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Sample records for advanced oxidation methods

  1. Advances in methods for detection of anaerobic ammonium oxidizing (anammox) bacteria.

    PubMed

    Li, Meng; Gu, Ji-Dong

    2011-05-01

    Anaerobic ammonium oxidation (anammox), the biochemical process oxidizing ammonium into dinitrogen gas using nitrite as an electron acceptor, has only been recognized for its significant role in the global nitrogen cycle not long ago, and its ubiquitous distribution in a wide range of environments has changed our knowledge about the contributors to the global nitrogen cycle. Currently, several groups of methods are used in detection of anammox bacteria based on their physiological and biochemical characteristics, cellular chemical composition, and both 16S rRNA gene and selective functional genes as biomarkers, including hydrazine oxidoreductase and nitrite reductase encoding genes hzo and nirS, respectively. Results from these methods coupling with advances in quantitative PCR, reverse transcription of mRNA genes and stable isotope labeling have improved our understanding on the distribution, diversity, and activity of anammox bacteria in different environments both natural and engineered ones. In this review, we summarize these methods used in detection of anammox bacteria from various environments, highlight the strengths and weakness of these methods, and also discuss the new development potentials on the existing and new techniques in the future.

  2. ADVANCED OXIDATION PROCESS

    SciTech Connect

    Dr. Colin P. Horwitz; Dr. Terrence J. Collins

    2003-11-04

    The removal of recalcitrant sulfur species, dibenzothiophene and its derivatives, from automotive fuels is an integral component in the development of cleaner burning and more efficient automobile engines. Oxidative desulfurization (ODS) wherein the dibenzothiophene derivative is converted to its corresponding sulfoxide and sulfone is an attractive approach to sulfur removal because the oxidized species are easily extracted or precipitated and filtered from the hydrocarbon phase. Fe-TAML{reg_sign} activators of hydrogen peroxide (TAML is Tetra-Amido-Macrocyclic-Ligand) catalytically convert dibenzothiophene and its derivatives rapidly and effectively at moderate temperatures (50-60 C) and ambient pressure to the corresponding sulfoxides and sulfones. The oxidation process can be performed in both aqueous systems containing alcohols such as methanol, ethanol, or t-butanol, and in a two-phase hydrocarbon/aqueous system containing tert-butanol or acetonitrile. In the biphasic system, essentially complete conversion of the DBT to its oxidized products can be achieved using slightly longer reaction times than in homogeneous solution. Among the key features of the technology are the mild reaction conditions, the very high selectivity where no over oxidation of the sulfur compounds occurs, the near stoichiometric use of hydrogen peroxide, the apparent lack of degradation of sensitive fuel components, and the ease of separation of oxidized products.

  3. Novel imazethapyr detoxification applying advanced oxidation processes.

    PubMed

    Stathis, Ioannis; Hela, Dimitra G; Scrano, Laura; Lelario, Filomena; Emanuele, Lucia; Bufo, Sabino A

    2011-01-01

    Different degradation methods have been applied to assess the suitability of advanced oxidation process (AOPs) to promote mineralization of imazethapyr [(RS)-5-ethyl-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)nicotinic acid], a widely used imidazolinone class herbicide, the persistence of which has been demonstrated in surface and ground waters destined to human uses. Independent of the oxidation process assessed, the decomposition of imazethapyr always followed a pseudo-first order kinetic. The direct UV-irradiation (UV) of the herbicide as well as its oxidation with ozone (O₃), and hydrogen peroxide tied to UV-irradiation (H₂O₂/UV) were sufficiently slow to permit the identification of intermediate products, the formation pathway of which has been proposed. Ozonation joined to UV-irradiation (O₃/UV), ozonation joined to titanium dioxide photo-catalysis (TiO₂/UV+O₃), sole photo-catalysis (TiO₂/UV), and photo-catalysis reinforced with hydrogen peroxide-oxidation (TiO₂/UV+H₂O₂) were characterized by a faster degradation and rapid formation of a lot of small molecules, which were quickly degraded to complete mineralization. The most effective oxidation methods were those using titanium dioxide photo-catalysis enhanced either by ozonation or hydrogen peroxide. Most of all, these last processes were useful to avoid the development of dangerous by-products. PMID:21726140

  4. Oxidation of advanced steam turbine alloys

    SciTech Connect

    Holcomb, G.R.; Covino, B.S., Jr.; Bullard, S.J.; Ziomek-Moroz, M.

    2006-03-01

    Advanced or ultra supercritical (USC) steam power plants offer the promise of higher efficiencies and lower emissions. Current goals of the U.S. Department of Energy’s Advanced Power Systems Initiatives include coal generation at 60% efficiency, which would require steam temperatures of up to 760°C. This research examines the steamside oxidation of advanced alloys for use in USC systems, with emphasis placed on alloys for high- and intermediate-pressure turbine sections.

  5. A general method of fabricating flexible spinel-type oxide/reduced graphene oxide nanocomposite aerogels as advanced anodes for lithium-ion batteries.

    PubMed

    Zeng, Guobo; Shi, Nan; Hess, Michael; Chen, Xi; Cheng, Wei; Fan, Tongxiang; Niederberger, Markus

    2015-04-28

    High-capacity anode materials for lithium ion batteries (LIBs), such as spinel-type metal oxides, generally suffer from poor Li(+) and e(-) conductivities. Their drastic crystal structure and volume changes, as a result of the conversion reaction mechanism with Li, severely impede the high-rate and cyclability performance toward their practical application. In this article, we present a general and facile approach to fabricate flexible spinel-type oxide/reduced graphene oxide (rGO) composite aerogels as binder-free anodes where the spinel nanoparticles (NPs) are integrated in an interconnected rGO network. Benefiting from the hierarchical porosity, conductive network and mechanical stability constructed by interpenetrated rGO layers, and from the pillar effect of NPs in between rGO sheets, the hybrid system synergistically enhances the intrinsic properties of each component, yet is robust and flexible. Consequently, the spinel/rGO composite aerogels demonstrate greatly enhanced rate capability and long-term stability without obvious capacity fading for 1000 cycles at high rates of up to 4.5 A g(-1) in the case of CoFe2O4. This electrode design can successfully be applied to several other spinel ferrites such as MnFe2O4, Fe3O4, NiFe2O4 or Co3O4, all of which lead to excellent electrochemical performances.

  6. Oxidation of alloys for advanced steam turbines

    SciTech Connect

    Holcomb, Gordon R.; Covino, Bernard S., Jr.; Bullard, Sophie J.; Cramer, Stephen D.; Ziomek-Moroz, M.

    2005-01-01

    Ultra supercritical (USC) power plants offer the promise of higher efficiencies and lower emissions. Current goals of the U.S. Department of Energy’s Advanced Power Systems Initiatives include coal generation at 60% efficiency, which would require steam temperatures of up to 760°C. This research examines the steamside oxidation of advanced alloys for use in USC systems, with emphasis placed on alloys for high- and intermediate-pressure turbine sections.

  7. HANDBOOK ON ADVANCED PHOTOCHEMICAL OXIDATION PROCESSES

    EPA Science Inventory

    This handbook summarizes commercial-scale system performance and cost data for advanced photochemical oxidation (APO) treatment of contaminated water, air, and solids. Similar information from pilot- and bench-scale evaluations of APO processes is also included to supplement the...

  8. HANDBOOK ON ADVANCED NONPHOTOCHEMICAL OXIDATION PROCESSES

    EPA Science Inventory

    The purpose of this handbook is to summarize commercial-scale system performance and cost data for advanced nonphotochemical oxidation (ANPO) treatment of contaminated water, air, and soil. Similar information from pilot-and bench-scale evaluations of ANPO processes is also inclu...

  9. Response surface method for the optimisation of micropollutant removal in municipal wastewater treatment plant effluent with the UV/H2O2 advanced oxidation process.

    PubMed

    Schulze-Hennings, U; Pinnekamp, J

    2013-01-01

    Experiments with the ultraviolet (UV)/H2O2 advanced oxidation process (AOP) were conducted to investigate the abatement of micropollutants in wastewater treatment plant effluent. The fluence and the starting concentration of H2O2 in a bench-scale batch reactor were varied according to response surface method (RSM) to examine their influence on the treatment efficiency. It was shown that the investigated AOP is very effective for the abatement of micropollutants with conversion rates typically higher than 90%. Empirical relationships between fluence, H2O2 dosage and the resulting concentration of micropollutants were established by RSM. By this means it was shown that X-ray-contrast media had been degraded only by UV light. Nevertheless, most substances were degraded by the combination of UV irradiation and H2O2. Based on RSM an optimisation of multiple responses was conducted to find the minimal fluence and H2O2 dosage that are needed to reach an efficient abatement of micropollutants. PMID:23656952

  10. Oxidative Lipidomics Coming of Age: Advances in Analysis of Oxidized Phospholipids in Physiology and Pathology

    PubMed Central

    Pitt, Andrew R.

    2015-01-01

    Abstract Significance: Oxidized phospholipids are now well recognized as markers of biological oxidative stress and bioactive molecules with both pro-inflammatory and anti-inflammatory effects. While analytical methods continue to be developed for studies of generic lipid oxidation, mass spectrometry (MS) has underpinned the advances in knowledge of specific oxidized phospholipids by allowing their identification and characterization, and it is responsible for the expansion of oxidative lipidomics. Recent Advances: Studies of oxidized phospholipids in biological samples, from both animal models and clinical samples, have been facilitated by the recent improvements in MS, especially targeted routines that depend on the fragmentation pattern of the parent molecular ion and improved resolution and mass accuracy. MS can be used to identify selectively individual compounds or groups of compounds with common features, which greatly improves the sensitivity and specificity of detection. Application of these methods has enabled important advances in understanding the mechanisms of inflammatory diseases such as atherosclerosis, steatohepatitis, leprosy, and cystic fibrosis, and it offers potential for developing biomarkers of molecular aspects of the diseases. Critical Issues and Future Directions: The future in this field will depend on development of improved MS technologies, such as ion mobility, novel enrichment methods and databases, and software for data analysis, owing to the very large amount of data generated in these experiments. Imaging of oxidized phospholipids in tissue MS is an additional exciting direction emerging that can be expected to advance understanding of physiology and disease. Antioxid. Redox Signal. 22, 1646–1666. PMID:25694038

  11. Advanced oxidation processes with coke plant wastewater treatment.

    PubMed

    Krzywicka, A; Kwarciak-Kozłowska, A

    2014-01-01

    The aim of this study was to determine the most efficient method of coke wastewater treatment. This research examined two processes - advanced oxidation with Fenton and photo-Fenton reaction. It was observed that the use of ultraviolet radiation with Fenton process had a better result in removal of impurities.

  12. Treatment of rice straw hemicellulosic hydrolysates with advanced oxidative processes: a new and promising detoxification method to improve the bioconversion process

    PubMed Central

    2013-01-01

    Background The use of lignocellulosic constituents in biotechnological processes requires a selective separation of the main fractions (cellulose, hemicellulose and lignin). During diluted acid hydrolysis for hemicellulose extraction, several toxic compounds are formed by the degradation of sugars and lignin, which have ability to inhibit microbial metabolism. Thus, the use of a detoxification step represents an important aspect to be considered for the improvement of fermentation processes from hydrolysates. In this paper, we evaluated the application of Advanced Oxidative Processes (AOPs) for the detoxification of rice straw hemicellulosic hydrolysate with the goal of improving ethanol bioproduction by Pichia stipitis yeast. Aiming to reduce the toxicity of the hemicellulosic hydrolysate, different treatment conditions were analyzed. The treatments were carried out according to a Taguchi L16 orthogonal array to evaluate the influence of Fe+2, H2O2, UV, O3 and pH on the concentration of aromatic compounds and the fermentative process. Results The results showed that the AOPs were able to remove aromatic compounds (furan and phenolic compounds derived from lignin) without affecting the sugar concentration in the hydrolysate. Ozonation in alkaline medium (pH 8) in the presence of H2O2 (treatment A3) or UV radiation (treatment A5) were the most effective for hydrolysate detoxification and had a positive effect on increasing the yeast fermentability of rice straw hemicellulose hydrolysate. Under these conditions, the higher removal of total phenols (above 40%), low molecular weight phenolic compounds (above 95%) and furans (above 52%) were observed. In addition, the ethanol volumetric productivity by P. stipitis was increased in approximately twice in relation the untreated hydrolysate. Conclusion These results demonstrate that AOPs are a promising methods to reduce toxicity and improve the fermentability of lignocellulosic hydrolysates. PMID:23414668

  13. Advanced oxidation process sanitization of eggshell surfaces.

    PubMed

    Gottselig, Steven M; Dunn-Horrocks, Sadie L; Woodring, Kristy S; Coufal, Craig D; Duong, Tri

    2016-06-01

    The microbial quality of eggs entering the hatchery represents an important critical control point for biosecurity and pathogen reduction programs in integrated poultry production. The development of safe and effective interventions to reduce microbial contamination on the surface of eggs will be important to improve the overall productivity and microbial food safety of poultry and poultry products. The hydrogen peroxide (H2O2) and ultraviolet (UV) light advanced oxidation process is a potentially important alternative to traditional sanitizers and disinfectants for egg sanitation. The H2O2/UV advanced oxidation process was demonstrated previously to be effective in reducing surface microbial contamination on eggs. In this study, we evaluated treatment conditions affecting the efficacy of H2O2/UV advanced oxidation in order to identify operational parameters for the practical application of this technology in egg sanitation. The effect of the number of application cycles, UV intensity, duration of UV exposure, and egg rotation on the recovery of total aerobic bacteria from the surface of eggs was evaluated. Of the conditions evaluated, we determined that reduction of total aerobic bacteria from naturally contaminated eggs was optimized when eggs were sanitized using 2 repeated application cycles with 5 s exposure to 14 mW cm(-2) UV light, and that rotation of the eggs between application cycles was unnecessary. Additionally, using these optimized conditions, the H2O2/UV process reduced Salmonella by greater than 5 log10 cfu egg(-1) on the surface of experimentally contaminated eggs. This study demonstrates the potential for practical application of the H2O2/UV advanced oxidation process in egg sanitation and its effectiveness in reducing Salmonella on eggshell surfaces. PMID:27030693

  14. Advances in Mechanisms of Anti-oxidation

    PubMed Central

    Ma, Qiang

    2016-01-01

    Reactive oxygen species (ROS) are a family of molecules that are continuously produced from oxygen consumption in aerobic cells. Controlled generation of ROS in normal cells serves useful purposes to regulate important cellular processes such as cell proliferation, inflammation, and immune response, but overproduction of ROS causes oxidative stress that contributes to the development of cancer, chronic disease, and aging. These hugely different consequences of ROS exposure demand a carefully balanced control of ROS production and disposition, which is largely achieved through the body’s elaborate antioxidant system. The human antioxidant system consists of small antioxidants, antioxidant proteins, ROS-metabolizing enzymes, as well as many regulator proteins that mediate adaptive responses to oxidant stress. How such a complex system reacts with oxidants and achieves the required specificity and sensitivity for proper anti-oxidation is incompletely understood. In this respect, new advances in the understanding of the chemistry that determines the reaction of a given oxidant or antioxidant with a protein target provide considerable insights into these and related questions. The findings hold certain promise for new drug development for preventing and treating diseases associated with oxidant tissue damage. PMID:24641954

  15. Characterization of advanced oxidation regenerated GACs

    SciTech Connect

    Singh, J.; Cannon, F.S.

    1995-11-01

    Industrial and manufacturing processes that employ organic solvents, such as pharmaceutical production, spray booth coating applications, and petrochemical processing, constitute a major source of airborne volatile organic contaminants (VOCs) and hazardous air pollutants (HAPs). VOCs released into the atmosphere react with sunlight to create photochemical smog, oxidants and other pollutants, all of which are considered harmful to animal and plant life. There is thus a need for effective air pollution remediation technologies for such facilities. This paper explores the effects of regeneration by means of advanced oxidation involving UV and ozone, on several properties of granular activated carbons (GACs). The effects of reduction in surface areas and pore volumes, and surface oxidation due to this process of regeneration, on adsorption capacities of some model VOCs is investigated.

  16. Joining of Oxide Dispersion Strengthened Steels for Advanced Reactors

    NASA Astrophysics Data System (ADS)

    Baker, B. W.; Brewer, L. N.

    2014-12-01

    The design, manufacture, and experimental analysis of structural materials capable of operation in the high temperatures, corrosive environments, and radiation damage spectra of future reactor designs remain one of the key pacing items for advanced reactor designs. The most promising candidate structural materials are vanadium-based refractory alloys, silicon carbide composites and oxide dispersion strengthened steels. Of these, oxide dispersion strengthened steels are a likely near-term candidate to meet required demands. This paper reviews different variants of oxide dispersion strengthened steels and discusses their capability with regard to high-temperature strength, corrosion resistance, and radiation damage resistance. Additionally, joining of oxide dispersion strengthened steels, which has been cited as a limiting factor preventing their use, is addressed and reviewed. Specifically, friction stir welding of these steels is reviewed as a promising joining method for oxide dispersion strengthened steels.

  17. Comparison among the methods for hydrogen peroxide measurements to evaluate advanced oxidation processes: Application of a spectrophotometric method using copper(II) ion and 2,9-dimethyl-1,10-phenanthroline

    SciTech Connect

    Kosaka, Koji; Yamada, Harumi; Matsui, Saburo; Echigo, Shinya; Shishida, Kenichi

    1998-12-01

    Hydrogen peroxide (H{sub 2}O{sub 2}) in the range of several tens to several hundreds of micromoles per liter is usually added to the process water in advanced oxidation processes (AOPs). In this study, a spectrophotometric method using copper(II) ion and 2,9-dimethyl-1, 10-phenanthroline (DMP) for measuring H{sub 2}O{sub 2} concentration was compared with other methods [i.e., spectrophotometric methods using titanium oxalate and N,N-diethyl-p-phenylenediamine (DPD) and a fluorometric method using p-hydroxyphenyl acetic acid (POHPAA)]. Particular attention was paid to sensitivities and effects of coexisting substances. The most sensitive method was the fluorometric method, followed in order by DPD, DMP, and the titanium oxalate colorimetric method; their detection limits in 1-cm cells were 0.16, 0.77, 0.80, and 29 {micro}M, respectively. Therefore, the DMP method was found to be reasonably sensitive when applied to AOPs. In the DMP method, copper(II)-DMP complexes react with humic acid, and colored chemicals are produced. However, the slopes of the calibration curves of H{sub 2}O{sub 2} containing up to 10 mg of C L{sup {minus}1} from humic acid did not change significantly as compared to that in ultrapure water. The effect of chlorine on the DMP method was not observed up to at least 23 {micro}M (0.8 mg of Cl L{sup {minus}1}) of free chlorine, although the DPD and fluorometric methods are known to be interfered by chlorine. From this study, it was concluded that the DMP method is suitable to be used in AOPs.

  18. Advanced epidemiologic and analytical methods.

    PubMed

    Albanese, E

    2016-01-01

    Observational studies are indispensable for etiologic research, and are key to test life-course hypotheses and improve our understanding of neurologic diseases that have long induction and latency periods. In recent years a plethora of advanced design and analytic techniques have been developed to strengthen the robustness and ultimately the validity of the results of observational studies, and to address their inherent proneness to bias. It is the responsibility of clinicians and researchers to critically appraise and appropriately contextualize the findings of the exponentially expanding scientific literature. This critical appraisal should be rooted in a thorough understanding of advanced epidemiologic methods and techniques commonly used to formulate and test relevant hypotheses and to keep bias at bay. PMID:27637951

  19. Induced effects of advanced oxidation processes

    NASA Astrophysics Data System (ADS)

    Liu, Peng; Li, Chaolin; Zhao, Zhuanjun; Lu, Gang; Cui, Haibo; Zhang, Wenfang

    2014-02-01

    Hazardous organic wastes from industrial, military, and commercial activities represent one of the greatest challenges to human beings. Advanced oxidation processes (AOPs) are alternatives to the degradation of those organic wastes. However, the knowledge about the exact mechanisms of AOPs is still incomplete. Here we report a phenomenon in the AOPs: induced effects, which is a common property of combustion reaction. Through analysis EDTA oxidation processes by Fenton and UV-Fenton system, the results indicate that, just like combustion, AOPs are typical induction reactions. One most compelling example is that pre-feeding easily oxidizable organic matter can promote the oxidation of refractory organic compound when it was treated by AOPs. Connecting AOPs to combustion, it is possible to achieve some helpful enlightenment from combustion to analyze, predict and understand AOPs. In addition, we assume that maybe other oxidation reactions also have induced effects, such as corrosion, aging and passivation. Muchmore research is necessary to reveal the possibilities of induced effects in those fields.

  20. Induced effects of advanced oxidation processes

    PubMed Central

    Liu, Peng; Li, Chaolin; Zhao, Zhuanjun; Lu, Gang; Cui, Haibo; Zhang, Wenfang

    2014-01-01

    Hazardous organic wastes from industrial, military, and commercial activities represent one of the greatest challenges to human beings. Advanced oxidation processes (AOPs) are alternatives to the degradation of those organic wastes. However, the knowledge about the exact mechanisms of AOPs is still incomplete. Here we report a phenomenon in the AOPs: induced effects, which is a common property of combustion reaction. Through analysis EDTA oxidation processes by Fenton and UV-Fenton system, the results indicate that, just like combustion, AOPs are typical induction reactions. One most compelling example is that pre-feeding easily oxidizable organic matter can promote the oxidation of refractory organic compound when it was treated by AOPs. Connecting AOPs to combustion, it is possible to achieve some helpful enlightenment from combustion to analyze, predict and understand AOPs. In addition, we assume that maybe other oxidation reactions also have induced effects, such as corrosion, aging and passivation. Muchmore research is necessary to reveal the possibilities of induced effects in those fields. PMID:24503715

  1. Novel method for controlled oxidation

    SciTech Connect

    Benjamin, B.M.; Raaen, V.F.

    1981-01-01

    The purpose of this paper is to describe a novel method for the oxidative degradation of coal or other organic material. The procedure is potentially useful for structure determination. As originally conceived, this method was intended for use with aqueous potassium permanganate as oxidant, but it is equally applicable with other oxidizing agents. Sodium hyprochlorite can be substituted for KMnO/sub 4/ except that controlling the pH and monitoring the end pilot become more difficult. Results with potassium permanganate only are described here but sodium hypochlorite was tried. An advantageous feature of the method is the simultaneous removal of soluble products from further contact with oxidizing agent as the oxidizing agent attacks the substrate. In principle, the experimental approach resembles that of column chromatography. Any oxidative degradation of a natural product for structure determination is of little use if carried out too far; for example, to the smallest, most oxidation-resistant materials such as carbon dioxide, acetic acid, and benzoic acid. Potassium permanganate oxidations of reactive species such as coal and kerogen are particularly difficult to control. Partially oxidized fragments which go into solution can be attacked more effectively than the solid starting phase, a situation which results in loss of structural information. Another difficulty is that phenolic materials can undergo coupling reactions thus generating larger molecules and giving misleading results due to a larger number of substituents. The procedure used is described.

  2. Removal of arsenic, phosphates and ammonia from well water using electrochemical/chemical methods and advanced oxidation: a pilot plant approach.

    PubMed

    Orescanin, Visnja; Kollar, Robert; Nad, Karlo; Halkijevic, Ivan; Kuspilic, Marin; Findri Gustek, Stefica

    2014-01-01

    The purpose of this work was to develop a pilot plant purification system and apply it to groundwater used for human consumption, containing high concentrations of arsenic and increased levels of phosphates, ammonia, mercury and color. The groundwater used was obtained from the production well in the Vinkovci County (Eastern Croatia). Due to a complex composition of the treated water, the purification system involved a combined electrochemical treatment, using iron and aluminum electrode plates with simultaneous ozonation, followed by a post-treatment with UV, ozone and hydrogen peroxide. The removal of the contaminant with the waste sludge collected during the electrochemical treatment was also tested. The combined electrochemical and advanced oxidation treatment resulted in the complete removal of arsenic, phosphates, color, turbidity, suspended solids and ammonia, while the removal of other contaminants of interest was up to 96.7%. Comparable removal efficiencies were obtained by using waste sludge as a coagulant.

  3. ADVANCED OXIDATION TECHNOLOGIES FOR THE TREATMENT OF CONTAMINATED GROUNDWATER

    EPA Science Inventory

    This paper presents information on two pilot-field appliations of advanced oxidation technologies for contaminated groundwater with organis. The two UV/oxidation technologies were developed by Ultrox International of Santa Ana, California and Peroxidatrion Systems, Inc. of Tucso...

  4. Electrochemical advanced oxidation processes: today and tomorrow. A review.

    PubMed

    Sirés, Ignasi; Brillas, Enric; Oturan, Mehmet A; Rodrigo, Manuel A; Panizza, Marco

    2014-01-01

    In recent years, new advanced oxidation processes based on the electrochemical technology, the so-called electrochemical advanced oxidation processes (EAOPs), have been developed for the prevention and remediation of environmental pollution, especially focusing on water streams. These methods are based on the electrochemical generation of a very powerful oxidizing agent, such as the hydroxyl radical ((•)OH) in solution, which is then able to destroy organics up to their mineralization. EAOPs include heterogeneous processes like anodic oxidation and photoelectrocatalysis methods, in which (•)OH are generated at the anode surface either electrochemically or photochemically, and homogeneous processes like electro-Fenton, photoelectro-Fenton, and sonoelectrolysis, in which (•)OH are produced in the bulk solution. This paper presents a general overview of the application of EAOPs on the removal of aqueous organic pollutants, first reviewing the most recent works and then looking to the future. A global perspective on the fundamentals and experimental setups is offered, and laboratory-scale and pilot-scale experiments are examined and discussed.

  5. Saltstone Oxidation Study: Leaching Method

    SciTech Connect

    Langton, C. A.; Stefanko, D. B.; Burns, H. H.

    2013-02-24

    Cementitious waste forms can be designed to chemically stabilize selected contaminants, such as Tc{sup +7} and Cr{sup +6}, by chemically reduction to lower valance states, Tc{sup +4} and Cr{sup +3}, respectively, and precipitation of these species in alkaline media as low solubility solid phases. Data for oxidation of this type of cementitious waste form cured under field conditions as a function of time is required for predicting the performance of the waste form and disposal facility. The rate of oxidation (oxidation front advancement) is an important parameter for predicting performance because the solubilities of some radionuclide contaminants, e.g., technetium, are a function of the oxidation state. A non-radioactive experiment was designed for quantifying the oxidation front advancement using chromium, as an approximate redox-sensitive surrogate (Cr{sup +6} / Cr{sup +3}) for technetium (Tc{sup +7} / Tc{sup +4}). Nonradioactive cementitious waste forms were prepared in the laboratory and cured under both laboratory and ?field conditions.? Laboratory conditions were ambient temperature and sealed sample containers. Field conditions were approximated by curing samples in open containers which were placed inside a plastic container stored outdoors at SRS. The container had a lid and was instrumented with temperature and humidity probes. Subsamples as thin as 0.2 mm were taken as a function of distance from the exposed surface of the as-cast sample. The subsamples were leached and the leachates were analyzed for chromium, nitrate, nitrite and sodium. Nitrate, nitrite, and sodium concentrations were used to provide baseline data because these species are not chemically retained in the waste form matrix to any significant extent and are not redox sensitive. ?Effective? oxidation fronts for Cr were measured for samples containing 1000, 500 and 20 mg/kg Cr added as soluble sodium chromate, Na{sub 2}CrO{sub 4}. For a sample cured for 129 days under field conditions

  6. Advanced diagnostic methods in avionics

    NASA Astrophysics Data System (ADS)

    Popyack, Leonard Joseph, Jr.

    Advanced diagnostic systems facilitate further enhancement of reliability and safety of modern aircraft. Unlike classical reliability analyses, addressing specific classes of systems or devices, this research is aimed at the development of methods for assessment of the individual reliability characteristics of particular system components subjected to their unique histories of operational conditions and exposure to adverse environmental factors. Individual reliability characteristics are crucial for the implementation of the most efficient maintenance practice of flight-critical system components, known as "condition-based maintenance." The dissertation presents hardware and software aspects of a computer-based system, Time-Stress Monitoring Device, developed to record, store, and analyze raw data characterizing operational and environmental conditions and performance of electro-mechanical flight control system components and aircraft electronics (avionics). Availability of this data facilitates formulation and solution of such diagnostic problems as estimation of the probability of failure and life expectancy of particular components, failure detection, identification, and prediction. Statistical aspects of system diagnostics are considered. Particular diagnostic procedures utilizing cluster analysis, Bayes' technique, and regression analysis are formulated. Laboratory and simulation experiment that verify the obtained results are provided.

  7. ADVANCED OXIDATION: OXALATE DECOMPOSITION TESTING WITH OZONE

    SciTech Connect

    Ketusky, E.; Subramanian, K.

    2012-02-29

    At the Savannah River Site (SRS), oxalic acid is currently considered the preferred agent for chemically cleaning the large underground Liquid Radioactive Waste Tanks. It is applied only in the final stages of emptying a tank when generally less than 5,000 kg of waste solids remain, and slurrying based removal methods are no-longer effective. The use of oxalic acid is preferred because of its combined dissolution and chelating properties, as well as the fact that corrosion to the carbon steel tank walls can be controlled. Although oxalic acid is the preferred agent, there are significant potential downstream impacts. Impacts include: (1) Degraded evaporator operation; (2) Resultant oxalate precipitates taking away critically needed operating volume; and (3) Eventual creation of significant volumes of additional feed to salt processing. As an alternative to dealing with the downstream impacts, oxalate decomposition using variations of ozone based Advanced Oxidation Process (AOP) were investigated. In general AOPs use ozone or peroxide and a catalyst to create hydroxyl radicals. Hydroxyl radicals have among the highest oxidation potentials, and are commonly used to decompose organics. Although oxalate is considered among the most difficult organic to decompose, the ability of hydroxyl radicals to decompose oxalate is considered to be well demonstrated. In addition, as AOPs are considered to be 'green' their use enables any net chemical additions to the waste to be minimized. In order to test the ability to decompose the oxalate and determine the decomposition rates, a test rig was designed, where 10 vol% ozone would be educted into a spent oxalic acid decomposition loop, with the loop maintained at 70 C and recirculated at 40L/min. Each of the spent oxalic acid streams would be created from three oxalic acid strikes of an F-area simulant (i.e., Purex = high Fe/Al concentration) and H-area simulant (i.e., H area modified Purex = high Al/Fe concentration) after nearing

  8. Highly oxidized graphene oxide and methods for production thereof

    DOEpatents

    Tour, James M.; Kosynkin, Dmitry V.

    2016-08-30

    A highly oxidized form of graphene oxide and methods for production thereof are described in various embodiments of the present disclosure. In general, the methods include mixing a graphite source with a solution containing at least one oxidant and at least one protecting agent and then oxidizing the graphite source with the at least one oxidant in the presence of the at least one protecting agent to form the graphene oxide. Graphene oxide synthesized by the presently described methods is of a high structural quality that is more oxidized and maintains a higher proportion of aromatic rings and aromatic domains than does graphene oxide prepared in the absence of at least one protecting agent. Methods for reduction of graphene oxide into chemically converted graphene are also disclosed herein. The chemically converted graphene of the present disclosure is significantly more electrically conductive than is chemically converted graphene prepared from other sources of graphene oxide.

  9. Advanced oxidation technologies for chemical demilitarization

    SciTech Connect

    Rosocha, L.A.; Korzekwa, R.A.; Monagle, M.; Coogan, J.J.; Tennant, R.A.; Brown, L.F.; Currier, R.P.

    1996-12-31

    This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory. The main project objective was to establish a technical basis for future program development in the area of chemical warfare agent destruction using a Los Alamos-developed advanced oxidation process: a two-stage device consisting of thermal packed-bed reactor (PBR) and a nonthermal plasma (NTP) reactor. Various compounds were evaluated as potential surrogates for chemical warfare (CW) agents. Representative effluent mass balances were projected for future comparisons with incinerators. The design and construction of lab-scale PBR/NTP reactors (consisting of a liquid injection and metering system, electric furnace, condensers, chemical traps, plasma reactors, power supplies, and chemical diagnostics) has been completed. This equipment, the experience gained from chemical-processing experiments, process modeling, and an initial demonstration of the feasibility of closed-loop operation, have provided a technical basis for further demonstrations and program development efforts.

  10. Advanced methods for processing ceramics

    SciTech Connect

    Carter, W.B.

    1997-04-01

    Combustion chemical vapor deposition (combustion CVD) is being developed for the deposition of high temperature oxide coatings. The process is being evaluated as an alternative to more capital intensive conventional coating processes. The thrusts during this reporting period were the development of the combustion CVD process for depositing lanthanum monazite, the determination of the influence of aerosol size on coating morphology, the incorporation of combustion CVD coatings into thermal barrier coatings (TBCs) and related oxidation research, and continued work on the deposition of zirconia-yttria coatings.

  11. Advanced materials for solid oxide fuel cells

    SciTech Connect

    Armstrong, T.R.; Stevenson, J.

    1995-08-01

    The purpose of this research is to improve the properties of the current state-of-the-art materials used for solid oxide fuel cells (SOFCs). The objectives are to: (1) develop materials based on modifications of the state-of-the-art materials; (2) minimize or eliminate stability problems in the cathode, anode, and interconnect; (3) Electrochemically evaluate (in reproducible and controlled laboratory tests) the current state-of-the-art air electrode materials and cathode/electrolyte interfacial properties; (4) Develop accelerated electrochemical test methods to evaluate the performance of SOFCs under controlled and reproducible conditions; and (5) Develop and test materials for use in low-temperature SOFCs. The goal is to modify and improve the current state-of-the-art materials and minimize the total number of cations in each material to avoid negative effects on the materials properties. Materials to reduce potential deleterious interactions, (3) improve thermal, electrical, and electrochemical properties, (4) develop methods to synthesize both state-of-the-art and alternative materials for the simultaneous fabricatoin and consolidation in air of the interconnections and electrodes with the solid electrolyte, and (5) understand electrochemical reactions at materials interfaces and the effects of component composition and processing on those reactions.

  12. SULFATE RADICAL-BASED ADVANCED OXIDATION PROCESSES- ACS MEETING

    EPA Science Inventory

    This paper will present an overview of sulfate radical-based advanced oxidation technologies for the destruction of environmentally toxic chemicals in wastewater, industrial water, groundwater and sources of water supply. The paper will include fundamental aspects of the generati...

  13. Oxidation-Reduction Resistance of Advanced Copper Alloys

    NASA Technical Reports Server (NTRS)

    Greenbauer-Seng, L. (Technical Monitor); Thomas-Ogbuji, L.; Humphrey, D. L.; Setlock, J. A.

    2003-01-01

    Resistance to oxidation and blanching is a key issue for advanced copper alloys under development for NASA's next generation of reusable launch vehicles. Candidate alloys, including dispersion-strengthened Cu-Cr-Nb, solution-strengthened Cu-Ag-Zr, and ODS Cu-Al2O3, are being evaluated for oxidation resistance by static TGA exposures in low-p(O2) and cyclic oxidation in air, and by cyclic oxidation-reduction exposures (using air for oxidation and CO/CO2 or H2/Ar for reduction) to simulate expected service environments. The test protocol and results are presented.

  14. Secondary hospital wastewater detoxification and disinfection by advanced oxidation processes.

    PubMed

    Machado, E L; Kist, L T; Schmidt, R; Hoeltz, J M; Dalberto, D; Alcayaga, E L A

    2007-10-01

    Secondary hospital wastewater treatment was investigated as an alternative to detoxification and disinfection after anaerobic digestion in a hospital located in southern Brazil. Tertiary and secondary effluents were assessed by general parameters. The use of advanced oxidation processes (UV/O3 and UV/TiO2/O3) showed potential capacity for disinfection and detoxification of wastewater effluents. The UV/TiO2/O3 method yielded the best results, decreasing toxicity of EC50 = 65 to nontoxic levels, also reducing MPN/100ml of 1.1 x 10(6) to values less than 2 and increasing wastewater biodegradability. The low energetic consumption of the proposed UV/TiO2/O3 method can be considered operationally advantageous.

  15. Method for plating with metal oxides

    DOEpatents

    Silver, G.L.; Martin, F.S.

    1994-08-23

    A method is disclosed of plating hydrous metal oxides on at least one substrate, which method is indifferent to the electrochemical properties of the substrate, and comprises reacting metallic ions in aqueous solution with an appropriate oxidizing agent such as sodium hypochlorite or calcium sulfite with oxygen under suitable conditions of pH and concentration such that oxidation and precipitation of metal oxide are sufficiently slow to allow satisfactory plating of metal oxide on the substrate. 1 fig.

  16. Method for plating with metal oxides

    SciTech Connect

    Silver, Gary L.; Martin, Frank S.

    1994-08-23

    A method of plating hydrous metal oxides on at least one substrate, which method is indifferent to the electrochemical properties of the substrate, and comprises reacting metallic ions in aqueous solution with an appropriate oxidizing agent such as sodium hypochlorite or calcium sulfite with oxygen under suitable conditions of pH and concentration such that oxidation and precipitation of metal oxide are sufficiently slow to allow satisfactory plating of metal oxide on the substrate.

  17. Advanced reliability methods - A review

    NASA Astrophysics Data System (ADS)

    Forsyth, David S.

    2016-02-01

    There are a number of challenges to the current practices for Probability of Detection (POD) assessment. Some Nondestructive Testing (NDT) methods, especially those that are image-based, may not provide a simple relationship between a scalar NDT response and a damage size. Some damage types are not easily characterized by a single scalar metric. Other sensing paradigms, such as structural health monitoring, could theoretically replace NDT but require a POD estimate. And the cost of performing large empirical studies to estimate POD can be prohibitive. The response of the research community has been to develop new methods that can be used to generate the same information, POD, in a form that can be used by engineering designers. This paper will highlight approaches to image-based data and complex defects, Model Assisted POD estimation, and Bayesian methods for combining information. This paper will also review the relationship of the POD estimate, confidence bounds, tolerance bounds, and risk assessment.

  18. Advanced Fine Particulate Characterization Methods

    SciTech Connect

    Steven Benson; Lingbu Kong; Alexander Azenkeng; Jason Laumb; Robert Jensen; Edwin Olson; Jill MacKenzie; A.M. Rokanuzzaman

    2007-01-31

    The characterization and control of emissions from combustion sources are of significant importance in improving local and regional air quality. Such emissions include fine particulate matter, organic carbon compounds, and NO{sub x} and SO{sub 2} gases, along with mercury and other toxic metals. This project involved four activities including Further Development of Analytical Techniques for PM{sub 10} and PM{sub 2.5} Characterization and Source Apportionment and Management, Organic Carbonaceous Particulate and Metal Speciation for Source Apportionment Studies, Quantum Modeling, and High-Potassium Carbon Production with Biomass-Coal Blending. The key accomplishments included the development of improved automated methods to characterize the inorganic and organic components particulate matter. The methods involved the use of scanning electron microscopy and x-ray microanalysis for the inorganic fraction and a combination of extractive methods combined with near-edge x-ray absorption fine structure to characterize the organic fraction. These methods have direction application for source apportionment studies of PM because they provide detailed inorganic analysis along with total organic and elemental carbon (OC/EC) quantification. Quantum modeling using density functional theory (DFT) calculations was used to further elucidate a recently developed mechanistic model for mercury speciation in coal combustion systems and interactions on activated carbon. Reaction energies, enthalpies, free energies and binding energies of Hg species to the prototype molecules were derived from the data obtained in these calculations. Bimolecular rate constants for the various elementary steps in the mechanism have been estimated using the hard-sphere collision theory approximation, and the results seem to indicate that extremely fast kinetics could be involved in these surface reactions. Activated carbon was produced from a blend of lignite coal from the Center Mine in North Dakota and

  19. Recent advances in lattice Boltzmann methods

    SciTech Connect

    Chen, S.; Doolen, G.D.; He, X.; Nie, X.; Zhang, R.

    1998-12-31

    In this paper, the authors briefly present the basic principles of lattice Boltzmann method and summarize recent advances of the method, including the application of the lattice Boltzmann method for fluid flows in MEMS and simulation of the multiphase mixing and turbulence.

  20. Advanced launch system. Advanced development oxidizer turbopump program

    NASA Astrophysics Data System (ADS)

    1993-10-01

    On May 19, 1989, Pratt & Whitney was awarded contract NAS8-37595 by the National Aeronautics and Space Administration, Marshall Space Flight Center, Huntsville Alabama for an Advanced Development Program (ADP) to design, develop and demonstrate a highly reliable low cost, liquid oxygen turbopump for the Advanced Launch System (ALS). The ALS had an overall goal of reducing the cost of placing payloads in orbit by an order of magnitude. This goal would require a substantial reduction in life cycle costs, with emphasis on recurring costs, compared to current launch vehicles. Engine studies supporting these efforts were made for the Space Transportation Main Engine (STME). The emphasis on low cost required design simplification of components and subsystems such that the ground maintenance and test operations was minimized. The results of the Oxygen Turbopump ADP technology effort would provide data to be used in the STME. Initially the STME baseline was a gas generator cycle engine with a vacuum thrust level of 580,000 lbf. This was later increased to 650,000 lbf and the oxygen turbopump design approach was changed to reflect the new thrust level. It was intended that this ADP program be conducted in two phases. Phase 1, a basic phase, would encompass the preliminary design effort, and Phase II, an optional contract phase to cover design, fabrication and test evaluation of an oxygen turbopump at a component test facility at the NASA John C. Stennis Space Center in Mississippi. The basic phase included preliminary design and analysis, evaluation of low cost concepts, and evaluation of fabrication techniques. The option phase included design of the pump and support hardware, analysis of the final configuration to ensure design integrity, fabrication of hardware to demonstrate low cost, DVS Testing of hardware to verify the design, assembly of the turbopump and full scale turbopump testing. In December 1990, the intent of this ADP to support the design and development was

  1. Advanced launch system. Advanced development oxidizer turbopump program

    NASA Technical Reports Server (NTRS)

    1993-01-01

    On May 19, 1989, Pratt & Whitney was awarded contract NAS8-37595 by the National Aeronautics and Space Administration, Marshall Space Flight Center, Huntsville Alabama for an Advanced Development Program (ADP) to design, develop and demonstrate a highly reliable low cost, liquid oxygen turbopump for the Advanced Launch System (ALS). The ALS had an overall goal of reducing the cost of placing payloads in orbit by an order of magnitude. This goal would require a substantial reduction in life cycle costs, with emphasis on recurring costs, compared to current launch vehicles. Engine studies supporting these efforts were made for the Space Transportation Main Engine (STME). The emphasis on low cost required design simplification of components and subsystems such that the ground maintenance and test operations was minimized. The results of the Oxygen Turbopump ADP technology effort would provide data to be used in the STME. Initially the STME baseline was a gas generator cycle engine with a vacuum thrust level of 580,000 lbf. This was later increased to 650,000 lbf and the oxygen turbopump design approach was changed to reflect the new thrust level. It was intended that this ADP program be conducted in two phases. Phase 1, a basic phase, would encompass the preliminary design effort, and Phase II, an optional contract phase to cover design, fabrication and test evaluation of an oxygen turbopump at a component test facility at the NASA John C. Stennis Space Center in Mississippi. The basic phase included preliminary design and analysis, evaluation of low cost concepts, and evaluation of fabrication techniques. The option phase included design of the pump and support hardware, analysis of the final configuration to ensure design integrity, fabrication of hardware to demonstrate low cost, DVS Testing of hardware to verify the design, assembly of the turbopump and full scale turbopump testing. In December 1990, the intent of this ADP to support the design and development was

  2. Effect of advanced oxidation processes on the micropollutants and the effluent organic matter contained in municipal wastewater previously treated by three different secondary methods.

    PubMed

    Giannakis, Stefanos; Gamarra Vives, Franco Alejandro; Grandjean, Dominique; Magnet, Anoys; De Alencastro, Luiz Felippe; Pulgarin, César

    2015-11-01

    In this study, wastewater from the output of three different secondary treatment facilities (Activated Sludge, Moving Bed Bioreactor and Coagulation-Flocculation) present in the municipal wastewater treatment plant of Vidy, Lausanne (Switzerland), was further treated with various oxidation processes (UV, UV/H2O2, solar irradiation, Fenton, solar photo-Fenton), at laboratory scale. For this assessment, 6 organic micropollutants in agreement with the new environmental legislation requirements in Switzerland were selected (Carbamazepine, Clarithromycin, Diclofenac, Metoprolol, Benzotriazole, Mecoprop) and monitored throughout the treatment. Also, the overall removal of the organic load was assessed. After each secondary treatment, the efficiency of the AOPs increased in the following order: Coagulation-Flocculation < Activated Sludge < Moving Bed Bioreactor, in almost all cases. From the different combinations tested, municipal wastewater subjected to biological treatment followed by UV/H2O2 resulted in the highest elimination levels. Wastewater previously treated by physicochemical treatment demonstrated considerably inhibited micropollutant degradation rates. The degradation kinetics were determined, yielding: k (UV) < k (UV/H2O2) and k (Fenton) < k (solar irradiation) < k (photo-Fenton). Finally, the evolution of global pollution parameters (COD & TOC elimination) was followed and the degradation pathways for the effluent organic matter are discussed.

  3. Effect of advanced oxidation processes on the micropollutants and the effluent organic matter contained in municipal wastewater previously treated by three different secondary methods.

    PubMed

    Giannakis, Stefanos; Gamarra Vives, Franco Alejandro; Grandjean, Dominique; Magnet, Anoys; De Alencastro, Luiz Felippe; Pulgarin, César

    2015-11-01

    In this study, wastewater from the output of three different secondary treatment facilities (Activated Sludge, Moving Bed Bioreactor and Coagulation-Flocculation) present in the municipal wastewater treatment plant of Vidy, Lausanne (Switzerland), was further treated with various oxidation processes (UV, UV/H2O2, solar irradiation, Fenton, solar photo-Fenton), at laboratory scale. For this assessment, 6 organic micropollutants in agreement with the new environmental legislation requirements in Switzerland were selected (Carbamazepine, Clarithromycin, Diclofenac, Metoprolol, Benzotriazole, Mecoprop) and monitored throughout the treatment. Also, the overall removal of the organic load was assessed. After each secondary treatment, the efficiency of the AOPs increased in the following order: Coagulation-Flocculation < Activated Sludge < Moving Bed Bioreactor, in almost all cases. From the different combinations tested, municipal wastewater subjected to biological treatment followed by UV/H2O2 resulted in the highest elimination levels. Wastewater previously treated by physicochemical treatment demonstrated considerably inhibited micropollutant degradation rates. The degradation kinetics were determined, yielding: k (UV) < k (UV/H2O2) and k (Fenton) < k (solar irradiation) < k (photo-Fenton). Finally, the evolution of global pollution parameters (COD & TOC elimination) was followed and the degradation pathways for the effluent organic matter are discussed. PMID:26255127

  4. Oxidation of artificial sweetener sucralose by advanced oxidation processes: a review.

    PubMed

    Sharma, Virender K; Oturan, Mehmet; Kim, Hyunook

    2014-01-01

    Sucralose, a chlorinated carbohydrate, has shown its increased use as an artificial sweetener and persistently exists in wastewater treatment plant effluents and aquatic environment. This paper aims to review possible degradation of sucralose and related carbohydrates by biological, electrochemical, chemical, and advanced oxidation processes. Biodegradation of sucralose in waterworks did not occur significantly. Electrochemical oxidation of carbohydrates may be applied to seek degradation of sucralose. The kinetics of the oxidation of sucralose and the related carbohydrates by different oxidative species is compared. Free chlorine, ozone, and ferrate did not show any potential to degrade sucralose in water. Advanced oxidation processes, generating highly strong oxidizing agent hydroxyl radicals ((•)OH), have demonstrated effectiveness in transforming sucralose in water. The mechanism of oxidation of sucralose by (•)OH is briefly discussed. PMID:24687789

  5. Oxidation of artificial sweetener sucralose by advanced oxidation processes: a review.

    PubMed

    Sharma, Virender K; Oturan, Mehmet; Kim, Hyunook

    2014-01-01

    Sucralose, a chlorinated carbohydrate, has shown its increased use as an artificial sweetener and persistently exists in wastewater treatment plant effluents and aquatic environment. This paper aims to review possible degradation of sucralose and related carbohydrates by biological, electrochemical, chemical, and advanced oxidation processes. Biodegradation of sucralose in waterworks did not occur significantly. Electrochemical oxidation of carbohydrates may be applied to seek degradation of sucralose. The kinetics of the oxidation of sucralose and the related carbohydrates by different oxidative species is compared. Free chlorine, ozone, and ferrate did not show any potential to degrade sucralose in water. Advanced oxidation processes, generating highly strong oxidizing agent hydroxyl radicals ((•)OH), have demonstrated effectiveness in transforming sucralose in water. The mechanism of oxidation of sucralose by (•)OH is briefly discussed.

  6. Oxidation resistant alloys, method for producing oxidation resistant alloys

    DOEpatents

    Dunning, John S.; Alman, David E.

    2002-11-05

    A method for producing oxidation-resistant austenitic alloys for use at temperatures below 800 C. comprising of: providing an alloy comprising, by weight %: 14-18% chromium, 15-18% nickel, 1-3% manganese, 1-2% molybdenum, 2-4% silicon, 0% aluminum and the balance being iron; heating the alloy to 800 C. for between 175-250 hours prior to use in order to form a continuous silicon oxide film and another oxide film. The method provides a means of producing stainless steels with superior oxidation resistance at temperatures above 700 C. at a low cost

  7. Oxidation resistant alloys, method for producing oxidation resistant alloys

    DOEpatents

    Dunning, John S.; Alman, David E.

    2002-11-05

    A method for producing oxidation-resistant austenitic alloys for use at temperatures below 800.degree. C. comprising of: providing an alloy comprising, by weight %: 14-18% chromium, 15-18% nickel, 1-3% manganese, 1-2% molybdenum, 2-4% silicon, 0% aluminum and the balance being iron; heating the alloy to 800.degree. C. for between 175-250 hours prior to use in order to form a continuous silicon oxide film and another oxide film. The method provides a means of producing stainless steels with superior oxidation resistance at temperatures above 700.degree. C. at a low cost

  8. Recent advances in heterogeneous selective oxidation catalysis for sustainable chemistry.

    PubMed

    Guo, Zhen; Liu, Bin; Zhang, Qinghong; Deng, Weiping; Wang, Ye; Yang, Yanhui

    2014-05-21

    Oxidation catalysis not only plays a crucial role in the current chemical industry for the production of key intermediates such as alcohols, epoxides, aldehydes, ketones and organic acids, but also will contribute to the establishment of novel green and sustainable chemical processes. This review is devoted to dealing with selective oxidation reactions, which are important from the viewpoint of green and sustainable chemistry and still remain challenging. Actually, some well-known highly challenging chemical reactions involve selective oxidation reactions, such as the selective oxidation of methane by oxygen. On the other hand some important oxidation reactions, such as the aerobic oxidation of alcohols in the liquid phase and the preferential oxidation of carbon monoxide in hydrogen, have attracted much attention in recent years because of their high significance in green or energy chemistry. This article summarizes recent advances in the development of new catalytic materials or novel catalytic systems for these challenging oxidation reactions. A deep scientific understanding of the mechanisms, active species and active structures for these systems are also discussed. Furthermore, connections among these distinct catalytic oxidation systems are highlighted, to gain insight for the breakthrough in rational design of efficient catalytic systems for challenging oxidation reactions.

  9. Methods for synthesizing metal oxide nanowires

    DOEpatents

    Sunkara, Mahendra Kumar; Kumar, Vivekanand; Kim, Jeong H.; Clark, Ezra Lee

    2016-08-09

    A method of synthesizing a metal oxide nanowire includes the steps of: combining an amount of a transition metal or a transition metal oxide with an amount of an alkali metal compound to produce a mixture; activating a plasma discharge reactor to create a plasma discharge; exposing the mixture to the plasma discharge for a first predetermined time period such that transition metal oxide nanowires are formed; contacting the transition metal oxide nanowires with an acid solution such that an alkali metal ion is exchanged for a hydrogen ion on each of the transition metal oxide nanowires; and exposing the transition metal oxide nanowires to the plasma discharge for a second predetermined time period to thermally anneal the transition metal oxide nanowires. Transition metal oxide nanowires produced using the synthesis methods described herein are also provided.

  10. Recent advances of lanthanum-based perovskite oxides for catalysis

    SciTech Connect

    Zhu, Huiyuan; Zhang, Pengfei; Dai, Sheng

    2015-09-21

    There is a need to reduce the use of noble metal elements especially in the field of catalysis, where noble metals are ubiquitously applied. To this end, perovskite oxides, an important class of mixed oxide, have been attracting increasing attention for decades as potential replacements. Benefiting from the extraordinary tunability of their compositions and structures, perovskite oxides can be rationally tailored and equipped with targeted physical and chemical properties e.g. redox behavior, oxygen mobility, and ion conductivity for enhanced catalysis. Recently, the development of highly efficient perovskite oxide catalysts has been extensively studied. This review article summarizes the recent development of lanthanum-based perovskite oxides as advanced catalysts for both energy conversion applications and traditional heterogeneous reactions.

  11. Recent advances of lanthanum-based perovskite oxides for catalysis

    DOE PAGES

    Zhu, Huiyuan; Zhang, Pengfei; Dai, Sheng

    2015-09-21

    There is a need to reduce the use of noble metal elements especially in the field of catalysis, where noble metals are ubiquitously applied. To this end, perovskite oxides, an important class of mixed oxide, have been attracting increasing attention for decades as potential replacements. Benefiting from the extraordinary tunability of their compositions and structures, perovskite oxides can be rationally tailored and equipped with targeted physical and chemical properties e.g. redox behavior, oxygen mobility, and ion conductivity for enhanced catalysis. Recently, the development of highly efficient perovskite oxide catalysts has been extensively studied. This review article summarizes the recent developmentmore » of lanthanum-based perovskite oxides as advanced catalysts for both energy conversion applications and traditional heterogeneous reactions.« less

  12. Advanced analysis methods in particle physics

    SciTech Connect

    Bhat, Pushpalatha C.; /Fermilab

    2010-10-01

    Each generation of high energy physics experiments is grander in scale than the previous - more powerful, more complex and more demanding in terms of data handling and analysis. The spectacular performance of the Tevatron and the beginning of operations of the Large Hadron Collider, have placed us at the threshold of a new era in particle physics. The discovery of the Higgs boson or another agent of electroweak symmetry breaking and evidence of new physics may be just around the corner. The greatest challenge in these pursuits is to extract the extremely rare signals, if any, from huge backgrounds arising from known physics processes. The use of advanced analysis techniques is crucial in achieving this goal. In this review, I discuss the concepts of optimal analysis, some important advanced analysis methods and a few examples. The judicious use of these advanced methods should enable new discoveries and produce results with better precision, robustness and clarity.

  13. Cost estimating methods for advanced space systems

    NASA Technical Reports Server (NTRS)

    Cyr, Kelley

    1988-01-01

    The development of parametric cost estimating methods for advanced space systems in the conceptual design phase is discussed. The process of identifying variables which drive cost and the relationship between weight and cost are discussed. A theoretical model of cost is developed and tested using a historical data base of research and development projects.

  14. Advanced Launch System advanced development oxidizer turbopump program: Technical implementation plan

    NASA Technical Reports Server (NTRS)

    Ferlita, F.

    1989-01-01

    The Advanced Launch Systems (ALS) Advanced Development Oxidizer Turbopump Program has designed, fabricated and demonstrated a low cost, highly reliable oxidizer turbopump for the Space Transportation Engine that minimizes the recurring cost for the ALS engines. Pratt and Whitney's (P and W's) plan for integrating the analyses, testing, fabrication, and other program efforts is addressed. This plan offers a comprehensive description of the total effort required to design, fabricate, and test the ALS oxidizer turbopump. The proposed ALS oxidizer turbopump reduces turbopump costs over current designs by taking advantage of design simplicity and state-of-the-art materials and producibility features without compromising system reliability. This is accomplished by selecting turbopump operating conditions that are within known successful operating regions and by using proven manufacturing techniques.

  15. Apparatus and method for oxidizing organic materials

    DOEpatents

    Surma, Jeffrey E.; Bryan, Garry H.; Geeting, John G. H.; Butner, R. Scott

    1998-01-01

    The invention is a method and apparatus using high cerium concentration in the anolyte of an electrochemical cell to oxidize organic materials. The method and apparatus further use an ultrasonic mixer to enhance the oxidation rate of the organic material in the electrochemical cell.

  16. Apparatus and method for oxidizing organic materials

    SciTech Connect

    Surma, J.E.; Bryan, G.H.; Geeting, J.G.H.; Butner, R.S.

    1998-01-13

    The invention is a method and apparatus using high cerium concentration in the anolyte of an electrochemical cell to oxidize organic materials. The method and apparatus further use an ultrasonic mixer to enhance the oxidation rate of the organic material in the electrochemical cell. 6 figs.

  17. Impact of leachate composition on the advanced oxidation treatment.

    PubMed

    Oulego, Paula; Collado, Sergio; Laca, Adriana; Díaz, Mario

    2016-01-01

    Advanced oxidation processes (AOPs) are gaining importance as an alternative to the biological or physicochemical treatments for the management of leachates. In this work, it has been studied the effect of the characteristics of the leachate (content in humic acids, landfill age and degree of stabilization) on the wet oxidation process and final quality of the treated effluent. A high concentration of humic acids in the leachate had a positive effect on the COD removal because this fraction is more easily oxidizable. Additionally, it has been demonstrated that the simultaneous presence of humic acid and the intermediates generated during the oxidation process improved the degradation of this acid, since such intermediates are stronger initiators of free radicals than the humic acid itself. Similar values of COD removals (49% and 51%) and biodegradability indices (0.30 and 0.35) were observed, after 8 h of wet oxidation, for the stabilised leachate (biologically pretreated) and the raw one, respectively. Nevertheless, final colour removal was much higher for the stabilised leachate, achieving values up to 91%, whereas for the raw one only 56% removal was attained for the same reaction time. Besides, wet oxidation treatment was more efficient for the young leachate than for the old one, with final COD conversions of 60% and 37%, respectively. Eventually, a triangular "three-lump" kinetic model, which considered direct oxidation to CO2 and partial oxidation through intermediate compounds, was here proposed.

  18. Metal oxide composite dosimeter method and material

    DOEpatents

    Miller, Steven D.

    1998-01-01

    The present invention is a method of measuring a radiation dose wherein a radiation responsive material consisting essentially of metal oxide is first exposed to ionizing radiation. The metal oxide is then stimulating with light thereby causing the radiation responsive material to photoluminesce. Photons emitted from the metal oxide as a result of photoluminescence may be counted to provide a measure of the ionizing radiation.

  19. Editorial: Latest methods and advances in biotechnology.

    PubMed

    Lee, Sang Yup; Jungbauer, Alois

    2014-01-01

    The latest "Biotech Methods and Advances" special issue of Biotechnology Journal continues the BTJ tradition of featuring the latest breakthroughs in biotechnology. The special issue is edited by our Editors-in-Chief, Prof. Sang Yup Lee and Prof. Alois Jungbauer and covers a wide array of topics in biotechnology, including the perennial favorite workhorses of the biotech industry, Chinese hamster ovary (CHO) cell and Escherichia coli.

  20. Oxidation of alloys targeted for advanced steam turbines

    SciTech Connect

    Holcomb, G.R.; Covino, B.S., Jr.; Bullard, S.J.; Ziomek-Moroz, M.; Alman, D.E.

    2006-03-12

    Ultra supercritical (USC) power plants offer the promise of higher efficiencies and lower emissions. Current goals of the U.S. Department of Energy’s Advanced Power Systems Initiatives include coal generation at 60% efficiency, which would require steam temperatures of up to 760°C. This research examines the steamside oxidation of alloys for use in USC systems, with emphasis placed on applications in high- and intermediate-pressure turbines.

  1. Evaluation of advanced oxidation process for the treatment of groundwater

    SciTech Connect

    Garland, S.B. II ); Peyton, G.R. ); Rice, L.E. . Kansas City Div.)

    1990-01-01

    An advanced oxidation process utilizing ozone, ultraviolet radiation, and hydrogen peroxide was selected for the removal of chlorinated hydrocarbons, particularly trichlorethene and 1,2-dichlorethene, from groundwater underlying the US Department of Energy Kansas City Plant. Since the performance of this process for the removal of organics from groundwater is not well-documented, an evaluation was initiated to determine the performance of the treatment plant, document the operation and maintenance costs experience, and evaluate contaminant removal mechanisms. 11 refs., 3 figs.

  2. Simulation methods for advanced scientific computing

    SciTech Connect

    Booth, T.E.; Carlson, J.A.; Forster, R.A.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of the project was to create effective new algorithms for solving N-body problems by computer simulation. The authors concentrated on developing advanced classical and quantum Monte Carlo techniques. For simulations of phase transitions in classical systems, they produced a framework generalizing the famous Swendsen-Wang cluster algorithms for Ising and Potts models. For spin-glass-like problems, they demonstrated the effectiveness of an extension of the multicanonical method for the two-dimensional, random bond Ising model. For quantum mechanical systems, they generated a new method to compute the ground-state energy of systems of interacting electrons. They also improved methods to compute excited states when the diffusion quantum Monte Carlo method is used and to compute longer time dynamics when the stationary phase quantum Monte Carlo method is used.

  3. Ammonia release method for depositing metal oxides

    DOEpatents

    Silver, G.L.; Martin, F.S.

    1994-12-13

    A method is described for depositing metal oxides on substrates which is indifferent to the electrochemical properties of the substrates and which comprises forming ammine complexes containing metal ions and thereafter effecting removal of ammonia from the ammine complexes so as to permit slow precipitation and deposition of metal oxide on the substrates. 1 figure.

  4. Ammonia release method for depositing metal oxides

    DOEpatents

    Silver, Gary L.; Martin, Frank S.

    1994-12-13

    A method of depositing metal oxides on substrates which is indifferent to the electrochemical properties of the substrates and which comprises forming ammine complexes containing metal ions and thereafter effecting removal of ammonia from the ammine complexes so as to permit slow precipitation and deposition of metal oxide on the substrates.

  5. Ammonia release method for depositing metal oxides

    SciTech Connect

    Silver, G.L.; Martin, F.S.

    1993-12-31

    A method of depositing metal oxides on substrates which is indifferent to the electrochemical properties of the substrates and which comprises forming ammine complexes containing metal ions and thereafter effecting removal of ammonia from the ammine complexes so as to permit slow precipitation and deposition of metal oxide on the substrates.

  6. Alloys for advanced steam turbines--Oxidation behavior

    SciTech Connect

    Holcomb, G.R.

    2007-10-01

    Advanced or ultra supercritical (USC) steam power plants offer the promise of higher efficiencies and lower emissions. Current goals of the U.S. Department of Energy (DOE) include power generation from coal at 60% efficiency, which would require steam temperatures of up to 760°C. Current research on the oxidation of candidate materials for advanced steam turbines is presented with a focus on a methodology for estimating chromium evaporation rates from protective chromia scales. The high velocities and pressures of advanced steam turbines lead to evaporation predictions as high as 5 × 10-8 kg m-2s-1 of CrO2(OH)2(g) at 760°C and 34.5 MPa. This is equivalent to 0.077 mm per year of solid Cr loss.

  7. Advanced Bayesian Method for Planetary Surface Navigation

    NASA Technical Reports Server (NTRS)

    Center, Julian

    2015-01-01

    Autonomous Exploration, Inc., has developed an advanced Bayesian statistical inference method that leverages current computing technology to produce a highly accurate surface navigation system. The method combines dense stereo vision and high-speed optical flow to implement visual odometry (VO) to track faster rover movements. The Bayesian VO technique improves performance by using all image information rather than corner features only. The method determines what can be learned from each image pixel and weighs the information accordingly. This capability improves performance in shadowed areas that yield only low-contrast images. The error characteristics of the visual processing are complementary to those of a low-cost inertial measurement unit (IMU), so the combination of the two capabilities provides highly accurate navigation. The method increases NASA mission productivity by enabling faster rover speed and accuracy. On Earth, the technology will permit operation of robots and autonomous vehicles in areas where the Global Positioning System (GPS) is degraded or unavailable.

  8. Recent advances in analytical methods for mycotoxins.

    PubMed

    Gilbert, J

    1993-01-01

    Recent advances in analytical methods are reviewed using the examples of aflatoxins and trichothecene mycotoxins. The most dramatic advances are seen as being those based on immunological principles utilized for aflatoxins to produce simple screening methods and for rapid specific clean-up. The possibilities of automation using immunoaffinity columns is described. In contrast for the trichothecenes immunological methods have not had the same general impact. Post-column derivatization using bromine or iodine to enhance fluorescence for HPLC detection of aflatoxins has become widely employed and there are similar possibilities for improved HPLC detection for trichothecenes using electrochemical or trichothecene-specific post-column reactions. There have been improvements in the use of more rapid and specific clean-up methods for trichothecenes, whilst HPLC and GC remain equally favoured for the end-determination. More sophisticated instrumental techniques such as mass spectrometry (LC/MS, MS/MS) and supercritical fluid chromatography (SFC/MS) have been demonstrated to have potential for application to mycotoxin analysis, but have not as yet made much general impact.

  9. Nitric oxide methods in seed biology.

    PubMed

    Bethke, Paul C; Libourel, Igor G L; Vitecek, Jan; Jones, Russell L

    2011-01-01

    The ubiquitous signaling molecule nitric oxide (NO) plays an important role in seed biology. Experiments with this biologically important gas require special provisions because NO in aerobic environments is readily converted into other oxides of nitrogen. In this chapter, we describe methods for the application of NO as a gas, and through the use of NO-donor compounds. We included information on the removal or reduction of NO with NO scavengers. Methods for detecting NO using NO-reactive fluorescent probes, and an apparatus incorporating an oxidizer column are also described.

  10. Method for producing metal oxide nanoparticles

    DOEpatents

    Phillips, Jonathan; Mendoza, Daniel; Chen, Chun-Ku

    2008-04-15

    Method for producing metal oxide nanoparticles. The method includes generating an aerosol of solid metallic microparticles, generating plasma with a plasma hot zone at a temperature sufficiently high to vaporize the microparticles into metal vapor, and directing the aerosol into the hot zone of the plasma. The microparticles vaporize in the hot zone into metal vapor. The metal vapor is directed away from the hot zone and into the cooler plasma afterglow where it oxidizes, cools and condenses to form solid metal oxide nanoparticles.

  11. Advanced oxidation of alkylphenol ethoxylates in aqueous systems.

    PubMed

    Nagarnaik, Pranav M; Boulanger, Bryan

    2011-10-01

    Alkylphenols and alkylphenol ethoxylates are ubiquitous wastewater contaminants. In this study the oxidation of nonylphenol ethoxylates (NPEO) and octylphenol ethoxylates (OPEO) by oxidant systems generating hydroxide radicals was evaluated. The reaction of each oxidant with a technical mixture of NPEO (Tergitol™) and OPEO (Triton X-100™) in ultrapure laboratory water and four aqueous environmental matrices was carried out in order to develop an understanding of reaction kinetics. The oxidation of APEOs was evaluated by hydroxyl radical generated by (1) hydrogen peroxide in the presence of ultraviolet light, (2) Fenton's reagent, and (3) a photo-Fenton's process. The second order kinetic rate constant for both NPEO and OPEO with hydroxyl radical was calculated to be 1.1×10¹⁰ M⁻¹ s⁻¹. The efficacy of the AOPs within an aqueous environmental matrix was dependent on the rate of formation of hydroxyl radical and the scavenging capacity of the matrix. A model based on the hydroxyl radical formation, scavenging capacity and the kinetic rate constant of target APEO was developed from the existing literature and applied to predict the concentration of APEOs in solution during advanced oxidation in different aqueous environmental matrices. PMID:21784502

  12. Advanced Analysis Methods in High Energy Physics

    SciTech Connect

    Pushpalatha C. Bhat

    2001-10-03

    During the coming decade, high energy physics experiments at the Fermilab Tevatron and around the globe will use very sophisticated equipment to record unprecedented amounts of data in the hope of making major discoveries that may unravel some of Nature's deepest mysteries. The discovery of the Higgs boson and signals of new physics may be around the corner. The use of advanced analysis techniques will be crucial in achieving these goals. The author discusses some of the novel methods of analysis that could prove to be particularly valuable for finding evidence of any new physics, for improving precision measurements and for exploring parameter spaces of theoretical models.

  13. Advanced oxidation protein products (AOPP) for monitoring oxidative stress in critically ill patients: a simple, fast and inexpensive automated technique.

    PubMed

    Selmeci, László; Seres, Leila; Antal, Magda; Lukács, Júlia; Regöly-Mérei, Andrea; Acsády, György

    2005-01-01

    Oxidative stress is known to be involved in many human pathological processes. Although there are numerous methods available for the assessment of oxidative stress, most of them are still not easily applicable in a routine clinical laboratory due to the complex methodology and/or lack of automation. In research into human oxidative stress, the simplification and automation of techniques represent a key issue from a laboratory point of view at present. In 1996 a novel oxidative stress biomarker, referred to as advanced oxidation protein products (AOPP), was detected in the plasma of chronic uremic patients. Here we describe in detail an automated version of the originally published microplate-based technique that we adapted for a Cobas Mira Plus clinical chemistry analyzer. AOPP reference values were measured in plasma samples from 266 apparently healthy volunteers (university students; 81 male and 185 female subjects) with a mean age of 21.3 years (range 18-33). Over a period of 18 months we determined AOPP concentrations in more than 300 patients in our department. Our experiences appear to demonstrate that this technique is especially suitable for monitoring oxidative stress in critically ill patients (sepsis, reperfusion injury, heart failure) even at daily intervals, since AOPP exhibited rapid responses in both directions. We believe that the well-established relationship between AOPP response and induced damage makes this simple, fast and inexpensive automated technique applicable in daily routine laboratory practice for assessing and monitoring oxidative stress in critically ill or other patients.

  14. Method for making monolithic metal oxide aerogels

    DOEpatents

    Droege, M.W.; Coronado, P.R.; Hair, L.M.

    1995-03-07

    Transparent, monolithic metal oxide aerogels of varying densities are produced using a method in which a metal alkoxide solution and a catalyst solution are prepared separately and reacted. The resulting hydrolyzed-condensed colloidal solution is gelled, and the wet gel is contained within a sealed, but gas permeable, containment vessel during supercritical extraction of the solvent. The present invention is especially advantageous for making metal oxides other than silica that are prone to forming opaque, cracked aerogels. 6 figs.

  15. Mixed oxide nanoparticles and method of making

    DOEpatents

    Lauf, Robert J.; Phelps, Tommy J.; Zhang, Chuanlun; Roh, Yul

    2002-09-03

    Methods and apparatus for producing mixed oxide nanoparticulates are disclosed. Selected thermophilic bacteria cultured with suitable reducible metals in the presence of an electron donor may be cultured under conditions that reduce at least one metal to form a doped crystal or mixed oxide composition. The bacteria will form nanoparticles outside the cell, allowing easy recovery. Selection of metals depends on the redox potentials of the reducing agents added to the culture. Typically hydrogen or glucose are used as electron donors.

  16. Method for making monolithic metal oxide aerogels

    DOEpatents

    Droege, Michael W.; Coronado, Paul R.; Hair, Lucy M.

    1995-01-01

    Transparent, monolithic metal oxide aerogels of varying densities are produced using a method in which a metal alkoxide solution and a catalyst solution are prepared separately and reacted. The resulting hydrolyzed-condensed colloidal solution is gelled, and the wet gel is contained within a sealed, but gas permeable, containment vessel during supercritical extraction of the solvent. The present invention is especially advantageous for making metal oxides other than silica that are prone to forming opaque, cracked aerogels.

  17. Advances in plant gene silencing methods.

    PubMed

    Pandey, Prachi; Senthil-Kumar, Muthappa; Mysore, Kirankumar S

    2015-01-01

    Understanding molecular mechanisms of transcriptional and posttranscriptional gene silencing pathways in plants over the past decades has led to development of tools and methods for silencing a target gene in various plant species. In this review chapter, both the recent understanding of molecular basis of gene silencing pathways and advances in various widely used gene silencing methods are compiled. We also discuss the salient features of the different methods like RNA interference (RNAi) and virus-induced gene silencing (VIGS) and highlight their advantages and disadvantages. Gene silencing technology is constantly progressing as reflected by rapidly emerging new methods. A succinct discussion on the recently developed methods like microRNA-mediated virus-induced gene silencing (MIR-VIGS) and microRNA-induced gene silencing (MIGS) is also provided. One major bottleneck in gene silencing approaches has been the associated off-target silencing. The other hurdle has been the lack of a universal approach that can be applied to all plants. For example, we face hurdles like incompatibility of VIGS vectors with the host and inability to use MIGS for plant species which are not easily transformable. However, the overwhelming research in this direction reflects the scope for overcoming the short comings of gene silencing technology.

  18. [Research advances on anaerobic ferrous-oxidizing microorganisms].

    PubMed

    Zhang, Meng; Zheng, Ping; Ji, Jun-yuan

    2013-08-01

    Anaerobic ferrous-oxidizing microorganisms (AFOM) are one of the important discoveries in microbiology, geology and environmental science. The study of AFOM is of significance to make clear the banded iron formations (BIFs), promote the biogeochemical cycles of iron, nitrogen and carbon, enrich the microbiological content, develop new biotechnologies for anaerobic iron oxidation, and explore the ancient earth environment and extraterrestrial life. This paper summarized the research advances on AFOM, introduced the habitats of AFOM, discussed the biodiversity and the nutritive and metabolic characteristics of AFOM, and assessed the potential functions of AFOM. An outlook was made on the future researches of new species AFOM, their microbial metabolism mechanisms, and their development and applications. PMID:24380362

  19. Recent advances (2010-2015) in studies of cerium oxide nanoparticles' health effects.

    PubMed

    Li, Yan; Li, Peng; Yu, Hua; Bian, Ying

    2016-06-01

    Cerium oxide nanoparticles, widespread applied in our life, have attracted much concern for their human health effects. However, most of the works addressing cerium oxide nanoparticles toxicity have only used in vitro models or in vivo intratracheal instillation methods. The toxicity studies have varied results and not all are conclusive. The information about risk assessments derived from epidemiology studies is severely lacking. The knowledge of occupational safety and health (OSH) for exposed workers is very little. Thus this review focuses on recent advances in studies of toxicokinetics, antioxidant activity and toxicity. Additionally, aim to extend previous health effects assessments of cerium oxide nanoparticles, we summarize the epidemiology studies of engineered cerium oxide nanoparticles used as automotive diesel fuel additive, aerosol particulate matter in air pollution, other industrial ultrafine and nanoparticles (e.g., fumes particles generated in welding and flame cutting processes). PMID:27088851

  20. Evaluation of Resin Dissolution Using an Advanced Oxidation Process - 13241

    SciTech Connect

    Goulart de Araujo, Leandro; Vicente de Padua Ferreira, Rafael; Takehiro Marumo, Julio; Passos Piveli, Roque; Campos, Fabio

    2013-07-01

    The ion-exchange resin is widely used in nuclear reactors, in cooling water purification and removing radioactive elements. Because of the long periods of time inside the reactor system, the resin becomes radioactive. When the useful life of them is over, its re-utilization becomes inappropriate, and for this reason, the resin is considered radioactive waste. The most common method of treatment is the immobilization of spent ion exchange resin in cement in order to form a solid monolithic matrix, which reduces the radionuclides release into the environment. However, the characteristic of contraction and expansion of the resin limits its incorporation in 10%, resulting in high cost in its direct immobilization. Therefore, it is recommended the utilization of a pre-treatment, capable of reducing the volume and degrading the resin, which would increase the load capacity in the immobilization. This work aims to develop a method of degradation of ion spent resins from the nuclear research reactor of Nuclear and Energy Research Institute (IPEN/CNEN-SP), Brazil, using the Advanced Oxidative Process (AOP) with Fenton's reagent (hydrogen peroxide and ferrous sulphate as catalyst). The resin evaluated was a mixture of cationic (IR 120P) and anionic (IRA 410) resins. The reactions were conducted by varying the concentration of the catalyst (25, 50, 100 e 150 mM) and the volume of the hydrogen peroxide, at three different temperatures, 50, 60 and 70 deg. C. The time of reaction was three hours. Total organic carbon content was determined periodically in order to evaluate the degradation as a function of time. The concentration of 50 mM of catalyst was the most effective in degrading approximately 99%, using up to 330 mL of hydrogen peroxide. The most effective temperature was about 60 deg. C, because of the decomposition of hydrogen peroxide in higher temperatures. TOC content was influenced by the concentration of the catalyst, interfering in the beginning of the degradation

  1. Advanced fault diagnosis methods in molecular networks.

    PubMed

    Habibi, Iman; Emamian, Effat S; Abdi, Ali

    2014-01-01

    Analysis of the failure of cell signaling networks is an important topic in systems biology and has applications in target discovery and drug development. In this paper, some advanced methods for fault diagnosis in signaling networks are developed and then applied to a caspase network and an SHP2 network. The goal is to understand how, and to what extent, the dysfunction of molecules in a network contributes to the failure of the entire network. Network dysfunction (failure) is defined as failure to produce the expected outputs in response to the input signals. Vulnerability level of a molecule is defined as the probability of the network failure, when the molecule is dysfunctional. In this study, a method to calculate the vulnerability level of single molecules for different combinations of input signals is developed. Furthermore, a more complex yet biologically meaningful method for calculating the multi-fault vulnerability levels is suggested, in which two or more molecules are simultaneously dysfunctional. Finally, a method is developed for fault diagnosis of networks based on a ternary logic model, which considers three activity levels for a molecule instead of the previously published binary logic model, and provides equations for the vulnerabilities of molecules in a ternary framework. Multi-fault analysis shows that the pairs of molecules with high vulnerability typically include a highly vulnerable molecule identified by the single fault analysis. The ternary fault analysis for the caspase network shows that predictions obtained using the more complex ternary model are about the same as the predictions of the simpler binary approach. This study suggests that by increasing the number of activity levels the complexity of the model grows; however, the predictive power of the ternary model does not appear to be increased proportionally.

  2. Advanced reactor physics methods for heterogeneous reactor cores

    NASA Astrophysics Data System (ADS)

    Thompson, Steven A.

    To maintain the economic viability of nuclear power the industry has begun to emphasize maximizing the efficiency and output of existing nuclear power plants by using longer fuel cycles, stretch power uprates, shorter outage lengths, mixed-oxide (MOX) fuel and more aggressive operating strategies. In order to accommodate these changes, while still satisfying the peaking factor and power envelope requirements necessary to maintain safe operation, more complexity in commercial core designs have been implemented, such as an increase in the number of sub-batches and an increase in the use of both discrete and integral burnable poisons. A consequence of the increased complexity of core designs, as well as the use of MOX fuel, is an increase in the neutronic heterogeneity of the core. Such heterogeneous cores introduce challenges for the current methods that are used for reactor analysis. New methods must be developed to address these deficiencies while still maintaining the computational efficiency of existing reactor analysis methods. In this thesis, advanced core design methodologies are developed to be able to adequately analyze the highly heterogeneous core designs which are currently in use in commercial power reactors. These methodological improvements are being pursued with the goal of not sacrificing the computational efficiency which core designers require. More specifically, the PSU nodal code NEM is being updated to include an SP3 solution option, an advanced transverse leakage option, and a semi-analytical NEM solution option.

  3. OXIDATIVE METHOD OF SEPARATING PLUTONIUM FROM NEPTUNIUM

    DOEpatents

    Beaufait, L.J. Jr.

    1958-06-10

    A method is described of separating neptunium from plutonium in an aqueous solution containing neptunium and plutonium in valence states not greater than +4. This may be accomplished by contacting the solution with dichromate ions, thus oxidizing the neptunium to a valence state greater than +4 without oxidizing any substantial amount of plutonium, and then forming a carrier precipitate which carries the plutonium from solution, leaving the neptunium behind. A preferred embodiment of this invention covers the use of lanthanum fluoride as the carrier precipitate.

  4. Oxidation behavior of plasma sintered beryllium-titanium intermetallic compounds as an advanced neutron multiplier

    NASA Astrophysics Data System (ADS)

    Kim, Jae-Hwan; Nakamichi, Masaru

    2013-07-01

    Beryllium intermetallic compounds (beryllides) such as Be12Ti are very promising candidates for advanced neutron multiplier materials in a demonstration fusion power reactor (DEMO). However, beryllides are too brittle to be fabricated either into pebble-type or rod-type shapes via conventional methods (i.e. arc melting and hot isostatic pressing). We have proposed a plasma sintering technique as a new method for beryllide fabrication, and our studies on the properties of plasma sintered beryllides are ongoing. In the present work, the oxidation properties of plasma sintered beryllides were investigated at 1273 K for 24 h in a dry air atmosphere to evaluate the high temperature properties of this material. Thermal gravimetry measurements indicate that specimens with larger fractions of Be12Ti phase corresponding to samples that have been sintered for longer time periods, exhibit superior oxidation properties. Our evaluation of the oxidation behavior of each phase in our beryllide samples is as follows: Be12Ti and Be17Ti2 both have good oxidation resistance, owing to the formation of dense and protective scales, while the Be and Be2Ti phases are mainly responsible for thermal-gravimetry (TG) weight gains, which is indicative of severe oxidation. We attribute the degradation in oxidation resistance specifically to Be2Ti that transforms into TiO2, and also find this phase to be the cause of deterioration in the mechanical properties of samples, owing to cracks near Be2Ti phase conglomerates.

  5. Advanced continuous cultivation methods for systems microbiology.

    PubMed

    Adamberg, Kaarel; Valgepea, Kaspar; Vilu, Raivo

    2015-09-01

    Increasing the throughput of systems biology-based experimental characterization of in silico-designed strains has great potential for accelerating the development of cell factories. For this, analysis of metabolism in the steady state is essential as only this enables the unequivocal definition of the physiological state of cells, which is needed for the complete description and in silico reconstruction of their phenotypes. In this review, we show that for a systems microbiology approach, high-resolution characterization of metabolism in the steady state--growth space analysis (GSA)--can be achieved by using advanced continuous cultivation methods termed changestats. In changestats, an environmental parameter is continuously changed at a constant rate within one experiment whilst maintaining cells in the physiological steady state similar to chemostats. This increases the resolution and throughput of GSA compared with chemostats, and, moreover, enables following of the dynamics of metabolism and detection of metabolic switch-points and optimal growth conditions. We also describe the concept, challenge and necessary criteria of the systematic analysis of steady-state metabolism. Finally, we propose that such systematic characterization of the steady-state growth space of cells using changestats has value not only for fundamental studies of metabolism, but also for systems biology-based metabolic engineering of cell factories.

  6. Advanced electromagnetic methods for aerospace vehicles

    NASA Astrophysics Data System (ADS)

    Balanis, Constantine A.; Sun, Weimin; El-Sharawy, El-Budawy; Aberle, James T.; Birtcher, Craig R.; Peng, Jian; Tirkas, Panayiotis A.; Kokotoff, David; Zavosh, Frank

    1993-06-01

    The Advanced Helicopter Electromagnetics (AHE) Industrial Associates Program has continuously progressed with its research effort focused on subjects identified and recommended by the Advisory Task Force of the program. The research activities in this reporting period have been steered toward practical helicopter electromagnetic problems, such as HF antenna problems and antenna efficiencies, recommended by the AHE members at the annual conference held at Arizona State University on 28-29 Oct. 1992 and the last biannual meeting held at the Boeing Helicopter on 19-20 May 1993. The main topics addressed include the following: Composite Materials and Antenna Technology. The research work on each topic is closely tied with the AHE Consortium members' interests. Significant progress in each subject is reported. Special attention in the area of Composite Materials has been given to the following: modeling of material discontinuity and their effects on towel-bar antenna patterns; guidelines for composite material modeling by using the Green's function approach in the NEC code; measurements of towel-bar antennas grounded with a partially material-coated plate; development of 3-D volume mesh generator for modeling thick and volumetric dielectrics by using FD-TD method; FDTD modeling of horn antennas with composite E-plane walls; and antenna efficiency analysis for a horn antenna loaded with composite dielectric materials.

  7. Advanced electromagnetic methods for aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Balanis, Constantine A.; Sun, Weimin; El-Sharawy, El-Budawy; Aberle, James T.; Birtcher, Craig R.; Peng, Jian; Tirkas, Panayiotis A.; Kokotoff, David; Zavosh, Frank

    1993-01-01

    The Advanced Helicopter Electromagnetics (AHE) Industrial Associates Program has continuously progressed with its research effort focused on subjects identified and recommended by the Advisory Task Force of the program. The research activities in this reporting period have been steered toward practical helicopter electromagnetic problems, such as HF antenna problems and antenna efficiencies, recommended by the AHE members at the annual conference held at Arizona State University on 28-29 Oct. 1992 and the last biannual meeting held at the Boeing Helicopter on 19-20 May 1993. The main topics addressed include the following: Composite Materials and Antenna Technology. The research work on each topic is closely tied with the AHE Consortium members' interests. Significant progress in each subject is reported. Special attention in the area of Composite Materials has been given to the following: modeling of material discontinuity and their effects on towel-bar antenna patterns; guidelines for composite material modeling by using the Green's function approach in the NEC code; measurements of towel-bar antennas grounded with a partially material-coated plate; development of 3-D volume mesh generator for modeling thick and volumetric dielectrics by using FD-TD method; FDTD modeling of horn antennas with composite E-plane walls; and antenna efficiency analysis for a horn antenna loaded with composite dielectric materials.

  8. Advanced electromagnetic methods for aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Balanis, Constantine A.; Sun, Weimin; El-Sharawy, El-Budawy; Aberle, James T.; Birtcher, Craig R.; Peng, Jian; Tirkas, Panayiotis A.; Andrew, William V.; Kokotoff, David; Zavosh, Frank

    1993-01-01

    The Advanced Helicopter Electromagnetics (AHE) Industrial Associates Program has fruitfully completed its fourth year. Under the support of the AHE members and the joint effort of the research team, new and significant progress has been achieved in the year. Following the recommendations by the Advisory Task Force, the research effort is placed on more practical helicopter electromagnetic problems, such as HF antennas, composite materials, and antenna efficiencies. In this annual report, the main topics to be addressed include composite materials and antenna technology. The research work on each topic has been driven by the AHE consortium members' interests and needs. The remarkable achievements and progresses in each subject is reported respectively in individual sections of the report. The work in the area of composite materials includes: modeling of low conductivity composite materials by using Green's function approach; guidelines for composite material modeling by using the Green's function approach in the NEC code; development of 3-D volume mesh generator for modeling thick and volumetric dielectrics by using FD-TD method; modeling antenna elements mounted on a composite Comanche tail stabilizer; and antenna pattern control and efficiency estimate for a horn antenna loaded with composite dielectric materials.

  9. Advanced oxidation to treat gasoline-contaminated groundwater

    SciTech Connect

    Singh, R.; Medlar, S.J. )

    1992-04-01

    For 10 to 20 years, an undetermined amount of gasoline leaked from a petroleum terminal at a site in New York State and caused groundwater contamination. Benzene, toluene, ethylbenzene, and xylenes were detected in concentrations of up to 90mg/L in some areas, and high levels of iron and lead were also observed. After discovery, recovery wells were installed to pump the pure product out of the ground. To date, more than 1500m[sup 3] (400,000 gal) of gasoline have been recovered. Wells were also installed to intercept the contaminant plume to prevent its migration. An air stripper with vapor-phase carbon was put on line as an immediate response measure to treat the intercepted groundwater. A site remediation plan was proposed to pump the gasoline-contaminated groundwater, treat it to remove both the metals and toxic organic contaminants, and then recharge it to the aquifer. One of the technologies proposed for the treatability study was the advanced oxidation (AO) process which uses ozone and hydrogen peroxide to destroy organic chemicals. This process involves the formation of free radicals by ozone decomposition; the hydroxyl radical concentration increases and contaminant oxidation and destruction are promoted.

  10. Oxidative Stress in Aging: Advances in Proteomic Approaches

    PubMed Central

    Ortuño-Sahagún, Daniel; Pallàs, Mercè; Rojas-Mayorquín, Argelia E.

    2014-01-01

    Aging is a gradual, complex process in which cells, tissues, organs, and the whole organism itself deteriorate in a progressive and irreversible manner that, in the majority of cases, implies pathological conditions that affect the individual's Quality of Life (QOL). Although extensive research efforts in recent years have been made, the anticipation of aging and prophylactic or treatment strategies continue to experience major limitations. In this review, the focus is essentially on the compilation of the advances generated by cellular expression profile analysis through proteomics studies (two-dimensional [2D] electrophoresis and mass spectrometry [MS]), which are currently used as an integral approach to study the aging process. Additionally, the relevance of the oxidative stress factors is discussed. Emphasis is placed on postmitotic tissues, such as neuronal, muscular, and red blood cells, which appear to be those most frequently studied with respect to aging. Additionally, models for the study of aging are discussed in a number of organisms, such as Caenorhabditis elegans, senescence-accelerated probe-8 mice (SAMP8), naked mole-rat (Heterocephalus glaber), and the beagle canine. Proteomic studies in specific tissues and organisms have revealed the extensive involvement of reactive oxygen species (ROS) and oxidative stress in aging. PMID:24688629

  11. Oxidative stress in aging: advances in proteomic approaches.

    PubMed

    Ortuño-Sahagún, Daniel; Pallàs, Mercè; Rojas-Mayorquín, Argelia E

    2014-01-01

    Aging is a gradual, complex process in which cells, tissues, organs, and the whole organism itself deteriorate in a progressive and irreversible manner that, in the majority of cases, implies pathological conditions that affect the individual's Quality of Life (QOL). Although extensive research efforts in recent years have been made, the anticipation of aging and prophylactic or treatment strategies continue to experience major limitations. In this review, the focus is essentially on the compilation of the advances generated by cellular expression profile analysis through proteomics studies (two-dimensional [2D] electrophoresis and mass spectrometry [MS]), which are currently used as an integral approach to study the aging process. Additionally, the relevance of the oxidative stress factors is discussed. Emphasis is placed on postmitotic tissues, such as neuronal, muscular, and red blood cells, which appear to be those most frequently studied with respect to aging. Additionally, models for the study of aging are discussed in a number of organisms, such as Caenorhabditis elegans, senescence-accelerated probe-8 mice (SAMP8), naked mole-rat (Heterocephalus glaber), and the beagle canine. Proteomic studies in specific tissues and organisms have revealed the extensive involvement of reactive oxygen species (ROS) and oxidative stress in aging.

  12. Advanced oxidation processes for degradation of 2,4-dichlo- and 2,4-dimethylphenol

    SciTech Connect

    Trapido, M.; Veressinina, Y.; Munter, R.

    1998-08-01

    The efficiency of different advanced oxidation processes for degradation of two phenols, 2,4-dimethylphenol (2,4-DMP) and 2,4-dichlorophenol (2,4-DCP), has been under study. Advanced oxidation processes, especially the Fe{sup 2+}/H{sub 2}O{sub 2}/ultraviolet (UV) system, were found to be effective in decomposing phenols and chlorophenols. The degradation rate for 2,4-DCP followed the order, H{sub 2}O{sub 2}/Fe{sup 2+}/UV > H{sub 2}O{sub 2}/Fe{sup 2+} > O{sub 3}/ultrasound (US) > O{sub 3} {ge} O{sub 3}/UV > UV/H{sub 2}O{sub 2} {ge} US > UV. The corresponding order for 2,4-DMP was H{sub 2}O{sub 2}/Fe{sup 2+}/UV > O{sub 3}/US > O{sub 3} {ge} O{sub 3}/UV > H{sub 2}O{sub 2}/Fe{sup 2+} > US {ge} UV/H{sub 2}O{sub 2} > UV. Therefore, the chemical treatment, especially advanced oxidation processes, may be an alternative method for destruction of phenols and purification of wastewaters containing phenolic compounds.

  13. Gas-phase advanced oxidation for effective, efficient in situ control of pollution.

    PubMed

    Johnson, Matthew S; Nilsson, Elna J K; Svensson, Erik A; Langer, Sarka

    2014-01-01

    In this article, gas-phase advanced oxidation, a new method for pollution control building on the photo-oxidation and particle formation chemistry occurring in the atmosphere, is introduced and characterized. The process uses ozone and UV-C light to produce in situ radicals to oxidize pollution, generating particles that are removed by a filter; ozone is removed using a MnO2 honeycomb catalyst. This combination of in situ processes removes a wide range of pollutants with a comparatively low specific energy input. Two proof-of-concept devices were built to test and optimize the process. The laboratory prototype was built of standard ventilation duct and could treat up to 850 m(3)/h. A portable continuous-flow prototype built in an aluminum flight case was able to treat 46 m(3)/h. Removal efficiencies of >95% were observed for propane, cyclohexane, benzene, isoprene, aerosol particle mass, and ozone for concentrations in the range of 0.4-6 ppm and exposure times up to 0.5 min. The laboratory prototype generated a OH(•) concentration derived from propane reaction of (2.5 ± 0.3) × 10(10) cm(-3) at a specific energy input of 3 kJ/m(3), and the portable device generated (4.6 ± 0.4) × 10(9) cm(-3) at 10 kJ/m(3). Based on these results, in situ gas-phase advanced oxidation is a viable control strategy for most volatile organic compounds, specifically those with a OH(•) reaction rate higher than ca. 5 × 10(-13) cm(3)/s. Gas-phase advanced oxidation is able to remove compounds that react with OH and to control ozone and total particulate mass. Secondary pollution including formaldehyde and ultrafine particles might be generated, depending on the composition of the primary pollution.

  14. Treatment of real industrial wastewater using the combined approach of advanced oxidation followed by aerobic oxidation.

    PubMed

    Ramteke, Lokeshkumar P; Gogate, Parag R

    2016-05-01

    Fenton oxidation and ultrasound-based pretreatment have been applied to improve the treatment of real industrial wastewater based on the use of biological oxidation. The effect of operating parameters such as Fe(2+) loading, contact time, initial pH, and hydrogen peroxide loading on the extent of chemical oxygen demand (COD) reduction and change in biochemical oxygen demand (BOD5)/COD ratio has been investigated. The optimum operating conditions established for the pretreatment were initial pH of 3.0, Fe(2+) loading of 2.0, and 2.5 g L(-1) for the US/Fenton/stirring and Fenton approach, respectively, and temperature of 25 °C with initial H2O2 loading of 1.5 g L(-1). The use of pretreatment resulted in a significant increase in the BOD5/COD ratio confirming the production of easily digestible intermediates. The effect of the type of sludge in the aerobic biodegradation was also investigated based on the use of primary activated sludge (PAS), modified activated sludge (MAS), and activated sludge (AS). Enhanced removal of the pollutants as well as higher biomass yield was observed for MAS as compared to PAS and AS. The use of US/Fenton/stirring pretreatment under the optimized conditions followed by biological oxidation using MAS resulted in maximum COD removal at 97.9 %. The required hydraulic retention time for the combined oxidation system was also significantly lower as compared to only biological oxidation operation. Kinetic studies revealed that the reduction in the COD followed a first-order kinetic model for advanced oxidation and pseudo first-order model for biodegradation. The study clearly established the utility of the combined technology for the effective treatment of real industrial wastewater.

  15. Iron(3) oxide-based nanoparticles as catalysts in advanced organic aqueous oxidation.

    PubMed

    Zelmanov, Grigory; Semiat, Raphael

    2008-01-01

    Water contaminated with dissolved organic matter is an important issue to resolve for all-purpose uses. The catalytic behavior of iron-based nanocatalysts was investigated for the treatment of contaminated water in the advanced chemical oxidation process. In this study, typical organic contaminants, such as ethylene glycol and phenol, were chosen to simulate common contaminants. It was shown that the two substances are efficiently destroyed by the Fenton-like reaction using iron(3) oxide-based nanocatalysts in the presence of hydrogen peroxide without the need for UV or visible radiation sources at room temperature. A strong effect of nanocatalyst concentration on reaction rate was shown. The kinetic reaction was found and the reaction rate coefficient k was calculated.

  16. Oxidative Stress to the Cornea, Changes in Corneal Optical Properties, and Advances in Treatment of Corneal Oxidative Injuries

    PubMed Central

    Cejka, Cestmir; Cejkova, Jitka

    2015-01-01

    Oxidative stress is involved in many ocular diseases and injuries. The imbalance between oxidants and antioxidants in favour of oxidants (oxidative stress) leads to the damage and may be highly involved in ocular aging processes. The anterior eye segment and mainly the cornea are directly exposed to noxae of external environment, such as air pollution, radiation, cigarette smoke, vapors or gases from household cleaning products, chemical burns from splashes of industrial chemicals, and danger from potential oxidative damage evoked by them. Oxidative stress may initiate or develop ocular injury resulting in decreased visual acuity or even vision loss. The role of oxidative stress in the pathogenesis of ocular diseases with particular attention to oxidative stress in the cornea and changes in corneal optical properties are discussed. Advances in the treatment of corneal oxidative injuries or diseases are shown. PMID:25861412

  17. Oxidative stress to the cornea, changes in corneal optical properties, and advances in treatment of corneal oxidative injuries.

    PubMed

    Cejka, Cestmir; Cejkova, Jitka

    2015-01-01

    Oxidative stress is involved in many ocular diseases and injuries. The imbalance between oxidants and antioxidants in favour of oxidants (oxidative stress) leads to the damage and may be highly involved in ocular aging processes. The anterior eye segment and mainly the cornea are directly exposed to noxae of external environment, such as air pollution, radiation, cigarette smoke, vapors or gases from household cleaning products, chemical burns from splashes of industrial chemicals, and danger from potential oxidative damage evoked by them. Oxidative stress may initiate or develop ocular injury resulting in decreased visual acuity or even vision loss. The role of oxidative stress in the pathogenesis of ocular diseases with particular attention to oxidative stress in the cornea and changes in corneal optical properties are discussed. Advances in the treatment of corneal oxidative injuries or diseases are shown. PMID:25861412

  18. Why Video? How Technology Advances Method

    ERIC Educational Resources Information Center

    Downing, Martin J., Jr.

    2008-01-01

    This paper reports on the use of video to enhance qualitative research. Advances in technology have improved our ability to capture lived experiences through visual means. I reflect on my previous work with individuals living with HIV/AIDS, the results of which are described in another paper, to evaluate the effectiveness of video as a medium that…

  19. Oxidative Coupling of Enolates, Enol Silanes and Enamines: Methods and Natural Product Synthesis

    PubMed Central

    Guo, Fenghai; Clift, Michael D.

    2013-01-01

    The oxidative coupling of enolates, enol silanes, and enamines provides a direct method for the construction of useful 1,4-dicarbonyl synthons. Despite being first reported in 1935, with subsequent important advances beginning in the 1970’s, the development of this powerful reaction into a reliable methodology was somewhat limited. In recent years, there have been a number of reports from several research groups demonstrating advances in several neglected areas of oxidative coupling. This microreview summarizes these new advances in methodology and provides an overview of recent natural product syntheses that showcase the power of these transformations. PMID:23471479

  20. Advanced electromagnetic methods for aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Balanis, Constantine A.; Sun, Weimin; El-Sharawy, El-Budawy; Aberle, James T.; Birtcher, Craig R.; Peng, Jian; Tirkas, Panayiotis A.

    1992-01-01

    The Advanced Helicopter Electromagnetics (AHE) Industrial Associates Program continues its research on variety of main topics identified and recommended by the Advisory Task Force of the program. The research activities center on issues that advance technology related to helicopter electromagnetics. While most of the topics are a continuation of previous works, special effort has been focused on some of the areas due to recommendations from the last annual conference. The main topics addressed in this report are: composite materials, and antenna technology. The area of composite materials continues getting special attention in this period. The research has focused on: (1) measurements of the electrical properties of low-conductivity materials; (2) modeling of material discontinuity and their effects on the scattering patterns; (3) preliminary analysis on interaction of electromagnetic fields with multi-layered graphite fiberglass plates; and (4) finite difference time domain (FDTD) modeling of fields penetration through composite panels of a helicopter.

  1. Method and apparatus for advancing tethers

    DOEpatents

    Zollinger, W.T.

    1998-06-02

    A tether puller for advancing a tether through a channel may include a bellows assembly having a leading end fixedly attached to the tether at a first position and a trailing end fixedly attached to the tether at a second position so that the leading and trailing ends of the bellows assembly are located a substantially fixed distance apart. The bellows assembly includes a plurality of independently inflatable elements each of which may be separately inflated to an extended position and deflated to a retracted position. Each of the independently inflatable elements expands radially and axially upon inflation. An inflation system connected to the independently inflatable elements inflates and deflates selected ones of the independently inflatable elements to cause the bellows assembly to apply a tractive force to the tether and advance it in the channel. 9 figs.

  2. Method and apparatus for advancing tethers

    DOEpatents

    Zollinger, W. Thor

    1998-01-01

    A tether puller for advancing a tether through a channel may include a bellows assembly having a leading end fixedly attached to the tether at a first position and a trailing end fixedly attached to the tether at a second position so that the leading and trailing ends of the bellows assembly are located a substantially fixed distance apart. The bellows assembly includes a plurality of independently inflatable elements each of which may be separately inflated to an extended position and deflated to a retracted position. Each of the independently inflatable elements expands radially and axially upon inflation. An inflation system connected to the independently inflatable elements inflates and deflates selected ones of the independently inflatable elements to cause the bellows assembly to apply a tractive force to the tether and advance it in the channel.

  3. Methods of producing adsorption media including a metal oxide

    DOEpatents

    Mann, Nicholas R; Tranter, Troy J

    2014-03-04

    Methods of producing a metal oxide are disclosed. The method comprises dissolving a metal salt in a reaction solvent to form a metal salt/reaction solvent solution. The metal salt is converted to a metal oxide and a caustic solution is added to the metal oxide/reaction solvent solution to adjust the pH of the metal oxide/reaction solvent solution to less than approximately 7.0. The metal oxide is precipitated and recovered. A method of producing adsorption media including the metal oxide is also disclosed, as is a precursor of an active component including particles of a metal oxide.

  4. Application of advanced oxidation processes for TNT removal: A review.

    PubMed

    Ayoub, Kaidar; van Hullebusch, Eric D; Cassir, Michel; Bermond, Alain

    2010-06-15

    Nowadays, there are increasingly stringent regulations requiring drastic treatment of 2,4,6-trinitrotoluene (TNT) contaminated waters to generate treated waters which could be easily reused or released into the environment without any harmful effects. TNT is among the most highly suspected explosive compounds that interfere with groundwater system due to its high toxicity and low biodegradability. The present work is an overview of the literature on TNT removal from polluted waters and soils and, more particularly, its treatability by advanced oxidation processes (AOPs). Among the remediation technologies, AOPs constitute a promising technology for the treatment of wastewaters containing non-easily biodegradable organic compounds. Data concerning the degradation of TNT reported during the period 1990-2009 are evaluated in this review. Among the AOPs, the following techniques are successively debated: processes based on hydrogen peroxide (H(2)O(2)+UV, Fenton, photo-Fenton and Fenton-like processes), photocatalysis, processes based on ozone (O(3), O(3)+UV) and electrochemical processes. Kinetic constants related to TNT degradation and the different mechanistic degradation pathways are discussed. Possible future treatment strategies, such as, coupling AOP with biological treatment is also considered as a mean to improve TNT remediation efficiency and kinetic.

  5. Method of removing oxidized contaminants from water

    DOEpatents

    Amonette, J.E.; Fruchter, J.S.; Gorby, Y.A.; Cole, C.R.; Cantrell, K.J.; Kaplan, D.I.

    1998-07-21

    The present invention is a method for removing oxidized contaminant(s) from water. More specifically, the invention has the steps of contacting water containing the oxidized contaminant(s) with a layered aluminosilicate having Fe(II). The aluminosilicate may contain naturally occurring Fe(II), or the Fe(II) may be produced by reducing Fe(III) that is initially present. Reduction may be either by exposure to a chemical or biological reductant. Contacting the water containing oxidized contaminant(s) may be by (1) injection of Fe(II)-containing layered aluminosilicate, via a well, into a saturated zone where it is likely to intercept the contaminated water; (2) injection of contaminated water into a vessel containing the Fe(II)-bearing layered aluminosilicate; and (3) first reducing Fe(III) in the layered aluminosilicate to Fe(II) by injection of a biological or chemical reductant, into an aquifer or vessel having sufficient Fe(III)-bearing aluminosilicate to produce the necessary Fe(II). 8 figs.

  6. Method of removing oxidized contaminants from water

    DOEpatents

    Amonette, James E.; Fruchter, Jonathan S.; Gorby, Yuri A.; Cole, Charles R.; Cantrell, Kirk J.; Kaplan, Daniel I.

    1998-01-01

    The present invention is a method for removing oxidized contaminant(s) from water. More specifically, the invention has the steps of contacting water containing the oxidized contaminant(s) with a layered aluminosilicate having Fe(II). The aluminosilicate may contain naturally occurring Fe(II), or the Fe(II) may be produced by reducing Fe(III) that is initially present. Reduction may be either by exposure to a chemical or biological reductant. Contacting the water containing oxidized contaminant(s) may be by (1) injection of Fe(II)-containing layered aluminosilicate, via a well, into a saturated zone where it is likely to intercept the contaminated water; (2) injection of contaminated water into a vessel containing the Fe(II)-bearing layered aluminosilicate; and (3) first reducing Fe(III) in the layered aluminosilicate to Fe(II) by injection of a biological or chemical reductant, into an aquifer or vessel having sufficient Fe(III)-bearing aluminosilicate to produce the necessary Fe(II).

  7. Method and apparatus for nitrogen oxide determination

    DOEpatents

    Hohorst, Frederick A.

    1990-01-01

    Method and apparatus for determining nitrogen oxide content in a high temperature process gas, which involves withdrawing a sample portion of a high temperature gas containing nitrogen oxide from a source to be analyzed. The sample portion is passed through a restrictive flow conduit, which may be a capillary or a restriction orifice. The restrictive flow conduit is heated to a temperature sufficient to maintain the flowing sample portion at an elevated temperature at least as great as the temperature of the high temperature gas source, to thereby provide that deposition of ammonium nitrate within the restrictive flow conduit cannot occur. The sample portion is then drawn into an aspirator device. A heated motive gas is passed to the aspirator device at a temperature at least as great as the temperature of the high temperature gas source. The motive gas is passed through the nozzle of the aspirator device under conditions sufficient to aspirate the heated sample portion through the restrictive flow conduit and produce a mixture of the sample portion in the motive gas at a dilution of the sample portion sufficient to provide that deposition of ammonium nitrate from the mixture cannot occur at reduced temperature. A portion of the cooled dilute mixture is then passed to analytical means capable of detecting nitric oxide.

  8. Advanced methods of structural and trajectory analysis for transport aircraft

    NASA Technical Reports Server (NTRS)

    Ardema, Mark D.

    1995-01-01

    This report summarizes the efforts in two areas: (1) development of advanced methods of structural weight estimation, and (2) development of advanced methods of trajectory optimization. The majority of the effort was spent in the structural weight area. A draft of 'Analytical Fuselage and Wing Weight Estimation of Transport Aircraft', resulting from this research, is included as an appendix.

  9. Sono-bromination of aromatic compounds based on the ultrasonic advanced oxidation processes.

    PubMed

    Fujita, Mitsue; Lévêque, Jean-Marc; Komatsu, Naoki; Kimura, Takahide

    2015-11-01

    A novel, mild "sono-halogenation" of various aromatic compounds with potassium halide was investigated under ultrasound in a biphasic carbon tetrachloride/water medium. The feasibility study was first undertaken with the potassium bromide and then extended to chloride and iodide analogues. This methodology could be considered as a new expansion of the ultrasonic advanced oxidation processes (UAOPs) into a synthetic aspect as the developed methodology is linked to the sonolytic disappearance of carbon tetrachloride. Advantages of the present method are not only that the manipulation of the bromination is simple and green, but also that the halogenating agents used are readily available, inexpensive, and easy-handling.

  10. Advanced electromagnetic methods for aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Balanis, Constantine A.; El-Sharawy, El-Budawy; Hashemi-Yeganeh, Shahrokh; Aberle, James T.; Birtcher, Craig R.

    1991-01-01

    The Advanced Helicopter Electromagnetics is centered on issues that advance technology related to helicopter electromagnetics. Progress was made on three major topics: composite materials; precipitation static corona discharge; and antenna technology. In composite materials, the research has focused on the measurements of their electrical properties, and the modeling of material discontinuities and their effect on the radiation pattern of antennas mounted on or near material surfaces. The electrical properties were used to model antenna performance when mounted on composite materials. Since helicopter platforms include several antenna systems at VHF and UHF bands, measuring techniques are being explored that can be used to measure the properties at these bands. The effort on corona discharge and precipitation static was directed toward the development of a new two dimensional Voltage Finite Difference Time Domain computer program. Results indicate the feasibility of using potentials for simulating electromagnetic problems in the cases where potentials become primary sources. In antenna technology the focus was on Polarization Diverse Conformal Microstrip Antennas, Cavity Backed Slot Antennas, and Varactor Tuned Circular Patch Antennas. Numerical codes were developed for the analysis of two probe fed rectangular and circular microstrip patch antennas fed by resistive and reactive power divider networks.

  11. Advanced glycosylation products quench nitric oxide and mediate defective endothelium-dependent vasodilatation in experimental diabetes.

    PubMed Central

    Bucala, R; Tracey, K J; Cerami, A

    1991-01-01

    Nitric oxide (an endothelium-derived relaxing factor) induces smooth muscle relaxation and is an important mediator in the regulation of vascular tone. Advanced glycosylation end products, the glucose-derived moieties that form nonenzymatically and accumulate on long-lived tissue proteins, have been implicated in many of the complications of diabetes and normal aging. We demonstrate that advanced glycosylation products quench nitric oxide activity in vitro and in vivo. Acceleration of the advanced glycosylation process in vivo results in a time-dependent impairment in endothelium-dependent relaxation. Inhibition of advanced glycosylation with aminoguanidine prevents nitric oxide quenching, and ameliorates the vasodilatory impairment. These results implicate advanced glycosylation products as important modulators of nitric oxide activity and endothelium-dependent relaxation. PMID:1991829

  12. Method for producing metal oxide aerogels

    DOEpatents

    Tillotson, T.M.; Poco, J.F.; Hrubesh, L.W.; Thomas, I.M.

    1995-04-25

    A two-step hydrolysis-condensation method was developed to form metal oxide aerogels of any density, including densities of less than 0.003g/cm{sup 3} and greater than 0.27g/cm{sup 3}. High purity metal alkoxide is reacted with water, alcohol solvent, and an additive to form a partially condensed metal intermediate. All solvent and reaction-generated alcohol is removed, and the intermediate is diluted with a nonalcoholic solvent. The intermediate can be stored for future use to make aerogels of any density. The aerogels are formed by reacting the intermediate with water, nonalcoholic solvent, and a catalyst, and extracting the nonalcoholic solvent directly. The resulting monolithic aerogels are hydrophobic and stable under atmospheric conditions, and exhibit good optical transparency, high clarity, and homogeneity. The aerogels have high thermal insulation capacity, high porosity, mechanical strength and stability, and require shorter gelation times than aerogels formed by conventional methods. 8 figs.

  13. Method for producing metal oxide aerogels

    DOEpatents

    Tillotson, Thomas M.; Poco, John F.; Hrubesh, Lawrence W.; Thomas, Ian M.

    1995-01-01

    A two-step hydrolysis-condensation method was developed to form metal oxide aerogels of any density, including densities of less than 0.003g/cm.sup.3 and greater than 0.27g/cm.sup.3. High purity metal alkoxide is reacted with water, alcohol solvent, and an additive to form a partially condensed metal intermediate. All solvent and reaction-generated alcohol is removed, and the intermediate is diluted with a nonalcoholic solvent. The intermediate can be stored for future use to make aerogels of any density. The aerogels are formed by reacting the intermediate with water, nonalcoholic solvent, and a catalyst, and extracting the nonalcoholic solvent directly. The resulting monolithic aerogels are hydrophobic and stable under atmospheric conditions, and exhibit good optical transparency, high clarity, and homogeneity. The aerogels have high thermal insulation capacity, high porosity, mechanical strength and stability, and require shorter gelation times than aerogels formed by conventional methods.

  14. Oxidative degradation of endotoxin by advanced oxidation process (O3/H2O2 & UV/H2O2).

    PubMed

    Oh, Byung-Taek; Seo, Young-Suk; Sudhakar, Dega; Choe, Ji-Hyun; Lee, Sang-Myeong; Park, Youn-Jong; Cho, Min

    2014-08-30

    The presence of endotoxin in water environments may pose a serious public health hazard. We investigated the effectiveness of advanced oxidative processes (AOP: O3/H2O2 and UV/H2O2) in the oxidative degradation of endotoxin. In addition, we measured the release of endotoxin from Escherichia coli following typical disinfection methods, such as chlorine, ozone alone and UV, and compared it with the use of AOPs. Finally, we tested the AOP-treated samples in their ability to induce tumor necrosis factor alpha (TNF-α) in mouse peritoneal macrophages. The production of hydroxyl radical in AOPs showed superior ability to degrade endotoxin in buffered solution, as well as water samples from Korean water treatment facilities, with the ozone/H2O2 being more efficient compared to UV/H2O2. In addition, the AOPs proved effective not only in eliminating E. coli in the samples, but also in endotoxin degradation, while the standard disinfection methods lead to the release of endotoxin following the bacteria destruction. Furthermore, in the experiments with macrophages, the AOPs-deactivated endotoxin lead to the smallest induction of TNF-α, which shows the loss of inflammation activity, compared to ozone treatment alone. In conclusion, these results suggest that AOPs offer an effective and mild method for endotoxin degradation in the water systems.

  15. The study of leachate treatment by using three advanced oxidation process based wet air oxidation

    PubMed Central

    2013-01-01

    Wet air oxidation is regarded as appropriate options for wastewater treatment with average organic compounds. The general purpose of this research is to determine the efficiency of three wet air oxidation methods, wet oxidation with hydrogen peroxide and absorption with activated carbon in removing organic matter and nitrogenous compounds from Isfahan's urban leachate. A leachate sample with the volume of 1.5 liters entered into a steel reactor with the volume of three liters and was put under a 10-bar pressure, at temperatures of 100, 200, and 300° as well as three retention times of 30, 60, and 90 minutes. The sample was placed at 18 stages of leachate storage ponds in Isfahan Compost Plant with the volume of 20 liters, using three WPO, WAO methods and a combination of WAO/GAC for leachate pre-treatment. Thirty percent of pure oxygen and hydrogen peroxide were applied as oxidation agents. The COD removal efficiency in WAO method is 7.8-33.3%, in BOD is 14.7-50.6%, the maximum removal percentage (efficiency) for NH4-N is 53.3% and for NO3-N is 56.4-73.9%. The removal efficiency of COD and BOD5 is 4.6%-34 and 24%-50 respectively in WPO method. Adding GAC to the reactor, the removal efficiency of all parameters was improved. The maximum removal efficiency was increased 48% for COD, 31%-43.6 for BOD5 by a combinational method, and the ratio of BOD5/COD was also increased to 90%. In this paper, WAO and WPO process was used for Leachate pre-treatment and WAO/GAC combinational process was applied for improving the organic matter removal and leachate treatment; it was also determined that the recent process is much more efficient in removing resistant organic matter. PMID:23369258

  16. Modular Advanced Oxidation Process Enabled by Cathodic Hydrogen Peroxide Production

    PubMed Central

    2015-01-01

    Hydrogen peroxide (H2O2) is frequently used in combination with ultraviolet (UV) light to treat trace organic contaminants in advanced oxidation processes (AOPs). In small-scale applications, such as wellhead and point-of-entry water treatment systems, the need to maintain a stock solution of concentrated H2O2 increases the operational cost and complicates the operation of AOPs. To avoid the need for replenishing a stock solution of H2O2, a gas diffusion electrode was used to generate low concentrations of H2O2 directly in the water prior to its exposure to UV light. Following the AOP, the solution was passed through an anodic chamber to lower the solution pH and remove the residual H2O2. The effectiveness of the technology was evaluated using a suite of trace contaminants that spanned a range of reactivity with UV light and hydroxyl radical (HO•) in three different types of source waters (i.e., simulated groundwater, simulated surface water, and municipal wastewater effluent) as well as a sodium chloride solution. Irrespective of the source water, the system produced enough H2O2 to treat up to 120 L water d–1. The extent of transformation of trace organic contaminants was affected by the current density and the concentrations of HO• scavengers in the source water. The electrical energy per order (EEO) ranged from 1 to 3 kWh m–3, with the UV lamp accounting for most of the energy consumption. The gas diffusion electrode exhibited high efficiency for H2O2 production over extended periods and did not show a diminution in performance in any of the matrices. PMID:26039560

  17. Modular advanced oxidation process enabled by cathodic hydrogen peroxide production.

    PubMed

    Barazesh, James M; Hennebel, Tom; Jasper, Justin T; Sedlak, David L

    2015-06-16

    Hydrogen peroxide (H2O2) is frequently used in combination with ultraviolet (UV) light to treat trace organic contaminants in advanced oxidation processes (AOPs). In small-scale applications, such as wellhead and point-of-entry water treatment systems, the need to maintain a stock solution of concentrated H2O2 increases the operational cost and complicates the operation of AOPs. To avoid the need for replenishing a stock solution of H2O2, a gas diffusion electrode was used to generate low concentrations of H2O2 directly in the water prior to its exposure to UV light. Following the AOP, the solution was passed through an anodic chamber to lower the solution pH and remove the residual H2O2. The effectiveness of the technology was evaluated using a suite of trace contaminants that spanned a range of reactivity with UV light and hydroxyl radical (HO(•)) in three different types of source waters (i.e., simulated groundwater, simulated surface water, and municipal wastewater effluent) as well as a sodium chloride solution. Irrespective of the source water, the system produced enough H2O2 to treat up to 120 L water d(-1). The extent of transformation of trace organic contaminants was affected by the current density and the concentrations of HO(•) scavengers in the source water. The electrical energy per order (EEO) ranged from 1 to 3 kWh m(-3), with the UV lamp accounting for most of the energy consumption. The gas diffusion electrode exhibited high efficiency for H2O2 production over extended periods and did not show a diminution in performance in any of the matrices.

  18. Modular advanced oxidation process enabled by cathodic hydrogen peroxide production.

    PubMed

    Barazesh, James M; Hennebel, Tom; Jasper, Justin T; Sedlak, David L

    2015-06-16

    Hydrogen peroxide (H2O2) is frequently used in combination with ultraviolet (UV) light to treat trace organic contaminants in advanced oxidation processes (AOPs). In small-scale applications, such as wellhead and point-of-entry water treatment systems, the need to maintain a stock solution of concentrated H2O2 increases the operational cost and complicates the operation of AOPs. To avoid the need for replenishing a stock solution of H2O2, a gas diffusion electrode was used to generate low concentrations of H2O2 directly in the water prior to its exposure to UV light. Following the AOP, the solution was passed through an anodic chamber to lower the solution pH and remove the residual H2O2. The effectiveness of the technology was evaluated using a suite of trace contaminants that spanned a range of reactivity with UV light and hydroxyl radical (HO(•)) in three different types of source waters (i.e., simulated groundwater, simulated surface water, and municipal wastewater effluent) as well as a sodium chloride solution. Irrespective of the source water, the system produced enough H2O2 to treat up to 120 L water d(-1). The extent of transformation of trace organic contaminants was affected by the current density and the concentrations of HO(•) scavengers in the source water. The electrical energy per order (EEO) ranged from 1 to 3 kWh m(-3), with the UV lamp accounting for most of the energy consumption. The gas diffusion electrode exhibited high efficiency for H2O2 production over extended periods and did not show a diminution in performance in any of the matrices. PMID:26039560

  19. Method for hot pressing beryllium oxide articles

    DOEpatents

    Ballard, Ambrose H.; Godfrey, Jr., Thomas G.; Mowery, Erb H.

    1988-01-01

    The hot pressing of beryllium oxide powder into high density compacts with little or no density gradients is achieved by employing a homogeneous blend of beryllium oxide powder with a lithium oxide sintering agent. The lithium oxide sintering agent is uniformly dispersed throughout the beryllium oxide powder by mixing lithium hydroxide in an aqueous solution with beryllium oxide powder. The lithium hydroxide is converted in situ to lithium carbonate by contacting or flooding the beryllium oxide-lithium hydroxide blend with a stream of carbon dioxide. The lithium carbonate is converted to lithium oxide while remaining fixed to the beryllium oxide particles during the hot pressing step to assure uniform density throughout the compact.

  20. Method for producing nanostructured metal-oxides

    SciTech Connect

    Tillotson, Thomas M.; Simpson, Randall L.; Hrubesh, Lawrence W.; Gash, Alexander

    2006-01-17

    A synthetic route for producing nanostructure metal-oxide-based materials using sol-gel processing. This procedure employs the use of stable and inexpensive hydrated-metal inorganic salts and environmentally friendly solvents such as water and ethanol. The synthesis involves the dissolution of the metal salt in a solvent followed by the addition of a proton scavenger, which induces gel formation in a timely manner. Both critical point (supercritical extraction) and atmospheric (low temperature evaporation) drying may be employed to produce monolithic aerogels and xerogels, respectively. Using this method synthesis of metal-oxide nanostructured materials have been carried out using inorganic salts, such as of Fe.sup.3+, Cr.sup.3+, Al.sup.3+, Ga.sup.3+, In.sup.3+, Hf.sup.4+, Sn.sup.4+, Zr.sup.4+, Nb.sup.5+, W.sup.6+, Pr.sup.3+, Er.sup.3+, Nd.sup.3+, Ce.sup.3+, U.sup.3+ and Y.sup.3+. The process is general and nanostructured metal-oxides from the following elements of the periodic table can be made: Groups 2 through 13, part of Group 14 (germanium, tin, lead), part of Group 15 (antimony, bismuth), part of Group 16 (polonium), and the lanthanides and actinides. The sol-gel processing allows for the addition of insoluble materials (e.g., metals or polymers) to the viscous sol, just before gelation, to produce a uniformly distributed nanocomposites upon gelation. As an example, energetic nanocomposites of Fe.sub.xO.sub.y gel with distributed Al metal are readily made. The compositions are stable, safe, and can be readily ignited to thermitic reaction.

  1. Advanced particulate matter control apparatus and methods

    DOEpatents

    Miller, Stanley J.; Zhuang, Ye; Almlie, Jay C.

    2012-01-10

    Apparatus and methods for collection and removal of particulate matter, including fine particulate matter, from a gas stream, comprising a unique combination of high collection efficiency and ultralow pressure drop across the filter. The apparatus and method utilize simultaneous electrostatic precipitation and membrane filtration of a particular pore size, wherein electrostatic collection and filtration occur on the same surface.

  2. Integration of advanced oxidation technologies and biological processes: recent developments, trends, and advances.

    PubMed

    Tabrizi, Gelareh Bankian; Mehrvar, Mehrab

    2004-01-01

    The greatest challenge of today's wastewater treatment technology is to optimize the use of biological and chemical wastewater treatment processes. The choice of the process and/or integration of the processes depend strongly on the wastewater characteristics, concentrations, and the desired efficiencies. It has been observed by many investigators that the coupling of a bioreactor and advanced oxidation processes (AOPs) could reduce the final concentrations of the effluent to the desired values. However, optimizing the total cost of the treatment is a challenge, as AOPs are much more expensive than biological processes alone. Therefore, an appropriate design should not only consider the ability of this coupling to reduce the concentration of organic pollutants, but also try to obtain the desired results in a cost effective process. To consider the total cost of the treatment, the residence time in biological and photochemical reactors, the kinetic rates, and the capital and operating costs of the reactors play significant roles. In this study, recent developments and trends (1996-2003) on the integration of photochemical and biological processes for the degradation of problematic pollutants in wastewater have been reviewed. The conditions to get the optimum results from this integration have also been considered. In most of the studies, it has been shown that the integrated processes were more efficient than individual processes. However, slight changes in the configuration of the reactors, temperature, pH, treatment time, concentration of the oxidants, and microorganism's colonies could lead to a great deviation in results. It has also been demonstrated that the treatment cost in both reactors is a function of time, which changes by the flow rate. The minimum cost in the coupling of the processes cannot be achieved unless considering the best treatment time in chemical and biological reactors individually.

  3. Simultaneous nitrate reduction and acetaminophen oxidation using the continuous-flow chemical-less VUV process as an integrated advanced oxidation and reduction process.

    PubMed

    Moussavi, Gholamreza; Shekoohiyan, Sakine

    2016-11-15

    This work was aimed at investigating the performance of the continuous-flow VUV photoreactor as a novel chemical-less advanced process for simultaneously oxidizing acetaminophen (ACT) as a model of pharmaceuticals and reducing nitrate in a single reactor. Solution pH was an important parameter affecting the performance of VUV; the highest ACT oxidation and nitrate reduction attained at solution pH between 6 and 8. The ACT was oxidized mainly by HO while the aqueous electrons were the main working agents in the reduction of nitrate. The performance of VUV photoreactor improved with the increase of hydraulic retention time (HRT); the complete degradation of ACT and ∼99% reduction of nitrate with 100% N2 selectivity achieved at HRT of 80min. The VUV effluent concentrations of nitrite and ammonium at HRT of 80min were below the drinking water standards. The real water sample contaminated with the ACT and nitrate was efficiently treated in the VUV photoreactor. Therefore, the VUV photoreactor is a chemical-less advanced process in which both advanced oxidation and advanced reduction reactions are accomplished. This unique feature possesses VUV photoreactor as a promising method of treating water contaminated with both pharmaceutical and nitrate. PMID:27434736

  4. Simultaneous nitrate reduction and acetaminophen oxidation using the continuous-flow chemical-less VUV process as an integrated advanced oxidation and reduction process.

    PubMed

    Moussavi, Gholamreza; Shekoohiyan, Sakine

    2016-11-15

    This work was aimed at investigating the performance of the continuous-flow VUV photoreactor as a novel chemical-less advanced process for simultaneously oxidizing acetaminophen (ACT) as a model of pharmaceuticals and reducing nitrate in a single reactor. Solution pH was an important parameter affecting the performance of VUV; the highest ACT oxidation and nitrate reduction attained at solution pH between 6 and 8. The ACT was oxidized mainly by HO while the aqueous electrons were the main working agents in the reduction of nitrate. The performance of VUV photoreactor improved with the increase of hydraulic retention time (HRT); the complete degradation of ACT and ∼99% reduction of nitrate with 100% N2 selectivity achieved at HRT of 80min. The VUV effluent concentrations of nitrite and ammonium at HRT of 80min were below the drinking water standards. The real water sample contaminated with the ACT and nitrate was efficiently treated in the VUV photoreactor. Therefore, the VUV photoreactor is a chemical-less advanced process in which both advanced oxidation and advanced reduction reactions are accomplished. This unique feature possesses VUV photoreactor as a promising method of treating water contaminated with both pharmaceutical and nitrate.

  5. Remediation of a winery wastewater combining aerobic biological oxidation and electrochemical advanced oxidation processes.

    PubMed

    Moreira, Francisca C; Boaventura, Rui A R; Brillas, Enric; Vilar, Vítor J P

    2015-05-15

    Apart from a high biodegradable fraction consisting of organic acids, sugars and alcohols, winery wastewaters exhibit a recalcitrant fraction containing high-molecular-weight compounds as polyphenols, tannins and lignins. In this context, a winery wastewater was firstly subjected to a biological oxidation to mineralize the biodegradable fraction and afterwards an electrochemical advanced oxidation process (EAOP) was applied in order to mineralize the refractory molecules or transform them into simpler ones that can be further biodegraded. The biological oxidation led to above 97% removals of dissolved organic carbon (DOC), chemical oxygen demand (COD) and 5-day biochemical oxygen demand (BOD5), but was inefficient on the degradation of a bioresistant fraction corresponding to 130 mg L(-1) of DOC, 380 mg O2 L(-1) of COD and 8.2 mg caffeic acid equivalent L(-1) of total dissolved polyphenols. Various EAOPs such as anodic oxidation with electrogenerated H2O2 (AO-H2O2), electro-Fenton (EF), UVA photoelectro-Fenton (PEF) and solar PEF (SPEF) were then applied to the recalcitrant effluent fraction using a 2.2 L lab-scale flow plant containing an electrochemical cell equipped with a boron-doped diamond (BDD) anode and a carbon-PTFE air-diffusion cathode and coupled to a photoreactor with compound parabolic collectors (CPCs). The influence of initial Fe(2+) concentration and current density on the PEF process was evaluated. The relative oxidative ability of EAOPs increased in the order AO-H2O2 < EF < PEF ≤ SPEF. The SPEF process using an initial Fe(2+) concentration of 35 mg L(-1), current density of 25 mA cm(-2), pH of 2.8 and 25 °C reached removals of 86% on DOC and 68% on COD after 240 min, regarding the biologically treated effluent, along with energy consumptions of 45 kWh (kg DOC)(-1) and 5.1 kWh m(-3). After this coupled treatment, color, odor, COD, BOD5, NH4(+), NO3(-) and SO4(2-) parameters complied with the legislation targets and, in addition, a total

  6. Remediation of a winery wastewater combining aerobic biological oxidation and electrochemical advanced oxidation processes.

    PubMed

    Moreira, Francisca C; Boaventura, Rui A R; Brillas, Enric; Vilar, Vítor J P

    2015-05-15

    Apart from a high biodegradable fraction consisting of organic acids, sugars and alcohols, winery wastewaters exhibit a recalcitrant fraction containing high-molecular-weight compounds as polyphenols, tannins and lignins. In this context, a winery wastewater was firstly subjected to a biological oxidation to mineralize the biodegradable fraction and afterwards an electrochemical advanced oxidation process (EAOP) was applied in order to mineralize the refractory molecules or transform them into simpler ones that can be further biodegraded. The biological oxidation led to above 97% removals of dissolved organic carbon (DOC), chemical oxygen demand (COD) and 5-day biochemical oxygen demand (BOD5), but was inefficient on the degradation of a bioresistant fraction corresponding to 130 mg L(-1) of DOC, 380 mg O2 L(-1) of COD and 8.2 mg caffeic acid equivalent L(-1) of total dissolved polyphenols. Various EAOPs such as anodic oxidation with electrogenerated H2O2 (AO-H2O2), electro-Fenton (EF), UVA photoelectro-Fenton (PEF) and solar PEF (SPEF) were then applied to the recalcitrant effluent fraction using a 2.2 L lab-scale flow plant containing an electrochemical cell equipped with a boron-doped diamond (BDD) anode and a carbon-PTFE air-diffusion cathode and coupled to a photoreactor with compound parabolic collectors (CPCs). The influence of initial Fe(2+) concentration and current density on the PEF process was evaluated. The relative oxidative ability of EAOPs increased in the order AO-H2O2 < EF < PEF ≤ SPEF. The SPEF process using an initial Fe(2+) concentration of 35 mg L(-1), current density of 25 mA cm(-2), pH of 2.8 and 25 °C reached removals of 86% on DOC and 68% on COD after 240 min, regarding the biologically treated effluent, along with energy consumptions of 45 kWh (kg DOC)(-1) and 5.1 kWh m(-3). After this coupled treatment, color, odor, COD, BOD5, NH4(+), NO3(-) and SO4(2-) parameters complied with the legislation targets and, in addition, a total

  7. Indentation Methods in Advanced Materials Research Introduction

    SciTech Connect

    Pharr, George Mathews; Cheng, Yang-Tse; Hutchings, Ian; Sakai, Mototsugu; Moody, Neville; Sundararajan, G.; Swain, Michael V.

    2009-01-01

    Since its commercialization early in the 20th century, indentation testing has played a key role in the development of new materials and understanding their mechanical behavior. Progr3ess in the field has relied on a close marriage between research in the mechanical behavior of materials and contact mechanics. The seminal work of Hertz laid the foundations for bringing these two together, with his contributions still widely utilized today in examining elastic behavior and the physics of fracture. Later, the pioneering work of Tabor, as published in his classic text 'The Hardness of Metals', exapdned this understanding to address the complexities of plasticity. Enormous progress in the field has been achieved in the last decade, made possible both by advances in instrumentation, for example, load and depth-sensing indentation and scanning electron microscopy (SEM) and transmission electron microscopy (TEM) based in situ testing, as well as improved modeling capabilities that use computationally intensive techniques such as finite element analysis and molecular dynamics simulation. The purpose of this special focus issue is to present recent state of the art developments in the field.

  8. Advanced spectral methods for climatic time series

    USGS Publications Warehouse

    Ghil, M.; Allen, M.R.; Dettinger, M.D.; Ide, K.; Kondrashov, D.; Mann, M.E.; Robertson, A.W.; Saunders, A.; Tian, Y.; Varadi, F.; Yiou, P.

    2002-01-01

    The analysis of univariate or multivariate time series provides crucial information to describe, understand, and predict climatic variability. The discovery and implementation of a number of novel methods for extracting useful information from time series has recently revitalized this classical field of study. Considerable progress has also been made in interpreting the information so obtained in terms of dynamical systems theory. In this review we describe the connections between time series analysis and nonlinear dynamics, discuss signal- to-noise enhancement, and present some of the novel methods for spectral analysis. The various steps, as well as the advantages and disadvantages of these methods, are illustrated by their application to an important climatic time series, the Southern Oscillation Index. This index captures major features of interannual climate variability and is used extensively in its prediction. Regional and global sea surface temperature data sets are used to illustrate multivariate spectral methods. Open questions and further prospects conclude the review.

  9. Advances in methods for deepwater TLP installations

    SciTech Connect

    Wybro, P.G.

    1995-10-01

    This paper describes a method suitable for installing deepwater TLP structures in water depths beyond 3,000 ft. An overview is presented of previous TLP installation, wherein an evaluation is made of the various methods and their suitability to deepwater applications. A novel method for installation of deepwater TLP`s is described. This method of installation is most suitable for deepwater and/or large TLP structures, but can also be used in moderate water depth as well. The tendon installation method utilizes the so-called Platform Arrestor Concept (PAC), wherein tendon sections are transported by barges to site, and assembled vertically using a dynamically position crane vessel. The tendons are transferred to the platform where they are hung off until there are a full complement of tendons. The hull lock off operation is performed on all tendons simultaneously, avoiding dangerous platform resonant behavior. The installation calls for relatively simple installation equipment, and also enables the use of simple tendon tie-off equipment, such as a single piece nut.

  10. Method for preparing hollow metal oxide microsphere

    DOEpatents

    Schmitt, C.R.

    1974-02-12

    Hollow refractory metal oxide microspheres are prepared by impregnating resinous microspheres with a metallic compound, drying the impregnated microspheres, heating the microspheres slowly to carbonize the resin, and igniting the microspheres to remove the carbon and to produce the metal oxide. Zirconium oxide is given as an example. (Official Gazette)

  11. Reduction of antibiotic resistance genes in municipal wastewater effluent by advanced oxidation processes.

    PubMed

    Zhang, Yingying; Zhuang, Yao; Geng, Jinju; Ren, Hongqiang; Xu, Ke; Ding, Lili

    2016-04-15

    This study investigated the reduction of antibiotic resistance genes (ARGs), intI1 and 16S rRNA genes, by advanced oxidation processes (AOPs), namely Fenton oxidation (Fe(2+)/H2O2) and UV/H2O2 process. The ARGs include sul1, tetX, and tetG from municipal wastewater effluent. The results indicated that the Fenton oxidation and UV/H2O2 process could reduce selected ARGs effectively. Oxidation by the Fenton process was slightly better than that of the UV/H2O2 method. Particularly, for the Fenton oxidation, under the optimal condition wherein Fe(2+)/H2O2 had a molar ratio of 0.1 and a H2O2 concentration of 0.01molL(-1) with a pH of 3.0 and reaction time of 2h, 2.58-3.79 logs of target genes were removed. Under the initial effluent pH condition (pH=7.0), the removal was 2.26-3.35 logs. For the UV/H2O2 process, when the pH was 3.5 with a H2O2 concentration of 0.01molL(-1) accompanied by 30min of UV irradiation, all ARGs could achieve a reduction of 2.8-3.5 logs, and 1.55-2.32 logs at a pH of 7.0. The Fenton oxidation and UV/H2O2 process followed the first-order reaction kinetic model. The removal of target genes was affected by many parameters, including initial Fe(2+)/H2O2 molar ratios, H2O2 concentration, solution pH, and reaction time. Among these factors, reagent concentrations and pH values are the most important factors during AOPs.

  12. Advanced method for making vitreous waste forms

    SciTech Connect

    Pope, J.M.; Harrison, D.E.

    1980-01-01

    A process is described for making waste glass that circumvents the problems of dissolving nuclear waste in molten glass at high temperatures. Because the reactive mixing process is independent of the inherent viscosity of the melt, any glass composition can be prepared with equal facility. Separation of the mixing and melting operations permits novel glass fabrication methods to be employed.

  13. Analytical chemistry methods for mixed oxide fuel, March 1985

    SciTech Connect

    Not Available

    1985-03-01

    This standard provides analytical chemistry methods for the analysis of materials used to produce mixed oxide fuel. These materials are ceramic fuel and insulator pellets and the plutonium and uranium oxides and nitrates used to fabricate these pellets.

  14. Treatment of statin compounds by advanced oxidation processes: Kinetic considerations and destruction mechanisms

    NASA Astrophysics Data System (ADS)

    Razavi, Behnaz; Song, Weihua; Santoke, Hanoz; Cooper, William J.

    2011-03-01

    This study examined the use of advanced oxidation/reduction processes (AO/RPs) for the destruction of cholesterol lowering statin pharmaceuticals. AO/RPs which utilize the oxidizing hydroxyl radical ( rad OH) and reducing aqueous electron (e -aq), to degrade chemical contaminants are alternatives to traditional water treatment methods, and are alternatives as water reuse becomes more generally implemented. Four major statin pharmaceuticals, fluvastatin, lovastatin, pravastatin and simvastatin, were studied, and the absolute bimolecular reaction rate constants with rad OH determined, (6.96±0.16)×10 9, (2.92±0.06)×10 9, (4.16±0.13)×10 9, and (3.13±0.15)×10 9 M -1 s -1, and for e -aq (2.31±0.06)×10 9, (0.45±0.01)×10 9, (1.26±0.01)×10 9, and (0.69±0.02)×10 9 M -1 s -1, respectively. To provide additional information on the radicals formed upon oxidation, transient spectra were measured and the overall reaction efficiency determined. Radical-based destruction mechanisms for destruction of the statins are proposed based on the LC-MS determination of the stable reaction by-products formed using 137Cs γ-irradiation of statin solutions. Knowing the reaction rates, reaction efficiencies and destruction mechanisms of these compounds is essential for the consideration of the use of advanced oxidation/reduction processes for the destruction of statins in aqueous systems.

  15. Demonstrating Advanced Oxidation Coupled with Biodegradation for Removal of Carbamazepine (WERF Report INFR6SG09)

    EPA Science Inventory

    Carbamazepine is an anthropogenic pharmaceutical found in wastewater effluents that is quite resistant to removal by conventional wastewater treatment processes. Hydroxyl radical-based advanced oxidation processes can transform carbamazepine into degradation products but cannot m...

  16. Advanced oxidation processes coupled with electrocoagulation for the exhaustive abatement of Cr-EDTA.

    PubMed

    Durante, Christian; Cuscov, Marco; Isse, Abdirisak Ahmed; Sandonà, Giancarlo; Gennaro, Armando

    2011-02-01

    Using Cr-EDTA as a model system, a two-step method has been investigated for the abatement of persistent chromium complexes in water. The treatment consists of an oxidative decomposition of the organic ligands by means of ozonization or electrochemical oxidation at a boron doped diamond (BDD) electrode, followed by removal of the metal via electrochemical coagulation. In the designed synthetic waste, EDTA has been used both as a chelating agent and as a mimic of the organic content of a typical wastewater provided by a purification leather plant. A crucial point evaluated is the influence of the oxidative pretreatment on the chemical modification of the synthetic waste and hence on the electrocoagulation efficacy. Because of the great stability of Cr complexes, such as Cr-EDTA, the classical coagulation methods, based on ligand exchange between Cr(III) and Fe(II) or Fe(III), are ineffective toward Cr abatement in the presence of organic substances. On the contrary, when advanced oxidation processes (AOPs), such as ozonization or electrooxidation at a BDD anode are applied in series with electrocoagulation (EC), complete abatement of the recalcitrant Cr fraction can be achieved. ECs have been carried out by using Fe sacrificial anodes, with alternating polarization and complete Cr abatement (over 99%) has been obtained with modest charge consumption. It has been found that Cr(III) is first oxidized to Cr(VI) in the AOP preceding EC. Then, during EC, Cr(VI) is mainly reduced back to Cr(III) by electrogenerated Fe(II). Thus, Cr is mainly eliminated as Cr(III). However, a small fraction of Cr(VI) goes with the precipitate as confirmed by XPS analysis of the sludge. PMID:21255817

  17. Oxide semiconductor thin-film transistors: a review of recent advances.

    PubMed

    Fortunato, E; Barquinha, P; Martins, R

    2012-06-12

    Transparent electronics is today one of the most advanced topics for a wide range of device applications. The key components are wide bandgap semiconductors, where oxides of different origins play an important role, not only as passive component but also as active component, similar to what is observed in conventional semiconductors like silicon. Transparent electronics has gained special attention during the last few years and is today established as one of the most promising technologies for leading the next generation of flat panel display due to its excellent electronic performance. In this paper the recent progress in n- and p-type oxide based thin-film transistors (TFT) is reviewed, with special emphasis on solution-processed and p-type, and the major milestones already achieved with this emerging and very promising technology are summarizeed. After a short introduction where the main advantages of these semiconductors are presented, as well as the industry expectations, the beautiful history of TFTs is revisited, including the main landmarks in the last 80 years, finishing by referring to some papers that have played an important role in shaping transparent electronics. Then, an overview is presented of state of the art n-type TFTs processed by physical vapour deposition methods, and finally one of the most exciting, promising, and low cost but powerful technologies is discussed: solution-processed oxide TFTs. Moreover, a more detailed focus analysis will be given concerning p-type oxide TFTs, mainly centred on two of the most promising semiconductor candidates: copper oxide and tin oxide. The most recent data related to the production of complementary metal oxide semiconductor (CMOS) devices based on n- and p-type oxide TFT is also be presented. The last topic of this review is devoted to some emerging applications, finalizing with the main conclusions. Related work that originated at CENIMAT|I3N during the last six years is included in more detail, which

  18. Advanced Electromagnetic Methods for Aerospace Vehicles

    NASA Technical Reports Server (NTRS)

    Balanis, Constantine A.; Polycarpou, Anastasis; Birtcher, Craig R.; Georgakopoulos, Stavros; Han, Dong-Ho; Ballas, Gerasimos

    1999-01-01

    The imminent destructive threats of Lightning on helicopters and other airborne systems has always been a topic of great interest to this research grant. Previously, the lightning induced currents on the surface of the fuselage and its interior were predicted using the finite-difference time-domain (FDTD) method as well as the NEC code. The limitations of both methods, as applied to lightning, were identified and extensively discussed in the last meeting. After a thorough investigation of the capabilities of the FDTD, it was decided to incorporate into the numerical method a subcell model to accurately represent current diffusion through conducting materials of high conductivity and finite thickness. Because of the complexity of the model, its validity will be first tested for a one-dimensional FDTD problem. Although results are not available yet, the theory and formulation of the subcell model are presented and discussed here to a certain degree. Besides lightning induced currents in the interior of an aircraft, penetration of electromagnetic fields through apertures (e.g., windows and cracks) could also be devastating for the navigation equipment, electronics, and communications systems in general. The main focus of this study is understanding and quantifying field penetration through apertures. The simulation is done using the FDTD method and the predictions are compared with measurements and moment method solutions obtained from the NASA Langley Research Center. Cavity-backed slot (CBS) antennas or slot antennas in general have many applications in aircraft-satellite type of communications. These can be flushmounted on the surface of the fuselage and, therefore, they retain the aerodynamic shape of the aircraft. In the past, input impedance and radiation patterns of CBS antennas were computed using a hybrid FEM/MoM code. The analysis is now extended to coupling between two identical slot antennas mounted on the same structure. The predictions are performed

  19. Inactivation of Pseudomonas aeruginosa in electrochemical advanced oxidation process with diamond electrodes.

    PubMed

    Griessler, M; Knetsch, S; Schimpf, E; Schmidhuber, A; Schrammel, B; Wesner, W; Sommer, R; Kirschner, A K T

    2011-01-01

    The electrochemical advanced oxidation process (EAOP) with diamond electrodes may serve as an additional technology to the currently approved methods for water disinfection. Only few data exist on the microbicidal effect of the EAOP. The aim of our study was to investigate the microbicidal effect of a flow-through oxidation cell with diamond electrodes, using Pseudomonas aeruginosa as the test organism. Without electrical current the EAOP had no measurable effect on investigated microbiological and chemical parameters. For direct electrical current a stronger impact was observed at low flow rate than at higher flow rate. Depending on the contact time of the oxidants and the type of quenching reagent added, inactivation of P. aeruginosa was in the range log 1.6-3.6 at the higher flow rate and log 2.4-4.4 at the lower rate. Direct electrical current showed a stronger microbicidal effect than alternating current (maximum reduction log 4.0 and log 2.9, respectively). The microbiological results of experiments with this EAOP prototype revealed higher standard deviations than expected, based on our experience with standard water disinfection methods. Safe use of an EAOP system requires operating parameters to be defined and used accurately, and thus specific monitoring tests must be developed. PMID:21902043

  20. Inactivation of Pseudomonas aeruginosa in electrochemical advanced oxidation process with diamond electrodes.

    PubMed

    Griessler, M; Knetsch, S; Schimpf, E; Schmidhuber, A; Schrammel, B; Wesner, W; Sommer, R; Kirschner, A K T

    2011-01-01

    The electrochemical advanced oxidation process (EAOP) with diamond electrodes may serve as an additional technology to the currently approved methods for water disinfection. Only few data exist on the microbicidal effect of the EAOP. The aim of our study was to investigate the microbicidal effect of a flow-through oxidation cell with diamond electrodes, using Pseudomonas aeruginosa as the test organism. Without electrical current the EAOP had no measurable effect on investigated microbiological and chemical parameters. For direct electrical current a stronger impact was observed at low flow rate than at higher flow rate. Depending on the contact time of the oxidants and the type of quenching reagent added, inactivation of P. aeruginosa was in the range log 1.6-3.6 at the higher flow rate and log 2.4-4.4 at the lower rate. Direct electrical current showed a stronger microbicidal effect than alternating current (maximum reduction log 4.0 and log 2.9, respectively). The microbiological results of experiments with this EAOP prototype revealed higher standard deviations than expected, based on our experience with standard water disinfection methods. Safe use of an EAOP system requires operating parameters to be defined and used accurately, and thus specific monitoring tests must be developed.

  1. Cost estimating methods for advanced space systems

    NASA Technical Reports Server (NTRS)

    Cyr, Kelley

    1988-01-01

    Parametric cost estimating methods for space systems in the conceptual design phase are developed. The approach is to identify variables that drive cost such as weight, quantity, development culture, design inheritance, and time. The relationship between weight and cost is examined in detail. A theoretical model of cost is developed and tested statistically against a historical data base of major research and development programs. It is concluded that the technique presented is sound, but that it must be refined in order to produce acceptable cost estimates.

  2. Analytical and numerical methods; advanced computer concepts

    SciTech Connect

    Lax, P D

    1991-03-01

    This past year, two projects have been completed and a new is under way. First, in joint work with R. Kohn, we developed a numerical algorithm to study the blowup of solutions to equations with certain similarity transformations. In the second project, the adaptive mesh refinement code of Berger and Colella for shock hydrodynamic calculations has been parallelized and numerical studies using two different shared memory machines have been done. My current effort is towards the development of Cartesian mesh methods to solve pdes with complicated geometries. Most of the coming year will be spent on this project, which is joint work with Prof. Randy Leveque at the University of Washington in Seattle.

  3. Advances in organometallic synthesis with mechanochemical methods.

    PubMed

    Rightmire, Nicholas R; Hanusa, Timothy P

    2016-02-14

    Solvent-based syntheses have long been normative in all areas of chemistry, although mechanochemical methods (specifically grinding and milling) have been used to good effect for decades in organic, and to a lesser but growing extent, inorganic coordination chemistry. Organometallic synthesis, in contrast, represents a relatively underdeveloped area for mechanochemical research, and the potential benefits are considerable. From access to new classes of unsolvated complexes, to control over stoichiometries that have not been observed in solution routes, mechanochemical (or 'M-chem') approaches have much to offer the synthetic chemist. It has already become clear that removing the solvent from an organometallic reaction can change reaction pathways considerably, so that prediction of the outcome is not always straightforward. This Perspective reviews recent developments in the field, and describes equipment that can be used in organometallic synthesis. Synthetic chemists are encouraged to add mechanochemical methods to their repertoire in the search for new and highly reactive metal complexes and novel types of organometallic transformations.

  4. Advancements in Research Synthesis Methods: From a Methodologically Inclusive Perspective

    ERIC Educational Resources Information Center

    Suri, Harsh; Clarke, David

    2009-01-01

    The dominant literature on research synthesis methods has positivist and neo-positivist origins. In recent years, the landscape of research synthesis methods has changed rapidly to become inclusive. This article highlights methodologically inclusive advancements in research synthesis methods. Attention is drawn to insights from interpretive,…

  5. Current methods and advances in bone densitometry

    NASA Technical Reports Server (NTRS)

    Guglielmi, G.; Gluer, C. C.; Majumdar, S.; Blunt, B. A.; Genant, H. K.

    1995-01-01

    Bone mass is the primary, although not the only, determinant of fracture. Over the past few years a number of noninvasive techniques have been developed to more sensitively quantitate bone mass. These include single and dual photon absorptiometry (SPA and DPA), single and dual X-ray absorptiometry (SXA and DXA) and quantitative computed tomography (QCT). While differing in anatomic sites measured and in their estimates of precision, accuracy, and fracture discrimination, all of these methods provide clinically useful measurements of skeletal status. It is the intent of this review to discuss the pros and cons of these techniques and to present the new applications of ultrasound (US) and magnetic resonance (MRI) in the detection and management of osteoporosis.

  6. Advanced oxidation treatment of physico-chemically pre-treated olive mill industry effluent.

    PubMed

    Gomec, Cigdem Y; Erdim, Esra; Turan, Ilknur; Aydin, Ali F; Ozturk, Izzet

    2007-08-01

    In this study, the applicability of physico-chemical methods was investigated for the pre-treatment of the olive mill effluents prior to the discharge into the common sewerage ending with a municipal wastewater treatment plant. The samples were taken from an olive oil industry operated as three-phase process located in Turkey. Various pre-treatment methods including acid craking, polyelectrolyte and lime additions were applied. Advanced oxidation study using Fenton's process was also investigated following pre-treatment by acid cracking and cationic polyelectrolyte. Acid cracking alone gave satisfactory treatment efficiencies and polyelectrolite additions to the acid-cracked samples enhanced treatment efficiency. Since a complete treatment plant is available at the end of the sewer system, results indicated that the effluents of the investigated industry could be discharged into the municipal sewerage in the case of total chemical oxygen demand (COD(tot)), suspended solid (SS) and volatile suspended solid (VSS) concentrations according to the Turkish Water Pollution Control Regulation after pre-treatment with 5 ppm anionic polyelectrolyte following acid cracking. The minimum COD(tot), SS and VSS removals were observed when raw wastewater was pre-treated with lime and the discharge standards to the municipal sewer system could not be met. Advanced oxidation with Fenton's process was applied after acid cracking and cationic polyelectrolyte treatment in order to investigate further reduction in chemical oxygen demand (COD) concentration for minimizing the influence of this industrial discharge on the existing municipal wastewater treatment plant. Results indicated that COD(tot) removal increased up to 89% from 74% after Fenton's oxidation for the acid cracked samples in which cationic polyelectrolite (10 ppm) was added.

  7. Method for depositing an oxide coating

    NASA Technical Reports Server (NTRS)

    Mcdonald, G. E. (Inventor)

    1982-01-01

    A metal oxide coating is plated onto a metal substrate at the cathode from an acid solution which contains an oxidizing agent. The process is particularly useful for producing solar panels. Conventional plating at the cathode avoids the presence of oxidizing agents. Coatings made in accordance with the invention are stable both at high temperatures and while under the influence of high photon flux in the visible range.

  8. IMPROVED MAGNESIUM OXIDE SLIP CASTING METHOD

    DOEpatents

    Stoddard, S.D.; Nuckolls, D.E.

    1963-12-31

    A process for making an aqueous magnesium oxide slip casting slurry comprising the steps of mixing finely ground fused magnesium oxide with water, milling the slurry for at least 30 hours at a temperature of 2-10 deg C (the low temperature during milling inhibiting the formation of hydrated magnesium oxide), discharging the slurry from the mill, adding hydrochloric acid as a deflocculent, and adding a scum inhibitor is presented. (AEC)

  9. Treatment of coking wastewater by an advanced Fenton oxidation process using iron powder and hydrogen peroxide.

    PubMed

    Chu, Libing; Wang, Jianlong; Dong, Jing; Liu, Haiyang; Sun, Xulin

    2012-01-01

    In this study the treatment of coking wastewater was investigated by an advanced Fenton oxidation process using iron powder and hydrogen peroxide. Particular attention was paid to the effect of initial pH, dosage of H(2)O(2) and to improvement in biodegradation. The results showed that higher COD and total phenol removal rates were achieved with a decrease in initial pH and an increase in H(2)O(2) dosage. At an initial pH of less than 6.5 and H(2)O(2) concentration of 0.3 M, COD removal reached 44-50% and approximately 95% of total phenol removal was achieved at a reaction time of 1 h. The oxygen uptake rate of the effluent measured at a reaction time of 1h increased by approximately 65% compared to that of the raw coking wastewater. This indicated that biodegradation of the coking wastewater was significantly improved. Several organic compounds, including bifuran, quinoline, resorcinol and benzofuranol were removed completely as determined by GC-MS analysis. The advanced Fenton oxidation process is an effective pretreatment method for the removal of organic pollutants from coking wastewater. This process increases biodegradation, and may be combined with a classical biological process to achieve effluent of high quality. PMID:22014660

  10. Electrochemical advanced oxidation and biological processes for wastewater treatment: a review of the combined approaches.

    PubMed

    Ganzenko, Oleksandra; Huguenot, David; van Hullebusch, Eric D; Esposito, Giovanni; Oturan, Mehmet A

    2014-01-01

    As pollution becomes one of the biggest environmental challenges of the twenty-first century, pollution of water threatens the very existence of humanity, making immediate action a priority. The most persistent and hazardous pollutants come from industrial and agricultural activities; therefore, effective treatment of this wastewater prior to discharge into the natural environment is the solution. Advanced oxidation processes (AOPs) have caused increased interest due to their ability to degrade hazardous substances in contrast to other methods, which mainly only transfer pollution from wastewater to sludge, a membrane filter, or an adsorbent. Among a great variety of different AOPs, a group of electrochemical advanced oxidation processes (EAOPs), including electro-Fenton, is emerging as an environmental-friendly and effective treatment process for the destruction of persistent hazardous contaminants. The only concern that slows down a large-scale implementation is energy consumption and related investment and operational costs. A combination of EAOPs with biological treatment is an interesting solution. In such a synergetic way, removal efficiency is maximized, while minimizing operational costs. The goal of this review is to present cutting-edge research for treatment of three common and problematic pollutants and effluents: dyes and textile wastewater, olive processing wastewater, and pharmaceuticals and hospital wastewater. Each of these types is regarded in terms of recent scientific research on individual electrochemical, individual biological and a combined synergetic treatment.

  11. Method and ethics in advancing jury research.

    PubMed

    Robertshaw, P

    1998-10-01

    In this article the contemporary problems of the jury and jury research are considered. This is timely, in view of the current Home Office Consultation Paper on the future of, and alternatives to, the jury in serious fraud trials, to which the author has submitted representations on its jury aspects. The research position is dominated by the prohibitions in the Contempt of Court Act 1981. The types of indirect research on jury deliberation which have been achieved within this stricture are outlined. In the USA, direct research of the jury is possible but, for historical reasons, it has been in television documentaries that direct observation of the deliberation process has been achieved. The first issue is discussed and the problems of inauthenticity, 'the observer effect', and of existential invalidity in 'mock' or 'shadow' juries are noted. Finally, the kinds of issues that could be addressed if licensed jury deliberation research was legalized, are proposed. It is also suggested that there are methods available to transcend the problems associated with American direct research. PMID:9808945

  12. Cost estimating methods for advanced space systems

    NASA Technical Reports Server (NTRS)

    Cyr, Kelley

    1994-01-01

    NASA is responsible for developing much of the nation's future space technology. Cost estimates for new programs are required early in the planning process so that decisions can be made accurately. Because of the long lead times required to develop space hardware, the cost estimates are frequently required 10 to 15 years before the program delivers hardware. The system design in conceptual phases of a program is usually only vaguely defined and the technology used is so often state-of-the-art or beyond. These factors combine to make cost estimating for conceptual programs very challenging. This paper describes an effort to develop parametric cost estimating methods for space systems in the conceptual design phase. The approach is to identify variables that drive cost such as weight, quantity, development culture, design inheritance and time. The nature of the relationships between the driver variables and cost will be discussed. In particular, the relationship between weight and cost will be examined in detail. A theoretical model of cost will be developed and tested statistically against a historical database of major research and development projects.

  13. Advanced electromagnetic methods for aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Balanis, Constantine A.; Choi, Jachoon; El-Sharawy, El-Budawy; Hashemi-Yeganeh, Shahrokh; Birtcher, Craig R.

    1990-01-01

    High- and low-frequency methods to analyze various radiation elements located on aerospace vehicles with combinations of conducting, nonconducting, and energy absorbing surfaces and interfaces. The focus was on developing fundamental concepts, techniques, and algorithms which would remove some of the present limitations in predicting radiation characteristics of antennas on complex aerospace vehicles. In order to accomplish this, the following subjects were examined: (1) the development of techniques for rigorous analysis of surface discontinuities of metallic and nonmetallic surfaces using the equivalent surface impedance concept and Green's function; (2) the effects of anisotropic material on antenna radiation patterns through the use of an equivalent surface impedance concept which is incorporated into the existing numerical electromagnetics computer codes; and (3) the fundamental concepts of precipitation static (P-Static), such as formulations and analytical models. A computer code was used to model the P-Static process on a simple structure. Measurement techniques were also developed to characterized the electrical properties at microwave frequencies. Samples of typical materials used in airframes were tested and the results are included.

  14. Advanced Fuzzy Potential Field Method for Mobile Robot Obstacle Avoidance

    PubMed Central

    Park, Jong-Wook; Kwak, Hwan-Joo; Kang, Young-Chang; Kim, Dong W.

    2016-01-01

    An advanced fuzzy potential field method for mobile robot obstacle avoidance is proposed. The potential field method primarily deals with the repulsive forces surrounding obstacles, while fuzzy control logic focuses on fuzzy rules that handle linguistic variables and describe the knowledge of experts. The design of a fuzzy controller—advanced fuzzy potential field method (AFPFM)—that models and enhances the conventional potential field method is proposed and discussed. This study also examines the rule-explosion problem of conventional fuzzy logic and assesses the performance of our proposed AFPFM through simulations carried out using a mobile robot. PMID:27123001

  15. Advanced Fuzzy Potential Field Method for Mobile Robot Obstacle Avoidance.

    PubMed

    Park, Jong-Wook; Kwak, Hwan-Joo; Kang, Young-Chang; Kim, Dong W

    2016-01-01

    An advanced fuzzy potential field method for mobile robot obstacle avoidance is proposed. The potential field method primarily deals with the repulsive forces surrounding obstacles, while fuzzy control logic focuses on fuzzy rules that handle linguistic variables and describe the knowledge of experts. The design of a fuzzy controller--advanced fuzzy potential field method (AFPFM)--that models and enhances the conventional potential field method is proposed and discussed. This study also examines the rule-explosion problem of conventional fuzzy logic and assesses the performance of our proposed AFPFM through simulations carried out using a mobile robot. PMID:27123001

  16. Application of electrochemical advanced oxidation processes to the mineralization of the herbicide diuron.

    PubMed

    Pipi, Angelo R F; Sirés, Ignasi; De Andrade, Adalgisa R; Brillas, Enric

    2014-08-01

    Here, solutions with 0.185mM of the herbicide diuron of pH 3.0 have been treated by electrochemical advanced oxidation processes (EAOPs) like electrochemical oxidation with electrogenerated H2O2 (EO-H2O2), electro-Fenton (EF) and UVA photoelectro-Fenton (PEF) or solar PEF (SPEF). Trials were performed in stirred tank reactors of 100mL and in a recirculation flow plant of 2.5L using a filter-press reactor with a Pt or boron-doped diamond (BDD) anode and an air-diffusion cathode for H2O2 electrogeneration. Oxidant hydroxyl radicals were formed from water oxidation at the anode and/or in the bulk from Fenton's reaction between added Fe(2+) and generated H2O2. In both systems, the relative oxidation ability of the EAOPs increased in the sequence EO-H2O2method, yielding 93% mineralization after 360 min at 100 mA cm(-2). In the flow plant, the SPEF process attained a maximum mineralization of 70% at 100 mA cm(-2). Lower current densities slightly reduced the mineralization degree in SPEF, enhancing the current efficiency and dropping the energy consumption. The diuron decay always obeyed a pseudo-first-order kinetics, with a much greater apparent rate constant in EF and SPEF compared to EO-H2O2. Oxalic and oxamic acids were detected as final carboxylic acids. Ammonium and chloride ions were also released, the latter ion being partially converted into chlorate and perchlorate ions at the BDD surface.

  17. METHOD FOR PREPARATION OF SINTERABLE BERYLLIUM OXIDE

    DOEpatents

    Sturm, B.J.

    1963-08-13

    High-purity beryllium oxide for nuclear reactor applications can be prepared by precipitation of beryllium oxalate monohydrate from aqueous solution at a temperature above 50 deg C and subsequent calcination of the precipitate. Improved purification with respect to metallic impurities is obtained, and the product beryllium oxide sinters reproducibly to a high density. (AEC)

  18. Method for preparing hydrous zirconium oxide gels and spherules

    DOEpatents

    Collins, Jack L.

    2003-08-05

    Methods for preparing hydrous zirconium oxide spherules, hydrous zirconium oxide gels such as gel slabs, films, capillary and electrophoresis gels, zirconium monohydrogen phosphate spherules, hydrous zirconium oxide spherules having suspendable particles homogeneously embedded within to form a composite sorbent, zirconium monohydrogen phosphate spherules having suspendable particles of at least one different sorbent homogeneously embedded within to form a composite sorbent having a desired crystallinity, zirconium oxide spherules having suspendable particles homogeneously embedded within to form a composite, hydrous zirconium oxide fiber materials, zirconium oxide fiber materials, hydrous zirconium oxide fiber materials having suspendable particles homogeneously embedded within to form a composite, zirconium oxide fiber materials having suspendable particles homogeneously embedded within to form a composite and spherules of barium zirconate. The hydrous zirconium oxide spherules and gel forms prepared by the gel-sphere, internal gelation process are useful as inorganic ion exchangers, catalysts, getters and ceramics.

  19. Methods for making lithium vanadium oxide electrode materials

    DOEpatents

    Schutts, Scott M.; Kinney, Robert J.

    2000-01-01

    A method of making vanadium oxide formulations is presented. In one method of preparing lithium vanadium oxide for use as an electrode material, the method involves: admixing a particulate form of a lithium compound and a particulate form of a vanadium compound; jet milling the particulate admixture of the lithium and vanadium compounds; and heating the jet milled particulate admixture at a temperature below the melting temperature of the admixture to form lithium vanadium oxide.

  20. Method for producing high quality oxide films on substrates

    DOEpatents

    Ruckman, M.W.; Strongin, M.; Gao, Y.L.

    1993-11-23

    A method is described for providing an oxide film of a material on the surface of a substrate using a reactive deposition of the material onto the substrate surface in the presence of a solid or liquid layer of an oxidizing gas. The oxidizing gas is provided on the substrate surface in an amount sufficient to dissipate the latent heat of condensation occurring during deposition as well as creating a favorable oxidizing environment for the material. 4 figures.

  1. Method for producing high quality oxide films on substrates

    DOEpatents

    Ruckman, Mark W.; Strongin, Myron; Gao, Yong L.

    1993-01-01

    A method for providing an oxide film of a material on the surface of a substrate using a reactive deposition of the material onto the substrate surface in the presence of a solid or liquid layer of an oxidizing gas. The oxidizing gas is provided on the substrate surface in an amount sufficient to dissipate the latent heat of condensation occurring during deposition as well as creating a favorable oxidizing environment for the material.

  2. Advanced Ablative Insulators and Methods of Making Them

    NASA Technical Reports Server (NTRS)

    Congdon, William M.

    2005-01-01

    Advanced ablative (more specifically, charring) materials that provide temporary protection against high temperatures, and advanced methods of designing and manufacturing insulators based on these materials, are undergoing development. These materials and methods were conceived in an effort to replace the traditional thermal-protection systems (TPSs) of re-entry spacecraft with robust, lightweight, better-performing TPSs that can be designed and manufactured more rapidly and at lower cost. These materials and methods could also be used to make improved TPSs for general aerospace, military, and industrial applications.

  3. Strategy to Promote Active Learning of an Advanced Research Method

    ERIC Educational Resources Information Center

    McDermott, Hilary J.; Dovey, Terence M.

    2013-01-01

    Research methods courses aim to equip students with the knowledge and skills required for research yet seldom include practical aspects of assessment. This reflective practitioner report describes and evaluates an innovative approach to teaching and assessing advanced qualitative research methods to final-year psychology undergraduate students. An…

  4. Oxidized film structure and method of making epitaxial metal oxide structure

    DOEpatents

    Gan, Shupan [Richland, WA; Liang, Yong [Richland, WA

    2003-02-25

    A stable oxidized structure and an improved method of making such a structure, including an improved method of making an interfacial template for growing a crystalline metal oxide structure, are disclosed. The improved method comprises the steps of providing a substrate with a clean surface and depositing a metal on the surface at a high temperature under a vacuum to form a metal-substrate compound layer on the surface with a thickness of less than one monolayer. The compound layer is then oxidized by exposing the compound layer to essentially oxygen at a low partial pressure and low temperature. The method may further comprise the step of annealing the surface while under a vacuum to further stabilize the oxidized film structure. A crystalline metal oxide structure may be subsequently epitaxially grown by using the oxidized film structure as an interfacial template and depositing on the interfacial template at least one layer of a crystalline metal oxide.

  5. Advanced oxide dispersion strengthened sheet alloys for improved combustor durability

    NASA Technical Reports Server (NTRS)

    Henricks, R. J.

    1981-01-01

    Burner design modifications that will take advantage of the improved creep and cyclic oxidation resistance of oxide dispersion strengthened (ODS) alloys while accommodating the reduced fatigue properties of these materials were evaluated based on preliminary analysis and life predictions, on construction and repair feasibility, and on maintenance and direct operating costs. Two designs - the film cooled, segmented louver and the transpiration cooled, segmented twin Wall - were selected for low cycle fatigue (LCF) component testing. Detailed thermal and structural analysis of these designs established the strain range and temprature at critical locations resulting in predicted lives of 10,000 cycles for MA 956 alloy. The ODs alloys, MA 956 and HDA 8077, demonstrated a 167 C (300 F) temperature advantage over Hastelloy X alloy in creep strength and oxidation resistance. The MA 956 alloy was selected for mechanical property and component test evaluations. The MA 956 alloy was superior to Hastelloy X in LCF component testing of the film cooled, segmented louver design.

  6. A Primer In Advanced Fatigue Life Prediction Methods

    NASA Technical Reports Server (NTRS)

    Halford, Gary R.

    2000-01-01

    Metal fatigue has plagued structural components for centuries, and it remains a critical durability issue in today's aerospace hardware. This is true despite vastly improved and advanced materials, increased mechanistic understanding, and development of accurate structural analysis and advanced fatigue life prediction tools. Each advance is quickly taken advantage of to produce safer, more reliable more cost effective, and better performing products. In other words, as the envelop is expanded, components are then designed to operate just as close to the newly expanded envelop as they were to the initial one. The problem is perennial. The economic importance of addressing structural durability issues early in the design process is emphasized. Tradeoffs with performance, cost, and legislated restrictions are pointed out. Several aspects of structural durability of advanced systems, advanced materials and advanced fatigue life prediction methods are presented. Specific items include the basic elements of durability analysis, conventional designs, barriers to be overcome for advanced systems, high-temperature life prediction for both creep-fatigue and thermomechanical fatigue, mean stress effects, multiaxial stress-strain states, and cumulative fatigue damage accumulation assessment.

  7. Partial oxidation power plant with reheating and method thereof

    DOEpatents

    Newby, Richard A.; Yang, Wen-Ching; Bannister, Ronald L.

    1999-01-01

    A system and method for generating power having an air compression/partial oxidation system, a turbine, and a primary combustion system. The air compression/partial oxidation system receives a first air stream and a fuel stream and produces a first partially oxidized fuel stream and a first compressed air stream therefrom. The turbine expands the first partially oxidized fuel stream while being cooled by the first compressed air stream to produce a heated air stream. The heated air stream is injected into the expanding first partially oxidized fuel stream, thereby reheating it in the turbine. A second partially oxidized fuel stream is emitted from the turbine. The primary combustion system receives said second partially oxidized fuel stream and a second air stream, combusts said second partially oxidized fuel stream, and produces rotating shaft power and an emission stream therefrom.

  8. Partial oxidation power plant with reheating and method thereof

    DOEpatents

    Newby, R.A.; Yang, W.C.; Bannister, R.L.

    1999-08-10

    A system and method are disclosed for generating power having an air compression/partial oxidation system, a turbine, and a primary combustion system. The air compression/partial oxidation system receives a first air stream and a fuel stream and produces a first partially oxidized fuel stream and a first compressed air stream therefrom. The turbine expands the first partially oxidized fuel stream while being cooled by the first compressed air stream to produce a heated air stream. The heated air stream is injected into the expanding first partially oxidized fuel stream, thereby reheating it in the turbine. A second partially oxidized fuel stream is emitted from the turbine. The primary combustion system receives said second partially oxidized fuel stream and a second air stream, combusts said second partially oxidized fuel stream, and produces rotating shaft power and an emission stream therefrom. 2 figs.

  9. Thermochemical Compatibility and Oxidation Resistance of Advanced LWR Fuel Cladding

    DOE PAGES

    Besmann, T. M.; Yamamoto, Y.; Unocic, K. A.

    2016-06-21

    We assessed the thermochemical compatibility of potential replacement cladding materials for zirconium alloys in light water reactors. Considered were FeCrAl steel (similar to Kanthal APMT), Nb-1%Zr (similar to PWC-11), and a hybrid SiC-composite with a metallic barrier layer. The niobium alloy was also seen as requiring an oxidation protective layer, and a diffusion silicide was investigated. Metallic barrier layers for the SiC-composite reviewed included a FeCrAl alloy, Nb-1%Zr, and chromium. Thermochemical calculations were performed to determine oxidation behavior of the materials in steam, and for hybrid SiC-composites possible interactions between the metallic layer and SiC. Additionally, experimental exposures of SiC-alloymore » reaction couples at 673K, 1073K, and 1273K for 168 h in an inert atmosphere were made and microanalysis performed. Whereas all materials were determined to oxidize under higher oxygen partial pressures in the steam environment, these varied by material with expected protective oxides forming. Finally, the computed and experimental results indicate the formation of liquid phase eutectic in the FeCrAl-SiC system at the higher temperatures.« less

  10. Modified lithium vanadium oxide electrode materials products and methods

    DOEpatents

    Thackeray, Michael M.; Kahaian, Arthur J.; Visser, Donald R.; Dees, Dennis W.; Benedek, Roy

    1999-12-21

    A method of improving certain vanadium oxide formulations is presented. The method concerns fluorine doping formulations having a nominal formula of LiV.sub.3 O.sub.8. Preferred average formulations are provided wherein the average oxidation state of the vanadium is at least 4.6. Herein preferred fluorine doped vanadium oxide materials, electrodes using such materials, and batteries including at least one electrode therein comprising such materials are provided.

  11. Apparatus and method for constant flow oxidizing of organic materials

    DOEpatents

    Surma, Jeffrey E.; Nelson, Norvell; Steward, G. Anthony; Bryan, Garry H.

    1999-01-01

    The invention is a method and apparatus using high cerium concentration in the anolyte of an electrochemical cell to oxidize organic materials. The method and apparatus further use an ultrasonic mixer to enhance the oxidation rate of the organic material in the electrochemical cell. A reaction vessel provides an advantage of independent reaction temperature control and electrochemical cell temperature control. A separate or independent reaction vessel may be used without an ultrasonic mixer to oxidize gaseous phase organic materials.

  12. Advanced stress analysis methods applicable to turbine engine structures

    NASA Technical Reports Server (NTRS)

    Pian, T. H. H.

    1985-01-01

    Advanced stress analysis methods applicable to turbine engine structures are investigated. Constructions of special elements which containing traction-free circular boundaries are investigated. New versions of mixed variational principle and version of hybrid stress elements are formulated. A method is established for suppression of kinematic deformation modes. semiLoof plate and shell elements are constructed by assumed stress hybrid method. An elastic-plastic analysis is conducted by viscoplasticity theory using the mechanical subelement model.

  13. Advanced surface paneling method for subsonic and supersonic flow

    NASA Technical Reports Server (NTRS)

    Erickson, L. L.; Johnson, F. T.; Ehlers, F. E.

    1976-01-01

    Numerical results illustrating the capabilities of an advanced aerodynamic surface paneling method are presented. The method is applicable to both subsonic and supersonic flow, as represented by linearized potential flow theory. The method is based on linearly varying sources and quadratically varying doublets which are distributed over flat or curved panels. These panels are applied to the true surface geometry of arbitrarily shaped three dimensional aerodynamic configurations.

  14. Microchannel apparatus and methods of conducting catalyzed oxidative dehydrogenation

    DOEpatents

    Tonkovich, Anna Lee; Yang, Bin; Perry, Steven T.; Mazanec, Terry; Arora, Ravi; Daly, Francis P.; Long, Richard; Yuschak, Thomas D.; Neagle, Paul W.; Glass, Amanda

    2011-08-16

    Methods of oxidative dehydrogenation are described. Surprisingly, Pd and Au alloys of Pt have been discovered to be superior for oxidative dehydrogenation in microchannels. Methods of forming these catalysts via an electroless plating methodology are also described. An apparatus design that minimizes heat transfer to the apparatus' exterior is also described.

  15. Method for fluorination of uranium oxide

    DOEpatents

    Petit, George S.

    1987-01-01

    Highly pure uranium hexafluoride is made from uranium oxide and fluorine. The uranium oxide, which includes UO.sub.3, UO.sub.2, U.sub.3 O.sub.8 and mixtures thereof, is introduced together with a small amount of a fluorine-reactive substance, selected from alkali chlorides, silicon dioxide, silicic acid, ferric oxide, and bromine, into a constant volume reaction zone. Sufficient fluorine is charged into the zone at a temperature below approximately 0.degree. C. to provide an initial pressure of at least approximately 600 lbs/sq. in. at the ambient atmospheric temperature. The temperature is then allowed to rise in the reaction zone until reaction occurs.

  16. Advanced digital methods for solid propellant burning rate determination

    NASA Astrophysics Data System (ADS)

    Jones, Daniel A.

    The work presented here is a study of a digital method for determining the combustion bomb burning rate of a fuel-rich gas generator propellant sample using the ultrasonic pulse-echo technique. The advanced digital method, which places user defined limits on the search for the ultrasonic echo from the burning surface, is computationally faster than the previous cross correlation method, and is able to analyze data for this class of propellant that the previous cross correlation data reduction method could not. For the conditions investigated, the best fit burning rate law at 800 psi from the ultrasonic technique and advanced cross correlation method is within 3 percent of an independent analysis of the same data, and is within 5 percent of the best fit burning rate law found from parallel research of the same propellant in a motor configuration.

  17. METHOD FOR REMOVING SODIUM OXIDE FROM LIQUID SODIUM

    DOEpatents

    Bruggeman, W.H.; Voorhees, B.G.

    1957-12-01

    A method is described for removing sodium oxide from a fluent stream of liquid sodium by coldtrapping the sodium oxide. Apparatus utilizing this method is disclosed in United States Patent No. 2,745,552. Sodium will remain in a molten state at temperatures below that at which sodium oxide will crystallize out and form solid deposits, therefore, the contaminated stream of sodium is cooled to a temperature at which the solubility of sodium oxide in sodium is substantially decreased. Thereafter the stream of sodium is passed through a bed of stainless steel wool maintained at a temperature below that of the stream. The stream is kept in contact with the wool until the sodium oxide is removed by crystal growth on the wool, then the stream is reheated and returned to the system. This method is useful in purifying reactor coolants where the sodium oxide would otherwise deposit out on the walls and eventually plug the coolant tubes.

  18. Microbial-mediated method for metal oxide nanoparticle formation

    DOEpatents

    Rondinone, Adam J.; Moon, Ji Won; Love, Lonnie J.; Yeary, Lucas W.; Phelps, Tommy J.

    2015-09-08

    The invention is directed to a method for producing metal oxide nanoparticles, the method comprising: (i) subjecting a combination of reaction components to conditions conducive to microbial-mediated formation of metal oxide nanoparticles, wherein said combination of reaction components comprise: metal-reducing microbes, a culture medium suitable for sustaining said metal-reducing microbes, an effective concentration of one or more surfactants, a reducible metal oxide component containing one or more reducible metal species, and one or more electron donors that provide donatable electrons to said metal-reducing microbes during consumption of the electron donor by said metal-reducing microbes; and (ii) isolating said metal oxide nanoparticles, which contain a reduced form of said reducible metal oxide component. The invention is also directed to metal oxide nanoparticle compositions produced by the inventive method.

  19. Method For Selective Catalytic Reduction Of Nitrogen Oxides

    DOEpatents

    Mowery-Evans, Deborah L.; Gardner, Timothy J.; McLaughlin, Linda I.

    2005-02-15

    A method for catalytically reducing nitrogen oxide compounds (NO.sub.x, defined as nitric oxide, NO, +nitrogen dioxide, NO.sub.2) in a gas by a material comprising a base metal consisting essentially of CuO and Mn, and oxides of Mn, on an activated metal hydrous metal oxide support, such as HMO:Si. A promoter, such as tungsten oxide or molybdenum oxide, can be added and has been shown to increase conversion efficiency. This method provides good conversion of NO.sub.x to N.sub.2, good selectivity, good durability, resistance to SO.sub.2 aging and low toxicity compared with methods utilizing vanadia-based catalysts.

  20. Method for selective catalytic reduction of nitrogen oxides

    DOEpatents

    Mowery-Evans, Deborah L.; Gardner, Timothy J.; McLaughlin, Linda I.

    2005-02-15

    A method for catalytically reducing nitrogen oxide compounds (NO.sub.x, defined as nitric oxide, NO, +nitrogen dioxide, NO.sub.2) in a gas by a material comprising a base metal consisting essentially of CuO and Mn, and oxides of Mn, on an activated metal hydrous metal oxide support, such as HMO:Si. A promoter, such as tungsten oxide or molybdenum oxide, can be added and has been shown to increase conversion efficiency. This method provides good conversion of NO.sub.x to N.sub.2, good selectivity, good durability, resistance to SO.sub.2 aging and low toxicity compared with methods utilizing vanadia-based catalysts.

  1. Recent advances in optical measurement methods in physics and chemistry

    SciTech Connect

    Gerardo, J.B.

    1985-01-01

    Progress being made in the development of new scientific measurement tools based on optics and the scientific advances made possible by these new tools is impressive. In some instances, new optical-based measurement methods have made new scientific studies possible, while in other instances they have offered an improved method for performing these studies, e.g., better signal-to-noise ratio, increased data acquisition rate, remote analysis, reduced perturbation to the physical or chemical system being studied, etc. Many of these advances were made possible by advances in laser technology - spectral purity, spectral brightness, tunability, ultrashort pulse width, amplitude stability, etc. - while others were made possible by improved optical components - single-made fibers, modulators, detectors, wavelength multiplexes, etc. Attention is limited to just a few of many such accomplishments made recently at Sandia. 17 references, 16 figures.

  2. Advances in metal-induced oxidative stress and human disease.

    PubMed

    Jomova, Klaudia; Valko, Marian

    2011-05-10

    Detailed studies in the past two decades have shown that redox active metals like iron (Fe), copper (Cu), chromium (Cr), cobalt (Co) and other metals undergo redox cycling reactions and possess the ability to produce reactive radicals such as superoxide anion radical and nitric oxide in biological systems. Disruption of metal ion homeostasis may lead to oxidative stress, a state where increased formation of reactive oxygen species (ROS) overwhelms body antioxidant protection and subsequently induces DNA damage, lipid peroxidation, protein modification and other effects, all symptomatic for numerous diseases, involving cancer, cardiovascular disease, diabetes, atherosclerosis, neurological disorders (Alzheimer's disease, Parkinson's disease), chronic inflammation and others. The underlying mechanism of action for all these metals involves formation of the superoxide radical, hydroxyl radical (mainly via Fenton reaction) and other ROS, finally producing mutagenic and carcinogenic malondialdehyde (MDA), 4-hydroxynonenal (HNE) and other exocyclic DNA adducts. On the other hand, the redox inactive metals, such as cadmium (Cd), arsenic (As) and lead (Pb) show their toxic effects via bonding to sulphydryl groups of proteins and depletion of glutathione. Interestingly, for arsenic an alternative mechanism of action based on the formation of hydrogen peroxide under physiological conditions has been proposed. A special position among metals is occupied by the redox inert metal zinc (Zn). Zn is an essential component of numerous proteins involved in the defense against oxidative stress. It has been shown, that depletion of Zn may enhance DNA damage via impairments of DNA repair mechanisms. In addition, Zn has an impact on the immune system and possesses neuroprotective properties. The mechanism of metal-induced formation of free radicals is tightly influenced by the action of cellular antioxidants. Many low-molecular weight antioxidants (ascorbic acid (vitamin C), alpha

  3. 7 CFR 27.92 - Method of payment; advance deposit.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Method of payment; advance deposit. 27.92 Section 27.92 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD...

  4. METHODS ADVANCEMENT FOR MILK ANALYSIS: THE MAMA STUDY

    EPA Science Inventory

    The Methods Advancement for Milk Analysis (MAMA) study was designed by US EPA and CDC investigators to provide data to support the technological and study design needs of the proposed National Children=s Study (NCS). The NCS is a multi-Agency-sponsored study, authorized under the...

  5. Research Advances: Nitric Oxide Synthase Reduces Cr(VI); The Chemistry of Popcorn: It's All About "Pop-Ability"; Nanotubes May Help Heal Broken Bones; New Method Unites Organic Materials and Nanotechnology

    NASA Astrophysics Data System (ADS)

    King, Angela G.

    2005-12-01

    An enzyme can reduce chromium ions and increase toxicity. Chemistry may reduce the number of unpopped kernels. Nanotubes provide scaffolding for bone growth. A new method will aid fabrication of drug-delivery agents.

  6. Advanced propulsion for LEO-Moon transport. 1: A method for evaluating advanced propulsion performance

    NASA Technical Reports Server (NTRS)

    Stern, Martin O.

    1992-01-01

    This report describes a study to evaluate the benefits of advanced propulsion technologies for transporting materials between low Earth orbit and the Moon. A relatively conventional reference transportation system, and several other systems, each of which includes one advanced technology component, are compared in terms of how well they perform a chosen mission objective. The evaluation method is based on a pairwise life-cycle cost comparison of each of the advanced systems with the reference system. Somewhat novel and economically important features of the procedure are the inclusion not only of mass payback ratios based on Earth launch costs, but also of repair and capital acquisition costs, and of adjustments in the latter to reflect the technological maturity of the advanced technologies. The required input information is developed by panels of experts. The overall scope and approach of the study are presented in the introduction. The bulk of the paper describes the evaluation method; the reference system and an advanced transportation system, including a spinning tether in an eccentric Earth orbit, are used to illustrate it.

  7. Advances and future directions of research on spectral methods

    NASA Technical Reports Server (NTRS)

    Patera, A. T.

    1986-01-01

    Recent advances in spectral methods are briefly reviewed and characterized with respect to their convergence and computational complexity. Classical finite element and spectral approaches are then compared, and spectral element (or p-type finite element) approximations are introduced. The method is applied to the full Navier-Stokes equations, and examples are given of the application of the technique to several transitional flows. Future directions of research in the field are outlined.

  8. Innovative technical advances in the application of regenerative thermal oxidizers

    SciTech Connect

    Grzanka, R.; Truppi, T.

    1999-07-01

    Regenerative Thermal Oxidizers (RTOs) have been applied in industry for over twenty (20) years to reduce the emissions of Volatile Organic compounds (VOCs) into the atmosphere from industrial process emissions. The Clean Air Act and its amendments have established a regulatory framework setting standards for allowable levels of VOC emissions. Several forces are driving the increasing use and acceptance of this technology: (1) High efficiency and increasing stringent standards require higher destruction efficiency; (2) Low operating cost and control of emission streams with less VOCs (therefore, less fuel value) causing higher use of natural gas for combustion; (3) Low NO{sub x}--the overlapping concern of NO{sub x} generation from the combustion process; (4) Low process upsets with improved productivity of industrial process require continuous integration of VOC abatement equipment; and (5) Reduced capital cost--capital cost criteria is $/ton of VOC abated. The latest development in RTO technology is the Single Can Oxidizer (SCO). This regenerative thermal oxidizer is the accumulation of developments in many subsystems of RTOs, combined with a dramatic new configuration. Several features of the system offer unique benefits to industrial end users: (1) Single can configuration gives reduced weight, material usage, and cost; (2) Rotary valve design gives smooth operation, and low pressure fluctuations; (3) Structured block heat recovery media reduces pressure drop, and lowers HP/operating cost; and (4) SMART system lowers NO{sub x} output/reduced operation cost. This paper will present a discussion of the features listed above. In addition, it will provide analytical documentation of test results for a full scale commercial unit.

  9. Preliminary oxidation in histochemical staining methods for cholesterol.

    PubMed

    Adams, C W; High, O B

    1980-08-01

    The need for preliminary oxidation with histochemical methods for cholesterol was investigated on silica-coated sheets and in tissue sections. The techniques used were the Schultz reaction, perchloric acid-naphthoquinone (PAN), Lewis & Lobban's ferric alum-sulphuric acid reagent and Okamoto's iodine-sulphuric acid. The oxidants assessed were ferric chloride, ferric alum, potassium permanganate, ammonium sulphamate and ultraviolet light. The best combinations amongst those tested in order of reactivity were FeCl3-PAN, ferric alum-Schultz, Lewis-Lobban (no additional oxidant), iodine-sulphuric acid (no additional oxidant). Authentic preparations of cholesterol oxidation products were stained with these methods, but the nature of the oxidized product in the preliminary stage could not be determined. PMID:6157826

  10. Combined treatment technology based on synergism between hydrodynamic cavitation and advanced oxidation processes.

    PubMed

    Gogate, Parag R; Patil, Pankaj N

    2015-07-01

    The present work highlights the novel approach of combination of hydrodynamic cavitation and advanced oxidation processes for wastewater treatment. The initial part of the work concentrates on the critical analysis of the literature related to the combined approaches based on hydrodynamic cavitation followed by a case study of triazophos degradation using different approaches. The analysis of different combinations based on hydrodynamic cavitation with the Fenton chemistry, advanced Fenton chemistry, ozonation, photocatalytic oxidation, and use of hydrogen peroxide has been highlighted with recommendations for important design parameters. Subsequently degradation of triazophos pesticide in aqueous solution (20 ppm solution of commercially available triazophos pesticide) has been investigated using hydrodynamic cavitation and ozonation operated individually and in combination for the first time. Effect of different operating parameters like inlet pressure (1-8 bar) and initial pH (2.5-8) have been investigated initially. The effect of addition of Fenton's reagent at different loadings on the extent of degradation has also been investigated. The combined method of hydrodynamic cavitation and ozone has been studied using two approaches of injecting ozone in the solution tank and at the orifice (at the flow rate of 0.576 g/h and 1.95 g/h). About 50% degradation of triazophos was achieved by hydrodynamic cavitation alone under optimized operating parameters. About 80% degradation of triazophos was achieved by combination of hydrodynamic cavitation and Fenton's reagent whereas complete degradation was achieved using combination of hydrodynamic cavitation and ozonation. TOC removal of 96% was also obtained for the combination of ozone and hydrodynamic cavitation making it the best treatment strategy for removal of triazophos.

  11. Method of forming supported doped palladium containing oxidation catalysts

    SciTech Connect

    Mohajeri, Nahid

    2014-04-22

    A method of forming a supported oxidation catalyst includes providing a support comprising a metal oxide or a metal salt, and depositing first palladium compound particles and second precious metal group (PMG) metal particles on the support while in a liquid phase including at least one solvent to form mixed metal comprising particles on the support. The PMG metal is not palladium. The mixed metal particles on the support are separated from the liquid phase to provide the supported oxidation catalyst.

  12. Polyethylene Oxidation in Total Hip Arthroplasty: Evolution and New Advances

    PubMed Central

    Gómez-Barrena, Enrique; Medel, Francisco; Puértolas, José Antonio

    2009-01-01

    Ultra-high molecular weight polyethylene (UHMWPE) remains the gold standard acetabular bearing material for hip arthroplasty. Its successful performance has shown consistent results and survivorship in total hip replacement (THR) above 85% after 15 years, with different patients, surgeons, or designs. As THR results have been challenged by wear, oxidation, and liner fracture, relevant research on the material properties in the past decade has led to the development and clinical introduction of highly crosslinked polyethylenes (HXLPE). More stress on the bearing (more active, overweighted, younger patients), and more variability in the implantation technique in different small and large Hospitals may further compromise the clinical performance for many patients. The long-term in vivo performance of these materials remains to be proven. Clinical and retrieval studies after more than 5 years of in vivo use with HXLPE in THR are reviewed and consistently show a substantial decrease in wear rate. Moreover, a second generation of improved polyethylenes is backed by in vitro data and awaits more clinical experience to confirm the experimental improvements. Also, new antioxidant, free radical scavengers, candidates and the reinforcement of polyethylene through composites are currently under basic research. Oxidation of polyethylene is today significantly reduced by present formulations, and this forgiving, affordable, and wellknown material is still reliable to meet today’s higher requirements in total hip replacement. PMID:20111694

  13. Advances of vibrational spectroscopic methods in phytomics and bioanalysis.

    PubMed

    Huck, Christian W

    2014-01-01

    During the last couple of years great advances in vibrational spectroscopy including near-infrared (NIR), mid-infrared (MIR), attenuated total reflection (ATR) and imaging and also mapping techniques could be achieved. On the other hand spectral treatment features have improved dramatically allowing filtering out relevant information from spectral data much more efficiently and providing new insights into the biochemical composition. These advances offer new possible quality control strategies in phytomics and enable to get deeper insights into biochemical background in terms of medicinal relevant questions. It is the aim of the present article pointing out the technical and methodological advancements in the NIR and MIR field and to demonstrate the individual methods efficiency by discussing distinct selected applications.

  14. An advanced probabilistic structural analysis method for implicit performance functions

    NASA Technical Reports Server (NTRS)

    Wu, Y.-T.; Millwater, H. R.; Cruse, T. A.

    1989-01-01

    In probabilistic structural analysis, the performance or response functions usually are implicitly defined and must be solved by numerical analysis methods such as finite element methods. In such cases, the most commonly used probabilistic analysis tool is the mean-based, second-moment method which provides only the first two statistical moments. This paper presents a generalized advanced mean value (AMV) method which is capable of establishing the distributions to provide additional information for reliability design. The method requires slightly more computations than the second-moment method but is highly efficient relative to the other alternative methods. In particular, the examples show that the AMV method can be used to solve problems involving non-monotonic functions that result in truncated distributions.

  15. Advances in nucleic acid-based detection methods.

    PubMed Central

    Wolcott, M J

    1992-01-01

    Laboratory techniques based on nucleic acid methods have increased in popularity over the last decade with clinical microbiologists and other laboratory scientists who are concerned with the diagnosis of infectious agents. This increase in popularity is a result primarily of advances made in nucleic acid amplification and detection techniques. Polymerase chain reaction, the original nucleic acid amplification technique, changed the way many people viewed and used nucleic acid techniques in clinical settings. After the potential of polymerase chain reaction became apparent, other methods of nucleic acid amplification and detection were developed. These alternative nucleic acid amplification methods may become serious contenders for application to routine laboratory analyses. This review presents some background information on nucleic acid analyses that might be used in clinical and anatomical laboratories and describes some recent advances in the amplification and detection of nucleic acids. PMID:1423216

  16. Fracture Toughness in Advanced Monolithic Ceramics - SEPB Versus SEVENB Methods

    NASA Technical Reports Server (NTRS)

    Choi, S. R.; Gyekenyesi, J. P.

    2005-01-01

    Fracture toughness of a total of 13 advanced monolithic ceramics including silicon nitrides, silicon carbide, aluminas, and glass ceramic was determined at ambient temperature by using both single edge precracked beam (SEPB) and single edge v-notched beam (SEVNB) methods. Relatively good agreement in fracture toughness between the two methods was observed for advanced ceramics with flat R-curves; whereas, poor agreement in fracture toughness was seen for materials with rising R-curves. The discrepancy in fracture toughness between the two methods was due to stable crack growth with crack closure forces acting in the wake region of cracks even in SEVNB test specimens. The effect of discrepancy in fracture toughness was analyzed in terms of microstructural feature (grain size and shape), toughening exponent, and stable crack growth determined using back-face strain gaging.

  17. Development of an advanced bond coat for solid oxide fuel cell interconnector applications

    NASA Astrophysics Data System (ADS)

    Yeh, An-Chou; Chen, Yu-Ming; Liu, Chien-Kuo; Shong, Wei-Ja

    2015-11-01

    An advanced bond coat has been developed for solid oxide fuel cell interconnector applications; a low thermal expansion superalloy has been selected as the substrate, and the newly developed bond coat is applied between the substrate and the LSM top coat. The bond coat composition is designed to be near thermodynamic equilibrium with the substrate to minimize interdiffusion with the substrate while providing oxidation protection for the substrate. The bond coat exhibits good oxidation resistance, a low area specific resistance, and a low thermal expansion coefficient at 800 °C; experimental results indicate that interdiffusion between the bond coat and the substrate can be hindered.

  18. Formulation and method for preparing gels comprising hydrous aluminum oxide

    SciTech Connect

    Collins, Jack L.

    2014-06-17

    Formulations useful for preparing hydrous aluminum oxide gels contain a metal salt including aluminum, an organic base, and a complexing agent. Methods for preparing gels containing hydrous aluminum oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including aluminum, an organic base, and a complexing agent.

  19. Formulation and method for preparing gels comprising hydrous hafnium oxide

    SciTech Connect

    Collins, Jack L; Hunt, Rodney D; Montgomery, Frederick C

    2013-08-06

    Formulations useful for preparing hydrous hafnium oxide gels contain a metal salt including hafnium, an acid, an organic base, and a complexing agent. Methods for preparing gels containing hydrous hafnium oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including hafnium, an acid, an organic base, and a complexing agent.

  20. Formulation and method for preparing gels comprising hydrous cerium oxide

    DOEpatents

    Collins, Jack L; Chi, Anthony

    2013-05-07

    Formulations useful for preparing hydrous cerium oxide gels contain a metal salt including cerium, an organic base, and a complexing agent. Methods for preparing gels containing hydrous cerium oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including cerium, an organic base, and a complexing agent.

  1. Advanced stress analysis methods applicable to turbine engine structures

    NASA Technical Reports Server (NTRS)

    Pian, Theodore H. H.

    1991-01-01

    The following tasks on the study of advanced stress analysis methods applicable to turbine engine structures are described: (1) constructions of special elements which contain traction-free circular boundaries; (2) formulation of new version of mixed variational principles and new version of hybrid stress elements; (3) establishment of methods for suppression of kinematic deformation modes; (4) construction of semiLoof plate and shell elements by assumed stress hybrid method; and (5) elastic-plastic analysis by viscoplasticity theory using the mechanical subelement model.

  2. Improved method of HIPOT testing of advanced ignition system product

    SciTech Connect

    Baker, P.C.

    1992-04-01

    A new method of high potential (HIPOT) testing of advanced ignition system (AIS) product was developed. The new incorporated using a silver-filled RTV silicone as the electrodes of the HIPOT tester instead of the preformed, semi-rigid aluminum electrodes of the current tester. Initial results indicate that the developed method was more sensitive to the testing requirements of the HIPOT test. A patent for the combination of the material used and the method of testing developed was attempted but was withdrawn following a patent search by the US Patent Office.

  3. Method for preparing hydrous iron oxide gels and spherules

    DOEpatents

    Collins, Jack L.; Lauf, Robert J.; Anderson, Kimberly K.

    2003-07-29

    The present invention is directed to methods for preparing hydrous iron oxide spherules, hydrous iron oxide gels such as gel slabs, films, capillary and electrophoresis gels, iron monohydrogen phosphate spherules, hydrous iron oxide spherules having suspendable particles homogeneously embedded within to form composite sorbents and catalysts, iron monohydrogen phosphate spherules having suspendable particles of at least one different sorbent homogeneously embedded within to form a composite sorbent, iron oxide spherules having suspendable particles homogeneously embedded within to form a composite of hydrous iron oxide fiber materials, iron oxide fiber materials, hydrous iron oxide fiber materials having suspendable particles homogeneously embedded within to form a composite, iron oxide fiber materials having suspendable particles homogeneously embedded within to form a composite, dielectric spherules of barium, strontium, and lead ferrites and mixtures thereof, and composite catalytic spherules of barium or strontium ferrite embedded with oxides of Mg, Zn, Pb, Ce and mixtures thereof. These variations of hydrous iron oxide spherules and gel forms prepared by the gel-sphere, internal gelation process offer more useful forms of inorganic ion exchangers, catalysts, getters, dielectrics, and ceramics.

  4. Method and reaction pathway for selectively oxidizing organic compounds

    DOEpatents

    Camaioni, Donald M.; Lilga, Michael A.

    1998-01-01

    A method of selectively oxidizing an organic compound in a single vessel comprises: a) combining an organic compound, an acid solution in which the organic compound is soluble, a compound containing two oxygen atoms bonded to one another, and a metal ion reducing agent capable of reducing one of such oxygen atoms, and thereby forming a mixture; b) reducing the compound containing the two oxygen atoms by reducing one of such oxygen atoms with the metal ion reducing agent to, 1) oxidize the metal ion reducing agent to a higher valence state, and 2) produce an oxygen containing intermediate capable of oxidizing the organic compound; c) reacting the oxygen containing intermediate with the organic compound to oxidize the organic compound into an oxidized organic intermediate, the oxidized organic intermediate having an oxidized carbon atom; d) reacting the oxidized organic intermediate with the acid counter ion and higher valence state metal ion to bond the acid counter ion to the oxidized carbon atom and thereby produce a quantity of an ester incorporating the organic intermediate and acid counter ion; and e) reacting the oxidized organic intermediate with the higher valence state metal ion and water to produce a quantity of alcohol which is less than the quantity of ester, the acid counter ion incorporated in the ester rendering the carbon atom bonded to the counter ion less reactive with the oxygen containing intermediate in the mixture than is the alcohol with the oxygen containing intermediate.

  5. Method of making controlled morphology metal-oxides

    DOEpatents

    Ozcan, Soydan; Lu, Yuan

    2016-05-17

    A method of making metal oxides having a preselected morphology includes preparing a suspension that includes a solvent, polymeric nanostructures having multiplicities of hydroxyl surface groups and/or carboxyl surface groups, and a metal oxide precursor. The suspension has a preselected ratio of the polymeric nanostructures to the metal oxide precursor of at least 1:3, the preselected ratio corresponding to a preselected morphology. Subsequent steps include depositing the suspension onto a substrate, removing the solvent to form a film, removing the film from the substrate, and annealing the film to volatilize the polymeric nanostructures and convert the metal oxide precursor to metal oxide nanoparticles having the preselected morphology or to a metal oxide nanosheet including conjoined nanoparticles having the preselected morphology.

  6. Polyoxometalate water oxidation catalysts and methods of use thereof

    DOEpatents

    Hill, Craig L.; Gueletii, Yurii V.; Musaev, Djamaladdin G.; Yin, Qiushi; Botar, Bogdan

    2014-09-02

    Homogeneous water oxidation catalysts (WOCs) for the oxidation of water to produce hydrogen ions and oxygen, and methods of making and using thereof are described herein. In a preferred embodiment, the WOC is a polyoxometalate WOC which is hydrolytically stable, oxidatively stable, and thermally stable. The WOC oxidized waters in the presence of an oxidant. The oxidant can be generated photochemically, using light, such as sunlight, or electrochemically using a positively biased electrode. The hydrogen ions are subsequently reduced to form hydrogen gas, for example, using a hydrogen evolution catalyst (HEC). The hydrogen gas can be used as a fuel in combustion reactions and/or in hydrogen fuel cells. The catalysts described herein exhibit higher turn over numbers, faster turn over frequencies, and/or higher oxygen yields than prior art catalysts.

  7. Dietary advanced lipid oxidation endproducts are risk factors to human health.

    PubMed

    Kanner, Joseph

    2007-09-01

    Lipid oxidation in foods is one of the major degradative processes responsible for losses in food quality. The oxidation of unsaturated fatty acids results in significant generation of dietary advanced lipid oxidation endproducts (ALEs) which are in part cytotoxic and genotoxic compounds. The gastrointestinal tract is constantly exposed to dietary oxidized food compounds, after digestion a part of them are absorbed into the lymph or directly into the blood stream. After ingestion of oxidized fats animals and human have been shown to excrete in urine increase amounts of malondialdehyde but also lipophilic carbonyl compounds. Oxidized cholesterol in the diet was found to be a source of oxidized lipoproteins in human serum. Some of the dietary ALEs, which are absorbed from the gut to the circulatory system, seems to act as injurious chemicals that activate an inflammatory response which affects not only circulatory system but also organs such as liver, kidney, lung, and the gut itself. We believe that repeated consumption of oxidized fat in the diet poses a chronic threat to human health. High concentration of dietary antioxidants could prevent lipid oxidation and ALEs generation not only in foods but also in stomach condition and thereby potentially decrease absorption of ALEs from the gut. This could explains the health benefit of diets containing large amounts of dietary antioxidants such those present in fruits and vegetables, or products such as red-wine or tea consuming during the meal. PMID:17854006

  8. Dietary advanced lipid oxidation endproducts are risk factors to human health.

    PubMed

    Kanner, Joseph

    2007-09-01

    Lipid oxidation in foods is one of the major degradative processes responsible for losses in food quality. The oxidation of unsaturated fatty acids results in significant generation of dietary advanced lipid oxidation endproducts (ALEs) which are in part cytotoxic and genotoxic compounds. The gastrointestinal tract is constantly exposed to dietary oxidized food compounds, after digestion a part of them are absorbed into the lymph or directly into the blood stream. After ingestion of oxidized fats animals and human have been shown to excrete in urine increase amounts of malondialdehyde but also lipophilic carbonyl compounds. Oxidized cholesterol in the diet was found to be a source of oxidized lipoproteins in human serum. Some of the dietary ALEs, which are absorbed from the gut to the circulatory system, seems to act as injurious chemicals that activate an inflammatory response which affects not only circulatory system but also organs such as liver, kidney, lung, and the gut itself. We believe that repeated consumption of oxidized fat in the diet poses a chronic threat to human health. High concentration of dietary antioxidants could prevent lipid oxidation and ALEs generation not only in foods but also in stomach condition and thereby potentially decrease absorption of ALEs from the gut. This could explains the health benefit of diets containing large amounts of dietary antioxidants such those present in fruits and vegetables, or products such as red-wine or tea consuming during the meal.

  9. TiO2-Based Advanced Oxidation Nanotechnologies For Water Purification And Reuse

    EPA Science Inventory

    TiO2 photocatalysis, one of the UV-based advanced oxidation technologies (AOTs) and nanotechnologies (AONs), has attracted great attention for the development of efficient water treatment and purification systems due to the effectiveness of TiO2 to generate ...

  10. DEMONSTRATION OF THE HIPOX ADVANCED OXIDATION TECHNOLOGY FOR THE TREATMENT OF MTBE-CONTAMINATED GROUNDWATER

    EPA Science Inventory

    The HiPOx technology is an advanced oxidation process that incorporates high-precision delivery of ozone and hydrogen peroxide to chemically destroy organic contaminants with the promise of minimizing bromate formation. A MTBE-contaminated groundwater from the Ventura County Nav...

  11. DESTRUCTION OF PAHS AND PCBS IN WATER USING SULFATE RADICAL-BASED CATALYTIC ADVANCED OXIDATION PROCESSES

    EPA Science Inventory

    A new class of advanced oxidation processes (AOPs) based on sulfate radicals is being tested for the degradation of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in aqueous solution. These AOPs are based on the generation of sulfate radicals through...

  12. Differential oxidative status and immune characterization of the early and advanced stages of human breast cancer.

    PubMed

    Panis, C; Victorino, V J; Herrera, A C S A; Freitas, L F; De Rossi, T; Campos, F C; Simão, A N Colado; Barbosa, D S; Pinge-Filho, P; Cecchini, R; Cecchini, A L

    2012-06-01

    Breast cancer is the malignant neoplasia with the highest incidence in women worldwide. Chronic oxidative stress and inflammation have been indicated as major mediators during carcinogenesis and cancer progression. Human studies have not considered the complexity of tumor biology during the stages of cancer advance, limiting their clinical application. The purpose of this study was to characterize systemic oxidative stress and immune response parameters in early (ED; TNM I and II) and advanced disease (AD; TNM III and IV) of patients diagnosed with infiltrative ductal carcinoma breast cancer. Oxidative stress parameters were evaluated by plasmatic lipoperoxidation, carbonyl content, thiobarbituric reactive substances (TBARS), nitric oxide levels (NO), total radical antioxidant parameter (TRAP), superoxide dismutase, and catalase activities and GSH levels. Immune evaluation was determined by TNF-α, IL-1β, IL-12, and IL-10 levels and leukocytes oxidative burst evaluation by chemiluminescence. Tissue damage analysis included heart (total CK and CKMB), liver (AST, ALT, GGT), and renal (creatinine, urea, and uric acid) plasmatic markers. C-reactive protein (CRP) and iron metabolism were also evaluated. Analysis of the results verified different oxidative stress statuses occur at distinct cancer stages. ED was characterized by reduction in catalase, 8-isoprostanes, and GSH levels, with enhanced lipid peroxidation and TBARS levels. AD exhibited more pronounced oxidative status, with reduction in catalase activity and TRAP, intense lipid peroxidation and high levels of NO, TBARs, and carbonyl content. ED patients presented a Th2 immune pattern, while AD exhibited Th1 status. CRP levels and ferritin were increased in both stages of disease. Leukocytes burst impairment was observed in both the groups. Plasma iron levels were significantly elevated in AD. The data obtained indicated that oxidative stress enhancement and immune response impairment may be necessary to ensure

  13. A new method for oxidation of gaseous, elemental mercury.

    SciTech Connect

    Livengood, C. D.; Mendelsohn, M. H.

    1999-08-23

    Elemental mercury (Hg) is difficult to remove from flue-gas streams using existing wet-scrubber technology, primarily because of its limited volubility in water. We have proposed and tested a concept for enhancing gaseous Hg{sup 0}removal in wet scrubber systems by altering the chemical form of the Hg{sup 0} to a water-soluble oxidized species. Recently, we have discovered a new method for injection of the oxidizing species that dramatically improves reactant utilization and at the same time gives significant nitric oxide (NO) oxidation as well. Our method uses a diluted oxidizing solution containing chloric acid and sodium chlorate (sold commercially as NOXSORB{trademark}). When this solution is injected into a gas stream containing Hg{sup 0} at about 300 F, we found that nearly 100% of the Hg{sup 0} was removed from the gas phase and was recovered in liquid samples from the test system. At the same time, approximately 80% of the added NO was also removed (oxidized). The effect of sulfur dioxide (SO{sub 2}) on this method was also investigated, and it appears to decrease slightly the amount of Hg oxidized. We are currently testing the effect of variations in oxidizing solution concentration, SO{sub 2} concentration, NO concentration, and reaction time (residence time).

  14. Treatment of petroleum refinery sourwater by advanced oxidation processes.

    PubMed

    Coelho, Alessandra; Castro, Antonio V; Dezotti, Márcia; Sant'Anna, G L

    2006-09-01

    The performance of several oxidation processes to remove organic pollutants from sourwater was investigated. Sourwater is a specific stream of petroleum refineries, which contains slowly biodegradable compounds and toxic substances that impair the industrial biological wastewater treatment system. Preliminary experiments were conducted, using the following processes: H2O2, H2O2/UV, UV, photocatalysis, ozonation, Fenton and photo-Fenton. All processes, except Fenton and photo-Fenton, did not lead to satisfactory results, reducing at most 35% of the sourwater dissolved organic carbon (DOC). Thus, further experiments were performed with these two techniques to evaluate process conditions and organic matter removal kinetics. Batch experiments revealed that the Fenton reaction is very fast and reaches, in a few minutes, an ultimate DOC removal of 13-27%, due to the formation of iron complexes. Radiation for an additional period of 60 min can increase DOC removal up to 87%. Experiments were also conducted in a continuous mode, operating one 0.4L Fenton stirred reactor and one 1.6L photo-Fenton reactor in series. DOC removals above 75% were reached, when the reaction system was operated with hydraulic retention times (HRT) higher than 85 min. An empirical mathematical model was proposed to represent the DOC removal kinetics, allowing predicting process performance quite satisfactorily.

  15. Advances in Understanding the Actions of Nitrous Oxide

    PubMed Central

    Emmanouil, Dimitris E; Quock, Raymond M

    2007-01-01

    Nitrous oxide (N2O) has been used for well over 150 years in clinical dentistry for its analgesic and anxiolytic properties. This small and simple inorganic chemical molecule has indisputable effects of analgesia, anxiolysis, and anesthesia that are of great clinical interest. Recent studies have helped to clarify the analgesic mechanisms of N2O, but the mechanisms involved in its anxiolytic and anesthetic actions remain less clear. Findings to date indicate that the analgesic effect of N2O is opioid in nature, and, like morphine, may involve a myriad of neuromodulators in the spinal cord. The anxiolytic effect of N2O, on the other hand, resembles that of benzodiazepines and may be initiated at selected subunits of the γ-aminobutyric acid type A (GABAA) receptor. Similarly, the anesthetic effect of N2O may involve actions at GABAA receptors and possibly at N-methyl-D-aspartate receptors as well. This article reviews the latest information on the proposed modes of action for these clinicaleffects of N2O. PMID:17352529

  16. Manganese oxide nanowires, films, and membranes and methods of making

    DOEpatents

    Suib, Steven Lawrence; Yuan, Jikang

    2011-02-15

    Nanowires, films, and membranes comprising ordered porous manganese oxide-based octahedral molecular sieves and methods of making the same are disclosed. A method for forming nanowires includes hydrothermally treating a chemical precursor composition in a hydrothermal treating solvent to form the nanowires, wherein the chemical precursor composition comprises a source of manganese cations and a source of counter cations, and wherein the nanowires comprise ordered porous manganese oxide-based octahedral molecular sieves.

  17. Mineralization of paracetamol in aqueous solution with advanced oxidation processes.

    PubMed

    Torun, Murat; Gültekin, Özge; Şolpan, Dilek; Güven, Olgun

    2015-01-01

    Paracetamol is a common analgesic drug widely used in all regions of the world more than hundred tonnes per year and it poses a great problem for the aquatic environment. Its phenolic intermediates are classified as persistent organic pollutants and toxic for the environment as well as human beings. In the present study, the irradiation of aqueous solutions of paracetamol with 60Co gamma-rays was examined on a laboratory scale and its degradation path was suggested with detected radiolysis products. The synergic effect of ozone on gamma-irradiation was investigated by preliminary ozonation before irradiation which reduced the irradiation dose from 5 to 3 kGy to completely remove paracetamol and its toxic intermediate hydroquinone from 6 to 4 kGy as well as increasing the radiation chemical yield (Gi values 1.36 and 1.66 in the absence and presence of ozone, respectively). The observed amount of formed hydroquinone was also decreased in the presence of ozone. There is a decrease in pH from 6.4 to 5.2 and dissolved oxygen consumed, which is up to 0.8 mg l(-1), to form some peroxyl radicals used for oxidation. Analytical measurements were carried out with gas chromatography/mass spectrometry and ion chromatography (IC) both qualitatively and quantitatively. Amounts of paracetamol and hydroquinone were measured with gas chromatography after trimethylsilane derivatization. Small aliphatic acids, such as acetic acid, formic acid and oxalic acid, were measured quantitatively with IC as well as inorganic ions (nitrite and nitrate) in which their yields increase with irradiation.

  18. Mineralization of paracetamol in aqueous solution with advanced oxidation processes.

    PubMed

    Torun, Murat; Gültekin, Özge; Şolpan, Dilek; Güven, Olgun

    2015-01-01

    Paracetamol is a common analgesic drug widely used in all regions of the world more than hundred tonnes per year and it poses a great problem for the aquatic environment. Its phenolic intermediates are classified as persistent organic pollutants and toxic for the environment as well as human beings. In the present study, the irradiation of aqueous solutions of paracetamol with 60Co gamma-rays was examined on a laboratory scale and its degradation path was suggested with detected radiolysis products. The synergic effect of ozone on gamma-irradiation was investigated by preliminary ozonation before irradiation which reduced the irradiation dose from 5 to 3 kGy to completely remove paracetamol and its toxic intermediate hydroquinone from 6 to 4 kGy as well as increasing the radiation chemical yield (Gi values 1.36 and 1.66 in the absence and presence of ozone, respectively). The observed amount of formed hydroquinone was also decreased in the presence of ozone. There is a decrease in pH from 6.4 to 5.2 and dissolved oxygen consumed, which is up to 0.8 mg l(-1), to form some peroxyl radicals used for oxidation. Analytical measurements were carried out with gas chromatography/mass spectrometry and ion chromatography (IC) both qualitatively and quantitatively. Amounts of paracetamol and hydroquinone were measured with gas chromatography after trimethylsilane derivatization. Small aliphatic acids, such as acetic acid, formic acid and oxalic acid, were measured quantitatively with IC as well as inorganic ions (nitrite and nitrate) in which their yields increase with irradiation. PMID:25263253

  19. Electrochemically Deposited Ceria Structures for Advanced Solid Oxide Fuel Cells

    NASA Astrophysics Data System (ADS)

    Brown, Evan C.

    As the pursuit towards emissions reduction intensifies with growing interest and nascent technologies, solid oxide fuel cells (SOFCs) remain an illustrious candidate for achieving our goals. Despite myriad advantages, SOFCs are still too costly for widespread deployment, even as unprecedented materials developments have recently emerged. This suggests that, in addition to informed materials selection, the necessary power output--and, thereby, cost-savings--gains must come from the fuel cell architecture. The work presented in this manuscript primarily investigates cathodic electrochemical deposition (CELD) as a scalable micro-/nanoscale fabrication tool for engineering ceria-based components in a SOFC assembly. Also, polymer sphere lithography was utilized to deposit fully connected, yet fully porous anti-dot metal films on yttira-stabilized zirconia (YSZ) with specific and knowable geometries, useful for mechanistic studies. Particular attention was given to anode structures, for which anti-dot metal films on YSZ served as composite substrates for subsequent CELD of doped ceria. By tuning the applied potential, a wide range of microstructures from high surface area coatings to planar, thin films was possible. In addition, definitive deposition was shown to occur on the electronically insulating YSZ surfaces, producing quality YSZ|ceria interfaces. These CELD ceria deposits exhibited promising electrochemical activity, as probed by A.C. Impedance Spectroscopy. In an effort to extend its usefulness as a SOFC fabrication tool, the CELD of ceria directly onto common SOFC cathode materials without a metallic phase was developed, as well as templated deposition schemes producing ceria nanowires and inverse opals.

  20. Advanced alternate planar geometry solid oxide fuel cells. Final report

    SciTech Connect

    Elangovan, S.; Prouse, D.; Khandkar, A.; Donelson, R.; Marianowski, L.

    1992-11-01

    The potential of high temperature Solid Oxide Fuel Cells as high performance, high efficiency energy conversion device is well known. Investigation of several cell designs have been undertaken by various researchers to derive the maximum performance benefit from the device while maintaining a lower cost of production to meet the commercialization cost target. The present investigation focused on the planar SOFC design which allows for the use of mature low cost production processes to be employed. A novel design concept was investigated which allows for improvements in performance through increased interface stability, and lowering of cost through enhanced structural integrity and the use of low cost metal interconnects. The new cell design consisted of a co-sintered porous/dense/porous zirconia layer with the electrode material infiltrated into the porous layers. The two year program conducted by a team involving Ceramatec and the Institute of Gas Technology, culminated in a multi-cell stack test that exhibited high performance. Considerable progress was achieved in the selection of cell components, and establishing and optimizing the cell and stack fabrication parameters. It was shown that the stack components exhibited high conductivities and low creep at the operating temperature. The inter-cell resistive losses were shown to be small through out-of-cell characterization. The source of performance loss was identified to be the anode electrolyte interface. This loss however can be minimized by improving the anode infiltration technique. Manifolding and sealing of the planar devices posed considerable challenge. Even though the open circuit voltage was 250 mV/cell lower than theoretical, the two cell stack had a performance of 300 mA/cm{sup 2} at 0.4V/cell with an area specific resistance of 1 {Omega}-cm{sup 2}/cell. improvements in manifolding are expected to provide much higher performance.

  1. Advanced alternate planar geometry solid oxide fuel cells

    SciTech Connect

    Elangovan, S.; Prouse, D.; Khandkar, A.; Donelson, R.; Marianowski, L. )

    1992-11-01

    The potential of high temperature Solid Oxide Fuel Cells as high performance, high efficiency energy conversion device is well known. Investigation of several cell designs have been undertaken by various researchers to derive the maximum performance benefit from the device while maintaining a lower cost of production to meet the commercialization cost target. The present investigation focused on the planar SOFC design which allows for the use of mature low cost production processes to be employed. A novel design concept was investigated which allows for improvements in performance through increased interface stability, and lowering of cost through enhanced structural integrity and the use of low cost metal interconnects. The new cell design consisted of a co-sintered porous/dense/porous zirconia layer with the electrode material infiltrated into the porous layers. The two year program conducted by a team involving Ceramatec and the Institute of Gas Technology, culminated in a multi-cell stack test that exhibited high performance. Considerable progress was achieved in the selection of cell components, and establishing and optimizing the cell and stack fabrication parameters. It was shown that the stack components exhibited high conductivities and low creep at the operating temperature. The inter-cell resistive losses were shown to be small through out-of-cell characterization. The source of performance loss was identified to be the anode electrolyte interface. This loss however can be minimized by improving the anode infiltration technique. Manifolding and sealing of the planar devices posed considerable challenge. Even though the open circuit voltage was 250 mV/cell lower than theoretical, the two cell stack had a performance of 300 mA/cm[sup 2] at 0.4V/cell with an area specific resistance of 1 [Omega]-cm[sup 2]/cell. improvements in manifolding are expected to provide much higher performance.

  2. Removal of natural organic matter from drinking water by advanced oxidation processes.

    PubMed

    Matilainen, Anu; Sillanpää, Mika

    2010-06-01

    Over the past 10-20years the amount of the natural organic matter (NOM) has been increased in raw water supplies on several areas. The presence of NOM causes many problems in drinking water treatment processes, including: (i) negative effect on water quality by colour, taste and odor problems, (ii) increased coagulant and disinfectant dose requirements (which in turn results increased sludge and potential harmful disinfection by-product formation), (iii) promoted biological growth in distribution system, and (iv) increased levels of complexed heavy metals and adsorbed organic pollutants. Thus, more efficient methods for the removal of NOM have emerged. Among these are advanced oxidation processes (AOPs). These include O(3)/H(2)O(2), O(3)/UV, UV/H(2)O(2), TiO(2)/UV, H(2)O(2)/catalyst, Fenton and photo-Fenton prosesses as well as ultrasound. In the present work, an overview of the recent research studies dealing with AOP methods for the removal of NOM and related compounds from drinking water is presented.

  3. Advances in Statistical Methods for Substance Abuse Prevention Research

    PubMed Central

    MacKinnon, David P.; Lockwood, Chondra M.

    2010-01-01

    The paper describes advances in statistical methods for prevention research with a particular focus on substance abuse prevention. Standard analysis methods are extended to the typical research designs and characteristics of the data collected in prevention research. Prevention research often includes longitudinal measurement, clustering of data in units such as schools or clinics, missing data, and categorical as well as continuous outcome variables. Statistical methods to handle these features of prevention data are outlined. Developments in mediation, moderation, and implementation analysis allow for the extraction of more detailed information from a prevention study. Advancements in the interpretation of prevention research results include more widespread calculation of effect size and statistical power, the use of confidence intervals as well as hypothesis testing, detailed causal analysis of research findings, and meta-analysis. The increased availability of statistical software has contributed greatly to the use of new methods in prevention research. It is likely that the Internet will continue to stimulate the development and application of new methods. PMID:12940467

  4. Optimization of stabilized leachate treatment using ozone/persulfate in the advanced oxidation process

    SciTech Connect

    Abu Amr, Salem S.; Aziz, Hamidi Abdul; Adlan, Mohd Nordin

    2013-06-15

    Highlights: ► Ozone and persulfate reagent (O{sub 3}/S{sub 2}O{sub 8}{sup 2-}) was used to treat stabilized leachate. ► Central composite design (CCD) with response surface methodology (RSM) was applied. ► Operating variables including ozone and persulfate dosage, pH variance, and reaction time. ► Optimum removal of COD, color, and NH{sub 3}–N was 72%, 96%, and 76%, respectively. ► A good value of ozone consumption (OC) obtained with 0.60 (kg O{sub 3}/kg COD). - Abstract: The objective of this study was to investigate the performance of employing persulfate reagent in the advanced oxidation of ozone to treat stabilized landfill leachate in an ozone reactor. A central composite design (CCD) with response surface methodology (RSM) was applied to evaluate the relationships between operating variables, such as ozone and persulfate dosages, pH, and reaction time, to identify the optimum operating conditions. Quadratic models for the following four responses proved to be significant with very low probabilities (<0.0001): COD, color, NH{sub 3}–N, and ozone consumption (OC). The obtained optimum conditions included a reaction time of 210 min, 30 g/m{sup 3} ozone, 1 g/1 g COD{sub 0}/S{sub 2}O{sub 8}{sup 2-} ratio, and pH 10. The experimental results were corresponded well with predicted models (COD, color, and NH{sub 3}–N removal rates of 72%, 96%, and 76%, respectively, and 0.60 (kg O{sub 3}/kg COD OC). The results obtained in the stabilized leachate treatment were compared with those from other treatment processes, such as ozone only and persulfate S{sub 2}O{sub 8}{sup 2-} only, to evaluate its effectiveness. The combined method (i.e., O{sub 3}/S{sub 2}O{sub 8}{sup 2-}) achieved higher removal efficiencies for COD, color, and NH{sub 3}–N compared with other studied applications. Furthermore, the new method is more efficient than ozone/Fenton in advanced oxidation process in the treatment of the same studied leachate.

  5. Application of Vacuum Deposition Methods to Solid Oxide Fuel Cells

    SciTech Connect

    Pederson, Larry R.; Singh, Prabhakar; Zhou, Xiao Dong

    2006-07-01

    The application of vacuum deposition techniques to the fabrication of solid oxide fuel cell materials and structures are reviewed, focusing on magnetron sputtering, vacuum plasma methods, laser ablation, and electrochemical vapor deposition. A description of each method and examples of use to produce electrolyte, electrode, and/or electrical interconnects are given. Generally high equipment costs and relatively low deposition rates have limited the use of vacuum deposition methods in solid oxide fuel cell manufacture, with a few notable exceptions. Vacuum methods are particularly promising in the fabrication of micro fuel cells, where thin films of high quality and unusual configuration are desired.

  6. Niobium oxide compositions and methods for using same

    DOEpatents

    Goodenough, John B; Han, Jian-Tao

    2014-02-11

    The disclosure relates a niobium oxide useful in anodes of secondary lithium ion batteries. Such niobium oxide has formula Li.sub.xM.sub.1-yNb.sub.yNb.sub.2O.sub.7, wherein 0.ltoreq.x.ltoreq.3, 0.ltoreq.y.ltoreq.1, and M represents Ti or Zr. The niobium oxide may be in the form of particles, which may be carbon coated. The disclosure also relates to an electrode composition containing at least one or more niobium oxides of formula Li.sub.xM.sub.1-yNb.sub.yNb.sub.2O.sub.7. The disclosure further relates to electrodes, such as anodes, and batteries containing at least one or more niobium oxides of formula Li.sub.xM.sub.1-yNb.sub.yNb.sub.2O.sub.7. Furthermore, the disclosure relates to methods of forming the above.

  7. Oxygen Penalty for Waste Oxidation in an Advanced Life Support System: A Systems Approach

    NASA Technical Reports Server (NTRS)

    Pisharody, Suresh; Wignarajah, K.; Fisher, John

    2002-01-01

    Oxidation is one of a number of technologies that are being considered for waste management and resource recovery from waste materials generated on board space missions. Oxidation processes are a very effective and efficient means of clean and complete conversion of waste materials to sterile products. However, because oxidation uses oxygen there is an "oxygen penalty" associated either with resupply of oxygen or with recycling oxygen from some other source. This paper is a systems approach to the issue of oxygen penalty in life support systems and presents findings on the oxygen penalty associated with an integrated oxidation-Sabatier-Oxygen Generation System (OGS) for waste management in an Advanced Life Support System. The findings reveal that such an integrated system can be operated to form a variety of useful products without a significant oxygen penalty.

  8. Rational design of metal oxide nanocomposite anodes for advanced lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Li, Yong; Yu, Shenglan; Yuan, Tianzhi; Yan, Mi; Jiang, Yinzhu

    2015-05-01

    Metal-oxide anodes represent a significant future direction for advanced lithium ion batteries. However, their practical applications are still seriously hampered by electrode disintegration and capacity fading during cycling. Here, we report a rational design of 3D-staggered metal-oxide nanocomposite electrode directly fabricated by pulsed spray evaporation chemical vapor deposition, where various oxide nanocomponents are in a staggered distribution uniformly along three dimensions and across the whole electrode. Such a special design of nanoarchitecture combines the advantages of nanoscale materials in volume change and Li+/electron conduction as well as uniformly staggered and compact structure in atom migration during lithiation/delithiation, which exhibits high specific capacity, good cycling stability and excellent rate capability. The rational design of metal-oxide nanocomposite electrode opens up new possibilities for high performance lithium ion batteries.

  9. Method of texturing a superconductive oxide precursor

    DOEpatents

    DeMoranville, Kenneth L.; Li, Qi; Antaya, Peter D.; Christopherson, Craig J.; Riley, Jr., Gilbert N.; Seuntjens, Jeffrey M.

    1999-01-01

    A method of forming a textured superconductor wire includes constraining an elongated superconductor precursor between two constraining elongated members placed in contact therewith on opposite sides of the superconductor precursor, and passing the superconductor precursor with the two constraining members through flat rolls to form the textured superconductor wire. The method includes selecting desired cross-sectional shape and size constraining members to control the width of the formed superconductor wire. A textured superconductor wire formed by the method of the invention has regular-shaped, curved sides and is free of flashing. A rolling assembly for single-pass rolling of the elongated precursor superconductor includes two rolls, two constraining members, and a fixture for feeding the precursor superconductor and the constraining members between the rolls. In alternate embodiments of the invention, the rolls can have machined regions which will contact only the elongated constraining members and affect the lateral deformation and movement of those members during the rolling process.

  10. Advanced oxidation-resistant iron-based alloys for LWR fuel cladding

    NASA Astrophysics Data System (ADS)

    Terrani, K. A.; Zinkle, S. J.; Snead, L. L.

    2014-05-01

    Application of advanced oxidation-resistant iron alloys as light water reactor fuel cladding is proposed. The motivations are based on specific limitations associated with zirconium alloys, currently used as fuel cladding, under design-basis and beyond-design-basis accident scenarios. Using a simplified methodology, gains in safety margins under severe accidents upon transition to advanced oxidation-resistant iron alloys as fuel cladding are showcased. Oxidation behavior, mechanical properties, and irradiation effects of advanced iron alloys are briefly reviewed and compared to zirconium alloys as well as historic austenitic stainless steel cladding materials. Neutronic characteristics of iron-alloy-clad fuel bundles are determined and fed into a simple economic model to estimate the impact on nuclear electricity production cost. Prior experience with steel cladding is combined with the current understanding of the mechanical properties and irradiation behavior of advanced iron alloys to identify a combination of cladding thickness reduction and fuel enrichment increase (∼0.5%) as an efficient route to offset any penalties in cycle length, due to higher neutron absorption in the iron alloy cladding, with modest impact on the economics.

  11. Biological efficacy and toxic effect of emergency water disinfection process based on advanced oxidation technology.

    PubMed

    Tian, Yiping; Yuan, Xiaoli; Xu, Shujing; Li, Rihong; Zhou, Xinying; Zhang, Zhitao

    2015-12-01

    An innovative and removable water treatment system consisted of strong electric field discharge and hydrodynamic cavitation based on advanced oxidation technologies was developed for reactive free radicals producing and waterborne pathogens eliminating in the present study. The biological efficacy and toxic effects of this advanced oxidation system were evaluated during water disinfection treatments. Bench tests were carried out with synthetic microbial-contaminated water, as well as source water in rainy season from a reservoir of Dalian city (Liaoning Province, China). Results showed that high inactivation efficiency of Escherichia coli (>5 log) could be obtained for synthetic contaminated water at a low concentration (0.5-0.7 mg L(-1)) of total oxidants in 3-10 s. The numbers of wild total bacteria (108 × 10(3) CFU mL(-1)) and total coliforms (260 × 10(2) MPN 100 mL(-1)) in source water greatly reduced to 50 and 0 CFU mL(-1) respectively after treated by the advanced oxidation system, which meet the microbiological standards of drinking water, and especially that the inactivation efficiency of total coliforms could reach 100%. Meanwhile, source water qualities were greatly improved during the disinfection processes. The values of UV254 in particular were significantly reduced (60-80%) by reactive free radicals. Moreover, the concentrations of possible disinfection by-products (formaldehyde and bromide) in treated water were lower than detection limits, indicating that there was no harmful effect on water after the treatments. These investigations are helpful for the ecotoxicological studies of advanced oxidation system in the treatments of chemical polluted water or waste water. The findings of this work suggest that the developed water treatment system is ideal in the acute phases of emergencies, which also could offer additional advantages over a wide range of applications in water pollution control.

  12. Apparatus and method for two-stage oxidation of wastes

    DOEpatents

    Fleischman, Scott D.

    1995-01-01

    An apparatus and method for oxidizing wastes in a two-stage process. The apparatus includes an oxidation device, a gas-liquid contacting column and an electrocell. In the first stage of the process, wastes are heated in the presence of air to partially oxidize the wastes. The heated wastes produce an off-gas stream containing oxidizable materials. In the second stage, the off-gas stream is cooled and flowed through the contacting column, where the off-gas stream is contacted with an aqueous acid stream containing an oxidizing agent having at least two positive valence states. At least a portion of the oxidizable materials are transferred to the acid stream and destroyed by the oxidizing agent. During oxidation, the valence of the oxidizing agent is decreased from its higher state to its lower state. The acid stream is flowed to the electrocell, where an electric current is applied to the stream to restore the oxidizing agent to its higher valence state. The regenerated acid stream is recycled to the contacting column.

  13. Method of physical vapor deposition of metal oxides on semiconductors

    DOEpatents

    Norton, David P.

    2001-01-01

    A process for growing a metal oxide thin film upon a semiconductor surface with a physical vapor deposition technique in a high-vacuum environment and a structure formed with the process involves the steps of heating the semiconductor surface and introducing hydrogen gas into the high-vacuum environment to develop conditions at the semiconductor surface which are favorable for growing the desired metal oxide upon the semiconductor surface yet is unfavorable for the formation of any native oxides upon the semiconductor. More specifically, the temperature of the semiconductor surface and the ratio of hydrogen partial pressure to water pressure within the vacuum environment are high enough to render the formation of native oxides on the semiconductor surface thermodynamically unstable yet are not so high that the formation of the desired metal oxide on the semiconductor surface is thermodynamically unstable. Having established these conditions, constituent atoms of the metal oxide to be deposited upon the semiconductor surface are directed toward the surface of the semiconductor by a physical vapor deposition technique so that the atoms come to rest upon the semiconductor surface as a thin film of metal oxide with no native oxide at the semiconductor surface/thin film interface. An example of a structure formed by this method includes an epitaxial thin film of (001)-oriented CeO.sub.2 overlying a substrate of (001) Ge.

  14. Apparatus and method for two-stage oxidation of wastes

    SciTech Connect

    Fleischman, S.D.

    1993-09-28

    An apparatus and method for oxidizing wastes in a two-stage process. The apparatus includes an oxidation device, a gas-liquid contacting column and an electrocell. In the first stage of the process, wastes are heated in the presence of air to partially oxidize the wastes. The heated wastes produce an off-gas stream containing oxidizable materials. In the second stage, the off-gas stream is cooled and flowed through the contacting column, where the off-gas stream is contacted with an aqueous acid stream containing an oxidizing agent having at least two positive valence states. At least a portion of the oxidizable materials are transferred to the acid stream and destroyed by the oxidizing agent. During oxidation, the valence of the oxidizing agent is decreased from its higher state to its lower state. The acid stream is flowed to the electrocell, where an electric current is applied to the stream to restore the oxidizing agent to its higher valence state. The regenerated acid stream is recycled to the contacting column.

  15. Nitro-oxidative species in vivo biosensing: challenges and advances with focus on peroxynitrite quantification.

    PubMed

    Peteu, Serban F; Boukherroub, Rabah; Szunerits, Sabine

    2014-08-15

    The importance of the so-called reactive nitrogen and oxygen species (RNOS) in biology and food technology has been widely recognized. However when these species are in excess, the steady-state maintained by physiological processes is disturbed. At this point, the nitro oxidative metabolic stress develops and its action in vivo over time leads to nitro-oxidative reactions in food and in living organisms, but also results in chronic degenerative diseases. Analytical methods enabling the assessment of the total antioxidant activity of a biological sample or a plant extract is therefore largely sought after. The ability of biosensors for rapid and real-time analysis that decreases the assay time and the possibility of automated and multi-analyte analysis at low cost has also allowed the quantitative and qualitative detection of RNOS. Among these RNOS, peroxynitrite (ONOO(-)) is a well-known inflammatory mediator during a number of physiological and pathological processes. Consequently, many efforts are underway to detect peroxynitrite in the biomedical field. This urgent demand makes the development of ONOO(-) specific probes of great interest. Not only they can be useful for the detection of disease states, but they will also allow for a screening-type analysis of potential signal transduction pathways in the cells. This invited review will critically discuss for the first time the very latest advancements and the challenges in the field of peroxynitrite biosensors and probes for in vivo and in vitro studies. Also, the main trends will be extracted, in order to chart the future directions and hence create an instrumental outlook.

  16. Efficient removal of insecticide "imidacloprid" from water by electrochemical advanced oxidation processes.

    PubMed

    Turabik, Meral; Oturan, Nihal; Gözmen, Belgin; Oturan, Mehmet A

    2014-01-01

    The oxidative degradation of imidacloprid (ICP) has been carried out by electrochemical advanced oxidation processes (EAOPs), anodic oxidation, and electro-Fenton, in which hydroxyl radicals are generated electrocatalytically. Carbon-felt cathode and platinum or boron-doped diamond (BDD) anodes were used in electrolysis cell. To determine optimum operating conditions, the effects of applied current and catalyst concentration were investigated. The decay of ICP during the oxidative degradation was well fitted to pseudo-first-order reaction kinetics and absolute rate constant of the oxidation of ICP by hydroxyl radicals was found to be k abs(ICP) = 1.23 × 10(9) L mol(-1) s(-1). The results showed that both anodic oxidation and electro-Fenton process with BDD anode exhibited high mineralization efficiency reaching 91 and 94% total organic carbon (TOC) removal at 2 h, respectively. For Pt-EF process, mineralization efficiency was also obtained as 71%. The degradation products of ICP were identified and a plausible general oxidation mechanism was proposed. Some of the main reaction intermediates such as 6-chloronicotinic acid, 6-chloronicotinaldehyde, and 6-hydroxynicotinic acid were determined by GC-MS analysis. Before complete mineralization, formic, acetic, oxalic, and glyoxylic acids were identified as end-products. The initial chlorine and organic nitrogen present in ICP were found to be converted to inorganic anions Cl(-), NO₃(-), and NH₄(+).

  17. Efficient removal of insecticide "imidacloprid" from water by electrochemical advanced oxidation processes.

    PubMed

    Turabik, Meral; Oturan, Nihal; Gözmen, Belgin; Oturan, Mehmet A

    2014-01-01

    The oxidative degradation of imidacloprid (ICP) has been carried out by electrochemical advanced oxidation processes (EAOPs), anodic oxidation, and electro-Fenton, in which hydroxyl radicals are generated electrocatalytically. Carbon-felt cathode and platinum or boron-doped diamond (BDD) anodes were used in electrolysis cell. To determine optimum operating conditions, the effects of applied current and catalyst concentration were investigated. The decay of ICP during the oxidative degradation was well fitted to pseudo-first-order reaction kinetics and absolute rate constant of the oxidation of ICP by hydroxyl radicals was found to be k abs(ICP) = 1.23 × 10(9) L mol(-1) s(-1). The results showed that both anodic oxidation and electro-Fenton process with BDD anode exhibited high mineralization efficiency reaching 91 and 94% total organic carbon (TOC) removal at 2 h, respectively. For Pt-EF process, mineralization efficiency was also obtained as 71%. The degradation products of ICP were identified and a plausible general oxidation mechanism was proposed. Some of the main reaction intermediates such as 6-chloronicotinic acid, 6-chloronicotinaldehyde, and 6-hydroxynicotinic acid were determined by GC-MS analysis. Before complete mineralization, formic, acetic, oxalic, and glyoxylic acids were identified as end-products. The initial chlorine and organic nitrogen present in ICP were found to be converted to inorganic anions Cl(-), NO₃(-), and NH₄(+). PMID:24671401

  18. Advanced Multi-Component Defect Cluster Oxide Doped Zirconia-Yttria Thermal Barrier Coatings

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Miller, Robert A.

    1990-01-01

    The advantages of using ceramic thermal barrier coatings in gas turbine engine hot sections include increased fuel efficiency and improved engine reliability. However, current thermal barrier coatings will not have the low thermal conductivity and necessary sintering resistance under higher operating temperatures and thermal gradients required by future advanced ultra-efficient and low-emission aircraft engines. In this paper, a novel oxide defect cluster design approach is described for achieving low thermal conductivity and excellent thermal stability of the thermal barrier coating systems. This approach utilizes multi-component rare earth and other metal cluster oxide dopants that are incorporated in the zirconia-yttria based systems, thus significantly reducing coating thermal conductivity and sintering resistance by effectively promoting the formation of thermodynamically stable, essentially immobile defect clusters and/or nanoscale phases. The performance of selected plasma-sprayed cluster oxide thermal barrier coating systems has been evaluated. The advanced multi-component thermal barrier coating systems were found to have significantly lower initial and long-term thermal conductivities, and better high temperature stability. The effect of oxide cluster dopants on coating thermal conductivity, sintering resistance, oxide grain growth behavior and durability will be discussed.

  19. Advanced Multi-Component Defect Cluster Oxide Doped Zirconia-Yttria Thermal Barrier Coatings

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Miller, Robert A.

    2003-01-01

    The advantages of using ceramic thermal barrier coatings in gas turbine engine hot sections include increased fuel efficiency and improved engine reliability. However, current thermal barrier coatings will not have the low thermal conductivity and necessary sintering resistance under higher operating temperatures and thermal gradients required by future advanced ultra efficient and low emission aircraft engines. In this paper, a novel oxide defect cluster design approach is described for achieving low thermal conductivity and excellent thermal stability of the thermal barrier coating systems. This approach utilizes multi-component rare earth and other metal cluster oxide dopants that are incorporated in the zirconia-yttna based systems, thus significantly reducing coating thermal conductivity and sintering resistance by effectively promoting the formation of thermodynamically stable, essentially immobile defect clusters and/or nanoscale phases. The performance of selected plasma-sprayed cluster oxide thermal barrier coating systems has been evaluated. The advanced multi-component thermal barrier coating systems were found to have significantly lower initial and long-term thermal conductivities, and better high temperature stability. The effect of oxide cluster dopants on coating thermal conductivity, sintering resistance, oxide grain growth behavior and durability will be discussed.

  20. Method for removing oxide contamination from titanium diboride powder

    DOEpatents

    Brynestad, J.; Bamberger, C.E.

    A method for removing oxide contamination from titanium diboride powder involves the direct chemical treatment of TiB/sub 2/ powders with a gaseous boron halide, such as BCl/sub 3/, at temperatures in the range of 500 to 800/sup 0/C. The BCl/sub 3/ reacts with the oxides to form volatile species which are removed by the BCl/sub 3/ exit stream.

  1. Method for removing oxide contamination from titanium diboride powder

    DOEpatents

    Brynestad, Jorulf; Bamberger, Carlos E.

    1984-01-01

    A method for removing oxide contamination from titanium diboride powder involves the direct chemical treatment of TiB.sub.2 powders with a gaseous boron halide, such as BCl.sub.3, at temperatures in the range of 500.degree.-800.degree. C. The BCl.sub.3 reacts with the oxides to form volatile species which are removed by the BCl.sub.3 exit stream.

  2. Novel glass inspection method for advanced photomask blanks

    NASA Astrophysics Data System (ADS)

    Tanabe, Masaru; Kikuchi, Toshiharu; Hashimoto, Masahiro; Ohkubo, Yasushi

    2007-05-01

    Recently, extremely-high-quality-quartz substrates have been demanded for advancing ArF-lithography. HOYA has developed a novel inspection method for interior defects as well as surface defects. The total internal reflection of the substrate is employed to produce an ideal dark field illumination. The novel inspection method can detect a "nano-pit" of 12nm-EDS, the Equivalent of the Diameter of a Sphere (EDS). It will meet the sensitivity for 32nm node and beyond. Moreover, a type of unique defect is detected, which induces Serious Transmittance Error for Arf-LiTHography. We call it the "STEALTH" defect. It is a killer defect in wafer printing; but it cannot be detected with any conventional inspection in the mask-making process so far. In this paper, the performance of the novel inspection method for quartz substrates and the investigation of "STEALTH" are reported.

  3. Identification of transformation products during advanced oxidation of diatrizoate: Effect of water matrix and oxidation process.

    PubMed

    Azerrad, Sara P; Lütke Eversloh, Christian; Gilboa, Maayan; Schulz, Manoj; Ternes, Thomas; Dosoretz, Carlos G

    2016-10-15

    Removal of micropollutants from reverse osmosis (RO) brines of wastewater desalination by oxidation processes is influenced by the scavenging capacity of brines components, resulting in the accumulation of transformation products (TPs) rather than complete mineralization. In this work the iodinated contrast media diatrizoate (DTZ) was used as model compound due to its relative resistance to oxidation. Identification of TPs was performed in ultrapure water (UPW) and RO brines applying nonthermal plasma (NTP) and UVA-TiO2 as oxidation techniques. The influence of main RO brines components in the formation and accumulation of TPs, such as chloride, bicarbonate alkalinity and humic acid, was also studied during UVA-TiO2. DTZ oxidation pattern in UPW resulted similar in both UVA-TiO2 and NTP achieving 66 and 61% transformation, respectively. However, DTZ transformation in RO brines was markedly lower in UVA-TiO2 (9%) than in NTP (27%). These differences can be attributed to the synergic effect of RO brines components during NTP. Moreover, reactive species other than hydroxyl radical contributed to DTZ transformation, i.e., direct photolysis in UVA-TiO2 and direct photolysis + O3 in NTP accounted for 16 and 23%, respectively. DTZ transformation led to iodide formation in both oxidation techniques but it further oxidized to iodate by ozone in NTP. In total 14 transformation products were identified in UPW of which 3 were present only in UVA-TiO2 and 2 were present exclusively in NTP; 5 of the 14 TPs were absent in RO brines. Five of them were new and were denoted as TP-474A/B, TP-522, TP-586, TP-602, TP-628. TP-522 (mono-chlorinated) was elucidated only in presence of high chloride titer-synthetic water matrix in NTP, most probably formed by active chlorine species generated in situ. TPs accumulation in RO brines was markedly different in comparison to UPW. This denotes the influence of RO brines components in the formation of reactive species that could further attack

  4. Identification of transformation products during advanced oxidation of diatrizoate: Effect of water matrix and oxidation process.

    PubMed

    Azerrad, Sara P; Lütke Eversloh, Christian; Gilboa, Maayan; Schulz, Manoj; Ternes, Thomas; Dosoretz, Carlos G

    2016-10-15

    Removal of micropollutants from reverse osmosis (RO) brines of wastewater desalination by oxidation processes is influenced by the scavenging capacity of brines components, resulting in the accumulation of transformation products (TPs) rather than complete mineralization. In this work the iodinated contrast media diatrizoate (DTZ) was used as model compound due to its relative resistance to oxidation. Identification of TPs was performed in ultrapure water (UPW) and RO brines applying nonthermal plasma (NTP) and UVA-TiO2 as oxidation techniques. The influence of main RO brines components in the formation and accumulation of TPs, such as chloride, bicarbonate alkalinity and humic acid, was also studied during UVA-TiO2. DTZ oxidation pattern in UPW resulted similar in both UVA-TiO2 and NTP achieving 66 and 61% transformation, respectively. However, DTZ transformation in RO brines was markedly lower in UVA-TiO2 (9%) than in NTP (27%). These differences can be attributed to the synergic effect of RO brines components during NTP. Moreover, reactive species other than hydroxyl radical contributed to DTZ transformation, i.e., direct photolysis in UVA-TiO2 and direct photolysis + O3 in NTP accounted for 16 and 23%, respectively. DTZ transformation led to iodide formation in both oxidation techniques but it further oxidized to iodate by ozone in NTP. In total 14 transformation products were identified in UPW of which 3 were present only in UVA-TiO2 and 2 were present exclusively in NTP; 5 of the 14 TPs were absent in RO brines. Five of them were new and were denoted as TP-474A/B, TP-522, TP-586, TP-602, TP-628. TP-522 (mono-chlorinated) was elucidated only in presence of high chloride titer-synthetic water matrix in NTP, most probably formed by active chlorine species generated in situ. TPs accumulation in RO brines was markedly different in comparison to UPW. This denotes the influence of RO brines components in the formation of reactive species that could further attack

  5. High temperature methods for forming oxidizer fuel

    SciTech Connect

    Bravo, Jose Luis

    2011-01-11

    A method of treating a formation fluid includes providing formation fluid from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes carbon dioxide, hydrogen sulfide, hydrocarbons, hydrogen or mixtures thereof. Molecular oxygen is separated from air to form a molecular oxygen stream comprising molecular oxygen. The first gas stream is combined with the molecular oxygen stream to form a combined stream comprising molecular oxygen and the first gas stream. The combined stream is provided to one or more downhole burners.

  6. Salt-stone Oxidation Study: Leaching Method - 13092

    SciTech Connect

    Langton, C.A.; Stefanko, D.B.; Burns, H.H.

    2013-07-01

    Cementitious waste forms can be designed to chemically stabilize selected contaminants, such as Tc{sup +7} and Cr{sup +6}, by chemically reduction to lower valance states, Tc{sup +4} and Cr{sup +3}, respectively, and precipitation of these species in alkaline media as low solubility solid phases. Data for oxidation of this type of cementitious waste form cured under field conditions as a function of time is required for predicting the performance of the waste form and disposal facility. The rate of oxidation (oxidation front advancement) is an important parameter for predicting performance because the solubilities of some radionuclide contaminants, e.g., technetium, are a function of the oxidation state. A non-radioactive experiment was designed for quantifying the oxidation front advancement using chromium, as an approximate redox-sensitive surrogate (Cr{sup +6} / Cr{sup +3}) for technetium (Tc{sup +7} / Tc{sup +4}). Nonradioactive cementitious waste forms were prepared in the laboratory and cured under both laboratory and 'field conditions'. Laboratory conditions were ambient temperature and sealed sample containers. Field conditions were approximated by curing samples in open containers which were placed inside a plastic container stored outdoors at SRS. The container had a lid and was instrumented with temperature and humidity probes. Sub-samples as thin as 0.2 mm were taken as a function of distance from the exposed surface of the as-cast sample. The sub-samples were leached and the leachates were analyzed for chromium, nitrate, nitrite and sodium. Nitrate, nitrite, and sodium concentrations were used to provide baseline data because these species are not chemically retained in the waste form matrix to any significant extent and are not redox sensitive. 'Effective' oxidation fronts for Cr were measured for samples containing 1000, 500 and 20 mg/kg Cr added as soluble sodium chromate, Na{sub 2}CrO{sub 4}. For a sample cured for 129 days under field conditions

  7. Methods of making metal oxide nanostructures and methods of controlling morphology of same

    DOEpatents

    Wong, Stanislaus S; Hongjun, Zhou

    2012-11-27

    The present invention includes a method of producing a crystalline metal oxide nanostructure. The method comprises providing a metal salt solution and providing a basic solution; placing a porous membrane between the metal salt solution and the basic solution, wherein metal cations of the metal salt solution and hydroxide ions of the basic solution react, thereby producing a crystalline metal oxide nanostructure.

  8. Method of removing oxides of sulfur and oxides of nitrogen from exhaust gases

    DOEpatents

    Walker, Richard J.

    1986-01-01

    A continuous method is presented for removing both oxides of sulfur and oxides of nitrogen from combustion or exhaust gases with the regeneration of the absorbent. Exhaust gas is cleaned of particulates and HCl by a water scrub prior to contact with a liquid absorbent that includes an aqueous solution of bisulfite and sulfite ions along with a metal chelate, such as, an iron or zinc aminopolycarboxylic acid. Following contact with the combustion gases the spent absorbent is subjected to electrodialysis to transfer bisulfite ions into a sulfuric acid solution while splitting water with hydroxide and hydrogen ion migration to equalize electrical charge. The electrodialysis stack includes alternate layers of anion selective and bipolar membranes. Oxides of nitrogen are removed from the liquid absorbent by air stripping at an elevated temperature and the regenerated liquid absorbent is returned to contact with exhaust gases for removal of sulfur oxides and nitrogen oxides.

  9. Microwave enhanced advanced oxidation process for treating dairy manure at low pH.

    PubMed

    Lo, Kwang V; Chan, Winnie W I; Yawson, Selina K; Liao, Ping H

    2012-01-01

    This study investigated the treatment of dairy manure using the microwave enhanced advanced oxidation process (MW-AOP) at pH 2. An experimental design was developed based on a statistical program using response surface methodology to explore the effects of temperature, hydrogen peroxide dosage and heating time on sugar production, nutrient release and solids destruction. Temperature, hydrogen peroxide dosage and acid concentration were key factors affecting reducing sugar production. The highest reducing sugar yield of 7.4% was obtained at 160°C, 0 mL, 15 min heating time, and no H(2)O(2) addition. Temperature was a dominant factor for an increase of soluble chemical oxygen demand (SCOD) in the treated dairy manure. The important factors for volatile fatty acids (VFA) production were microwave temperature and hydrogen peroxide dosage. Temperature was the most important parameter, and heating time, to a lesser extent affecting orthophosphate release. Heating time, hydrogen peroxide dosage and temperature were significant factors for ammonia release. There was a maximum of 96% and 196% increase in orthophosphate and ammonia concentration, respectively at 160°C, 0.5 mL H(2)O(2) and 15 min heating time. The MW-AOP is an effective method in dairy manure treatment for sugar production, nutrient solubilisation, and solids disintegration.

  10. Response surface methodology for ozonation of trifluralin using advanced oxidation processes in an airlift photoreactor

    NASA Astrophysics Data System (ADS)

    Behin, J.; Farhadian, N.

    2016-06-01

    Degradation of trifluralin, as a wide used pesticide, was investigated by advance oxidation process comprising O3/UV/H2O2 in a concentric tube airlift photoreactor. Main and interactive effects of three independent factors including pH (5-9), superficial gas velocity (0.05-0.15 cm/s) and time (20-60 min) on the removal efficiency were assessed using central composite face-centered design and response surface method (RSM). The RSM allows to solve multivariable equations and to estimate simultaneously the relative importance of several contributing parameters even in the presence of complex interaction. Airlift photoreactor imposed a synergistic effect combining good mixing intensity merit with high ozone transfer rate. Mixing in the airlift photoreactor enhanced the UV light usage efficiency and its availability. Complete degradation of trifluralin was achieved under optimum conditions of pH 9 and superficial gas velocity 0.15 cm/s after 60 min of reaction time. Under these conditions, degradation of trifluralin was performed in a bubble column photoreactor of similar volume and a lower efficiency was observed.

  11. Simulation for Supporting Scale-Up of a Fluidized Bed Reactor for Advanced Water Oxidation

    PubMed Central

    Abdul Raman, Abdul Aziz; Daud, Wan Mohd Ashri Wan

    2014-01-01

    Simulation of fluidized bed reactor (FBR) was accomplished for treating wastewater using Fenton reaction, which is an advanced oxidation process (AOP). The simulation was performed to determine characteristics of FBR performance, concentration profile of the contaminants, and various prominent hydrodynamic properties (e.g., Reynolds number, velocity, and pressure) in the reactor. Simulation was implemented for 2.8 L working volume using hydrodynamic correlations, continuous equation, and simplified kinetic information for phenols degradation as a model. The simulation shows that, by using Fe3+ and Fe2+ mixtures as catalyst, TOC degradation up to 45% was achieved for contaminant range of 40–90 mg/L within 60 min. The concentration profiles and hydrodynamic characteristics were also generated. A subsequent scale-up study was also conducted using similitude method. The analysis shows that up to 10 L working volume, the models developed are applicable. The study proves that, using appropriate modeling and simulation, data can be predicted for designing and operating FBR for wastewater treatment. PMID:25309949

  12. Review of photochemical reaction constants of organic micropollutants required for UV advanced oxidation processes in water.

    PubMed

    Wols, B A; Hofman-Caris, C H M

    2012-06-01

    Emerging organic contaminants (pharmaceutical compounds, personal care products, pesticides, hormones, surfactants, fire retardants, fuel additives etc.) are increasingly found in water sources and therefore need to be controlled by water treatment technology. UV advanced oxidation technologies are often used as an effective barrier against organic contaminants. The combined operation of direct photolysis and reaction with hydroxyl radicals ensures good results for a wide range of contaminants. In this review, an overview is provided of the photochemical reaction parameters (quantum yield, molar absorption, OH radical reaction rate constant) of more than 100 organic micropollutants. These parameters allow for a prediction of organic contaminant removal by UV advanced oxidation systems. An example of contaminant degradation is elaborated for a simplified UV/H(2)O(2) system. PMID:22483836

  13. Review of photochemical reaction constants of organic micropollutants required for UV advanced oxidation processes in water.

    PubMed

    Wols, B A; Hofman-Caris, C H M

    2012-06-01

    Emerging organic contaminants (pharmaceutical compounds, personal care products, pesticides, hormones, surfactants, fire retardants, fuel additives etc.) are increasingly found in water sources and therefore need to be controlled by water treatment technology. UV advanced oxidation technologies are often used as an effective barrier against organic contaminants. The combined operation of direct photolysis and reaction with hydroxyl radicals ensures good results for a wide range of contaminants. In this review, an overview is provided of the photochemical reaction parameters (quantum yield, molar absorption, OH radical reaction rate constant) of more than 100 organic micropollutants. These parameters allow for a prediction of organic contaminant removal by UV advanced oxidation systems. An example of contaminant degradation is elaborated for a simplified UV/H(2)O(2) system.

  14. Recent Advances in the Synthesis and Stabilization of Nickel and Nickel Oxide Nanoparticles: A Green Adeptness

    PubMed Central

    Rani, Aneela

    2016-01-01

    Green protocols for the synthesis of nanoparticles have been attracting a lot of attention because they are eco-friendly, rapid, and cost-effective. Nickel and nickel oxide nanoparticles have been synthesized by green routes and characterized for impact of green chemistry on the properties and biological effects of nanoparticles in the last five years. Green synthesis, properties, and applications of nickel and nickel oxide nanoparticles have been reported in the literature. This review summarizes the synthesis of nickel and nickel oxide nanoparticles using different biological systems. This review also provides comparative overview of influence of chemical synthesis and green synthesis on structural properties of nickel and nickel oxide nanoparticles and their biological behavior. It concludes that green methods for synthesis of nickel and nickel oxide nanoparticles are better than chemical synthetic methods. PMID:27413375

  15. Recent Advances in the Synthesis and Stabilization of Nickel and Nickel Oxide Nanoparticles: A Green Adeptness.

    PubMed

    Imran Din, Muhammad; Rani, Aneela

    2016-01-01

    Green protocols for the synthesis of nanoparticles have been attracting a lot of attention because they are eco-friendly, rapid, and cost-effective. Nickel and nickel oxide nanoparticles have been synthesized by green routes and characterized for impact of green chemistry on the properties and biological effects of nanoparticles in the last five years. Green synthesis, properties, and applications of nickel and nickel oxide nanoparticles have been reported in the literature. This review summarizes the synthesis of nickel and nickel oxide nanoparticles using different biological systems. This review also provides comparative overview of influence of chemical synthesis and green synthesis on structural properties of nickel and nickel oxide nanoparticles and their biological behavior. It concludes that green methods for synthesis of nickel and nickel oxide nanoparticles are better than chemical synthetic methods. PMID:27413375

  16. Advanced Catalysts for the Ambient Temperature Oxidation of Carbon Monoxide and Formaldehyde

    NASA Technical Reports Server (NTRS)

    Nalette, Tim; Eldridge, Christopher; Yu, Ping; Alpetkin, Gokhan; Graf, John

    2010-01-01

    The primary applications for ambient temperature carbon monoxide (CO) oxidation catalysts include emergency breathing masks and confined volume life support systems, such as those employed on the Shuttle. While Hopcalite is typically used in emergency breathing masks for terrestrial applications, in the 1970s, NASA selected a 2% platinum (Pt) on carbon for use on the Shuttle since it is more active and also more tolerant to water vapor. In the last 10-15 years there have been significant advances in ambient temperature CO oxidation catalysts. Langley Research Center developed a monolithic catalyst for ambient temperature CO oxidation operating under stoichiometric conditions for closed loop carbon dioxide (CO2) laser applications which is also advertised as having the potential to oxidize formaldehyde (HCHO) at ambient temperatures. In the last decade it has been discovered that appropriate sized nano-particles of gold are highly active for CO oxidation, even at sub-ambient temperatures, and as a result there has been a wealth of data reported in the literature relating to ambient/low temperature CO oxidation. In the shorter term missions where CO concentrations are typically controlled via ambient temperature oxidation catalysts, formaldehyde is also a contaminant of concern, and requires specially treated carbons such as Calgon Formasorb as untreated activated carbon has effectively no HCHO capacity. This paper examines the activity of some of the newer ambient temperature CO and formaldehyde (HCHO) oxidation catalysts, and measures the performance of the catalysts relative to the NASA baseline Ambient Temperature Catalytic Oxidizer (ATCO) catalyst at conditions of interest for closed loop trace contaminant control systems.

  17. Development of nanomaterial-enabled advanced oxidation techniques for treatment of organic micropollutants

    NASA Astrophysics Data System (ADS)

    Oulton, Rebekah Lynn

    Increasing demand for limited fresh water resources necessitates that alternative water sources be developed. Nonpotable reuse of treated wastewater represents one such alternative. However, the ubiquitous presence of organic micropollutants such as pharmaceuticals and personal care products (PPCPs) in wastewater effluents limits use of this resource. Numerous investigations have examined PPCP fate during wastewater treatment, focusing on their removal during conventional and advanced treatment processes. Analysis of influent and effluent data from published studies reveals that at best 1-log10 concentration unit of PPCP removal can generally be achieved with conventional treatment. In contrast, plants employing advanced treatment methods, particularly ozonation and/or membranes, remove most PPCPs often to levels below analytical detection limits. However, membrane treatment is cost prohibitive for many facilities, and ozone treatment can be very selective. Ozone-recalcitrant compounds require the use of Advanced Oxidation Processes (AOPs), which utilize highly reactive hydroxyl radicals (*OH) to target resistant pollutants. Due to cost and energy use concerns associated with current AOPs, alternatives such as catalytic ozonation are under investigation. Catalytic ozonation uses substrates such as activated carbon to promote *OH formation during ozonation. Here, we show that multi-walled carbon nanotubes (MWCNTs) represent another viable substrate, promoting *OH formation during ozonation to levels exceeding activated carbon and equivalent to conventional ozone-based AOPs. Via a series of batch reactions, we observ a strong correlation between *OH formation and MWCNT surface oxygen concentrations. Results suggest that deprotonated carboxyl groups on the CNT surface are integral to their reactivity toward ozone and corresponding *OH formation. From a practical standpoint, we show that industrial grade MWCNTs exhibit similar *OH production as their research

  18. Voltage oxide removal for plating: A new method of electroplating oxide coated metals in situ

    SciTech Connect

    Gutfeld, R. J. von; West, A. C.

    2007-03-15

    A novel in situ method for electroplating oxide coated metals is described. Termed VORP, for voltage oxide removal for plating, the process utilizes a voltage pulse {approx}20-200 V, {approx}2 ms in duration, applied between working and counterelectrodes while both are immersed in a copper electrolyte. The pulse is almost immediately followed by galvanostatic plate-up. Adherent copper deposits up to {approx}4 {mu}m in height on stainless steel 316 coupons have been obtained. Temperature testing up to 260 deg. C in air does not affect the copper adhesion. A preliminary model for oxide removal is proposed utilizing concepts of dielectric breakdown.

  19. Methods and systems for advanced spaceport information management

    NASA Technical Reports Server (NTRS)

    Fussell, Ronald M. (Inventor); Ely, Donald W. (Inventor); Meier, Gary M. (Inventor); Halpin, Paul C. (Inventor); Meade, Phillip T. (Inventor); Jacobson, Craig A. (Inventor); Blackwell-Thompson, Charlie (Inventor)

    2007-01-01

    Advanced spaceport information management methods and systems are disclosed. In one embodiment, a method includes coupling a test system to the payload and transmitting one or more test signals that emulate an anticipated condition from the test system to the payload. One or more responsive signals are received from the payload into the test system and are analyzed to determine whether one or more of the responsive signals comprises an anomalous signal. At least one of the steps of transmitting, receiving, analyzing and determining includes transmitting at least one of the test signals and the responsive signals via a communications link from a payload processing facility to a remotely located facility. In one particular embodiment, the communications link is an Internet link from a payload processing facility to a remotely located facility (e.g. a launch facility, university, etc.).

  20. Methods and Systems for Advanced Spaceport Information Management

    NASA Technical Reports Server (NTRS)

    Fussell, Ronald M. (Inventor); Ely, Donald W. (Inventor); Meier, Gary M. (Inventor); Halpin, Paul C. (Inventor); Meade, Phillip T. (Inventor); Jacobson, Craig A. (Inventor); Blackwell-Thompson, Charlie (Inventor)

    2007-01-01

    Advanced spaceport information management methods and systems are disclosed. In one embodiment, a method includes coupling a test system to the payload and transmitting one or more test signals that emulate an anticipated condition from the test system to the payload. One or more responsive signals are received from the payload into the test system and are analyzed to determine whether one or more of the responsive signals comprises an anomalous signal. At least one of the steps of transmitting, receiving, analyzing and determining includes transmitting at least one of the test signals and the responsive signals via a communications link from a payload processing facility to a remotely located facility. In one particular embodiment, the communications link is an Internet link from a payload processing facility to a remotely located facility (e.g. a launch facility, university, etc.).

  1. Methods to monitor classical protein-tyrosine phosphatase oxidation

    PubMed Central

    Karisch, Robert; Neel, Benjamin G.

    2012-01-01

    SUMMARY Reactive oxygen species (ROS), particularly H2O2, act as intracellular second messengers in many signaling pathways. Protein-tyrosine phosphatases (PTPs) are now believed to be important targets of ROS. PTPs contain a conserved catalytic cysteine with an unusually low pKa. This property allows PTPs to execute nucleophilic attack on substrate phosphotyrosyl residues, but also renders them highly susceptible to oxidation. Reversible oxidation, which inactivates PTPs, is emerging as an important cellular regulatory mechanism and might contribute to human diseases, including cancer. Given their potential toxicity, it seems likely that ROS generation is highly controlled within cells to restrict oxidation to those PTPs that must be inactivated for signaling to proceed. Thus, identifying ROS-inactivated PTPs could be tantamount to finding the PTP(s) that critically regulate a specific signaling pathway. This article provides an overview of the methods currently available to identify and quantify PTP oxidation and outlines future challenges in redox signaling. PMID:22577968

  2. Improving the Oxidation Resistance in Advanced Single Crystal Nickel-Based Superalloys for Turbine Applications

    SciTech Connect

    Alexander, K.B.; Kenik, E.A.; Miller, M.K.; Lin, L.S.; Cetel, A.D.

    1999-07-01

    The focus of this project was the examination of the role of yttrium and other alloying elements on the microstructure and oxidation performance of improved single crystal nickel-based superalloys for advanced turbine applications. The microstructure and microchemistry of both base and modified alloys and their surface oxides have been measured with state-of-the-art microanalytical techniques (atom probe field ion microscopy) and then correlated with identifying the partitioning behavior of the elemental additions in these superalloys before and after burner rig and engine-test oxidation performance. The overall technical goals included; (1) identifying the partitioning behavior of the elemental additions in these superalloys before and after burner rig and engine tests and the effect on the misfit energy between the phases in the alloys; (2) examining the oxidation performance of these newly-developed alloys; (3) identifying the influence of pre-oxidation processing on the subsequent oxidation performance; and (4) relating the microstructural and microchemical observations to the observed performance of these superalloys. The comparison of the base and modified alloys will produce a better understanding of the interaction between chemistry, structure, and performance in superalloys. In addition, it will lead to optimized alloys with improved performance including enhanced durability in the operating environments at the elevated temperature required to improve energy efficiency. The availability of alloys capable of higher temperature operation will minimize the need for expensive coatings in extreme temperature applications.

  3. Advanced Recycling Core Accommodating Oxide Fuel and Metal Fuel for Closed Fuel Cycle

    NASA Astrophysics Data System (ADS)

    Ikeda, Kazumi; Maddox, James W.; Nakazato, Wataru; Kunishima, Shigeru

    This report presents a unique TRU burning core capable of accommodating oxide fuel and metal fuel and easy to change oxide core to metal core conforming to the design requirements. For the homogeneous oxide fueled core containing transuranics (TRU) fuel with 12% of the moderator pins, the results of calculation show the TRU conversion ratio (ratio of loss of TRU to loss of heavy metal) of 0.33 and the TRU burning capability (ratio of loss of TRU per electric generation) of 67 kg/TWeh. On the other hand, the calculations replacing from oxide fuel assemblies to metal fuel assemblies have indicated the TRU transmutation capability of 69 kg/TWeh with the TRU conversion ratio of 0.30. As the result of simulation calculations, three ordinary fuel exchanges transform the oxide equilibrium core to the full metal core by way of transitional cores, where the maximum linear heat rates are still equal to the metal equilibrium core or less. With this, the presented core concept is concluded that a full oxide core, a full metal core, mixed fueled cores can be materialized in the presented first unit of Advanced Recycling Reactor (ARR1).

  4. Determination of nitrous oxide concentrations by spectroscopic method

    NASA Astrophysics Data System (ADS)

    Mirzoeva, Larissa A.; Kiseleva, Margarete S.; Sinelnikova, Galina E.

    1990-08-01

    In the proposed paper an empirical method has been developed for determination of nitrous oxide concentration using the absorption band 2'), in proximity of), 3.87J4m, free from overlapping with absorption bands from other atmospheric gases. The transmission spectra of the atmospheric air are recorded with unresolved rotation-vibration structure. The method is inexpensive, simple and efficient It may be used for determination of enviromental pollution in homogeneous media (laboratory or production plant conditions, ground layer of atmosphere) and of unhomogeneous composistion mixtures when studying the contents of nitrous oxide along slope paths in troposphere and stratosphere.

  5. Regeneration of siloxane-exhausted activated carbon by advanced oxidation processes.

    PubMed

    Cabrera-Codony, Alba; Gonzalez-Olmos, Rafael; Martín, Maria J

    2015-03-21

    In the context of the biogas upgrading, siloxane exhausted activated carbons need to be regenerated in order to avoid them becoming a residue. In this work, two commercial activate carbons which were proved to be efficient in the removal of octamethylcyclotetrasiloxane (D4) from biogas, have been regenerated through advanced oxidation processes using both O3 and H2O2. After the treatment with O3, the activated carbon recovered up to 40% of the original adsorption capacity while by the oxidation with H2O2 the regeneration efficiency achieved was up to 45%. In order to enhance the H2O2 oxidation, activated carbon was amended with iron. In this case, the regeneration efficiency increased up to 92%.

  6. Method to fabricate high performance tubular solid oxide fuel cells

    SciTech Connect

    Chen, Fanglin; Yang, Chenghao; Jin, Chao

    2013-06-18

    In accordance with the present disclosure, a method for fabricating a solid oxide fuel cell is described. The method includes forming an asymmetric porous ceramic tube by using a phase inversion process. The method further includes forming an asymmetric porous ceramic layer on a surface of the asymmetric porous ceramic tube by using a phase inversion process. The tube is co-sintered to form a structure having a first porous layer, a second porous layer, and a dense layer positioned therebetween.

  7. Advanced Oxide Material Systems for 1650 C Thermal/Environmental Barrier Coating Applications

    NASA Technical Reports Server (NTRS)

    Zhu, Dong-Ming; Fox, Dennis S.; Bansal, Narottam P.; Miller, Robert A.

    2004-01-01

    Advanced thermal and environmental barrier coatings (TEBCs) are being developed for low-emission SiC/SiC ceramic matrix composite (CMC) combustor and vane applications to extend the CMC liner and vane temperature capability to 1650 C (3000 F) in oxidizing and water-vapor-containing combustion environments. The advanced 1650 C TEBC system is required to have a better high-temperature stability, lower thermal conductivity, and more resistance to sintering and thermal stress than current coating systems under engine high-heat-flux and severe thermal cycling conditions. In this report, the thermal conductivity and water vapor stability of selected candidate hafnia-, pyrochlore- and magnetoplumbite-based TEBC materials are evaluated. The effects of dopants on the materials properties are also discussed. The test results have been used to downselect the TEBC materials and help demonstrate the feasibility of advanced 1650 C coatings with long-term thermal cycling durability.

  8. Copper Oxide Nanomaterials Prepared by Solution Methods, Some Properties, and Potential Applications: A Brief Review

    PubMed Central

    Tran, Thi Ha; Nguyen, Viet Tuyen

    2014-01-01

    Cupric oxide (CuO), having a narrow bandgap of 1.2 eV and a variety of chemophysical properties, is recently attractive in many fields such as energy conversion, optoelectronic devices, and catalyst. Compared with bulk material, the advanced properties of CuO nanostructures have been demonstrated; however, the fact that these materials cannot yet be produced in large scale is an obstacle to realize the potential applications of this material. In this respect, chemical methods seem to be efficient synthesis processes which yield not only large quantities but also high quality and advanced material properties. In this paper, the effect of some general factors on the morphology and properties of CuO nanomaterials prepared by solution methods will be overviewed. In terms of advanced nanostructure synthesis, microwave method in which copper hydroxide nanostructures are produced in the precursor solution and sequentially transformed by microwave into CuO may be considered as a promising method to explore in the near future. This method produces not only large quantities of nanoproducts in a short reaction time of several minutes, but also high quality materials with advanced properties. A brief review on some unique properties and applications of CuO nanostructures will be also presented. PMID:27437488

  9. On-the-Fly Kinetic Monte Carlo Simulation of Aqueous Phase Advanced Oxidation Processes.

    PubMed

    Guo, Xin; Minakata, Daisuke; Crittenden, John

    2015-08-01

    We have developed an on-the-fly kinetic Monte Carlo (KMC) model to predict the degradation mechanisms and fates of intermediates and byproducts that are produced during aqueous-phase advanced oxidation processes (AOPs). The on-the-fly KMC model is composed of a reaction pathway generator, a reaction rate constant estimator, a mechanistic reduction module, and a KMC solver. The novelty of this work is that we develop the pathway as we march forward in time rather than developing the pathway before we use the KMC method to solve the equations. As a result, we have fewer reactions to consider, and we have greater computational efficiency. We have verified this on-the-fly KMC model for the degradation of polyacrylamide (PAM) using UV light and titanium dioxide (i.e., UV/TiO2). Using the on-the-fly KMC model, we were able to predict the time-dependent profiles of the average molecular weight for PAM. The model provided detailed and quantitative insights into the time evolution of the molecular weight distribution and reaction mechanism. We also verified our on-the-fly KMC model for the destruction of (1) acetone, (2) trichloroethylene (TCE), and (3) polyethylene glycol (PEG) for the ultraviolet light and hydrogen peroxide AOP. We demonstrated that the on-the-fly KMC model can achieve the same accuracy as the computer-based first-principles KMC (CF-KMC) model, which has already been validated in our earlier work. The on-the-fly KMC is particularly suitable for molecules with large molecular weights (e.g., polymers) because the degradation mechanisms for large molecules can result in hundreds of thousands to even millions of reactions. The ordinary differential equations (ODEs) that describe the degradation pathways cannot be solved using traditional numerical methods, but the KMC can solve these equations.

  10. Recent advances in computational structural reliability analysis methods

    NASA Technical Reports Server (NTRS)

    Thacker, Ben H.; Wu, Y.-T.; Millwater, Harry R.; Torng, Tony Y.; Riha, David S.

    1993-01-01

    The goal of structural reliability analysis is to determine the probability that the structure will adequately perform its intended function when operating under the given environmental conditions. Thus, the notion of reliability admits the possibility of failure. Given the fact that many different modes of failure are usually possible, achievement of this goal is a formidable task, especially for large, complex structural systems. The traditional (deterministic) design methodology attempts to assure reliability by the application of safety factors and conservative assumptions. However, the safety factor approach lacks a quantitative basis in that the level of reliability is never known and usually results in overly conservative designs because of compounding conservatisms. Furthermore, problem parameters that control the reliability are not identified, nor their importance evaluated. A summary of recent advances in computational structural reliability assessment is presented. A significant level of activity in the research and development community was seen recently, much of which was directed towards the prediction of failure probabilities for single mode failures. The focus is to present some early results and demonstrations of advanced reliability methods applied to structural system problems. This includes structures that can fail as a result of multiple component failures (e.g., a redundant truss), or structural components that may fail due to multiple interacting failure modes (e.g., excessive deflection, resonate vibration, or creep rupture). From these results, some observations and recommendations are made with regard to future research needs.

  11. Advanced superposition methods for high speed turbopump vibration analysis

    NASA Technical Reports Server (NTRS)

    Nielson, C. E.; Campany, A. D.

    1981-01-01

    The small, high pressure Mark 48 liquid hydrogen turbopump was analyzed and dynamically tested to determine the cause of high speed vibration at an operating speed of 92,400 rpm. This approaches the design point operating speed of 95,000 rpm. The initial dynamic analysis in the design stage and subsequent further analysis of the rotor only dynamics failed to predict the vibration characteristics found during testing. An advanced procedure for dynamics analysis was used in this investigation. The procedure involves developing accurate dynamic models of the rotor assembly and casing assembly by finite element analysis. The dynamically instrumented assemblies are independently rap tested to verify the analytical models. The verified models are then combined by modal superposition techniques to develop a completed turbopump model where dynamic characteristics are determined. The results of the dynamic testing and analysis obtained are presented and methods of moving the high speed vibration characteristics to speeds above the operating range are recommended. Recommendations for use of these advanced dynamic analysis procedures during initial design phases are given.

  12. Nondestructive characterization methods for monolithic solid oxide fuel cells

    SciTech Connect

    Ellingson, W.A.

    1993-01-01

    Monolithic solid oxide fuel cells (MSOFCS) represent a potential breakthrough in fuel cell technology, provided that reliable fabrication methods can be developed. Fabrication difficulties arise in several steps of the processing: First is the fabrication of uniform thin (305 {mu}m) single-layer and trilayer green tapes (the trilayer tapes of anode/electrolyte/cathode and anode/interconnect/cathode must have similar coefficients of thermal expansion to sinter uniformly and to have the necessary electrochemical properties); Second is the development of fuel and oxidant channels in which residual stresses are likely to develop in the tapes; Third is the fabrication of a ``complete`` cell for which the bond quality between layers and the quality of the trilayers must be established; and Last, attachment of fuel and oxidant manifolds and verification of seal integrity. Purpose of this report is to assess nondestructive characterization methods that could be developed for application to laboratory, prototype, and full-scale MSOFCs.

  13. Exploration of Advanced Probabilistic and Stochastic Design Methods

    NASA Technical Reports Server (NTRS)

    Mavris, Dimitri N.

    2003-01-01

    The primary objective of the three year research effort was to explore advanced, non-deterministic aerospace system design methods that may have relevance to designers and analysts. The research pursued emerging areas in design methodology and leverage current fundamental research in the area of design decision-making, probabilistic modeling, and optimization. The specific focus of the three year investigation was oriented toward methods to identify and analyze emerging aircraft technologies in a consistent and complete manner, and to explore means to make optimal decisions based on this knowledge in a probabilistic environment. The research efforts were classified into two main areas. First, Task A of the grant has had the objective of conducting research into the relative merits of possible approaches that account for both multiple criteria and uncertainty in design decision-making. In particular, in the final year of research, the focus was on the comparison and contrasting between three methods researched. Specifically, these three are the Joint Probabilistic Decision-Making (JPDM) technique, Physical Programming, and Dempster-Shafer (D-S) theory. The next element of the research, as contained in Task B, was focused upon exploration of the Technology Identification, Evaluation, and Selection (TIES) methodology developed at ASDL, especially with regards to identification of research needs in the baseline method through implementation exercises. The end result of Task B was the documentation of the evolution of the method with time and a technology transfer to the sponsor regarding the method, such that an initial capability for execution could be obtained by the sponsor. Specifically, the results of year 3 efforts were the creation of a detailed tutorial for implementing the TIES method. Within the tutorial package, templates and detailed examples were created for learning and understanding the details of each step. For both research tasks, sample files and

  14. Advance in methods studying the pharmacokinetics of polyphenols.

    PubMed

    Santos, Ana C; Costa, G; Veiga, F; Figueiredo, I V; Batista, M T; Ribeiro, António J

    2014-01-01

    Significant advances have been achieved during the past decade concerning the metabolism of polyphenol compounds in vitro, but scarce data has been presented about what really happens in vivo. Many studies on polyphenols to date have focused on the bioactivity of one specific molecule in aglycone form, often at supraphysiological doses, whereas foods contain complex, often poorly characterized mixtures with multiple additive or interfering activities. Whereas most studies up to the middle-late 1990s measured total aglycones in plasma and urine, after chemical or enzymatic deconjugation, or both, several recent works now report the polyphenol conjugate composition of plasma, urine, feces and/or tissues, after the administration of pure polyphenols or polyphenol-rich matrices. HPLC methods with electrochemical, mass spectrometric and fluorescence detection have adequate sensitivity. LC/UV-Vis methods have also been widely reported, but they are much less sensitive. Compared with electro-chemical and fluorescence detection, MS can quantify analytes without chromatographic separation, which leads to high throughput, presenting itself as the best choice to date. Regarding the experimental model to monitor the bioavailability of phenolic compounds, most published studies are based on human and animal models, with the majority using rodents, primates and recently the nematode Caenorhabditis elegans. This review focuses on the fundamentals of pharmacokinetic methods from the last 15 years and how the results are evaluated and validated. The types of analytical methods, animal models and biological matrices were used to better elucidate pharmacokinetics of polyphenols.

  15. Advanced numerical methods in mesh generation and mesh adaptation

    SciTech Connect

    Lipnikov, Konstantine; Danilov, A; Vassilevski, Y; Agonzal, A

    2010-01-01

    Numerical solution of partial differential equations requires appropriate meshes, efficient solvers and robust and reliable error estimates. Generation of high-quality meshes for complex engineering models is a non-trivial task. This task is made more difficult when the mesh has to be adapted to a problem solution. This article is focused on a synergistic approach to the mesh generation and mesh adaptation, where best properties of various mesh generation methods are combined to build efficiently simplicial meshes. First, the advancing front technique (AFT) is combined with the incremental Delaunay triangulation (DT) to build an initial mesh. Second, the metric-based mesh adaptation (MBA) method is employed to improve quality of the generated mesh and/or to adapt it to a problem solution. We demonstrate with numerical experiments that combination of all three methods is required for robust meshing of complex engineering models. The key to successful mesh generation is the high-quality of the triangles in the initial front. We use a black-box technique to improve surface meshes exported from an unattainable CAD system. The initial surface mesh is refined into a shape-regular triangulation which approximates the boundary with the same accuracy as the CAD mesh. The DT method adds robustness to the AFT. The resulting mesh is topologically correct but may contain a few slivers. The MBA uses seven local operations to modify the mesh topology. It improves significantly the mesh quality. The MBA method is also used to adapt the mesh to a problem solution to minimize computational resources required for solving the problem. The MBA has a solid theoretical background. In the first two experiments, we consider the convection-diffusion and elasticity problems. We demonstrate the optimal reduction rate of the discretization error on a sequence of adaptive strongly anisotropic meshes. The key element of the MBA method is construction of a tensor metric from hierarchical edge

  16. Recent Advances in Preparation, Structure, Properties and Applications of Graphite Oxide.

    PubMed

    Srivastava, Suneel Kumar; Pionteck, Jürgen

    2015-03-01

    Graphite oxide, also referred as graphitic oxide or graphitic acid, is an oxidized bulk product of graphite with a variable composition. However, it did not receive immense attention until it was identified as an important and easily obtainable precursor for the preparation of graphene. This inspired many researchers to explore facts related to graphite oxide in exploiting its fascinating features. The present article culminates up-dated review on different preparative methods, morphology and characterization of physical/chemical properties of graphite oxide by XRD, XPS, FTIR, Raman, NMR, UV-visible, and DRIFT analyses. Finally, recent developments on intercalation and applications of GO in multifaceted areas of catalysis, sensor, supercapacitors, water purification, hydrogen storage and magnetic shielding etc. has also been reviewed.

  17. Advanced Motion Compensation Methods for Intravital Optical Microscopy.

    PubMed

    Vinegoni, Claudio; Lee, Sungon; Feruglio, Paolo Fumene; Weissleder, Ralph

    2014-03-01

    Intravital microscopy has emerged in the recent decade as an indispensible imaging modality for the study of the micro-dynamics of biological processes in live animals. Technical advancements in imaging techniques and hardware components, combined with the development of novel targeted probes and new mice models, have enabled us to address long-standing questions in several biology areas such as oncology, cell biology, immunology and neuroscience. As the instrument resolution has increased, physiological motion activities have become a major obstacle that prevents imaging live animals at resolutions analogue to the ones obtained in vitro. Motion compensation techniques aim at reducing this gap and can effectively increase the in vivo resolution. This paper provides a technical review of some of the latest developments in motion compensation methods, providing organ specific solutions.

  18. Advanced Motion Compensation Methods for Intravital Optical Microscopy

    PubMed Central

    Vinegoni, Claudio; Lee, Sungon; Feruglio, Paolo Fumene; Weissleder, Ralph

    2013-01-01

    Intravital microscopy has emerged in the recent decade as an indispensible imaging modality for the study of the micro-dynamics of biological processes in live animals. Technical advancements in imaging techniques and hardware components, combined with the development of novel targeted probes and new mice models, have enabled us to address long-standing questions in several biology areas such as oncology, cell biology, immunology and neuroscience. As the instrument resolution has increased, physiological motion activities have become a major obstacle that prevents imaging live animals at resolutions analogue to the ones obtained in vitro. Motion compensation techniques aim at reducing this gap and can effectively increase the in vivo resolution. This paper provides a technical review of some of the latest developments in motion compensation methods, providing organ specific solutions. PMID:24273405

  19. Online monitoring of Escherichia coli and Bacillus thuringiensis spore inactivation after advanced oxidation treatment.

    PubMed

    Sherchan, Samendra P; Snyder, Shane A; Gerba, Charles P; Pepper, Ian L

    2014-01-01

    Various studies have shown that advanced oxidation processes (AOPs) such as UV light in combination with hydrogen peroxide is an efficient process for the removal of a large variety of emerging contaminants including microorganisms. The mechanism of destruction in the presence of hydrogen peroxide (H2O2) is the enhanced formation of hydroxyl (·OH) radicals, which have a high oxidation potential. The goal of this study was to utilize in-line advanced oxidation to inactivate microbes, and document the inactivation via an in-line, real-time sensor. Escherichia coli cells and Bacillus thuringiensis spores were exposed to UV/H2O2 treatment in DI water, and the online sensor BioSentry(®) was evaluated for its potential to monitor inactivation in real-time. B. thuringiensis was selected as a non-pathogenic surrogate for B. anthracis, the causative agent of anthrax and a proven biological weapon. UV radiation and UV/H2O2 exposure resulted in a >6 log10 reduction of the viable culturable counts of E. coli vegetative cells, and a 3 log10 reduction of B. thuringiensis spores. Scanning electron microscopy of the treated samples revealed severe damage on the surface of most E. coli cells, yet there was no significant change observed in the morphology of the B. thuringiensis spores. Following AOP exposure, the BioSentry sensor showed an increase in the categories of unknown, rod and spores counts, but overall, did not correspond well with viable count assays. Data from this study show that advanced oxidation processes effectively inactivate E. coli vegetative cells, but not B. thuringiensis spores, which were more resistant to AOP. Further, the BioSentry in-line sensor was not successful in documenting destruction of the microbial cells in real-time.

  20. Advanced electrochemical methods for characterizing the performance of organic coatings

    NASA Astrophysics Data System (ADS)

    Upadhyay, Vinod

    Advanced electrochemical techniques such as electrochemical impedance spectroscopy (EIS), electrochemical noise method (ENM) and coulometry as tools to study and extract information about the coating system is the focus of this thesis. This thesis explored three areas of research. In all the three research areas, advanced electrochemical techniques were used to extract information and understand the coating system. The first area was to use EIS and coulometric technique for extracting information using AC-DC-AC method. It was examined whether the total charge passing through the coating during the DC polarization step of AC-DC-AC determines coating failure. An almost constant total amount of charge transfer was required by the coating before it failed and was independent of the applied DC polarization. The second area focused in this thesis was to investigate if embedded sensors in coatings are sensitive enough to monitor changes in environmental conditions and to locate defects in coatings by electrochemical means. Influence of topcoat on embedded sensor performance was also studied. It was observed that the embedded sensors can distinguish varying environmental conditions and locate defects in coatings. Topcoat could influence measurements made using embedded sensors and the choice of topcoat could be very important in the successful use of embedded sensors. The third area of research of this thesis work was to examine systematically polymer-structure coating property relationships using electrochemical impedance spectroscopy. It was observed that the polymer modifications could alter the electrochemical properties of the coating films. Moreover, it was also observed that by cyclic wet-dry capacitance measurement using aqueous electrolyte and ionic liquid, ranking of the stability of organic polymer films could be performed.

  1. Advancing MODFLOW Applying the Derived Vector Space Method

    NASA Astrophysics Data System (ADS)

    Herrera, G. S.; Herrera, I.; Lemus-García, M.; Hernandez-Garcia, G. D.

    2015-12-01

    The most effective domain decomposition methods (DDM) are non-overlapping DDMs. Recently a new approach, the DVS-framework, based on an innovative discretization method that uses a non-overlapping system of nodes (the derived-nodes), was introduced and developed by I. Herrera et al. [1, 2]. Using the DVS-approach a group of four algorithms, referred to as the 'DVS-algorithms', which fulfill the DDM-paradigm (i.e. the solution of global problems is obtained by resolution of local problems exclusively) has been derived. Such procedures are applicable to any boundary-value problem, or system of such equations, for which a standard discretization method is available and then software with a high degree of parallelization can be constructed. In a parallel talk, in this AGU Fall Meeting, Ismael Herrera will introduce the general DVS methodology. The application of the DVS-algorithms has been demonstrated in the solution of several boundary values problems of interest in Geophysics. Numerical examples for a single-equation, for the cases of symmetric, non-symmetric and indefinite problems were demonstrated before [1,2]. For these problems DVS-algorithms exhibited significantly improved numerical performance with respect to standard versions of DDM algorithms. In view of these results our research group is in the process of applying the DVS method to a widely used simulator for the first time, here we present the advances of the application of this method for the parallelization of MODFLOW. Efficiency results for a group of tests will be presented. References [1] I. Herrera, L.M. de la Cruz and A. Rosas-Medina. Non overlapping discretization methods for partial differential equations, Numer Meth Part D E, (2013). [2] Herrera, I., & Contreras Iván "An Innovative Tool for Effectively Applying Highly Parallelized Software To Problems of Elasticity". Geofísica Internacional, 2015 (In press)

  2. New advanced surface modification technique: titanium oxide ceramic surface implants: long-term clinical results

    NASA Astrophysics Data System (ADS)

    Szabo, Gyorgy; Kovacs, Lajos; Barabas, Jozsef; Nemeth, Zsolt; Maironna, Carlo

    2001-11-01

    The purpose of this paper is to discuss the background to advanced surface modification technologies and to present a new technique, involving the formation of a titanium oxide ceramic coating, with relatively long-term results of its clinical utilization. Three general techniques are used to modify surfaces: the addition or removal of material and the change of material already present. Surface properties can also be changed without the addition or removal of material, through the laser or electron beam thermal treatment. The new technique outlined in this paper relates to the production of a corrosion-resistant 2000-2500 A thick, ceramic oxide layer with a coherent crystalline structure on the surface of titanium implants. The layer is grown electrochemically from the bulk of the metal and is modified by heat treatment. Such oxide ceramic-coated implants have a number of advantageous properties relative to implants covered with various other coatings: a higher external hardness, a greater force of adherence between the titanium and the oxide ceramic coating, a virtually perfect insulation between the organism and the metal (no possibility of metal allergy), etc. The coated implants were subjected to various physical, chemical, electronmicroscopic, etc. tests for a qualitative characterization. Finally, these implants (plates, screws for maxillofacial osteosynthesis and dental root implants) were applied in surgical practice for a period of 10 years. Tests and the experience acquired demonstrated the good properties of the titanium oxide ceramic-coated implants.

  3. Enhancing hydrophilicity and water permeability of PET track-etched membranes by advanced oxidation process

    NASA Astrophysics Data System (ADS)

    Korolkov, Ilya V.; Mashentseva, Anastassiya A.; Güven, Olgun; Zdorovets, Maxim V.; Taltenov, Abzal A.

    2015-12-01

    In this study we present results on the application of advanced oxidation systems for effective and non-toxic oxidation of poly(ethylene terephthalate) track-etched membranes (PET TeMs) to improve their wettability and water transport properties. Two oxidizing systems: H2O2 under UV irradiation (H2O2/UV) and Fenton system under visible light (Fenton/H2O2/Vis) were compared. The surface of functionalized PET TeMs was characterized by using colorimetric assay, contact angle measurements and X-ray photoelectron spectroscopy (XPS). Results clearly showed that water permeability of PET TeMs treated with H2O2/UV was improved by 28 ± 5% compared with etched-only membrane, the same parameter was found to increase by 13 ± 4% in the case of Fenton/H2O2/Vis treatment. The proposed oxidation technique is very simple, environment friendly and not requiring special equipment or expensive chemicals. The surface hydrophilicity of the membranes stored for 360 days in air between paper sheets was analyzed by contact angle test, colorimetric assay to measure concentration of carboxylic groups on the surface with toluidine blue and XPS analysis. The hydrophilic properties of oxidized PET TeMs were found to be stable for a long period of time.

  4. Advanced functional oxide thin films grown by pulsed-laser deposition

    NASA Astrophysics Data System (ADS)

    Millon, E.

    2013-08-01

    Pulsed-laser deposition is now a largely used growth method to prepare functional and multifunctional oxide films for application in microelectronics, spintronics, optics, materials for energy… The functional properties of such oxide films are strongly depending on the crystalline structure, and on the chemical composition through the local environment of cationic species surrounded by oxygen. While large oxygen deficiency cannot be obtained by classical growth method or in bulk state, oxide films with a high content of oxygen vacancies may be obtained by PLD. For oxide systems presenting possible stable sub-oxides, the formation of oxygen vacancies is linked to a decrease of the cationic valence state. A complete reduction can be observed leading to particular electronic properties: the case of TiOx (1.5 < x < 2) will be therefore presented and discussed. When no thermodynamically stable sub-oxides can be involved, the large oxygen deficiency may lead to the formation of nanocomposite films constituted by a metallic phase embedded in a stoichiometric oxide matrix. This phase separation induced by the control of oxygen pressure during the growth is in particular evidenced on Ga2Ox (2.1 < x < 3) films and their related physical (electrical and optical) properties are discussed.

  5. Advanced oxidation protein products are generated by bovine neutrophils and inhibit free radical production in vitro.

    PubMed

    Bordignon, Milena; Da Dalt, Laura; Marinelli, Lieta; Gabai, Gianfranco

    2014-01-01

    Despite the recognised importance of oxidative stress in the health and immune function of dairy cows, protein oxidation markers have been poorly studied in this species. The current study aimed to characterise markers of protein oxidation generated by activated bovine neutrophils and investigate the biological effects of advanced oxidation protein products (AOPP) on bovine neutrophils. Markers of protein oxidation (AOPP, dityrosines and carbonyls) were measured in culture medium containing bovine serum albumin (BSA) exposed to neutrophils. The effect of AOPP-BSA on generation of reactive oxygen species (ROS) was assessed by chemiluminescence. Activation of caspases-3, -8 and -9 and the presence of DNA laddering were used as apoptosis markers. Greater amounts of AOPP were generated by phorbol myristate acetate (PMA)-activated than non-activated neutrophils (1.46 ± 0.13 vs. 0.75 ± 0.13 nmol/mg protein, respectively; P<0.05). Activated neutrophils and hypochlorous acid generated slightly different patterns of oxidized protein markers. Exposure to AOPP-BSA did not stimulate ROS production. Activated neutrophils generated a lesser amount of ROS when incubated with AOPP-BSA (P<0.001). Activation with PMA induced a loss of viable neutrophils after 3h, which was greater with AOPP-BSA incubation (P<0.05). Detectable amounts of active caspases-3, -8 and -9 were found in nearly all samples but differences in caspase activation or DNA laddering were not observed comparing treatment groups. Apoptosis was unlikely to be responsible for the greater loss of PMA-activated neutrophils cultured in AOPP-BSA and it is possible that primary necrosis occurred. The results suggest that accumulation of oxidized proteins at an inflammatory site might result in a progressive reduction of neutrophil viability.

  6. Method for producing highly conformal transparent conducting oxides

    DOEpatents

    Elam, Jeffrey W.; Mane, Anil U.

    2016-07-26

    A method for forming a transparent conducting oxide product layer. The method includes use of precursors, such as tetrakis-(dimethylamino) tin and trimethyl indium, and selected use of dopants, such as SnO and ZnO for obtaining desired optical, electrical and structural properties for a highly conformal layer coating on a substrate. Ozone was also input as a reactive gas which enabled rapid production of the desired product layer.

  7. Method for providing oxygen ion vacancies in lanthanide oxides

    DOEpatents

    Kay, D. Alan R.; Wilson, William G.

    1989-12-05

    A method for desulfurization of fuel gases resulting from the incomplete combustion of sulfur containing hydrocarbons whereby the gases are treated with lanthanide oxides containing large numbers of oxygen-ion vacancies providing ionic porosity which enhances the ability of the lanthanide oxides to react more rapidly and completely with the sulfur in the fuel gases whereby the sulfur in such gases is reduced to low levels suitable for fuels for firing into boilers of power plants generating electricity with steam turbine driven generators, gas turbines, fuel cells and precursors for liquid fuels such as methanol and the like.

  8. Method for catalyzing oxidation/reduction reactions of simple molecules

    SciTech Connect

    Bicker, D.; Bonaventura, J.

    1988-06-14

    A method for oxidizing carbon monoxide to carbon dioxide is described comprising: (1) contacting, together, carbon monoxide, a nitrogen-containing chelating agent and water; wherein the chelating agent is at least one member selected from the group consisting of methmeoglobin bound to a support, ferric hemoglobin bound to a support, iron-containing porphyrins bound to a support, and sperm whale myoglobin bound to a support, wherein the support is glass, a natural fiber, a synthetic fiber, a gel, charcoal, carbon ceramic material, a metal oxide, a synthetic polymer, a zeolite, a silica compound of an alumina compound; and (2) obtaining carbon dioxide.

  9. Method for removal of nitrogen oxides from stationary combustion sources

    NASA Technical Reports Server (NTRS)

    Cooper, Charles D. (Inventor); Clausen, III, Christian A. (Inventor); Collins, Michelle M. (Inventor)

    2004-01-01

    A method for removing NO.sub.X from gas streams emanating from stationary combustion sources and manufacturing plants utilizes the injection of hydrogen peroxide into the gas stream for rapid gas-phase oxidation of NO to NO.sub.2 and water-soluble nitrogen acids HNO.sub.2 and HNO.sub.3. The nitrogen acids may be removed from the oxidized gas stream by wet scrubbing or by contact with a particulate alkaline material to form a nitrite/nitrate salt.

  10. Synthesis of nanocrystalline rare earth oxides by glycothermal method

    SciTech Connect

    Hosokawa, Saburo; Iwamoto, Shinji; Inoue, Masashi

    2008-11-03

    The reaction of yttrium acetate hydrate in 1,2-propanediol at 300 deg. C yielded a product containing acetate groups and glycol moieties. From this product, Y{sub 2}O{sub 3} was directly crystallized at 400 deg. C without the formation of a carbonate oxide phase. The thus-obtained Y{sub 2}O{sub 3} samples had a small crystallite size (2.2 nm) and significantly large surface area (280 m{sup 2}/g). Other nanocrystalline rare earth (Gd-Yb) oxides were also obtained by this method.

  11. Light-induced oxidation in semihard cheeses. Evaluation of methods used to determine levels of oxidation.

    PubMed

    Mortensen, Grith; Sørensen, John; Stapelfeldt, Henrik

    2002-07-17

    Light-induced oxidation in Havarti cheese (38% fat) stored in the dark and exposed to fluorescent light was evaluated by an array of chemical, physical, and spectroscopic methods. Light-induced changes were noticeable already after short exposure times (<12 h). A clear differentiation between samples stored in the dark and samples exposed to 1000 lx fluorescent light was obtained by means of the following methods: color measurements (a values), peroxide value determinations, and evaluations of volatile oxidation products by solid-phase microextraction gas chromatography (SPME-GC). The expected changes in peroxide values in relation to storage time were not evident. Measuring free radicals by electron spin resonance spectrometry could not be done to distinguish between samples, possibly due to the conversion of radicals during sample preparation. However, significant light-exposure effects on secondary oxidation products, detected by SPME-GC, were noted for 1-pentanol, 1-hexanol, nonanal, and benzaldehyde. PMID:12105971

  12. Method for continuous synthesis of metal oxide powders

    SciTech Connect

    Berry, David A.; Haynes, Daniel J.; Shekhawat, Dushyant; Smith, Mark W.

    2015-09-08

    A method for the rapid and continuous production of crystalline mixed-metal oxides from a precursor solution comprised of a polymerizing agent, chelated metal ions, and a solvent. The method discharges solution droplets of less than 500 .mu.m diameter using an atomizing or spray-type process into a reactor having multiple temperature zones. Rapid evaporation occurs in a first zone, followed by mixed-metal organic foam formation in a second zone, followed by amorphous and partially crystalline oxide precursor formation in a third zone, followed by formation of the substantially crystalline mixed-metal oxide in a fourth zone. The method operates in a continuous rather than batch manner and the use of small droplets as the starting material for the temperature-based process allows relatively high temperature processing. In a particular embodiment, the first zone operates at 100-300.degree. C., the second zone operates at 300-700.degree. C., and the third operates at 700-1000.degree. C., and fourth zone operates at at least 700.degree. C. The resulting crystalline mixed-metal oxides display a high degree of crystallinity and sphericity with typical diameters on the order of 50 .mu.m or less.

  13. Advanced characterizations of austenitic oxide dispersion-strengthened (ODS) steels for high-temperature reactor applications

    NASA Astrophysics Data System (ADS)

    Miao, Yinbin

    Future advanced nuclear systems involve higher operation temperatures, intenser neutron flux, and more aggressive coolants, calling for structural materials with excellent performances in multiple aspects. Embedded with densely and dispersedly distributed oxide nanoparticles that are capable of not only pinning dislocations but also trapping radiation-induced defects, oxide dispersion-strengthened (ODS) steels provide excellence in mechanical strength, creep resistance, and radiation tolerance. In order to develop ODS steels with qualifications required by advanced nuclear applications, it is important to understand the fundamental mechanisms of the enhancement of ODS steels in mechanical properties. In this dissertation, a series of austenitic ODS stainless steels were investigated by coordinated state-of-the-art techniques. A series of different precipitate phases, including multiple Y-Ti-O, Y-Al-O, and Y-Ti-Hf-O complex oxides, were observed to form during mechanical alloying. Small precipitates are likely to have coherent or cubic-on-cubic orientation relationships with the matrix, allowing the dislocation to shear through. The Orowan looping mechanism is the dominant particle-dislocation interaction mode as the temperature is low, whereas the shearing mechanism and the Hirsch mechanism are also observed. Interactions between the particles and the dislocations result in the load-partitioning phenomenon. Smaller particles were found to have the stronger loading-partitioning effect. More importantly, the load-partitioning of large size particles are marginal at elevated temperatures, while the small size particles remain sustaining higher load, explaining the excellent high temperature mechanical performance of ODS steels.

  14. Advanced oxidative protein products induced human keratinocyte apoptosis through the NOX-MAPK pathway.

    PubMed

    Sun, Baihui; Ding, Ruoting; Yu, Wenlin; Wu, Yanhong; Wang, Bulin; Li, Qin

    2016-07-01

    Impaired wound healing is a major diabetes-related complication. Keratinocytes play an important role in wound healing. Multiple factors have been proposed that can induce dysfunction in keratinocytes. The focus of present research is at a more specific molecular level. We investigated the role of advanced oxidative protein products (AOPPs) in inducing human immortalized keratinocyte (HaCaT) cell apoptosis and the cellular mechanism underlying the proapoptotic effect of AOPPs. HaCaT cells were treated with increasing concentrations of AOPP-human serum albumin or for increasing time durations. The cell viability was measured using the thiazolyl blue tetrazolium bromide method, and flow cytometry was used to assess the rate of cell apoptosis. A loss of mitochondrial membrane potential (MMP) and an increase in intracellular reactive oxygen species (ROS) were observed through a confocal laser scanning microscope system, and the level of ROS generation was determined using a microplate reader. Nicotinamide adenine dinucleotide phosphate oxidase (NOX)4, extracellular signal-regulated kinase (ERK)1/2, p38 mitogen-activated protein kinase (MAPK), and apoptosis-related downstream protein interactions were investigated using the Western blot analysis. We found that AOPPs triggered HaCaT cell apoptosis and MMP loss. After AOPP treatment, intracellular ROS generation increased in a time- and dose-dependent manner. Proapoptotic proteins, such as Bax, caspase 9/caspase 3, and poly(ADP-ribose) polymerase (PARP)-1 were activated, whereas anti-apoptotic Bcl-2 protein was downregulated. AOPPs also increased NOX4, ERK1/2, and p38 MAPK expression. Taken together, these findings suggest that extracellular AOPP accumulation triggered NOX-dependent ROS production, which activated ERK1/2 and p38 MAPK, and induced HaCaT cell apoptosis by activating caspase 3 and PARP-1.

  15. Method and apparatus for the production of metal oxide powder

    DOEpatents

    Harris, Michael T.; Scott, Timothy C.; Byers, Charles H.

    1993-01-01

    The present invention provides a method for preparing metal oxide powder. A first solution, which is substantially organic, is prepared. A second solution, which is an aqueous solution substantially immiscible in the first solution, is prepared and delivered as drops to the first solution. The drops of the second solution are atomized by a pulsed electric field forming micro-drops of the second solution. Reagents in the first solution diffuse into and react with reactants in the micro-drops of the second solution forming metal hydroxide or oxalate particles. The metal hydroxide or metal oxalate particles are then recovered and dried to produce the metal oxide powder. An apparatus for preparing a metal oxide powder is also disclosed.

  16. Method and apparatus for the production of metal oxide powder

    DOEpatents

    Harris, Michael T.; Scott, Timothy C.; Byers, Charles H.

    1992-01-01

    The present invention provides a method for preparing metal oxide powder. A first solution, which is substantially organic, is prepared. A second solution, which is an aqueous solution substantially immiscible in the first solution, is prepared and delivered as drops to the first solution. The drops of the second solution are atomized by a pulsed electric field forming micro-drops of the second solution. Reagents in the first solution diffuse into and react with reactants in the micro-drops of the second solution forming metal hydroxide or oxalate particles. The metal hydroxide or metal oxalate particles are then recovered and dried to produce the metal oxide powder. An apparatus for preparing a metal oxide powder is also disclosed.

  17. Method and apparatus for the production of metal oxide powder

    DOEpatents

    Harris, M.T.; Scott, T.C.; Byers, C.H.

    1992-06-16

    The present invention provides a method for preparing metal oxide powder. A first solution, which is substantially organic, is prepared. A second solution, which is an aqueous solution substantially immiscible in the first solution, is prepared and delivered as drops to the first solution. The drops of the second solution are atomized by a pulsed electric field forming micro-drops of the second solution. Reagents in the first solution diffuse into and react with reactants in the micro-drops of the second solution forming metal hydroxide or oxalate particles. The metal hydroxide or metal oxalate particles are then recovered and dried to produce the metal oxide powder. An apparatus for preparing a metal oxide powder is also disclosed. 2 figs.

  18. Total reflection X-ray fluorescence trace mercury determination by trapping complexation: Application in advanced oxidation technologies

    NASA Astrophysics Data System (ADS)

    Custo, Graciela; Litter, Marta I.; Rodríguez, Diana; Vázquez, Cristina

    2006-11-01

    It is well known that Hg species cause high noxious effects on the health of living organisms even at very low levels (5 μg/L). Quantification of this element is an analytical challenge due to the peculiar physicochemical properties of all Hg species. The regulation of the maximal allowable Hg concentration led to search for sensitive methods for its determination. Total reflection X-ray fluorescence is a proved instrumental analytical tool for the determination of trace elements. In this work, the use of total reflection X-ray fluorescence for Hg quantification is investigated. However, experimental determination by total reflection X-ray fluorescence requires depositing a small volume of sample on the reflector and evaporation of the solvent until dryness to form a thin film. Because of volatilization of several Hg forms, a procedure to capture these volatile species in liquid samples by using complexing agents is proposed. Acetate, oxalic acid, ethylenediaminetetracetic acid and ammonium pyrrolidine-dithiocarbamate were assayed for trapping the analytes into the solution during the preparation of the sample and onto the reflector during total reflection X-ray fluorescence measurements. The proposed method was applied to evaluate Hg concentration during TiO 2-heterogeneous photocatalysis, one of the most known advanced oxidation technologies. Advanced oxidation technologies are processes for the treatment of effluents in waters and air that involve the generation of very active oxidative and reductive species. In heterogeneous photocatalysis, Hg is transformed to several species under ultraviolet illumination in the presence of titanium dioxide. Total reflection X-ray fluorescence was demonstrated to be applicable in following the extent of the heterogeneous photocatalysis reaction by determining non-transformed Hg in the remaining solution.

  19. Design and characterization of a multi-phase annular falling-film reactor for water treatment using advanced oxidation processes.

    PubMed

    Mehrjouei, Mohammad; Müller, Siegfried; Möller, Detlev

    2013-05-15

    In this work, a laboratory-scale of a 3-phase [(I) immobilized photocatalyst, (II) polluted water and (III) oxygen or ozone] falling-film reactor was designed and developed for heterogenous advanced oxidation processes. Characterization and assessment of the annular falling film reactor for handling different advanced oxidation methods was performed. Degussa P-25 TiO2 particles were immobilized on borosilicate glass (BSG) and polymethylmethacrylate (PMMA) tubes and used as a photocatalyst in this study. The characteristics of the falling film reactor, such as the thickness and distribution of falling films and the level of gas absorption into the liquid falling films, as well as the effect of UVA irradiation on the decomposition of ozone inside the falling film reactor, were studied. The adsorption of a model compound on the surface of the immobilized catalyst was measured and the photoactivity of the immobilized photocatalyst was evaluated for the degradation of the model compound. Oxalic acid was chosen as the model compound in this study.

  20. Advanced statistical methods for the definition of new staging models.

    PubMed

    Kates, Ronald; Schmitt, Manfred; Harbeck, Nadia

    2003-01-01

    Adequate staging procedures are the prerequisite for individualized therapy concepts in cancer, particularly in the adjuvant setting. Molecular staging markers tend to characterize specific, fundamental disease processes to a greater extent than conventional staging markers. At the biological level, the course of the disease will almost certainly involve interactions between multiple underlying processes. Since new therapeutic strategies tend to target specific processes as well, their impact will also involve interactions. Hence, assessment of the prognostic impact of new markers and their utilization for prediction of response to therapy will require increasingly sophisticated statistical tools that are capable of detecting and modeling complicated interactions. Because they are designed to model arbitrary interactions, neural networks offer a promising approach to improved staging. However, the typical clinical data environment poses severe challenges to high-performance survival modeling using neural nets, particularly the key problem of maintaining good generalization. Nonetheless, it turns out that by using newly developed methods to minimize unnecessary complexity in the neural network representation of disease course, it is possible to obtain models with high predictive performance. This performance has been validated on both simulated and real patient data sets. There are important applications for design of studies involving targeted therapy concepts and for identification of the improvement in decision support resulting from new staging markers. In this article, advantages of advanced statistical methods such as neural networks for definition of new staging models will be illustrated using breast cancer as an example.

  1. Isothermal thermogravimetric analysis of soybean oil oxidation correlated to thin film micro-oxidation test methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A method of correlation between the Thin Film Micro-Oxidation (TFMO) test with isothermal thermogravimetric analysis is reported utilizing a soybean oil system. Utilizing a kinetic model, pseudo-rate constants and “activation energy” can be calculated from weight loss data. This model accounts for o...

  2. Biodegradability of iopromide products after UV/H₂O₂ advanced oxidation.

    PubMed

    Keen, Olya S; Love, Nancy G; Aga, Diana S; Linden, Karl G

    2016-02-01

    Iopromide is an X-ray and MRI contrast agent that is virtually non-biodegradable and persistent through typical wastewater treatment processes. This study determined whether molecular transformation of iopromide in a UV/H2O2 advanced oxidation process (AOP) can result in biodegradable products. The experiments used iopromide labeled with carbon-14 on the aromatic ring to trace degradation of iopromide through UV/H2O2 advanced oxidation and subsequent biodegradation. The biotransformation assay tracked the formation of radiolabeled (14)CO2 which indicated full mineralization of the molecule. The results indicated that AOP formed biodegradable iopromide products. There was no (14)C released from the pre-AOP samples, but up to 20% of all radiolabeled carbon transformed into (14)CO2 over the course of 42 days of biodegradation after iopromide was exposed to advanced oxidation (compared to 10% transformation in inactivated post-AOP controls). In addition, the quantum yield of photolysis of iopromide was determined using low pressure (LP) and medium pressure (MP) mercury lamps as 0.069 ± 0.005 and 0.080 ± 0.007 respectively. The difference in the quantum yields for the two UV sources was not statistically significant at the 95% confidence interval (p = 0.08), which indicates the equivalency of using LP or MP UV sources for iopromide treatment. The reaction rate between iopromide and hydroxyl radicals was measured to be (2.5 ± 0.2) × 10(9) M(-1) s(-1). These results indicate that direct photolysis is a dominant degradation pathway in UV/H2O2 AOP treatment of iopromide. Other iodinated contrast media may also become biodegradable after exposure to UV or UV/H2O2.

  3. Biodegradability of iopromide products after UV/H₂O₂ advanced oxidation.

    PubMed

    Keen, Olya S; Love, Nancy G; Aga, Diana S; Linden, Karl G

    2016-02-01

    Iopromide is an X-ray and MRI contrast agent that is virtually non-biodegradable and persistent through typical wastewater treatment processes. This study determined whether molecular transformation of iopromide in a UV/H2O2 advanced oxidation process (AOP) can result in biodegradable products. The experiments used iopromide labeled with carbon-14 on the aromatic ring to trace degradation of iopromide through UV/H2O2 advanced oxidation and subsequent biodegradation. The biotransformation assay tracked the formation of radiolabeled (14)CO2 which indicated full mineralization of the molecule. The results indicated that AOP formed biodegradable iopromide products. There was no (14)C released from the pre-AOP samples, but up to 20% of all radiolabeled carbon transformed into (14)CO2 over the course of 42 days of biodegradation after iopromide was exposed to advanced oxidation (compared to 10% transformation in inactivated post-AOP controls). In addition, the quantum yield of photolysis of iopromide was determined using low pressure (LP) and medium pressure (MP) mercury lamps as 0.069 ± 0.005 and 0.080 ± 0.007 respectively. The difference in the quantum yields for the two UV sources was not statistically significant at the 95% confidence interval (p = 0.08), which indicates the equivalency of using LP or MP UV sources for iopromide treatment. The reaction rate between iopromide and hydroxyl radicals was measured to be (2.5 ± 0.2) × 10(9) M(-1) s(-1). These results indicate that direct photolysis is a dominant degradation pathway in UV/H2O2 AOP treatment of iopromide. Other iodinated contrast media may also become biodegradable after exposure to UV or UV/H2O2. PMID:26433937

  4. Advanced treatment of biologically pretreated coking wastewater by electrochemical oxidation using boron-doped diamond electrodes.

    PubMed

    Zhu, Xiuping; Ni, Jinren; Lai, Peng

    2009-09-01

    Electrochemical oxidation is a promising technology to treatment of bio-refractory wastewater. Coking wastewater contains high concentration of refractory and toxic compounds and the water quality usually cannot meet the discharge standards after conventional biological treatment processes. This paper initially investigated the electrochemical oxidation using boron-doped diamond (BDD) anode for advanced treatment of coking wastewater. Under the experimental conditions (current density 20-60mAcm(-2), pH 3-11, and temperature 20-60 degrees C) using BDD anode, complete mineralization of organic pollutants was almost achieved, and surplus ammonia-nitrogen (NH(3)-N) was further removed thoroughly when pH was not adjusted or at alkaline value. Moreover, the TOC and NH(3)-N removal rates in BDD anode cell were much greater than those in other common anode systems such as SnO(2) and PbO(2) anodes cells. Given the same target to meet the National Discharge Standard of China, the energy consumption of 64kWhkgCOD(-1) observed in BDD anode system was only about 60% as much as those observed in SnO(2) and PbO(2) anode systems. Further investigation revealed that, in BDD anode cell, organic pollutants were mainly degraded by reaction with free hydroxyl radicals and electrogenerated oxidants (S(2)O(8)(2-), H(2)O(2), and other oxidants) played a less important role, while direct electrochemical oxidation and indirect electrochemical oxidation mediated by active chlorine can be negligible. These results showed great potential of BDD anode system in engineering application as a final treatment of coking wastewater.

  5. Post-treatment of reclaimed waste water based on an electrochemical advanced oxidation process

    NASA Technical Reports Server (NTRS)

    Verostko, Charles E.; Murphy, Oliver J.; Hitchens, G. D.; Salinas, Carlos E.; Rogers, Tom D.

    1992-01-01

    The purification of reclaimed water is essential to water reclamation technology life-support systems in lunar/Mars habitats. An electrochemical UV reactor is being developed which generates oxidants, operates at low temperatures, and requires no chemical expendables. The reactor is the basis for an advanced oxidation process in which electrochemically generated ozone and hydrogen peroxide are used in combination with ultraviolet light irradiation to produce hydroxyl radicals. Results from this process are presented which demonstrate concept feasibility for removal of organic impurities and disinfection of water for potable and hygiene reuse. Power, size requirements, Faradaic efficiency, and process reaction kinetics are discussed. At the completion of this development effort the reactor system will be installed in JSC's regenerative water recovery test facility for evaluation to compare this technique with other candidate processes.

  6. Comparison of various advanced oxidation processes for the degradation of phenylurea herbicides.

    PubMed

    Kovács, Krisztina; Farkas, János; Veréb, Gábor; Arany, Eszter; Simon, Gergő; Schrantz, Krisztina; Dombi, András; Hernádi, Klára; Alapi, Tünde

    2016-01-01

    Various types of advanced oxidation processes (AOPs), such as UV photolysis, ozonation, heterogeneous photocatalysis and their combinations were comparatively examined at the same energy input in a home-made reactor. The oxidative transformations of the phenylurea herbicides fenuron, monuron and diuron were investigated. The initial rates of transformation demonstrated that UV photolysis was highly efficient in the cases of diuron and monuron. Ozonation proved to be much more effective in the transformation of fenuron than in those of the chlorine containing monuron and diuron. In heterogeneous photocatalysis, the rate of decomposition decreased with increase of the number of chlorine atoms in the target molecule. Addition of ozone to UV-irradiated solutions and/or TiO2-containing suspensions markedly increased the initial rates of degradation. Dehalogenation of monuron and diuron showed that each of these procedures is suitable for the simultaneous removal of chlorinated pesticides and their chlorinated intermediates. Heterogeneous photocatalysis was found to be effective in the mineralization.

  7. Advanced oxidation process using hydrogen peroxide/microwave system for solubilization of phosphate.

    PubMed

    Liao, Ping Huang; Wong, Wayne T; Lo, Kwang Victor

    2005-01-01

    An advanced oxidation process (AOP) combining hydrogen peroxide and microwave heating was used for the solubilization of phosphate from secondary municipal sludge from an enhanced biological phosphorus removal process. The microwave irradiation is used as a generator agent of oxidizing radicals as well as a heating source in the process. This AOP process could facilitate the release of a large amount of the sludge-bound phosphorus from the sewage sludge. More than 84% of the total phosphorous could be released at a microwave heating time of 5 min at 170 degrees C. This innovative process has the potential of being applied to simple sludge treatment processes in domestic wastewater treatment and to the recovery of phosphorus from the wastewater.

  8. Removal of PCBs in contaminated soils by means of chemical reduction and advanced oxidation processes.

    PubMed

    Rybnikova, V; Usman, M; Hanna, K

    2016-09-01

    Although the chemical reduction and advanced oxidation processes have been widely used individually, very few studies have assessed the combined reduction/oxidation approach for soil remediation. In the present study, experiments were performed in spiked sand and historically contaminated soil by using four synthetic nanoparticles (Fe(0), Fe/Ni, Fe3O4, Fe3 - x Ni x O4). These nanoparticles were tested firstly for reductive transformation of polychlorinated biphenyls (PCBs) and then employed as catalysts to promote chemical oxidation reactions (H2O2 or persulfate). Obtained results indicated that bimetallic nanoparticles Fe/Ni showed the highest efficiency in reduction of PCB28 and PCB118 in spiked sand (97 and 79 %, respectively), whereas magnetite (Fe3O4) exhibited a high catalytic stability during the combined reduction/oxidation approach. In chemical oxidation, persulfate showed higher PCB degradation extent than hydrogen peroxide. As expected, the degradation efficiency was found to be limited in historically contaminated soil, where only Fe(0) and Fe/Ni particles exhibited reductive capability towards PCBs (13 and 18 %). In oxidation step, the highest degradation extents were obtained in presence of Fe(0) and Fe/Ni (18-19 %). The increase in particle and oxidant doses improved the efficiency of treatment, but overall degradation extents did not exceed 30 %, suggesting that only a small part of PCBs in soil was available for reaction with catalyst and/or oxidant. The use of organic solvent or cyclodextrin to improve the PCB availability in soil did not enhance degradation efficiency, underscoring the strong impact of soil matrix. Moreover, a better PCB degradation was observed in sand spiked with extractable organic matter separated from contaminated soil. In contrast to fractions with higher particle size (250-500 and <500 μm), no PCB degradation was observed in the finest fraction (≤250 μm) having higher organic matter content. These findings

  9. Advanced Oxide Material Systems For 1650 C Thermal/Environmental Barrier Coating Applications

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Fox, Dennis S.; Bansal, Narottam P.; Miller, Robert A.

    2004-01-01

    Advanced thermal/environmental barrier coatings (T/EBCs) are being developed for low emission SiC/SiC ceramic matrix composite (CMC) combustor and vane applications to extend the CMC liner and vane temperature capability to 1650 C (3000 F) in oxidizing and water-vapor containing combustion environments. The 1650 C T/EBC system is required to have better thermal stability, lower thermal conductivity, and improved sintering and thermal stress resistance than current coating systems. In this paper, the thermal conductivity, water vapor stability and cyclic durability of selected candidate zirconia-/hafnia-, pyrochlore- and magnetoplumbite-based T/EBC materials are evaluated. The test results have been used to downselect the T/EBC coating materials, and help demonstrate advanced 1650OC coatings feasibility with long-term cyclic durability.

  10. Engineered crumpled graphene oxide nanocomposite membrane assemblies for advanced water treatment processes.

    PubMed

    Jiang, Yi; Wang, Wei-Ning; Liu, Di; Nie, Yao; Li, Wenlu; Wu, Jiewei; Zhang, Fuzhong; Biswas, Pratim; Fortner, John D

    2015-06-01

    In this work, we describe multifunctional, crumpled graphene oxide (CGO) porous nanocomposites that are assembled as advanced, reactive water treatment membranes. Crumpled 3D graphene oxide based materials fundamentally differ from 2D flat graphene oxide analogues in that they are highly aggregation and compression-resistant (i.e., π-π stacking resistant) and allow for the incorporation (wrapping) of other, multifunctional particles inside the 3D, composite structure. Here, assemblies of nanoscale, monomeric CGO with encapsulated (as a quasi core-shell structure) TiO2 (GOTI) and Ag (GOAg) nanoparticles, not only allow high water flux via vertically tortuous nanochannels (achieving water flux of 246 ± 11 L/(m(2)·h·bar) with 5.4 μm thick assembly, 7.4 g/m(2)), outperforming comparable commercial ultrafiltration membranes, but also demonstrate excellent separation efficiencies for model organic and biological foulants. Further, multifunctionality is demonstrated through the in situ photocatalytic degradation of methyl orange (MO), as a model organic, under fast flow conditions (tres < 0.1 s); while superior antimicrobial properties, evaluated with GOAg, are observed for both biofilm (contact) and suspended growth scenarios (>3 log effective removal, Escherichia coli). This is the first demonstration of 3D, crumpled graphene oxide based nanocomposite structures applied specifically as (re)active membrane assemblies and highlights the material's platform potential for a truly tailored approach for next generation water treatment and separation technologies. PMID:25942505

  11. Advanced oxidation of benzene, toluene, ethylbenzene and xylene isomers (BTEX) by Trametes versicolor.

    PubMed

    Aranda, Elisabet; Marco-Urrea, Ernest; Caminal, Gloria; Arias, María E; García-Romera, Inmaculada; Guillén, Francisco

    2010-09-15

    Advanced oxidation of benzene, toluene, ethylbenzene, and o-, m-, and p-xylene (BTEX) by the extracellular hydroxyl radicals (*OH) generated by the white-rot fungus Trametes versicolor is for the first time demonstrated. The production of *OH was induced by incubating the fungus with 2,6-dimethoxy-1,4-benzoquinone (DBQ) and Fe3+-EDTA. Under these conditions, *OH were generated through DBQ redox cycling catalyzed by quinone reductase and laccase. The capability of T. versicolor growing in malt extract medium to produce *OH by this mechanism was shown during primary and secondary metabolism, and was quantitatively modulated by the replacement of EDTA by oxalate and Mn2+ addition to DBQ incubations. Oxidation of BTEX was observed only under *OH induction conditions. *OH involvement was inferred from the high correlation observed between the rates at which they were produced under different DBQ redox cycling conditions and those of benzene removal, and the production of phenol as a typical hydroxylation product of *OH attack on benzene. All the BTEX compounds (500 microM) were oxidized at a similar rate, reaching an average of 71% degradation in 6 h samples. After this time oxidation stopped due to O2 depletion in the closed vials used in the incubations.

  12. Occurrence and Removal of Organic Micropollutants in Landfill Leachates Treated by Electrochemical Advanced Oxidation Processes.

    PubMed

    Oturan, Nihal; van Hullebusch, Eric D; Zhang, Hui; Mazeas, Laurent; Budzinski, Hélène; Le Menach, Karyn; Oturan, Mehmet A

    2015-10-20

    In recent years, electrochemical advanced oxidation processes have been shown to be an effective alternative for the removal of refractory organic compounds from water. This study is focused on the effective removal of recalcitrant organic matter (micropollutants, humic substances, etc.) present in municipal solid waste landfill leachates. A mixture of eight landfill leachates has been studied by the electro-Fenton process using a Pt or boron-doped diamond (BDD) anode and a carbon felt cathode or by the anodic oxidation process with a BDD anode. These processes exhibit great oxidation ability due to the in situ production of hydroxyl radicals ((•)OH), a highly powerful oxidizing species. Both electrochemical processes were shown to be efficient in the removal of dissolved total organic carbon (TOC) from landfill leachates. Regarding the electro-Fenton process, the replacement of the classical anode Pt by the anode BDD allows better performance in terms of dissolved TOC removal. The occurrence and removal yield of 19 polycyclic aromatic hydrocarbons, 15 volatile organic compounds, 7 alkylphenols, 7 polychlorobiphenyls, 5 organochlorine pesticides, and 2 polybrominated diphenyl ethers in landfill leachate were also investigated. Both electrochemical processes allow one to reach a quasicomplete removal (about 98%) of these organic micropollutants.

  13. Occurrence and Removal of Organic Micropollutants in Landfill Leachates Treated by Electrochemical Advanced Oxidation Processes.

    PubMed

    Oturan, Nihal; van Hullebusch, Eric D; Zhang, Hui; Mazeas, Laurent; Budzinski, Hélène; Le Menach, Karyn; Oturan, Mehmet A

    2015-10-20

    In recent years, electrochemical advanced oxidation processes have been shown to be an effective alternative for the removal of refractory organic compounds from water. This study is focused on the effective removal of recalcitrant organic matter (micropollutants, humic substances, etc.) present in municipal solid waste landfill leachates. A mixture of eight landfill leachates has been studied by the electro-Fenton process using a Pt or boron-doped diamond (BDD) anode and a carbon felt cathode or by the anodic oxidation process with a BDD anode. These processes exhibit great oxidation ability due to the in situ production of hydroxyl radicals ((•)OH), a highly powerful oxidizing species. Both electrochemical processes were shown to be efficient in the removal of dissolved total organic carbon (TOC) from landfill leachates. Regarding the electro-Fenton process, the replacement of the classical anode Pt by the anode BDD allows better performance in terms of dissolved TOC removal. The occurrence and removal yield of 19 polycyclic aromatic hydrocarbons, 15 volatile organic compounds, 7 alkylphenols, 7 polychlorobiphenyls, 5 organochlorine pesticides, and 2 polybrominated diphenyl ethers in landfill leachate were also investigated. Both electrochemical processes allow one to reach a quasicomplete removal (about 98%) of these organic micropollutants. PMID:26378656

  14. Combining Advanced Oxidation Processes: Assessment Of Process Additivity, Synergism, And Antagonism

    SciTech Connect

    Peters, Robert W.; Sharma, M.P.; Gbadebo Adewuyi, Yusuf

    2007-07-01

    This paper addresses the process interactions from combining integrated processes (such as advanced oxidation processes (AOPs), biological operations, air stripping, etc.). AOPs considered include: Fenton's reagent, ultraviolet light, titanium dioxide, ozone (O{sub 3}), hydrogen peroxide (H{sub 2}O{sub 2}), sonication/acoustic cavitation, among others. A critical review of the technical literature has been performed, and the data has been analyzed in terms of the processes being additive, synergistic, or antagonistic. Predictions based on the individual unit operations are made and compared against the behavior of the combined unit operations. The data reported in this paper focus primarily on treatment of petroleum hydrocarbons and chlorinated solvents. (authors)

  15. Monolithic solid oxide fuel cell technology advancement for coal- based power generation. Quarterly report, December 1991

    SciTech Connect

    Not Available

    1992-01-15

    The program is conducted by a team consisting of AiResearch Los Angeles Division of Allied-Signal Aerospace Company and Argonne National Laboratory (ANL). The objective of the program is to advance materials and fabrication methodologies to develop a monolithic solid oxide fuel cell (MSOFC) system capable of meeting performance, life, and cost goals for coal-based power generation. The program focuses on materials research and development, fabrication process development, cell/stack performance testing and characterization, cost and system analysis, and quality development.

  16. Monolithic solid oxide fuel cell technology advancement for coal- based power generation

    SciTech Connect

    Not Available

    1992-01-15

    The program is conducted by a team consisting of AiResearch Los Angeles Division of Allied-Signal Aerospace Company and Argonne National Laboratory (ANL). The objective of the program is to advance materials and fabrication methodologies to develop a monolithic solid oxide fuel cell (MSOFC) system capable of meeting performance, life, and cost goals for coal-based power generation. The program focuses on materials research and development, fabrication process development, cell/stack performance testing and characterization, cost and system analysis, and quality development.

  17. Recent advances in synthesis and surface modification of superparamagnetic iron oxide nanoparticles with silica

    NASA Astrophysics Data System (ADS)

    Sodipo, Bashiru Kayode; Aziz, Azlan Abdul

    2016-10-01

    Research on synthesis of superparamagnetic iron oxide nanoparticles (SPION) and its surface modification for biomedical applications is of intense interest. Due to superparamagnetic property of SPION, the nanoparticles have large magnetic susceptibility, single magnetic domain and controllable magnetic behaviour. However, owing to easy agglomeration of SPION, surface modification of the magnetic particles with biocompatible materials such as silica nanoparticle has gained much attention in the last decade. In this review, we present recent advances in synthesis of SPION and various routes of producing silica coated SPION.

  18. Controlled decomposition and oxidation: A treatment method for gaseous process effluents

    NASA Technical Reports Server (NTRS)

    Mckinley, Roger J. B., Sr.

    1990-01-01

    The safe disposal of effluent gases produced by the electronics industry deserves special attention. Due to the hazardous nature of many of the materials used, it is essential to control and treat the reactants and reactant by-products as they are exhausted from the process tool and prior to their release into the manufacturing facility's exhaust system and the atmosphere. Controlled decomposition and oxidation (CDO) is one method of treating effluent gases from thin film deposition processes. CDO equipment applications, field experience, and results of the use of CDO equipment and technological advances gained from the field experiences are discussed.

  19. Underwater Photosynthesis of Submerged Plants – Recent Advances and Methods

    PubMed Central

    Pedersen, Ole; Colmer, Timothy D.; Sand-Jensen, Kaj

    2013-01-01

    We describe the general background and the recent advances in research on underwater photosynthesis of leaf segments, whole communities, and plant dominated aquatic ecosystems and present contemporary methods tailor made to quantify photosynthesis and carbon fixation under water. The majority of studies of aquatic photosynthesis have been carried out with detached leaves or thalli and this selectiveness influences the perception of the regulation of aquatic photosynthesis. We thus recommend assessing the influence of inorganic carbon and temperature on natural aquatic communities of variable density in addition to studying detached leaves in the scenarios of rising CO2 and temperature. Moreover, a growing number of researchers are interested in tolerance of terrestrial plants during flooding as torrential rains sometimes result in overland floods that inundate terrestrial plants. We propose to undertake studies to elucidate the importance of leaf acclimation of terrestrial plants to facilitate gas exchange and light utilization under water as these acclimations influence underwater photosynthesis as well as internal aeration of plant tissues during submergence. PMID:23734154

  20. Quantifying hydrate solidification front advancing using method of characteristics

    NASA Astrophysics Data System (ADS)

    You, Kehua; DiCarlo, David; Flemings, Peter B.

    2015-10-01

    We develop a one-dimensional analytical solution based on the method of characteristics to explore hydrate formation from gas injection into brine-saturated sediments within the hydrate stability zone. Our solution includes fully coupled multiphase and multicomponent flow and the associated advective transport in a homogeneous system. Our solution shows that hydrate saturation is controlled by the initial thermodynamic state of the system and changed by the gas fractional flow. Hydrate saturation in gas-rich systems can be estimated by 1-cl0/cle when Darcy flow dominates, where cl0 is the initial mass fraction of salt in brine, and cle is the mass fraction of salt in brine at three-phase (gas, liquid, and hydrate) equilibrium. Hydrate saturation is constant, gas saturation and gas flux decrease, and liquid saturation and liquid flux increase with the distance from the gas inlet to the hydrate solidification front. The total gas and liquid flux is constant from the gas inlet to the hydrate solidification front and decreases abruptly at the hydrate solidification front due to gas inclusion into the hydrate phase. The advancing velocity of the hydrate solidification front decreases with hydrate saturation at a fixed gas inflow rate. This analytical solution illuminates how hydrate is formed by gas injection (methane, CO2, ethane, propane) at both the laboratory and field scales.

  1. Regenerative medicine: advances in new methods and technologies.

    PubMed

    Park, Dong-Hyuk; Eve, David J

    2009-11-01

    The articles published in the journal Cell Transplantation - The Regenerative Medicine Journal over the last two years reveal the recent and future cutting-edge research in the fields of regenerative and transplantation medicine. 437 articles were published from 2007 to 2008, a 17% increase compared to the 373 articles in 2006-2007. Neuroscience was still the most common section in both the number of articles and the percentage of all manuscripts published. The increasing interest and rapid advance in bioengineering technology is highlighted by tissue engineering and bioartificial organs being ranked second again. For a similar reason, the methods and new technologies section increased significantly compared to the last period. Articles focusing on the transplantation of stem cell lineages encompassed almost 20% of all articles published. By contrast, the non-stem cell transplantation group which is made up primarily of islet cells, followed by biomaterials and fetal neural tissue, etc. comprised less than 15%. Transplantation of cells pre-treated with medicine or gene transfection to prolong graft survival or promote differentiation into the needed phenotype, was prevalent in the transplantation articles regardless of the kind of cells used. Meanwhile, the majority of non-transplantation-based articles were related to new devices for various purposes, characterization of unknown cells, medicines, cell preparation and/or optimization for transplantation (e.g. isolation and culture), and disease pathology.

  2. Method of preventing oxidation of graphite fireproof material

    NASA Technical Reports Server (NTRS)

    Yamauchi, S.; Suzuki, H.

    1981-01-01

    A method of preventing oxidation of graphite fireproof material is given. A blend of 1 to 33 weight parts alumina and 3 to 19 parts of K2O + Na2O in 100 parts of SiO2 is pulverized followed by addition of 5 to 160 parts of silicon carbide powder in 100 parts of the mixture. This is thoroughly blended and coated on the surface of graphite fireproof material.

  3. Advanced diagnostic methods in oral and maxillofacial pathology. Part II: immunohistochemical and immunofluorescent methods.

    PubMed

    Jordan, Richard C K; Daniels, Troy E; Greenspan, John S; Regezi, Joseph A

    2002-01-01

    The practice of pathology is currently undergoing significant change, in large part due to advances in the analysis of DNA, RNA, and proteins in tissues. These advances have permitted improved biologic insights into many developmental, inflammatory, metabolic, infectious, and neoplastic diseases. Moreover, molecular analysis has also led to improvements in the accuracy of disease diagnosis and classification. It is likely that, in the future, these methods will increasingly enter into the day-to-day diagnosis and management of patients. The pathologist will continue to play a fundamental role in diagnosis and will likely be in a pivotal position to guide the implementation and interpretation of these tests as they move from the research laboratory into diagnostic pathology. The purpose of this 2-part series is to provide an overview of the principles and applications of current molecular biologic and immunologic tests. In Part I, the biologic fundamentals of DNA, RNA, and proteins and methods that are currently available or likely to become available to the pathologist in the next several years for their isolation and analysis in tissue biopsies were discussed. In Part II, advances in immunohistochemistry and immunofluorescence methods and their application to modern diagnostic pathology are reviewed. PMID:11805778

  4. Advanced TEM specimen preparation methods for replication of P91 steel

    SciTech Connect

    Mitchell, D.R.G. . E-mail: drm@ansto.gov.au; Sulaiman, S.

    2006-01-15

    A range of advanced transmission electron microscopy specimen preparation methods, based on replication, have been developed for P91 steel. The results obtained have been compared with conventional replication and thin foil methods. The aim has been to obtain complimentary information from thin foil and replica specimens from the same region of interest either sequentially or simultaneously. The effects of various reagents for dissolution of the steel matrix and replica release have been investigated, and chemical methods for removing amorphous iron oxide contaminants from replicas have been identified. A method of region-specific replication is demonstrated whereby regions of thin foils previously characterised by TEM, can be subsequently replicated. This enables the former location of extracted particles, such as on grain/lath/subgrain boundaries etc., to be determined prior to microanalysis. It also permits the identification of artefacts such as stray particles and failed extractions. A second method of thin foil partial replication was developed in which both replica and thin foil are present on the same specimen. At the interface between the two regions, thin foil information such as dislocation interactions with fine scale particles and replica information such as microanalysis of particles within the same grain or lath can be obtained. Double replication of thin foils has also been successfully demonstrated. These methods are applied to a creep resistant martensitic steel (P91), but should be broadly applicable to a wide range of alloy steels.

  5. Advanced Fabrication Method for the Preparation of MOF Thin Films: Liquid-Phase Epitaxy Approach Meets Spin Coating Method.

    PubMed

    Chernikova, Valeriya; Shekhah, Osama; Eddaoudi, Mohamed

    2016-08-10

    Here, we report a new and advanced method for the fabrication of highly oriented/polycrystalline metal-organic framework (MOF) thin films. Building on the attractive features of the liquid-phase epitaxy (LPE) approach, a facile spin coating method was implemented to generate MOF thin films in a high-throughput fashion. Advantageously, this approach offers a great prospective to cost-effectively construct thin-films with a significantly shortened preparation time and a lessened chemicals and solvents consumption, as compared to the conventional LPE-process. Certainly, this new spin-coating approach has been implemented successfully to construct various MOF thin films, ranging in thickness from a few micrometers down to the nanometer scale, spanning 2-D and 3-D benchmark MOF materials including Cu2(bdc)2·xH2O, Zn2(bdc)2·xH2O, HKUST-1, and ZIF-8. This method was appraised and proved effective on a variety of substrates comprising functionalized gold, silicon, glass, porous stainless steel, and aluminum oxide. The facile, high-throughput and cost-effective nature of this approach, coupled with the successful thin film growth and substrate versatility, represents the next generation of methods for MOF thin film fabrication. Therefore, paving the way for these unique MOF materials to address a wide range of challenges in the areas of sensing devices and membrane technology. PMID:27415640

  6. Determination of an Effective Perfluorinated Compounds (PFCs) Oxidation Method

    NASA Astrophysics Data System (ADS)

    Siriwardena, D. P.; Crimi, M.; Holsen, T.; Bellona, C.

    2014-12-01

    Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a stable synthetic class of chemicals ubiquitously spread in environmental media (i.e. air, soil, biota, surface water and groundwater). The substances' strong polar carbon-fluorine bonds and their high thermal and chemical stability make them resistant to biological, chemical, and physical degradation. The purpose of this research is to identify the most effective oxidation method to treat perfluorinated compounds (PFCs) and their by-products that is suitable for in situ application. The laboratory oxidation study focuses on the more commonly detected and studied long-chain (C-8) PFAS; perfluorooctanoic acids (PFOA) and perfluorooctane sulfonic acid (PFOS). Existing research evaluating oxidizing treatment effectiveness on perfluoroalkyl sulfoinoic acids (PFSAs) is limited. A review of the literature and results from preliminary studies indicate that activated persulfate and catalyzed hydrogen peroxide propagation (CHP) reactions appear to be promising oxidants for PFOA. It has been demonstrated that the reactivity of superoxide in water increases in the presence of hydrogen peroxide (H2O2) and solids. Superoxide generated in CHP reactions degrades PFOA seemingly similar to superoxide-mediated destruction of the perhalogenated compounds.The goal of this study is to look at conditions that promote generation of superoxide and look at PFASs treatment effectiveness and byproduct generation. CHP reactions are conducted with varying amount of H2O2 and Fe(III) to determine the optimum conditions for PFC degradation. Results will be compared to those of another experiment using manganese dioxide as a CHP catalyst with varied H2O2 concentration to generate superoxide to degrade PFASs. Activated persulfate conditions to be compared include alkaline pH activation, heat activation, and dual oxidation (combined H2O2 and persulfate ). This presentation will focus on a comparison of oxidation effectiveness under the

  7. Development and Applications of Advanced Electronic Structure Methods

    NASA Astrophysics Data System (ADS)

    Bell, Franziska

    This dissertation contributes to three different areas in electronic structure theory. The first part of this thesis advances the fundamentals of orbital active spaces. Orbital active spaces are not only essential in multi-reference approaches, but have also become of interest in single-reference methods as they allow otherwise intractably large systems to be studied. However, despite their great importance, the optimal choice and, more importantly, their physical significance are still not fully understood. In order to address this problem, we studied the higher-order singular value decomposition (HOSVD) in the context of electronic structure methods. We were able to gain a physical understanding of the resulting orbitals and proved a connection to unrelaxed natural orbitals in the case of Moller-Plesset perturbation theory to second order (MP2). In the quest to find the optimal choice of the active space, we proposed a HOSVD for energy-weighted integrals, which yielded the fastest convergence in MP2 correlation energy for small- to medium-sized active spaces to date, and is also potentially transferable to coupled-cluster theory. In the second part, we studied monomeric and dimeric glycerol radical cations and their photo-induced dissociation in collaboration with Prof. Leone and his group. Understanding the mechanistic details involved in these processes are essential for further studies on the combustion of glycerol and carbohydrates. To our surprise, we found that in most cases, the experimentally observed appearance energies arise from the separation of product fragments from one another rather than rearrangement to products. The final chapters of this work focus on the development, assessment, and application of the spin-flip method, which is a single-reference approach, but capable of describing multi-reference problems. Systems exhibiting multi-reference character, which arises from the (near-) degeneracy of orbital energies, are amongst the most

  8. Method of preparing doped oxide catalysts for lean NOx exhaust

    DOEpatents

    Park, Paul W.

    2004-03-09

    The lean NOx catalyst includes a substrate, an oxide support material, preferably .gamma.-alumina deposited on the substrate and a metal or metal oxide promoter or dopant introduced into the oxide support material. The metal promoters or dopants are selected from the group consisting of indium, gallium, tin, silver, germanium, gold, nickel, cobalt, copper, iron, manganese, molybdenum, chromium cerium, and vanadium, and oxides thereof, and any combinations thereof. The .gamma.-alumina preferably has a pore volume of from about 0.5 to about 2.0 cc/g; a surface area of between 80 and 350 m.sup.2 /g; an average pore size diameter of between about 3 to 30 nm; and an impurity level of less than or equal to about 0.2 weight percent. In a preferred embodiment the .gamma.-alumina is prepared by a sol-gel method, with the metal doping of the .gamma.-alumina preferably accomplished using an incipient wetness impregnation technique.

  9. Methods of measuring adhesion for thermally grown oxide scales

    SciTech Connect

    Hou, P.Y.; Atkinson, A.

    1994-06-01

    High temperature alloys and coatings rely on the formation of adherent scales to protect against further oxidation, but scale spallation is often problematic. Despite the technical importance of the problem, ``practical adhesion``, which refers to the separation of the oxide from the metal, has mainly been treated qualitatively in the past. Various techniques now exist such that the subject can be assessed in quantitative or semi-quantitative terms. Some of the techniques are described in this paper, and their weakness and strength are discussed. The experimental methods addressed here include: tensile pulling, micro-indentation, scratch test, residual stress induced delamination, laser or shock wave induced spallation, double cantilever beam and several 4-point beam bending approaches. To date, there is not an universal, easy test for oxide adhesion measurement that can provide reproducible information on interfacial fracture energy for a variety of oxide/metal systems. Much experimentation is still needed to increase confidence in many of the existing tests, and the fundamental mechanics for some present techniques also require further development.

  10. Recent Advances in Modeling Transition Metal Oxides for Photo-electrochemistry

    NASA Astrophysics Data System (ADS)

    Caspary Toroker, Maytal

    Computational research offers a wide range of opportunities for materials science and engineering, especially in the energy arena where there is a need for understanding how material composition and structure control energy conversion, and for designing materials that could improve conversion efficiency. Potential inexpensive materials for energy conversion devices are metal oxides. However, their conversion efficiency is limited by at least one of several factors: a too large band gap for efficiently absorbing solar energy, similar conduction and valence band edge characters that may lead to unfavorably high electron-hole recombination rates, a valence band edge that is not positioned well for oxidizing water, low stability, low electronic conductivity, and low surface reactivity. I will show how we model metal oxides with ab-initio methods, primarily DFT +U. Our previous results show that doping with lithium, sodium, or hydrogen could improve iron (II) oxide's electronic properties, and alloying with zinc or nickel could improve iron (II) oxide's optical properties. Furthermore, doping nickel (II) oxide with lithium could improve several key properties including solar energy absorption. In this talk I will highlight new results on our understanding of the mechanism of iron (III) oxide's surface reactivity. Our theoretical insights bring us a step closer towards understanding how to design better materials for photo-electrochemistry. References: 1. O. Neufeld and M. Caspary Toroker, ``Pt-doped Fe2O3 for enhanced water splitting efficiency: a DFT +U study'', J. Phys. Chem. C 119, 5836 (2015). 2. M. Caspary Toroker, ``Theoretical Insights into the Mechanism of Water Oxidation on Non-stoichiometric and Ti - doped Fe2O3 (0001)'', J. Phys. Chem. C, 118, 23162 (2014). This research was supported by the Morantz Energy Research Fund, the Nancy and Stephen Grand Technion Energy Program, the I-CORE Program of the Planning and Budgeting Committee, and The Israel Science

  11. Chemical oxygen demand reduction in coffee wastewater through chemical flocculation and advanced oxidation processes.

    PubMed

    Zayas Pérez, Teresa; Geissler, Gunther; Hernandez, Fernando

    2007-01-01

    The removal of the natural organic matter present in coffee processing wastewater through chemical coagulation-flocculation and advanced oxidation processes (AOP) had been studied. The effectiveness of the removal of natural organic matter using commercial flocculants and UV/H2O2, UV/O3 and UV/H2O2/O3 processes was determined under acidic conditions. For each of these processes, different operational conditions were explored to optimize the treatment efficiency of the coffee wastewater. Coffee wastewater is characterized by a high chemical oxygen demand (COD) and low total suspended solids. The outcomes of coffee wastewater treatment using coagulation-flocculation and photodegradation processes were assessed in terms of reduction of COD, color, and turbidity. It was found that a reduction in COD of 67% could be realized when the coffee wastewater was treated by chemical coagulation-flocculation with lime and coagulant T-1. When coffee wastewater was treated by coagulation-flocculation in combination with UV/H2O2, a COD reduction of 86% was achieved, although only after prolonged UV irradiation. Of the three advanced oxidation processes considered, UV/H2O2, UV/O3 and UV/H2O2/O3, we found that the treatment with UV/H2O2/O3 was the most effective, with an efficiency of color, turbidity and further COD removal of 87%, when applied to the flocculated coffee wastewater.

  12. Degradation of estrone in water and wastewater by various advanced oxidation processes.

    PubMed

    Sarkar, Shubhajit; Ali, Sura; Rehmann, Lars; Nakhla, George; Ray, Madhumita B

    2014-08-15

    A comprehensive study was conducted to determine the relative efficacy of various advanced oxidation processes such as O3, H2O2, UV, and combinations of UV/O3, UV/H2O2 for the removal of estrone (E1) from pure water and secondary effluent. In addition to the parent compound (E1) removal, performance of the advanced oxidation processes was characterized using removal of total organic carbon (TOC), and estrogenicity of the effluent. Although E1 removal was high for all the AOPs, intermediates formed were more difficult to degrade leading to slow TOC removal. Energy calculations and cost analysis indicated that, although UV processes have low electricity cost, ozonation is the least cost option ($ 0.34/1000 gallons) when both capital and operating costs were taken into account. Ozonation also is superior to the other tested AOPs due to higher removal of TOC and estrogenicity. The rate of E1 removal decreased linearly with the background TOC in water, however, E1 degradation in the secondary effluent from a local wastewater treatment plant was not affected significantly due to the low COD values in the effluent.

  13. Inactivation of adenovirus using low-dose UV/H2O2 advanced oxidation.

    PubMed

    Bounty, Sarah; Rodriguez, Roberto A; Linden, Karl G

    2012-12-01

    Adenovirus has consistently been observed to be the most resistant known pathogen to disinfection by ultraviolet light. This has had an impact on regulations set by the United States Environmental Protection Agency regarding the use of UV disinfection for virus inactivation in groundwater and surface water. In this study, enhancement of UV inactivation of adenovirus was evaluated when hydrogen peroxide was added to create an advanced oxidation process (AOP). While 4 log reduction of adenovirus was determined to require a UV dose (UV fluence) of about 200 mJ/cm(2) from a low pressure (LP) UV source (emitting at 253.7 nm), addition of 10 mg/L H(2)O(2) achieved 4 log inactivation at a dose of 120 mJ/cm(2). DNA damage was assessed using a novel nested PCR approach, and similar levels of DNA damage between the two different treatments were noted, suggesting the AOP enhancement in inactivation was not due to additional DNA damage. Hydroxyl radicals produced in the advanced oxidation process are likely able to damage parts of the virus not targeted by LPUV, such as attachment proteins, enhancing the UV-induced inactivation. The AOP-enhanced inactivation potential was modeled in three natural waters. This research sheds light on the inactivation mechanisms of viruses with ultraviolet light and in the presence of hydroxyl radicals and provides a practical means to enhance inactivation of this UV-resistant virus.

  14. Drinking water treatment of priority pesticides using low pressure UV photolysis and advanced oxidation processes.

    PubMed

    Sanches, Sandra; Barreto Crespo, Maria T; Pereira, Vanessa J

    2010-03-01

    This study reports the efficiency of low pressure UV photolysis for the degradation of pesticides identified as priority pollutants by the European Water Framework Directive 2000/60/EC. Direct low pressure UV photolysis and advanced oxidation processes (using hydrogen peroxide and titanium dioxide) experiments were conducted in laboratory grade water, surface water, and groundwater. LP direct photolysis using a high UV fluence (1500 mJ/cm(2)) was found to be extremely efficient to accomplish the degradation of all pesticides except isoproturon, whereas photolysis using hydrogen peroxide and titanium dioxide did not significantly enhance their removal. In all matrices tested the experimental photolysis of the pesticides followed the same trend: isoproturon degradation was negligible, alachlor, pentachlorophenol, and atrazine showed similar degradation rate constants, whereas diuron and chlorfenvinphos were highly removed. The degradation trend observed for the selected compounds followed the decadic molar absorption coefficients order with exception of isoproturon probably due to its extremely low quantum yield. Similar direct photolysis rate constants were obtained for each pesticide in the different matrices tested, showing that the water components did not significantly impact degradation. Extremely similar photolysis rate constants were also obtained in surface water for individual compounds when compared to mixtures. The model fluence and time-based rate constants reported were very similar to the direct photolysis experimental results obtained, while overestimating the advanced oxidation results. This model was used to predict how degradation of isoproturon, the most resilient compound, could be improved.

  15. Comparison of topotactic fluorination methods for complex oxide films

    SciTech Connect

    Moon, E. J. Choquette, A. K.; Huon, A.; Kulesa, S. Z.; May, S. J.; Barbash, D.

    2015-06-01

    We have investigated the synthesis of SrFeO{sub 3−α}F{sub γ} (α and γ ≤ 1) perovskite films using topotactic fluorination reactions utilizing poly(vinylidene fluoride) as a fluorine source. Two different fluorination methods, a spin-coating and a vapor transport approach, were performed on as-grown SrFeO{sub 2.5} films. We highlight differences in the structural, compositional, and optical properties of the oxyfluoride films obtained via the two methods, providing insight into how fluorination reactions can be used to modify electronic and optical behavior in complex oxide heterostructures.

  16. Methods of Nitrogen Oxide Reduction in Pellet Boilers

    NASA Astrophysics Data System (ADS)

    Zandeckis, Aivars; Blumberga, Dagnija; Rochas, Claudio; Veidenbergs, Ivars; Silins, Kaspars

    2010-01-01

    The main goal of this research was to create and test technical solutions that reduce nitrogen oxide emissions in low-capacity pellet boiler. During the research, wood pellets were incinerated in a pellet boiler produced in Latvia with a rated capacity of 15 kW. During the research two NOx emission reduction methods were tested: secondary air supply in the chamber and recirculation of flue gases. Results indicated a drop of NOx concentration only for flue gas recirculation methods. Maximum reduction of 21% was achieved.

  17. Bioinformatics Methods and Tools to Advance Clinical Care

    PubMed Central

    Lecroq, T.

    2015-01-01

    Summary Objectives To summarize excellent current research in the field of Bioinformatics and Translational Informatics with application in the health domain and clinical care. Method We provide a synopsis of the articles selected for the IMIA Yearbook 2015, from which we attempt to derive a synthetic overview of current and future activities in the field. As last year, a first step of selection was performed by querying MEDLINE with a list of MeSH descriptors completed by a list of terms adapted to the section. Each section editor has evaluated separately the set of 1,594 articles and the evaluation results were merged for retaining 15 articles for peer-review. Results The selection and evaluation process of this Yearbook’s section on Bioinformatics and Translational Informatics yielded four excellent articles regarding data management and genome medicine that are mainly tool-based papers. In the first article, the authors present PPISURV a tool for uncovering the role of specific genes in cancer survival outcome. The second article describes the classifier PredictSNP which combines six performing tools for predicting disease-related mutations. In the third article, by presenting a high-coverage map of the human proteome using high resolution mass spectrometry, the authors highlight the need for using mass spectrometry to complement genome annotation. The fourth article is also related to patient survival and decision support. The authors present datamining methods of large-scale datasets of past transplants. The objective is to identify chances of survival. Conclusions The current research activities still attest the continuous convergence of Bioinformatics and Medical Informatics, with a focus this year on dedicated tools and methods to advance clinical care. Indeed, there is a need for powerful tools for managing and interpreting complex, large-scale genomic and biological datasets, but also a need for user-friendly tools developed for the clinicians in their

  18. Stability of 6:2 fluorotelomer sulfonate in advanced oxidation processes: degradation kinetics and pathway.

    PubMed

    Yang, Xiaoling; Huang, Jun; Zhang, Kunlun; Yu, Gang; Deng, Shubo; Wang, Bin

    2014-03-01

    Perfluorooctane sulfonate (PFOS), a widely used mist suppressant in hard chrome electroplating industry, has been listed in the Stockholm Convention for global ban. 6:2 Fluorotelomer sulfonate (6:2 FTS) acid and salts have been adopted as alternative products in the market, but no data about their abiotic degradation has been reported. In the present study, the degradability of 6:2 FTS potassium salt (6:2 FTS-K) was evaluated under various advanced oxidation processes, including ultraviolet (UV) irradiation, UV with hydrogen peroxide (H2O2), alkaline ozonation (O3, pH = 11), peroxone (O3/H2O2), and Fenton reagent oxidation (Fe(2+)/H2O2). UV/H2O2 was found to be the most effective approach, where the degradation of 6:2 FTS-K followed the pseudo-first-order kinetics. The intermediates were mainly shorter chain perfluoroalkyl carboxylic acid (C7 to C2), while sulfate (SO4 (2-)) and fluoride (F(-)) were found to be the final products. The high yields of SO4 (2-) and F(-) indicate that 6:2 FTS-K can be nearly completely desulfonated and defluorinated under UV/H2O2 condition. The degradation should firstly begin with the substitution of hydrogen atom by hydroxyl radicals, followed by desulfonation, carboxylation, and sequential "flake off" of CF2 unit. Compared with PFOS which is inert in most advanced oxidation processes, 6:2 FTS-K is more degradable as the alternative.

  19. ADVANCED SEISMIC BASE ISOLATION METHODS FOR MODULAR REACTORS

    SciTech Connect

    E. Blanford; E. Keldrauk; M. Laufer; M. Mieler; J. Wei; B. Stojadinovic; P.F. Peterson

    2010-09-20

    Advanced technologies for structural design and construction have the potential for major impact not only on nuclear power plant construction time and cost, but also on the design process and on the safety, security and reliability of next generation of nuclear power plants. In future Generation IV (Gen IV) reactors, structural and seismic design should be much more closely integrated with the design of nuclear and industrial safety systems, physical security systems, and international safeguards systems. Overall reliability will be increased, through the use of replaceable and modular equipment, and through design to facilitate on-line monitoring, in-service inspection, maintenance, replacement, and decommissioning. Economics will also receive high design priority, through integrated engineering efforts to optimize building arrangements to minimize building heights and footprints. Finally, the licensing approach will be transformed by becoming increasingly performance based and technology neutral, using best-estimate simulation methods with uncertainty and margin quantification. In this context, two structural engineering technologies, seismic base isolation and modular steel-plate/concrete composite structural walls, are investigated. These technologies have major potential to (1) enable standardized reactor designs to be deployed across a wider range of sites, (2) reduce the impact of uncertainties related to site-specific seismic conditions, and (3) alleviate reactor equipment qualification requirements. For Gen IV reactors the potential for deliberate crashes of large aircraft must also be considered in design. This report concludes that base-isolated structures should be decoupled from the reactor external event exclusion system. As an example, a scoping analysis is performed for a rectangular, decoupled external event shell designed as a grillage. This report also reviews modular construction technology, particularly steel-plate/concrete construction using

  20. Recent Progress in Self‐Supported Metal Oxide Nanoarray Electrodes for Advanced Lithium‐Ion Batteries

    PubMed Central

    Zhang, Feng

    2016-01-01

    The rational design and fabrication of electrode materials with desirable architectures and optimized properties has been demonstrated to be an effective approach towards high‐performance lithium‐ion batteries (LIBs). Although nanostructured metal oxide electrodes with high specific capacity have been regarded as the most promising alternatives for replacing commercial electrodes in LIBs, their further developments are still faced with several challenges such as poor cycling stability and unsatisfying rate performance. As a new class of binder‐free electrodes for LIBs, self‐supported metal oxide nanoarray electrodes have many advantageous features in terms of high specific surface area, fast electron transport, improved charge transfer efficiency, and free space for alleviating volume expansion and preventing severe aggregation, holding great potential to solve the mentioned problems. This review highlights the recent progress in the utilization of self‐supported metal oxide nanoarrays grown on 2D planar and 3D porous substrates, such as 1D and 2D nanostructure arrays, hierarchical nanostructure arrays, and heterostructured nanoarrays, as anodes and cathodes for advanced LIBs. Furthermore, the potential applications of these binder‐free nanoarray electrodes for practical LIBs in full‐cell configuration are outlined. Finally, the future prospects of these self‐supported nanoarray electrodes are discussed. PMID:27711259

  1. Toxicological and chemical assessment of arsenic-contaminated groundwater after electrochemical and advanced oxidation treatments.

    PubMed

    Radić, Sandra; Crnojević, Helena; Vujčić, Valerija; Gajski, Goran; Gerić, Marko; Cvetković, Želimira; Petra, Cvjetko; Garaj-Vrhovac, Vera; Oreščanin, Višnja

    2016-02-01

    Owing to its proven toxicity and mutagenicity, arsenic is regarded a principal pollutant in water used for drinking. The objective of this study was the toxicological and chemical evaluation of groundwater samples obtained from arsenic enriched drinking water wells before and after electrochemical and ozone-UV-H2O2-based advanced oxidation processes (EAOP). For this purpose, acute toxicity test with Daphnia magna and chronic toxicity test with Lemna minor L. were employed as well as in vitro bioassays using human peripheral blood lymphocytes (HPBLs). Several oxidative stress parameters were estimated in L.minor. Physicochemical analysis showed that EAOP treatment was highly efficient in arsenic but also in ammonia and organic compound removal from contaminated groundwater. Untreated groundwater caused only slight toxicity to HPBLs and D. magna in acute experiments. However, 7-day exposure of L. minor to raw groundwater elicited genotoxicity, a significant growth inhibition and oxidative stress injury. The observed genotoxicity and toxicity of raw groundwater samples was almost completely eliminated by EAOP treatment. Generally, the results obtained with L. minor were in agreement with those obtained in the chemical analysis suggesting the sensitivity of the model organism in monitoring of arsenic-contaminated groundwater. In parallel to chemical analysis, the implementation of chronic toxicity bioassays in a battery is recommended in the assessment of the toxic and genotoxic potential of such complex mixtures.

  2. Comparison of advanced oxidation processes for the removal of natural organic matter.

    PubMed

    Lamsal, Rupa; Walsh, Margaret E; Gagnon, Graham A

    2011-05-01

    This study examined the impact of UV, ozone (O(3)), advanced oxidation processes (AOPs) including O(3)/UV, H(2)O(2)/UV H(2)O(2)/O(3) in the change of molecular weight distribution (MWD) and disinfection by-product formation potential (DBPFP). Bench-scale experiments were conducted with surface river water and changes in the UV absorbance at 254 nm (UV(254)), total organic carbon (TOC), trihalomethane and haloacetic acid formation potential (THMFP, HAAFP) and MWD of the raw and oxidized water were analyzed to evaluate treatment performance. Combination of O(3) and UV with H(2)O(2) was found to result in more TOC and UV(254) reduction than the individual processes. The O(3)/UV process was found to be the most effective AOP for NOM reduction, with TOC and UV(254) reduced by 31 and 88%, respectively. Application of O(3)/UV and H(2)O(2)/UV treatments to the source waters organics with 190-1500 Da molecular weight resulted in the near complete alteration of the molecular weight of NOM from >900 Da to <300 Da H(2)O(2)/UV was found to be the most effective treatment for the reduction of THM and HAA formation under uniform formation conditions. These results could hold particular significance for drinking water utilities with low alkalinity source waters that are investigating AOPs, as there are limited published studies that have evaluated the treatment efficacy of five different oxidation processes in parallel.

  3. Recent Progress in Self‐Supported Metal Oxide Nanoarray Electrodes for Advanced Lithium‐Ion Batteries

    PubMed Central

    Zhang, Feng

    2016-01-01

    The rational design and fabrication of electrode materials with desirable architectures and optimized properties has been demonstrated to be an effective approach towards high‐performance lithium‐ion batteries (LIBs). Although nanostructured metal oxide electrodes with high specific capacity have been regarded as the most promising alternatives for replacing commercial electrodes in LIBs, their further developments are still faced with several challenges such as poor cycling stability and unsatisfying rate performance. As a new class of binder‐free electrodes for LIBs, self‐supported metal oxide nanoarray electrodes have many advantageous features in terms of high specific surface area, fast electron transport, improved charge transfer efficiency, and free space for alleviating volume expansion and preventing severe aggregation, holding great potential to solve the mentioned problems. This review highlights the recent progress in the utilization of self‐supported metal oxide nanoarrays grown on 2D planar and 3D porous substrates, such as 1D and 2D nanostructure arrays, hierarchical nanostructure arrays, and heterostructured nanoarrays, as anodes and cathodes for advanced LIBs. Furthermore, the potential applications of these binder‐free nanoarray electrodes for practical LIBs in full‐cell configuration are outlined. Finally, the future prospects of these self‐supported nanoarray electrodes are discussed.

  4. Toxicological and chemical assessment of arsenic-contaminated groundwater after electrochemical and advanced oxidation treatments.

    PubMed

    Radić, Sandra; Crnojević, Helena; Vujčić, Valerija; Gajski, Goran; Gerić, Marko; Cvetković, Želimira; Petra, Cvjetko; Garaj-Vrhovac, Vera; Oreščanin, Višnja

    2016-02-01

    Owing to its proven toxicity and mutagenicity, arsenic is regarded a principal pollutant in water used for drinking. The objective of this study was the toxicological and chemical evaluation of groundwater samples obtained from arsenic enriched drinking water wells before and after electrochemical and ozone-UV-H2O2-based advanced oxidation processes (EAOP). For this purpose, acute toxicity test with Daphnia magna and chronic toxicity test with Lemna minor L. were employed as well as in vitro bioassays using human peripheral blood lymphocytes (HPBLs). Several oxidative stress parameters were estimated in L.minor. Physicochemical analysis showed that EAOP treatment was highly efficient in arsenic but also in ammonia and organic compound removal from contaminated groundwater. Untreated groundwater caused only slight toxicity to HPBLs and D. magna in acute experiments. However, 7-day exposure of L. minor to raw groundwater elicited genotoxicity, a significant growth inhibition and oxidative stress injury. The observed genotoxicity and toxicity of raw groundwater samples was almost completely eliminated by EAOP treatment. Generally, the results obtained with L. minor were in agreement with those obtained in the chemical analysis suggesting the sensitivity of the model organism in monitoring of arsenic-contaminated groundwater. In parallel to chemical analysis, the implementation of chronic toxicity bioassays in a battery is recommended in the assessment of the toxic and genotoxic potential of such complex mixtures. PMID:26580737

  5. Advanced oxidation protein products and total antioxidant activity in colorectal carcinoma.

    PubMed

    Avinash, S S; Anitha, M; Vinodchandran; Rao, Gayathri M; Sudha, K; Shetty, Beena V

    2009-01-01

    The present study was designed to assess the levels of advanced oxidation protein products (AOPP) and percent hemolysis (that indirectly indicates the degree of membrane damage secondary to lipid peroxidation) in colorectal carcinoma. Glutathione (GSH), total thiols and albumin were measured to determine the antioxidant status. Considering the dynamic interaction between various antioxidants in the body, we measured the total antioxidant activity (AOA). Globulin was measured to assess the inflammatory response secondary to oxidative stress. Investigations were conducted in 45 cases of recently diagnosed primary colorectal adenocarcinoma. As control, 45 age and sex matched healthy persons were chosen. GSH was estimated in whole blood, percent hemolysis in RBC suspension and other parameters in plasma. We observed a very high significant increase (P<0.001) in AOPP, percent hemolysis and a highly significant increase (P<0.01) in globulin in colorectal carcinoma. We observed a very high significant decrease (P<0.001) in whole blood GSH, total thiols, albumin, AOA and a significant decrease (P<0.05) in plasma GSH in colorectal carcinoma. A very high significant negative correlation between percent hemolysis and AOA and an apparent negative correlation between total thiols and AOPP was seen in colorectal carcinoma. This demonstrated oxidative stress, decreased antioxidant status and secondary inflammatory response in colorectal carcinoma.

  6. Apparatus and method for stabilization or oxidation of polymeric materials

    DOEpatents

    Paulauskas, Felix L [Knoxville, TN; Sherman, Daniel M [Knoxville, TN

    2010-01-19

    An apparatus for treating polymeric materials comprises a treatment chamber adapted to maintain a selected atmosphere at a selected temperature; a means for supporting the polymeric material within the chamber; and, a source of ozone-containing gas, which decomposes at the selected temperature yielding at least one reactive oxidative species whereby the polymer is stabilized and cross linked through exposure to the oxidative species in the chamber at the selected temperature. The ozone may be generated by a plasma discharge or by various chemical processes. The apparatus may be configured for either batch-type or continuous-type processing. The apparatus and method are especially useful for preparing polymer fibers, particularly PAN fibers, for later carbonization treatments as well as to make flame-retardant fabrics.

  7. Method and apparatus for waste destruction using supercritical water oxidation

    DOEpatents

    Haroldsen, Brent Lowell; Wu, Benjamin Chiau-pin

    2000-01-01

    The invention relates to an improved apparatus and method for initiating and sustaining an oxidation reaction. A hazardous waste, is introduced into a reaction zone within a pressurized containment vessel. An oxidizer, preferably hydrogen peroxide, is mixed with a carrier fluid, preferably water, and the mixture is heated until the fluid achieves supercritical conditions of temperature and pressure. The heating means comprise cartridge heaters placed in closed-end tubes extending into the center region of the pressure vessel along the reactor longitudinal axis. A cooling jacket surrounds the pressure vessel to remove excess heat at the walls. Heating and cooling the fluid mixture in this manner creates a limited reaction zone near the center of the pressure vessel by establishing a steady state density gradient in the fluid mixture which gradually forces the fluid to circulate internally. This circulation allows the fluid mixture to oscillate between supercritical and subcritical states as it is heated and cooled.

  8. Apparatus and method for oxidation and stabilization of polymeric materials

    DOEpatents

    Paulauskas, Felix L [Knoxville, TN; White, Terry L [Knoxville, TN; Sherman, Daniel M [Knoxville, TN

    2009-05-19

    An apparatus for treating polymeric materials comprises a treatment chamber adapted to maintain a selected atmosphere; a means for supporting the polymeric material within the chamber; and, a source of plasma-derived gas containing at least one reactive oxidative species whereby the polymer is stabilized and cross linked through exposure to the oxidative species in the chamber at a selected temperature. The polymer may be directly exposed to the plasma, or alternatively, the plasma may be established in a separate volume from which the reactive species may be extracted and introduced into the vicinity of the polymer. The apparatus may be configured for either batch-type or continuous-type processing. The apparatus and method are especially useful for preparing polymer fibers, particularly PAN fibers, for later carbonization treatments.

  9. Apparatus and method for oxidation and stabilization of polymeric materials

    DOEpatents

    Paulauskas, Felix L [Knoxville, TN; White, Terry L [Knoxville, TN; Sherman, Daniel M [Knoxville, TN

    2010-08-31

    An apparatus for treating polymeric materials comprises a treatment chamber adapted to maintain a selected atmosphere; a means for supporting the polymeric material within the chamber; and, a source of plasma-derived gas containing at least one reactive oxidative species whereby the polymer is stabilized and cross linked through exposure to the oxidative species in the chamber at a selected temperature. The polymer may be directly exposed to the plasma, or alternatively, the plasma may be established in a separate volume from which the reactive species may be extracted and introduced into the vicinity of the polymer. The apparatus may be configured for either batch-type or continuous-type processing. The apparatus and method are especially useful for preparing polymer fibers, particularly PAN fibers, for later carbonization treatments.

  10. Manganese oxide nanowires, films, and membranes and methods of making

    DOEpatents

    Suib, Steven Lawrence; Yuan, Jikang

    2008-10-21

    Nanowires, films, and membranes comprising ordered porous manganese oxide-based octahedral molecular sieves, and methods of making, are disclosed. A single crystal ultra-long nanowire includes an ordered porous manganese oxide-based octahedral molecular sieve, and has an average length greater than about 10 micrometers and an average diameter of about 5 nanometers to about 100 nanometers. A film comprises a microporous network comprising a plurality of single crystal nanowires in the form of a layer, wherein a plurality of layers is stacked on a surface of a substrate, wherein the nanowires of each layer are substantially axially aligned. A free standing membrane comprises a microporous network comprising a plurality of single crystal nanowires in the form of a layer, wherein a plurality of layers is aggregately stacked, and wherein the nanowires of each layer are substantially axially aligned.

  11. Processing of alnico permanent magnets by advanced directional solidification methods

    DOE PAGES

    Zou, Min; Johnson, Francis; Zhang, Wanming; Zhao, Qi; Rutkowski, Stephen F.; Zhou, Lin; Kramer, Matthew J.

    2016-07-05

    Advanced directional solidification methods have been used to produce large (>15 cm length) castings of Alnico permanent magnets with highly oriented columnar microstructures. In combination with subsequent thermomagnetic and draw thermal treatment, this method was used to enable the high coercivity, high-Titanium Alnico composition of 39% Co, 29.5% Fe, 14% Ni, 7.5% Ti, 7% Al, 3% Cu (wt%) to have an intrinsic coercivity (Hci) of 2.0 kOe, a remanence (Br) of 10.2 kG, and an energy product (BH)max of 10.9 MGOe. These properties compare favorably to typical properties for the commercial Alnico 9. Directional solidification of higher Ti compositions yieldedmore » anisotropic columnar grained microstructures if high heat extraction rates through the mold surface of at least 200 kW/m2 were attained. This was achieved through the use of a thin walled (5 mm thick) high thermal conductivity SiC shell mold extracted from a molten Sn bath at a withdrawal rate of at least 200 mm/h. However, higher Ti compositions did not result in further increases in magnet performance. Images of the microstructures collected by scanning electron microscopy (SEM) reveal a majority α phase with inclusions of secondary αγ phase. Transmission electron microscopy (TEM) reveals that the α phase has a spinodally decomposed microstructure of FeCo-rich needles in a NiAl-rich matrix. In the 7.5% Ti composition the diameter distribution of the FeCo needles was bimodal with the majority having diameters of approximately 50 nm with a small fraction having diameters of approximately 10 nm. The needles formed a mosaic pattern and were elongated along one <001> crystal direction (parallel to the field used during magnetic annealing). Cu precipitates were observed between the needles. Regions of abnormal spinodal morphology appeared to correlate with secondary phase precipitates. The presence of these abnormalities did not prevent the material from displaying superior magnetic properties in the 7.5% Ti

  12. Processing of alnico permanent magnets by advanced directional solidification methods

    NASA Astrophysics Data System (ADS)

    Zou, Min; Johnson, Francis; Zhang, Wanming; Zhao, Qi; Rutkowski, Stephen F.; Zhou, Lin; Kramer, Matthew J.

    2016-12-01

    Advanced directional solidification methods have been used to produce large (>15 cm length) castings of Alnico permanent magnets with highly oriented columnar microstructures. In combination with subsequent thermomagnetic and draw thermal treatment, this method was used to enable the high coercivity, high-Titanium Alnico composition of 39% Co, 29.5% Fe, 14% Ni, 7.5% Ti, 7% Al, 3% Cu (wt%) to have an intrinsic coercivity (Hci) of 2.0 kOe, a remanence (Br) of 10.2 kG, and an energy product (BH)max of 10.9 MGOe. These properties compare favorably to typical properties for the commercial Alnico 9. Directional solidification of higher Ti compositions yielded anisotropic columnar grained microstructures if high heat extraction rates through the mold surface of at least 200 kW/m2 were attained. This was achieved through the use of a thin walled (5 mm thick) high thermal conductivity SiC shell mold extracted from a molten Sn bath at a withdrawal rate of at least 200 mm/h. However, higher Ti compositions did not result in further increases in magnet performance. Images of the microstructures collected by scanning electron microscopy (SEM) reveal a majority α phase with inclusions of secondary αγ phase. Transmission electron microscopy (TEM) reveals that the α phase has a spinodally decomposed microstructure of FeCo-rich needles in a NiAl-rich matrix. In the 7.5% Ti composition the diameter distribution of the FeCo needles was bimodal with the majority having diameters of approximately 50 nm with a small fraction having diameters of approximately 10 nm. The needles formed a mosaic pattern and were elongated along one <001> crystal direction (parallel to the field used during magnetic annealing). Cu precipitates were observed between the needles. Regions of abnormal spinodal morphology appeared to correlate with secondary phase precipitates. The presence of these abnormalities did not prevent the material from displaying superior magnetic properties in the 7.5% Ti

  13. An ultrasonic-accelerated oxidation method for determining the oxidative stability of biodiesel.

    PubMed

    Avila Orozco, Francisco D; Sousa, Antonio C; Domini, Claudia E; Ugulino Araujo, Mario Cesar; Fernández Band, Beatriz S

    2013-05-01

    Biodiesel is considered an alternative energy because it is produced from fats and vegetable oils by means of transesterification. Furthermore, it consists of fatty acid alkyl esters (FAAS) which have a great influence on biodiesel fuel properties and in the storage lifetime of biodiesel itself. The biodiesel storage stability is directly related to the oxidative stability parameter (Induction Time - IT) which is determined by means of the Rancimat® method. This method uses condutimetric monitoring and induces the degradation of FAAS by heating the sample at a constant temperature. The European Committee for Standardization established a standard (EN 14214) to determine the oxidative stability of biodiesel, which requires it to reach a minimum induction period of 6h as tested by Rancimat® method at 110°C. In this research, we aimed at developing a fast and simple alternative method to determine the induction time (IT) based on the FAAS ultrasonic-accelerated oxidation. The sonodegradation of biodiesel samples was induced by means of an ultrasonic homogenizer fitted with an immersible horn at 480Watts of power and 20 duty cycles. The UV-Vis spectrometry was used to monitor the FAAS sonodegradation by measuring the absorbance at 270nm every 2. Biodiesel samples from different feedstock were studied in this work. In all cases, IT was established as the inflection point of the absorbance versus time curve. The induction time values of all biodiesel samples determined using the proposed method was in accordance with those measured through the Rancimat® reference method by showing a R(2)=0.998.

  14. Thermal Properties of Oxides With Magnetoplumbite Structure for Advanced Thermal Barrier Coatings

    NASA Technical Reports Server (NTRS)

    Bansal, Narottam P.; Zhu, Dongming; Eslamloo-Grami, Maryam

    2007-01-01

    Oxides having magnetoplumbite structure are promising candidate materials for applications as high temperature thermal barrier coatings because of their high thermal stability, high thermal expansion, and low thermal conductivity. In this study, powders of LaMgAl11O19, GdMgAl11O19, SmMgAl11O19, and Gd0.7Yb0.3MgAl11O19 magnetoplumbite oxides were synthesized by citric acid sol-gel method and hot pressed into disk specimens. The thermal expansion coefficients (CTE) of these oxide materials were measured from room temperature to 1500 C. The average CTE value was found to be approx.9.6x10(exp -6)/C. Thermal conductivity of these magnetoplumbite-based oxide materials was also evaluated using steady-state laser heat flux test method. The effects of doping on thermal properties were also examined. Thermal conductivity of the doped Gd0.7Yb0.3MgAl11O19 composition was found to be lower than that of the undoped GdMgAl11O19. In contrast, thermal expansion coefficient was found to be independent of the oxide composition and appears to be controlled by the magnetoplumbite crystal structure. Thermal conductivity testing of LaMgAl11O19 and LaMnAl11O19 magnetoplumbite oxide coatings plasma sprayed on NiCrAlY/Rene N5 superalloy substrates indicated resistance of these coatings to sintering even at temperatures as high as 1600 C.

  15. Advanced TEM characterization of oxide nanoparticles in ODS Fe–12Cr–5Al alloys

    DOE PAGES

    Unocic, Kinga A.; Pint, Bruce A.; Hoelzer, David T.

    2016-07-11

    For oxide nanoparticles present in three oxide-dispersion-strengthened (ODS) Fe–12Cr–5Al alloys containing additions of (1) Y2O3 (125Y), (2) Y2O3 + ZrO2 (125YZ), and (3) Y2O3 + HfO2 (125YH), were investigated using transmission and scanning transmission electron microscopy. Furthermore, in all three alloys nano-sized (<3.5 nm) oxide particles distributed uniformly throughout the microstructure were characterized using advanced electron microscopy techniques. In the 125Y alloy, mainly Al2O3 and yttrium–aluminum garnet (YAG) phases (Y3Al5O12) were present, while in the 125YZ alloy, additional Zr(C,N) precipitates were identified. The 125YH alloy had the most complex precipitation sequence whereby in addition to the YAG and Al2O3 phases,more » Hf(C,N), Y2Hf2O7, and HfO2 precipitates were also found. The presence of HfO2 was mainly due to the incomplete incorporation of HfO2 powder during mechanical alloying of the 125YH alloy. The alloy having the highest total number density of the oxides, the smallest grain size, and the highest Vickers hardness was the 125YZ alloy indicating, that Y2O3 + ZrO2 additions had the strongest effect on grain size and tensile properties. Finally, high-temperature mechanical testing will be addressed in the near future, while irradiation studies are underway to investigate the irradiation resistance of these new ODS FeCrAl alloys.« less

  16. Sequential ozone advanced oxidation and biological oxidation processes to remove selected pharmaceutical contaminants from an urban wastewater.

    PubMed

    Espejo, Azahara; Aguinaco, Almudena; García-Araya, J F; Beltrán, Fernando J

    2014-01-01

    Sequential treatments consisting in a chemical process followed by a conventional biological treatment, have been applied to remove mixtures of nine contaminants of pharmaceutical type spiked in a primary sedimentation effluent of a municipal wastewater. Combinations of ozone, UVA black light (BL) and Fe(III) or Fe₃O₄ catalysts constituted the chemical systems. Regardless of the Advanced Oxidation Process (AOP), the removal of pharmaceutical compounds was achieved in 1 h of reaction, while total organic carbon (TOC) only diminished between 3.4 and 6%. Among selected ozonation systems to be implemented before the biological treatment, the application of ozone alone in the pre-treatment stage is recommended due to the increase of the biodegradability observed. The application of ozone followed by the conventional biological treatment leads high TOC and COD removal rates, 60 and 61%, respectively, and allows the subsequent biological treatment works with shorter hydraulic residence time (HRT). Moreover, the influence of the application of AOPs before and after a conventional biological process was compared, concluding that the decision to take depends on the characterization of the initial wastewater with pharmaceutical compounds.

  17. Incorporation of electrochemical advanced oxidation processes in a multistage treatment system for sanitary landfill leachate.

    PubMed

    Moreira, Francisca C; Soler, J; Fonseca, Amélia; Saraiva, Isabel; Boaventura, Rui A R; Brillas, Enric; Vilar, Vítor J P

    2015-09-15

    The current study has proved the technical feasibility of including electrochemical advanced oxidation processes (EAOPs) in a multistage strategy for the remediation of a sanitary landfill leachate that embraced: (i) first biological treatment to remove the biodegradable organic fraction, oxidize ammonium and reduce alkalinity, (ii) coagulation of the bio-treated leachate to precipitate humic acids and particles, followed by separation of the clarified effluent, and (iii) oxidation of the resulting effluent by an EAOP to degrade the recalcitrant organic matter and increase its biodegradability so that a second biological process for removal of biodegradable organics and nitrogen content could be applied. The influence of current density on an UVA photoelectro-Fenton (PEF) process was firstly assessed. The oxidation ability of various EAOPs such as electro-Fenton (EF) with two distinct initial total dissolved iron concentrations ([TDI]0), PEF and solar PEF (SPEF) was further evaluated and these processes were compared with their analogous chemical ones. A detailed assessment of the two first treatment stages was made and the biodegradability enhancement during the SPEF process was determined by a Zahn-Wellens test to define the ideal organics oxidation state to stop the EAOP and apply the second biological treatment. The best current density was 200 mA cm(-2) for a PEF process using a BDD anode, [TDI]0 of 60 mg L(-1), pH 2.8 and 20 °C. The relative oxidation ability of EAOPs increased in the order EF with 12 mg [TDI]0 L(-1) < EF with 60 mg [TDI]0 L(-1) < PEF with 60 mg [TDI]0 L(-1) ≤ SPEF with 60 mg [TDI]0 L(-1), using the abovementioned conditions. While EF process was much superior to the Fenton one, the superiority of PEF over photo-Fenton was less evident and SPEF attained similar degradation to solar photo-Fenton. To provide a final dissolved organic carbon (DOC) of 163 mg L(-1) to fulfill the discharge limits into the environment after

  18. Incorporation of electrochemical advanced oxidation processes in a multistage treatment system for sanitary landfill leachate.

    PubMed

    Moreira, Francisca C; Soler, J; Fonseca, Amélia; Saraiva, Isabel; Boaventura, Rui A R; Brillas, Enric; Vilar, Vítor J P

    2015-09-15

    The current study has proved the technical feasibility of including electrochemical advanced oxidation processes (EAOPs) in a multistage strategy for the remediation of a sanitary landfill leachate that embraced: (i) first biological treatment to remove the biodegradable organic fraction, oxidize ammonium and reduce alkalinity, (ii) coagulation of the bio-treated leachate to precipitate humic acids and particles, followed by separation of the clarified effluent, and (iii) oxidation of the resulting effluent by an EAOP to degrade the recalcitrant organic matter and increase its biodegradability so that a second biological process for removal of biodegradable organics and nitrogen content could be applied. The influence of current density on an UVA photoelectro-Fenton (PEF) process was firstly assessed. The oxidation ability of various EAOPs such as electro-Fenton (EF) with two distinct initial total dissolved iron concentrations ([TDI]0), PEF and solar PEF (SPEF) was further evaluated and these processes were compared with their analogous chemical ones. A detailed assessment of the two first treatment stages was made and the biodegradability enhancement during the SPEF process was determined by a Zahn-Wellens test to define the ideal organics oxidation state to stop the EAOP and apply the second biological treatment. The best current density was 200 mA cm(-2) for a PEF process using a BDD anode, [TDI]0 of 60 mg L(-1), pH 2.8 and 20 °C. The relative oxidation ability of EAOPs increased in the order EF with 12 mg [TDI]0 L(-1) < EF with 60 mg [TDI]0 L(-1) < PEF with 60 mg [TDI]0 L(-1) ≤ SPEF with 60 mg [TDI]0 L(-1), using the abovementioned conditions. While EF process was much superior to the Fenton one, the superiority of PEF over photo-Fenton was less evident and SPEF attained similar degradation to solar photo-Fenton. To provide a final dissolved organic carbon (DOC) of 163 mg L(-1) to fulfill the discharge limits into the environment after

  19. Performance of combined sodium persulfate/H2O2 based advanced oxidation process in stabilized landfill leachate treatment.

    PubMed

    Hilles, Ahmed H; Abu Amr, Salem S; Hussein, Rim A; El-Sebaie, Olfat D; Arafa, Anwaar I

    2016-01-15

    A combination of persulfate and hydrogen peroxide (S2O8(2-)/H2O2) was used to oxidizelandfill leachate. The reaction was performed under varying S2O8(2-)/H2O2 ratio (g/g), S2O8(2-)/H2O2 dosages (g/g), pH, and reaction time (minutes), so as to determine the optimum operational conditions. Results indicated that under optimum operational conditions (i.e. 120 min of oxidation using a S2O8(2-)/H2O2 ratio of 1 g/1.47 g at a persulfate and hydrogen peroxide dosage of 5.88 g/50 ml and8.63 g/50 ml respectively, at pH 11) removal of 81% COD and 83% NH3-N was achieved. In addition, the biodegradability (BOD5/COD ratio) of the leachate was improved from 0.09 to 0.17. The results obtained from the combined use of (S2O8(2-)/H2O2) were compared with those obtained with sodium persulfate only, hydrogen peroxide only and sodium persulfate followed by hydrogen peroxide. The combined method (S2O8(2-)/H2O2) achieved higher removal efficiencies for COD and NH3-N compared with the other methods using a single oxidizing agent. Additionally, the study has proved that the combination of S2O8(2-)/H2O2 is more efficient than the sequential use of sodium persulfate followed by hydrogen peroxide in advanced oxidation processes aiming at treatingstabilizedlandfill leachate.

  20. Amorphous mixed-metal hydroxide nanostructures for advanced water oxidation catalysts

    NASA Astrophysics Data System (ADS)

    Gao, Y. Q.; Liu, X. Y.; Yang, G. W.

    2016-02-01

    The design of highly efficient, durable, and earth-abundant catalysts for the oxygen evolution reaction (OER) is crucial in order to promote energy conversion and storage processes. Here, we synthesize amorphous mixed-metal (Ni-Fe) hydroxide nanostructures with a homogeneous distribution of Ni/Fe as well as a tunable Ni/Fe ratio by a simple, facile, green and low-cost electrochemical technique, and we demonstrate that the synthesized amorphous nanomaterials possess ultrahigh activity and super long-term cycle stability in the OER process. The amorphous Ni0.71Fe0.29(OH)x nanostructure affords a current density of 10 mA cm-2 at an overpotential of a mere 0.296 V and a small Tafel slope of 58 mV dec-1, while no deactivation is detected in the CV testing even up to 30 000 cycles, which suggests the promising application of these amorphous nanomaterials in electrochemical oxidation. Meanwhile, the distinct catalytic activities among these amorphous Ni-Fe hydroxide nanostructures prompts us to take notice of the composition of the alloy hydroxides/oxides when studying their catalytic properties, which opens an avenue for the rational design and controllable preparation of such amorphous nanomaterials as advanced OER electrocatalysts.The design of highly efficient, durable, and earth-abundant catalysts for the oxygen evolution reaction (OER) is crucial in order to promote energy conversion and storage processes. Here, we synthesize amorphous mixed-metal (Ni-Fe) hydroxide nanostructures with a homogeneous distribution of Ni/Fe as well as a tunable Ni/Fe ratio by a simple, facile, green and low-cost electrochemical technique, and we demonstrate that the synthesized amorphous nanomaterials possess ultrahigh activity and super long-term cycle stability in the OER process. The amorphous Ni0.71Fe0.29(OH)x nanostructure affords a current density of 10 mA cm-2 at an overpotential of a mere 0.296 V and a small Tafel slope of 58 mV dec-1, while no deactivation is detected in the CV

  1. Oxidation of glycosaminoglycans by free radicals and reactive oxidative species: A review of investigative methods.

    PubMed

    Parsons, B J

    2015-05-01

    Glycosaminoglycans, in particular hyaluronan (HA), and proteoglycans are components of the extracellular matrix (ECM). The ECM plays a key role in the regulation of cellular behaviour and alterations to it can modulate both the development of human diseases as well as controlling normal biochemical processes such as cell signalling and pro-inflammatory responses. For these reasons, in vitro fragmentation studies of glycosaminoglycans by free radicals and oxidative species are seen to be relevant to the understanding of in vivo studies of damage to the ECM. A wide range of investigative techniques have therefore been applied to gain insights into the relative fragmentation effects of several reactive oxidative species with the ultimate goal of determining mechanisms of fragmentation at the molecular level. These methods are reviewed here.

  2. A Method for Increasing Elders' Use of Advance Directives.

    ERIC Educational Resources Information Center

    Luptak, Marilyn K.; Boult, Chad

    1994-01-01

    Studied effectiveness of intervention to help frail elders to record advance directives (ADs). In collaboration with physicians and lay volunteer, social worker provided information/counseling to elderly subjects, families, and proxies in series of visits to geriatric evaluation and management clinic. Seventy-one percent of subjects recorded ADs.…

  3. Fabrication of advanced oxide fuels containing minor actinide for use in fast reactors

    SciTech Connect

    Miwa, Shuhei; Osaka, Masahiko; Tanaka, Kosuke; Ishi, Yohei; Yoshimochi, Hiroshi; Tanaka, Kenya

    2007-07-01

    R and D of advanced fuel containing minor actinide for use in fast reactors is described related to the composite fuel with MgO matrix. Fabrication tests of MgO composite fuels containing Am were done by a practical process that could be adapted to the presently used commercial manufacturing technology. Am-containing MgO composite fuels having good characteristics, i.e., having no defects, a high density, a homogeneous dispersion of host phase, were obtained. As related technology, burn-up characteristics of a fast reactor core loaded with the present MgO composite fuel were also analyzed, mainly in terms of core criticality. Furthermore, phase relations of MA oxide which was assumed to be contained in MgO matrix fuel were experimentally investigated. (authors)

  4. Depletion analysis of mixed-oxide fuel pins in light water reactors and the Advanced Test Reactor

    SciTech Connect

    Chang, G.S.; Ryskamp, J.M.

    2000-03-01

    An experiment containing weapons-grade mixed-oxide (WG-MOX) fuel has been designed and is being irradiated in the Advanced Test Reactor (ATR) at the Idaho National Engineering and Environmental Laboratory (INEEL). The ability to accurately predict fuel pin performance is an essential requirement for the MOX fuel test assembly design. Detailed radial fission power and temperature profile effects and fission gas release in the fuel pin are a function of the fuel pin's temperature, fission power, and fission product ad actinide concentration profiles. In addition, the burnup-dependent profile analyses in irradiated fuel pins is important for fuel performance analysis to support the potential licensing of the MOX fuel made from WG-plutonium and depleted uranium for use in US reactors. The MCNP Coupling With ORIGEN2 burnup calculation code (MCWO) can analyze the detailed burnup profiles of WG-MOX and reactor-grade mixed-oxide (RG-MOX) fuel pins. The validated code MCWO can provide the best-estimate neutronic characteristics of fuel burnup performance analysis. Applying this capability with a new minicell method allows calculation of detailed nuclide concentration and power distributions within the MOX pins as a function of burnup. This methodology was applied to MOX fuel in a commercial pressurized water reactor and in an experiment currently being irradiated in the ATR. The prediction of nuclide concentration profiles and power distributions in irradiated MOX plus via this new methodology can provide insights into MOX fuel performance.

  5. Analysis and advanced oxidation treatment of a persistent pharmaceutical compound in wastewater and wastewater sludge-carbamazepine.

    PubMed

    Mohapatra, D P; Brar, S K; Tyagi, R D; Picard, P; Surampalli, R Y

    2014-02-01

    Pharmaceutically active compounds (PhACs) are considered as emerging environmental problem due to their continuous input and persistence to the aquatic ecosystem even at low concentrations. Among them, carbamazepine (CBZ) has been detected at the highest frequency, which ends up in aquatic systems via wastewater treatment plants (WWTPs) among other sources. The identification and quantification of CBZ in wastewater (WW) and wastewater sludge (WWS) is of major interest to assess the toxicity of treated effluent discharged into the environment. Furthermore, WWS has been subjected for re-use either in agricultural application or for the production of value-added products through the route of bioconversion. However, this field application is disputable due to the presence of these organic compounds and in order to protect the ecosystem or end users, data concerning the concentration, fate, behavior as well as the perspective of simultaneous degradation of these compounds is urgently necessary. Many treatment technologies, including advanced oxidation processes (AOPs) have been developed in order to degrade CBZ in WW and WWS. AOPs are technologies based on the intermediacy of hydroxyl and other radicals to oxidize recalcitrant, toxic and non-biodegradable compounds to various by-products and eventually to inert end products. The purpose of this review is to provide information on persistent pharmaceutical compound, carbamazepine, its ecological effects and removal during various AOPs of WW and WWS. This review also reports the different analytical methods available for quantification of CBZ in different contaminated media including WW and WWS.

  6. Analysis and advanced oxidation treatment of a persistent pharmaceutical compound in wastewater and wastewater sludge-carbamazepine.

    PubMed

    Mohapatra, D P; Brar, S K; Tyagi, R D; Picard, P; Surampalli, R Y

    2014-02-01

    Pharmaceutically active compounds (PhACs) are considered as emerging environmental problem due to their continuous input and persistence to the aquatic ecosystem even at low concentrations. Among them, carbamazepine (CBZ) has been detected at the highest frequency, which ends up in aquatic systems via wastewater treatment plants (WWTPs) among other sources. The identification and quantification of CBZ in wastewater (WW) and wastewater sludge (WWS) is of major interest to assess the toxicity of treated effluent discharged into the environment. Furthermore, WWS has been subjected for re-use either in agricultural application or for the production of value-added products through the route of bioconversion. However, this field application is disputable due to the presence of these organic compounds and in order to protect the ecosystem or end users, data concerning the concentration, fate, behavior as well as the perspective of simultaneous degradation of these compounds is urgently necessary. Many treatment technologies, including advanced oxidation processes (AOPs) have been developed in order to degrade CBZ in WW and WWS. AOPs are technologies based on the intermediacy of hydroxyl and other radicals to oxidize recalcitrant, toxic and non-biodegradable compounds to various by-products and eventually to inert end products. The purpose of this review is to provide information on persistent pharmaceutical compound, carbamazepine, its ecological effects and removal during various AOPs of WW and WWS. This review also reports the different analytical methods available for quantification of CBZ in different contaminated media including WW and WWS. PMID:24140682

  7. Method for removing oxide contamination from silicon carbide powders

    DOEpatents

    Brynestad, J.; Bamberger, C.E.

    1984-08-01

    The described invention is directed to a method for removing oxide contamination in the form of oxygen-containing compounds such as SiO/sub 2/ and B/sub 2/O/sub 3/ from a charge of finely divided silicon carbide. The silicon carbide charge is contacted with a stream of hydrogen fluoride mixed with an inert gas carrier such as argon at a temperature in the range of about 200/sup 0/ to 650/sup 0/C. The oxides in the charge react with the heated hydrogen fluoride to form volatile gaseous fluorides such as SiF/sub 4/ and BF/sub 3/ which pass through the charge along with unreacted hydrogen fluoride and the carrier gas. Any residual gaseous reaction products and hydrogen fluoride remaining in the charge are removed by contacting the charge with the stream of inert gas which also cools the powder to room temperature. The removal of the oxygen contamination by practicing the present method provides silicon carbide powders with desirable pressing and sintering characteristics. 1 tab.

  8. Microwaves and their coupling to advanced oxidation processes: enhanced performance in pollutants degradation.

    PubMed

    Nascimento, Ulisses M; Azevedo, Eduardo B

    2013-01-01

    This review assesses microwaves (MW) coupled to advanced oxidation processes (AOPs) for pollutants degradation, as well as the basic theory and mechanisms of MW dielectric heating. We addressed the following couplings: MW/H2O2, MW/UV/H2O2, MW/Fenton, MW/US, and MW/UV/TiO2, as well as few studies that tested alternative oxidants and catalysts. Microwave Discharge Electrodeless Lamps (MDELs) are being extensively used with great advantages over ballasts. In their degradation studies, researchers generally employed domestic ovens with minor adaptations. Non-thermal effects and synergies between UV and MW radiation play an important role in the processes. Published papers so far report degradation enhancements between 30 and 1,300%. Unfortunately, how microwaves enhance pollutants is still obscure and real wastewaters scarcely studied. Based on the results surveyed in the literature, MW/AOPs are promising alternatives for treating/remediating environmental pollutants, whenever one considers high degradation yields, short reaction times, and small costs.

  9. Advanced tubular solid oxide fuel cells with high efficiency for internal reforming of hydrocarbon fuels

    NASA Astrophysics Data System (ADS)

    Cheekatamarla, Praveen K.; Finnerty, Caine M.; Du, Yanhai; Jiang, Juan; Dong, Jian; Dewald, P. G.; Robinson, C. R.

    Solid oxide fuel cells (SOFCs) constitute an attractive power-generation technology that converts chemical energy directly into electricity while causing little pollution. NanoDynamics Energy (NDE) Inc. has developed micro-tubular SOFC-based portable power generation systems that run on both gaseous and liquid fuels. In this paper, we present our next generation solid oxide fuel cells that exhibit total efficiencies in excess of 60% running on hydrogen fuel and 40+% running on readily available gaseous hydrocarbon fuels such as propane, butane etc. The advanced fuel cell design enables power generation at very high power densities and efficiencies (lower heating value-based) while reforming different hydrocarbon fuels directly inside the tubular SOFC without the aid of fuel pre-processing/reforming. The integrated catalytic layered SOFC demonstrated stable performance for >1000 h at high efficiency while running on propane fuel at sub-stoichiometric oxygen-to-fuel ratios. This technology will facilitate the introduction of highly efficient, reliable, fuel flexible, and lightweight portable power generation systems.

  10. Decolorization of kraft bleaching effluent by advanced oxidation processes using copper (II) as electron acceptor.

    PubMed

    Yeber, María C; Oñate, Katherine P; Vidal, Gladys

    2007-04-01

    Two advanced oxidation processes (AOPs), TiO2/UV/O2 and TiO2/UV/Cu (II), were used to remove color from a Kraft bleaching effluent. The optimal decoloration rate was determined by multivariate analysis, obtaining a mathematical model to evaluate the effect among variables. TiO2 and Cu (II) concentrations and the reaction times were optimized. The experimental design resulted in a quadratic matrix of 30 experiments. Additionally, the pH influence on the color removal was determined by multivariate analysis. Results indicate that color removal was 94% at acidic pH (3.0) in the presence of Cu (11) as an electron acceptor. Under this condition, the biodegradation of the effluent increased from 0.3 to 0.6. Moreover, 70% of COD (chemical oxygen demand) was removed, and the ecotoxicity, measured by Daphnia magna, was reduced. Photocatalytic oxidation to remove the color contained in the Kraft mill bleaching effluent was effective under the following conditions: short reaction time, acidic pH values, and without the addition of oxygen due to the presence of Cu (II) in the effluent. Moreover, residual Cu (II) was a minimum (0.05.mg L(-1)) and was not toxic to the next biological stage. The experimental design methodology indicated that a quadratic polynomial model may be used to representthe efficiencyfor degradation of the Kraft bleach pulp effluent by a photocatalytic process. PMID:17438808

  11. Unexpected toxicity to aquatic organisms of some aqueous bisphenol A samples treated by advanced oxidation processes.

    PubMed

    Tišler, Tatjana; Erjavec, Boštjan; Kaplan, Renata; Şenilă, Marin; Pintar, Albin

    2015-01-01

    In this study, photocatalytic and catalytic wet-air oxidation (CWAO) processes were used to examine removal efficiency of bisphenol A from aqueous samples over several titanate nanotube-based catalysts. Unexpected toxicity of bisphenol A (BPA) samples treated by means of the CWAO process to some tested species was determined. In addition, the CWAO effluent was recycled five- or 10-fold in order to increase the number of interactions between the liquid phase and catalyst. Consequently, the inductively coupled plasma mass spectrometry (ICP-MS) analysis indicated higher concentrations of some toxic metals like chromium, nickel, molybdenum, silver, and zinc in the recycled samples in comparison to both the single-pass sample and the photocatalytically treated solution. The highest toxicity of five- and 10-fold recycled solutions in the CWAO process was observed in water fleas, which could be correlated to high concentrations of chromium, nickel, and silver detected in tested samples. The obtained results clearly demonstrated that aqueous samples treated by means of advanced oxidation processes should always be analyzed using (i) chemical analyses to assess removal of BPA and total organic carbon from treated aqueous samples, as well as (ii) a battery of aquatic organisms from different taxonomic groups to determine possible toxicity. PMID:26114268

  12. Decolorization of kraft bleaching effluent by advanced oxidation processes using copper (II) as electron acceptor.

    PubMed

    Yeber, María C; Oñate, Katherine P; Vidal, Gladys

    2007-04-01

    Two advanced oxidation processes (AOPs), TiO2/UV/O2 and TiO2/UV/Cu (II), were used to remove color from a Kraft bleaching effluent. The optimal decoloration rate was determined by multivariate analysis, obtaining a mathematical model to evaluate the effect among variables. TiO2 and Cu (II) concentrations and the reaction times were optimized. The experimental design resulted in a quadratic matrix of 30 experiments. Additionally, the pH influence on the color removal was determined by multivariate analysis. Results indicate that color removal was 94% at acidic pH (3.0) in the presence of Cu (11) as an electron acceptor. Under this condition, the biodegradation of the effluent increased from 0.3 to 0.6. Moreover, 70% of COD (chemical oxygen demand) was removed, and the ecotoxicity, measured by Daphnia magna, was reduced. Photocatalytic oxidation to remove the color contained in the Kraft mill bleaching effluent was effective under the following conditions: short reaction time, acidic pH values, and without the addition of oxygen due to the presence of Cu (II) in the effluent. Moreover, residual Cu (II) was a minimum (0.05.mg L(-1)) and was not toxic to the next biological stage. The experimental design methodology indicated that a quadratic polynomial model may be used to representthe efficiencyfor degradation of the Kraft bleach pulp effluent by a photocatalytic process.

  13. Solar-Enhanced Advanced Oxidation Processes for Water Treatment: Simultaneous Removal of Pathogens and Chemical Pollutants.

    PubMed

    Tsydenova, Oyuna; Batoev, Valeriy; Batoeva, Agniya

    2015-08-14

    The review explores the feasibility of simultaneous removal of pathogens and chemical pollutants by solar-enhanced advanced oxidation processes (AOPs). The AOPs are based on in-situ generation of reactive oxygen species (ROS), most notably hydroxyl radicals •OH, that are capable of destroying both pollutant molecules and pathogen cells. The review presents evidence of simultaneous removal of pathogens and chemical pollutants by photocatalytic processes, namely TiO2 photocatalysis and photo-Fenton. Complex water matrices with high loads of pathogens and chemical pollutants negatively affect the efficiency of disinfection and pollutant removal. This is due to competition between chemical substances and pathogens for generated ROS. Other possible negative effects include light screening, competitive photon absorption, adsorption on the catalyst surface (thereby inhibiting its photocatalytic activity), etc. Besides, some matrix components may serve as nutrients for pathogens, thus hindering the disinfection process. Each type of water/wastewater would require a tailor-made approach and the variables that were shown to influence the processes-catalyst/oxidant concentrations, incident radiation flux, and pH-need to be adjusted in order to achieve the required degree of pollutant and pathogen removal. Overall, the solar-enhanced AOPs hold promise as an environmentally-friendly way to substitute or supplement conventional water/wastewater treatment, particularly in areas without access to centralized drinking water or sewage/wastewater treatment facilities.

  14. Amorphous mixed-metal hydroxide nanostructures for advanced water oxidation catalysts.

    PubMed

    Gao, Y Q; Liu, X Y; Yang, G W

    2016-03-01

    The design of highly efficient, durable, and earth-abundant catalysts for the oxygen evolution reaction (OER) is crucial in order to promote energy conversion and storage processes. Here, we synthesize amorphous mixed-metal (Ni-Fe) hydroxide nanostructures with a homogeneous distribution of Ni/Fe as well as a tunable Ni/Fe ratio by a simple, facile, green and low-cost electrochemical technique, and we demonstrate that the synthesized amorphous nanomaterials possess ultrahigh activity and super long-term cycle stability in the OER process. The amorphous Ni0.71Fe0.29(OH)x nanostructure affords a current density of 10 mA cm(-2) at an overpotential of a mere 0.296 V and a small Tafel slope of 58 mV dec(-1), while no deactivation is detected in the CV testing even up to 30 000 cycles, which suggests the promising application of these amorphous nanomaterials in electrochemical oxidation. Meanwhile, the distinct catalytic activities among these amorphous Ni-Fe hydroxide nanostructures prompts us to take notice of the composition of the alloy hydroxides/oxides when studying their catalytic properties, which opens an avenue for the rational design and controllable preparation of such amorphous nanomaterials as advanced OER electrocatalysts. PMID:26864279

  15. Solar-Enhanced Advanced Oxidation Processes for Water Treatment: Simultaneous Removal of Pathogens and Chemical Pollutants

    PubMed Central

    Tsydenova, Oyuna; Batoev, Valeriy; Batoeva, Agniya

    2015-01-01

    The review explores the feasibility of simultaneous removal of pathogens and chemical pollutants by solar-enhanced advanced oxidation processes (AOPs). The AOPs are based on in-situ generation of reactive oxygen species (ROS), most notably hydroxyl radicals •OH, that are capable of destroying both pollutant molecules and pathogen cells. The review presents evidence of simultaneous removal of pathogens and chemical pollutants by photocatalytic processes, namely TiO2 photocatalysis and photo-Fenton. Complex water matrices with high loads of pathogens and chemical pollutants negatively affect the efficiency of disinfection and pollutant removal. This is due to competition between chemical substances and pathogens for generated ROS. Other possible negative effects include light screening, competitive photon absorption, adsorption on the catalyst surface (thereby inhibiting its photocatalytic activity), etc. Besides, some matrix components may serve as nutrients for pathogens, thus hindering the disinfection process. Each type of water/wastewater would require a tailor-made approach and the variables that were shown to influence the processes—catalyst/oxidant concentrations, incident radiation flux, and pH—need to be adjusted in order to achieve the required degree of pollutant and pathogen removal. Overall, the solar-enhanced AOPs hold promise as an environmentally-friendly way to substitute or supplement conventional water/wastewater treatment, particularly in areas without access to centralized drinking water or sewage/wastewater treatment facilities. PMID:26287222

  16. Removal of pharmaceutical and personal care products from reverse osmosis retentate using advanced oxidation processes.

    PubMed

    Abdelmelek, Sihem Ben; Greaves, John; Ishida, Kenneth P; Cooper, William J; Song, Weihua

    2011-04-15

    The application of reverse osmosis (RO) in water intended for reuse is promising for assuring high water quality. However, one significant disadvantage is the need to dispose of the RO retentate (or reject water). Studies focusing on Pharmaceutical and Personal Care Products (PPCPs) have raised questions concerning their concentrations in the RO retentate. Advanced oxidation processes (AOPs) are alternatives for destroying these compounds in retentate that contains high concentration of effluent organic matter (EfOM) and other inorganic constituents. Twenty-seven PPCPs were screened in a RO retentate using solid phase extraction (SPE) and UPLC-MS/MS, and detailed degradation studies for 14 of the compounds were obtained. Based on the absolute hydroxyl radical (HO•) reaction rate constants for individual pharmaceutical compounds, and that of the RO retentate (EfOM and inorganic constituents), it was possible to model their destruction. Using excitation-emission matrix (EEM) fluorescence spectroscopy, the HO• oxidation of the EfOM could be observed through decreases in the retentate fluorescence. The decrease in the peak normally associated with proteins correlated well with the removal of the pharmaceutical compounds. These results suggest that fluorescence may be a suitable parameter for monitoring the degradation of PPCPs by AOPs in RO retentates. PMID:21384915

  17. Advanced oxidation degradation kinetics as a function of ultraviolet LED duty cycle.

    PubMed

    Duckworth, Kelsey; Spencer, Michael; Bates, Christopher; Miller, Michael E; Almquist, Catherine; Grimaila, Michael; Magnuson, Matthew; Willison, Stuart; Phillips, Rebecca; Racz, LeeAnn

    2015-01-01

    Ultraviolet (UV) light emitting diodes (LEDs) may be a viable option as a UV light source for advanced oxidation processes (AOPs) utilizing photocatalysts or oxidizing agents such as hydrogen peroxide. The effect of UV-LED duty cycle, expressed as the percentage of time the LED is powered, was investigated in an AOP with hydrogen peroxide, using methylene blue (MB) to assess contaminant degradation. The UV-LED AOP degraded the MB at all duty cycles. However, adsorption of MB onto the LED emitting surface caused a linear decline in reactor performance over time. With regard to the effect of duty cycle, the observed rate constant of MB degradation, after being adjusted to account for the duty cycle, was greater for 5 and 10% duty cycles than higher duty cycles, providing a value approximately 160% higher at 5% duty cycle than continuous operation. This increase in adjusted rate constant at low duty cycles, as well as contaminant fouling of the LED surface, may impact design and operational considerations for pulsed UV-LED AOP systems. PMID:25945855

  18. Comparison of advanced distillation control methods. First annual report

    SciTech Connect

    1996-11-01

    A detailed dynamic simulator of a propylene/propane (C3) splitter, which was bench-marked against industrial data, has been used to compare dual composition control performance for a diagonal PI controller and several advanced controllers. The advanced controllers considered are DMC, nonlinear process model based control, and articial neutral networks. Each controller was tuned based upon setpoint changes in the overhead product composition using 50% changes in the impurity levels. Overall, there was not a great deal of difference in controller performance based upon the setpoint and disturbance tests. Periodic step changes in feed composition were also used to compare controller performance. In this case, oscillatory variations of the product composition were observed and the variabilities of the DMC and nonlinear process model based controllers were substantially smaller than that of the PI controller. The sensitivity of each controller to the frequency of the periodic step changes in feed composition was also investigated.

  19. Comparison of advanced distillation control methods. First annual report

    SciTech Connect

    Riggs, J.B.

    1996-11-01

    A detailed dynamic simulator of a propylene/propane (C{sub 3}) splitter, which was bench-marked against industrial data, has been used to compare dual composition control performance for a diagonal PI controller and several advanced controllers. The advanced controllers considered are dynamic matrix control (DMC), nonlinear process model based control, and artificial neutral networks. Each controller was tuned based upon setpoint changes in the overhead product composition using 50% changes in the impurity levels. Overall, there was not a great deal of difference in controller performance based upon the setpoint and disturbance tests. Periodic step changes in feed composition were also used to compare controller performance. In this case, oscillatory variations of the product composition were observed and the variabilities of the DC and nonlinear process model based controllers were substantially smaller than that of the PI controller. The sensitivity of each controller to the frequency of the periodic step changes in feed composition was also investigated.

  20. Conceptual frameworks and methods for advancing invasion ecology.

    PubMed

    Heger, Tina; Pahl, Anna T; Botta-Dukát, Zoltan; Gherardi, Francesca; Hoppe, Christina; Hoste, Ivan; Jax, Kurt; Lindström, Leena; Boets, Pieter; Haider, Sylvia; Kollmann, Johannes; Wittmann, Meike J; Jeschke, Jonathan M

    2013-09-01

    Invasion ecology has much advanced since its early beginnings. Nevertheless, explanation, prediction, and management of biological invasions remain difficult. We argue that progress in invasion research can be accelerated by, first, pointing out difficulties this field is currently facing and, second, looking for measures to overcome them. We see basic and applied research in invasion ecology confronted with difficulties arising from (A) societal issues, e.g., disparate perceptions of invasive species; (B) the peculiarity of the invasion process, e.g., its complexity and context dependency; and (C) the scientific methodology, e.g., imprecise hypotheses. To overcome these difficulties, we propose three key measures: (1) a checklist for definitions to encourage explicit definitions; (2) implementation of a hierarchy of hypotheses (HoH), where general hypotheses branch into specific and precisely testable hypotheses; and (3) platforms for improved communication. These measures may significantly increase conceptual clarity and enhance communication, thus advancing invasion ecology.

  1. Exploring biomolecular dynamics and interactions using advanced sampling methods

    NASA Astrophysics Data System (ADS)

    Luitz, Manuel; Bomblies, Rainer; Ostermeir, Katja; Zacharias, Martin

    2015-08-01

    Molecular dynamics (MD) and Monte Carlo (MC) simulations have emerged as a valuable tool to investigate statistical mechanics and kinetics of biomolecules and synthetic soft matter materials. However, major limitations for routine applications are due to the accuracy of the molecular mechanics force field and due to the maximum simulation time that can be achieved in current simulations studies. For improving the sampling a number of advanced sampling approaches have been designed in recent years. In particular, variants of the parallel tempering replica-exchange methodology are widely used in many simulation studies. Recent methodological advancements and a discussion of specific aims and advantages are given. This includes improved free energy simulation approaches and conformational search applications.

  2. Effects of Doping on Thermal Conductivity of Pyrochlore Oxides for Advanced Thermal Barrier Coatings

    NASA Technical Reports Server (NTRS)

    Bansal, Narottam P.; Zhu, Dongming; Eslamloo-Grami, Maryam

    2006-01-01

    Pyrochlore oxides of general composition, A2B2O7, where A is a 3(+) cation (La to Lu) and B is a 4(+) cation (Zr, Hf, Ti, etc.) have high melting point, relatively high coefficient of thermal expansion, and low thermal conductivity which make them suitable for applications as high-temperature thermal barrier coatings. The effect of doping at the A site on the thermal conductivity of a pyrochlore oxide La2Zr2O7, has been investigated. Oxide powders of various compositions La2Zr2O7, La(1.7)Gd(0.3)Zr2O7, La(1.7)Yb(0.3)Zr2O7 and La(1.7)Gd(0.15)Yb(0.15)Zr2O7 were synthesized by the citric acid sol-gel method. These powders were hot pressed into discs and used for thermal conductivity measurements using a steady-state laser heat flux test technique. The rare earth oxide doped pyrochlores La(1.7)Gd(0.3)Zr2O7, La(1.7)Yb(0.3)Zr2O7 and La(1.7)Gd(0.15)Yb(0.15)Zr2O7 had lower thermal conductivity than the un-doped La2Zr2O7. The Gd2O3 and Yb2O3 co-doped composition showed the lowest thermal conductivity.

  3. Recent Advances in Superparamagnetic Iron Oxide Nanoparticles for Cellular Imaging and Targeted Therapy Research

    PubMed Central

    Wang, Yi-Xiang J.; Xuan, Shouhu; Port, Marc; Idee, Jean-Marc

    2013-01-01

    Advances of nanotechnology have led to the development of nanomaterials with both potential diagnostic and therapeutic applications. Among them, superparamagnetic iron oxide (SPIO) nanoparticles have received particular attention. Over the past decade, various SPIOs with unique physicochemical and biological properties have been designed by modifying the particle structure, size and coating. This article reviews the recent advances in preparing SPIOs with novel properties, the way these physicochemical properties of SPIOs influence their interaction with cells, and the development of SPIOs in liver and lymph nodes magnetic resonance imaging (MRI) contrast. Cellular uptake of SPIO can be exploited in a variety of potential clinical applications, including stem cell and inflammation cell tracking and intra-cellular drug delivery to cancerous cells which offers higher intra-cellular concentration. When SPIOs are used as carrier vehicle, additional advantages can be achieved including magnetic targeting and hyperthermia options, as well as monitoring with MRI. Other potential applications of SPIO include magnetofection and gene delivery, targeted retention of labeled stem cells, sentinel lymph nodes mapping, and magnetic force targeting and cell orientation for tissue engineering. PMID:23621536

  4. Thermoelectric material including conformal oxide layers and method of making the same using atomic layer deposition

    DOEpatents

    Cho, Jung Young; Ahn, Dongjoon; Salvador, James R.; Meisner, Gregory P.

    2016-06-07

    A thermoelectric material includes a substrate particle and a plurality of conformal oxide layers formed on the substrate particle. The plurality of conformal oxide layers has a total oxide layer thickness ranging from about 2 nm to about 20 nm. The thermoelectric material excludes oxide nanoparticles. A method of making the thermoelectric material is also disclosed herein.

  5. Insights into real cotton-textile dyeing wastewater treatment using solar advanced oxidation processes.

    PubMed

    Soares, Petrick A; Silva, Tânia F C V; Manenti, Diego R; Souza, Selene M A G U; Boaventura, Rui A R; Vilar, Vítor J P

    2014-01-01

    Different advanced oxidation processes (AOPs) were applied to the treatment of a real cotton-textile dyeing wastewater as a pre-oxidation step to enhance the biodegradability of the recalcitrant compounds, which can be further oxidized using a biological process. Tests were conducted on a lab-scale prototype using artificial solar radiation and at pilot scale with compound parabolic collectors using natural solar radiation. The cotton-textile dyeing wastewater presents a lilac color, with a maximum absorbance peak at 641 nm, alkaline pH (pH = 8.2), moderate organic content (DOC = 152 mg C L(-1), COD = 684 mg O2 L(-1)) and low-moderate biodegradability (40 % after 28 days in Zahn-Wellens test). All the tested processes contributed to an effective decolorization and mineralization, but the most efficient process was the solar-photo-Fenton with an optimum catalyst concentration of 60 mg Fe(2+) L(-1), leading to 98.5% decolorization and 85.5% mineralization after less than 0.1 and 5.8 kJUV L(-1), respectively. In order to achieve a final wastewater with a COD below 250 mg O2 L(-1) (discharge limit into water bodies imposed by the Portuguese Legislation-Portaria no. 423/97 of 25 June 1997), considering the combination of a solar-photo-Fenton reaction with a biological process, the phototreatment energy required is 0.5 kJUV L(-1), consuming 7.5 mM hydrogen peroxide, resulting in 58.4% of mineralization [Formula: see text].

  6. Insights into real cotton-textile dyeing wastewater treatment using solar advanced oxidation processes.

    PubMed

    Soares, Petrick A; Silva, Tânia F C V; Manenti, Diego R; Souza, Selene M A G U; Boaventura, Rui A R; Vilar, Vítor J P

    2014-01-01

    Different advanced oxidation processes (AOPs) were applied to the treatment of a real cotton-textile dyeing wastewater as a pre-oxidation step to enhance the biodegradability of the recalcitrant compounds, which can be further oxidized using a biological process. Tests were conducted on a lab-scale prototype using artificial solar radiation and at pilot scale with compound parabolic collectors using natural solar radiation. The cotton-textile dyeing wastewater presents a lilac color, with a maximum absorbance peak at 641 nm, alkaline pH (pH = 8.2), moderate organic content (DOC = 152 mg C L(-1), COD = 684 mg O2 L(-1)) and low-moderate biodegradability (40 % after 28 days in Zahn-Wellens test). All the tested processes contributed to an effective decolorization and mineralization, but the most efficient process was the solar-photo-Fenton with an optimum catalyst concentration of 60 mg Fe(2+) L(-1), leading to 98.5% decolorization and 85.5% mineralization after less than 0.1 and 5.8 kJUV L(-1), respectively. In order to achieve a final wastewater with a COD below 250 mg O2 L(-1) (discharge limit into water bodies imposed by the Portuguese Legislation-Portaria no. 423/97 of 25 June 1997), considering the combination of a solar-photo-Fenton reaction with a biological process, the phototreatment energy required is 0.5 kJUV L(-1), consuming 7.5 mM hydrogen peroxide, resulting in 58.4% of mineralization [Formula: see text]. PMID:23832802

  7. Methods and Applications for Advancing Distance Education Technologies: International Issues and Solutions

    ERIC Educational Resources Information Center

    Syed, Mahbubur Rahman, Ed.

    2009-01-01

    The emerging field of advanced distance education delivers academic courses across time and distance, allowing educators and students to participate in a convenient learning method. "Methods and Applications for Advancing Distance Education Technologies: International Issues and Solutions" demonstrates communication technologies, intelligent…

  8. Manufacture and engine test of advanced oxide dispersion strengthened alloy turbine vanes. [for space shuttle thermal protection

    NASA Technical Reports Server (NTRS)

    Bailey, P. G.

    1977-01-01

    Oxide-Dispersion-strengthened (ODS) Ni-Cr-Al alloy systems were exploited for turbine engine vanes which would be used for the space shuttle thermal protection system. Available commercial and developmental advanced ODS alloys were evaluated, and three were selected based on established vane property goals and manufacturing criteria. The selected alloys were evaluated in an engine test. Candidate alloys were screened by strength, thermal fatigue resistance, oxidation and sulfidation resistance. The Ni-16Cr (3 to 5)Al-ThO2 system was identified as having attractive high temperature oxidation resistance. Subsequent work also indicated exceptional sulfidation resistance for these alloys.

  9. Advanced Extraction Methods for Actinide/Lanthanide Separations

    SciTech Connect

    Scott, M.J.

    2005-12-01

    The separation of An(III) ions from chemically similar Ln(III) ions is perhaps one of the most difficult problems encountered during the processing of nuclear waste. In the 3+ oxidation states, the metal ions have an identical charge and roughly the same ionic radius. They differ strictly in the relative energies of their f- and d-orbitals, and to separate these metal ions, ligands will need to be developed that take advantage of this small but important distinction. The extraction of uranium and plutonium from nitric acid solution can be performed quantitatively by the extraction with the TBP (tributyl phosphate). Commercially, this process has found wide use in the PUREX (plutonium uranium extraction) reprocessing method. The TRUEX (transuranium extraction) process is further used to coextract the trivalent lanthanides and actinides ions from HLLW generated during PUREX extraction. This method uses CMPO [(N, N-diisobutylcarbamoylmethyl) octylphenylphosphineoxide] intermixed with TBP as a synergistic agent. However, the final separation of trivalent actinides from trivalent lanthanides still remains a challenging task. In TRUEX nitric acid solution, the Am(III) ion is coordinated by three CMPO molecules and three nitrate anions. Taking inspiration from this data and previous work with calix[4]arene systems, researchers on this project have developed a C3-symmetric tris-CMPO ligand system using a triphenoxymethane platform as a base. The triphenoxymethane ligand systems have many advantages for the preparation of complex ligand systems. The compounds are very easy to prepare. The steric and solubility properties can be tuned through an extreme range by the inclusion of different alkoxy and alkyl groups such as methyoxy, ethoxy, t-butoxy, methyl, octyl, t-pentyl, or even t-pentyl at the ortho- and para-positions of the aryl rings. The triphenoxymethane ligand system shows promise as an improved extractant for both tetravalent and trivalent actinide recoveries form

  10. Mineralization of salicylic acid in acidic aqueous medium by electrochemical advanced oxidation processes using platinum and boron-doped diamond as anode and cathodically generated hydrogen peroxide.

    PubMed

    Guinea, Elena; Arias, Conchita; Cabot, Pere Lluís; Garrido, José Antonio; Rodríguez, Rosa María; Centellas, Francesc; Brillas, Enric

    2008-01-01

    Solutions containing 164 mg L(-1) salicylic acid of pH 3.0 have been degraded by electrochemical advanced oxidation processes such as anodic oxidation, anodic oxidation with electrogenerated H(2)O(2), electro-Fenton, photoelectro-Fenton and solar photoelectro-Fenton at constant current density. Their oxidation power has been comparatively studied in a one-compartment cell with a Pt or boron-doped diamond (BDD) anode and a graphite or O(2)-diffusion cathode. In the three latter procedures, 0.5mM Fe(2+) is added to the solution to form hydroxyl radical (()OH) from Fenton's reaction between Fe(2+) and H(2)O(2) generated at the O(2)-diffusion cathode. Total mineralization is attained for all methods with BDD and for photoelectro-Fenton and solar photoelectro-Fenton with Pt. The poor decontamination achieved in anodic oxidation and electro-Fenton with Pt is explained by the slow removal of most pollutants by ()OH formed from water oxidation at the Pt anode in comparison to their quick destruction with ()OH produced at BDD. ()OH generated from Fenton's reaction oxidizes rapidly all aromatic pollutants, but it cannot destroy final Fe(III)-oxalate complexes. Solar photoelectro-Fenton treatments always yield quicker degradation rate due to the very fast photodecarboxylation of these complexes by UVA irradiation supplied by solar light. The effect of current density on the degradation rate, efficiency and energy cost of all methods is examined. The salicylic acid decay always follows a pseudo-first-order kinetics. 2,3-Dihydroxybenzoic, 2,5-dihydroxybenzoic, 2,6-dihydroxybenzoic, alpha-ketoglutaric, glycolic, glyoxylic, maleic, fumaric, malic, tartronic and oxalic acids are detected as oxidation products. A general reaction sequence for salicylic acid mineralization considering all these intermediates is proposed.

  11. Advanced 3D inverse method for designing turbomachine blades

    SciTech Connect

    Dang, T.

    1995-10-01

    To meet the goal of 60% plant-cycle efficiency or better set in the ATS Program for baseload utility scale power generation, several critical technologies need to be developed. One such need is the improvement of component efficiencies. This work addresses the issue of improving the performance of turbo-machine components in gas turbines through the development of an advanced three-dimensional and viscous blade design system. This technology is needed to replace some elements in current design systems that are based on outdated technology.

  12. A method for increasing elders' use of advance directives.

    PubMed

    Luptak, M K; Boult, C

    1994-06-01

    Most published studies report that few elderly people have recorded advance directives (AD). We studied the effectiveness of an interdisciplinary intervention designed to help ambulatory frail elders to record AD. In collaboration with physicians and a trained lay volunteer, a social worker provided information and counseling to the elderly subjects, to their families, and to their proxies in a series of visits to a geriatric evaluation and management (GEM) clinic. Seventy-one percent of the subjects recorded AD. Of these, 96% named a proxy, and 83% recorded specific treatment preferences.

  13. Method to measure ethylene oxide/propylene oxide surfactants in resist developers

    NASA Astrophysics Data System (ADS)

    Holt, Rodica; Oberlander, Joseph E.; Calindas, Maria Fides Y.; Gonzalez, Eleazar; Ranque, Pilarcita L.

    1998-06-01

    Controlling the exact level of surfactants in resist developers is critical. Surfactant concentrations can influence parameters such as photospeed, resolution, and linearity. Too much or too little surfactant can have a significant impact on the performance of the developer. In our laboratory an analytical procedure was developed to quantitate an Ethylene Oxide/Propylene Oxide (EO/PO) surfactant in an aqueous Tetra Alkyl Ammonium Hydroxide developer. The procedure takes advantage of the chemical property of the EO/PO surfactant to complex with aqueous cobalt thiocyanate solution to form a blue cobalt containing dye. The coupled dye is soluble in methylene chloride and visible at lambda 620 nm. The amount of dye formation is directly proportional to the amount of EO/PO surfactant present in the sample, over an established range. The analytical method provides precise and accurate quantitation of the EO/PO surfactant in the resist developers. It is relatively easy to perform and enables the user to qualify a resist developer with respect to its surfactant content. Also, the method developed is sufficiently general and can be applied to other types of nonionic surfactants presented in resist developers.

  14. ADVANCED OXIDATION PROCESSES (AOPS) FOR DESTRUCTION OF METHYL TERTIARY BUTYL ETHER (MTBE -AN UNREGULATED CONTAMINANT) IN DRINKING WATER

    EPA Science Inventory

    Advanced oxidation processes (AOPs) provide a promising treatment option for the destruction of MTBE directly in surface and ground waters. An ongoing study is evaluating the ability of three AOPs; hydrogen peroxide/ozone (H2O2/ O3), ultraviolet irradiation/ozone (UV/O3) and ultr...

  15. Effect Of Inorganic, Synthetic And Naturally Occurring Chelating Agents On Fe(II) Mediated Advanced Oxidation Of Chlorophenols

    EPA Science Inventory

    This study examines the feasibility and application of Advanced Oxidation Technologies (AOTs) for the treatment of chlorophenols that are included in US EPA priority pollutant list. A novel class of sulfate/hydroxyl radical-based homogeneous AOTs (Fe(II)/PS, Fe(II)/PMS, Fe(II)/H...

  16. Investigation of the oxidative ammonolysis of propylene on oxide catalysts containing molybdenum and using the response method

    SciTech Connect

    Gadzhiev, K.N.; Adzhamov, K.Y.; Alkhazov, T.G.; Khanmamedova, A.K.

    1985-07-01

    The response method has been used to study the oxidative ammonolysis of propylene on MoO/sub 3/ and molybdenum oxide systems containing bismuth, silicon, and phosphorous ions. The response curves obtained for ammonia, propylene, CO/sub 2/, acrolein, acrylonitrile in these systems are discussed and compared with individual molybdenum trioxide. It has been shown that the modifying action of ammonia on the catalyst surfaces determines the direction of the oxidative conversion of the propylene.

  17. Method of forming oxide coatings. [for solar collector heating panels

    NASA Technical Reports Server (NTRS)

    Mcdonald, G. E. (Inventor)

    1983-01-01

    This invention is concerned with an improved plating process for covering a substrate with a black metal oxide film. The invention is particularly directed to making a heating panel for a solar collector. A compound is electrodeposited from an aqueous solution containing cobalt metal salts onto a metal substrate. This compound is converted during plating into a black, highly absorbing oxide coating which contains hydrated oxides. This is achieved by the inclusion of an oxidizing agent in the plating bath. The inclusion of an oxidizing agent in the plating bath is contrary to standard electroplating practice. The hydrated oxides are converted to oxides by treatment in a hot bath, such as boiling water. An oxidizing agent may be added to the hot liquid treating bath.

  18. Method for predicting photocatalytic oxidation rates of organic compounds.

    PubMed

    Sattler, Melanie L; Liljestrand, Howard M

    2003-01-01

    In designing a photocatalytic oxidation (PCO) system for a given air pollution source, destruction rates for volatile organic compounds (VOCs) are required. The objective of this research was to develop a systematic method of predicting PCO rate constants by correlating rate constants with physical-chemical characteristics of compounds. Accordingly, reaction rate constants were determined for destruction of volatile organics over a titanium dioxide (TiO2) catalyst in a continuous mixed-batch reactor. It was found that PCO rate constants for alkanes and alkenes vary linearly with gas-phase ionization potential (IP) and with gas-phase hydroxyl radical reaction rate constant. The correlations allow rates of destruction of compounds not tested in this research to be predicted based on physical-chemical characteristics. PMID:12568248

  19. Method for reducing nitrogen oxides in combustion effluents

    DOEpatents

    Zauderer, Bert

    2000-01-01

    Method for reducing nitrogen oxides (NO.sub.x) in the gas stream from the combustion of fossil fuels is disclosed. In a narrow gas temperature zone, NO.sub.x is converted to nitrogen by reaction with urea or ammonia with negligible remaining ammonia and other reaction pollutants. Specially designed injectors are used to introduce air atomized water droplets containing dissolved urea or ammonia into the gaseous combustion products in a manner that widely disperses the droplets exclusively in the optimum reaction temperature zone. The injector operates in a manner that forms droplet of a size that results in their vaporization exclusively in this optimum NO.sub.x -urea/ammonia reaction temperature zone. Also disclosed is a design of a system to effectively accomplish this injection.

  20. Indium oxide inverse opal films synthesized by structure replication method

    NASA Astrophysics Data System (ADS)

    Amrehn, Sabrina; Berghoff, Daniel; Nikitin, Andreas; Reichelt, Matthias; Wu, Xia; Meier, Torsten; Wagner, Thorsten

    2016-04-01

    We present the synthesis of indium oxide (In2O3) inverse opal films with photonic stop bands in the visible range by a structure replication method. Artificial opal films made of poly(methyl methacrylate) (PMMA) spheres are utilized as template. The opal films are deposited via sedimentation facilitated by ultrasonication, and then impregnated by indium nitrate solution, which is thermally converted to In2O3 after drying. The quality of the resulting inverse opal film depends on many parameters; in this study the water content of the indium nitrate/PMMA composite after drying is investigated. Comparison of the reflectance spectra recorded by vis-spectroscopy with simulated data shows a good agreement between the peak position and calculated stop band positions for the inverse opals. This synthesis is less complex and highly efficient compared to most other techniques and is suitable for use in many applications.

  1. Method for combined removal of mercury and nitrogen oxides from off-gas streams

    DOEpatents

    Mendelsohn, Marshall H.; Livengood, C. David

    2006-10-10

    A method for removing elemental Hg and nitric oxide simultaneously from a gas stream is provided whereby the gas stream is reacted with gaseous chlorinated compound to convert the elemental mercury to soluble mercury compounds and the nitric oxide to nitrogen dioxide. The method works to remove either mercury or nitrogen oxide in the absence or presence of each other.

  2. Method for improving catalyst function in auto-thermal and partial oxidation reformer-based processors

    DOEpatents

    Ahmed, Shabbir; Papadias, Dionissios D.; Lee, Sheldon H.D.; Ahluwalia, Rajesh K.

    2014-08-26

    The invention provides a method for reforming fuel, the method comprising contacting the fuel to an oxidation catalyst so as to partially oxidize the fuel and generate heat; warming incoming fuel with the heat while simultaneously warming a reforming catalyst with the heat; and reacting the partially oxidized fuel with steam using the reforming catalyst.

  3. Method for forming H2-permselective oxide membranes

    DOEpatents

    Gavalas, George R.; Nam, Suk Woo; Tsapatsis, Michael; Kim, Soojin

    1995-01-01

    Methods of forming permselective oxide membranes that are highly selective to permeation of hydrogen by chemical deposition of reactants in the pore of porous tubes, such as Vycor.TM. glass or Al.sub.2 O.sub.3 tubes. The porous tubes have pores extending through the tube wall. The process involves forming a stream containing a first reactant of the formula RX.sub.n, wherein R is silicon, titanium, boron or aluminum, X is chlorine, bromine or iodine, and n is a number which is equal to the valence of R; and forming another stream containing water vapor as the second reactant. Both of the reactant streams are passed along either the outside or the inside surface of a porous tube and the streams react in the pores of the porous tube to form a nonporous layer of R-oxide in the pores. The membranes are formed by the hydrolysis of the respective halides. In another embodiment, the first reactant stream contains a first reactant having the formula SiH.sub.n Cl.sub.4-n where n is 1, 2 or 3; and the second reactant stream contains water vapor and oxygen. In still another embodiment the first reactant stream containing a first reactant selected from the group consisting of Cl.sub.3 SiOSiCl.sub.3, Cl.sub.3 SiOSiCl.sub.2 OSiCl.sub.3, and mixtures thereof and the second reactant stream contains water vapor. In still another embodiment, membrane formation is carried out by an alternating flow deposition method. This involves a sequence of cycles, each cycle comprising introduction of the halide-containing stream and allowance of a specific time for reaction followed by purge and flow of the water vapor containing stream for a specific length of time. In all embodiments the nonporous layers formed are selectively permeable to hydrogen.

  4. Method for forming H2-permselective oxide membranes

    DOEpatents

    Gavalas, G.R.; Nam, S.W.; Tsapatsis, M.; Kim, S.

    1995-09-26

    Methods are disclosed for forming permselective oxide membranes that are highly selective to permeation of hydrogen by chemical deposition of reactants in the pore of porous tubes, such as Vycor{trademark} glass or Al{sub 2}O{sub 3} tubes. The porous tubes have pores extending through the tube wall. The process involves forming a stream containing a first reactant of the formula RX{sub n}, wherein R is silicon, titanium, boron or aluminum, X is chlorine, bromine or iodine, and n is a number which is equal to the valence of R; and forming another stream containing water vapor as the second reactant. Both of the reactant streams are passed along either the outside or the inside surface of a porous tube and the streams react in the pores of the porous tube to form a nonporous layer of R-oxide in the pores. The membranes are formed by the hydrolysis of the respective halides. In another embodiment, the first reactant stream contains a first reactant having the formula SiH{sub n}Cl{sub 4{minus}n} where n is 1, 2 or 3; and the second reactant stream contains water vapor and oxygen. In still another embodiment the first reactant stream containing a first reactant selected from the group consisting of Cl{sub 3}SiOSiCl{sub 3}, Cl{sub 3}SiOSiCl{sub 2}OSiCl{sub 3}, and mixtures thereof and the second reactant stream contains water vapor. In still another embodiment, membrane formation is carried out by an alternating flow deposition method. This involves a sequence of cycles, each cycle comprising introduction of the halide-containing stream and allowance of a specific time for reaction followed by purge and flow of the water vapor containing stream for a specific length of time. In all embodiments the nonporous layers formed are selectively permeable to hydrogen. 11 figs.

  5. An advanced deterministic method for spent fuel criticality safety analysis

    SciTech Connect

    DeHart, M.D.

    1998-01-01

    Over the past two decades, criticality safety analysts have come to rely to a large extent on Monte Carlo methods for criticality calculations. Monte Carlo has become popular because of its capability to model complex, non-orthogonal configurations or fissile materials, typical of real world problems. Over the last few years, however, interest in determinist transport methods has been revived, due shortcomings in the stochastic nature of Monte Carlo approaches for certain types of analyses. Specifically, deterministic methods are superior to stochastic methods for calculations requiring accurate neutron density distributions or differential fluxes. Although Monte Carlo methods are well suited for eigenvalue calculations, they lack the localized detail necessary to assess uncertainties and sensitivities important in determining a range of applicability. Monte Carlo methods are also inefficient as a transport solution for multiple pin depletion methods. Discrete ordinates methods have long been recognized as one of the most rigorous and accurate approximations used to solve the transport equation. However, until recently, geometric constraints in finite differencing schemes have made discrete ordinates methods impractical for non-orthogonal configurations such as reactor fuel assemblies. The development of an extended step characteristic (ESC) technique removes the grid structure limitations of traditional discrete ordinates methods. The NEWT computer code, a discrete ordinates code built upon the ESC formalism, is being developed as part of the SCALE code system. This paper will demonstrate the power, versatility, and applicability of NEWT as a state-of-the-art solution for current computational needs.

  6. The molecular basis of social behavior: models, methods and advances.

    PubMed

    LeBoeuf, Adria C; Benton, Richard; Keller, Laurent

    2013-02-01

    Elucidating the molecular and neural basis of complex social behaviors such as communal living, division of labor and warfare requires model organisms that exhibit these multi-faceted behavioral phenotypes. Social insects, such as ants, bees, wasps and termites, are attractive models to address this problem, with rich ecological and ethological foundations. However, their atypical systems of reproduction have hindered application of classical genetic approaches. In this review, we discuss how recent advances in social insect genomics, transcriptomics, and functional manipulations have enhanced our ability to observe and perturb gene expression, physiology and behavior in these species. Such developments begin to provide an integrated view of the molecular and cellular underpinnings of complex social behavior. PMID:22995551

  7. Recent advances in neutral particle transport methods and codes

    NASA Astrophysics Data System (ADS)

    Azmy, Yousry Y.

    1997-02-01

    An overview of Oak Ridge National Laboratory's (ORNL) 3D neural particle transport code, TORT, is presented. Special features of the code that make it invaluable for large applications are summarized for the prospective user. Advanced capabilities currently under development and installation in the production release of TORT are discussed in some detail. These include: multitasking on Cray platforms running the UNICOS operating system; adjacent-cell preconditioning acceleration scheme; and graphics codes for displaying computed quantities such as the flux. Further developments for TORT and its companion codes to enhance its present capabilities, as well as expand its range of applications will be discussed. Speculation on the next generation of neutral particle transport codes at ORNL, especially regarding unstructured grids and high order spatial approximations, will also be mentioned.

  8. Advances in microfluidics-based experimental methods for neuroscience research.

    PubMed

    Park, Jae Woo; Kim, Hyung Joon; Kang, Myeong Woo; Jeon, Noo Li

    2013-02-21

    The application of microfluidics to neuroscience applications has always appealed to neuroscientists because of the capability to control the cellular microenvironment in both a spatial and temporal manner. Recently, there has been rapid development of biological micro-electro-mechanical systems (BioMEMS) for both fundamental and applied neuroscience research. In this review, we will discuss the applications of BioMEMS to various topics in the field of neuroscience. The purpose of this review is to summarise recent advances in the components and design of the BioMEMS devices, in vitro disease models, electrophysiology and neural stem cell research. We envision that microfluidics will play a key role in future neuroscience research, both fundamental and applied research.

  9. Recent advances in neutral particle transport methods and codes

    SciTech Connect

    Azmy, Y.Y.

    1996-06-01

    An overview of ORNL`s three-dimensional neutral particle transport code, TORT, is presented. Special features of the code that make it invaluable for large applications are summarized for the prospective user. Advanced capabilities currently under development and installation in the production release of TORT are discussed; they include: multitasking on Cray platforms running the UNICOS operating system; Adjacent cell Preconditioning acceleration scheme; and graphics codes for displaying computed quantities such as the flux. Further developments for TORT and its companion codes to enhance its present capabilities, as well as expand its range of applications are disucssed. Speculation on the next generation of neutron particle transport codes at ORNL, especially regarding unstructured grids and high order spatial approximations, are also mentioned.

  10. Comparison of Advanced Distillation Control Methods, Final Technical Report

    SciTech Connect

    Dr. James B. Riggs

    2000-11-30

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to evaluate configuration selections for single-ended and dual-composition control, as well as to compare conventional and advanced control approaches. In addition, a simulator of a main fractionator was used to compare the control performance of conventional and advanced control. For each case considered, the controllers were tuned by using setpoint changes and tested using feed composition upsets. Proportional Integral (PI) control performance was used to evaluate the configuration selection problem. For single ended control, the energy balance configuration was found to yield the best performance. For dual composition control, nine configurations were considered. It was determined that the use of dynamic simulations is required in order to identify the optimum configuration from among the nine possible choices. The optimum configurations were used to evaluate the relative control performance of conventional PI controllers, MPC (Model Predictive Control), PMBC (Process Model-Based Control), and ANN (Artificial Neural Networks) control. It was determined that MPC works best when one product is much more important than the other, while PI was superior when both products were equally important. PMBC and ANN were not found to offer significant advantages over PI and MPC. MPC was found to outperform conventional PI control for the main fractionator. MPC was applied to three industrial columns: one at Phillips Petroleum and two at Union Carbide. In each case, MPC was found to significantly outperform PI controls. The major advantage of the MPC controller is its ability to effectively handle a complex set of constraints and control objectives.

  11. Application of advanced oxidation processes for cleaning of industrial water generated in wet dedusting of shaft furnace gases.

    PubMed

    Czaplicka, Marianna; Kurowski, Ryszard; Jaworek, Katarzyna; Bratek, Łukasz

    2013-01-01

    The paper presents results of studies into advanced oxidation processes in 03 and 03/UV systems. An advanced oxidation process (AOP) was conducted to reduce the load of impurities in circulating waters from wet de-dusting of shaft furnace gases. Besides inorganic impurities, i.e. mainly arsenic compounds (16 g As L(-1) on average), lead, zinc, chlorides and sulphates, the waters also contain some organic material. The organic material is composed of a complex mixture that contains, amongst others, aliphatic compounds, phenol and its derivatives, pyridine bases, including pyridine, and its derivatives. The test results show degradation of organic and inorganic compounds during ozonation and photo-oxidation processes. Analysis of the solutions from the processes demonstrated that the complex organic material in the industrial water was oxidized in ozonation and in photo-oxidation, which resulted in formation of aldehydes and carboxylic acids. Kinetic degradation of selected pollutants is presented. Obtained results indicated that the O3/UV process is more effective in degradation of organic matter than ozonation. Depending on the process type, precipitation of the solid phase was observed. The efficiency of solid-phase formation was higher in photo-oxidation with ozone. It was found that the precipitated solid phase is composed mainly of arsenic, iron and oxygen. PMID:24191479

  12. METHOD FOR THE PREPARATION OF STABLE ACTINIDE METAL OXIDE-CONTAINING SLURRIES AND OF THE OXIDES THEREFOR

    DOEpatents

    Hansen, R.S.; Minturn, R.E.

    1958-02-25

    This patent deals with a method of preparing actinide metal oxides of a very fine particle size and of forming stable suspensions therefrom. The process consists of dissolving the nitrate of the actinide element in a combustible organic solvent, converting the solution obtained into a spray, and igniting the spray whereby an oxide powder is obtained. The oxide powder is then slurried in an aqueous soiution of a substance which is adsorbable by said oxides, dspersed in a colloid mill whereby a suspension is obtained, and electrodialyzed until a low spectiic conductance is reached.

  13. Method of electrode fabrication for solid oxide electrochemical cells

    DOEpatents

    Jensen, Russell R.

    1990-01-01

    A process for fabricating cermet electrodes for solid oxide electrochemical cells by sintering is disclosed. First, a porous metal electrode is fabricated on a solid oxide cell, such as a fuel cell by, for example, sintering, and is then infiltrated with a high volume fraction stabilized zirconia suspension. A second sintering step is used to sinter the infiltrated zirconia to a high density in order to more securely attach the electrode to the solid oxide electrolyte of the cell. High performance fuel electrodes can be obtained with this process. Further electrode performance enhancement may be achieved if stabilized zirconia doped with cerium oxide, chromium oxide, titanium oxide, and/or praseodymium oxide for electronic conduction is used.

  14. Method of electrode fabrication for solid oxide electrochemical cells

    DOEpatents

    Jensen, R.R.

    1990-11-20

    A process for fabricating cermet electrodes for solid oxide electrochemical cells by sintering is disclosed. First, a porous metal electrode is fabricated on a solid oxide cell, such as a fuel cell by, for example, sintering, and is then infiltrated with a high volume fraction stabilized zirconia suspension. A second sintering step is used to sinter the infiltrated zirconia to a high density in order to more securely attach the electrode to the solid oxide electrolyte of the cell. High performance fuel electrodes can be obtained with this process. Further electrode performance enhancement may be achieved if stabilized zirconia doped with cerium oxide, chromium oxide, titanium oxide, and/or praseodymium oxide for electronic conduction is used. 5 figs.

  15. Applicability of fluidized bed reactor in recalcitrant compound degradation through advanced oxidation processes: a review.

    PubMed

    Tisa, Farhana; Abdul Raman, Abdul Aziz; Wan Daud, Wan Mohd Ashri

    2014-12-15

    Treatment of industrial waste water (e.g. textile waste water, phenol waste water, pharmaceutical etc) faces limitation in conventional treatment procedures. Advanced oxidation processes (AOPs) do not suffer from the limits of conventional treatment processes and consequently degrade toxic pollutants more efficiently. Complexity is faced in eradicating the restrictions of AOPs such as sludge formation, toxic intermediates formation and high requirement for oxidants. Increased mass-transfer in AOPs is an alternate solution to this problem. AOPs combined with Fluidized bed reactor (FBR) can be a potential choice compared to fixed bed or moving bed reactor, as AOP catalysts life-span last for only maximum of 5-10 cycles. Hence, FBR-AOPs require lesser operational and maintenance cost by reducing material resources. The time required for AOP can be minimized using FBR and also treatable working volume can be increased. FBR-AOP can process from 1 to 10 L of volume which is 10 times more than simple batch reaction. The mass transfer is higher thus the reaction time is lesser. For having increased mass transfer sludge production can be successfully avoided. The review study suggests that, optimum particle size, catalyst to reactor volume ratio, catalyst diameter and liquid or gas velocity is required for efficient FBR-AOP systems. However, FBR-AOPs are still under lab-scale investigation and for industrial application cost study is needed. Cost of FBR-AOPs highly depends on energy density needed and the mechanism of degradation of the pollutant. The cost of waste water treatment containing azo dyes was found to be US$ 50 to US$ 500 per 1000 gallons where, the cost for treating phenol water was US$ 50 to US$ 800 per 1000 gallons. The analysis for FBR-AOP costs has been found to depend on the targeted pollutant, degradation mechanism (zero order, 1st order and 2nd order) and energy consumptions by the AOPs.

  16. Applicability of fluidized bed reactor in recalcitrant compound degradation through advanced oxidation processes: a review.

    PubMed

    Tisa, Farhana; Abdul Raman, Abdul Aziz; Wan Daud, Wan Mohd Ashri

    2014-12-15

    Treatment of industrial waste water (e.g. textile waste water, phenol waste water, pharmaceutical etc) faces limitation in conventional treatment procedures. Advanced oxidation processes (AOPs) do not suffer from the limits of conventional treatment processes and consequently degrade toxic pollutants more efficiently. Complexity is faced in eradicating the restrictions of AOPs such as sludge formation, toxic intermediates formation and high requirement for oxidants. Increased mass-transfer in AOPs is an alternate solution to this problem. AOPs combined with Fluidized bed reactor (FBR) can be a potential choice compared to fixed bed or moving bed reactor, as AOP catalysts life-span last for only maximum of 5-10 cycles. Hence, FBR-AOPs require lesser operational and maintenance cost by reducing material resources. The time required for AOP can be minimized using FBR and also treatable working volume can be increased. FBR-AOP can process from 1 to 10 L of volume which is 10 times more than simple batch reaction. The mass transfer is higher thus the reaction time is lesser. For having increased mass transfer sludge production can be successfully avoided. The review study suggests that, optimum particle size, catalyst to reactor volume ratio, catalyst diameter and liquid or gas velocity is required for efficient FBR-AOP systems. However, FBR-AOPs are still under lab-scale investigation and for industrial application cost study is needed. Cost of FBR-AOPs highly depends on energy density needed and the mechanism of degradation of the pollutant. The cost of waste water treatment containing azo dyes was found to be US$ 50 to US$ 500 per 1000 gallons where, the cost for treating phenol water was US$ 50 to US$ 800 per 1000 gallons. The analysis for FBR-AOP costs has been found to depend on the targeted pollutant, degradation mechanism (zero order, 1st order and 2nd order) and energy consumptions by the AOPs. PMID:25190594

  17. Expression of the Receptor for Advanced Glycation End Products in Oligodendrocytes in Response to Oxidative Stress

    PubMed Central

    Qin, Jingdong; Goswami, Rajendra; Dawson, Sylvia; Dawson, Glyn

    2008-01-01

    Demyelination is a common result of oxidative stress in the nervous system, and we report here that the response of oligodendrocytes to oxidative stress involves the receptor for advanced glycation end products (RAGE). RAGE has not previously been reported in neonatal rat oligodendrocytes (NRO), but, by using primers specific for rat RAGE, we were able to show expression of messenger RNA (mRNA) for RAGE in NRO, and a 55-kDa protein was detected by Western blotting with antibodies to RAGE. Neonatal rat oligodendrocytes stained strongly for RAGE, suggesting membrane localization of RAGE. Addition of low concentrations of hydrogen peroxide (100 μM) initiated 55-kDa RAGE shedding from the cell membrane and the appearance of “soluble” 45-kDa RAGE in the culture medium, followed by restoration of RAGE expression to normal levels. Increasing hydrogen peroxide concentration (>200 μM) resulted in no restoration of RAGE, and the cells underwent apoptosis and necrosis. We further confirmed the observation in a human oligodendroglioma-derived (HOG) cell line. Both the antioxidant N-acetyl-L-cysteine and the broad-spectrum metalloproteases inhibitor TAPI0 were able partially to inhibit shedding of RAGE, suggesting involvement of metalloproteases in cleavage to produce soluble RAGE. The level of 55-kDa RAGE in autopsy brain of patients undergoing neurodegeneration with accompanying inflammation [multiple sclerosis and neuronal ceroid-lipofuscinosis (Batten's disease)] was much lower than that in age-matched controls, suggesting that shedding of RAGE might occur as reactive oxygen species accumulate in brain cells and be part of the process of neurodegeneration. PMID:18438937

  18. Advanced treatment of biologically pretreated coal gasification wastewater by a novel heterogeneous Fenton oxidation process.

    PubMed

    Zhuang, Haifeng; Han, Hongjun; Ma, Wencheng; Hou, Baolin; Jia, Shengyong; Zhao, Qian

    2015-07-01

    Sewage sludge from a biological wastewater treatment plant was converted into sewage sludge based activated carbon (SBAC) with ZnCl2 as activation agent, which was used as a support for ferric oxides to form a catalyst (FeOx/SBAC) by a simple impregnation method. The new material was then used to improve the performance of Fenton oxidation of real biologically pretreated coal gasification wastewater (CGW). The results indicated that the prepared FeOx/SBAC significantly enhanced the pollutant removal performance in the Fenton process, so that the treated wastewater was more biodegradable and less toxic. The best performance was obtained over a wide pH range from 2 to 7, temperature 30°C, 15 mg/L of H2O2 and 1g/L of catalyst, and the treated effluent concentrations of COD, total phenols, BOD5 and TOC all met the discharge limits in China. Meanwhile, on the basis of significant inhibition by a radical scavenger in the heterogeneous Fenton process as well as the evolution of FT-IR spectra of pollutant-saturated FeOx/BAC with and without H2O2, it was deduced that the catalytic activity was responsible for generating hydroxyl radicals, and a possible reaction pathway and interface mechanism were proposed. Moreover, FeOx/SBAC showed superior stability over five successive oxidation runs. Thus, heterogeneous Fenton oxidation of biologically pretreated CGW by FeOx/SBAC, with the advantages of being economical, efficient and sustainable, holds promise for engineering application.

  19. Advanced oxidation protein products induce apoptosis in podocytes through induction of endoplasmic reticulum stress.

    PubMed

    Rong, Guang; Tang, Xun; Guo, Tingting; Duan, Na; Wang, Yue; Yang, Lei; Zhang, Jun; Liang, Xiujie

    2015-09-01

    Although podocyte apoptosis has been shown to be induced by the accumulation of advanced oxidation protein products (AOPPs), the mechanisms through which AOPPs trigger apoptosis in these cells remain unclear. In this study, we investigated the role of endoplasmic reticulum (ER) stress in AOPP-induced podocyte apoptosis. AOPP treatment induced overexpression of glucose-regulated protein 78 and CCAAT/enhancer-binding protein-homologous protein (CHOP) in podocytes, indicating that AOPPs induced ER stress. Notably, AOPP-induced increase in the rate of podocyte apoptosis was partly reversed by salubrinal, an ER stress inhibitor, whereas the AOPP effect was reproduced by an inducer of ER stress, thapsigargin, suggesting that AOPPs triggered podocyte apoptosis by inducing ER stress. Furthermore, AOPP-induced reactive oxygen species (ROS) generation, ER stress, and podocyte apoptosis were significantly inhibited by an nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor, a ROS scavenger, or receptor of advanced glycation end products (RAGE) small interfering RNA (siRNA). Moreover, silencing of the three ER stress sensors, protein kinase-like ER kinase (PERK), activating transcription factor 6 (ATF6), and inositol requiring 1 (IRE1), respectively, significantly lowered the apoptotic rate of the cells compared with that of the scramble siRNA-transfected cells. Lastly, our data suggested that CHOP- and caspase-12-dependent pathways were involved in ER stress-mediated podocyte apoptosis and that Bcl-2 suppression was involved in CHOP-mediated apoptosis. Collectively, our results indicate for the first time that AOPPs trigger podocyte apoptosis through induction of ER stress, which might be regulated by NADPH oxidase-dependent ROS through RAGE, and that this apoptosis is mediated by three unfolded protein response pathways, the PERK, ATF6, and IRE1 pathways, and the mediators, CHOP and caspase-12. PMID:26197866

  20. [Effects of organic pollutants in drinking water on the removal of dimethyl phthalate by advanced oxidation processes].

    PubMed

    Rui, Min; Gao, Nai-yun; Xu, Bin; Li, Fu-sheng; Zhao, Jian-fu; Le, Lin-sheng

    2006-12-01

    Humic acids were used to simulate natural organic compounds in water for the investigation of DMP oxidation by three different AOPs (advanced oxidation processes) of UV-H2O2, O3 and UV-O3. The results showed that pseudo-first-order reaction equation could describe the oxidation of DMP by UV-H2O2 perfectly, which was strongly affected humic acids in water. The relationship between pseudo-first-order reaction rate and TOC value could be expressed as K = 0. 162 0 [TOC]-0.8171. It was also found that humic acids in the water exhibited obvious influence on the oxidation of DMP by UV-O3. However, effect of humic acids on the oxidation of DMP by ozone was not obvious. It was also analyzed that oxidation of DMP was dominated by ozone oxidation both in ozonation process and UV-O3 process; the importance of "OH in the oxidation of DMP was enhanced as the concentration of DMP decreased in UV-O3 process. The degree of impact form humic acids towards different AOPs could be ranked in a decreasing order as UV-H2O3, UV-O3, 03. PMID:17304847

  1. UVA Light-excited Kynurenines Oxidize Ascorbate and Modify Lens Proteins through the Formation of Advanced Glycation End Products

    PubMed Central

    Linetsky, Mikhail; Raghavan, Cibin T.; Johar, Kaid; Fan, Xingjun; Monnier, Vincent M.; Vasavada, Abhay R.; Nagaraj, Ram H.

    2014-01-01

    Advanced glycation end products (AGEs) contribute to lens protein pigmentation and cross-linking during aging and cataract formation. In vitro experiments have shown that ascorbate (ASC) oxidation products can form AGEs in proteins. However, the mechanisms of ASC oxidation and AGE formation in the human lens are poorly understood. Kynurenines are tryptophan oxidation products produced from the indoleamine 2,3-dioxygenase (IDO)-mediated kynurenine pathway and are present in the human lens. This study investigated the ability of UVA light-excited kynurenines to photooxidize ASC and to form AGEs in lens proteins. UVA light-excited kynurenines in both free and protein-bound forms rapidly oxidized ASC, and such oxidation occurred even in the absence of oxygen. High levels of GSH inhibited but did not completely block ASC oxidation. Upon UVA irradiation, pigmented proteins from human cataractous lenses also oxidized ASC. When exposed to UVA light (320–400 nm, 100 milliwatts/cm2, 45 min to 2 h), young human lenses (20–36 years), which contain high levels of free kynurenines, lost a significant portion of their ASC content and accumulated AGEs. A similar formation of AGEs was observed in UVA-irradiated lenses from human IDO/human sodium-dependent vitamin C transporter-2 mice, which contain high levels of kynurenines and ASC. Our data suggest that kynurenine-mediated ASC oxidation followed by AGE formation may be an important mechanism for lens aging and the development of senile cataracts in humans. PMID:24798334

  2. Photocatalytic oxidation of nitric oxide with immobilized titanium dioxide films synthesized by hydrothermal method.

    PubMed

    Wu, Zhongbiao; Wang, Haiqiang; Liu, Yue; Gu, Zhuoliang

    2008-02-28

    Gas-phase photocatalytic oxidation (PCO) of nitric oxide (NO) with immobilized TiO2 films was studied in this paper. The immobilized TiO2 films were synthesized by hydrothermal method. The characterization for the physicochemical properties of catalysts prepared under different hydrothermal conditions were carried out by X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), high resolution-transmission electron microscopy (HR-TEM), Brunauer-Emmett-Teller measurements (BET) and scanning electron micrograph (SEM). It was found that the PCO efficiency of the catalyst was mainly depended on the hydrothermal conditions. The optimal values of hydrothermal temperature and hydrothermal time were 200 degrees C and 24 h, respectively. Furthermore, it was also known that the photocatalytic efficiency would decrease remarkably when the calcination temperature was over than 450 degrees C. Under the optimal conditions (hydrothermal condition: 200 degrees C for 24 h; calcination temperature: 450 degrees C), the photocatalytic efficiency of catalyst could reach 60% higher than that of Degussa P25.

  3. Adherence to Scientific Method while Advancing Exposure Science

    EPA Science Inventory

    Paul Lioy was simultaneously a staunch adherent to the scientific method and an innovator of new ways to conduct science, particularly related to human exposure. Current challenges to science and the application of the scientific method are presented as they relate the approaches...

  4. [Recent advances in sample preparation methods of plant hormones].

    PubMed

    Wu, Qian; Wang, Lus; Wu, Dapeng; Duan, Chunfeng; Guan, Yafeng

    2014-04-01

    Plant hormones are a group of naturally occurring trace substances which play a crucial role in controlling the plant development, growth and environment response. With the development of the chromatography and mass spectroscopy technique, chromatographic analytical method has become a widely used way for plant hormone analysis. Among the steps of chromatographic analysis, sample preparation is undoubtedly the most vital one. Thus, a highly selective and efficient sample preparation method is critical for accurate identification and quantification of phytohormones. For the three major kinds of plant hormones including acidic plant hormones & basic plant hormones, brassinosteroids and plant polypeptides, the sample preparation methods are reviewed in sequence especially the recently developed methods. The review includes novel methods, devices, extractive materials and derivative reagents for sample preparation of phytohormones analysis. Especially, some related works of our group are included. At last, the future developments in this field are also prospected.

  5. Advances in spectroscopic methods for quantifying soil carbon

    USGS Publications Warehouse

    Liebig, Mark; Franzluebbers, Alan J.; Follett, Ronald F.; Hively, W. Dean; Reeves, James B.; McCarty, Gregory W.; Calderon, Francisco

    2012-01-01

    The gold standard for soil C determination is combustion. However, this method requires expensive consumables, is limited to the determination of the total carbon and in the number of samples which can be processed (~100/d). With increased interest in soil C sequestration, faster methods are needed. Thus, interest in methods based on diffuse reflectance spectroscopy in the visible, near-infrared or mid-infrared ranges using either proximal or remote sensing. These methods have the ability to analyze more samples (2 to 3X/d) or huge areas (imagery) and do multiple analytes simultaneously, but require calibrations relating spectral and reference data and have specific problems, i.e., remote sensing is capable of scanning entire watersheds, thus reducing the sampling needed, but is limiting to the surface layer of tilled soils and by difficulty in obtaining proper calibration reference values. The objective of this discussion is the present state of spectroscopic methods for soil C determination.

  6. Oxidative treatment characteristics of biotreated textile-dyeing wastewater and chemical agents used in a textile-dyeing process by advanced oxidation process.

    PubMed

    Lim, B R; Hu, H Y; Ahn, K H; Fujie, K

    2004-01-01

    The oxidative treatment characteristics of biotreated textile-dyeing wastewater and typical chemicals such as desizing, scouring, dispersing and swelling agents used in the textile-dyeing process by advanced oxidation process were experimentally studied. The refractory organic matters remained in the effluent of biological treatment process without degradation may be suitable for the improvement of biodegradability and mineralized to CO2 by combined ozonation with and without hydrogen peroxide. On the other hand, the refractory chemicals contained in the scouring agent A and swelling agent may not be mineralized and their biodegradability may not be improved by ozonation. However, the BOD/DOC ratio of scouring agent B increased from 0.3 to 0.45 after ozonation. Based on the results described above, advanced treatment process involving the ozonation without and with the addition of hydrogen peroxide, followed by biological treatment was proposed for the treatment of refractory wastewater discharged from the textile-dyeing process.

  7. Dechlorination of chlorophenols found in pulp bleach plant E-1 effluents by advanced oxidation processes.

    PubMed

    Wang, Rui; Chen, Chen-Loung; Gratzl, Josef S

    2005-05-01

    Studies were conducted on the response of 2,4,6-trichlorophenol (1), 2,3,4,5-tetrachloro-phenol (2) and 4,5-dichloroguaiacol (3) toward advanced oxidation processes, such as UV-, O2/UV-, H2O2/UV-, O3/UV- and O3-H2O2/UV-photolyses with irradiation of 254 nm photons. The compounds 1-3 are among the chlorophenols found in the Kraft-pulp bleach plant E-1 effluents. The studies were extended to treatment of these compounds with ozonation and O3-H2O2 oxidation systems in alkaline aqueous solution. Except for the O2/UV-photolysis of 1 and H2O2/UV-photolysis of 2, the dechlorination of 1-3 by O2/UV- and H2O2/UV-potolyses were less effective than the corresponding N2UV-potolysis of 1-3. Guaiacol-type chlorophenols were more readily able to undergo dechlorination than non-guaiacol type chlorophenols by N2/UV-, O2/UV- and H2O2/UV-potolyses. In addition, the efficiency for the dechlorination of 1-3 by N2/UV-, O2/UV- and H2O2/UV-potolyses appeared to be dependent upon the inductive and resonance effects of substituents as well as number and position of chlorine substituent in the aromatic ring of the compounds. The dechlorination of 2 by treatment with O3 alone is slightly more effective than the corresponding the O3/UV-photlysis, whereas the dechlorination of 2 by treatment with the combination of O3 and H2O2 was slightly less effective than the corresponding O3-H2O2/UV-photolysis. In contrast, the dechlorination of 3 on treatment with O3 alone was slightly less effective than the corresponding the O3/UV-photolysis, whereas the dechlorination of 3 on treatment with the combination of O3 and H2O2 was slightly more effective than the corresponding the O3-H2O2/UV-photolysis. In the dechlorination of 2 and 3, chemical species derived from ozone and hydrogen peroxide in alkaline solution were dominant reactions in the O3/UV- and O3-H2O2/UV-photolysis systems as in the O3 and O3-H2O2 oxidation systems. Possible dechlorination mechanisms involved were discussed on the basis of

  8. Preface: Special Topic Section on Advanced Electronic Structure Methods for Solids and Surfaces

    SciTech Connect

    Michaelides, Angelos; Martinez, Todd J.; Alavi, Ali; Kresse, Georg

    2015-09-14

    This Special Topic section on Advanced Electronic Structure Methods for Solids and Surfaces contains a collection of research papers that showcase recent advances in the high accuracy prediction of materials and surface properties. It provides a timely snapshot of a growing field that is of broad importance to chemistry, physics, and materials science.

  9. Integrating Advanced High School Chemistry Research with Organic Chemistry and Instrumental Methods of Analysis

    ERIC Educational Resources Information Center

    Kennedy, Brian J.

    2008-01-01

    This paper describes and discusses the unique chemistry course opportunities beyond the advanced placement-level available at a science and technology magnet high school. Students may select entry-level courses such as honors and advanced placement chemistry; they may also take electives in organic chemistry with instrumental methods of analysis;…

  10. Comparison of advanced distillation control methods. Fourth annual report

    SciTech Connect

    Riggs, J.B.

    1998-09-01

    Detailed dynamic simulations of three industrial columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to evaluate configuration selection for single-ended and dual-composition control as well as compare conventional and advanced control approaches. For each case considered, the controllers were tuned by using setpoint changes and tested using feed composition upsets. Proportional Integral (PI) control performance was used to evaluate the configuration selection problem. For single ended control, the energy balance configuration was found to yield the best performance. For dual composition control, nine configurations were considered. It was determined that in order to identify the optimum configuration, detailed testing using dynamic simulation is required. The optimum configurations were used to evaluate the control performance of conventional PI controllers, DMC (Dynamic Matrix Control), PMBC (Process Model Based Control), and ANN (Artificial Neural Networks) control. It was determined that DMC works best when one product is much more important than the other while PI was superior when both products were equally important. PMBC and ANN were not found to offer significant advantages over PI and DMC.

  11. Review: Advances in delta-subsidence research using satellite methods

    NASA Astrophysics Data System (ADS)

    Higgins, Stephanie A.

    2016-05-01

    Most of the world's major river deltas are sinking relative to local sea level. The effects of subsidence can include aquifer salinization, infrastructure damage, increased vulnerability to flooding and storm surges, and permanent inundation of low-lying land. Consequently, determining the relative importance of natural vs. anthropogenic pressures in driving delta subsidence is a topic of ongoing research. This article presents a review of knowledge with respect to delta surface-elevation loss. The field is rapidly advancing due to applications of space-based techniques: InSAR (interferometric synthetic aperture radar), GPS (global positioning system), and satellite ocean altimetry. These techniques have shed new light on a variety of subsidence processes, including tectonics, isostatic adjustment, and the spatial and temporal variability of sediment compaction. They also confirm that subsidence associated with fluid extraction can outpace sea-level rise by up to two orders of magnitude, resulting in effective sea-level rise that is one-hundred times faster than the global average rate. In coming years, space-based and airborne instruments will be critical in providing near-real-time monitoring to facilitate management decisions in sinking deltas. However, ground-based observations continue to be necessary for generating complete measurements of surface-elevation change. Numerical modeling should seek to simulate couplings between subsidence processes for greater predictive power.

  12. Investigation of advancing front method for generating unstructured grid

    NASA Astrophysics Data System (ADS)

    Thomas, A. M.; Tiwari, S. N.

    1992-06-01

    The advancing front technique is used to generate an unstructured grid about simple aerodynamic geometries. Unstructured grids are generated using VGRID2D and VGRID3D software. Specific problems considered are a NACA 0012 airfoil, a bi-plane consisting of two NACA 0012 airfoil, a four element airfoil in its landing configuration, and an ONERA M6 wing. Inviscid time dependent solutions are computed on these geometries using USM3D and the results are compared with standard test results obtained by other investigators. A grid convergence study is conducted for the NACA 0012 airfoil and compared with a structured grid. A structured grid is generated using GRIDGEN software and inviscid solutions computed using CFL3D flow solver. The results obtained by unstructured grid for NACA 0012 airfoil showed an asymmetric distribution of flow quantities, and a fine distribution of grid was required to remove this asymmetry. On the other hand, the structured grid predicted a very symmetric distribution, but when the total number of points were compared to obtain the same results it was seen that structured grid required more grid points.

  13. Health, wealth, and air pollution: advancing theory and methods.

    PubMed Central

    O'Neill, Marie S; Jerrett, Michael; Kawachi, Ichiro; Levy, Jonathan I; Cohen, Aaron J; Gouveia, Nelson; Wilkinson, Paul; Fletcher, Tony; Cifuentes, Luis; Schwartz, Joel

    2003-01-01

    The effects of both ambient air pollution and socioeconomic position (SEP) on health are well documented. A limited number of recent studies suggest that SEP may itself play a role in the epidemiology of disease and death associated with exposure to air pollution. Together with evidence that poor and working-class communities are often more exposed to air pollution, these studies have stimulated discussion among scientists, policy makers, and the public about the differential distribution of the health impacts from air pollution. Science and public policy would benefit from additional research that integrates the theory and practice from both air pollution and social epidemiologies to gain a better understanding of this issue. In this article we aim to promote such research by introducing readers to methodologic and conceptual approaches in the fields of air pollution and social epidemiology; by proposing theories and hypotheses about how air pollution and socioeconomic factors may interact to influence health, drawing on studies conducted worldwide; by discussing methodologic issues in the design and analysis of studies to determine whether health effects of exposure to ambient air pollution are modified by SEP; and by proposing specific steps that will advance knowledge in this field, fill information gaps, and apply research results to improve public health in collaboration with affected communities. PMID:14644658

  14. Advances in spectroscopic methods for quantifying soil carbon

    USGS Publications Warehouse

    Reeves, James B.; McCarty, Gregory W.; Calderon, Francisco; Hively, W. Dean

    2012-01-01

    The current gold standard for soil carbon (C) determination is elemental C analysis using dry combustion. However, this method requires expensive consumables, is limited by the number of samples that can be processed (~100/d), and is restricted to the determination of total carbon. With increased interest in soil C sequestration, faster methods of analysis are needed, and there is growing interest in methods based on diffuse reflectance spectroscopy in the visible, near-infrared or mid-infrared spectral ranges. These spectral methods can decrease analytical requirements and speed sample processing, be applied to large landscape areas using remote sensing imagery, and be used to predict multiple analytes simultaneously. However, the methods require localized calibrations to establish the relationship between spectral data and reference analytical data, and also have additional, specific problems. For example, remote sensing is capable of scanning entire watersheds for soil carbon content but is limited to the surface layer of tilled soils and may require difficult and extensive field sampling to obtain proper localized calibration reference values. The objective of this chapter is to discuss the present state of spectroscopic methods for determination of soil carbon.

  15. Short-Term Oxidation Studies on Nicrofer- 6025HT in Air at Elevated Temperatures for Advanced Coal Based Power Plants

    SciTech Connect

    Joshi, Vineet V.; Meier, Alan; Darsell, Jens T.; Nachimuthu, Ponnusamy; Bowden, Mark E.; Weil, K. Scott

    2013-04-01

    Several advanced air separation unit (ASU) designs being considered for use in coal gasification rely on the use of solid state mixed ionic and electronic conductors. Nicrofer-6025HT, a nickel-based alloy, has been identified as a potential manifold material to transport the hot gases into the ASUs. In the current study, isothermal oxidation tests were conducted on Nicrofer-6025HT in the temperature range of 700–900 °C for up to 24 h. The evolution of oxide scale was evaluated using SEM, XRD, and XPS. The composite surface oxide layer that formed consisted of an outer chromia-rich scale and an inner alumina scale. For the longer times at the higher temperatures evaluated, a NiCr2O4 spinel phase was located at the interface between the alumina and chromia. Based on the experimental results a four-step oxidation model was proposed.

  16. Numerical approximation of a nonlinear delay-advance functional differential equation by a finite element method

    NASA Astrophysics Data System (ADS)

    Teodoro, M. F.

    2012-09-01

    We are particularly interested in the numerical solution of the functional differential equations with symmetric delay and advance. In this work, we consider a nonlinear forward-backward equation, the Fitz Hugh-Nagumo equation. It is presented a scheme which extends the algorithm introduced in [1]. A computational method using Newton's method, finite element method and method of steps is developped.

  17. Quantification of Nitrous Oxide from Fugitive Emissions by Tracer Dilution Method using a Mobile Real-time Nitrous Oxide Analyzer

    NASA Astrophysics Data System (ADS)

    Mønster, J.; Rella, C.; Jacobson, G. A.; He, Y.; Hoffnagle, J.; Scheutz, C.

    2012-12-01

    Nitrous oxide is a powerful greenhouse gas considered 298 times stronger than carbon dioxide on a hundred years term (Solomon et al. 2007). The increasing global concentration is of great concern and is receiving increasing attention in various scientific and industrial fields. Nitrous oxide is emitted from both natural and anthropogenic sources. Inventories of source specific fugitive nitrous oxide emissions are often estimated on the basis of modeling and mass balance. While these methods are well-developed, actual measurements for quantification of the emissions can be a useful tool for verifying the existing estimation methods as well as providing validation for initiatives targeted at lowering unwanted nitrous oxide emissions. One approach to performing such measurements is the tracer dilution method (Galle et al. 2001), in which a tracer gas is released at the source location at a known flow. The ratio of downwind concentrations of both the tracer gas and nitrous oxide gives the ratios of the emissions rates. This tracer dilution method can be done with both stationary and mobile measurements; in either case, real-time measurements of both tracer and analyte gas is required, which places high demands on the analytical detection method. To perform the nitrous oxide measurements, a novel, robust instrument capable of real-time nitrous oxide measurements has been developed, based on cavity ring-down spectroscopy and operating in the near-infrared spectral region. We present the results of the laboratory and field tests of this instrument in both California and Denmark. Furthermore, results are presented from measurements using the mobile plume method with a tracer gas (acetylene) to quantify the nitrous oxide and methane emissions from known sources such as waste water treatment plants and composting facilities. Nitrous oxide (blue) and methane (yellow) plumes downwind from a waste water treatment facility.

  18. Conventional and advanced oxidation processes used in disinfection of treated urban wastewater.

    PubMed

    Rodríguez-Chueca, J; Ormad, M P; Mosteo, R; Sarasa, J; Ovelleiro, J L

    2015-03-01

    The purpose of the current study is to compare the inactivation of Escherichia coli in wastewater effluents using conventional treatments (chlorination) and advanced oxidation processes (AOPs) such as UV irradiation, hydrogen peroxide (H2O2)/solar irradiation, and photo-Fenton processes. In addition, an analysis of the operational costs of each treatment is carried out taking into account the optimal dosages of chemicals used. Total inactivation of bacteria (7.5 log) was achieved by means of chlorination and UV irradiation. However, bacterial regrowth was observed 6 hours after the completion of UV treatment, obtaining a disinfection value around 3 to 4 log. On the other hand, the combination H2O2/solar irradiation achieved a maximum inactivation of E. coli of 3.30 ± 0.35 log. The photo-Fenton reaction achieved a level of inactivation of 4.87 ± 0.10 log. The order of disinfection, taking into account the reagent/cost ratio of each treatment, is as follows: chlorination > UV irradiation > photo-Fenton > H2O2/sunlight irradiation.

  19. Treating solid dairy manure using microwave-enhanced advanced oxidation process.

    PubMed

    Kenge, Anju A; Liao, Ping H; Lo, Kwang V

    2009-08-01

    The microwave enhanced advanced oxidation process (MW/H(2)O(2)-AOP) was used to treat separated solid dairy manure for nutrient release and solids reduction. The MW/H(2)O(2)-AOP was conducted at a microwave temperature of 120 degrees C for 10 minutes, and at three pH conditions of 3.5, 7.3 and 12. The hydrogen peroxide dosage at approximately 2 mL per 1% TS for a 30 mL sample was used in this study, reflecting a range of 0.53-0.75 g H(2)O(2)/g dry sludge. The results indicated that substantial quantities of nutrients could be released into the solution at pH of 3.5. However, at neutral and basic conditions only volatile fatty acids and soluble chemical oxygen demand could be released. The analyses on orthophosphate, soluble chemical oxygen demands and volatile fatty acids were re-examined for dairy manure. It was found that the orthophosphate concentration for untreated samples at a higher % total solids (TS) was suppressed and lesser than actual. To overcome this difficulty, the initial orthophosphate concentration had to be measured at 0.5% TS.

  20. Treatment of dairy manure using the microwave enhanced advanced oxidation process under a continuous mode operation.

    PubMed

    Yu, Yang; Lo, Ing W; Liao, Ping H; Lo, Kwang V

    2010-11-01

    The microwave enhanced advanced oxidation process (MW/H(2)O(2)-AOP) was used to treat dairy manure for solubilization of nutrients and organic matters. This study investigated the effectiveness of the MW/H(2)O(2)-AOP under a continuous mode of operation, and compared the results to those of batch operations. The main factors affecting solubilization by the MW/H(2)O(2)-AOP were heating temperature and hydrogen peroxide dosage. Soluble chemical oxygen demand (SCOD) and volatile fatty acids (VFA) increased with an increase of microwave (MW) heating temperature; very high concentrations were obtained at 90°C. Insignificant amounts of ammonia and reducing sugars were released in all runs. An acidic pH condition was required for phosphorus solubilisation from dairy manure. The best yield was obtained at 90°C with an acid dosage of 1.0 %; about 92 % of total phosphorus and 90 % of total chemical oxygen demand were in the soluble forms. The MW/H(2)O(2)-AOP operated in a continuous operation mode showed pronounced synergistic effects between hydrogen peroxide and microwave irradiation when compared to a batch system under similar operating conditions, resulting in much better yields.

  1. Mechanisms of advanced oxidation processing on bentonite consumption reduction in foundry.

    PubMed

    Wang, Yujue; Cannon, Fred S; Komarneni, Sridhar; Voigt, Robert C; Furness, J C

    2005-10-01

    Prior full-scale foundry data have shown that when an advanced oxidation (AO) process is employed in a green sand system, the foundry needs 20-35% less makeup bentonite clay than when AO is not employed. We herein sought to explore the mechanism of this enhancement and found that AO water displaced the carbon coating of pyrolyzed carbonaceous condensates that otherwise accumulated on the bentonite surface. This was discerned by surface elemental analysis. This AO treatment restored the clay's capacity to adsorb methylene blue (as a measure of its surface charge) and water vapor (as a reflection of its hydrophilic character). In full-scale foundries, these parameters have been tied to improved green compressive strength and mold performance. When baghouse dust from a full-scale foundry received ultrasonic treatment in the lab, 25-30% of the dust classified into the clay-size fraction, whereas only 7% classified this way without ultrasonics. Also, the ultrasonication caused a size reduction of the bentonite due to the delamination of bentonite particles. The average bentonite particle diameter decreased from 4.6 to 3 microm, while the light-scattering surface area increased over 50% after 20 min ultrasonication. This would greatly improve the bonding efficiency of the bentonite according to the classical clay bonding mechanism. As a combined result of these mechanisms, the reduced bentonite consumption in full-scale foundries could be accounted for. PMID:16245849

  2. LiNiFe-based layered structure oxide and composite for advanced single layer fuel cells

    NASA Astrophysics Data System (ADS)

    Zhu, Bin; Fan, Liangdong; Deng, Hui; He, Yunjune; Afzal, Muhammad; Dong, Wenjing; Yaqub, Azra; Janjua, Naveed K.

    2016-06-01

    A layered structure metal oxide, LiNi0.1Fe0.90O2-δ (LNF), is explored for the advanced single layer fuel cells (SLFCs). The temperature dependent impedance profiles and concentration cells (hydrogen concentration, oxygen concentration, and H2/air atmospheres) tests prove LNF to be an intrinsically electronic conductor in air while mixed electronic and proton conductor in H2/air environment. SLFCs constructed by pure LNF materials show significant short circuiting reflected by a low device OCV and power output (175 mW cm-2 at 500 °C) due to high intrinsic electronic conduction. The power output is improved up to 640 and 760 mW cm-2, respectively at 500 and 550 °C by compositing LNF with ion conducting material, e.g., samarium doped ceria (SDC), to balance the electronic and ionic conductivity; both reached at 0.1 S cm-1 level. Such an SLFC gives super-performance and simplicity over the conventional 3-layer (anode, electrolyte and cathode) FCs, suggesting strong scientific and commercial impacts.

  3. Role of mixing on microwave-enhanced advanced oxidation process in treating sewage sludge.

    PubMed

    Kenge, Anju A; Liao, Ping H; Lo, Kwang V

    2008-10-01

    The microwave enhanced advanced oxidation process (MW/H2O2-AOP) was used for the release of nutrients and the disintegration of suspended solids from both anaerobic sludge and aerobic sludge. The purpose of this study was to determine the effects of mixing on the performance of the process, in terms of soluble ammonia, orthophosphate and soluble chemical oxygen demands. Experiments were conducted on sludge samples with various total solids concentrations (1.1-3.7%) and hydrogen peroxide dosage (1% per 1% of total solids) at 80 degrees C of microwave temperature and five minutes of heating time. The results indicated that mixing affected solids disintegration and nutrient solubilization of sewage sludge, regardless of the sludge used, anaerobic or aerobic. However, the effects of mixing on the MW/H2O2-AOP were dependent on the total solids concentration of the sludge. A paired t-test was performed on data for aerobic sludge: at 2.9% of total solids (TS), the difference for solubilization of nutrients and solids disintegration was statistically significant at a 95% confidence level between mixing and non-mixing samples. At a lower TS of 1.7% only soluble chemical oxygen demand showed significant difference between mixing and non-mixing. The results suggest that, for sludge with higher solids content, the MW/H2O2-AOP can be more effective if a mixing device is implemented.

  4. [Kinetics and mechanism analysis of the degradation of hexachlorbenzene in water by advanced oxidation process].

    PubMed

    Wei, Dong-Yang; Jia, Xiao-Shan; Lu, Gui-Ying; Liu, Guang-Li

    2008-05-01

    The degradation characteristics and rule of hexachlorobenzen (HCB) in water were studied and the results were compared by the advanced oxidation process UV, O3 and UV/O3. The experimental results showed that UV itself did not contribute to the removal of HCB obviously and HCB could be quickly degraded by O3 and UV/O3, namely UV < O3 < UV/O3. But in the case of O3 and UV/O3, raising the initial pH value of the system could not raise the removal rate of HCB, and the removal efficiency of 0.2 mg/L HCB could reach 50% within 40 min when the initial pH value was equaled to 3 and the degradation velocity could be accelerated in the acidic solution. Whether in the cases of ozone action alone or UV/O3 combined action, the degradation of HCB satisfied basically the rule of pseudo-first order reaction kinetics; and this rule was more remarkable if a constant pH value of the system was maintained. The degradation pathway and mechanism of HCB were discussed according to the measured results of the intermediated substances from the HCB degradation process by IC, GC and GC-MS.

  5. Removal of disinfection by-product precursors with ozone-UV advanced oxidation process.

    PubMed

    Chin, A; Bérubé, P R

    2005-05-01

    The efficacy of using ozone (O3), ultraviolet irradiation (UV) and the combined O3-UV advanced oxidation process (AOP) to remove 2 classes of disinfection by-product (DBP) precursors from raw surface water samples have been evaluated and compared. In particular, trihalomethane and haloacetic acids formation potentials were measured. Laboratory batch scale experiments were carried out as a function of ozone and UV dosage in order to study the removal kinetics. It is concluded that the combined O3-UV AOP is more effective than either the ozone or UV treatment alone. Ozone-UV AOP is capable of mineralizing up to 50% of the total organic carbon from the raw source water at an ozone dose of 0.62+/-0.019 mg O3/mL and a UV dose of 1.61 W s/cm2. In addition, O3-UV AOP can reduce trihalomethane formation potential by roughly 80% and haloacetic acids formation potential by roughly 70% at the same ozone and UV dosage.

  6. Measurement of hydrogen peroxide in an advanced oxidation process using an automated biosensor.

    PubMed

    Modrzejewska, B; Guwy, A J; Dinsdale, R; Hawkes, D L

    2007-01-01

    A hydrogen peroxide biosensor was used to monitor hydrogen peroxide concentrations in a UV/hydrogen peroxide immobilised Fenton advanced oxidation process (AOP). The biosensor is based on gas phase monitoring and thus is more resistant to fouling from the liquid phase constituents of industrial processes. The biosensor is supplied with catalase continually, therefore overcoming any problems with enzyme degradation, which would occur in an immobilised enzyme biosensor. The biosensors response was linear within the experimental range 30-400mg H(2)O(2)l(-1) with a R(2) correlation of 0.99. The hydrogen peroxide monitor was used to monitor residual peroxide in an AOP, operated with a step overload of hydrogen peroxide, with correlation factors of 0.96-0.99 compared to offline hydrogen peroxide determinations by UV spectroscopy. Sparging the sample with nitrogen was found to be effective in reducing the interference from dissolved gases produced with the AOP itself. It is proposed that this biosensor could be used to improve the effectiveness of AOPs via hydrogen peroxide control.

  7. Reaction kinetics of selected micropollutants in ozonation and advanced oxidation processes.

    PubMed

    Jin, Xiaohui; Peldszus, Sigrid; Huck, Peter M

    2012-12-01

    Second-order reaction rate constants of micropollutants with ozone (k(O3)) and hydroxyl radicals (k(OH)) are essential for evaluating their removal efficiencies from water during ozonation and advanced oxidation processes. Kinetic data are unavailable for many of the emerging micropollutants. Twenty-four micropollutants with very diverse structures and applications including endocrine disrupting compounds, pharmaceuticals, and personal care products were selected, and their k(O3) and k(OH) values were determined using bench-scale reactors (at pH 7 and T = 20 °C). Reactions with molecular ozone are highly selective as indicated by their k(O3) values ranging from 10(-2)-10(7) M(-1) s(-1). The general trend of ozone reactivity can be explained by micropollutant structures in conjunction with the electrophilic nature of ozone reactions. All of the studied compounds are highly reactive with hydroxyl radicals as shown by their high k(OH) values (10(8)-10(10) M(-1) s(-1)) even though they are structurally very diverse. For compounds with a low reactivity toward ozone, hydroxyl radical based treatment such as O(3)/H(2)O(2) or UV/H(2)O(2) is a viable alternative. This study contributed to filling the data gap pertaining kinetic data of organic micropollutants while confirming results reported in the literature where available. PMID:23079129

  8. Formation of disinfection by-products in the ultraviolet/chlorine advanced oxidation process.

    PubMed

    Wang, Ding; Bolton, James R; Andrews, Susan A; Hofmann, Ron

    2015-06-15

    Disinfection by-product (DBP) formation may be a concern when applying ultraviolet light and free chlorine (UV/chlorine) as an advanced oxidation process (AOP) for drinking water treatment, due to typically large chlorine doses (e.g. 5-10 mg L(-1) as free chlorine). A potential mitigating factor is the low chlorine contact times for this AOP treatment (e.g. seconds). Full-scale and pilot-scale test results showed minimal trihalomethane (THM) and haloacetic acid (HAA) formation during UV/chlorine treatment, while dichloroacetonitrile (DCAN) and bromochloroacetonitrile (BCAN) were produced rapidly. Adsorbable organic halide (AOX) formation was significant when applying the UV/chlorine process in water that had not been previously chlorinated, while little additional formation was observed in prechlorinated water. Chlorine photolysis led to chlorate and bromate formation, equivalent to approximately 2-17% and 0.01-0.05% of the photolyzed chlorine, respectively. No perchlorate or chlorite formation was observed. During simulated secondary disinfection of AOP-treated water, DBP formation potential for THMs, HAAs, HANs, and AOX was observed to increase approximately to the same extent as was observed for pretreatment using the more common AOP of UV combined with hydrogen peroxide (UV/H2O2).

  9. Using advanced oxidation treatment for biofilm inactivation by varying water vapor content in air plasma

    NASA Astrophysics Data System (ADS)

    Ryota, Suganuma; Koichi, Yasuoka

    2015-09-01

    Biofilms are caused by environmental degradation in food factories and medical facilities. The inactivation of biofilms involves making them react with chemicals including chlorine, hydrogen peroxide, and ozone, although inactivation using chemicals has a potential problem because of the hazardous properties of the residual substance and hydrogen peroxide, which have slow reaction velocity. We successfully performed an advanced oxidation process (AOP) using air plasma. Hydrogen peroxide and ozone, which were used for the formation of OH radicals in our experiment, were generated by varying the amount of water vapor supplied to the plasma. By varying the content of the water included in the air, the main product was changed from air plasma. When we increased the water content in the air, hydrogen peroxide was produced, while ozone peroxide was produced when we decreased the water content in the air. By varying the amount of water vapor, we realized a 99.9% reduction in the amount of bacteria in the biofilm when we discharged humidified air only. This work was supported by JSPS KAKENHI Grant Number 25630104.

  10. Biofilm control in water by a UV-based advanced oxidation process.

    PubMed

    Lakretz, Anat; Ron, Eliora Z; Mamane, Hadas

    2011-03-01

    An ultraviolet (UV)-based advanced oxidation process (AOP), with hydrogen peroxide and medium-pressure (MP) UV light (H(2)O(2)/UV), was used as a pretreatment strategy for biofilm control in water. Suspended Pseudomonas aeruginosa cells were exposed to UV-based AOP treatment, and the adherent biofilm formed by the surviving cells was monitored. Control experiments using H(2)O(2) or MP UV irradiation alone could inhibit biofilm formation for only short periods of time (<24 h) post-treatment. In a H(2)O(2)/filtered-UV (>295 nm) system, an additive effect on biofilm control was shown vs filtered-UV irradiation alone, probably due to activity of the added hydroxyl radical (OH•). In a H(2)O(2)/full-UV (ie full UV spectrum, not filtered) system, this result was not obtained, possibly due to the germicidal UV photons overwhelming the AOP system. Generally, however, H(2)O(2)/UV prevented biofilm formation for longer periods (days) only when maintained with residual H(2)O(2). The ratio of surviving bacterial concentration post-treatment to residual H(2)O(2) concentration played an important role in biofilm prevention and bacterial regrowth. H(2)O(2) treatments alone resulted in poorer biofilm control compared to UV-based AOP treatments maintained with similar levels of residual H(2)O(2), indicating a possible advantage of AOP.

  11. Energy efficient--advanced oxidation process for treatment of cyanide containing automobile industry wastewater.

    PubMed

    Mudliar, R; Umare, S S; Ramteke, D S; Wate, S R

    2009-05-30

    Destruction of cyanide (CN) from an automobile industry wastewater by advance oxidation process (AOP) has been evaluated. The operating conditions (in an indigenously designed photoreactor) for three different treatment strategies have been optimized. The treatment strategies involved use of, ultra violet light (UV), hydrogen peroxide (H(2)O(2)) and ozone (O(3)) in various combinations. Treatment of automobile industry wastewater (250 mg/L CN) showed fastest CN destruction, which was significantly (P<0.05) faster than that observed with synthetic wastewater (with similar CN concentration). A combined application of H(2)O(2)/O(3) was found to be the best option for maximum CN destruction. This treatment allows CN to reach the regional/international limit (of 0.02 mg/L) for safe industrial wastewater discharges to the receiving water bodies. The specific energy consumption by the photoreactor following this treatment was comparable to that obtained by conventional treatments, which use photocatalyst. Since the present treatment does not use catalyst, it provides an excellent energy efficient and economical option for treatment and safe disposal of CN containing industrial wastewater.

  12. Removal of emerging contaminants in sewage water subjected to advanced oxidation with ozone.

    PubMed

    Ibáñez, M; Gracia-Lor, E; Bijlsma, L; Morales, E; Pastor, L; Hernández, F

    2013-09-15

    Advanced oxidation processes (AOP) based on ozone treatments, assisted by ultrasounds, have been investigated at a pilot-plant scale in order to evaluate the removal of emerging contaminants in sewage water. Around 60 emerging contaminants, mainly pharmaceuticals from different therapeutically classes and drugs of abuse, have been determined in urban wastewater samples (treated and untreated) by LC-MS/MS. In a first step, the removal efficiency of these contaminants in conventional sewage water treatment plants was evaluated. Our results indicate that most of the compounds were totally or partially removed during the treatment process of influent wastewater. Up to 30 contaminants were quantified in the influent and effluent samples analysed, being antibiotics, anti-inflammatories, cholesterol lowering statin drugs and angiotensin II receptor antagonists the most frequently detected. Regarding drugs of abuse, cocaine and its metabolite benzoylecgonine were the most frequent. In a second step, the effectiveness of AOP in the removal of emerging contaminants remaining in the effluent was evaluated. Ozone treatments have been proven to be highly efficient in the removal, notably decreasing the concentrations for most of the emerging contaminants present in the water samples. The use of ultrasounds, alone or assisting ozone treatments, has been shown less effective, being practically unnecessary.

  13. The advance of non-invasive detection methods in osteoarthritis

    NASA Astrophysics Data System (ADS)

    Dai, Jiao; Chen, Yanping

    2011-06-01

    Osteoarthritis (OA) is one of the most prevalent chronic diseases which badly affected the patients' living quality and economy. Detection and evaluation technology can provide basic information for early treatment. A variety of imaging methods in OA were reviewed, such as conventional X-ray, computed tomography (CT), ultrasound (US), magnetic resonance imaging (MRI) and near-infrared spectroscopy (NIRS). Among the existing imaging modalities, the spatial resolution of X-ray is extremely high; CT is a three-dimensional method, which has high density resolution; US as an evaluation method of knee OA discriminates lesions sensitively between normal cartilage and degenerative one; as a sensitive and nonionizing method, MRI is suitable for the detection of early OA, but the cost is too expensive for routine use; NIRS is a safe, low cost modality, and is also good at detecting early stage OA. In a word, each method has its own advantages, but NIRS is provided with broader application prospect, and it is likely to be used in clinical daily routine and become the golden standard for diagnostic detection.

  14. Method for inhibiting oxidation of metal sulfide-containing material

    DOEpatents

    Elsetinow, Alicia; Borda, Michael J.; Schoonen, Martin A.; Strongin, Daniel R.

    2006-12-26

    The present invention provides means for inhibiting the oxidation of a metal sulfide-containing material, such as ore mine waste rock or metal sulfide taiulings, by coating the metal sulfide-containing material with an oxidation-inhibiting two-tail lipid coating (12) thereon, thereby inhibiting oxidation of the metal sulfide-containing material in acid mine drainage conditions. The lipids may be selected from phospholipids, sphingolipids, glycolipids and combinations thereof.

  15. Method of forming buried oxide layers in silicon

    DOEpatents

    Sadana, Devendra Kumar; Holland, Orin Wayne

    2000-01-01

    A process for forming Silicon-On-Insulator is described incorporating the steps of ion implantation of oxygen into a silicon substrate at elevated temperature, ion implanting oxygen at a temperature below 200.degree. C. at a lower dose to form an amorphous silicon layer, and annealing steps to form a mixture of defective single crystal silicon and polycrystalline silicon or polycrystalline silicon alone and then silicon oxide from the amorphous silicon layer to form a continuous silicon oxide layer below the surface of the silicon substrate to provide an isolated superficial layer of silicon. The invention overcomes the problem of buried isolated islands of silicon oxide forming a discontinuous buried oxide layer.

  16. Protein Microarrays with Novel Microfluidic Methods: Current Advances

    PubMed Central

    Dixit, Chandra K.; Aguirre, Gerson R.

    2014-01-01

    Microfluidic-based micromosaic technology has allowed the pattering of recognition elements in restricted micrometer scale areas with high precision. This controlled patterning enabled the development of highly multiplexed arrays multiple analyte detection. This arraying technology was first introduced in the beginning of 2001 and holds tremendous potential to revolutionize microarray development and analyte detection. Later, several microfluidic methods were developed for microarray application. In this review we discuss these novel methods and approaches which leverage the property of microfluidic technologies to significantly improve various physical aspects of microarray technology, such as enhanced imprinting homogeneity, stability of the immobilized biomolecules, decreasing assay times, and reduction of the costs and of the bulky instrumentation.

  17. Statistical Methods Handbook for Advanced Gas Reactor Fuel Materials

    SciTech Connect

    J. J. Einerson

    2005-05-01

    Fuel materials such as kernels, coated particles, and compacts are being manufactured for experiments simulating service in the next generation of high temperature gas reactors. These must meet predefined acceptance specifications. Many tests are performed for quality assurance, and many of these correspond to criteria that must be met with specified confidence, based on random samples. This report describes the statistical methods to be used. The properties of the tests are discussed, including the risk of false acceptance, the risk of false rejection, and the assumption of normality. Methods for calculating sample sizes are also described.

  18. Recent advances in methods and techniques for freshness quality determination and evaluation of fish and fish fillets: a review.

    PubMed

    Cheng, Jun-Hu; Sun, Da-Wen; Zeng, Xin-An; Liu, Dan

    2015-01-01

    The freshness quality of fish plays an important role in human health and the acceptance of consumers as well as in international fishery trade. Recently, with food safety becoming a critical issue of great concern in the world, determination and evaluation of fish freshness is much more significant in research and development. This review renovates and concentrates recent advances of evaluating methods for fish freshness as affected by preharvest and postharvest factors and highlights the determination methods for fish freshness including sensory evaluation, microbial inspection, chemical measurements of moisture content, volatile compounds, protein changes, lipid oxidation, and adenosine triphosphate (ATP) decomposition (K value), physical measurements, and foreign material contamination detection. Moreover, the advantages and disadvantages of these methods and techniques are compared and discussed and some viewpoints about the current work and future trends are also presented.

  19. Advanced Methods for the Solution of Differential Equations.

    ERIC Educational Resources Information Center

    Goldstein, Marvin E.; Braun, Willis H.

    This is a textbook, originally developed for scientists and engineers, which stresses the actual solutions of practical problems. Theorems are precisely stated, but the proofs are generally omitted. Sample contents include first-order equations, equations in the complex plane, irregular singular points, and numerical methods. A more recent idea,…

  20. Origins, Methods and Advances in Qualitative Meta-Synthesis

    ERIC Educational Resources Information Center

    Nye, Elizabeth; Melendez-Torres, G. J.; Bonell, Chris

    2016-01-01

    Qualitative research is a broad term encompassing many methods. Critiques of the field of qualitative research argue that while individual studies provide rich descriptions and insights, the absence of connections drawn between studies limits their usefulness. In response, qualitative meta-synthesis serves as a design to interpret and synthesise…

  1. Selenium contaminated waters: An overview of analytical methods, treatment options and recent advances in sorption methods.

    PubMed

    Santos, Sílvia; Ungureanu, Gabriela; Boaventura, Rui; Botelho, Cidália

    2015-07-15

    Selenium is an essential trace element for many organisms, including humans, but it is bioaccumulative and toxic at higher than homeostatic levels. Both selenium deficiency and toxicity are problems around the world. Mines, coal-fired power plants, oil refineries and agriculture are important examples of anthropogenic sources, generating contaminated waters and wastewaters. For reasons of human health and ecotoxicity, selenium concentration has to be controlled in drinking-water and in wastewater, as it is a potential pollutant of water bodies. This review article provides firstly a general overview about selenium distribution, sources, chemistry, toxicity and environmental impact. Analytical techniques used for Se determination and speciation and water and wastewater treatment options are reviewed. In particular, published works on adsorption as a treatment method for Se removal from aqueous solutions are critically analyzed. Recent published literature has given particular attention to the development and search for effective adsorbents, including low-cost alternative materials. Published works mostly consist in exploratory findings and laboratory-scale experiments. Binary metal oxides and LDHs (layered double hydroxides) have presented excellent adsorption capacities for selenium species. Unconventional sorbents (algae, agricultural wastes and other biomaterials), in raw or modified forms, have also led to very interesting results with the advantage of their availability and low-cost. Some directions to be considered in future works are also suggested. PMID:25847169

  2. Selenium contaminated waters: An overview of analytical methods, treatment options and recent advances in sorption methods.

    PubMed

    Santos, Sílvia; Ungureanu, Gabriela; Boaventura, Rui; Botelho, Cidália

    2015-07-15

    Selenium is an essential trace element for many organisms, including humans, but it is bioaccumulative and toxic at higher than homeostatic levels. Both selenium deficiency and toxicity are problems around the world. Mines, coal-fired power plants, oil refineries and agriculture are important examples of anthropogenic sources, generating contaminated waters and wastewaters. For reasons of human health and ecotoxicity, selenium concentration has to be controlled in drinking-water and in wastewater, as it is a potential pollutant of water bodies. This review article provides firstly a general overview about selenium distribution, sources, chemistry, toxicity and environmental impact. Analytical techniques used for Se determination and speciation and water and wastewater treatment options are reviewed. In particular, published works on adsorption as a treatment method for Se removal from aqueous solutions are critically analyzed. Recent published literature has given particular attention to the development and search for effective adsorbents, including low-cost alternative materials. Published works mostly consist in exploratory findings and laboratory-scale experiments. Binary metal oxides and LDHs (layered double hydroxides) have presented excellent adsorption capacities for selenium species. Unconventional sorbents (algae, agricultural wastes and other biomaterials), in raw or modified forms, have also led to very interesting results with the advantage of their availability and low-cost. Some directions to be considered in future works are also suggested.

  3. Protein Microarrays with Novel Microfluidic Methods: Current Advances

    PubMed Central

    Dixit, Chandra K.; Aguirre, Gerson R.

    2014-01-01

    Microfluidic-based micromosaic technology has allowed the pattering of recognition elements in restricted micrometer scale areas with high precision. This controlled patterning enabled the development of highly multiplexed arrays multiple analyte detection. This arraying technology was first introduced in the beginning of 2001 and holds tremendous potential to revolutionize microarray development and analyte detection. Later, several microfluidic methods were developed for microarray application. In this review we discuss these novel methods and approaches which leverage the property of microfluidic technologies to significantly improve various physical aspects of microarray technology, such as enhanced imprinting homogeneity, stability of the immobilized biomolecules, decreasing assay times, and reduction of the costs and of the bulky instrumentation. PMID:27600343

  4. Numerical modeling of spray combustion with an advanced VOF method

    NASA Technical Reports Server (NTRS)

    Chen, Yen-Sen; Shang, Huan-Min; Shih, Ming-Hsin; Liaw, Paul

    1995-01-01

    This paper summarizes the technical development and validation of a multiphase computational fluid dynamics (CFD) numerical method using the volume-of-fluid (VOF) model and a Lagrangian tracking model which can be employed to analyze general multiphase flow problems with free surface mechanism. The gas-liquid interface mass, momentum and energy conservation relationships are modeled by continuum surface mechanisms. A new solution method is developed such that the present VOF model can be applied for all-speed flow regimes. The objectives of the present study are to develop and verify the fractional volume-of-fluid cell partitioning approach into a predictor-corrector algorithm and to demonstrate the effectiveness of the present approach by simulating benchmark problems including laminar impinging jets, shear coaxial jet atomization and shear coaxial spray combustion flows.

  5. Advanced hybrid particulate collector and method of operation

    SciTech Connect

    Miller, Stanley J.

    2003-04-08

    A device and method for controlling particulate air pollutants of the present invention combines filtration and electrostatic collection devices. The invention includes a chamber housing a plurality of rows of filter elements. Between the rows of filter elements are rows of high voltage discharge electrodes. Between the rows of discharge electrodes and the rows of filter elements are grounded perforated plates for creating electrostatic precipitation zones.

  6. Advanced and In Situ Analytical Methods for Solar Fuel Materials.

    PubMed

    Chan, Candace K; Tüysüz, Harun; Braun, Artur; Ranjan, Chinmoy; La Mantia, Fabio; Miller, Benjamin K; Zhang, Liuxian; Crozier, Peter A; Haber, Joel A; Gregoire, John M; Park, Hyun S; Batchellor, Adam S; Trotochaud, Lena; Boettcher, Shannon W

    2016-01-01

    In situ and operando techniques can play important roles in the development of better performing photoelectrodes, photocatalysts, and electrocatalysts by helping to elucidate crucial intermediates and mechanistic steps. The development of high throughput screening methods has also accelerated the evaluation of relevant photoelectrochemical and electrochemical properties for new solar fuel materials. In this chapter, several in situ and high throughput characterization tools are discussed in detail along with their impact on our understanding of solar fuel materials.

  7. Advanced Numerical Methods and Software Approaches for Semiconductor Device Simulation

    DOE PAGES

    Carey, Graham F.; Pardhanani, A. L.; Bova, S. W.

    2000-01-01

    In this article we concisely present several modern strategies that are applicable to driftdominated carrier transport in higher-order deterministic models such as the driftdiffusion, hydrodynamic, and quantum hydrodynamic systems. The approaches include extensions of “upwind” and artificial dissipation schemes, generalization of the traditional Scharfetter – Gummel approach, Petrov – Galerkin and streamline-upwind Petrov Galerkin (SUPG), “entropy” variables, transformations, least-squares mixed methods and other stabilized Galerkin schemes such as Galerkin least squares and discontinuous Galerkin schemes. The treatment is representative rather than an exhaustive review and several schemes are mentioned only briefly with appropriate reference to the literature. Some of themore » methods have been applied to the semiconductor device problem while others are still in the early stages of development for this class of applications. We have included numerical examples from our recent research tests with some of the methods. A second aspect of the work deals with algorithms that employ unstructured grids in conjunction with adaptive refinement strategies. The full benefits of such approaches have not yet been developed in this application area and we emphasize the need for further work on analysis, data structures and software to support adaptivity. Finally, we briefly consider some aspects of software frameworks. These include dial-an-operator approaches such as that used in the industrial simulator PROPHET, and object-oriented software support such as those in the SANDIA National Laboratory framework SIERRA.« less

  8. Advanced tensile testing methods for bulk superconductors at cryogenic temperatures

    NASA Astrophysics Data System (ADS)

    Kasaba, K.; Teshima, H.; Hokari, T.; Sato, T.; Katagiri, K.; Shoji, Y.; Murakami, A.; Hirano, H.

    2006-10-01

    Tensile tests of bulk high Tc superconductors at room temperature have been generally performed by gluing the bulk specimens to Al-alloy rods. Because of the difference in the coefficient of thermal expansion, thermal stresses were induced at cryogenic temperatures especially near the interface between the specimen and the rods. In this study, tensile testing methods with minimized effect of the thermal stress were tried by using specimens cut from Dy-Ba-Cu-O superconductors. These were: (1) The rod material of Al-alloy was replaced with Ti-alloy, which has the coefficient close to the bulk. (2) The interlayer made of the identical bulk superconductor was inserted between the specimen and the Ti-alloy rod. The nominal tensile strength at the liquid nitrogen temperature (LNT) of the specimen glued to the Ti-alloy rods was significantly higher than that glued to the Al-alloy rods. The application of the interlayers increased the strength significantly. The FEM analysis showed that the thermal tensile stress component in the direction of loading axis within the specimen at LNT is markedly reduced by the method (1) and substantially eliminated in the method (2).

  9. Evaluation of pediatric manual wheelchair mobility using advanced biomechanical methods.

    PubMed

    Slavens, Brooke A; Schnorenberg, Alyssa J; Aurit, Christine M; Graf, Adam; Krzak, Joseph J; Reiners, Kathryn; Vogel, Lawrence C; Harris, Gerald F

    2015-01-01

    There is minimal research of upper extremity joint dynamics during pediatric wheelchair mobility despite the large number of children using manual wheelchairs. Special concern arises with the pediatric population, particularly in regard to the longer duration of wheelchair use, joint integrity, participation and community integration, and transitional care into adulthood. This study seeks to provide evaluation methods for characterizing the biomechanics of wheelchair use by children with spinal cord injury (SCI). Twelve subjects with SCI underwent motion analysis while they propelled their wheelchair at a self-selected speed and propulsion pattern. Upper extremity joint kinematics, forces, and moments were computed using inverse dynamics methods with our custom model. The glenohumeral joint displayed the largest average range of motion (ROM) at 47.1° in the sagittal plane and the largest average superiorly and anteriorly directed joint forces of 6.1% BW and 6.5% BW, respectively. The largest joint moments were 1.4% body weight times height (BW × H) of elbow flexion and 1.2% BW × H of glenohumeral joint extension. Pediatric manual wheelchair users demonstrating these high joint demands may be at risk for pain and upper limb injuries. These evaluation methods may be a useful tool for clinicians and therapists for pediatric wheelchair prescription and training. PMID:25802860

  10. Evaluation of pediatric manual wheelchair mobility using advanced biomechanical methods.

    PubMed

    Slavens, Brooke A; Schnorenberg, Alyssa J; Aurit, Christine M; Graf, Adam; Krzak, Joseph J; Reiners, Kathryn; Vogel, Lawrence C; Harris, Gerald F

    2015-01-01

    There is minimal research of upper extremity joint dynamics during pediatric wheelchair mobility despite the large number of children using manual wheelchairs. Special concern arises with the pediatric population, particularly in regard to the longer duration of wheelchair use, joint integrity, participation and community integration, and transitional care into adulthood. This study seeks to provide evaluation methods for characterizing the biomechanics of wheelchair use by children with spinal cord injury (SCI). Twelve subjects with SCI underwent motion analysis while they propelled their wheelchair at a self-selected speed and propulsion pattern. Upper extremity joint kinematics, forces, and moments were computed using inverse dynamics methods with our custom model. The glenohumeral joint displayed the largest average range of motion (ROM) at 47.1° in the sagittal plane and the largest average superiorly and anteriorly directed joint forces of 6.1% BW and 6.5% BW, respectively. The largest joint moments were 1.4% body weight times height (BW × H) of elbow flexion and 1.2% BW × H of glenohumeral joint extension. Pediatric manual wheelchair users demonstrating these high joint demands may be at risk for pain and upper limb injuries. These evaluation methods may be a useful tool for clinicians and therapists for pediatric wheelchair prescription and training.

  11. Evaluation of Pediatric Manual Wheelchair Mobility Using Advanced Biomechanical Methods

    PubMed Central

    Slavens, Brooke A.; Schnorenberg, Alyssa J.; Aurit, Christine M.; Graf, Adam; Krzak, Joseph J.; Reiners, Kathryn; Vogel, Lawrence C.; Harris, Gerald F.

    2015-01-01

    There is minimal research of upper extremity joint dynamics during pediatric wheelchair mobility despite the large number of children using manual wheelchairs. Special concern arises with the pediatric population, particularly in regard to the longer duration of wheelchair use, joint integrity, participation and community integration, and transitional care into adulthood. This study seeks to provide evaluation methods for characterizing the biomechanics of wheelchair use by children with spinal cord injury (SCI). Twelve subjects with SCI underwent motion analysis while they propelled their wheelchair at a self-selected speed and propulsion pattern. Upper extremity joint kinematics, forces, and moments were computed using inverse dynamics methods with our custom model. The glenohumeral joint displayed the largest average range of motion (ROM) at 47.1° in the sagittal plane and the largest average superiorly and anteriorly directed joint forces of 6.1% BW and 6.5% BW, respectively. The largest joint moments were 1.4% body weight times height (BW × H) of elbow flexion and 1.2% BW × H of glenohumeral joint extension. Pediatric manual wheelchair users demonstrating these high joint demands may be at risk for pain and upper limb injuries. These evaluation methods may be a useful tool for clinicians and therapists for pediatric wheelchair prescription and training. PMID:25802860

  12. Advanced numerical methods and software approaches for semiconductor device simulation

    SciTech Connect

    CAREY,GRAHAM F.; PARDHANANI,A.L.; BOVA,STEVEN W.

    2000-03-23

    In this article the authors concisely present several modern strategies that are applicable to drift-dominated carrier transport in higher-order deterministic models such as the drift-diffusion, hydrodynamic, and quantum hydrodynamic systems. The approaches include extensions of upwind and artificial dissipation schemes, generalization of the traditional Scharfetter-Gummel approach, Petrov-Galerkin and streamline-upwind Petrov Galerkin (SUPG), entropy variables, transformations, least-squares mixed methods and other stabilized Galerkin schemes such as Galerkin least squares and discontinuous Galerkin schemes. The treatment is representative rather than an exhaustive review and several schemes are mentioned only briefly with appropriate reference to the literature. Some of the methods have been applied to the semiconductor device problem while others are still in the early stages of development for this class of applications. They have included numerical examples from the recent research tests with some of the methods. A second aspect of the work deals with algorithms that employ unstructured grids in conjunction with adaptive refinement strategies. The full benefits of such approaches have not yet been developed in this application area and they emphasize the need for further work on analysis, data structures and software to support adaptivity. Finally, they briefly consider some aspects of software frameworks. These include dial-an-operator approaches such as that used in the industrial simulator PROPHET, and object-oriented software support such as those in the SANDIA National Laboratory framework SIERRA.

  13. Reduction of organic trace compounds and fresh water consumption by recovery of advanced oxidation processes treated industrial wastewater.

    PubMed

    Bierbaum, S; Öller, H-J; Kersten, A; Klemenčič, A Krivograd

    2014-01-01

    Ozone (O(3)) has been used successfully in advanced wastewater treatment in paper mills, other sectors and municipalities. To solve the water problems of regions lacking fresh water, wastewater treated by advanced oxidation processes (AOPs) can substitute fresh water in highly water-consuming industries. Results of this study have shown that paper strength properties are not impaired and whiteness is slightly impaired only when reusing paper mill wastewater. Furthermore, organic trace compounds are becoming an issue in the German paper industry. The results of this study have shown that AOPs are capable of improving wastewater quality by reducing organic load, colour and organic trace compounds.

  14. Polycrystalline ferroelectric or multiferroic oxide articles on biaxially textured substrates and methods for making same

    DOEpatents

    Goyal, Amit; Shin, Junsoo

    2015-03-31

    A polycrystalline ferroelectric and/or multiferroic oxide article includes a substrate having a biaxially textured surface; at least one biaxially textured buffer layer supported by the substrate; and a biaxially textured ferroelectric or multiferroic oxide layer supported by the buffer layer. Methods for making polycrystalline ferroelectric and/or multiferroic oxide articles are also disclosed.

  15. A novel nanostructure of cadmium oxide synthesized by mechanochemical method

    SciTech Connect

    Tadjarodi, A.; Imani, M.

    2011-11-15

    Highlights: {yields} A novel nanostructure of CdO was synthesized by mechanochemical reaction followed by calcination. {yields} Mechanochemical method is a simple and low-cost to synthesize nanomaterials. {yields} The obtained precursor was characterized by FT-IR, NMR techniques and elemental analysis. {yields} SEM images showed cauliflower-like shape of sample with components average diameter of 68 nm. {yields} The rods and tubes bundles with single crystalline nature were revealed by ED pattern and TEM images. -- Abstract: Cauliflower-like cadmium oxide (CdO) nanostructure was synthesized by mechanochemical reaction followed calcination procedure. Cadmium acetate dihydrate and acetamide were used as reagents and the resulting precursor was calcinated at 450 {sup o}C for 2 h in air. The structures of the precursor and resultant product of the heating treatment were characterized using Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and elemental analysis, X-ray powder diffraction (XRD), energy-dispersive X-ray spectroscopy analysis (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electron diffraction pattern (ED). SEM and TEM images revealed the cauliflower-like morphology of the sample. This structure includes the bundles of rods and tubes in nanoscale, which combine with each other and form the resulting morphology with the average diameter, 68 nm of the components. ED pattern indicated the single crystal nature of the formed bundles.

  16. Evaluation of Ischemia-Modified Albumin, Malondialdehyde, and Advanced Oxidative Protein Products as Markers of Vascular Injury in Diabetic Nephropathy

    PubMed Central

    Ahmad, Afzal; Manjrekar, Poornima; Yadav, Charu; Agarwal, Ashish; Srikantiah, Rukmini Mysore; Hegde, Anupama

    2016-01-01

    AIM This study aimed at evaluation of ischemia-modified albumin (IMA), malondialdehyde (MDA), and advanced oxidative protein products (AOPP) as markers of vascular injury in diabetic nephropathy (DN) with derivation of cutoff values for the same. MATERIALS AND METHODS Study population comprised 60 diabetes patients and 30 controls, with diabetes patients further categorized into three groups based on urine albumin/creatinine ratio (UACR) of <30 mg/g (diabetes without microalbuminuria), 30–300 mg/g (early DN), and >300 mg/g of creatinine (overt DN). Serum IMA, MDA, and AOPP were estimated by enzyme-linked immunosorbent assay; HbA1c, serum creatinine, urine albumin, and urine creatinine were estimated using automated analyzers. Statistical analysis was done using analysis of variance, Pearson’s correlation coefficient, and receiver-operating characteristic curve. RESULTS A statistically significant difference was found in the levels of IMA among patients with early DN (154 ng/mL), diabetes without nephropathy (109.4 ng/mL), and healthy controls (45.7 ng/mL), with highest levels in early DN cases. Similar increase was seen in AOPP as well. A significant correlation was observed between IMA and UACR in diabetes without nephropathy (r = 0.448). CONCLUSION The present study postulates serum IMA as a novel biomarker for the assessment of disease progression in diabetes even before microalbuminuria, and a cutoff point ≥99 ng/mL can be used for detection of early DN. PMID:27158221

  17. Long length oxide template for YBCO coated conductor prepared by surface-oxidation epitaxy method

    NASA Astrophysics Data System (ADS)

    Watanabe, Tomonori; Matsumoto, Kaname; Maeda, Toshihiko; Tanigawa, Toru; Hirabayashi, Izumi

    2001-08-01

    A 50 m long, biaxially textured NiO buffer layer for epitaxial growth ofYBa 2Cu 3O 7- δ (YBCO) film has been fabricated on the long cube textured nickel tape using surface-oxidation epitaxy (SOE) method. The SOE-NiO layers were highly {1 0 0} <0 0 1> textured. The full width at half maximum of 10-14.5° from X-ray φ-scan ( Δφ) was in the range of 10-14.5° through the whole length. The critical current density ( Jc) values exceeding 0.3 MA/cm 2 (77 K, 0 T) have been obtained in short samples of YBCO films on NiO/Ni tapes, by using thin MgO cap layer. Thirty meters long Ni-clad Ni-20wt.%Cr (Ni/NiCr) and Ni-clad austenitic stainless steel (Ni/SS) tapes were also prepared for YBCO coated conductors with higher strength and lower magnetism than those of pure nickel tape. Highly {1 0 0} <0 0 1> textured NiO layers were formed on those textured composite tapes by SOE method as same as on cube textured pure nickel tapes. YBCO films with Jc of 0.1 MA/cm 2 (77 K, 0 T) have been obtained on MgO/SOE-NiO layer of short Ni/NiCr composite tape.

  18. Use of Advanced Oxidation and Aerobic Degradation for Remediation of Various Hydrocarbon Contaminates

    SciTech Connect

    Paul Fallgren

    2009-03-06

    Western Research Institute in conjunction with Sierra West Consultants, Inc., Tetra Tech, Inc., and the U.S. Department of Energy conducted laboratory and field studies to test different approaches to enhance degradation of hydrocarbons and associated contaminants. WRI in conjunction with Sierra West Consultants, Inc., conducted a laboratory and field study for using ozone to treat a site contaminated with MTBE and other hydrocarbons. Results from this study demonstrate that a TOD test can be used to resolve the O{sub 3} dosage problem by establishing a site-specific benchmark dosage for field ozone applications. The follow-up testing of the laboratory samples provided indications that intrinsic biodegradation could be stimulated by adding oxygen. Laboratory studies also suggests that O3 dosage in the full-scale field implementation could be dialed lower than stoichiometrically designed to eliminate the formation of Cr(VI). WRI conducted a study involving a series of different ISCO oxidant applications to diesel-contaminated soil and determined the effects on enhancing biodegradation to degrade the residual hydrocarbons. Soils treated with permanganate followed by nutrients and with persulfate followed by nutrients resulted in the largest decrease in TPH. The possible intermediates and conditions formed from NOM and TPH oxidation by permanganate and activated persulfate favors microbial TPH degrading activity. A 'passive-oxidation' method using microbial fuel cell (MFC) technology was conducted by WRI in conjunction with Tetra Tech, Inc., to degrade MTBE in groundwater. These experiments have demonstrated that a working MFC (i.e., one generating power) could be established in the laboratory using contaminated site water or buffered media inoculated with site water and spiked with MTBE, benzene, or toluene. Electrochemical methods were studied by WRI with goal of utilizing low voltage and amperage electrical sources for 'geo-oxidation' of organic contaminants. The

  19. Advanced hybrid particulate collector and method of operation

    DOEpatents

    Miller, S.J.

    1999-08-17

    A device and method for controlling particulate air pollutants of the present invention combines filtration and electrostatic collection devices. The invention includes a chamber housing a plurality of rows of filter elements. Between each row of filter elements is a grounded plate. Between the grounded plates and the filter elements are electrode grids for creating electrostatic precipitation zones between each row of filter elements. In this way, when the filter elements are cleaned by pulsing air in a reverse direction, the dust removed from the bags will collect in the electrostatic precipitation zones rather than on adjacent filter elements. 12 figs.

  20. Advanced hybrid particulate collector and method of operation

    DOEpatents

    Miller, Stanley J.

    1999-01-01

    A device and method for controlling particulate air pollutants of the present invention combines filtration and electrostatic collection devices. The invention includes a chamber housing a plurality of rows of filter elements. Between each row of filter elements is a grounded plate. Between the grounded plates and the filter elements are electrode grids for creating electrostatic precipitation zones between each row of filter elements. In this way, when the filter elements are cleaned by pulsing air in a reverse direction, the dust removed from the bags will collect in the electrostatic precipitation zones rather than on adjacent filter elements.

  1. Advanced Signal Processing Methods Applied to Digital Mammography

    NASA Technical Reports Server (NTRS)

    Stauduhar, Richard P.

    1997-01-01

    The work reported here is on the extension of the earlier proposal of the same title, August 1994-June 1996. The report for that work is also being submitted. The work reported there forms the foundation for this work from January 1997 to September 1997. After the earlier work was completed there were a few items that needed to be completed prior to submission of a new and more comprehensive proposal for further research. Those tasks have been completed and two new proposals have been submitted, one to NASA, and one to Health & Human Services WS). The main purpose of this extension was to refine some of the techniques that lead to automatic large scale evaluation of full mammograms. Progress on each of the proposed tasks follows. Task 1: A multiresolution segmentation of background from breast has been developed and tested. The method is based on the different noise characteristics of the two different fields. The breast field has more power in the lower octaves and the off-breast field behaves similar to a wideband process, where more power is in the high frequency octaves. After the two fields are separated by lowpass filtering, a region labeling routine is used to find the largest contiguous region, the breast. Task 2: A wavelet expansion that can decompose the image without zero padding has been developed. The method preserves all properties of the power-of-two wavelet transform and does not add appreciably to computation time or storage. This work is essential for analysis of the full mammogram, as opposed to selecting sections from the full mammogram. Task 3: A clustering method has been developed based on a simple counting mechanism. No ROC analysis has been performed (and was not proposed), so we cannot finally evaluate this work without further support. Task 4: Further testing of the filter reveals that different wavelet bases do yield slightly different qualitative results. We cannot provide quantitative conclusions about this for all possible bases

  2. Advanced methods for displays and remote control of robots.

    PubMed

    Eliav, Ami; Lavie, Talia; Parmet, Yisrael; Stern, Helman; Edan, Yael

    2011-11-01

    An in-depth evaluation of the usability and situation awareness performance of different displays and destination controls of robots are presented. In two experiments we evaluate the way information is presented to the operator and assess different means for controlling the robot. Our study compares three types of displays: a "blocks" display, a HUD (head-up display), and a radar display, and two types of controls: touch screen and hand gestures. The HUD demonstrated better performance when compared to the blocks display and was perceived to have greater usability compared to the radar display. The HUD was also found to be more useful when the operation of the robot was more difficult, i.e., when using the hand-gesture method. The experiments also pointed to the importance of using a wide viewing angle to minimize distortion and for easier coping with the difficulties of locating objects in the field of view margins. The touch screen was found to be superior in terms of both objective performance and its perceived usability. No differences were found between the displays and the controllers in terms of situation awareness. This research sheds light on the preferred display type and controlling method for operating robots from a distance, making it easier to cope with the challenges of operating such systems.

  3. Recent advances in computer camera methods for machine vision

    NASA Astrophysics Data System (ADS)

    Olson, Gaylord G.; Walker, Jo N.

    1998-10-01

    During the past year, several new computer camera methods (hardware and software) have been developed which have applications in machine vision. These are described below, along with some test results. The improvements are generally in the direction of higher speed and greater parallelism. A PCI interface card has been designed which is adaptable to multiple CCD types, both color and monochrome. A newly designed A/D converter allows for a choice of 8 or 10-bit conversion resolution and a choice of two different analog inputs. Thus, by using four of these converters feeding the 32-bit PCI data bus, up to 8 camera heads can be used with a single PCI card, and four camera heads can be operated in parallel. The card has been designed so that any of 8 different CCD types can be used with it (6 monochrome and 2 color CCDs) ranging in resolution from 192 by 165 pixels up to 1134 by 972 pixels. In the area of software, a method has been developed to better utilize the decision-making capability of the computer along with the sub-array scan capabilities of many CCDs. Specifically, it is shown below how to achieve a dual scan mode camera system wherein one scan mode is a low density, high speed scan of a complete image area, and a higher density sub-array scan is used in those areas where changes have been observed. The name given to this technique is adaptive sub-array scanning.

  4. Method of producing homogeneous mixed metal oxides and metal-metal oxide mixtures

    DOEpatents

    Quinby, Thomas C.

    1978-01-01

    Metal powders, metal oxide powders, and mixtures thereof of controlled particle size are provided by reacting an aqueous solution containing dissolved metal values with excess urea. Upon heating, urea reacts with water from the solution leaving a molten urea solution containing the metal values. The molten urea solution is heated to above about 180.degree. C. whereupon metal values precipitate homogeneously as a powder. The powder is reduced to metal or calcined to form oxide particles. One or more metal oxides in a mixture can be selectively reduced to produce metal particles or a mixture of metal and metal oxide particles.

  5. Method of Suppressing Sublimation in Advanced Thermoelectric Devices

    NASA Technical Reports Server (NTRS)

    Sakamoto, Jeffrey S. (Inventor); Caillat, Thierry (Inventor); Fleurial, Jean-Pierre (Inventor); Snyder, G. Jeffrey (Inventor)

    2009-01-01

    A method of applying a physical barrier to suppress thermal decomposition near a surface of a thermoelectric material including applying a continuous metal foil to a predetermined portion of the surface of the thermoelectric material, physically binding the continuous metal foil to the surface of the thermoelectric material using a binding member, and heating in a predetermined atmosphere the applied and physically bound continuous metal foil and the thermoelectric material to a sufficient temperature in order to promote bonding between the continuous metal foil and the surface of the thermoelectric material. The continuous metal foil forms a physical barrier to enclose a predetermined portion of the surface. Thermal decomposition is suppressed at the surface of the thermoelectric material enclosed by the physical barrier when the thermoelectric element is in operation.

  6. Comparative Assessment of Advanced Gay Hydrate Production Methods

    SciTech Connect

    M. D. White; B. P. McGrail; S. K. Wurstner

    2009-06-30

    Displacing natural gas and petroleum with carbon dioxide is a proven technology for producing conventional geologic hydrocarbon reservoirs, and producing additional yields from abandoned or partially produced petroleum reservoirs. Extending this concept to natural gas hydrate production offers the potential to enhance gas hydrate recovery with concomitant permanent geologic sequestration. Numerical simulation was used to assess a suite of carbon dioxide injection techniques for producing gas hydrates from a variety of geologic deposit types. Secondary hydrate formation was found to inhibit contact of the injected CO{sub 2} regardless of injectate phase state, thus diminishing the exchange rate due to pore clogging and hydrate zone bypass of the injected fluids. Additional work is needed to develop methods of artificially introducing high-permeability pathways in gas hydrate zones if injection of CO{sub 2} in either gas, liquid, or micro-emulsion form is to be more effective in enhancing gas hydrate production rates.

  7. Advances in Isolation Methods for Spermatogonial Stem Cells.

    PubMed

    Zhang, Rui; Sun, Jin; Zou, Kang

    2016-02-01

    Stem cell research has led to many remarkable achievements in recent years, but progress in the study of spermatogonial stem cells (SSCs) has been relatively slow, partly due to the slow development of techniques for spermatogonial stem cell isolation. The major accomplishments of SSC sorting and identification occurred approximately 10 years ago, and since that time, these techniques have been widely used without major improvements. In this article, we briefly introduce the biological properties of SSCs before reviewing the development of sorting techniques for SSCs in the past decades. We then summarize recent achievements in SSC sorting and finally discuss the advantages and disadvantages of SSC isolation methods, to provide new insight into techniques and research related to spermatogonial stem cells and promote the development of reproductive biology.

  8. Processing Methods Established To Fabricate Porous Oxide Ceramic Spheres for Thermal Barrier Coating Applications

    NASA Technical Reports Server (NTRS)

    Dynys, Frederick W.

    2003-01-01

    As gas turbine technology advances, the demand for efficient engines and emission reduction requires a further increase in operating temperatures, but combustion temperatures are currently limited by the temperature capability of the engine components. The existing thermal barrier coating (TBC) technology does not provide sufficient thermal load reduction at a 3000 F (1649 C) operating condition. Advancement in thermal barrier coating technology is needed to meet this aggressive goal. One concept for improving thermal barrier coating effectiveness is to design coating systems that incorporate a layer that reflects or scatters photon radiation. This can be achieved by using porous structures. The refractive index mismatch between the solid and pore, the pore size, and the pore density can be engineered to efficiently scatter photon radiation. Under NASA s Ultra-Efficient Engine Technology (UEET) Program, processing methods to fabricate porous ceramic spheres suitable for scattering photon radiation at elevated temperatures have been established. A straightforward templating process was developed at the NASA Glenn Research Center that requires no special processing equipment. The template was used to define particle shape, particle size, and pore size. Spherical organic cation exchange resins were used as a structure-directing template. The cation exchange resins have dual template capabilities that can produce different pore architectures. This process can be used to fabricate both metal oxide and metal carbide spheres.

  9. Advanced hydraulic fracturing methods to create in situ reactive barriers

    SciTech Connect

    Murdoch, L. |; Siegrist, B.; Vesper, S.

    1997-12-31

    Many contaminated areas consist of a source area and a plume. In the source area, the contaminant moves vertically downward from a release point through the vadose zone to an underlying saturated region. Where contaminants are organic liquids, NAPL may accumulate on the water table, or it may continue to migrate downward through the saturated region. Early developments of permeable barrier technology have focused on intercepting horizontally moving plumes with vertical structures, such as trenches, filled with reactive material capable of immobilizing or degrading dissolved contaminants. This focus resulted in part from a need to economically treat the potentially large volumes of contaminated water in a plume, and in part from the availability of construction technology to create the vertical structures that could house reactive compounds. Contaminant source areas, however, have thus far remained largely excluded from the application of permeable barrier technology. One reason for this is the lack of conventional construction methods for creating suitable horizontal structures that would place reactive materials in the path of downward-moving contaminants. Methods of hydraulic fracturing have been widely used to create flat-lying to gently dipping layers of granular material in unconsolidated sediments. Most applications thus far have involved filling fractures with coarse-grained sand to create permeable layers that will increase the discharge of wells recovering contaminated water or vapor. However, it is possible to fill fractures with other compounds that alter the chemical composition of the subsurface. One early application involved development and field testing micro-encapsulated sodium percarbonate, a solid compound that releases oxygen and can create aerobic conditions suitable for biodegradation in the subsurface for several months.

  10. Wet Oxidation as a Waste Treatment Method in Closed Systems

    NASA Technical Reports Server (NTRS)

    Onisko, B. L.; Wydeven, T.

    1982-01-01

    The chemistry of the wet oxidation process was investigated in relation to production of plant nutrients from plant and human waste materials as required for a closed life support system. Hydroponically grown lettuce plants were used as a model plant waste, and oxygen gas was used as an oxidant. Organic nitrogen content was decreased 88-100%, depending on feed material. Production of ammonia and nitrogen gas accounted for all of the observed decrease in organic nitrogen content. No nitrous oxide (N2O) was detected. The implications of these results for closed life support systems are discussed.

  11. An evolutionary method for synthesizing technological planning and architectural advance

    NASA Astrophysics Data System (ADS)

    Cole, Bjorn Forstrom

    In the development of systems with ever-increasing performance and/or decreasing drawbacks, there inevitably comes a point where more progress is available by shifting to a new set of principles of use. This shift marks a change in architecture, such as between the piston-driven propeller and the jet engine. The shift also often involves an abandonment of previous competencies that have been developed with great effort, and so a foreknowledge of these shifts can be advantageous. A further motivation for this work is the consideration of the Micro Autonomous Systems and Technology (MAST) project, which aims to develop very small (<5 cm) robots for a variety of uses. This is primarily a technology research project, and there is no baseline morphology for a robot to be considered. This then motivates an interest in the ability to automatically compose physical architectures from a series of components and quantitatively analyze them for a basic, conceptual analysis. The ability to do this would enable researchers to turn attention to the most promising forms. This work presents a method for using technology forecasts of components that enable future architectural shifts in order to forecast those shifts. The method consists of the use of multidimensional S-curves, genetic algorithms, and a graph-based formulation of architecture that is more flexible than other morphological techniques. Potential genetic operators are explored in depth to draft a final graph-based genetic algorithm. This algorithm is then implemented in a design code called Sindri, which leverages a commercial design tool named Pacelab. The first chapters of this thesis provide context and a philosophical background to the studies and research that was conducted. In particular, the idea that technology progresses in a fundamentally gradual way is developed and supported with previous historical research. The import of this is that the future can to some degree be predicted by the past, provided that

  12. History of Resistance Welding Oxide Dispersion Strengthened Cladding and other High Temperature Materials at Center for Advanced Energy Studies

    SciTech Connect

    Larry Zirker; Nathan Jerred; Dr. Indrajit Charit; James Cole

    2012-03-01

    Research proposal 08-1079, 'A Comparative Study of Welded ODS Cladding Materials for AFCI/GNEP,' was funded in 2008 under an Advanced Fuel Cycle Initiative (AFCI) Research and Development Funding Opportunity, number DE-PS07-08ID14906. Th proposal sought to conduct research on joining oxide dispersion strengthen (ODS) tubing material to a solid end plug. This document summarizes the scientific and technical progress achieved during the project, which ran from 2008 to 2011.

  13. Effects of advanced oxidation on green sand properties via iron casting into green sand molds.

    PubMed

    Wang, Yujue; Cannon, Fred S; Voigt, Robert C; Komarneni, Sridhar; Furness, J C

    2006-05-01

    The effects of advanced oxidation (AO) processing on the properties of green sand were studied via pouring cast iron into green sand molds. Upon cooling, the green sand molds were autopsied at various distances from the metal-sand interface. Autopsy green sand samples collected from a mold that incorporated AO water were characterized and compared to controlled samples collected from a similar autopsied mold made with conventional tap water (TAP). It was found that the AO processing removed a coating of coal pyrolysis products from the clay surface that typically accumulated on the clay surface. As a result, the AO-conditioned green sand retained 10-15% more active clay as measured bythe standard ultrasonic methylene blue titration than did the TAP-conditioned green sand. The AO processing also nearly doubled the generation of activated carbon from the normalized amount of coal composition of the green sand during the casting process. The AO-enhanced activated carbon generation and the AO-incurred clay surface cleaning provided the AO-conditioned green sand with higher normalized pore volume, and thus higher normalized m-xylene adsorption capacity, i.e., relative to before-metal-pouring conditions. Furthermore, mathematical analysis indicated that the AO-conditioned green sand better retained its important properties after pouring than did the TAP-conditioned green sand. Effectively, this meant after metal pouring, the AO-conditioned sample offered about the same net properties as the TAP-conditioned sample, even though the AO-conditioned sample contained less clay and coal before metal pouring. These results conformed to the full-scale foundry empirical finding that when AO is used, foundries need less makeup clay and coal addition through each casting cycle, and they release less air emissions. PMID:16719117

  14. Re-engineering an artificial sweetener: transforming sucralose residuals in water via advanced oxidation.

    PubMed

    Keen, Olya S; Linden, Karl G

    2013-07-01

    Sucralose is an artificial sweetener persistently present in wastewater treatment plant effluents and aquatic environments impacted by human activity. It has a potential to accumulate in the water cycle due to its resistance to common water and wastewater treatment processes. This study examined UV/H2O2 advanced oxidation and found that hydroxyl substitution of the chlorine atoms on the sucralose molecule can form a carbohydrate consisting of fructose and sugar alcohol, very similar to environmentally benign sucrose. The second-order reaction rate constant for loss of parent molecule via reaction with hydroxyl radical was determined to be (1.56 ± 0.03)·10(9) M(-1)s(-1). The degradation pathway involves substitution of a single chlorine by a hydroxyl group, with cyclic moiety being a preferential site for initial dechlorination. Further reaction leads to full dechlorination of the molecule, presumably via hydroxyl group substitution as well. No direct photolysis by UV wavelengths above 200 nm was observed. Because of its photostability when exposed to UV wavelengths ≥200 nm, known stability with ozone, limits of quantification by mass spectrometry close to or below environmental concentrations (<5 μg/L) without preconcentration, and otherwise stable nature, sucralose can be used as an in situ hydroxyl radical probe for UV-based and ozone-based AOP processes. As a compound safe for human consumption, sucralose makes a suitable full scale hydroxyl radical probe fit even for drinking water treatment plant applications. Its main drawback as a probe is lack of UV detection and as a result a need for mass spectrometry analysis. PMID:23410009

  15. Incorporating biodegradation and advanced oxidation processes in the treatment of spent metalworking fluids.

    PubMed

    MacAdam, Jitka; Ozgencil, Haci; Autin, Olivier; Pidou, Marc; Temple, Clive; Parsons, Simon; Jefferson, Bruce

    2012-12-01

    The treatment of spent metalworking fluids (MWFs) is difficult due to their complex and variable composition. Small businesses often struggle to meet increasingly stringent legislation and rising costs as they need to treat this wastewater on site annually over a short period. Larger businesses that treat their wastewater continuously can benefit from the use of biological processes, although new MWFs designed to resist biological activity represent a challenge. A three-stage treatment is generally applied, with the oil phase being removed first, followed by a reduction in COD loading and then polishing of the effluent's quality in the final stage. The performance of advanced oxidation processes (AOPs), which could be of benefit to both types of businesses was studied. After assessing the biodegradability of spent MFW, different AOPs were used (UV/H2O2, photo-Fenton and UV/TiO2) to establish the treatability of this wastewater by hydroxyl radicals (*OH). The interactions of both the chemical and biological treatments were also investigated. The wastewater was found to be readily biodegradable in the Zahn-Wellens test with 69% COD and 74% DOC removal. The UV/TiO2 reactor was found to be the cheapest option achieving a very good COD removal (82% at 20 min retention time and 10 L min(-1) aeration rate). The photo-Fenton process was found to be efficient in terms of degradation rate, achieving 84% COD removal (1 M Fe2+, 40 M H2O2, 20.7 J cm(-2), pH 3) and also improving the wastewater's biodegradability. The UV/H202 process was the most effective in removing recalcitrant COD in the post-biological treatment stage. PMID:23437675

  16. Oxidized low-density lipoprotein is associated with advanced-stage prostate cancer.

    PubMed

    Wan, Fangning; Qin, Xiaojian; Zhang, Guiming; Lu, Xiaolin; Zhu, Yao; Zhang, Hailiang; Dai, Bo; Shi, Guohai; Ye, Dingwei

    2015-05-01

    Clinical and epidemiological data suggest coronary artery disease shares etiology with prostate cancer (PCa). The aim of this work was to assess the effects of several serum markers reported in cardiovascular disease on PCa. Serum markers (oxidized low-density lipoprotein [ox-LDL], apolipoprotein [apo] B100, and apoB48) in peripheral blood samples from 50 patients from Fudan University Shanghai Cancer Center (FUSCC) with localized or lymph node metastatic PCa were investigated in this study. Twenty-five samples from normal individuals were set as controls. We first conducted enzyme-linked immunosorbent assay analysis to select candidate markers that were significantly different between these patients and controls. Then, the clinical relevance between OLR1 (the ox-LDL receptor) expression and PCa was analyzed in The Cancer Genome Atlas (TCGA) cohort. We also investigated the function of ox-LDL in PCa cell lines in vitro. Phosphorylation protein chips were used to analyze cell signaling pathways in ox-LDL-treated PC-3 cells. The ox-LDL level was found to be significantly correlated with N stage of prostate cancer. OLR1 expression was correlated with lymph node metastasis in the TCGA cohort. In vitro, ox-LDL stimulated the proliferation, migration, and invasion of LNCaP and PC-3 in a dose-dependent manner. The results of phosphoprotein microarray illustrated that ox-LDL could influence multiple signaling pathways of PC-3. Activation of proliferation promoting signaling pathways (including β-catenin, cMyc, NF-κB, STAT1, STAT3) as well as apoptosis-associating signaling pathways (including p27, caspase-3) demonstrated that ox-LDL had complicated effects on prostate cancer. Increased serum ox-LDL level and OLR1 expression may indicate advanced-stage PCa and lymph node metastasis. Moreover, ox-LDL could stimulate PCa proliferation, migration, and invasion in vitro.

  17. Transformation of polyfluorinated compounds in natural waters by advanced oxidation processes.

    PubMed

    Anumol, Tarun; Dagnino, Sonia; Vandervort, Darcy R; Snyder, Shane A

    2016-02-01

    The presence of perfluorocarboxylic acids (PFCAs) in source and finished drinking waters is a concern with studies showing bioaccumulation and adverse toxicological effects in wildlife and potentially humans. Per/Polyfluoroalkyl substances (PFAS) such as fluorotelomer alcohols have been identified as precursors for PFCAs in biological pathways. In this study, we investigated the fate of 6:2 and 8:2 homologues of the fluorotelomer unsaturated carboxylic acids (FTUCAs) during advanced oxidation process (AOPs). Results showed 6:2 FTUCA and 8:2 FTUCA transformed into 6-C PFCA (PFHxA) and 8-C PFCA (PFOA) respectively with very little other PFCA formation for all AOPs. The degradation of 6:2 FTUCA and 8:2 FTUCA was greater in the GW compared to SW for the ozone processes but similar for UV/H2O2. The formation of n-C PFCA followed O3>O3/H2O2 at same dose and UV/H2O2 had much lower formation at the doses tested. Non-targeted analysis with the LC-MS-qTOF indicated the production of other PFCAs which contribute to the total mass balance, although no intermediate product was discovered indicating a rapid and direct transformation from the FTUCAs to the PFCAs and/or significant volatilization of intermediates. With the use of AOPs essential to water reuse treatment schemes, this work raises concerns over the risk of potential formation of PFCAs in the treatment and their adverse health effects in finished drinking water. PMID:26524147

  18. Decontamination of soil washing wastewater using solar driven advanced oxidation processes.

    PubMed

    Bandala, Erick R; Velasco, Yuridia; Torres, Luis G

    2008-12-30

    Decontamination of soil washing wastewater was performed using two different solar driven advanced oxidation processes (AOPs): the photo-Fenton reaction and the cobalt/peroxymonosulfate/ultraviolet (Co/PMS/UV) process. Complete sodium dodecyl sulphate (SDS), the surfactant agent used to enhance soil washing process, degradation was achieved when the Co/PMS/UV process was used. In the case of photo-Fenton reaction, almost complete SDS degradation was achieved after the use of almost four times the actual energy amount required by the Co/PMS/UV process. Initial reaction rate in the first 15min (IR15) was determined for each process in order to compare them. Highest IR15 value was determined for the Co/PMS/UV process (0.011mmol/min) followed by the photo-Fenton reaction (0.0072mmol/min) and the dark Co/PMS and Fenton processes (IR15=0.002mmol/min in both cases). Organic matter depletion in the wastewater, as the sum of surfactant and total petroleum hydrocarbons present (measured as chemical oxygen demand, COD), was also determined for both solar driven processes. It was found that, for the case of COD, the highest removal (69%) was achieved when photo-Fenton reaction was used whereas Co/PMS/UV process yielded a slightly lower removal (51%). In both cases, organic matter removal achieved was over 50%, which can be consider proper for the coupling of the tested AOPs with conventional wastewater treatment processes such as biodegradation.

  19. Transformation of polyfluorinated compounds in natural waters by advanced oxidation processes.

    PubMed

    Anumol, Tarun; Dagnino, Sonia; Vandervort, Darcy R; Snyder, Shane A

    2016-02-01

    The presence of perfluorocarboxylic acids (PFCAs) in source and finished drinking waters is a concern with studies showing bioaccumulation and adverse toxicological effects in wildlife and potentially humans. Per/Polyfluoroalkyl substances (PFAS) such as fluorotelomer alcohols have been identified as precursors for PFCAs in biological pathways. In this study, we investigated the fate of 6:2 and 8:2 homologues of the fluorotelomer unsaturated carboxylic acids (FTUCAs) during advanced oxidation process (AOPs). Results showed 6:2 FTUCA and 8:2 FTUCA transformed into 6-C PFCA (PFHxA) and 8-C PFCA (PFOA) respectively with very little other PFCA formation for all AOPs. The degradation of 6:2 FTUCA and 8:2 FTUCA was greater in the GW compared to SW for the ozone processes but similar for UV/H2O2. The formation of n-C PFCA followed O3>O3/H2O2 at same dose and UV/H2O2 had much lower formation at the doses tested. Non-targeted analysis with the LC-MS-qTOF indicated the production of other PFCAs which contribute to the total mass balance, although no intermediate product was discovered indicating a rapid and direct transformation from the FTUCAs to the PFCAs and/or significant volatilization of intermediates. With the use of AOPs essential to water reuse treatment schemes, this work raises concerns over the risk of potential formation of PFCAs in the treatment and their adverse health effects in finished drinking water.

  20. Decontamination of soil washing wastewater using solar driven advanced oxidation processes.

    PubMed

    Bandala, Erick R; Velasco, Yuridia; Torres, Luis G

    2008-12-30

    Decontamination of soil washing wastewater was performed using two different solar driven advanced oxidation processes (AOPs): the photo-Fenton reaction and the cobalt/peroxymonosulfate/ultraviolet (Co/PMS/UV) process. Complete sodium dodecyl sulphate (SDS), the surfactant agent used to enhance soil washing process, degradation was achieved when the Co/PMS/UV process was used. In the case of photo-Fenton reaction, almost complete SDS degradation was achieved after the use of almost four times the actual energy amount required by the Co/PMS/UV process. Initial reaction rate in the first 15min (IR15) was determined for each process in order to compare them. Highest IR15 value was determined for the Co/PMS/UV process (0.011mmol/min) followed by the photo-Fenton reaction (0.0072mmol/min) and the dark Co/PMS and Fenton processes (IR15=0.002mmol/min in both cases). Organic matter depletion in the wastewater, as the sum of surfactant and total petroleum hydrocarbons present (measured as chemical oxygen demand, COD), was also determined for both solar driven processes. It was found that, for the case of COD, the highest removal (69%) was achieved when photo-Fenton reaction was used whereas Co/PMS/UV process yielded a slightly lower removal (51%). In both cases, organic matter removal achieved was over 50%, which can be consider proper for the coupling of the tested AOPs with conventional wastewater treatment processes such as biodegradation. PMID:18423856