Sample records for reduction process reduccion

  1. Resist process optimization for further defect reduction

    NASA Astrophysics Data System (ADS)

    Tanaka, Keiichi; Iseki, Tomohiro; Marumoto, Hiroshi; Takayanagi, Koji; Yoshida, Yuichi; Uemura, Ryouichi; Yoshihara, Kosuke

    2012-03-01

    Defect reduction has become one of the most important technical challenges in device mass-production. Knowing that resist processing on a clean track strongly impacts defect formation in many cases, we have been trying to improve the track process to enhance customer yield. For example, residual type defect and pattern collapse are strongly related to process parameters in developer, and we have reported new develop and rinse methods in the previous papers. Also, we have reported the optimization method of filtration condition to reduce bridge type defects, which are mainly caused by foreign substances such as gels in resist. Even though we have contributed resist caused defect reduction in past studies, defect reduction requirements continue to be very important. In this paper, we will introduce further process improvements in terms of resist defect reduction, including the latest experimental data.

  2. [Treatment of acrylate wastewater by electrocatalytic reduction process].

    PubMed

    Yu, Li-Na; Song, Yu-Dong; Zhou, Yue-Xi; Zhu, Shu-Quan; Zheng, Sheng-Zhi; Ll, Si-Min

    2011-10-01

    High-concentration acrylate wastewater was treated by an electrocatalytic reduction process. The effects of the cation exchange membrane (CEM) and cathode materials on acrylate reduction were investigated. It indicated that the acrylate could be reduced to propionate acid efficiently by the electrocatalytic reduction process. The addition of CEM to separator with the cathode and anode could significantly improve current efficiency. The cathode materials had significant effect on the reduction of acrylate. The current efficiency by Pd/Nickel foam, was greater than 90%, while those by nickel foam, the carbon fibers and the stainless steel decreased successively. Toxicity of the wastewater decreased considerably and methane production rate in the biochemical methane potential (BMP) test increased greatly after the electrocatalytic reduction process.

  3. Toxicity reduction of photo processing wastewaters

    USGS Publications Warehouse

    Wang, W.

    1992-01-01

    The photo processing industry can be characterized by treatment processes and subsequent silver recovery. The effluents generated all contain various amounts of silver. The objectives of this study were to determine toxicity of photo processing effluents and to explore their toxicity mitigation. Six samples, from small shops to a major photo processing center, were studied. Two samples (I and VI) were found to be extremely toxic, causing 100 and 99% inhibition of duckweed frond reproduction, respectively, and were used for subsequent toxicity reduction experiments. Lime and sodium sulfide were effective for the toxicity reduction of Sample VI; both reduced its toxicity to negligible. Sample I was far more toxic and was first diluted to 2.2% and then treated with 0.5 g lime/100 mL, reducing toxicity from 100% to 12% inhibition.

  4. Pilot scale treatment of chromite ore processing residue using sodium sulfide in single reduction and coupled reduction/stabilization processes.

    PubMed

    Velasco, Antonio; Ramírez, Martha; Hernández, Sergio; Schmidt, Winfried; Revah, Sergio

    2012-03-15

    Single Cr(VI) reduction and coupled reduction/stabilization (R/S) processes were evaluated at pilot scale to determine their effectiveness to treat chromite ore processing residue (COPR). Sodium sulfide was used as the reducing agent and cement, gypsum and lime were tested as the stabilizing agents. The pilot experiments were performed in a helical ribbon blender mixer with batches of 250 kg of COPR and mixing time up to 30 min. Na2S/Cr(VI) mass ratios of 4.6, 5.7 and 6.8 were evaluated in the single reduction process to treat COPR with Cr(VI) concentration of ≈4.2 g/kg. The R/S process was tested with a Na2S/Cr(VI) mass ratio of 5.7 and including stabilizing agents not exceeding 5% (w/w(COPR)), to treat COPR with a Cr(VI) content of ≈5.1g/kg. The single reduction process with a ratio of 6.8, reached Cr(VI) reduction efficiencies up to 97.6% in the first days, however these values decreased to around 93% after 380 days of storage. At this point the total Cr level was around 12.5 mg/L. Cr(VI) removal efficiencies exceeding 96.5% were reached and maintained during 380 days when the coupled R/S process was evaluated. Total Cr levels lower than 5 mg/l were attained at the initials days in all R/S batch tested, however after 380 days, concentrations below the regulatory limit were only found with gypsum (2%) as single agent and with a blend of cement (4%) and lime (1%). These results indicated that the coupled R/S process is an excellent alternative to stabilize COPR. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Carbon dioxide reduction by the Bosch process

    NASA Technical Reports Server (NTRS)

    Manning, M. P.; Reid, R. C.

    1975-01-01

    Prototype units for carrying out the reduction of carbon dioxide to elementary carbon have been built and operated successfully. In some cases, however, startup difficulties have been reported. Moreover, the recycle reactor product has been reported to contain only small amounts of water and undesirably high yields of methane. This paper presents the results of the first phase of an experimental study that was carried out to define the mechanisms occurring in the reduction process. Conclusions are drawn and possible modifications to the present recycle process are suggested.

  6. Investigation of the reduction process of dopamine using paired pulse voltammetry

    PubMed Central

    Kim, Do Hyoung; Oh, Yoonbae; Shin, Hojin; Blaha, Charles D.; Bennet, Kevin E.; Lee, Kendall H.; Kim, In Young; Jang, Dong Pyo

    2014-01-01

    The oxidation of dopamine (DA) around +0.6V potential in anodic sweep and its reduction around −0.1V in cathodic sweep at a relatively fast scanning rate (300 V/s or greater) have been used for identification of DA oxidation in fast-scan cyclic voltammetry (FSCV). However, compared to the oxidation peak of DA, the reduction peak has not been fully examined in analytical studies, although it has been used as one of the representative features to identify DA. In this study, the reduction process of DA was investigated using paired pulse voltammetry (PPV), which consists of two identical triangle-shaped waveforms, separated by a short interval at the holding potential. Especially, the discrepancies between the magnitude of the oxidation and reduction peaks of DA were investigated based on three factors: (1) the instant desorption of the DA oxidation product (dopamine-o-quinone: DOQ) after production, (2) the effect of the holding potential on the reduction process, and (3) the rate-limited reduction process of DA. For the first test, the triangle waveform FSCV experiment was performed on DA with various scanrates (from 400 to 1000 V/s) and durations of switching potentials of the triangle waveform (from 0.0 to 6.0 ms) in order to vary the duration between the applied oxidation potential at +0.6V and the reduction potential at −0.2V. As a result, the ratio of reduction over oxidation peak current response decreased as the duration became longer. To evaluate the effect of holding potentials during the reduction process, FSCV experiments were conducted with holding potential from 0.0V to −0.8V. We found that more negative holding potentials lead to larger amount of reduction process. For evaluation of the rate-limited reduction process of DA, PPV with a 1Hz repetition rate and various delays (2, 8, 20, 40 and 80ms) between the paired scans were utilized to determine how much reduction process occurred during the holding potential (−0.4V). These tests showed that

  7. Reduction of metal oxides through mechanochemical processing

    DOEpatents

    Froes, Francis H.; Eranezhuth, Baburaj G.; Senkov, Oleg N.

    2000-01-01

    The low temperature reduction of a metal oxide using mechanochemical processing techniques. The reduction reactions are induced mechanically by milling the reactants. In one embodiment of the invention, titanium oxide TiO.sub.2 is milled with CaH.sub.2 to produce TiH.sub.2. Low temperature heat treating, in the range of 400.degree. C. to 700.degree. C., can be used to remove the hydrogen in the titanium hydride.

  8. Reductive stripping process for uranium recovery from organic extracts

    DOEpatents

    Hurst, F.J. Jr.

    1983-06-16

    In the reductive stripping of uranium from an organic extractant in a uranium recovery process, the use of phosphoric acid having a molarity in the range of 8 to 10 increases the efficiency of the reductive stripping and allows the strip step to operate with lower aqueous to organic recycle ratios and shorter retention time in the mixer stages. Under these operating conditions, less solvent is required in the process, and smaller, less expensive process equipment can be utilized. The high strength H/sub 3/PO/sub 4/ is available from the evaporator stage of the process.

  9. Reductive stripping process for uranium recovery from organic extracts

    DOEpatents

    Hurst, Jr., Fred J.

    1985-01-01

    In the reductive stripping of uranium from an organic extractant in a uranium recovery process, the use of phosphoric acid having a molarity in the range of 8 to 10 increases the efficiency of the reductive stripping and allows the strip step to operate with lower aqueous to organic recycle ratios and shorter retention time in the mixer stages. Under these operating conditions, less solvent is required in the process, and smaller, less expensive process equipment can be utilized. The high strength H.sub.3 PO.sub.4 is available from the evaporator stage of the process.

  10. Pre-Processed Recursive Lattice Reduction for Complexity Reduction in Spatially and Temporally Correlated MIMO Channels

    NASA Astrophysics Data System (ADS)

    An, Chan-Ho; Yang, Janghoon; Jang, Seunghun; Kim, Dong Ku

    In this letter, a pre-processed lattice reduction (PLR) scheme is developed for the lattice reduction aided (LRA) detection of multiple input multiple-output (MIMO) systems in spatially correlated channel. The PLR computes the LLL-reduced matrix of the equivalent matrix, which is the product of the present channel matrix and unimodular transformation matrix for LR of spatial correlation matrix, rather than the present channel matrix itself. In conjunction with PLR followed by recursive lattice reduction (RLR) scheme [7], pre-processed RLR (PRLR) is shown to efficiently carry out the LR of the channel matrix, especially for the burst packet message in spatially and temporally correlated channel while matching the performance of conventional LRA detection.

  11. Reductive stripping process for the recovery of uranium from wet-process phosphoric acid

    DOEpatents

    Hurst, Fred J.; Crouse, David J.

    1984-01-01

    A reductive stripping flow sheet for recovery of uranium from wet-process phosphoric acid is described. Uranium is stripped from a uranium-loaded organic phase by a redox reaction converting the uranyl to uranous ion. The uranous ion is reoxidized to the uranyl oxidation state to form an aqueous feed solution highly concentrated in uranium. Processing of this feed through a second solvent extraction cycle requires far less stripping reagent as compared to a flow sheet which does not include the reductive stripping reaction.

  12. Effect of temperature in the selective reduction process of limonite nickel ore

    NASA Astrophysics Data System (ADS)

    Mayangsari, W.; Febriana, Eni; Prasetyo, A. B.

    2018-05-01

    Temperature is the main factor for the reduction process that influence to reduction degree, phase and morphology transformation. In order to determine these effects which is caused by reduction temperature, this study was conducted. Limoniticnickel ore was prepared by drying and size reduction. A part of prepared limonitewas characterized with XRF to determine the chemical composition. The other part was mixed with reducing agent and CaSO4 to produce pellet. A series of selective reduction processes were conducted to the pellet by using graphite crucible in the muffle furnace carbolite at 800° - 1100°C for 60 minutes. Reduced ore characterized by using XRD and SEM analysis. Based on the result study, weight loss and reduction degree increase as temperature raised along with CaSO4 addition. Moreover, it caused decomposition and transformation to the metallic phase of kamacite and iron up to 7.51% and 41.44% respectively in the reduction process at 1100°C for 60 minutes. Furthermore, particle size growth as metallic phase content increased.

  13. Cleaner Production of Ti Powder by a Two-Stage Aluminothermic Reduction Process

    NASA Astrophysics Data System (ADS)

    Zhao, Kun; Wang, Yaowu; Feng, Naixiang

    2017-10-01

    A two-stage aluminothermic reduction process for preparing Ti powder under vacuum conditions using Na2TiF6 was investigated. An Al-Ti master alloy and a clean cryolite were simultaneously obtained as co-products. The first-stage reduction was an exothermic process that occurred at approximately 660°C. The Al and O contents of the Ti powder product were 0.18 wt.% and 0.35 wt.%, respectively, with an average particle size <74 μm. Ti(IV), Ti(III), and metallic Ti were present in the Ti-containing cryolite produced by the first-stage reduction, at a total content of approximately 3.13 wt.%. After second-stage reduction, the Ti elemental contents of the clean cryolite were reduced to 0.002 wt.%. The Al-Ti master alloy obtained by second-stage reduction was composed of Al and TiAl3. The mechanisms involved in these reduction processes were also examined.

  14. Processing industrial wastes with the liquid-phase reduction romelt process

    NASA Astrophysics Data System (ADS)

    Romenets, V.; Valavin, V.; Pokhvisnev, Yu.; Vandariev, S.

    1999-08-01

    The Romelt technology for liquid-phase reduction has been developed for processing metallurgical wastes containing nonferrousmetal components. Thermodynamic calculations were made to investigate the behavior of silver, copper, zinc, manganese, vanadium, chrome, and silicon when reduced from the slag melt into the metallic solution containing iron. The process can be applied to all types of iron-bearing wastes, including electric arc furnace dust. The distribution of elements between the phases can be controlled by adjusting the slag bath temperature. Experiments at a pilot Romelt plant proved the possibility of recovering the metallurgical wastes and obtaining iron.

  15. Occupational Noise Reduction in CNC Striping Process

    NASA Astrophysics Data System (ADS)

    Mahmad Khairai, Kamarulzaman; Shamime Salleh, Nurul; Razlan Yusoff, Ahmad

    2018-03-01

    Occupational noise hearing loss with high level exposure is common occupational hazards. In CNC striping process, employee that exposed to high noise level for a long time as 8-hour contributes to hearing loss, create physical and psychological stress that reduce productivity. In this paper, CNC stripping process with high level noises are measured and reduced to the permissible noise exposure. First condition is all machines shutting down and second condition when all CNC machine under operations. For both conditions, noise exposures were measured to evaluate the noise problems and sources. After improvement made, the noise exposures were measured to evaluate the effectiveness of reduction. The initial average noise level at the first condition is 95.797 dB (A). After the pneumatic system with leakage was solved, the noise reduced to 55.517 dB (A). The average noise level at the second condition is 109.340 dB (A). After six machines were gathered at one area and cover that area with plastic curtain, the noise reduced to 95.209 dB (A). In conclusion, the noise level exposure in CNC striping machine is high and exceed the permissible noise exposure can be reduced to acceptable levels. The reduction of noise level in CNC striping processes enhanced productivity in the industry.

  16. Molecular Modeling of Environmentally Important Processes: Reduction Potentials

    ERIC Educational Resources Information Center

    Lewis, Anne; Bumpus, John A.; Truhlar, Donald G.; Cramer, Christopher J.

    2004-01-01

    The increasing use of computational quantum chemistry in the modeling of environmentally important processes is described. The employment of computational quantum mechanics for the prediction of oxidation-reduction potential for solutes in an aqueous medium is discussed.

  17. Characteristics of sludge reduction in an integrated pretreatment and aerobic digestion process.

    PubMed

    Hwang, S; Jang, H; Lee, M; Song, J; Kim, S

    2006-01-01

    In this study, integrated pretreatments and aerobic digestion processes were investigated in order to provide a feasible alternative that can achieve effective sludge reduction. An ozone treatment in the presence of ionic manganese, a catalyst, increased the sludge reduction ratio three times higher than that of a single ozonation, presumably due to an increase in OH radical production. The ozone treatment yielded the effective sludge reduction ratio with an increasing ozone dosage, and an effective dosage of the catalyst was found to be 4 mg-Mn/g-TS. When a mechanical pretreatment and an ozone/catalyst were applied in a series, the integrated process, even at a half mechanical intensity and a half level of ozone dosage, showed higher and faster sludge reduction than each single process did. In addition, the integrated pretreatment process showed the highest dewaterability of the treated sludges. A ratio of sludge cake generation, which was newly introduced to quantify overall performance of sludge treatment processes, showed that the integrated pretreatment followed by the aerobic digestion yielded approximately a half of the sludge cake volume compared to the single aerobic digestion. Therefore, the integrated pretreatment can be a feasible method for the effective reduction of total suspended solid and the final volume.

  18. The electrochemical reduction processes of solid compounds in high temperature molten salts.

    PubMed

    Xiao, Wei; Wang, Dihua

    2014-05-21

    Solid electrode processes fall in the central focus of electrochemistry due to their broad-based applications in electrochemical energy storage/conversion devices, sensors and electrochemical preparation. The electrolytic production of metals, alloys, semiconductors and oxides via the electrochemical reduction of solid compounds (especially solid oxides) in high temperature molten salts has been well demonstrated to be an effective and environmentally friendly process for refractory metal extraction, functional materials preparation as well as spent fuel reprocessing. The (electro)chemical reduction of solid compounds under cathodic polarizations generally accompanies a variety of changes at the cathode/melt electrochemical interface which result in diverse electrolytic products with different compositions, morphologies and microstructures. This report summarizes various (electro)chemical reactions taking place at the compound cathode/melt interface during the electrochemical reduction of solid compounds in molten salts, which mainly include: (1) the direct electro-deoxidation of solid oxides; (2) the deposition of the active metal together with the electrochemical reduction of solid oxides; (3) the electro-inclusion of cations from molten salts; (4) the dissolution-electrodeposition process, and (5) the electron hopping process and carbon deposition with the utilization of carbon-based anodes. The implications of the forenamed cathodic reactions on the energy efficiency, chemical compositions and microstructures of the electrolytic products are also discussed. We hope that a comprehensive understanding of the cathodic processes during the electrochemical reduction of solid compounds in molten salts could form a basis for developing a clean, energy efficient and affordable production process for advanced/engineering materials.

  19. Numerical Study of the Reduction Process in an Oxygen Blast Furnace

    NASA Astrophysics Data System (ADS)

    Zhang, Zongliang; Meng, Jiale; Guo, Lei; Guo, Zhancheng

    2016-02-01

    Based on computational fluid dynamics, chemical reaction kinetics, principles of transfer in metallurgy, and other principles, a multi-fluid model for a traditional blast furnace was established. The furnace conditions were simulated with this multi-fluid mathematical model, and the model was verified with the comparison of calculation and measurement. Then a multi-fluid model for an oxygen blast furnace in the gasifier-full oxygen blast furnace process was established based on this traditional blast furnace model. With the established multi-fluid model for an oxygen blast furnace, the basic characteristics of iron ore reduction process in the oxygen blast furnace were summarized, including the changing process of the iron ore reduction degree and the compositions of the burden, etc. The study found that compared to the traditional blast furnace, the magnetite reserve zone in the furnace shaft under oxygen blast furnace condition was significantly reduced, which is conducive to the efficient operation of blast furnace. In order to optimize the oxygen blast furnace design and operating parameters, the iron ore reduction process in the oxygen blast furnace was researched under different shaft tuyere positions, different recycling gas temperatures, and different allocation ratios of recycling gas between the hearth tuyere and the shaft tuyere. The results indicate that these three factors all have a substantial impact on the ore reduction process in the oxygen blast furnace. Moderate shaft tuyere position, high recycling gas temperature, and high recycling gas allocation ratio between hearth and shaft could significantly promote the reduction of iron ore, reduce the scope of the magnetite reserve zone, and improve the performance of oxygen blast furnace. Based on the above findings, the recommendations for improvement of the oxygen blast furnace design and operation were proposed.

  20. Computer program developed for flowsheet calculations and process data reduction

    NASA Technical Reports Server (NTRS)

    Alfredson, P. G.; Anastasia, L. J.; Knudsen, I. E.; Koppel, L. B.; Vogel, G. J.

    1969-01-01

    Computer program PACER-65, is used for flowsheet calculations and easily adapted to process data reduction. Each unit, vessel, meter, and processing operation in the overall flowsheet is represented by a separate subroutine, which the program calls in the order required to complete an overall flowsheet calculation.

  1. Oxidation-reduction processes in ground water at Naval Weapons Industrial Reserve Plant, Dallas, Texas

    USGS Publications Warehouse

    Jones, S.A.; Braun, Christopher L.; Lee, Roger W.

    2003-01-01

    Concentrations of trichloroethene in ground water at the Naval Weapons Industrial Reserve Plant in Dallas, Texas, indicate three source areas of chlorinated solvents?building 1, building 6, and an off-site source west of the facility. The presence of daughter products of reductive dechlorination of trichloroethene, which were not used at the facility, south and southwest of the source areas are evidence that reductive dechlorination is occurring. In places south of the source areas, dissolved oxygen concentrations indicated that reduction of oxygen could be the dominant process, particularly south of building 6; but elevated dissolved oxygen concentrations south of building 6 might be caused by a leaking water or sewer pipe. The nitrite data indicate that denitrification is occurring in places; however, dissolved hydrogen concentrations indicate that iron reduction is the dominant process south of building 6. The distributions of ferrous iron indicate that iron reduction is occurring in places south-southwest of buildings 6 and 1; dissolved hydrogen concentrations generally support the interpretation that iron reduction is the dominant process in those places. The generally low concentrations of sulfide indicate that sulfate reduction is not a key process in most sampled areas, an interpretation that is supported by dissolved hydrogen concentrations. Ferrous iron and dissolved hydrogen concentrations indicate that ferric iron reduction is the primary oxidation-reduction process. Application of mean first-order decay rates in iron-reducing conditions for trichloroethene, dichloroethene, and vinyl chloride yielded half-lives for those solvents of 231, 347, and 2.67 days, respectively. Decay rates, and thus half-lives, at the facility are expected to be similar to those computed. A weighted scoring method to indicate sites where reductive dechlorination might be likely to occur indicated strong evidence for anaerobic biodegradation of chlorinated solvents at six sites

  2. Survival in a Down Economy: A Budget Reduction Process for Superintendents

    ERIC Educational Resources Information Center

    Davis, E. E.; Coffland, Jack A.

    2010-01-01

    Dramatic reductions in the dollars available for public education require a new and systemic approach to balancing school district budgets. This manual provides numerous examples of successful budget reduction strategies based on a six-step process that has demonstrated its effectiveness in small, medium, and large school districts. Supported by…

  3. Review of Manganese Processing for Production of TRIP/TWIP Steels, Part 2: Reduction Studies

    NASA Astrophysics Data System (ADS)

    Elliott, R.; Coley, K.; Mostaghel, S.; Barati, M.

    2018-02-01

    Production of ultrahigh-manganese steels is expected to result in significant increase in demand for low-carbon (LC) ferromanganese (FeMn) and silicomanganese (SiMn). Current manganese processing techniques are energy intensive and typically yield a high-carbon product. The present work therefore reviews available literature regarding carbothermic reduction of Mn oxides and ores, with the objective of identifying opportunities for future process development to mitigate the cost of LC FeMn and SiMn. In general, there is consensus that carbothermic reduction of Mn oxides and ores is limited by gasification of carbon. Conditions which enhance or bypass this step (e.g., by application of CH4) show higher rates of reduction at lower temperatures. This phenomenon has potential application in solid-state reduction of Mn ore. Other avenues for process development include optimization of the prereduction step in conventional FeMn production and metallothermic reduction as a secondary reduction step.

  4. Direct reduction processes for titanium oxide in molten salt

    NASA Astrophysics Data System (ADS)

    Suzuki, Ryosuke O.

    2007-02-01

    Molten salt electrolysis using CaCl2 is employed to produce pure titanium and its alloys directly from TiO2 and a mixture of elemental oxides, respectively, as an alternate to the Kroll process. This is because CaO, which is a reduction by-product, is highly soluble in CaCl2. Good-quality titanium containing only a small amount of residual oxygen has been successfully produced and scaled to industrial levels. Thermochemical and electrochemical bases are reviewed to optimize the process conditions. Several processes using molten salt are being examined for future progress in titanium processing.

  5. 10 CFR 9.43 - Processing requests for a waiver or reduction of fees.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Processing requests for a waiver or reduction of fees. 9.43 Section 9.43 Energy NUCLEAR REGULATORY COMMISSION PUBLIC RECORDS Freedom of Information Act Regulations § 9.43 Processing requests for a waiver or reduction of fees. (a) Within 20 working days after...

  6. 10 CFR 9.43 - Processing requests for a waiver or reduction of fees.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Processing requests for a waiver or reduction of fees. 9.43 Section 9.43 Energy NUCLEAR REGULATORY COMMISSION PUBLIC RECORDS Freedom of Information Act Regulations § 9.43 Processing requests for a waiver or reduction of fees. (a) Within 20 working days after...

  7. 10 CFR 9.43 - Processing requests for a waiver or reduction of fees.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Processing requests for a waiver or reduction of fees. 9.43 Section 9.43 Energy NUCLEAR REGULATORY COMMISSION PUBLIC RECORDS Freedom of Information Act Regulations § 9.43 Processing requests for a waiver or reduction of fees. (a) Within 20 working days after...

  8. 10 CFR 9.43 - Processing requests for a waiver or reduction of fees.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Processing requests for a waiver or reduction of fees. 9.43 Section 9.43 Energy NUCLEAR REGULATORY COMMISSION PUBLIC RECORDS Freedom of Information Act Regulations § 9.43 Processing requests for a waiver or reduction of fees. (a) Within 20 working days after...

  9. 10 CFR 9.43 - Processing requests for a waiver or reduction of fees.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Processing requests for a waiver or reduction of fees. 9.43 Section 9.43 Energy NUCLEAR REGULATORY COMMISSION PUBLIC RECORDS Freedom of Information Act Regulations § 9.43 Processing requests for a waiver or reduction of fees. (a) Within 20 working days after...

  10. Dimension Reduction of Multivariable Optical Emission Spectrometer Datasets for Industrial Plasma Processes

    PubMed Central

    Yang, Jie; McArdle, Conor; Daniels, Stephen

    2014-01-01

    A new data dimension-reduction method, called Internal Information Redundancy Reduction (IIRR), is proposed for application to Optical Emission Spectroscopy (OES) datasets obtained from industrial plasma processes. For example in a semiconductor manufacturing environment, real-time spectral emission data is potentially very useful for inferring information about critical process parameters such as wafer etch rates, however, the relationship between the spectral sensor data gathered over the duration of an etching process step and the target process output parameters is complex. OES sensor data has high dimensionality (fine wavelength resolution is required in spectral emission measurements in order to capture data on all chemical species involved in plasma reactions) and full spectrum samples are taken at frequent time points, so that dynamic process changes can be captured. To maximise the utility of the gathered dataset, it is essential that information redundancy is minimised, but with the important requirement that the resulting reduced dataset remains in a form that is amenable to direct interpretation of the physical process. To meet this requirement and to achieve a high reduction in dimension with little information loss, the IIRR method proposed in this paper operates directly in the original variable space, identifying peak wavelength emissions and the correlative relationships between them. A new statistic, Mean Determination Ratio (MDR), is proposed to quantify the information loss after dimension reduction and the effectiveness of IIRR is demonstrated using an actual semiconductor manufacturing dataset. As an example of the application of IIRR in process monitoring/control, we also show how etch rates can be accurately predicted from IIRR dimension-reduced spectral data. PMID:24451453

  11. Gene regulation and noise reduction by coupling of stochastic processes

    NASA Astrophysics Data System (ADS)

    Ramos, Alexandre F.; Hornos, José Eduardo M.; Reinitz, John

    2015-02-01

    Here we characterize the low-noise regime of a stochastic model for a negative self-regulating binary gene. The model has two stochastic variables, the protein number and the state of the gene. Each state of the gene behaves as a protein source governed by a Poisson process. The coupling between the two gene states depends on protein number. This fact has a very important implication: There exist protein production regimes characterized by sub-Poissonian noise because of negative covariance between the two stochastic variables of the model. Hence the protein numbers obey a probability distribution that has a peak that is sharper than those of the two coupled Poisson processes that are combined to produce it. Biochemically, the noise reduction in protein number occurs when the switching of the genetic state is more rapid than protein synthesis or degradation. We consider the chemical reaction rates necessary for Poisson and sub-Poisson processes in prokaryotes and eucaryotes. Our results suggest that the coupling of multiple stochastic processes in a negative covariance regime might be a widespread mechanism for noise reduction.

  12. Gene regulation and noise reduction by coupling of stochastic processes

    PubMed Central

    Hornos, José Eduardo M.; Reinitz, John

    2015-01-01

    Here we characterize the low noise regime of a stochastic model for a negative self-regulating binary gene. The model has two stochastic variables, the protein number and the state of the gene. Each state of the gene behaves as a protein source governed by a Poisson process. The coupling between the the two gene states depends on protein number. This fact has a very important implication: there exist protein production regimes characterized by sub-Poissonian noise because of negative covariance between the two stochastic variables of the model. Hence the protein numbers obey a probability distribution that has a peak that is sharper than those of the two coupled Poisson processes that are combined to produce it. Biochemically, the noise reduction in protein number occurs when the switching of genetic state is more rapid than protein synthesis or degradation. We consider the chemical reaction rates necessary for Poisson and sub-Poisson processes in prokaryotes and eucaryotes. Our results suggest that the coupling of multiple stochastic processes in a negative covariance regime might be a widespread mechanism for noise reduction. PMID:25768447

  13. Gene regulation and noise reduction by coupling of stochastic processes.

    PubMed

    Ramos, Alexandre F; Hornos, José Eduardo M; Reinitz, John

    2015-02-01

    Here we characterize the low-noise regime of a stochastic model for a negative self-regulating binary gene. The model has two stochastic variables, the protein number and the state of the gene. Each state of the gene behaves as a protein source governed by a Poisson process. The coupling between the two gene states depends on protein number. This fact has a very important implication: There exist protein production regimes characterized by sub-Poissonian noise because of negative covariance between the two stochastic variables of the model. Hence the protein numbers obey a probability distribution that has a peak that is sharper than those of the two coupled Poisson processes that are combined to produce it. Biochemically, the noise reduction in protein number occurs when the switching of the genetic state is more rapid than protein synthesis or degradation. We consider the chemical reaction rates necessary for Poisson and sub-Poisson processes in prokaryotes and eucaryotes. Our results suggest that the coupling of multiple stochastic processes in a negative covariance regime might be a widespread mechanism for noise reduction.

  14. Thermodynamic Investigation of the Reduction-Distillation Process for Rare Earth Metals Production

    NASA Astrophysics Data System (ADS)

    Judge, W. D.; Azimi, G.

    2017-10-01

    Owing to their high vapor pressure, the four rare earth metals samarium, europium, thulium, and ytterbium are produced by reduction-distillation whereby their oxides are reduced with metallic lanthanum in vacuo, and the produced metal is subsequently vaporized off. Here, we performed a thorough thermodynamic investigation to establish a fundamental understanding of the reduction-distillation process. Thermodynamic functions including vapor pressures, Gibbs free energies, and enthalpies of reaction were calculated and compared with available experimental data. Furthermore, the kinetics of the process was explored and theoretical evaporation rates were calculated from thermodynamic data. The thermodynamic model developed in this work can help optimize processing conditions to maximize the yield and improve the overall process.

  15. Simulation of multivariate stationary stochastic processes using dimension-reduction representation methods

    NASA Astrophysics Data System (ADS)

    Liu, Zhangjun; Liu, Zenghui; Peng, Yongbo

    2018-03-01

    In view of the Fourier-Stieltjes integral formula of multivariate stationary stochastic processes, a unified formulation accommodating spectral representation method (SRM) and proper orthogonal decomposition (POD) is deduced. By introducing random functions as constraints correlating the orthogonal random variables involved in the unified formulation, the dimension-reduction spectral representation method (DR-SRM) and the dimension-reduction proper orthogonal decomposition (DR-POD) are addressed. The proposed schemes are capable of representing the multivariate stationary stochastic process with a few elementary random variables, bypassing the challenges of high-dimensional random variables inherent in the conventional Monte Carlo methods. In order to accelerate the numerical simulation, the technique of Fast Fourier Transform (FFT) is integrated with the proposed schemes. For illustrative purposes, the simulation of horizontal wind velocity field along the deck of a large-span bridge is proceeded using the proposed methods containing 2 and 3 elementary random variables. Numerical simulation reveals the usefulness of the dimension-reduction representation methods.

  16. Ochratoxin A reduction in meat sausages using processing methods practiced in households.

    PubMed

    Pleadin, Jelka; Perši, Nina; Kovačević, Dragan; Vulić, Ana; Frece, Jadranka; Markov, Ksenija

    2014-01-01

    The aim of this study was to investigate the possibilities of ochratoxin A (OTA) reduction in home-made meat products. Meat sausages (n = 50) produced from raw materials coming from pigs exposed to OTA-contaminated feed, were subject to common heat processes practiced in households (cooking, frying and baking). Concentrations of OTA in pre- and post-processed products were quantified using a validated immunoassay method, enzyme-linked immunosorbent assay, and confirmed using a high-performance liquid chromatography with fluorescence detection. In line with the differences in recipes used and the degree of OTA accumulation in raw materials, OTA concentrations established in Mediterranean and roast sausages were lower than those found in liver and blood sausages. Baking of contaminated sausages at the temperatures of 190-220°C (for 60 min) resulted in significant reduction of OTA levels (75.8%), while 30-min cooking (at 100°C) and frying (at 170°C) proved to be significantly less effective (e.g. yielding OTA reductions of 7.4% and 12.6%, respectively). The results pointed out that despite high OTA stability, heat processes are capable of reducing its concentration in home-made meat products, depending on the processing modality used.

  17. The effect of material productivity on scrap reduction on aluminum reduction pot process

    NASA Astrophysics Data System (ADS)

    Huda, L. N.

    2018-02-01

    Scrap in the production process is defined as part of production that can not be accepted as the final product due to production failure. The amount of scarp occurring in the reduction pot production process of one of the aluminum smelting furnaces exceeds the acceptance standard of 5 to 10%. This affects the amount of production produced. The purpose of this study is to reduce the amount of scrap produced to increase the productivity of the materials used. The solution is carried-out by making improvements using Lean Six Sigma method. In the initial calculation, material productivity ranged from 0.88. Based on the study, the factors that cause the high amount of scrap produced is the use of Na2O which is inserted into the alumina is different in size and the influence of noise that occurs in pots that are difficult to control. The analysis base on Lean Six Sigma obtained process cycle efficiency (PCE) equal to 86,92% for actual condition. Process improvement is carried-out through define, measure, analyze, improve and control procedure on Na2O feeding process and PCE value decrease 6,05%. This indicates that increased process capability will reduce scrap. A decrease in scrap amount of about 6% will be able to increase material productivity by 0.05%. This indicates that continuous process control is needed to decrease the number of scraps and increase productivity.

  18. Research and Industrial Application of a Process for Direct Reduction of Molten High-Lead Smelting Slag

    NASA Astrophysics Data System (ADS)

    Li, Weifeng; Zhan, Jing; Fan, Yanqing; Wei, Chang; Zhang, Chuanfu; Hwang, Jiann-Yang

    2017-04-01

    A pyrometallurgical process for the direct reduction of molten high-lead smelting slag obtained by the Shuikoushan (SKS) method was reported in this article using solid anthracite as the fuel and reductant. The chemical composition, the lead phase composition, and the physical properties of the molten high-lead slag were examined. The effects of the process parameters on the recovery rate of valued metals were investigated in the laboratory. According to the experimental results, a new efficient bottom blow reduction furnace was employed in the pilot-scale test for high-lead slag reduction. The results showed the average recovery rate of lead was more than 96.0% with lower Pb and high Zn content of the reducing slag under the condition of reduction temperature 1100-1200°C, coal ratio 5.5-7.5%, reduction time 90-150 min, CaO/SiO2 ratio 0.35-0.45, and FeO/SiO2 ratio 1.4-1.55. Moreover, nearly 250 kg of standard coal per ton of crude Pb output was reduced compared with the blast furnace reduction process.

  19. Ceruloplasmin copper induces oxidant damage by a redox process utilizing cell-derived superoxide as reductant

    NASA Technical Reports Server (NTRS)

    Mukhopadhyay, C. K.; Fox, P. L.

    1998-01-01

    Oxidative damage by transition metals bound to proteins may be an important pathogenic mechanism. Ceruloplasmin (Cp) is a Cu-containing plasma protein thought to be involved in oxidative modification of lipoproteins. We have previously shown that Cp increased cell-mediated low-density lipoprotein (LDL) oxidation by a process requiring cell-derived superoxide, but the underlying chemical mechanism(s) is (are) unknown. We now show that superoxide reduction of Cp Cu is a critical reaction in cellular LDL oxidation. By bathocuproine disulfonate (BCS) binding and by superoxide utilization, we showed that exogenous superoxide reduces a single Cp Cu atom, the same Cu required for LDL oxidation. The Cu atom remained bound to Cp during the redox cycle. Three avenues of evidence showed that vascular cells reduce Cp Cu by a superoxide-dependent process. The 2-fold higher rate of Cp Cu reduction by smooth muscle cells (SMC) compared to endothelial cells (EC) was consistent with their relative rates of superoxide release. Furthermore, Cp Cu reduction by cells was blocked by Cu,Zn superoxide dismutase (SOD1). Finally, the level of superoxide produced by EC and SMC was sufficient to cause the amount of Cu reduction observed. An important role of Cp Cu reduction in LDL oxidation was suggested by results showing that SOD1 inhibited Cp Cu reduction and LDL oxidation by SMC with equal potency, while tumor necrosis factor-alpha stimulated both processes. In summary, these results show that superoxide is a critical cellular reductant of divalent transition metals involved in oxidation, and that protein-bound Cu is a substrate for this reaction. The role of these mechanisms in oxidative processes in vivo has yet to be defined.

  20. Use of Alum for Odor Reduction in Sludge and Biosolids from Different Wastewater Treatment Processes.

    PubMed

    Gruchlik, Yolanta; Fouché, Lise; Joll, Cynthia A; Heitz, Anna

    2017-12-01

      Applicability of alum addition to wastewater sludge and biosolids produced from different treatment processes was evaluated as a means of odor reduction. Four water resource recovery facilities (WRRFs) were chosen for this study: two used mesophilic anaerobic digestion and two used oxidation ditch processes. The experiments were conducted on a laboratory scale and in all cases the alum was added prior to dewatering. This is the first report of the application of alum for odor reduction in oxidation ditch processes. Alum addition was effective in reducing odors in anaerobically digested biosolids. Addition of 4% alum to anaerobically digested liquid biosolids prior to dewatering resulted in a 60% reduction in the peak odor concentration in the laboratory dewatered cake, relative to the control sample. Alum addition did not reduce odors in dewatered sludge from oxidation ditch processes.

  1. Reduction of non-Betalactam Antibiotics COD by Combined Coagulation and Advanced Oxidation Processes.

    PubMed

    Yazdanbakhsh, Ahmad Reza; Mohammadi, Amir Sheikh; Alinejad, Abdol Azim; Hassani, Ghasem; Golmohammadi, Sohrab; Mohseni, Seyed Mohsen; Sardar, Mahdieh; Sarsangi, Vali

    2016-11-01

      The present study evaluates the reduction of antibiotic COD from wastewater by combined coagulation and advanced oxidation processes (AOPS). The reduction of Azithromycin COD by combined coagulation and Fenton-like processes reached a maximum 96.9% at a reaction time of 30 min, dosage of ferric chloride 120 mg/L, dosages of Fe0 and H2O2of 0.36mM/L and 0.38 mM/L, respectively. Also, 97.9% of Clarithromycin COD reduction, was achieved at a reaction time of 30 min, dosage of ferric chloride 120 mg/L, dosages of Fe0 and H2O2 of 0.3 mM/L and 0.3mM/L, respectively. The results of kinetic studies were best fitted to the pseudo first order equation. The results showed a higher rate constant value for combined coagulation and Fenton-like processes [(kap = 0.022 min-1 and half-life time of 31.5 min for Azithromycin) and (kap = 0.023 min-1 and half-life time of 30.1 min for Clarithromycin)].

  2. Synthesis of Hierarchical Nanoporous Microstructures via the Kirkendall Effect in Chemical Reduction Process

    NASA Astrophysics Data System (ADS)

    Gao, Ling; Pang, Chao; He, Dafang; Shen, Liming; Gupta, Arunava; Bao, Ningzhong

    2015-11-01

    A series of novel hierarchical nanoporous microstructures have been synthesized through one-step chemical reduction of micron size Cu2O and Co3O4 particles. By controlling the reduction time, non-porous Cu2O microcubes sequentially transform to nanoporous Cu/Cu2O/Cu dented cubic composites and hollow eightling-like Cu microparticles. The mechanism involved in the complex structural evolution is explained based on oxygen diffusion and Kirkendall effect. The nanoporous Cu/Cu2O/Cu dented cubic composites exhibit superior electrochemical performance as compared to solid Cu2O microcubes. The reduction of nonporous Co3O4 also exhibits a uniform sequential reduction process from nonporous Co3O4 to porous Co3O4/CoO composites, porous CoO, porous CoO/Co composites, and porous foam-like Co particles. Nanoscale channels originate from the particle surface and eventually develop inside the entire product, resulting in porous foam-like Co microparticles. The Kirkendall effect is believed to facilitate the formation of porous structures in both processes.

  3. Effects of imposed salinity gradients on dissimilatory arsenate reduction, sulfate reduction, and other microbial processes in sediments from two California soda lakes

    USGS Publications Warehouse

    Kulp, T.R.; Han, S.; Saltikov, C.W.; Lanoil, B.D.; Zargar, K.; Oremland, R.S.

    2007-01-01

    Salinity effects on microbial community structure and on potential rates of arsenate reduction, arsenite oxidation, sulfate reduction, denitrification, and methanogenesis were examined in sediment slurries from two California soda lakes. We conducted experiments with Mono Lake and Searles Lake sediments over a wide range of salt concentrations (25 to 346 g liter-1). With the exception of sulfate reduction, rates of all processes demonstrated an inverse relationship to total salinity. However, each of these processes persisted at low but detectable rates at salt saturation. Denaturing gradient gel electrophoresis analysis of partial 16S rRNA genes amplified from As(V) reduction slurries revealed that distinct microbial populations grew at low (25 to 50 g liter-1), intermediate (100 to 200 g liter-1), and high (>300 g liter-1) salinity. At intermediate and high salinities, a close relative of a cultivated As-respiring halophile was present. These results suggest that organisms adapted to more dilute conditions can remain viable at high salinity and rapidly repopulate the lake during periods of rising lake level. In contrast to As reduction, sulfate reduction in Mono Lake slurries was undetectable at salt saturation. Furthermore, sulfate reduction was excluded from Searles Lake sediments at any salinity despite the presence of abundant sulfate. Sulfate reduction occurred in Searles Lake sediment slurries only following inoculation with Mono Lake sediment, indicating the absence of sulfate-reducing flora. Experiments with borate-amended Mono Lake slurries suggest that the notably high (0.46 molal) concentration of borate in the Searles Lake brine was responsible for the exclusion of sulfate reducers from that ecosystem. Copyright ?? 2007, American Society for Microbiology. All Rights Reserved.

  4. Recovery of Work-Related Stress: Complaint Reduction and Work-Resumption are Relatively Independent Processes.

    PubMed

    de Vente, Wieke; Kamphuis, Jan Henk; Blonk, Roland W B; Emmelkamp, Paul M G

    2015-09-01

    The process of recovery from work-related stress, consisting of complaint reduction and work-resumption, is not yet fully understood. The aim of this study was to investigate predictors of complaint reduction and work-resumption, as well as testing complaint reduction as a mediator in the association between predictors and work-resumption. Seventy-one patients on sickness-leave because of work-related stress complaints were followed over a period of 13 months. Predictors comprised personal (demographics, coping, cognitions), work-related (job-characteristics, social support), and illness-related (complaint duration, absence duration) variables. Dependent variables were distress complaints, burnout complaints, and work-resumption. Complaints reduced considerably over time to borderline clinical levels and work-resumption increased to 68% at 13 months. Predictors of stronger reduction of distress complaints were male gender, less working hours, less decision authority, more co-worker support, and shorter absence duration. Predictors of stronger reduction of burnout complaints were male gender, lower age, high education, less avoidant coping, less decision authority, more job security, and more co-worker support. Predictors of work-resumption were lower age and stronger reduction of burnout complaints. No indication for a mediating role of burnout complaints between the predictor age and work-resumption was found. Complaint reduction and work-resumption are relatively independent processes. Symptom reduction is influenced by individual and work-related characteristics, which holds promise for a multidisciplinary treatment approach for work-related stress.

  5. INCORPORATING ENVIRONMENTAL AND ECONOMIC CONSIDERATIONS INTO PROCESS DESIGN: THE WASTE REDUCTION (WAR) ALGORITHM

    EPA Science Inventory

    A general theory known as the WAste Reduction (WASR) algorithm has been developed to describe the flow and the generation of potential environmental impact through a chemical process. This theory integrates environmental impact assessment into chemical process design Potential en...

  6. Reduction of verotoxigenic Escherichia coli by process and recipe optimisation in dry-fermented sausages.

    PubMed

    Heir, E; Holck, A L; Omer, M K; Alvseike, O; Høy, M; Måge, I; Axelsson, L

    2010-07-15

    Outbreaks of verotoxigenic Escherichia coli (VTEC) linked to dry-fermented sausages (DFSs) have emphasized the need for DFS manufacturers to introduce measures to obtain enhanced safety and still maintain the sensory qualities of their products. To our knowledge no data have yet been reported on non-O157:H7 VTEC survival in DFS. Here, the importance of recipe and process variables on VTEC (O157:H7 and O103:H25) reductions in two types of DFS, morr and salami, was determined through three statistically designed experiments. Linear regression and ANOVA analyses showed that no single variable had a dominant effect on VTEC reductions. High levels of NaCl, NaNO(2), glucose (low pH) and fermentation temperature gave enhanced VTEC reduction, while high fat and large casing diameter (a(w)) gave the opposite effect. Interaction effects were small. The process and recipe variables showed similar effects in morr and salami. In general, recipes combining high batter levels of salt (NaCl and NaNO(2)) and glucose along with high fermentation temperature that gave DFS with low final pH and a(w), provided approximately 3 log(10) reductions compared to approximately 1.5 log(10) reductions obtained for standard recipe DFS. Storage at 4 degrees C for 2 months provided log(10) 0.33-0.95 additional VTEC reductions and were only marginally affected by recipe type. Sensory tests revealed only small differences between the various recipes of morr and salami. By optimisation of recipe and process parameters, it is possible to obtain increased microbial safety of DFS while maintaining the sensory qualities of the sausages. 2010 Elsevier B.V. All rights reserved.

  7. Degradation and ecotoxicity of dye Reactive Black 5 after reductive-oxidative process : Environmental Science and Pollution Research.

    PubMed

    Cuervo Lumbaque, Elisabeth; Gomes, Monike Felipe; Da Silva Carvalho, Vanessa; de Freitas, Adriane Martins; Tiburtius, Elaine Regina Lopes

    2017-03-01

    This research paper describes the study of a reduction-oxidation system using commercial steel wool (Fe 0 ) and H 2 O 2 for degradation of the dye Reactive Black 5 and aromatic compounds in water. The reductive process alone allowed the almost complete removal of color (97 ± 1 %) after 60 min of reaction. The decrease in spectral area (λ = 599 nm) associated with the chromophore group indicates breakage of the azo bonds. Moreover, the significant change in UV spectra can be associated with the formation of aromatic amines. Regarding the transformation products, a spectrophotometric method based on the diazotization reaction was employed to identify aromatic amines after reductive process, using sulfanilic acid as a model of aromatic amines. In addition, association with Fenton reagents improved the efficiency in the system with 93 ± 1 % degradation of intermediates formed during the reductive process. Ecotoxicological analysis revealed that the dye solution, after the reductive and oxidative processes, was not toxic to Lactuca sativa seeds. For Daphnia magna, the EC 50 (%) values observed revealed that dye solution has an EC 50 (%) = 74.1 and after reductive process, the toxicity increased (EC 50 (%) = 63.5), which might be related to the formation of aromatic amines. However, after the Fenton process, the EC 50 (%) was >100. These results demonstrated that the Fenton reaction using steel wool as an iron source was very efficient to decrease color, aromatic transformation products, and the ecotoxicity of Reactive Black 5 in solution.

  8. The xylooligosaccharide addition and sodium reduction in requeijão cremoso processed cheese.

    PubMed

    Ferrão, Luana L; Ferreira, Marcus Vinícius S; Cavalcanti, Rodrigo N; Carvalho, Ana Flávia A; Pimentel, Tatiana C; Silva, Hugo L A; Silva, Ramon; Esmerino, Erick A; Neto, Roberto P C; Tavares, Maria Inês B; Freitas, Mônica Q; Menezes, Jaqueline C V; Cabral, Lúcio M; Moraes, Jeremias; Silva, Márcia C; Mathias, Simone P; Raices, Renata S L; Pastore, Gláucia M; Cruz, Adriano G

    2018-05-01

    The addition of xylooligosaccharide (XOS), sodium reduction and flavor enhancers (arginine and yeast extract) on the manufacture of requeijão cremoso processed cheese was investigated. The addition of XOS resulted in a denser and compact structure, with increased apparent viscosity, elasticity (G') and firmness (G*). The addition of XOS and yeast extract improved the rheological and physicochemical properties (decrease in viscosity and particle size and increase in melting rate) and sensory characteristics (improvement in salty and acid taste, greater homogeneity, and lower bitter taste). In addition, a positive effect of arginine was observed in the sensory characteristics of the requeijão cremoso processed cheese, but without improvements in the physicochemical and rheological characteristics. Overall, the XOS addition and sodium reduction proportionated the development of a healthier processed cheese formulation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Adiabatic reduction of a model of stochastic gene expression with jump Markov process.

    PubMed

    Yvinec, Romain; Zhuge, Changjing; Lei, Jinzhi; Mackey, Michael C

    2014-04-01

    This paper considers adiabatic reduction in a model of stochastic gene expression with bursting transcription considered as a jump Markov process. In this model, the process of gene expression with auto-regulation is described by fast/slow dynamics. The production of mRNA is assumed to follow a compound Poisson process occurring at a rate depending on protein levels (the phenomena called bursting in molecular biology) and the production of protein is a linear function of mRNA numbers. When the dynamics of mRNA is assumed to be a fast process (due to faster mRNA degradation than that of protein) we prove that, with appropriate scalings in the burst rate, jump size or translational rate, the bursting phenomena can be transmitted to the slow variable. We show that, depending on the scaling, the reduced equation is either a stochastic differential equation with a jump Poisson process or a deterministic ordinary differential equation. These results are significant because adiabatic reduction techniques seem to have not been rigorously justified for a stochastic differential system containing a jump Markov process. We expect that the results can be generalized to adiabatic methods in more general stochastic hybrid systems.

  10. Selective catalytic reduction system and process using a pre-sulfated zirconia binder

    DOEpatents

    Sobolevskiy, Anatoly; Rossin, Joseph A.

    2010-06-29

    A selective catalytic reduction (SCR) process with a palladium catalyst for reducing NOx in a gas, using hydrogen as a reducing agent is provided. The process comprises contacting the gas stream with a catalyst system, the catalyst system comprising (ZrO.sub.2)SO.sub.4, palladium, and a pre-sulfated zirconia binder. The inclusion of a pre-sulfated zirconia binder substantially increases the durability of a Pd-based SCR catalyst system. A system for implementing the disclosed process is further provided.

  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. Integral blow moulding for cycle time reduction of CFR-TP aluminium contour joint processing

    NASA Astrophysics Data System (ADS)

    Barfuss, Daniel; Würfel, Veit; Grützner, Raik; Gude, Maik; Müller, Roland

    2018-05-01

    Integral blow moulding (IBM) as a joining technology of carbon fibre reinforced thermoplastic (CFR-TP) hollow profiles with metallic load introduction elements enables significant cycle time reduction by shortening of the process chain. As the composite part is joined to the metallic part during its consolidation process subsequent joining steps are omitted. In combination with a multi-scale structured load introduction element its form closure function enables to pass very high loads and is capable to achieve high degrees of material utilization. This paper first shows the process set-up utilizing thermoplastic tape braided preforms and two-staged press and internal hydro formed load introduction elements. Second focuses on heating technologies and process optimization. Aiming at cycle time reduction convection and induction heating in regard to the resulting product quality is inspected by photo micrographs and computer tomographic scans. Concluding remarks give final recommendations for the process design in regard to the structural design.

  13. Reduction of Aspergillus spp. and aflatoxins in peanut sauce processing by oil-less frying of chilli powder and retort processing.

    PubMed

    Farawahida, A H; Jinap, S; Nor-Khaizura, M A R; Samsudin, N I P

    2017-12-01

    Among the many roles played by small and medium enterprises (SMEs) in the food industry is the production of heritage foods such as peanut sauce. Unfortunately, the safety of peanut sauce is not always assured as the processing line is not controlled. Peanut sauce is usually made of peanuts and chilli, and these commodities are normally contaminated with Aspergillus spp. and aflatoxins (AFs). Hence, the objective of this study was to evaluate the practices related to reduction of AF hazard and the effect of interventions in peanut sauce processing. Peanut samples were collected from each step of peanut sauce processing from a small peanut sauce company according to four designs: (1) control; (2) oil-less frying of chilli powder; (3) addition of retort processing; and (4) combination of oil-less frying of chilli powder and retort processing. Oil-less frying of chilli powder (Design 2) reduced total AFs by 33-41%, retort processing (Design 3) reduced total AFs by 49%, while combination of these two thermal processes (Design 4) significantly reduced total AFs, by 57%. The present work demonstrated that Design 4 yielded the highest reduction of total AFs and is therefore recommended to be employed by SME companies.

  14. A modified oxic-settling-anaerobic activated sludge process using gravity thickening for excess sludge reduction

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Li, Shi-Yu; Jiang, Feng; Wu, Ke; Liu, Guang-Li; Lu, Hui; Chen, Guang-Hao

    2015-09-01

    Oxic-settling-anaerobic process (OSA) was known as a cost-effective way to reduce the excess sludge production with simple upgrade of conventional activated sludge process (CAS). A low oxidation-reduction potential (ORP) level was the key factor to sludge decay and lysis in the sludge holding tank of the OSA process. However, the ORP control with nitrogen purge or chemical dosing in the OSA process would induce extra expense and complicate the operation. Hence, in this study, a sludge holding tank using gravity thickening was applied to OSA process to reduce the excess sludge production without any ORP control. Results showed that the modified OSA process not only reduced the excess sludge production effectively but also improved the sludge settleability without affected the treatment capacity. The reduction of the excess sludge production in the modified OSA process resulted from interactions among lots of factors. The key element of the process was the gravity thickening sludge holding tank.

  15. Monte Carlo simulations of safeguards neutron counter for oxide reduction process feed material

    NASA Astrophysics Data System (ADS)

    Seo, Hee; Lee, Chaehun; Oh, Jong-Myeong; An, Su Jung; Ahn, Seong-Kyu; Park, Se-Hwan; Ku, Jeong-Hoe

    2016-10-01

    One of the options for spent-fuel management in Korea is pyroprocessing whose main process flow is the head-end process followed by oxide reduction, electrorefining, and electrowining. In the present study, a well-type passive neutron coincidence counter, namely, the ACP (Advanced spent fuel Conditioning Process) safeguards neutron counter (ASNC), was redesigned for safeguards of a hot-cell facility related to the oxide reduction process. To this end, first, the isotopic composition, gamma/neutron emission yield and energy spectrum of the feed material ( i.e., the UO2 porous pellet) were calculated using the OrigenARP code. Then, the proper thickness of the gammaray shield was determined, both by irradiation testing at a standard dosimetry laboratory and by MCNP6 simulations using the parameters obtained from the OrigenARP calculation. Finally, the neutron coincidence counter's calibration curve for 100- to 1000-g porous pellets, in consideration of the process batch size, was determined through simulations. Based on these simulation results, the neutron counter currently is under construction. In the near future, it will be installed in a hot cell and tested with spent fuel materials.

  16. Wet particle source identification and reduction using a new filter cleaning process

    NASA Astrophysics Data System (ADS)

    Umeda, Toru; Morita, Akihiko; Shimizu, Hideki; Tsuzuki, Shuichi

    2014-03-01

    Wet particle reduction during filter installation and start-up aligns closely with initiatives to reduce both chemical consumption and preventative maintenance time. The present study focuses on the effects of filter materials cleanliness on wet particle defectivity through evaluation of filters that have been treated with a new enhanced cleaning process focused on organic compounds reduction. Little difference in filter performance is observed between the two filter types at a size detection threshold of 60 nm, while clear differences are observed at that of 26 nm. It can be suggested that organic compounds can be identified as a potential source of wet particles. Pall recommends filters that have been treated with the special cleaning process for applications with a critical defect size of less than 60 nm. Standard filter products are capable to satisfy wet particle defect performance criteria in less critical lithography applications.

  17. Effect of fruit and vegetable processing on reduction of synthetic pyrethroid residues.

    PubMed

    Chauhan, Reena; Kumari, Beena; Rana, M K

    2014-01-01

    In this review, we emphasize that the advantages associated with applying pesticides to enhance agricultural productivity must be weighed against the possible health hazards arising from the appearance of toxic pesticide residues in food. First and foremost, pesticides should be handled and applied in compliance with good agricultural practices to minimize environmental or food commodity contamination.In developing countries, good agricultural practices are not fully abided by.When vegetables are produced in such countries, pesticides are applied or prospectively applied at each growth stage of the crop. Hence, contamination of vegetables and other food commodities occur. It is well known that processing of food derived from pesticide treated crop commodities can serve to reduce residues that reach consumers. Food safety can therefore partially be enhanced by employing suitable food processing techniques and appropriate storage periods, even in developing countries. Even common and simple household processing techniques for certain foods acquire significance as means to reduce the intake of harmful pesticide food residues.Pesticide residue levels in post-harvest raw agricultural commodities (RAC) are affected by the storage, handling and the processing steps they pass through, while being prepared for human consumption. The review of cogent literature presented in this article demonstrated differences among the pyrethroid insecticide residues present on or in foods, depending on how the RAC from which they came were processed for consumption. Peeling vegetables or fruit reduced pyrethroid residues the most (60-100% ), and juicing was nearly as effective in reducing residues (70-100% ). The least reduction occurred for foodstuffs that were only washed with tap water (I 0-70% ). Washing RACs with saline water and detergent was more effective(34-60%) in reducing residues than was simple washing under tap water. Freezing is also effective in reducing residue levels and

  18. Orbiter data reduction complex data processing requirements for the OFT mission evaluation team (level C)

    NASA Technical Reports Server (NTRS)

    1979-01-01

    This document addresses requirements for post-test data reduction in support of the Orbital Flight Tests (OFT) mission evaluation team, specifically those which are planned to be implemented in the ODRC (Orbiter Data Reduction Complex). Only those requirements which have been previously baselined by the Data Systems and Analysis Directorate configuration control board are included. This document serves as the control document between Institutional Data Systems Division and the Integration Division for OFT mission evaluation data processing requirements, and shall be the basis for detailed design of ODRC data processing systems.

  19. Effect of abiotic factors on the mercury reduction process by humic acids in aqueous systems

    USDA-ARS?s Scientific Manuscript database

    Mercury (Hg) in the environment can have serious toxic effects on a variety of living organisms, and is a pollutant of concern worldwide. The reduction of mercury from the toxic Hg2+ form to Hg0 is especially important. One pathway for this reduction to occur is through an abiotic process with humic...

  20. Data reduction complex analog-to-digital data processing requirements for onsite test facilities

    NASA Technical Reports Server (NTRS)

    Debbrecht, J. D.

    1976-01-01

    The analog to digital processing requirements of onsite test facilities are described. The source and medium of all input data to the Data Reduction Complex (DRC) and the destination and medium of all output products of the analog-to-digital processing are identified. Additionally, preliminary input and output data formats are presented along with the planned use of the output products.

  1. Reduction of Ochratoxin A in Oat Flakes by Twin-Screw Extrusion Processing.

    PubMed

    Lee, Hyun Jung; Dahal, Samjhana; Perez, Enrique Garcia; Kowalski, Ryan Joseph; Ganjyal, Girish M; Ryu, Dojin

    2017-10-01

    Ochratoxin A (OTA) is one of the most important mycotoxins owing to its widespread occurrence and toxicity, including nephrotoxicity and potential carcinogenicity to humans. OTA has been detected in a wide range of agricultural commodities, including cereal grains and their processed products. In particular, oat-based products show a higher incidence and level of contamination. Extrusion cooking is widely used in the manufacturing of breakfast cereals and snacks and may reduce mycotoxins to varying degrees. Hence, the effects of extrusion cooking on the stability of OTA in spiked (100 μg/kg) oat flake was investigated by using a laboratory-scale twin-screw extruder with a central composite design. Factors examined were moisture content (20, 25, and 30% dry weight basis), temperature (140, 160, and 180°C), screw speed (150, 200, and 250 rpm), and die size (1.5, 2, and 3 mm). Both nonextruded and extruded samples were analyzed for reductions of OTA by high-performance liquid chromatography, coupled with fluorescence detection. The percentage of reductions in OTA in the contaminated oat flakes upon extrusion processing were in the range of 0 to 28%. OTA was partially stable during extrusion, with only screw speed and die size having significant effect on reduction (P < 0.005). The highest reduction of 28% was achieved at 180°C, 20% moisture, 250 rpm screw speed, and a 3-mm die with 193 kJ/kg specific mechanical energy. According to the central composite design analyses, up to 28% of OTA can be reduced by a combination of 162°C, 30% moisture, and 221 rpm, with a 3-mm die.

  2. The Validation of Vapor Phase Hydrogen Peroxide Microbial Reduction for Planetary Protection and a Proposed Vacuum Process Specification

    NASA Technical Reports Server (NTRS)

    Chung, Shirley; Barengoltz, Jack; Kern, Roger; Koukol, Robert; Cash, Howard

    2006-01-01

    The Jet Propulsion Laboratory, in conjunction with the NASA Planetary Protection Officer, has selected the vapor phase hydrogen peroxide sterilization process for continued development as a NASA approved sterilization technique for spacecraft subsystems and systems. The goal is to include this technique, with an appropriate specification, in NPR 8020.12C as a low temperature complementary technique to the dry heat sterilization process.To meet microbial reduction requirements for all Mars in-situ life detection and sample return missions, various planetary spacecraft subsystems will have to be exposed to a qualified sterilization process. This process could be the elevated temperature dry heat sterilization process (115 C for 40 hours) which was used to sterilize the Viking lander spacecraft. However, with utilization of such elements as highly sophisticated electronics and sensors in modern spacecraft, this process presents significant materials challenges and is thus an undesirable bioburden reduction method to design engineers. The objective of this work is to introduce vapor hydrogen peroxide (VHP) as an alternative to dry heat microbial reduction to meet planetary protection requirements.The VHP process is widely used by the medical industry to sterilize surgical instruments and biomedical devices, but high doses of VHP may degrade the performance of flight hardware, or compromise material properties. Our goal for this study was to determine the minimum VHP process conditions to achieve microbial reduction levels acceptable for planetary protection.

  3. Prevention and harm reduction for chemical dependency: a process perspective.

    PubMed

    DiClemente, C C

    1999-06-01

    Clinical psychology is often on the periphery of treatment and prevention efforts to stop substance abuse and dependence. This article describes the current status of prevention research and practice, outlines a process perspective on the initiation and cessation of drug use and abuse, and offers some new ideas about how psychology can and should become involved in the prevention of chemical dependency. Psychologists are faced with the precursors and consequences of chemical dependency on a daily basis. With improved training and increased awareness, and aided by a process perspective, psychology and psychologists can play an important role in preventing the onset of chemical dependency, creating early interventions to stop the process of initiation, and becoming more involved in treatment and harm-reduction efforts. Psychologists have the basic training and the biopsychosocial orientation that could make them effective agents for primary, secondary, and tertiary prevention of chemical dependency.

  4. Effects of dissolved oxygen on performance and microbial community structure in a micro-aerobic hydrolysis sludge in situ reduction process.

    PubMed

    Niu, Tianhao; Zhou, Zhen; Shen, Xuelian; Qiao, Weimin; Jiang, Lu-Man; Pan, Wei; Zhou, Jijun

    2016-03-01

    A sludge process reduction activated sludge (SPRAS), with a sludge process reduction module composed of a micro-aerobic tank and a settler positioned before conventional activated sludge process, showed good performance of pollutant removal and sludge reduction. Two SPRAS systems were operated to investigate effects of micro-aeration on sludge reduction performance and microbial community structure. When dissolved oxygen (DO) concentration in the micro-aerobic tank decreased from 2.5 (SPH) to 0.5 (SPL) mg/L, the sludge reduction efficiency increased from 42.9% to 68.3%. Compared to SPH, activated sludge in SPL showed higher contents of extracellular polymeric substances and dissolved organic matter. Destabilization of floc structure in the settler, and cell lysis in the sludge process reduction module were two major reasons for sludge reduction. Illumina-MiSeq sequencing showed that microbial diversity decreased under high DO concentration. Proteobacteria, Bacteroidetes and Chloroflexi were the most abundant phyla in the SPRAS. Specific comparisons down to the class and genus level showed that fermentative, predatory and slow-growing bacteria in SPL community were more abundant than in SPH. The results revealed that micro-aeration in the SPRAS improved hydrolysis efficiency and enriched fermentative and predatory bacteria responsible for sludge reduction. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. The Effect of Carbonaceous Reductant Selection on Chromite Pre-reduction

    NASA Astrophysics Data System (ADS)

    Kleynhans, E. L. J.; Beukes, J. P.; Van Zyl, P. G.; Bunt, J. R.; Nkosi, N. S. B.; Venter, M.

    2017-04-01

    Ferrochrome (FeCr) production is an energy-intensive process. Currently, the pelletized chromite pre-reduction process, also referred to as solid-state reduction of chromite, is most likely the FeCr production process with the lowest specific electricity consumption, i.e., MWh/t FeCr produced. In this study, the effects of carbonaceous reductant selection on chromite pre-reduction and cured pellet strength were investigated. Multiple linear regression analysis was employed to evaluate the effect of reductant characteristics on the aforementioned two parameters. This yielded mathematical solutions that can be used by FeCr producers to select reductants more optimally in future. Additionally, the results indicated that hydrogen (H)- (24 pct) and volatile content (45.8 pct) were the most significant contributors for predicting variance in pre-reduction and compressive strength, respectively. The role of H within this context is postulated to be linked to the ability of a reductant to release H that can induce reduction. Therefore, contrary to the current operational selection criteria, the authors believe that thermally untreated reductants ( e.g., anthracite, as opposed to coke or char), with volatile contents close to the currently applied specification (to ensure pellet strength), would be optimal, since it would maximize H content that would enhance pre-reduction.

  6. Interim glycol flowsheet reduction/oxidation (redox) model for the Defense Waste Processing Facility (DWPF)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jantzen, C. M.; Williams, M. S.; Zamecnik, J. R.

    Control of the REDuction/OXidation (REDOX) state of glasses containing high concentrations of transition metals, such as High Level Waste (HLW) glasses, is critical in order to eliminate processing difficulties caused by overly reduced or overly oxidized melts. Operation of a HLW melter at Fe +2/ΣFe ratios of between 0.09 and 0.33, a range which is not overly oxidizing or overly reducing, helps retain radionuclides in the melt, i.e. long-lived radioactive 99Tc species in the less volatile reduced Tc 4+ state, 104Ru in the melt as reduced Ru +4 state as insoluble RuO 2, and hazardous volatile Cr 6+ in themore » less soluble and less volatile Cr +3 state in the glass. The melter REDOX control balances the oxidants and reductants from the feed and from processing additives such as antifoam. Currently, the Defense Waste Processing Facility (DWPF) is running a formic acid-nitric acid (FN) flowsheet where formic acid is the main reductant and nitric acid is the main oxidant. During decomposition formate and formic acid releases H 2 gas which requires close control of the melter vapor space flammability. A switch to a nitric acid-glycolic acid (GN) flowsheet is desired as the glycolic acid flowsheet releases considerably less H 2 gas upon decomposition. This would greatly simplify DWPF processing. Development of an EE term for glycolic acid in the GN flowsheet is documented in this study.« less

  7. Study on emission characteristics and reduction strategy of nitrous oxide during wastewater treatment by different processes.

    PubMed

    Sun, Shichang; Bao, Zhiyuan; Sun, Dezhi

    2015-03-01

    Given the inexorable increase in global wastewater treatment, increasing amounts of nitrous oxide are expected to be emitted from wastewater treatment plants and released to the atmosphere. It has become imperative to study the emission and control of nitrous oxide in the various wastewater treatment processes currently in use. In the present investigation, the emission characteristics and the factors affecting the release of nitrous oxide were studied via full- and pilot-scale experiments in anoxic-oxic, sequencing batch reactor and oxidation ditch processes. We propose an optimal treatment process and relative strategy for nitrous oxide reduction. Our results show that both the bio-nitrifying and bio-denitrifying treatment units in wastewater treatment plants are the predominant sites for nitrous oxide production in each process, while the aerated treatment units are the critical sources for nitrous oxide emission. Compared with the emission of nitrous oxide from the anoxic-oxic (1.37% of N-influent) and sequencing batch reactor (2.69% of N-influent) processes, much less nitrous oxide (0.25% of N-influent) is emitted from the oxidation ditch process, which we determined as the optimal wastewater treatment process for nitrous oxide reduction, given the current technologies. Nitrous oxide emissions differed with various operating parameters. Controlling the dissolved oxygen concentration at a proper level during nitrification and denitrification and enhancing the utilization rate of organic carbon in the influent for denitrification are the two critical methods for nitrous oxide reduction in the various processes considered.

  8. Improving Pathogen Reduction by Chlorine Wash Prior to Cutting in Fresh-Cut Processing

    USDA-ARS?s Scientific Manuscript database

    Introduction: Currently, most fresh-cut processing facilities in the United States use chlorinated water or other sanitizer solutions for microbial reduction after lettuce is cut. Freshly cut lettuce releases significant amounts of organic matter that negatively impacts the effectiveness of chlorine...

  9. Modeling and reduction with applications to semiconductor processing

    NASA Astrophysics Data System (ADS)

    Newman, Andrew Joseph

    This thesis consists of several somewhat distinct but connected parts, with an underlying motivation in problems pertaining to control and optimization of semiconductor processing. The first part (Chapters 3 and 4) addresses problems in model reduction for nonlinear state-space control systems. In 1993, Scherpen generalized the balanced truncation method to the nonlinear setting. However, the Scherpen procedure is not easily computable and has not yet been applied in practice. We offer a method for computing a working approximation to the controllability energy function, one of the main objects involved in the method. Moreover, we show that for a class of second-order mechanical systems with dissipation, under certain conditions related to the dissipation, an exact formula for the controllability function can be derived. We then present an algorithm for a numerical implementation of the Morse-Palais lemma, which produces a local coordinate transformation under which a real-valued function with a non-degenerate critical point is quadratic on a neighborhood of the critical point. Application of the algorithm to the controllabilty function plays a key role in computing the balanced representation. We then apply our methods and algorithms to derive balanced realizations for nonlinear state-space models of two example mechanical systems: a simple pendulum and a double pendulum. The second part (Chapter 5) deals with modeling of rapid thermal chemical vapor deposition (RTCVD) for growth of silicon thin films, via first-principles and empirical analysis. We develop detailed process-equipment models and study the factors that influence deposition uniformity, such as temperature, pressure, and precursor gas flow rates, through analysis of experimental and simulation results. We demonstrate that temperature uniformity does not guarantee deposition thickness uniformity in a particular commercial RTCVD reactor of interest. In the third part (Chapter 6) we continue the modeling

  10. Effects of antibody disulfide bond reduction on purification process performance and final drug substance stability

    PubMed Central

    Russell, Brian; Yang, Yanhong; Handlogten, Michael; Hudak, Suzanne; Cao, Mingyan; Wang, Jihong; Robbins, David; Ahuja, Sanjeev; Zhu, Min

    2017-01-01

    ABSTRACT Antibody disulfide bond reduction during monoclonal antibody (mAb) production is a phenomenon that has been attributed to the reducing enzymes from CHO cells acting on the mAb during the harvest process. However, the impact of antibody reduction on the downstream purification process has not been studied. During the production of an IgG2 mAb, antibody reduction was observed in the harvested cell culture fluid (HCCF), resulting in high fragment levels. In addition, aggregate levels increased during the low pH treatment step in the purification process. A correlation between the level of free thiol in the HCCF (as a result of antibody reduction) and aggregation during the low pH step was established, wherein higher levels of free thiol in the starting sample resulted in increased levels of aggregates during low pH treatment. The elevated levels of free thiol were not reduced over the course of purification, resulting in carry‐over of high free thiol content into the formulated drug substance. When the drug substance with high free thiols was monitored for product degradation at room temperature and 2–8°C, faster rates of aggregation were observed compared to the drug substance generated from HCCF that was purified immediately after harvest. Further, when antibody reduction mitigations (e.g., chilling, aeration, and addition of cystine) were applied, HCCF could be held for an extended period of time while providing the same product quality/stability as material that had been purified immediately after harvest. Biotechnol. Bioeng. 2017;114: 1264–1274. © 2017 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals Inc. PMID:28186329

  11. LCD motion blur reduction: a signal processing approach.

    PubMed

    Har-Noy, Shay; Nguyen, Truong Q

    2008-02-01

    Liquid crystal displays (LCDs) have shown great promise in the consumer market for their use as both computer and television displays. Despite their many advantages, the inherent sample-and-hold nature of LCD image formation results in a phenomenon known as motion blur. In this work, we develop a method for motion blur reduction using the Richardson-Lucy deconvolution algorithm in concert with motion vector information from the scene. We further refine our approach by introducing a perceptual significance metric that allows us to weight the amount of processing performed on different regions in the image. In addition, we analyze the role of motion vector errors in the quality of our resulting image. Perceptual tests indicate that our algorithm reduces the amount of perceivable motion blur in LCDs.

  12. Evaluation of a biological wastewater treatment system combining an OSA process with ultrasound for sludge reduction.

    PubMed

    Romero-Pareja, P M; Aragon, C A; Quiroga, J M; Coello, M D

    2017-05-01

    Sludge production is an undesirable by-product of biological wastewater treatment. The oxic-settling-anaerobic (OSA) process constitutes one of the most promising techniques for reducing the sludge produced at the treatment plant without negative consequences for its overall performance. In the present study, the OSA process is applied in combination with ultrasound treatment, a lysis technique, in a lab-scale wastewater treatment plant to assess whether sludge reduction is enhanced as a result of mechanical treatment. Reported sludge reductions of 45.72% and 78.56% were obtained for the two regimes of combined treatment tested in this study during two respective stages: UO1 and UO2. During the UO1 stage, the general performance and nutrient removal improved, obtaining 47.28% TN removal versus 21.95% in the conventional stage. However, the performance of the system was seriously damaged during the UO2 stage. Increases in dehydrogenase and protease activities were observed during both stages. The advantages of the combined process are not necessarily economic, but operational, as US treatment acts as contributing factor in the OSA process, inducing mechanisms that lead to sludge reduction in the OSA process and improving performance parameters. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Reaction engineering for materials processing in space: Reduction of ilmenite by hydrogen and carbon monoxide

    NASA Technical Reports Server (NTRS)

    Zhao, Y.; Shadman, F.

    1991-01-01

    Oxygen is a consumable material which needs to be produced continuously in most space missions. Its use for propulsion as well as life support makes oxygen one of the largest volume chemicals to be produced in space. Production of oxygen from lunar materials is of particular interest and is very attractive possibility. The kinetics and mechanism of reduction of ilmenite by carbon monoxide and hydrogen at 800 to 1100 C were investigated. The temporal profiles of conversion for carbon monoxide have a sigmoidal shape and indicate the presence of three different stages (induction, acceleration, and deceleration) during the reduction reaction. The apparent activation energy decreases from 18 kcal/mole at 10 percent conversion to 10 kcal/mole at 50 percent conversion. The reaction is first order with respect to carbon monoxide under the experimental conditions studied. Both SEM and EDX analysis show that the diffusion of Fe product away from the reaction front and through the TiO2 phase, followed by the nucleation and growth of a separate Fe phase are important steps affecting the process kinetics. The results from hydrogen reduction show that the mechanism of ilmenite reduction by hydrogen is similar to that by carbon monoxide. However, the titanium dioxide can be further reduced by hydrogen at 800 to 1000 C. The detailed comparison and theoretical modeling of both reduction processes is presented.

  14. Medication waste reduction in pediatric pharmacy batch processes.

    PubMed

    Toerper, Matthew F; Veltri, Michael A; Hamrock, Eric; Mollenkopf, Nicole L; Holt, Kristen; Levin, Scott

    2014-04-01

    To inform pediatric cart-fill batch scheduling for reductions in pharmaceutical waste using a case study and simulation analysis. A pre and post intervention and simulation analysis was conducted during 3 months at a 205-bed children's center. An algorithm was developed to detect wasted medication based on time-stamped computerized provider order entry information. The algorithm was used to quantify pharmaceutical waste and associated costs for both preintervention (1 batch per day) and postintervention (3 batches per day) schedules. Further, simulation was used to systematically test 108 batch schedules outlining general characteristics that have an impact on the likelihood for waste. Switching from a 1-batch-per-day to a 3-batch-per-day schedule resulted in a 31.3% decrease in pharmaceutical waste (28.7% to 19.7%) and annual cost savings of $183,380. Simulation results demonstrate how increasing batch frequency facilitates a more just-in-time process that reduces waste. The most substantial gains are realized by shifting from a schedule of 1 batch per day to at least 2 batches per day. The simulation exhibits how waste reduction is also achievable by avoiding batch preparation during daily time periods where medication administration or medication discontinuations are frequent. Last, the simulation was used to show how reducing batch preparation time per batch provides some, albeit minimal, opportunity to decrease waste. The case study and simulation analysis demonstrate characteristics of batch scheduling that may support pediatric pharmacy managers in redesign toward minimizing pharmaceutical waste.

  15. Westinghouse Modular Grinding Process - Enhancement of Volume Reduction for Hot Resin Supercompaction - 13491

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fehrmann, Henning; Aign, Joerg

    2013-07-01

    In nuclear power plants (NPP) ion exchange (IX) resins are used in several systems for water treatment. Spent resins can contain a significant amount of contaminates which makes treatment for disposal of spent resins mandatory. Several treatment processes are available such as direct immobilization with technologies like cementation, bitumisation, polymer solidification or usage of a high integrity container (HIC). These technologies usually come with a significant increase in final waste volume. The Hot Resin Supercompaction (HRSC) is a thermal treatment process which reduces the resin waste volume significantly. For a mixture of powdered and bead resins the HRSC process hasmore » demonstrated a volume reduction of up to 75 % [1]. For bead resins only the HRSC process is challenging because the bead resins compaction properties are unfavorable. The bead resin material does not form a solid block after compaction and shows a high spring back effect. The volume reduction of bead resins is not as good as for the mixture described in [1]. The compaction properties of bead resin waste can be significantly improved by grinding the beads to powder. The grinding also eliminates the need for a powder additive.Westinghouse has developed a modular grinding process to grind the bead resin to powder. The developed process requires no circulation of resins and enables a selective adjustment of particle size and distribution to achieve optimal results in the HRSC or in any other following process. A special grinding tool setup is use to minimize maintenance and radiation exposure to personnel. (authors)« less

  16. Optimization of Ozonation Process for the Reduction of Excess Sludge Production from Activated Sludge Process of Sago Industry Wastewater Using Central Composite Design

    PubMed Central

    Subha, B.; Muthukumar, M.

    2012-01-01

    Sago industries effluent containing large amounts of organic content produced excess sludge which is a serious problem in wastewater treatment. In this study ozonation has been employed for the reduction of excess sludge production in activated sludge process. Central composite design is used to study the effect of ozone treatment for the reduction of excess sludge production in sago effluent and to optimise the variables such as pH, ozonation time, and retention time. ANOVA showed that the coefficient determination value (R 2) of VSS and COD reduction were 0.9689 and 0.8838, respectively. VSS reduction (81%) was achieved at acidic pH 6.9, 12 minutes ozonation, and retention time of 10 days. COD reduction (87%) was achieved at acidic pH 6.7, 8 minutes of ozonation time, and retention time of 6 days. Low ozonation time and high retention time influence maximum sludge reduction, whereas low ozonation time with low retention time was effective for COD reduction. PMID:22593666

  17. Spectral OCT with speckle contrast reduction for evaluation of the healing process after PRK and transepithelial PRK

    PubMed Central

    Kaluzny, Bartlomiej J.; Szkulmowski, Maciej; Bukowska, Danuta M.; Wojtkowski, Maciej

    2014-01-01

    We evaluate Spectral OCT (SOCT) with a speckle contrast reduction technique using resonant scanner for assessment of corneal surface changes after excimer laser photorefractive keratectomy (PRK) and we compare healing process between conventional PRK and transepithelial PRK. The measurements were performed before and after the surgery. Obtained results show that SOCT with a resonant scanner speckle contrast reduction is capable of providing information regarding the healing process after PRK. The main difference between the healing processes of PRK and TransPRK, assessed by SOCT, was the time to cover the stroma with epithelium, which was shorter in the TransPRK group. PMID:24761291

  18. Spectral OCT with speckle contrast reduction for evaluation of the healing process after PRK and transepithelial PRK.

    PubMed

    Kaluzny, Bartlomiej J; Szkulmowski, Maciej; Bukowska, Danuta M; Wojtkowski, Maciej

    2014-04-01

    We evaluate Spectral OCT (SOCT) with a speckle contrast reduction technique using resonant scanner for assessment of corneal surface changes after excimer laser photorefractive keratectomy (PRK) and we compare healing process between conventional PRK and transepithelial PRK. The measurements were performed before and after the surgery. Obtained results show that SOCT with a resonant scanner speckle contrast reduction is capable of providing information regarding the healing process after PRK. The main difference between the healing processes of PRK and TransPRK, assessed by SOCT, was the time to cover the stroma with epithelium, which was shorter in the TransPRK group.

  19. Dissimilatory nitrate reduction processes in sediments of urban river networks: Spatiotemporal variations and environmental implications.

    PubMed

    Cheng, Lv; Li, Xiaofei; Lin, Xianbiao; Hou, Lijun; Liu, Min; Li, Ye; Liu, Sai; Hu, Xiaoting

    2016-12-01

    Urbanizations have increased the loadings of reactive nitrogen in urban riverine environments. However, limited information about dissimilatory nitrate reduction processes and associated contributions to nitrogen removal is available for urban riverine environments. In this study, sediment slurry experiments were conducted with nitrogen isotope-tracing technique to investigate the potential rates of denitrification, anaerobic ammonium oxidation (anammox) and dissimilatory nitrate reduction to ammonium (DNRA) and their contributions to nitrate reduction in sediments of urban river networks, Shanghai. The potential rates of denitrification, anammox and DNRA measured in the study area ranged from 0.193 to 98.7 nmol N g -1  h -1 dry weight (dw), 0.0387-23.7 nmol N g -1  h -1  dw and 0-10.3 nmol N g -1  h -1  dw, respectively. Denitrification and DNRA rates were higher in summer than in winter, while anammox rates were greater in winter than in summer for most sites. Dissolved oxygen, total organic carbon, nitrate, ammonium, sulfide, Fe(II) and Fe(III) were found to have significant influence on these nitrate reduction processes. Denitrification contributed 11.5-99.5%% to total nitrate reduction, as compared to 0.343-81.6% for anammox and 0-52.3% for DNRA. It is estimated that nitrogen loss of approximately 1.33 × 10 5  t N year -1 was linked to both denitrification and anammox processes, which accounted for about 20.1% of total inorganic nitrogen transported annually into the urban river networks of Shanghai. Overall, these results show the potential importance of denitrification and anammox in nitrogen removal and provide new insight into the mechanisms of nitrogen cycles in urban riverine environments. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. The Reduction of Lunar Regolith by Carbothermal Processing Using Methane

    NASA Technical Reports Server (NTRS)

    Balasubramaniam, R.; Hegde, U.; Gokoglu, S.

    2010-01-01

    The processing of lunar regolith for the production of oxygen is a key component of the In-Situ Resource Utilization plans Currently being developed by NASA. In the carbothermal process, a portion of the surface of the regolith in a container is heated by exposure to a heat source so that a small zone of molten regolith is established. A continuous flow of methane is maintained over the molten regolith zone. In this paper, we discuss the development of a chemical conversion model of the carbothermal process to predict the rate of production of carbon monoxide. Our model is based on a mechanism where methane pyrolyzes when it comes in contact with the surface of the hot molten regolith to form solid carbon and hydrogen gas. Carbon is deposited on the surface of the melt, and hydrogen is released into the gas stream above the melt surface. We assume that the deposited carbon mixes in the molten regolith and reacts with metal oxides in a reduction reaction by which gaseous carbon monoxide is liberated. Carbon monoxide bubbles through the melt and is released into the gas stream. It is further processed downstream to ultimately produce oxygen.

  1. The Reduction of Lunar Regolith by Carbothermal Processing Using Methane

    NASA Technical Reports Server (NTRS)

    Balasubramaniam, R.; Gokoglu, S. A.; Hegde, U.

    2010-01-01

    The processing of lunar regolith for the production of oxygen is a key component of the In-Situ Resource Utilization plans currently being developed by NASA. In the carbothermal process, a portion of the surface of the regolith in a container is heated by exposure to a heat source so that a small zone of molten regolith is established. A continuous flow of methane is maintained over the molten regolith zone. In this paper, we discuss the development of a chemical conversion model of the carbothermal process to predict the rate of production of carbon monoxide. Our model is based on a mechanism where methane pyrolyzes when it comes in contact with the surface of the hot molten regolith to form solid carbon and hydrogen gas. Carbon is deposited on the surface of the melt, and hydrogen is released into the gas stream above the melt surface. We assume that the deposited carbon mixes in the molten regolith and reacts with metal oxides in a reduction reaction by which gaseous carbon monoxide is liberated. Carbon monoxide bubbles through the melt and is released into the gas stream. It is further processed downstream to ultimately produce oxygen.

  2. Corrosion Testing of Monofrax K-3 Refractory in Defense Waste Processing Facility (DWPF) Alternate Reductant Feeds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Williams, M.; Jantzen, C.; Burket, P.

    The Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) uses a combination of reductants and oxidants while converting high level waste (HLW) to a borosilicate waste form. A reducing flowsheet is maintained to retain radionuclides in their reduced oxidation states which promotes their incorporation into borosilicate glass. For the last 20 years of processing, the DWPF has used formic acid as the main reductant and nitric acid as the main oxidant. During reaction in the Chemical Process Cell (CPC), formate and formic acid release measurably significant H 2 gas which requires monitoring of certain vessel’s vapor spaces.more » A switch to a nitric acid-glycolic acid (NG) flowsheet from the nitric-formic (NF) flowsheet is desired as the NG flowsheet releases considerably less H 2 gas upon decomposition. This would greatly simplify DWPF processing from a safety standpoint as close monitoring of the H 2 gas concentration could become less critical. In terms of the waste glass melter vapor space flammability, the switch from the NF flowsheet to the NG flowsheet showed a reduction of H 2 gas production from the vitrification process as well. Due to the positive impact of the switch to glycolic acid determined on the flammability issues, evaluation of the other impacts of glycolic acid on the facility must be examined.« less

  3. Medication Waste Reduction in Pediatric Pharmacy Batch Processes

    PubMed Central

    Veltri, Michael A.; Hamrock, Eric; Mollenkopf, Nicole L.; Holt, Kristen; Levin, Scott

    2014-01-01

    OBJECTIVES: To inform pediatric cart-fill batch scheduling for reductions in pharmaceutical waste using a case study and simulation analysis. METHODS: A pre and post intervention and simulation analysis was conducted during 3 months at a 205-bed children's center. An algorithm was developed to detect wasted medication based on time-stamped computerized provider order entry information. The algorithm was used to quantify pharmaceutical waste and associated costs for both preintervention (1 batch per day) and postintervention (3 batches per day) schedules. Further, simulation was used to systematically test 108 batch schedules outlining general characteristics that have an impact on the likelihood for waste. RESULTS: Switching from a 1-batch-per-day to a 3-batch-per-day schedule resulted in a 31.3% decrease in pharmaceutical waste (28.7% to 19.7%) and annual cost savings of $183,380. Simulation results demonstrate how increasing batch frequency facilitates a more just-in-time process that reduces waste. The most substantial gains are realized by shifting from a schedule of 1 batch per day to at least 2 batches per day. The simulation exhibits how waste reduction is also achievable by avoiding batch preparation during daily time periods where medication administration or medication discontinuations are frequent. Last, the simulation was used to show how reducing batch preparation time per batch provides some, albeit minimal, opportunity to decrease waste. CONCLUSIONS: The case study and simulation analysis demonstrate characteristics of batch scheduling that may support pediatric pharmacy managers in redesign toward minimizing pharmaceutical waste. PMID:25024671

  4. Reducing uncertainty in estimating virus reduction by advanced water treatment processes.

    PubMed

    Gerba, Charles P; Betancourt, Walter Q; Kitajima, Masaaki; Rock, Channah M

    2018-04-15

    Treatment of wastewater for potable reuse requires the reduction of enteric viruses to levels that pose no significant risk to human health. Advanced water treatment trains (e.g., chemical clarification, reverse osmosis, ultrafiltration, advanced oxidation) have been developed to provide reductions of viruses to differing levels of regulatory control depending upon the levels of human exposure and associated health risks. Importance in any assessment is information on the concentration and types of viruses in the untreated wastewater, as well as the degree of removal by each treatment process. However, it is critical that the uncertainty associated with virus concentration and removal or inactivation by wastewater treatment be understood to improve these estimates and identifying research needs. We reviewed the critically literature to assess to identify uncertainty in these estimates. Biological diversity within families and genera of viruses (e.g. enteroviruses, rotaviruses, adenoviruses, reoviruses, noroviruses) and specific virus types (e.g. serotypes or genotypes) creates the greatest uncertainty. These aspects affect the methods for detection and quantification of viruses and anticipated removal efficiency by treatment processes. Approaches to reduce uncertainty may include; 1) inclusion of a virus indicator for assessing efficiency of virus concentration and detection by molecular methods for each sample, 2) use of viruses most resistant to individual treatment processes (e.g. adenoviruses for UV light disinfection and reoviruses for chlorination), 3) data on ratio of virion or genome copies to infectivity in untreated wastewater, and 4) assessment of virus removal at field scale treatment systems to verify laboratory and pilot plant data for virus removal. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Pyrolysis Treatment of Chromite Ore Processing Residue by Biomass: Cellulose Pyrolysis and Cr(VI) Reduction Behavior.

    PubMed

    Zhang, Da-Lei; Zhang, Mei-Yi; Zhang, Chu-Hui; Sun, Ying-Jie; Sun, Xiao; Yuan, Xian-Zheng

    2016-03-15

    The pyrolysis treatment with biomass is a promising technology for the remediation of chromite-ore-processing residue (COPR). However, the mechanism of this process is still unclear. In this study, the behavior of pyrolysis reduction of Cr(VI) by cellulose, the main component of biomass, was elucidated. The results showed that the volatile fraction (VF) of cellulose, ie. gas and tar, was responsible for Cr(VI) reduction. All organic compounds, as well as CO and H2 in VF, potentially reduced Cr(VI). X-ray absorption near-edge structure (XANES) spectroscopy and extended X-ray absorption fine-structure (EXAFS) spectroscopy confirmed the reduction of Cr(VI) to Cr(III) and the formation of amorphous Cr2O3. The remnant Cr(VI) content in COPR can be reduced below the detection limit (2 mg/kg) by the reduction of COPR particle and extension of reaction time between VF and COPR. This study provided a deep insight on the co-pyrolysis of cellulose with Cr(VI) in COPR and an ideal approach by which to characterize and optimize the pyrolysis treatment for COPR by other organics.

  6. Reduction of Environmental Listeria Using Gaseous Ozone in a Cheese Processing Facility.

    PubMed

    Eglezos, Sofroni; Dykes, Gary A

    2018-05-01

    A cheese processing facility seeking to reduce environmental Listeria colonization initiated a regime of ozonation across all production areas as an adjunct to its sanitation regimes. A total of 360 environmental samples from the facility were tested for Listeria over a 12-month period. A total of 15 areas before and 15 areas after ozonation were tested. Listeria isolations were significantly ( P < 0.001) reduced from 15.0% in the preozonation samples to 1.67% in the postozonation samples in all areas. No deleterious effects of ozonation were noted on the wall paneling, seals, synthetic floors, or cheese processing equipment. The ozonation regime was readily incorporated by sanitation staff into the existing good manufacturing practice program. The application of ozone may result in a significant reduction in the prevalence of Listeria in food processing facilities.

  7. The anaerobic degradation of organic matter in Danish coastal sediments - Iron reduction, manganese reduction, and sulfate reduction

    NASA Technical Reports Server (NTRS)

    Canfield, Donald E.; Thamdrup, BO; Hansen, Jens W.

    1993-01-01

    A combination of porewater and solid phase analysis as well as a series of sediment incubations are used to quantify organic carbon oxidation by dissimilatory Fe reduction, Mn reduction, and sulfate reduction, in sediments from the Skagerrak (located off the northeast coast of Jutland, Denmark). Solid phase data are integrated with incubation results to define the zones of the various oxidation processes. At S(9), surface Mn enrichments of up to 3.5 wt pct were found, and with such a ready source of Mn, dissimilatory Mn reduction was the only significant anaerobic process of carbon oxidation in the surface 10 cm of the sediment. At S(4) and S(6), active Mn reduction occurred; however, most of the Mn reduction may have resulted from the oxidation of acid volatile sulfides and Fe(2+) rather than by a dissimilatory sulfate. Dissolved Mn(2+) was found to completely adsorb onto sediment containing fully oxidized Mn oxides.

  8. Magnetic losses reduction in grain oriented silicon steel by pulse and continuous fiber laser processing

    NASA Astrophysics Data System (ADS)

    Petryshynets, Ivan; Kováč, František; Puchý, Viktor; Šebek, Martin; Füzer, Ján; Kollár, Peter

    2018-04-01

    The present paper shows the impact of different laser scribing conditions on possible reduction of magnetic losses in grain oriented electrical steel sheets. The experimental Fe-3%Si steel was taken from industrial line after final box annealing. The surface of investigated steel was subjected to fiber laser processing using both pulse and continuous scribing regimes in order to generate residual thermal stresses inducing the magnetic domains structure refinement. The magnetic losses of experimental samples before and after individual laser scribing regimes were tested in AC magnetic field with 50Hz frequency and induction of 1.5T. The most significant magnetic losses reduction of 38% was obtained at optimized conditions of continuous laser scribing regime. A semi quantitative relationship has been found between the domain patterns and the used fiber laser processing.

  9. 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. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Optimization of palm oil physical refining process for reduction of 3-monochloropropane-1,2-diol (3-MCPD) ester formation.

    PubMed

    Zulkurnain, Musfirah; Lai, Oi Ming; Tan, Soo Choon; Abdul Latip, Razam; Tan, Chin Ping

    2013-04-03

    The reduction of 3-monochloropropane-1,2-diol (3-MCPD) ester formation in refined palm oil was achieved by incorporation of additional processing steps in the physical refining process to remove chloroester precursors prior to the deodorization step. The modified refining process was optimized for the least 3-MCPD ester formation and acceptable refined palm oil quality using response surface methodology (RSM) with five processing parameters: water dosage, phosphoric acid dosage, degumming temperature, activated clay dosage, and deodorization temperature. The removal of chloroester precursors was largely accomplished by increasing the water dosage, while the reduction of 3-MCPD esters was a compromise in oxidative stability and color of the refined palm oil because some factors such as acid dosage, degumming temperature, and deodorization temperature showed contradictory effects. The optimization resulted in 87.2% reduction of 3-MCPD esters from 2.9 mg/kg in the conventional refining process to 0.4 mg/kg, with color and oil stability index values of 2.4 R and 14.3 h, respectively.

  11. Compensation for the signal processing characteristics of ultrasound B-mode scanners in adaptive speckle reduction.

    PubMed

    Crawford, D C; Bell, D S; Bamber, J C

    1993-01-01

    A systematic method to compensate for nonlinear amplification of individual ultrasound B-scanners has been investigated in order to optimise performance of an adaptive speckle reduction (ASR) filter for a wide range of clinical ultrasonic imaging equipment. Three potential methods have been investigated: (1) a method involving an appropriate selection of the speckle recognition feature was successful when the scanner signal processing executes simple logarithmic compressions; (2) an inverse transform (decompression) of the B-mode image was effective in correcting for the measured characteristics of image data compression when the algorithm was implemented in full floating point arithmetic; (3) characterising the behaviour of the statistical speckle recognition feature under conditions of speckle noise was found to be the method of choice for implementation of the adaptive speckle reduction algorithm in limited precision integer arithmetic. In this example, the statistical features of variance and mean were investigated. The third method may be implemented on commercially available fast image processing hardware and is also better suited for transfer into dedicated hardware to facilitate real-time adaptive speckle reduction. A systematic method is described for obtaining ASR calibration data from B-mode images of a speckle producing phantom.

  12. Reduction-melting combined with a Na₂CO₃ flux recycling process for lead recovery from cathode ray tube funnel glass.

    PubMed

    Okada, Takashi; Yonezawa, Susumu

    2014-08-01

    With large quantity of flux (Na2CO3), lead can be recovered from the funnel glass of waste cathode-ray tubes via reduction-melting at 1000°C. To reduce flux cost, a technique to recover added flux from the generated oxide phase is also important in order to recycle the flux recovered from the reduction-melting process. In this study, the phase separation of sodium and the crystallization of water-soluble sodium silicates were induced after the reduction-melting process to enhance the leachability of sodium in the oxide phase and to extract the sodium from the phase for the recovery of Na2CO3 as flux. A reductive atmosphere promoted the phase separation and crystallization, and the leachability of sodium from the oxide phase was enhanced. The optimum temperature and treatment time for increasing the leachability were 700°C and 2h, respectively. After treatment, more than 90% of the sodium in the oxide phase was extracted in water. NaHCO3 can be recovered by carbonization of the solution containing sodium ions using carbon dioxide gas, decomposed to Na2CO3 at 50°C and recycled for use in the reduction-melting process. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Reduction of potassium content of green bean pods and chard by culinary processing. Tools for chronic kidney disease.

    PubMed

    Martínez-Pineda, Montserrat; Yagüe-Ruiz, Cristina; Caverni-Muñoz, Alberto; Vercet-Tormo, Antonio

    2016-01-01

    In order to prevent a possible hyperkalemia, chronic renal patients, especially in advanced stages, must follow a low potassium diet. So dietary guidelines for chronic kidney disease recommend limiting the consumption of many vegetables, as well as to apply laborious culinary techniques to maximize the reduction of potassium. The aim of this work is to analyze potassium content from several vegetable, fresh products, frozen and preserved, as well as check and compare the effectiveness in potassium reduction of different culinary processes, some of them recommended in dietary guidelines such as soaking or double cooking. Sample potassium content was analyzed by triplicate using flamephotometry. The results showed significant reductions in potassium content in all culinary processes studied. The degree of loss varied depending on the type of vegetable and processing applied. Frozen products achieved greater reductions than the fresh ones, obtaining in some cases losses greater than 90%. In addition, it was observed how in many cases the single application of a normal cooking reached potassium reductions to acceptable levels for its inclusion in renal patient diet. The results shown in this study are very positive because they provide tools for professionals who deal with this kind of patients. They allow them to adapt more easily to the needs and preferences of their patients and increase dietary variety. Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  14. Whole-leaf wash improves chlorine efficacy for microbial reduction and prevents pathogen cross-contamination during fresh-cut lettuce processing.

    PubMed

    Nou, Xiangwu; Luo, Yaguang

    2010-06-01

    Currently, most fresh-cut processing facilities in the United States use chlorinated water or other sanitizer solutions for microbial reduction after lettuce is cut. Freshly cut lettuce releases significant amounts of organic matter that negatively impacts the effectiveness of chlorine or other sanitizers for microbial reduction. The objective of this study is to evaluate whether a sanitizer wash before cutting improves microbial reduction efficacy compared to a traditional postcutting sanitizer wash. Romaine lettuce leaves were quantitatively inoculated with E. coli O157:H7 strains and washed in chlorinated water before or after cutting, and E. coli O157:H7 cells that survived the washing process were enumerated to determine the effectiveness of microbial reduction for the 2 cutting and washing sequences. Whole-leaf washing in chlorinated water improved pathogen reduction by approximately 1 log unit over traditional cut-leaf sanitization. Similar improvement in the reduction of background microflora was also observed. Inoculated "Lollo Rossa" red lettuce leaves were mixed with noninoculated Green-Leaf lettuce leaves to evaluate pathogen cross-contamination during processing. High level (96.7% subsamples, average MPN 0.6 log CFU/g) of cross-contamination of noninoculated green leaves by inoculated red leaves was observed when mixed lettuce leaves were cut prior to washing in chlorinated water. In contrast, cross-contamination of noninoculated green leaves was significantly reduced (3.3% of subsamples, average MPN reduction and cross-contamination prevention.

  15. Modeling and Reduction With Applications to Semiconductor Processing

    DTIC Science & Technology

    1999-01-01

    smoothies ,” as they kept my energy level high without resorting to coffee (the beverage of choice, it seems, for graduate students). My advisor gave me all...with POC data, and balancing approach. . . . . . . . . . . . . . . . 312 xii LIST OF FIGURES 1.1 General state-space model reduction methodology ...reduction problem, then, is one of finding a systematic methodology within a given mathematical framework to produce an efficient or optimal trade-off of

  16. Effect of washing process on the magnetic properties of Nd-Fe-B nanoparticles prepared by reduction-diffusion method

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Ahn, J.; Kim, D.; Ren, W. J.; Liu, W.; Zhang, Z. D.; Choi, C. J.

    2017-10-01

    Nd-Fe-B nanoparticles with a particle size below 50 nm and excellent magnetic properties were obtained via a novel route which makes use of both spray drying and reduction-diffusion processes. Uniform Nd-Fe-B particles were formed by the optimization of Ca amount as a reducing agent and additional washing by milling in ethanol media. Especially, we implemented a two-step washing process which contributed to the excellent magnetic properties with high remanence and coercivity. After the removal of CaO by novel washing process, the maximum energy product (BH)max of the particles showed 22.1 MGOe. This value is superior to those reported in reduction-diffusion process. We used Henkel plot to assume the mechanism of magnetic interactions of the Nd-Fe-B nanoparticles.

  17. Brushing Your Spacecrafts Teeth: A Review of Biological Reduction Processes for Planetary Protection Missions

    NASA Technical Reports Server (NTRS)

    Pugel, D. E. (Betsy); Rummel, J. D.; Conley, Catharine

    2017-01-01

    Much like keeping your teeth clean, where you brush away biofilms that your dentist calls "plaque," there are various methods to clean spaceflight hardware of biological contamination, known as biological reduction processes. Different approaches clean your hardware's "teeth" in different ways and with different levels of effectiveness. We know that brushing at home with a simple toothbrush is convenient and has a different level of impact vs. getting your teeth cleaned at the dentist. In the same way, there are some approaches to biological reduction that may require simple tools or more complex implementation approaches (think about sonicating or just soaking your dentures, vs. brushing them). There are also some that are more effective for different degrees of cleanliness and still some that have materials compatibility concerns. In this article, we review known and NASA-certified approaches for biological reduction, pointing out materials compatibility concerns and areas where additional research is needed.

  18. Brushing Your Spacecrafts Teeth: A Review of Biological Reduction Processes for Planetary Protection Missions

    NASA Technical Reports Server (NTRS)

    Pugel, D.E. (Betsy); Rummel, J. D.; Conley, C. A.

    2017-01-01

    Much like keeping your teeth clean, where you brush away biofilms that your dentist calls plaque, there are various methods to clean spaceflight hardware of biological contamination, known as biological reduction processes. Different approaches clean your hardwares teeth in different ways and with different levels of effectiveness. We know that brushing at home with a simple toothbrush is convenient and has a different level of impact vs. getting your teeth cleaned at the dentist. In the same way, there are some approaches to biological reduction that may require simple tools or more complex implementation approaches (think about sonicating or just soaking your dentures, vs. brushing them). There are also some that are more effective for different degrees of cleanliness and still some that have materials compatibility concerns. In this article, we review known and NASA-certified approaches for biological reduction, pointing out materials compatibility concerns and areas where additional research is needed.

  19. Carbon Dioxide Reduction Post-Processing Sub-System Development

    NASA Technical Reports Server (NTRS)

    Abney, Morgan B.; Miller, Lee A.; Greenwood, Zachary; Barton, Katherine

    2012-01-01

    The state-of-the-art Carbon Dioxide (CO2) Reduction Assembly (CRA) on the International Space Station (ISS) facilitates the recovery of oxygen from metabolic CO2. The CRA utilizes the Sabatier process to produce water with methane as a byproduct. The methane is currently vented overboard as a waste product. Because the CRA relies on hydrogen for oxygen recovery, the loss of methane ultimately results in a loss of oxygen. For missions beyond low earth orbit, it will prove essential to maximize oxygen recovery. For this purpose, NASA is exploring an integrated post-processor system to recover hydrogen from CRA methane. The post-processor, called a Plasma Pyrolysis Assembly (PPA) partially pyrolyzes methane to recover hydrogen with acetylene as a byproduct. In-flight operation of post-processor will require a Methane Purification Assembly (MePA) and an Acetylene Separation Assembly (ASepA). Recent efforts have focused on the design, fabrication, and testing of these components. The results and conclusions of these efforts will be discussed as well as future plans.

  20. Effects of oxidation reduction potential in the bypass micro-aerobic sludge zone on sludge reduction for a modified oxic-settling-anaerobic process.

    PubMed

    Li, Kexun; Wang, Yi; Zhang, Zhongpin; Liu, Dongfang

    2014-01-01

    Batch experiments were conducted to determine the effect of oxidation reduction potential (ORP) on sludge reduction in a bypass micro-aerobic sludge reduction system. The system was composed of a modified oxic-settling-anaerobic process with a sludge holding tank in the sludge recycle loop. The ORPs in the micro-aerobic tanks were set at approximately +350, -90, -150, -200 and -250 mV, by varying the length of aeration time for the tanks. The results show that lower ORP result in greater sludge volume reduction, and the sludge production was reduced by 60% at the lowest ORP. In addition, low ORP caused extracellular polymer substances dissociation and slightly reduced sludge activity. Comparing the sludge backflow characteristics of the micro-aerobic tank's ORP controlled at -250 mV with that of +350 mV, the average soluble chemical oxygen (SCOD), TN and TP increased by 7, 0.4 and 2 times, median particle diameter decreased by 8.5 μm and the specific oxygen uptake rate (SOUR) decreased by 0.0043 milligram O2 per gram suspended solids per minute. For the effluent, SCOD and TN and TP fluctuated around 30, 8.7 and 0.66 mg/L, respectively. Therefore, the effective assignment of ORP in the micro-aerobic tank can remarkably reduce sludge volume and does not affect final effluent quality.

  1. ECO LOGIC INTERNATIONAL GAS-PHASE CHEMICAL REDUCTION PROCESS - THE THERMAL DESORPTION UNIT - APPLICATIONS ANALYSIS REPORT

    EPA Science Inventory

    ELI ECO Logic International, Inc.'s Thermal Desorption Unit (TDU) is specifically designed for use with Eco Logic's Gas Phase Chemical Reduction Process. The technology uses an externally heated bath of molten tin in a hydrogen atmosphere to desorb hazardous organic compounds fro...

  2. Effect of pH and pulsed electric field process parameters on the aflatoxin reduction in model system using response surface methodology: Effect of pH and PEF on Aflatoxin Reduction.

    PubMed

    Vijayalakshmi, Subramanian; Nadanasabhapathi, Shanmugam; Kumar, Ranganathan; Sunny Kumar, S

    2018-03-01

    The presence of aflatoxin, a carcinogenic and toxigenic secondary metabolite produced by Aspergillus species, in food matrix has been a major worldwide problem for years now. Food processing methods such as roasting, extrusion, etc. have been employed for effective destruction of aflatoxins, which are known for their thermo-stable nature. The high temperature treatment, adversely affects the nutritive and other quality attributes of the food, leading to the necessity of application of non-thermal processing techniques such as ultrasonication, gamma irradiation, high pressure processing, pulsed electric field (PEF), etc. The present study was focused on analysing the efficacy of the PEF process in the reduction of the toxin content, which was subsequently quantified using HPLC. The process parameters of different pH model system (potato dextrose agar) artificially spiked with aflatoxin mix standard was optimized using the response surface methodology. The optimization of PEF process effects on the responses aflatoxin B1 and total aflatoxin reduction (%) by pH (4-10), pulse width (10-26 µs) and output voltage (20-65%), fitted 2FI model and quadratic model respectively. The response surface plots obtained for the processes were of saddle point type, with the absence of minimum or maximum response at the centre point. The implemented numerical optimization showed that the predicted and actual values were similar, proving the adequacy of the fitted models and also proved the possible application of PEF in toxin reduction.

  3. Using normalisation process theory to understand barriers and facilitators to implementing mindfulness-based stress reduction for people with multiple sclerosis.

    PubMed

    Simpson, Robert; Simpson, Sharon; Wood, Karen; Mercer, Stewart W; Mair, Frances S

    2018-01-01

    Objectives To study barriers and facilitators to implementation of mindfulness-based stress reduction for people with multiple sclerosis. Methods Qualitative interviews were used to explore barriers and facilitators to implementation of mindfulness-based stress reduction, including 33 people with multiple sclerosis, 6 multiple sclerosis clinicians and 2 course instructors. Normalisation process theory provided the underpinning conceptual framework. Data were analysed deductively using normalisation process theory constructs (coherence, cognitive participation, collective action and reflexive monitoring). Results Key barriers included mismatched stakeholder expectations, lack of knowledge about mindfulness-based stress reduction, high levels of comorbidity and disability and skepticism about embedding mindfulness-based stress reduction in routine multiple sclerosis care. Facilitators to implementation included introducing a pre-course orientation session; adaptations to mindfulness-based stress reduction to accommodate comorbidity and disability and participants suggested smaller, shorter classes, shortened practices, exclusion of mindful-walking and more time with peers. Post-mindfulness-based stress reduction booster sessions may be required, and objective and subjective reports of benefit would increase clinician confidence in mindfulness-based stress reduction. Discussion Multiple sclerosis patients and clinicians know little about mindfulness-based stress reduction. Mismatched expectations are a barrier to participation, as is rigid application of mindfulness-based stress reduction in the context of disability. Course adaptations in response to patient needs would facilitate uptake and utilisation. Rendering access to mindfulness-based stress reduction rapid and flexible could facilitate implementation. Embedded outcome assessment is desirable.

  4. New understanding on separation of Mn and Fe from ferruginous manganese ores by the magnetic reduction roasting process

    NASA Astrophysics Data System (ADS)

    Liu, Bingbing; Zhang, Yuanbo; Wang, Juan; Wang, Jia; Su, Zijian; Li, Guanghui; Jiang, Tao

    2018-06-01

    Magnetic reduction roasting followed by magnetic separation process is reported as a simple route to realize separation of Mn and Fe from ferruginous manganese ores (Fe-Mn ores). However, the separation and recovery of Mn and Fe oxides are not very effective. This work clarified the underlying reason for the poor separation and also proposed some suggestions for the magnetic reduction process. In this work, the effect of temperature on the magnetic reduction roasting - magnetic separation of Fe-Mn ore was investigated firstly. Then the reduction behaviors of MnO2-Fe2O3 system and MnO2-Fe2O3-10 wt.%SiO2 system under 10 vol.% CO-90 vol.% CO2 at 600-1000 °C were investigated by XRD, XPS, SEM-EDS, VSM, DSC and thermodynamics analyses. Reduction and separation tests showed that higher reduction temperature was beneficial to the recovery of iron while it's not in favor of the recovery of manganese when the temperature was over 800 °C. The formation of composite oxide MnxFe3-xO4 with strong magnetism between the interface of the MnO2 and Fe2O3 particles leaded to the poor separation of iron and manganese. In addition, the formation mechanism of MnxFe3-xO4 from MnO2 and Fe2O3 as well as the interface reaction reduced under 10 vol.% CO was discussed in this study. Finally, some suggestions were recommended for the magnetic reduction roasting for utilizing the Fe-Mn ores effectively.

  5. User's guide to the UTIL-ODRC tape processing program. [for the Orbital Data Reduction Center

    NASA Technical Reports Server (NTRS)

    Juba, S. M. (Principal Investigator)

    1981-01-01

    The UTIL-ODRC computer compatible tape processing program, its input/output requirements, and its interface with the EXEC 8 operating system are described. It is a multipurpose orbital data reduction center (ODRC) tape processing program enabling the user to create either exact duplicate tapes and/or tapes in SINDA/HISTRY format. Input data elements for PRAMPT/FLOPLT and/or BATCH PLOT programs, a temperature summary, and a printed summary can also be produced.

  6. Greek "red mud" residue: a study of microwave reductive roasting followed by magnetic separation for a metallic iron recovery process.

    PubMed

    Samouhos, Michail; Taxiarchou, Maria; Tsakiridis, Petros E; Potiriadis, Konstantinos

    2013-06-15

    The present research work is focused on the development of an alternative microwave reductive roasting process of red mud using lignite (30.15 wt.%Cfix), followed by wet magnetic separation, in order to produce a raw material suitable for sponge or cast iron production. The reduction degree of iron was controlled by both the reductive agent content and the microwave heating time. The reduction followed the Fe₂O₃ → Fe₃O₄ → FeO → Fe sequence. The dielectric constants [real (ε') and imaginary (ε″) permittivities] of red mud-lignite mixture were determined at 2.45 GHz, in the temperature range of 25-1100 °C. The effect of parameters such as temperature, intensity of reducing conditions, intensity of magnetic field and dispersing agent addition rate on the result of both processes was investigated. The phase's transformations in reduction process with microwave heating were determined by X-ray diffraction analysis (XRD) in combination with thermogravimetric/differential thermal analysis (TGA/DTA). The microstructural and morphological characterization of the produced calcines was carried out by scanning electron microscopy (SEM). At the optimum conditions a magnetic concentrate with total iron concentration of 35.15 and 69.3 wt.% metallization degree was obtained. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Stages and Processes of Change Utilized by Female Sex Workers Participating in an Alcohol-Reduction Intervention in Mombasa, Kenya.

    PubMed

    Velloza, Jennifer; L'Engle, Kelly; Mwarogo, Peter; Chokwe, Jackie; Magaria, Loice; Sinkele, William; Kingola, Nzioki

    2015-01-01

    According to the transtheoretical model (TTM) behavior change occurs through a series of steps when an individual becomes aware of a behavior, prepares to change, and executes those changes using certain processes. This model has not yet been used to describe alcohol-reduction behavior change processes in resource-limited settings. This qualitative analysis aimed to describe and characterize the stages and processes of change employed by female sex workers in Mombasa, Kenya during the course of their participation in a 6-month alcohol reduction intervention. In 2011-2012, clinical interviews were conducted with 45 female sex workers. One interview was conducted each month during the intervention period, resulting in a total of six transcripts per participant. During each interview, the counselor noted the participant's stage of change and recent alcohol use. The clinical notes were analyzed via qualitative coding techniques and organized into matrices to classify alcohol reduction strategies discussed by participants. Participants discussed using the stage-specific processes of change described by the TTM to reduce their alcohol use and maintain the behavior change. Participants who were HIV-positive at the start of the intervention seemed to progress to the action/maintenance stage more quickly than HIV-negative participants. Results suggest that the TTM constructs may be relevant in understanding the alcohol reduction behavior change process of an at-risk population in a resource-limited setting. Future quantitative research should seek to validate the TTM's application internationally. Alcohol interventions should consider tailoring content to participants' stages of change and HIV-status for increased effectiveness.

  8. Reduction Behavior of Assmang and Comilog ore in the SiMn Process

    NASA Astrophysics Data System (ADS)

    Kim, Pyunghwa Peace; Holtan, Joakim; Tangstad, Merete

    The reduction behavior of raw materials from Assmang and Comilog based charges were experimentally investigated with CO gas up to 1600 °C. Quartz, HC FeMn slag or limestone were added to Assmang or Comilog according to the SiMn production charge, and mass loss results were obtained by using a TGA furnace. The results showed that particle size, type of manganese ore and mixture have close relationship to the reduction behavior of raw materials during MnO and SiO2 reduction. The influence of particle size to mass loss was apparent when Assmang or Comilog was mixed with only coke (FeMn) while it became insignificant when quartz and HC FeMn slag (SiMn) were added. This implied that quartz and HC FeMn slag had favored the incipient slag formation regardless of particle size. This explained the similar mass loss tendencies of SiMn charge samples between 1200-1500 °C, contrary to FeMn charge samples where different particle sizes showed significant difference in mass loss. Also, while FeMn charge samples showed progressive mass loss, SiMn charge samples showed diminutive mass loss until 1500 °C. However, rapid mass losses were observed with SiMn charge samples in this study above 1500 °C, and they have occurred at different temperatures. This implied rapid reduction of MnO and SiO2 and the type of ore and addition of HC FeMn slag have significant influence determining these temperatures. The temperatures observed for the rapid mass loss were approximately 1503 °C (Quartz and HC FeMn slag addition in Assmang), 1543 °C (Quartz addition in Assmang) and 1580-1587 °C (Quartz and limestone addition in Comilog), respectively. These temperatures also showed indications of possible SiMn production at process temperatures lower than 1550 °C.

  9. GREENER CHEMICAL PROCESS DESIGN ALTERNATIVES ARE REVEALED USING THE WASTE REDUCTION DECISION SUPPORT SYSTEM (WAR DSS)

    EPA Science Inventory

    The Waste Reduction Decision Support System (WAR DSS) is a Java-based software product providing comprehensive modeling of potential adverse environmental impacts (PEI) predicted to result from newly designed or redesigned chemical manufacturing processes. The purpose of this so...

  10. Monoclonal antibody disulfide reduction during manufacturing

    PubMed Central

    Hutterer, Katariina M.; Hong, Robert W.; Lull, Jonathon; Zhao, Xiaoyang; Wang, Tian; Pei, Rex; Le, M. Eleanor; Borisov, Oleg; Piper, Rob; Liu, Yaoqing Diana; Petty, Krista; Apostol, Izydor; Flynn, Gregory C.

    2013-01-01

    Manufacturing-induced disulfide reduction has recently been reported for monoclonal human immunoglobulin gamma (IgG) antibodies, a widely used modality in the biopharmaceutical industry. This effect has been tied to components of the intracellular thioredoxin reduction system that are released upon cell breakage. Here, we describe the effect of process parameters and intrinsic molecule properties on the extent of reduction. Material taken from cell cultures at the end of production displayed large variations in the extent of antibody reduction between different products, including no reduction, when subjected to the same reduction-promoting harvest conditions. Additionally, in a reconstituted model in which process variables could be isolated from product properties, we found that antibody reduction was dependent on the cell line (clone) and cell culture process. A bench-scale model using a thioredoxin/thioredoxin reductase regeneration system revealed that reduction susceptibility depended on not only antibody class but also light chain type; the model further demonstrates that the trend in reducibility was identical to DTT reduction sensitivity following the order IgG1λ > IgG1κ > IgG2λ > IgG2κ. Thus, both product attributes and process parameters contribute to the extent of antibody reduction during production. PMID:23751615

  11. Process integration for biological sulfate reduction in a carbon monoxide fed packed bed reactor.

    PubMed

    Kumar, Manoj; Sinharoy, Arindam; Pakshirajan, Kannan

    2018-08-01

    This study examined immobilized anaerobic biomass for sulfate reduction using carbon monoxide (CO) as the sole carbon source under batch and continuous fed conditions. The immobilized bacteria with beads made of 10% polyvinyl alcohol (PVA) showed best results in terms of sulfate reduction (84 ± 3.52%) and CO utilization (98 ± 1.67%). The effect of hydraulic retention time (HRT), sulfate loading rate and CO loading rate on sulfate and CO removal was investigated employing a 1L packed bed bioreactor containing the immobilized biomass. At 48, 24 and 12 h HRT, the sulfate removal was 94.42 ± 0.15%, 89.75 ± 0.47% and 61.08 ± 0.34%, respectively, along with a CO utilization of more than 90%. The analysis of variance (ANOVA) of the results obtained showed that only the initial CO concentration significantly affected the sulfate reduction process. The reactor effluent sulfate concentrations were 27.41 ± 0.44, 59.16 ± 1.08, 315.83 ± 7.33 mg/L for 250, 500 and 1000 mg/L of influent sulfate concentrations respectively, under the optimum operating conditions. The sulfate reduction rates matched well with low inlet sulfate loading rates, indicating stable performance of the bioreactor system. Overall, this study yielded very high sulfate reduction efficiency by the immobilized anaerobic biomass under high CO loading condition using the packed bed reactor system. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Performing a local reduction operation on a parallel computer

    DOEpatents

    Blocksome, Michael A; Faraj, Daniel A

    2013-06-04

    A parallel computer including compute nodes, each including two reduction processing cores, a network write processing core, and a network read processing core, each processing core assigned an input buffer. Copying, in interleaved chunks by the reduction processing cores, contents of the reduction processing cores' input buffers to an interleaved buffer in shared memory; copying, by one of the reduction processing cores, contents of the network write processing core's input buffer to shared memory; copying, by another of the reduction processing cores, contents of the network read processing core's input buffer to shared memory; and locally reducing in parallel by the reduction processing cores: the contents of the reduction processing core's input buffer; every other interleaved chunk of the interleaved buffer; the copied contents of the network write processing core's input buffer; and the copied contents of the network read processing core's input buffer.

  13. Performing a local reduction operation on a parallel computer

    DOEpatents

    Blocksome, Michael A.; Faraj, Daniel A.

    2012-12-11

    A parallel computer including compute nodes, each including two reduction processing cores, a network write processing core, and a network read processing core, each processing core assigned an input buffer. Copying, in interleaved chunks by the reduction processing cores, contents of the reduction processing cores' input buffers to an interleaved buffer in shared memory; copying, by one of the reduction processing cores, contents of the network write processing core's input buffer to shared memory; copying, by another of the reduction processing cores, contents of the network read processing core's input buffer to shared memory; and locally reducing in parallel by the reduction processing cores: the contents of the reduction processing core's input buffer; every other interleaved chunk of the interleaved buffer; the copied contents of the network write processing core's input buffer; and the copied contents of the network read processing core's input buffer.

  14. Identifying the influential aquifer heterogeneity factor on nitrate reduction processes by numerical simulation

    NASA Astrophysics Data System (ADS)

    Jang, E.; He, W.; Savoy, H.; Dietrich, P.; Kolditz, O.; Rubin, Y.; Schüth, C.; Kalbacher, T.

    2017-01-01

    Nitrate reduction reactions in groundwater systems are strongly influenced by various aquifer heterogeneity factors that affect the transport of chemical species, spatial distribution of redox reactive substances and, as a result, the overall nitrate reduction efficiency. In this study, we investigated the influence of physical and chemical aquifer heterogeneity, with a focus on nitrate transport and redox transformation processes. A numerical modeling study for simulating coupled hydrological-geochemical aquifer heterogeneity was conducted in order to improve our understanding of the influence of the aquifer heterogeneity on the nitrate reduction reactions and to identify the most influential aquifer heterogeneity factors throughout the simulation. Results show that the most influential aquifer heterogeneity factors could change over time. With abundant presence of electron donors in the high permeable zones (initial stage), physical aquifer heterogeneity significantly influences the nitrate reduction since it enables the preferential transport of nitrate to these zones and enhances mixing of reactive partners. Chemical aquifer heterogeneity plays a comparatively minor role. Increasing the spatial variability of the hydraulic conductivity also increases the nitrate removal efficiency of the system. However, ignoring chemical aquifer heterogeneity can lead to an underestimation of nitrate removals in long-term behavior. With the increase of the spatial variability of the electron donor, i.e. chemical heterogeneity, the number of the ;hot spots; i.e. zones with comparably higher reactivity, should also increase. Hence, nitrate removal efficiencies will also be spatially variable but overall removal efficiency will be sustained if longer time scales are considered and nitrate fronts reach these high reactivity zones.

  15. Comparative reduction of Giardia cysts, F+ coliphages, sulphite reducing clostridia and fecal coliforms by wastewater treatment processes.

    PubMed

    Nasser, Abidelfatah M; Benisti, Neta-Lee; Ofer, Naomi; Hovers, Sivan; Nitzan, Yeshayahu

    2017-01-28

    Advanced wastewater treatment processes are applied to prevent the environmental dissemination of pathogenic microorganisms. Giardia lamblia causes a severe disease called giardiasis, and is highly prevalent in untreated wastewater worldwide. Monitoring the microbial quality of wastewater effluents is usually based on testing for the levels of indicator microorganisms in the effluents. This study was conducted to compare the suitability of fecal coliforms, F+ coliphages and sulfide reducing clostridia (SRC) as indicators for the reduction of Giardia cysts in two full-scale wastewater treatment plants. The treatment process consists of activated sludge, coagulation, high rate filtration and either chlorine or UV disinfection. The results of the study demonstrated that Giardia cysts are highly prevalent in raw wastewater at an average concentration of 3600 cysts/L. Fecal coliforms, F+ coliphages and SRC were also detected at high concentrations in raw wastewater. Giardia cysts were efficiently removed (3.6 log 10 ) by the treatment train. The greatest reduction was observed for fecal coliforms (9.6 log 10 ) whereas the least reduction was observed for F+ coliphages (2.1 log 10 ) following chlorine disinfection. Similar reduction was observed for SRC by filtration and disinfection by either UV (3.6 log 10 ) or chlorine (3.3 log 10 ). Since F+ coliphage and SRC were found to be more resistant than fecal coliforms for the tertiary treatment processes, they may prove to be more suitable as indicators for Giardia. The results of this study demonstrated that advanced wastewater treatment may prove efficient for the removal of Giardia cysts and may prevent its transmission when treated effluents are applied for crop irrigation or streams restoration.

  16. A novel aerobic sulfate reduction process in landfill mineralized refuse.

    PubMed

    Liu, Weijia; Long, Yuyang; Fang, Yuan; Ying, Luyao; Shen, Dongsheng

    2018-05-08

    It is thought that mineralized refuse could be excavated from almost-full landfill sites to provide space for the increasing burden of municipal solid waste. When excavating, however, the H 2 S emissions from the mineralized waste need to be considered carefully. In an attempt to understand how H 2 S emissions might change during this excavation process, we carried out a series of tests, including exposing anaerobic mineralized refuse to oxygen, isolating and determining possible functional bacteria, and characterizing the electron donors and/or acceptors. The results showed that H 2 S would be released when landfill mineralized refuse was exposed to oxygen (O 2 ), and could reach concentrations of 6 mg m -3 , which was 3 times the concentrations of H 2 S released from anaerobic mineralized refuse. Sulfur-metabolized microorganisms accounted for only 0.5% of the microbial functional bacteria (MFB) derived from the mineralized refuse when exposed to O 2 for 60 days, and SRB were not present. The MFB maintained H 2 S production by aerobic sulfate reduction using SO 4 2- and S 2 O 3 2- as electron acceptors, and sulfate-reducing rates of 16% and 55%, respectively, were achieved. Lactate and S 2 O 3 2- were the preferred electron donor and acceptor, respectively. By enhancing the carbon source and electron transfer, MFB may undergo strong aerobic sulfate reduction even at low abundances of sulfur-metabolized microorganisms. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. A MIXED CHEMICAL REDUCTANT FOR TREATING HEXAVALENT CHROMIUM IN A CHROMITE ORE PROCESSING SOLID WASTE

    EPA Science Inventory

    We evaluated a method for delivering ferrous iron into the subsurface to enhance chemical reduction of Cr(VI) in a chromite ore processing solid waste (COPSW). The COPSW is characterized by high pH (8.5 -11.5), high Cr(VI) concentrations in the solid phase (up to 550 mg kg-1) and...

  18. Effects of process variables and kinetics on the degradation of 2,4-dichlorophenol using advanced reduction processes (ARP).

    PubMed

    Yu, Xingyue; Cabooter, Deirdre; Dewil, Raf

    2018-05-24

    This study aims at investigating the efficiency and kinetics of 2,4-DCP degradation via advanced reduction processes (ARP). Using UV light as activation method, the highest degradation efficiency of 2,4-DCP was obtained when using sulphite as a reducing agent. The highest degradation efficiency was observed under alkaline conditions (pH = 10.0), for high sulphite dosage and UV intensity, and low 2,4-DCP concentration. For all process conditions, first-order reaction rate kinetics were applicable. A quadratic polynomial equation fitted by a Box-Behnken Design was used as a statistical model and proved to be precise and reliable in describing the significance of the different process variables. The analysis of variance demonstrated that the experimental results were in good agreement with the predicted model (R 2  = 0.9343), and solution pH, sulphite dose and UV intensity were found to be key process variables in the sulphite/UV ARP. Consequently, the present study provides a promising approach for the efficient degradation of 2,4-DCP with fast degradation kinetics. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Material and system for catalytic reduction of nitrogen oxide in an exhaust stream of a combustion process

    DOEpatents

    Gardner, Timothy J.; Lott, Stephen E.; Lockwood, Steven J.; McLaughlin, Linda I.

    1998-01-01

    A catalytic material of activated hydrous metal oxide doped with platinum, palladium, or a combination of these, and optionally containing an alkali or alkaline earth metal, that is effective for NO.sub.X reduction in an oxidizing exhaust stream from a combustion process is disclosed. A device for reduction of nitrogen oxides in an exhaust stream, particularly an automotive exhaust stream, the device having a substrate coated with the activated noble-metal doped hydrous metal oxide of the invention is also provided.

  20. Reduction of carbon contamination during the melting process of Czochralski silicon crystal growth

    NASA Astrophysics Data System (ADS)

    Liu, Xin; Gao, Bing; Nakano, Satoshi; Kakimoto, Koichi

    2017-09-01

    Generation, incorporation, and accumulation of carbon (C) were investigated by transient global simulations of heat and mass transport during the melting process of Czochralski silicon (CZ-Si) crystal growth. Contact reaction between the quartz crucible and graphite susceptor was introduced as an extra origin of C contamination. The contribution of the contact reaction on C accumulation is affected by the back diffusion of C monoxide (CO) from the gap between the gas-guide and the crucible. The effect of the gas-guide coating on C reduction was elucidated by taking the reaction between the silicon carbide (SiC) coating and gaseous Si monoxide (SiO) into account. Application of the SiC coating on the gas-guide could effectively reduce the C contamination because of its higher thermochemical stability relative to that of graphite. Gas flow control on the back diffusion of the generated CO was examined by the parametric study of argon gas flow rate. Generation and back diffusion of CO were both effectively suppressed by the increase in the gas flow rate because of the high Péclet number of species transport. Strategies for C content reduction were discussed by analyzing the mechanisms of C accumulation process. According to the elucidated mechanisms of C accumulation, the final C content depends on the growth duration and contamination flux at the gas/melt interface.

  1. [Analysis of carbon balance and study on mechanism in anoxic-oxic-settling-anaerobic sludge reduction process].

    PubMed

    Zhai, Xiao-Min; Gao, Xu; Zhang, Man-Man; Jia, Li; Guo, Jin-Song

    2012-07-01

    In order to deeply explore the mechanism of sludge reduction in OSA system, carbon balance was performed in an anoxic-oxic-settling-anaerobic (A + OSA) system and a reference AO system to investigate effects of inserting a sludge holding tank in sludge cycle line on the sludge reduction process. Meanwhile, carbon mass change in each reaction unit was identified in terms of solid, liquid and gas phases. The causes of excess sludge reduction in A + OSA system were deduced. The carbon balance results show that when the hydraulic retention time in the sludge holding tank is 7.14 h, carbon percent in solid phase of the sludge reduction system is nearly 50% higher than that of the reference system, supporting the consequence that sludge reduction rate of 49.98% had been achieved. The insertion of a sludge holding tank in the sludge return circuit can be effective in sludge reduction. Carbon changes in each unit reveal that the amount of carbon consumed for biosynthesis in the anoxic and oxic tanks (main reaction zone) of the sludge reduction system is higher than in that of the reference system. Sludge decay is observed in the sludge holding tank. Furthermore, CH4 released from the sludge holding tank is significantly higher than that from the main reaction zone. The DGGE profiles show that there are hydrolytic-fermentative bacteria in the sludge holding tank related to sludge decay. The excess sludge reduction in the A + OSA system could be a result of the combination of sludge decay in the sludge holding tank and sludge compensatory growth in the main reaction cell.

  2. In-camera video-stream processing for bandwidth reduction in web inspection

    NASA Astrophysics Data System (ADS)

    Jullien, Graham A.; Li, QiuPing; Hajimowlana, S. Hossain; Morvay, J.; Conflitti, D.; Roberts, James W.; Doody, Brian C.

    1996-02-01

    Automated machine vision systems are now widely used for industrial inspection tasks where video-stream data information is taken in by the camera and then sent out to the inspection system for future processing. In this paper we describe a prototype system for on-line programming of arbitrary real-time video data stream bandwidth reduction algorithms; the output of the camera only contains information that has to be further processed by a host computer. The processing system is built into a DALSA CCD camera and uses a microcontroller interface to download bit-stream data to a XILINXTM FPGA. The FPGA is directly connected to the video data-stream and outputs data to a low bandwidth output bus. The camera communicates to a host computer via an RS-232 link to the microcontroller. Static memory is used to both generate a FIFO interface for buffering defect burst data, and for off-line examination of defect detection data. In addition to providing arbitrary FPGA architectures, the internal program of the microcontroller can also be changed via the host computer and a ROM monitor. This paper describes a prototype system board, mounted inside a DALSA camera, and discusses some of the algorithms currently being implemented for web inspection applications.

  3. Automated and Scalable Data Reduction in the textsc{Sofia} Data Processing System

    NASA Astrophysics Data System (ADS)

    Krzaczek, R.; Shuping, R.; Charcos-Llorens, M.; Alles, R.; Vacca, W.

    2015-09-01

    In order to provide suitable data products to general investigators and other end users in a timely manner, the Stratospheric Observatory for Infrared Astronomy SOFIA) has developed a framework supporting the automated execution of data processing pipelines for the various instruments, called the Data Processing System (DPS), see Shuping et al. (2014) for overview). The primary requirement is to process all data collected from a flight within eight hours, allowing data quality assessments and inspections to be made the following day. The raw data collected during a flight requires processing by a number of different software packages and tools unique to each combination of instrument and mode of operation, much of it developed in-house, in order to create data products for use by investigators and other end-users. The requirement to deliver these data products in a consistent, predictable, and performant manner presents a significant challenge for the observatory. Herein we present aspects of the DPS that help to achieve these goals. We discuss how it supports data reduction software written in a variety of languages and environments, its support for new versions and live upgrades to that software and other necessary resources (e.g., calibrations), its accommodation of sudden processing loads through the addition (and eventual removal) of computing resources, and close with an observation of the performance achieved in the first two observing cycles of SOFIA.

  4. The demonstration of a novel sulfur cycle-based wastewater treatment process: sulfate reduction, autotrophic denitrification, and nitrification integrated (SANI®) biological nitrogen removal process.

    PubMed

    Lu, Hui; Wu, Di; Jiang, Feng; Ekama, George A; van Loosdrecht, Mark C M; Chen, Guang-Hao

    2012-11-01

    Saline water supply has been successfully practiced for toilet flushing in Hong Kong since 1950s, which saves 22% of freshwater in Hong Kong. In order to extend the benefits of saline water supply into saline sewage management, we have recently developed a novel biological organics and nitrogen removal process: the Sulfate reduction, Autotrophic denitrification, and Nitrification Integrated (SANI®) process. The key features of this novel process include elimination of oxygen demand in organic matter removal and production of minimal sludge. Following the success of a 500-day lab-scale trial, this study reports a pilot scale evaluation of this novel process treating 10 m(3) /day of 6-mm screened saline sewage in Hong Kong. The SANI® pilot plant consisted of a sulfate reduction up-flow sludge bed (SRUSB) reactor, an anoxic bioreactor for autotrophic denitrification and an aerobic bioreactor for nitrification. The plant was operated at a steady state for 225 days, during which the average removal efficiencies of both chemical oxygen demand (COD) and total suspended solids (TSS) at 87% and no excess sludge was purposefully withdrawn. Furthermore, a tracer test revealed 5% short circuit flow and a 34.6% dead zone in the SRUSB, indicating a good possibility to further optimize the treatment capacity of the process for full-scale application. Compared with conventional biological nitrogen removal processes, the SANI® process reduces 90% of waste sludge, which saves 35% of the energy and reduces 36% of fossil CO(2) emission. The SANI® process not only eliminates the major odor sources originating from primary treatment and subsequent sludge treatment and disposal during secondary saline sewage treatment, but also promotes saline water supply as an economic and sustainable solution for water scarcity and sewage treatment in water-scarce coastal areas. Copyright © 2012 Wiley Periodicals, Inc.

  5. Processing, structure, and characterizaton of nickel-alumina composites obtained by the partial reduction of zirconia-doped nickel-aluminum oxide and application to the tempering of ceramics

    NASA Astrophysics Data System (ADS)

    Barbieri, Thomas John

    1999-11-01

    Partial reduction of the spinel compound NiAl2O4 results in a two phase composite mixture of Ni + Al2O3. The reduction reaction has a volume decrease associated with it, which theoretically could generate large residual stresses, which have the potential to "temper" a ceramic, i.e. to place the surface of a ceramic component into a state of residual compression. As the first step towards tempering a ceramic, it is necessary to demonstrate that appreciable stresses can be generated by this volume change, since they may be relieved by either cracking or diffusional relaxation processes at the high temperature of the reduction reaction. It was necessary to determine the best processing methods to use for producing the tempered specimens. Results are presented from a systematic study on the effect of the variation of processing parameters on the reduction behavior of NiAl2O4 doped with ZrO2. Specimen characteristics of interest were time required for reduction, microstructural development, volume contraction achieved and porosity generated during reduction, and the ability to survive the reduction process without fracturing. These results were applied to the tempering process. A simple specimen geometry was used for tempering which involved an Al 2O3 cylinder bonded to an outer NiAl2O4 ring. Finite element calculations were performed to predict the residual stresses generated by the volume contraction of the ring and the coefficient of thermal expansion, (CTE) mismatch between the Al2O3 core and the reduced composite ring. Stress measurements performed on the Al2 O3 core of each specimen using the "d vs. Sin 2Psi" method of X-ray diffraction indicate that only the CTE-induced stresses remain in the specimens after completion of the tempering process. Microstructural analysis of the tempered specimens was performed to determine if residual stresses were developed during reduction, and what processes occurred to relieve these stresses. The results indicate that stresses

  6. Nitric-glycolic flowsheet reduction/oxidation (redox) model for the defense waste processing facility (DWPF)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jantzen, C. M.; Williams, M. S.; Edwards, T. B.

    Control of the REDuction/OXidation (REDOX) state of glasses containing high concentrations of transition metals, such as High Level Waste (HLW) glasses, is critical in order to eliminate processing difficulties caused by overly reduced or overly oxidized melts. Operation of a HLW melter at Fe +2/ΣFe ratios of between 0.09 and 0.33, retains radionuclides in the melt and thus the final glass. Specifically, long-lived radioactive 99Tc species are less volatile in the reduced Tc 4+ state as TcO 2 than as NaTcO 4 or Tc 2O 7, and ruthenium radionuclides in the reduced Ru 4+ state are insoluble RuO 2 inmore » the melt which are not as volatile as NaRuO 4 where the Ru is in the +7 oxidation state. Similarly, hazardous volatile Cr 6+ occurs in oxidized melt pools as Na 2CrO 4 or Na 2Cr 2O 7, while the Cr +3 state is less volatile and remains in the melt as NaCrO 2 or precipitates as chrome rich spinels. The melter REDOX control balances the oxidants and reductants from the feed and from processing additives such as antifoam.« less

  7. Modeling of a CeO2 thermochemistry reduction process for hydrogen production by solar concentrated energy

    NASA Astrophysics Data System (ADS)

    Valle-Hernández, Julio; Romero-Paredes, Hernando; Arancibia-Bulnes, Camilo A.; Villafan-Vidales, Heidi I.; Espinosa-Paredes, Gilberto

    2016-05-01

    In this paper the simulation of the thermal reduction for hydrogen production through the decomposition of cerium oxide is presented. The thermochemical cycle for hydrogen production consists of the endothermic reduction of CeO2 at high temperature, where concentrated solar energy is used as a source of heat; and of the subsequent steam hydrolysis of the resulting cerium oxide to produce hydrogen. For the thermochemical process, a solar reactor prototype is proposed; consisting of a cubic receptacle made of graphite fiber thermally insulated. Inside the reactor a pyramidal arrangement with nine tungsten pipes is housed. The pyramidal arrangement is made respect to the focal point where the reflected energy is concentrated. The solar energy is concentrated through the solar furnace of high radiative flux. The endothermic step is the reduction of the cerium oxide to lower-valence cerium oxide, at very high temperature. The exothermic step is the hydrolysis of the cerium oxide (III) to form H2 and the corresponding initial cerium oxide made at lower temperature inside the solar reactor. For the modeling, three sections of the pipe where the reaction occurs were considered; the carrier gas inlet, the porous medium and the reaction products outlet. The mathematical model describes the fluid mechanics; mass and energy transfer occurring therein inside the tungsten pipe. Thermochemical process model was simulated in CFD. The results show a temperature distribution in the solar reaction pipe and allow obtaining the fluid dynamics and the heat transfer within the pipe. This work is part of the project "Solar Fuels and Industrial Processes" from the Mexican Center for Innovation in Solar Energy (CEMIE-Sol).

  8. Recharge processes drive sulfate reduction in an alluvial aquifer contaminated with landfill leachate

    USGS Publications Warehouse

    Scholl, M.A.; Cozzarelli, I.M.; Christenson, S.C.

    2006-01-01

    present in the root zone, and SO42- reduction may be coupled to methane oxidation. The results show that sulfur (and possibly nitrogen) redox processes within the top 2??m of the aquifer are directly related to recharge timing and seasonal water level changes in the aquifer. The results suggest that SO42- reduction associated with the infiltration of recharge may be a significant factor affecting natural attenuation of contaminants in alluvial aquifers. ?? 2006 Elsevier B.V. All rights reserved.

  9. Microfinance institutions and a coastal community's disaster risk reduction, response, and recovery process: a case study of Hatiya, Bangladesh.

    PubMed

    Parvin, Gulsan Ara; Shaw, Rajib

    2013-01-01

    Several researchers have examined the role of microfinance institutions (MFIs) in poverty alleviation, but the part that they play in disaster risk reduction remains unaddressed. Through an empirical study of Hatiya Island, one of the most vulnerable coastal communities of Bangladesh, this research evaluates perceptions of MFI support for the disaster risk reduction, response, and recovery process. The findings reveal no change in relation to risk reduction and income and occupation aspects for more than one-half of the clients of MFIs. In addition, only 26 per cent of them have witnessed less damage as a result of being members of MFIs. One can argue, though, that the longer the membership time period the better the disaster preparedness, response, and recovery process. The outcomes of this study could help to guide the current efforts of MFIs to enhance the ability of coastal communities to prepare for and to recover from disasters efficiently and effectively. © 2013 The Author(s). Journal compilation © Overseas Development Institute, 2013.

  10. IMPACTS OF ANTIFOAM ADDITIONS AND ARGON BUBBLING ON DEFENSE WASTE PROCESSING FACILITY REDUCTION/OXIDATION

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jantzen, C.; Johnson, F.

    2012-06-05

    During melting of HLW glass, the REDOX of the melt pool cannot be measured. Therefore, the Fe{sup +2}/{Sigma}Fe ratio in the glass poured from the melter must be related to melter feed organic and oxidant concentrations to ensure production of a high quality glass without impacting production rate (e.g., foaming) or melter life (e.g., metal formation and accumulation). A production facility such as the Defense Waste Processing Facility (DWPF) cannot wait until the melt or waste glass has been made to assess its acceptability, since by then no further changes to the glass composition and acceptability are possible. therefore, themore » acceptability decision is made on the upstream process, rather than on the downstream melt or glass product. That is, it is based on 'feed foward' statistical process control (SPC) rather than statistical quality control (SQC). In SPC, the feed composition to the melter is controlled prior to vitrification. Use of the DWPF REDOX model has controlled the balanjce of feed reductants and oxidants in the Sludge Receipt and Adjustment Tank (SRAT). Once the alkali/alkaline earth salts (both reduced and oxidized) are formed during reflux in the SRAT, the REDOX can only change if (1) additional reductants or oxidants are added to the SRAT, the Slurry Mix Evaporator (SME), or the Melter Feed Tank (MFT) or (2) if the melt pool is bubble dwith an oxidizing gas or sparging gas that imposes a different REDOX target than the chemical balance set during reflux in the SRAT.« less

  11. 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

  12. Reduction of N2 by supported tungsten clusters gives a model of the process by nitrogenase

    PubMed Central

    Murakami, Junichi; Yamaguchi, Wataru

    2012-01-01

    Metalloenzymes catalyze difficult chemical reactions under mild conditions. Mimicking their functions is a challenging task and it has been investigated using homogeneous systems containing metal complexes. The nitrogenase that converts N2 to NH3 under mild conditions is one of such enzymes. Efforts to realize the biological function have continued for more than four decades, which has resulted in several reports of reduction of N2, ligated to metal complexes in solutions, to NH3 by protonation under mild conditions. Here, we show that seemingly distinct supported small tungsten clusters in a dry environment reduce N2 under mild conditions like the nitrogenase. N2 is reduced to NH3 via N2H4 by addition of neutral H atoms, which agrees with the mechanism recently proposed for the N2 reduction on the active site of nitrogenase. The process on the supported clusters gives a model of the biological N2 reduction. PMID:22586517

  13. SITE PROGRAM DEMONSTRATION ECO LOGIC INTERNATIONAL GAS-PHASE CHEMICAL REDUCTION PROCESS, BAY CITY, MICHIGAN TECHNOLOGY EVALUATION REPORT

    EPA Science Inventory

    The SITE Program funded a field demonstration to evaluate the Eco Logic Gas-Phase Chemical Reduction Process developed by ELI Eco Logic International Inc. (ELI), Ontario, Canada. The Demonstration took place at the Middleground Landfill in Bay City, Michigan using landfill wa...

  14. Effect of process variables on the sulfate reduction process in bioreactors treating metal-containing wastewaters: factorial design and response surface analyses.

    PubMed

    Villa-Gomez, D K; Pakshirajan, K; Maestro, R; Mushi, S; Lens, P N L

    2015-07-01

    The individual and combined effect of the pH, chemical oxygen demand (COD) and SO4 (2-) concentration, metal to sulfide (M/S(2-)) ratio and hydraulic retention time (HRT) on the biological sulfate reduction (SR) process was evaluated in an inverse fluidized bed reactor by factorial design analysis (FDA) and response surface analysis (RSA). The regression-based model of the FDA described the experimental results well and revealed that the most significant variable affecting the process was the pH. The combined effect of the pH and HRT was barely observable, while the pH and COD concentration positive effect (up to 7 and 3 gCOD/L, respectively) enhanced the SR process. Contrary, the individual COD concentration effect only enhanced the COD removal efficiency, suggesting changes in the microbial pathway. The RSA showed that the M/S(2-) ratio determined whether the inhibition mechanism to the SR process was due to the presence of free metals or precipitated metal sulfides.

  15. Assessment of the GHG Reduction Potential from Energy Crops Using a Combined LCA and Biogeochemical Process Models: A Review

    PubMed Central

    Jiang, Dong; Hao, Mengmeng; Wang, Qiao; Huang, Yaohuan; Fu, Xinyu

    2014-01-01

    The main purpose for developing biofuel is to reduce GHG (greenhouse gas) emissions, but the comprehensive environmental impact of such fuels is not clear. Life cycle analysis (LCA), as a complete comprehensive analysis method, has been widely used in bioenergy assessment studies. Great efforts have been directed toward establishing an efficient method for comprehensively estimating the greenhouse gas (GHG) emission reduction potential from the large-scale cultivation of energy plants by combining LCA with ecosystem/biogeochemical process models. LCA presents a general framework for evaluating the energy consumption and GHG emission from energy crop planting, yield acquisition, production, product use, and postprocessing. Meanwhile, ecosystem/biogeochemical process models are adopted to simulate the fluxes and storage of energy, water, carbon, and nitrogen in the soil-plant (energy crops) soil continuum. Although clear progress has been made in recent years, some problems still exist in current studies and should be addressed. This paper reviews the state-of-the-art method for estimating GHG emission reduction through developing energy crops and introduces in detail a new approach for assessing GHG emission reduction by combining LCA with biogeochemical process models. The main achievements of this study along with the problems in current studies are described and discussed. PMID:25045736

  16. Investigation of Mercury Reduction in Gold Stripping Process at Elevated Temperature

    NASA Astrophysics Data System (ADS)

    Pramudya, Irawan

    Mercury is present in many gold ores. By processing these ores, there is a potential of emitting mercury to the environment. Carbon regeneration kiln stacks have been observed as one of the primary source of mercury emission into the atmosphere. Before it is recycled back into the carbon in leach (CIL) or carbon in columns (CIC), carbon used in the gold extraction process needs to be reactivated thermally. Emission of mercury can be minimized by keeping the mercury left in the carbon low before it goes to the carbon regeneration kiln stacks. The objective of this study is establishing the optimum elution conditions of mercury cyanide from loaded carbon (which includes the eluent, concentration, temperature and elution time) with respect to gold stripping. Several methods such as acid washing (UNR-100, HCl or ethanol/UNR-100) were investigated prior to the stripping process. Furthermore, conventional pressurized Zadra and modified Zadra were also studied with regards to mercury concentration in the solution and vapor state as well as maximizing the gold stripping from industrial loaded carbon. 7% UNR-100 acid washing of loaded carbon at 80°C was able to wash out approximately 90% of mercury while maintaining the gold adsorption on the carbon (selective washing). The addition of alcohol in the UNR-100 acid washing solution was able to enhance mercury washing from 90% to 97%. Furthermore, mercury stripping using conventional pressurized (cyanide-alkaline) Zadra was best performed at 80°C (minimal amount of mercury reduced and volatilized) whereas using the same process only 40% of gold was stripped, which makes this process not viable. When alcohol was added to the stripping solution, at 80°C, 95% of gold was detected in the solution while keeping the reduction and volatilization of mercury low. The outcome of this study provides a better understanding of mercury behavior during the acid washing and stripping processes so that the risk of mercury exposure and

  17. Combined Acquisition/Processing For Data Reduction

    NASA Astrophysics Data System (ADS)

    Kruger, Robert A.

    1982-01-01

    Digital image processing systems necessarily consist of three components: acquisition, storage/retrieval and processing. The acquisition component requires the greatest data handling rates. By coupling together the acquisition witn some online hardwired processing, data rates and capacities for short term storage can be reduced. Furthermore, long term storage requirements can be reduced further by appropriate processing and editing of image data contained in short term memory. The net result could be reduced performance requirements for mass storage, processing and communication systems. Reduced amounts of data also snouid speed later data analysis and diagnostic decision making.

  18. Sequential reductive and oxidative biodegradation of chloroethenes stimulated in a coupled bioelectro-process.

    PubMed

    Lohner, Svenja T; Becker, Dirk; Mangold, Klaus-Michael; Tiehm, Andreas

    2011-08-01

    This article for the first time demonstrates successful application of electrochemical processes to stimulate sequential reductive/oxidative microbial degradation of perchloroethene (PCE) in mineral medium and in contaminated groundwater. In a flow-through column system, hydrogen generation at the cathode supported reductive dechlorination of PCE to cis-dichloroethene (cDCE), vinyl chloride (VC), and ethene (ETH). Electrolytically generated oxygen at the anode allowed subsequent oxidative degradation of the lower chlorinated metabolites. Aerobic cometabolic degradation of cDCE proved to be the bottleneck for complete metabolite elimination. Total removal of chloroethenes was demonstrated for a PCE load of approximately 1.5 μmol/d. In mineral medium, long-term operation with stainless steel electrodes was demonstrated for more than 300 days. In contaminated groundwater, corrosion of the stainless steel anode occurred, whereas DSA (dimensionally stable anodes) proved to be stable. Precipitation of calcareous deposits was observed at the cathode, resulting in a higher voltage demand and reduced dechlorination activity. With DSA and groundwater from a contaminated site, complete degradation of chloroethenes in groundwater was obtained for two months thus demonstrating the feasibility of the sequential bioelectro-approach for field application.

  19. Oxidation-reduction catalyst and its process of use

    NASA Technical Reports Server (NTRS)

    Schryer, Jacqueline L. (Inventor); Oglesby, Donald M. (Inventor); Jordan, Jeffrey D. (Inventor); Watkins, Anthony Neal (Inventor)

    2008-01-01

    This invention relates generally to a ruthenium stabilized oxidation-reduction catalyst useful for oxidizing carbon monoxide, and volatile organic compounds, and reducing nitrogen oxide species in oxidizing environments, substantially without the formation of toxic and volatile ruthenium oxide species upon said oxidizing environment being at high temperatures.

  20. Selective catalytic reduction system and process for treating NOx emissions using a palladium and rhodium or ruthenium catalyst

    DOEpatents

    Sobolevskiy, Anatoly [Orlando, FL; Rossin, Joseph A [Columbus, OH; Knapke, Michael J [Columbus, OH

    2011-07-12

    A process for the catalytic reduction of nitrogen oxides (NOx) in a gas stream (29) in the presence of H.sub.2 is provided. The process comprises contacting the gas stream with a catalyst system (38) comprising zirconia-silica washcoat particles (41), a pre-sulfated zirconia binder (44), and a catalyst combination (40) comprising palladium and at least one of rhodium, ruthenium, or a mixture of ruthenium and rhodium.

  1. Revising the role of pH and thermal treatments in aflatoxin content reduction during the tortilla and deep frying processes.

    PubMed

    Torres, P; Guzmán-Ortiz, M; Ramírez-Wong, B

    2001-06-01

    Naturally aflatoxin-contaminated corn (Zea mays L.) was made into tortillas, tortilla chips, and corn chips by the traditional and commercial alkaline cooking processes. The traditional nixtamalization (alkaline-cooking) process involved cooking and steeping the corn, whereas the commercial nixtamalization process only steeps the corn in a hot alkaline solution (initially boiling). A pilot plant that includes the cooker, stone grinder, celorio cutter, and oven was used for the experiments. The traditional process eliminated 51.7, 84.5, and 78.8% of the aflatoxins content in tortilla, tortilla chips, and corn chips, respectively. The commercial process was less effective: it removed 29.5, 71.2, and 71.2 of the aflatoxin in the same products. Intermediate and final products did not reach a high enough pH to allow permanent aflatoxin reduction during thermal processing. The cooking or steeping liquor (nejayote) is the only component of the system with a sufficiently high pH (10.2-10.7) to allow modification and detoxification of aflatoxins present in the corn grain. The importance of removal of tip, pericarp, and germ during nixtamalization for aflatoxin reduction in tortilla is evident.

  2. Characterization of nickel laterite reduction from Pomalaa, Sulawesi Tenggara

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rhamdani, Ahmad Rizky; Petrus, Himawan T. B. M., E-mail: bayu.petrus@ugm.ac.id; Fahrurrozi, Moh.

    2015-12-29

    The effect of using different reductors in the reduction process of nickel laterite was investigated. In this work, the author conducted the reduction of nickel laterite ores by anthracite coal, lamtoro charcoal, and carbon raiser, in air and CO{sub 2} atmosphere, within the temperature ranged from 800°C and 1000°C. The results indicate that at higher temperatures, the reduction reactions proceed more complete. According to the X-ray powder diffraction (XRD) analysis, the type of carbon used greatly influence the rate of the reduction of nickel laterite. The order of reactivity is anthracite coal, lamtoro charcoal, and carbon raiser, respectively. The reductionmore » atmospheric condition also greatly influences the reduction process. The reduction process in CO{sub 2} atmospheric condition gives a lot of significant decrease in hematite and magnetite presence, means that the reduction reactions proceed more complete compared to the reduction process in the air atmospheric condition.« less

  3. Implementation of the U.S. Environmental Protection Agency's Waste Reduction (WAR) Algorithm in Cape-Open Based Process Simulators

    EPA Science Inventory

    The Sustainable Technology Division has recently completed an implementation of the U.S. EPA's Waste Reduction (WAR) Algorithm that can be directly accessed from a Cape-Open compliant process modeling environment. The WAR Algorithm add-in can be used in AmsterChem's COFE (Cape-Op...

  4. Sodium Reduction in Processed Foods in Brazil: Analysis of Food Categories and Voluntary Targets from 2011 to 2017

    PubMed Central

    Silva, Sara A.; L’Abbé, Mary; Jaime, Patricia C.

    2017-01-01

    Non-communicable diseases, including cardiovascular diseases, are responsible for over 70% of deaths in Brazil. Currently, over 25% of Brazilian adults are diagnosed as hypertensive; overall, current dietary sodium intake in Brazil (4700 mg/person) is over twice the international recommendations, and 70–90% of adolescents and adults consume excessive sodium. National sodium reduction strategies consider the main dietary sources of sodium to be added salt to foods, foods consumed outside of the household, and sodium in processed foods. The national voluntary strategy for sodium reduction in priority food categories has been continuously monitored over a 6-year period (2011–2017) and there was a significant 8–34% reduction in the average sodium content of over half food categories. Different food categories have undergone differing reductions in sodium over time, aiding gradual biannual targets to allow industries to develop new technologies and consumers to adapt to foods with less salt. By 2017, most products of all food categories had met the regional targets proposed by the Pan American Health Organization, showing that voluntary sodium reduction strategies can potentially contribute to food reformulation. Nevertheless, regulatory approaches may still be necessary in the future in order to reach all food producers and to allow stronger enforcement to meet more stringent regional targets. PMID:28704932

  5. Effect of EPS Content on Activated Sludge Reduction in Process of Predation by T. tubifex

    NASA Astrophysics Data System (ADS)

    Lei, Yingjie; Ai, Cuiling; Zhang, Guochun

    2017-12-01

    A Sludge reduction in a conventional activated sludge process combined with a membrane biofilm inoculated with T. tubifex was investigated. The influence of microbial extracellular polymeric substances (EPS) extracted in forms of LB-EPS and TB-EPS respectively on the surface properties of biomass was studied. Results showed that variations of polysaccharides and protein along with the increasing of EPS feeding would affect the existence of T. tubifex. When the amount of EPS varied from 10 to 50μg/mg, the specific resistance of a sludge suspension was obtained from 3.5×107 to 1.4×107 S2/g. Meanwhile, polysaccharides content in EPS was to be positively correlated with the SSR of sludge suspension whereas protein content would be not. Anyway, it can be argued that an increase in LB-EPS not TB-EPS may affect the performance of activated sludge reduction with efficiency about 40.1% to 31.6%.

  6. Modes of Large-Scale Brain Network Organization during Threat Processing and Posttraumatic Stress Disorder Symptom Reduction during TF-CBT among Adolescent Girls.

    PubMed

    Cisler, Josh M; Sigel, Benjamin A; Kramer, Teresa L; Smitherman, Sonet; Vanderzee, Karin; Pemberton, Joy; Kilts, Clinton D

    2016-01-01

    Posttraumatic stress disorder (PTSD) is often chronic and disabling across the lifespan. The gold standard treatment for adolescent PTSD is Trauma-Focused Cognitive-Behavioral Therapy (TF-CBT), though treatment response is variable and mediating neural mechanisms are not well understood. Here, we test whether PTSD symptom reduction during TF-CBT is associated with individual differences in large-scale brain network organization during emotion processing. Twenty adolescent girls, aged 11-16, with PTSD related to assaultive violence completed a 12-session protocol of TF-CBT. Participants completed an emotion processing task, in which neutral and fearful facial expressions were presented either overtly or covertly during 3T fMRI, before and after treatment. Analyses focused on characterizing network properties of modularity, assortativity, and global efficiency within an 824 region-of-interest brain parcellation separately during each of the task blocks using weighted functional connectivity matrices. We similarly analyzed an existing dataset of healthy adolescent girls undergoing an identical emotion processing task to characterize normative network organization. Pre-treatment individual differences in modularity, assortativity, and global efficiency during covert fear vs neutral blocks predicted PTSD symptom reduction. Patients who responded better to treatment had greater network modularity and assortativity but lesser efficiency, a pattern that closely resembled the control participants. At a group level, greater symptom reduction was associated with greater pre-to-post-treatment increases in network assortativity and modularity, but this was more pronounced among participants with less symptom improvement. The results support the hypothesis that modularized and resilient brain organization during emotion processing operate as mechanisms enabling symptom reduction during TF-CBT.

  7. Impact of the UK voluntary sodium reduction targets on the sodium content of processed foods from 2006 to 2011: analysis of household consumer panel data.

    PubMed

    Eyles, Helen; Webster, Jacqueline; Jebb, Susan; Capelin, Cathy; Neal, Bruce; Ni Mhurchu, Cliona

    2013-11-01

    In 2006 the UK Food Standards Agency (FSA) introduced voluntary sodium reduction targets for more than 80 categories of processed food. Our aim was to determine the impact of these targets on the sodium content of processed foods in the UK between 2006 and 2011. Household consumer panel data (n>18,000 households) were used to calculate crude and sales-weighted mean sodium content for 47,337 products in 2006 and 49,714 products in 2011. Two sample t-tests were used to compare means. A secondary analysis was undertaken to explore reformulation efforts and included only products available for sale in both 2006 and 2011. Between 2006 and 2011 there was an overall mean reduction in crude sodium content of UK foods of -26 mg/100g (p ≤ 0.001), equivalent to a 7% fall (356 mg/100g to 330 mg/100g). The corresponding sales-weighted reduction was -21 mg/100g (-6%). For products available for sale in both years the corresponding reduction was -23 mg/100g (p<0.001) or -7%. The UK FSA voluntary targets delivered a moderate reduction in the mean sodium content of UK processed foods between 2006 and 2011. Whilst encouraging, regular monitoring and review of the UK sodium reduction strategy will be essential to ensure continued progress. © 2013.

  8. Participant characteristics and intervention processes associated with reductions in television viewing in the High Five for Kids study

    PubMed Central

    Cespedes, Elizabeth M.; Horan, Christine M.; Gillman, Matthew W.; Gortmaker, Steven L.; Price, Sarah; Rifas-Shiman, Sheryl L.; Mitchell, Kathleen; Taveras, Elsie M.

    2014-01-01

    Objective To evaluate the High Five for Kids intervention effect on television (TV) within subgroups, examine participant characteristics associated with process measures and assess perceived helpfulness of TV intervention components. Method High Five (RCT of 445 overweight/obese 2–7 year-olds in Massachusetts [2006–2008]) reduced TV by 0.36 hours/day. 1-year effects on TV, stratified by subgroup, were assessed using linear regression. Among intervention participants (n=253), associations of intervention component helpfulness with TV reduction were examined using linear regression and associations of participant characteristics with processes linked to TV reduction (choosing TV and completing intervention visits) were examined using logistic regression. Results High Five reduced TV across subgroups. Parents of Latino (v. white) children had lower odds of completing >=2 study visits (OR 0.39 [95%CI: 0.18, 0.84]). Parents of black (v. white) children had higher odds of choosing TV (OR: 2.23 [95% CI: 1.08, 4.59]), as did parents of obese (v. overweight) children and children watching >=2 hours/day (v. <2) at baseline. Greater perceived helpfulness was associated with greater TV reduction. Conclusion Clinic-based motivational interviewing reduces TV in children. Low cost education approaches (e.g., printed materials) may be well-received. Parents of children at higher obesity risk could be more motivated to reduce TV. PMID:24518002

  9. Defense Waste Processing Facility Process Enhancements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bricker, Jonathan

    2010-11-01

    Jonathan Bricker provides an overview of process enhancements currently being done at the Defense Waste Processing Facility (DWPF) at SRS. Some of these enhancements include: melter bubblers; reduction in water use, and alternate reductant.

  10. Assessing clutter reduction in parallel coordinates using image processing techniques

    NASA Astrophysics Data System (ADS)

    Alhamaydh, Heba; Alzoubi, Hussein; Almasaeid, Hisham

    2018-01-01

    Information visualization has appeared as an important research field for multidimensional data and correlation analysis in recent years. Parallel coordinates (PCs) are one of the popular techniques to visual high-dimensional data. A problem with the PCs technique is that it suffers from crowding, a clutter which hides important data and obfuscates the information. Earlier research has been conducted to reduce clutter without loss in data content. We introduce the use of image processing techniques as an approach for assessing the performance of clutter reduction techniques in PC. We use histogram analysis as our first measure, where the mean feature of the color histograms of the possible alternative orderings of coordinates for the PC images is calculated and compared. The second measure is the extracted contrast feature from the texture of PC images based on gray-level co-occurrence matrices. The results show that the best PC image is the one that has the minimal mean value of the color histogram feature and the maximal contrast value of the texture feature. In addition to its simplicity, the proposed assessment method has the advantage of objectively assessing alternative ordering of PC visualization.

  11. Uranium isotopes fingerprint biotic reduction.

    PubMed

    Stylo, Malgorzata; Neubert, Nadja; Wang, Yuheng; Monga, Nikhil; Romaniello, Stephen J; Weyer, Stefan; Bernier-Latmani, Rizlan

    2015-05-05

    Knowledge of paleo-redox conditions in the Earth's history provides a window into events that shaped the evolution of life on our planet. The role of microbial activity in paleo-redox processes remains unexplored due to the inability to discriminate biotic from abiotic redox transformations in the rock record. The ability to deconvolute these two processes would provide a means to identify environmental niches in which microbial activity was prevalent at a specific time in paleo-history and to correlate specific biogeochemical events with the corresponding microbial metabolism. Here, we demonstrate that the isotopic signature associated with microbial reduction of hexavalent uranium (U), i.e., the accumulation of the heavy isotope in the U(IV) phase, is readily distinguishable from that generated by abiotic uranium reduction in laboratory experiments. Thus, isotope signatures preserved in the geologic record through the reductive precipitation of uranium may provide the sought-after tool to probe for biotic processes. Because uranium is a common element in the Earth's crust and a wide variety of metabolic groups of microorganisms catalyze the biological reduction of U(VI), this tool is applicable to a multiplicity of geological epochs and terrestrial environments. The findings of this study indicate that biological activity contributed to the formation of many authigenic U deposits, including sandstone U deposits of various ages, as well as modern, Cretaceous, and Archean black shales. Additionally, engineered bioremediation activities also exhibit a biotic signature, suggesting that, although multiple pathways may be involved in the reduction, direct enzymatic reduction contributes substantially to the immobilization of uranium.

  12. Microbial reductive dehalogenation.

    PubMed Central

    Mohn, W W; Tiedje, J M

    1992-01-01

    A wide variety of compounds can be biodegraded via reductive removal of halogen substituents. This process can degrade toxic pollutants, some of which are not known to be biodegraded by any other means. Reductive dehalogenation of aromatic compounds has been found primarily in undefined, syntrophic anaerobic communities. We discuss ecological and physiological principles which appear to be important in these communities and evaluate how widely applicable these principles are. Anaerobic communities that catalyze reductive dehalogenation appear to differ in many respects. A large number of pure cultures which catalyze reductive dehalogenation of aliphatic compounds are known, in contrast to only a few organisms which catalyze reductive dehalogenation of aromatic compounds. Desulfomonile tiedjei DCB-1 is an anaerobe which dehalogenates aromatic compounds and is physiologically and morphologically unusual in a number of respects, including the ability to exploit reductive dehalogenation for energy metabolism. When possible, we use D. tiedjei as a model to understand dehalogenating organisms in the above-mentioned undefined systems. Aerobes use reductive dehalogenation for substrates which are resistant to known mechanisms of oxidative attack. Reductive dehalogenation, especially of aliphatic compounds, has recently been found in cell-free systems. These systems give us an insight into how and why microorganisms catalyze this activity. In some cases transition metal complexes serve as catalysts, whereas in other cases, particularly with aromatic substrates, the catalysts appear to be enzymes. Images PMID:1406492

  13. Effects of an Advocacy Trial on Food Industry Salt Reduction Efforts—An Interim Process Evaluation

    PubMed Central

    Trevena, Helen; Petersen, Kristina; Thow, Anne Marie; Neal, Bruce

    2017-01-01

    The decisions made by food companies are a potent factor shaping the nutritional quality of the food supply. A number of non-governmental organizations (NGOs) advocate for corporate action to reduce salt levels in foods, but few data define the effectiveness of advocacy. This present report describes the process evaluation of an advocacy intervention delivered by one Australian NGO directly to food companies to reduce the salt content of processed foods. Food companies were randomly assigned to intervention (n = 22) or control (n = 23) groups. Intervention group companies were exposed to pre-planned and opportunistic communications, and control companies to background activities. Seven pre-defined interim outcome measures provided an indication of the effect of the intervention and were assessed using intention-to-treat analysis. These were supplemented by qualitative data from nine semi-structured interviews. The mean number of public communications supporting healthy food made by intervention companies was 1.5 versus 1.8 for control companies (p = 0.63). Other outcomes, including the mean number of news articles, comments and reports (1.2 vs. 1.4; p = 0.72), a published nutrition policy (23% vs. 44%; p = 0.21), public commitment to the Australian government’s Food and Health Dialogue (FHD) (41% vs. 61%; p = 0.24), evidence of a salt reduction plan (23% vs. 30%; p = 0.56), and mean number of communications with the NGO (15 vs. 11; p = 0.28) were also not significantly different. Qualitative data indicated the advocacy trial had little effect. The absence of detectable effects of the advocacy intervention on the interim markers indicates there may be no impact of the NGO advocacy trial on the primary outcome of salt reduction in processed foods. PMID:29039802

  14. Effects of an Advocacy Trial on Food Industry Salt Reduction Efforts-An Interim Process Evaluation.

    PubMed

    Trevena, Helen; Petersen, Kristina; Thow, Anne Marie; Dunford, Elizabeth K; Wu, Jason H Y; Neal, Bruce

    2017-10-17

    The decisions made by food companies are a potent factor shaping the nutritional quality of the food supply. A number of non-governmental organizations (NGOs) advocate for corporate action to reduce salt levels in foods, but few data define the effectiveness of advocacy. This present report describes the process evaluation of an advocacy intervention delivered by one Australian NGO directly to food companies to reduce the salt content of processed foods. Food companies were randomly assigned to intervention ( n = 22) or control ( n = 23) groups. Intervention group companies were exposed to pre-planned and opportunistic communications, and control companies to background activities. Seven pre-defined interim outcome measures provided an indication of the effect of the intervention and were assessed using intention-to-treat analysis. These were supplemented by qualitative data from nine semi-structured interviews. The mean number of public communications supporting healthy food made by intervention companies was 1.5 versus 1.8 for control companies ( p = 0.63). Other outcomes, including the mean number of news articles, comments and reports (1.2 vs. 1.4; p = 0.72), a published nutrition policy (23% vs. 44%; p = 0.21), public commitment to the Australian government's Food and Health Dialogue (FHD) (41% vs. 61%; p = 0.24), evidence of a salt reduction plan (23% vs. 30%; p = 0.56), and mean number of communications with the NGO (15 vs. 11; p = 0.28) were also not significantly different. Qualitative data indicated the advocacy trial had little effect. The absence of detectable effects of the advocacy intervention on the interim markers indicates there may be no impact of the NGO advocacy trial on the primary outcome of salt reduction in processed foods.

  15. Petrology of chromite in ureilites: Deconvolution of primary oxidation states and secondary reduction processes

    NASA Astrophysics Data System (ADS)

    Goodrich, Cyrena Anne; Harlow, George E.; Van Orman, James A.; Sutton, Stephen R.; Jercinovic, Michael J.; Mikouchi, Takashi

    2014-06-01

    Ureilites are ultramafic achondrites thought to be residues of partial melting on a carbon-rich asteroid. They show a trend of FeO-variation (olivine Fo from ∼74 to 95) that suggests variation in oxidation state. Whether this variation was established during high-temperature igneous processing on the ureilite parent body (UPB), or preserved from nebular precursors, is a subject of debate. The behavior of chromium in ureilites offers a way to assess redox conditions during their formation and address this issue, independent of Fo. We conducted a petrographic and mineral compositional study of occurrences of chromite (Cr-rich spinel) in ureilites, aimed at determining the origin of the chromite in each occurrence and using primary occurrences to constrain models of ureilite petrogenesis. Chromite was studied in LEW 88774 (Fo 74.2), NWA 766 (Fo 76.7), NWA 3109 (Fo 76.3), HaH 064 (Fo 77.5), LAP 03587 (Fo 74.9), CMS 04048 (Fo 76.4), LAP 02382 (Fo 78.6) and EET 96328 (Fo 85.2). Chromite occurs in LEW 88774 (∼5 vol.%), NWA 766 (<1 vol.%), NWA 3109 (<1 vol.%) and HaH 064 (<1 vol.%) as subhedral to anhedral grains comparable in size (∼30 μm to 1 mm) and/or textural setting to the major silicates (olivine and pyroxenes[s]) in each rock, indicating that it is a primary phase. The most FeO-rich chromites in these sample (rare grain cores or chadocrysts in silicates) are the most primitive compositions preserved (fe# = 0.55-0.6; Cr# varying from 0.65 to 0.72 among samples). They record olivine-chromite equilibration temperatures of ∼1040-1050 °C, reflecting subsolidus Fe/Mg reequilibration during slow cooling from ∼1200 to 1300 °C. All other chromite in these samples is reduced. Three types of zones are observed. (1) Inclusion-free interior zones showing reduction of FeO (fe# ∼0.4 → 0.28); (2) Outer zones showing further reduction of FeO (fe# ∼0.28 → 0.15) and containing abundant laths of eskolaite-corundum (Cr2O3-Al2O3); (3) Outermost zones showing extreme

  16. Characteristics and Kinetic Analysis of AQS Transformation and Microbial Goethite Reduction:Insight into "Redox mediator-Microbe-Iron oxide" Interaction Process.

    PubMed

    Zhu, Weihuang; Shi, Mengran; Yu, Dan; Liu, Chongxuan; Huang, Tinglin; Wu, Fengchang

    2016-03-29

    The characteristics and kinetics of redox transformation of a redox mediator, anthraquinone-2-sulfonate (AQS), during microbial goethite reduction by Shewanella decolorationis S12, a dissimilatory iron reduction bacterium (DIRB), were investigated to provide insights into "redox mediator-iron oxide" interaction in the presence of DIRB. Two pre-incubation reaction systems of the "strain S12- goethite" and the "strain S12-AQS" were used to investigate the dynamics of goethite reduction and AQS redox transformation. Results show that the concentrations of goethite and redox mediator, and the inoculation cell density all affect the characteristics of microbial goethite reduction, kinetic transformation between oxidized and reduced species of the redox mediator. Both abiotic and biotic reactions and their coupling regulate the kinetic process for "Quinone-Iron" interaction in the presence of DIRB. Our results provide some new insights into the characteristics and mechanisms of interaction among "quinone-DIRB- goethite" under biotic/abiotic driven.

  17. A process for quantifying aesthetic and functional breast surgery: I. Quantifying optimal nipple position and vertical and horizontal skin excess for mastopexy and breast reduction.

    PubMed

    Tebbetts, John B

    2013-07-01

    This article defines a comprehensive process using quantified parameters for objective decision making, operative planning, technique selection, and outcomes analysis in mastopexy and breast reduction, and defines quantified parameters for nipple position and vertical and horizontal skin excess. Future submissions will detail application of the processes for skin envelope design and address composite, three-dimensional parenchyma modification options. Breast base width was used to define a proportional, desired nipple-to-inframammary fold distance for optimal aesthetics. Vertical and horizontal skin excess were measured, documented, and used for technique selection and skin envelope design in mastopexy and breast reduction. This method was applied in 124 consecutive mastopexy and 122 consecutive breast reduction cases. Average follow-up was 4.6 years (range, 6 to 14 years). No changes were made to the basic algorithm of the defined process during the study period. No patient required nipple repositioning. Complications included excessive lower pole restretch (4 percent), periareolar scar hypertrophy (0.8 percent), hematoma (1.2 percent), and areola shape irregularities (1.6 percent). Delayed healing at the junction of vertical and horizontal scars occurred in two of 124 reduction patients (1.6 percent), neither of whom required revision. The overall reoperation rate was 6.5 percent (16 of 246). This study defines the first steps of a comprehensive process for using objectively defined parameters that surgeons can apply to skin envelope design for mastopexy and breast reduction. The method can be used in conjunction with, or in lieu of, other described methods to determine nipple position.

  18. Uranium isotopes fingerprint biotic reduction

    DOE PAGES

    Stylo, Malgorzata; Neubert, Nadja; Wang, Yuheng; ...

    2015-04-20

    Knowledge of paleo-redox conditions in the Earth’s history provides a window into events that shaped the evolution of life on our planet. The role of microbial activity in paleo-redox processes remains unexplored due to the inability to discriminate biotic from abiotic redox transformations in the rock record. The ability to deconvolute these two processes would provide a means to identify environmental niches in which microbial activity was prevalent at a specific time in paleo-history and to correlate specific biogeochemical events with the corresponding microbial metabolism. Here, we demonstrate that the isotopic signature associated with microbial reduction of hexavalent uranium (U),more » i.e., the accumulation of the heavy isotope in the U(IV) phase, is readily distinguishable from that generated by abiotic uranium reduction in laboratory experiments. Thus, isotope signatures preserved in the geologic record through the reductive precipitation of uranium may provide the sought-after tool to probe for biotic processes. Because uranium is a common element in the Earth’s crust and a wide variety of metabolic groups of microorganisms catalyze the biological reduction of U(VI), this tool is applicable to a multiplicity of geological epochs and terrestrial environments. The findings of this study indicate that biological activity contributed to the formation of many authigenic U deposits, including sandstone U deposits of various ages, as well as modern, Cretaceous, and Archean black shales. In addition, engineered bioremediation activities also exhibit a biotic signature, suggesting that, although multiple pathways may be involved in the reduction, direct enzymatic reduction contributes substantially to the immobilization of uranium.« less

  19. Core flooding tests to investigate the effects of IFT reduction and wettability alteration on oil recovery during MEOR process in an Iranian oil reservoir.

    PubMed

    Rabiei, Arash; Sharifinik, Milad; Niazi, Ali; Hashemi, Abdolnabi; Ayatollahi, Shahab

    2013-07-01

    Microbial enhanced oil recovery (MEOR) refers to the process of using bacterial activities for more oil recovery from oil reservoirs mainly by interfacial tension reduction and wettability alteration mechanisms. Investigating the impact of these two mechanisms on enhanced oil recovery during MEOR process is the main objective of this work. Different analytical methods such as oil spreading and surface activity measurements were utilized to screen the biosurfactant-producing bacteria isolated from the brine of a specific oil reservoir located in the southwest of Iran. The isolates identified by 16S rDNA and biochemical analysis as Enterobacter cloacae (Persian Type Culture Collection (PTCC) 1798) and Enterobacter hormaechei (PTCC 1799) produce 1.53 g/l of biosurfactant. The produced biosurfactant caused substantial surface tension reduction of the growth medium and interfacial tension reduction between oil and brine to 31 and 3.2 mN/m from the original value of 72 and 29 mN/m, respectively. A novel set of core flooding tests, including in situ and ex situ scenarios, was designed to explore the potential of the isolated consortium as an agent for MEOR process. Besides, the individual effects of wettability alteration and IFT reduction on oil recovery efficiency by this process were investigated. The results show that the wettability alteration of the reservoir rock toward neutrally wet condition in the course of the adsorption of bacteria cells and biofilm formation are the dominant mechanisms on the improvement of oil recovery efficiency.

  20. Defective Reduction in Frozen Pie Manufacturing Process

    NASA Astrophysics Data System (ADS)

    Nooted, Oranuch; Tangjitsitcharoen, Somkiat

    2017-06-01

    The frozen pie production has a lot of defects resulting in high production cost. Failure mode and effect analysis (FMEA) technique has been applied to improve the frozen pie process. Pareto chart is also used to determine the major defects of frozen pie. There are 3 main processes that cause the defects which are the 1st freezing to glazing process, the forming process, and the folding process. The Risk Priority Number (RPN) obtained from FMEA is analyzed to reduce the defects. If RPN of each cause exceeds 45, the process will be considered to be improved and selected for the corrective and preventive actions. The results showed that RPN values decreased after the correction. Therefore, the implementation of FMEA technique can help to improve the performance of frozen pie process and reduce the defects approximately 51.9%.

  1. Impact of Noise Reduction Algorithm in Cochlear Implant Processing on Music Enjoyment.

    PubMed

    Kohlberg, Gavriel D; Mancuso, Dean M; Griffin, Brianna M; Spitzer, Jaclyn B; Lalwani, Anil K

    2016-06-01

    Noise reduction algorithm (NRA) in speech processing strategy has positive impact on speech perception among cochlear implant (CI) listeners. We sought to evaluate the effect of NRA on music enjoyment. Prospective analysis of music enjoyment. Academic medical center. Normal-hearing (NH) adults (N = 16) and CI listeners (N = 9). Subjective rating of music excerpts. NH and CI listeners evaluated country music piece on three enjoyment modalities: pleasantness, musicality, and naturalness. Participants listened to the original version and 20 modified, less complex versions created by including subsets of musical instruments from the original song. NH participants listened to the segments through CI simulation and CI listeners listened to the segments with their usual speech processing strategy, with and without NRA. Decreasing the number of instruments was significantly associated with increase in the pleasantness and naturalness in both NH and CI subjects (p < 0.05). However, there was no difference in music enjoyment with or without NRA for either NH listeners with CI simulation or CI listeners across all three modalities of pleasantness, musicality, and naturalness (p > 0.05): this was true for the original and the modified music segments with one to three instruments (p > 0.05). NRA does not affect music enjoyment in CI listener or NH individual with CI simulation. This suggests that strategies to enhance speech processing will not necessarily have a positive impact on music enjoyment. However, reducing the complexity of music shows promise in enhancing music enjoyment and should be further explored.

  2. Lead recovery and glass microspheres synthesis from waste CRT funnel glasses through carbon thermal reduction enhanced acid leaching process.

    PubMed

    Mingfei, Xing; Yaping, Wang; Jun, Li; Hua, Xu

    2016-03-15

    In this study, a novel process for detoxification and reutilization of waste cathode ray tube (CRT) funnel glass was developed by carbon thermal reduction enhanced acid leaching process. The key to this process is removal of lead from the CRT funnel glass and synchronous preparation of glass microspheres. Carbon powder was used as an isolation agent and a reducing agent. Under the isolation of the carbon powder, the funnel glass powder was sintered into glass microspheres. In thermal reduction, PbO in the funnel glass was first reduced to elemental Pb by carbon monoxide and then located on the surface of glass microspheres which can be removed easily by acid leaching. Experimental results showed that temperature, carbon adding amount and holding time were the major parameters that controlled lead removal rate. The maximum lead removal rate was 94.80% and glass microspheres that measured 0.73-14.74μm were obtained successfully by setting the temperature, carbon adding amount and holding time at 1200°C, 10% and 30min, respectively. The prepared glass microspheres may be used as fillers in polymer materials and abrasive materials, among others. Accordingly, this study proposed a practical and economical process for detoxification and recycling of waste lead-containing glass. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Aerobic sulfate reduction in microbial mats

    NASA Technical Reports Server (NTRS)

    Canfield, Donald E.; Des Marais, David J.

    1991-01-01

    Measurements of bacterial sulfate reduction and dissolved oxygen (O2) in hypersaline bacterial mats from Baja California, Mexico, revealed that sulfate reduction occurred consistently within the well-oxygenated photosynthetic zone of the mats. This evidence that dissimilatory sulfate reduction can occur in the presence of O2 challenges the conventional view that sulfate reduction is a strictly anaerobic process. At constant temperature, the rates of sulfate reduction in oxygenated mats during daytime were similar to rates in anoxic mats at night: thus, during a 24-hour cycle, variations in light and O2 have little effect on rates of sulfate reduction in these mats.

  4. The Nature of Reduction in Space Weathering

    NASA Astrophysics Data System (ADS)

    McKay, D. S.; Allen, C. C.

    1993-07-01

    Space weathering is a broad term that includes a number of complex effects of the exposure of materials to the environment of space. The processes that drive space weathering include micrometeorite impact, radiation from the Sun and cosmic rays, and exposure to the vacuum of space. One of the important effects caused by these processes is the tendency for chemical reduction of oxide and silicate materials (including glasses), with accompanying loss of oxygen and production of reduced metal. Such chemical reduction and accompanying metal production may have an important influence on the chemistry of the outermost volume of individual grains as well as on the optical properties of this material. Hapke [1] discussed five processes that have been suggested for producing submicroscopic iron metal in the lunar soil: (1) shock reduction, (2) heating in a thermal blanket in vacuum, (3) shock heating of solar-wind-impregnated grains, (4) coatings deposited by solar wind sputtering, and (5) coatings deposited by impact vaporization. As noted by Hapke, "Processes (1) and (2) have been refuted by laboratory experiments. Processes (4) and (5) have produced submicroscopic iron metal in laboratory simulations. Although no experiments have been done to simulate process (3), it is widely accepted." We have been performing experimental reduction of simulated and actual lunar materials [2-5] and have shown that, under conditions of exposure to hydrogen at elevated temperatures, reduction of FeO readily occurs in ilmenite and lunar composition glass, and occurs at a slower rate in pyroxene and olivine. Even plagioclase feldspar containing minor FeO is readily reduced with formation of metallic iron blebs on surfaces [4]. A comparison of natural lunar samples to hydrogen-reduced samples or simulants in which we are searching for reduction evidence in various soil phases is underway. Preliminary data for mature soils show, in agreement with earlier results, that reduced iron produced in

  5. Removal of endocrine-disrupting chemicals and conventional pollutants in a continuous-operating activated sludge process integrated with ozonation for excess sludge reduction.

    PubMed

    Nie, Yafeng; Qiang, Zhimin; Ben, Weiwei; Liu, Junxin

    2014-06-01

    Sludge ozonation is considered as a promising technology to achieve a complete reduction of excess sludge, but as yet its effects on the removal of endocrine-disrupting chemicals (EDCs) and conventional pollutants (i.e., COD, N and P) in the activated sludge process are still unclear. In this study, two lab-scale continuous-operating activated sludge treatment systems were established: one was operated in conjunction with ozonation for excess sludge reduction, and the other was operated under normal conditions as control. The results indicate that an ozone dose of 100 mg O₃ g(-1)SS led to a zero yield of excess sludge in the sludge-reduction system during a continuous-operating period of 45d. Although ozonation gave a relatively lower specific oxygen uptake rate of activated sludge, it had little effect on the system's removal performance of COD and nitrogen substances. As a plus, sludge ozonation contributed a little more removal of target EDCs (estrone, 17β-estrodiol, estriol, 17α-ethinylestradiol, bisphenol A, and 4-nonylphenol). However, the total phosphorus removal declined notably due to its accumulation in the sludge-reduction system, which necessitates phosphorus recovery for the activated sludge process. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. A Processing-Centered Look at the Contribution of Givenness to Durational Reduction

    ERIC Educational Resources Information Center

    Kahn, Jason M.; Arnold, Jennifer E.

    2012-01-01

    Givenness tends to lead to acoustic reduction in speech, but little is known about whether linguistic and non-linguistic givenness affect reduction similarly, and there is little consensus about the underlying psychological mechanisms. We examined speakers' pronunciations of target object nouns in an instruction-giving task, where speakers saw…

  7. REDUCTION IN Pu RECOVERY PROCESSES

    DOEpatents

    Ritter, D.M.; Black, R.P.S.

    1959-09-29

    A method is described for reducing plutonium from the hexavalent to the tetravalent state in a carrier precipitation process for separating plutonium and nuclear fission products. In accordance with the invention oxalate ions are incorporated in the hexavalent plutoniumcontaining solution prior to a step of precipitating lanthanum fluoride in the solution.

  8. Organic reductants based leaching: A sustainable process for the recovery of valuable metals from spent lithium ion batteries.

    PubMed

    Chen, Xiangping; Guo, Chunxiu; Ma, Hongrui; Li, Jiazhu; Zhou, Tao; Cao, Ling; Kang, Duozhi

    2018-05-01

    It is significant to recover metal values from spent lithium ion batteries (LIBs) for the alleviation or prevention of potential risks towards environmental pollution and public health, as well as for the conservation of valuable metals. Herein a hydrometallurgical process was proposed to explore the possibility for the leaching of different metals from waste cathodic materials (LiCoO 2 ) of spent LIBs using organics as reductant in sulfuric acid medium. According to the leaching results, about 98% Co and 96% Li can be leached under the optimal experimental conditions of reaction temperature - 95 °C, reaction time - 120 min, reductive agent dosage - 0.4 g/g, slurry density - 25 g/L, concentration of sulfuric acid-3 mol/L in H 2 SO 4  + glucose leaching system. Similar results (96% Co and 100% Li) can be obtained in H 2 SO 4  + sucrose leaching system under optimized leaching conditions. Despite a complete leaching of Li (∼100%), only 54% Co can be dissolved in the H 2 SO 4  + cellulose leaching system under optimized leaching conditions. Finally, different characterization methods, including UV-Vis, FT-IR, SEM and XRD, were employed for the tentative exploration of reductive leaching reactions using organic as reductant in sulfuric acid medium. All the leaching and characterization results confirm that both glucose and sucrose are effective reductants during leaching, while cellulose should be further degraded to organics with low molecular weights to achieve a satisfactory leaching performance. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Postharvest Reduction of Coliphage MS2 from Romaine Lettuce during Simulated Commercial Processing with and without a Chlorine-Based Sanitizer.

    PubMed

    Wengert, Samantha L; Aw, Tiong Gim; Ryser, Elliot T; Rose, Joan B

    2017-02-01

    Viral foodborne outbreaks are a serious threat to public health, and fresh produce is becoming increasingly recognized as a transmission vehicle. To limit foodborne disease, ready-to-eat leafy greens are typically washed with a chlorine-based sanitizer during commercial production. This study assessed the efficacy of a chlorine-based sanitizer against coliphage MS2, as a potential surrogate for foodborne viruses, on fresh-cut romaine lettuce during simulated commercial production using a small-scale processing line. Before processing, romaine lettuce was inoculated to contain approximately 10 5 and 10 6 PFU/g of MS2 for experiments with and without sanitizer, respectively. Lettuce samples were collected following each stage of processing, which included mechanical shredding, 2 min of flume washing (with or without 25 ppm of free chlorine), shaker table dewatering, and centrifugal drying. In addition, the spent centrifuge water and flume wash water were collected, with the flume water concentrated using hollow-fiber ultrafiltration. MS2 was recovered from lettuce in Tris-glycine buffer and quantified as PFUs in a double-agar overlay assay. The greatest reduction in MS2 occurred between shredding and flume washing, with levels remaining relatively stable following flume washing with or without 25 ppm of free chlorine. Average total reductions of 0.8 and 1.0 log PFU/g were seen after processing with and without the sanitizer, respectively, with no statistical difference observed between the two treatments (P > 0.05). The average MS2 level in the spent centrifugation water started at 4.0 log PFU/ml for experiments with sanitizer and the average MS2 reduction in the flume wash water was 4 log (PFU) for experiments with sanitizer, demonstrating that removals could be achieved in the water itself. These findings suggest that the currently recommended commercial production practices are unable to effectively decrease viruses once they have attached to leafy greens during

  10. Reduction of turbidity and chromium content of tannery wastewater by electrocoagulation process.

    PubMed

    2018-02-12

    The present study is carried out to remove the chromium and turbidity from tannery wastewater by the electrocoagulationprocess with aluminum electrodes. This experimental study is performed using a batch system. The applied pilot comprises a reactor containing two parallel metal electrodes (Al). The latter are connected as mono polar and a different potential is applied between them. Several working parameters, such as applied potential difference, electrolysis time, active electrode surface, inter-electrode distance and pH of the medium have been studied to achieve higher removal efficiency.The treatment achieved a maximum reduction of 99% for the turbidity and 93% for the chromium under the following conditions: a potential difference: 15V; electrodes surface: 45cm2, inter-electrode distance: 1cm; raw water pH (6.1) and a contact time of 90 min. Considering the obtained efficiency in the present study, electrocoagulation process has the potential to be utilized for the cost-effective removal of pollutants from wastewater.

  11. Whole-leaf sanitizing wash improves chlorine efficacy for microbial reduction and prevents pathogen cross contamination during fresh-cut lettuce processing

    USDA-ARS?s Scientific Manuscript database

    Currently, nearly all fresh-cut lettuce processing facilities in the United States use chlorinated water or other sanitizer solutions for microbial reduction after lettuce is cut. It is believed that freshly cut lettuce releases significant amounts of organic matters that negatively impact the effec...

  12. An overview of advanced reduction processes for bromate removal from drinking water: Reducing agents, activation methods, applications and mechanisms.

    PubMed

    Xiao, Qian; Yu, Shuili; Li, Lei; Wang, Ting; Liao, Xinlei; Ye, Yubing

    2017-02-15

    Bromate (BrO 3 - ) is a possible human carcinogen regulated at a strict standard of 10μg/L in drinking water. Various techniques to eliminate BrO 3 - usually fall into three main categories: reducing bromide (Br - ) prior to formation of BrO 3 - , minimizing BrO 3 - formation during the ozonation process, and removing BrO 3 - from post-ozonation waters. However, the first two approaches exhibit low degradation efficiency and high treatment cost. The third workaround has obvious advantages, such as high reduction efficiency, more stable performance and easier combination with UV disinfection, and has therefore been widely implemented in water treatment. Recently, advanced reduction processes (ARPs), the photocatalysis of BrO 3 - , have attracted much attention due to improved performance. To increase the feasibility of photocatalytic systems, the focus of this work concerns new technological developments, followed by a summary of reducing agents, activation methods, operational parameters, and applications. The reaction mechanisms of two typical processes involving UV/sulfite homogeneous photocatalysis and UV/titanium dioxide heterogeneous photocatalysis are further summarized. The future research needs for ARPs to reach full-scale potential in drinking water treatment are suggested accordingly. Copyright © 2016. Published by Elsevier B.V.

  13. Characteristics and kinetic analysis of AQS transformation and microbial goethite reduction: Insight into “redox mediator-microbe-iron oxide” interaction process

    DOE PAGES

    Zhu, Weihuang; Shi, Mengran; Yu, Dan; ...

    2016-03-29

    Here, the characteristics and kinetics of redox transformation of a redox mediator, anthraquinone-2-sulfonate (AQS), during microbial goethite reduction by Shewanella decolorationis S12, a dissimilatory iron reduction bacterium (DIRB), were investigated to provide insights into “redox mediator-iron oxide” interaction in the presence of DIRB. Two pre-incubation reaction systems of the “strain S12-goethite” and the “strain S12-AQS” were used to investigate the dynamics of goethite reduction and AQS redox transformation. Results show that the concentrations of goethite and redox mediator, and the inoculation cell density all affect the characteristics of microbial goethite reduction, kinetic transformation between oxidized and reduced species of themore » redox mediator. Both abiotic and biotic reactions and their coupling regulate the kinetic process for “Quinone-Iron” interaction in the presence of DIRB. Our results provide some new insights into the characteristics and mechanisms of interaction among “quinone-DIRB- goethite” under biotic/abiotic driven.« less

  14. MS-REDUCE: an ultrafast technique for reduction of big mass spectrometry data for high-throughput processing.

    PubMed

    Awan, Muaaz Gul; Saeed, Fahad

    2016-05-15

    Modern proteomics studies utilize high-throughput mass spectrometers which can produce data at an astonishing rate. These big mass spectrometry (MS) datasets can easily reach peta-scale level creating storage and analytic problems for large-scale systems biology studies. Each spectrum consists of thousands of peaks which have to be processed to deduce the peptide. However, only a small percentage of peaks in a spectrum are useful for peptide deduction as most of the peaks are either noise or not useful for a given spectrum. This redundant processing of non-useful peaks is a bottleneck for streaming high-throughput processing of big MS data. One way to reduce the amount of computation required in a high-throughput environment is to eliminate non-useful peaks. Existing noise removing algorithms are limited in their data-reduction capability and are compute intensive making them unsuitable for big data and high-throughput environments. In this paper we introduce a novel low-complexity technique based on classification, quantization and sampling of MS peaks. We present a novel data-reductive strategy for analysis of Big MS data. Our algorithm, called MS-REDUCE, is capable of eliminating noisy peaks as well as peaks that do not contribute to peptide deduction before any peptide deduction is attempted. Our experiments have shown up to 100× speed up over existing state of the art noise elimination algorithms while maintaining comparable high quality matches. Using our approach we were able to process a million spectra in just under an hour on a moderate server. The developed tool and strategy has been made available to wider proteomics and parallel computing community and the code can be found at https://github.com/pcdslab/MSREDUCE CONTACT: : fahad.saeed@wmich.edu Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  15. Fractionation of 238U/235U by reduction during low temperature uranium mineralisation processes

    NASA Astrophysics Data System (ADS)

    Murphy, Melissa J.; Stirling, Claudine H.; Kaltenbach, Angela; Turner, Simon P.; Schaefer, Bruce F.

    2014-02-01

    Investigations of ‘stable’ uranium isotope fractionation during low temperature, redox transformations may provide new insights into the usefulness of the 238U/235U isotope system as a tracer of palaeoredox processes. Sandstone-hosted uranium deposits accumulate at an oxidation/reduction interface within an aquifer from the low temperature reduction of soluble U(VI) complexes in groundwaters, forming insoluble U(IV) minerals. This setting provides an ideal environment in which to investigate the effects of redox transformations on 238U/235U fractionation. Here we present the first coupled measurements of 238U/235U isotopic compositions and U concentrations for groundwaters and mineralised sediment samples from the same redox system in the vicinity of the high-grade Pepegoona sandstone-hosted uranium deposit, Australia. The mineralised sediment samples display extremely variable 238U/235U ratios (herein expressed as δUCRM145238, the per-mil deviation from the international NBL standard CRM145). The majority of mineralised sediment samples have δUCRM145238 values between -1.30±0.05 and 0.55±0.12‰, spanning a ca. 2‰ range. However, one sample has an unusually light isotopic composition of -4.13±0.05‰, which suggests a total range of U isotopic variability of up to ca. 5‰, the largest variation found thus far in a single natural redox system. The 238U/235U isotopic signature of the mineralised sediments becomes progressively heavier (enriched in 238U) along the groundwater flow path. The groundwaters show a greater than 2‰ variation in their 238U/235U ratios, ranging from δUCRM145238 values of -2.39±0.07 to -0.71±0.05‰. The majority of the groundwater data exhibit a clear systematic relationship between 238U/235U isotopic composition and U concentration; samples with the lowest U concentrations have the lowest 238U/235U ratios. The preferential incorporation of 238U during reduction of U(VI) to U(IV) and precipitation of uranium minerals leaves

  16. Development and validation of a ten-item questionnaire with explanatory illustrations to assess upper extremity disorders: favorable effect of illustrations in the item reduction process.

    PubMed

    Kurimoto, Shigeru; Suzuki, Mikako; Yamamoto, Michiro; Okui, Nobuyuki; Imaeda, Toshihiko; Hirata, Hitoshi

    2011-11-01

    The purpose of this study is to develop a short and valid measure for upper extremity disorders and to assess the effect of attached illustrations in item reduction of a self-administered disability questionnaire while retaining psychometric properties. A validated questionnaire used to assess upper extremity disorders, the Hand20, was reduced to ten items using two item-reduction techniques. The psychometric properties of the abbreviated form, the Hand10, were evaluated on an independent sample that was used for the shortening process. Validity, reliability, and responsiveness of the Hand10 were retained in the item reduction process. It was possible that the use of explanatory illustrations attached to the Hand10 helped with its reproducibility. The illustrations for the Hand10 promoted text comprehension and motivation to answer the items. These changes resulted in high acceptability; more than 99.3% of patients, including 98.5% of elderly patients, could complete the Hand10 properly. The illustrations had favorable effects on the item reduction process and made it possible to retain precision of the instrument. The Hand10 is a reliable and valid instrument for individual-level applications with the advantage of being compact and broadly applicable, even in elderly individuals.

  17. Synthesis and characterization of TiC nanopowders via sol-gel and subsequent carbothermal reduction process

    NASA Astrophysics Data System (ADS)

    Chen, Xu; Fan, Jinglian; Lu, Qiong

    2018-06-01

    TiC nanocrystalline powders were synthesized by in-situ carbothermic reduction of Ti-O-C precursor under vacuum atmosphere. And the Ti-O-C precursor was formed by sol-gel method from titanium butyrate (TBOT) and sucrose. To obtain stable sol, TBOT was directly added into mixed solution which contains water, sucrose, acetic acid (AcOH) and acetylacetone (ACAC). This procedure is more convenient and economical because it avoids the use of alcohol which is used as solvent in most reports of alkoxide hydrolysis sol-gel method. TG-DSC, XRD, FTIR and SEM/TEM were employed to analyze and characterize the product during the entire process. The phase composition and crystalline structure parameters of powders with different C/Ti molar ratio were investigated by Rietveld refinement method, and elemental quantitative analysis of the samples were performed. Furthermore, the optimal parameters of carbothermal reduction were obtained and the grain growth mechanism was demonstrated. The results show that TiC nanocrystalline powders (C/Ti molar ratio is 3.5 in the precursor) were synthesized at 1300 °C for 2 h, which have near standard lattice parameter, well crystallinity and fine average grain size ( 37.4 nm).

  18. Model reduction in integrated controls-structures design

    NASA Technical Reports Server (NTRS)

    Maghami, Peiman G.

    1993-01-01

    It is the objective of this paper to present a model reduction technique developed for the integrated controls-structures design of flexible structures. Integrated controls-structures design problems are typically posed as nonlinear mathematical programming problems, where the design variables consist of both structural and control parameters. In the solution process, both structural and control design variables are constantly changing; therefore, the dynamic characteristics of the structure are also changing. This presents a problem in obtaining a reduced-order model for active control design and analysis which will be valid for all design points within the design space. In other words, the frequency and number of the significant modes of the structure (modes that should be included) may vary considerably throughout the design process. This is also true as the locations and/or masses of the sensors and actuators change. Moreover, since the number of design evaluations in the integrated design process could easily run into thousands, any feasible order-reduction method should not require model reduction analysis at every design iteration. In this paper a novel and efficient technique for model reduction in the integrated controls-structures design process, which addresses these issues, is presented.

  19. Treatment and toxicity reduction of textile dyeing wastewater using the electrocoagulation-electroflotation process.

    PubMed

    Kim, Han-Lae; Cho, Jong-Bok; Park, Yong-Jin; Cho, Il-Hyoung

    2016-07-02

    A pilot-scale study was conducted using the electrocoagulation-electroflotation (EC-EF) process to treat textile dyeing raw wastewater to evaluate treatment performance. The effects of some key factors, such as current density, hydraulic retention time (HRT), and removal of conductivity, total suspended solids (TSS), chemical oxygen demand (COD), and color were investigated. The operating variables were current density of 0-300 A m(-2), HRT of 0-30 min, and a coagulant (anionic polyacrylamide (A-PAM)) dosage of 0-30 mg L(-1). Daphnia magna was used to test acute toxicity in raw and treated wastewater. Under the operating conditions without added coagulant, maxima of 51%, 88%, 84%, and 99% of conductivity, TSS, COD, and color were removed, respectively, with a HRT of 30 min. The coagulant enhanced removal of all wastewater parameters. Removal maxima of 59%, 92%, 94%, and 98% for conductivity, TSS, COD, and color were observed, respectively, with an optimal dosage of 30 mg L(-1) and a shortened HRT of 20 min. The 48 h-LC50 D. magna test showed that the raw wastewater was highly toxic. However, the EC-EF process decreased toxicity of the treated samples significantly, and >70% toxicity reduction was achieved by the EC-EF process with the addition of 15-30 mg L(-1) coagulant, HRT of 20 min, and current density of 150-300 A m(-2). The pilot scale test (0.3 m(3 )h(-1)) shows that the EC-EF process with added coagulant effectively treated textile dyeing wastewater.

  20. Nonlinear system identification of the reduction nickel oxide smelting process in electric arc furnace

    NASA Astrophysics Data System (ADS)

    Gubin, V.; Firsov, A.

    2018-03-01

    As the title implies the article describes the nonlinear system identification of the reduction smelting process of nickel oxide in electric arc furnaces. It is suggested that for operational control ratio of components of the charge must be solved the problem of determining the qualitative composition of the melt in real time. The use of 0th harmonic of phase voltage AC furnace as an indirect measure of the melt composition is proposed. Brief description of the mechanism of occurrence and nature of the non-zero 0th harmonic of the AC voltage of the arc is given. It is shown that value of 0th harmonic of the arc voltage is not function of electrical parameters but depends of the material composition of the melt. Processed industrial data are given. Hammerstein-Wiener model is used for description of the dependence of 0th harmonic of the furnace voltage from the technical parameters of melting furnace: the melt composition and current. Recommendations are given about the practical use of the model.

  1. Regularized Embedded Multiple Kernel Dimensionality Reduction for Mine Signal Processing.

    PubMed

    Li, Shuang; Liu, Bing; Zhang, Chen

    2016-01-01

    Traditional multiple kernel dimensionality reduction models are generally based on graph embedding and manifold assumption. But such assumption might be invalid for some high-dimensional or sparse data due to the curse of dimensionality, which has a negative influence on the performance of multiple kernel learning. In addition, some models might be ill-posed if the rank of matrices in their objective functions was not high enough. To address these issues, we extend the traditional graph embedding framework and propose a novel regularized embedded multiple kernel dimensionality reduction method. Different from the conventional convex relaxation technique, the proposed algorithm directly takes advantage of a binary search and an alternative optimization scheme to obtain optimal solutions efficiently. The experimental results demonstrate the effectiveness of the proposed method for supervised, unsupervised, and semisupervised scenarios.

  2. Enhancement of Efficiency and Reduction of Grid Thickness Variation on Casting Process with Lean Six Sigma Method

    NASA Astrophysics Data System (ADS)

    Witantyo; Setyawan, David

    2018-03-01

    In a lead acid battery industry, grid casting is a process that has high defect and thickness variation level. DMAIC (Define-Measure-Analyse-Improve-Control) method and its tools will be used to improve the casting process. In the Define stage, it is used project charter and SIPOC (Supplier Input Process Output Customer) method to map the existent problem. In the Measure stage, it is conducted a data retrieval related to the types of defect and the amount of it, also the grid thickness variation that happened. And then the retrieved data is processed and analyzed by using 5 Why’s and FMEA method. In the Analyze stage, it is conducted a grid observation that experience fragile and crack type of defect by using microscope showing the amount of oxide Pb inclusion in the grid. Analysis that is used in grid casting process shows the difference of temperature that is too high between the metal fluid and mold temperature, also the corking process that doesn’t have standard. The Improve stage is conducted a fixing process which generates the reduction of grid variation thickness level and defect/unit level from 9,184% to 0,492%. In Control stage, it is conducted a new working standard determination and already fixed control process.

  3. Selective catalytic reduction system and process for control of NO.sub.x emissions in a sulfur-containing gas stream

    DOEpatents

    Sobolevskiy, Anatoly

    2015-08-11

    An exhaust gas treatment process, apparatus, and system for reducing the concentration of NOx, CO and hydrocarbons in a gas stream, such as an exhaust stream (29), via selective catalytic reduction with ammonia is provided. The process, apparatus and system include a catalytic bed (32) having a reducing only catalyst portion (34) and a downstream reducing-plus-oxidizing portion (36). Each portion (34, 36) includes an amount of tungsten. The reducing-plus-oxidizing catalyst portion (36) advantageously includes a greater amount of tungsten than the reducing catalyst portion (36) to markedly limit ammonia salt formation.

  4. WORKSHOP ON MONITORING OXIDATION-REDUCTION PROCESSES FOR GROUND-WATER RESTORATION

    EPA Science Inventory

    Redox conditions are among the most important parameters for controlling contaminant transport and fate in ground-water systems. Oxidation-reduction (redox) reactions mediate the chemical behavior of both inorganic and organic chemical constituents by affecting solubility, rea...

  5. Reduction of aerobic and lactic acid bacteria in dairy desludge using an integrated compressed CO2 and ultrasonic process.

    PubMed

    Overton, Tim W; Lu, Tiejun; Bains, Narinder; Leeke, Gary A

    Current treatment routes are not suitable to reduce and stabilise bacterial content in some dairy process streams such as separator and bactofuge desludges which currently present a major emission problem faced by dairy producers. In this study, a novel method for the processing of desludge was developed. The new method, elevated pressure sonication (EPS), uses a combination of low frequency ultrasound (20 kHz) and elevated CO 2 pressure (50 to 100 bar). Process conditions (pressure, sonicator power, processing time) were optimised for batch and continuous EPS processes to reduce viable numbers of aerobic and lactic acid bacteria in bactofuge desludge by ≥3-log fold. Coagulation of proteins present in the desludge also occurred, causing separation of solid (curd) and liquid (whey) fractions. The proposed process offers a 10-fold reduction in energy compared to high temperature short time (HTST) treatment of milk.

  6. Analysis of holding time variations to Ni and Fe content and morphology in nickel laterite limonitic reduction process by using coal-dolomite bed

    NASA Astrophysics Data System (ADS)

    Abdul, Fakhreza; Pintowantoro, Sungging; Yuwandono, Ridwan Bagus

    2018-04-01

    With the depletion of nickel sulfide ore resources, the nickel laterit processing become an attention to fulfill nickel world demans. Reducing laterite nickel by using a low cost carbonaceous reductan has proved produces high grade ferronickel alloy. In this research, reduction was carried out to low grade laterite nickel (limonite) with 1.25% nikel content by using CO gas reductant formed by reaction between coal and dolomite. Reduction process preceded by forming brickets mixture from limonit ore, coal, and Na2SO4, then the brickets placed inside crucible bed together with dolomit and reduced at temperature 1400 °C with holding time variations 4, 6, and 8 hours. EDX, XRD, and SEM test were carried out to find out the Ni and nickel grade after reduced, the phases that formed, and the morphology brickets after reduced. The reduction results shows that the highest increase on nickel grade was obtained by 8 hours holding time increasing 5.84 % from initial grade, and the highest recovery was obtained by 6 hours holding time with recovery 88.51 %. While the higest increase on Fe grade was obtained by 4 hours holding time, and the highest recovery Fe was obtained by 4 hours holding time with recovery 85.41%.

  7. Thermodynamics of lunar ilmenite reduction

    NASA Technical Reports Server (NTRS)

    Altenberg, B. H.; Franklin, H. A.; Jones, C. H.

    1993-01-01

    With the prospect of returning to the moon, the development of a lunar occupation would fulfill one of the goals of the Space Exploration Initiative (SEI) of the late 1980's. Processing lunar resources into useful products, such as liquid oxygen for fuel and life support, would be one of many aspects of an active lunar base. ilmenite (FeTiO3) is found on the lunar surface and can be used as a feed stock to produce oxygen. Understanding the various ilmenite-reduction reactions elucidates many processing options. Defining the thermodynamic chemical behavior at equilibrium under various conditions of temperature and pressures can be helpful in specifying optimal operating conditions. Differences between a previous theoretical analysis and experimentally determined results has sparked interest in trying to understand the effect of operating pressure on the hydrogen-reduction-of-ilmenite reaction. Various aspects of this reduction reaction are discussed.

  8. The effect of sodium hydroxide on drag reduction using banana peel as a drag reduction agent

    NASA Astrophysics Data System (ADS)

    Kaur, H.; Jaafar, A.

    2018-02-01

    Drag reduction is observed as reduced frictional pressure losses under turbulent flow conditions. Drag reduction agent such as polymers can be introduced to increase the flowrate of water flowing and reduce the water accumulation in the system. Currently used polymers are synthetic polymers, which will harm our environment in excessive use of accumulation. A more environmentally-friendly drag reduction agent such as the polymer derived from natural sources or biopolymer, is then required for such purpose. As opposed to the synthetic polymers, the potential of biopolymers as drag reduction agents, especially those derived from a local plant source are not extensively explored. The drag reduction of a polymer produced from a local plant source within the turbulent regime was explored and assessed in this study using a rheometer, where a reduced a torque produced was perceived as a reduction of drag. This method proposed is less time consuming and is more practical which is producing carboxymethylcellulose from the banana peel. The cellulose powder was converted to carboxymethylcellulose (CMC) by etherification process. The carboxymethylation reaction during the synthesizing process was then optimized against the reaction temperature, reaction time and solubility. The biopolymers were then rheologically characterized, where the viscoelastic effects and the normal stresses produced by these biopolymers were utilized to further relate and explain the drag reduction phenomena. The research was structured to focus on producing the biopolymer and to assess the drag reduction ability of the biopolymer produced. The rheological behavior of the biopolymers was then analyzed based on the ability of reducing drag. The results are intended to expand the currently extremely limited experimental database. Based on the results, the biopolymer works as a good DRA.

  9. Single Crystal Casting with Fluidized Carbon Bed Cooling: A Process Innovation for Quality Improvement and Cost Reduction

    NASA Astrophysics Data System (ADS)

    Hofmeister, M.; Franke, M. M.; Koerner, C.; Singer, R. F.

    2017-12-01

    Superalloy gas turbine blades are being produced by investment casting and directional solidification. A new process, Fluidized Carbon Bed Cooling (FCBC), has been developed and is now being optimized in a prototype casting unit with 10 kg pouring weight. In early test runs with still rather simple mold cluster geometries, a reduction of the primary dendrite arm spacing of around 40 pct compared to the standard radiation cooling process (HRS) could be demonstrated. The improvement is mainly attributed to higher temperature gradients driving solidification, made possible by a functioning Dynamic Baffle. Compared to earlier development efforts in the literature, contamination of the melt and damage to the equipment are avoided using carbon-based fluidized bed materials and the so-called "counter pressure concept."

  10. Dissimilatory perchlorate reduction: a review.

    PubMed

    Bardiya, Nirmala; Bae, Jae-Ho

    2011-05-20

    In the United States anthropogenic activities are mainly responsible for the wide spread perchlorate contamination of drinking water, surface water, groundwater, and soil. Even at microgram levels, perchlorate causes toxicity to flora and fauna and affects growth, metabolism and reproduction in humans and animals. Reports of antithyroid effects of perchlorate and its detection in common food items have raised serious public health concerns, leading to extensive decontamination efforts in recent years. Several physico-chemical removal and biological decontamination processes are being developed. Although promising, ion exchange is a non-selective and incomplete process as it merely transfers perchlorate from water to the resin. The perchlorate-laden spent resins (perchlorate 200-500 mg L(-1)) require regeneration resulting in production of concentrated brine (6-12% NaCl) or caustic waste streams. On the contrary, biological reduction completely degrades perchlorate into O(2) and innocuous Cl(-). High reduction potential of ClO(4)(-)/Cl(-) (E° =∼ 1.28 V) and ClO(3)(-)/Cl(-) pairs (E° =1.03 V) makes these contaminants thermodynamically ideal e(-) acceptors for microbial reduction. In recent years unique dissimilatory perchlorate reducing bacteria have been isolated and detailed studies pertaining to their microbiological, biochemical, genetics and phylogenetic aspects have been undertaken which is the subject of this review article while the various physico-chemical removal and biological reduction processes have been reviewed by others. Copyright © 2010 Elsevier GmbH. All rights reserved.

  11. The Gemini Recipe System: a dynamic workflow for automated data reduction

    NASA Astrophysics Data System (ADS)

    Labrie, Kathleen; Allen, Craig; Hirst, Paul; Holt, Jennifer; Allen, River; Dement, Kaniela

    2010-07-01

    Gemini's next generation data reduction software suite aims to offer greater automation of the data reduction process without compromising the flexibility required by science programs using advanced or unusual observing strategies. The Recipe System is central to our new data reduction software. Developed in Python, it facilitates near-real time processing for data quality assessment, and both on- and off-line science quality processing. The Recipe System can be run as a standalone application or as the data processing core of an automatic pipeline. The data reduction process is defined in a Recipe written in a science (as opposed to computer) oriented language, and consists of a sequence of data reduction steps, called Primitives, which are written in Python and can be launched from the PyRAF user interface by users wishing to use them interactively for more hands-on optimization of the data reduction process. The fact that the same processing Primitives can be run within both the pipeline context and interactively in a PyRAF session is an important strength of the Recipe System. The Recipe System offers dynamic flow control allowing for decisions regarding processing and calibration to be made automatically, based on the pixel and the metadata properties of the dataset at the stage in processing where the decision is being made, and the context in which the processing is being carried out. Processing history and provenance recording are provided by the AstroData middleware, which also offers header abstraction and data type recognition to facilitate the development of instrument-agnostic processing routines.

  12. Interaction of abiotic and microbial processes in hexachloroethane reduction in groundwater

    USGS Publications Warehouse

    Roberts, A. Lynn; Gschwend, Philip M.

    1994-01-01

    In order to gain insight into mechanisms of hexachloroethane reduction, hexa- and pentachloroethane transformation rates were measured in anaerobic groundwater samples. For samples spiked with pentachloroethane, disappearance of pentachloroethane was accompanied by tetrachloroethylene production. Transformation rates were similar in unpoisoned and in HgCl2-poisoned samples, and rates were within ±20% of predictions based on measured pH and second-order dehydrochlorination rate constants determined in clean laboratory systems, indicating that the fate of pentachloroethane in this system is dominated by abiotic reactions. No hexachloroethane transformation was observed in HgCl2-poisoned samples, whereas in unpoisoned samples, hexachloroethane disappearance was accompanied by production of tetrachloroethylene as well as traces of pentachloroethane. Although only minor amounts of pentachloroethane accumulated, as much as 30% of the hexachloroethane transformation pathway proceeds via a pentachloroethane intermediate. This suggests that the microbial reduction of hexachloroethane proceeds at least in part through a free-radical mechanism. To the extent that hexachloroethane reduction to tetrachloroethylene occurs through a pentachloroethane intermediate, the first step in the sequence, the microbially-mediated step, is the slow step; the subsequent abiotic dehydrohalogenation step occurs much more rapidly.

  13. Experimental Investigation on Reduction Kinetics of Stainless Steel-Making Slag in Iron Bath Smelting Reduction

    NASA Astrophysics Data System (ADS)

    Zhang, Bo; Liu, Jienan; Yang, Yanfeng; Liu, Luming; Liu, Jiechao; Luo, Lijian; Ma, Yubao; Hong, Xin

    Reduction kinetics of stainless steel slag in iron bath smelting reduction was studied at the temperature of 1500°C ˜ 1650°C. It was concluded that the reduction process consisted of two parts. That is to say smelting reduction was controlled by stainless steel slag melting initially and by interface reaction later. In order to increase smelting reaction rate, the melting point of slag should be decreased at the first stage and adjust the liquidity of slag at later stage. Smelting reaction rate will be accelerated by means of optimize the slag content. The optimal reduction result that all most all of the chromium in slag been recovered was obtained in temperature was 1500°C, basicity of slag was 1.0˜1.2, the value of Al2O3+MgO was 25%.

  14. Implementation of a Community-Based Secondhand Smoke Reduction Intervention for Caregivers of Urban Children with Asthma: Process Evaluation, Successes and Challenges

    ERIC Educational Resources Information Center

    Blaakman, Susan; Tremblay, Paul J.; Halterman, Jill S.; Fagnano, Maria; Borrelli, Belinda

    2013-01-01

    Many children, including those with asthma, remain exposed to secondhand smoke. This manuscript evaluates the process of implementing a secondhand smoke reduction counseling intervention using motivational interviewing (MI) for caregivers of urban children with asthma, including reach, dose delivered, dose received and fidelity. Challenges,…

  15. TREATMENT OF HEXAVALENT CHROMIUM IN CHROMITE ORE PROCESSING SOLID WASTE USING A MIXED REDUCTANT SOLUTION OF FERROUS SULFATE AND SODIUM DITHIONITE

    EPA Science Inventory

    We developed a method for disseminating ferrous iron in the subsurface to enhance chemical reduction of hexavalent chromium (Cr(VI)) in a chromite ore processing solid waste derived from the production of ferrochrome alloy. The method utilizes ferrous sulfate (FeSO4) in combinati...

  16. Influence of dihydroxybenzenes on paracetamol and ciprofloxacin degradation and iron(III) reduction in Fenton processes.

    PubMed

    Costa E Silva, Beatriz; de Lima Perini, João Angelo; Nogueira, Raquel F Pupo

    2017-03-01

    The degradation of paracetamol (PCT) and ciprofloxacin (CIP) was compared in relation to the generation of dihydroxylated products, Fe(III) reduction and reaction rate in the presence of dihydroxybenzene (DHB) compounds, or under irradiation with free iron (Fe 3+ ) or citrate complex (Fecit) in Fenton or photo-Fenton process. The formation of hydroquinone (HQ) was observed only during PCT degradation in the dark, which increased drastically the rate of PCT degradation, since HQ formed was able to reduce Fe 3+ and contributed to PCT degradation efficiency. When HQ was initially added, PCT and CIP degradation rate in the dark was much higher in comparison to the absence of HQ, due to the higher and faster formation of Fe 2+ at the beginning of reaction. In the absence of HQ, no CIP degradation was observed; however, when HQ was added after 30 min, the degradation rate increased drastically. Ten PCT hydroxylated intermediates were identified in the absence of HQ, which could contribute for Fe(III) reduction and consequently to the degradation in a similar way as HQ. During CIP degradation, only one product of hydroxyl radical attack on benzene ring and substitution of the fluorine atom was identified when HQ was added to the reaction medium.

  17. SU-D-209-03: Radiation Dose Reduction Using Real-Time Image Processing in Interventional Radiology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kanal, K; Moirano, J; Zamora, D

    Purpose: To characterize changes in radiation dose after introducing a new real-time image processing technology in interventional radiology systems. Methods: Interventional radiology (IR) procedures are increasingly complex, at times requiring substantial time and radiation dose. The risk of inducing tissue reactions as well as long-term stochastic effects such as radiation-induced cancer is not trivial. To reduce this risk, IR systems are increasingly equipped with dose reduction technologies.Recently, ClarityIQ (Philips Healthcare) technology was installed in our existing neuroradiology IR (NIR) and vascular IR (VIR) suites respectively. ClarityIQ includes real-time image processing that reduces noise/artifacts, enhances images, and sharpens edges while alsomore » reducing radiation dose rates. We reviewed 412 NIR (175 pre- and 237 post-ClarityIQ) procedures and 329 VIR (156 preand 173 post-ClarityIQ) procedures performed at our institution pre- and post-ClarityIQ implementation. NIR procedures were primarily classified as interventional or diagnostic. VIR procedures included drain port, drain placement, tube change, mesenteric, and implanted venous procedures. Air Kerma (AK in units of mGy) was documented for all the cases using a commercial radiation exposure management system. Results: When considering all NIR procedures, median AK decreased from 1194 mGy to 561 mGy. When considering all VIR procedures, median AK decreased from 49 to 14 mGy. Both NIR and VIR exhibited a decrease in AK exceeding 50% after ClarityIQ implementation, a statistically significant (p<0.05) difference. Of the 5 most common VIR procedures, all median AK values decreased, but significance (p<0.05) was only reached in venous access (N=53), angio mesenteric (N=41), and drain placement procedures (N=31). Conclusion: ClarityIQ can reduce dose significantly for both NIR and VIR procedures. Image quality was not assessed in conjunction with the dose reduction.« less

  18. TiO2 Processed by pressurized hot solvents as a novel photocatalyst for photocatalytic reduction of carbon dioxide

    NASA Astrophysics Data System (ADS)

    Reli, Martin; Kobielusz, Marcin; Matějová, Lenka; Daniš, Stanislav; Macyk, Wojciech; Obalová, Lucie; Kuśtrowski, Piotr; Rokicińska, Anna; Kočí, Kamila

    2017-01-01

    Anatase-brookite TiO2 photocatalysts were prepared by the sol-gel process controlled within reverse micelles and processing by pressurized hot solvents-water/methanol/water (TiO2(M)) and water/ethanol/water (TiO2(E)), as an unconventional alternative to common calcination. The main goal of this work was to prepare anatase-brookite mixtures by processing by two different alcohols (methanol and ethanol) and evaluate the influence of the alcohol on the photocatalytic activity. Prepared photocatalysts were characterized by organic elemental analysis, nitrogen physisorption, XRD, UV-vis, photoelectrochemical and spectroelectrochemical measurements and XPS. The prepared photocatalysts efficiency was tested on the photocatalytic reduction of carbon dioxide and compared with commercial TiO2 Evonik P25. Both prepared nanocomposites were more efficient towards methane production but Evonik P25 was the most efficient towards hydrogen generated through water splitting. The higher performance of anatase-brookite mixture towards methane production can be explained by (i) a higher photocatalytic activity of brookite than rutile; (ii) a large surface area of anatase-brookite composites enabling better carbon dioxide adsorption; (iii) the photoinduced electron transfer from the brookite conduction band to the anatase conduction band. On the other hand, a higher production of hydrogen in the presence of Evonik P25 is caused by a better charge separation in anatase-rutile than anatase-brookite phase compositions. TiO2(M) appeared more active than TiO2(E) in the photocatalytic reduction of carbon dioxide due to a lower density of defects created in the crystal lattice.

  19. Sex-work harm reduction.

    PubMed

    Rekart, Michael L

    2005-12-17

    Sex work is an extremely dangerous profession. The use of harm-reduction principles can help to safeguard sex workers' lives in the same way that drug users have benefited from drug-use harm reduction. Sex workers are exposed to serious harms: drug use, disease, violence, discrimination, debt, criminalisation, and exploitation (child prostitution, trafficking for sex work, and exploitation of migrants). Successful and promising harm-reduction strategies are available: education, empowerment, prevention, care, occupational health and safety, decriminalisation of sex workers, and human-rights-based approaches. Successful interventions include peer education, training in condom-negotiating skills, safety tips for street-based sex workers, male and female condoms, the prevention-care synergy, occupational health and safety guidelines for brothels, self-help organisations, and community-based child protection networks. Straightforward and achievable steps are available to improve the day-to-day lives of sex workers while they continue to work. Conceptualising and debating sex-work harm reduction as a new paradigm can hasten this process.

  20. Carbene-catalysed reductive coupling of nitrobenzyl bromides and activated ketones or imines via single-electron-transfer process

    PubMed Central

    Li, Bao-Sheng; Wang, Yuhuang; Proctor, Rupert S. J.; Zhang, Yuexia; Webster, Richard D.; Yang, Song; Song, Baoan; Chi, Yonggui Robin

    2016-01-01

    Benzyl bromides and related molecules are among the most common substrates in organic synthesis. They are typically used as electrophiles in nucleophilic substitution reactions. These molecules can also be activated via single-electron-transfer (SET) process for radical reactions. Representative recent progress includes α-carbon benzylation of ketones and aldehydes via photoredox catalysis. Here we disclose the generation of (nitro)benzyl radicals via N-heterocyclic carbene (NHC) catalysis under reductive conditions. The radical intermediates generated via NHC catalysis undergo formal 1,2-addition with ketones to eventually afford tertiary alcohol products. The overall process constitutes a formal polarity-inversion of benzyl bromide, allowing a direct coupling of two initially electrophilic carbons. Our study provides a new carbene-catalysed reaction mode that should enable unconventional transformation of (nitro)benzyl bromides under mild organocatalytic conditions. PMID:27671606

  1. Carbene-catalysed reductive coupling of nitrobenzyl bromides and activated ketones or imines via single-electron-transfer process

    NASA Astrophysics Data System (ADS)

    Li, Bao-Sheng; Wang, Yuhuang; Proctor, Rupert S. J.; Zhang, Yuexia; Webster, Richard D.; Yang, Song; Song, Baoan; Chi, Yonggui Robin

    2016-09-01

    Benzyl bromides and related molecules are among the most common substrates in organic synthesis. They are typically used as electrophiles in nucleophilic substitution reactions. These molecules can also be activated via single-electron-transfer (SET) process for radical reactions. Representative recent progress includes α-carbon benzylation of ketones and aldehydes via photoredox catalysis. Here we disclose the generation of (nitro)benzyl radicals via N-heterocyclic carbene (NHC) catalysis under reductive conditions. The radical intermediates generated via NHC catalysis undergo formal 1,2-addition with ketones to eventually afford tertiary alcohol products. The overall process constitutes a formal polarity-inversion of benzyl bromide, allowing a direct coupling of two initially electrophilic carbons. Our study provides a new carbene-catalysed reaction mode that should enable unconventional transformation of (nitro)benzyl bromides under mild organocatalytic conditions.

  2. Evaluation of virus reduction efficiency in wastewater treatment unit processes as a credit value in the multiple-barrier system for wastewater reclamation and reuse.

    PubMed

    Ito, Toshihiro; Kato, Tsuyoshi; Hasegawa, Makoto; Katayama, Hiroyuki; Ishii, Satoshi; Okabe, Satoshi; Sano, Daisuke

    2016-12-01

    The virus reduction efficiency of each unit process is commonly determined based on the ratio of virus concentration in influent to that in effluent of a unit, but the virus concentration in wastewater has often fallen below the analytical quantification limit, which does not allow us to calculate the concentration ratio at each sampling event. In this study, left-censored datasets of norovirus (genogroup I and II), and adenovirus were used to calculate the virus reduction efficiency in unit processes of secondary biological treatment and chlorine disinfection. Virus concentration in influent, effluent from the secondary treatment, and chlorine-disinfected effluent of four municipal wastewater treatment plants were analyzed by a quantitative polymerase chain reaction (PCR) approach, and the probabilistic distributions of log reduction (LR) were estimated by a Bayesian estimation algorithm. The mean values of LR in the secondary treatment units ranged from 0.9 and 2.2, whereas those in the free chlorine disinfection units were from -0.1 and 0.5. The LR value in the secondary treatment was virus type and unit process dependent, which raised the importance for accumulating the data of virus LR values applicable to the multiple-barrier system, which is a global concept of microbial risk management in wastewater reclamation and reuse.

  3. Quantitative evaluation of photoplethysmographic artifact reduction for pulse oximetry

    NASA Astrophysics Data System (ADS)

    Hayes, Matthew J.; Smith, Peter R.

    1999-01-01

    Motion artefact corruption of pulse oximeter output, causing both measurement inaccuracies and false alarm conditions, is a primary restriction in the current clinical practice and future applications of this useful technique. Artefact reduction in photoplethysmography (PPG), and therefore by application in pulse oximetry, is demonstrated using a novel non-linear methodology recently proposed by the authors. The significance of these processed PPG signals for pulse oximetry measurement is discussed, with particular attention to the normalization inherent in the artefact reduction process. Quantitative experimental investigation of the performance of PPG artefact reduction is then utilized to evaluate this technology for application to pulse oximetry. While the successfully demonstrated reduction of severe artefacts may widen the applicability of all PPG technologies and decrease the occurrence of pulse oximeter false alarms, the observed reduction of slight artefacts suggests that many such effects may go unnoticed in clinical practice. The signal processing and output averaging used in most commercial oximeters can incorporate these artefact errors into the output, while masking the true PPG signal corruption. It is therefore suggested that PPG artefact reduction should be incorporated into conventional pulse oximetry measurement, even in the absence of end-user artefact problems.

  4. Reduction of Chlorate by Iron Mediated Processes: Implications for Oxy-Chlorine Species on Mars and Earth

    NASA Astrophysics Data System (ADS)

    Brundrett, M.; Yan, W.; Jackson, W. A.

    2017-12-01

    Studies have confirmed the presence of chlorate (ClO3-) and perchlorate (ClO4-) in terrestrial systems, lunar regolith, Martian surface soils, and meteorites [1, 2, 4]. A roughly equimolar ratio of ClO3- : ClO4- has been observed for most systems with the only major exceptions the Antarctica dry valley soils (MDV) and Martian surface material, where the ClO3- : ClO4- ratios are significantly less than 1 [3, 4]. All known ClO4- production mechanisms produce molar ratios of ClO3-: ClO4- equal to or greater than 1 [5]. Post depositional processes may explain the potential reduction of ClO3-. The objective of this study was to determine the potential abiotic transformation of ClO3- by Fe (II)-bearing minerals, similar to known reactions between NO3- and Fe (II) minerals. The presence of iron-derived minerals has been established in the MDV, Martian soils, and chondrite meteorites. Batch experiments were conducted by reacting four Fe (II)-bearing minerals (wustite, siderite, magnetite, and green rust) with ClO3- at various pH (4.5, 6.5, 8.9). Chlorate reduction was rapid (half-life on the order of hours to days) and generally ClO3- was quantitatively converted to Cl-. Results of this study will increase our understanding of surface reactions that produced and transformed oxy-chlorine compounds on Mars elucidating past and present Martian surface conditions. The study also has implications into the understanding of the evolutionary processes that previously or currently dictate the abiotic geochemical processing of oxy-chlorine anions through terrestrial systems. [1] Jackson et al. (2015) EPSL 430, 470-476. [2] Rao et al. (2010) ES&T 44, 8429-8434. [3] Jackson et al. (2010) ES&T 44, 4869-4876. [4] Hecht et al. (2009) SCI 325, 64-67. [5] Rao et al. (2010) ES&T 44, 2961-2967.

  5. Microwave enhanced chemical reduction process for nitrite-containing wastewater treatment using sulfaminic acid.

    PubMed

    Li, Nan; Wang, Peng; Liu, Qingsong; Cao, Hailei

    2010-01-01

    High-concentration nitrite-containing wastewater that presents extreme toxicity to human health and organisms is difficult to be treated using traditional biological process. In this study, a novel microwave-enhanced chemical reduction process (MECRP) using sulfaminic acid (SA) was proposed as a new manner to treat such type of wastewater. Based on lab-scale experiments, it was shown that 75%-80% nitrite (NO2-) could be removed within time as short as 4 min under 50 W microwave irradiation in pH range 5-10 when molar ratio of SA to nitrite (SA/NO2-) was 0.8. Pilot-scale investigations demonstrated that MECRP was able to achieve nitrite and chemical oxygen demand (COD) removal with efficiency up to 80% and 20%, respectively under operating conditions of SA concentration 80 kg/m3, SA/NO2- ratio 0.8, microwave power 3.4 kW, and stirring time 3 min. Five-day biological oxygen demand (BOD5)/COD value of treated effluent after MECRP was increased from 0.05 to 0.36 (by 620%), which clearly suggested a considerable improvement of biodegradability for subsequent biological treatment. This study provided a demonstration of using microwave irradiation to enhance reaction between SA and nitrite in a short time, in which nitrite in wastewater was completely converted into nitrogen gas without leaving any sludge and secondary pollutants.

  6. Challenges and Recent Developments in Hearing Aids: Part II. Feedback and Occlusion Effect Reduction Strategies, Laser Shell Manufacturing Processes, and Other Signal Processing Technologies

    PubMed Central

    Chung, King

    2004-01-01

    This is the second part of a review on the challenges and recent developments in hearing aids. Feedback and the occlusion effect pose great challenges in hearing aid design and usage. Yet, conventional solutions to feedback and the occlusion effect often create a dilemma: the solution to one often leads to the other. This review discusses the advanced signal processing strategies to reduce feedback and some new approaches to reduce the occlusion effect. Specifically, the causes of three types of feedback (acoustic, mechanical, and electromagnetic) are discussed. The strategies currently used to reduce acoustic feedback (i.e., adaptive feedback reduction algorithms using adaptive gain reduction, notch filtering, and phase cancellation strategies) and the design of new receivers that are built to reduce mechanical and electromagnetic feedback are explained. In addition, various new strategies (i.e., redesigned sound delivery devices and receiver-in-the-ear-canal hearing aid configuration) to reduce the occlusion effect are reviewed. Many manufacturers have recently adopted laser shell-manufacturing technologies to overcome problems associated with manufacturing custom hearing aid shells. The mechanisms of selected laser sintering and stereo lithographic apparatus and the properties of custom shells produced by these two processes are reviewed. Further, various new developments in hearing aid transducers, telecoils, channel-free amplification, open-platform programming options, rechargeable hearing aids, ear-level frequency modulated (FM) receivers, wireless Bluetooth FM systems, and wireless programming options are briefly explained and discussed. Finally, the applications of advanced hearing aid technologies to enhance other devices such as cochlear implants, hearing protectors, and cellular phones are discussed. PMID:15735871

  7. Defective Reduction in Automotive Headlining Manufacturing Process

    NASA Astrophysics Data System (ADS)

    Rittichai, Saranya; Chutima, Parames

    2016-05-01

    In an automobile parts manufacturing company, currently the headlining process has a lot of wastes resulting in a high cost of quality per year. In this paper, the Six Sigma method is used to reduce the defects in the headlining process. Cause-and-effect matrix and failure mode and effect analysis (FMEA) were adopted to screen the factors that affect the quality of headlining. The 2k-1 fractional factorials design was also use to determine the potential preliminary root causes. The full factorial experiments was conducted to identify appropriate settings of the significant factors. The result showed that the process can reduce the defects of headlining from 12.21% to 6.95%

  8. Budget Reduction in the Navy

    DTIC Science & Technology

    1990-12-01

    process; (4) the degree efbudgetary responsiveness in DOD/DON cutback budgeting to criteria developed from two theoretical models of fical reduction... developed from two theoretical models of fiscal reduction methodology. |V ..... A A,’ 4 . 0 f .; . . Dis Apm a al@r Di3t I peala iii, TARLK Or COUTENS...accompanying reshaping of U.S. forces include a continuation of the positive developments in Eastern Europe and the Soviet Union, completion of

  9. Crystallographic texture and earing behavior analysis for different second cold reductions of double-reduction tinplate

    NASA Astrophysics Data System (ADS)

    Liao, Lu-hai; Zheng, Xiao-fei; Kang, Yong-lin; Liu, Wei; Yan, Yan; Mo, Zhi-ying

    2018-06-01

    Since the production of tinplate with non-earing properties is difficult, especially when it is produced via the double-reduction process, the optimal degree of second cold reduction is particularly important for achieving desirable drawing properties. The evolution of texture and the earing propensity of double-reduction tinplate with different extents of second reduction were investigated in this study. Optical microscopy and scanning electron microscopy were used to observe the changes in the microstructure at various extents of reduction. Two common testing methods, X-ray diffraction (XRD) and electron backscatter diffraction, were used to investigate the texture of the specimens, which revealed the effects of deformation percentage on the final texture development and the change in the grain boundary. The earing rate was determined via earing tests involving measurement of the height of any ear. The results obtained from both XRD analyses and earing tests revealed the same ideal value for the second cold reduction on the basis of the relationship between crystallographic texture and the degree of earing.

  10. The Gemini Recipe System: A Dynamic Workflow for Automated Data Reduction

    NASA Astrophysics Data System (ADS)

    Labrie, K.; Hirst, P.; Allen, C.

    2011-07-01

    Gemini's next generation data reduction software suite aims to offer greater automation of the data reduction process without compromising the flexibility required by science programs using advanced or unusual observing strategies. The Recipe System is central to our new data reduction software. Developed in Python, it facilitates near-real time processing for data quality assessment, and both on- and off-line science quality processing. The Recipe System can be run as a standalone application or as the data processing core of an automatic pipeline. Building on concepts that originated in ORAC-DR, a data reduction process is defined in a Recipe written in a science (as opposed to computer) oriented language, and consists of a sequence of data reduction steps called Primitives. The Primitives are written in Python and can be launched from the PyRAF user interface by users wishing for more hands-on optimization of the data reduction process. The fact that the same processing Primitives can be run within both the pipeline context and interactively in a PyRAF session is an important strength of the Recipe System. The Recipe System offers dynamic flow control allowing for decisions regarding processing and calibration to be made automatically, based on the pixel and the metadata properties of the dataset at the stage in processing where the decision is being made, and the context in which the processing is being carried out. Processing history and provenance recording are provided by the AstroData middleware, which also offers header abstraction and data type recognition to facilitate the development of instrument-agnostic processing routines. All observatory or instrument specific definitions are isolated from the core of the AstroData system and distributed in external configuration packages that define a lexicon including classifications, uniform metadata elements, and transformations.

  11. High-purity nano particles ZnS production by a simple coupling reaction process of biological reduction and chemical precipitation mediated with EDTA.

    PubMed

    Xin, Baoping; Huang, Qun; Chen, Shi; Tang, Xuemei

    2008-01-01

    High-purity nanoparticles ZnS has been successfully synthesized using a simple coupling reaction process of biological reduction and chemical precipitation mediated with EDTA referred to as the CRBRCP-EDTA process. This research investigated the optimum conditions of the transformation of SO(4) (2-) into S(2-) by SRB, and the production of ZnS in the CRBRCP-EDTA process. The results showed that the molar ratio of Zn(2+) to EDTA = 1:1 was crucial for SRB growth and ZnS synthesis. At the ratio(n) (Zn2+)/n) (EDTA) = 1:1, lower Zn(2+) concentration enhanced both the growth of SRB and the reduction of SO(4) (2-), leading to higher ZnS production. Although increase in Na(2)SO(4) concentration resulted in decrease in both SRB growth and SO(4) (2-) reduction, it improved the S(2-) and ZnS production. Under the optimum conditions (0.05 mol L(-1) ZnCl(2), 0.05 mol L(-1) EDTA, and 0.1 mol L(-1) Na(2)SO(4)), the synthesized ZnS was characterized by X-ray diffraction (XRD), X-ray energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The analysis showed that the obtained ZnS were high-purity and well-distributed solid spheres with diameters of about 15 nm for primary particles and around 400 nm for secondary particles. When polyacrylamide (PAM) was incorporated in the CRBRCP-EDTA process, the secondary particle's diameters were reduced to less than 100 nm. The photoluminescence (PL) spectra of produced ZnS centered at 396 nm, the spectrum with PAM added showed the gradual increase in absorption and stronger intensity in PL property. The present simple, low-cost, and safe method may be extended to prepare other metal-sulfide nanocomposites.

  12. Magnesium fluoride reduction-vessel liners. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Latham-Brown, C.E.

    1986-03-26

    The work described in this report details a program that demonstrated a method by which magnesium fluoride, the by-product of the reduction reaction of uranium tetrafluoride to uranium metal could be used to replace the present graphite used to line the reduction vessel. Utilization of magnesium fluoride (MgF2) as a reduction-vessel liner has the potential to decrease carbon contamination and thereby reduce DU derby rejects due to chemistry. Additionally, there would be the elimination of the cost of the graphite crucible liner and the associated disposal costs by replacement with the by-product of the reduction reaction, which is magnesium fluoride.more » The process would ultimately result in reduced manufacturing costs for derby metal and higher yield of finished penetrators. This was to be accomplished in such a manner as to produce uranium metal derbies which would be accommodated into the present Nuclear Metals-Carolina Metals penetrator production process with minimal changes in equipment and procedures.« less

  13. Iodine retention during evaporative volume reduction

    DOEpatents

    Godbee, H.W.; Cathers, G.I.; Blanco, R.E.

    1975-11-18

    An improved method for retaining radioactive iodine in aqueous waste solutions during volume reduction is disclosed. The method applies to evaporative volume reduction processes whereby the decontaminated (evaporated) water can be returned safely to the environment. The method generally comprises isotopically diluting the waste solution with a nonradioactive iodide and maintaining the solution at a high pH during evaporation.

  14. In-situ sludge reduction and carbon reuse in an anoxic/oxic process coupled with hydrocyclone breakage.

    PubMed

    Xu, Yinxiang; Fang, Yuanyuan; Wang, Zhenhua; Guo, Dan; Liu, Yi; Huang, Yuan; Fu, Pengbo; Jin, Juehui; Wei, Chenwen; Wang, Hualin; Zeng, Tao

    2018-05-09

    The long-term performance of an anoxic-oxic-hydrocyclone (AOH) process with an in-situ hydrocyclone treatment unit in the mixed liquid return line for sludge reduction and carbon reuse has been observed, in comparison with a conventional anoxic-oxic (AO) process. Three parallel side-stream systems, including one AOH 25 system with a 25-mm hydrocyclone, one AOH 35 system with a 35-mm hydrocyclone and one AO system, were built and fed with real wastewater for a comparative study in a wastewater treatment plant. The results demonstrate that the hydrocyclone in the AOH process was able to break macro-flocs into smaller flocs. And the desorption of the extracellular polymeric substance from return activated sludge (AS) leaded to an average increase of 62.97% and 36.36% in SCOD in the AOH 25 and AOH 35 system, respectively. In addition, shear forces, centrifugal forces of revolution and flocs' rotation in the hydrocyclone were proposed to be the main influence mechanism of hydrocyclone treatment on AS properties. Compared with the AO process, the SCOD concentration in the effluent of the AOH processes presented a decrease of 12.0 mg/L and the TN was reduced by 21.50% owing to the released carbon sources reuse. Moreover, the sludge production was reduced by 36.81% and 35.92% in the AOH 25 and AOH 35 process, respectively. By contrast, the AOH 25 system was better than the AOH 35 system. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Apparatus and process for the electrolytic reduction of uranium and plutonium oxides

    DOEpatents

    Poa, David S.; Burris, Leslie; Steunenberg, Robert K.; Tomczuk, Zygmunt

    1991-01-01

    An apparatus and process for reducing uranium and/or plutonium oxides to produce a solid, high-purity metal. The apparatus is an electrolyte cell consisting of a first container, and a smaller second container within the first container. An electrolyte fills both containers, the level of the electrolyte in the first container being above the top of the second container so that the electrolyte can be circulated between the containers. The anode is positioned in the first container while the cathode is located in the second container. Means are provided for passing an inert gas into the electrolyte near the lower end of the anode to sparge the electrolyte and to remove gases which form on the anode during the reduction operation. Means are also provided for mixing and stirring the electrolyte in the first container to solubilize the metal oxide in the electrolyte and to transport the electrolyte containing dissolved oxide into contact with the cathode in the second container. The cell is operated at a temperature below the melting temperature of the metal product so that the metal forms as a solid on the cathode.

  16. Delivering data reduction pipelines to science users

    NASA Astrophysics Data System (ADS)

    Freudling, Wolfram; Romaniello, Martino

    2016-07-01

    The European Southern Observatory has a long history of providing specialized data processing algorithms, called recipes, for most of its instruments. These recipes are used for both operational purposes at the observatory sites, and for data reduction by the scientists at their home institutions. The two applications require substantially different environments for running and controlling the recipes. In this papers, we describe the ESOReflex environment that is used for running recipes on the users' desktops. ESOReflex is a workflow driven data reduction environment. It allows intuitive representation, execution and modification of the data reduction workflow, and has facilities for inspection of and interaction with the data. It includes fully automatic data organization and visualization, interaction with recipes, and the exploration of the provenance tree of intermediate and final data products. ESOReflex uses a number of innovative concepts that have been described in Ref. 1. In October 2015, the complete system was released to the public. ESOReflex allows highly efficient data reduction, using its internal bookkeeping database to recognize and skip previously completed steps during repeated processing of the same or similar data sets. It has been widely adopted by the science community for the reduction of VLT data.

  17. High-performance Bi-stage process in reduction of graphene oxide for transparent conductive electrodes

    NASA Astrophysics Data System (ADS)

    Alahbakhshi, Masoud; Fallahi, Afsoon; Mohajerani, Ezeddin; Fathollahi, Mohammad-Reza; Taromi, Faramarz Afshar; Shahinpoor, Mohsen

    2017-02-01

    A novel and innovative approach to develop reduction of graphene oxide (GO) solution for fabrication of highly and truly transparent conductive electrode (TCE) has been presented. Thanks to outstanding mechanical and electronic properties of graphene which offer practical applications in synthesizing composites as well as fabricating various optoelectronic devices, in this study, conductive reduced graphene oxide (r-GO) thin films were prepared through sequential chemical and thermal reduction process of homogeneously dispersed GO solutions. The conductivity and transparency of r-GO thin film is regulated using hydroiodic acid (HI) as reducing agent following by vacuum thermal annealing. The prepared r-GO is characterized by XRD, AFM, UV-vis and Raman spectroscopy. the AFM topographic images reveal surface roughness almost ∼11 nm which became less than 2 nm for the 4 mg/mL solution. Moreover, XRD analysis and Raman spectra substantiate the interlayer spacing between rGO layers has been reduced dramatically and also electronic conjugation has been ameliorated after using HI chemical agent and 700 °C thermal annealing sequentially. Subsequently providing r-GO transparent electrode with decent and satisfactory transparency, acceptable conductivity and suitable work function, it has been exploited as the anode in organic light emitting diode (OLED). The maximum luminance efficiency and maximum power efficiency reached 4.2 cd/A and 0.83 lm/W, respectively. We believe that by optimizing the hole density, sheet resistance, transparency and surface morphology of the r-GO anodes, the device efficiencies can be remarkably increased further.

  18. Microbial reduction of iron ore

    DOEpatents

    Hoffmann, Michael R.; Arnold, Robert G.; Stephanopoulos, Gregory

    1989-01-01

    A process is provided for reducing iron ore by treatment with microorganisms which comprises forming an aqueous mixture of iron ore, microorganisms operable for reducing the ferric iron of the iron ore to ferrous iron, and a substrate operable as an energy source for the microbial reduction; and maintaining the aqueous mixture for a period of time and under conditions operable to effect the reduction of the ore. Preferably the microorganism is Pseudomonas sp. 200 and the reduction conducted anaerobically with a domestic wastewater as the substrate. An aqueous solution containing soluble ferrous iron can be separated from the reacted mixture, treated with a base to precipitate ferrous hydroxide which can then be recovered as a concentrated slurry.

  19. On the connection between multigrid and cyclic reduction

    NASA Technical Reports Server (NTRS)

    Merriam, M. L.

    1984-01-01

    A technique is shown whereby it is possible to relate a particular multigrid process to cyclic reduction using purely mathematical arguments. This technique suggest methods for solving Poisson's equation in 1-, 2-, or 3-dimensions with Dirichlet or Neumann boundary conditions. In one dimension the method is exact and, in fact, reduces to cyclic reduction. This provides a valuable reference point for understanding multigrid techniques. The particular multigrid process analyzed is referred to here as Approximate Cyclic Reduction (ACR) and is one of a class known as Multigrid Reduction methods in the literature. It involves one approximation with a known error term. It is possible to relate the error term in this approximation with certain eigenvector components of the error. These are sharply reduced in amplitude by classical relaxation techniques. The approximation can thus be made a very good one.

  20. Comparative studies on single-layer reduced graphene oxide films obtained by electrochemical reduction and hydrazine vapor reduction

    NASA Astrophysics Data System (ADS)

    Wang, Zhijuan; Wu, Shixin; Zhang, Juan; Chen, Peng; Yang, Guocheng; Zhou, Xiaozhu; Zhang, Qichun; Yan, Qingyu; Zhang, Hua

    2012-02-01

    The comparison between two kinds of single-layer reduced graphene oxide (rGO) sheets, obtained by reduction of graphene oxide (GO) with the electrochemical method and hydrazine vapor reduction, referred to as E-rGO and C-rGO, respectively, is systematically studied. Although there is no morphology difference between the E-rGO and C-rGO films adsorbed on solid substrates observed by AFM, the reduction process to obtain the E-rGO and C-rGO films is quite different. In the hydrazine vapor reduction, the nitrogen element is incorporated into the obtained C-rGO film, while no additional element is introduced to the E-rGO film during the electrochemical reduction. Moreover, Raman spectra show that the electrochemical method is more effective than the hydrazine vapor reduction method to reduce the GO films. In addition, E-rGO shows better electrocatalysis towards dopamine than does C-rGO. This study is helpful for researchers to understand these two different reduction methods and choose a suitable one to reduce GO based on their experimental requirements.

  1. Fuzzy Relational Databases: Representational Issues and Reduction Using Similarity Measures.

    ERIC Educational Resources Information Center

    Prade, Henri; Testemale, Claudette

    1987-01-01

    Compares and expands upon two approaches to dealing with fuzzy relational databases. The proposed similarity measure is based on a fuzzy Hausdorff distance and estimates the mismatch between two possibility distributions using a reduction process. The consequences of the reduction process on query evaluation are studied. (Author/EM)

  2. The problem of modeling the process of air blowing through finely perforated wall for skin friction reduction

    NASA Astrophysics Data System (ADS)

    Kornilov, V. I.; Boiko, A. V.

    2017-10-01

    Problems of experimental modeling of the process of air blowing into turbulent boundary layer of incompressible fluid through finely perforated wall are discussed. Particular attention is paid to the analysis of both the main factors responsible for the effectiveness of blowing and the possibility of studying the factors in artificially generated turbulent boundary layer. It was shown that uniformity of the injected gas is one of the main requirements to enhance the effectiveness of this method of flow control. An example of the successful application of this technology exhibiting a significant reduction of the turbulent skin friction is provided.

  3. Development and validation of a building design waste reduction model.

    PubMed

    Llatas, C; Osmani, M

    2016-10-01

    Reduction in construction waste is a pressing need in many countries. The design of building elements is considered a pivotal process to achieve waste reduction at source, which enables an informed prediction of their wastage reduction levels. However the lack of quantitative methods linking design strategies to waste reduction hinders designing out waste practice in building projects. Therefore, this paper addresses this knowledge gap through the design and validation of a Building Design Waste Reduction Strategies (Waste ReSt) model that aims to investigate the relationships between design variables and their impact on onsite waste reduction. The Waste ReSt model was validated in a real-world case study involving 20 residential buildings in Spain. The validation process comprises three stages. Firstly, design waste causes were analyzed. Secondly, design strategies were applied leading to several alternative low waste building elements. Finally, their potential source reduction levels were quantified and discussed within the context of the literature. The Waste ReSt model could serve as an instrumental tool to simulate designing out strategies in building projects. The knowledge provided by the model could help project stakeholders to better understand the correlation between the design process and waste sources and subsequently implement design practices for low-waste buildings. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. The Synergy of Class Size Reduction and Classroom Quality

    ERIC Educational Resources Information Center

    Graue, Elizabeth; Rauscher, Erica; Sherfinski, Melissa

    2009-01-01

    A contextual approach to understanding class size reduction includes attention to both educational inputs and processes. Based on our study of a class size reduction program in Wisconsin we explore the following question: How do class size reduction and classroom quality interact to produce learning opportunities in early elementary classrooms? To…

  5. Preparation of Pt Nanocatalyst on Carbon Materials via a Reduction Reaction of a Pt Precursor in a Drying Process.

    PubMed

    Lee, Jae-Young; Lee, Woo-Kum; Rim, Hyung-Ryul; Joung, Gyu-Bum; Weidner, John W; Lee, Hong-Ki

    2016-06-01

    Platinum (Pt) nanocatalyst for a proton-exchange membrane fuel cell (PEMFC) was prepared on a carbon black particle or a graphite particle coated with a nafion polymer via a reduction of platinum(II) bis(acetylacetonate) denoted as Pt(acac)2 as a Pt precursor in a drying process. Sublimed Pt(acac)2 adsorbed on the nafion-coated carbon materials was reduced to Pt nanoparticles in a glass reactor at 180 degrees C of N2 atmosphere. The morphology of Pt nanoparticles on carbon materials was observed by scanning electron microscopy (SEM) and the distribution of Pt nanoparticles was done by transmission electron microscopy (TEM). The particle size was estimated by analyzing the TEM image using an image analyzer. It was found that nano-sized Pt particles were deposited on the surface of carbon materials, and the number density and the average particle size increased with increasing reduction time.

  6. Dissimilatory Fe(III) and Mn(IV) reduction.

    PubMed Central

    Lovley, D R

    1991-01-01

    The oxidation of organic matter coupled to the reduction of Fe(III) or Mn(IV) is one of the most important biogeochemical reactions in aquatic sediments, soils, and groundwater. This process, which may have been the first globally significant mechanism for the oxidation of organic matter to carbon dioxide, plays an important role in the oxidation of natural and contaminant organic compounds in a variety of environments and contributes to other phenomena of widespread significance such as the release of metals and nutrients into water supplies, the magnetization of sediments, and the corrosion of metal. Until recently, much of the Fe(III) and Mn(IV) reduction in sedimentary environments was considered to be the result of nonenzymatic processes. However, microorganisms which can effectively couple the oxidation of organic compounds to the reduction of Fe(III) or Mn(IV) have recently been discovered. With Fe(III) or Mn(IV) as the sole electron acceptor, these organisms can completely oxidize fatty acids, hydrogen, or a variety of monoaromatic compounds. This metabolism provides energy to support growth. Sugars and amino acids can be completely oxidized by the cooperative activity of fermentative microorganisms and hydrogen- and fatty-acid-oxidizing Fe(III) and Mn(IV) reducers. This provides a microbial mechanism for the oxidation of the complex assemblage of sedimentary organic matter in Fe(III)- or Mn(IV)-reducing environments. The available evidence indicates that this enzymatic reduction of Fe(III) or Mn(IV) accounts for most of the oxidation of organic matter coupled to reduction of Fe(III) and Mn(IV) in sedimentary environments. Little is known about the diversity and ecology of the microorganisms responsible for Fe(III) and Mn(IV) reduction, and only preliminary studies have been conducted on the physiology and biochemistry of this process. PMID:1886521

  7. Linear and crosslinked Polyurethanes based catalysts for reduction of methylene blue.

    PubMed

    Sultan, Misbah; Javeed, Asma; Uroos, Maliha; Imran, Muhammad; Jubeen, Farhat; Nouren, Shazia; Saleem, Nazish; Bibi, Ismat; Masood, Rashid; Ahmed, Waqas

    2018-02-15

    The large amount of synthetic dyes in effluents is a serious concern to be addressed. The chemical reduction is one of the potential way to resolve this problem. In this study, linear and crosslinked polyurethanes i.e. LPUR & CLPUR were synthesized from toluene diisocyanate (TDI), polyethylene glycol (PEG;1000g/mole) and tetraethylenepentamine (TEPA). The structure and morphology of synthesized materials were examined by FTIR, SEM and BET. The CLPUR was found stable in aqueous system with 0.80g/cm 3 density and 16.4998m 2 g -1 surface area. These materials were applied for the reduction of methylene blue in presence of NaBH 4 . Both, polymers catalyzed the process and showed 100% reduction in 16 and 28mins., respectively, while, the reduction rate was significantly low in absence of these materials, even after 120mins. Furthermore, negligible adsorption was observed with only 7% removal of dye. The best reduction rates were observed at low concentration of dye, increasing concentration of NaBH 4 and with more dosage of polymeric catalyst. The kinetic study of process followed zero order kinetics. It was hence concluded that both synthesized polymers played a catalytic role in reduction process. However, stability in aqueous system and better efficiency in reduction process endorsed CLPUR as an optimal choice for further studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Toxics Use Reduction to Achieve Enhanced Pollution Prevention Success

    EPA Pesticide Factsheets

    Training material from the Massachusetts Toxics Use Reduction Institute, University of Massachusetts Lowell. This training explains toxic use reduction, process mapping and materials accounting. Helps identify TUR opportunities and TUR options evaluation

  9. Microbial reduction of iron ore

    DOEpatents

    Hoffmann, M.R.; Arnold, R.G.; Stephanopoulos, G.

    1989-11-14

    A process is provided for reducing iron ore by treatment with microorganisms which comprises forming an aqueous mixture of iron ore, microorganisms operable for reducing the ferric iron of the iron ore to ferrous iron, and a substrate operable as an energy source for the microbial reduction; and maintaining the aqueous mixture for a period of time and under conditions operable to effect the reduction of the ore. Preferably the microorganism is Pseudomonas sp. 200 and the reduction conducted anaerobically with a domestic wastewater as the substrate. An aqueous solution containing soluble ferrous iron can be separated from the reacted mixture, treated with a base to precipitate ferrous hydroxide which can then be recovered as a concentrated slurry. 11 figs.

  10. Nagel on reduction.

    PubMed

    Sarkar, Sahotra

    2015-10-01

    This paper attempts a critical reappraisal of Nagel's (1961, 1970) model of reduction taking into account both traditional criticisms and recent defenses. This model treats reduction as a type of explanation in which a reduced theory is explained by a reducing theory after their relevant representational items have been suitably connected. In accordance with the deductive-nomological model, the explanation is supposed to consist of a logical deduction. Nagel was a pluralist about both the logical form of the connections between the reduced and reducing theories (which could be conditionals or biconditionals) and their epistemological status (as analytic connections, conventions, or synthetic claims). This paper defends Nagel's pluralism on both counts and, in the process, argues that the multiple realizability objection to reductionism is misplaced. It also argues that the Nagel model correctly characterizes reduction as a type of explanation. However, it notes that logical deduction must be replaced by a broader class of inferential techniques that allow for different types of approximation. Whereas Nagel (1970), in contrast to his earlier position (1961), recognized the relevance of approximation, he did not realize its full import for the model. Throughout the paper two case studies are used to illustrate the arguments: the putative reduction of classical thermodynamics to the kinetic theory of matter and that of classical genetics to molecular biology. Copyright © 2015. Published by Elsevier Ltd.

  11. Open Reduction in Pediatric Condylar Fracture.

    PubMed

    Barbosa, Alexandre Agostini; Mariano, Ronaldo Célio

    2017-05-01

    Facial fractures in children are rare. Lack of pneumatization, fat pockets, mixed dentition, contribute to the elasticity and bone stability. When mandibular fractures occur in children, most often involve the condyle by indirect trauma. Such fractures are the center of discussion on the form of treatment if this should be performed conservatively, or held the reduction and fixation of the fracture with surgical exposure of the fragments. In condylar fractures in children, in most patients, the proposed treatment is closed reduction. Treatment with open reduction and fixation has its specific indications. In this case, the authors report a patient cycling accident victim, with cut-contusion injury in ment with limited mouth opening and left condylar fracture with medial rotation. The treatment was the reduction and fixation of fragments by open process.

  12. Tensor integrand reduction via Laurent expansion

    NASA Astrophysics Data System (ADS)

    Hirschi, Valentin; Peraro, Tiziano

    2016-06-01

    We introduce a new method for the application of one-loop integrand reduction via the Laurent expansion algorithm, as implemented in the public C ++ library N inja. We show how the coefficients of the Laurent expansion can be computed by suitable contractions of the loop numerator tensor with cut-dependent projectors, making it possible to interface N inja to any one-loop matrix element generator that can provide the components of this tensor. We implemented this technique in the N inja library and interfaced it to M adL oop, which is part of the public M adG raph5_ aMC@NLO framework. We performed a detailed performance study, comparing against other public reduction tools, namely C utT ools, S amurai, IREGI, PJF ry++ and G olem95. We find that N inja out-performs traditional integrand reduction in both speed and numerical stability, the latter being on par with that of the tensor integral reduction tool Golem95 which is however more limited and slower than N inja. We considered many benchmark multi-scale processes of increasing complexity, involving QCD and electro-weak corrections as well as effective non-renormalizable couplings, showing that N inja's performance scales well with both the rank and multiplicity of the considered process.

  13. Spectral Data Reduction via Wavelet Decomposition

    NASA Technical Reports Server (NTRS)

    Kaewpijit, S.; LeMoigne, J.; El-Ghazawi, T.; Rood, Richard (Technical Monitor)

    2002-01-01

    The greatest advantage gained from hyperspectral imagery is that narrow spectral features can be used to give more information about materials than was previously possible with broad-band multispectral imagery. For many applications, the new larger data volumes from such hyperspectral sensors, however, present a challenge for traditional processing techniques. For example, the actual identification of each ground surface pixel by its corresponding reflecting spectral signature is still one of the most difficult challenges in the exploitation of this advanced technology, because of the immense volume of data collected. Therefore, conventional classification methods require a preprocessing step of dimension reduction to conquer the so-called "curse of dimensionality." Spectral data reduction using wavelet decomposition could be useful, as it does not only reduce the data volume, but also preserves the distinctions between spectral signatures. This characteristic is related to the intrinsic property of wavelet transforms that preserves high- and low-frequency features during the signal decomposition, therefore preserving peaks and valleys found in typical spectra. When comparing to the most widespread dimension reduction technique, the Principal Component Analysis (PCA), and looking at the same level of compression rate, we show that Wavelet Reduction yields better classification accuracy, for hyperspectral data processed with a conventional supervised classification such as a maximum likelihood method.

  14. EXTERIOR VIEW, LOOKING EAST, OF REDUCTION PLANT NO. 6 WITH ...

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

    EXTERIOR VIEW, LOOKING EAST, OF REDUCTION PLANT NO. 6 WITH PRIMARY AND SECONDARY LIMESTONE REDUCTION ('CRUSHING') IN PROGRESS. FEEDER (RIGHT) FEEDS TO CONVEYOR BELTS (CENTER) AND CRUSHER (LEFT). LIMESTONE PROCESSED THROUGH THIS OPERATION IS FURTHER SCREENED AND PROCESSED AT ANOTHER PLANT ON THE THOMAS SITE. OPERATION OF THIS PLANT, WHICH BEGAN IN 1960, INCORPORATES WITHIN THE FEEDER A CONCRETE RETAINING WALL DATING TO A TURN OF THE CENTURY QUARRY OPERATION FORMERLY ON THIS SITE. - Wade Sand & Gravel Company, Reduction Plant No. 6, State Route 78, Thomas, Jefferson County, AL

  15. On the analysis of the double Hopf bifurcation in machining processes via centre manifold reduction

    NASA Astrophysics Data System (ADS)

    Molnar, T. G.; Dombovari, Z.; Insperger, T.; Stepan, G.

    2017-11-01

    The single-degree-of-freedom model of orthogonal cutting is investigated to study machine tool vibrations in the vicinity of a double Hopf bifurcation point. Centre manifold reduction and normal form calculations are performed to investigate the long-term dynamics of the cutting process. The normal form of the four-dimensional centre subsystem is derived analytically, and the possible topologies in the infinite-dimensional phase space of the system are revealed. It is shown that bistable parameter regions exist where unstable periodic and, in certain cases, unstable quasi-periodic motions coexist with the equilibrium. Taking into account the non-smoothness caused by loss of contact between the tool and the workpiece, the boundary of the bistable region is also derived analytically. The results are verified by numerical continuation. The possibility of (transient) chaotic motions in the global non-smooth dynamics is shown.

  16. Defining Constellation Suit Helmet Field of View Requirements Employing a Mission Segment Based Reduction Process

    NASA Technical Reports Server (NTRS)

    McFarland, Shane

    2009-01-01

    Field of view has always been a design feature paramount to helmets, and in particular space suits, where the helmet must provide an adequate field of view for a large range of activities, environments, and body positions. For Project Constellation, a different approach to helmet requirement maturation was utilized; one that was less a direct function of body position and suit pressure and more a function of the mission segment in which the field of view will be required. Through taxonimization of various parameters that affect suited field of view, as well as consideration for possible nominal and contingency operations during that mission segment, a reduction process was employed to condense the large number of possible outcomes to only six unique field of view angle requirements that still captured all necessary variables while sacrificing minimal fidelity.

  17. Implementation of a community-based secondhand smoke reduction intervention for caregivers of urban children with asthma: process evaluation, successes and challenges

    PubMed Central

    Blaakman, Susan; Tremblay, Paul J.; Halterman, Jill S.; Fagnano, Maria; Borrelli, Belinda

    2013-01-01

    Many children, including those with asthma, remain exposed to secondhand smoke. This manuscript evaluates the process of implementing a secondhand smoke reduction counseling intervention using motivational interviewing (MI) for caregivers of urban children with asthma, including reach, dose delivered, dose received and fidelity. Challenges, strategies and successes in applying MI are highlighted. Data for 140 children (3–10 years) enrolled in the School Based Asthma Therapy trial, randomized to the treatment condition and living with one or more smoker, were analyzed. Summary statistics describe the sample, process measures related to intervention implementation, and primary caregiver (PCG) satisfaction with the intervention. The full intervention was completed by 79% of PCGs, but only 17% of other smoking caregivers. Nearly all (98%) PCGs were satisfied with the care study nurses provided and felt the program might be helpful to others. Despite challenges, this intervention was feasible and well received reaching caregivers who were not actively seeking treatment for smoking cessation or secondhand smoke reduction. Anticipating the strategies required to implement such an intervention may help promote participant engagement and retention to enhance the program’s ultimate success. PMID:22717938

  18. Radiation dose reduction in digital breast tomosynthesis (DBT) by means of deep-learning-based supervised image processing

    NASA Astrophysics Data System (ADS)

    Liu, Junchi; Zarshenas, Amin; Qadir, Ammar; Wei, Zheng; Yang, Limin; Fajardo, Laurie; Suzuki, Kenji

    2018-03-01

    To reduce cumulative radiation exposure and lifetime risks for radiation-induced cancer from breast cancer screening, we developed a deep-learning-based supervised image-processing technique called neural network convolution (NNC) for radiation dose reduction in DBT. NNC employed patched-based neural network regression in a convolutional manner to convert lower-dose (LD) to higher-dose (HD) tomosynthesis images. We trained our NNC with quarter-dose (25% of the standard dose: 12 mAs at 32 kVp) raw projection images and corresponding "teaching" higher-dose (HD) images (200% of the standard dose: 99 mAs at 32 kVp) of a breast cadaver phantom acquired with a DBT system (Selenia Dimensions, Hologic, CA). Once trained, NNC no longer requires HD images. It converts new LD images to images that look like HD images; thus the term "virtual" HD (VHD) images. We reconstructed tomosynthesis slices on a research DBT system. To determine a dose reduction rate, we acquired 4 studies of another test phantom at 4 different radiation doses (1.35, 2.7, 4.04, and 5.39 mGy entrance dose). Structural SIMilarity (SSIM) index was used to evaluate the image quality. For testing, we collected half-dose (50% of the standard dose: 32+/-14 mAs at 33+/-5 kVp) and full-dose (standard dose: 68+/-23 mAs at 33+/-5 kvp) images of 10 clinical cases with the DBT system at University of Iowa Hospitals and Clinics. NNC converted half-dose DBT images of 10 clinical cases to VHD DBT images that were equivalent to full dose DBT images. Our cadaver phantom experiment demonstrated 79% dose reduction.

  19. Seasonal variation in denitrification and dissimilatory nitrate reduction to ammonia process rates and corresponding key functional genes along an estuarine nitrate gradient

    PubMed Central

    Smith, Cindy J.; Dong, Liang F.; Wilson, John; Stott, Andrew; Osborn, A. Mark; Nedwell, David B.

    2015-01-01

    This research investigated spatial-temporal variation in benthic bacterial community structure, rates of denitrification and dissimilatory nitrate reduction to ammonium (DNRA) processes and abundances of corresponding genes and transcripts at three sites—the estuary-head, mid-estuary and the estuary mouth (EM) along the nitrate gradient of the Colne estuary over an annual cycle. Denitrification rates declined down the estuary, while DNRA rates were higher at the estuary head and middle than the EM. In four out of the six 2-monthly time-points, rates of DNRA were greater than denitrification at each site. Abundance of gene markers for nitrate-reduction (nitrate reductase narG and napA), denitrification (nitrite reductase nirS) and DNRA (DNRA nitrite reductase nrfA) declined along the estuary with significant relationships between denitrification and nirS abundance, and DNRA and nrfA abundance. Spatially, rates of denitrification, DNRA and corresponding functional gene abundances decreased along the estuary. However, temporal correlations between rate processes and functional gene and transcript abundances were not observed. PMID:26082763

  20. Elemental sulfur recovery process

    DOEpatents

    Flytzani-Stephanopoulos, M.; Zhicheng Hu.

    1993-09-07

    An improved catalytic reduction process for the direct recovery of elemental sulfur from various SO[sub 2]-containing industrial gas streams. The catalytic process provides combined high activity and selectivity for the reduction of SO[sub 2] to elemental sulfur product with carbon monoxide or other reducing gases. The reaction of sulfur dioxide and reducing gas takes place over certain catalyst formulations based on cerium oxide. The process is a single-stage, catalytic sulfur recovery process in conjunction with regenerators, such as those used in dry, regenerative flue gas desulfurization or other processes, involving direct reduction of the SO[sub 2] in the regenerator off gas stream to elemental sulfur in the presence of a catalyst. 4 figures.

  1. Elemental sulfur recovery process

    DOEpatents

    Flytzani-Stephanopoulos, Maria; Hu, Zhicheng

    1993-01-01

    An improved catalytic reduction process for the direct recovery of elemental sulfur from various SO.sub.2 -containing industrial gas streams. The catalytic process provides combined high activity and selectivity for the reduction of SO.sub.2 to elemental sulfur product with carbon monoxide or other reducing gases. The reaction of sulfur dioxide and reducing gas takes place over certain catalyst formulations based on cerium oxide. The process is a single-stage, catalytic sulfur recovery process in conjunction with regenerators, such as those used in dry, regenerative flue gas desulfurization or other processes, involving direct reduction of the SO.sub.2 in the regenerator off gas stream to elemental sulfur in the presence of a catalyst.

  2. A New Technique for Preparation of High-Grade Titanium Slag from Titanomagnetite Concentrate by Reduction-Melting-Magnetic Separation Processing

    NASA Astrophysics Data System (ADS)

    Lv, Chao; Yang, Kun; Wen, Shu-ming; Bai, Shao-jun; Feng, Qi-cheng

    2017-10-01

    This paper proposes a new technique for preparation of high-grade titanium slag from Panzhihua vanadium titanomagnetite concentrate by reduction-melting-magnetic separation processing. Chemical analysis, x-ray diffraction, and scanning electron microscopy in conjunction with energy-dispersive spectroscopy were used to characterize the samples. The effective separation of iron and titanium slag could be realized by melting metallized pellets at 1550°C for 60 min with the addition of 1% CaO (basicity of 1.1) and 2% graphite powder. The small iron particles embedded in the slag could be removed by fine grinding and magnetic separation process. The grade of TiO2 in the obtained high-grade titanium slag reached 60.68% and the total recovery of TiO2 was 91.25%, which could be directly applied for producing titanium white by the sulfuric acid process. This technique provides an alternative method to use vanadium titanomagnetite concentrate of the Panzhihua area in China.

  3. Defining Constellation Suit Helmet Field of View Requirements Employing a Mission Segment Based Reduction Process

    NASA Technical Reports Server (NTRS)

    McFarland, Shane M.

    2008-01-01

    Field of view has always been a design feature paramount to helmet design, and in particular space suit design, where the helmet must provide an adequate field of view for a large range of activities, environments, and body positions. For Project Constellation, a slightly different approach to helmet requirement maturation was utilized; one that was less a direct function of body position and suit pressure and more a function of the mission segment in which the field of view is required. Through taxonimization of various parameters that affect suited FOV, as well as consideration for possible nominal and contingency operations during that mission segment, a reduction process was able to condense the large number of possible outcomes to only six unique field of view angle requirements that still captured all necessary variables without sacrificing fidelity. The specific field of view angles were defined by considering mission segment activities, historical performance of other suits, comparison between similar requirements (pressure visor up versus down, etc.), estimated requirements from other teams for field of view (Orion, Altair, EVA), previous field of view tests, medical data for shirtsleeve field of view performance, and mapping of visual field data to generate 45degree off-axis field of view requirements. Full resolution of several specific field of view angle requirements warranted further work, which consisted of low and medium fidelity field of view testing in the rear entry ISuit and DO27 helmet prototype. This paper serves to document this reduction progress and followup testing employed to write the Constellation requirements for helmet field of view.

  4. Post-processing of metal matrix composites by friction stir processing

    NASA Astrophysics Data System (ADS)

    Sharma, Vipin; Singla, Yogesh; Gupta, Yashpal; Raghuwanshi, Jitendra

    2018-05-01

    In metal matrix composites non-uniform distribution of reinforcement particles resulted in adverse affect on the mechanical properties. It is of great interest to explore post-processing techniques that can eliminate particle distribution heterogeneity. Friction stir processing is a relatively newer technique used for post-processing of metal matrix composites to improve homogeneity in particles distribution. In friction stir processing, synergistic effect of stirring, extrusion and forging resulted in refinement of grains, reduction of reinforcement particles size, uniformity in particles distribution, reduction in microstructural heterogeneity and elimination of defects.

  5. Reduction in Force. School Management Advisor, Issue 24.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Instruction, Raleigh.

    This document examines the legal requirements for the reduction in force (RIF) of North Carolina Department of Public Instruction employees, with a focus on certified (instructional) staff. A question-and-answer section discusses areas of concern to administrators about the reduction-in-force process. North Carolina State law relating to the RIF…

  6. Enantioselective reductive transformation of climbazole: A concept towards quantitative biodegradation assessment in anaerobic biological treatment processes.

    PubMed

    Brienza, Monica; Chiron, Serge

    2017-06-01

    An efficient chiral method-based using liquid chromatography-high resolution-mass spectrometry analytical method has been validated for the determination of climbazole (CBZ) enantiomers in wastewater and sludge with quantification limits below the 1 ng/L and 2 ng/g range, respectively. On the basis of this newly developed analytical method, the stereochemistry of CBZ was investigated over time in sludge biotic and sterile batch experiments under anoxic dark and light conditions and during wastewater biological treatment by subsurface flow constructed wetlands. CBZ stereoselective degradation was exclusively observed under biotic conditions, confirming the specificity of enantiomeric fraction variations to biodegradation processes. Abiotic CBZ enantiomerization was insignificant at circumneutral pH and CBZ was always biotransformed into CBZ-alcohol due to the specific and enantioselective reduction of the ketone function of CBZ into a secondary alcohol function. This transformation was almost quantitative and biodegradation gave good first order kinetic fit for both enantiomers. The possibility to apply the Rayleigh equation to enantioselective CBZ biodegradation processes was investigated. The results of enantiomeric enrichment allowed for a quantitative assessment of in situ biodegradation processes due to a good fit (R 2  > 0.96) of the anoxic/anaerobic CBZ biodegradation to the Rayleigh dependency in all the biotic microcosms and was also applied in subsurface flow constructed wetlands. This work extended the concept of applying the Rayleigh equation towards quantitative biodegradation assessment of organic contaminants to enantioselective processes operating under anoxic/anaerobic conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Improved HCP Reduction Using a New, All-Synthetic Depth Filtration Media Within an Antibody Purification Process.

    PubMed

    Nguyen, Hoang C; Langland, Amie L; Amara, John P; Dullen, Michael; Kahn, David S; Costanzo, Joseph A

    2018-04-30

    Biologic manufacturing processes typically employ clarification technologies like depth filtration to remove insoluble and soluble impurities. Conventional depth filtration media used in these processes contain naturally-derived components like diatomaceous earth and cellulose. These components may introduce performance variability and contribute extractable/leachable components like beta-glucans that could interfere with limulus amebocyte lysate endotoxin assays. Recently a novel, all-synthetic depth filtration media is developed (Millistak+ ® HC Pro X0SP) that may improve process consistency, efficiency, and drug substance product quality by reducing soluble process impurities. This new media is evaluated against commercially available benchmark filters containing naturally-derived components (Millistak+ ® HC X0HC and B1HC). Using model proteins, the synthetic media demonstrates increased binding capacity of positively charged proteins (72-126 mg g -1 media) compared to conventional media (0.3-8.6 mg g -1 media); and similar values for negatively charged species (1.3-5.6 mg g -1 media). Several CHO-derived monoclonal antibodies (mAbs) or mAb-like molecules are also evaluated. The X0SP filtration performance behaves similarly to benchmarks, and exhibits improved HCP reduction (at least 50% in 55% of cases tested). X0SP filtrates contained increased silicon extractables relative to benchmarks, but these were readily removed downstream. Finally, the X0SP devices demonstrates suitable lot-to-lot robustness when specific media components are altered intentionally to manufacturing specification limits. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Reduction of Thoroughbred racing fatalities at New York Racing Association racetracks using a multi-disciplinary mortality review process.

    PubMed

    Palmer, Scott E; McDonough, Sean P; Mohammed, Hussni O

    2017-07-01

    Between January 1, 2013 and December 31, 2015, findings of a New York State Gaming Commission-Cornell University postmortem examination program were utilized in a multi-disciplinary mortality review process to review 129 racing fatalities at Thoroughbred racetracks operated by the New York Racing Association (NYRA). Musculoskeletal fractures comprised 79% of the fatalities; cardiopulmonary conditions accounted for 12% of the fatalities. Other causes of death included gastrointestinal (3%), respiratory (5%), and central nervous system (2%) conditions. Fetlock failure represented 50% of the musculoskeletal fatalities. The general distribution of these findings was very similar to that reported by the California Animal Health and Food Safety Laboratory System during the same period. These findings, used in conjunction with a comprehensive mortality review process and regulatory reform, have contributed to a significant reduction of the incidence of Thoroughbred racing fatalities at NYRA racetracks during the period of this review.

  9. Effective dimension reduction for sparse functional data

    PubMed Central

    YAO, F.; LEI, E.; WU, Y.

    2015-01-01

    Summary We propose a method of effective dimension reduction for functional data, emphasizing the sparse design where one observes only a few noisy and irregular measurements for some or all of the subjects. The proposed method borrows strength across the entire sample and provides a way to characterize the effective dimension reduction space, via functional cumulative slicing. Our theoretical study reveals a bias-variance trade-off associated with the regularizing truncation and decaying structures of the predictor process and the effective dimension reduction space. A simulation study and an application illustrate the superior finite-sample performance of the method. PMID:26566293

  10. An Interactive Procedure to Preserve the Desired Edges during the Image Processing of Noise Reduction

    NASA Astrophysics Data System (ADS)

    Hsu, Chih-Yu; Huang, Hsuan-Yu; Lee, Lin-Tsang

    2010-12-01

    The paper propose a new procedure including four stages in order to preserve the desired edges during the image processing of noise reduction. A denoised image can be obtained from a noisy image at the first stage of the procedure. At the second stage, an edge map can be obtained by the Canny edge detector to find the edges of the object contours. Manual modification of an edge map at the third stage is optional to capture all the desired edges of the object contours. At the final stage, a new method called Edge Preserved Inhomogeneous Diffusion Equation (EPIDE) is used to smooth the noisy images or the previously denoised image at the first stage for achieving the edge preservation. The Optical Character Recognition (OCR) results in the experiments show that the proposed procedure has the best recognition result because of the capability of edge preservation.

  11. REDUCTION OF ARSENIC WASTES IN THE SEMICONDUCTOR INDUSTRY

    EPA Science Inventory

    The research described in this report was aimed at initiating and developing processes and process modifications that could be incorporated into semiconductor manufacturing operations to accomplish pollution prevention, especially to accomplish significant reduction in the quanti...

  12. Electro-oxidation of methanol and ethanol using PtRu/C, PtSn/C and PtSnRu/C electrocatalysts prepared by an alcohol-reduction process

    NASA Astrophysics Data System (ADS)

    Neto, Almir Oliveira; Dias, Ricardo R.; Tusi, Marcelo M.; Linardi, Marcelo; Spinacé, Estevam V.

    PtRu/C, PtSn/C and PtSnRu/C electrocatalysts were prepared by the alcohol reduction process using ethylene glycol as the solvent and reduction agent and Vulcan Carbon XC72 as the support. The electrocatalysts were characterized by EDX, XRD and cyclic voltammetry. The electrochemical oxidation of methanol and ethanol were studied by chronoamperometry using a thin porous coating technique. The PtSn/C electrocatalyst prepared by this methodology showed superior performance compared to the PtRu/C and PtSnRu/C electrocatalysts for methanol and ethanol oxidation at room temperature.

  13. Reduction of excess sludge production using mechanical disintegration devices.

    PubMed

    Strünkmann, G W; Müller, J A; Albert, F; Schwedes, J

    2006-01-01

    The usability of mechanical disintegration techniques for the reduction of excess sludge production in the activated sludge process was investigated. Using three different disintegration devices (ultrasonic homogeniser, stirred media mill, high pressure homogeniser) and different operational parameters of the disintegration, the effect of mechanical disintegration on the excess sludge production and on the effluent quality was studied within a continuously operated, laboratory scale wastewater treatment system with pre-denitrification. Depending on the operational conditions and the disintegration device used, a reduction of excess sludge production of up to 70% was achieved. A combination of mechanical disintegration with a membrane bioreactor process with high sludge age is more energy effective concerning reduction of sludge production than with a conventional activated sludge process at lower sludge ages. Depending on the disintegration parameters, the disintegration has no, or only minor, negative effect on the soluble effluent COD and on the COD-removal capacity of the activated sludge process. Nitrogen-removal was slightly deteriorated by the disintegration, whereas the system used was not optimised for nitrogen removal before disintegration was implemented.

  14. PCDD/PCDF reduction by the co-combustion process.

    PubMed

    Lee, Vinci K C; Cheung, Wai-Hung; McKay, Gordon

    2008-01-01

    A novel process, termed the co-combustion process, has been developed and designed to utilise the thermal treatment of municipal solid waste (MSW) in cement clinker production and reduce PCDD/PCDF emissions. To test the conceptual design; detailed engineering design of the process and equipment was performed and a pilot plant was constructed to treat up to 40 tonnes MSW per day. The novel process features included several units external to the main traditional cement rotary kiln: an external calcinations unit in which the hot gas calcined the limestone thus making significant energy savings for this chemical reaction; the lime generated was used in a second chamber to act as a giant acid gas scrubber to remove SOx and particularly HCl (a source of chloride); an external rotary kiln and secondary combustion unit capable of producing a hot gas at 1200 degrees C; a gas cooler to simulate a boiler turbogenerator set for electricity generation; the incorporation of some of the bottom ash, calcined lime and dust collector solids into the cement clinker. A PCDD/PCDF inventory has been completed for the entire process and measured PCDD/PCDF emissions were 0.001 ng I-TEQ/Nm(3) on average which is 1% of the best practical means [Hong Kong Environmental Protection Department, 2001. A guidance note on the best practicable means for incinerators (municipal waste incineration), BPM12/1] MSW incineration emission limit values.

  15. Overview of reductants utilized in nuclear fuel reprocessing/recycling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Patricia Paviet-Hartmann; Catherine Riddle; Keri Campbell

    2013-10-01

    Most of the aqueous processes developed, or under consideration worldwide for the recycling of used nuclear fuel (UNF) utilize the oxido-reduction properties of actinides to separate them from other radionuclides. Generally, after acid dissolution of the UNF, (essentially in nitric acid solution), actinides are separated from the raffinate by liquid-liquid extraction using specific solvents, associated along the process, with a particular reductant that will allow the separation to occur. For example, the industrial PUREX process utilizes hydroxylamine as a plutonium reductant. Hydroxylamine has numerous advantages: not only does it have the proper attributes to reduce Pu(IV) to Pu(III), but itmore » is also a non-metallic chemical that is readily decomposed to innocuous products by heating. However, it has been observed that the presence of high nitric acid concentrations or impurities (such as metal ions) in hydroxylamine solutions increase the likelihood of the initiation of an autocatalytic reaction. Recently there has been some interest in the application of simple hydrophilic hydroxamic ligands such as acetohydroxamic acid (AHA) for the stripping of tetravalent actinides in the UREX process flowsheet. This approach is based on the high coordinating ability of hydroxamic acids with tetravalent actinides (Np and Pu) compared with hexavalent uranium. Thus, the use of AHA offers a route for controlling neptunium and plutonium in the UREX process by complexant based stripping of Np(IV) and Pu(IV) from the TBP solvent phase, while U(VI) ions are not affected by AHA and remain solvated in the TBP phase. In the European GANEX process, AHA is also used to form hydrophilic complexes with actinides and strip them from the organic phase into nitric acid. However, AHA does not decompose completely when treated with nitric acid and hampers nitric acid recycling. In lieu of using AHA in the UREX + process, formohydroxamic acid (FHA), although not commercially available

  16. Microbial Manganese and Sulfate Reduction in Black Sea Shelf Sediments

    PubMed Central

    Thamdrup, Bo; Rosselló-Mora, Ramón; Amann, Rudolf

    2000-01-01

    The microbial ecology of anaerobic carbon oxidation processes was investigated in Black Sea shelf sediments from mid-shelf with well-oxygenated bottom water to the oxic-anoxic chemocline at the shelf-break. At all stations, organic carbon (Corg) oxidation rates were rapidly attenuated with depth in anoxically incubated sediment. Dissimilatory Mn reduction was the most important terminal electron-accepting process in the active surface layer to a depth of ∼1 cm, while SO42− reduction accounted for the entire Corg oxidation below. Manganese reduction was supported by moderately high Mn oxide concentrations. A contribution from microbial Fe reduction could not be discerned, and the process was not stimulated by addition of ferrihydrite. Manganese reduction resulted in carbonate precipitation, which complicated the quantification of Corg oxidation rates. The relative contribution of Mn reduction to Corg oxidation in the anaerobic incubations was 25 to 73% at the stations with oxic bottom water. In situ, where Mn reduction must compete with oxygen respiration, the contribution of the process will vary in response to fluctuations in bottom water oxygen concentrations. Total bacterial numbers as well as the detection frequency of bacteria with fluorescent in situ hybridization scaled to the mineralization rates. Most-probable-number enumerations yielded up to 105 cells of acetate-oxidizing Mn-reducing bacteria (MnRB) cm−3, while counts of Fe reducers were <102 cm−3. At two stations, organisms affiliated with Arcobacter were the only types identified from 16S rRNA clone libraries from the highest positive MPN dilutions for MnRB. At the third station, a clone type affiliated with Pelobacter was also observed. Our results delineate a niche for dissimilatory Mn-reducing bacteria in sediments with Mn oxide concentrations greater than ∼10 μmol cm−3 and indicate that bacteria that are specialized in Mn reduction, rather than known Mn and Fe reducers, are important

  17. Combinative Particle Size Reduction Technologies for the Production of Drug Nanocrystals

    PubMed Central

    Salazar, Jaime; Müller, Rainer H.; Möschwitzer, Jan P.

    2014-01-01

    Nanosizing is a suitable method to enhance the dissolution rate and therefore the bioavailability of poorly soluble drugs. The success of the particle size reduction processes depends on critical factors such as the employed technology, equipment, and drug physicochemical properties. High pressure homogenization and wet bead milling are standard comminution techniques that have been already employed to successfully formulate poorly soluble drugs and bring them to market. However, these techniques have limitations in their particle size reduction performance, such as long production times and the necessity of employing a micronized drug as the starting material. This review article discusses the development of combinative methods, such as the NANOEDGE, H 96, H 69, H 42, and CT technologies. These processes were developed to improve the particle size reduction effectiveness of the standard techniques. These novel technologies can combine bottom-up and/or top-down techniques in a two-step process. The combinative processes lead in general to improved particle size reduction effectiveness. Faster production of drug nanocrystals and smaller final mean particle sizes are among the main advantages. The combinative particle size reduction technologies are very useful formulation tools, and they will continue acquiring importance for the production of drug nanocrystals. PMID:26556191

  18. Reduction of verotoxigenic Escherichia coli in production of fermented sausages.

    PubMed

    Holck, Askild L; Axelsson, Lars; Rode, Tone Mari; Høy, Martin; Måge, Ingrid; Alvseike, Ole; L'abée-Lund, Trine M; Omer, Mohamed K; Granum, Per Einar; Heir, Even

    2011-11-01

    After a number of foodborne outbreaks of verotoxigenic Escherichia coli involving fermented sausages, some countries have imposed regulations on sausage production. For example, the US Food Safety and Inspection Service requires a 5 log(10) reduction of E. coli in fermented products. Such regulations have led to a number of studies on the inactivation of E. coli in fermented sausages by changing processing and post-processing conditions. Several factors influence the survival of E. coli such as pre-treatment of the meat, amount of NaCl, nitrite and lactic acid, water activity, pH, choice of starter cultures and addition of antimicrobial compounds. Also process variables like fermentation temperature and storage time play important roles. Though a large variety of different production processes of sausages exist, generally the reduction of E. coli caused by production is in the range 1-2 log(10). In many cases this may not be enough to ensure microbial food safety. By optimising ingredients and process parameters it is possible to increase E. coli reduction to some extent, but in some cases still other post process treatments may be required. Such treatments may be storage at ambient temperatures, specific heat treatments, high pressure processing or irradiation. HACCP analyses have identified the quality of the raw materials, low temperature in the batter when preparing the sausages and a rapid pH drop during fermentation as critical control points in sausage production. This review summarises the literature on the reduction verotoxigenic E. coli in production of fermented sausages. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Driving reduction and cessation : transitioning to not driving.

    DOT National Transportation Integrated Search

    2009-09-01

    This project examined the process of driving reduction and cessation from the perspective of older adults (current and former drivers) and adult children. The objectives were to identify common markers of the process of driving cessation and to gain ...

  20. Chromium Isotope Behaviour During Aerobic Microbial Reduction Activities

    NASA Astrophysics Data System (ADS)

    Zhang, Q.; Amor, K.; Porcelli, D.; Thompson, I.

    2014-12-01

    Microbial activity is a very important, and possibly even the dominant, reduction mechanism for many metals in natural water systems. Isotope fractionations during microbial metal reduction can reflect one major mechanism in metal cycling in the environment, and isotopic signatures can be used to identify and quantify reduction processes during biogeochemical cycling in the present environment as well as in the past. There are many Cr (VI)-reducing bacteria that have been discovered and isolated from the environment, and Cr isotopes were found to be fractionated during microbial reduction processes. In this study, Cr reduction experiments have been undertaken to determine the conditions under which Cr is reduced and the corresponding isotope signals that are generated. The experiments have been done with a facultative bacteria Pseudomonas fluorescens LB 300, and several parameters that have potential impact on reduction mechanisms have been investigated. Electron donors are important for bacteria growth and metabolism. One factor that can control the rate of Cr reduction is the nature of the electron donor. The results show that using citrate as an electron donor can stimulate bacteria reduction activity to a large extent; the reduction rate is much higher (15.10 mgˑL-1hour-1) compared with experiments using glucose (6.65 mgˑL-1ˑhour-1), acetate (4.88 mgˑL-1hour-1) or propionate (4.85 mgˑL-1hour-1) as electron donors. Groups with higher electron donor concentrations have higher reduction rates. Chromium is toxic, and when increasing Cr concentrations in the medium, the bacteria reduction rate is also higher, which reflects bacteria adapting to the toxic environment. In the natural environment, under different pH conditions, bacteria may metabolise in different ways. In our experiments with pH, bacteria performed better in reducing Cr (VI) when pH = 8, and there are no significant differences between groups with pH = 4 or pH = 6. To investigate this further, Cr

  1. In situ X-ray diffraction study of reduction processes of Fe{sub 3}O{sub 4}- and Fe{sub 1-x}O-based ammonia-synthesis catalysts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zheng Yifan, E-mail: zhengyifan@zjut.edu.c; Catalysis Institute, Zhejiang University of Technology, Hangzhou 310014; Liu Huazhang

    2009-09-15

    The temperature-programmed reduction process of two types of industrial ammonia-synthesis catalysts, A110 and ZA-5, which are, respectively, based on Fe{sub 3}O{sub 4} and Fe{sub 1-x}O precursors, were studied by in situ X-ray power diffraction (XRD). It has been found that the ZA-5 has lower reduction temperature and faster reduction rate, and its active phase alpha-Fe possesses a higher value of lattice microstrain than A110. The simulation based on Rietveld refinement has also shown that the shape of alpha-Fe grain of ZA-5 has a mixed shape of cube and sphere with more exposing (111) and (211) planes, while that of A110more » looks like a concave cube with more exposing (110) planes. Based on the results obtained, a growth model of alpha-Fe during the reduction of Fe{sub 3}O{sub 4}- and Fe{sub 1-x}O-based ammonia-synthesis catalysts is proposed, and the origins for the activity difference has been also discussed. - Graphical Abstract: A proposed growth model of active phase alpha-Fe during reduction. Due to H{sub 2} diffusing easily into the pores, reduction starts on outside and inside surface simultaneously to form 'microcrystalline film', and the particles shrink during reduction which results in breaking of the aggregated oxide particle.« less

  2. Drag reduction strategies

    NASA Technical Reports Server (NTRS)

    Hill, D. Christopher

    1994-01-01

    previously a description was given of an active control scheme using wall transpiration that leads to a 15% reduction in surface skin friction beneath a turbulent boundary layer, according to direct numerical simulation. In this research brief further details of that scheme and its variants are given together with some suggestions as to how sensor/actuator arrays could be configured to reduce surface drag. The research which is summarized here was performed during the first half of 1994. This research is motivated by the need to understand better how the dynamics of near-wall turbulent flow can be modified so that skin friction is reduced. The reduction of turbulent skin friction is highly desirable in many engineering applications. Experiments and direct numerical simulations have led to an increased understanding of the cycle of turbulence production and transport in the boundary layer and raised awareness of the possibility of disrupting the process with a subsequent reduction in turbulent skin friction. The implementation of active feedback control in a computational setting is a viable approach for the investigation of the modifications to the flow physics that can be achieved. Bewley et al. and Hill describe how ideas from optimal control theory are employed to give 'sub-optimal' drag reduction schemes. The objectives of the work reported here is to investigate in greater detail the assumptions implicit within such schemes and their limitations. It is also our objective to describe how an array of sensors and actuators could be arranged and interconnected to form a 'smart' surface which has low skin friction.

  3. Interactions between Biological and Abiotic Pathways in the Reduction of Chlorinated Solvents

    EPA Science Inventory

    While biologically mediated reductive dechlorination continues to be a significant focus of chlorinated solvent remediation, there has been an increased interest in abiotic reductive processes for the remediation of chlorinated solvents. In situ chemical reduction (ISCR) uses zer...

  4. Green reduction of graphene oxide by ascorbic acid

    NASA Astrophysics Data System (ADS)

    Khosroshahi, Zahra; Kharaziha, Mahshid; Karimzadeh, Fathallah; Allafchian, Alireza

    2018-01-01

    Graphene, a single layer of sp2-hybridized carbon atoms in a hexagonal (two-dimensional honey-comb) lattice, has attracted strong scientific and technological interest due to its novel and excellent optical, chemical, electrical, mechanical and thermal properties. The solution-processable chemical reduction of Graphene oxide (GO is considered as the most favorable method regarding mass production of graphene. Generally, the reduction of GO is carried out by chemical approaches using different reductants such as hydrazine and sodium borohydride. These components are corrosive, combustible and highly toxic which may be dangerous for personnel health and the environment. Hence, these reducing agents are not promising choice for reducing of graphene oxide (GO). As a consequence, it is necessary for further development and optimization of eco-friendly, natural reducing agent for clean and effective reduction of GO. Ascorbic acid, an eco-friendly and natural reducing agents, having a mild reductive ability and nontoxic property. So, the aim of this research was to green synthesis of GO with ascorbic acid. For this purpose, the required amount of NaOH and ascorbic acid were added to GO solution (0.5 mg/ml) and were heated at 95 °C for 1 hour. According to the X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and electrochemical results, GO were reduced with ascorbic acid like hydrazine with better electrochemical properties and ascorbic acid is an ideal substitute for hydrazine in the reduction of graphene oxide process.

  5. Speckle reduction process based on digital filtering and wavelet compounding in optical coherence tomography for dermatology

    NASA Astrophysics Data System (ADS)

    Gómez Valverde, Juan J.; Ortuño, Juan E.; Guerra, Pedro; Hermann, Boris; Zabihian, Behrooz; Rubio-Guivernau, José L.; Santos, Andrés.; Drexler, Wolfgang; Ledesma-Carbayo, Maria J.

    2015-07-01

    Optical Coherence Tomography (OCT) has shown a great potential as a complementary imaging tool in the diagnosis of skin diseases. Speckle noise is the most prominent artifact present in OCT images and could limit the interpretation and detection capabilities. In this work we propose a new speckle reduction process and compare it with various denoising filters with high edge-preserving potential, using several sets of dermatological OCT B-scans. To validate the performance we used a custom-designed spectral domain OCT and two different data set groups. The first group consisted in five datasets of a single B-scan captured N times (with N<20), the second were five 3D volumes of 25 Bscans. As quality metrics we used signal to noise (SNR), contrast to noise (CNR) and equivalent number of looks (ENL) ratios. Our results show that a process based on a combination of a 2D enhanced sigma digital filter and a wavelet compounding method achieves the best results in terms of the improvement of the quality metrics. In the first group of individual B-scans we achieved improvements in SNR, CNR and ENL of 16.87 dB, 2.19 and 328 respectively; for the 3D volume datasets the improvements were 15.65 dB, 3.44 and 1148. Our results suggest that the proposed enhancement process may significantly reduce speckle, increasing SNR, CNR and ENL and reducing the number of extra acquisitions of the same frame.

  6. A Bayesian nonparametric approach to dynamical noise reduction

    NASA Astrophysics Data System (ADS)

    Kaloudis, Konstantinos; Hatjispyros, Spyridon J.

    2018-06-01

    We propose a Bayesian nonparametric approach for the noise reduction of a given chaotic time series contaminated by dynamical noise, based on Markov Chain Monte Carlo methods. The underlying unknown noise process (possibly) exhibits heavy tailed behavior. We introduce the Dynamic Noise Reduction Replicator model with which we reconstruct the unknown dynamic equations and in parallel we replicate the dynamics under reduced noise level dynamical perturbations. The dynamic noise reduction procedure is demonstrated specifically in the case of polynomial maps. Simulations based on synthetic time series are presented.

  7. trans-[Pt(BCat')Me(PCy3)2]: an experimental case study of reductive elimination processes in Pt-Boryls through associative mechanisms.

    PubMed

    Braunschweig, Holger; Bertermann, Rüdiger; Brenner, Peter; Burzler, Michael; Dewhurst, Rian D; Radacki, Krzysztof; Seeler, Fabian

    2011-10-10

    A stable trans-(alkyl)(boryl) platinum complex trans-[Pt(BCat')Me(PCy(3))(2)] (Cat'=Cat-4-tBu; Cy=cyclohexyl=C(6)H(11)) was synthesised by salt metathesis reaction of trans-[Pt(BCat')Br(PCy(3))(2)] with LiMe and was fully characterised. Investigation of the reactivity of the title compound showed complete reductive elimination of Cat'BMe at 80 °C within four weeks. This process may be accelerated by the addition of a variety of alkynes, thereby leading to the formation of the corresponding η(2) -alkyne platinum complexes, of which [Pt(η(2)-MeCCMe)(PCy(3))(2)] was characterised by X-ray crystallography. Conversion of the trans-configured title compound to a cis derivative remained unsuccessful due to an instantaneous reductive elimination process during the reaction with chelating phosphines. Treatment of trans-[Pt(BCat')Me(PCy(3))(2)] with Cat(2)B(2) led to the formation of CatBMe and Cat'BMe. In the course of further investigations into this reaction, indications for two indistinguishable reaction mechanisms were found: 1) associative formation of a six-coordinate platinum centre prior to reductive elimination and 2) σ-bond metathesis of B-B and C-Pt bonds. Mechanism 1 provides a straightforward explanation for the formation of both methylboranes. Scrambling of diboranes(4) Cat(2)B(2) and Cat'(2)B(2) in the presence of [Pt(PCy(3))(2)], fully reductive elimination of CatBMe or Cat'BMe from trans-[Pt(BCat')Me(PCy(3))(2)] in the presence of sub-stoichiometric amounts of Cat(2)B(2), and evidence for the reversibility of the oxidative addition of Cat(2)B(2) to [Pt(PCy(3))(2)] all support mechanism 2, which consists of sequential equilibria reactions. Furthermore, the solid-state molecular structure of cis-[Pt(BCat)(2)(PCy(3))(2)] and cis-[Pt(BCat')(2)(PCy(3))(2)] were investigated. The remarkably short B-B separations in both bis(boryl) complexes suggest that the two boryl ligands in each case are more loosely bound to the Pt(II) centre than in related bis

  8. Materials and Process Design for High-Temperature Carburizing: Integrating Processing and Performance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    D. Apelian

    2007-07-23

    The objective of the project is to develop an integrated process for fast, high-temperature carburizing. The new process results in an order of magnitude reduction in cycle time compared to conventional carburizing and represents significant energy savings in addition to a corresponding reduction of scrap associated with distortion free carburizing steels.

  9. Physical pretreatment – woody biomass size reduction – for forest biorefinery

    Treesearch

    J.Y. Zhu

    2011-01-01

    Physical pretreatment of woody biomass or wood size reduction is a prerequisite step for further chemical or biochemical processing in forest biorefinery. However, wood size reduction is very energy intensive which differentiates woody biomass from herbaceous biomass for biorefinery. This chapter discusses several critical issues related to wood size reduction: (1)...

  10. Energy Saving Melting and Revert Reduction Technology: Improved Die Casting Process to Preserve the Life of the Inserts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    David Schwam, PI; Xuejun Zhu, Sr. Research Associate

    2012-09-30

    with die lubricants and technical support. Experiments conducted with these lubricants demonstrated good protection of the substrate steel. Graphite and boron nitride used as benchmarks are capable of completely eliminating soldering and washout. However, because of cost and environmental considerations these materials are not widely used in industry. The best water-based die lubricants evaluated in this program were capable of providing similar protection from soldering and washout. In addition to improved part quality and higher production rates, improving die casting processes to preserve the life of the inserts will result in energy savings and a reduction in environmental wastes. Improving die life by means of optimized cooling line placement, baffles and bubblers in the die will allow for reduced die temperatures during processing, saving energy associated with production. The utilization of optimized die lubricants will also reduce heat requirements in addition to reducing waste associated with soldering and washout. This new technology was predicted to result in an average energy savings of 1.1 trillion BTU's/year over a 10 year period. Current (2012) annual energy saving estimates, based on commercial introduction in 2010, a market penetration of 70% by 2020 is 1.26 trillion BTU's/year. Along with these energy savings, reduction of scrap and improvement in casting yield will result in a reduction of the environmental emissions associated with the melting and pouring of the metal which will be saved as a result of this technology. The average annual estimate of CO2 reduction per year through 2020 is 0.025 Million Metric Tons of Carbon Equivalent (MM TCE).« less

  11. Manganese inhibition of microbial iron reduction in anaerobic sediments

    USGS Publications Warehouse

    Lovley, D.R.; Phillips, E.J.P.

    1988-01-01

    Potential mechanisms for the lack of Fe(II) accumulation in Mn(IV)-containing anaerobic sediments were investigated. The addition of Mn(IV) to sediments in which Fe(II) reduction was the terminal electron-accepting process removed all the pore-water Fe(II), completely inhibited net Fe(III) reduction, and stimulated Mn(IV) reduction. Results demonstrate that preferential reduction of Mn(IV) by FE(III)-reducing bacteria cannot completely explain the lack of Fe(II) accumulation in anaerobic, Mn(IV)-containing sediments, and indicate that Mn(IV) oxidation of Fe(II) is the mechanism that ultimately prevents Fe(II) accumulation. -Authors

  12. Stability of mycotoxins during food processing.

    PubMed

    Bullerman, Lloyd B; Bianchini, Andreia

    2007-10-20

    The mycotoxins that commonly occur in cereal grains and other products are not completely destroyed during food processing operations and can contaminate finished processed foods. The mycotoxins most commonly associated with cereal grains are aflatoxins, ochratoxin A, fumonisins, deoxynivalenol and zearalenone. The various food processes that may have effects on mycotoxins include sorting, trimming, cleaning, milling, brewing, cooking, baking, frying, roasting, canning, flaking, alkaline cooking, nixtamalization, and extrusion. Most of the food processes have variable effects on mycotoxins, with those that utilize the highest temperatures having greatest effects. In general the processes reduce mycotoxin concentrations significantly, but do not eliminate them completely. However, roasting and extrusion processing show promise for lowering mycotoxin concentrations, though very high temperatures are needed to bring about much of a reduction in mycotoxin concentrations. Extrusion processing at temperatures greater than 150 degrees C are needed to give good reduction of zearalenone, moderate reduction of alfatoxins, variable to low reduction of deoxynivalenol and good reduction of fumonisins. The greatest reductions of fumonisins occur at extrusion temperatures of 160 degrees C or higher and in the presence of glucose. Extrusion of fumonisin contaminated corn grits with 10% added glucose resulted in 75-85% reduction in Fumonisin B(1) levels. Some fumonisin degredation products are formed during extrusion, including small amounts of hydrolyzed Fumonisin B(1) and N-(Carboxymethyl) - Fumonisin B(1) and somewhat higher amounts of N-(1-deoxy-d-fructos-1-yl) Fumonisin B(1) in extruded grits containing added glucose. Feeding trial toxicity tests in rats with extruded fumonisin contaminated corn grits show some reduction in toxicity of grits extruded with glucose.

  13. Conceptual design of a data reduction system

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A telemetry data processing system was defined of the Data Reduction. Data reduction activities in support of the developmental flights of the Space Shuttle were used as references against which requirements are assessed in general terms. A conceptual system design believed to offer significant throughput for the anticipated types of data reduction activities is presented. The design identifies the use of a large, intermediate data store as a key element in a complex of high speed, single purpose processors, each of which performs predesignated, repetitive operations on either raw or partially processed data. The recommended approach to implement the design concept is to adopt an established interface standard and rely heavily on mature or promising technologies which are considered main stream of the integrated circuit industry. The design system concept, is believed to be implementable without reliance on exotic devices and/or operational procedures. Numerical methods were employed to examine the feasibility of digital discrimination of FDM composite signals, and of eliminating line frequency noises in data measurements.

  14. An investigation of the reduction of carbon dioxide in a silent electric discharge

    NASA Technical Reports Server (NTRS)

    Luce, R. S.; Greenough, B. (Editor)

    1978-01-01

    The reduction of CO2 to O2 and CO in a silent electric discharge was studied. It was found that current alone (in the ionized plasma induced by the silent electric discharge) was reponsible for the CO2 reduction process. Voltage and frequency were important only in so far as they induced current in the plasma. Pressure and temperature were of minimum influence in the process. The large power consumption in the process was recognized as resulting from the low power factor of the reactor vessel which electrically behaved like a capacitor. The power factor was subsequently improved by adding an inductive element to make the reactor vessel capacitance part of a resonant circuit. It was found that the CO2 reduction process was most efficient in terms of power vs reduction rate when a voltage was employed that was only slightly higher than that needed to induce the plasma.

  15. An innovative sewage sludge reduction by using a combined mesophilic anaerobic and thermophilic aerobic process with thermal-alkaline treatment and sludge recirculation.

    PubMed

    Cho, Hyun Uk; Park, Sang Kyu; Ha, Jeong Hyub; Park, Jong Moon

    2013-11-15

    Lab-scale High Efficiency Digestion (HED) systems containing a Mesophilic Anaerobic Reactor (MAR), Thermophilic Aerobic Reactor (TAR), liquid/solid separation unit, and thermal-alkaline treatment were developed to evaluate the efficiencies of sludge reduction and methane production. The HED process was divided into three phases to examine the influence of sludge pretreatment and pretreated sludge recirculation using TCOD and VSS reduction, COD solubilization, and methane production. The VSS removal with a solid/liquid separation unit, sludge recirculation, and thermal-alkaline treatment drastically increased up to 95% compared to the feed concentration. In addition, the results of COD solubilization and VSS/TSS showed that the solubilization of cells and organic matters by the thermal-alkaline treatment was highly increased, which was also consistent with the SEM images. In particular, the methane production rate increased 24-fold when the feed sludge and recirculated sludge were pretreated together. Collectively, the HED experiments performed with sludge recirculation and thermal-alkaline treatment demonstrated that the HED systems can be successfully employed for highly efficient sewage sludge reduction and methane gas production. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Reduction of Iron-Oxide-Carbon Composites: Part III. Shrinkage of Composite Pellets during Reduction

    NASA Astrophysics Data System (ADS)

    Halder, S.; Fruehan, R. J.

    2008-12-01

    This article involves the evaluation of the volume change of iron-oxide-carbon composite pellets and its implications on reduction kinetics under conditions prevalent in a rotary hearth furnace (RHF) that were simulated in the laboratory. The pellets, in general, were found to shrink considerably during the reduction due to the loss of carbon and oxygen from the system, sintering of the iron-oxide, and formation of a molten slag phase at localized regions inside the pellets due to the presence of binder and coal/wood-charcoal ash at the reduction temperatures. One of the shortcomings of the RHF ironmaking process has been the inability to use multiple layers of composite pellets because of the impediment in heat transport to the lower layers of a multilayer bed. However, pellet shrinkage was found to have a strong effect on the reduction kinetics by virtue of enhancing the external heat transport to the lower layers. The volume change of the different kinds of composite pellets was studied as a function of reduction temperature and time. The estimation of the change in the amount of external heat transport with varying pellet sizes for a particular layer of a multilayer bed was obtained by conducting heat-transfer tests using inert low-carbon steel spheres. It was found that if the pellets of the top layer of the bed shrink by 30 pct, the external heat transfer to the second layer increases by nearly 6 times.

  17. Analog VLSI system for active drag reduction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gupta, B.; Goodman, R.; Jiang, F.

    1996-10-01

    In today`s cost-conscious air transportation industry, fuel costs are a substantial economic concern. Drag reduction is an important way to reduce costs. Even a 5% reduction in drag translates into estimated savings of millions of dollars in fuel costs. Drawing inspiration from the structure of shark skin, the authors are building a system to reduce drag along a surface. Our analog VLSI system interfaces with microfabricated, constant-temperature shear stress sensors. It detects regions of high shear stress and outputs a control signal to activate a microactuator. We are in the process of verifying the actual drag reduction by controlling microactuatorsmore » in wind tunnel experiments. We are encouraged that an approach similar to one that biology employs provides a very useful contribution to the problem of drag reduction. 9 refs., 21 figs.« less

  18. Kinetic study of nickel laterite reduction roasting by palm kernel shell charcoal

    NASA Astrophysics Data System (ADS)

    Sugiarto, E.; Putera, A. D. P.; Petrus, H. T. B. M.

    2017-05-01

    Demand to process nickel-bearing laterite ore increase as continuous depletion of high-grade nickel-bearing sulfide ore takes place. Due to its common nickel association with iron, processing nickel laterite ore into nickel pig iron (NPI) has been developed by some industries. However, to achieve satisfying nickel recoveries, the process needs massive high-grade metallurgical coke consumption. Concerning on the sustainability of coke supply and positive carbon emission, reduction of nickel laterite ore using biomass-based reductor was being studied.In this study, saprolitic nickel laterite ore was being reduced by palm kernel shell charcoal at several temperatures (800-1000 °C). Variation of biomass-laterite composition was also conducted to study the reduction mechanism. X-ray diffraction and gravimetry analysis were applied to justify the phenomenon and predict kinetic model of the reduction. Results of this study provide information that palm kernel shell charcoal has similar reducing result compared with the conventional method. Reduction, however, was carried out by carbon monoxide rather than solid carbon. Regarding kinetics, Ginstling-Brouhnstein kinetic model provides satisfying results to predict the reduction phenomenon.

  19. Automated Reduction of Data from Images and Holograms

    NASA Technical Reports Server (NTRS)

    Lee, G. (Editor); Trolinger, James D. (Editor); Yu, Y. H. (Editor)

    1987-01-01

    Laser techniques are widely used for the diagnostics of aerodynamic flow and particle fields. The storage capability of holograms has made this technique an even more powerful. Over 60 researchers in the field of holography, particle sizing and image processing convened to discuss these topics. The research program of ten government laboratories, several universities, industry and foreign countries were presented. A number of papers on holographic interferometry with applications to fluid mechanics were given. Several papers on combustion and particle sizing, speckle velocimetry and speckle interferometry were given. A session on image processing and automated fringe data reduction techniques and the type of facilities for fringe reduction was held.

  20. Dissolution and reduction of magnetite by bacteria.

    PubMed

    Kostka, J E; Nealson, K H

    1995-10-01

    Magnetite (Fe3O4) is an iron oxide of mixed oxidation state [Fe(II), Fe(III)] that contributes largely to geomagnetism and plays a significant role in diagenesis in marine and freshwater sediments. Magnetic data are the primary evidence for ocean floor spreading and accurate interpretation of the sedimentary magnetic record depends on an understanding of the conditions under which magnetite is stable. Though chemical reduction of magnetite by dissolved sulfide is well known, biological reduction has not been considered likely based upon thermodynamic considerations. This study shows that marine and freshwater strains of the bacterium Shewanella putrefaciens are capable of the rapid dissolution and reduction of magnetite, converting millimolar amounts to soluble Fe(II)in a few days at room temperature. Conditions under which magnetite reduction is optimal (pH 5-6, 22-37 degrees C) are consistent with an enzymatic process and not with simple chemical reduction. Magnetite reduction requires viable cells and cell contact, and it appears to be coupled to electron transport and growth. In a minimal medium with formate or lactate as the electron donor, more than 10 times the amount of magnetite was reduced over no carbon controls. These data suggest that magnetite reduction is coupled to carbon metabolism in S. putrefaciens. Bacterial reduction rates of magnetite are of the same order of magnitude as those estimated for reduction by sulfide. If such remobilization of magnetite occurs in nature, it could have a major impact on sediment magnetism and diagenesis.

  1. Dissolution and reduction of magnetite by bacteria

    NASA Technical Reports Server (NTRS)

    Kostka, J. E.; Nealson, K. H.

    1995-01-01

    Magnetite (Fe3O4) is an iron oxide of mixed oxidation state [Fe(II), Fe(III)] that contributes largely to geomagnetism and plays a significant role in diagenesis in marine and freshwater sediments. Magnetic data are the primary evidence for ocean floor spreading and accurate interpretation of the sedimentary magnetic record depends on an understanding of the conditions under which magnetite is stable. Though chemical reduction of magnetite by dissolved sulfide is well known, biological reduction has not been considered likely based upon thermodynamic considerations. This study shows that marine and freshwater strains of the bacterium Shewanella putrefaciens are capable of the rapid dissolution and reduction of magnetite, converting millimolar amounts to soluble Fe(II)in a few days at room temperature. Conditions under which magnetite reduction is optimal (pH 5-6, 22-37 degrees C) are consistent with an enzymatic process and not with simple chemical reduction. Magnetite reduction requires viable cells and cell contact, and it appears to be coupled to electron transport and growth. In a minimal medium with formate or lactate as the electron donor, more than 10 times the amount of magnetite was reduced over no carbon controls. These data suggest that magnetite reduction is coupled to carbon metabolism in S. putrefaciens. Bacterial reduction rates of magnetite are of the same order of magnitude as those estimated for reduction by sulfide. If such remobilization of magnetite occurs in nature, it could have a major impact on sediment magnetism and diagenesis.

  2. Reduction of antiproliferative capacities, cell-based antioxidant capacities and phytochemical contents of common beans and soybeans upon thermal processing.

    PubMed

    Xu, Baojun; Chang, Sam K C

    2011-12-01

    The effects of boiling and steaming processes on the antiproliferative and cellular antioxidant properties, as well as phytochemicals, of two types of common beans (pinto and black beans) and two types of soybeans (yellow and black) were investigated. All thermal-processing methods caused significant (p<0.05) decreases in total phenolic content (TPC), total saponin content (TSC) and phytic acid content (PAC) values in all bean types (except for TPC values in pressure-steamed yellow soybeans) as compared to those of the raw beans. All types of uncooked raw beans exhibited cellular antioxidant activities (CAA) in dose-dependent manners. Black soybeans exhibited the greatest CAA, followed by black beans, pinto beans and yellow soybeans. The CAA of cooked beans were generally diminished or eliminated by thermal processing. The hydrophilic extracts from raw pinto beans, black beans and black soybeans exhibited antiproliferation capacities against human gastric (AGS) and colorectal (SW480) cancer cells in dose-dependent manners. The raw yellow soybeans exhibited dose-dependent antiproliferation activities against the SW480 cells. Most of the cooked beans lost their antiproliferation capacities as observed in the raw beans. These results indicate that different processing methods may have various effects on phytochemical profiles and bioactivities. Overall, thermal processing caused a significant reduction of the health-promotion effects of beans. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Revisiting Training and Verification Process Implementation for Risk Reduction on New Missions at NASA Jet Propulsion Laboratory

    NASA Technical Reports Server (NTRS)

    Bryant, Larry W.; Fragoso, Ruth S.

    2007-01-01

    In 2003 we proposed an effort to develop a core program of standardized training and verification practices and standards against which the implementation of these practices could be measured. The purpose was to provide another means of risk reduction for deep space missions to preclude the likelihood of a repeat of the tragedies of the 1998 Mars missions. We identified six areas where the application of standards and standardization would benefit the overall readiness process for flight projects at JPL. These are Individual Training, Team Training, Interface and Procedure Development, Personnel Certification, Interface and procedure Verification, and Operations Readiness Testing. In this paper we will discuss the progress that has been made in the tasks of developing the proposed infrastructure in each of these areas. Specifically we will address the Position Training and Certification Standards that are now available for each operational position found on our Flight Operations Teams (FOT). We will also discuss the MGSS Baseline Flight Operations Team Training Plan which can be tailored for each new flight project at JPL. As these tasks have been progressing, the climate and emphasis for Training and for V and V at JPL has changed, and we have learned about the expansion, growth, and limitations in the roles of traditional positions at JPL such as the Project's Training Engineer, V and V Engineer, and Operations Engineer. The need to keep a tight rein on budgets has led to a merging and/or reduction in these positions which pose challenges to individual capacities and capabilities. We examine the evolution of these processes and the roles involved while taking a look at the impact or potential impact of our proposed training related infrastructure tasks. As we conclude our examination of the changes taking place for new flight projects, we see that the importance of proceeding with our proposed tasks and adapting them to the changing climate remains an important

  4. Uncertainty Reduction for Stochastic Processes on Complex Networks

    NASA Astrophysics Data System (ADS)

    Radicchi, Filippo; Castellano, Claudio

    2018-05-01

    Many real-world systems are characterized by stochastic dynamical rules where a complex network of interactions among individual elements probabilistically determines their state. Even with full knowledge of the network structure and of the stochastic rules, the ability to predict system configurations is generally characterized by a large uncertainty. Selecting a fraction of the nodes and observing their state may help to reduce the uncertainty about the unobserved nodes. However, choosing these points of observation in an optimal way is a highly nontrivial task, depending on the nature of the stochastic process and on the structure of the underlying interaction pattern. In this paper, we introduce a computationally efficient algorithm to determine quasioptimal solutions to the problem. The method leverages network sparsity to reduce computational complexity from exponential to almost quadratic, thus allowing the straightforward application of the method to mid-to-large-size systems. Although the method is exact only for equilibrium stochastic processes defined on trees, it turns out to be effective also for out-of-equilibrium processes on sparse loopy networks.

  5. Tensor integrand reduction via Laurent expansion

    DOE PAGES

    Hirschi, Valentin; Peraro, Tiziano

    2016-06-09

    We introduce a new method for the application of one-loop integrand reduction via the Laurent expansion algorithm, as implemented in the public C++ library Ninja. We show how the coefficients of the Laurent expansion can be computed by suitable contractions of the loop numerator tensor with cut-dependent projectors, making it possible to interface Ninja to any one-loop matrix element generator that can provide the components of this tensor. We implemented this technique in the Ninja library and interfaced it to MadLoop, which is part of the public MadGraph5_aMC@NLO framework. We performed a detailed performance study, comparing against other public reductionmore » tools, namely CutTools, Samurai, IREGI, PJFry++ and Golem95. We find that Ninja out-performs traditional integrand reduction in both speed and numerical stability, the latter being on par with that of the tensor integral reduction tool Golem95 which is however more limited and slower than Ninja. Lastly, we considered many benchmark multi-scale processes of increasing complexity, involving QCD and electro-weak corrections as well as effective non-renormalizable couplings, showing that Ninja’s performance scales well with both the rank and multiplicity of the considered process.« less

  6. Voltage-induced reduction of graphene oxide

    NASA Astrophysics Data System (ADS)

    Faucett, Austin C.

    Graphene Oxide (GO) is being widely researched as a precursor for the mass production of graphene, and as a versatile material in its own right for flexible electronics, chemical sensors, and energy harvesting applications. Reduction of GO, an electrically insulating material, into reduced graphene oxide (rGO) restores electrical conductivity via removal of oxygen-containing functional groups. Here, a reduction method using an applied electrical bias, known as voltage-induced reduction, is explored. Voltage-induced reduction can be performed under ambient conditions and avoids the use of hazardous chemicals or high temperatures common with standard methods, but little is known about the reduction mechanisms and the quality of rGO produced with this method. This work performs extensive structural and electrical characterization of voltage-reduced GO (V-rGO) and shows that it is competitive with standard methods. Beyond its potential use as a facile and eco-friendly processing approach, V-rGO reduction also offers record high-resolution patterning capabilities. In this work, the spatial resolution limits of voltage-induced reduction, performed using a conductive atomic force microscope probe, are explored. It is shown that arbitrary V-rGO conductive features can be patterned into insulating GO with nanoscale resolution. The localization of voltage-induced reduction to length scales < 10 nm allows studies of reduction reaction kinetics, using electrical current obtained in-situ, with statistical robustness. Methods for patterning V-rGO nanoribbons are then developed. After presenting sub-10nm patterning of V-rGO nanoribbons in GO single sheets and films, the performance of V-rGO nanoribbon field effect transistors (FETs) are demonstrated. Preliminary measurements show an increase in electrical current on/off ratios as compared to large-area rGO FETs, indicating transport gap modulation that is possibly due to quantum confinement effects.

  7. Alkaline dehydration of anion-exchanged human urine: Volume reduction, nutrient recovery and process optimisation.

    PubMed

    Simha, Prithvi; Senecal, Jenna; Nordin, Annika; Lalander, Cecilia; Vinnerås, Björn

    2018-06-02

    In urine-separating sanitation systems, bacterial urease enzymes can hydrolyse urea to ammonia during the pipe transport and storage of urine. The present study investigated whether it was possible to reduce the urine volume without losing the nitrogen as ammonia. A method for stabilising the urine prior to dehydration was developed. Briefly, fresh human urine was stabilised by passage through an anion-exchanger, added to an alkaline media (wood ash or alkalised biochar), and dehydrated. Urine dehydration was investigated at three temperatures: 40, 45 and 50 °C. The influence of various factors affecting the dehydration process was modelled and the rate of urine dehydration was optimised. Results indicated that 75% (v/v) of the urine has to pass through the ion-exchanger for alkaline stabilisation of urine to occur. At all investigated temperatures, the dehydrator accomplished >90% volume reduction of ion-exchanged urine, > 70% N retention and 100% recovery of P and K. To realise high degree of nutrient valorisation, this study proposes combining source-separation of human urine with alkaline dehydration. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Overview of reductants utilized in nuclear fuel reprocessing/recycling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Paviet-Hartmann, P.; Riddle, C.; Campbell, K.

    2013-07-01

    The most widely used reductant to partition plutonium from uranium in the Purex process was ferrous sulfamate, other alternates were proposed such as hydrazine-stabilized ferrous nitrate or uranous nitrate, platinum catalyzed hydrogen, and hydrazine, hydroxylamine salts. New candidates to replace hydrazine or hydroxylamine nitrate (HAN) are pursued worldwide. They may improve the performance of the industrial Purex process towards different operations such as de-extraction of plutonium and reduction of the amount of hydrazine which will limit the formation of hydrazoic acid. When looking at future recycling technologies using hydroxamic ligands, neither acetohydroxamic acid (AHA) nor formohydroxamic acid (FHA) seem promisingmore » because they hydrolyze to give hydroxylamine and the parent carboxylic acid. Hydroxyethylhydrazine, HOC{sub 2}H{sub 4}N{sub 2}H{sub 3} (HEH) is a promising non-salt-forming reductant of Np and Pu ions because it is selective to neptunium and plutonium ions at room temperature and at relatively low acidity, it could serve as a replacement of HAN or AHA for the development of a novel used nuclear fuel recycling process.« less

  9. Poverty Reduction Begins with Children.

    ERIC Educational Resources Information Center

    United Nations Children's Fund, New York, NY.

    This report describes how children bear the brunt of poverty and explains why they are central to poverty reduction in developing nations. The report also illustrates UNICEF's support for the process of improving access to, and quality of, health care, education, water and sanitation, and child protection. It describes how the participation of the…

  10. Lithium metal reduction of plutonium oxide to produce plutonium metal

    DOEpatents

    Coops, Melvin S.

    1992-01-01

    A method is described for the chemical reduction of plutonium oxides to plutonium metal by the use of pure lithium metal. Lithium metal is used to reduce plutonium oxide to alpha plutonium metal (alpha-Pu). The lithium oxide by-product is reclaimed by sublimation and converted to the chloride salt, and after electrolysis, is removed as lithium metal. Zinc may be used as a solvent metal to improve thermodynamics of the reduction reaction at lower temperatures. Lithium metal reduction enables plutonium oxide reduction without the production of huge quantities of CaO--CaCl.sub.2 residues normally produced in conventional direct oxide reduction processes.

  11. Sludge reduction and microbial community structure in an anaerobic/anoxic/oxic process coupled with potassium ferrate disintegration.

    PubMed

    An, Ying; Zhou, Zhen; Yao, Jie; Niu, Tianhao; Qiu, Zhan; Ruan, Danian; Wei, Haijuan

    2017-12-01

    An anaerobic/anoxic/oxic (AAO) wastewater treatment system combining with a potassium ferrate (K 2 FeO 4 ) oxidation side-stream reactor (SSR) was proposed for sludge reduction. Batch experiments showed that optimal K 2 FeO 4 dosage and reaction time for sludge disintegration was 100mg/g suspended solids (SS) and 24h, respectively. Subsequently, an AAO-SSR and a conventional AAO were operated in parallel to investigate effects of K 2 FeO 4 oxidation on process performance, sludge characteristics and microbial community structures. The AAO-SSR process operated under the optimized condition achieved efficient COD and NH 4 + -N removal, and reduced sludge by 47.5% with observed yield coefficient of 0.21gSS/g COD. K 2 FeO 4 addition broke sludge particles, increased dissolved organic matters in the mixed liquor, and improved sludge dewaterability. Illumina-MiSeq sequencing results showed that K 2 FeO 4 oxidation in the AAO-SSR decreased microbial richness and diversity, enriched slow growers (Dechloromonas), anaerobic fermentative bacteria (Azospira) and Fe(III)-reducing bacteria (Ferribacterium), but limited the growth of phosphate-accumulating organisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Alcohol policy and harm reduction in Australia.

    PubMed

    Loxley, Wendy; Gray, Dennis; Wilkinson, Celia; Chikritzhs, Tanya; Midford, Richard; Moore, David

    2005-11-01

    With consultations having been held across Australia this year as part of the process of developing a new National Alcohol Strategy, it seemed timely to invite my colleagues from the National Drug Research Institute who are experts in the alcohol field to write this Harm Reduction Digest. The authors have canvassed a range of alcohol policy options and discussed their effectiveness in reducing harm for what is arguably Australia's number one drug problem. Australia's response to alcohol and other drug problems has, historically, been based on 'harm minimization--incorporating supply reduction, demand reduction and harm reduction'. At this time where the policy options for alcohol are being set for the next 5 years in a climate of 'small government', removing restrictions of 'fair competition' in business and a belief in the free market, what does the research have to say about recommended policies and strategies to reduce alcohol-related harm?

  13. Fe Isotope Fractionation During Fe(III) Reduction to Fe(II)

    NASA Astrophysics Data System (ADS)

    Baker, E. A.; Greene, S.; Hardin, E. E.; Hodierne, C. E.; Rosenberg, A.; John, S.

    2014-12-01

    The redox chemistry of Fe(III) and Fe(II) is tied to a variety of earth processes, including biological, chemical, or photochemical reduction of Fe(III) to Fe(II). Each process may fractionate Fe isotopes, but the magnitudes of the kinetic isotope effects have not been greatly explored in laboratory conditions. Here, we present the isotopic fractionation of Fe during reduction experiments under a variety of experimental conditions including photochemical reduction of Fe(III) bound to EDTA or glucaric acid, and chemical reduction of Fe-EDTA by sodium dithionite, hydroxylamine hydrochloride, Mn(II), and ascorbic acid. A variety of temperatures and pHs were tested. In all experiments, Fe(III) bound to an organic ligand was reduced in the presence of ferrozine. Ferrozine binds with Fe(II), forming a purple complex which allows us to measure the extent of reaction. The absorbance of the experimental solutions was measured over time to determine the Fe(II)-ferrozine concentration and thus the reduction rate. After about 5% of the Fe(III) was reduced, Fe(III)-EDTA and Fe(II)-ferrozine were separated using a C-18 column to which Fe(II)-ferrozine binds. The Fe(II) was eluted and purified through anion exchange chromatography for analysis of δ56Fe by MC-ICPMS. Preliminary results show that temperature and pH both affect reduction rate. All chemical reductants tested reduce Fe(III) at a greater rate as temperature increases. The photochemical reductant EDTA reduces Fe(III) at a greater rate under more acidic conditions. Comparison of the two photochemical reductants shows that glucaric acid reduces Fe(III) significantly faster than EDTA. For chemical reduction, the magnitude of isotopic fractionation depends on the reductant used. Temperature and pH also affect the isotopic fractionation of Fe. Experiments using chemical reductants show that an increase in temperature at low temperatures produces lighter 56Fe ratios, while at high temperatures some reductants produce heavier

  14. Earthquake risk reduction in the United States: An assessment of selected user needs and recommendations for the National Earthquake Hazards Reduction Program

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1994-12-31

    This Assessment was conducted to improve the National Earthquake Hazards Reduction Program (NEHRP) by providing NEHRP agencies with information that supports their user-oriented setting of crosscutting priorities in the NEHRP strategic planning process. The primary objective of this Assessment was to take a ``snapshot`` evaluation of the needs of selected users throughout the major program elements of NEHRP. Secondary objectives were to conduct an assessment of the knowledge that exists (or is being developed by NEHRP) to support earthquake risk reduction, and to begin a process of evaluating how NEHRP is meeting user needs. An identification of NEHRP`s strengths alsomore » resulted from the effort, since those strengths demonstrate successful methods that may be useful to NEHRP in the future. These strengths are identified in the text, and many of them represent important achievements since the Earthquake Hazards Reduction Act was passed in 1977.« less

  15. Enhancing the Process of Anaerobic Ammonium Oxidation Coupled to Iron Reduction in Constructed Wetland Mesocosms with Supplementation of Ferric Iron Hydroxides

    NASA Astrophysics Data System (ADS)

    Shuai, W.; Jaffe, P. R.

    2017-12-01

    Effective ammonium (NH4+) removal has been a challenge in wastewater treatment processes. Aeration, which is required for the conventional NH4+ removal approach by ammonium oxidizing bacteria, is an energy intensive process during the operation of wastewater treatment plant. The efficiency of NH4+ oxidation in natural systems is also limited by oxygen transfer in water and sediments. The objective of this study is to enhance NH4+ removal by applying a novel microbial process, anaerobic NH4+ oxidation coupled to iron (Fe) reduction (also known as Feammox), in constructed wetlands (CW). Our studies have shown that an Acidimicrobiaceae bacterium named A6 can carry out the Feammox process using ferric Fe (Fe(III)) minerals like ferrihydrite as their electron acceptor. To investigate the properties of the Feammox process in CW as well as the influence of electrodes, Feammox bacterium A6 was inoculated in planted CW mesocosms with electrodes installed at multiple depths. CW mesocosms were operated using high NH4+ nutrient solution as inflow under high or low sediment Fe(III) level. During the operation, NH4+ and ferrous Fe concentration, pore water pH, voltages between electrodes, oxidation reduction potential and dissolved oxygen were measured. At the end of the experiment, CW sediment samples at different depths were taken, DNAs were extracted and quantitative polymerase chain reaction and pyrosequencing were performed to analyze the microbial communities. The results show that the high Fe level CW mesocosm has much higher NH4+ removal ability than the low Fe level CW mesocosm after Fe-reducing conditions are developed. This indicates the enhanced NH4+ removal can be attributed to elevated Feammox activity in high Fe level CW mesocosm. The microbial community structures are different in high or low Fe level CW mesocosms and on or away from the installed electrodes. The voltages between cathode and anode increased after the injection of A6 enrichment culture in low Fe

  16. Tensor sufficient dimension reduction

    PubMed Central

    Zhong, Wenxuan; Xing, Xin; Suslick, Kenneth

    2015-01-01

    Tensor is a multiway array. With the rapid development of science and technology in the past decades, large amount of tensor observations are routinely collected, processed, and stored in many scientific researches and commercial activities nowadays. The colorimetric sensor array (CSA) data is such an example. Driven by the need to address data analysis challenges that arise in CSA data, we propose a tensor dimension reduction model, a model assuming the nonlinear dependence between a response and a projection of all the tensor predictors. The tensor dimension reduction models are estimated in a sequential iterative fashion. The proposed method is applied to a CSA data collected for 150 pathogenic bacteria coming from 10 bacterial species and 14 bacteria from one control species. Empirical performance demonstrates that our proposed method can greatly improve the sensitivity and specificity of the CSA technique. PMID:26594304

  17. Plasma expansion dynamics physics: An understanding on ion energy reduction process

    NASA Astrophysics Data System (ADS)

    Ruzic, David; Srivastava, Shailendra; Thompson, Keith; Spencer, Joshua; Sporre, John

    2007-11-01

    This paper studies the expanding plasma dynamics of ions produced from a 5J Z-pinch xenon light source used for EUV lithography. Ion energy reduction is essential for the successful implementation of this technology. To aid this investigation, ion energy from a z-pinch DPP plasma source is measured using an ion energy analyzer and effect of introducing a small percentage of low Z material on the ion energy and flux is investigated. Presence of low mass such as H2 or N2, shows a considerable reduction in total flux and in average energy. For example, Xe^+ ion flux at 5 keV are recorded as 425 ± 42 ions/cm^2.eV.pulse at 157 cm and reduced to 125 ± 12 ions/cm^2.eV.pulse when using the low mass into the system at same energy. It is also noticed that such a combination leads to decrease in sputtering without changing the EUV output. Study of the possible mechanism supporting the experimental results is numerically calculated. This computational work indicates that the observed high energies of ions are probably resulting from coulomb explosion initiated by pinch instability. It is postulated that the electrons leave first setting up an electrostatic potential which accelerates the ions. The addition of small mass actually screens the potential and decorates the ions.

  18. Simultaneous removal of NOx and SO2 from flue gas using combined Na2SO3 assisted electrochemical reduction and direct electrochemical reduction.

    PubMed

    Guo, Qingbin; He, Yi; Sun, Tonghua; Wang, Yalin; Jia, Jinping

    2014-07-15

    A method combining Na2SO3 assisted electrochemical reduction and direct electrochemical reduction using Fe(II)(EDTA) solution was proposed to simultaneously remove NOx and SO2 from flue gas. Activated carbon was used as catalyst to accelerate the process. This new system features (a) direct conversion of NOx and SO2 to harmless N2 and SO4(2-); (b) fast regeneration of Fe(II)(EDTA); (c) minimum use of chemical reagents; and (d) recovery of the reduction by-product (Na2SO4). Fe(II)(EDTA) solution was continuously recycled and reused during entire process, and no harmful waste was generated. Approximately 99% NOx and 98% SO2 were removed under the optimal condition. The stability test showed that the system operation was reliable. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Technologies for Turbofan Noise Reduction

    NASA Technical Reports Server (NTRS)

    Huff, Dennis

    2005-01-01

    An overview presentation of NASA's engine noise research since 1992 is given for subsonic commercial aircraft applications. Highlights are included from the Advanced Subsonic Technology (AST) Noise Reduction Program and the Quiet Aircraft Technology (QAT) project with emphasis on engine source noise reduction. Noise reduction goals for 10 EPNdB by 207 and 20 EPNdB by 2022 are reviewed. Fan and jet noise technologies are highlighted from the AST program including higher bypass ratio propulsion, scarf inlets, forward-swept fans, swept/leaned stators, chevron nozzles, noise prediction methods, and active noise control for fans. Source diagnostic tests for fans and jets that have been completed over the past few years are presented showing how new flow measurement methods such as Particle Image Velocimetry (PIV) have played a key role in understanding turbulence, the noise generation process, and how to improve noise prediction methods. Tests focused on source decomposition have helped identify which engine components need further noise reduction. The role of Computational AeroAcoustics (CAA) for fan noise prediction is presented. Advanced noise reduction methods such as Hershel-Quincke tubes and trailing edge blowing for fan noise that are currently being pursued n the QAT program are also presented. Highlights are shown form engine validation and flight demonstrations that were done in the late 1990's with Pratt & Whitney on their PW4098 engine and Honeywell on their TFE-731-60 engine. Finally, future propulsion configurations currently being studied that show promise towards meeting NASA's long term goal of 20 dB noise reduction are shown including a Dual Fan Engine concept on a Blended Wing Body aircraft.

  20. In vivo photosystem I reduction in thermophilic and mesophilic cyanobacteria: the thermal resistance of the process is limited by factors other than the unfolding of the partners.

    PubMed

    Durán, Raúl V; Hervás, Manuel; De la Rosa, Miguel A; Navarro, José A

    2005-08-19

    Photosystem I reduction by plastocyanin and cytochrome c(6) in cyanobacteria has been extensively studied in vitro, but much less information is provided on this process inside the cell. Here, we report an analysis of the electron transfer from both plastocyanin and cytochrome c(6) to photosystem I in intact cells of several cyanobacterial species, including a comparative study of the temperature effect in mesophilic and thermophilic organisms. Our data show that cytochrome c(6) reduces photosystem I by following a reaction mechanism involving complex formation, whereas the copper-protein follows a simpler collisional mechanism. These results contrast with previous kinetic studies in vitro. The effect of temperature on photosystem I reduction leads us to conclude that the thermal resistance of this process is determined by factors other than the proper stability of the protein partners.

  1. Evaluating best practices for Campylobacter and Salmonella reduction in poultry processing plants.

    PubMed

    Wideman, N; Bailey, M; Bilgili, S F; Thippareddi, H; Wang, L; Bratcher, C; Sanchez-Plata, M; Singh, M

    2016-02-01

    Poultry processing plants in the United States were surveyed on their current Campylobacter and Salmonella control practices. Following surveys, data were collected to develop a baseline for prevalence rates of Salmonella and Campylobacter; then changes in practices were implemented and evaluated for improvements in pathogen control. Surveys were sent to the plant Quality Assurance managers to determine production levels, antimicrobial interventions, and current pathogen testing practices. Initial sampling was performed at 6 plants with similar production volumes, at sites that included carcass samples before any pre-evisceration intervention, after exiting the inside-outside bird washer (IOBW), after exiting the pre-chiller, after exiting the primary chiller, and after exiting any post-chill intervention, as well as a water sample from each scalder, pre-chiller, primary chiller, and post-chill dip tank or finishing chiller. Enumerations and enrichments were performed for Campylobacter and Salmonella. Following the baseline sampling, changes in practices were suggested for each plant and a second sampling was conducted to determine their effectiveness. Results demonstrated that peracetic acid (PAA) was the most effective (P < 0.05) antimicrobial currently in use. The use of a post-chill antimicrobial immersion tank and/or use of a cetylpyridinium chloride (CPC) spray cabinet also displayed a further reduction in microbial levels (P < 0.05) when the primary chiller was not sufficient (P > 0.05). Microbial buildup in the immersion tanks demonstrates the need for effective cleaning, sanitation practices, and chiller maintenance to reduce contamination of poultry with Campylobacter and Salmonella. © 2015 Poultry Science Association Inc.

  2. Reduction, partial evaporation, and spattering - Possible chemical and physical processes in fluid drop chondrule formation

    NASA Technical Reports Server (NTRS)

    King, E. A.

    1983-01-01

    The major chemical differences between fluid drop chondrules and their probable parent materials may have resulted from the loss of volatiles such as S, H2O, Fe, and volatile siderophile elements by partial evaporation during the chondrule-forming process. Vertical access solar furnace experiments in vacuum and hydrogen have demonstrated such chemical fractionation trends using standard rock samples. The formation of immiscible iron droplets and spherules by in situ reduction of iron from silicate melt and the subsequent evaporation of the iron have been observed directly. During the time that the main sample bead is molten, many small spatter spherules are thrown off the main bead, thereby producing many additional chondrule-like melt spherules that cool rapidly and generate a population of spherules with size frequency distribution characteristics that closely approximate some populations of fluid drop chondrules in chondrites. It is possible that spatter-produced fluid drop chondrules dominate the meteoritic fluid drop chondrule populations. Such meteoritic chondrule populations should be chemically related by various relative amounts of iron and other volatile loss by vapor fractionation.

  3. Ammonium stimulates nitrate reduction during simultaneous nitrification and denitrification process by Arthrobacter arilaitensis Y-10.

    PubMed

    He, Tengxia; Xie, Deti; Li, Zhenlun; Ni, Jiupai; Sun, Quan

    2017-09-01

    The ability of Arthrobacter arilaitensis Y-10 for nitrogen removal from simulated wastewater was studied. Results showed that ammonium was the best inorganic nitrogen for strain Y-10's cell growth, which could also promote nitrate reduction. Approximately 100.0% of ammonium was removed in the nitrogen removal experiments. The nitrate removal efficiency was 73.3% with nitrate as sole nitrogen source, and then the nitrate efficiency was increased to 85.3% and 100.0% with ammonium and nitrate (both about 5 or 100mg/L) as the mixed nitrogen sources. Nitrite accumulation was observed in presence of ammonium and nitrate. When the concentration of sole nitrite nitrogen was 10.31mg/L, the nitrite removal efficiency was 100.0%. Neither ammonium nor nitrate was accumulated during the whole experimental process. All experimental results indicated that A. arilaitensis Y-10 could remove ammonium, nitrate and nitrite at 15°C from wastewater, and could also perform simultaneous nitrification and denitrification under aerobic condition. Copyright © 2017. Published by Elsevier Ltd.

  4. Role of DDL processes during electrolytic reduction of Cu(II) in a low oxygen environment.

    PubMed

    Brosky, Rebekah T; Pamukcu, Sibel

    2013-11-15

    Heavy metals typically accumulate in reduced bottom sediments after being discharged into waterways by industrial and municipal processes. A laboratory experiment was conducted in order to determine if abundance of clay in the bottom sediments of a Cu-contaminated aqueous ecosystem could enhance electrolytic reduction of the heavy metal. Cu(NO3)2 · 2.5H2O was added to simulate a moderately contaminated system with 650 μg Cu/ml kaolinite clay-water slurry. A constant electrical potential of 1.0 V/cm was applied across platinum wire electrodes inserted into the continuously stirred system for four days while the system ORP(2) was monitored and periodic sub-samples were taken for analysis. The electrical as well as the chemical results indicate that the quantity of Cu(II) being reduced to Cu(I), especially within the aqueous phase, is increased within the first 48 h of experimentation by the presence of kaolinite clay up to 0.05 mg clay/l slurry. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Mechanochemical processing for metals and metal alloys

    DOEpatents

    Froes, Francis H.; Eranezhuth, Baburaj G.; Prisbrey, Keith

    2001-01-01

    A set of processes for preparing metal powders, including metal alloy powders, by ambient temperature reduction of a reducible metal compound by a reactive metal or metal hydride through mechanochemical processing. The reduction process includes milling reactants to induce and complete the reduction reaction. The preferred reducing agents include magnesium and calcium hydride powders. A process of pre-milling magnesium as a reducing agent to increase the activity of the magnesium has been established as one part of the invention.

  6. Reduction Rates for Higher Americium Oxidation States in Nitric Acid

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Grimes, Travis Shane; Mincher, Bruce Jay; Schmitt, Nicholas C

    The stability of hexavalent americium was measured using multiple americium concentrations and nitric acid concentrations after contact with the strong oxidant sodium bismuthate. Contrary to our hypotheses Am(VI) was not reduced faster at higher americium concentrations, and the reduction was only zero-order at short time scales. Attempts to model the reduction kinetics using zero order kinetic models showed Am(VI) reduction in nitric acid is more complex than the autoreduction processes reported by others in perchloric acid. The classical zero-order reduction of Am(VI) was found here only for short times on the order of a few hours. We did show thatmore » the rate of Am(V) production was less than the rate of Am(VI) reduction, indicating that some Am(VI) undergoes two electron-reduction to Am(IV). We also monitored the Am(VI) reduction in contact with the organic diluent dodecane. A direct comparison of these results with those in the absence of the organic diluent showed the reduction rates for Am(VI) were not statistically different for both systems. Additional americium oxidations conducted in the presence of Ce(IV)/Ce(III) ions showed that Am(VI) is reduced without the typical growth of Am(V) observed in the systems sans Ce ion. This was an interesting result which suggests a potential new reduction/oxidation pathway for Am in the presence of Ce; however, these results were very preliminary, and will require additional experiments to understand the mechanism by which this occurs. Overall, these studies have shown that hexavalent americium is fundamentally stable enough in nitric acid to run a separations process. However, the complicated nature of the reduction pathways based on the system components is far from being rigorously understood.« less

  7. REDUCTIVE DEHALOGENATION OF HALOMETHANES IN NATURAL AND MODEL SYSTEMS: QSAR ANALYSIS

    EPA Science Inventory

    Reductive dehalogenation is a dominant reaction pathway for halogenated organics in anoxic environments. Towards the goal of developing predictive tools for this reaction process, the reduction kinetics for a series of halomethanes were measured in batch studies with both natural...

  8. Molecular dynamics simulation of cytochrome c3: studying the reduction processes using free energy calculations.

    PubMed Central

    Soares, C M; Martel, P J; Mendes, J; Carrondo, M A

    1998-01-01

    The tetraheme cytochrome c3 from Desulfovibrio vulgaris Hildenborough is studied using molecular dynamics simulation studies in explicit solvent. The high heme content of the protein, which has its core almost entirely made up of c-type heme, presents specific problems in the simulation. Instability in the structure is observed in long simulations above 1 ns, something that does not occur in a monoheme cytochrome, suggesting problems in heme parametrization. Given these stability problems, a partially restrained model, which avoids destruction of the structure, was created with the objective of performing free energy calculations of heme reduction, studies that require long simulations. With this model, the free energy of reduction of each individual heme was calculated. A correction in the long-range electrostatic interactions of charge groups belonging to the redox centers had to be made in order to make the system physically meaningful. Correlation is obtained between the calculated free energies and the experimental data for three of four hemes. However, the relative scale of the calculated energies is different from the scale of the experimental free energies. Reasons for this are discussed. In addition to the free energy calculations, this model allows the study of conformational changes upon reduction. Even if the precise details of the structural changes that take place in this system upon individual heme reduction are probably out of the reach of this study, it appears that these structural changes are small, similarly to what is observed for other redox proteins. This does not mean that their effect is minor, and one example is the conformational change observed in propionate D from heme I when heme II becomes reduced. A motion of this kind could be the basis of the experimentally observed cooperativity effects between heme reduction, namely positive cooperativity. PMID:9545034

  9. Field Demonstration of a Novel Biotreatment Process for Perchlorate Reduction in Groundwater

    DTIC Science & Technology

    2010-06-01

    biological reduction and/or reaction with ZVI, and arsenic hexavalent chromium and/or uranium by adsorption on corrosion products. • Simple rugged...problems and troubleshooting measures ................................... 22 5.2 Laboratory Evaluation of Porosity Decrease and Corrosion Products...reactor when it was dismantled showing the heavy deposits of iron corrosion products and quasi total loss of porosity. Figure 5.14 Picture of the column

  10. Cognitive Dissonance Reduction as Constraint Satisfaction.

    ERIC Educational Resources Information Center

    Shultz, Thomas R.; Lepper, Mark R.

    1996-01-01

    It is argued that the reduction of cognitive dissonance can be viewed as a constraint satisfaction problem, and a computational model of the process of consonance seeking is proposed. Simulations from this model matched psychological findings from the insufficient justification and free-choice paradigms of cognitive dissonance theory. (SLD)

  11. ORAC-DR -- SCUBA-2 Pipeline Data Reduction

    NASA Astrophysics Data System (ADS)

    Gibb, Andrew G.; Jenness, Tim

    The ORAC-DR data reduction pipeline is designed to reduce data from many different instruments. This document describes how to use ORAC-DR to process data taken with the SCUBA-2 instrument on the James Clerk Maxwell Telescope.

  12. Directions of the US Geological Survey Landslide Hazards Reduction Program

    USGS Publications Warehouse

    Wieczorek, G.F.

    1993-01-01

    The US Geological Survey (USGS) Landslide Hazards Reduction Program includes studies of landslide process and prediction, landslide susceptibility and risk mapping, landslide recurrence and slope evolution, and research application and technology transfer. Studies of landslide processes have been recently conducted in Virginia, Utah, California, Alaska, and Hawaii, Landslide susceptibility maps provide a very important tool for landslide hazard reduction. The effects of engineering-geologic characteristics of rocks, seismic activity, short and long-term climatic change on landslide recurrence are under study. Detailed measurement of movement and deformation has begun on some active landslides. -from Author

  13. Reductive dehalogenase structure suggests a mechanism for B12-dependent dehalogenation.

    PubMed

    Payne, Karl Ap; Quezada, Carolina P; Fisher, Karl; Dunstan, Mark S; Collins, Fraser A; Sjuts, Hanno; Levy, Colin; Hay, Sam; Rigby, Stephen Ej; Leys, David

    2015-01-22

    Organohalide chemistry underpins many industrial and agricultural processes, and a large proportion of environmental pollutants are organohalides. Nevertheless, organohalide chemistry is not exclusively of anthropogenic origin, with natural abiotic and biological processes contributing to the global halide cycle. Reductive dehalogenases are responsible for biological dehalogenation in organohalide respiring bacteria, with substrates including polychlorinated biphenyls or dioxins. Reductive dehalogenases form a distinct subfamily of cobalamin (B12)-dependent enzymes that are usually membrane associated and oxygen sensitive, hindering detailed studies. Here we report the characterization of a soluble, oxygen-tolerant reductive dehalogenase and, by combining structure determination with EPR (electron paramagnetic resonance) spectroscopy and simulation, show that a direct interaction between the cobalamin cobalt and the substrate halogen underpins catalysis. In contrast to the carbon-cobalt bond chemistry catalysed by the other cobalamin-dependent subfamilies, we propose that reductive dehalogenases achieve reduction of the organohalide substrate via halogen-cobalt bond formation. This presents a new model in both organohalide and cobalamin (bio)chemistry that will guide future exploitation of these enzymes in bioremediation or biocatalysis.

  14. Continuous Adaptive Population Reduction (CAPR) for Differential Evolution Optimization.

    PubMed

    Wong, Ieong; Liu, Wenjia; Ho, Chih-Ming; Ding, Xianting

    2017-06-01

    Differential evolution (DE) has been applied extensively in drug combination optimization studies in the past decade. It allows for identification of desired drug combinations with minimal experimental effort. This article proposes an adaptive population-sizing method for the DE algorithm. Our new method presents improvements in terms of efficiency and convergence over the original DE algorithm and constant stepwise population reduction-based DE algorithm, which would lead to a reduced number of cells and animals required to identify an optimal drug combination. The method continuously adjusts the reduction of the population size in accordance with the stage of the optimization process. Our adaptive scheme limits the population reduction to occur only at the exploitation stage. We believe that continuously adjusting for a more effective population size during the evolutionary process is the major reason for the significant improvement in the convergence speed of the DE algorithm. The performance of the method is evaluated through a set of unimodal and multimodal benchmark functions. In combining with self-adaptive schemes for mutation and crossover constants, this adaptive population reduction method can help shed light on the future direction of a completely parameter tune-free self-adaptive DE algorithm.

  15. A Theory of Perceptual Learning: Uncertainty Reduction and Reading.

    ERIC Educational Resources Information Center

    Henk, William A.

    Behaviorism cannot adequately explain language processing. A synthesis of the psycholinguistic and information processing approaches of cognitive psychology, however, can provide the basis for a speculative analysis of reading, if this synthesis is tempered by a perceptual learning theory of uncertainty reduction. Theorists of information…

  16. Mobil-Badger technologies for benzene reduction in gasoline

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goelzer, A.R.; Ram, S.; Hernandez, A.

    1993-01-01

    Many refiners will need to reduce the barrels per day of benzene entering the motor gasoline pool. Mobil and Badger have developed and now jointly license three potential refinery alternatives to conventional benzene hydrosaturation to achieve this: Mobil Benzene Reduction, Ethylbenzene and Cumene. The Mobil Benzene Reduction Process (MBR) uses dilute olefins in FCC offgas to extensively alkylate dilute benzene as found in light reformate, light FCC gasoline, or cyclic C[sub 6] naphtha. MBR raises octanes and lowers C[sub 5]+ olefins. MBR does not involve costly hydrogen addition. The refinery-based Mobil/Badger Ethylbenzene Process reacts chemical-grade benzene extracted from light reformatemore » with dilute ethylene found in treated FCC offgas to make high-purity ethylbenzene. EB is the principal feedstock for the production of styrene. The Mobil/Badger Cumene Process alkylates FCC-derived dilute propylene and extracted benzene to selectively yield isopropyl benzene (cumene). Cumene is the principal feedstock for the production of phenol. All three processes use Mobil developed catalysts.« less

  17. Molten salt applications in materials processing

    NASA Astrophysics Data System (ADS)

    Mishra, Brajendra; Olson, David L.

    2005-02-01

    The science of molten salt electrochemistry for electrowinning of reactive metals, such as calcium, and its in situ application in pyro-reduction has been described. Calcium electrowinning has been performed in a 5 10 wt% calcium oxide calcium chloride molten salt by the electrolytic dissociation of calcium oxide. This electrolysis requires the use of a porous ceramic sheath around the anode to keep the cathodically deposited calcium and the anodic gases separate. Stainless steel cathode and graphite anode have been used in the temperature range of 850 950 °C. This salt mixture is produced as a result of the direct oxide reduction (DOR) of reactive metal oxides by calcium in a calcium chloride bath. The primary purpose of this process is to recover the expensive calcium reductant and to recycle calcium chloride. Experimental data have been included to justify the suitability as well as limitations of the electrowinning process. Transport of oxygen ions through the sheath is found to be the rate controlling step. Under the constraints of the reactor design, a calcium recovery rate of approx. 150 g/h was achieved. Feasibility of a process to produce metals by pyrometallurgical reduction, using the calcium reductant produced electrolytically within the same reactor, has been shown in a hybrid process. Several processes are currently under investigation to use this electrowon calcium for in situ reduction of metal oxides.

  18. Electrochemical reduction of carbon dioxide. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    LaConti, A.B.; Molter, T.M.; Zagaja, J.A.

    1986-05-01

    Many researchers have studied the electrochemical reduction of carbon dioxide and related organic species to form concentrated liquid/gaseous products in laboratory-scale hardware. Hamilton Standard has developed a high pressure SPE electrolysis cell capable of reducing carbon dioxide streams to form pure, concentrated alcohols, carboxylic acids, and other hydrocarbons. The process is unique in that the byproducts of reaction include oxygen and, under some test conditions water. In addition, a relatively simple test system was designed and constructed permitting both batch and semibatch type electrochemical reduction studies. In this study, cathode materials were developed which 1) had a characteristic high hydrogenmore » overvoltage, and 2) possessed the intrinsic affinity for electrochemical reduction of the carbon dioxide species. In addition, suitable anode electrocatalyst materials were identified. Studies involving the electrochemical reduction of carbon dioxide required the ability to identify and quantify reaction products obtained during cell evaluation. Gas chromatographic techniques were developed along with the establishment of ion chromatographic methods permitting the analysis of organic reaction products. Hamilton Standard has evaluated electrochemical carbon dioxide reduction cells under a variety of test conditions.« less

  19. Application of CRAFT (complete reduction to amplitude frequency table) in nonuniformly sampled (NUS) 2D NMR data processing.

    PubMed

    Krishnamurthy, Krish; Hari, Natarajan

    2017-09-15

    The recently published CRAFT (complete reduction to amplitude frequency table) technique converts the raw FID data (i.e., time domain data) into a table of frequencies, amplitudes, decay rate constants, and phases. It offers an alternate approach to decimate time-domain data, with minimal preprocessing step. It has been shown that application of CRAFT technique to process the t 1 dimension of the 2D data significantly improved the detectable resolution by its ability to analyze without the use of ubiquitous apodization of extensively zero-filled data. It was noted earlier that CRAFT did not resolve sinusoids that were not already resolvable in time-domain (i.e., t 1 max dependent resolution). We present a combined NUS-IST-CRAFT approach wherein the NUS acquisition technique (sparse sampling technique) increases the intrinsic resolution in time-domain (by increasing t 1 max), IST fills the gap in the sparse sampling, and CRAFT processing extracts the information without loss due to any severe apodization. NUS and CRAFT are thus complementary techniques to improve intrinsic and usable resolution. We show that significant improvement can be achieved with this combination over conventional NUS-IST processing. With reasonable sensitivity, the models can be extended to significantly higher t 1 max to generate an indirect-DEPT spectrum that rivals the direct observe counterpart. Copyright © 2017 John Wiley & Sons, Ltd.

  20. Entanglement enhancement through multirail noise reduction for continuous-variable measurement-based quantum-information processing

    NASA Astrophysics Data System (ADS)

    Su, Yung-Chao; Wu, Shin-Tza

    2017-09-01

    We study theoretically the teleportation of a controlled-phase (cz) gate through measurement-based quantum-information processing for continuous-variable systems. We examine the degree of entanglement in the output modes of the teleported cz-gate for two classes of resource states: the canonical cluster states that are constructed via direct implementations of two-mode squeezing operations and the linear-optical version of cluster states which are built from linear-optical networks of beam splitters and phase shifters. In order to reduce the excess noise arising from finite-squeezed resource states, teleportation through resource states with different multirail designs will be considered and the enhancement of entanglement in the teleported cz gates will be analyzed. For multirail cluster with an arbitrary number of rails, we obtain analytical expressions for the entanglement in the output modes and analyze in detail the results for both classes of resource states. At the same time, we also show that for uniformly squeezed clusters the multirail noise reduction can be optimized when the excess noise is allocated uniformly to the rails. To facilitate the analysis, we develop a trick with manipulations of quadrature operators that can reveal rather efficiently the measurement sequence and corrective operations needed for the measurement-based gate teleportation, which will also be explained in detail.

  1. Alternative Anodes for the Electrolytic Reduction of Uranium Dioxide

    NASA Astrophysics Data System (ADS)

    Merwin, Augustus

    Reprocessing of spent nuclear fuel is an essential step in closing the nuclear fuel cycle. In order to consume current stockpiles, ceramic uranium dioxide spent nuclear fuel will be subjected to an electrolytic reduction process. The current reduction process employs a platinum anode and a stainless steel alloy 316 cathode in a molten salt bath consisting of LiCl-2wt% Li 2O and occurs at 700°C. A major shortcoming of the existing process is the degradation of the platinum anode under the severely oxidizing conditions encountered during electrolytic reduction. This work investigates alternative anode materials for the electrolytic reduction of uranium oxide. The high temperature and extreme oxidizing conditions encountered in these studies necessitated a unique set of design constraints on the system. Thus, a customized experimental apparatus was designed and constructed. The electrochemical experiments were performed in an electrochemical reactor placed inside a furnace. This entire setup was housed inside a glove box, in order to maintain an inert atmosphere. This study investigates alternative anode materials through accelerated corrosion testing. Surface morphology was studied using scanning electron microscopy. Surface chemistry was characterized using energy dispersive spectroscopy and Raman spectroscopy. Electrochemical behavior of candidate materials was evaluated using potentiodynamic polarization characteristics. After narrowing the number of candidate electrode materials, ferrous stainless steel alloy 316, nickel based Inconel 718 and elemental tungsten were chosen for further investigation. Of these materials only tungsten was found to be sufficiently stable at the anodic potential required for electrolysis of uranium dioxide in molten salt. The tungsten anode and stainless steel alloy 316 cathode electrode system was studied at the required reduction potential for UO2 with varying lithium oxide concentrations. Electrochemical impedance spectroscopy

  2. Utilizing placebo mechanisms for dose reduction in pharmacotherapy.

    PubMed

    Doering, Bettina K; Rief, Winfried

    2012-03-01

    The knowledge and systematic application of the placebo effect remains limited, although its importance to the treatment of various medical conditions has increasingly been recognized. A possible application of the placebo effect to pharmacotherapy is seen in conditioning processes that aim at a placebo-controlled dose reduction of drugs while maintaining the efficacy of the medical treatment. The pairing of a placebo and a pharmacological agent may achieve satisfactory treatment outcomes in combination with a lower dose of medication. This procedure includes classic and instrumental conditioning processes that involve both conscious and non-conscious information processing. Although recent studies have gathered preliminary evidence for the efficacy of placebo-controlled dose reduction (e.g. in psoriasis and attention deficit hyperactivity disorder [ADHD]), they have also illustrated the difficulties that are inherent to this approach. We critically review previous approaches and discuss designs for clinical trials that seem appropriate to the investigation of conditioned placebo effects in pharmacotherapy. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Hydrogen Plasma Processing of Iron Ore

    NASA Astrophysics Data System (ADS)

    Sabat, Kali Charan; Murphy, Anthony B.

    2017-06-01

    Iron is currently produced by carbothermic reduction of oxide ores. This is a multiple-stage process that requires large-scale equipment and high capital investment, and produces large amounts of CO2. An alternative to carbothermic reduction is reduction using a hydrogen plasma, which comprises vibrationally excited molecular, atomic, and ionic states of hydrogen, all of which can reduce iron oxides, even at low temperatures. Besides the thermodynamic and kinetic advantages of a hydrogen plasma, the byproduct of the reaction is water, which does not pose any environmental problems. A review of the theory and practice of iron ore reduction using a hydrogen plasma is presented. The thermodynamic and kinetic aspects are considered, with molecular, atomic and ionic hydrogen considered separately. The importance of vibrationally excited hydrogen molecules in overcoming the activation energy barriers, and in transferring energy to the iron oxide, is emphasized. Both thermal and nonthermal plasmas are considered. The thermophysical properties of hydrogen and argon-hydrogen plasmas are discussed, and their influence on the constriction and flow in the of arc plasmas is considered. The published R&D on hydrogen plasma reduction of iron oxide is reviewed, with both the reduction of molten iron ore and in-flight reduction of iron ore particles being considered. Finally, the technical and economic feasibility of the process are discussed. It is shown that hydrogen plasma processing requires less energy than carbothermic reduction, mainly because pelletization, sintering, and cokemaking are not required. Moreover, the formation of the greenhouse gas CO2 as a byproduct is avoided. In-flight reduction has the potential for a throughput at least equivalent to the blast furnace process. It is concluded that hydrogen plasma reduction of iron ore is a potentially attractive alternative to standard methods.

  4. Americium recovery from reduction residues

    DOEpatents

    Conner, W.V.; Proctor, S.G.

    1973-12-25

    A process for separation and recovery of americium values from container or bomb'' reduction residues comprising dissolving the residues in a suitable acid, adjusting the hydrogen ion concentration to a desired level by adding a base, precipitating the americium as americium oxalate by adding oxalic acid, digesting the solution, separating the precipitate, and thereafter calcining the americium oxalate precipitate to form americium oxide. (Official Gazette)

  5. Bosch CO2 Reduction System Development

    NASA Technical Reports Server (NTRS)

    Holmes, R. F.; King, C. D.; Keller, E. E.

    1976-01-01

    Development of a Bosch process CO2 reduction unit was continued, and, by means of hardware modifications, the performance was substantially improved. Benefits of the hardware upgrading were demonstrated by extensive unit operation and data acquisition in the laboratory. This work was accomplished on a cold seal configuration of the Bosch unit.

  6. Current Issues in Reductions-in-Force.

    ERIC Educational Resources Information Center

    Caplan, Gerald A.

    The practitioner advising a school board in connection with a reduction in force can appreciate that the board has great flexibility in implementing its decision. As long as the board's actions are not arbitrary, capricious, or pretextual, and they afford minimal due process protections to tenured teachers, the board's decisions will withstand…

  7. Plasma-assisted combustion technology for NOx reduction in industrial burners.

    PubMed

    Lee, Dae Hoon; Kim, Kwan-Tae; Kang, Hee Seok; Song, Young-Hoon; Park, Jae Eon

    2013-10-01

    Stronger regulations on nitrogen oxide (NOx) production have recently promoted the creation of a diverse array of technologies for NOx reduction, particularly within the combustion process, where reduction is least expensive. In this paper, we discuss a new combustion technology that can reduce NOx emissions within industrial burners to single-digit parts per million levels without employing exhaust gas recirculation or other NOx reduction mechanisms. This new technology uses a simple modification of commercial burners, such that they are able to perform plasma-assisted staged combustion without altering the outer configuration of the commercial reference burner. We embedded the first-stage combustor within the head of the commercial reference burner, where it operated as a reformer that could host a partial oxidation process, producing hydrogen-rich reformate or synthesis gas product. The resulting hydrogen-rich flow then ignited and stabilized the combustion flame apart from the burner rim. Ultimately, the enhanced mixing and removal of hot spots with a widened flame area acted as the main mechanisms of NOx reduction. Because this plasma burner acted as a low NOx burner and was able to reduce NOx by more than half compared to the commercial reference burner, this methodology offers important cost-effective possibilities for NOx reduction in industrial applications.

  8. The sequential use of washing and an electrochemical reduction process for the remediation of lead-contaminated soils.

    PubMed

    Demir, Aydeniz; Köleli, Nurcan

    2013-01-01

    A two-step method for the remediation of three different types of lead (Pb)-contaminated soil was evaluated. The first step included soil washing with ethylenediaminetetraacetic acid (EDTA) to remove Pb from soils. The washing experiments were performed with 0.05 M Na2EDTA at 1:10 soil to liquid ratio. Following the washing, Pb removal efficiency from soils ranged within 50-70%. After the soil washing process, Pb2+ ions in the washing solution were reduced electrochemically in a fixed-bed reactor. Lead removal efficiency with the electrochemical reduction at -2.0 V potential ranged within 57-76%. The overall results indicate that this two-step method is an environmentally-friendly and effective technology to remediate Pb-contaminated soils, as well as Pb-contaminated wastewater treatment due to the transformation of toxic Pb2+ ions into a non-hazardous metallic form (Pb(0)).

  9. SU-C-18C-06: Radiation Dose Reduction in Body Interventional Radiology: Clinical Results Utilizing a New Imaging Acquisition and Processing Platform

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kohlbrenner, R; Kolli, KP; Taylor, A

    2014-06-01

    Purpose: To quantify the patient radiation dose reduction achieved during transarterial chemoembolization (TACE) procedures performed in a body interventional radiology suite equipped with the Philips Allura Clarity imaging acquisition and processing platform, compared to TACE procedures performed in the same suite equipped with the Philips Allura Xper platform. Methods: Total fluoroscopy time, cumulative dose area product, and cumulative air kerma were recorded for the first 25 TACE procedures performed to treat hepatocellular carcinoma (HCC) in a Philips body interventional radiology suite equipped with Philips Allura Clarity. The same data were collected for the prior 85 TACE procedures performed to treatmore » HCC in the same suite equipped with Philips Allura Xper. Mean values from these cohorts were compared using two-tailed t tests. Results: Following installation of the Philips Allura Clarity platform, a 42.8% reduction in mean cumulative dose area product (3033.2 versus 1733.6 mGycm∧2, p < 0.0001) and a 31.2% reduction in mean cumulative air kerma (1445.4 versus 994.2 mGy, p < 0.001) was achieved compared to similar procedures performed in the same suite equipped with the Philips Allura Xper platform. Mean total fluoroscopy time was not significantly different between the two cohorts (1679.3 versus 1791.3 seconds, p = 0.41). Conclusion: This study demonstrates a significant patient radiation dose reduction during TACE procedures performed to treat HCC after a body interventional radiology suite was converted to the Philips Allura Clarity platform from the Philips Allura Xper platform. Future work will focus on evaluation of patient dose reduction in a larger cohort of patients across a broader range of procedures and in specific populations, including obese patients and pediatric patients, and comparison of image quality between the two platforms. Funding for this study was provided by Philips Healthcare, with 5% salary support provided to authors K

  10. 36 CFR 218.12 - Timing of authorized hazardous fuel reduction project decision.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE PREDECISIONAL ADMINISTRATIVE REVIEW PROCESSES Predecisional Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests Restoration...

  11. An optimal policy for a single-vendor and a single-buyer integrated system with setup cost reduction and process-quality improvement

    NASA Astrophysics Data System (ADS)

    Shu, Hui; Zhou, Xideng

    2014-05-01

    The single-vendor single-buyer integrated production inventory system has been an object of study for a long time, but little is known about the effect of investing in reducing setup cost reduction and process-quality improvement for an integrated inventory system in which the products are sold with free minimal repair warranty. The purpose of this article is to minimise the integrated cost by optimising simultaneously the number of shipments and the shipment quantity, the setup cost, and the process quality. An efficient algorithm procedure is proposed for determining the optimal decision variables. A numerical example is presented to illustrate the results of the proposed models graphically. Sensitivity analysis of the model with respect to key parameters of the system is carried out. The paper shows that the proposed integrated model can result in significant savings in the integrated cost.

  12. Selective catalyst reduction light-off strategy

    DOEpatents

    Gonze, Eugene V [Pinckney, MI

    2011-10-18

    An emissions control system includes a temperature determination module and an emissions control module. The temperature determination module determines a first temperature of a heater element of a diesel particulate filter (DPF) assembly in an exhaust system and determines a second temperature of a catalyst of the DPF assembly. The emissions control module selectively activates the heater element, selectively initiates a predefined combustion process in an engine based upon the first temperature, and selectively starts a reductant injection process based upon the second temperature.

  13. Enhanced viscous flow drag reduction using acoustic excitation

    NASA Technical Reports Server (NTRS)

    Nagel, Robert T.

    1987-01-01

    Proper acoustic excitation of a single large-eddy break-up device can increase the resulting drag reduction and, after approximately 40 to 50 delta downstream, provide net drag reduction. Precise optimization of the input time delay, amplitude and response threshold is difficult but possible to achieve. Drag reduction is improved with optimized conditions. The possibility of optimized processing strongly suggests a mechanism which involves interaction of the acoustic waves and large eddies at the trailing edge of the large eddy break-up device. Although the mechanism for spreading of this phenomenon is unknown, it is apparent that the drag reduction effect does tend to spread spanwise as the flow convects downstream. The phenomenon is not unique to a particular blade configuration or flow velocity, although all data have been obtained at relatively low Reynolds numbers. The general repeatibility of the results for small configuration changes serves as verification of the phenomenon.

  14. A POLLUTION REDUCTION METHODOLOGY FOR CHEMICAL PROCESS SIMULATORS

    EPA Science Inventory

    A pollution minimization methodology was developed for chemical process design using computer simulation. It is based on a pollution balance that at steady state is used to define a pollution index with units of mass of pollution per mass of products. The pollution balance has be...

  15. 20 CFR 410.540 - Reductions; more than one reduction event.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Reductions; more than one reduction event. 410.540 Section 410.540 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH...; more than one reduction event. If a reduction for receipt of State benefits (see § 410.520) and a...

  16. PM 2.5 and other pollutants -- Reduction of health impacts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Marrack, D.

    The 1990 CAA projected a need to reduce the adverse human health and environmental impacts of exposures to particulates by regulatory reduction of anthropomorphic emissions, solely on the basis of mass reductions, at point and area sources. Ozone reduction would be by reduction of total VOC's and NO{sub x} emissions. The assumptions made about ambient air pollution's biological effects were: The observed health effect was the consequence of a measured single air pollutant treated as independent entities and that their selective reduction would have a specific identifiable health impact reduction. That within the regulated classes PM-10, PM-2.5 and VOC's allmore » components have equal biological impacts. Neither of the assumptions appears to be true. If the assumptions are not true then potentially the same reductions in health impacts could be achieved by reducing the most offensive components at possibly less cost than that required for reducing them all. Ambient pollutants are a complex matrix of dynamically interacting chemical and particle species. Their interactions are going on as they are inhaled. Pollutant measurement systems measure the predominant stable components only. Small amounts of more reactive chemicals and radicals initially present in inhaled air that contacts respiratory tract lining cells and contribute to the bio-effects are lost by the time pollutant analysis is attempted. Identification of some of the specific anthropomorphic emissions components contributing to adverse health effects are known. Methods for reducing their presence in anthropomorphic processes' emissions or their effects will be considered. Their significant role in triggering cardio-pulmonary dysfunction has now been elucidated. Reductions in specific reactive VOC species is another option. The basis for potential actions and their related biological processes will be discussed.« less

  17. The preparation of tantalum powder using a MR-EMR combination process

    NASA Astrophysics Data System (ADS)

    Yoon, Jae Sik; Kim, Byung Il

    2007-04-01

    In the conventional metallothermic reduction (MR) process used to obtain tantalum powder in batch-type operation, it is difficult to control the morphology and location of the tantalum deposits. In contrast, an electronically mediated reaction (EMR) process is capable of overcoming this difficulty. It has the advantage of being a continuous process, but has the disadvantage of a poor reduction yield. A process known as the MR-EMR combination process is able to overcome the shortcomings of the MR and EMR processes. In this study, an MR-EMR combination process is applied to the production of tantalum powder via sodium reduction of K2TaF7. In the MR-EMR combination process, the total charge passed through an external circuit and the average particle size (FSSS) increase as the reduction temperature increases. In addition, the proportion of fine particles (-325 mesh) decreases as the reduction temperature increasess. The tantalum yield improved from 65 to 74% as the reduction temperature increased. Taking into account the charge, impurities, morphology, particle size and yield, a reduction temperature of 1123 K was found to be optimum for the MR-EMR combination process.

  18. 40 CFR 65.154 - Halogen scrubbers and other halogen reduction devices.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 15 2011-07-01 2011-07-01 false Halogen scrubbers and other halogen... Routing to a Fuel Gas System or a Process § 65.154 Halogen scrubbers and other halogen reduction devices. (a) Halogen scrubber and other halogen reduction device equipment and operating requirements. (1) An...

  19. Understanding trends in electrochemical carbon dioxide reduction rates

    DOE PAGES

    Liu, Xinyan; Xiao, Jianping; Peng, Hongjie; ...

    2017-05-22

    Electrochemical carbon dioxide reduction to fuels presents one of the great challenges in chemistry. Herein we present an understanding of trends in electrocatalytic activity for carbon dioxide reduction over different metal catalysts that rationalize a number of experimental observations including the selectivity with respect to the competing hydrogen evolution reaction. We also identify two design criteria for more active catalysts. The understanding is based on density functional theory calculations of activation energies for electrochemical carbon monoxide reduction as a basis for an electrochemical kinetic model of the process. Furthermore, we develop scaling relations relating transition state energies to the carbonmore » monoxide adsorption energy and determine the optimal value of this descriptor to be very close to that of copper.« less

  20. Understanding trends in electrochemical carbon dioxide reduction rates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Xinyan; Xiao, Jianping; Peng, Hongjie

    Electrochemical carbon dioxide reduction to fuels presents one of the great challenges in chemistry. Herein we present an understanding of trends in electrocatalytic activity for carbon dioxide reduction over different metal catalysts that rationalize a number of experimental observations including the selectivity with respect to the competing hydrogen evolution reaction. We also identify two design criteria for more active catalysts. The understanding is based on density functional theory calculations of activation energies for electrochemical carbon monoxide reduction as a basis for an electrochemical kinetic model of the process. Furthermore, we develop scaling relations relating transition state energies to the carbonmore » monoxide adsorption energy and determine the optimal value of this descriptor to be very close to that of copper.« less

  1. 20 CFR 410.540 - Reductions; more than one reduction event.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Reductions; more than one reduction event...; more than one reduction event. If a reduction for receipt of State benefits (see § 410.520) and a... such month is first reduced (but not below zero) by the amount of the State benefits (as determined in...

  2. Optimizing Blocking and Nonblocking Reduction Operations for Multicore Systems: Hierarchical Design and Implementation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gorentla Venkata, Manjunath; Shamis, Pavel; Graham, Richard L

    2013-01-01

    Many scientific simulations, using the Message Passing Interface (MPI) programming model, are sensitive to the performance and scalability of reduction collective operations such as MPI Allreduce and MPI Reduce. These operations are the most widely used abstractions to perform mathematical operations over all processes that are part of the simulation. In this work, we propose a hierarchical design to implement the reduction operations on multicore systems. This design aims to improve the efficiency of reductions by 1) tailoring the algorithms and customizing the implementations for various communication mechanisms in the system 2) providing the ability to configure the depth ofmore » hierarchy to match the system architecture, and 3) providing the ability to independently progress each of this hierarchy. Using this design, we implement MPI Allreduce and MPI Reduce operations (and its nonblocking variants MPI Iallreduce and MPI Ireduce) for all message sizes, and evaluate on multiple architectures including InfiniBand and Cray XT5. We leverage and enhance our existing infrastructure, Cheetah, which is a framework for implementing hierarchical collective operations to implement these reductions. The experimental results show that the Cheetah reduction operations outperform the production-grade MPI implementations such as Open MPI default, Cray MPI, and MVAPICH2, demonstrating its efficiency, flexibility and portability. On Infini- Band systems, with a microbenchmark, a 512-process Cheetah nonblocking Allreduce and Reduce achieves a speedup of 23x and 10x, respectively, compared to the default Open MPI reductions. The blocking variants of the reduction operations also show similar performance benefits. A 512-process nonblocking Cheetah Allreduce achieves a speedup of 3x, compared to the default MVAPICH2 Allreduce implementation. On a Cray XT5 system, a 6144-process Cheetah Allreduce outperforms the Cray MPI by 145%. The evaluation with an application kernel

  3. Sulfur in serpentinized oceanic peridotites: Serpentinization processes and microbial sulfate reduction

    USGS Publications Warehouse

    Alt, J.C.; Shanks, Wayne C.

    1998-01-01

    The mineralogy, contents, and isotopic compositions of sulfur in oceanic serpentinites reflect variations in temperatures and fluid fluxes. Serpentinization of <1 Ma peridotites at Hess Deep occurred at high temperatures (200??-400??C) and low water/rock ratios. Oxidation of ferrous iron to magnetite maintained low fO2and produced a reduced, low-sulfur assemblage including NiFe alloy. Small amounts of sulfate reduction by thermophilic microbes occurred as the system cooled, producing low-??34S sulfide (1.5??? to -23.7???). In contrast, serpentinization of Iberian Margin peridotites occurred at low temperatures (???20??-200??C) and high water/rock ratios. Complete serpentinization and consumption of ferrous iron allowed evolution to higher fO2. Microbial reduction of seawater sulfate resulted in addition of low-??34S sulfide (-15 to -43???) and formation of higher-sulfur assemblages that include valleriite and pyrite. The high SO4/total S ratio of Hess Deep serpentinites (0.89) results in an increase of total sulfur and high ??34S of total sulfur (mean ??? 8???). In contrast, Iberian Margin serpentinites gained large amounts of 34S-poor sulfide (mean total S = 3800 ppm), and the high sulfide/total S ratio (0.61) results in a net decrease in ??34S of total sulfur (mean ??? -5???). Thus serpentinization is a net sink for seawater sulfur, but the amount fixed and its isotopic composition vary significantly. Serpentinization may result in uptake of 0.4-14 ?? 1012 g S yr-1 from the oceans, comparable to isotopic exchange in mafic rocks of seafloor hydrothermal systems and approaching global fluxes of riverine sulfate input and sedimentary sulfide output.

  4. Reduction process of nitroxyl spin probes used in Overhauser-enhanced magnetic resonance imaging: An ESR study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Meenakumari, V.; Premkumar, S.; Benial, A. Milton Franklin, E-mail: miltonfranklin@yahoo.com

    The Electron spin resonance studies on the reduction process of nitroxyl spin probes were carried out for 1mM {sup 14}N- labeled nitroxyl radicals in pure water and 1 mM concentration of ascorbic acid as a function of time. The electron spin resonance parameters, such as line width, hyperfine coupling constant, g-factor, signal intensity ratio and rotational correlation time were estimated. The 3-carbamoyl-PROXYL radical has narrowest line width and fast tumbling motion compared with 3-carboxy-PROXYL, 4-methoxy-TEMPO, and 4-acetamido-TEMPO radicals. The half life time and decay rate were estimated for 1mM concentration of {sup 14}N- labeled nitroxyl radicals in 1 mM concentration ofmore » ascorbic acid. From the results, the 3-carbamoyl-PROXYL has long half life time and high stability compared with 3-carboxy-PROXYL, 4-methoxy-TEMPO and 4-acetamido-TEMPO radicals. Therefore, this study reveals that the 3-carbamoyl-PROXYL radical can act as a good redox sensitive spin probe for Overhauser-enhanced Magnetic Resonance Imaging.« less

  5. Reduction process of nitroxyl spin probes used in Overhauser-enhanced magnetic resonance imaging: An ESR study

    NASA Astrophysics Data System (ADS)

    Meenakumari, V.; Jawahar, A.; Premkumar, S.; Benial, A. Milton Franklin

    2016-05-01

    The Electron spin resonance studies on the reduction process of nitroxyl spin probes were carried out for 1mM 14N- labeled nitroxyl radicals in pure water and 1 mM concentration of ascorbic acid as a function of time. The electron spin resonance parameters, such as line width, hyperfine coupling constant, g-factor, signal intensity ratio and rotational correlation time were estimated. The 3-carbamoyl-PROXYL radical has narrowest line width and fast tumbling motion compared with 3-carboxy-PROXYL, 4-methoxy-TEMPO, and 4-acetamido-TEMPO radicals. The half life time and decay rate were estimated for 1mM concentration of 14N- labeled nitroxyl radicals in 1 mM concentration of ascorbic acid. From the results, the 3-carbamoyl-PROXYL has long half life time and high stability compared with 3-carboxy-PROXYL, 4-methoxy-TEMPO and 4-acetamido-TEMPO radicals. Therefore, this study reveals that the 3-carbamoyl-PROXYL radical can act as a good redox sensitive spin probe for Overhauser-enhanced Magnetic Resonance Imaging.

  6. Effect of phosphorus addition on the reductive transformation of pentachlorophenol (PCP) and iron reduction with microorganism involvement.

    PubMed

    Wang, Yongkui; Liu, Xianli; Huang, Jiexun; Xiao, Wensheng; Zhang, Jiaquan; Yin, Chunqin

    2017-10-01

    The transformation of phosphorus added to the soil environment has been proven to be influenced by the Fe biochemical process, which thereby may affect the transformation of organic chlorinated contaminants. However, the amount of related literatures regarding this topic is limited. This study aimed to determine the effects of phosphorus addition on pentachlorophenol (PCP) anaerobic transformation, iron reduction, and paddy soil microbial community structure. Results showed that the transformation of phosphorus, iron, and PCP were closely related to the microorganisms. Moreover, phosphorus addition significantly influenced PCP transformation and iron reduction, which promoted and inhibited these processes at low and high concentrations, respectively. Both the maximum reaction rate of PCP transformation and the maximum Fe(II) amount produced were obtained at 1 mmol/L phosphorus concentration. Among the various phosphorus species, dissolved P and NaOH-P considerably changed, whereas only slight changes were observed for the remaining phosphorus species. Microbial community structure analysis demonstrated that adding low concentration of phosphorus promoted the growth of Clostridium bowmanii, Clostridium hungatei, and Clostridium intestinale and Pseudomonas veronii. By contrast, high-concentration phosphorus inhibited growth of these microorganisms, similar to the curves of PCP transformation and iron reduction. These observations indicated that Clostridium and P. veronii, especially Clostridium, played a vital role in the transformation of related substances in the system. All these findings may serve as a reference for the complicated reactions among the multiple components of soils.

  7. The Process of Fear Reduction Through Systematic Desensitization

    ERIC Educational Resources Information Center

    Schroeder, Harold E.; Rich, Alex R.

    1976-01-01

    This study investigated the process of fear change during a course of systematic desensitization therapy. Behavioral, subjective, and physiological measures of fear were taken following each of eight therapy sessions. Changes in one fear system did not appear to be primary in initiating changes in the other fear systems. (Author)

  8. Mercury Reduction and Removal from High Level Waste at the Defense Waste Processing Facility - 12511

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Behrouzi, Aria; Zamecnik, Jack

    2012-07-01

    The Defense Waste Processing Facility processes legacy nuclear waste generated at the Savannah River Site during production of enriched uranium and plutonium required by the Cold War. The nuclear waste is first treated via a complex sequence of controlled chemical reactions and then vitrified into a borosilicate glass form and poured into stainless steel canisters. Converting the nuclear waste into borosilicate glass is a safe, effective way to reduce the volume of the waste and stabilize the radionuclides. One of the constituents in the nuclear waste is mercury, which is present because it served as a catalyst in the dissolutionmore » of uranium-aluminum alloy fuel rods. At high temperatures mercury is corrosive to off-gas equipment, this poses a major challenge to the overall vitrification process in separating mercury from the waste stream prior to feeding the high temperature melter. Mercury is currently removed during the chemical process via formic acid reduction followed by steam stripping, which allows elemental mercury to be evaporated with the water vapor generated during boiling. The vapors are then condensed and sent to a hold tank where mercury coalesces and is recovered in the tank's sump via gravity settling. Next, mercury is transferred from the tank sump to a purification cell where it is washed with water and nitric acid and removed from the facility. Throughout the chemical processing cell, compounds of mercury exist in the sludge, condensate, and off-gas; all of which present unique challenges. Mercury removal from sludge waste being fed to the DWPF melter is required to avoid exhausting it to the environment or any negative impacts to the Melter Off-Gas system. The mercury concentration must be reduced to a level of 0.8 wt% or less before being introduced to the melter. Even though this is being successfully accomplished, the material balances accounting for incoming and collected mercury are not equal. In addition, mercury has not been

  9. Comparative intelligibility investigation of single-channel noise-reduction algorithms for Chinese, Japanese, and English.

    PubMed

    Li, Junfeng; Yang, Lin; Zhang, Jianping; Yan, Yonghong; Hu, Yi; Akagi, Masato; Loizou, Philipos C

    2011-05-01

    A large number of single-channel noise-reduction algorithms have been proposed based largely on mathematical principles. Most of these algorithms, however, have been evaluated with English speech. Given the different perceptual cues used by native listeners of different languages including tonal languages, it is of interest to examine whether there are any language effects when the same noise-reduction algorithm is used to process noisy speech in different languages. A comparative evaluation and investigation is taken in this study of various single-channel noise-reduction algorithms applied to noisy speech taken from three languages: Chinese, Japanese, and English. Clean speech signals (Chinese words and Japanese words) were first corrupted by three types of noise at two signal-to-noise ratios and then processed by five single-channel noise-reduction algorithms. The processed signals were finally presented to normal-hearing listeners for recognition. Intelligibility evaluation showed that the majority of noise-reduction algorithms did not improve speech intelligibility. Consistent with a previous study with the English language, the Wiener filtering algorithm produced small, but statistically significant, improvements in intelligibility for car and white noise conditions. Significant differences between the performances of noise-reduction algorithms across the three languages were observed.

  10. Oxygen Reduction Reaction for Generating H2 O2 through a Piezo-Catalytic Process over Bismuth Oxychloride.

    PubMed

    Shao, Dengkui; Zhang, Ling; Sun, Songmei; Wang, Wenzhong

    2018-02-09

    Oxygen reduction reaction (ORR) for generating H 2 O 2 through green pathways have gained much attention in recent years. Herein, we introduce a piezo-catalytic approach to obtain H 2 O 2 over bismuth oxychloride (BiOCl) through an ORR pathway. The piezoelectric response of BiOCl was directly characterized by piezoresponse force microscopy (PFM). The BiOCl exhibits efficient catalytic performance for generating H 2 O 2 (28 μmol h -1 ) only from O 2 and H 2 O, which is above the average level of H 2 O 2 produced by solar-to-chemical processes. A piezo-catalytic mechanism was proposed: with ultrasonic waves, an alternating electric field will be generated over BiOCl, which can drive charge carriers (electrons) to interact with O 2 and H 2 O, then to form H 2 O 2 . © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Production of Solar-grade Silicon by Halidothermic Reduction of Silicon Tetrachloride

    NASA Astrophysics Data System (ADS)

    Yasuda, Kouji; Saegusa, Kunio; Okabe, Toru H.

    2011-02-01

    To develop a new production process for solar-grade Si, a fundamental study on halidothermic reduction based on the subhalide reduction of SiCl4 by Al subchloride reductant was carried out at 1273 K (1000 °C). Aluminum subchloride reductant was produced by reacting AlCl3 vapor with metallic Al. Silicon tetrachloride was reduced to Si in a gas-phase reaction by vapors of Al subchloride reductant. Silicon deposits produced in the halidothermic reduction were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray fluorescence (XRF). The Al content in the Si deposits was no more than 0.5 at pct. The Si deposits have a fibrous or hexagonal columnar morphology with diameters ranging from 100 nm to several tens of microns. The reaction was discussed by comparison with the results of the conventional aluminothermic reduction of SiCl4. Moreover, the halidothermic reduction reactions were analyzed from thermodynamical viewpoints. This study demonstrates the feasibility of a halidothermic reduction for producing solar-grade Si with high productivity.

  12. 36 CFR 218.3 - Authorized hazardous fuel reduction projects subject to objection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE PREDECISIONAL ADMINISTRATIVE REVIEW PROCESSES Predecisional Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests Restoration..., the objection process of this part applies to both the plan amendment and the project. ...

  13. 42 CFR 433.120 - Procedures for reduction of FFP after reapproval review.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Claims Processing and Information Retrieval Systems § 433.120 Procedures for reduction of FFP after... significance of the unsatisfactory conditions in overall mechanized claims processing and information retrieval...

  14. Calculation of energy recovery and greenhouse gas emission reduction from palm oil mill effluent treatment by an anaerobic granular-sludge process.

    PubMed

    Show, K Y; Ng, C A; Faiza, A R; Wong, L P; Wong, L Y

    2011-01-01

    Conventional aerobic and low-rate anaerobic processes such as pond and open-tank systems have been widely used in wastewater treatment. In order to improve treatment efficacy and to avoid greenhouse gas emissions, conventional treatment can be upgraded to a high performance anaerobic granular-sludge system. The anaerobic granular-sludge systems are designed to capture the biogas produced, rendering a potential for claims of carbon credits under the Kyoto Protocol for reducing emissions of greenhouse gases. Certified Emission Reductions (CERs) would be issued, which can be exchanged between businesses or bought and sold in international markets at the prevailing market prices. As the advanced anaerobic granular systems are capable of handling high organic loadings concomitant with high strength wastewater and short hydraulic retention time, they render more carbon credits than other conventional anaerobic systems. In addition to efficient waste degradation, the carbon credits can be used to generate revenue and to finance the project. This paper presents a scenario on emission avoidance based on a methane recovery and utilization project. An example analysis on emission reduction and an overview of the global emission market are also outlined.

  15. Reduction redux.

    PubMed

    Shapiro, Lawrence

    2018-04-01

    Putnam's criticisms of the identity theory attack a straw man. Fodor's criticisms of reduction attack a straw man. Properly interpreted, Nagel offered a conception of reduction that captures everything a physicalist could want. I update Nagel, introducing the idea of overlap, and show why multiple realization poses no challenge to reduction so construed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Lexical Predictability During Natural Reading: Effects of Surprisal and Entropy Reduction.

    PubMed

    Lowder, Matthew W; Choi, Wonil; Ferreira, Fernanda; Henderson, John M

    2018-06-01

    What are the effects of word-by-word predictability on sentence processing times during the natural reading of a text? Although information complexity metrics such as surprisal and entropy reduction have been useful in addressing this question, these metrics tend to be estimated using computational language models, which require some degree of commitment to a particular theory of language processing. Taking a different approach, this study implemented a large-scale cumulative cloze task to collect word-by-word predictability data for 40 passages and compute surprisal and entropy reduction values in a theory-neutral manner. A separate group of participants read the same texts while their eye movements were recorded. Results showed that increases in surprisal and entropy reduction were both associated with increases in reading times. Furthermore, these effects did not depend on the global difficulty of the text. The findings suggest that surprisal and entropy reduction independently contribute to variation in reading times, as these metrics seem to capture different aspects of lexical predictability. Copyright © 2018 Cognitive Science Society, Inc.

  17. ENVIRONMENTAL CHARACTERISTICS AFFECTING REDUCTIVE TRANSFORMATION OF ORGANIC POLLUTANTS IN ANOXIC SEDIMENTS

    EPA Science Inventory

    Reductive transformations are important processes for determining the fate of organic pollutants in anoxic environments. These processes are most often microbially mediated by both direct and indirect means. For example, specific bacteria transform organic pollutants directly as ...

  18. Six steps to a successful dose-reduction strategy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bennett, M.

    1995-03-01

    The increased importance of demonstrating achievement of the ALARA principle has helped produce a proliferation of dose-reduction ideas. Across a company there may be many dose-reduction items being pursued in a variety of areas. However, companies have a limited amount of resource and, therefore, to ensure funding is directed to those items which will produce the most benefit and that all areas apply a common policy, requires the presence of a dose-reduction strategy. Six steps were identified in formulating the dose-reduction strategy for Rolls-Royce and Associates (RRA): (1) collating the ideas; (2) quantitatively evaluating them on a common basis; (3)more » prioritizing the ideas in terms of cost benefit, (4) implementation of the highest priority items; (5) monitoring their success; (6) periodically reviewing the strategy. Inherent in producing the dose-reduction strategy has been a comprehensive dose database and the RRA-developed dose management computer code DOMAIN, which allows prediction of dose rates and dose. The database enabled high task dose items to be identified, assisted in evaluating dose benefits, and monitored dose trends once items had been implemented. The DOMAIN code was used both in quantifying some of the project dose benefits and its results, such as dose contours, used in some of the dose-reduction items themselves. In all, over fifty dose-reduction items were evaluated in the strategy process and the items which will give greatest benefit are being implemented. The strategy has been successful in giving renewed impetus and direction to dose-reduction management.« less

  19. Numerical Modeling of Arsenic Mobility during Reductive Iron-Mineral Transformations.

    PubMed

    Rawson, Joey; Prommer, Henning; Siade, Adam; Carr, Jackson; Berg, Michael; Davis, James A; Fendorf, Scott

    2016-03-01

    Millions of individuals worldwide are chronically exposed to hazardous concentrations of arsenic from contaminated drinking water. Despite massive efforts toward understanding the extent and underlying geochemical processes of the problem, numerical modeling and reliable predictions of future arsenic behavior remain a significant challenge. One of the key knowledge gaps concerns a refined understanding of the mechanisms that underlie arsenic mobilization, particularly under the onset of anaerobic conditions, and the quantification of the factors that affect this process. In this study, we focus on the development and testing of appropriate conceptual and numerical model approaches to represent and quantify the reductive dissolution of iron oxides, the concomitant release of sorbed arsenic, and the role of iron-mineral transformations. The initial model development in this study was guided by data and hypothesized processes from a previously reported,1 well-controlled column experiment in which arsenic desorption from ferrihydrite coated sands by variable loads of organic carbon was investigated. Using the measured data as constraints, we provide a quantitative interpretation of the processes controlling arsenic mobility during the microbial reductive transformation of iron oxides. Our analysis suggests that the observed arsenic behavior is primarily controlled by a combination of reductive dissolution of ferrihydrite, arsenic incorporation into or co-precipitation with freshly transformed iron minerals, and partial arsenic redox transformations.

  20. Perchlorate reduction by autotrophic bacteria in the presence of zero-valent iron.

    PubMed

    Yu, Xueyuan; Amrhein, Christopher; Deshusses, Marc A; Matsumoto, Mark R

    2006-02-15

    A series of batch experiments were performed to study the combination of zero-valent iron (ZVI) with perchlorate-reducing microorganisms (PRMs) to remove perchlorate from groundwater. In this method, H2 produced during the process of iron corrosion by water is used by PRMs as an electron donor to reduce perchlorate to chloride. Perchlorate degradation rates followed Monod kinetics, with a normalized maximum utilization rate (rmax) of 9200 microg g(-1) (dry wt) h(-1) and a half-velocity constant (Ks) of 8900 microg L(-1). The overall rate of perchlorate reduction was affected by the biomass density within the system. An increase in the OD600 from 0.025 to 0.08 led to a corresponding 4-fold increase of perchlorate reduction rate. PRM adaptation to the local environment and initiation of perchlorate reduction was rapid under neutral pH conditions. At the initial OD600 of 0.015, perchlorate reduction followed pseudo-first-order reaction rates with constants of 0.059 and 0.033 h(-1) at initial pH 7 and 8, respectively. Once perchlorate reduction was established, the bioreductive process was insensitive to the increases of pH from near neutral to 9.0. In the presence of nitrate, perchlorate reduction rate was reduced, but not inhibited completely.

  1. 36 CFR 218.4 - Authorized hazardous fuel reduction projects not subject to objection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE PREDECISIONAL ADMINISTRATIVE REVIEW PROCESSES Predecisional Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests Restoration...

  2. ORAC-DR: Astronomy data reduction pipeline

    NASA Astrophysics Data System (ADS)

    Jenness, Tim; Economou, Frossie; Cavanagh, Brad; Currie, Malcolm J.; Gibb, Andy

    2013-10-01

    ORAC-DR is a generic data reduction pipeline infrastructure; it includes specific data processing recipes for a number of instruments. It is used at the James Clerk Maxwell Telescope, United Kingdom Infrared Telescope, AAT, and LCOGT. This pipeline runs at the JCMT Science Archive hosted by CADC to generate near-publication quality data products; the code has been in use since 1998.

  3. Structural, textural and sensory impact of sodium reduction on long fermented pizza.

    PubMed

    Bernklau, Isabelle; Neußer, Christian; Moroni, Alice V; Gysler, Christof; Spagnolello, Alessandro; Chung, Wookyung; Jekle, Mario; Becker, Thomas

    2017-11-01

    The aim of this study was to elucidate the microstructural, textural, and sensory impact of sodium reduction and its partial replacement by potassium chloride in pizza dough and crusts prepared by a traditional long fermentation process. For the first time, macrostructural changes in texture were elucidated and quantified by a novel protein network analysis. The fermentation process exerted a strengthening effect in the doughs, allowing to reduce sodium up to 25% without any negative impact on texture. Sodium reduction by 15% did not cause any significant textural changes in pizza crusts and partial replacement by KCl resulted in a strengthened dough and firmer pizza crust. The use of toppings masked the effect of lowering the sodium content, allowing to increase the reduction level from 15% to 35%. A reduction of NaCl by 25% with an addition of KCl achieved high acceptance in the sensory evaluation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Ni-Catalyzed Carbon-Carbon Bond-Forming Reductive Amination.

    PubMed

    Heinz, Christoph; Lutz, J Patrick; Simmons, Eric M; Miller, Michael M; Ewing, William R; Doyle, Abigail G

    2018-02-14

    This report describes a three-component, Ni-catalyzed reductive coupling that enables the convergent synthesis of tertiary benzhydryl amines, which are challenging to access by traditional reductive amination methodologies. The reaction makes use of iminium ions generated in situ from the condensation of secondary N-trimethylsilyl amines with benzaldehydes, and these species undergo reaction with several distinct classes of organic electrophiles. The synthetic value of this process is demonstrated by a single-step synthesis of antimigraine drug flunarizine (Sibelium) and high yielding derivatization of paroxetine (Paxil) and metoprolol (Lopressor). Mechanistic investigations support a sequential oxidative addition mechanism rather than a pathway proceeding via α-amino radical formation. Accordingly, application of catalytic conditions to an intramolecular reductive coupling is demonstrated for the synthesis of endo- and exocyclic benzhydryl amines.

  5. Economics of polysilicon processes

    NASA Technical Reports Server (NTRS)

    Yaws, C. L.; Li, K. Y.; Chou, S. M.

    1986-01-01

    Techniques are being developed to provide lower cost polysilicon material for solar cells. Existing technology which normally provides semiconductor industry polysilicon material is undergoing changes and also being used to provide polysilicon material for solar cells. Economics of new and existing technologies are presented for producing polysilicon. The economics are primarily based on the preliminary process design of a plant producing 1,000 metric tons/year of silicon. The polysilicon processes include: Siemen's process (hydrogen reduction of trichlorosilane); Union Carbide process (silane decomposition); and Hemlock Semiconductor process (hydrogen reduction of dichlorosilane). The economics include cost estimates of capital investment and product cost to produce polysilicon via the technology. Sensitivity analysis results are also presented to disclose the effect of major paramentes such as utilities, labor, raw materials and capital investment.

  6. Body hair counts during hair length reduction procedures: a comparative study between Computer Assisted Image Analysis after Manual Processing (CAIAMP) and Trichoscan(™).

    PubMed

    Van Neste, D J J

    2015-08-01

    To compare two measurement methods for body hair. Calibration of computer assisted image analysis after manual processing (CAIAMP) showed variation <4% for thickness and <2.3% for densities. Images from 6 body sites with 'good natural contrast between hair and skin' were taken before hair dye, after hair dye or after hair length reduction without hair extraction or destruction. Data in the same targets were compared with Trichoscan(™) quoted for 'unambiguous evaluation of the hair growth after shaving'. CAIAMP detected a total of 337 hair and showed no statistically significant differences with the three procedures confirming 'good natural contrast between hair and skin' and that reduction methods did not affect hair counts. While CAIAMP found a mean number of 19 thick hair (≥30 μm) before dye, 18 after dye and 20 after hair reduction, Trichoscan(™) found in the same sites respectively 44, 73 and 61. Trichoscan(™) generated counts differed statistically significantly from CAIAMP-data. Automated analyses were considered un-specifically influenced by hair medulla and natural or artificial skin background. Quality control including all steps of human intervention and measurement technology are mandatory for body hair measurements during experimental or clinical trials on body hair grooming, shaving or removal. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Real-time speckle reduction in optical coherence tomography using the dual window method

    PubMed Central

    Zhao, Yang; Chu, Kengyeh K.; Eldridge, Will J.; Jelly, Evan T.; Crose, Michael; Wax, Adam

    2018-01-01

    Speckle is an intrinsic noise of interferometric signals which reduces contrast and degrades the quality of optical coherence tomography (OCT) images. Here, we present a frequency compounding speckle reduction technique using the dual window (DW) method. Using the DW method, speckle noise is reduced without the need to acquire multiple frames. A ~25% improvement in the contrast-to-noise ratio (CNR) was achieved using the DW speckle reduction method with only minimal loss (~17%) in axial resolution. We also demonstrate that real-time speckle reduction can be achieved at a B-scan rate of ~21 frames per second using a graphic processing unit (GPU). The DW speckle reduction technique can work on any existing OCT instrument without further system modification or extra components. This makes it applicable both in real-time imaging systems and during post-processing. PMID:29552398

  8. Real-time speckle reduction in optical coherence tomography using the dual window method.

    PubMed

    Zhao, Yang; Chu, Kengyeh K; Eldridge, Will J; Jelly, Evan T; Crose, Michael; Wax, Adam

    2018-02-01

    Speckle is an intrinsic noise of interferometric signals which reduces contrast and degrades the quality of optical coherence tomography (OCT) images. Here, we present a frequency compounding speckle reduction technique using the dual window (DW) method. Using the DW method, speckle noise is reduced without the need to acquire multiple frames. A ~25% improvement in the contrast-to-noise ratio (CNR) was achieved using the DW speckle reduction method with only minimal loss (~17%) in axial resolution. We also demonstrate that real-time speckle reduction can be achieved at a B-scan rate of ~21 frames per second using a graphic processing unit (GPU). The DW speckle reduction technique can work on any existing OCT instrument without further system modification or extra components. This makes it applicable both in real-time imaging systems and during post-processing.

  9. Environmental Optimization Using the WAste Reduction Algorithm (WAR)

    EPA Science Inventory

    Traditionally chemical process designs were optimized using purely economic measures such as rate of return. EPA scientists developed the WAste Reduction algorithm (WAR) so that environmental impacts of designs could easily be evaluated. The goal of WAR is to reduce environme...

  10. DESIGNING SUSTAINABLE PROCESSES WITH SIMULATION: THE WASTE REDUCTION (WAR) ALGORITHM

    EPA Science Inventory

    The WAR Algorithm, a methodology for determining the potential environmental impact (PEI) of a chemical process, is presented with modifications that account for the PEI of the energy consumed within that process. From this theory, four PEI indexes are used to evaluate the envir...

  11. Effects of processing and cooking on the reduction of dinotefuran concentration in Japanese rice samples.

    PubMed

    Watanabe, Minae; Ueyama, Jun; Ueno, Eiji; Ueda, Yuko; Oda, Masaya; Umemura, Yuko; Tanahashi, Takashi; Ikai, Yoshitomo; Saito, Isao

    2018-05-23

    Dinotefuran is an insecticide belonging to the neonicotinoid class, which is frequently used to control pests in paddy rice owing to its permeability and effectiveness against sucking insects. Since 2002, this insecticide has been commercially available in Japan, and has become controversial due to its high detection frequency in brown rice for primary consumption. In this study, the effects of processing and cooking on the reduction of dinotefuran residues in commercially available brown rice were investigated. Boiled rice is difficult to homogenise and extract with acetonitrile. Using pre-freezing and cryogenic milling with powdered dry ice, dinotefuran in boiled rice was extracted well. A measurement method comprising sample preparation (acetonitrile extraction, gel permeation chromatography, and SPE) and detection with anLC-MS/MS system was used. In 10 out of 25 commercial brown rice samples, dinotefuran was detected at a concentration of 0.04 μg/g (mean), which was more than the limit of quantitation of 0.01 μg/g. The dinotefuran levels were significantly less than the MRL of 2 μg/g in Japan. Even after polishing, washing, and boiling, dinotefuran was detected in 10 brown rice samples, with mean residue levels of 74.7%, 60.8%, and 39.6%, respectively, of the original concentration in brown rice. Based on these data, the processing factor of dinotefuran in boiled rice has been estimated to be approximately 0.4. Dinotefuran residues were reduced in the boiled rice, but less so than other pesticides. Although the maximum daily intake of dinotefuran in boiled rice was 0.0065 mg/person/day, its percent ratio to the ADI of dinotefuran in Japan was less than 0.05%. These results suggest that the daily intake of dinotefuran from rice might not be a critical problem at present, in spite of its relatively high detection frequency in boiled rice.

  12. Processing lunar soils for oxygen and other materials

    NASA Technical Reports Server (NTRS)

    Knudsen, Christian W.; Gibson, Michael A.

    1992-01-01

    Two types of lunar materials are excellent candidates for lunar oxygen production: ilmenite and silicates such as anorthite. Both are lunar surface minable, occurring in soils, breccias, and basalts. Because silicates are considerably more abundant than ilmenite, they may be preferred as source materials. Depending on the processing method chosen for oxygen production and the feedstock material, various useful metals and bulk materials can be produced as byproducts. Available processing techniques include hydrogen reduction of ilmenite and electrochemical and chemical reductions of silicates. Processes in these categories are generally in preliminary development stages and need significant research and development support to carry them to practical deployment, particularly as a lunar-based operation. The goal of beginning lunar processing operations by 2010 requires that planning and research and development emphasize the simplest processing schemes. However, more complex schemes that now appear to present difficult technical challenges may offer more valuable metal byproducts later. While they require more time and effort to perfect, the more complex or difficult schemes may provide important processing and product improvements with which to extend and elaborate the initial lunar processing facilities. A balanced R&D program should take this into account. The following topics are discussed: (1) ilmenite--semi-continuous process; (2) ilmenite--continuous fluid-bed reduction; (3) utilization of spent ilmenite to produce bulk materials; (4) silicates--electrochemical reduction; and (5) silicates--chemical reduction.

  13. Toxicity reduction in industrial effluents

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1990-01-01

    Wastewater treatment technology is undergoing a profound transformation as a result of the fundamental changes in regulations and permit requirements. Established design procedures and criteria which have served the industry well for decades are no longer useful. Toxicity reduction requirements have forced reconsideration of design standards and caused practicing environmental engineers to seek additional training in the biological sciences. Formal academic programs have not traditionally provided the cross-training between biologists and engineers which is necessary to address these issues. This book describes not only the process of identifying the toxicity problem, but also the treatment technologies which are applicable tomore » reduction or elimination of toxicity. The information provided in this book is a compilation of the experience of ECK-ENFELDER INC. in serving the environmental needs of major industry, and the experience of the individual contributors in research and consultations.« less

  14. Dynamic processes occurring at the Cr IIIaq-manganite (γ-MnOOH) interface: simultaneous adsorption, microprecipitation, oxidation/reduction, and dissolution

    NASA Astrophysics Data System (ADS)

    Weaver, Robert M.; Hochella, Michael F.; Ilton, Eugene S.

    2002-12-01

    The complex interaction between Cr IIIaq and manganite (γ-MnOOH) was systematically studied at room temperature over a pH range of 3 to 6, and within a concentration range of 10 -4 to 10 -2 M CrOH 2+aq. Solution compositional changes during batch reactions were characterized by inductively coupled plasma spectroscopy and ultraviolet-visible spectrophotometry. The manganites were characterized before and after reaction with X-ray photoelectron spectroscopy, scanning electron microscopy (SEM), high-resolution field-emission SEM, and energy-dispersive spectroscopy analysis. Fluid-cell atomic force microscopy was used to follow these metal-mineral interactions in situ. The reactions are characterized by (1) sorption of Cr III and the surface-catalyzed microprecipitation of Cr III-hydroxy hydrate on manganite surfaces, (2) the acidic dissolution of the manganite, and (3) the simultaneous reductive dissolution of manganite coupled with the oxidation of Cr IIIaq to highly toxic Cr VIaq. Cr III-hydroxy hydrate was shown to precipitate on the manganite surface while still undersaturated in bulk solution. The rate of manganite dissolution increased with decreasing pH due both to acid-promoted and Mn-reduction-promoted dissolution. Cr oxidation also increased in the lower pH range, this as a result of its direct redox coupling with Mn reduction. Neither Mn II nor Cr VI were ever detected on manganite surfaces, even at the maximum rate of their generation. At the highest pHs of this study, Cr IIIaq was effectively removed from solution to form Cr III-hydroxy hydrate on manganite surfaces and in the bulk solution, and manganite dissolution and Cr VIaq generation were minimized. All interface reactions described above were heterogeneous across the manganite surfaces. This heterogeneity is a direct result of the heterogeneous semiconducting nature of natural manganite crystals and is also an expression of the proximity effect, whereby redox processes on semiconducting surfaces

  15. Short mechanical biological treatment of municipal solid waste allows landfill impact reduction saving waste energy content.

    PubMed

    Scaglia, Barbara; Salati, Silvia; Di Gregorio, Alessandra; Carrera, Alberto; Tambone, Fulvia; Adani, Fabrizio

    2013-09-01

    The aim of this work was to evaluate the effects of full scale MBT process (28 d) in removing inhibition condition for successive biogas (ABP) production in landfill and in reducing total waste impact. For this purpose the organic fraction of MSW was treated in a full-scale MBT plant and successively incubated vs. untreated waste, in simulated landfills for one year. Results showed that untreated landfilled-waste gave a total ABP reduction that was null. On the contrary MBT process reduced ABP of 44%, but successive incubation for one year in landfill gave a total ABP reduction of 86%. This ABP reduction corresponded to a MBT process of 22 weeks length, according to the predictive regression developed for ABP reduction vs. MBT-time. Therefore short MBT allowed reducing landfill impact, preserving energy content (ABP) to be produced successively by bioreactor technology since pre-treatment avoided process inhibition because of partial waste biostabilization. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Source reduction for prevention of methylene chloride hazards: cases from four industrial sectors.

    PubMed

    Roelofs, Cora R; Ellenbecker, Michael J

    2003-07-21

    Source reduction, defined as chemical, equipment and process changes that intervene in an industrial process to eliminate or reduce hazards, has not figured as a front-line strategy for the protection of workers' health. Such initiatives are popular for environmental protection, but their feasibility and effectiveness as an industrial hygiene approach have not been well described. We investigated four cases of source reduction as a hazard prevention strategy in Massachusetts companies that had used methylene chloride, an occupational carcinogen, for cleaning and adhesive thinning. Three cases were retrospective and one was prospective, where the researchers assisted with the source reduction process change. Data were collected using qualitative research methods, including in-depth interviews and site visits. Motivated by environmental restrictions, a new worker health standard, and opportunity for productivity improvements, three companies eliminated their use of methylene chloride by utilizing available technologies and drop-in substitutes. Aided by technical assistance from the investigators, a fourth case dramatically reduced its use of methylene chloride via process and chemistry changes. While the companies' evaluations of potential work environment impacts of substitutes were not extensive, and in two cases new potential hazards were introduced, the overall impact of the source reduction strategy was deemed beneficial, both from a worker health and a production standpoint. The findings from these four cases suggest that source reduction should be considered potentially feasible and effective for reducing or eliminating the potential hazards of methylene chloride exposure. Especially when faced with a hazard that is both an environmental and worker health concern, companies may chose to change their processes rather than rely on local exhaust ventilation equipment or personal protective equipment that might not be as effective, might transfer risk and/or not

  17. Source reduction for prevention of methylene chloride hazards: cases from four industrial sectors

    PubMed Central

    Roelofs, Cora R; Ellenbecker, Michael J

    2003-01-01

    Background Source reduction, defined as chemical, equipment and process changes that intervene in an industrial process to eliminate or reduce hazards, has not figured as a front-line strategy for the protection of workers' health. Such initiatives are popular for environmental protection, but their feasibility and effectiveness as an industrial hygiene approach have not been well described. Methods We investigated four cases of source reduction as a hazard prevention strategy in Massachusetts companies that had used methylene chloride, an occupational carcinogen, for cleaning and adhesive thinning. Three cases were retrospective and one was prospective, where the researchers assisted with the source reduction process change. Data were collected using qualitative research methods, including in-depth interviews and site visits. Results Motivated by environmental restrictions, a new worker health standard, and opportunity for productivity improvements, three companies eliminated their use of methylene chloride by utilizing available technologies and drop-in substitutes. Aided by technical assistance from the investigators, a fourth case dramatically reduced its use of methylene chloride via process and chemistry changes. While the companies' evaluations of potential work environment impacts of substitutes were not extensive, and in two cases new potential hazards were introduced, the overall impact of the source reduction strategy was deemed beneficial, both from a worker health and a production standpoint. Conclusion The findings from these four cases suggest that source reduction should be considered potentially feasible and effective for reducing or eliminating the potential hazards of methylene chloride exposure. Especially when faced with a hazard that is both an environmental and worker health concern, companies may chose to change their processes rather than rely on local exhaust ventilation equipment or personal protective equipment that might not be as

  18. Development and evaluation of thermal model reduction algorithms for spacecraft

    NASA Astrophysics Data System (ADS)

    Deiml, Michael; Suderland, Martin; Reiss, Philipp; Czupalla, Markus

    2015-05-01

    This paper is concerned with the topic of the reduction of thermal models of spacecraft. The work presented here has been conducted in cooperation with the company OHB AG, formerly Kayser-Threde GmbH, and the Institute of Astronautics at Technische Universität München with the goal to shorten and automatize the time-consuming and manual process of thermal model reduction. The reduction of thermal models can be divided into the simplification of the geometry model for calculation of external heat flows and radiative couplings and into the reduction of the underlying mathematical model. For simplification a method has been developed which approximates the reduced geometry model with the help of an optimization algorithm. Different linear and nonlinear model reduction techniques have been evaluated for their applicability in reduction of the mathematical model. Thereby the compatibility with the thermal analysis tool ESATAN-TMS is of major concern, which restricts the useful application of these methods. Additional model reduction methods have been developed, which account to these constraints. The Matrix Reduction method allows the approximation of the differential equation to reference values exactly expect for numerical errors. The summation method enables a useful, applicable reduction of thermal models that can be used in industry. In this work a framework for model reduction of thermal models has been created, which can be used together with a newly developed graphical user interface for the reduction of thermal models in industry.

  19. Lightweight, high-opacity paper : process costs and energy use reduction

    Treesearch

    John H. Klungness; Fabienne Pianta; Mathew L. Stroika; Marguerite Sykes; Freya Tan; Said AbuBakr

    1999-01-01

    Fiber loading is an environmentally friendly, energy efficient, and economical method for depositing precipitated calcium carbonate (PCC) partly within pulp fibers. Fiber loading can easily be done within the existing pulp processing system. This paper is a review of the process development from bench-scale to industrial-scale demonstrations, with additional...

  20. Fukunaga-Koontz transform based dimensionality reduction for hyperspectral imagery

    NASA Astrophysics Data System (ADS)

    Ochilov, S.; Alam, M. S.; Bal, A.

    2006-05-01

    Fukunaga-Koontz Transform based technique offers some attractive properties for desired class oriented dimensionality reduction in hyperspectral imagery. In FKT, feature selection is performed by transforming into a new space where feature classes have complimentary eigenvectors. Dimensionality reduction technique based on these complimentary eigenvector analysis can be described under two classes, desired class and background clutter, such that each basis function best represent one class while carrying the least amount of information from the second class. By selecting a few eigenvectors which are most relevant to desired class, one can reduce the dimension of hyperspectral cube. Since the FKT based technique reduces data size, it provides significant advantages for near real time detection applications in hyperspectral imagery. Furthermore, the eigenvector selection approach significantly reduces computation burden via the dimensionality reduction processes. The performance of the proposed dimensionality reduction algorithm has been tested using real-world hyperspectral dataset.

  1. MuLoG, or How to Apply Gaussian Denoisers to Multi-Channel SAR Speckle Reduction?

    PubMed

    Deledalle, Charles-Alban; Denis, Loic; Tabti, Sonia; Tupin, Florence

    2017-09-01

    Speckle reduction is a longstanding topic in synthetic aperture radar (SAR) imaging. Since most current and planned SAR imaging satellites operate in polarimetric, interferometric, or tomographic modes, SAR images are multi-channel and speckle reduction techniques must jointly process all channels to recover polarimetric and interferometric information. The distinctive nature of SAR signal (complex-valued, corrupted by multiplicative fluctuations) calls for the development of specialized methods for speckle reduction. Image denoising is a very active topic in image processing with a wide variety of approaches and many denoising algorithms available, almost always designed for additive Gaussian noise suppression. This paper proposes a general scheme, called MuLoG (MUlti-channel LOgarithm with Gaussian denoising), to include such Gaussian denoisers within a multi-channel SAR speckle reduction technique. A new family of speckle reduction algorithms can thus be obtained, benefiting from the ongoing progress in Gaussian denoising, and offering several speckle reduction results often displaying method-specific artifacts that can be dismissed by comparison between results.

  2. Nanoscale reduction of graphene oxide thin films and its characterization

    NASA Astrophysics Data System (ADS)

    Lorenzoni, M.; Giugni, A.; Di Fabrizio, E.; Pérez-Murano, Francesc; Mescola, A.; Torre, B.

    2015-07-01

    In this paper, we report on a method to reduce thin films of graphene oxide (GO) to a spatial resolution better than 100 nm over several tens of micrometers by means of an electrochemical scanning probe based lithography. In situ tip-current measurements show that an edged drop in electrical resistance characterizes the reduced areas, and that the reduction process is, to a good approximation, proportional to the applied bias between the onset voltage and the saturation thresholds. An atomic force microscope (AFM) quantifies the drop of the surface height for the reduced profile due to the loss of oxygen. Complementarily, lateral force microscopy reveals a homogeneous friction coefficient of the reduced regions that is remarkably lower than that of native graphene oxide, confirming a chemical change in the patterned region. Micro Raman spectroscopy, which provides access to insights into the chemical process, allows one to quantify the restoration and de-oxidation of the graphitic network driven by the electrochemical reduction and to determine characteristic length scales. It also confirms the homogeneity of the process over wide areas. The results shown were obtained from accurate analysis of the shift, intensity and width of Raman peaks for the main vibrational bands of GO and reduced graphene oxide (rGO) mapped over large areas. Concerning multilayered GO thin films obtained by drop-casting we have demonstrated an unprecedented lateral resolution in ambient conditions as well as an improved control, characterization and understanding of the reduction process occurring in GO randomly folded multilayers, useful for large-scale processing of graphene-based material.

  3. Voluntary GHG reduction of industrial sectors in Taiwan.

    PubMed

    Chen, Liang-Tung; Hu, Allen H

    2012-08-01

    The present paper describes the voluntary greenhouse gas (GHG) reduction agreements of six different industrial sectors in Taiwan, as well as the fluorinated gases (F-gas) reduction agreement of the semiconductor and Liquid Crystal Display (LCD) industries. The operating mechanisms, GHG reduction methods, capital investment, and investment effectiveness are also discussed. A total of 182 plants participated in the voluntary energy saving and GHG reduction in six industrial sectors (iron and steel, petrochemical, cement, paper, synthetic fiber, and textile printing and dyeing), with 5.35 Mt reduction from 2004 to 2008, or 33% higher than the target goal (4.02 Mt). The reduction accounts for 1.6% annual emission or 7.8% during the 5-yr span. The petrochemical industry accounts for 49% of the reduction, followed by the cement sector (21%) and the iron and steel industry (13%). The total investment amounted to approximately USD 716 million, in which, the majority of the investment went to the modification of the manufacturing process (89%). The benefit was valued at around USD 472 million with an average payback period of 1.5 yr. Moreover, related energy saving was achieved through different approaches, e.g., via electricity (iron and steel), steam and oil consumption (petrochemical) and coal usage (cement). The cost for unit CO(2) reduction varies per industry, with the steel and iron industrial sector having the highest cost (USD 346 t(-1) CO(2)) compared with the average cost of the six industrial sectors (USD 134 t(-1) CO(2)). For the semiconductor and Thin-Film Transistor LCD industries, F-gas emissions were reduced from approximately 4.1 to about 1.7 Mt CO(2)-eq, and from 2.2 to about 1.1 Mt CO(2)-eq, respectively. Incentive mechanisms for participation in GHG reduction are also further discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. The prospect of hazardous sludge reduction through gasification process

    NASA Astrophysics Data System (ADS)

    Hakiki, R.; Wikaningrum, T.; Kurniawan, T.

    2018-01-01

    Biological sludge generated from centralized industrial WWTP is classified as toxic and hazardous waste based on the Indonesian’s Government Regulation No. 101/2014. The amount of mass and volume of sludge produced have an impact in the cost to manage or to dispose. The main objective of this study is to identify the opportunity of gasification technology which can be applied to reduce hazardous sludge quantity before sending to the final disposal. This preliminary study covers the technical and economic assessment of the application of gasification process, which was a combination of lab-scale experimental results and assumptions based on prior research. The results showed that the process was quite effective in reducing the amount and volume of hazardous sludge which results in reducing the disposal costs without causing negative impact on the environment. The reduced mass are moisture and volatile carbon which are decomposed, while residues are fix carbon and other minerals which are not decomposed by thermal process. The economical simulation showed that the project will achieve payback period in 2.5 years, IRR value of 53 % and BC Ratio of 2.3. The further study in the pilot scale to obtain the more accurate design and calculations is recommended.

  5. Acoustical and Perceptual Comparison of Noise Reduction and Compression in Hearing Aids

    ERIC Educational Resources Information Center

    Brons, Inge; Houben, Rolph; Dreschler, Wouter A.

    2015-01-01

    Purpose: Noise reduction and dynamic-range compression are generally applied together in hearing aids but may have opposite effects on amplification. This study evaluated the acoustical and perceptual effects of separate and combined processing of noise reduction and compression. Design: Recordings of the output of 4 hearing aids for speech in…

  6. Automated Reduction and Calibration of SCUBA Archive Data Using ORAC-DR

    NASA Astrophysics Data System (ADS)

    Jenness, T.; Stevens, J. A.; Archibald, E. N.; Economou, F.; Jessop, N.; Robson, E. I.; Tilanus, R. P. J.; Holland, W. S.

    The Submillimetre Common User Bolometer Array (SCUBA) instrument has been operating on the James Clerk Maxwell Telescope (JCMT) since 1997. The data archive is now sufficiently large that it can be used for investigating instrumental properties and the variability of astronomical sources. This paper describes the automated calibration and reduction scheme used to process the archive data with particular emphasis on the pointing observations. This is made possible by using the ORAC-DR data reduction pipeline, a flexible and extensible data reduction pipeline that is used on UKIRT and the JCMT.

  7. 75 FR 28777 - Information Collection; Pre-Decisional Objection Process for Hazardous Fuel Reduction Projects...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-24

    ... the Healthy Forests Restoration Act of 2003 is the minimum necessary for an individual or organization... for Hazardous Fuel Reduction Projects Authorized by the Healthy Forest Restoration Act of 2003 AGENCY... organizations on the extension, with no revision, of a currently approved information collection, OMB 0596-0172...

  8. Performance of biofuel processes utilising separate lignin and carbohydrate processing.

    PubMed

    Melin, Kristian; Kohl, Thomas; Koskinen, Jukka; Hurme, Markku

    2015-09-01

    Novel biofuel pathways with increased product yields are evaluated against conventional lignocellulosic biofuel production processes: methanol or methane production via gasification and ethanol production via steam-explosion pre-treatment. The novel processes studied are ethanol production combined with methanol production by gasification, hydrocarbon fuel production with additional hydrogen produced from lignin residue gasification, methanol or methane synthesis using synthesis gas from lignin residue gasification and additional hydrogen obtained by aqueous phase reforming in synthesis gas production. The material and energy balances of the processes were calculated by Aspen flow sheet models and add on excel calculations applicable at the conceptual design stage to evaluate the pre-feasibility of the alternatives. The processes were compared using the following criteria: energy efficiency from biomass to products, primary energy efficiency, GHG reduction potential and economy (expressed as net present value: NPV). Several novel biorefinery concepts gave higher energy yields, GHG reduction potential and NPV. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. High performance of a cobalt–nitrogen complex for the reduction and reductive coupling of nitro compounds into amines and their derivatives

    PubMed Central

    Zhou, Peng; Jiang, Liang; Wang, Fan; Deng, Kejian; Lv, Kangle; Zhang, Zehui

    2017-01-01

    Replacement of precious noble metal catalysts with low-cost, non-noble heterogeneous catalysts for chemoselective reduction and reductive coupling of nitro compounds holds tremendous promise for the clean synthesis of nitrogen-containing chemicals. We report a robust cobalt–nitrogen/carbon (Co–Nx/C-800-AT) catalyst for the reduction and reductive coupling of nitro compounds into amines and their derivates. The Co–Nx/C-800-AT catalyst was prepared by the pyrolysis of cobalt phthalocyanine–silica colloid composites and the subsequent removal of silica template and cobalt nanoparticles. The Co–Nx/C-800-AT catalyst showed extremely high activity, chemoselectivity, and stability toward the reduction of nitro compounds with H2, affording full conversion and >97% selectivity in water after 1.5 hours at 110°C and under a H2 pressure of 3.5 bar for all cases. The hydrogenation of nitrobenzene over the Co–Nx/C-800-AT catalyst can even be smoothly performed under very mild conditions (40°C and a H2 pressure of 1 bar) with an aniline yield of 98.7%. Moreover, the Co–Nx/C-800-AT catalyst has high activity toward the transfer hydrogenation of nitrobenzene into aniline and the reductive coupling of nitrobenzene into other derivates with high yields. These processes were carried out in an environmentally friendly manner without base and ligands. PMID:28232954

  10. External Acoustic Liners for Multi-Functional Aircraft Noise Reduction

    NASA Technical Reports Server (NTRS)

    Jones, Michael G. (Inventor); Czech, Michael J. (Inventor); Howerton, Brian M. (Inventor); Thomas, Russell H. (Inventor); Nark, Douglas M. (Inventor)

    2017-01-01

    Acoustic liners for aircraft noise reduction include one or more chambers that are configured to provide a pressure-release surface such that the engine noise generation process is inhibited and/or absorb sound by converting the sound into heat energy. The size and shape of the chambers can be selected to inhibit the noise generation process and/or absorb sound at selected frequencies.

  11. High-Quality Reduced Graphene Oxide by a Dual-Function Chemical Reduction and Healing Process

    PubMed Central

    Some, Surajit; Kim, Youngmin; Yoon, Yeoheung; Yoo, HeeJoun; Lee, Saemi; Park, Younghun; Lee, Hyoyoung

    2013-01-01

    A new chemical dual-functional reducing agent, thiophene, was used to produce high-quality reduced graphene oxide (rGO) as a result of a chemical reduction of graphene oxide (GO) and the healing of rGO. Thiophene reduced GO by donation of electrons with acceptance of oxygen while it was converted into an intermediate oxidised polymerised thiophene that was eventually transformed into polyhydrocarbon by loss of sulphur atoms. Surprisingly, the polyhydrocarbon template helped to produce good-quality rGOC (chemically reduced) and high-quality rGOCT after thermal treatment. The resulting rGOCT nanosheets did not contain any nitrogen or sulphur impurities, were highly deoxygenated and showed a healing effect. Thus the electrical properties of the as-prepared rGOCT were superior to those of conventional hydrazine-produced rGO that require harsh reaction conditions. Our novel dual reduction and healing method with thiophene could potentially save energy and facilitate the commercial mass production of high-quality graphene. PMID:23722643

  12. [Ecological security of wastewater treatment processes: a review].

    PubMed

    Yang, Sai; Hua, Tao

    2013-05-01

    Though the regular indicators of wastewater after treatment can meet the discharge requirements and reuse standards, it doesn't mean the effluent is harmless. From the sustainable point of view, to ensure the ecological and human security, comprehensive toxicity should be considered when discharge standards are set up. In order to improve the ecological security of wastewater treatment processes, toxicity reduction should be considered when selecting and optimizing the treatment processes. This paper reviewed the researches on the ecological security of wastewater treatment processes, with the focus on the purposes of various treatment processes, including the processes for special wastewater treatment, wastewater reuse, and for the safety of receiving waters. Conventional biological treatment combined with advanced oxidation technologies can enhance the toxicity reduction on the base of pollutants removal, which is worthy of further study. For the process aimed at wastewater reuse, the integration of different process units can complement the advantages of both conventional pollutants removal and toxicity reduction. For the process aimed at ecological security of receiving waters, the emphasis should be put on the toxicity reduction optimization of process parameters and process unit selection. Some suggestions for the problems in the current research and future research directions were put forward.

  13. Production of Magnesium by Vacuum Aluminothermic Reduction with Magnesium Aluminate Spinel as a By-Product

    NASA Astrophysics Data System (ADS)

    Wang, Yaowu; You, Jing; Peng, Jianping; Di, Yuezhong

    2016-06-01

    The Pidgeon process currently accounts for 85% of the world's magnesium production. Although the Pidgeon process has been greatly improved over the past 10 years, such production still consumes much energy and material and creates much pollution. The present study investigates the process of producing magnesium by employing vacuum aluminothermic reduction and by using magnesite as material and obtaining magnesium aluminate spinel as a by-product. The results show that compared with the Pidgeon process, producing magnesium by vacuum aluminothermic reduction can save materials by as much as 50%, increase productivity up to 100%, and save energy by more than 50%. It can also reduce CO2 emission by up to 60% and realize zero discharge of waste residue. Vacuum aluminothermic reduction is a highly efficient, low-energy-consumption, and environmentally friendly method of producing magnesium.

  14. Metal and alloy nanoparticles by amine-borane reduction of metal salts by solid-phase synthesis: atom economy and green process.

    PubMed

    Sanyal, Udishnu; Jagirdar, Balaji R

    2012-12-03

    A new solid state synthetic route has been developed toward metal and bimetallic alloy nanoparticles from metal salts employing amine-boranes as the reducing agent. During the reduction, amine-borane plays a dual role: acts as a reducing agent and reduces the metal salts to their elemental form and simultaneously generates a stabilizing agent in situ which controls the growth of the particles and stabilizes them in the nanosize regime. Employing different amine-boranes with differing reducing ability (ammonia borane (AB), dimethylamine borane (DMAB), and triethylamine borane (TMAB)) was found to have a profound effect on the particle size and the size distribution. Usage of AB as the reducing agent provided the smallest possible size with best size distribution. Employment of TMAB also afforded similar results; however, when DMAB was used as the reducing agent it resulted in larger sized nanoparticles that are polydisperse too. In the AB mediated reduction, BNH(x) polymer generated in situ acts as a capping agent whereas, the complexing amine of the other amine-boranes (DMAB and TMAB) play the same role. Employing the solid state route described herein, monometallic Au, Ag, Cu, Pd, and Ir and bimetallic CuAg and CuAu alloy nanoparticles of <10 nm were successfully prepared. Nucleation and growth processes that control the size and the size distribution of the resulting nanoparticles have been elucidated in these systems.

  15. Efficient reductive amination process for enantioselective synthesis of L-phosphinothricin applying engineered glutamate dehydrogenase.

    PubMed

    Yin, Xinjian; Wu, Jianping; Yang, Lirong

    2018-05-01

    The objective of this study was to identify and exploit a robust biocatalyst that can be applied in reductive amination for enantioselective synthesis of the competitive herbicide L-phosphinothricin. Applying a genome mining-based library construction strategy, eight NADPH-specific glutamate dehydrogenases (GluDHs) were identified for reductively aminating 2-oxo-4-[(hydroxy)(methyl)phosphinoyl]butyric acid (PPO) to L-phosphinothricin. Among them, the glutamate dehydrogenase cloned from Pseudomonas putida (PpGluDH) exhibited relatively high catalytic activity and favorable soluble expression. This enzyme was purified to homogeneity for further characterization. The specific activity of PpGluDH was 296.1 U/g-protein, which is significantly higher than the reported value for a GluDH. To the best of our knowledge, there has not been any report on protein engineering of GluDH for PPO-oriented activity. Taking full advantage of the available information and the diverse characteristics of the enzymes in the enzyme library, PpGluDH was engineered by site-directed mutation based on multiple sequence alignment. The mutant I170M, which had 2.1-fold enhanced activity, was successfully produced. When the I170M mutant was applied in the batch production of L-phosphinothricin, it showed markedly improved catalytic efficiency compared with the wild type enzyme. The conversion reached 99% (0.1 M PPO) with an L-phosphinothricin productivity of 1.35 g/h·L, which far surpassed the previously reported level. These results show that PpGluDH I170M is a promising biocatalyst for highly enantioselective synthesis of L-phosphinothricin by reductive amination.

  16. Mechanism of sodium chloride in promoting reduction of high-magnesium low-nickel oxide ore

    PubMed Central

    Zhou, Shiwei; Wei, Yonggang; Li, Bo; Wang, Hua; Ma, Baozhong; Wang, Chengyan

    2016-01-01

    Sodium chloride has been proved that it is an effective promoter for the reduction of high-magnesium, low-nickel oxide ore. The aim of current work is to clarify the promotion behavior of sodium chloride in the roasting reduction process. The influence of moisture on the reduction of ore in the presence of sodium chloride is studied to get clear comprehension of promotion process. In the presence of moisture, the HCl is produced by pyrohydrolysis of sodium chloride for chlorinating nickel and iron oxides, moreover, interactions between metallic oxides and sodium chloride are also a way for chlorination at high temperature (>802 °C); subsequently, the metal chloride would be reduced by reductant. In the absence of moisture, the magnetic separation results show that the recoveries of iron and nickel have a significant increase; moreover, olivine structure would be destroyed gradually with the increase of roasting temperature in the action of sodium chloride, and the sodium chloride existed in high-magnesium, low-nickel oxide ore could make the NiO isolate from NiO-bearing minerals. The NiO reacts with Fe2O3 at high temperature to form NiFe2O4, which is conductive to the formation of Ni-Fe alloy during the reduction process. PMID:27374991

  17. Mechanism of sodium chloride in promoting reduction of high-magnesium low-nickel oxide ore.

    PubMed

    Zhou, Shiwei; Wei, Yonggang; Li, Bo; Wang, Hua; Ma, Baozhong; Wang, Chengyan

    2016-07-04

    Sodium chloride has been proved that it is an effective promoter for the reduction of high-magnesium, low-nickel oxide ore. The aim of current work is to clarify the promotion behavior of sodium chloride in the roasting reduction process. The influence of moisture on the reduction of ore in the presence of sodium chloride is studied to get clear comprehension of promotion process. In the presence of moisture, the HCl is produced by pyrohydrolysis of sodium chloride for chlorinating nickel and iron oxides, moreover, interactions between metallic oxides and sodium chloride are also a way for chlorination at high temperature (>802 °C); subsequently, the metal chloride would be reduced by reductant. In the absence of moisture, the magnetic separation results show that the recoveries of iron and nickel have a significant increase; moreover, olivine structure would be destroyed gradually with the increase of roasting temperature in the action of sodium chloride, and the sodium chloride existed in high-magnesium, low-nickel oxide ore could make the NiO isolate from NiO-bearing minerals. The NiO reacts with Fe2O3 at high temperature to form NiFe2O4, which is conductive to the formation of Ni-Fe alloy during the reduction process.

  18. Microfluidic platform for studying the electrochemical reduction of carbon dioxide

    NASA Astrophysics Data System (ADS)

    Whipple, Devin Talmage

    Diminishing supplies of conventional energy sources and growing concern over greenhouse gas emissions present significant challenges to supplying the world's rapidly increasing demand for energy. The electrochemical reduction of carbon dioxide has the potential to address many of these issues by providing a means of storing electricity in chemical form. Storing electrical energy as chemicals is beneficial for leveling the output of clean, but intermittent renewable energy sources such as wind and solar. Electrical energy stored as chemicals can also be used as carbon neutral fuels for portable applications allowing petroleum derived fuels in the transportation sector to be replaced by more environmentally friendly energy sources. However, to be a viable technology, the electrochemical reduction of carbon dioxide needs to have both high current densities and energetic efficiencies (Chapter 1). Although many researchers have studied the electrochemical reduction of CO2 including parameters such as catalysts, electrolytes and temperature, further investigation is needed to improve the understanding of this process and optimize the performance (Chapter 2). This dissertation reports the development and validation of a microfluidic reactor for the electrochemical reduction of CO2 (Chapter 3). The design uses a flowing liquid electrolyte instead of the typical polymer electrolyte membrane. In addition to other benefits, this flowing electrolyte gives the reactor great flexibility, allowing independent analysis of each electrode and the testing of a wide variety of conditions. In this work, the microfluidic reactor has been used in the following areas: • Comparison of different metal catalysts for the reduction of CO2 to formic acid and carbon monoxide (Chapter 4). • Investigation of the effects of the electrolyte pH on the reduction of CO2 to formic acid and carbon monoxide (Chapter 5). • Study of amine based electrolytes for lowering the overpotentials for CO2

  19. Color reduction of sulfonated eucalyptus kraft lignin.

    PubMed

    Zhang, Hui; Bai, Youcan; Zhou, Wanpeng; Chen, Fangeng

    2017-04-01

    Several eucalyptus lignins named as HSL, SML and BSL were prepared by high temperature sulfonation, sulfomethylation, butane sultone sulfonation respectively. The color properties of samples were investigated. Under optimized conditions the sulfonic group (SO 3 H) content of HSL, SML and BSL reached 1.52, 1.60 and 1.58mmol/g, respectively. Samples were characterized by UV-vis spectroscopy, FTIR spectroscopy, 1 H NMR spectroscopy, GPC and brightness test, respectively. The results revealed that BSL performed a higher molecular weight and lighter color due to the phenolic hydroxyl blocking by 1,4-butane sultone (1,4-BS). The color reduction of sodium borohydride treated BSL (labeled as SBSL) was further enhanced and the brightness value was improved by 76.1% compared with the darkest HSL. SBSL process was much better than HSL and SML process. Hydroxyl blocking effect of 1,4-BS and reducibility of sodium borohydride played important roles in the color reduction of sulfonated eucalyptus kraft lignin. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Reductive dehalogenase structure suggests a mechanism for B12-dependent dehalogenation

    PubMed Central

    Fisher, Karl; Dunstan, Mark S; Collins, Fraser A; Sjuts, Hanno; Levy, Colin; Hay, Sam; Rigby, Stephen EJ; Leys, David

    2015-01-01

    Organohalide chemistry underpins many industrial and agricultural processes, and a large proportion of environmental pollutants are organohalides1. Nevertheless, organohalide chemistry is not exclusively of anthropogenic origin, with natural abiotic and biological processes contributing to the global halide cycle2–3. Reductive dehalogenases are responsible for biological dehalogenation in organohalide respiring bacteria4–5, with substrates including the notorious polychlorinated biphenyls (PCBs) or dioxins6–7. These proteins form a distinct subfamily of cobalamin (B12) dependent enzymes that are usually membrane-associated and oxygen-sensitive, hindering detailed studies8–12. We report the characterisation of a soluble, oxygen-tolerant reductive dehalogenase and, by combining structure determination with EPR spectroscopy and simulation, show that a direct interaction between the cobalamin cobalt and the substrate halogen underpins catalysis. In contrast to the carbon-Co bond chemistry catalyzed by the other cobalamin-dependent subfamilies13 we propose that reductive dehalogenases achieve reduction of the organohalide substrate via halogen-Co bond formation. This presents a new paradigm in both organohalide and cobalamin (bio)chemistry that will guide future exploitation of these enzymes in bioremediation or biocatalysis. PMID:25327251

  1. Massive-training support vector regression and Gaussian process for false-positive reduction in computer-aided detection of polyps in CT colonography

    PubMed Central

    Xu, Jian-Wu; Suzuki, Kenji

    2011-01-01

    Purpose: A massive-training artificial neural network (MTANN) has been developed for the reduction of false positives (FPs) in computer-aided detection (CADe) of polyps in CT colonography (CTC). A major limitation of the MTANN is the long training time. To address this issue, the authors investigated the feasibility of two state-of-the-art regression models, namely, support vector regression (SVR) and Gaussian process regression (GPR) models, in the massive-training framework and developed massive-training SVR (MTSVR) and massive-training GPR (MTGPR) for the reduction of FPs in CADe of polyps. Methods: The authors applied SVR and GPR as volume-processing techniques in the distinction of polyps from FP detections in a CTC CADe scheme. Unlike artificial neural networks (ANNs), both SVR and GPR are memory-based methods that store a part of or the entire training data for testing. Therefore, their training is generally fast and they are able to improve the efficiency of the massive-training methodology. Rooted in a maximum margin property, SVR offers excellent generalization ability and robustness to outliers. On the other hand, GPR approaches nonlinear regression from a Bayesian perspective, which produces both the optimal estimated function and the covariance associated with the estimation. Therefore, both SVR and GPR, as the state-of-the-art nonlinear regression models, are able to offer a performance comparable or potentially superior to that of ANN, with highly efficient training. Both MTSVR and MTGPR were trained directly with voxel values from CTC images. A 3D scoring method based on a 3D Gaussian weighting function was applied to the outputs of MTSVR and MTGPR for distinction between polyps and nonpolyps. To test the performance of the proposed models, the authors compared them to the original MTANN in the distinction between actual polyps and various types of FPs in terms of training time reduction and FP reduction performance. The authors’ CTC database

  2. Sugar reduction without compromising sensory perception. An impossible dream?

    PubMed

    Hutchings, Scott C; Low, Julia Y Q; Keast, Russell S J

    2018-03-21

    Sugar reduction is a major technical challenge for the food industry to address in response to public health concerns regarding the amount of added sugars in foods. This paper reviews sweet taste perception, sensory methods to evaluate sugar reduction and the merits of different techniques available to reduce sugar content. The use of sugar substitutes (non-nutritive sweeteners, sugar alcohols, and fibres) can achieve the greatest magnitude of sugar and energy reduction, however bitter side tastes and varying temporal sweet profiles are common issues. The use of multisensory integration principles (particularly aroma) can be an effective approach to reduce sugar content, however the magnitude of sugar reduction is small. Innovation in food structure (modifying the sucrose distribution, serum release and fracture mechanics) offers a new way to reduce sugar without significant changes in food composition, however may be difficult to implement in food produced on a large scale. Gradual sugar reduction presents difficulties for food companies from a sales perspective if acceptability is compromised. Ultimately, a holistic approach where food manufacturers integrate a range of these techniques is likely to provide the best progress. However, substantial reduction of sugar in processed foods without compromising sensory properties may be an impossible dream.

  3. Direct chemical reduction of neptunium oxide to neptunium metal using calcium and calcium chloride

    DOE PAGES

    Squires, Leah N.; Lessing, Paul

    2016-01-13

    A process of direct reduction of neptunium oxide to neptunium metal using calcium metal as the reducing agent is discussed. After reduction of the oxide to metal, the metal is separated by density from the other components of the reaction mixture and can easily removed upon cooling. Furthermore, the direct reduction technique consistently produces high purity (98%–99% pure) neptunium metal.

  4. Reduction of uranium hexafluoride to tetrafluoride by using the hydrogen atoms

    NASA Astrophysics Data System (ADS)

    Aleksandrov, B. P.; Gordon, E. B.; Ivanov, A. V.; Kotov, A. A.; Smirnov, V. E.

    2016-09-01

    We consider the reduction of UF6 to UF4 by chemical reaction with hydrogen atoms originated in the powerful chemical generator. The principal design of such a chemical convertor is described. The results of the mathematical modeling of the thermodynamics and kinetics of the UF6 to UF4 reduction process are analyzed. The few options for the hydrogen atom generator design are proposed. A layout of the experimental setup with the chemical reactor is presented. The high efficiency together with the ability of the process scaling without loss of its efficiency makes this approach to the uranium hexafluoride depletion into tetrafluoride promising for its application in the industry.

  5. Patterning and reduction of graphene oxide using femtosecond-laser irradiation

    NASA Astrophysics Data System (ADS)

    Kang, SeungYeon; Evans, Christopher C.; Shukla, Shobha; Reshef, Orad; Mazur, Eric

    2018-07-01

    Graphene has emerged as one of the most versatile materials ever discovered due to its extraordinary electronic, optical, thermal, and mechanical properties. However, device fabrication is a well-known challenge and requires novel fabrication methods to realize the complex integration of graphene-based devices. Here, we demonstrate direct laser writing of reduced graphene oxide using femtosecond-laser irradiation at λ = 795 nm. We perform a systematic study of the reduction process of graphene oxide to graphene by varying both the laser fluence and the pulse repetition rate. Our observations show that the reduction has both thermal and non-thermal features, and suggest that we can achieve better resolution and conductivity using kHz pulse trains than using MHz pulse trains or a continuous wave laser. Our reduced graphene oxide lines written at 10-kHz exhibit a 5 order-of-magnitude decrease in resistivity compared to a non-irradiated control sample. This study provides new insight into the reduction process of graphene oxide and opens doors to achieving a high degree of flexibility and control in the fabrication of graphene layers.

  6. Constructing a holistic approach to disaster risk reduction: the significance of focusing on vulnerability reduction.

    PubMed

    Palliyaguru, Roshani; Amaratunga, Dilanthi; Baldry, David

    2014-01-01

    As a result of the increase in natural disaster losses, policy-makers, practitioners, and members of the research community around the world are seeking effective and efficient means of overcoming or minimising them. Although various theoretical constructs are beneficial to understanding the disaster phenomenon and the means of minimising losses, the disaster risk management process becomes less effective if theory and practice are set apart from one another. Consequently, this paper seeks to establish a relationship between two theoretical constructs, 'disaster risk reduction (DRR)' and 'vulnerability reduction', and to develop a holistic approach to DRR with particular reference to improving its applicability in practical settings. It is based on a literature review and on an overall understanding gained through two case studies of post-disaster infrastructure reconstruction projects in Sri Lanka and three expert interviews in Sri Lanka and the United Kingdom. © 2014 The Author(s). Disasters © Overseas Development Institute, 2014.

  7. Preparation of Ferrotitanium from Ilmenite by Electrolysis-Assisted Calciothermic Reduction in CaCl2-NaCl Molten Salt

    NASA Astrophysics Data System (ADS)

    Zhou, Zhongren; Hua, Yixin; Xu, Cunying; Li, Jian; Li, Yan; Gong, Kai; Ru, Juanjian; Xiong, Li

    2016-02-01

    Electrolysis-assisted calciothermic reduction method is proposed and successfully used to prepare ferrotitanium alloy from ilmenite by using equal-molar CaCl2-NaCl molten salt as electrolyte, molybdenum rod as cathode, and graphite as anode at 973 K with cell voltages of 3.2-4.4 V under inert atmosphere. Thermodynamics analysis of the process is presented, and the products obtained are examined with x-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy. It is demonstrated that the calciothermic reduction of ilmenite is a stepwise process since intermediate CaTiO3 is observed in the products partially reduced. In the calciothermic reduction process, the reduction of FeTiO3 first gives rise to the formation of Fe and CaTiO3, which as intermediates will further react with calcium metal to form ferrotitanium alloys. This is in good agreement with the prediction of thermodynamics. Experimental results also show that increasing cell voltage can accelerate the formation of calcium metal through electrolysis of CaO and CaCl2 and, hence, promote the calciothermic reduction of ilmenite. As the electrolytic zone and reduction zone are combined in the same bath, the theoretical energy requirement for the production of FeTi in the calciothermic process is lower than that in the aluminothermic process.

  8. Failure detection system risk reduction assessment

    NASA Technical Reports Server (NTRS)

    Aguilar, Robert B. (Inventor); Huang, Zhaofeng (Inventor)

    2012-01-01

    A process includes determining a probability of a failure mode of a system being analyzed reaching a failure limit as a function of time to failure limit, determining a probability of a mitigation of the failure mode as a function of a time to failure limit, and quantifying a risk reduction based on the probability of the failure mode reaching the failure limit and the probability of the mitigation.

  9. Cognitive dissonance reduction as constraint satisfaction.

    PubMed

    Shultz, T R; Lepper, M R

    1996-04-01

    A constraint satisfaction neural network model (the consonance model) simulated data from the two major cognitive dissonance paradigms of insufficient justification and free choice. In several cases, the model fit the human data better than did cognitive dissonance theory. Superior fits were due to the inclusion of constraints that were not part of dissonance theory and to the increased precision inherent to this computational approach. Predictions generated by the model for a free choice between undesirable alternatives were confirmed in a new psychological experiment. The success of the consonance model underscores important, unforeseen similarities between what had been formerly regarded as the rather exotic process of dissonance reduction and a variety of other, more mundane psychological processes. Many of these processes can be understood as the progressive application of constraints supplied by beliefs and attitudes.

  10. Enhanced Nitrobenzene reduction by zero valent iron pretreated with H2O2/HCl.

    PubMed

    Yang, Zhe; Ma, Xiaowen; Shan, Chao; Fang, Zhuoyao; Pan, Bingcai

    2018-04-01

    In this study a novel iron-based reducing agent of highly effective reduction toward nitrobenzene (NB) was obtained by pretreating zero valent iron (ZVI) with H 2 O 2 /HCl. During the H 2 O 2 /HCl pretreatment, ZVI undergoes an intensive corrosion process with formation of various reducing corrosion products (e.g., Fe 2+ , ferrous oxides/hydroxides, Fe 3 O 4 ), yielding a synergetic system (prtZVI) including liquid, suspensions and solid phase. The pretreatment process remarkably enhances the reductive performance of ZVI, where a rapid reduction of NB (200 mg L -1 ) in the prtZVI suspension was accomplished in a broad pH range (3-9) and at low dosage. Nitrosobenzene and phenylhydroxylamine are identified as the intermediates for NB reduction with the end-product of aniline. Compared with the virgin ZVI as well as another nanosized ZVI, the prtZVI system exhibits much higher electron efficiency for NB reduction as well as higher utilization ratio of Fe 0 . A rapid reduction of various nitroaromatics in an actual pharmaceutical wastewater further demonstrated the feasibility of the prtZVI system in real wastewater treatment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Numerical analysis of ammonia homogenization for selective catalytic reduction application.

    PubMed

    Baleta, Jakov; Martinjak, Matija; Vujanović, Milan; Pachler, Klaus; Wang, Jin; Duić, Neven

    2017-12-01

    Selective catalytic reduction based on urea water solution as ammonia precursor is a promising method for the NO x abatement form exhaust gasses of mobile diesel engine units. It consists of injecting the urea-water solution in the hot flue gas stream and reaction of its products with the NO x over the catalyst surface. During this process flue gas enthalpy is used for the urea-water droplet heating and for the evaporation of water content. After water evaporates, thermolysis of urea occurs, during which ammonia, a known NO x reductant, and isocyanic acid are generated. The uniformity of the ammonia before the catalyst as well as ammonia slip to the environment are important counteracting design requirements, optimization of which is crucial for development of efficient deNO x systems. The aim of this paper is to show capabilities of the developed mathematical framework implemented in the commercial CFD code AVL FIRE ® , to simulate physical processes of all relevant phenomena occurring during the SCR process including chemical reactions taking part in the catalyst. First, mathematical models for description of SCR process are presented and afterwards, models are used on the 3D geometry of a real SCR reactor in order to predict ammonia generation, NO x reduction and resulting ammonia slip. Influence of the injection direction and droplet sizes was also investigated on the same geometry. The performed study indicates importance of droplet sizes on the SCR process and shows that counterflow injection is beneficial, especially in terms of minimizing harmful ammonia slip to environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Possible rainfall reduction through reduced surface temperatures due to overgrazing

    NASA Technical Reports Server (NTRS)

    Otterman, J.

    1975-01-01

    Surface temperature reduction in terrain denuded of vegetation (as by overgrazing) is postulated to decrease air convection, reducing cloudiness and rainfall probability during weak meteorological disturbances. By reducing land-sea daytime temperature differences, the surface temperature reduction decreases daytime circulation of thermally driven local winds. The described desertification mechanism, even when limited to arid regions, high albedo soils, and weak meteorological disturbances, can be an effective rainfall reducing process in many areas including most of the Mediterranean lands.

  13. Enema reduction of intussusception: the success rate of hydrostatic and pneumatic reduction.

    PubMed

    Khorana, Jiraporn; Singhavejsakul, Jesda; Ukarapol, Nuthapong; Laohapensang, Mongkol; Wakhanrittee, Junsujee; Patumanond, Jayanton

    2015-01-01

    Intussusception is a common surgical emergency in infants and children. The incidence of intussusception is from one to four per 2,000 infants and children. If there is no peritonitis, perforation sign on abdominal radiographic studies, and nonresponsive shock, nonoperative reduction by pneumatic or hydrostatic enema can be performed. The purpose of this study was to compare the success rates of both the methods. Two institutional retrospective cohort studies were performed. All intussusception patients (ICD-10 code K56.1) who had visited Chiang Mai University Hospital and Siriraj Hospital from January 2006 to December 2012 were included in the study. The data were obtained by chart reviews and electronic databases, which included demographic data, symptoms, signs, and investigations. The patients were grouped according to the method of reduction followed into pneumatic reduction and hydrostatic reduction groups with the outcome being the success of the reduction technique. One hundred and seventy episodes of intussusception occurring in the patients of Chiang Mai University Hospital and Siriraj Hospital were included in this study. The success rate of pneumatic reduction was 61% and that of hydrostatic reduction was 44% (P=0.036). Multivariable analysis and adjusting of the factors by propensity scores were performed; the success rate of pneumatic reduction was 1.48 times more than that of hydrostatic reduction (P=0.036, 95% confidence interval [CI] =1.03-2.13). Both pneumatic and hydrostatic reduction can be performed safely according to the experience of the radiologist or pediatric surgeon and hospital setting. This study showed that pneumatic reduction had a higher success rate than hydrostatic reduction.

  14. Electrochemical reduction of (U-40Pu-5Np)O 2 in molten LiCl electrolyte

    NASA Astrophysics Data System (ADS)

    Iizuka, Masatoshi; Sakamura, Yoshiharu; Inoue, Tadashi

    2006-12-01

    The electrochemical reduction of neptunium-containing MOX ((U-40Pu-5Np)O 2) was performed in molten lithium chloride melt at 923 K to investigate fundamental behavior of the transuranium elements and applicability of the method to reduction process for these materials. The Np-MOX was electrochemically reduced at the potential lower than -0.6 V vs. Bi-35 mol% Li reference electrode. The reduced metal grains in the surface region of the sample cohered with each other and made the layer of relatively high density, although it did not prevent the reduction of the sample toward the center. Complete reduction of the Np-MOX was shown by the weight change measurement through the electrochemical reduction and also by SEM-EDX observation. The chemical composition of the reduction products was homogeneous and agreed to that of the initial Np-MOX, which indicates that the reduction was completed and not selective among the actinides. The concentrations of the actinide elements, especially plutonium and americium in the electrolyte, increased with the progress of the tests, although their absolute values were very small. It is quite likely that plutonium and americium dissolve into the melt in the same manner as the lanthanide elements in the lithium reduction process.

  15. INHIBITION OF REDUCTIVE DECHLORINATION BY SULFATE REDUCTION IN MICROCOSMS (ABSTRACT ONLY)

    EPA Science Inventory

    High sulfate (>1,000 mg/L) concentrations are potentially problematic for field implementation of in situ bioremediation of chlorinated ethenes because its reduction competes for electron donor with reductive dechlorination. As a result of this competition, reductive dechl...

  16. On the evolution of morphology of zirconium sponge during reduction and distillation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kapoor, K.; Padmaprabu, C.; Nandi, D.

    2008-03-15

    High purity zirconium metal is produced by magnesio-thermic reduction of zirconium tetrachloride followed by vacuum distillation. The reduction process is carried out in a batch giving metal sponge and magnesium chloride in the reduced mass. The sponge is purified to using by vacuum distillation. The morphology of the sponge formed during the reduction and its influence on further processing has significant importance. In the present study, a detailed investigation involving evolution of the morphology of sponge particles and its implication during the vacuum distillation was carried out. The study of the microstructure was done using scanning electron microscopy and X-raymore » diffraction. It is observed that the nascent sponge formed is highly unstable which transforms to a needle-like morphology almost immediately, which further transforms to rounded and finally to a bulk shape. Faceting of the surface and needle-shape formation were observed in these particles, this is probably due to anisotropy in the surface energy. The morphology of the sponge formed during the reduction influences the distillation process. The fine needle-like shape sponge morphology leads to particle ejection, which is explained to be due to curvature effect. This is responsible for the formation of unwanted mass during distillation. XRD line broadening analysis indicates that the individual sponge particles are free from structural defects (dislocation) and are nearly single crystalline in nature.« less

  17. Advances in Photocatalytic CO₂ Reduction with Water: A Review.

    PubMed

    Nahar, Samsun; Zain, M F M; Kadhum, Abdul Amir H; Hasan, Hassimi Abu; Hasan, Md Riad

    2017-06-08

    In recent years, the increasing level of CO₂ in the atmosphere has not only contributed to global warming but has also triggered considerable interest in photocatalytic reduction of CO₂. The reduction of CO₂ with H₂O using sunlight is an innovative way to solve the current growing environmental challenges. This paper reviews the basic principles of photocatalysis and photocatalytic CO₂ reduction, discusses the measures of the photocatalytic efficiency and summarizes current advances in the exploration of this technology using different types of semiconductor photocatalysts, such as TiO₂ and modified TiO₂, layered-perovskite Ag/ALa₄Ti₄O 15 (A = Ca, Ba, Sr), ferroelectric LiNbO₃, and plasmonic photocatalysts. Visible light harvesting, novel plasmonic photocatalysts offer potential solutions for some of the main drawbacks in this reduction process. Effective plasmonic photocatalysts that have shown reduction activities towards CO₂ with H₂O are highlighted here. Although this technology is still at an embryonic stage, further studies with standard theoretical and comprehensive format are suggested to develop photocatalysts with high production rates and selectivity. Based on the collected results, the immense prospects and opportunities that exist in this technique are also reviewed here.

  18. Differential effect of biochar upon reduction-induced mobility and bioavailability of arsenate and chromate.

    PubMed

    Choppala, Girish; Bolan, Nanthi; Kunhikrishnan, Anitha; Bush, Richard

    2016-02-01

    Heavy metals such as chromium (Cr) and arsenic (As) occur in ionic form in soil, with chromate [Cr(VI)] and arsenate As(V) being the most pre-dominant forms. The application of biochar to Cr(VI) and As(V) spiked and field contaminated soils was evaluated on the reduction processes [(Cr(VI) to Cr(III)] and [As(V) to As(III))], and subsequent mobility and bioavailability of both As(V) and Cr(VI). The assays used in this study included leaching, soil microbial activity and XPS techniques. The reduction rate of As(V) was lower than that of Cr(VI) with and without biochar addition, however, supplementation with biochar enhanced the reduction process of As(V). Leaching experiments indicated Cr(VI) was more mobile than As(V). Addition of biochar reversed the effect by reducing the mobility of Cr and increasing that of As. The presence of Cr and As in both spiked and contaminated soils reduced microbial activity, but with the addition of biochar to these soils, the microbial activity increased in the Cr(VI) contaminated soils, while it was further decreased with As(V) contaminated soils. The addition of biochar was effective in mitigating Cr toxicity by reducing Cr(VI) to Cr(III). In contrast, the conversion process of As(V) to As(III) hastened by biochar was not favourable, as As(III) is more toxic in soils. Overall, the presence of functional groups on biochar promotes reduction by providing the electrons required for reduction processes to occur as determined by XPS data. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. What Goes Around: the process of building a community-based harm reduction research project.

    PubMed

    Jalloh, Chelsea; Illsley, Shohan; Wylie, John; Migliardi, Paula; West, Ethan; Stewart, Debbie; Mignone, Javier

    2017-11-16

    Often, research takes place on underserved populations rather than with underserved populations. This approach can further isolate and stigmatize groups that are already made marginalized. What Goes Around is a community-based research project that was led by community members themselves (Peers). This research aimed to implement a community-based research methodology grounded in the leadership and growing research capacity of community researchers and to investigate a topic which community members identified as important and meaningful. Chosen by community members, this project explored how safer sex and safer drug use information is shared informally among Peers. Seventeen community members actively engaged as both community researchers and research participants throughout all facets of the project: inception, implementation, analysis, and dissemination of results. Effective collaboration between community researchers, a community organization, and academics facilitated a research process in which community members actively guided the project from beginning to end. The methods used in What Goes Around demonstrated that it is not only possible, but advantageous, to draw from community members' involvement and direction in all stages of a community-based research project. This is particularly important when working with a historically underserved population. Purposeful and regular communication among collaborators, ongoing capacity building, and a commitment to respect the experience and expertise of community members were essential to the project's success. This project demonstrated that community members are highly invested in both informally sharing information about safer sex and safer drug use and taking leadership roles in directing research that prioritizes harm reduction in their communities.

  20. Reductive Dehalogenation of Organic Contaminants in Soils and Ground Water

    EPA Pesticide Factsheets

    Reductive dehalogenation is a process which may prove to be of paramount importance in dealing with a particularly persistent class of contaminants often found in soil and ground water at superfund sites.

  1. The Development of Models for Carbon Dioxide Reduction Technologies for Spacecraft Air Revitalization

    NASA Technical Reports Server (NTRS)

    Swickrath, Michael J.; Anderson, Molly

    2012-01-01

    Through the respiration process, humans consume oxygen (O2) while producing carbon dioxide (CO2) and water (H2O) as byproducts. For long term space exploration, CO2 concentration in the atmosphere must be managed to prevent hypercapnia. Moreover, CO2 can be used as a source of oxygen through chemical reduction serving to minimize the amount of oxygen required at launch. Reduction can be achieved through a number of techniques. NASA is currently exploring the Sabatier reaction, the Bosch reaction, and co- electrolysis of CO2 and H2O for this process. Proof-of-concept experiments and prototype units for all three processes have proven capable of returning useful commodities for space exploration. All three techniques have demonstrated the capacity to reduce CO2 in the laboratory, yet there is interest in understanding how all three techniques would perform at a system level within a spacecraft. Consequently, there is an impetus to develop predictive models for these processes that can be readily rescaled and integrated into larger system models. Such analysis tools provide the ability to evaluate each technique on a comparable basis with respect to processing rates. This manuscript describes the current models for the carbon dioxide reduction processes under parallel developmental efforts. Comparison to experimental data is provided were available for verification purposes.

  2. The Development of Models for Carbon Dioxide Reduction Technologies for Spacecraft Air Revitalization

    NASA Technical Reports Server (NTRS)

    Swickrath, Michael J.; Anderson, Molly

    2011-01-01

    Through the respiration process, humans consume oxygen (O2) while producing carbon dioxide (CO2) and water (H2O) as byproducts. For long term space exploration, CO2 concentration in the atmosphere must be managed to prevent hypercapnia. Moreover, CO2 can be used as a source of oxygen through chemical reduction serving to minimize the amount of oxygen required at launch. Reduction can be achieved through a number of techniques. The National Aeronautics and Space Administration (NASA) is currently exploring the Sabatier reaction, the Bosch reaction, and co-electrolysis of CO2 and H2O for this process. Proof-of-concept experiments and prototype units for all three processes have proven capable of returning useful commodities for space exploration. While all three techniques have demonstrated the capacity to reduce CO2 in the laboratory, there is interest in understanding how all three techniques would perform at a system-level within a spacecraft. Consequently, there is an impetus to develop predictive models for these processes that can be readily re-scaled and integrated into larger system models. Such analysis tools provide the ability to evaluate each technique on a comparable basis with respect to processing rates. This manuscript describes the current models for the carbon dioxide reduction processes under parallel developmental e orts. Comparison to experimental data is provided were available for veri cation purposes.

  3. Waste reduction plan for The Oak Ridge National Laboratory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schultz, R.M.

    1990-04-01

    The Oak Ridge National Laboratory (ORNL) is a multipurpose Research and Development (R D) facility. These R D activities generate numerous small waste streams. Waste minimization is defined as any action that minimizes the volume or toxicity of waste by avoiding its generation or recycling. This is accomplished by material substitution, changes to processes, or recycling wastes for reuse. Waste reduction is defined as waste minimization plus treatment which results in volume or toxicity reduction. The ORNL Waste Reduction Program will include both waste minimization and waste reduction efforts. Federal regulations, DOE policies and guidelines, increased costs and liabilities associatedmore » with the management of wastes, limited disposal options and facility capacities, and public consciousness have been motivating factors for implementing comprehensive waste reduction programs. DOE Order 5820.2A, Section 3.c.2.4 requires DOE facilities to establish an auditable waste reduction program for all LLW generators. In addition, it further states that any new facilities, or changes to existing facilities, incorporate waste minimization into design considerations. A more recent DOE Order, 3400.1, Section 4.b, requires the preparation of a waste reduction program plan which must be reviewed annually and updated every three years. Implementation of a waste minimization program for hazardous and radioactive mixed wastes is sited in DOE Order 5400.3, Section 7.d.5. This document has been prepared to address these requirements. 6 refs., 1 fig., 2 tabs.« less

  4. Pyrite oxidation and reduction - Molecular orbital theory considerations. [for geochemical redox processes

    NASA Technical Reports Server (NTRS)

    Luther, George W., III

    1987-01-01

    In this paper, molecular orbital theory is used to explain a heterogeneous reaction mechanism for both pyrite oxidation and reduction. The mechanism demonstrates that the oxidation of FeS2 by Fe(3+) may occur as a result of three important criteria: (1) the presence of a suitable oxidant having a vacant orbital (in case of liquid phase) or site (solid phase) to bind to the FeS2 via sulfur; (2) the initial formation of a persulfido (disulfide) bridge between FeS2 and the oxidant, and (3) an electron transfer from a pi(asterisk) orbital in S2(2-) to a pi or pi(asterisk) orbital of the oxidant.

  5. Flavins secreted by bacterial cells of Shewanella catalyze cathodic oxygen reduction.

    PubMed

    Liu, Huan; Matsuda, Shoichi; Hashimoto, Kazuhito; Nakanishi, Shuji

    2012-06-01

    On Her Majesty's Secrete Service: Oxygen reduction is an important process for microbial fuel cells (MFCs) and microbiologically-influenced corrosion (MIC). We demonstrate that flavins secreted by anode-respiring Shewanella cells can catalyze cathodic oxygen reduction via adsorption on the cathode. The findings will provide new insight for developing methods to improve MFC performance and to prevent MIC. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Pathway of FeEDTA transformation and its impact on performance of NOx removal in a chemical absorption-biological reduction integrated process

    PubMed Central

    Li, Wei; Zhao, Jingkai; Zhang, Lei; Xia, Yinfeng; Liu, Nan; Li, Sujing; Zhang, Shihan

    2016-01-01

    A novel chemical absorption-biological reduction (CABR) integrated process, employing ferrous ethylenediaminetetraacetate (Fe(II)EDTA) as a solvent, is deemed as a potential option for NOx removal from the flue gas. Previous work showed that the Fe(II)EDTA concentration was critical for the NOx removal in the CABR process. In this work, the pathway of FeEDTA (Fe(III)/Fe(II)-EDTA) transformation was investigated to assess its impact on the NOx removal in a biofilter. Experimental results revealed that the FeEDTA transformation involved iron precipitation and EDTA degradation. X-ray photoelectron spectroscopy analysis confirmed the iron was precipitated in the form of Fe(OH)3. The iron mass balance analysis showed 44.2% of the added iron was precipitated. The EDTA degradation facilitated the iron precipitation. Besides chemical oxidation, EDTA biodegradation occurred in the biofilter. The addition of extra EDTA helped recover the iron from the precipitation. The transformation of FeEDTA did not retard the NO removal. In addition, EDTA rather than the iron concentration determined the NO removal efficiency. PMID:26743930

  7. Reduction in Force: Is Your Board Prepared?

    ERIC Educational Resources Information Center

    Kudlaty, Frank

    One of the conditions set forth in the hiring of the new superintendent of a southeast Texas school district was that a reduction in force would be accomplished. How this process, that usually involves six months planning time and and additional year to carry out, was accomplished in a period of six months is detailed in this speech. An analysis…

  8. SEL's Software Process-Improvement Program

    NASA Technical Reports Server (NTRS)

    Basili, Victor; Zelkowitz, Marvin; McGarry, Frank; Page, Jerry; Waligora, Sharon; Pajerski, Rose

    1995-01-01

    The goals and operations of the Software Engineering Laboratory (SEL) is reviewed. For nearly 20 years the SEL has worked to understand, assess, and improve software and the development process within the production environment of the Flight Dynamics Division (FDD) of NASA's Goddard Space Flight Center. The SEL was established in 1976 with the goals of reducing: (1) the defect rate of delivered software, (2) the cost of software to support flight projects, and (3) the average time to produce mission-support software. After studying over 125 projects of FDD, the results have guided the standards, management practices, technologies, and the training within the division. The results of the studies have been a 75 percent reduction in defects, a 50 percent reduction in cost, and a 25 percent reduction in development time. Over time the goals of SEL have been clarified. The goals are now stated as: (1) Understand baseline processes and product characteristics, (2) Assess improvements that have been incorporated into the development projects, (3) Package and infuse improvements into the standard SEL process. The SEL improvement goal is to demonstrate continual improvement of the software process by carrying out analysis, measurement and feedback to projects with in the FDD environment. The SEL supports the understanding of the process by study of several processes including, the effort distribution, and error detection rates. The SEL assesses and refines the processes. Once the assessment and refinement of a process is completed, the SEL packages the process by capturing the process in standards, tools and training.

  9. Noise reduction and image enhancement using a hardware implementation of artificial neural networks

    NASA Astrophysics Data System (ADS)

    David, Robert; Williams, Erin; de Tremiolles, Ghislain; Tannhof, Pascal

    1999-03-01

    In this paper, we present a neural based solution developed for noise reduction and image enhancement using the ZISC, an IBM hardware processor which implements the Restricted Coulomb Energy algorithm and the K-Nearest Neighbor algorithm. Artificial neural networks present the advantages of processing time reduction in comparison with classical models, adaptability, and the weighted property of pattern learning. The goal of the developed application is image enhancement in order to restore old movies (noise reduction, focus correction, etc.), to improve digital television images, or to treat images which require adaptive processing (medical images, spatial images, special effects, etc.). Image results show a quantitative improvement over the noisy image as well as the efficiency of this system. Further enhancements are being examined to improve the output of the system.

  10. Microbiological reduction of Sb(V) in anoxic freshwater sediments

    USGS Publications Warehouse

    Oremland, Ronald S.; Kulp, Thomas R.; Miller, Laurence G.; Braiotta, Franco; Webb, Samuel M.; Kocar, Benjamin D; Blum, Jodi S.

    2014-01-01

    Microbiological reduction of millimolar concentrations of Sb(V) to Sb(III) was observed in anoxic sediments from two freshwater settings: (1) a Sb- and As-contaminated mine site (Stibnite Mine) in central Idaho and 2) an uncontaminated suburban lake (Searsville Lake) in the San Francisco Bay Area. Rates of Sb(V) reduction in anoxic sediment microcosms and enrichment cultures were enhanced by amendment with lactate or acetate as electron donors but not by H2, and no reduction occurred in sterilized controls. Addition of 2-14C-acetate to Stibnite Mine microcosms resulted in the production of 14CO2 coupled to Sb(V) reduction, suggesting that this process proceeds by a dissimilatory respiratory pathway in those sediments. Antimony(V) reduction in Searsville Lake sediments was not coupled to acetate mineralization and may be associated with Sb-resistance. The microcosms and enrichment cultures also reduced sulfate, and the precipitation of insoluble Sb(III)-sulfide complexes was a major sink for reduced Sb. The reduction of Sb(V) by Stibnite Mine sediments was inhibited by As(V), suggesting that As(V) is a preferred electron acceptor for the indigenous community. These findings indicate a novel pathway for anaerobic microbiological respiration and suggest that communities capable of reducing high concentrations of Sb(V) commonly occur naturally in the environment.

  11. A feasibility study for high-temperature titanium reduction from TiCl4 using a magnesiothermic process

    NASA Astrophysics Data System (ADS)

    Ivanov, S. L.; Zablotsky, D.

    2018-05-01

    The current industrial practice for titanium extraction is a complex procedure, which produces a porous reaction mass of sintered titanium particulates fused to a steel retort wall with magnesium and MgCl2 trapped in the interstices. The reactor temperature is limited to approx. 900 °C due to the formation of fusible TiFe eutectic, which corrodes the retort and degrades the quality of titanium sponge. Here we examine the theoretical foundations and technological possibilities to design a shielded retort of niobium-zirconium alloy NbZr(1%), which is resistant to corrosion by titanium at high temperature. We consider the reactor at a temperature of approx. 1150 °C. Supplying stoichiometric quantities of reagents enables the reaction in the gas phase, whereas the exothermic process sustains the combustion of the reaction zone. When the pathway to the condenser is open, vacuum separation and evacuation of vaporized magnesium dichloride and excess magnesium into the water-cooled condenser take place. As both the reaction and the evacuation occur within seconds, the yield of the extraction is improved. We anticipate new possibilities for designing a device combining the retort function to conduct the reduction in the gas phase with fast vacuum separation of the reaction products and distillation of magnesium dichloride.

  12. Deposition of silver nanoparticles on multiwalled carbon nanotubes by chemical reduction process and their antimicrobial effects

    NASA Astrophysics Data System (ADS)

    Haider, Adawiya J.; Thamir, Amin D.; Ahmed, Duha S.; Mohammad, M. R.

    2016-07-01

    In this paper, the functionalization of raw-MWCNTs involves oxidation reaction using concentrated acid mixture of HNO3:H2SO4 (1:3), via ultrasonic bath (170 W, 50 kHz) to obtain functional groups. Then Ag nanoparticles are decorated the outside over the surface of functionalized MWCNTs using a chemical reduction process resulting in the formation of(Ag/ MWCNTs) hybrid material. The results showed that outer diameter functionalized F-MWCNTs andAg nanoparticles size was about (11-80) nm and (10 to 25) nm, respectively using TEM and HRTEM. The crystallographic structure of MWCNTs using X-ray diffraction (XRD) analysis proved diffraction peaks at 38.1°, 44.3°, 64.7° and 77.4° degrees namely, Ag (111), Ag (200), Ag (220), and Ag (311) of the face-centered cubic lattice of Ag, respectively, excepting the peak at 2θ =25.6°, which correspond to the (0 0 2) reflection of the MWNTs are corresponding to Ag/MWNTs. The antimicrobial activities of Ag/MWCNTs hybrid using plate count method showed that decreasing a large number of bacteria colonies of E. coli and S. aureu with increasing the hybrid concentrations after incubation for 24h in shaker incubator with percentage of inhibition approaching 100%.

  13. Direct Reduction of Ferrous Oxides to form an Iron-Rich Alternative Charge Material

    NASA Astrophysics Data System (ADS)

    Ünal, H. İbrahim; Turgut, Enes; Atapek, Ş. H.; Alkan, Attila

    2015-12-01

    In this study, production of sponge iron by direct reduction of oxides and the effect of reductant on metallization were investigated. In the first stage of the study, scale formed during hot rolling of slabs was reduced in a rotating furnace using solid and gas reductants. Coal was used as solid reductant and hydrogen released from the combustion reaction of LNG was used as the gas one. The sponge iron produced by direct reduction was melted and solidified. In the second stage, Hematite ore in the form of pellets was reduced using solid carbon in a furnace heated up to 1,100°C for 60 and 120 minutes. Reduction degree of process was evaluated as a function of time and the ratio of Cfix/Fetotal. In the third stage, final products were examined using scanning electron microscope and microanalysis was carried out by energy dispersive x-ray spectrometer attached to the electron microscope. It is concluded that (i) direct reduction using both solid and gas reductants caused higher metallization compared to using only solid reductant, (ii) as the reduction time and ratio of Cfix/Fetotal increased %-reduction of ore increased.

  14. BENCH-SCALE PROCESS EVALUATION OF REBURNING AND SORBENT INJECTION FOR IN-FURNACE NOX/SOX REDUCTION

    EPA Science Inventory

    The report gives results of combining reburning with the injection of calcium-based sorbents to investigate the potential for combined NOx and SOx reduction. Reburning, applied to pulverized-coal-fired utility boilers, involves injecting a secondary fuel above the main firing zon...

  15. Controller design for wind turbine load reduction via multiobjective parameter synthesis

    NASA Astrophysics Data System (ADS)

    Hoffmann, A. F.; Weiβ, F. A.

    2016-09-01

    During the design process for a wind turbine load reduction controller many different, sometimes conflicting requirements must be fulfilled simultaneously. If the requirements can be expressed as mathematical criteria, such a design problem can be solved by a criterion-vector and multi-objective design optimization. The software environment MOPS (Multi-Objective Parameter Synthesis) supports the engineer for such a design optimization. In this paper MOPS is applied to design a multi-objective load reduction controller for the well-known DTU 10 MW reference wind turbine. A significant reduction in the fatigue criteria especially the blade damage can be reached by the use of an additional Individual Pitch Controller (IPC) and an additional tower damper. This reduction is reached as a trade-off with an increase of actuator load.

  16. Vehicle Lightweighting: Mass Reduction Spectrum Analysis and Process Cost Modeling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mascarin, Anthony; Hannibal, Ted; Raghunathan, Anand

    2016-03-01

    The U.S. Department of Energy’s Vehicle Technologies Office, Materials area commissioned a study to model and assess manufacturing economics of alternative design and production strategies for a series of lightweight vehicle concepts. In the first two phases of this effort examined combinations of strategies aimed at achieving strategic targets of 40% and a 45% mass reduction relative to a standard North American midsize passenger sedan at an effective cost of $3.42 per pound (lb) saved. These results have been reported in the Idaho National Laboratory report INL/EXT-14-33863 entitled Vehicle Lightweighting: 40% and 45% Weight Savings Analysis: Technical Cost Modeling formore » Vehicle Lightweighting published in March 2015. The data for these strategies were drawn from many sources, including Lotus Engineering Limited and FEV, Inc. lightweighting studies, U.S. Department of Energy-funded Vehma International of America, Inc./Ford Motor Company Multi-Material Lightweight Prototype Vehicle Demonstration Project, the Aluminum Association Transportation Group, many United States Council for Automotive Research’s/United States Automotive Materials Partnership LLC lightweight materials programs, and IBIS Associates, Inc.’s decades of experience in automotive lightweighting and materials substitution analyses.« less

  17. Development and Validation of a Model for Hydrogen Reduction of JSC-1A

    NASA Technical Reports Server (NTRS)

    Hegde, U.; Balasubramaniam, R.; Gokoglu, S.

    2009-01-01

    Hydrogen reduction of lunar regolith has been proposed as a viable technology for oxygen production on the moon. Hydrogen reduces FeO present in the lunar regolith to form metallic iron and water. The water may be electrolyzed to recycle the hydrogen and produce oxygen. Depending upon the regolith composition, FeO may be bound to TiO2 as ilmenite or it may be dispersed in glassy substrates. Some testing of hydrogen reduction has been conducted with Apollo-returned lunar regolith samples. However, due to the restricted amount of lunar material available for testing, detailed understanding and modeling of the reduction process in regolith have not yet been developed. As a step in this direction, hydrogen reduction studies have been carried out in more detail with lunar regolith simulants such as JSC-1A by NASA and other organizations. While JSC-1A has some similarities with lunar regolith, it does not duplicate the wide variety of regolith types on the moon, for example, it contains almost no ilmenite. Nonetheless, it is a good starting point for developing an understanding of the hydrogen reduction process with regolith-like material. In this paper, a model utilizing a shrinking core formulation coupled with the reactor flow is described and validated against experimental data on hydrogen reduction of JSC-1A.

  18. Human Factor Investigation of Waste Processing System During the HI-SEAS 4 Month Mars Analog Mission in Support of NASA's Logistic Reduction and Repurposing Project: Trash to Gas

    NASA Technical Reports Server (NTRS)

    Caraccio, Anne; Hintze, Paul; Miles, John D.

    2014-01-01

    NASAs Logistics Reduction and Repurposing (LRR) project is a collaborative effort in which NASA is tasked with reducing total logistical mass through reduction, reuse and recycling of various wastes and components of long duration space missions and habitats. Trash to Gas (TtG) is a sub task to LRR with efforts focused on development of a technology that converts wastes generated during long duration space missions into high-value products such as methane, water for life support, raw material production feedstocks, and other energy sources. The reuse of discarded materials is a critical component to reducing overall mission mass. The 120 day Hawaii Space Exploration and Analog Simulation provides a unique opportunity to answer questions regarding crew interface and system analysis for designing and developing future flight-like versions of a TtG system. This paper will discuss the human factors that would affect the design of a TtG or other waste processing systems. An overview of the habitat, utility usage, and waste storage and generation is given. Crew time spent preparing trash for TtG processing was recorded. Gas concentrations were measured near the waste storage locations and at other locations in the habitat. In parallel with the analog mission, experimental processing of waste materials in a TtG reactor was performed in order to evaluate performance with realistic waste materials.

  19. Human Factor Investigation of Waste Processing System During the HI-SEAS 4-month Mars Analog Mission in Support of NASA's Logistic Reduction and Repurposing Project: Trash to Gas

    NASA Technical Reports Server (NTRS)

    Caraccio, Anne; Hintze, Paul E.; Miles, John D.

    2014-01-01

    NASA's Logistics Reduction and Repurposing (LRR) project is a collaborative effort in which NASA is tasked with reducing total logistical mass through reduction, reuse and recycling of various wastes and components of long duration space missions and habitats. Trash to Gas (TtG) is a sub task to LRR with efforts focused on development of a technology that converts wastes generated during long duration space missions into high-value products such as methane, water for life support, raw material production feedstocks, and other energy sources. The reuse of discarded materials is a critical component to reducing overall mission mass. The 120 day Hawaii Space Exploration and Analog Simulation provides a unique opportunity to answer questions regarding crew interface and system analysis for designing and developing future flight-like versions of a TtG system. This paper will discuss the human factors that would affect the design of a TtG or other waste processing systems. An overview of the habitat, utility usage, and waste storage and generation is given. Crew time spent preparing trash for TtG processing was recorded. Gas concentrations were measured near the waste storage locations and at other locations in the habitat. In parallel with the analog mission, experimental processing of waste materials in a TtG reactor was performed in order to evaluate performance with realistic waste materials.

  20. Stacked competitive networks for noise reduction in low-dose CT

    PubMed Central

    Du, Wenchao; Chen, Hu; Wu, Zhihong; Sun, Huaiqiang; Liao, Peixi

    2017-01-01

    Since absorption of X-ray radiation has the possibility of inducing cancerous, genetic and other diseases to patients, researches usually attempt to reduce the radiation dose. However, reduction of the radiation dose associated with CT scans will unavoidably increase the severity of noise and artifacts, which can seriously affect diagnostic confidence. Due to the outstanding performance of deep neural networks in image processing, in this paper, we proposed a Stacked Competitive Network (SCN) approach to noise reduction, which stacks several successive Competitive Blocks (CB). The carefully handcrafted design of the competitive blocks was inspired by the idea of multi-scale processing and improvement the network’s capacity. Qualitative and quantitative evaluations demonstrate the competitive performance of the proposed method in noise suppression, structural preservation, and lesion detection. PMID:29267360

  1. Particle size reduction of propellants by cryocycling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Whinnery, L.; Griffiths, S.; Lipkin, J.

    1995-05-01

    Repeated exposure of a propellant to liquid nitrogen causes thermal stress gradients within the material resulting in cracking and particle size reduction. This process is termed cryocycling. The authors conducted a feasibility study, combining experiments on both inert and live propellants with three modeling approaches. These models provided optimized cycle times, predicted ultimate particle size, and allowed crack behavior to be explored. Process safety evaluations conducted separately indicated that cryocycling does not increase the sensitivity of the propellants examined. The results of this study suggest that cryocycling is a promising technology for the demilitarization of tactical rocket motors.

  2. METAL PLATING PROCESS

    DOEpatents

    Walker, D.E.; Noland, R.A.

    1958-08-12

    A process ts described for obtaining a closely bonded coating of steel or iron on uranium. The process consists of providing, between the steel and uramium. a layer of silver. amd then pressure rolling tbe assembly at about 600 deg C until a reduction of from l0 to 50% has been obtained.

  3. Cryogenic Treatment of Al-Li Alloys for Improved Weldability, Repairability, and Reduction of Residual Stresses

    NASA Technical Reports Server (NTRS)

    Malone, Tina W.; Graham, Benny F.; Gentz, Steven J. (Technical Monitor)

    2001-01-01

    Service performance has shown that cryogenic treatment of some metals provides improved strength, fatigue life, and wear resistance to the processed material. Effects such as these were initially discovered by NASA engineers while evaluating spacecraft that had returned from the cold vacuum of space. Factors such as high cost, poor repairability, and poor machinability are currently prohibitive for wide range use of some aerospace aluminum alloys. Application of a cryogenic treatment process to these alloys is expected provide improvements in weldability and weld properties coupled with a reduction in repairs resulting in a significant reduction in the cost to manufacture and life cycle cost of aerospace hardware. The primary purpose of this effort was to evaluate the effects of deep cryogenic treatment of some aluminum alloy plate products, welds, and weld repairs, and optimize a process for the treatment of these materials. The optimized process is being evaluated for improvements in properties of plate and welds, improvements in weldability and repairability of treated materials, and as an alternative technique for the reduction of residual stresses in repaired welds. This paper will present the results of testing and evaluation conducted in this effort. These results will include assessments of changes in strength, toughness, stress corrosion susceptability, weldability, repairability, and reduction in residual stresses of repaired welds.

  4. Integrative harm reduction psychotherapy: a case of substance use, multiple trauma, and suicidality.

    PubMed

    Tatarsky, Andrew; Kellogg, Scott

    2010-02-01

    Harm reduction is a new paradigm that seeks to reduce the harmful consequences of substance use and other risky behaviors without requiring abstinence. This article discusses integrative harm reduction psychotherapy, one application of harm reduction principles to psychotherapy. Seven therapeutic tasks are described with attention to clinical process, skills, and strategies. A case is presented that illustrates the application of this approach with life-threatening substance use that was related to multiple trauma and suicidal depression. (c) 2010 Wiley Periodicals, Inc.

  5. Experimental understanding of the viscosity reduction ability of TLCPs with different PEs

    NASA Astrophysics Data System (ADS)

    Tang, Youhong; Zuo, Min; Gao, Ping

    2014-08-01

    In this study, two thermotropic liquid crystalline polyesters (TLCPs) synthesized by polycondensation of p-hydroxybenzoic acid /hydroquinone/ poly dicarboxylic acid were used as viscosity reduction agents for polyethylene (PE). The TLCPs had different thermal, rheological and other physical properties that were quantitatively characterized. The two TLCPs were blended with high density PE (HDPE) and high molecular mass PE (HMMPE) by simple twin screw extrusion under the same weight ratio of 1.0 wt% and were each rheologically characterized at 190°C. The TLCPs acted as processing modifiers for the PEs and the bulk viscosity of the blends decreased dramatically. However, the viscosity reduction ability was not identical: one TLCP had obviously higher viscosity reduction ability on the HDPE, with a maximum viscosity reduction ratio of 68.1%, whereas the other TLCP had higher viscosity reduction ability on the HMMPE, with a maximum viscosity reduction ratio of 98.7%. Proposed explanations for these differences are evaluated.

  6. A mature Bosch CO2 reduction technology. [for long-duration space missions

    NASA Technical Reports Server (NTRS)

    King, C. D.; Holmes, R. F.

    1976-01-01

    The reduction of CO2 is one of the steps in closing the oxygen loop for long-duration manned space missions. Several units utilizing the Bosch process, which catalytically reduces CO2 with hydrogen, have been built and operated during the past decade. Each contributed substantial information affecting subsequent designs. Early challenges were primarily concerned with carbon control, materials durability, and reliability of reaction initiation. These were followed by concern about power consumption, expendable weight, volume, and process rate control. Suitable materials and techniques for carbon containment and process reliability have been demonstrated. Power requirements have been reduced by almost an order of magnitude. Methods for significant reductions in expendable weight and volume have been developed. The technology is at a state of maturity directly applicable to designs for space missions.

  7. Youpi: YOUr processing PIpeline

    NASA Astrophysics Data System (ADS)

    Monnerville, Mathias; Sémah, Gregory

    2012-03-01

    Youpi is a portable, easy to use web application providing high level functionalities to perform data reduction on scientific FITS images. Built on top of various open source reduction tools released to the community by TERAPIX (http://terapix.iap.fr), Youpi can help organize data, manage processing jobs on a computer cluster in real time (using Condor) and facilitate teamwork by allowing fine-grain sharing of results and data. Youpi is modular and comes with plugins which perform, from within a browser, various processing tasks such as evaluating the quality of incoming images (using the QualityFITS software package), computing astrometric and photometric solutions (using SCAMP), resampling and co-adding FITS images (using SWarp) and extracting sources and building source catalogues from astronomical images (using SExtractor). Youpi is useful for small to medium-sized data reduction projects; it is free and is published under the GNU General Public License.

  8. Cocatalysts in Semiconductor-based Photocatalytic CO2 Reduction: Achievements, Challenges, and Opportunities.

    PubMed

    Ran, Jingrun; Jaroniec, Mietek; Qiao, Shi-Zhang

    2018-02-01

    Ever-increasing fossil-fuel combustion along with massive CO 2 emissions has aroused a global energy crisis and climate change. Photocatalytic CO 2 reduction represents a promising strategy for clean, cost-effective, and environmentally friendly conversion of CO 2 into hydrocarbon fuels by utilizing solar energy. This strategy combines the reductive half-reaction of CO 2 conversion with an oxidative half reaction, e.g., H 2 O oxidation, to create a carbon-neutral cycle, presenting a viable solution to global energy and environmental problems. There are three pivotal processes in photocatalytic CO 2 conversion: (i) solar-light absorption, (ii) charge separation/migration, and (iii) catalytic CO 2 reduction and H 2 O oxidation. While significant progress is made in optimizing the first two processes, much less research is conducted toward enhancing the efficiency of the third step, which requires the presence of cocatalysts. In general, cocatalysts play four important roles: (i) boosting charge separation/transfer, (ii) improving the activity and selectivity of CO 2 reduction, (iii) enhancing the stability of photocatalysts, and (iv) suppressing side or back reactions. Herein, for the first time, all the developed CO 2 -reduction cocatalysts for semiconductor-based photocatalytic CO 2 conversion are summarized, and their functions and mechanisms are discussed. Finally, perspectives in this emerging area are provided. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Logistics Reduction Technologies for Exploration Missions

    NASA Technical Reports Server (NTRS)

    Broyan, James L., Jr.; Ewert, Michael K.; Fink, Patrick W.

    2014-01-01

    Human exploration missions under study are limited by the launch mass capacity of existing and planned launch vehicles. The logistical mass of crew items is typically considered separate from the vehicle structure, habitat outfitting, and life support systems. Although mass is typically the focus of exploration missions, due to its strong impact on launch vehicle and habitable volume for the crew, logistics volume also needs to be considered. NASA's Advanced Exploration Systems (AES) Logistics Reduction and Repurposing (LRR) Project is developing six logistics technologies guided by a systems engineering cradle-to-grave approach to enable after-use crew items to augment vehicle systems. Specifically, AES LRR is investigating the direct reduction of clothing mass, the repurposing of logistical packaging, the use of autonomous logistics management technologies, the processing of spent crew items to benefit radiation shielding and water recovery, and the conversion of trash to propulsion gases. Reduction of mass has a corresponding and significant impact to logistical volume. The reduction of logistical volume can reduce the overall pressurized vehicle mass directly, or indirectly benefit the mission by allowing for an increase in habitable volume during the mission. The systematic implementation of these types of technologies will increase launch mass efficiency by enabling items to be used for secondary purposes and improve the habitability of the vehicle as mission durations increase. Early studies have shown that the use of advanced logistics technologies can save approximately 20 m(sup 3) of volume during transit alone for a six-person Mars conjunction class mission.

  10. Dimension reduction method for SPH equations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tartakovsky, Alexandre M.; Scheibe, Timothy D.

    2011-08-26

    Smoothed Particle Hydrodynamics model of a complex multiscale processe often results in a system of ODEs with an enormous number of unknowns. Furthermore, a time integration of the SPH equations usually requires time steps that are smaller than the observation time by many orders of magnitude. A direct solution of these ODEs can be extremely expensive. Here we propose a novel dimension reduction method that gives an approximate solution of the SPH ODEs and provides an accurate prediction of the average behavior of the modeled system. The method consists of two main elements. First, effective equationss for evolution of averagemore » variables (e.g. average velocity, concentration and mass of a mineral precipitate) are obtained by averaging the SPH ODEs over the entire computational domain. These effective ODEs contain non-local terms in the form of volume integrals of functions of the SPH variables. Second, a computational closure is used to close the system of the effective equations. The computational closure is achieved via short bursts of the SPH model. The dimension reduction model is used to simulate flow and transport with mixing controlled reactions and mineral precipitation. An SPH model is used model transport at the porescale. Good agreement between direct solutions of the SPH equations and solutions obtained with the dimension reduction method for different boundary conditions confirms the accuracy and computational efficiency of the dimension reduction model. The method significantly accelerates SPH simulations, while providing accurate approximation of the solution and accurate prediction of the average behavior of the system.« less

  11. Noise reduction techniques for Bayer-matrix images

    NASA Astrophysics Data System (ADS)

    Kalevo, Ossi; Rantanen, Henry

    2002-04-01

    In this paper, some arrangements to apply Noise Reduction (NR) techniques for images captured by a single sensor digital camera are studied. Usually, the NR filter processes full three-color component image data. This requires that raw Bayer-matrix image data, available from the image sensor, is first interpolated by using Color Filter Array Interpolation (CFAI) method. Another choice is that the raw Bayer-matrix image data is processed directly. The advantages and disadvantages of both processing orders, before (pre-) CFAI and after (post-) CFAI, are studied with linear, multi-stage median, multistage median hybrid and median-rational filters .The comparison is based on the quality of the output image, the processing power requirements and the amount of memory needed. Also the solution, which improves preservation of details in the NR filtering before the CFAI, is proposed.

  12. Reduction of sludge production from WWTP using thermal pretreatment and enhanced anaerobic methanisation.

    PubMed

    Graja, S; Chauzy, J; Fernandes, P; Patria, L; Cretenot, D

    2005-01-01

    The objective of the study presented here was to investigate the performance of an enhanced two-step anaerobic process for the treatment of WWTP sludge. This process was developed to answer the urgent need currently faced by WWTP operators to reduce the production of biosolids, for which disposal pathways are facing increasing difficulties. A pilot plant was operated on a full-scale WWTP (2,500 p.e.) over a period of 4 months. It consisted of a thermal pre-treatment of excess sludge at 175 degrees C and 40 min, followed by dewatering and methanisation of the centrate in a fixed-film reactor. The thermal lysis had a two-fold enhancing effect on sludge reduction efficiency: firstly, it allowed a decrease of the HRT in the methaniser to 2.9 days and secondly, it yielded biosolids with a high dewaterability. This contributed to further reductions in the final volume of sludge to be disposed of. The two-step process achieved a sludge reduction efficiency of 65% as TSS, thus giving an interesting treatment option for WWTP facing sludge disposal problems.

  13. Multi-scale study on process of contravariant and covariant polymer elongation and drag reduction in viscoelastic turbulence

    NASA Astrophysics Data System (ADS)

    Horiuti, Kiyosi; Suzuki, Shu

    2014-11-01

    We study the elongation process of polymers released in the Newtonian homogeneous isotropic turbulence by connecting a mesoscopic description of ensemble of elastic dumbbells using Brownian dynamics (BDS) to the macroscopic description for the fluid using DNS. The dumbbells are allowed to be advected non-affinely with the macroscopically-imposed deformation. More drastic drag reduction is achieved when non-affinity is maximum than in the complete affine case. In the former case, the dumbbell is convected as a covariant vector, and in the latter as a contravariant vector. We derive the exact solution for the governing equation of the motion of dumbbells. The maximum stretching of dumbbell is achieved when the dumbbell aligns in the direction of vorticity in the contravariant case, and when the dumbbell directs outward perpendicularly on the vortex sheet in the covariant case. Alignment in the BDS-DNS data agrees with the theoretical results. In the mixture of contravariant and covariant dumbbells, the covariant dumbbells are transversely aligned with the contravariant dumbbells. Compared with the cases without mixture, stretching of covariant dumbbell is enhanced, while that of contravariant dumbbell is reduced. Application of this phenomenon is discussed.

  14. Paediatric x-ray radiation dose reduction and image quality analysis.

    PubMed

    Martin, L; Ruddlesden, R; Makepeace, C; Robinson, L; Mistry, T; Starritt, H

    2013-09-01

    Collaboration of multiple staff groups has resulted in significant reduction in the risk of radiation-induced cancer from radiographic x-ray exposure during childhood. In this study at an acute NHS hospital trust, a preliminary audit identified initial exposure factors. These were compared with European and UK guidance, leading to the introduction of new factors that were in compliance with European guidance on x-ray tube potentials. Image quality was assessed using standard anatomical criteria scoring, and visual grading characteristics analysis assessed the impact on image quality of changes in exposure factors. This analysis determined the acceptability of gradual radiation dose reduction below the European and UK guidance levels. Chest and pelvis exposures were optimised, achieving dose reduction for each age group, with 7%-55% decrease in critical organ dose. Clinicians confirmed diagnostic image quality throughout the iterative process. Analysis of images acquired with preliminary and final exposure factors indicated an average visual grading analysis result of 0.5, demonstrating equivalent image quality. The optimisation process and final radiation doses are reported for Carestream computed radiography to aid other hospitals in minimising radiation risks to children.

  15. ExMC Work Prioritization Process

    NASA Technical Reports Server (NTRS)

    Simon, Matthew

    2015-01-01

    Last year, NASA's Human Research Program (HRP) introduced the concept of a "Path to Risk Reduction" (PRR), which will provide a roadmap that shows how the work being done within each HRP element can be mapped to reducing or closing exploration risks. Efforts are currently underway within the Exploration Medical Capability (ExMC) Element to develop a structured, repeatable process for prioritizing work utilizing decision analysis techniques and risk estimation tools. The goal of this effort is to ensure that the work done within the element maximizes risk reduction for future exploration missions in a quantifiable way and better aligns with the intent and content of the Path to Risk Reduction. The Integrated Medical Model (IMM) will be used to identify those conditions that are major contributors of medical risk for a given design reference mission. For each of these conditions, potential prevention, screening, diagnosis, and treatment methods will be identified. ExMC will then aim to prioritize its potential investments in these mitigation methods based upon their potential for risk reduction and other factors such as vehicle performance impacts, near term schedule needs, duplication with external efforts, and cost. This presentation will describe the process developed to perform this prioritization and inform investment discussions in future element planning efforts. It will also provide an overview of the required input information, types of process participants, figures of merit, and the expected outputs of the process.

  16. Reductive dechlorination of chlorinated ethenes under oxidation-reduction conditions and potentiometric surfaces in two trichloroethene-contaminated zones at the Double Eagle and Fourth Street Superfund sites in Oklahoma City, Oklahoma

    USGS Publications Warehouse

    Braun, Christopher L.

    2004-01-01

    The Double Eagle Refining Superfund site and the Fourth Street Abandoned Refinery Superfund site are in northeast Oklahoma City, Oklahoma, adjacent to one another. The Double Eagle facility became a Superfund site on the basis of contamination from lead and volatile organic compounds; the Fourth Street facility on the basis of volatile organic compounds, pesticides, and acid-base neutral compounds. The study documented in this report was done to investigate whether reductive dechlorination of chlorinated ethenes under oxidation-reduction conditions is occurring in two zones of the Garber-Wellington aquifer (shallow zone 30–60 to 75 feet below land surface, deep zone 75 to 160 feet below land surface) at the sites; and to construct potentiometric surfaces of the two water-yielding zones to determine the directions of groundwater flow at the sites. The presence in some wells of intermediate products of reductive dechlorination, dichloroethene and vinyl chloride, is an indication that reductive dechlorination of trichloroethene is occurring. Dissolved oxygen concentrations (less than 0.5 milligram per liter) indicate that consumption of dissolved oxygen likely had occurred in the oxygen-reducing microbial process associated with reductive dechlorination. Concentrations of nitrate and nitrite nitrogen (generally less than 2.0 and 0.06 milligrams per liter, respectively) indicate that nitrate reduction probably is not a key process in either aquifer zone. Concentrations of ferrous iron greater than 1.00 milligram per liter in the majority of wells sampled indicate that iron reduction is probable. Concentrations of sulfide less than 0.05 milligram per liter in all wells indicate that sulfate reduction probably is not a key process in either zone. The presence of methane in ground water is an indication of strongly reducing conditions that facilitate reductive dechlorination. Methane was detected in all but one well. In the shallow zone in the eastern part of the study

  17. A preliminary study on the reduction of limonite ore by using rice husk as a reducing agent

    NASA Astrophysics Data System (ADS)

    Maksum, Ahmad; Husein, Michael Kelvin E.; Permana, Sulaksana; Rustandi, Andi; Wahyuadi Soedarsono, Johny

    2018-03-01

    The abundant of rice husk in Indonesia has encouraged researchers to study the feasibility of rice husk for substituting material that is more expensive or dangerous. In previous study, silica with a purity of 99.9% has been obtained from rice husk with calcinations process. Nevertheless, the gases resulting from the process were not used and left useless. Therefore, in this study, those gases derived from rice husk calcinations process were used as reducing agents during the ferronickel (Fe-Ni) production through a direct reduction process. The objective of this study was to investigate the effect of the amount of rice husk in the pellets on the increase of nickel content in the limonite reduction process. The limonite ore were crushed to the size of less than 150 mesh using disc-mill, and then were mixed with rice husk powder (10, 20, 30 in wt % mass) before being pelletized using bentonite as a binder. The resulted pellets were roasted at 500°C for 60 minutes and then quenched in water media. After drying process, the reduction process of 40g pellets was conducted at 1000°C for 90 minutes with 20g rice husk in furnace. The effects of additional rice husk on the direct reduction of limonite ore pellets were qualitatively analyzed by using X-ray powder diffraction (XRD) and quantitatively by Atomic absorption spectroscopy (AAS). Both analysis results showed that the reduction process followed the reaction scheme: Fe2O3→Fe3O4→FeO and NiO phase was detected in the sample with 20% rice husk addition. The optimum concentration of Ni 1.23% was obtained for 20% rice husk addition.

  18. Raw hematite based Fe(III) bio-reduction process for humified landfill leachate treatment.

    PubMed

    Li, Rui; Jiang, Yu; Xi, Beidou; Li, Mingxiao; Meng, Xiaoguang; Feng, Chuanping; Mao, Xuhui; Liu, Hongliang; Jiang, Yonghai

    2018-05-03

    Microorganisms from paddy soils and raw hematite are used for enhancing natural Fe(III) bio-reduction, in order to remove macromolecular organic pollutants from humified landfill leachate. Based on batch experiments, 60% of refractory organics can be adsorbed by hematite in 12 days. In the presence of Fe(III)-reducing bacteria, 489.60 ± 0.14 mg L -1 of dissolved organic matters can be degraded to 51.90 ± 3.96 mg L -1 within 50 days; twelve types of semi volatile organic compounds can be degraded; hereby, the reaction follows a first-order kinetics. Crystalline Fe(III) is transformed into the amorphous form and reduced to Fe(II), hydroquinone functional groups in the humic acid (HA) are transformed to quinone ones, and the formation of HA-hematite ligands is promoted. Comparing with most of the studies about electron shuttling of HA, the transformation of quinone in the HA to hydroquinone could not be observed in the present bio-system. Based on column evaluations, more than 93% of chemical oxygen demand (influent concentration of 658 ± 19 mg L -1 ) could be removed microbially under flow conditions, when the hydraulic retention time was 45 h. Raw hematite-based Fe(III) bio-reduction has a promising potential for the removal of humic and benzene series in humified landfill leachate. Copyright © 2018. Published by Elsevier B.V.

  19. The 2010 Field Demonstration of the Solar Carbothermal Reduction of Regolith to Produce Oxygen

    NASA Technical Reports Server (NTRS)

    Gustafson, R. J.; White, B. C.; Fidler, M. J.; Muscatello, Anthony C.

    2010-01-01

    The Moon and other space exploration destinations are comprised of a variety of oxygen-bearing minerals, providing a virtually unlimited quantity of raw material which can be processed to produce oxygen. One attractive method to extract oxygen from the regolith is the carbothermal reduction process, which is not sensitive to variations in the mineral composition of the regolith. It also creates other valuable resources within the processed regolith, such as iron and silicon metals. Using funding from NASA, ORBITEC recently built and tested the Carbothermal Regolith Reduction Module to process lunar regolith simulants using concentrated solar energy. This paper summarizes the experimental test results obtained during a demonstration of the system at a lunar analog test site on the Mauna Kea volcano on Hawaii in February 2010.

  20. Smelting reduction and kinetics analysis of magnetic iron in copper slag using waste cooking oil.

    PubMed

    Li, Bo; Wang, Xubin; Wang, Hua; Wei, Yonggang; Hu, Jianhang

    2017-05-25

    To improve the recovery of copper, the viscosity of copper molten slag is decreased by the reduction of magnetic iron, which, in turn, accelerates the settling and separation of copper droplets from the slag. A new technology is proposed in which waste cooking oil is used as a reductant to reduce magnetic iron in the copper smelting slag and consequently reduce carbon emissions in the copper smelting process. A kinetic model of the reduction of magnetic iron in copper slag by waste cooking oil was built using experimental data, and the accuracy of the model was verified. The results indicated that the magnetic iron content in the copper slag decreased with increasing reduction time and an increase in temperature more efficiently reduced magnetic iron in the copper slag. The magnetic iron in the copper slag gradually transformed to fayalite, and the viscosity of the copper molten slag decreased as the magnetic iron content decreased during the reduction process. The reduction of magnetic iron in the copper molten slag using waste cooking oil was a first-order reaction, and the rate-limiting step was the mass transfer of Fe 3 O 4 through the liquid boundary layer.

  1. Defining harm reduction.

    PubMed

    Single, E

    1995-01-01

    Harm reduction attempts to reduce the adverse consequences of drug use among persons who continue to use drugs. It developed in response to the excesses of a "zero tolerance approach". Harm reduction emphasizes practical rather than idealized goals. It has been expanded from illicit drugs to legal drugs and is grounded in the evolving public health and advocacy movements. Harm reduction has proved to be effective and it has gained increasing official acceptance; for example, it is now the basis of Canada's Drug Strategy. However, the concept is still poorly defined, as virtually any drug policy or programme, even abstinence-oriented programmes, attempt to reduce drug-related harm. The principle feature of harm reduction is the acceptance of the fact that some drug users cannot be expected to cease their drug use at the present time. Harm reduction is neutral about the long term goals of intervention while according a high priority to short-term realizable goals. Harm reduction should be neutral about legalization. The essence of the concept is to ameliorate adverse consequences of drug use while, at least in the short term, drug use continues.

  2. From the ocean to a salt marsh: towards understanding iron reduction processes with FORC-PCA.

    NASA Astrophysics Data System (ADS)

    Muraszko, J. R.; Lascu, I.; Collins, S. M.; Harrison, R. J.

    2017-12-01

    Biogenic magnetic minerals are a high fidelity recorder of climate change. Their sensitivity to sedimentary redox conditions and bottom water ventilation have the potential to provide useful insights into past diagenetic conditions. However, the mechanisms controlling preservation and dissolution of magnetosomes are not fully understood, thus undermining the reliability of the paleomagnetic records in marine environments. Recovering information about the diagenetic past of the sediment is a crucial challenge; specifically, the biogenic components need to be identified and unmixed from the bulk magnetic signal. We address the issue in this study by applying Principal Component Analysis on First Order Reversal Curve diagrams (FORC-PCA) in case studies of cores obtained from the Iberian Margin and the sedimentologically active coastal salt marshes of Norfolk. We demonstrate the applicability of FORC-PCA as a new environmental proxy, yielding a high resolution temporal marine record of environmental changes reflected in magnetic composition over the last 194 kyr. The strongest variations are observed in the microbially derived components, the bulk properties of the sediment being controlled by a low coercivity SP-SD component which is generally anticorrelated with the magnetosome signal. Supported by TEM studies, we suggest the prevalence of clusters of nano-particles of magnetite associated with iron reduction. To further investigate the mechanisms controlling these processes, the active sedimentary environment of Norfolk was chosen as a case study of early diagenesis controlled by strong vertical geochemical gradients.

  3. Mechanism of Uranium Reduction and Immobilization in Desulfovibrio vulgaris Biofilms.

    PubMed

    Stylo, Malgorzata; Neubert, Nadja; Roebbert, Yvonne; Weyer, Stefan; Bernier-Latmani, Rizlan

    2015-09-01

    The prevalent formation of noncrystalline U(IV) species in the subsurface and their enhanced susceptibility to reoxidation and remobilization, as compared to crystalline uraninite, raise concerns about the long-term sustainability of the bioremediation of U-contaminated sites. The main goal of this study was to resolve the remaining uncertainty concerning the formation mechanism of noncrystalline U(IV) in the environment. Controlled laboratory biofilm systems (biotic, abiotic, and mixed biotic-abiotic) were probed using a combination of U isotope fractionation and X-ray absorption spectroscopy (XAS). Regardless of the mechanism of U reduction, the presence of a biofilm resulted in the formation of noncrystalline U(IV). Our results also show that biotic U reduction is the most effective way to immobilize and reduce U. However, the mixed biotic-abiotic system resembled more closely an abiotic system: (i) the U(IV) solid phase lacked a typically biotic isotope signature and (ii) elemental sulfur was detected, which indicates the oxidation of sulfide coupled to U(VI) reduction. The predominance of abiotic U reduction in our systems is due to the lack of available aqueous U(VI) species for direct enzymatic reduction. In contrast, in cases where bicarbonate is present at a higher concentration, aqueous U(VI) species dominate, allowing biotic U reduction to outcompete the abiotic processes.

  4. Solvent-driven reductive activation of carbon dioxide by gold anions.

    PubMed

    Knurr, Benjamin J; Weber, J Mathias

    2012-11-14

    Catalytic activation and electrochemical reduction of CO(2) for the formation of chemically usable feedstock and fuel are central goals for establishing a carbon neutral fuel cycle. The role of solvent molecules in catalytic processes is little understood, although solvent-solute interactions can strongly influence activated intermediate species. We use vibrational spectroscopy of mass-selected Au(CO(2))(n)(-) cluster ions to probe the solvation of AuCO(2)(-) as a model for a reactive intermediate in the reductive activation of a CO(2) ligand by a single-atom catalyst. For the first few solvent molecules, solvation of the complex preferentially occurs at the CO(2) moiety, enhancing reductive activation through polarization of the excess charge onto the partially reduced ligand. At higher levels of solvation, direct interaction of additional solvent molecules with the Au atom diminishes reduction. The results show how the solvation environment can enhance or diminish the effects of a catalyst, offering design criteria for single-atom catalyst engineering.

  5. Governing Staff Reductions: The Use and Abuse of Teacher Evaluations.

    ERIC Educational Resources Information Center

    Phelan, William T.

    1983-01-01

    Indicates that most principals and teachers interviewed in 16 school districts in Massachusetts agreed that performance evaluations should be part of the reduction in force (RIF) process. Examines performance assessments currently being done in selected districts. (MJL)

  6. Utilisation of polyurethane composit with 50% composition of roystonea regia fiber as noise reduction panel on car hood

    NASA Astrophysics Data System (ADS)

    Ikhwansyah; Mulia; Gunawan, S.; Lubis, R. D. W.

    2018-02-01

    The objective is to get the characteristics of noise reduction, noise reduction level, variety of measurement spaces, and knowing the process in making acoustic material of natural fiber becomes noise reduction on a car hood. The process of making noise reduction material used casting method and pressed by using molded press. The composition of noise reduction material consist of 50% roystonea regia by 32 mesh and 50% combined by gypsum and polyurethane. The result shows that the average result of noise reduction at X1- side is 5,7% and X2- side is 3,9%, X1+ side is 0,9% and X2+ side is 6,2%, Z1- side is 8,9% and Z2- side is 10,1%, Z1+ side is 9,7% and Z2+ side is 10,01%. The main conclusion of the study shows that a noise reduction which made of roystonea regia with 32 mesh mixed by matrix of polyurethane and gypsum is appropriate for noise reduction on car hood.

  7. Use of glucose as reductant to recover Co from spent lithium ions batteries.

    PubMed

    Meng, Qi; Zhang, Yingjie; Dong, Peng

    2017-06-01

    A hydrometallurgical leaching process has been developed for recovery of Co and Li from cathode material (LiCoO 2 ) collected from spent LIBs using a mix solution of glucose and phosphoric acid. The spent LiCoO 2 before and after leaching process are analyzed by scanning electron microscopy. A leaching rate of about 98% Co and nearly 100% Li is presented with 1.5mol/L phosphoric acid and 0.02mol/L glucose at 80°C in about 2h. During leaching process, glucose was oxidized into monocarboxylic acid with reduction of Co(III) to Co(II). Co in solution was recovered as Co-oxalate after leaching process. Using glucose as reductant to dissolve LiCoO 2 with chelating agent of phosphoric acid is achieved here. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. The influence of SRT on phosphorus removal and sludge characteristics in the HA-A/A-MCO sludge reduction process

    NASA Astrophysics Data System (ADS)

    Zuo, N.; Ji, F. Y.

    2013-02-01

    By researching the influence of sludge age (SRT) on phosphorous removal and sludge characteristics in the HA-A/A-MCO (hydrolysis-acidification-anaerobic/anoxic-multistep continuous oxic tank) process, which has the effect of simultaneous phosphorous and nitrogen removal and sludge reduction, it is found that extended SRT is helpful for improving the ability of anaerobic phosphorous release and chemical recovery of phosphate, but the hosphorous removal efficiency is not affected. Extended SRT causes the system to have even more active sludge; it can also lead to the system having a powerful ability of biochemical reaction by using superiority of concentration. Meanwhile, extended SRT can still reduce sludge yield. Extended SRT cannot make soluble metabolic product (SMP) accumulate in the reactor, so that the pollutant removal power is reduced; it also cannot affect the activity of the sludge. However, extended SRT is able to make the coagulation of the sludge hard, and cause the sludge volume index value increase, but cannot cause sludge bulking.

  9. The JCMT Gould Belt Survey: a quantitative comparison between SCUBA-2 data reduction methods

    NASA Astrophysics Data System (ADS)

    Mairs, S.; Johnstone, D.; Kirk, H.; Graves, S.; Buckle, J.; Beaulieu, S. F.; Berry, D. S.; Broekhoven-Fiene, H.; Currie, M. J.; Fich, M.; Hatchell, J.; Jenness, T.; Mottram, J. C.; Nutter, D.; Pattle, K.; Pineda, J. E.; Salji, C.; di Francesco, J.; Hogerheijde, M. R.; Ward-Thompson, D.; JCMT Gould Belt survey Team

    2015-12-01

    Performing ground-based submillimetre observations is a difficult task as the measurements are subject to absorption and emission from water vapour in the Earth's atmosphere and time variation in weather and instrument stability. Removing these features and other artefacts from the data is a vital process which affects the characteristics of the recovered astronomical structure we seek to study. In this paper, we explore two data reduction methods for data taken with the Submillimetre Common-User Bolometer Array-2 (SCUBA-2) at the James Clerk Maxwell Telescope (JCMT). The JCMT Legacy Reduction 1 (JCMT LR1) and The Gould Belt Legacy Survey Legacy Release 1 (GBS LR1) reduction both use the same software (STARLINK) but differ in their choice of data reduction parameters. We find that the JCMT LR1 reduction is suitable for determining whether or not compact emission is present in a given region and the GBS LR1 reduction is tuned in a robust way to uncover more extended emission, which better serves more in-depth physical analyses of star-forming regions. Using the GBS LR1 method, we find that compact sources are recovered well, even at a peak brightness of only three times the noise, whereas the reconstruction of larger objects requires much care when drawing boundaries around the expected astronomical signal in the data reduction process. Incorrect boundaries can lead to false structure identification or it can cause structure to be missed. In the JCMT LR1 reduction, the extent of the true structure of objects larger than a point source is never fully recovered.

  10. Role of heteroatoms in S, N-codoped nanoporous carbons in CO2 (photo)electrochemical reduction.

    PubMed

    Bandosz, Teresa; Li, Wanlu

    2018-06-19

    Thiourea-modified wood-based activated carbons were evaluated as catalysts for CO2 electrochemical reduction reaction (CO2ERR). The materials obtained at 950oC showed a long stability. The results indicated that thiophenic sulfur provides catalytic activity for CO formation. However, it was not as active for CH4 formation as was pyridinic-N. Tafel plots suggested that the nanoporous structure enhanced the kinetics for CO2 reduction. The electric conductivity limited the activity for CO2ERR in the materials modified at 600, 800 and 900oC. The effect of visible light on CO2ERR was also investigated in this study. Upon irradiation, photocurrent was generated, and a current density increased during CO2 reduction process. Combined with a band-gap alignment, the results indicate that thiophenic-S in the carbon matrix contributed to sample's photoactivity in visible light. These species enhance the overall reduction process promoting both hydrogen evolution reaction and CO2 reduction to CO. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Kinetics study of carbon raiser on the reduction of nickel laterite from Pomalaa, Southeast Sulawesi

    NASA Astrophysics Data System (ADS)

    Petrus, H. T. B. M.; Rhamdani, A. R.; Putera, A. D. P.; Warmada, I. W.; Yuliansyad, A. T.; Perdana, I.

    2016-11-01

    As one of the top ten on nickel laterite ore resources in the world, Indonesia must have been initiating the nickel processing in total amount of about 1.5 million tonnes. In regard to the low nickel laterite processing, one of the possible product is nickel pig iron (NPI) needed for the stainless steel industries. In this study carbon raiser that is waste from oil industries was used to replace metalurgical coke. The kinetic of nickel laterite reduction using carbon raiser was studied and compared with anthrasite coal. In this work, the author conducted the reduction of nickel laterite ores by both carbon raiser and anthrasite coal as reductant, in air and CO2 atmosphere, within the temperature ranged from 800°C and 1000°C. Two models were applied, sphere particle geometry model and Ginstling-Brounhstein diffusion model, to study the kinetic parameters. The results indicated that type of reductants and reduction atmosphere greatly influence the kinetic parameters. The obtained values of activation energy were varied between 17.44-18.12 kcal/mol.

  12. Fibrinogen Reduction During Selective Plasma Exchange due to Membrane Fouling.

    PubMed

    Ohkubo, Atsushi; Okado, Tomokazu; Miyamoto, Satoko; Hashimoto, Yurie; Komori, Shigeto; Yamamoto, Motoki; Maeda, Takuma; Itagaki, Ayako; Yamamoto, Hiroko; Seshima, Hiroshi; Kurashima, Naoki; Iimori, Soichiro; Naito, Shotaro; Sohara, Eisei; Uchida, Shinichi; Rai, Tatemitsu

    2017-06-01

    Fibrinogen is substantially reduced by most plasmapheresis modalities but retained in selective plasma exchange using Evacure EC-4A10 (EC-4A). Although EC-4A's fibrinogen sieving coefficient is 0, a session of selective plasma exchange reduced fibrinogen by approximately 19%. Here, we investigated sieving coefficient in five patients. When the mean processed plasma volume was 1.15 × plasma volume, the mean reduction of fibrinogen during selective plasma exchange was approximately 15%. Fibrinogen sieving coefficient was 0 when the processed plasma volume was 1.0 L, increasing to 0.07 when the processed plasma volume was 3.0 L, with a mean of 0.03 during selective plasma exchange. When fibrinogen sieving coefficient was 0, selective plasma exchange reduced fibrinogen by approximately 10%. Scanning electron microscopy images revealed internal fouling of EC-4A's hollow fiber membrane by substances such as fibrinogen fibrils. Thus, fibrinogen reduction by selective plasma exchange may be predominantly caused by membrane fouling rather than filtration. © 2017 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.

  13. Breast Reduction Surgery

    MedlinePlus

    ... considering breast reduction surgery, consult a board-certified plastic surgeon. It's important to understand what breast reduction surgery entails — including possible risks and complications — as ...

  14. Influence of calcium on microbial reduction of solid phase uranium(VI).

    PubMed

    Liu, Chongxuan; Jeon, Byong-Hun; Zachara, John M; Wang, Zheming

    2007-08-15

    The effect of calcium on the dissolution and microbial reduction of a representative solid phase uranyl [U(VI)], sodium boltwoodite (NaUO(2)SiO(3)OH . 1.5H(2)O), was investigated to evaluate the rate-limiting step of microbial reduction of the solid phase U(VI). Microbial reduction experiments were performed in a culture of a dissimilatory metal-reducing bacterium (DMRB), Shewanella oneidensis strain MR-1, in a bicarbonate medium with lactate as electron donor at pH 6.8 buffered with PIPES. Calcium increased the rate of Na-boltwoodite dissolution and U(VI) bioavailability by increasing its solubility through the formation of a ternary aqueous calcium-uranyl-carbonate species. The ternary species, however, decreased the rates of microbial reduction of aqueous U(VI). Laser-induced fluorescence spectroscopy (LIFS) and transmission electron microscopy (TEM) collectively revealed that microbial reduction of solid phase U(VI) was a sequentially coupled process of Na-boltwoodite dissolution, U(VI) aqueous speciation, and microbial reduction of dissolved U(VI) to U(IV) that accumulated on bacterial surfaces/periplasm. Under studied experimental conditions, the overall rate of microbial reduction of solid phase U(VI) was limited by U(VI) dissolution reactions in solutions without calcium and limited by microbial reduction in solutions with calcium. Generally, the overall rate of microbial reduction of solid phase U(VI) was determined by the coupling of solid phase U(VI) dissolution, U(VI) aqueous speciation, and microbial reduction of dissolved U(VI) that were all affected by calcium. (c) 2007 Wiley Periodicals, Inc.

  15. Characterising microbial reduction of arsenate sorbed to ferrihydrite and its concurrence with iron reduction.

    PubMed

    Huang, Jen-How

    2018-03-01

    A series of model anoxic incubations were performed to understand the concurrence between arsenate and ferrihydrite reduction by Shewanella putrefaciens strain CN-32 at different concentrations of arsenate, ferrihydrite and lactate, and with given ΔG rxn for arsenate and ferrihydrite reduction in non-growth conditions. The reduction kinetics of arsenate sorbed to ferrihydrite is predominately controlled by the availability of dissolved arsenate, which is measured by the integral of dissolved arsenate concentrations against incubation time and shown to correlate with the first order rate constants. High lactate concentrations slightly slowed down the rate of arsenate reduction due to the competition with arsenate for microbial contact. Under all experimental conditions, simultaneous arsenate and ferrihydrite reduction occurred following addition of S. putrefaciens inoculums and suggested no apparent competition between these two enzymatic reductions. Ferrous ions released from iron reduction might retard microbial arsenate reduction at high arsenate and ferrihydrite concentrations due to formation of ferrous arsenate. At high arsenate to ferrihydrite ratios, reductive dissolution of ferrihydrite shifted arsenate from sorption to dissolution and hence accelerated arsenate reduction. The interaction between microbial arsenate and ferrihydrite reduction did not correlate with ΔG rxn , but instead was governed by other factors such as geochemical and microbial parameters. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Software for Probabilistic Risk Reduction

    NASA Technical Reports Server (NTRS)

    Hensley, Scott; Michel, Thierry; Madsen, Soren; Chapin, Elaine; Rodriguez, Ernesto

    2004-01-01

    A computer program implements a methodology, denoted probabilistic risk reduction, that is intended to aid in planning the development of complex software and/or hardware systems. This methodology integrates two complementary prior methodologies: (1) that of probabilistic risk assessment and (2) a risk-based planning methodology, implemented in a prior computer program known as Defect Detection and Prevention (DDP), in which multiple requirements and the beneficial effects of risk-mitigation actions are taken into account. The present methodology and the software are able to accommodate both process knowledge (notably of the efficacy of development practices) and product knowledge (notably of the logical structure of a system, the development of which one seeks to plan). Estimates of the costs and benefits of a planned development can be derived. Functional and non-functional aspects of software can be taken into account, and trades made among them. It becomes possible to optimize the planning process in the sense that it becomes possible to select the best suite of process steps and design choices to maximize the expectation of success while remaining within budget.

  17. Investigation on the Oxidation and Reduction of Titanium in Molten Salt with the Soluble TiC Anode

    NASA Astrophysics Data System (ADS)

    Wang, Shulan; Wan, Chaopin; Liu, Xuan; Li, Li

    2015-12-01

    To reveal the oxidation process of titanium from TiC anode and the reduction mechanism of titanium ions in molten NaCl-KCl, the polarization curve of TiC anode in molten NaCl-KCl and cyclic voltammograms of the molten salt after polarization were studied. Investigation on the polarization curve shows that titanium can be oxidized and dissociated from the TiC anode at very low potential. The cyclic voltammograms demonstrated that the reduction reaction of titanium ions in the molten salt is a one-step process. By potentiostatic electrolysis, dendritic titanium is obtained on the steel plate. The work promotes the understanding on the process of electrochemical oxidization/dissociation of titanium from TiC anode and the reduction mechanism of titanium ions in molten salt.

  18. IN SITU DESTRUCTION OF CHLORINATED HYDROCARBON COMPOUNDS IN GROUNDWATER USING CATALYTIC REDUCTIVE REDUCTIVE DEHALOGENATION IN A REACTIVE WELL: TESTING AND OPERATIONAL EXPERIENCES. (R825421)

    EPA Science Inventory

    A groundwater treatment technology based on catalytic reductive
    dehalogenation has been developed to efficiently destroy chlorinated
    hydrocarbons in situ using a reactive well approach. The treatment process
    utilizes dissolved H2 as an electron donor, in...

  19. Vapor hydrogen peroxide as alternative to dry heat microbial reduction

    NASA Astrophysics Data System (ADS)

    Chung, S.; Kern, R.; Koukol, R.; Barengoltz, J.; Cash, H.

    2008-09-01

    The Jet Propulsion Laboratory (JPL), in conjunction with the NASA Planetary Protection Officer, has selected vapor phase hydrogen peroxide (VHP) sterilization process for continued development as a NASA approved sterilization technique for spacecraft subsystems and systems. The goal was to include this technique, with an appropriate specification, in NASA Procedural Requirements 8020.12 as a low-temperature complementary technique to the dry heat sterilization process. The VHP process is widely used by the medical industry to sterilize surgical instruments and biomedical devices, but high doses of VHP may degrade the performance of flight hardware, or compromise material compatibility. The goal for this study was to determine the minimum VHP process conditions for planetary protection acceptable microbial reduction levels. Experiments were conducted by the STERIS Corporation, under contract to JPL, to evaluate the effectiveness of vapor hydrogen peroxide for the inactivation of the standard spore challenge, Geobacillus stearothermophilus. VHP process parameters were determined that provide significant reductions in spore viability while allowing survival of sufficient spores for statistically significant enumeration. In addition to the obvious process parameters of interest: hydrogen peroxide concentration, number of injection cycles, and exposure duration, the investigation also considered the possible effect on lethality of environmental parameters: temperature, absolute humidity, and material substrate. This study delineated a range of test sterilizer process conditions: VHP concentration, process duration, a process temperature range for which the worst case D-value may be imposed, a process humidity range for which the worst case D-value may be imposed, and the dependence on selected spacecraft material substrates. The derivation of D-values from the lethality data permitted conservative planetary protection recommendations.

  20. Solid-State Metalized Reduction of Magnesium-Rich Low-Nickel Oxide Ores Using Coal as the Reductant Based on Thermodynamic Analysis

    NASA Astrophysics Data System (ADS)

    Ma, Baozhong; Xing, Peng; Yang, Weijiao; Wang, Chengyan; Chen, Yongqiang; Wang, Hua

    2017-08-01

    The solid-state metalized reduction of magnesium-rich low-nickel oxide ore using coal as a reductant was studied based on thermodynamic analysis. The major constituent minerals of the ore were silicates and goethite. The former was the main nickel-bearing mineral, and the latter was the main iron-bearing mineral. Single factor tests were conducted to investigate the effects of reduction temperature, duration, and coal dosage on the beneficiation of nickel and iron such that optimal conditions were achieved. Considering the low recoveries of nickel and iron (Ni, 13.9 pct; Fe, 30.3 pct) under the obtained optimal conditions, an improved process, adding CaF2 before the reaction, was proposed to modify the solid-state metalized process. The results showed that the recoveries of nickel and iron reached to 96.5 and 73.4 pct, respectively, and that the grades of nickel and iron in the concentrate increased from 2.5 and 62.6 wt pct to 6.9 and 71.4 wt pct, respectively. Nickel and iron in the absence of CaF2 were metalized; nevertheless, the size of ferronickel particles was only 1 μm. Furthermore, alloys in the presence of CaF2 aggregated and exhibited bands with a length greater than 200 µm. These observations suggested that CaF2 could effectively reduce the surface tension of the newly generated alloy interface and promote the migration and polymerization of the alloy particles, which improves the beneficiation of nickel and iron by magnetic separation.

  1. Optimization of a novel enzyme treatment process for early-stage processing of sheepskins.

    PubMed

    Lim, Y F; Bronlund, J E; Allsop, T F; Shilton, A N; Edmonds, R L

    2010-01-01

    An enzyme treatment process for early-stage processing of sheepskins has been previously reported by the Leather and Shoe Research Association of New Zealand (LASRA) as an alternative to current industry operations. The newly developed process had marked benefits over conventional processing in terms of a lowered energy usage (73%), processing time (47%) as well as water use (49%), but had been developed as a "proof of principle''. The objective of this work was to develop the process further to a stage ready for adoption by industry. Mass balancing was used to investigate potential modifications for the process based on the understanding developed from a detailed analysis of preliminary design trials. Results showed that a configuration utilising a 2 stage counter-current system for the washing stages and segregation and recycling of enzyme float prior to dilution in the neutralization stage was a significant improvement. Benefits over conventional processing include a reduction of residual TDS by 50% at the washing stages and 70% savings on water use overall. Benefits over the un-optimized LASRA process are reduction of solids in product after enzyme treatment and neutralization stages by 30%, additional water savings of 21%, as well as 10% savings of enzyme usage.

  2. Reduction in hospitalwide incidence of infection or colonization with methicillin-resistant Staphylococcus aureus with use of antimicrobial hand-hygiene gel and statistical process control charts.

    PubMed

    Harrington, Glenys; Watson, Kerrie; Bailey, Michael; Land, Gillian; Borrell, Susan; Houston, Leanne; Kehoe, Rosaleen; Bass, Pauline; Cockroft, Emma; Marshall, Caroline; Mijch, Anne; Spelman, Denis

    2007-07-01

    To evaluate the impact of serial interventions on the incidence of methicillin-resistant Staphylococcus aureus (MRSA). Longitudinal observational study before and after interventions. The Alfred Hospital is a 350-bed tertiary referral hospital with a 35-bed intensive care unit (ICU). A series of interventions including the introduction of an antimicrobial hand-hygiene gel to the intensive care unit and a hospitalwide MRSA surveillance feedback program that used statistical process control charts but not active surveillance cultures. Serial interventions were introduced between January 2003 and May 2006. The incidence and rates of new patients colonized or infected with MRSA and episodes of MRSA bacteremia in the intensive care unit and hospitalwide were compared between the preintervention and intervention periods. Segmented regression analysis was used to calculate the percentage reduction in new patients with MRSA and in episodes of MRSA bacteremia hospitalwide in the intervention period. The rate of new patients with MRSA in the ICU was 6.7 cases per 100 patient admissions in the intervention period, compared with 9.3 cases per 100 patient admissions in the preintervention period (P=.047). The hospitalwide rate of new patients with MRSA was 1.7 cases per 100 patient admissions in the intervention period, compared with 3.0 cases per 100 patient admissions in the preintervention period (P<.001). By use of segmented regression analysis, the maximum and conservative estimates for percentage reduction in the rate of new patients with MRSA were 79.5% and 42.0%, respectively, and the maximum and conservative estimates for percentage reduction in the rate of episodes of MRSA bacteremia were 87.4% and 39.0%, respectively. A sustained reduction in the number of new patients with MRSA colonization or infection has been demonstrated using minimal resources and a limited number of interventions.

  3. DEMONSTRATION BULLETIN: GAS-PHASE CHEMICAL REDUCTION - ECO LOGIC INTERNATIONAL, INC.

    EPA Science Inventory

    The patented Eco Logic Process employs a gas-phase reduction reaction of hydrogen with organic and chlorinated organic compounds at elevated temperatures to convert aqueous and oily hazardous contaminants into a hydrocarbon-rich gas product. After passing through a scrubber, the ...

  4. Binuclear Phthalocyanines as Model Electrocatalysts for the Reduction of Oxygen.

    DTIC Science & Technology

    1985-05-01

    solution, in which case the final product is Co(II)Pc. Aqueous acid addition (under nitrogen) to Co(I)Pc (in DCB/OH-) yields Co(II)Pc and presumably hydrogen ...little doubt, given the tendency for Co(I) to reduce aqueous acid to hydrogen [101, that hydrogen is produced in this reaction, though it was not proven...reduction occurs in water by a 2-electron process to hydrogen peroxide or a 4-electron process to water. This latter process must be catalysed on a

  5. Programmed emulsions for sodium reduction in emulsion based foods.

    PubMed

    Chiu, Natalie; Hewson, Louise; Fisk, Ian; Wolf, Bettina

    2015-05-01

    In this research a microstructure approach to reduce sodium levels in emulsion based foods is presented. If successful, this strategy will enable reduction of sodium without affecting consumer satisfaction with regard to salty taste. The microstructure approach comprised of entrapment of sodium in the internal aqueous phase of water-in-oil-in-water emulsions. These were designed to destabilise during oral processing when in contact with the salivary enzyme amylase in combination with the mechanical manipulation of the emulsion between the tongue and palate. Oral destabilisation was achieved through breakdown of the emulsion that was stabilised with a commercially modified octenyl succinic anhydride (OSA)-starch. Microstructure breakdown and salt release was evaluated utilising in vitro, in vivo and sensory methods. For control emulsions, stabilised with orally inert proteins, no loss of structure and no release of sodium from the internal aqueous phase was found. The OSA-starch microstructure breakdown took the initial form of oil droplet coalescence. It is hypothesised that during this coalescence process sodium from the internalised aqueous phase is partially released and is therefore available for perception. Indeed, programmed emulsions showed an enhancement in saltiness perception; a 23.7% reduction in sodium could be achieved without compromise in salty taste (p < 0.05; 120 consumers). This study shows a promising new approach for sodium reduction in liquid and semi-liquid emulsion based foods.

  6. Mistletoe-induced growth reductions at the forest stand scale.

    PubMed

    Kollas, Chris; Gutsch, Martin; Hommel, Robert; Lasch-Born, Petra; Suckow, Felicitas

    2018-05-01

    The hemiparasite European mistletoe (Viscum album L.) adversely affects growth and reproduction of the host Scots pine (Pinus sylvestris L.) and in consequence may lead to tree death. Here, we aimed to estimate mistletoe-induced losses in timber yield applying the process-based forest growth model 4C. The parasite was implemented into the eco-physiological forest growth model 4C using (literature-derived) established impacts of the parasite on the tree's water and carbon cycle. The amended model was validated simulating a sample forest stand in the Berlin area (Germany) comprising trees with and without mistletoe infection. At the same forest stand, tree core measurements were taken to evaluate simulated and observed growth. A subsample of trees were harvested to quantify biomass compartments of the tree canopy and to derive a growth function of the mistletoe population. The process-based simulations of the forest stand revealed 27% reduction in basal area increment (BAI) during the last 9 years of heavy infection, which was confirmed by the measurements (29% mean growth reduction). The long-term simulations of the forest stand before and during the parasite infection showed that the amended forest growth model 4C depicts well the BAI growth pattern during >100 years and also quantifies well the mistletoe-induced growth reductions in Scots pine stands.

  7. Deposition of silver nanoparticles on multiwalled carbon nanotubes by chemical reduction process and their antimicrobial effects

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Haider, Adawiya J., E-mail: adawiyahaider@yahoo.com; Thamir, Amin D.; Ahmed, Duha S.

    In this paper, the functionalization of raw-MWCNTs involves oxidation reaction using concentrated acid mixture of HNO{sub 3}:H{sub 2}SO{sub 4} (1:3), via ultrasonic bath (170 W, 50 kHz) to obtain functional groups. Then Ag nanoparticles are decorated the outside over the surface of functionalized MWCNTs using a chemical reduction process resulting in the formation of(Ag/ MWCNTs) hybrid material. The results showed that outer diameter functionalized F-MWCNTs andAg nanoparticles size was about (11-80) nm and (10 to 25) nm, respectively using TEM and HRTEM. The crystallographic structure of MWCNTs using X-ray diffraction (XRD) analysis proved diffraction peaks at 38.1°, 44.3°, 64.7° andmore » 77.4° degrees namely, Ag (111), Ag (200), Ag (220), and Ag (311) of the face-centered cubic lattice of Ag, respectively, excepting the peak at 2θ =25.6°, which correspond to the (0 0 2) reflection of the MWNTs are corresponding to Ag/MWNTs. The antimicrobial activities of Ag/MWCNTs hybrid using plate count method showed that decreasing a large number of bacteria colonies of E. coli and S. aureu with increasing the hybrid concentrations after incubation for 24 h in shaker incubator with percentage of inhibition approaching 100%.« less

  8. Strategies to reduce mass and photons transfer limitations in heterogeneous photocatalytic processes: Hexavalent chromium reduction studies.

    PubMed

    Marinho, Belisa A; Cristóvão, Raquel O; Djellabi, Ridha; Caseiro, Ana; Miranda, Sandra M; Loureiro, José M; Boaventura, Rui A R; Dias, Madalena M; Lopes, José Carlos B; Vilar, Vítor J P

    2018-07-01

    The current work presents different approaches to overcome mass and photon transfer limitations in heterogeneous photocatalytic processes applied to the reduction of hexavalent chromium to its trivalent form in the presence of a sacrificial agent. Two reactor designs were tested, a monolithic tubular photoreactor (MTP) and a micro-meso-structured photoreactor (NETmix), both presenting a high catalyst surface area per reaction liquid volume. In order to reduce photon transfer limitations, the tubular photoreactor was packed with transparent cellulose acetate monolithic structures (CAM) coated with the catalyst by a dip-coating method. For the NETmix reactor, a thin film of photocatalyst was uniformly deposited on the front glass slab (GS) or on the network of channels and chambers imprinted in the back stainless steel slab (SSS) using a spray system. The reaction rate for the NETmix photoreactor was evaluated for two illumination sources, solar light or UVA-LEDs, using the NETmix with the front glass slab or/and back stainless steel slab coated with TiO 2 -P25. The reusability of the photocatalytic films on the NETmix walls was also evaluated for three consecutive cycles using fresh Cr(VI) solutions. The catalyst reactivity in combination with the NETmix-SSS photoreactor is almost 70 times superior to one obtained with the MTP. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. A randomized trial of pneumatic reduction versus hydrostatic reduction for intussusception in pediatric patients.

    PubMed

    Xie, Xiaolong; Wu, Yang; Wang, Qi; Zhao, Yiyang; Chen, Guobin; Xiang, Bo

    2017-08-08

    Data of randomly controlled trials comparing the hydrostatic and pneumatic reduction for intussusception in pediatric patients as initial therapy are lacking. The aim of this study was to conduct a randomly controlled trial to compare the effectiveness and safety of the hydrostatic and pneumatic reduction techniques. All intussusception patients who visited West China Hospital of Sichuan University from January 2014 to December 2015 were enrolled in this study in which they underwent pneumatic reduction or hydrostatic reduction. Patients were randomized into ultrasound-guided hydrostatic or X-ray-guided pneumatic reduction group. The data collected includes demographic data, symptoms, signs, and investigations. The primary outcome of the study was the success rate of reduction. And the secondary outcomes of the study were the rates of intestinal perforations and recurrence. A total of 124 children with intussusception who had met the inclusion criteria were enrolled. The overall success rate of this study was 90.32%. Univariable analysis showed that the success rate of hydrostatic reduction with normal saline (96.77%) was significantly higher than that of pneumatic reduction with air (83.87%) (p=0.015). Perforation after reduction was found in only one of the pneumatic reduction group. The recurrence rate of intussusception in the hydrostatic reduction group was 4.84% compared with 3.23% of pneumatic reduction group. Our study found that ultrasound-guided hydrostatic reduction is a simple, safe and effective nonoperative treatment for pediatric patients suffering from intussusceptions, and should be firstly adopted in the treatment of qualified patients. Therapeutic study TYPE OF STUDY: Prospective study. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Noise reduction in plasmonic amplifiers

    NASA Astrophysics Data System (ADS)

    Vyshnevyy, Andrey A.; Fedyanin, Dmitry Yu.

    2018-06-01

    Surface plasmon polaritons amplification give the possibility to overcome strong absorption in metals and design truly nanoscale devices for on-chip photonic circuits. However, the process of stimulated emission in the gain medium is inevitably accompanied by spontaneous emission, which greatly increases the noise power. Herein we present an efficient strategy for noise reduction in plasmonic amplifiers,which is based on gain redistribution along the amplifier. We show that even a very small gain redistribution (∼3%) makes it possible to increase the signal-to-noise ratio by ∼100% and improve the bit error ratio by orders of magnitude.

  11. Method for oxygen reduction in a uranium-recovery process. [US DOE patent application

    DOEpatents

    Hurst, F.J.; Brown, G.M.; Posey, F.A.

    1981-11-04

    An improvement in effecting uranium recovery from phosphoric acid solutions is provided by sparging dissolved oxygen contained in solutions and solvents used in a reductive stripping stage with an effective volume of a nonoxidizing gas before the introduction of the solutions and solvents into the stage. Effective volumes of nonoxidizing gases, selected from the group consisting of argon, carbon dioxide, carbon monoxide, helium, hydrogen, nitrogen, sulfur dioxide, and mixtures thereof, displace oxygen from the solutions and solvents thereby reduce deleterious effects of oxygen such as excessive consumption of elemental or ferrous iron and accumulation of complex iron phosphates or cruds.

  12. A survey of analytical methods employed for monitoring of Advanced Oxidation/Reduction Processes for decomposition of selected perfluorinated environmental pollutants.

    PubMed

    Trojanowicz, Marek; Bobrowski, Krzysztof; Szostek, Bogdan; Bojanowska-Czajka, Anna; Szreder, Tomasz; Bartoszewicz, Iwona; Kulisa, Krzysztof

    2018-01-15

    The monitoring of Advanced Oxidation/Reduction Processes (AO/RPs) for the evaluation of the yield and mechanisms of decomposition of perfluorinated compounds (PFCs) is often a more difficult task than their determination in the environmental, biological or food samples with complex matrices. This is mostly due to the formation of hundreds, or even thousands, of both intermediate and final products. The considered AO/RPs, involving free radical reactions, include photolytic and photocatalytic processes, Fenton reactions, sonolysis, ozonation, application of ionizing radiation and several wet oxidation processes. The main attention is paid to the most commonly occurring PFCs in the environment, namely PFOA and PFOS. The most powerful and widely exploited method for this purpose is without a doubt LC/MS/MS, which allows the identification and trace quantitation of all species with detectability and resolution power depending on the particular instrumental configurations. The GC/MS is often employed for the monitoring of volatile fluorocarbons, confirming the formation of radicals in the processes of C‒C and C‒S bonds cleavage. For the direct monitoring of radicals participating in the reactions of PFCs decomposition, the molecular spectrophotometry is employed, especially electron paramagnetic resonance (EPR). The UV/Vis spectrophotometry as a detection method is of special importance in the evaluation of kinetics of radical reactions with the use of pulse radiolysis methods. The most commonly employed for the determination of the yield of mineralization of PFCs is ion-chromatography, but there is also potentiometry with ion-selective electrode and the measurements of general parameters such as Total Organic Carbon and Total Organic Fluoride. The presented review is based on about 100 original papers published in both analytical and environmental journals. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. 40 CFR 430.24 - Effluent limitations representing the degree of effluent reduction attainable by the application...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... new technology components or process modifications and identifying critical path relationships within... degree of effluent reduction attainable by the application of best available technology economically... effluent reduction attainable by the application of best available technology economically achievable (BAT...

  14. Jet Noise Reduction

    NASA Technical Reports Server (NTRS)

    Kenny, Patrick

    2004-01-01

    at the AAPL to measure Nozzle Acoustic Test Rig (NATR) background noise levels. Six condenser microphones were placed in strategic locations around the dome and the inlet tunnel to measure different noise sources. From the control room the jet was monitored with the help of video cameras and other sensors. The data points were recorded, reduced, and plotted, and will be used to plan future modifications to the NATR. The primary goal to create data reduction test programs and provide verification was completed. As a result of the internship, I learned C/C++, UNIX/LINUX, Excel, and acoustic data processing methods. I also recorded data at the AAPL, then processed and plotted it. These data would be useful to compare against existing data. In addition, I adjusted software to work on the Mac OSX platform. And I used the available training resources.

  15. Reductive dissolution and reactive solute transport in a sewage-contaminated glacial outwash aquifer

    USGS Publications Warehouse

    Lee, R.W.; Bennett, P.C.

    1998-01-01

    Contamination of shallow ground water by sewage effluent typically contains reduced chemical species that consume dissolved oxygen, developing either a low oxygen geochemical environment or an anaerobic geochemical environment. Based on the load of reduced chemical species discharged to shallow ground water and the amounts of reactants in the aquifer matrix, it should be possible to determine chemical processes in the aquifer and compare observed results to predicted ones. At the Otis Air Base research site (Cape Cod, Massachusetts) where sewage effluent has infiltrated the shallow aquifer since 1936, bacterially mediated processes such as nitrification, denitrification, manganese reduction, and iron reduction have been observed in the contaminant plume. In specific areas of the plume, dissolved manganese and iron have increased significantly where local geochemical conditions are favorable for reduction and transport of these constituents from the aquifer matrix. Dissolved manganese and iron concentrations ranged from 0.02 to 7.3 mg/L, and 0.001 to 13.0 mg/L, respectively, for 21 samples collected from 1988 to 1989. Reduction of manganese and iron is linked to microbial oxidation of sewage carbon, producing bicarbonate and the dissolved metal ions as by-products. Calculated production and flux of CO2 through the unsaturated zone from manganese reduction in the aquifer was 0.035 g/m2/d (12% of measured CO2 flux during winter). Manganese is limited in the aquifer, however. A one-dimensional, reaction-coupled transport model developed for the mildly reducing conditions in the sewage plume nearest the source beds showed that reduction, transport, and removal of manganese from the aquifer sediments should result in iron reduction where manganese has been depleted.

  16. DFT Study on Nitrite Reduction Mechanism in Copper-Containing Nitrite Reductase.

    PubMed

    Lintuluoto, Masami; Lintuluoto, Juha M

    2016-01-12

    Dissimilatory reduction of nitrite by copper-containing nitrite reductase (CuNiR) is an important step in the geobiochemical nitrogen cycle. The proposed mechanisms for the reduction of nitrite by CuNiRs include intramolecular electron and proton transfers, and these two events are understood to couple. Proton-coupled electron transfer is one of the key processes in enzyme reactions. We investigated the geometric structure of bound nitrite and the mechanism of nitrite reduction on CuNiR using density functional theory calculations. Also, the proton transfer pathway, the key residues, and their roles in the reaction mechanism were clarified in this study. In our results, the reduction of T2 Cu site promotes the proton transfer, and the hydrogen bond network around the binding site has an important role not only to stabilize the nitrite binding but also to promote the proton transfer to nitrite.

  17. On the genesis of molybdenum carbide phases during reduction-carburization reactions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guil-Lopez, R., E-mail: rut.guil@icp.csic.es; Nieto, E.; Departamento de Tecnologia Quimica y Energetica, ESCET, Universidad Rey Juan Carlos, C/Tulipan s/n, 28933-Mostoles

    2012-06-15

    Molybdenum carbide has been prepared according to the carbothermal reduction method. Carbon black substrate was used as C-source whereas a H{sub 2}-flow was the reducing agent. Two different H{sub 2} consumption steps were identified during the carburization treatment. The low temperature step is related to the reduction of Mo{sup 6+}-to-Mo{sup 4+}, the higher temperature process accounts for the deep reduction of Mo{sup 4+}-to-metal Mo{sup 0} and its subsequent reaction with C to form the Mo-carbide. The influences of the maximum carburization temperature, carburization time, gas hourly space velocity regarding Mo-loading, heating rate and temperature of Ar pre-treatment were analyzed. Allmore » these conditions are interrelated to each other. Thus, the carburization process ends at 700 Degree-Sign C when Mo-loading is 10 wt%, however Mo-loading higher than 10 wt% requires higher temperatures. Carburization temperatures up to 800 Degree-Sign C are needed to fulfill Mo-carbide formation with samples containing 50 wt% Mo. Nevertheless, Ar pre-treatment at 550 Degree-Sign C and slow heating rates favor the carburization, thus requiring lower carburization temperatures to reach the same carburization level. - Graphical Abstract: H{sub 2}-consumption profile (TPR) during the molybdenum carburization process, XRD patterns of the reduced Mo-samples after carburization and TEM-micrographs with two different enlargement of the samples with 5, 20 and 50 wt% Mo. Highlights: Black-Right-Pointing-Pointer Control of carburization variables: tailor the reduced/carbide Mo-phases (single/mixture). Black-Right-Pointing-Pointer Mo carburization in two stages: (1) Mo{sup 6+}-Mo{sup 4+}; (2) Mo{sup 4+}-Mo{sup 0} and, at once, MoC. Black-Right-Pointing-Pointer The carburization process is faster than Mo{sup 4+} reduction. Black-Right-Pointing-Pointer XPS probed: reduced Mo particles show core-shell structure. Black-Right-Pointing-Pointer Core: reduced Mo (Mo{sub 2}C, MoO{sub 2} and

  18. Evaluation of selected chemical processes for production of low-cost silicon

    NASA Technical Reports Server (NTRS)

    Blocher, J. M., Jr.; Browning, M. F.; Wilson, W. J.; Carmichael, D. C.

    1976-01-01

    Plant construction costs and manufacturing costs were estimated for the production of solar-grade silicon by the reduction of silicon tetrachloride in a fluidized bed of seed particles, and several modifications of the iodide process using either thermal decomposition on heated filaments (rods) or hydrogen reduction in a fluidized bed of seed particles. Energy consumption data for the zinc reduction process and each of the iodide process options are given and all appear to be acceptable from the standpoint of energy pay back. Information is presented on the experimental zinc reduction of SiCl4 and electrolytic recovery of zinc from ZnCl2. All of the experimental work performed thus far has supported the initial assumption as to technical feasibility of producing semiconductor silicon by the zinc reduction or iodide processes proposed. The results of a more thorough thermodynamic evaluation of the iodination of silicon oxide/carbon mixtures are presented which explain apparent inconsistencies in an earlier cursory examination of the system.

  19. Reduced graphene oxide supported gold nanoparticles for electrocatalytic reduction of carbon dioxide

    NASA Astrophysics Data System (ADS)

    Saquib, Mohammad; Halder, Aditi

    2018-02-01

    Electrochemical reduction of carbon dioxide is one of the methods which have the capability to recycle CO2 into valuable products for energy and industrial applications. This research article describes about a new electrocatalyst "reduced graphene oxide supported gold nanoparticles" for selective electrochemical conversion of carbon dioxide to carbon monoxide. The main aim for conversion of CO2 to CO lies in the fact that the latter is an important component of syn gas (a mixture of hydrogen and carbon monoxide), which is then converted into liquid fuel via well-known industrial process called Fischer-Tropsch process. In this work, we have synthesized different composites of the gold nanoparticles supported on defective reduced graphene oxide to evaluate the catalytic activity of reduced graphene oxide (RGO)-supported gold nanoparticles and the role of defective RGO support towards the electrochemical reduction of CO2. Electrochemical and impedance measurements demonstrate that higher concentration of gold nanoparticles on the graphene support led to remarkable decrease in the onset potential of 240 mV and increase in the current density for CO2 reduction. Lower impedance and Tafel slope values also clearly support our findings for the better performance of RGOAu than bare Au for CO2 reduction.

  20. Reduction of produced elementary sulfur in denitrifying sulfide removal process.

    PubMed

    Zhou, Xu; Liu, Lihong; Chen, Chuan; Ren, Nanqi; Wang, Aijie; Lee, Duu-Jong

    2011-05-01

    Denitrifying sulfide removal (DSR) processes simultaneously convert sulfide, nitrate, and chemical oxygen demand from industrial wastewater into elemental sulfur, dinitrogen gas, and carbon dioxide, respectively. The failure of a DSR process is signaled by high concentrations of sulfide in reactor effluent. Conventionally, DSR reactor failure is blamed for overcompetition for heterotroph to autotroph communities. This study indicates that the elementary sulfur produced by oxidizing sulfide that is a recoverable resource from sulfide-laden wastewaters can be reduced back to sulfide by sulfur-reducing Methanobacterium sp. The Methanobacterium sp. was stimulated with excess organic carbon (acetate) when nitrite was completely consumed by heterotrophic denitrifiers. Adjusting hydraulic retention time of a DSR reactor when nitrite is completely consumed provides an additional control variable for maximizing DSR performance.