designs and measures to study it, may accelerate progress in habit theory and application.

  1. A review and analysis of the use of ‘habit’ in understanding, predicting and influencing health-related behaviour

    Science.gov (United States)

    Gardner, Benjamin

    2015-01-01

    The term ‘habit’ is widely used to predict and explain behaviour. This paper examines use of the term in the context of health-related behaviour, and explores how the concept might be made more useful. A narrative review is presented, drawing on a scoping review of 136 empirical studies and 8 literature reviews undertaken to document usage of the term ‘habit’, and methods to measure it. A coherent definition of ‘habit’, and proposals for improved methods for studying it, were derived from findings. Definitions of ‘habit’ have varied in ways that are often implicit and not coherently linked with an underlying theory. A definition is proposed whereby habit is a process by which a stimulus generates an impulse to act as a result of a learned stimulus-response association. Habit-generated impulses may compete or combine with impulses and inhibitions arising from other sources, including conscious decision-making, to influence responses, and need not generate behaviour. Most research on habit is based on correlational studies using self-report measures. Adopting a coherent definition of ‘habit’, and a wider range of paradigms, designs and measures to study it, may accelerate progress in habit theory and application. PMID:25207647

  2. Sorbent Injection for Small ESP Mercury Control in Low Sulfur Eastern Bituminous Coal Flue Gas

    Energy Technology Data Exchange (ETDEWEB)

    Carl Richardson; Katherine Dombrowski; Douglas Orr

    2006-12-31

    This project Final Report is submitted to the U.S. Department of Energy (DOE) as part of Cooperative Agreement DE-FC26-03NT41987, 'Sorbent Injection for Small ESP Mercury Control in Low Sulfur Eastern Bituminous Coal Flue Gas.' Sorbent injection technology is targeted as the primary mercury control process on plants burning low/medium sulfur bituminous coals equipped with ESP and ESP/FGD systems. About 70% of the ESPs used in the utility industry have SCAs less than 300 ft2/1000 acfm. Prior to this test program, previous sorbent injection tests had focused on large-SCA ESPs. This DOE-NETL program was designed to generate data to evaluate the performance and economic feasibility of sorbent injection for mercury control at power plants that fire bituminous coal and are configured with small-sized electrostatic precipitators and/or an ESP-flue gas desulfurization (FGD) configuration. EPRI and Southern Company were co-funders for the test program. Southern Company and Reliant Energy provided host sites for testing and technical input to the project. URS Group was the prime contractor to NETL. ADA-ES and Apogee Scientific Inc. were sub-contractors to URS and was responsible for all aspects of the sorbent injection systems design, installation and operation at the different host sites. Full-scale sorbent injection for mercury control was evaluated at three sites: Georgia Power's Plant Yates Units 1 and 2 [Georgia Power is a subsidiary of the Southern Company] and Reliant Energy's Shawville Unit 3. Georgia Power's Plant Yates Unit 1 has an existing small-SCA cold-side ESP followed by a Chiyoda CT-121 wet scrubber. Yates Unit 2 is also equipped with a small-SCA ESP and a dual flue gas conditioning system. Unit 2 has no SO2 control system. Shawville Unit 3 is equipped with two small-SCA cold-side ESPs operated in series. All ESP systems tested in this program had SCAs less than 250 ft2/1000 acfm. Short-term parametric tests were conducted on Yates

  3. Waste treatment and immobilization technologies involving inorganic sorbents. Final report of a co-ordinated research programme 1992-1996

    International Nuclear Information System (INIS)

    1997-06-01

    A Coordinated Research Programme (CRP) for the application of inorganic sorbents in liquid waste treatment and immobilization was initiated by the IAEA in 1992. The results of this CRP are presented in this report. Fifteen institutions from fourteen countries were involved in this programme. The framework of this CRP was: (1) to conduct fundamental studies on sorbent structure and sorption mechanism; (2) to obtain thermodynamic and kinetic data of the treatment process; (3) to define sorption mechanism of radionuclides on different soils; (4) to identify sorbents appropriate for treatment of liquid waste streams; (5) to develop standard tests to be able to compare results of different groups of investigations. Refs, figs, tabs

  4. Using fuzzy-trace theory to understand and improve health judgments, decisions, and behaviors: A literature review.

    Science.gov (United States)

    Blalock, Susan J; Reyna, Valerie F

    2016-08-01

    Fuzzy-trace theory is a dual-process model of memory, reasoning, judgment, and decision making that contrasts with traditional expectancy-value approaches. We review the literature applying fuzzy-trace theory to health with 3 aims: evaluating whether the theory's basic distinctions have been validated empirically in the domain of health; determining whether these distinctions are useful in assessing, explaining, and predicting health-related psychological processes; and determining whether the theory can be used to improve health judgments, decisions, or behaviors, especially compared to other approaches. We conducted a literature review using PubMed, PsycINFO, and Web of Science to identify empirical peer-reviewed papers that applied fuzzy-trace theory, or central constructs of the theory, to investigate health judgments, decisions, or behaviors. Seventy nine studies (updated total is 94 studies; see Supplemental materials) were identified, over half published since 2012, spanning a wide variety of conditions and populations. Study findings supported the prediction that verbatim and gist representations are distinct constructs that can be retrieved independently using different cues. Although gist-based reasoning was usually associated with improved judgment and decision making, 4 sources of bias that can impair gist reasoning were identified. Finally, promising findings were reported from intervention studies that used fuzzy-trace theory to improve decision making and decrease unhealthy risk taking. Despite large gaps in the literature, most studies supported all 3 aims. By focusing on basic psychological processes that underlie judgment and decision making, fuzzy-trace theory provides insights into how individuals make decisions involving health risks and suggests innovative intervention approaches to improve health outcomes. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  5. Understanding Eating Behavior during the Transition from Adolescence to Young Adulthood: A Literature Review and Perspective on Future Research Directions

    Directory of Open Access Journals (Sweden)

    F. Marijn Stok

    2018-05-01

    Full Text Available Introduction: Eating behavior often becomes unhealthier during the transition from adolescence to young adulthood, but not much is known about the factors that drive this change. We assess the available evidence on this topic through a literature review and pay special attention to the research designs employed in the studies available as well as the modifiability of the factors investigated in previous research. Method: We systematically conducted a scoping review by searching literature published in or after 2000 in three databases that described one or more factors associated with eating behavior or changes in eating behavior during the transition from adolescence to adulthood in the general population. Our search identified eighteen articles meeting these inclusion criteria. The socio-ecological DONE (Determinants of Nutrition and Eating framework, a recently developed dynamic framework of factors shaping dietary behavior, was used to structure and categorize the factors identified. Results: Most factors identified in the literature were individual-level factors (67% such as food beliefs, time constraints, and taste preferences; on the other hand, interpersonal-level factors (e.g., social support, environmental-level factors (e.g., product characteristics and policy-level factors (e.g., market regulations have been reported on less extensively. Furthermore, most factors discussed in the literature have been classified in the DONE framework as not easily modifiable. Moreover, previous studies largely used static research designs and focused primarily on one specific population (US freshmen. Discussion: This systematic scoping review identified several gaps in the available literature that hinder insight into the drivers of eating behavior (change during the transition from adolescence to young adulthood. There is an urgent need for research on broader populations, employing dynamic repeated-measures designs, and taking modifiability of

  6. Understanding patients’ decision-making strategies in hospital choice: Literature review and a call for experimental research

    Directory of Open Access Journals (Sweden)

    Sophia Fischer

    2015-12-01

    Full Text Available Insights from psychology and cognitive science have, as yet, barely entered hospital choice research. This conceptual article closes this gap by reviewing and conceptually framing the current literature on hospital choice and patient information behavior and by discussing which tools are needed to advance scientific methodology in the study of patient decision-making strategies in hospital choice. Specifically, we make a call for more experimental research in hospital choice in order to complement existing theories, methods, and tools. This article introduces computerized process-tracing tools in hospital choice research, and also outlines a hands-on example, to provide a basis for future research.

  7. Feedbacks between geomorphology and biota controlling Earth surface processes and landforms: A review of foundation concepts and current understandings

    Science.gov (United States)

    Corenblit, Dov; Baas, Andreas C. W.; Bornette, Gudrun; Darrozes, José; Delmotte, Sébastien; Francis, Robert A.; Gurnell, Angela M.; Julien, Frédéric; Naiman, Robert J.; Steiger, Johannes

    2011-06-01

    This review article presents recent advances in the field of biogeomorphology related to the reciprocal coupling between Earth surface processes and landforms, and ecological and evolutionary processes. The aim is to present to the Earth Science community ecological and evolutionary concepts and associated recent conceptual developments for linking geomorphology and biota. The novelty of the proposed perspective is that (1) in the presence of geomorphologic-engineer species, which modify sediment and landform dynamics, natural selection operating at the scale of organisms may have consequences for the physical components of ecosystems, and particularly Earth surface processes and landforms; and (2) in return, these modifications of geomorphologic processes and landforms often feed back to the ecological characteristics of the ecosystem (structure and function) and thus to biological characteristics of engineer species and/or other species (adaptation and speciation). The main foundation concepts from ecology and evolutionary biology which have led only recently to an improved conception of landform dynamics in geomorphology are reviewed and discussed. The biogeomorphologic macroevolutionary insights proposed explicitly integrate geomorphologic niche-dimensions and processes within an ecosystem framework and reflect current theories of eco-evolutionary and ecological processes. Collectively, these lead to the definition of an integrated model describing the overall functioning of biogeomorphologic systems over ecological and evolutionary timescales.

  8. A review of human factors challenges of complex adaptive systems: discovering and understanding chaos in human performance.

    Science.gov (United States)

    Karwowski, Waldemar

    2012-12-01

    In this paper, the author explores a need for a greater understanding of the true nature of human-system interactions from the perspective of the theory of complex adaptive systems, including the essence of complexity, emergent properties of system behavior, nonlinear systems dynamics, and deterministic chaos. Human performance, more often than not, constitutes complex adaptive phenomena with emergent properties that exhibit nonlinear dynamical (chaotic) behaviors. The complexity challenges in the design and management of contemporary work systems, including service systems, are explored. Examples of selected applications of the concepts of nonlinear dynamics to the study of human physical performance are provided. Understanding and applications of the concepts of theory of complex adaptive and dynamical systems should significantly improve the effectiveness of human-centered design efforts of a large system of systems. Performance of many contemporary work systems and environments may be sensitive to the initial conditions and may exhibit dynamic nonlinear properties and chaotic system behaviors. Human-centered design of emergent human-system interactions requires application of the theories of nonlinear dynamics and complex adaptive system. The success of future human-systems integration efforts requires the fusion of paradigms, knowledge, design principles, and methodologies of human factors and ergonomics with those of the science of complex adaptive systems as well as modern systems engineering.

  9. A Review on Experimental Measurements for Understanding Efficiency Droop in InGaN-Based Light-Emitting Diodes

    Directory of Open Access Journals (Sweden)

    Lai Wang

    2017-10-01

    Full Text Available Efficiency droop in GaN-based light emitting diodes (LEDs under high injection current density perplexes the development of high-power solid-state lighting. Although the relevant study has lasted for about 10 years, its mechanism is still not thoroughly clear, and consequently its solution is also unsatisfactory up to now. Some emerging applications, e.g., high-speed visible light communication, requiring LED working under extremely high current density, makes the influence of efficiency droop become more serious. This paper reviews the experimental measurements on LED to explain the origins of droop in recent years, especially some new results reported after 2013. Particularly, the carrier lifetime of LED is analyzed intensively and its effects on LED droop behaviors are uncovered. Finally, possible solutions to overcome LED droop are discussed.

  10. Review on influences of colloids on geologic disposal of high level radioactive waste. For better understanding of natural colloidal materials

    International Nuclear Information System (INIS)

    Kanai, Yutaka; Suzuki, Masaya; Kamioka, Hikari; Yoshida, Takahiro; Suko, Takeshi

    2007-01-01

    Although the influences of colloidal materials on radionuclide transport in geological media are pointed out, their behaviors in natural environment have not yet been well elucidated and therefore their influences on the geologic disposal of high-level radioactive waste (HLW) are not fully estimated quantitatively. This paper reviewed the studies on natural colloids, especially focused on inorganic, organic and biological colloids, and discussed the future works to be carried out. Much attention should be paid to the sampling and analysis. Excellent techniques for in-situ observation, concentration without changing the state of colloid, standard procedure for analysis, are necessary to be developed. More research studies on the behaviors of colloids are required in not only far- and near-fields but also items on effects of the environments and its evolution. (author)

  11. Epidemiology of competence: a scoping review to understand the risks and supports to competence of four health professions

    Science.gov (United States)

    Glover Takahashi, Susan; Nayer, Marla

    2017-01-01

    Objectives This study examined the risks and supports to competence discussed in the literature related to occupational therapists, pharmacists, physical therapists and physicians, using epidemiology as a conceptual model. Design Articles from a scoping literature review, published from 1975 to 2014 inclusive, were included if they were about a risk or support to the professional or clinical competence of one of four health professions. Descriptive and regression analyses identified potential associations between risks and supports to competence and the location of study, type of health profession, competence life-cycle and the domain(s) of competence (organised around the CanMEDS framework). Results A total of 3572 abstracts were reviewed and 943 articles analysed. Most focused on physicians (n=810, 86.0%) and ‘practice’ (n=642, 68.0%). Fewer articles discussed risks to competence (n=418, 44.3%) than supports (n=750, 79.5%). The top four risks, each discussed in over 15% of articles, were: transitions in practice, being an international graduate, lack of clinical exposure/experience (ie, insufficient volume of procedures or patients) and age. The top two supports (over 35%) were continuing education participation and educational information/programme features. About 60% of all the articles discussed medical expert and about 25% applied to all roles. Articles focusing on residents had a greater probability of reporting on risks. Conclusions Articles about physicians were dominant. The majority of articles were written in the last decade and more discussed supports than risks to competence. An epidemiology-based conceptual model offers a helpful organising framework for exploring and explaining the competence of health professions. PMID:28864686

  12. The cleaning of the soils polluted by oil and radionuclides by natural sorbents

    International Nuclear Information System (INIS)

    Farajov, M.F.; Shamilov, E.N.; Abdullayev, A.S.; Huseynov, V.I.

    2005-01-01

    Full text : Problem of environmental pollution in oil extracting areas of Absheron peninsula became the very important discussion object lately. It this areas for many years oil and well waters were flowed to environmental areas caused a lot of pools in that areas and at the result the soil and plants were polluted with oil and radionuclides. By last years researches it was revealed that amount of radium 226 oil well water contains 10 - 500 Bq/l. Sometimes amount of radium 226 in polluted soils is increasing to 2000--5000 Bq/l and at the result it is raising probability of entering radionuclides by the way of migration from ground to plants into the nutrition chain cycle. Thus the polluted areas with oil and radionuclides and also when oil spills from oil-pipes by an accident the deactivation of soils is one of the main and most actual problems. In researches for cleaning of polluted soils with radionuclides for the first time were used the phyto sorbent modified breccias forms taken from Chaildag, Gobu, and Lokbatan mud volcano areas. The mineral contain of volcano mud generally consists of clay rocks -(kaolinit, montmorillonit, zeolite, chlorite, biotit) pyrite, and i.e.[2]. The polluted soil samples were taken in Surakhani region from area with the 150 mikroroentgen per hour radiation background. The contain and amount of radionuclides were determined with the radio spectrometer P rogress - Beta - Gamma . Polluted soil samples firstly are washed by hot water and HCl solution by mixing for 3-5 hours. At the next level by adding pieced sorbent into the solution is intensively mixing by mixer and putting for sedimentation for 24 hours. After sedimentation the stiring process is repeated by adding HCl on the sediment again. The soil is stirred by water for last time. Decomposed solutions from soil are adhering and are maked with sorbent again. Thus the soil is quite cleaned from oil and radionuclides by the sorbents we offer. At the same time this sorbents may be

  13. Extraction of trace nitrophenols in environmental water samples using boronate affinity sorbent

    International Nuclear Information System (INIS)

    Zhang, Yong; Mei, Meng; Huang, Xiaojia; Yuan, Dongxing

    2015-01-01

    In this research, the applicability of a new sorbent based on boronate affinity material is demonstrated. For this purpose, six strong polar nitrophenols were selected as models which are difficult to be extracted in neutral form (only based on hydrophobic interactions). The extracted nitrophenols were separated and determined by high-performance liquid chromatography with diode array detection. The sorbent was synthesized by in situ copolymerization of 3-acrylamidophenylboronic acid and divinylbenzene using dimethyl sulfoxide and azobisisobutyronitrile as porogen solvent and initiator, respectively. The effect of the preparation parameters in the polymerization mixture on extraction performance was investigated in detail. The size and morphology of the sorbent have been characterized via different techniques such as infrared spectroscopy, elemental analysis, scanning electron microscopy and mercury intrusion porosimetry. The important parameters influencing the extraction efficiency were studied and optimized thoroughly. Under the optimum extraction conditions, the limits of detection (S/N = 3) and limits of quantification (S/N = 10) for the target nitrophenols were 0.097–0.28 and 0.32–0.92 μg/L, respectively. The precision of the proposed method was evaluated in terms of intra- and inter-assay variability calculated as RSD, and it was found that the RSDs were all below 9%. Finally, the developed method was successfully applied for environmental water samples such as wastewater, tap, lake and river water. The recoveries varied within the range of 71.2–115% with RSD below 11% in all cases. The results well demonstrate that the new boronate affinity sorbent can extract nitrophenols effectively through multi-interactions including boron–nitrogen coordination, hydrogen-bond and hydrophobic interactions between sorbent and analytes. - Highlights: • A new boronate affinity sorbent (BAS) was prepared. • The BAS was used as the extractive medium of stir

  14. Understanding and Measuring LGBTQ Pathways to Health: A Scoping Review of Strengths-Based Health Promotion Approaches in LGBTQ Health Research.

    Science.gov (United States)

    Gahagan, Jacqueline; Colpitts, Emily

    2017-01-01

    Health research traditionally has focused on the health risks and deficits of lesbian, gay, bisexual, transgender, and queer (LGBTQ) populations, obscuring the determinants that can promote health across the life course. Recognizing, appropriately measuring, and rendering visible these determinants of health is paramount to informing appropriate and engaging health policies, services, and systems for LGBTQ populations. The overarching purpose of this article is to provide an overview of the findings of a scoping review aimed at exploring strengths-based health promotion approaches to understanding and measuring LGBTQ health. Specifically, this scoping review examined peer-reviewed, published academic literature to determine (a) existing methodological frameworks for studying LGBTQ health from a strengths-based health promotion approach, and (b) suggestions for future methodological approaches for studying LGBTQ health from a strengths-based health promotion approach. The findings of this scoping review will be used to inform the development of a study aimed at assessing the health of and improving pathways to health services among LGBTQ populations in Nova Scotia, Canada.

  15. Sulfation diffusion model for SO{sub 2} capture on the T-T sorbent at moderate temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y.R.; Yang, L.Z.; You, C.F.; Qi, H.Y. [Tsinghua University, Beijing (China)

    2009-07-15

    A sulfation model was developed for dry flue gas desulfurization (FGD) at moderate temperatures to describe the reaction characteristics of the T-T sorbent clusters and the fine CaO particles that fall off the sorbent grains in a circulating fluidized bed (CFB) reactor. The cluster model describes the calcium conversion and reaction rate for various size sorbent clusters. The sulfation reaction is first order with respect to the SO{sub 2} concentration above 973 K. The calcium conversion and reaction rate for the CaO particles were obtained by extrapolation. In the model for CaO particle, the reaction rate is linearly related to the calcium conversion and the SO{sub 2} concentration in the rapid reaction stage and linearly related only with the calcium conversion after the product layer forms. The sulfation model accurately describes the sulfation of the T-T sorbent flowing through a CFB reactor.

  16. Preparation and investigation of ion exchange properties of sorbent based on activated carbon BAU and zirconium hydroxide

    International Nuclear Information System (INIS)

    Blokhin, A.A.; Semenov, M.I.; Taushkanov, V.P.; Andronov, E.A.

    1978-01-01

    The method of obtaining the sorbent based on the activated carbon and zirconium hydroxide, performed by carbon soaking by zirconium salt solution, hydrolytic decomposition, being in salt pores by ammonia solution and drying of the obtained sorbet in the air at the temperature of 105-115 deg. The kinetic characteristics of the obtained sorbent in the wide range of pH value of solutions are studied; sodium, chloride, fluoride and phosphate ion sorbtion taken as examples. A high selectivity of the sorbent to phosphate and fluoride ions has been established. The usefullness of the obtained sorbent for extraction of phosphorus microquantities from 1M sodium chloride solution and its concentration at the elution stage is shown

  17. Thermodynamics of organic molecule adsorption on sorbents modified with 5-hydroxy-6-methyluracil by inverse gas chromatography.

    Science.gov (United States)

    Gus'kov, Vladimir Yu; Gainullina, Yulia Yu; Ivanov, Sergey P; Kudasheva, Florida Kh

    2014-08-22

    The thermodynamic features of organic molecule adsorption from the gaseous phase of sorbents modified with 5-hydroxy-6-methyluracil (HMU) were studied. Molar internal energy and entropy of adsorption variation analyses showed that with every type surface, except for silica gel, layers of supramolecular structure have cavities equal in size with the ones revealed in HMU crystals by X-ray diffraction. Adsorption thermodynamics on HMU-modified sorbents depended on the amount of impregnated HMU and on the polarity, but not the porosity, of the initial sorbent. Polarity of the modified surface increased as a function of HMU quantity and initial sorbent mean pore size, but become appreciably lower if the initial surface is capable of hydrogen bonding. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Diatomaceous earth and activated bauxite used as granular sorbents for the removal of sodium chloride vapor from hot flue gas

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.H.D.; Swift, W.M.; Johnson, I.

    1980-01-01

    Diatomaceous earth and activated bauxite were tested as granular sorbents for use as filter media in granular-bed filters for the removal of gaseous alkali metal compounds from the hot (800/sup 0/C) flue gas of PFBC. Tests were performed at atmospheric pressure, using NaCl vapor transported in relatively dry simulated flue gas of PFBC. Either a fixed-bed combustor or a high-temperature sorption test rig was used. The effects of sorbent bed temperature, superficial gas velocity, gas hourly space velocity, and NaCl-vapor concentration in flue gas on the sorption behavior of these two sorbents and their ultimate sorption capacities were determined. Both diatomaceous earth and activated bauxite were found to be very effective in removing NaCl vapor from flue gas. Preliminary cost evaluations showed that they are economically attractive as granular sorbents for cleaning alkali vapor from simulated flue gas.

  19. Effect of precursor and preparation method on manganese based activated carbon sorbents for removing H2S from hot coal gas.

    Science.gov (United States)

    Wang, Jiancheng; Qiu, Biao; Han, Lina; Feng, Gang; Hu, Yongfeng; Chang, Liping; Bao, Weiren

    2012-04-30

    Activated carbon (AC) supported manganese oxide sorbents were prepared by the supercritical water impregnation (SCWI) using two different precursor of Mn(NO(3))(2) (SCW(N)) and Mn(Ac)(2)·4H(2)O (SCW(A)). Their capacities of removing H(2)S from coal gas were evaluated and compared to the sorbents prepared by the pore volume impregnation (PVI) method. The structure and composition of different sorbents were characterized by XRD, SEM, TEM, XPS and XANES techniques. It is found that the precursor of active component plays the crucial role and SCW(N) sorbents show much better sulfidation performance than the SCW(A) sorbents. This is because the Mn(3)O(4) active phase of the SCW(N) sorbents are well dispersed on the AC support, while the Mn(2)SiO(4)-like species in the SCW(A) sorbent can be formed and seriously aggregated. The SCW(N) sorbents with 2.80% and 5.60% manganese are favorable for the sulfidation reaction, since the Mn species are better dispersed on the SCW(N) sorbents than those on the PV(N) sorbents and results in the better sulfidation performance of the SCW(N) sorbents. As the Mn content increases to 11.20%, the metal oxide particles on AC supports aggregate seriously, which leads to poorer sulfidation performance of the SCW(N)11.20% sorbents than that of the PV(N)11.20% sorbents. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Analyzing high resolution topography for advancing the understanding of mass and energy transfer through landscapes: A review

    Science.gov (United States)

    Passaiacquaa, Paola; Belmont, Patrick; Staley, Dennis M.; Simley, Jeffery; Arrowsmith, J. Ramon; Bode, Collin A.; Crosby, Christopher; DeLong, Stephen; Glenn, Nancy; Kelly, Sara; Lague, Dimitri; Sangireddy, Harish; Schaffrath, Keelin; Tarboton, David; Wasklewicz, Thad; Wheaton, Joseph

    2015-01-01

    The study of mass and energy transfer across landscapes has recently evolved to comprehensive considerations acknowledging the role of biota and humans as geomorphic agents, as well as the importance of small-scale landscape features. A contributing and supporting factor to this evolution is the emergence over the last two decades of technologies able to acquire high resolution topography (HRT) (meter and sub-meter resolution) data. Landscape features can now be captured at an appropriately fine spatial resolution at which surface processes operate; this has revolutionized the way we study Earth-surface processes. The wealth of information contained in HRT also presents considerable challenges. For example, selection of the most appropriate type of HRT data for a given application is not trivial. No definitive approach exists for identifying and filtering erroneous or unwanted data, yet inappropriate filtering can create artifacts or eliminate/distort critical features. Estimates of errors and uncertainty are often poorly defined and typically fail to represent the spatial heterogeneity of the dataset, which may introduce bias or error for many analyses. For ease of use, gridded products are typically preferred rather than the more information-rich point cloud representations. Thus many users take advantage of only a fraction of the available data, which has furthermore been subjected to a series of operations often not known or investigated by the user. Lastly, standard HRT analysis work-flows are yet to be established for many popular HRT operations, which has contributed to the limited use of point cloud data.In this review, we identify key research questions relevant to the Earth-surface processes community within the theme of mass and energy transfer across landscapes and offer guidance on how to identify the most appropriate topographic data type for the analysis of interest. We describe the operations commonly performed from raw data to raster products and

  1. Understanding factors that influence participation in physical activity among people with a neuromusculoskeletal condition: a review of qualitative studies.

    Science.gov (United States)

    Newitt, Rosemarie; Barnett, Fiona; Crowe, Melissa

    2016-01-01

    This review aims to describe the factors that influence participation in physical activity (PA) in people with neuromusculoskeletal (NMS) conditions. A systematic search of six databases was conducted. Articles were included if the study qualitatively explored factors that influence participation in PA by individuals with a NMS condition. Fifteen peer-reviewed articles published between 2003 and 2013 were analysed for common themes and critically appraised. Results were categorised using the International Classification of Functioning, Disability and Health framework. The most common demotivators reported for the three areas of functioning, body function and structures, activities and participation were lack of walking balance, muscle weakness, pain, stiffness, bladder and blower problems, depression, thermoregulation and fear of injury. Fluctuating symptoms and fatigue were mentioned as demotivators in all of the progressive conditions. Maintaining independence, function and weight, and the prevention of secondary conditions were the leading motivators reported in this domain. Most common environmental barriers include accessibility, costs, transport and insufficient information and knowledge from health professionals. Social support is a consistent determinate of PA and is reported as a facilitator in every study. The most common personal demotivators include lack of motivation, feelings of self-consciousness and embarrassment in public, anxiety, frustration and anger. Personal motivators include goal setting and achieving, enjoyment, feeling good, feeling "normal", motivation and optimism, redefining self and escapism from everyday boundaries. Individuals with NMS conditions report complex common barriers, facilitators, demotivators and motivators to participation in PA. The way these factors influence participation in PA is unique to the individual; therefore, it is necessary to adopt an individually tailored approach when designing interventions. Individuals

  2. Feasibility Study for the Use of Green, Bio-Based, Efficient Reactive Sorbent Material to Neutralize Chemical Warfare Agents

    Science.gov (United States)

    2012-08-02

    REPORT Feasibility study for the use of green, bio-based, efficient reactive sorbent material to neutralize chemical warfare agents 14. ABSTRACT 16...way cellulose, lignin and hemicelluloses interact as well as whole wood dissolution occurs in ILs. The present project was conducted to 1. REPORT...Feasibility study for the use of green, bio-based, efficient reactive sorbent material to neutralize chemical warfare agents Report Title ABSTRACT Over the

  3. Understanding Atmospheric Behaviour in Terms of Entropy: A Review of Applications of the Second Law of Thermodynamics to Meteorology

    Directory of Open Access Journals (Sweden)

    Donghai Wang

    2011-01-01

    Full Text Available The concept of entropy and its relevant principles, mainly the principle of maximum entropy production (MEP, the effect of negative entropy flow (NEF on the organization of atmospheric systems and the principle of the Second Law of thermodynamics, as well as their applications to atmospheric sciences, are reviewed. Some formulations of sub-grid processes such as diffusion parameterization schemes in computational geophysical fluid dynamics that can be improved based on full-irreversibility are also discussed, although they have not yet been systematically subjected to scrutiny from the perspective of the entropy budgets. A comparative investigation shows that the principle of MEP applies to the entropy production of macroscopic fluxes and determines the most probable state, that is, a system may choose a development meta-stable trajectory with a smaller production since entropy production behavior involves many specific dynamical and thermodynamic processes in the atmosphere and the extremal principles only provide a general insight into the overall configuration of the atmosphere. In contrast to the principle of MEP, the analysis of NEF is able to provide a new insight into the mechanism responsible for the evolution of a weather system as well as a new approach to predicting its track and intensity trend.

  4. Understanding Effective Delivery of Patient and Family Education in Pediatric Oncology: A Systematic Review from the Children's Oncology Group

    Science.gov (United States)

    Rodgers, Cheryl C.; Laing, Catherine M.; Herring, Ruth Anne; Tena, Nancy; Leonardelli, Adrianne; Hockenberry, Marilyn; Hendricks-Ferguson, Verna

    2016-01-01

    A diagnosis of childhood cancer is a life-changing event for the entire family. Parents must not only deal with the cancer diagnosis but also acquire new knowledge and skills to safely care for their child at home. Best practices for delivery of patient/family education after a new diagnosis of childhood cancer are currently unknown. The purpose of this systematic review was to evaluate the existing body of evidence to determine the current state of knowledge regarding the delivery of education to newly diagnosed pediatric oncology patients and families. Eighty-three articles regarding educational methods, content, influencing factors, and interventions for newly diagnosed pediatric patients with cancer or other chronic illnesses were systematically identified, summarized, and appraised according to the GRADE criteria. Based on the evidence, ten recommendations for practice were identified. These recommendations address delivery methods, content, influencing factors, and educational interventions for parents and siblings. Transferring these recommendations into practice may enhance the quality of education delivered by healthcare providers, and received by patients and families following a new diagnosis of childhood cancer. PMID:27450361

  5. A short review of our current understanding of the development of ring faults during collapse caldera formation

    Directory of Open Access Journals (Sweden)

    Adelina eGeyer

    2014-09-01

    Full Text Available The term collapse caldera refers to those volcanic depressions resulting from the sinking of the chamber roof due to the rapid withdrawal of magma during the course of an eruption. During the last three decades, collapse caldera dynamics has been the focus of attention of numerous, theoretical, numerical and experimental studies. Nonetheless, even if there is a tendency to go for a general and comprehensive caldera dynamics model, some key aspects remain unclear, controversial or completely unsolved. This is the case of ring fault nucleation points and propagation and dip direction. Since direct information on calderas’ deeper structure comes mainly from partially eroded calderas or few witnessed collapses, ring faults layout at depth remains still uncertain. This has generated a strong debate over the detailed internal fault and fracture configuration of a caldera collapse and, in more detail, how ring faults initiate and propagate. We offer here a very short description of the main results obtained by those analogue and theoretical/mathematical models applied to the study of collapse caldera formation. We place special attention on those observations related to the nucleation and propagation of the collapse-controlling ring faults. This summary is relevant to understand the current state-of-the-art of this topic and it should be taken under consideration in future works dealing with collapse caldera dynamics.

  6. Understanding the experience of initiating community-based physical activity and social support by people with serious mental illness: a systematic review using a meta-ethnographic approach

    Directory of Open Access Journals (Sweden)

    Helen Quirk

    2017-10-01

    Full Text Available Abstract Background People with long-term serious mental illness live with severe and debilitating symptoms that can negatively influence their health and quality of life, leading to outcomes such as premature mortality, morbidity and obesity. An interplay of social, behavioural, biological and psychological factors is likely to contribute to their poor physical health. Participating in regular physical activity could bring symptomatic improvements, weight loss benefits, enhanced wellbeing and when undertaken in a community-based group setting can yield additional, important social support benefits. Yet poor uptake of physical activity by people with serious mental illness is a problem. This review will systematically search, appraise and synthesise the existing evidence that has explored the experience of community-based physical activity initiation and key features of social support within these contexts by adults with schizophrenia, bipolar affective disorder, major depressive disorder or psychosis using the meta-ethnography approach. This new understanding may be key in designing more acceptable and effective community-based group PA programmes that meet patients’ need and expectations. Methods This will be a systematic review of qualitative studies using the meta-ethnography approach. The following databases will be searched: ASSIA, CINAHL, Cochrane Central Register of Controlled Trials, EMBASE, Health Technology Assessment Database, MEDLINE, PsycINFO, Sociological Abstracts, SPORTDiscus and Web of Science. Grey literature will also be sought. Eligible studies will use qualitative methodology; involve adults (≥18 years with schizophrenia, bipolar affective disorder, major depressive disorder or psychosis; will report community-based group physical activity; and capture the experience of physical activity initiation and key features of social support from the perspective of the participant. Study selection and assessment of quality will

  7. Effect of cerium oxide doping on the performance of CaO-based sorbents during calcium looping cycles.

    Science.gov (United States)

    Wang, Shengping; Fan, Shasha; Fan, Lijing; Zhao, Yujun; Ma, Xinbin

    2015-04-21

    A series of CaO-based sorbents were synthesized through a sol-gel method and doped with different amounts of CeO2. The sorbent with a Ca/Ce molar ratio of 15:1 showed an excellent absorption capacity (0.59 gCO2/g sorbent) and a remarkable cycle durability (up to 18 cycles). The admirable capture performance of CaCe-15 was ascribed to its special morphology formed by the doping of CeO2 and the well-distributed CeO2 particles. The sorbents doped with CeO2 possessed a loose shell-connected cross-linking structure, which was beneficial for the contact between CaO and CO2. CaO and CeO2 were dispersed homogeneously, and the existence of CeO2 also decreased the grain size of CaO. The well-dispersed CeO2, which could act as a barrier, effectively prevented the CaO crystallite from growing and sintering, thus the sorbent exhibited outstanding stability. The doping of CeO2 also improved the carbonation rate of the sorbent, resulting in a high capacity in a short period of time.

  8. EVALUATION OF SOLID SORBENTS AS A RETROFIT TECHNOLOGY FOR CO2 CAPTURE FROM COAL-FIRED POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Holly Krutka; Sharon Sjostrom

    2011-07-31

    Through a U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) funded cooperative agreement DE-NT0005649, ADA Environmental Solutions (ADA) has begun evaluating the use of solid sorbents for CO{sub 2} capture. The project objective was to address the viability and accelerate development of a solid-based CO{sub 2} capture technology. To meet this objective, initial evaluations of sorbents and the process/equipment were completed. First the sorbents were evaluated using a temperature swing adsorption process at the laboratory scale in a fixed-bed apparatus. A slipstream reactor designed to treat flue gas produced by coal-fired generation of nominally 1 kWe was designed and constructed, which was used to evaluate the most promising materials on a more meaningful scale using actual flue gas. In a concurrent effort, commercial-scale processes and equipment options were also evaluated for their applicability to sorbent-based CO{sub 2} capture. A cost analysis was completed that can be used to direct future technology development efforts. ADA completed an extensive sorbent screening program funded primarily through this project, DOE NETL cooperative agreement DE-NT0005649, with support from the Electric Power Research Institute (EPRI) and other industry participants. Laboratory screening tests were completed on simulated and actual flue gas using simulated flue gas and an automated fixed bed system. The following types and quantities of sorbents were evaluated: 87 supported amines; 31 carbon based materials; 6 zeolites; 7 supported carbonates (evaluated under separate funding); and 10 hydrotalcites. Sorbent evaluations were conducted to characterize materials and down-select promising candidates for further testing at the slipstream scale. More than half of the materials evaluated during this program were supported amines. Based on the laboratory screening four supported amine sorbents were selected for evaluation at the 1 kW scale at two different

  9. Concentration and immobilization of 137Cs from liquid radioactive waste using sorbents based on hydrated titanium and zirconium oxides

    Science.gov (United States)

    Voronina, A. V.; Noskova, A. Y.; Gritskevich, E. Y.; Mashkovtsev, M. A.; Semenishchev, V. S.

    2017-09-01

    The possibility of use of sorbents based on hydrated titanium and zirconium oxides (T-3A, T-35, NPF-HTD) for concentration and immobilization of 137Cs from liquid radioactive waste of various chemical composition (fresh water, seawater, solutions containing NaNO3, ammonium acetate, EDTA) was evaluated. It was shown that the NPF-HTD and T-35 sorbents separate 137Cs from fresh water and seawater with distribution coefficients as high as 6.2.104 and 6.1.104, 4.0.105 and 1.6.105 L kg-1 respectively; in 1 M ammonium acetate these values were 2.0.103 and 1.0.103 L kg-1. The NPF-HTD sorbent showed the highest selectivity for cesium in NaNO3 solution: cesium distribution coefficients in 1M NaNO3 was 1.4.106 L kg-1. All studied sorbents are suitable for deactivation of solutions containing EDTA. Cesium distribution coefficients were around 102-103 L kg-1 depending on EDTA concentration. Chemical stability of the sorbents was also studied. It was shown that 137Cs leaching rate from all sorbents meet the requirements for matrix materials.

  10. Imprint-coating synthesis of selective functionalized ordered mesoporous sorbents for separation and sensors

    Science.gov (United States)

    Dai, Sheng; Burleigh, Mark C.; Shin, Yongsoon

    2001-01-01

    The present invention relates generally to mesoporous sorbent materials having high capacity, high selectivity, fast kinetics, and molecular recognition capability. The invention also relates to a process for preparing these mesoporous substrates through molecular imprinting techniques which differ from convention techniques in that a template molecule is bound to one end of bifunctional ligands to form a complex prior to binding of the bifunctional ligands to the substrate. The present invention also relates to methods of using the mesoporous sorbent materials, for example, in the separation of toxic metals from process effluents, paints, and other samples; detection of target molecules, such as amino acids, drugs, herbicides, fertilizers, and TNT, in samples; separation and/or detection of substances using chromatography; imaging agents; sensors; coatings; and composites.

  11. Ruthenium complexing in sorption by granulated sorbents with ethylene diamine and diethyl amine groups

    International Nuclear Information System (INIS)

    Simanova, S.A.; Kolmakova, A.I.; Konovalov, L.V.; Kukushkin, Yu.N.; Kalalova, E.

    1986-01-01

    The sorption process of ruthenium (4) chlorocomplexes - K 2 (RuCl 6 ) macroporous granulated copolymers of glycidylmethacrylate ethylene dimethacrylate with ethylene diamine and diethyl amine has been studied. Sorption has been carried out under the static conditions (at 20 and 98 deg C) from 0.1-2.0 MxHCl and 1.0 M NaCl solutions. It is established that the sorption from acidic solutions proceeds according to anion exchange mechanism with formation of onium chlorocomplexes in the sorbent phase, subjecting to Anderson regrouping during the heating. During the sorption from neutral solutions the second-sphere coordination of polymer amino groups accirs near ruthenium atom and amino-chloride complexes are formed in the sorbent phase

  12. Successful experience with limestone and other sorbents for combustion of biomass in fluid bed power boilers

    Energy Technology Data Exchange (ETDEWEB)

    Coe, D.R. [LG& E Power Systems, Inc., Irvine, CA (United States)

    1993-12-31

    This paper presents the theoretical and practical advantages of utilizing limestone and other sorbents during the combustion of various biomass fuels for the reduction of corrosion and erosion of boiler fireside tubing and refractory. Successful experiences using a small amount of limestone, dolomite, kaolin, or custom blends of aluminum and magnesium compounds in fluid bed boilers fired with biomass fuels will be discussed. Electric power boiler firing experience includes bubbling bed boilers as well as circulating fluid bed boilers in commercial service on biomass fuels. Forest sources of biomass fuels fired include wood chips, brush chips, sawmill waste wood, bark, and hog fuel. Agricultural sources of biomass fuels fired include grape vine prunings, bean straw, almond tree chips, walnut tree chips, and a variety of other agricultural waste fuels. Additionally, some urban sources of wood fuels have been commercially burned with the addition of limestone. Data presented includes qualitative and quantitative analyses of fuel, sorbent, and ash.

  13. Use of synthetic zeolites and other inorganic sorbents for the removal of radionuclides from aqueous wastes

    International Nuclear Information System (INIS)

    Samantha, S.K.; Singh, I.J.; Jain, S.; Sathi, S.; Venkatesan, K.; Ramaswamy, M.; Theyyunni, T.K.; Siddiqui, H.R.

    1997-01-01

    Several synthetic zeolites and inorganic sorbents were tested in the laboratory for the sorption of various radionuclides present in radioactive aqueous waste streams originating from nuclear installations. The sorption of the critical radionuclides like 137 Cs, 90 Sr and 60 Co from level waste solutions was studied using the synthetic zeolites 4A, 13X and AR1 of Indian origin. Granulated forms of ammonium molybdophosphate and CaSO 4 -BaSO 4 eutectoid were tested for the sorption of cesium and strontium respectively, from acidic solutions. The removal of radiostrontium from alkaline salt-loaded intermediate level reprocessing wastes was studied using hydrous ferric oxide-activated carbon composite sorbent, hydrous titania and hydrous manganese dioxide.. The results of these investigations are expected to be of value in formulating radioactive waste treatment schemes for achieving high decontamination and volume reduction factors. (author). 12 refs, 5 figs, 18 tabs

  14. Heat recovery from sorbent-based CO.sub.2 capture

    Science.gov (United States)

    Jamal, Aqil; Gupta, Raghubir P

    2015-03-10

    The present invention provides a method of increasing the efficiency of exothermic CO.sub.2 capture processes. The method relates to withdrawing heat generated during the exothermic capture of CO.sub.2 with various sorbents via heat exchange with a working fluid. The working fluid is provided at a temperature and pressure such that it is in the liquid state, and has a vaporization temperature in a range such that the heat arising from the reaction of the CO.sub.2 and the sorbent causes a phase change from liquid to vapor state in whole or in part and transfers heat from to the working fluid. The resulting heated working fluid may subsequently be used to generate power.

  15. CO.sub.2 removal sorbent composition with high chemical stability during multiple cycles

    Science.gov (United States)

    Siriwardane, Ranjani V.; Rosencwaig, Shira

    2015-09-22

    Disclosed herein is a clay-alkali-amine CO.sub.2 sorbent composition prepared by integrating a clay substrate, basic alkali salt, and amine liquid. The basic alkali salt is present relative to the clay substrate in a weight ratio of from about 1 part to about 50 parts per 100 parts of the clay substrate. The amine liquid is present relative to a clay-alkali combination in a weight ratio of from about 1 part to about 10 parts per 10 parts of the clay-alkali combination. The clay-alkali-amine C02 sorbent is particularly advantageous for low temperature CO.sub.2 removal cycles in a gas stream having a C02 concentration less than around 2000 ppm and an oxygen con